Search results for: health data standards
Commenced in January 2007
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Paper Count: 30544

Search results for: health data standards

664 Natural Fibers Design Attributes

Authors: Brayan S. Pabón, R. Ricardo Moreno, Edith Gonzalez

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Inside the wide Colombian natural fiber set is the banana stem leaf, known as Calceta de Plátano, which is a material present in several regions of the country and is a fiber extracted from the pseudo stem of the banana plant (Musa paradisiaca) as a regular maintenance process. Colombia had a production of 2.8 million tons in 2007 and 2008 corresponding to 8.2% of the international production, number that is growing. This material was selected to be studied because it is not being used by farmers due to it being perceived as a waste from the banana harvest and a propagation pest agent inside the planting. In addition, the Calceta does not have industrial applications in Colombia since there is not enough concrete knowledge that informs us about the properties of the material and the possible applications it could have. Based on this situation the industrial design is used as a link between the properties of the material and the need to transform it into industrial products for the market. Therefore, the project identifies potential design attributes that the banana stem leaf can have for product development. The methodology was divided into 2 main chapters: Methodology for the material recognition: -Data Collection, inquiring the craftsmen experience and bibliography. -Knowledge in practice, with controlled experiments and validation tests. -Creation of design attributes and material profile according to the knowledge developed. Moreover, the Design methodology: -Application fields selection, exploring the use of the attributes and the relation with product functions. -Evaluating the possible fields and selection of the optimum application. -Design Process with sketching, ideation, and product development. Different protocols were elaborated to qualitatively determine some material properties of the Calceta, and if they could be designated as design attributes. Once defined, performed and analyzed the validation protocols, 25 design attributes were identified and classified into 4 attribute categories (Environmental, Functional, Aesthetics and Technical) forming the material profile. Then, 15 application fields were defined based on the relation between functions of product and the use of the Calceta attributes. Those fields were evaluated to measure how much are being used the functional attributes. After fields evaluation, a final field was defined , influenced by traditional use of the fiber for packing food. As final result, two products were designed for this application field. The first one is the Multiple Container, which works to contain small or large-thin pieces of food, like potatoes chips or small sausages; it allows the consumption of food with sauces or dressings. The second is the Chorizo container, specifically designed for this food due to the long shape and the consumption mode. Natural fiber research allows the generation of a solider and a more complete knowledge about natural fibers. In addition, the research is a way to strengthen the identity through the investigation of the proper and autochthonous, allowing the use of national resources in a sustainable and creative way. Using divergent thinking and the design as a tool, this investigation can achieve advances in the natural fiber handling.

Keywords: banana stem leaf, Calceta de Plátano, design attributes, natural fibers, product design

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663 The Forms of Representation in Architectural Design Teaching: The Cases of Politecnico Di Milano and Faculty of Architecture of the University of Porto

Authors: Rafael Sousa Santos, Clara Pimena Do Vale, Barbara Bogoni, Poul Henning Kirkegaard

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The representative component, a determining aspect of the architect's training, has been marked by an exponential and unprecedented development. However, the multiplication of possibilities has also multiplied uncertainties about architectural design teaching, and by extension, about the very principles of architectural education. In this paper, it is intended to present the results of a research developed on the following problem: the relation between the forms of representation and the architectural design teaching-learning processes. The research had as its object the educational model of two schools – the Politecnico di Milano (POLIMI) and the Faculty of Architecture of the University of Porto (FAUP) – and was led by three main objectives: to characterize the educational model followed in both schools focused on the representative component and its role; to interpret the relation between forms of representation and the architectural design teaching-learning processes; to consider their possibilities of valorisation. Methodologically, the research was conducted according to a qualitative embedded multiple-case study design. The object – i.e., the educational model – was approached in both POLIMI and FAUP cases considering its Context and three embedded unities of analysis: the educational Purposes, Principles, and Practices. In order to guide the procedures of data collection and analysis, a Matrix for the Characterization (MCC) was developed. As a methodological tool, the MCC allowed to relate the three embedded unities of analysis with the three main sources of evidence where the object manifests itself: the professors, expressing how the model is assumed; the architectural design classes, expressing how the model is achieved; and the students, expressing how the model is acquired. The main research methods used were the naturalistic and participatory observation, in-person-interview and documentary and bibliographic review. The results reveal the importance of the representative component in the educational model of both cases, despite the differences in its role. In POLIMI's model, representation is particularly relevant in the teaching of architectural design, while in FAUP’s model, it plays a transversal role – according to an idea of 'general training through hand drawing'. In fact, the difference between models relative to representation can be partially understood by the level of importance that each gives to hand drawing. Regarding the teaching of architectural design, the two cases are distinguished in the relation with the representative component: while in POLIMI the forms of representation serve essentially an instrumental purpose, in FAUP they tend to be considered also for their methodological dimension. It seems that the possibilities for valuing these models reside precisely in the relation between forms of representation and architectural design teaching. It is expected that the knowledge base developed in this research may have three main contributions: to contribute to the maintenance of the educational model of POLIMI and FAUP; through the precise description of the methodological procedures, to contribute by transferability to similar studies; through the critical and objective framework of the problem underlying the forms of representation and its relation with architectural design teaching, to contribute to the broader discussion concerning the contemporary challenges on architectural education.

Keywords: architectural design teaching, architectural education, educational models, forms of representation

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662 Mistletoe Supplementation and Exercise Training on IL-1β and TNF-α Levels

Authors: Alireza Barari, Ahmad Abdi

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Introduction: Plyometric training (PT) is popular among individuals involved in dynamic sports, and is executed with a goal to improve muscular performance. Cytokines are considered as immunoregulatory molecules for regulation of immune function and other body responses. In addition, the pro-inflammatory cytokines, TNF-α andIL-1β, have been reported to be increased during and after exercises. If some of the cytokines which cause responses such as inflammation of cells in skeletal muscles, with manipulating of training program or optimizing nutrition, it can be avoided or limited from those injuries caused by cytokines release. Its shows that mistletoe extracts show immune-modulating effects. Materials and methods: present study was to investigate the effect of six weeks PT with or without mistletoe supplementation (MS)(10 mg/kg) on cytokine responses and performance in male basketball players. This study is semi-experimental. Statistic society of this study was basketball player’s male students of Mahmoud Abad city. Statistic samples are concluded of 32 basketball players with an age range of 14–17 years was selected from randomly. Selection of samples in four groups of 8 individuals Participants were randomly assigned to either an experimental group (E, n=16) that performed plyometric exercises with (n=8) or without (n=8) MS, or a control group that rested (C, n=16) with (n=8) or without (n=8) MS. Plants were collected in June from the Mazandaran forest in north of Iran. Then they dried in exposure to air without any exposition to sunlight, on a clean textile. For better drying the plants were high and down until they lost their water. Each subject consumed 10 mg/kg/day of extract for six weeks of intervention. Pre and post-testing was performed in the afternoon of the same day. Blood samples (10 ml) were collected from the intermediate cubital vein of the subjects. Serum concentration of IL-1β and TNF-α were measured by ELISA method. Data analysis was performed using pretest to posttest changes that assessed by t-test for paired samples. After the last plyometric training program, the second blood samples were in the next day. Group differences at baseline were evaluated using One-way ANOVA (post-hock Tukey) test is used for analysis and comparison of three group’s variables. Results: PT with or without MS improved the one repetition maximum leg and chest press, Sargeant test and power in RAST (P < 0.05). However there were no statistically significant differences between groups in Vo2max measures (P > 0.05). PT resulted in a significant increase in plasma IL-1β concentration from 1.08±0.4 mg/ml in pre-training to 1.68±0.18 mg/ml in post-training (P=0.006). While the MS significantly decreased the training-induced increment of IL-1β (P=0.007). In contrast, neither PT nor MS had any effect on TNF-α levels (P > 0.05). Discussion: The results of this investigation indicate that PT improved muscular performance and increases the IL-1β concentration. Increasing of IL-1β after exercise in damaged skeletal muscle has shown of the role of this cytokine in inflammation processes and damaged skeletal muscle repair. However mistletoe supplementation ameliorates the increment of IL-1β levels, indicating the beneficial effect of mistletoe on immune response following plyometric training.

Keywords: mistletoe supplementation, training, IL-1β, TNF-α

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661 Spatial and Temporal Variability of Meteorological Drought Including Atmospheric Circulation in Central Europe

Authors: Andrzej Wałęga, Marta Cebulska, Agnieszka Ziernicka-Wojtaszek, Wojciech Młocek, Agnieszka Wałęga, Tommaso Caloiero

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Drought is one of the natural phenomena influencing many aspects of human activities like food production, agriculture, industry, and the ecological conditions of the environment. In the area of the Polish Carpathians, there are periods with a deficit of rainwater and an increasing frequency in dry months, especially in the cold half of the year. The aim of this work is a spatial and temporal analysis of drought, expressed as SPI in a heterogenous area of the Polish Carpathian and of the highland Region in the Central part of Europe based on long-term precipitation data. Also, to our best knowledge, for the first time in this work, drought characteristics analyzed via the SPI were discussed based on the atmospheric circulation calendar. The study region is the Upper Vistula Basin, located in the southern and south-eastern part of Poland. In this work, monthly precipitation from 56 rainfall stations was analysed from 1961 to 2022. The 3-, 6-, 9-, and 12-month Standardized Precipitation Index (SPI) were used as indicators of meteorological drought. For the 3-month SPI, the main climatic mechanisms determining extreme droughts were defined based on the calendar of synoptic circulations. The Mann-Kendall test was used to detect the trend of extreme droughts. Statistically significant trends of SPI were observed on 52.7% of all analyzed stations, and in most cases, a positive trend was observed. Statistically significant trends were more frequently observed in stations located in the western part of the analyzed region. Long-term droughts, represented by the 12-month SPI, occurred in all stations but not in all years. Short-term droughts (3-month SPI) were most frequent in the winter season, 6 and 9-month SPI in winter and spring, and 12-month SPI in winter and autumn, respectively. The spatial distribution of drought was highly diverse. The most intensive drought occurred in 1984, with the 6-month SPI covering 98% of the analyzed region and the 9 and 12-month SPI covering 90% of the entire region. Droughts exhibit a seasonal pattern, with a dominant 10-year periodicity for all analyzed variants of SPI. Additionally, Fourier analysis revealed a 2-year periodicity for the 3-, 6-, and 9-month SPI and a 31-year periodicity for the 12-month SPI. The results provide insights into the typical climatic conditions in Poland, with strong seasonality in precipitation. The study highlighted that short-term extreme droughts, represented by the 3-month SPI, are often caused by anticyclonic situations with high-pressure wedges Ka and Wa, and anticyclonic West as observed in 52.3% of cases. These findings are crucial for understanding the spatial and temporal variability of short and long-term extreme droughts in Central Europe, particularly for the agriculture sector dominant in the northern part of the analyzed region, where drought frequency is highest.

Keywords: atmospheric circulation, drought, precipitation, SPI, the Upper Vistula Basin

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660 Evaluation of the Relations between Childhood Trauma and Dissociative Experiences, Self-Perception, and Early Maladaptive Schemes in Sexual Assault Convicts

Authors: Safak Akdemir

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The main purpose of this research is to evaluate the relationships between childhood traumas and dissociative experiences, self-perceptions and early maladaptive schemas in male convicts convicted of sexual assault crimes in prison. In our study, male convicts in prison for the crime of sexual assault constitute the experimental group, and the participants matched with this experimental group in terms of education, age and gender constitute the control group. The experimental group of the research consists of 189 male individuals who are convicted in the Ministry of Justice, General Directorate of Prisons, Istanbul/Maltepe L Type Closed Prison. The control group of this study consists of 147 adult males matched with the experimental group in terms of age, gender and education parameters. A total of 336 adult male individuals are included in the sample of this study. 46% of the experimental group were convicted of only sexual assault, 54% of them were convicted of both sexual assault and murder, injury and drug crimes. Total of five data collection tools, namely the Personal Information Form created by S. A. & E. O., Childhood Trauma Questionnaire (CTQ), the Dissociative Experiences Scale (DES), the Rosenberg Self-Esteem Scale (RSES), and the Young Schema Questionnaire-Short Form (YSQ-SF3), were completed. DES cut-off score of 99 (52.39%) of 189 convicts in the experimental group and 12 (8.17%) of 147 people in the control group was found to be 30 and above, and this result indicates the presence of pathological dissociative experiences. 180 (95.23%) of the sexual assault convicts in the experimental group had at least one childhood trauma, 154 (81.48%) were emotional neglect, 140 (74.07%) were emotional abuse, 121 (64.02%) were physical neglect, 91 (4814%) physical abuse and 70 (37.03%) sexual abuse. 168 (88.88%) of the experimental group reported multiple type of trauma and 12 (6.34%) reported single type of trauma. While the childhood traumas, isolation, abandonment and emotional deprivation schema levels of the convicts with a DES cut-off score of 30 and above are higher than the convicts with a DES cut-off score of 30 and above, their self-esteem is lower than this group. Experimental group while childhood traumas, dissociative experiences and early maladaptive schemas are higher than the control group, their self-esteem levels are lower. Dissociative experiences, abandonment and emotional deprivation early maladaptive schemas are more common in convicts aged between 18-30 years compared to convicts aged 31 and over. In addition, dissociative experiences and early maladaptive schemas of male convicts who reported physical and sexual abuse were higher than those who did not report physical and sexual abuse, while their self-esteem was at a lower level. As a result, in terms of psychotraumatology and clinical forensic psychology, dissociative disorders developed under the influence of chronic childhood traumas, with clinical interviews and psychometric measurements to be made in terms of forensic psychiatry; it is of fundamental importance to evaluate it in terms of neurosis-psychosis distinction, disability retirement, custody, malpractice, criminal and legal capacity criteria.

Keywords: crime, sexual assault, criminology, rape crimes, dissocitative disorders, maladative schemas

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659 Fear of Gender-Based Crime and Women Empowerment: An Empirical Study among the Urban Residents of Bangladesh

Authors: Mohammad Ashraful Alam, Biro Judit

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Fear of gender-based crime and fear of crime victimization for women is a major concern in the urban areas of Bangladesh. Based on the recent data from various human rights organizations and international literature the study found that gender-based crime especially sexual assault and rape are increasing in Bangladesh at a significant rate in comparison to other countries. The major focus of the study was to identify the relationship between fear of gender-based crime and women empowerment. To explore the fact the study followed the mixed methodological approach comprising with quantitative and qualitative methods and used secondary information from national and international sources. Corresponding global pictures the present study found that gender, age, complexion, social position, and ethnicity were more common factors of sexual assault and victimization in Bangladesh which lead to women become more fearful about crime victimization than men. Fear of gender-based crime traumatizes women which leads to withdrawal of their non-essential everyday works and some time from the essential works based on their social position, financial status, and social honor in the society. The increasing crime rate also increases the propensity to fear of criminal victimization, traumatization, and feeling of helplessness which make them vulnerable. The patriarchal culture and practices in Bangladesh based on religious culture and established social norms women always feel defenseless therefore they withdraw themselves from various social activities and own interest. Women who have already victimized feel more fear and become traumatized, and who do not victimize yet but know the severity of victimization from the media and others’ have the feeling of fear of crime. Women who find themselves as weak bonding and low networks with their neighbors and living for a short duration have a feeling of more fear and avoid visiting a certain place in a certain time and avoid some social activities. The study found the young women have more possibilities to become victimized through the feeling of fear of crime is higher among elderly women than young. Though women feel fear of all kinds of crime but usually all aged women are more fearful of sexual assault and rape than other violent crimes. Therefore, elderly women and another person in the family does not allow younger girls to go and involve outside activities to secure their family status. On the other hand, fear of crime in public transport is more common to all aged women at a higher level and sometimes they compromise their freedom, independence, financial opportunities, the job only to avoid the perceived threat, and save their social and cultural honor. The study also explores that fear of crime does not always depend on crime rate but the crime news, the severity of the crime, delay justice, the ineffectiveness of police, bail of criminals, corruption and political favoritism, etc. Finally, the study shows that the fear of gender-based crime and violence is working as a potential barrier to ensuring women's empowerment in Bangladesh.

Keywords: compromise personal freedom, fear of crime, fear of gender-based crime, fear of violent crime victimization, rape, sexual assaults, withdrawal from regular activities, women empowerment

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658 Environmental Impact of Pallets in the Supply Chain: Including Logistics and Material Durability in a Life Cycle Assessment Approach

Authors: Joana Almeida, Kendall Reid, Jonas Bengtsson

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Pallets are devices that are used for moving and storing freight and are nearly omnipresent in supply chains. The market is dominated by timber pallets, with plastic being a common alternative. Either option underpins the use of important resources (oil, land, timber), the emission of greenhouse gases and additional waste generation in most supply chains. This study uses a dynamic approach to the life cycle assessment (LCA) of pallets. It demonstrates that what ultimately defines the environmental burden of pallets in the supply chain is how often the length of its lifespan, which depends on the durability of the material and on how pallets are utilized. This study proposes a life cycle assessment (LCA) of pallets in supply chains supported by an algorithm that estimates pallet durability in function of material resilience and of logistics. The LCA runs from cradle-to-grave, including raw material provision, manufacture, transport and end of life. The scope is representative of timber and plastic pallets in the Australian and South-East Asia markets. The materials included in this analysis are: -tropical mixed hardwood, unsustainably harvested in SE Asia; -certified softwood, sustainably harvested; -conventional plastic, a mix of virgin and scrap plastic; -recycled plastic pallets, 100% mixed plastic scrap, which are being pioneered by Re > Pal. The logistical model purports that more complex supply chains and rougher handling subject pallets to higher stress loads. More stress shortens the lifespan of pallets in function of their composition. Timber pallets can be repaired, extending their lifespan, while plastic pallets cannot. At the factory gate, softwood pallets have the lowest carbon footprint. Re > pal follows closely due to its burden-free feedstock. Tropical mixed hardwood and plastic pallets have the highest footprints. Harvesting tropical mixed hardwood in SE Asia often leads to deforestation, leading to emissions from land use change. The higher footprint of plastic pallets is due to the production of virgin plastic. Our findings show that manufacture alone does not determine the sustainability of pallets. Even though certified softwood pallets have lower carbon footprint and their lifespan can be extended by repair, the need for re-supply of materials and disposal of waste timber offsets this advantage. It also leads to most waste being generated among all pallets. In a supply chain context, Re > Pal pallets have the lowest footprint due to lower replacement and disposal needs. In addition, Re > Pal are nearly ‘waste neutral’, because the waste that is generated throughout their life cycle is almost totally offset by the scrap uptake for production. The absolute results of this study can be confirmed by progressing the logistics model, improving data quality, expanding the range of materials and utilization practices. Still, this LCA demonstrates that considering logistics, raw materials and material durability is central for sustainable decision-making on pallet purchasing, management and disposal.

Keywords: carbon footprint, life cycle assessment, recycled plastic, waste

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657 The Dependence of Carbonate Pore Geometry on Fossils: Examples from Zechstein, Poland

Authors: Adam Fheed

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Carbonate porosity can be deceptive in the aspect of hydrocarbon exploration due to pore geometry variations, which are to some extent controlled by fossils. Therefore, the main aim of this paper was to assess the dependence of pore geometry and reservoir quality on fossils. The Permian Zechstein Limestone (Ca1) carbonates from the Brońsko Reef, located on the Wolsztyn Ridge in West Poland, were examined. Seventy meters of drill cores were described along with well log examination and transmitted-light microscope research. The archival porosity-permeability data was utilized to calibrate the well logs and look for the potential petrophysical trends. Several organism assemblages were recognized in the reef. Its bottom was colonized by the branched bryozoans which were fragmented and dissolved leaving poorly connected molds. Subsequently, numerous bivalves and gastropods appeared and their shells were heavily dissolved to form huge, albeit poorly communicated caverns. Such pores were also typical for local brachiopod occurrences. Although the caverns were widespread, and probably linked to the meteoric dissolution or freshwater flushing, severe anhydrite cementation has destroyed the majority of pores. Close to the top of Ca1, near the center of the reef, the fossil-rich zone comprising fenestrate bryozoans, extremely abundant encrusting foraminifers, bivalves, brachiopods, gastropods and ostracods, was identified. The zone contained extremely frequent dissolution channels formed within former shells of foraminifers, which had previously encrusted the bryozoans. The deposition of Ca1 strata has ultimately terminated with a poorly porous and generally impermeable stromatolitic layer containing scarce fossils. In general, the permeability of the reef rocks studied turned out to be the highest under the presence of foraminifer-related channels. In such cases, it frequently approached 100 mD. The presence of channels and other pores gave the average effective porosity derived from shallow resistivity and helium porosimetry of around 16 and 18 %, respectively. The highest porosity (over 18 %), often co-occurring with relatively low permeability (chiefly below 20 mD) was noted for the bottommost zone of the reef, represented by branched bryozoans. This is probably owing to a large amount of unconnected bryozoan-related molds. It was concluded that fossils played a major role in porosity formation and controlled the pore geometry significantly. While the dissolution of bivalves and brachiopods resulted in cavernous porosity formation, numerous molds were typically related with the alteration of branched bryozoans, gastropods and ostracods. Importantly, the bendy dissolution channels after the encrusting foraminifers appeared to be decisive in improving reservoir quality – specifically when permeability is considered. Acknowledgment: The research was financed by the Polish National Science Centre’s project No. UMO-2016/23/N/ST10/00350.

Keywords: dissolution channels, fossils, Permian, porosity

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656 Optimization of the Jatropha curcas Supply Chain as a Criteria for the Implementation of Future Collection Points in Rural Areas of Manabi-Ecuador

Authors: Boris G. German, Edward Jiménez, Sebastián Espinoza, Andrés G. Chico, Ricardo A. Narváez

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The unique flora and fauna of The Galapagos Islands has leveraged a tourism-driven growth in the islands. Nonetheless, such development is energy-intensive and requires thousands of gallons of diesel each year for thermoelectric electricity generation. The needed transport of fossil fuels from the continent has generated oil spillages and affectations to the fragile ecosystem of the islands. The Zero Fossil Fuels initiative for The Galapagos proposed by the Ecuadorian government as an alternative to reduce the use of fossil fuels in the islands, considers the replacement of diesel in thermoelectric generators, by Jatropha curcas vegetable oil. However, the Jatropha oil supply cannot entirely cover yet the demand for electricity generation in Galapagos. Within this context, the present work aims to provide an optimization model that can be used as a selection criterion for approving new Jatropha Curcas collection points in rural areas of Manabi-Ecuador. For this purpose, existing Jatropha collection points in Manabi were grouped under three regions: north (7 collection points), center (4 collection points) and south (9 collection points). Field work was carried out in every region in order to characterize the collection points, to establish local Jatropha supply and to determine transportation costs. Data collection was complemented using GIS software and an objective function was defined in order to determine the profit associated to Jatropha oil production. The market price of both Jatropha oil and residual cake, were considered for the total revenue; whereas Jatropha price, transportation and oil extraction costs were considered for the total cost. The tonnes of Jatropha fruit and seed, transported from collection points to the extraction plant, were considered as variables. The maximum and minimum amount of the collected Jatropha from each region constrained the optimization problem. The supply chain was optimized using linear programming in order to maximize the profits. Finally, a sensitivity analysis was performed in order to find a profit-based criterion for the acceptance of future collection points in Manabi. The maximum profit reached a value of $ 4,616.93 per year, which represented a total Jatropha collection of 62.3 tonnes Jatropha per year. The northern region of Manabi had the biggest collection share (69%), followed by the southern region (17%). The criteria for accepting new Jatropha collection points in the rural areas of Manabi can be defined by the current maximum profit of the zone and by the variation in the profit when collection points are removed one at a time. The definition of new feasible collection points plays a key role in the supply chain associated to Jatropha oil production. Therefore, a mathematical model that assists decision makers in establishing new collection points while assuring profitability, contributes to guarantee a continued Jatropha oil supply for Galapagos and a sustained economic growth in the rural areas of Ecuador.

Keywords: collection points, Jatropha curcas, linear programming, supply chain

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655 Ensuring Safety in Fire Evacuation by Facilitating Way-Finding in Complex Buildings

Authors: Atefeh Omidkhah, Mohammadreza Bemanian

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The issue of way-finding earmarks a wide range of literature in architecture and despite the 50 year background of way-finding studies, it still lacks a comprehensive theory for indoor settings. Way-finding has a notable role in emergency evacuation as well. People in the panic situation of a fire emergency need to find the safe egress route correctly and in as minimum time as possible. In this regard the parameters of an appropriate way-finding are mentioned in the evacuation related researches albeit scattered. This study reviews the fire safety related literature to extract a way-finding related framework for architectural purposes of the design of a safe evacuation route. In this regard a research trend review in addition with applied methodological approaches review is conducted. Then by analyzing eight original researches related to way-finding parameters in fire evacuation, main parameters that affect way-finding in emergency situation of a fire incident are extracted and a framework was developed based on them. Results show that the issues related to exit route and emergency evacuation can be chased in task oriented studies of way-finding. This research trend aims to access a high-level framework and in the best condition a theory that has an explanatory capability to define differences in way-finding in indoor/outdoor settings, complex/simple buildings and different building types or transitional spaces. The methodological advances demonstrate the evacuation way-finding researches in line with three approaches that the latter one is the most up-to-date and precise method to research this subject: real actors and hypothetical stimuli as in evacuation experiments, hypothetical actors and stimuli as in agent-based simulations and real actors and semi-real stimuli as in virtual reality environment by adding multi-sensory simulation. Findings on data-mining of 8 sample of original researches in way-finding in evacuation indicate that emergency way-finding design of a building should consider two level of space cognition problems in the time of emergency and performance consequences of them in the built environment. So four major classes of problems in way-finding which are visual information deficiency, confusing layout configuration, improper navigating signage and demographic issues had been defined and discussed as the main parameters that should be provided with solutions in design and interior of a building. In the design phase of complex buildings, which face more reported problem in way-finding, it is important to consider the interior components regarding to the building type of occupancy and behavior of its occupants and determine components that tend to become landmarks and set the architectural features of egress route in line with the directions that they navigate people. Research on topological cognition of environmental and its effect on way-finding task in emergency evacuation is proposed for future.

Keywords: architectural design, egress route, way-finding, fire safety, evacuation

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654 Co-Evolution of Urban Lake System and Rapid Urbanization: Case of Raipur, Chhattisgarh

Authors: Kamal Agrawal, Ved Prakash Nayak, Akshay Patil

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Raipur is known as a city of water bodies. The city had around 200 man-made and natural lakes of varying sizes. These structures were constructed to collect rainwater and control flooding in the city. Due to the transition from community participation to state government, as well as rapid urbanisation, Raipur now has only about 80 lakes left. Rapid and unplanned growth has resulted in pollution, encroachment, and eutrophication of the city's lakes. The state government keeps these lakes in good condition by cleaning them and proposing lakefront developments. However, maintaining individual lakes is insufficient because urban lakes are not distinct entities. It is a system comprised of the lake, shore, catchment, and other components. While Urban lake system (ULS) is a combination of multiple such lake systems interacting in a complex urban setting. Thus, the project aims to propose a co-evolution model for urban lake systems (ULS) and rapid urbanization in Raipur. The goals are to comprehend the ULS and to identify elements and dimensions of urbanization that influence the ULS. Evaluate the impact of rapid urbanization on the ULS & vice versa in the study area. Determine how to maximize the positive impact while minimizing the negative impact identified in the study area. Propose short-, medium-, and long-term planning interventions to support the ULS's co-evolution with rapid urbanization. A complexity approach is used to investigate the ULS. It is a technique for understanding large, complex systems. A complex system is one with many interconnected and interdependent elements and dimensions. Thus, elements of ULS and rapid urbanization are identified through a literature study to evaluate statements of their impacts (Beneficial/ Adverse) on one another. Rapid urbanization has been identified as having elements such as demography, urban legislation, informal settlement, urban infrastructure, and tourism. Similarly, the catchment area of the lake, the lake's water quality, the water spread area, and lakefront developments are all being impacted by rapid urbanisation. These nine elements serve as parameters for the subsequent analysis. Elements are limited to physical parameters only. The city has designated a study area based on the definition provided by the National Plan for the Conservation of Aquatic Ecosystems. Three lakes are discovered within a one-kilometer radius, establishing a tiny urban lake system. Because the condition of a lake is directly related to the condition of its catchment area, the catchment area of these three lakes is delineated as the study area. Data is collected to identify impact statements, and the interdependence diagram generated between the parameters yields results in terms of interlinking between each parameter and their impact on the system as a whole. The planning interventions proposed for the ULS and rapid urbanisation co-evolution model include spatial proposals as well as policy recommendations for the short, medium, and long term. This study's next step will be to determine how to implement the proposed interventions based on the availability of resources, funds, and governance patterns.

Keywords: urban lake system, co-evolution, rapid urbanization, complex system

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653 Flux-Gate vs. Anisotropic Magneto Resistance Magnetic Sensors Characteristics in Closed-Loop Operation

Authors: Neoclis Hadjigeorgiou, Spyridon Angelopoulos, Evangelos V. Hristoforou, Paul P. Sotiriadis

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The increasing demand for accurate and reliable magnetic measurements over the past decades has paved the way for the development of different types of magnetic sensing systems as well as of more advanced measurement techniques. Anisotropic Magneto Resistance (AMR) sensors have emerged as a promising solution for applications requiring high resolution, providing an ideal balance between performance and cost. However, certain issues of AMR sensors such as non-linear response and measurement noise are rarely discussed in the relevant literature. In this work, an analog closed loop compensation system is proposed, developed and tested as a means to eliminate the non-linearity of AMR response, reduce the 1/f noise and enhance the sensitivity of magnetic sensor. Additional performance aspects, such as cross-axis and hysteresis effects are also examined. This system was analyzed using an analytical model and a P-Spice model, considering both the sensor itself as well as the accompanying electronic circuitry. In addition, a commercial closed loop architecture Flux-Gate sensor (calibrated and certified), has been used for comparison purposes. Three different experimental setups have been constructed for the purposes of this work, each one utilized for DC magnetic field measurements, AC magnetic field measurements and Noise density measurements respectively. The DC magnetic field measurements have been conducted in laboratory environment employing a cubic Helmholtz coil setup in order to calibrate and characterize the system under consideration. A high-accuracy DC power supply has been used for providing the operating current to the Helmholtz coils. The results were recorded by a multichannel voltmeter The AC magnetic field measurements have been conducted in laboratory environment employing a cubic Helmholtz coil setup in order to examine the effective bandwidth not only of the proposed system but also for the Flux-Gate sensor. A voltage controlled current source driven by a function generator has been utilized for the Helmholtz coil excitation. The result was observed by the oscilloscope. The third experimental apparatus incorporated an AC magnetic shielding construction composed of several layers of electric steel that had been demagnetized prior to the experimental process. Each sensor was placed alone and the response was captured by the oscilloscope. The preliminary experimental results indicate that closed loop AMR response presented a maximum deviation of 0.36% with respect to the ideal linear response, while the corresponding values for the open loop AMR system and the Fluxgate sensor reached 2% and 0.01% respectively. Moreover, the noise density of the proposed close loop AMR sensor system remained almost as low as the noise density of the AMR sensor itself, yet considerably higher than that of the Flux-Gate sensor. All relevant numerical data are presented in the paper.

Keywords: AMR sensor, chopper, closed loop, electronic noise, magnetic noise, memory effects, flux-gate sensor, linearity improvement, sensitivity improvement

Procedia PDF Downloads 404
652 Viscoelastic Behavior of Human Bone Tissue under Nanoindentation Tests

Authors: Anna Makuch, Grzegorz Kokot, Konstanty Skalski, Jakub Banczorowski

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Cancellous bone is a porous composite of a hierarchical structure and anisotropic properties. The biological tissue is considered to be a viscoelastic material, but many studies based on a nanoindentation method have focused on their elasticity and microhardness. However, the response of many organic materials depends not only on the load magnitude, but also on its duration and time course. Depth Sensing Indentation (DSI) technique has been used for examination of creep in polymers, metals and composites. In the indentation tests on biological samples, the mechanical properties are most frequently determined for animal tissues (of an ox, a monkey, a pig, a rat, a mouse, a bovine). However, there are rare reports of studies of the bone viscoelastic properties on microstructural level. Various rheological models were used to describe the viscoelastic behaviours of bone, identified in the indentation process (e. g Burgers model, linear model, two-dashpot Kelvin model, Maxwell-Voigt model). The goal of the study was to determine the influence of creep effect on the mechanical properties of human cancellous bone in indentation tests. The aim of this research was also the assessment of the material properties of bone structures, having in mind the energy aspects of the curve (penetrator loading-depth) obtained in the loading/unloading cycle. There was considered how the different holding times affected the results within trabecular bone.As a result, indentation creep (CIT), hardness (HM, HIT, HV) and elasticity are obtained. Human trabecular bone samples (n=21; mean age 63±15yrs) from the femoral heads replaced during hip alloplasty were removed and drained from alcohol of 1h before the experiment. The indentation process was conducted using CSM Microhardness Tester equipped with Vickers indenter. Each sample was indented 35 times (7 times for 5 different hold times: t1=0.1s, t2=1s, t3=10s, t4=100s and t5=1000s). The indenter was advanced at a rate of 10mN/s to 500mN. There was used Oliver-Pharr method in calculation process. The increase of hold time is associated with the decrease of hardness parameters (HIT(t1)=418±34 MPa, HIT(t2)=390±50 MPa, HIT(t3)= 313±54 MPa, HIT(t4)=305±54 MPa, HIT(t5)=276±90 MPa) and elasticity (EIT(t1)=7.7±1.2 GPa, EIT(t2)=8.0±1.5 GPa, EIT(t3)=7.0±0.9 GPa, EIT(t4)=7.2±0.9 GPa, EIT(t5)=6.2±1.8 GPa) as well as with the increase of the elastic (Welastic(t1)=4.11∙10-7±4.2∙10-8Nm, Welastic(t2)= 4.12∙10-7±6.4∙10-8 Nm, Welastic(t3)=4.71∙10-7±6.0∙10-9 Nm, Welastic(t4)= 4.33∙10-7±5.5∙10-9Nm, Welastic(t5)=5.11∙10-7±7.4∙10-8Nm) and inelastic (Winelastic(t1)=1.05∙10-6±1.2∙10-7 Nm, Winelastic(t2) =1.07∙10-6±7.6∙10-8 Nm, Winelastic(t3)=1.26∙10-6±1.9∙10-7Nm, Winelastic(t4)=1.56∙10-6± 1.9∙10-7 Nm, Winelastic(t5)=1.67∙10-6±2.6∙10-7)) reaction of materials. The indentation creep increased logarithmically (R2=0.901) with increasing hold time: CIT(t1) = 0.08±0.01%, CIT(t2) = 0.7±0.1%, CIT(t3) = 3.7±0.3%, CIT(t4) = 12.2±1.5%, CIT(t5) = 13.5±3.8%. The pronounced impact of creep effect on the mechanical properties of human cancellous bone was observed in experimental studies. While the description elastic-inelastic, and thus the Oliver-Pharr method for data analysis, may apply in few limited cases, most biological tissues do not exhibit elastic-inelastic indentation responses. Viscoelastic properties of tissues may play a significant role in remodelling. The aspect is still under an analysis and numerical simulations. Acknowledgements: The presented results are part of the research project founded by National Science Centre (NCN), Poland, no.2014/15/B/ST7/03244.

Keywords: bone, creep, indentation, mechanical properties

Procedia PDF Downloads 147
651 Surface Adjustments for Endothelialization of Decellularized Porcine Pericardium

Authors: M. Markova, E. Filova, O. Kaplan, R. Matejka, L. Bacakova

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The porcine pericardium is used as a material for cardiac and aortic valves substitutes. Current biological aortic heart valve prosthesis have a limited lifetime period because they undergo degeneration. In order to make them more biocompatible and prolong their lifetime it is necessary to reseed the decellularized prostheses with endothelial cells and with valve interstitial cells. The endothelialization of the prosthesis-surface may be supported by suitable chemical surface modification of the prosthesis. The aim of this study is to prepare bioactive fibrin layers which would both support endothelialization of porcine pericardium and enhance differentiation and maturation of the endothelial cells seeded. As a material for surface adjustments we used layers of fibrin with/without heparin and some of them with adsorbed or chemically bound FGF2, VEGF or their combination. Fibrin assemblies were prepared in 24-well cell culture plate and were seeded with HSVEC (Human Saphenous Vein Endothelial Cells) at a density of 20,000 cells per well in EGM-2 medium with 0.5% FS and without heparin, without FGF2 and without VEGF; medium was supplemented with aprotinin (200 U/mL). As a control, surface polystyrene (PS) was used. Fibrin was also used as homogeneous impregnation of the decellularized porcine pericardium throughout the scaffolds. Morphology, density, and viability of the seeded endothelial cells were observed from micrographs after staining the samples by LIVE/DEAD cytotoxicity/viability assay kit on the days 1, 3, and 7. Endothelial cells were immunocytochemically stained for proteins involved in cell adhesion, i.e. alphaV integrin, vinculin, and VE-cadherin, markers of endothelial cells differentiation and maturation, i.e. von Willebrand factor and CD31, and for extracellular matrix proteins typically produced by endothelial cells, i.e. type IV collagen and laminin. The staining intensities were subsequently quantified using a software. HSVEC cells grew on each of the prepared surfaces better than on control surface. They reached confluency. The highest cell densities were obtained on the surface of fibrin with heparin and both grow factors used together. Intensity of alphaV integrins staining was highest on samples with remained fibrin layer, i.e. on layers with lower cell densities, i.e. on fibrin without heparin. Vinculin staining was apparent, but was rather diffuse, on fibrin with both FGF2 and VEGF and on control PS. Endothelial cells on all samples were positively stained for von Willebrand factor and CD31. VE-cadherin receptors clusters were best developed on fibrin with heparin and growth factors. Significantly stronger staining of type IV collagen was observed on fibrin with heparin and both growth factors. Endothelial cells on all samples produced laminin-1. Decellularized pericardium was homogeneously filled with fibrin structures. These fibrin-modified pericardium samples will be further seeded with cells and cultured in a bioreactor. Fibrin layers with/without heparin and with adsorbed or chemically bound FGF2, VEGF or their combination are good surfaces for endothelialization of cardiovascular prostheses or porcine pericardium based heart valves. Supported by the Ministry of Health, grants No15-29153A and 15-32497A, and the Grant Agency of the Czech Republic, project No. P108/12/G108.

Keywords: aortic valves prosthesis, FGF2, heparin, HSVEC cells, VEGF

Procedia PDF Downloads 239
650 Methodological Approach for the Prioritization of Different Micro-Contaminants as Potential River Basin Specific Pollutants in the Upper Tisza River Watershed

Authors: Mihail Simion Beldean-Galea, Virginia Coman, Florina Copaciu, Mihaela Vlassa, Radu Mihaiescu, Adina Croitoru, Viorel Arghius, Modest Gertsiuk, Mikola Gertsiuk

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Taking into consideration the huge number of chemicals released into environment compartments a proper environmental risk assessment is difficult to predict due to the gap of legislation and improper toxicological assessment of chemicals compounds. In Romania as well as in many other countries from Europe, the chemical status of the water body is characterized taking into consideration the Water Framework Directive (WFD) and the substances listed in Annex X. This Annex includes 45 substances from different classes of organic compounds and heavy metals for which AA-EQS and MAC-EQS have been established. For other compounds which are not included in Annex X, different methodologies to prioritize chemicals for risk assessment and monitoring has been proposed. These methodologies take into account Predicted No-Effect Concentrations (PNECs) of different classes of chemicals compounds available from existing risk assessments or from read-across models for acute toxicity to the standard test organisms such as Daphnia magna and Selenastrum capricornutum. Our work presents the monitoring results of 30 priority substances including polyaromatic hydrocarbons, pesticides, halogenated compounds, plasticizers and heavy metals and other 34 substances from different classes of pesticides and pharmaceuticals which are not included on the list of priority substances, performed in the Upper Tisza River Watershed from Romania and Ukraine. The obtained monitoring data were used for the establishment of the list of more relevant pollutants in the studied area and to establish the potential river basin specific pollutants. For this purpose, two indicators such as the Frequency of exceedance and Extent of exceedance of Predicted no-Effect Concentration (PNEC) were evaluated. These two indicators are based on maximum environmental concentrations (MECs) of priority substances and for other pollutants is use statistically based averages of obtained measured concentration compared to the lowest PNEC thresholds. From the obtained results it can be concluded that polyaromatic hydrocarbon such as Fluoranthene, Benzo[a]pyrene, Benzo[b]fluorathene, benzo[k]fluoranthene, Benzo(g.h.i)perylene, Indeno(1.2.3-cd)-pyrene, heavy metals such as Cadmium, Lead and Nickel can be considered as river basin specific pollutants, their concentration exceeding the Annual Average EQS concentration. Other compounds such as estrone, estriol, 174-β estradiol, naproxen or some antibiotics (Penicillin G, Tetracycline or Ceftazidime) should be taken into account for a long monitoring, in some cases their concentration exceeding PNEC. Acknowledgements: This work is performed in the frame of NATO SfP Programme, Project no. 984440.

Keywords: prioritization, river basin specific pollutants, Tisza River, water framework directive

Procedia PDF Downloads 277
649 Forced Migrants in Israel and Their Impact on the Urban Structure of Southern Neighborhoods of Tel Aviv

Authors: Arnon Medzini, Lilach Lev Ari

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Migration, the driving force behind increased urbanization, has made cities much more diverse places to live in. Nearly one-fifth of all migrants live in the world’s 20 largest cities. In many of these global cities, migrants constitute over a third of the population. Many of contemporary migrants are in fact ‘forced migrants,’ pushed from their countries of origin due to political or ethnic violence and persecution or natural disasters. During the past decade, massive numbers of labor migrants and asylum seekers have migrated from African countries to Israel via Egypt. Their motives for leaving their countries of origin include ongoing and bloody wars in the African continent as well as corruption, severe conditions of poverty and hunger, and economic and political disintegration. Most of the African migrants came to Israel from Eritrea and Sudan as they saw Israel the closest natural geographic asylum to Africa; soon they found their way to the metropolitan Tel-Aviv area. There they concentrated in poor neighborhoods located in the southern part of the city, where they live under conditions of crowding, poverty, and poor sanitation. Today around 45,000 African migrants reside in these neighborhoods, and yet there is no legal option for expelling them due to dangers they might face upon returning to their native lands. Migration of such magnitude to the weakened neighborhoods of south Tel-Aviv can lead to the destruction of physical, social and human infrastructures. The character of the neighborhoods is changing, and the local population is the main victim. These local residents must bear the brunt of the failure of both authorities and the government to handle the illegal inhabitants. The extremely crowded living conditions place a heavy burden on the dilapidated infrastructures in the weakened areas where the refugees live and increase the distress of the veteran residents of the neighborhoods. Some problems are economic and some stem from damage to the services the residents are entitled to, others from a drastic decline in their standard of living. Even the public parks no longer serve the purpose for which they were originally established—the well-being of the public and the neighborhood residents; they have become the main gathering place for the infiltrators and a center of crime and violence. Based on secondary data analysis (for example: The Israel’s Population, Immigration and Border Authority, the hotline for refugees and migrants), the objective of this presentation is to discuss the effects of forced migration to Tel Aviv on the following tensions: between the local population and the immigrants; between the local population and the state authorities, and between human rights groups vis-a-vis nationalist local organizations. We will also describe the changes which have taken place in the urban infrastructure of the city of Tel Aviv, and discuss the efficacy of various Israeli strategic trajectories when handling human problems arising in the marginal urban regions where the forced migrant population is concentrated.

Keywords: African asylum seekers, forced migrants, marginal urban regions, urban infrastructure

Procedia PDF Downloads 227
648 Poly(Methyl Methacrylate) Degradation Products and Its in vitro Cytotoxicity Evaluation in NIH3T3 Cells

Authors: Lesly Y Carmona-Sarabia, Luisa Barraza-Vergara, Vilmalí López-Mejías, Wandaliz Torres-García, Maribella Domenech-Garcia, Madeline Torres-Lugo

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Biosensors are used in many applications providing real-time monitoring to treat long-term conditions. Thus, understanding the physicochemical properties and biological side effects on the skin of polymers (e. g., poly(methyl methacrylate), PMMA) employed in the fabrication of wearable biosensors is crucial for the selection of manufacturing materials within this field. The PMMA (hydrophobic and thermoplastic polymer) is commonly employed as a coating material or substrate in the fabrication of wearable devices. The cytotoxicityof PMMA (including residual monomers or degradation products) on the skin, in terms of cells and tissue, is required to prevent possible adverse effects (cell death, skin reactions, sensitization) on human health. Within this work, accelerated aging of PMMA (Mw ~ 15000) through thermal and photochemical degradation was under-taken. The accelerated aging of PMMA was carried out by thermal (200°C, 1h) and photochemical degradation (UV-Vis, 8-15d) adapted employing ISO protocols (ISO-10993-12, ISO-4892-1:2016, ISO-877-1:2009, ISO-188: 2011). In addition, in vitro cytotoxicity evaluation of PMMA degradation products was performed using NIH3T3 fibroblast cells to assess the response of skin tissues (in terms of cell viability) exposed with polymers utilized to manufacture wearable biosensors, such as PMMA. The PMMA (Mw ~ 15000) before and after accelerated aging experiments was characterized by thermal gravimetric analysis (TGA), differential scanning calorimetric (DSC), powder X-ray diffractogram (PXRD), and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) to determine and verify the successful degradation of this polymer under the specific conditions previously mention. The degradation products were characterized through nuclear magnetic resonance (NMR) to identify possible byproducts generated after the accelerated aging. Results demonstrated a percentage (%) weight loss between 1.5-2.2% (TGA thermographs) for PMMA after accelerated aging. The EDS elemental analysis reveals a 1.32 wt.% loss of carbon for PMMA after thermal degradation. These results might be associated with the amount (%) of PMMA degrade after the accelerated aging experiments. Furthermore, from the thermal degradation products was detected the presence of the monomer and methyl formate (low concentrations) and a low molecular weight radical (·COOCH3) in higher concentrations by NMR. In the photodegradation products, methyl formate was detected in higher concentrations. These results agree with the proposed thermal or photochemical degradation mechanisms found in the literature.1,2 Finally, significant cytotoxicity on the NIH3T3 cells was obtained for the thermal and photochemical degradation products. A decrease in cell viability by > 90% (stock solutions) was observed. It is proposed that the presence of byproducts (e.g. methyl formate or radicals such as ·COOCH₃) from the PMMA degradation might be responsible for the cytotoxicity observed in the NIH3T3 fibroblast cells. Additionally, experiments using skin models will be employed to compare with the NIH3T3 fibroblast cells model.

Keywords: biosensors, polymer, skin irritation, degradation products, cell viability

Procedia PDF Downloads 115
647 Hydrogeomatic System for the Economic Evaluation of Damage by Flooding in Mexico

Authors: Alondra Balbuena Medina, Carlos Diaz Delgado, Aleida Yadira Vilchis Fránces

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In Mexico, each year news is disseminated about the ravages of floods, such as the total loss of housing, damage to the fields; the increase of the costs of the food, derived from the losses of the harvests, coupled with health problems such as skin infection, etc. In addition to social problems such as delinquency, damage in education institutions and the population in general. The flooding is a consequence of heavy rains, tropical storms and or hurricanes that generate excess water in drainage systems that exceed its capacity. In urban areas, heavy rains can be one of the main factors in causing flooding, in addition to excessive precipitation, dam breakage, and human activities, for example, excessive garbage in the strainers. In agricultural areas, these can hardly achieve large areas of cultivation. It should be mentioned that for both areas, one of the significant impacts of floods is that they can permanently affect the livelihoods of many families, cause damage, for example in their workplaces such as farmlands, commercial or industry areas and where services are provided. In recent years, Information and Communication Technologies (ICT) have had an accelerated development, being reflected in the growth and the exponential evolution of the innovation giving; as a result, the daily generation of new technologies, updates, and applications. Innovation in the development of Information Technology applications has impacted on all areas of human activity. They influence all the orders of life of individuals, reconfiguring the way of perceiving and analyzing the world such as, for instance, interrelating with people as individuals and as a society, in the economic, political, social, cultural, educational, environmental, etc. Therefore the present work describes the creation of a system of calculation of flood costs for housing areas, retail establishments and agricultural areas from the Mexican Republic, based on the use and application of geotechnical tools being able to be useful for the benefit of the sectors of public, education and private. To generate analysis of hydrometereologic affections and with the obtained results to realize the Geoinformatics tool was constructed from two different points of view: the geoinformatic (design and development of GIS software) and the methodology of flood damage validation in order to integrate a tool that provides the user the monetary estimate of the effects caused by the floods. With information from the period 2000-2014, the functionality of the application was corroborated. For the years 2000 to 2009 only the analysis of the agricultural and housing areas was carried out, incorporating for the commercial establishment's information of the period 2010 - 2014. The method proposed for the resolution of this research project is a fundamental contribution to society, in addition to the tool itself. Therefore, it can be summarized that the problems that are in the physical-geographical environment, conceiving them from the point of view of the spatial analysis, allow to offer different alternatives of solution and also to open up slopes towards academia and research.

Keywords: floods, technological innovation, monetary estimation, spatial analysis

Procedia PDF Downloads 197
646 Vision and Challenges of Developing VR-Based Digital Anatomy Learning Platforms and a Solution Set for 3D Model Marking

Authors: Gizem Kayar, Ramazan Bakir, M. Ilkay Koşar, Ceren U. Gencer, Alperen Ayyildiz

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Anatomy classes are crucial for general education of medical students, whereas learning anatomy is quite challenging and requires memorization of thousands of structures. In traditional teaching methods, learning materials are still based on books, anatomy mannequins, or videos. This results in forgetting many important structures after several years. However, more interactive teaching methods like virtual reality, augmented reality, gamification, and motion sensors are becoming more popular since such methods ease the way we learn and keep the data in mind for longer terms. During our study, we designed a virtual reality based digital head anatomy platform to investigate whether a fully interactive anatomy platform is effective to learn anatomy and to understand the level of teaching and learning optimization. The Head is one of the most complicated human anatomy structures, with thousands of tiny, unique structures. This makes the head anatomy one of the most difficult parts to understand during class sessions. Therefore, we developed a fully interactive digital tool with 3D model marking, quiz structures, 2D/3D puzzle structures, and VR support so as to integrate the power of VR and gamification. The project has been developed in Unity game engine with HTC Vive Cosmos VR headset. The head anatomy 3D model has been selected with full skeletal, muscular, integumentary, head, teeth, lymph, and vein system. The biggest issue during the development was the complexity of our model and the marking of it in the 3D world system. 3D model marking requires to access to each unique structure in the counted subsystems which means hundreds of marking needs to be done. Some parts of our 3D head model were monolithic. This is why we worked on dividing such parts to subparts which is very time-consuming. In order to subdivide monolithic parts, one must use an external modeling tool. However, such tools generally come with high learning curves, and seamless division is not ensured. Second option was to integrate tiny colliders to all unique items for mouse interaction. However, outside colliders which cover inner trigger colliders cause overlapping, and these colliders repel each other. Third option is using raycasting. However, due to its own view-based nature, raycasting has some inherent problems. As the model rotate, view direction changes very frequently, and directional computations become even harder. This is why, finally, we studied on the local coordinate system. By taking the pivot point of the model into consideration (back of the nose), each sub-structure is marked with its own local coordinate with respect to the pivot. After converting the mouse position to the world position and checking its relation with the corresponding structure’s local coordinate, we were able to mark all points correctly. The advantage of this method is its applicability and accuracy for all types of monolithic anatomical structures.

Keywords: anatomy, e-learning, virtual reality, 3D model marking

Procedia PDF Downloads 69
645 Evaluation of Bagh Printing Motifs and Processes of Madhya Pradesh: From Past to Contemporary

Authors: Kaveri Dutta, Ratna Sharma

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Indian traditional textile is a synthesis of various cultures. Art and crafts of a country showcases the rich cultural and artistic history of that nation. Prehistorically Indian handicrafts were basically made for day to day use; the yearning for aesthetic application soon saw the development of flooding designs and motifs. Similarly, Bagh print a traditional hand block Print with natural colours an Indian handicraft practiced in Bagh, Madhya Pradesh(India). Bagh print has its roots in Sindh, which is now a part of Pakistan. The present form of Bagh printing actually started in 1962 when the craftsmen migrated from Manavar to the neighboring town of Bagh situated in Madhya Pradesh and hence Bagh has always been associated with this printing style. Bagh printing basically involved blocks that are carved onto motifs that represent flora such as Jasmine, Mushroom leheriya and so on. There are some prints that were inspired by the jaali work that embellished the Taj Mahal and various other forts. Inspiration is also drawn from the landscapes and geometrical figures. The motifs evoke various moods in the serenity of the prints and that is the catchy element of Bagh prints. The development in this traditional textile is as essential as in another field. Nowadays fashion trends are fragile and innovative changes over existing fashion field in the short span is the demand of times. We must make efforts to preserve this cultural heritage of arts and crafts and this is done either by documenting the various ancient traditions or by making a blend of it. Since this craft is well known over the world, but the need is to document the original motif, fabric, technology and colors used in contemporary fashion. Hence keeping above points in mind this study on bagh print textiles of Madhya Pradesh work has been formulated. The information incorporated in the paper was based on secondary data taken from relevant books, journals, museum visit and articles. Besides for the demographic details and working profile of the artisans dealt with printing, an interview schedule was carried out in three regions of Madhya Pradesh. This work of art was expressed in Cotton fabric. For this study selected traditional motifs for Bang printing was used. Some of the popular traditional Bagh motifs are Jasmine, Mushroom leheriya, geometrical figures and jaali work. The Bagh printed cotton fabrics were developed into a range of men’s ethic wear in combination with embroideries from Rajasthan. Products developed were bandhgala jackets, kurtas, serwani and dupattas. From the present study, it can be observed that the embellished traditional Bang printed range of ethnic men’s wear resulted in the fresh and colourful pattern. The embroidered Bagh printed cotton fabric also created a huge change in a positive way among artisans of the three regions.

Keywords: art and craft of Madhya Pradesh, evolution of printing in India, history of Bagh printing, sources of inspiration

Procedia PDF Downloads 334
644 A Sociological Study of the Potential Role of Retired Soldiers in the Post War Development and Reconstruction in Sri Lanka

Authors: Amunupura Kiriwandeiye Gedara, Asintha Saminda Gnanaratne

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The security forces can be described as a workforce that goes beyond the role of ensuring the national security and contributes to the development process of the country. Soldiers are following combatant training courses during their tenure, they are equipped with a variety of vocational training courses to satisfy the needs of the army, to equip them with vocational training capabilities to achieve the development and reconstruction goals of the country as well as for the betterment of society in the event of emergencies. But with retirement, their relationship with the military is severed, and they are responsible for the future of their lives. The main purpose of this study was to examine how such professional capabilities can contribute to the development of the country, the current socio-economic status of the retired soldiers, and the current application of the vocational training skills they have mastered in the army to develop and rebuild the country in an effective manner. After analyzing the available research literature related to this field, a conceptual framework was developed and according to qualitative research methodology, and data obtained from Case studies and interviews are analyzed by using thematic analysis. Factors influencing early retirement include a lack of understanding of benefits, delays in promotions, not being properly evaluated for work, getting married on hasty decisions, and not having enough time to spend on family and household chores. Most of the soldiers are not aware about various programs and benefits available to retirees. They do not have a satisfactory attitude towards the retirement guidance they receive from the army at the time of retirement. Also, due to the lack of understanding about how to use their vocational capabilities successfully pursue their retirement life, the majority of people are employed in temporary jobs, and some are successful in post-retirement life due to their successful use of training received. Some live on pensions without engaging in any income-generating activities, and those who retire after 12 years of service are facing severe economic hardships as they do not get pensions. Although they have received training in various fields, they do not use them for their benefit due to lack of proper guidance. Although the government implements programs, they are not clearly aware of them. Barriers to utilization of training include an absence of a system to identify the professional skills of retired soldiers, interest in civil society affairs, exploration of opportunities in the civil and private sectors, and politicization of services. If they are given the opportunity, they will be able to contribute to the development and reconstruction process. The findings of the study further show that it has many social, economic, political, and psychological benefits not only for individuals but also for a country. Entrepreneurship training for all retired soldiers, improving officers' understanding, streamlining existing mechanisms, creating new mechanisms, setting up a separate unit for retirees, and adapting them to civil society, private and non-governmental contributions, and training courses can be identified as potential means to improve the current situation.

Keywords: development, reconstruction, retired soldiers, vocational capabilities

Procedia PDF Downloads 102
643 Development of a Risk Governance Index and Examination of Its Determinants: An Empirical Study in Indian Context

Authors: M. V. Shivaani, P. K. Jain, Surendra S. Yadav

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Risk management has been gaining extensive focus from international organizations like Committee of Sponsoring Organizations and Financial Stability Board, and, the foundation of such an effective and efficient risk management system lies in a strong risk governance structure. In view of this, an attempt (perhaps a first of its kind) has been made to develop a risk governance index, which could be used as proxy for quality of risk governance structures. The index (normative framework) is based on eleven variables, namely, size of board, board diversity in terms of gender, proportion of executive directors, executive/non-executive status of chairperson, proportion of independent directors, CEO duality, chief risk officer (CRO), risk management committee, mandatory committees, voluntary committees and existence/non-existence of whistle blower policy. These variables are scored on a scale of 1 to 5 with the exception of the variables, namely, status of chairperson and CEO duality (which have been scored on a dichotomous scale with the score of 3 or 5). In case there is a legal/statutory requirement in respect of above-mentioned variables and there is a non-compliance with such requirement a score of one has been envisaged. Though there is no legal requirement, for the larger part of study, in context of CRO, risk management committee and whistle blower policy, still a score of 1 has been assigned in the event of their non-existence. Recognizing the importance of these variables in context of risk governance structure and the fact that the study basically focuses on risk governance, the absence of these variables has been equated to non-compliance with a legal/statutory requirement. Therefore, based on this the minimum score is 15 and the maximum possible is 55. In addition, an attempt has been made to explore the determinants of this index. For this purpose, the sample consists of non-financial companies (429) that constitute S&P CNX500 index. The study covers a 10 years period from April 1, 2005 to March 31, 2015. Given the panel nature of data, Hausman test was applied, and it suggested that fixed effects regression would be appropriate. The results indicate that age and size of firms have significant positive impact on its risk governance structures. Further, post-recession period (2009-2015) has witnessed significant improvement in quality of governance structures. In contrast, profitability (positive relationship), leverage (negative relationship) and growth (negative relationship) do not have significant impact on quality of risk governance structures. The value of rho indicates that about 77.74% variation in risk governance structures is due to firm specific factors. Given the fact that each firm is unique in terms of its risk exposure, risk culture, risk appetite, and risk tolerance levels, it appears reasonable to assume that the specific conditions and circumstances that a company is beset with, could be the biggest determinants of its risk governance structures. Given the recommendations put forth in the paper (particularly for regulators and companies), the study is expected to be of immense utility in an important yet neglected aspect of risk management.

Keywords: corporate governance, ERM, risk governance, risk management

Procedia PDF Downloads 234
642 Waveguiding in an InAs Quantum Dots Nanomaterial for Scintillation Applications

Authors: Katherine Dropiewski, Michael Yakimov, Vadim Tokranov, Allan Minns, Pavel Murat, Serge Oktyabrsky

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InAs Quantum Dots (QDs) in a GaAs matrix is a well-documented luminescent material with high light yield, as well as thermal and ionizing radiation tolerance due to quantum confinement. These benefits can be leveraged for high-efficiency, room temperature scintillation detectors. The proposed scintillator is composed of InAs QDs acting as luminescence centers in a GaAs stopping medium, which also acts as a waveguide. This system has appealing potential properties, including high light yield (~240,000 photons/MeV) and fast capture of photoelectrons (2-5ps), orders of magnitude better than currently used inorganic scintillators, such as LYSO or BaF2. The high refractive index of the GaAs matrix (n=3.4) ensures light emitted by the QDs is waveguided, which can be collected by an integrated photodiode (PD). Scintillation structures were grown using Molecular Beam Epitaxy (MBE) and consist of thick GaAs waveguiding layers with embedded sheets of modulation p-type doped InAs QDs. An AlAs sacrificial layer is grown between the waveguide and the GaAs substrate for epitaxial lift-off to separate the scintillator film and transfer it to a low-index substrate for waveguiding measurements. One consideration when using a low-density material like GaAs (~5.32 g/cm³) as a stopping medium is the matrix thickness in the dimension of radiation collection. Therefore, luminescence properties of very thick (4-20 microns) waveguides with up to 100 QD layers were studied. The optimization of the medium included QD shape, density, doping, and AlGaAs barriers at the waveguide surfaces to prevent non-radiative recombination. To characterize the efficiency of QD luminescence, low temperature photoluminescence (PL) (77-450 K) was measured and fitted using a kinetic model. The PL intensity degrades by only 40% at RT, with an activation energy for electron escape from QDs to the barrier of ~60 meV. Attenuation within the waveguide (WG) is a limiting factor for the lateral size of a scintillation detector, so PL spectroscopy in the waveguiding configuration was studied. Spectra were measured while the laser (630 nm) excitation point was scanned away from the collecting fiber coupled to the edge of the WG. The QD ground state PL peak at 1.04 eV (1190 nm) was inhomogeneously broadened with FWHM of 28 meV (33 nm) and showed a distinct red-shift due to self-absorption in the QDs. Attenuation stabilized after traveling over 1 mm through the WG, at about 3 cm⁻¹. Finally, a scintillator sample was used to test detection and evaluate timing characteristics using 5.5 MeV alpha particles. With a 2D waveguide and a small area of integrated PD, the collected charge averaged 8.4 x10⁴ electrons, corresponding to a collection efficiency of about 7%. The scintillation response had 80 ps noise-limited time resolution and a QD decay time of 0.6 ns. The data confirms unique properties of this scintillation detector which can be potentially much faster than any currently used inorganic scintillator.

Keywords: GaAs, InAs, molecular beam epitaxy, quantum dots, III-V semiconductor

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641 The Professionalization of Teachers in the Context of the Development of a Future-Oriented Technical and Vocational Education and Training System in Egypt

Authors: Sherin Ahmed El-Badry Sadek

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In this research, it is scientifically examined what contribution the professionalization of teachers can make to the development of a future-oriented vocational education and training system in Egypt. For this purpose, a needs assessment of the Egyptian vocational training system with the central actors and prevailing structures forms the foundation of the study, which theoretically underpinned with the attempt to resolve to some extent the tension between Luhmann's systems theory approach and the actor-centered theory of professional teacher competence. The vocational education system, in particular, must be adaptable and flexible due to the rapidly changing qualification requirements. In view of the pace of technological progress and the associated market changes, vocational training is no longer to be understood only as an educational tool aimed at those who achieve poorer academic performance or are not motivated to take up a degree. Rather, it is to be understood as a cornerstone for the development of society, and international experience shows that it is the core of lifelong learning. But to what extent have the education systems been able to react to these changes in their political, social, and technological systems? And how effective and sustainable are these changes actually? The vocational training system, in particular, has a particular impact on other social systems, which is why the appropriate parameters with the greatest leverage must be identified and adapted. Even if systems and structures are highly relevant, teachers must not hide behind them and must instead strive to develop further and to constantly learn. Despite numerous initiatives and programs to reform vocational training in Egypt, including the EU-funded Technical and Vocational Education and Training (TVET) reform phase I and phase II, the fit of the skilled workers to the needs of the labor market is still insufficient. Surveys show that the majority of employers are very dissatisfied with the graduates that the vocational training system produces. The data was collected through guideline-based interviews with experts from the education system and relevant neighboring systems, which allowed me to reconstruct central in-depth structures, as well as patterns of action and interpretation, in order to subsequently feed these into a matrix of recommendations for action. These recommendations are addressed to different decision-makers and stakeholders and are intended to serve as an impetus for the sustainable improvement of the Egyptian vocational training system. The research findings have shown that education, and in particular vocational training, is a political field that is characterized by a high degree of complexity and which is embedded in a barely manageable, highly branched landscape of structures and actors. At the same time, the vocational training system is not only determined by endogenous factors but also increasingly shaped by the dynamics of the environment and the neighboring social subsystems, with a mutual dependency relationship becoming apparent. These interactions must be taken into account in all decisions, even if prioritization of measures and thus a clear sequence and process orientation are of great urgency.

Keywords: competence orientation, educational policies, education systems, expert interviews, globalization, organizational development, professionalization, systems theory, teacher training, TVET system, vocational training

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640 Modeling Driving Distraction Considering Psychological-Physical Constraints

Authors: Yixin Zhu, Lishengsa Yue, Jian Sun, Lanyue Tang

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Modeling driving distraction in microscopic traffic simulation is crucial for enhancing simulation accuracy. Current driving distraction models are mainly derived from physical motion constraints under distracted states, in which distraction-related error terms are added to existing microscopic driver models. However, the model accuracy is not very satisfying, due to a lack of modeling the cognitive mechanism underlying the distraction. This study models driving distraction based on the Queueing Network Human Processor model (QN-MHP). This study utilizes the queuing structure of the model to perform task invocation and switching for distracted operation and control of the vehicle under driver distraction. Based on the assumption of the QN-MHP model about the cognitive sub-network, server F is a structural bottleneck. The latter information must wait for the previous information to leave server F before it can be processed in server F. Therefore, the waiting time for task switching needs to be calculated. Since the QN-MHP model has different information processing paths for auditory information and visual information, this study divides driving distraction into two types: auditory distraction and visual distraction. For visual distraction, both the visual distraction task and the driving task need to go through the visual perception sub-network, and the stimuli of the two are asynchronous, which is called stimulus on asynchrony (SOA), so when calculating the waiting time for switching tasks, it is necessary to consider it. In the case of auditory distraction, the auditory distraction task and the driving task do not need to compete for the server resources of the perceptual sub-network, and their stimuli can be synchronized without considering the time difference in receiving the stimuli. According to the Theory of Planned Behavior for drivers (TPB), this study uses risk entropy as the decision criterion for driver task switching. A logistic regression model is used with risk entropy as the independent variable to determine whether the driver performs a distraction task, to explain the relationship between perceived risk and distraction. Furthermore, to model a driver’s perception characteristics, a neurophysiological model of visual distraction tasks is incorporated into the QN-MHP, and executes the classical Intelligent Driver Model. The proposed driving distraction model integrates the psychological cognitive process of a driver with the physical motion characteristics, resulting in both high accuracy and interpretability. This paper uses 773 segments of distracted car-following in Shanghai Naturalistic Driving Study data (SH-NDS) to classify the patterns of distracted behavior on different road facilities and obtains three types of distraction patterns: numbness, delay, and aggressiveness. The model was calibrated and verified by simulation. The results indicate that the model can effectively simulate the distracted car-following behavior of different patterns on various roadway facilities, and its performance is better than the traditional IDM model with distraction-related error terms. The proposed model overcomes the limitations of physical-constraints-based models in replicating dangerous driving behaviors, and internal characteristics of an individual. Moreover, the model is demonstrated to effectively generate more dangerous distracted driving scenarios, which can be used to construct high-value automated driving test scenarios.

Keywords: computational cognitive model, driving distraction, microscopic traffic simulation, psychological-physical constraints

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639 Reflections on the Trajectory of an Online Literature Cafe through Its Music and Arts Activities

Authors: Mariko Hara, Mari Aoki, Takako Ito, Masao Sugita

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Social distancing measures due to the COVID-19 crisis had a severe impact on music and art practices based in community settings. They had to re-think how to connect with their dispersed community using online tools. As the social distancing continues, there is an urgent need to investigate the possibilities of online community music and art practices. Are they sustainable actions that can have positive impacts on the community and the quality of lives of people over time? The Online Lindgren Café (hereafter ‘OLC’) is a monthly online literature event which started in June 2020. In the OLC, up to 14 members meet online to discuss the works of Astrid Lindgren and similar authors. Members come from various places in Japan and Norway, with a variety of expertise from music therapy, music education, psychotherapy, music sociology, storytelling, and theatre, and their family members join them. In these meetings, music and arts activities emerged in response to interests among the members. The resources and experiences of the members helped to develop these activities further. This paper first introduces one of the music and art activities in one specific event, a collaborative picture book-making with music, which was initiated and led by the second author. The third author chose the music, and the activity itself was recorded. This is followed by the description of a reflecting event, where the recording of the collaborative picture book-making activity was shared to facilitate further creations (drawings, haiku, and fabric weaving) as well as group reflections on the trajectories of the Online Lindgren Café. Finally, we will discuss the preliminary findings using the data collected at the reflecting event. Key findings suggest that the resource-driven approach of the OLC leveled the relationships among the intergenerational, multi-cultural, and interdisciplinary members. This enabled the members to set aside their professional and/or predominant identities, which allowed them to discover their own and others’ resources. The relaxed, unstructured, and liminal phenomenon at OLC can be regarded as a form of communitas, where members gain a sense of liberation and belonging in a different way from in-person communications. Participation from one’s home, as well as a video conferencing function that allowed the members to position themselves among the other participants in equal-sized windows, seems to have enabled members to feel safe to express themselves openly at the same time feel a sense of belonging. Furthermore, in the OLC, music and arts activities acted to inclusively connect and re-connect dispersed, intergenerational members with each other. For instance, in a music and drawing activity, music acted as a means for each member to engage in their own ‘drawing space’ while still feeling connected with the others. The positive experiences from these activities inspired the members to use similar approaches outside of the OLC. The finding suggests that, because of its resource-driven approach supported by the music and arts activities, the OLC could be developed further as a permeable and sustainable action even after any current social distancing measures are lifted.

Keywords: communitas, COVID-19, musical affordances, online community of practices, resource-driven approach

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638 Fischer Tropsch Synthesis in Compressed Carbon Dioxide with Integrated Recycle

Authors: Kanchan Mondal, Adam Sims, Madhav Soti, Jitendra Gautam, David Carron

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Fischer-Tropsch (FT) synthesis is a complex series of heterogeneous reactions between CO and H2 molecules (present in the syngas) on the surface of an active catalyst (Co, Fe, Ru, Ni, etc.) to produce gaseous, liquid, and waxy hydrocarbons. This product is composed of paraffins, olefins, and oxygenated compounds. The key challenge in applying the Fischer-Tropsch process to produce transportation fuels is to make the capital and production costs economically feasible relative to the comparative cost of existing petroleum resources. To meet this challenge, it is imperative to enhance the CO conversion while maximizing carbon selectivity towards the desired liquid hydrocarbon ranges (i.e. reduction in CH4 and CO2 selectivities) at high throughputs. At the same time, it is equally essential to increase the catalyst robustness and longevity without sacrificing catalyst activity. This paper focuses on process development to achieve the above. The paper describes the influence of operating parameters on Fischer Tropsch synthesis (FTS) from coal derived syngas in supercritical carbon dioxide (ScCO2). In addition, the unreacted gas and solvent recycle was incorporated and the effect of unreacted feed recycle was evaluated. It was expected that with the recycle, the feed rate can be increased. The increase in conversion and liquid selectivity accompanied by the production of narrower carbon number distribution in the product suggest that higher flow rates can and should be used when incorporating exit gas recycle. It was observed that this process was capable of enhancing the hydrocarbon selectivity (nearly 98 % CO conversion), reducing improving the carbon efficiency from 17 % to 51 % in a once through process and further converting 16 % CO2 to liquid with integrated recycle of the product gas stream and increasing the life of the catalyst. Catalyst robustness enhancement has been attributed to the absorption of heat of reaction by the compressed CO2 which reduced the formation of hotspots and the dissolution of waxes by the CO2 solvent which reduced the blinding of active sites. In addition, the recycling the product gas stream reduced the reactor footprint to one-fourth of the once through size and product fractionation utilizing the solvent effects of supercritical CO2 were realized. In addition to the negative CO2 selectivities, methane production was also inhibited and was limited to less than 1.5%. The effect of the process conditions on the life of the catalysts will also be presented. Fe based catalysts are known to have a high proclivity for producing CO2 during FTS. The data of the product spectrum and selectivity on Co and Fe-Co based catalysts as well as those obtained from commercial sources will also be presented. The measurable decision criteria were the increase in CO conversion at H2:CO ratio of 1:1 (as commonly found in coal gasification product stream) in supercritical phase as compared to gas phase reaction, decrease in CO2 and CH4 selectivity, overall liquid product distribution, and finally an increase in the life of the catalysts.

Keywords: carbon efficiency, Fischer Tropsch synthesis, low GHG, pressure tunable fractionation

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637 Sand Production Modelled with Darcy Fluid Flow Using Discrete Element Method

Authors: M. N. Nwodo, Y. P. Cheng, N. H. Minh

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In the process of recovering oil in weak sandstone formations, the strength of sandstones around the wellbore is weakened due to the increase of effective stress/load from the completion activities around the cavity. The weakened and de-bonded sandstone may be eroded away by the produced fluid, which is termed sand production. It is one of the major trending subjects in the petroleum industry because of its significant negative impacts, as well as some observed positive impacts. For efficient sand management therefore, there has been need for a reliable study tool to understand the mechanism of sanding. One method of studying sand production is the use of the widely recognized Discrete Element Method (DEM), Particle Flow Code (PFC3D) which represents sands as granular individual elements bonded together at contact points. However, there is limited knowledge of the particle-scale behavior of the weak sandstone, and the parameters that affect sanding. This paper aims to investigate the reliability of using PFC3D and a simple Darcy flow in understanding the sand production behavior of a weak sandstone. An isotropic tri-axial test on a weak oil sandstone sample was first simulated at a confining stress of 1MPa to calibrate and validate the parallel bond models of PFC3D using a 10m height and 10m diameter solid cylindrical model. The effect of the confining stress on the number of bonds failure was studied using this cylindrical model. With the calibrated data and sample material properties obtained from the tri-axial test, simulations without and with fluid flow were carried out to check on the effect of Darcy flow on bonds failure using the same model geometry. The fluid flow network comprised of every four particles connected with tetrahedral flow pipes with a central pore or flow domain. Parametric studies included the effects of confining stress, and fluid pressure; as well as validating flow rate – permeability relationship to verify Darcy’s fluid flow law. The effect of model size scaling on sanding was also investigated using 4m height, 2m diameter model. The parallel bond model successfully calibrated the sample’s strength of 4.4MPa, showing a sharp peak strength before strain-softening, similar to the behavior of real cemented sandstones. There seems to be an exponential increasing relationship for the bigger model, but a curvilinear shape for the smaller model. The presence of the Darcy flow induced tensile forces and increased the number of broken bonds. For the parametric studies, flow rate has a linear relationship with permeability at constant pressure head. The higher the fluid flow pressure, the higher the number of broken bonds/sanding. The DEM PFC3D is a promising tool to studying the micromechanical behavior of cemented sandstones.

Keywords: discrete element method, fluid flow, parametric study, sand production/bonds failure

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636 Mobile Phones, (Dis) Empowerment and Female Headed Households: Trincomalee, Sri Lanka

Authors: S. A. Abeykoon

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This study explores the empowerment potential of the mobile phone, the widely penetrated and greatly affordable communication technology in Sri Lanka, for female heads of households in Trincomalee District, Sri Lanka-an area recovering from the effects of a 30-year civil war and the 2004 Boxing Day Tsunami. It also investigates how the use of mobile phones by these women is shaped and appropriated by the gendered power relations and inequalities in their respective communities and by their socio-economic factors and demographic characteristics. This qualitative study is based on the epistemology of constructionism; interpretivist, functionalist and critical theory approaches; and the process of action research. The data collection was conducted from September 2014 to November 2014 in two Divisional Secretaries of the Trincomalee District, Sri Lanka. A total of 30 semi-structured depth interviews and six focus groups with the female heads of households of Sinhalese, Tamil and Muslim ethnicities were conducted using purposive, representative and snowball sampling methods. The Grounded theory method was used to analyze transcribed interviews, focus group discussions and field notes that were coded and categorized in accordance with the research questions and the theoretical framework of the study. The findings of the study indicated that the mobile phone has mainly enabled the participants to balance their income earning activities and family responsibilities and has been useful in maintaining their family and social relationships, occupational duties and in making decisions. Thus, it provided them a higher level of security, safety, reassurance and self-confidence in carrying out their daily activities. They also practiced innovative strategies for the effective and efficient use of their mobile expenses. Although participants whose husbands or relatives have migrated were more tended to use smart phones, mobile literacy level of the majority of the participants was at a lower level limited to making and receiving calls and using SMS (Short Message Service) services. However, their interaction with the mobile phone was significantly shaped by the gendered power relations and their multiple identities based on their ethnicity, religion, class, education, profession and age. Almost all the participants were precautious of giving their mobile numbers to and have been harassed with ‘nuisance calls’ from men. For many, ownership and use of their mobile phone was shaped and influenced by their children and migrated husbands. Although these practices limit their use of the technology, there were many instances that they challenged these gendered harassments. While man-made and natural destructions have disempowered and victimized the women in the Sri Lankan society, they have also liberated women making them stronger and transforming their agency and traditional gender roles. Therefore, their present position in society is reflected in their mobile phone use as they assist such women to be more self-reliant and liberated, yet making them disempowered at some time.

Keywords: mobile phone, gender power relations, empowerment, female heads of households

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635 Analytical, Numerical, and Experimental Research Approaches to Influence of Vibrations on Hydroelastic Processes in Centrifugal Pumps

Authors: Dinara F. Gaynutdinova, Vladimir Ya Modorsky, Nikolay A. Shevelev

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The problem under research is that of unpredictable modes occurring in two-stage centrifugal hydraulic pump as a result of hydraulic processes caused by vibrations of structural components. Numerical, analytical and experimental approaches are considered. A hypothesis was developed that the problem of unpredictable pressure decrease at the second stage of centrifugal pumps is caused by cavitation effects occurring upon vibration. The problem has been studied experimentally and theoretically as of today. The theoretical study was conducted numerically and analytically. Hydroelastic processes in dynamic “liquid – deformed structure” system were numerically modelled and analysed. Using ANSYS CFX program engineering analysis complex and computing capacity of a supercomputer the cavitation parameters were established to depend on vibration parameters. An influence domain of amplitudes and vibration frequencies on concentration of cavitation bubbles was formulated. The obtained numerical solution was verified using CFM program package developed in PNRPU. The package is based on a differential equation system in hyperbolic and elliptic partial derivatives. The system is solved by using one of finite-difference method options – the particle-in-cell method. The method defines the problem solution algorithm. The obtained numerical solution was verified analytically by model problem calculations with the use of known analytical solutions of in-pipe piston movement and cantilever rod end face impact. An infrastructure consisting of an experimental fast hydro-dynamic processes research installation and a supercomputer connected by a high-speed network, was created to verify the obtained numerical solutions. Physical experiments included measurement, record, processing and analysis of data for fast processes research by using National Instrument signals measurement system and Lab View software. The model chamber end face oscillated during physical experiments and, thus, loaded the hydraulic volume. The loading frequency varied from 0 to 5 kHz. The length of the operating chamber varied from 0.4 to 1.0 m. Additional loads weighed from 2 to 10 kg. The liquid column varied from 0.4 to 1 m high. Liquid pressure history was registered. The experiment showed dependence of forced system oscillation amplitude on loading frequency at various values: operating chamber geometrical dimensions, liquid column height and structure weight. Maximum pressure oscillation (in the basic variant) amplitudes were discovered at loading frequencies of approximately 1,5 kHz. These results match the analytical and numerical solutions in ANSYS and CFM.

Keywords: computing experiment, hydroelasticity, physical experiment, vibration

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