Search results for: metal parts
Commenced in January 2007
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Edition: International
Paper Count: 4773

Search results for: metal parts

273 Correlation between Defect Suppression and Biosensing Capability of Hydrothermally Grown ZnO Nanorods

Authors: Mayoorika Shukla, Pramila Jakhar, Tejendra Dixit, I. A. Palani, Vipul Singh

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Biosensors are analytical devices with wide range of applications in biological, chemical, environmental and clinical analysis. It comprises of bio-recognition layer which has biomolecules (enzymes, antibodies, DNA, etc.) immobilized over it for detection of analyte and transducer which converts the biological signal into the electrical signal. The performance of biosensor primarily the depends on the bio-recognition layer and therefore it has to be chosen wisely. In this regard, nanostructures of metal oxides such as ZnO, SnO2, V2O5, and TiO2, etc. have been explored extensively as bio-recognition layer. Recently, ZnO has the attracted attention of researchers due to its unique properties like high iso-electric point, biocompatibility, stability, high electron mobility and high electron binding energy, etc. Although there have been many reports on usage of ZnO as bio-recognition layer but to the authors’ knowledge, none has ever observed correlation between optical properties like defect suppression and biosensing capability of the sensor. Here, ZnO nanorods (ZNR) have been synthesized by a low cost, simple and low-temperature hydrothermal growth process, over Platinum (Pt) coated glass substrate. The ZNR have been synthesized in two steps viz. initially a seed layer was coated over substrate (Pt coated glass) followed by immersion of it into nutrient solution of Zinc nitrate and Hexamethylenetetramine (HMTA) with in situ addition of KMnO4. The addition of KMnO4 was observed to have a profound effect over the growth rate anisotropy of ZnO nanostructures. Clustered and powdery growth of ZnO was observed without addition of KMnO4, although by addition of it during the growth, uniform and crystalline ZNR were found to be grown over the substrate. Moreover, the same has resulted in suppression of defects as observed by Normalized Photoluminescence (PL) spectra since KMnO4 is a strong oxidizing agent which provides an oxygen rich growth environment. Further, to explore the correlation between defect suppression and biosensing capability of the ZNR Glucose oxidase (Gox) was immobilized over it, using physical adsorption technique followed by drop casting of nafion. Here the main objective of the work was to analyze effect of defect suppression over biosensing capability, and therefore Gox has been chosen as model enzyme, and electrochemical amperometric glucose detection was performed. The incorporation of KMnO4 during growth has resulted in variation of optical and charge transfer properties of ZNR which in turn were observed to have deep impact on biosensor figure of merits. The sensitivity of biosensor was found to increase by 12-18 times, due to variations introduced by addition of KMnO4 during growth. The amperometric detection of glucose in continuously stirred buffer solution was performed. Interestingly, defect suppression has been observed to contribute towards the improvement of biosensor performance. The detailed mechanism of growth of ZNR along with the overall influence of defect suppression on the sensing capabilities of the resulting enzymatic electrochemical biosensor and different figure of merits of the biosensor (Glass/Pt/ZNR/Gox/Nafion) will be discussed during the conference.

Keywords: biosensors, defects, KMnO4, ZnO nanorods

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272 Towards an Environmental Knowledge System in Water Management

Authors: Mareike Dornhoefer, Madjid Fathi

Abstract:

Water supply and water quality are key problems of mankind at the moment and - due to increasing population - in the future. Management disciplines like water, environment and quality management therefore need to closely interact, to establish a high level of water quality and to guarantee water supply in all parts of the world. Groundwater remediation is one aspect in this process. From a knowledge management perspective it is only possible to solve complex ecological or environmental problems if different factors, expert knowledge of various stakeholders and formal regulations regarding water, waste or chemical management are interconnected in form of a knowledge base. In general knowledge management focuses the processes of gathering and representing existing and new knowledge in a way, which allows for inference or deduction of knowledge for e.g. a situation where a problem solution or decision support are required. A knowledge base is no sole data repository, but a key element in a knowledge based system, thus providing or allowing for inference mechanisms to deduct further knowledge from existing facts. In consequence this knowledge provides decision support. The given paper introduces an environmental knowledge system in water management. The proposed environmental knowledge system is part of a research concept called Green Knowledge Management. It applies semantic technologies or concepts such as ontology or linked open data to interconnect different data and information sources about environmental aspects, in this case, water quality, as well as background material enriching an established knowledge base. Examples for the aforementioned ecological or environmental factors threatening water quality are among others industrial pollution (e.g. leakage of chemicals), environmental changes (e.g. rise in temperature) or floods, where all kinds of waste are merged and transferred into natural water environments. Water quality is usually determined with the help of measuring different indicators (e.g. chemical or biological), which are gathered with the help of laboratory testing, continuous monitoring equipment or other measuring processes. During all of these processes data are gathered and stored in different databases. Meanwhile the knowledge base needs to be established through interconnecting data of these different data sources and enriching its semantics. Experts may add their knowledge or experiences of previous incidents or influencing factors. In consequence querying or inference mechanisms are applied for the deduction of coherence between indicators, predictive developments or environmental threats. Relevant processes or steps of action may be modeled in form of a rule based approach. Overall the environmental knowledge system supports the interconnection of information and adding semantics to create environmental knowledge about water environment, supply chain as well as quality. The proposed concept itself is a holistic approach, which links to associated disciplines like environmental and quality management. Quality indicators and quality management steps need to be considered e.g. for the process and inference layers of the environmental knowledge system, thus integrating the aforementioned management disciplines in one water management application.

Keywords: water quality, environmental knowledge system, green knowledge management, semantic technologies, quality management

Procedia PDF Downloads 205
271 Phenotypic and Molecular Heterogeneity Linked to the Magnesium Transporter CNNM2

Authors: Reham Khalaf-Nazzal, Imad Dweikat, Paula Gimenez, Iker Oyenarte, Alfonso Martinez-Cruz, Domonik Muller

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Metal cation transport mediator (CNNM) gene family comprises 4 isoforms that are expressed in various human tissues. Structurally, CNNMs are complex proteins that contain an extracellular N-terminal domain preceding a DUF21 transmembrane domain, a ‘Bateman module’ and a C-terminal cNMP-binding domain. Mutations in CNNM2 cause familial dominant hypomagnesaemia. Growing evidence highlights the role of CNNM2 in neurodevelopment. Mutations in CNNM2 have been implicated in epilepsy, intellectual disability, schizophrenia, and others. In the present study, we aim to elucidate the function of CNNM2 in the developing brain. Thus, we present the genetic origin of symptoms in two family cohorts. In the first family, three siblings of a consanguineous Palestinian family in which parents are first cousins, and consanguinity ran over several generations, presented a varying degree of intellectual disability, cone-rod dystrophy, and autism spectrum disorder. Exome sequencing and segregation analysis revealed the presence of homozygous pathogenic mutation in the CNNM2 gene, the parents were heterozygous for that gene mutation. Magnesium blood levels were normal in the three children and their parents in several measurements. They had no symptoms of hypomagnesemia. The CNNM2 mutation in this family was found to locate in the CBS1 domain of the CNNM2 protein. The crystal structure of the mutated CNNM2 protein was not significantly different from the wild-type protein, and the binding of AMP or MgATP was not dramatically affected. This suggests that the CBS1 domain could be involved in pure neurodevelopmental functions independent of its magnesium-handling role, and this mutation could have affected a protein partner binding or other functions in this protein. In the second family, another autosomal dominant CNNM2 mutation was found to run in a large family with multiple individuals over three generations. All affected family members had hypomagnesemia and hypermagnesuria. Oral supplementation of magnesium did not increase the levels of magnesium in serum significantly. Some affected members of this family have defects in fine motor skills such as dyslexia and dyslalia. The detected mutation is located in the N-terminal part, which contains a signal peptide thought to be involved in the sorting and routing of the protein. In this project, we describe heterogenous clinical phenotypes related to CNNM2 mutations and protein functions. In the first family, and up to the authors’ knowledge, we report for the first time the involvement of CNNM2 in retinal photoreceptor development and function. In addition, we report the presence of a neurophenotype independent of magnesium status related to the CNNM2 protein mutation. Taking into account the different modes of inheritance and the different positions of the mutations within CNNM2 and its different structural and functional domains, it is likely that CNNM2 might be involved in a wide spectrum of neuropsychiatric comorbidities with considerable varying phenotypes.

Keywords: magnesium transport, autosomal recessive, autism, neurodevelopment, CBS domain

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270 Qualitative Characterization of Proteins in Common and Quality Protein Maize Corn by Mass Spectrometry

Authors: Benito Minjarez, Jesse Haramati, Yury Rodriguez-Yanez, Florencio Recendiz-Hurtado, Juan-Pedro Luna-Arias, Salvador Mena-Munguia

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During the last decades, the world has experienced a rapid industrialization and an expanding economy favoring a demographic boom. As a consequence, countries around the world have focused on developing new strategies related to the production of different farm products in order to meet future demands. Consequently, different strategies have been developed seeking to improve the major food products for both humans and livestock. Corn, after wheat and rice, is the third most important crop globally and is the primary food source for both humans and livestock in many regions around the globe. In addition, maize (Zea mays) is an important source of protein accounting for up to 60% of the daily human protein supply. Generally, many of the cereal grains have proteins with relatively low nutritional value, when they are compared with proteins from meat. In the case of corn, much of the protein is found in the endosperm (75 to 85%) and is deficient in two essential amino acids, lysine, and tryptophan. This deficiency results in an imbalance of amino acids and low protein content; normal maize varieties have less than half of the recommended amino acids for human nutrition. In addition, studies have shown that this deficiency has been associated with symptoms of growth impairment, anemia, hypoproteinemia, and fatty liver. Due to the fact that most of the presently available maize varieties do not contain the quality and quantity of proteins necessary for a balanced diet, different countries have focused on the research of quality protein maize (QPM). Researchers have characterized QPM noting that these varieties may contain between 70 to 100% more residues of the amino acids essential for animal and human nutrition, lysine, and tryptophan, than common corn. Several countries in Africa, Latin America, as well as China, have incorporated QPM in their agricultural development plan. Large parts of these countries have chosen a specific QPM variety based on their local needs and climate. Reviews have described the breeding methods of maize and have revealed the lack of studies on genetic and proteomic diversity of proteins in QPM varieties, and their genetic relationships with normal maize varieties. Therefore, molecular marker identification using tools such as mass spectrometry may accelerate the selection of plants that carry the desired proteins with high lysine and tryptophan concentration. To date, QPM maize lines have played a very important role in alleviating the malnutrition, and better characterization of these lines would provide a valuable nutritional enhancement for use in the resource-poor regions of the world. Thus, the objectives of this study were to identify proteins in QPM maize in comparison with a common maize line as a control.

Keywords: corn, mass spectrometry, QPM, tryptophan

Procedia PDF Downloads 270
269 Effects of Bipolar Plate Coating Layer on Performance Degradation of High-Temperature Proton Exchange Membrane Fuel Cell

Authors: Chen-Yu Chen, Ping-Hsueh We, Wei-Mon Yan

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Over the past few centuries, human requirements for energy have been met by burning fossil fuels. However, exploiting this resource has led to global warming and innumerable environmental issues. Thus, finding alternative solutions to the growing demands for energy has recently been driving the development of low-carbon and even zero-carbon energy sources. Wind power and solar energy are good options but they have the problem of unstable power output due to unpredictable weather conditions. To overcome this problem, a reliable and efficient energy storage sub-system is required in future distributed-power systems. Among all kinds of energy storage technologies, the fuel cell system with hydrogen storage is a promising option because it is suitable for large-scale and long-term energy storage. The high-temperature proton exchange membrane fuel cell (HT-PEMFC) with metallic bipolar plates is a promising fuel cell system because an HT-PEMFC can tolerate a higher CO concentration and the utilization of metallic bipolar plates can reduce the cost of the fuel cell stack. However, the operating life of metallic bipolar plates is a critical issue because of the corrosion phenomenon. As a result, in this work, we try to apply different coating layer on the metal surface and to investigate the protection performance of the coating layers. The tested bipolar plates include uncoated SS304 bipolar plates, titanium nitride (TiN) coated SS304 bipolar plates and chromium nitride (CrN) coated SS304 bipolar plates. The results show that the TiN coated SS304 bipolar plate has the lowest contact resistance and through-plane resistance and has the best cell performance and operating life among all tested bipolar plates. The long-term in-situ fuel cell tests show that the HT-PEMFC with TiN coated SS304 bipolar plates has the lowest performance decay rate. The second lowest is CrN coated SS304 bipolar plate. The uncoated SS304 bipolar plate has the worst performance decay rate. The performance decay rates with TiN coated SS304, CrN coated SS304 and uncoated SS304 bipolar plates are 5.324×10⁻³ % h⁻¹, 4.513×10⁻² % h⁻¹ and 7.870×10⁻² % h⁻¹, respectively. In addition, the EIS results indicate that the uncoated SS304 bipolar plate has the highest growth rate of ohmic resistance. However, the ohmic resistance with the TiN coated SS304 bipolar plates only increases slightly with time. The growth rate of ohmic resistances with TiN coated SS304, CrN coated SS304 and SS304 bipolar plates are 2.85×10⁻³ h⁻¹, 3.56×10⁻³ h⁻¹, and 4.33×10⁻³ h⁻¹, respectively. On the other hand, the charge transfer resistances with these three bipolar plates all increase with time, but the growth rates are all similar. In addition, the effective catalyst surface areas with all bipolar plates do not change significantly with time. Thus, it is inferred that the major reason for the performance degradation is the elevated ohmic resistance with time, which is associated with the corrosion and oxidation phenomena on the surface of the stainless steel bipolar plates.

Keywords: coating layer, high-temperature proton exchange membrane fuel cell, metallic bipolar plate, performance degradation

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268 Hedonic Pricing Model of Parboiled Rice

Authors: Roengchai Tansuchat, Wassanai Wattanutchariya, Aree Wiboonpongse

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Parboiled rice is one of the most important food grains and classified in cereal and cereal product. In 2015, parboiled rice was traded more than 14.34 % of total rice trade. The major parboiled rice export countries are Thailand and India, while many countries in Africa and the Middle East such as Nigeria, South Africa, United Arab Emirates, and Saudi Arabia, are parboiled rice import countries. In the global rice market, parboiled rice pricing differs from white rice pricing because parboiled rice is semi-processing product, (soaking, steaming and drying) which affects to their color and texture. Therefore, parboiled rice export pricing does not depend only on the trade volume, length of grain, and percentage of broken rice or purity but also depend on their rice seed attributes such as color, whiteness, consistency of color and whiteness, and their texture. In addition, the parboiled rice price may depend on the country of origin, and other attributes, such as certification mark, label, packaging, and sales locations. The objectives of this paper are to study the attributes of parboiled rice sold in different countries and to evaluate the relationship between parboiled rice price in different countries and their attributes by using hedonic pricing model. These results are useful for product development, and marketing strategies development. The 141 samples of parboiled rice were collected from 5 major parboiled rice consumption countries, namely Nigeria, South Africa, Saudi Arabia, United Arab Emirates and Spain. The physicochemical properties and optical properties, namely size and shape of seed, colour (L*, a*, and b*), parboiled rice texture (hardness, adhesiveness, cohesiveness, springiness, gumminess, and chewiness), nutrition (moisture, protein, carbohydrate, fat, and ash), amylose, package, country of origin, label are considered as explanatory variables. The results from parboiled rice analysis revealed that most of samples are classified as long grain and slender. The highest average whiteness value is the parboiled rice sold in South Africa. The amylose value analysis shows that most of parboiled rice is non-glutinous rice, classified in intermediate amylose content range, and the maximum value was found in United Arab Emirates. The hedonic pricing model showed that size and shape are the key factors to determine parboiled rice price statistically significant. In parts of colour, brightness value (L*) and red-green value (a*) are statistically significant, but the yellow-blue value (b*) is insignificant. In addition, the texture attributes that significantly affect to the parboiled rice price are hardness, adhesiveness, cohesiveness, and gumminess. The findings could help both parboiled rice miller, exporter and retailers formulate better production and marketing strategies by focusing on these attributes.

Keywords: hedonic pricing model, optical properties, parboiled rice, physicochemical properties

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267 Antibacterial Bioactive Glasses in Orthopedic Surgery and Traumatology

Authors: V. Schmidt, L. Janovák, N. Wiegand, B. Patczai, K. Turzó

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Large bone defects are not able to heal spontaneously. Bioactive glasses seem to be appropriate (bio)materials for bone reconstruction. Bioactive glasses are osteoconductive and osteoinductive, therefore, play a useful role in bony regeneration and repair. Because of their not optimal mechanical properties (e.g., brittleness, low bending strength, and fracture toughness), their applications are limited. Bioactive glass can be used as a coating material applied on metal surfaces. In this way -when using them as implants- the excellent mechanical properties of metals and the biocompatibility and bioactivity of glasses will be utilized. Furthermore, ion release effects of bioactive glasses regarding osteogenic and angiogenic responses have been shown. Silicate bioactive glasses (45S5 Bioglass) induce the release and exchange of soluble Si, Ca, P, and Na ions on the material surface. This will lead to special cellular responses inducing bone formation, which is favorable in the biointegration of the orthopedic prosthesis. The incorporation of other additional elements in the silicate network such as fluorine, magnesium, iron, silver, potassium, or zinc has been shown, as the local delivery of these ions is able to enhance specific cell functions. Although hip and knee prostheses present a high success rate, bacterial infections -mainly implant associated- are serious and frequent complications. Infection can also develop after implantation of hip prostheses, the elimination of which means more surgeries for the patient and additional costs for the clinic. Prosthesis-related infection is a severe complication of orthopedic surgery, which often causes prolonged illness, pain, and functional loss. While international efforts are made to reduce the risk of these infections, orthopedic surgical infections (SSIs) continue to occur in high numbers. It is currently estimated that up to 2.5% of primary hip and knee surgeries and up to 20% of revision arthroplasties are complicated by periprosthetic joint infection (PJIs). According to some authors, these numbers are underestimated, and they are also increasing. Staphylococcus aureus is the leading cause of both SSIs and PJIs, and the prevalence of methicillin-resistant S. aureus (MRSA) is on the rise, particularly in the United States. These deep infections lead to implant removal and consequently increase morbidity and mortality. The study targets this clinical problem using our experience so far with the Ag-doped polymer coatings on Titanium implants. Non-modified or modified (e.g., doped with antibacterial agents, like Ag) bioactive glasses could play a role in the prevention of infections or the therapy of infected tissues. Bioactive glasses have excellent biocompatibility, proved by in vitro cell culture studies of human osteoblast-like MG-63 cells. Ag-doped bioactive glass-scaffold has a good antibacterial ability against Escherichia coli and other bacteria. It may be concluded that these scaffolds have great potential in the prevention and therapy of implant-associated bone infection.

Keywords: antibacterial agents, bioactive glass, hip and knee prosthesis, medical implants

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266 Developing Offshore Energy Grids in Norway as Capability Platforms

Authors: Vidar Hepsø

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The energy and oil companies on the Norwegian Continental shelf come from a situation where each asset control and manage their energy supply (island mode) and move towards a situation where the assets need to collaborate and coordinate energy use with others due to increased cost and scarcity of electric energy sharing the energy that is provided. Currently, several areas are electrified either with an onshore grid cable or are receiving intermittent energy from offshore wind-parks. While the onshore grid in Norway is well regulated, the offshore grid is still in the making, with several oil and gas electrification projects and offshore wind development just started. The paper will describe the shift in the mindset that comes with operating this new offshore grid. This transition process heralds an increase in collaboration across boundaries and integration of energy management across companies, businesses, technical disciplines, and engagement with stakeholders in the larger society. This transition will be described as a function of the new challenges with increased complexity of the energy mix (wind, oil/gas, hydrogen and others) coupled with increased technical and organization complexity in energy management. Organizational complexity denotes an increasing integration across boundaries, whether these boundaries are company, vendors, professional disciplines, regulatory regimes/bodies, businesses, and across numerous societal stakeholders. New practices must be developed, made legitimate and institutionalized across these boundaries. Only parts of this complexity can be mitigated technically, e.g.: by use of batteries, mixing energy systems and simulation/ forecasting tools. Many challenges must be mitigated with legitimated societal and institutionalized governance practices on many levels. Offshore electrification supports Norway’s 2030 climate targets but is also controversial since it is exploiting the larger society’s energy resources. This means that new systems and practices must also be transparent, not only for the industry and the authorities, but must also be acceptable and just for the larger society. The paper report from ongoing work in Norway, participant observation and interviews in projects and people working with offshore grid development in Norway. One case presented is the development of an offshore floating windfarm connected to two offshore installations and the second case is an offshore grid development initiative providing six installations electric energy via an onshore cable. The development of the offshore grid is analyzed using a capability platform framework, that describes the technical, competence, work process and governance capabilities that are under development in Norway. A capability platform is a ‘stack’ with the following layers: intelligent infrastructure, information and collaboration, knowledge sharing & analytics and finally business operations. The need for better collaboration and energy forecasting tools/capabilities in this stack will be given a special attention in the two use cases that are presented.

Keywords: capability platform, electrification, carbon footprint, control rooms, energy forecsting, operational model

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265 A Machine Learning Approach for Assessment of Tremor: A Neurological Movement Disorder

Authors: Rajesh Ranjan, Marimuthu Palaniswami, A. A. Hashmi

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With the changing lifestyle and environment around us, the prevalence of the critical and incurable disease has proliferated. One such condition is the neurological disorder which is rampant among the old age population and is increasing at an unstoppable rate. Most of the neurological disorder patients suffer from some movement disorder affecting the movement of their body parts. Tremor is the most common movement disorder which is prevalent in such patients that infect the upper or lower limbs or both extremities. The tremor symptoms are commonly visible in Parkinson’s disease patient, and it can also be a pure tremor (essential tremor). The patients suffering from tremor face enormous trouble in performing the daily activity, and they always need a caretaker for assistance. In the clinics, the assessment of tremor is done through a manual clinical rating task such as Unified Parkinson’s disease rating scale which is time taking and cumbersome. Neurologists have also affirmed a challenge in differentiating a Parkinsonian tremor with the pure tremor which is essential in providing an accurate diagnosis. Therefore, there is a need to develop a monitoring and assistive tool for the tremor patient that keep on checking their health condition by coordinating them with the clinicians and caretakers for early diagnosis and assistance in performing the daily activity. In our research, we focus on developing a system for automatic classification of tremor which can accurately differentiate the pure tremor from the Parkinsonian tremor using a wearable accelerometer-based device, so that adequate diagnosis can be provided to the correct patient. In this research, a study was conducted in the neuro-clinic to assess the upper wrist movement of the patient suffering from Pure (Essential) tremor and Parkinsonian tremor using a wearable accelerometer-based device. Four tasks were designed in accordance with Unified Parkinson’s disease motor rating scale which is used to assess the rest, postural, intentional and action tremor in such patient. Various features such as time-frequency domain, wavelet-based and fast-Fourier transform based cross-correlation were extracted from the tri-axial signal which was used as input feature vector space for the different supervised and unsupervised learning tools for quantification of severity of tremor. A minimum covariance maximum correlation energy comparison index was also developed which was used as the input feature for various classification tools for distinguishing the PT and ET tremor types. An automatic system for efficient classification of tremor was developed using feature extraction methods, and superior performance was achieved using K-nearest neighbors and Support Vector Machine classifiers respectively.

Keywords: machine learning approach for neurological disorder assessment, automatic classification of tremor types, feature extraction method for tremor classification, neurological movement disorder, parkinsonian tremor, essential tremor

Procedia PDF Downloads 138
264 Interactivity as a Predictor of Intent to Revisit Sports Apps

Authors: Young Ik Suh, Tywan G. Martin

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Sports apps in a smartphone provide up-to-date information and fast and convenient access to live games. The market of sports apps has emerged as the second fastest growing app category worldwide. Further, many sports fans use their smartphones to know the schedule of sporting events, players’ position and bios, videos and highlights. In recent years, a growing number of scholars and practitioners alike have emphasized the importance of interactivity with sports apps, hypothesizing that interactivity plays a significant role in enticing sports apps users and that it is a key component in measuring the success of sports apps. Interactivity in sports apps focuses primarily on two functions: (1) two-way communication and (2) active user control, neither of which have been applicable through traditional mass media and communication technologies. Therefore, the purpose of this study is to examine whether the interactivity function on sports apps leads to positive outcomes such as intent to revisit. More specifically, this study investigates how three major functions of interactivity (i.e., two-way communication, active user control, and real-time information) influence the attitude of sports apps users and their intent to revisit the sports apps. The following hypothesis is proposed; interactivity functions will be positively associated with both attitudes toward sports apps and intent to revisit sports apps. The survey questionnaire includes four parts: (1) an interactivity scale, (2) an attitude scale, (3) a behavioral intention scale, and (4) demographic questions. Data are to be collected from ESPN apps users. To examine the relationships among the observed and latent variables and determine the reliability and validity of constructs, confirmatory factor analysis (CFA) is conducted. Structural equation modeling (SEM) is utilized to test hypothesized relationships among constructs. Additionally, this study compares the proposed interactivity model with a rival model to identify the role of attitude as a mediating factor. The findings of the current sports apps study provide several theoretical and practical contributions and implications by extending the research and literature associated with the important role of interactivity functions in sports apps and sports media consumption behavior. Specifically, this study may improve the theoretical understandings of whether the interactivity functions influence user attitudes and intent to revisit sports apps. Additionally, this study identifies which dimensions of interactivity are most important to sports apps users. From practitioners’ perspectives, this findings of this study provide significant implications. More entrepreneurs and investors in the sport industry need to recognize that high-resolution photos, live streams, and up-to-date stats are in the sports app, right at sports fans fingertips. The result will imply that sport practitioners may need to develop sports mobile apps that offer greater interactivity functions to attract sport fans.

Keywords: interactivity, two-way communication, active user control, real time information, sports apps, attitude, intent to revisit

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263 Potential Impacts of Climate Change on Hydrological Droughts in the Limpopo River Basin

Authors: Nokwethaba Makhanya, Babatunde J. Abiodun, Piotr Wolski

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Climate change possibly intensifies hydrological droughts and reduces water availability in river basins. Despite this, most research on climate change effects in southern Africa has focused exclusively on meteorological droughts. This thesis projects the potential impact of climate change on the future characteristics of hydrological droughts in the Limpopo River Basin (LRB). The study uses regional climate model (RCM) measurements (from the Coordinated Regional Climate Downscaling Experiment, CORDEX) and a combination of hydrological simulations (using the Soil and Water Assessment Tool Plus model, SWAT+) to predict the impacts at four global warming levels (GWLs: 1.5℃, 2.0℃, 2.5℃, and 3.0℃) under the RCP8.5 future climate scenario. The SWAT+ model was calibrated and validated with a streamflow dataset observed over the basin, and the sensitivity of model parameters was investigated. The performance of the SWAT+LRB model was verified using the Nash-Sutcliffe efficiency (NSE), Percent Bias (PBIAS), Root Mean Square Error (RMSE), and coefficient of determination (R²). The Standardized Precipitation Evapotranspiration Index (SPEI) and the Standardized Precipitation Index (SPI) have been used to detect meteorological droughts. The Soil Water Index (SSI) has been used to define agricultural drought, while the Water Yield Drought Index (WYLDI), the Surface Run-off Index (SRI), and the Streamflow Index (SFI) have been used to characterise hydrological drought. The performance of the SWAT+ model simulations over LRB is sensitive to the parameters CN2 (initial SCS runoff curve number for moisture condition II) and ESCO (soil evaporation compensation factor). The best simulation generally performed better during the calibration period than the validation period. In calibration and validation periods, NSE is ≤ 0.8, while PBIAS is ≥ ﹣80.3%, RMSE ≥ 11.2 m³/s, and R² ≤ 0.9. The simulations project a future increase in temperature and potential evapotranspiration over the basin, but they do not project a significant future trend in precipitation and hydrological variables. However, the spatial distribution of precipitation reveals a projected increase in precipitation in the southern part of the basin and a decline in the northern part of the basin, with the region of reduced precipitation projected to increase with GWLs. A decrease in all hydrological variables is projected over most parts of the basin, especially over the eastern part of the basin. The simulations predict meteorological droughts (i.e., SPEI and SPI), agricultural droughts (i.e., SSI), and hydrological droughts (i.e., WYLDI, SRI) would become more intense and severe across the basin. SPEI-drought has a greater magnitude of increase than SPI-drought, and agricultural and hydrological droughts have a magnitude of increase between the two. As a result, this research suggests that future hydrological droughts over the LRB could be more severe than the SPI-drought projection predicts but less severe than the SPEI-drought projection. This research can be used to mitigate the effects of potential climate change on basin hydrological drought.

Keywords: climate change, CORDEX, drought, hydrological modelling, Limpopo River Basin

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262 Implementation of Ecological and Energy-Efficient Building Concepts

Authors: Robert Wimmer, Soeren Eikemeier, Michael Berger, Anita Preisler

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A relatively large percentage of energy and resource consumption occurs in the building sector. This concerns the production of building materials, the construction of buildings and also the energy consumption during the use phase. Therefore, the overall objective of this EU LIFE project “LIFE Cycle Habitation” (LIFE13 ENV/AT/000741) is to demonstrate innovative building concepts that significantly reduce CO₂emissions, mitigate climate change and contain a minimum of grey energy over their entire life cycle. The project is being realised with the contribution of the LIFE financial instrument of the European Union. The ultimate goal is to design and build prototypes for carbon-neutral and “LIFE cycle”-oriented residential buildings and make energy-efficient settlements the standard of tomorrow in line with the EU 2020 objectives. To this end, a resource and energy-efficient building compound is being built in Böheimkirchen, Lower Austria, which includes 6 living units and a community area as well as 2 single family houses with a total usable floor surface of approximately 740 m². Different innovative straw bale construction types (load bearing and pre-fabricated non loadbearing modules) together with a highly innovative energy-supply system, which is based on the maximum use of thermal energy for thermal energy services, are going to be implemented. Therefore only renewable resources and alternative energies are used to generate thermal as well as electrical energy. This includes the use of solar energy for space heating, hot water and household appliances like dishwasher or washing machine, but also a cooking place for the community area operated with thermal oil as heat transfer medium on a higher temperature level. Solar collectors in combination with a biomass cogeneration unit and photovoltaic panels are used to provide thermal and electric energy for the living units according to the seasonal demand. The building concepts are optimised by support of dynamic simulations. A particular focus is on the production and use of modular prefabricated components and building parts made of regionally available, highly energy-efficient, CO₂-storing renewable materials like straw bales. The building components will be produced in collaboration by local SMEs that are organised in an efficient way. The whole building process and results are monitored and prepared for knowledge transfer and dissemination including a trial living in the residential units to test and monitor the energy supply system and to involve stakeholders into evaluation and dissemination of the applied technologies and building concepts. The realised building concepts should then be used as templates for a further modular extension of the settlement in a second phase.

Keywords: energy-efficiency, green architecture, renewable resources, sustainable building

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261 A Study of Status of Women by Incorporating Literacy and Employment in India and Some Selected States

Authors: Barnali Thakuria, Labananda Choudhury

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Gender equality and women’s empowerment is one of the components of eight Millennium Development Goal (MDG).Literacy and employment are the parameters which reflect the empowerment of women. But in a developing country like India, literacy and working status among the females are not satisfactory. Both literacy and employment technically can be measured by Literate Life Expectancy (LLE) and Working Life Expectancy (WLE).One can also combine both the factors literacy and working to get a better new measure. The proposed indicator can be called literate-working life expectancy (LWLE). LLE gives an average number of years a person lives in a literate state under current mortality and literacy conditions while WLE defined as average number of years a person lives in a working state if current mortality and working condition prevails. Similarly, LWLE gives number of expected years by a person living under both literate and working state. The situation of females cannot be figured out without comparing both the sexes. In the present paper an attempt has been made to estimate LLE and WLE in India along with some selected states from various zones of India namely Assam from the North-East, Gujarat from the West, Kerala from the South, Rajasthan from the North, Uttar Pradesh from the Central and West Bengal from the East respectively for both the sexes based on 2011 census. Furthermore, we have also developed a formula for a new indicator namely Literate-Working Life Expectancy (LWLE) and the proposed index has been applied in India and the selected states mentioned above for both males and females. Data has been extracted from SRS(Sample Registration System) based Abridged Life Table and Census of India. The computation of LLE follows the method developed by Lutz while WLE has followed the method developed by Saw Swee Hock. By combining both the factors literacy and employment, the new indicator LWLE also follows the method like LLE and WLE. Contrasted results have been found in different parts of India. The result shows that LLE at birth is highest(lowest) in the state Kerala(Uttar Pradesh) with 61.66 (39.51) years among the males. A similar situation is also observed among the females with 62.58 years and 25.11 years respectively. But male WLE at birth is highest (lowest) in Rajasthan(Kerala) with 37.11 (32.64) years. Highest female WLE at birth is also observed in Rajasthan with 23.51 years and the lowest is concentrated in Uttar Pradesh with 11.76 years. It is also found that Kerala’s performance is exceptionally good in terms of LWLE at birth while the lowest LWLE at birth prevails in the state Uttar Pradesh among the males. Female LWLE at birth is highest(lowest) in Kerala(Uttar Pradesh) with 19.73(4.77)years. The corresponding value of the index increases as the number of factors involved in the life expectancy decrease. It is found that women are lagging behind in terms of both literacy and employment. Findings of the study will help the planners to take necessary steps to improve the position of women.

Keywords: life expectancy, literacy, literate life expectancy, working life expectancy

Procedia PDF Downloads 404
260 Community Communications and Micro-Level Shifts: The Case of Video Volunteers’ IndiaUnheard Program

Authors: Pooja Ichplani, Archna Kumar, Jessica Mayberry

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Community Video (CV) is a participatory medium that has immense potential to strengthen community communications and amplify the voice of people for their empowerment. By building capacities especially of marginalized community groups and providing a platform to freely voice their ideas, CV endeavours to bring about shifts towards more participatory, bottom up development processes and greater power in the hands of the people, especially the disadvantaged. In various parts of the world, among marginalized community groups, community video initiatives have become instrumental in facilitating micro-level, yet significant changes in communities. Video Volunteers (VV) is an organization that promotes community media and works towards providing disadvantaged communities with journalistic, critical thinking and creative skills they need for catalysing change in their communities. Working since 2002, VV has evolved a unique community media model fostering locally-owned and managed media production, as well as building people’s capacities to articulate and share their perspectives on the issues that matter to them – on a local and a global scale. Further, by integrating a livelihood aspect within its model, VV has actively involved people from poor marginalized communities and provided them a new tool for serving their communities whilst keeping their identities intact. This paper, based on a qualitative research, seeks to map the range of VV impacts in communities and provide an in-depth analysis of factors contributing to VV impacting change in communities. Study tools included content analysis of a longitudinal sample of impact videos produced, narratives of community correspondents using the Most Significant Change Technique (MSCT) and interviews with key informants. Using a multi-fold analysis, the paper seeks to gain holistic insights. At the first level, the paper profiles the Community Correspondents (CCs), spearheading change, and maps their personal and social context and their perceptions about VV in their personal lives. Secondly, at an organizational level, the paper maps the significance of impacts brought about in the CCs communities and their association, challenges and achievements while working with VV. Lastly, at the community level, it consists of analysis of the nature of impacts achieved and aspects influencing the same. Finally, the study critiques the functioning of Video Volunteers as a community media initiative using the tipping point theory emphasizing on the power of context that is constituted by their socio-cultural environment. It concludes how empowerment of its Community Correspondents, multifarious activities during pre and post video production, and other innovative mechanisms have enabled in center staging issues of marginalized communities and snowballing processes of change in communities.

Keywords: community media, empowerment, participatory communication, social change

Procedia PDF Downloads 122
259 Review of Carbon Materials: Application in Alternative Energy Sources and Catalysis

Authors: Marita Pigłowska, Beata Kurc, Maciej Galiński

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The application of carbon materials in the branches of the electrochemical industry shows an increasing tendency each year due to the many interesting properties they possess. These are, among others, a well-developed specific surface, porosity, high sorption capacity, good adsorption properties, low bulk density, electrical conductivity and chemical resistance. All these properties allow for their effective use, among others in supercapacitors, which can store electric charges of the order of 100 F due to carbon electrodes constituting the capacitor plates. Coals (including expanded graphite, carbon black, graphite carbon fibers, activated carbon) are commonly used in electrochemical methods of removing oil derivatives from water after tanker disasters, e.g. phenols and their derivatives by their electrochemical anodic oxidation. Phenol can occupy practically the entire surface of carbon material and leave the water clean of hydrophobic impurities. Regeneration of such electrodes is also not complicated, it is carried out by electrochemical methods consisting in unblocking the pores and reducing resistances, and thus their reactivation for subsequent adsorption processes. Graphite is commonly used as an anode material in lithium-ion cells, while due to the limited capacity it offers (372 mAh g-1), new solutions are sought that meet both capacitive, efficiency and economic criteria. Increasingly, biodegradable materials, green materials, biomass, waste (including agricultural waste) are used in order to reuse them and reduce greenhouse effects and, above all, to meet the biodegradability criterion necessary for the production of lithium-ion cells as chemical power sources. The most common of these materials are cellulose, starch, wheat, rice, and corn waste, e.g. from agricultural, paper and pharmaceutical production. Such products are subjected to appropriate treatments depending on the desired application (including chemical, thermal, electrochemical). Starch is a biodegradable polysaccharide that consists of polymeric units such as amylose and amylopectin that build an ordered (linear) and amorphous (branched) structure of the polymer. Carbon is also used as a catalyst. Elemental carbon has become available in many nano-structured forms representing the hybridization combinations found in the primary carbon allotropes, and the materials can be enriched with a large number of surface functional groups. There are many examples of catalytic applications of coal in the literature, but the development of this field has been hampered by the lack of a conceptual approach combining structure and function and a lack of understanding of material synthesis. In the context of catalytic applications, the integrity of carbon environmental management properties and parameters such as metal conductivity range and bond sequence management should be characterized. Such data, along with surface and textured information, can form the basis for the provision of network support services.

Keywords: carbon materials, catalysis, BET, capacitors, lithium ion cell

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258 Strategies to Mitigate Disasters at the Hajj Religious Festival Using GIS and Agent Based Modelling

Authors: Muteb Alotaibi, Graham Clarke, Nick Malleson

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The Hajj religious festival at Mina in Saudi Arabia has always presented the opportunity for injuries or deaths. For example, in 1990, a stampede killed 1426 pilgrims, whilst in 1997, 343 people were killed and 1500 injured due to a fire fuelled by high winds sweeping through the tent city in Mina.Many more minor incidents have occurred since then. It is predicted that 5 million pilgrims will soon perform the ritual at Mina (which is, in effect, a temporary city built each year in the desert), which might lead in the future to severe congestion and accidents unless the research is conducted on actions that contribute positively to improving the management of the crowd and facilitating the flow of pilgrims safely and securely. To help prevent further disasters, it is important to first plan better, more accessible locations for emergency services across Mina to ensure a good service for pilgrims. In this paper, we first use a Location Allocation Model (LAM) within a network GIS to examine the optimal locations for key services in the temporary city of Mina. This has been undertaken in relation to the location and movement of the pilgrims during the six day religious festival. The results of various what-if scenarios have been compared against the current location of services. A major argument is that planners should be flexible and locate facilities at different locations throughout the day and night. The use of location-allocation models in this type of comparative static mode has rarely been operationalised in the literature. Second, we model pilgrim movements and behaviours along with the most crowded parts of the network. This has been modelled using an agent-based model. This model allows planners to understand the key bottlenecks in the network and at what usage levels the paths become critically congested. Thus the paper has important implications and recommendations for future disaster planning strategies. This will enable planners to see at what stage in the movements of pilgrims problems occur in terms of potential crushes and trampling incidents. The main application of this research was only customised for pedestrians as the concentration only for pedestrians who move to Jamarat via foot. Further, the network in the middle of Mina was only dedicated for pedestrians for safety, so no Buses, trains and private cars were allowed in this area to prevent the congestion within this network. Initially, this research focus on Mina city as ‘temporary city’ and also about service provision in temporary cities, which is not highlighted in literature so far. Further, it is the first study which use the dynamic demand to optimise the services in the case of day and night time. Moreover, it is the first study which link the location allocation model for optimising services with ABM to find out whether or not the service location is located in the proper location in which it’s not affecting on crowd movement in mainstream flow where some pilgrims need to have health services.

Keywords: ABM, crowd management, hajj, temporary city

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257 i-Plastic: Surface and Water Column Microplastics From the Coastal North Eastern Atlantic (Portugal)

Authors: Beatriz Rebocho, Elisabete Valente, Carla Palma, Andreia Guilherme, Filipa Bessa, Paula Sobral

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The global accumulation of plastic in the oceans is a growing problem. Plastic is transported from its source to the oceans via rivers, which are considered the main route for plastic particles from land-based sources to the ocean. These plastics undergo physical and chemical degradation resulting in microplastics. The i-Plastic project aims to understand and predict the dispersion, accumulation and impacts of microplastics (5 mm to 1 µm) and nano plastics (below 1 µm) in marine environments from the tropical and temperate land-ocean interface to the open ocean under distinct flow and climate regimes. Seasonal monitoring of the fluxes of microplastics was carried out in (three) coastal areas in Brazil, Portugal and Spain. The present work shows the first results of in-situ seasonal monitoring and mapping of microplastics in ocean waters between Ovar and Vieira de Leiria (Portugal), in which 43 surface water samples and 43 water column samples were collected in contrasting seasons (spring and autumn). The spring and autumn surface water samples were collected with a 300 µm and 150 µm pore neuston net, respectively. In both campaigns, water column samples were collected using a conical mesh with a 150 µm pore. The experimental procedure comprises the following steps: i) sieving by a metal sieve; ii) digestion with potassium hydroxide to remove the organic matter original from the sample matrix. After a filtration step, the content is retained on a membrane and observed under a stereomicroscope, and physical and chemical characterization (type, color, size, and polymer composition) of the microparticles is performed. Results showed that 84% and 88% of the surface water and water column samples were contaminated with microplastics, respectively. Surface water samples collected during the spring campaign averaged 0.35 MP.m-3, while surface water samples collected during autumn recorded 0.39 MP.m-3. Water column samples from the spring campaign had an average of 1.46 MP.m-3, while those from the autumn recorded 2.54 MP.m-3. In the spring, all microplastics found were fibers, predominantly black and blue. In autumn, the dominant particles found in the surface waters were fibers, while in the water column, fragments were dominant. In spring, the average size of surface water particles was 888 μm, while in the water column was 1063 μm. In autumn, the average size of surface and water column microplastics was 1333 μm and 1393 μm, respectively. The main polymers identified by Attenuated Total Reflectance (ATR) and micro-ATR Fourier Transform Infrared (FTIR) spectroscopy from all samples were low-density polyethylene (LDPE), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC). The significant difference between the microplastic concentration in the water column between the two campaigns could be due to the remixing of the water masses that occurred that week due to the occurrence of a storm. This work presents preliminary results since the i-Plastic project is still in progress. These results will contribute to the understanding of the spatial and temporal dispersion and accumulation of microplastics in this marine environment.

Keywords: microplastics, Portugal, Atlantic Ocean, water column, surface water

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256 The Active Social Live of #Lovewins: Understanding the Discourse of Homosexual Love and Rights in Thailand

Authors: Tinnaphop Sinsomboonthong

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The hashtag, #LoveWins, has been widely used for celebrating the victory of the LGBTQ movement since June 2015 when the US Supreme Court enacted the rights of same-sex marriage. Nowadays, the hashtag is generally used among active social media users in many countries, including Thailand. Amidst the political conflict between advocates of the junta-backed legislation related to same-sex marriage laws, known as ‘Thailand’s Civil Partnership Draft Bills,’ and its detractors, the hashtag becomes crucial for Thailand’s 2019 national election season and shortly afterward as it was one of the most crucial parts of a political campaign to rebrand many political parties’ image, create an LGBT-friendly atmosphere and neutralize the bi-polarized politics of the law. The use of the hashtag is, therefore, not just an online entertainment but a politico-discursive tool, used by many actors for many purposes. Behind the confrontation between supporters and opposers of the law, the hashtag is used by both sides to highlight the Western-centric normativity of homosexual love, closely associated with Eurocentric modernity and heteronormativity. As an online ethnographical study, this paper aims to analyze how #LoveWins is used among Thai social media users in late 2018 to mid-2019 and how it is signified by Thai social media users during the Drafted-Bills period and the 2019 national election. A number of preliminary surveys of data on Twitter were conducted in December 2018 and, more intensely, in January 2019. Later, the data survey was officially conducted twice during February and April 2019, while the data collection was done during May-June 2019. Only public posts on Twitter that include the hashtag, #LoveWins, or any hashtags quoting ‘love’ and ‘wins’ are the main targets of this research. As a result of this, the use of the hashtag can be categorized into three levels, including banal decoration, homosexual love celebration, and colonial discourse on homosexual love. Particularly in the third type of the use of the hashtag, discourse analysis is applied to reveal that this hashtag is closely associated with the discourse of development and modernity as most of the descriptive posts demonstrate aspirations to become more ‘developed and modernized’ like many Western countries and Taiwan, the LGBT capital in Asia. Thus, calls for the ‘right to homosexual love’ and the ‘right to same-sex marriage’ in Thailand are shaped and formulated within the discursive linkage between modernity, development, and love. Also, the use of #LoveWins can be considered as a de-queering process of love as only particular types of gender identity, sexual orientation, and relationships that reflect Eurocentric modernity and heteronormativity are acceptable and advocated. Due to this, more inclusive queer loves should be supported rather than a mere essentialist-traditionalist homosexual love. Homonormativity must be deconstructed, and love must no longer be reserved for only one particular type of relationship that is standardized from/by the West. It must become more inclusive.

Keywords: #LoveWins, homosexual love, LGBT rights, same-sex marriage

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255 The Expansion of Buddhism from India to Nepal Himalaya and Beyond

Authors: Umesh Regmi

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This paper explores the expansion of Buddhism from India geographically to the Himalayan region of Nepal, Tibet, India, and Bhutan in chronological historical sequence. The Buddhism practiced in Tibet is the spread of the Mahayana-Vajrayana form appropriately designed by Indian Mahasiddhas, who were the practitioners of the highest form of tantra and meditation. Vajrayana Buddhism roots in the esoteric practices incorporating the teachings of Buddha, mantras, dharanis, rituals, and sadhana for attaining enlightenment. This form of Buddhism spread from India to Nepal after the 5th Century AD and Tibet after the 7th century AD and made a return journey to the Himalayan region of Nepal, India, and Bhutan after the 8th century. The first diffusion of this form of Buddhism from India to Nepal and Tibet is partially proven through Buddhist texts and the archaeological existence of monasteries historically and at times relied on mythological traditions. The second diffusion of Buddhism in Tibet was institutionalized through the textual translations and interpretations of Indian Buddhist masters and their Tibetan disciples and the establishment of different monasteries in various parts of Tibet, later resulting in different schools and their traditions: Nyingma, Kagyu, Sakya, Gelug, and their sub-schools. The first return journey of Buddhism from Tibet to the Himalayan region of Nepal, India, and Bhutan in the 8th century is mythologically recorded in local legends of the arrival of Padmasambhava, and the second journey in the 11th century and afterward flourished by many Indian masters who practiced continuously till date. This return journey of Tibetan Buddhism has been intensified after 1959 with the Chinese occupation of Tibet, resulting in the Tibetan Buddhist masters living in exile in major locations like Kathmandu, Dharmasala, Dehradun, Sikkim, Kalimpong, and beyond. The historic-cultural-critical methodology for the recognition of the qualities of cultural expressions analysis presents the Buddhist practices of the Himalayan region, explaining the concepts of Ri (mountain as spiritual symbols), yul-lha (village deities), dhar-lha (spiritual concept of mountain passes), dharchhog-lungdhar (prayer flags), rig-sum gonpo (small stupas), Chenresig, asura (demi gods), etc. Tibetan Buddhist history has preserved important textual and practical aspects of Vajrayana from Buddhism historically in the form of arrival, advent, and development, including rising and fall. Currently, Tibetan Buddhism has influenced a great deal in the contemporary Buddhist practices of the world. The exploratory findings conducted over seven years of field visits and research in the Himalayan regions of Nepal, India, and Bhutan have demonstrated the fact that Buddhism in the Himalayan region is a return journey from Tibet and lately been popularized globally after 1959 by major monasteries and their Buddhist masters, lamas, nuns and other professionals, who have contributed in different periods of time.

Keywords: Buddhism, expansion, Himalayan region, India, Nepal, Bhutan, return, Tibet, Vajrayana Buddhism

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254 Antimicrobial Value of Olax subscorpioidea and Bridelia ferruginea on Micro-Organism Isolates of Dental Infection

Authors: I. C. Orabueze, A. A. Amudalat, S. A. Adesegun, A. A. Usman

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Dental and associated oral diseases are increasingly affecting a considerable portion of the population and are considered some of the major causes of tooth loss, discomfort, mouth odor and loss of confidence. This study focused on the ethnobotanical survey of medicinal plants used in oral therapy and evaluation of the antimicrobial activities of methanolic extracts of two selected plants from the survey for their efficacy against dental microorganisms. The ethnobotanical survey was carried out in six herbal markets in Lagos State, Nigeria by oral interviewing and information obtained from an old family manually complied herbal medication book. Methanolic extracts of Olax subscorpioidea (stem bark) and Bridelia ferruginea (stem bark) were assayed for their antimicrobial activities against clinical oral isolates (Aspergillus fumigatus, Candida albicans, Streptococcus spp, Staphylococcus aureus, Lactobacillus acidophilus and Pseudomonas aeruginosa). In vitro microbial technique (agar well diffusion method and minimum inhibitory concentration (MIC) assay) were employed for the assay. Chlorhexidine gluconate was used as the reference drug for comparison with the extract results. And the preliminary phytochemical screening of the constituents of the plants were done. The ethnobotanical survey produced plants (28) of diverse family. Different parts of plants (seed, fruit, leaf, root, bark) were mentioned but 60% mentioned were either the stem or the bark. O. subscorpioidea showed considerable antifungal activity with zone of inhibition ranging from 2.650 – 2.000 cm against Aspergillus fumigatus but no such encouraging inhibitory activity was observed in the other assayed organisms. B. ferruginea showed antibacterial sensitivity against Streptococcus spp, Staphylococcus aureus, Lactobacillus acidophilus and Pseudomonas aeruginosa with zone of inhibitions ranging from 3.400 - 2.500, 2.250 - 1.600, 2.700 - 1.950, 2.225 – 1.525 cm respectively. The minimum inhibitory concentration of O. subscorpioidea against Aspergillus fumigatus was 51.2 mg ml-1 while that of B. ferruginea against Streptococcus spp was 0.1mg ml-1 and for Staphylococcus aureus, Lactobacillus acidophilus and Pseudomonas aeruginosa were 25.6 mg ml-1. A phytochemical analysis reveals the presence of alkaloids, saponins, cardiac glycoside, tannins, phenols and terpenoids in both plants, with steroids only in B. ferruginea. No toxicity was observed among mice given the two methanolic extracts (1000 mg Kg-1) after 21 days. The barks of both plants exhibited antimicrobial properties against periodontal diseases causing organisms assayed, thus up-holding their folkloric use in oral disorder management. Further research could be done viewing these extracts as combination therapy, checking for possible synergistic value in toothpaste and oral rinse formulations for reducing oral bacterial flora and fungi load.

Keywords: antimicrobial activities, Bridelia ferruginea, dental disinfection, methanolic extract, Olax subscorpioidea, ethnobotanical survey

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253 Impact of Stress and Protein Malnutrition on the Potential Role of Epigallocatechin-3-Gallate in Providing Protection from Nephrotoxicity and Hepatotoxicity Induced by Aluminum in Rats

Authors: Azza A. Ali, Mona G. Khalil, Hemat A. Elariny, Shereen S. El Shaer

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Background: Aluminium (Al) is very abundant metal in the earth’s crust. It is a constituent of cooking utensils, medicines, cosmetics, some foods and food additives. Salts of Al are widely used in the treatment of drinking water for purification purposes. Excessive and prolonged exposure to Al causes oxidative stress and impairment of many physiological functions. Its accumulation in liver and kidney causes hepatotoxicity and nephrotoxicity. Social isolation (SI) or Protein malnutrition (PM) also increases oxidative stress and may enhance the toxicity of Al as well as the degeneration in liver and kidney. Epigallocatechin-3-gallate (EGCG) is the most abundant catechin in green tea and has strong antioxidant as well as anti-inflammatory activities and can protect against oxidative stress-induced degenerations. Objective: To study the influence of stress or PM on Al-induced nephrotoxicity and hepatotoxicity in rats, as well as on the potential role of EGCG in providing protection. Methods: Rats received daily AlCl3 (70 mg/kg, IP) for three weeks (Al-toxicity groups) except one normal control group received saline. Al-toxicity groups were divided into four treated and four untreated groups; treated rats received EGCG (10 mg/kg, IP) together with AlCl3. One group of both treated and untreated rats served as control for each of them, and the others were subjected to either stress (mild using isolation or high using electric shock) or to PM (10% casein diet). Specimens of liver and kidney were used for assessment of levels of inflammatory mediators as TNF-α, IL6β, nuclear factor kappa B (NF-κB), oxidative stress (MDA, SOD, TAC, NO), Caspase-3 and for DNA fragmentation as well as for histopathological examinations. Biochemical changes were also measured in the serum as total lipids, cholesterol, triglycerides, glucose, proteins, bilirubin, creatinine and urea as well as the level of Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and lactate deshydrogenase (LDH). Results: Nephrotoxicity and hepatotoxicity induced by Al were enhanced in rats exposed to stress and to PM. The influence of stress was more pronounced than PM. Al-toxicity was indicated by the increase in liver and kidney MDA, NO, TNF-α, IL-6β, NF-κB, caspase-3, DNA fragmentation and in ALT, AST, ALP, LDH and total lipids, cholesterol, triglycerides, glucose, proteins, bilirubin, creatinine and urea levels, together with the decrease in total proteins, SOD, TAC. EGCG provided protection against hazards of Al as indicated by the decrease in MDA, NO, TNF-α, IL-6β, NF-κB, caspase-3 and DNA fragmentation as well as in levels of ALT, AST, ALP, LDH and total lipids, cholesterol, triglycerides, glucose, proteins, bilirubin, creatinine and urea in liver and kidney, together with the increase in total proteins, SOD, TAC and confirmed by histopathological examinations. It provided more pronounced protection in high stressful conditions than in mild one than in PM. Conclusion: Stress have a bad impact on Al-induced nephrotoxicity and hepatotoxicity more than PM. Thus it can clarify and maximize the role of EGCG in providing protection. Consequently, administration of EGCG is advised with excessive Al-exposure to avoid nephrotoxicity and hepatotoxicity especially in populations more subjected to stress or PM.

Keywords: aluminum, stress, protein malnutrition, nephrotoxicity, hepatotoxicity, epigallocatechin-3-gallate, rats

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252 Wage Differentials in Pakistan by Focusing on Wage Differentials in Public and Private Sectors, Formal and Informal Sectors, and Major Occupational Groups

Authors: Asghar Ali, Narjis Khatoon

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This study focuses on the presence of wage differentials in Pakistan and also on the determinants that originate it. Since there are a smaller number of studies that are conducted on this topic in Pakistan, the current study aims to contribute in bridging the existing gap in this particular research genre. Hence, this study not only generates the desired results specific focus but it also contributes to the overall empirical work on the Pakistan economy. The preceding works which have been done to research wage determinants and wage differentials have used numerous different theories and approaches to reach their goals. The current study, in order to analyze the determinants of wage differentials in the developing economy, deals with the study of a number of such theories and approaches that are supposed as being beneficial for the purpose. This study undertakes the explanation of wage differentials in Pakistan by focusing on wage differentials in public and private sectors, formal and informal sectors, and major occupational groups. The study uses 'Wage Theory' to examine wage differentials among male and female employees in public and private sectors on varied levels of working conditions. This study also uses 'Segmented Labor Market Theory' to determine the wage differential in both public and private sectors, formal and informal, and major occupational groups in Pakistan. So the author has used various econometric techniques in order to explain and test these theories and to find out the required results. This study has employed seven different cross-sectional Labour Force Surveys for the time period between 2006-07 to 2012-13. Gender equality is not only a policy reform agenda for developing countries but also an important goal of Millennium Development Goals. This study investigates the nexus between wage inequality and economic growth and detects co-integration between gender wage differential and economic growth using ARDL bound test. It is confirmed from the empirical results that there exists long-run relationship between economic growth and wage differential. Our study indicated that half of the total female employees from fourteen major cities of Pakistan were employed in the public sector. Out of total female employees in private sector, 66 percent are employed in the formal sector, and 33 percent are working in the informal sector. Results also indicated that both men and women were paid more in the public sector compared to the private sector counterparts. Among the total female employees, only 9 percent had received any formal training, 52% were married and average years of schooling were 11 years. Further, our findings regarding wage differential between genders indicate that wage gap is lower in public sector as compared to private sector. In proportion, gender wage ratio was found to be 0.96, 0.62 and 0.66 in public, formal private and informal private sectors respectively. This suggests that in this case, private sector female employees with the same pay structure are compensated at a lower endowments rate as then public sector workers as compared to their counter parts.

Keywords: wage differentials, formal, informal, economic growth

Procedia PDF Downloads 177
251 Application of Deep Learning Algorithms in Agriculture: Early Detection of Crop Diseases

Authors: Manaranjan Pradhan, Shailaja Grover, U. Dinesh Kumar

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Farming community in India, as well as other parts of the world, is one of the highly stressed communities due to reasons such as increasing input costs (cost of seeds, fertilizers, pesticide), droughts, reduced revenue leading to farmer suicides. Lack of integrated farm advisory system in India adds to the farmers problems. Farmers need right information during the early stages of crop’s lifecycle to prevent damage and loss in revenue. In this paper, we use deep learning techniques to develop an early warning system for detection of crop diseases using images taken by farmers using their smart phone. The research work leads to building a smart assistant using analytics and big data which could help the farmers with early diagnosis of the crop diseases and corrective actions. The classical approach for crop disease management has been to identify diseases at crop level. Recently, ImageNet Classification using the convolutional neural network (CNN) has been successfully used to identify diseases at individual plant level. Our model uses convolution filters, max pooling, dense layers and dropouts (to avoid overfitting). The models are built for binary classification (healthy or not healthy) and multi class classification (identifying which disease). Transfer learning is used to modify the weights of parameters learnt through ImageNet dataset and apply them on crop diseases, which reduces number of epochs to learn. One shot learning is used to learn from very few images, while data augmentation techniques are used to improve accuracy with images taken from farms by using techniques such as rotation, zoom, shift and blurred images. Models built using combination of these techniques are more robust for deploying in the real world. Our model is validated using tomato crop. In India, tomato is affected by 10 different diseases. Our model achieves an accuracy of more than 95% in correctly classifying the diseases. The main contribution of our research is to create a personal assistant for farmers for managing plant disease, although the model was validated using tomato crop, it can be easily extended to other crops. The advancement of technology in computing and availability of large data has made possible the success of deep learning applications in computer vision, natural language processing, image recognition, etc. With these robust models and huge smartphone penetration, feasibility of implementation of these models is high resulting in timely advise to the farmers and thus increasing the farmers' income and reducing the input costs.

Keywords: analytics in agriculture, CNN, crop disease detection, data augmentation, image recognition, one shot learning, transfer learning

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250 The Environmental Concerns in Coal Mining, and Utilization in Pakistan

Authors: S. R. H. Baqri, T. Shahina, M. T. Hasan

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Pakistan is facing acute shortage of energy and looking for indigenous resources of the energy mix to meet the short fall. After the discovery of huge coal resources in Thar Desert of Sindh province, focus has shifted to coal power generation. The government of Pakistan has planned power generation of 20000 MW on coal by the year 2025. This target will be achieved by mining and power generation in Thar coal Field and on imported coal in different parts of Pakistan. Total indigenous coal production of around 3.0 million tons is being utilized in brick kilns, cement and sugar industry. Coal-based power generation is only limited to three units of 50 MW near Hyderabad from nearby Lakhra Coal field. The purpose of this presentation is to identify and redressal of issues of coal mining and utilization with reference to environmental hazards. Thar coal resource is estimated at 175 billion tons out of a total resource estimate of 184 billion tons in Pakistan. Coal of Pakistan is of Tertiary age (Palaeocene/Eocene) and classified from lignite to sub-bituminous category. Coal characterization has established three main pollutants such as Sulphur, Carbon dioxide and Methane besides some others associated with coal and rock types. The element Sulphur occurs in organic as well as inorganic forms associated with coals as free sulphur and as pyrite, gypsum, respectively. Carbon dioxide, methane and minerals are mostly associated with fractures, joints local faults, seatearth and roof rocks. The abandoned and working coal mines give kerosene odour due to escape of methane in the atmosphere. While the frozen methane/methane ices in organic matter rich sediments have also been reported from the Makran coastal and offshore areas. The Sulphur escapes into the atmosphere during mining and utilization of coal in industry. The natural erosional processes due to rivers, streams, lakes and coastal waves erode over lying sediments allowing pollutants to escape into air and water. Power plants emissions should be controlled through application of appropriate clean coal technology and need to be regularly monitored. Therefore, the systematic and scientific studies will be required to estimate the quantity of methane, carbon dioxide and sulphur at various sites such as abandoned and working coal mines, exploratory wells for coal, oil and gas. Pressure gauges on gas pipes connecting the coal-bearing horizons will be installed on surface to know the quantity of gas. The quality and quantity of gases will be examined according to the defined intervals of times. This will help to design and recommend the methods and procedures to stop the escape of gases into atmosphere. The element of Sulphur can be removed partially by gravity and chemical methods after grinding and before industrial utilization of coal.

Keywords: atmosphere, coal production, energy, pollutants

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249 Online Monitoring and Control of Continuous Mechanosynthesis by UV-Vis Spectrophotometry

Authors: Darren A. Whitaker, Dan Palmer, Jens Wesholowski, James Flaherty, John Mack, Ahmad B. Albadarin, Gavin Walker

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Traditional mechanosynthesis has been performed by either ball milling or manual grinding. However, neither of these techniques allow the easy application of process control. The temperature may change unpredictably due to friction in the process. Hence the amount of energy transferred to the reactants is intrinsically non-uniform. Recently, it has been shown that the use of Twin-Screw extrusion (TSE) can overcome these limitations. Additionally, TSE enables a platform for continuous synthesis or manufacturing as it is an open-ended process, with feedstocks at one end and product at the other. Several materials including metal-organic frameworks (MOFs), co-crystals and small organic molecules have been produced mechanochemically using TSE. The described advantages of TSE are offset by drawbacks such as increased process complexity (a large number of process parameters) and variation in feedstock flow impacting on product quality. To handle the above-mentioned drawbacks, this study utilizes UV-Vis spectrophotometry (InSpectroX, ColVisTec) as an online tool to gain real-time information about the quality of the product. Additionally, this is combined with real-time process information in an Advanced Process Control system (PharmaMV, Perceptive Engineering) allowing full supervision and control of the TSE process. Further, by characterizing the dynamic behavior of the TSE, a model predictive controller (MPC) can be employed to ensure the process remains under control when perturbed by external disturbances. Two reactions were studied; a Knoevenagel condensation reaction of barbituric acid and vanillin and, the direct amidation of hydroquinone by ammonium acetate to form N-Acetyl-para-aminophenol (APAP) commonly known as paracetamol. Both reactions could be carried out continuously using TSE, nuclear magnetic resonance (NMR) spectroscopy was used to confirm the percentage conversion of starting materials to product. This information was used to construct partial least squares (PLS) calibration models within the PharmaMV development system, which relates the percent conversion to product to the acquired UV-Vis spectrum. Once this was complete, the model was deployed within the PharmaMV Real-Time System to carry out automated optimization experiments to maximize the percentage conversion based on a set of process parameters in a design of experiments (DoE) style methodology. With the optimum set of process parameters established, a series of PRBS process response tests (i.e. Pseudo-Random Binary Sequences) around the optimum were conducted. The resultant dataset was used to build a statistical model and associated MPC. The controller maximizes product quality whilst ensuring the process remains at the optimum even as disturbances such as raw material variability are introduced into the system. To summarize, a combination of online spectral monitoring and advanced process control was used to develop a robust system for optimization and control of two TSE based mechanosynthetic processes.

Keywords: continuous synthesis, pharmaceutical, spectroscopy, advanced process control

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248 Implementing the WHO Air Quality Guideline for PM2.5 Worldwide can Prevent Millions of Premature Deaths Per Year

Authors: Despina Giannadaki, Jos Lelieveld, Andrea Pozzer, John Evans

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Outdoor air pollution by fine particles ranks among the top ten global health risk factors that can lead to premature mortality. Epidemiological cohort studies, mainly conducted in United States and Europe, have shown that the long-term exposure to PM2.5 (particles with an aerodynamic diameter less than 2.5μm) is associated with increased mortality from cardiovascular, respiratory diseases and lung cancer. Fine particulates can cause health impacts even at very low concentrations. Previously, no concentration level has been defined below which health damage can be fully prevented. The World Health Organization ambient air quality guidelines suggest an annual mean PM2.5 concentration limit of 10μg/m3. Populations in large parts of the world, especially in East and Southeast Asia, and in the Middle East, are exposed to high levels of fine particulate pollution that by far exceeds the World Health Organization guidelines. The aim of this work is to evaluate the implementation of recent air quality standards for PM2.5 in the EU, the US and other countries worldwide and estimate what measures will be needed to substantially reduce premature mortality. We investigated premature mortality attributed to fine particulate matter (PM2.5) under adults ≥ 30yrs and children < 5yrs, applying a high-resolution global atmospheric chemistry model combined with epidemiological concentration-response functions. The latter are based on the methodology of the Global Burden of Disease for 2010, assuming a ‘safe’ annual mean PM2.5 threshold of 7.3μg/m3. We estimate the global premature mortality by PM2.5 at 3.15 million/year in 2010. China is the leading country with about 1.33 million, followed by India with 575 thousand and Pakistan with 105 thousand. For the European Union (EU) we estimate 173 thousand and the United States (US) 52 thousand in 2010. Based on sensitivity calculations we tested the gains from PM2.5 control by applying the air quality guidelines (AQG) and standards of the World Health Organization (WHO), the EU, the US and other countries. To estimate potential reductions in mortality rates we take into consideration the deaths that cannot be avoided after the implementation of PM2.5 upper limits, due to the contribution of natural sources to total PM2.5 and therefore to mortality (mainly airborne desert dust). The annual mean EU limit of 25μg/m3 would reduce global premature mortality by 18%, while within the EU the effect is negligible, indicating that the standard is largely met and that stricter limits are needed. The new US standard of 12μg/m3 would reduce premature mortality by 46% worldwide, 4% in the US and 20% in the EU. Implementing the AQG by the WHO of 10μg/m3 would reduce global premature mortality by 54%, 76% in China and 59% in India. In the EU and US, the mortality would be reduced by 36% and 14%, respectively. Hence, following the WHO guideline will prevent 1.7 million premature deaths per year. Sensitivity calculations indicate that even small changes at the lower PM2.5 standards can have major impacts on global mortality rates.

Keywords: air quality guidelines, outdoor air pollution, particulate matter, premature mortality

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247 A Geographical Information System Supported Method for Determining Urban Transformation Areas in the Scope of Disaster Risks in Kocaeli

Authors: Tayfun Salihoğlu

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Following the Law No: 6306 on Transformation of Disaster Risk Areas, urban transformation in Turkey found its legal basis. In the best practices all over the World, the urban transformation was shaped as part of comprehensive social programs through the discourses of renewing the economic, social and physical degraded parts of the city, producing spaces resistant to earthquakes and other possible disasters and creating a livable environment. In Turkish practice, a contradictory process is observed. In this study, it is aimed to develop a method for better understanding of the urban space in terms of disaster risks in order to constitute a basis for decisions in Kocaeli Urban Transformation Master Plan, which is being prepared by Kocaeli Metropolitan Municipality. The spatial unit used in the study is the 50x50 meter grids. In order to reflect the multidimensionality of urban transformation, three basic components that have spatial data in Kocaeli were identified. These components were named as 'Problems in Built-up Areas', 'Disaster Risks arising from Geological Conditions of the Ground and Problems of Buildings', and 'Inadequacy of Urban Services'. Each component was weighted and scored for each grid. In order to delimitate urban transformation zones Optimized Outlier Analysis (Local Moran I) in the ArcGIS 10.6.1 was conducted to test the type of distribution (clustered or scattered) and its significance on the grids by assuming the weighted total score of the grid as Input Features. As a result of this analysis, it was found that the weighted total scores were not significantly clustering at all grids in urban space. The grids which the input feature is clustered significantly were exported as the new database to use in further mappings. Total Score Map reflects the significant clusters in terms of weighted total scores of 'Problems in Built-up Areas', 'Disaster Risks arising from Geological Conditions of the Ground and Problems of Buildings' and 'Inadequacy of Urban Services'. Resulting grids with the highest scores are the most likely candidates for urban transformation in this citywide study. To categorize urban space in terms of urban transformation, Grouping Analysis in ArcGIS 10.6.1 was conducted to data that includes each component scores in significantly clustered grids. Due to Pseudo Statistics and Box Plots, 6 groups with the highest F stats were extracted. As a result of the mapping of the groups, it can be said that 6 groups can be interpreted in a more meaningful manner in relation to the urban space. The method presented in this study can be magnified due to the availability of more spatial data. By integrating with other data to be obtained during the planning process, this method can contribute to the continuation of research and decision-making processes of urban transformation master plans on a more consistent basis.

Keywords: urban transformation, GIS, disaster risk assessment, Kocaeli

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246 Assessment of Environmental Impact for Rice Mills in Burdwan District: Special Emphasis on Groundwater, Surface Water, Soil, Vegetation and Human Health

Authors: Rajkumar Ghosh, Bhabani Prasad Mukhopadhay

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Rice milling is an important activity in agricultural economy of India, particularly the Burdwan district. However, the environmental impact of rice mills is frequently underestimated. The environmental impact of rice mills in the Burdwan district is a major source of concern, given the importance of rice milling in the local economy and food supply. In the Burdwan district, more than fifty (50) rice mills are in operation. The goal of this study is to investigate the effects of rice mills on several environmental components, with a particular emphasis on groundwater, surface water, soil, and vegetation. The research comprises a thorough review of numerous rice mills located around the district, utilising both qualitative and quantitative approaches. Water samples taken from wells near rice mills will be tested for groundwater quality, with an emphasis on factors such as heavy metal pollution and pollutant concentrations. Monitoring rice mill discharge into neighbouring bodies of water and studying the potential impact on aquatic ecosystems will be part of surface water evaluations. Furthermore, soil samples from the surrounding areas will be taken to examine changes in soil characteristics, nutrient content, and potential contamination from milling waste disposal. Vegetation studies will be conducted to investigate the effects of emissions and effluents on plant health and biodiversity in the region. The findings will provide light on the extent of environmental degradation caused by rice mills in the Burdwan district, as well as valuable insight into the effects of such operations on water, soil, and vegetation. The findings will aid in the development of appropriate legislation and regulations to reduce negative environmental repercussions and promote sustainable practises in the rice milling business. In some cases, heavy metals have been related to health problems. Heavy metals (As, Cd, Cu, Pb, Cr, Hg) are linked to skin, lung, brain, kidney, liver, metabolic, spleen, cardiovascular, haematological, immunological, gastrointestinal, testes, pancreatic, metabolic, and bone problems. As a result, this study contributes to a better knowledge of industrial environmental impacts and establishes the framework for future studies aimed at developing a more ecologically balanced and resilient Burdwan district. The following recommendations are offered for reducing the rice mill's environmental impact: To keep untreated effluents out of bodies of water, adequate waste management systems must be established. Use environmentally friendly rice milling processes to reduce pollution. To avoid soil pollution, rice mill by-products should be used as fertiliser in a controlled and appropriate manner. Groundwater, surface water, soil, and vegetation are all regularly monitored in order to study and adapt to environmental changes. By adhering to these principles, the rice milling industry of Burdwan district may achieve long-term growth while lowering its environmental effect and safeguarding the environment for future generations.

Keywords: groundwater, environmental analysis, biodiversity, rice mill, waste management, diseases, industrial impact

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245 Analyzing the Effects of Bio-fibers on the Stiffness and Strength of Adhesively Bonded Thermoplastic Bio-fiber Reinforced Composites by a Mixed Experimental-Numerical Approach

Authors: Sofie Verstraete, Stijn Debruyne, Frederik Desplentere

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Considering environmental issues, the interest to apply sustainable materials in industry increases. Specifically for composites, there is an emerging need for suitable materials and bonding techniques. As an alternative to traditional composites, short bio-fiber (cellulose-based flax) reinforced Polylactic Acid (PLA) is gaining popularity. However, these thermoplastic based composites show issues in adhesive bonding. This research focusses on analyzing the effects of the fibers near the bonding interphase. The research applies injection molded plate structures. A first important parameter concerns the fiber volume fraction, which directly affects adhesion characteristics of the surface. This parameter is varied between 0 (pure PLA) and 30%. Next to fiber volume fraction, the orientation of fibers near the bonding surface governs the adhesion characteristics of the injection molded parts. This parameter is not directly controlled in this work, but its effects are analyzed. Surface roughness also greatly determines surface wettability, thus adhesion. Therefore, this research work considers three different roughness conditions. Different mechanical treatments yield values up to 0.5 mm. In this preliminary research, only one adhesive type is considered. This is a two-part epoxy which is cured at 23 °C for 48 hours. In order to assure a dedicated parametric study, simple and reproduceable adhesive bonds are manufactured. Both single lap (substrate width 25 mm, thickness 3 mm, overlap length 10 mm) and double lap tests are considered since these are well documented and quite straightforward to conduct. These tests are conducted for the different substrate and surface conditions. Dog bone tensile testing is applied to retrieve the stiffness and strength characteristics of the substrates (with different fiber volume fractions). Numerical modelling (non-linear FEA) relates the effects of the considered parameters on the stiffness and strength of the different joints, obtained through the abovementioned tests. Ongoing work deals with developing dedicated numerical models, incorporating the different considered adhesion parameters. Although this work is the start of an extensive research project on the bonding characteristics of thermoplastic bio-fiber reinforced composites, some interesting results are already prominent. Firstly, a clear correlation between the surface roughness and the wettability of the substrates is observed. Given the adhesive type (and viscosity), it is noticed that an increase in surface energy is proportional to the surface roughness, to some extent. This becomes more pronounced when fiber volume fraction increases. Secondly, ultimate bond strength (single lap) also increases with increasing fiber volume fraction. On a macroscopic level, this confirms the positive effect of fibers near the adhesive bond line.

Keywords: adhesive bonding, bio-fiber reinforced composite, flax fibers, lap joint

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244 Determining Factors of Suspended Glass Systems with Pre-Stress Cable Truss

Authors: Cemil Atakara, Hüseyin Eryaman

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The use of glass as an envelope of a building has been increasing in the twentieth century. For more transparency and dematerialization new glass facade types have emerged in the past two decades which depends on point fixed glazing system (PFGS). The aim of this study is to analyze of the PFGS systems which are used on the glass curtain wall according to their types, degree, architectural and structural effects. This new system is desired because it enhances the transparency of the façade and it minimizes the component of the frames or of the profiles. This PFGS led to new structural elements which use cables, rods, trusses when designing a glass building facades, this structural element called the suspended glass system with pre-stressed cable truss (SGSPCT) which has been used for the first time in 1980 in Serres building. The twenty glass buildings which are designed in different systems have been analyzed during this study. After these analyses five selected SGSPCT building analyzed deeply and one skeletal frame building selected from Lefkosa redesigned according to the analysis results. These selected buildings have been included of various cable-truss system typologies and degree. The methodology of this study is building analysis method and literature survey with the help of books, articles, magazines, drawings, internet sources and applied connection details of the glass buildings. The selected five glass buildings and case building have been detailed analyzed with their architectural drawings, photographs and details. A gridshell structure can be compared with a shell structure; it consists of discrete members connecting nodal points. As these nodal points lie on the surface of an imaginary shell, their shapes function almost identically. Difference between shell and gridshell structures can be found in the fact that, due to their free-form and thus, due to the presence of bending forces, gridshells are required to resist loading through their cross-section. This research is divided into parts. A general study about the glass building and cable-glass and grid shell system will be done in the first chapters. Structural analyses and detailed analyses with schematic drawings with the plans, sections of the selected buildings will be explained in the second part. The third part it consists of the advantages and disadvantages of the use of the SGSPCT and Grid Shell in architecture. The study consists of four chapters including the introduction chapter. The general information of the SGSPCT and glazing system has been mentioned in the first chapter. Structural features, typologies, transparency principle and analytical information on systems have been explained of the selected buildings in the second chapter. The detailed analyses of case building have been done according to their schematic drawings with the plans, sections in the third chapter. After third chapter SGSPCT discussed on to the case building and selected buildings. SGSPCT systems have been compared with their advantages and disadvantages to the other systems. Advantages of cable-truss systems and SGSPCT have been concluded that the use of glass substrates in the last chapter.

Keywords: cable truss, glass, grid shell, transparency

Procedia PDF Downloads 395