Search results for: Christian Kind
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1702

Search results for: Christian Kind

802 Gait Analysis in Total Knee Arthroplasty

Authors: Neeraj Vij, Christian Leber, Kenneth Schmidt

Abstract:

Introduction: Total knee arthroplasty is a common procedure. It is well known that the biomechanics of the knee do not fully return to their normal state. Motion analysis has been used to study the biomechanics of the knee after total knee arthroplasty. The purpose of this scoping review is to summarize the current use of gait analysis in total knee arthroplasty and to identify the preoperative motion analysis parameters for which a systematic review aimed at determining the reliability and validity may be warranted. Materials and Methods: This IRB-exempt scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist strictly. Five search engines were searched for a total of 279 articles. Articles underwent a title and abstract screening process followed by full-text screening. Included articles were placed in the following sections: the role of gait analysis as a research tool for operative decisions, other research applications for motion analysis in total knee arthroplasty, gait analysis as a tool in predicting radiologic outcomes, gait analysis as a tool in predicting clinical outcomes. Results: Eleven articles studied gait analysis as a research tool in studying operative decisions. Motion analysis is currently used to study surgical approaches, surgical techniques, and implant choice. Five articles studied other research applications for motion analysis in total knee arthroplasty. Other research applications for motion analysis currently include studying the role of the unicompartmental knee arthroplasty and novel physical therapy protocols aimed at optimizing post-operative care. Two articles studied motion analysis as a tool for predicting radiographic outcomes. Preoperative gait analysis has identified parameters than can predict postoperative tibial component migration. 15 articles studied motion analysis in conjunction with clinical scores. Conclusions: There is a broad range of applications within the research domain of total knee arthroplasty. The potential application is likely larger. However, the current literature is limited by vague definitions of ‘gait analysis’ or ‘motion analysis’ and a limited number of articles with preoperative and postoperative functional and clinical measures. Knee adduction moment, knee adduction impulse, total knee range of motion, varus angle, cadence, stride length, and velocity have the potential for integration into composite clinical scores. A systematic review aimed at determining the validity, reliability, sensitivities, and specificities of these variables is warranted.

Keywords: motion analysis, joint replacement, patient-reported outcomes, knee surgery

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801 Investigation of Fluid-Structure-Seabed Interaction of Gravity Anchor under Liquefaction and Scour

Authors: Vinay Kumar Vanjakula, Frank Adam, Nils Goseberg, Christian Windt

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When a structure is installed on a seabed, the presence of the structure will influence the flow field around it. The changes in the flow field include, formation of vortices, turbulence generation, waves or currents flow breaking and pressure differentials around the seabed sediment. These changes allow the local seabed sediment to be carried off and results in Scour (erosion). These are a threat to the structure's stability. In recent decades, rapid developments of research work and the knowledge of scour On fixed structures (bridges and Monopiles) in rivers and oceans has been carried out, and very limited research work on scour and liquefaction for gravity anchors, particularly for floating Tension Leg Platform (TLP) substructures. Due to its importance and need for enhancement of knowledge in scour and liquefaction around marine structures, the MarTERA funded a three-year (2020-2023) research program called NuLIMAS (Numerical Modeling of Liquefaction Around Marine Structures). It’s a group consists of European institutions (Universities, laboratories, and consulting companies). The objective of this study is to build a numerical model that replicates the reality, which indeed helps to simulate (predict) underwater flow conditions and to study different marine scour and Liquefication situations. It helps to design a heavyweight anchor for the TLP substructure and to minimize the time and expenditure on experiments. And also, the achieved results and the numerical model will be a basis for the development of other design and concepts For marine structures. The Computational Fluid Dynamics (CFD) numerical model will build in OpenFOAM. A conceptual design of heavyweight anchor for TLP substructure is designed through taking considerations of available state-of-the-art knowledge on scour and Liquefication concepts and references to Previous existing designs. These conceptual designs are validated with the available similar experimental benchmark data and also with the CFD numerical benchmark standards (CFD quality assurance study). CFD optimization model/tool is designed as to minimize the effect of fluid flow, scour, and Liquefication. A parameterized model is also developed to automate the calculation process to reduce user interactions. The parameters such as anchor Lowering Process, flow optimized outer contours, seabed interaction study, and FSSI (Fluid-Structure-Seabed Interactions) are investigated and used to carve the model as to build an optimized anchor.

Keywords: gravity anchor, liquefaction, scour, computational fluid dynamics

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800 Renewable Energy Industry Trends and Its Contributions to the Development of Energy Resilience in an Era of Accelerating Climate Change

Authors: A. T. Asutosh, J. Woo, M. Kouhirostami, M. Sam, A. Khantawang, C. Cuales, W. Ryor, C. Kibert

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Climate change and global warming vortex have grown to alarming proportions. Therefore, the need for a shift in the conceptualization of energy production is paramount. Energy practices have been created in the current situation. Fossil fuels continue their prominence, at the expense of renewable sources. Despite this abundance, a large percentage of the world population still has no access to electricity but there have been encouraging signs in global movement from nonrenewable to renewable energy but means to reverse climate change have been elusive. Worldwide, organizations have put tremendous effort into innovation. Conferences and exhibitions act as a platform that allows a broad exchange of information regarding trends in the renewable energy field. The Solar Power International (SPI) conference and exhibition is a gathering of concerned activists, and probably the largest convention of its kind. This study investigates current development in the renewable energy field, analyzing means by which industry is being applied to the issue. In reviewing the 2019 SPI conference, it was found innovations in recycling and assessing the environmental impacts of the solar products that need critical attention. There is a huge movement in the electrical storage but there exists a large gap in the development of security systems. This research will focus on solar energy, but impacts will be relevant to the entire renewable energy market.

Keywords: climate change, renewable energy, solar, trends, research, solar power international, SPI

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799 The Influence of Silica on the Properties of Cementitious Composites

Authors: Eva Stefanovska, Estefania Cuenca, Aleksandra Momirov, Monika Fidanchevska, Liberato Ferrara, Emilija Fidanchevski

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Silica is used in construction materials as a part of natural raw materials or as an additive in powder form (micro and nano dimensions). SiO₂ particles in cement act as centers of nucleation, as a filler or as pozzolan material. In this regard, silica improves the microstructure of cementitious composites, increases the mechanical properties, and finally also results into improved durability of the final products. Improved properties of cementitious composites may lead to better structural efficiency, which, together with increased durability, results into increased sustainability signature of structures made with this kind of materials. The aim of the present work was to investigate the influence of silica on the properties of cement. Fly ash (as received and mechanically activated) and synthetized silica (sol-gel method using TEOS as precursor) was used in the investigation as source of silica. Four types of cement mixtures were investigated (reference cement paste, cement paste with addition of 15wt.% as-received fly ash, cement paste with 15 wt.% mechanically activated fly ash and cement paste with 14wt.% mechanically activated fly ash and 1 wt.% silica). The influence of silica on setting time and mechanical properties (2, 7 and 28 days) was followed. As a matter of fact it will be shown that cement paste with composition 85 wt. % cement, 14 wt.% mechanically activated fly ash and 1 wt. % SiO₂ obtained by the sol-gel method was the best performing one, with increased compressive and flexure strength by 9 and 10 % respectively, as compared to the reference mixture. Acknowledgements: 'COST Action CA15202, www.sarcos.eng.cam.ac.uk'

Keywords: cement, fly ash, mechanical properties, silica, sol-gel

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798 EWMA and MEWMA Control Charts for Monitoring Mean and Variance in Industrial Processes

Authors: L. A. Toro, N. Prieto, J. J. Vargas

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There are many control charts for monitoring mean and variance. Among these, the X y R, X y S, S2 Hotteling and Shewhart control charts, for mentioning some, are widely used for monitoring mean a variance in industrial processes. In particular, the Shewhart charts are based on the information about the process contained in the current observation only and ignore any information given by the entire sequence of points. Moreover, that the Shewhart chart is a control chart without memory. Consequently, Shewhart control charts are found to be less sensitive in detecting smaller shifts, particularly smaller than 1.5 times of the standard deviation. These kind of small shifts are important in many industrial applications. In this study and effective alternative to Shewhart control chart was implemented. In case of univariate process an Exponentially Moving Average (EWMA) control chart was developed and Multivariate Exponentially Moving Average (MEWMA) control chart in case of multivariate process. Both of these charts were based on memory and perform better that Shewhart chart while detecting smaller shifts. In these charts, information the past sample is cumulated up the current sample and then the decision about the process control is taken. The mentioned characteristic of EWMA and MEWMA charts, are of the paramount importance when it is necessary to control industrial process, because it is possible to correct or predict problems in the processes before they come to a dangerous limit.

Keywords: control charts, multivariate exponentially moving average (MEWMA), exponentially moving average (EWMA), industrial control process

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797 Failure Load Investigations in Adhesively Bonded Single-Strap Joints of Dissimilar Materials Using Cohesive Zone Model

Authors: B. Paygozar, S.A. Dizaji

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Adhesive bonding is a highly valued type of fastening mechanical parts in complex structures, where joining some simple components is always needed. This method is of several merits, such as uniform stress distribution, appropriate bonding strength, and fatigue performance, and lightness, thereby outweighing other sorts of bonding methods. This study is to investigate the failure load of adhesive single-strap joints, including adherends of different sizes and materials. This kind of adhesive joint is very practical in different industries, especially when repairing the existing joints or attaching substrates of dissimilar materials. In this research, experimentally validated numerical analyses carried out in a commercial finite element package, ABAQUS, are utilized to extract the failure loads of the joints, based on the cohesive zone model. In addition, the stress analyses of the substrates are performed in order to acquire the effects of lowering the thickness of the substrates on the stress distribution inside them to avoid designs suffering from the necking or failure of the adherends. It was found out that this method of bonding is really feasible in joining dissimilar materials which can be utilized in a variety of applications. Moreover, the stress analyses indicated the minimum thickness for the adherends so as to avoid the failure of them.

Keywords: cohesive zone model, dissimilar materials, failure load, single strap joint

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796 Socioeconomic Values of Fertility in Islam

Authors: Mohamed Hamed Mohamed Ahmed Alameer

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Population studies, essentially deals with the size, growth, and distribution of the population in a given area. Size, growth, and distribution are determined by three major factors, which are fertility mortality, and migration. Of these factors, fertility- as a number of live births a woman has actually had- is a potent socio-demographic force in vital process of population growth. So, fertility is a major component of population growth. It is one of the main determinants of population growth and has crucial role in population dynamic, because it measures the rate at which a population increased. In fact the levels of fertility are vary widely among nations, countries, geographic regions, ethnic, socio- economic groups, and religious groups. Fertility differential by religion have been empirically documented in a large numbers of countries. For instance, many researchers in developing and developed countries investigated the differential of fertility among Muslims and Non- Muslims. Most of them have found that fertility of Muslims is higher than fertility of non Muslims. And Muslims have a tendency for large families comparing to non- Muslims population. On the basis of this; Islam by it itself could play an important role in shaping attitudes and values of fertility, such as: sustainability of human kind, developmental reasons, religious Motivations, socioeconomic Motivations, and Psychological Motivation. Therefore, this paper investigates socio-economic values of fertility in Islam and compare it to Malthusian and neo Malthusian functionalists and conflict perspectives.

Keywords: islam, fertility, socioeconomic values, social sciences

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795 Traveling Abroad and the Construction of British Identity and Culture in Selected Women Writers: Lady Elizabeth Craven's A Journey Through the Crimea to Constantinople (1789) and Lady Mary Wortley Montagu's Embassy Letters (1716-1718)

Authors: Raja Al-Khalili

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Traveling abroad for British citizens in the eighteenth century was usually performed for two reasons. The first major form was for administering the expanding realm of the British Empire and its need for officials in governing the natives and facilitating the work of business companies. The other form of travel was for pleasure and involved a manifestation of wealth. This form of travel was a prelude for the modern industry of tourism and usually involved a tour of Europe and the Mediterranean. In both forms of travel the British encountered a myriad of cultures. Travel had fostered a sense of pride and confirmed an ethnocentric view of British superiority, but it also brought a critical self-examination of belonging to a colonial empire that thrives on the weaknesses of other nations. Women writers in particular have sought in the travels a kind of self-exploration of the nature of social patriarchy in a diversity of cultures. Both Lady Elizabeth Craven in A Journey through the Crimea to Constantinople (1789) and Lady Mary Wortley Montagu in Embassy Letters (1716-1718) have observed the culture of the Ottomans and then pursued to reflect on the social role of women in England.

Keywords: travel writing, Elizabeth Craven, Lady Mary Wortley, patriarchy

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794 The Role of Extrovert and Introvert Personality in Second Language Acquisition

Authors: Fatma Hsain Ali Suliman

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Personality plays an important role in acquiring a second language. For second language learners to make maximum progress with their own learning styles, their individual differences must be recognized and attended to. Personality is considered to be a pattern of unique characteristics that give a person’s behavior a kind of consistency and individuality. Therefore, the enclosed study, which is entitled “The Role of Personality in Second language Acquisition: Extroversion and Introversion”, tends to shed light on the relationship between learners’ personalities and second language acquisition process. In other words, it aims at drawing attention to how individual differences of students as being extroverts or introverts could affect the language acquisition process. As a literature review, this paper discusses the results of some studies concerning this issue as well as the point views of researchers and scholars who have focused on the effect of extrovert and introvert personality on acquiring a second language. To accomplish the goals of this study, which is divided into 5 chapters including introduction, review of related literature, research method and design, results and discussions and conclusions and recommendations, 20 students of English Department, Faculty of Arts, Misurata University, Libya were handed out a questionnaire to figure out the effect of their personalities on the learning process. Finally, to be more sure about the role of personality in a second language acquisition process, the same students who were given the questionnaire were observed in their ESL classes.

Keywords: second language acquisition, personality, extroversion, introversion, individual differences, language learning strategy, personality factors, psycho linguistics

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793 Making New Theoretical Insights into Violence: The Temporal and Spatial Relevance of Blood Spatter Crime Scene Investigations

Authors: Simone Jane Dennis

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This paper leverages the spatial and temporal investigative strategy utilized by crime scene investigators – blood spatter work– to engage with the real and metaphorical memorialization of blood-soaked places. It uses this key trope with phenomenological sensibility, to trace the physical and temporal movement of blood outbound from the human body to sites beyond. Working backward, as crime scene investigators do, this paper traces the importance of both space and time and their confluence, to developing a comprehensive theory of violence. To do this work, the paper engages a range of geo-violent scales, from murder scenes to genocides, to both engage an extraordinarily replete literature of bloodshed across history and to move beyond analyses of how significance is assigned to the sites in which blood comes to rest to instead consider the importance of space and time to the structure of violence itself. It is in this regard that the kind of investigative work upon which blood spatter analysis depends is crucial: it engages time and space in reverse to understand the microscopic relations between bodies, places, and numerous (biological, clock, and seasonal) temporalities. Considering the circumstances under which blood escaped a body, the details of its destination in place, and the temporal circumstances of corporal departure, is crucial to making new knowledge about the peculiar temporality and spatiality of violence itself.

Keywords: blood, crime scenes, temporality, violence

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792 Principles for the Realistic Determination of the in-situ Concrete Compressive Strength under Consideration of Rearrangement Effects

Authors: Rabea Sefrin, Christian Glock, Juergen Schnell

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The preservation of existing structures is of great economic interest because it contributes to higher sustainability and resource conservation. In the case of existing buildings, in addition to repair and maintenance, modernization or reconstruction works often take place in the course of adjustments or changes in use. Since the structural framework and the associated load level are usually changed in the course of the structural measures, the stability of the structure must be verified in accordance with the currently valid regulations. The concrete compressive strength of the existing structures concrete and the derived mechanical parameters are of central importance for the recalculation and verification. However, the compressive strength of the existing concrete is usually set comparatively low and thus underestimated. The reasons for this are too small numbers, and large scatter of material properties of the drill cores, which are used for the experimental determination of the design value of the compressive strength. Within a structural component, the load is usually transferred over the area with higher stiffness and consequently with higher compressive strength. Therefore, existing strength variations within a component only play a subordinate role due to rearrangement effects. This paper deals with the experimental and numerical determination of such rearrangement effects in order to calculate the concrete compressive strength of existing structures more realistic and economical. The influence of individual parameters such as the specimen geometry (prism or cylinder) or the coefficient of variation of the concrete compressive strength is analyzed in experimental small-part tests. The coefficients of variation commonly used in practice are adjusted by dividing the test specimens into several layers consisting of different concretes, which are monolithically connected to each other. From each combination, a sufficient number of the test specimen is produced and tested to enable evaluation on a statistical basis. Based on the experimental tests, FE simulations are carried out to validate the test results. In the frame of a subsequent parameter study, a large number of combinations is considered, which had not been investigated in the experimental tests yet. Thus, the influence of individual parameters on the size and characteristic of the rearrangement effect is determined and described more detailed. Based on the parameter study and the experimental results, a calculation model for a more realistic determination of the in situ concrete compressive strength is developed and presented. By considering rearrangement effects in concrete during recalculation, a higher number of existing structures can be maintained without structural measures. The preservation of existing structures is not only decisive from an economic, sustainable, and resource-saving point of view but also represents an added value for cultural and social aspects.

Keywords: existing structures, in-situ concrete compressive strength, rearrangement effects, recalculation

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791 A Study of Level of Happiness in Orphans of Patna District

Authors: Riya Kartikee, Uday Shankar

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Background –.Happiness refers to a range of the balance of positive and pleasant emotions of joy, pride, contentment, gratitude, and living with ethics. Happiness is an experience combined with a sense that one’s life is good, meaningful, and worth a while, but in the context of orphans who have lost their birthgivers, their parents who play an important role in bringing necessities and comfort to them, but many terms of the above phases are missing in the life of orphan So, stress increases because of lack of love, attention, sympathy, care, they experience many kind of trauma and also in some cases their lives get worst as they face some physiological abuse, sexual abuse, they are forced to have stress at a not only mentally but physically also in the context of Patna, Bihar where many people are below poverty line, lack of resources is a normal condition for the Orphanages.AIM- The present study was intended to study the level of Happiness among the orphans of Patna District, also it was attempted to find the role of happiness in their lives as an individual.Method- The sample of 70 Orphans in the age group of 12 to 18 years were taken from the orphanages of Patna district-Apnaghar, Rainbow homes, etc. Purposive sampling was used in the study, There has been one research tool used in the study, which is Happiness scale by Dr.R.L Bhardwaj and Dr.Poonam R Das. Results- Results have revealed that Orphans have possessed a very low level of happiness and unhappiness was related due to their living conditions in the orphanage.Conclusion-It can be stated that the Level of happiness is an important missing determinant in the lives of orphans.

Keywords: happiness, orphans, patna, orphanage

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790 Investigations on the Influence of Optimized Charge Air Cooling for a Diesel Passenger Car

Authors: Christian Doppler, Gernot Hirschl, Gerhard Zsiga

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Starting from 2020, an EU-wide CO2-limitation of 95g/km is scheduled for the average of an OEMs passenger car fleet. Considering that, further measures of optimization on the diesel cycle will be necessary in order to reduce fuel consumption and emissions while keeping performance values adequate at the least. The present article deals with charge air cooling (CAC) on the basis of a diesel passenger car model in a 0D/1D-working process calculation environment. The considered engine is a 2.4 litre EURO VI diesel engine with variable geometry turbocharger (VGT) and low-pressure exhaust gas recirculation (LP EGR). The object of study was the impact of charge air cooling on the engine working process at constant boundary conditions which could have been conducted with an available and validated engine model in AVL BOOST. Part load was realized with constant power and NOx-emissions, whereas full load was accomplished with a lambda control in order to obtain maximum engine performance. The informative results were used to implement a simulation model in Matlab/Simulink which is further integrated into a full vehicle simulation environment via coupling with ICOS (Independent Co-Simulation Platform). Next, the dynamic engine behavior was validated and modified with load steps taken from the engine test bed. Due to the modular setup in the Co-Simulation, different CAC-models have been simulated quickly with their different influences on the working process. In doing so, a new cooler variation isn’t needed to be reproduced and implemented into the primary simulation model environment, but is implemented quickly and easily as an independent component into the simulation entity. By means of the association of the engine model, longitudinal dynamics vehicle model and different CAC models (air/air & water/air variants) in both steady state and transient operational modes, statements are gained regarding fuel consumption, NOx-emissions and power behavior. The fact that there is no more need of a complex engine model is very advantageous for the overall simulation volume. Beside of the simulation with the mentioned demonstrator engine, there have also been conducted several experimental investigations on the engine test bench. Here the comparison of a standard CAC with an intake-manifold-integrated CAC was executed in particular. Simulative as well as experimental tests showed benefits for the water/air CAC variant (on test bed especially the intake manifold integrated variant). The benefits are illustrated by a reduced pressure loss and a gain in air efficiency and CAC efficiency, those who all lead to minimized emission and fuel consumption for stationary and transient operation.

Keywords: air/water-charge air cooler, co-simulation, diesel working process, EURO VI fuel consumption

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789 Monitoring of Sustainability of Extruded Soya Product TRADKON SPC-TEX in Order to Define Expiration Date

Authors: Radovan Čobanović, Milica Rankov Šicar

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New attitudes about nutrition impose new styles, and therefore a neNew attitudes about nutrition impose new styles, and therefore a new kind of food. The goal of our work was to define the shelf life of new extruded soya product with minimum 65% of protein based on the analyses. According to the plan it was defined that a certain quantity of the same batch of new product (soybean flakes) which had predicted shelf life of 2 years had to be stored for 24 months in storage and analyzed at the beginning and end of sustainability plan on instrumental analyses (heavy metals, pesticides and mycotoxins) and every month on sensory analyses (odor, taste, color, consistency), microbiological analyses (Salmonella spp., Escherichia coli, Enterobacteriaceae, sulfite-reducing clostridia, Listeria monocytogenes), chemical analyses (protein, ash, fat, crude cellulose, granulation) and at the beginning on GMO analyses. All analyses were tested according to: sensory analyses ISO 6658, Salmonella spp ISO 6579, Escherichia coli ISO 16649-2, Enterobacteriaceae ISO 21528-2, sulfite-reducing clostridia ISO 15213 and Listeria monocytogenes ISO 11290-2, chemical and instrumental analyses Serbian ordinance on the methods of physico-chemical analyses and GMO analyses JRC Compendium. The results obtained after the analyses which were done according to the plan during the 24 months indicate that are no changes of products concerning both sensory and chemical analyses. As far as microbiological results are concerned Salmonella spp was not detected and all other quantitative analyses showed values <10 cfu/g. The other parameters for food safety (heavy metals, pesticides and mycotoxins) were not present in analyzed samples and also all analyzed samples were negative concerning genetic testing. On the basis of monitoring the sample under defined storage conditions and analyses of quality control, GMO analyses and food safety of the sample during the shelf within two years, the results showed that all the parameters of the sample during defined period is in accordance with Serbian regulative so that indicate that predicted shelf life can be adopted.w kind of food. The goal of our work was to define the shelf life of new extruded soya product with minimum 65% of protein based on the analyses. According to the plan it was defined that a certain quantity of the same batch of new product (soybean flakes) which had predicted shelf life of 2 years had to be stored for 24 months in storage and analyzed at the beginning and end of sustainability plan on instrumental analyses (heavy metals, pesticides and mycotoxins) and every month on sensory analyses (odor, taste, color, consistency), microbiological analyses (Salmonella spp., Escherichia coli, Enterobacteriaceae, sulfite-reducin clostridia, Listeria monocytogenes), chemical analyses (protein, ash, fat, crude cellulose, granulation) and at the beginning on GMO analyses. All analyses were tested according: sensory analyses ISO 6658, Salmonella spp ISO 6579, Escherichia coli ISO 16649-2, Enterobacteriaceae ISO 21528-2, sulfite-reducing clostridia ISO 15213 and Listeria monocytogenes ISO 11290-2, chemical and instrumental analyses Serbian ordinance on the methods of physico-chemical analyses and GMO analyses JRC Compendium. The results obtained after the analyses which were done according to the plan during the 24 months indicate that are no changes of products concerning both sensory and chemical analyses. As far as microbiological results are concerned Salmonella spp was not detected and all other quantitative analyses showed values <10 cfu/g. The other parameters for food safety (heavy metals, pesticides and mycotoxins) were not present in analyzed samples and also all analyzed samples were negative concerning genetic testing. On the basis of monitoring the sample under defined storage conditions and analyses of quality control, GMO analyses and food safety of the sample during the shelf within two years, the results showed that all the parameters of the sample during defined period is in accordance with Serbian regulative so that indicate that predicted shelf life can be adopted.

Keywords: extruded soya product, food safety analyses, GMO analyses, shelf life

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788 Synthesis of Magnesium Oxide in Spinning Disk Reactor and Its Applications in Cycloaddition of Carbon Dioxide to Epoxides

Authors: Tzu-Wen Liu, Yi-Feng Lin, Yu-Shao Chen

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CO_2 is believed to be partly responsible for changes to the global climates. Carbon capture and storage (CCS) is one way to reduce carbon dioxide emissions in the past. Recently, how to convert the captured CO_2 into fine chemicals gets lots of attention owing to reducing carbon dioxide emissions and providing greener feedstock for the chemicals industry. A variety of products can be manufactured from carbon dioxide and the most attractive products are cyclic carbonates. Therefore, the kind of catalyst plays an important role in cycloaddition of carbon dioxide to epoxides. Magnesium oxide can be an efficiency heterogeneous catalyst for the cycloaddition of carbon dioxide to epoxides because magnesium oxide has both acid and base active sites and can provide the adsorption of carbon dioxide, promoting ring-opening reaction. Spinning disk reactor (SDR) is one of the device of high-gravity technique and has successfully used for synthesis of nanoparticles by precipitation methods because of the high mass transfer rate. Synthesis of nanoparticles in SDR has advantages of low energy consumption and easy to scale up. The aim of this research is to synthesize magnesium hydroxide nanoparticles in SDR as precursors for magnesium oxide. Experimental results showed that the calcination temperature of magnesium hydroxide to magnesium oxide, and the pressure and temperature of cycloaddition reaction had significantly effect on the conversion and selectivity of the reaction.

Keywords: magnesium oxide, catalyst, cycloaddition, spinning disk reactor, carbon dioxide

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787 Urban Networks as Model of Sustainable Design

Authors: Agryzkov Taras, Oliver Jose L., Tortosa Leandro, Vicent Jose

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This paper aims to demonstrate how the consideration of cities as a special kind of complex network, called urban network, may lead to the use of design tools coming from network theories which, in fact, results in a quite sustainable approach. There is no doubt that the irruption in contemporary thought of Gaia as an essential political agent proposes a narrative that has been extended to the field of creative processes in which, of course, the activity of Urban Design is found. The rationalist paradigm is put in crisis, and from the so-called sciences of complexity, its way of describing reality and of intervening in it is questioned. Thus, a new way of understanding reality surges, which has to do with a redefinition of the human being's own place in what is now understood as a delicate and complex network. In this sense, we know that in these systems of connected and interdependent elements, the influences generated by them originate emergent properties and behaviors for the whole that, individually studied, would not make sense. We believe that the design of cities cannot remain oblivious to these principles, and therefore this research aims to demonstrate the potential that they have for decision-making in the urban environment. Thus, we will see an example of action in the field of public mobility, another example in the design of commercial areas, and a third example in the field of redensification of sprawl areas, in which different aspects of network theory have been applied to change the urban design. We think that even though these actions have been developed in European cities, and more specifically in the Mediterranean area in Spain, the reflections and tools could have a broader scope of action.

Keywords: graphs, complexity sciences, urban networks, urban design

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786 Business Marketing Researches and Analysis Effect on Production

Authors: Mirna John Shawky Demian

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Internal marketing changed into proposed in the 1970s. The idea has continually been modified over the last forty years. This study discussed the subsequent troubles: the definition and implication of internal advertising, the improvement of its development, and the evolution of its theoretical version. Moreover, the study systematically organized the strategies of the inner advertising and marketing principles adopted in an organization and the way they were positioned in exercise. Also, in contrast, the empirical research focuses on how the existent theories prompted the essential variables of internal marketing. The results of this are predicted to serve as references for future exploration of the boundary and research aiming at how internal advertising and marketing are applied to one-of-a-kind styles of organizations. Information technology (IT) has prevailed over all capabilities of strategic and operational control. The internet has increasingly grown to be a famous medium for advertising and marketing. This paper examines the potential of the internet for tourism marketing. To acquire this, the paper examines the characteristics of tourism advertising and examines the application of the Internet in tourism advertising. It's far argued that using the internet for tourism advertising will now not only reach a wide target audience and reduce the price of transactions (with the aid of traditional strategies utilized by journey agents in instances past) but will even alleviate the problems of identity, authentication and affirmation of travels/package deal excursions by way of travelers as well as advertising of tourism enterprises.

Keywords: direct marketing, mobile phones mobile marketing, sms advertising, marketing sponsorship, marketing communication theories, marketing communication tools

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785 A Unique Professional Development of Teacher Educators: Teaching Colleagues

Authors: Naomi Weiner-Levy

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The Mofet Institute of Research, established a School of Professional Development, the only one of its kind in Israel and throughout the world. It offers specialized programs for teacher educators, providing them with the professional knowledge and skills. The studies aim at updating teachers about rapidly changing knowledge and skills. Teacher educators are conceptualized as shifting from first order practitioners (school teachers) to second order practitioners. Those who train teachers are referred to as third order practitioners. The instructors in the School of Professional Development are third-order practitioners – teacher educators specializing in teaching their colleagues. Collegial guidance by teachers’ college staff members is no simple task: Tutors must be expert in their field of specialization, as well as in instruction. Moreover, although colleagues, they have to position themselves within the group as authoritative figures in terms of instruction and knowledge. To date, the role and professional identity of these third-order practitioners, has not been studied. To understand the nature and development of professional identity, a qualitative study was conducted in which 12 tutors of various subjects were interviewed. These were analyzed by categorical content analysis. The findings, assessed professional identity through a post-modern prism, while examining the interplay among events that tutors experienced, the knowledge they acquired and the structuring of their professional identity. The Tutors’ identity transformed through negotiating with ‘self’ and ‘other’ in the class, and constructed by their mutual experiences as tutors and learners. Understanding the function and identity of tutors facilitates comprehension of this unique training process for teacher educators.

Keywords: professional development, professional identity, teacher education, tutoring

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784 Organic Agriculture Harmony in Nutrition, Environment and Health: Case Study in Iran

Authors: Sara Jelodarian

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Organic agriculture is a kind of living and dynamic agriculture that was introduced in the early 20th century. The fundamental basis for organic agriculture is in harmony with nature. This version of farming emphasizes removing growth hormones, chemical fertilizers, toxins, radiation, genetic manipulation and instead, integration of modern scientific techniques (such as biologic and microbial control) that leads to the production of healthy food and the preservation of the environment and use of agricultural products such as forage and manure. Supports from governments for the markets producing organic products and taking advantage of the experiences from other successful societies in this field can help progress the positive and effective aspects of this technology, especially in developing countries. This research proves that till 2030, 25% of the global agricultural lands would be covered by organic farming. Consequently Iran, due to its rich genetic resources and various climates, can be a pioneer in promoting organic products. In addition, for sustainable farming, blend of organic and other innovative systems is needed. Important limitations exist to accept these systems, also a diversity of policy instruments will be required to comfort their development and implementation. The paper was conducted to results of compilation of reports, issues, books, articles related to the subject with library studies and research. Likewise we combined experimental and survey to get data.

Keywords: develop, production markets, progress, strategic role, technology

Procedia PDF Downloads 117
783 A Call for Justice and a New Economic Paradigm: Analyzing Counterhegemonic Discourses for Indigenous Peoples' Rights and Environmental Protection in Philippine Alternative Media

Authors: B. F. Espiritu

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This paper examines the resistance of the Lumad people, the indigenous peoples in Mindanao, Southern Philippines, and of environmental and human rights activists to the Philippine government's neoliberal policies and their call for justice and a new economic paradigm that will uphold peoples' rights and environmental protection in two alternative media online sites. The study contributes to the body of knowledge on indigenous resistance to neoliberal globalization and the quest for a new economic paradigm that upholds social justice for the marginalized in society, empathy and compassion for those who depend on the land for their survival, and environmental sustainability. The study analyzes the discourses in selected news articles from Davao Today and Kalikasan (translated to English as 'Nature') People's Network for the Environment’s statements and advocacy articles for the Lumad and the environment from 2018 to February 2020. The study reveals that the alternative media news articles and the advocacy articles contain statements that expose the oppression and violation of human rights of the Lumad people, farmers, government environmental workers, and environmental activists as shown in their killings, illegal arrest and detention, displacement of the indigenous peoples, destruction of their schools by the military and paramilitary groups, and environmental plunder and destruction with the government's permit for the entry and operation of extractive and agribusiness industries in the Lumad ancestral lands. Anchored on Christian Fuch's theory of alternative media as critical media and Bert Cammaerts' theorization of alternative media as counterhegemonic media that are part of civil society and form a third voice between state media and commercial media, the study reveals the counterhegemonic discourses of the news and advocacy articles that oppose the dominant economic system of neoliberalism which oppresses the people who depend on the land for their survival. Furthermore, the news and advocacy articles seek to advance social struggles that transform society towards the realization of cooperative potentials or a new economic paradigm that upholds economic democracy, where the local people, including the indigenous people, are economically empowered their environment and protected towards the realization of self-sustaining communities. The study highlights the call for justice, empathy, and compassion for both the people and the environment and the need for a new economic paradigm wherein indigenous peoples and local communities are empowered towards becoming self-sustaining communities in a sustainable environment.

Keywords: alternative media, environmental sustainability, human rights, indigenous resistance

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782 Effect of Naameh Landfill (Lebanon) on Groundwater Quality of the Surrounding Area

Authors: Rana Sawaya, Jalal Halwani, Isam Bashour, Nada Nehme

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Mismanagement of municipal solid wastes in Lebanon might lead to serious environmental problems, especially that a big portion of mixed wastes including putrescible is transferred to Naameh landfill. One of the consequences of municipal solid waste deposition is the production of landfill leachate, which if unproperly treated will threaten the main crucial matrices such as soil, water, and air. The main aim of this one of a kind study is to assess the risk posed to groundwater as a result of leachate infiltration on off-site wells especially after stoppage of Naameh landfill's operation end of the year 2016 and initiation of the capping process which is still ongoing and will be finalized in December 2019. For this purpose, nine representative points around the landfill were selected to undergo physicochemical and microbial analysis on a seasonal basis (every three months). The study extended from the year 2014 until the end of the year 2016 (closure of Naameh landfill). The preliminary data obtained are statistically analyzed using the Statistical Package for Social Sciences (SPSS) and was found in conformity with international and Lebanese norms. Thus, the study will be extended an additional year, especially after the finalization of capping and the results obtained, will enable us to propose new techniques and tools (treatment systems) in water resources management depending on the direction of its usage (domestic, irrigation, drinking).

Keywords: contamination, groundwater, leachate, Lebanon, solid waste

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781 Teaching Students Empathy: Justifying Diverse and Inclusive Texts

Authors: Jennifer Wallbrown

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It’s not uncommon in the US to see news article headlines about public school teachers being scrutinized for what they are teaching or see the general public weighing in on whether or not they think certain controversial subjects should be addressed in the classroom- such as LGBTQ+ or multicultural literature. Even though this is a subject that has been written about and discussed for years, it continues to be a relevant topic in education as it continues to be a struggle to implement more diverse texts. Although it is valid for teachers to fear controversy when they attempt to create a more diverse or inclusive curriculum, it is a fight worth fighting because of the benefits students can gain from being exposed to a wide range of texts. This paper is different from others of its kind because it addresses many of the counterarguments often made to implementing LGBTQ+ or multicultural literature in secondary classrooms. It not only encourages educators to try to include more diverse texts, but it gives them the tools to address common concerns and be sound in their reasoning for choosing these texts. This can be of interest to those educators who are not English teachers because a truly diverse and inclusive curriculum would include other subjects as well- including history, art, and more. By the end of my proposed paper, readers will feel encouraged to choose more diverse and inclusive texts for their classrooms. They can also be confident that if met with opposition or controversy, as is sometimes common when implementing new texts, that they have sound arguments and reasoning for why they chose to include these texts. This reasoning is that, based on the research, studies have found there are benefits to students studying texts about those different from themselves, because it teaches them empathy and helps fight prejudice.

Keywords: education, diverse, inclusive, multicultural, lgbtq+, pedagogy

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780 Reconstructing Calvarial Bone Lesions Using PHBV Scaffolds and Cord Blood Mesenchymal Stem Cells in Rat

Authors: Hamed Hosseinkazemi, Esmaeil Biazar

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For tissue engineering of bone, anatomical and operational reconstructions of damaged tissue seem to be vital. This is done via reconstruction of bone and appropriate biological joint with bone tissues of damaged areas. In this study the condition of biodegradable bed Nanofibrous PHBV and USSC cells were used to accelerate bone repair of damaged area. Hollow nanofabrication scaffold of damageable life was designed as PHBV by electrospinning and via determining the best factors such as the kind and amount of solvent, specific volume and rate. The separation of osseous tissue infiltration and evaluating its nature by flow cytometrocical analysis was done. Animal test including USSC as well as PHBV condition in the damaged bone was done in the rat. After 8 weeks the implanted area was analyzed using CT scan and was sent to histopathology ward. Finally, the rate and quality of reconstruction were determined after H and E coloring. Histomorphic analysis indicated a statistically significant difference between the experimental group of PHBV, USSC+PHBV and control group. Besides, the histopathologic analysis showed that bone reconstruction rate was high in the area containing USSC and PHBV, compared with area having PHBV and control group and consequently the reconstruction quality of bones and the relationship between the new bone tissues and surrounding bone tissues were high too. Using PHBR scaffold and USSC together could be useful in the amending of wide range of bone lesion.

Keywords: bone lesion, nanofibrous PHBV, stem cells, umbilical cord blood

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779 Effect of Pre-bonding Storage Period on Laser-treated Al Surfaces

Authors: Rio Hirakawa, Christian Gundlach, Sven Hartwig

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In recent years, the use of aluminium has further expanded and is expected to replace steel in the future as vehicles become lighter and more recyclable in order to reduce greenhouse gas (GHG) emissions and improve fuel economy. In line with this, structures and components are becoming increasingly multi-material, with different materials, including aluminium, being used in combination to improve mechanical utility and performance. A common method of assembling dissimilar materials is mechanical fastening, but it has several drawbacks, such as increased manufacturing processes and the influence of substrate-specific mechanical properties. Adhesive bonding and fusion bonding are methods that overcome the above disadvantages. In these two joining methods, surface pre-treatment of the substrate is always necessary to ensure the strength and durability of the joint. Previous studies have shown that laser surface treatment improves the strength and durability of the joint. Yan et al. showed that laser surface treatment of aluminium alloys changes α-Al2O3 in the oxide layer to γ-Al2O3. As γ-Al2O3 has a large specific surface area, is very porous and chemically active, laser-treated aluminium surfaces are expected to undergo physico-chemical changes over time and adsorb moisture and organic substances from the air or storage atmosphere. The impurities accumulated on the laser-treated surface may be released at the adhesive and bonding interface by the heat input to the bonding system during the joining phase, affecting the strength and durability of the joint. However, only a few studies have discussed the effect of such storage periods on laser-treated surfaces. This paper, therefore, investigates the ageing of laser-treated aluminium alloy surfaces through thermal analysis, electrochemical analysis and microstructural observations.AlMg3 of 0.5 mm and 1.5 mm thickness was cut using a water-jet cutting machine, cleaned and degreased with isopropanol and surface pre-treated with a pulsed fibre laser at 1060 nm wavelength, 70 W maximum power and 55 kHz repetition frequency. The aluminium surface was then analysed using SEM, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and cyclic voltammetry (CV) after storage in air for various periods ranging from one day to several months TGA and FTIR analysed impurities adsorbed on the aluminium surface, while CV revealed changes in the true electrochemically active surface area. SEM also revealed visual changes on the treated surface. In summary, the changes in the laser-treated aluminium surface with storage time were investigated, and the final results were used to determine the appropriate storage period.

Keywords: laser surface treatment, pre-treatment, adhesion, bonding, corrosion, durability, dissimilar material interface, automotive, aluminium alloys

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778 Review Architectural Standards in Design and Development Children's Educational Centers

Authors: Ahmad Torkaman, Suogol Shomtob, Hadi Akbari Seddigh

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In this paper it has been attempted to investigate the lack of attention to how specific spatial characteristics of the children except existing places such as nurseries. In order to achieve the standard center to faster children understanding their mentality is the first issue that must be studied. Exploring the spiritual characteristics and complexities of children cannot be possible except in accordance with the different aspects and background of their growth in various age periods. In order to achieving the standard center for fostering children, the first issue that must be studied understands their mentality. Exploring the spiritual qualities and complexities of children are not provided except in accordance with the characteristics and their different growth backgrounds in different age periods. According to previous researches game or playing is the most important activity that helps children to communicate and educate and sometimes therapy in specific fields. Investigating game as a proper way to train, the variety of games, the various kind of play environment and how to treat some abnormalities thereby are the issues discussed in recent research. Another consideration concerns the importance of artistic activities among children which is very evident in studying identification of their abnormalities. At the end of this study after investigating how to understand child and communicate with him/her, aiming to recognize Specific spatial characteristics for better training children, the physical and physiological criteria and characteristics is Reviewed and ends up to a list of required spaces and dimensional characteristic of spaces and needed children's equipment.

Keywords: children, space, interior design, development, growth

Procedia PDF Downloads 333
777 Reservoir Inflow Prediction for Pump Station Using Upstream Sewer Depth Data

Authors: Osung Im, Neha Yadav, Eui Hoon Lee, Joong Hoon Kim

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Artificial Neural Network (ANN) approach is commonly used in lots of fields for forecasting. In water resources engineering, forecast of water level or inflow of reservoir is useful for various kind of purposes. Due to advantages of ANN, many papers were written for inflow prediction in river networks, but in this study, ANN is used in urban sewer networks. The growth of severe rain storm in Korea has increased flood damage severely, and the precipitation distribution is getting more erratic. Therefore, effective pump operation in pump station is an essential task for the reduction in urban area. If real time inflow of pump station reservoir can be predicted, it is possible to operate pump effectively for reducing the flood damage. This study used ANN model for pump station reservoir inflow prediction using upstream sewer depth data. For this study, rainfall events, sewer depth, and inflow into Banpo pump station reservoir between years of 2013-2014 were considered. Feed – Forward Back Propagation (FFBF), Cascade – Forward Back Propagation (CFBP), Elman Back Propagation (EBP) and Nonlinear Autoregressive Exogenous (NARX) were used as ANN model for prediction. A comparison of results with ANN model suggests that ANN is a powerful tool for inflow prediction using the sewer depth data.

Keywords: artificial neural network, forecasting, reservoir inflow, sewer depth

Procedia PDF Downloads 317
776 Correlating Musical Subject and Dialectical Subject to Develop a Critical Approach to Ideology in Musical Analysis and Composition

Authors: James Waide

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In music, subject typically denotes the initial idea to which the entire composition refers—a concept congruous with Aristotle's notion of subject as primary substance, in the sense of an irreducible this particular. Gioseffo Zarlino, who established subject (soggetto) as a musical term, insisted the composer as “rediscovering” the subject within their music in order to “[bring] it to perfection” and, furthermore, that if the composer had not rediscovered the subject already, then one would simply take the first part of the composition to be the subject. Meanwhile, Žižek reads the Hegelian subject (as negativity set against positive object) through Lacanian Psychoanalysis (in which the subject is a kind of fictive entity of the clinic: a mere appearance which sits atop the objects of analysis) in the concept of Absolute Recoil. For Žižek, subject exists retroactively in Absolute Recoil from object, meaning subject is a void which only has meaning because of the object it is seen through. Following the work of theorists such as Adorno and Althusser, one can understand the ideological construction of such a subject. It may be argued that in Zarlino, musical subject can be similarly read as retroactively constructed, either by the composer or the listener. Furthermore, in recent work, Samuel Wilson identifies different kinds of subjects in music which can be psychoanalytically examined, including the fictive subject: a purely musical entity raised to the level of psychoanalytic subject. On which basis if, as Adorno insisted, 'authentic' music constitutes 'cognition without concepts', where and what is this subject without concept?.

Keywords: absolute recoil, critical theory, ideology, music analysis, psychoanalysis, retroactivity, subject

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775 The Impact of Biodiversity and Urban Ecosystem Services in Real Estate

Authors: Carmen Cantuarias-Villessuzanne, Jeffrey Blain, Radmila Pineau

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Our research project aims at analyzing the sensitiveness of French households to urban biodiversity and urban ecosystem services (UES). Opinion surveys show that the French population is sensitive to biodiversity and ecosystem services loss, but the value given to these issues within urban fabric and real estate market lacks evidence. Using GIS data and economic evaluation, by hedonic price methods, weassess the isolated contribution of the explanatory variables of biodiversityand UES on the price of residential real estate. We analyze the variation of the valuefor three urban ecosystem services - flood control, proximity to green spaces, and refreshment - on the price of real estate whena property changes ownership. Our modeling and mapping focus on the price at theIRIS scale (statistical information unit) from 2014 to 2019. The main variables are internal characteristics of housing (area, kind of housing, heating), external characteristics(accessibility and infrastructure, economic, social, and physical environmentsuch as air pollution, noise), and biodiversity indicators and urban ecosystemservices for the Ile-de-France region. Moreover, we compare environmental values on the enhancement of greenspaces and their impact on residential choices. These studies are very useful for real estate developers because they enable them to promote green spaces, and municipalities to become more attractive.

Keywords: urban ecosystem services, sustainable real estate, urban biodiversity perception, hedonic price, environmental values

Procedia PDF Downloads 132
774 The Effects of Self-Reflections on Intercultural Communication Competency: A Case Study of the University of Arkansas-Fort Smith

Authors: JaeYoon Park

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The ability to communicate effectively across different cultures is a necessary skill in today’s increasingly globalized world. Intercultural communication competency (ICC) is a way of being that benefits all members of a society in their living, learning, and working environments as well as in the context of mediated communications. This study examines the effects of self-reflection processes on the improvement of intercultural communication skills focusing on college students at the University of Arkansas-Fort Smith. A total of sixty-nine students’ works were analyzed based on the data collected in the past three years (2016, 2017 and 2018). The students in the ‘Culture and Communication’ class, each spring, completed the Diversity Awareness Profile (DAP) survey as a pre- and post-test for the course. DAP is a self-assessment tool designed by Karen Stinson and widely used in college classes, companies, and organizations to evaluate an individual’s behaviors in various intercultural settings. It can assist individuals in becoming more aware of diversity issues and also provide a foundation for developing strategies for modifying any undesirable behavior they may discover in the assessment. In addition to the DAP surveys, the students also submitted self-reflection essays that discussed their own scores. The University of Arkansas-Fort Smith is a small regional university located in the Bible Belt of the United States. White, Christian, working-class students dominate its student population. The students, whose data were collected, were predominantly seniors in college majoring in either Media Communication or International Business. Approximately, 80% of the students increased their scores, and 42% of them moved forward to a new category. The findings also indicate that the students in the underrepresented groups (i.e., women, minority, and international students) show less change in their scores and behaviors than the rest of the students (i.e., white heterosexual male students). These findings, in most part, result from the fact that the underrepresented students were already aware of diversity and intercultural issues through their personal experiences before taking the class. The white heterosexual male students demonstrated the greatest improvements, judging from their DAP scores (pre- and post-tests) and self-reflection essays. Through the class assignments and discussions, which emphasized critical thinking and self-reflection, the latter group of students not only became more aware of the meaning of their own words and behaviors, but they were also able to develop greater proficiency in intercultural communication. This e-poster presentation will analyze the findings of this research data, and also discuss the pedagogical implications of such results.

Keywords: cross-cultural communication, diversity awareness survey, self-reflection, underrepresented students

Procedia PDF Downloads 121
773 Accelerated Molecular Simulation: A Convolution Approach

Authors: Jannes Quer, Amir Niknejad, Marcus Weber

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Computational Drug Design is often based on Molecular Dynamics simulations of molecular systems. Molecular Dynamics can be used to simulate, e.g., the binding and unbinding event of a small drug-like molecule with regard to the active site of an enzyme or a receptor. However, the time-scale of the overall binding event is many orders of magnitude longer than the time-scale of simulation. Thus, there is a need to speed-up molecular simulations. In order to speed up simulations, the molecular dynamics trajectories have to be ”steared” out of local minimizers of the potential energy surface – the so-called metastabilities – of the molecular system. Increasing the kinetic energy (temperature) is one possibility to accelerate simulated processes. However, with temperature the entropy of the molecular system increases, too. But this kind ”stearing” is not directed enough to stear the molecule out of the minimum toward the saddle point. In this article, we give a new mathematical idea, how a potential energy surface can be changed in such a way, that entropy is kept under control while the trajectories are still steared out of the metastabilities. In order to compute the unsteared transition behaviour based on a steared simulation, we propose to use extrapolation methods. In the end we mathematically show, that our method accelerates the simulations along the direction, in which the curvature of the potential energy surface changes the most, i.e., from local minimizers towards saddle points.

Keywords: extrapolation, Eyring-Kramers, metastability, multilevel sampling

Procedia PDF Downloads 328