Search results for: load settlement behavior

Authors: Mojdeh Mohseni

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In the context of tissue engineering, the effect of microtopography as afforded by scaffold morphology is an important design parameter. Since the morphology of pores can effect on cell behavior, in this study, porous Chitosan (CHIT) - Gelatin (GEL)- Alginate (ALG) scaffolds with microtubule orientation structure were manufactured by unidirectional freeze-drying method and the effect of pore morphology on differentiation of Mesenchymal Stem Cells (MSCs) was investigated. This study showed that, the provided scaffold with natural polymer had good properties for cell behavior and the pores with highest orientation rate have produced appropriate substrate for the differentiation of stem cells.

Keywords: Chitosan, gelatin, Alginate, pore morphology, stem cell differentiation

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Authors: Phan Hong, David Lishner, Matthew Hanson

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Sixty-five children across four school research sites participated in the present experiment, which was designed to examine whether mindfulness promotes eating enjoyment and diverse eating behaviors in preschool- and early elementary-age children. Children, ages 3-9 years old, were randomly assigned to a 4-week mindfulness intervention condition or a 4-week exposure, control condition. Each week for four days, children received one of four different foods (celery, cauliflower, kidney beans, or garbanzo beans). Children either received instructions to mindfully engage with the food or were given the food and allowed to eat without mindfulness prompts from the researchers. Following the eating exercise, they recorded the amount eaten and rated their enjoyment level. Across all sessions, researchers modeled eating behaviors for the children by eating all the offered food. Results suggested that a brief mindfulness intervention promoted more diverse eating behaviors and more overall food consumption of typically not preferred and unfamiliar foods (celery, cauliflower, and garbanzo beans), compared with an exposure, control condition in preschool children and elementary-age children. However, food enjoyment ratings did not significantly differ between the two conditions for any of the foods. Implications of the finding for addressing eating behavior of young children are considered.

Keywords: children, control trial, eating behavior, eating enjoyment, mindfulness, schools

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Authors: Bhawna Verma

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Looking at the contraceptive use and unmet need specific to the different age groups would help to understand various determinants and characteristics of women from different age groups, which are often being neglected. The study explores contraceptive behavior, unmet need for family planning and its correlates among young nulliparous women aged 15-29, using data from NFHS-4 (2015-16), India. Method: The study utilized information from 26,924 currently married women, who has no child or who have had first terminated pregnancy and was aged 15-29 at the time of the survey. Chi-Square and logistic regression analysis have been used to assess the effects of socio-economic characteristics. Results: Of all the considered explanatory variables religion, caste, education, current age, age at marriage, media exposure and regional differences were found to be significantly affecting the behavior of contraceptive use. Women of the 25-29 age group are 0.6 percent less likely to have an unmet need than women of 12-19 age group. Unmet need is increasing with the increased level of education. Muslim women are 0.3 percent less likely to have an unmet need than women of Hindu category. Conclusion: Separate considerations must be given to the needs for family planning formation among nulliparous women along with the factors associated with the use and non-use of contraceptives among them. Separate considerations must be given for effective promotion of FP knowledge through print, electronic media, towards the unequal access to the contraceptives among nulliparous women. Marriages after legal minimum age and encouraging women for higher education may address existing socio-economic barriers.

Keywords: contraceptive use, unmet need, family planning, contraceptive behavior

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Authors: Velly Anatasia

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In the last few decades extensive research has been conducted into information technology (IT) adoption, testing a series of factors considered to be essential for improved diffusion. Some studies analyze IT characteristics such as usefulness, ease of use and/or security, others focus on the emotions and experiences of users and a third group attempts to determine the importance of socioeconomic user characteristics such as gender, educational level and income. The situation is similar regarding e-commerce, where the majority of studies have taken for granted the importance of including these variables when studying e-commerce adoption, as these were believed to explain or forecast who buys or who will buy on the internet. Nowadays, the internet has become a marketplace suitable for all ages and incomes and both genders and thus the prejudices linked to the advisability of selling certain products should be revised. The objective of this study is to test whether the socioeconomic characteristics of experienced e-shoppers such as gender rally moderate the effect of their perceptions of online shopping behavior. Current development of the online environment and the experience acquired by individuals from previous e-purchases can attenuate or even nullify the effect of these characteristics. The individuals analyzed are experienced e-shoppers i.e. individuals who often make purchases on the internet. The Technology Acceptance Model (TAM) was broadened to include previous use of the internet and perceived self-efficacy. The perceptions and behavior of e-shoppers are based on their own experiences. The information obtained will be tested using questionnaires which were distributed and self-administered to respondent accustomed using internet. The causal model is estimated using structural equation modeling techniques (SEM), followed by tests of the moderating effect of socioeconomic variables on perceptions and online shopping behavior. The expected findings of this study indicated that gender moderate neither the influence of previous use of the internet nor the perceptions of e-commerce. In short, they do not condition the behavior of the experienced e-shopper.

Keywords: Internet shopping, age groups, gender, income, electronic commerce

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Authors: Bian ChengXiang, Wang Qian

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With the deepening of the research on the connotation of cultural heritage and human geography, the cultural landscape takes landscape as a cultural product, integrates and blends cultural and natural heritage to explore the cultural value behind its material landscape. Qikou ancient town is a typical traditional settlement with a homomorphism of mountain and water veins. Its cultural accumulation and natural landscape play an important role in its development. Therefore, this paper will combine the material and cultural elements of Qikou ancient town to analyze the composition of the cultural landscape of the ancient town and explore the protection and utilization of the cultural landscape of Qikou ancient town from the four aspects of ecology, form, cultural form, and business form, so as to provide effective strategies for the development of the ancient town.

Keywords: four state, cultural landscape, ancient town, protection, development

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Authors: Chun-Lin Zhang, Min Wan

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With the upgrade development of the tourism industry from the simple sightseeing tour to the leisure and vacation, people's travel idea has undergone a fundamental change. More and more people begin to pursue liberal and personal tourism, so self-driving tourism has become the main form of current tourism activities. With the self-driving tourism representing the general trend, the importance of convenient tourism transportation and perfect road traffic signs have become more and more prominent. A clear urban road traffic signs can help visitors quickly identify the direction and distance to the tourism destination. The purpose of this article is analyzing the planning of urban road traffic signs which can bring positive impact on the participation in the recreation involved of self-driving tourists. The content of this article is divided into three parts. Based on the literature review and theoretical analysis, the first part constructs a structural variance model. The model is from three dimensions: the attention of the self-driving tourists to the urban traffic signs along the road, the perception of the self-driving tourists to the road traffic signs itself, the perceptions of the self-driving tourists to the tourism destination information on the traffic signs. Through this model, the paper aims to explore the influence of the urban road traffic signs to the leisure psychological involvement and leisure behavior involvement of the self-driving tourists. The second part aims to verify through the hypothesis model the questionnaire survey and come to preliminary conclusions. The preliminary conclusions are as follows: firstly, the color, shape, size, setting mode and occurrence frequency of urban road traffic sign have significant influence on the leisure psychological involvement and leisure behavior involvement of the self-driving tourists. Secondly, the influence on the leisure behavior involvement is obviously higher than the influence on the leisure psychological involvement. Thirdly, the information about the tourism destination marked on the urban road traffic signs has not obviously influence on the leisure psychological involvement, but it has distinct influence on the leisure behavior involvement of self-driving tourists. The third part puts forward that the planning of urban road traffic signs should focus on the angle of the impact of road traffic signs on people's psychology and behavior. On the basis of the above conclusions, the paper researches the color, shape, size, setting mode and information labeling of urban road traffic signs so that they can preferably satisfy the demand of the leisure involvement of self-driving tourists.

Keywords: leisure involvement, self-driving tourism, structural equation, urban road traffic signs

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Authors: Nicolas Bigot, M'hamed Boutaous, Nahiene Hamila, Shihe Xin

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Composite materials with polymer matrices are widely used in most industrial areas, particularly in aeronautical and automotive ones. Thanks to the development of a high-performance thermoplastic semicrystalline polymer matrix, those materials exhibit more and more efficient properties. The polymer matrix in composite materials can manifest a specific crystalline structure characteristic of crystallization in a fibrous medium. In order to guarantee a good mechanical behavior of structures and to optimize their performances, it is necessary to define realistic mechanical constitutive laws of such materials considering their physical structure. The interaction between fibers and matrix is a key factor in the mechanical behavior of composite materials. Transcrystallization phenomena which develops in the matrix around the fibers constitute the interphase which greatly affects and governs the nature of the fiber-matrix interaction. Hence, it becomes fundamental to quantify its impact on the thermo-mechanical behavior of composites material in relationship with processing conditions. In this work, we propose a numerical model coupling the thermal and crystallization kinetics in long fiber-based composite materials, considering both the spherulitic and transcrystalline types of the induced structures. After validation of the model with comparison to results from the literature and noticing a good correlation, a parametric study has been led on the effects of the thermal kinetics, the fibers volume fractions, the deformation, and the pressure on the crystallization rate in the material, under processing conditions. The ratio of the transcrystallinity is highlighted and analyzed with regard to the thermal kinetics and gradients in the material. Experimental results on the process are foreseen and pave the way to establish a mechanical constitutive law describing, with the introduction of the role on the crystallization rates and types on the thermo-mechanical behavior of composites materials.

Keywords: composite materials, crystallization, heat transfer, modeling, transcrystallization

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Authors: Timothy O. Adekunle, Sigridur Bjarnadottir

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Several studies have investigated thermal behavior of buildings with limited studies focusing on high-rise buildings. Of the limited investigations that have considered thermal performance of high-rise buildings, only a few studies have considered thermal behavior of high-rise structural sustainable buildings. As a result, this study investigates the thermal behavior of a high-rise structural timber building. The study aims to understand the thermal environment of a high-rise structural timber block of apartments located in East London, UK by comparing the indoor environmental conditions at different floors (ground and upper floors) of the building. The environmental variables (temperature and relative humidity) were measured at 15-minute intervals for a few weeks in the summer of 2012 to generate data that was considered for calibration and validation of the simulated results. The study employed mainly dynamic thermal building simulation using DesignBuilder by EnergyPlus and supplemented with environmental monitoring as major techniques for data collection and analysis. The weather file (Test Reference Years- TRYs) for the 2000s from the weather generator carried out by the Prometheus Group was considered for the simulation since the study focuses on investigating thermal behavior of high-rise structural timber buildings in the summertime and not in extreme summertime. In this study, the simulated results (May-September of the 2000s) will be the focus of discussion, but the results will be briefly compared with the environmental monitoring results. The simulated results followed a similar trend with the findings obtained from the short period of the environmental monitoring at the building. The results revealed lower temperatures are often predicted (at least 1.1°C lower) at the ground floor than the predicted temperatures at the upper floors. The simulated results also showed that higher temperatures are predicted in spaces at southeast facing (at least 0.5°C higher) than spaces in other orientations across the floors considered. There is, however, a noticeable difference between the thermal environment of spaces when the results obtained from the environmental monitoring are compared with the simulated results. The field survey revealed higher temperatures were recorded in the living areas (at least 1.0°C higher) while higher temperatures are predicted in bedrooms (at least 0.9°C) than living areas for the simulation. In addition, the simulated results showed spaces on lower floors of high-rise structural timber buildings are predicted to provide more comfortable thermal environment than spaces on upper floors in summer, but this may not be the same in wintertime due to high upward movement of hot air to spaces on upper floors.

Keywords: building simulation, high-rise, structural timber buildings, sustainable, temperatures, thermal behavior

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Authors: Nour Charara, Hussein Charara, Omar Abou Khaled, Hani Abdallah, Elena Mugellini

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In this paper, we present a human behavior modeling approach in videos scenes. This approach is used to model the normal behaviors in the conference halls. We exploited the Probabilistic Latent Semantic Analysis technique (PLSA), using the 'Bag-of-Terms' paradigm, as a tool for exploring video data to learn the model by grouping similar activities. Our term vocabulary consists of 3D spatio-temporal patch groups assigned by the direction of motion. Our video representation ensures the spatial information, the object trajectory, and the motion. The main importance of this approach is that it can be adapted to detect abnormal behaviors in order to ensure and enhance human security.

Keywords: activity modeling, clustering, PLSA, video representation

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Authors: Ferhat Erdal, Osman Tunca, Serkan Tas, Serdar Carbas

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Web-expanded steel beams provide an easy and economical solution for the systems having longer structural members. The main goal of manufacturing these beams is to increase the moment of inertia and section modulus, which results in greater strength and rigidity. Until recently, there were two common types of open web-expanded beams: with hexagonal openings, also called castellated beams, and beams with circular openings referred to as cellular beams, until the generation of sinusoidal web-expanded beams. In the present research, the optimum design of a new generation beams, namely sinusoidal web-expanded beams, will be carried out and the design results will be compared with castellated and cellular beam solutions. Thanks to a reduced fabrication process and substantial material savings, the web-expanded beam with sinusoidal holes (Angelina™ Beam) meets the economic requirements of steel design problems while ensuring optimum safety. The objective of this research is to carry out non-linear finite element analysis (FEA) of the web-expanded beam with sinusoidal holes. The FE method has been used to predict their entire response to increasing values of external loading until they lose their load carrying capacity. FE model of each specimen that is utilized in the experimental studies is carried out. These models are used to simulate the experimental work to verify of test results and to investigate the non-linear behavior of failure modes such as web-post buckling, shear buckling and vierendeel bending of beams.

Keywords: steel structures, web-expanded beams, angelina beam, optimum design, failure modes, finite element analysis

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Authors: Santi Termprasertsakul, Jakkrich Jearviriyaboonya

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This paper studies the market power and pricing behavior of products in iron and steel industry by investigating the impact of vertical product differentiation (VPD) on exchange rate pass-through (ERPT). Vietnam has become one of the major trading partners of Thailand since 2017. The iron and steel export value to Vietnam is more than $300 million a year. Particularly, the average growth rate of importing iron and steel is approximately 30% per year. The VPD is applied to analyze the quality difference of iron and steel between Thailand and Vietnam. The 20 products in iron and steel industry are investigated. The monthly pricing behavior of Harmonized Commodity Description and Coding System 4-digit products is observed from 2010 to 2019. The Nonlinear Autoregressive Distributed Lag is also used to analyze the asymmetry of ERPT in this paper. The empirical results basically reveal an incomplete pass-through between Thai Baht and Vietnamese Dong. The ERPT also varies with the degree of VPD. The product with higher VPD, indicating higher unit values, has higher ERPT. This result suggests the higher market power of the Thai iron and steel industry. In addition, the asymmetry of ERPT exists.

Keywords: exchange rate pass-through, iron and steel industry, pricing behavior, vertical product differentiation

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Authors: Hussain Jiffry, Kypros Pilakoutas, Reyes Garcia Lopez

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This study examines the effect of tsunami loads on reinforced concrete (RC) frame buildings analytically. The impact of tsunami wave loads and waterborne objects are analyzed using a typical substandard full-scale two-story RC frame building tested as part of the EU-funded Ecoleader project. The building was subjected to shake table tests in bare condition and subsequently strengthened using Carbon Fiber Reinforced Polymers (CFRP) composites and retested. Numerical models of the building in both bare and CFRP-strengthened conditions are calibrated in DRAIN-3DX software to match the test results. To investigate the response of wave loads and impact forces, the numerical models are subjected to nonlinear dynamic analyses using force-time history input records. The analytical results are compared in terms of displacements at the floors and the 'impact point' of a boat. The results show that the roof displacement of the CFRP-strengthened building reduced by 63% when compared to the bare building. The results also indicate that strengthening only the mid-height of the impact column using CFRP is more efficient at reducing damage when compared to strengthening other parts of the column. Alternative solutions to mitigate damage due to tsunami loads are suggested.

Keywords: tsunami loads, hydrodynamic load, impact load, waterborne objects, RC buildings

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Authors: Husam El-Asfour, Fateh Adhnouss, Kenneth McIsaac, Abdul Mutalib Wahaishi, Raafat Aburukba, Idris El-Feghia

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Although intelligence is commonly referred to as the observable behavior in various fields and domains, it must also be shown how it develops by exhibiting multiple forms and without observing the inherent behavior. There have been several official and informal definitions of intelligence in various areas; however, no scientific agreement on a definition has been agreed upon. There must be a single definition, structure, and precise modeling for articulating how intelligence is perceived by people and machines in order to comprehend intelligence. Another key challenge is defining the different environment types based on the integral elements (agents) and their possible interactions. On the basis of conceptualization, this paper proposes a formal model for defining and developing intelligence. Forms of intelligence are derived from an ontological view, and thus intelligence is defined, described, and modeled based on the various types of environments.

Keywords: intelligence, forms, transformation, conceptualization, ontological view

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Authors: Rayed Alyousef, Tim Topper, Adil Al-Mayah

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This paper presents results of an ongoing research program at University of Waterloo to study the effect of external FRP sheet wrap confinement along a lap splice of reinforced concrete (RC) beams on their fatigue bond strength. Fatigue loading of RC beams containing a lap splice resulted in an increase in the number and width of cracks, an increase in deflection and a decrease of the bond strength between the steel rebar and the surrounding concrete. The phase of the research described here consists of monotonic and fatigue tests of thirty two reinforced concrete beam with dimensions 2200⨉350⨉250 mm. Each beam was reinforced with two 20M bars lap spliced in the constant moment region of the tension zone and two 10M bars in the compression zone outside the constant moment region. The test variables were the presence or absence of a FRP wrapping, the type of the FRP wrapping (GFRP or CFRP), the type of loading and the fatigue load range. The test results for monotonic loading showed that the stiffness of all beams was almost same, but that the FRP sheet wrapping increased the bond strength and the deflection at ultimate load. All beams tested under fatigue loading failed by a bond failure except one CFRP wrapped beam that failed by fatigue of the main reinforcement. The FRP sheet increased the bond strength for all specimens under fatigue loading.

Keywords: lap splice, bond strength, fatigue loading, FRP

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Authors: Rui Magalhães, Sohel Rana, Raul Fangueiro, Clara Gonçalves, Pedro Nunes, Gustavo Dias

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Auxetic fibrous structures and composites with negative Poisson’s ratio (NPR) have huge potential for application in ballistic protection due to their high energy absorption and excellent impact resistance. In the present research, re-entrant lozenge auxetic fibrous structures were produced through weft knitting technology using high performance polyamide and para-aramid fibres. Fabric structural parameters (e.g. loop length) and machine parameters (e.g. take down load) were varied in order to investigate their influence on the auxetic behaviours of the produced structures. These auxetic structures were then impregnated with two types of polymeric resins (epoxy and polyester) to produce composite materials, which were subsequently characterized for the auxetic behaviour. It was observed that the knitted fabrics produced using the polyamide yarns exhibited NPR over a wide deformation range, which was strongly dependant on the loop length and take down load. The polymeric composites produced from the auxetic fabrics also showed good auxetic property, which was superior in case of the polyester matrix. The experimental results suggested that these composites made from the auxetic fibrous structures can be properly designed to find potential use in the body amours for personal protection applications.

Keywords: auxetic fabrics, high performance, composites, energy absorption, impact resistance

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Authors: Chungyu Chen, Yi-Cheng Chen, Po-Hsian Hsu, Hsin-Ying Chen, Yen-Po Hsiao

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The purpose of this study was to assess the muscular strength performance of upper and lower extremity in isokinetic system for the youth judo players, and also to compare the strength difference between major techniques. Sixteen male and 20 female judo players (age: 16.7 ± 1.6 years old, training age: 4.5 ± 0.8 years) were served as the volunteers for this study. There were 21 players major hand techniques and 15 players major foot techniques. The Biodex S4 Pro was used to assess the strength performance of extensor and flexor of concentric action under the load condition of 30 degree/sec, 60 degree/sec, and 120 degree/sec for elbow joints and knee joints. The strength parameters were included the maximal torque, the normalized maximal torque, the average power, and the average maximal torque. A t test for independent groups was used to evaluate whether hand major and foot major differ significantly with an alpha level of .05. The result showed the maximal torque of left knee extensor in foot major players (243.5 ± 36.3 Nm) was higher significantly than hand major (210.7 ± 21.0 Nm) under the load of 30 degree/sec (p < .05). There were no differences in upper extremity strength between the hand and foot techniques major in three loads (ps < .05). It indicated that the judo player is required to develop the upper extremity strength overall to secure the execution of major techniques.

Keywords: knee, elbow, power, judo

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Authors: Hadi Chahal, Irini Djeran-Maigre

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This paper focuses on the hydro-mechanical behavior of polychlorinated biphenyl (PCB) polluted sediments when stored in landfills and the interaction between PCBs and geosynthetic clay liners (GCL) with respect to hydraulic performance of the liner and the overall performance and stability of landfills. A European decree, adopted in the French regulation forbids the reintroducing of contaminated dredged sediments containing more than 0,64mg/kg Σ 7 PCBs to rivers. At these concentrations, sediments are considered hazardous and a remediation process must be adopted to prevent the release of PCBs into the environment. Dredging and landfilling polluted sediments is considered an eco-environmental remediation solution. French regulations authorize the storage of PCBs contaminated components with less than 50mg/kg in municipal solid waste facilities. Contaminant migration via leachate may be possible. The interactions between PCBs contaminated sediments and the GCL barrier present in the bottom of a landfill for security confinement are not known. Moreover, the hydro-mechanical behavior of stored sediments may affect the performance and the stability of the landfill. In this article, hydro-mechanical characterization of the polluted sediment is presented. This characterization led to predict the behavior of the sediment at the storage site. Chemical testing showed that the concentration of PCBs in sediment samples is between 1.7 and 2,0 mg/kg. Physical characterization showed that the sediment is organic silty sand soil (%Silt=65, %Sand=27, %OM=8) characterized by a high plasticity index (Ip=37%). Permeability tests using permeameter and filter press showed that sediment permeability is in the order of 10-9 m/s. Compressibility tests showed that the sediment is a very compressible soil with Cc=0,53 and Cα =0,0086. In addition, effects of PCB on the swelling behavior of bentonite were studied and the hydraulic performance of the GCL in interaction with PCBs was examined. Swelling tests showed that PCBs don’t affect the swelling behavior of bentonite. Permeability tests were conducted on a 1.0 m pilot scale experiment, simulating a storage facility. PCBs contaminated sediments were directly placed over a passive barrier containing GCL to study the influence of the direct contact of polluted sediment leachate with the GCL. An automatic water system has been designed to simulate precipitation. Effluent quantity and quality have been examined. The sediment settlements and the water level in the sediment have been monitored. The results showed that desiccation affected the behavior of the sediment in the pilot test and that laboratory tests alone are not sufficient to predict the behavior of the sediment in landfill facility. Furthermore, the concentration of PCB in the sediment leachate was very low ( < 0,013 µg/l) and that the permeability of the GCL was affected by other components present in the sediment leachate. Desiccation and cracks were the main parameters that affected the hydro-mechanical behavior of the sediment in the pilot test. In order to reduce these infects, the polluted sediment should be stored at a water content inferior to its shrinkage limit (w=39%). We also propose to conduct other pilot tests with the maximum concentration of PCBs allowed in municipal solid waste facility of 50 mg/kg.

Keywords: geosynthetic clay liners, landfill, polychlorinated biphenyl, polluted dredged materials

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Authors: Iva Dvornik, Sandro Božić, Žana Božić Brkić

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System-dynamic simulating modelling is one of the most appropriate and successful scientific methods of the complex, non-linear, natural, technical and organizational systems. In the recent practice its methodology proved to be efficient in solving the problems of control, behavior, sensitivity and flexibility of the system dynamics behavior having a high degree of complexity, all these by computing simulation i.e. “under laboratory conditions” what means without any danger for observed realities. This essay deals with the research of the gas turbine dynamic process as well as the operating pump units and transformation of gas energy into hydraulic energy has been simulated. In addition, system mathematical model has been also researched (gas turbine- centrifugal pumps – pipeline pressure system – storage vessel).

Keywords: system dynamics, modelling, centrifugal pump, turbine, gases, continuous and discrete simulation, heuristic optimisation

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Authors: Ashraf Nawaz Khan, R. Alagirusamy, Apurba Das, Puneet Mahajan

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The thermoplastic-based fibre composites are acquiring a market sector of conventional as well as thermoset composites. However, replacing the thermoset with a thermoplastic composite has never been an easy task. The inherent high viscosity of thermoplastic resin reveals poor interface properties. In this work, a homo-polymer towpreg is produced through an electrostatic powder spray coating methodology. The produced flexible towpreg offers a low melt-flow distance during the consolidation of the laminate. The reduced melt-flow distance demonstrates a homogeneous fibre/matrix distribution (and low void content) on consolidation. The composite laminate has been fabricated with two manufacturing techniques such as conventional film stack (FS) and powder-coated (PC) technique. This helps in understanding the distinct response of produced laminates on applying load since the laminates produced through the two techniques are comprised of the same constituent fibre and matrix (constant fibre volume fraction). The changed behaviour is observed mainly due to the different fibre/matrix configurations within the laminate. The interface adhesion influences the load transfer between the fibre and matrix. Therefore, it influences the elastic, plastic, and failure patterns of the laminates. Moreover, the effect of preform geometries (plain weave and satin weave structure) are also studied for corresponding composite laminates in terms of various mechanical properties. The fracture analysis is carried out to study the effect of resin at the interlacement points through micro-CT analysis. The PC laminate reveals a considerably small matrix-rich and deficient zone in comparison to the FS laminate. The different load tensile, shear, fracture toughness, and drop weight impact test) is applied to the laminates, and corresponding damage behaviour is analysed in the successive stage of failure. The PC composite has shown superior mechanical properties in comparison to the FS composite. The damage that occurs in the laminate is captured through the SEM analysis to identify the prominent mode of failure, such as matrix cracking, fibre breakage, delamination, debonding, and other phenomena.

Keywords: composite, damage, fibre, manufacturing

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Authors: S. Lecheb, A. Nour, A. Chellil, H. Mechakra, N. Tchina, H. Kebir

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This study concerned the dynamic behavior of the wind turbine rotor. Before all, we have studied the loads applied to the rotor, which allows the knowledge their effect on the fatigue. We also studied the movement of the longitudinal cracked rotor in order to determine stress, strain and displacement. Moreover, to study the issues of cracks in the critical zone ABAQUS software is used, which based to the finite element to give the results. In the first we compared the first six modes shapes between cracking and uncracking of HAWT rotor. In the second part, we show the evolution of six first naturals frequencies with longitudinal crack propagation. Finally, we conclude that the residual change in the naturals frequencies can be used as in shaft crack diagnosis predictive maintenance.

Keywords: wind turbine rotor, natural frequencies, longitudinal crack growth, life time

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Authors: Mahmoud Mohamed Emam, Yasser Fathy Hendawy Al-Mahdy

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Higher education institutions (HEIs) in Arab countries have witnessed large scope transformations as a result of embracing globalised practices. The introduction of program academic accreditation in HEIs in the Arab context has been regarded as a change enterprise that has proponents and opponents. In essence, introducing new systems or practices trigger changes that may shatter employees at a given organization. Therefore, it is argued that the interaction between organizational, contextual, and individual-related variables are likely to determine how the organization succeeds in facing resistance to change. This study investigated a mediated-effects model of organizational support and citizenship behavior. The model proposes organizational support as an antecedent of citizenship behavior and commitment to change as a mediator in the organizational support–citizenship behavior relationship. Survey data were collected and analyzed from university faculty (n=221) using structural equation modeling. Findings showed that organizational support significantly contributes to increasedcitizenshipbehaviour and the commitment of university faculty to program accreditation as a change enterprise, which has a significant and direct impact on their citizenship behaviour. We conclude that university-level organizational support shapes faculty’s commitment to change both directly and indirectly. The findings have significant practical implications for HEIs in Arab countries when they introduce new practices that aim at improving institutional effectiveness.

Keywords: organizational support, accreditation, commitment, citizenship behaviour

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Authors: M. Boumaiza, S. Mohamadi, B. Moussai

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In this article the study of the seismic response of an earth dam with sealing walls has been made by introducing the effect of the change of position and depth of the sealing wall and the effect of non-linear behavior of soil of the foundation by taking into account the variation of the viscous damping and shear modulus in each layer of soil on the seismic response of the dam. As a case study, we take the Algerian dam Kef-Eddir which lies in the far west of the territory of the Wilaya of Tipaza (wadi Eddamous), classified according to the RPA 2003 as a high seismicity zone (zone III). With a height of 71m above the foundation and a width of 478m. The seismic event applied to the rock, is the earthquake of Chenoua (29 October, 1989), with a magnitude Mw=6 that hit the region.

Keywords: earth dam, earthquake, sealing walls, viscous damping

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Authors: E. Zippelius

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Urban design aims to provide a stage for public life that, when once brought to life, is right away subject to subtle but continuous transformation. This paper explores such transformations and searches for ways how public life can be reinforced in the case of a housing settlement for the displaced in Nicosia, Cyprus. First, a sound basis of theoretical knowledge is established through literature review, notably the theory of the Production of Space by Henri Lefebvre, exploring its potential and defining key criteria for the following empirical analysis. The analysis is pinpointing the differences between spatial practice, representation of space and spaces of representation as well as their interaction, alliance, or even conflict. In doing so uncertainties, chances and challenges are unraveled that will be consequently linked to practice and action and lead to the formulation of a design strategy. A strategy, though, that does not long for achieving an absolute, finite certainty but understands the three dimensions of space formulated by Lefebvre as equal and space as continuously produced, hence, unfinished.

Keywords: production of space, public space, urban life, urban transformation

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Authors: Irene H. Maralit

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Warning labels have been found to inform smokers about the health hazards of smoking, encourage smokers to quit, and prevent nonsmokers from starting to smoke. Warning labels on tobacco products are an ideal way of communicating with smokers. Since the intervention is delivered at the time of smoking, nearly all smokers are exposed to warning labels and pack-a-day smokers could be exposed to the warnings more than 7,000 times per year. Given the reach and frequency of exposure, the proponents want to know the effect of warning labels on smoking behavior. Its aims to identify the profile of the smokers associated with its behavioral variables that best describe the users’ perception. The behavioral variables are AVOID, THINK RISK and FORGO. This research study aims to determine if there is significant relationship between the effect of warning labels on cigarette package on Consumer behavior when grouped according to profile variable. The researcher used quota sampling to gather representative data through purposive means to determine the accurate representation of data needed in the study. Furthermore, the data was gathered through the use of a self-constructed questionnaire. The statistical method used were Frequency count, Chi square, multi regression, weighted mean and ANOVA to determine the scale and percentage of the three variables. After the analysis of data, results shows that most of the respondents belongs to age range 22–28 years old with percentage of 25.3%, majority are male with a total number of 134 with percentage of 89.3% and single with total number of 79 and percentage of 52.7%, mostly are high school graduates with total number of 59 and percentage of 39.3, with regards to occupation, skilled workers have the highest frequency of 37 with 24.7%, Majority of the income of the respondents falls under the range of Php 5,001-Php10,000 with 50.7%. And also with regards to the number of sticks consumed per day falls under 6–10 got the highest frequency with 33.3%. The respondents THINK RISK factor got the highest composite mean which is 2.79 with verbal interpretation of agree. It is followed by FORGO with 2.78 composite mean and a verbal interpretation of agree and AVOID variable with composite mean of 2.77 with agree as its verbal interpretation. In terms of significant relationship on the effects of cigarette label to consumer behavior when grouped according to profile variable, sex and occupation found to be significant.

Keywords: consumer behavior, smokers, warning labels, think risk avoid forgo

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Authors: Ashkan Zargar, Ali Taheri Mirghaed, Zein Talal Barakat, Alireza Khosravi, Hamed Paknejad

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With the increase of bacterial resistance to the chemical antibiotics, replacing it with ecofriendly herbal materials and with no adverse effects in the host body is very important. Therefore, in this study, the effect of combined essential oil (Thymus vulgaris-Origanum magorana and Ziziphora clinopodioides) on the growth behavior of Yersinia ruckeri, Aeromonas hydrophila and Lactococcus garvieae was evaluated. The compositions of the herbal essential oils used in this study were determined by gas chromatography-mass spectrometry (GC-MS) while, the investigating of antimicrobial effects was conducted by the agar-disc diffusion method, determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and bacterial growth curves determination relied on optical density (OD) at 630 nm. The main compounds were thymol (40.60 %) and limonene (15.98 %) for Thymus vulgaris while carvacrol (57.86 %) and thymol (13.54 %) were the major compounds in Origanum magorana. As regards Ziziphora clinopodiodes, α-pinene (22.6 %) and carvacrol (21.1 %) represented the major constituents. Concerning Yersinia ruckeri, disc-diffusion results showed that t.O.z (50 % Origanum majorana) combined essential oil was presented the best inhibition zone (30.66 mm) but it was exhibited no significant differences with other tested commercial antibiotics except oxytetracycline (P <0/05). The inhibitory activity and the bactericidal effect of the t.O.z, unveiled by the MIC= 0.2 μL /mL and MBC= 1.6 μL /mL values, were clearly the best between all combined oils. The growth behaviour of Yersinia ruckeri was affected by this combined essential oil and changes in temperature and pH conditions affected herbal oil performance. As regard Aeromonas hydrophila, its results were so similar to Yersinia ruckeri results and t.O.z (50 % Origanum majorana) was the best between all combined oils (inhibition zone= 26 mm, MIC= 0.4 μL /mL and MBC= 3.2 μL /mL, combined essential oil was affected bacterial growth behavior). Also for Lactococcus garvieae, t.O.z (50 % Origanum majorana) was the best between all combined oils having the best inhibition zone= 20.66 mm, MIC= 0.8 μL /mL and MBC= 1.6 μL /mL and best effect on inhibiting bacterial growth. Combined herbal essential oils have a good and noticeable effect on the growth behavior of pathogenic bacteria in the laboratory, and by continuing research in the host, they may be a suitable alternative to control, prevent and treat diseases caused by these bacteria.

Keywords: bacterial pathogen, herbal medicine, growth behavior, fish

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Authors: Mitsuyoshi Tomiya, Kentaro Kawamura, Shoichi Sakamoto

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In chaotic billiard systems, scar-like localization has been found on time-evolving wave packet. We may call it the “dynamical scar” to separate it to the original scar in stationary states. It also comes out along the vicinity of classical unstable periodic orbits, when the wave packets are launched along the orbits, against the hypothesis that the waves become homogenous all around the billiard. Then time-evolving wave packets are investigated numerically in phase space. The Wigner function is adopted to detect the wave packets in phase space. The 2-dimensional Poincaré sections of the 4-dimensional phase space are introduced to clarify the dynamical behavior of the wave packets. The Poincaré sections of the coordinate (x or y) and the momentum (Px or Py) can visualize the dynamical behavior of the wave packets, including the behavior in the momentum degree also. For example, in “dynamical scar” states, a bit larger momentum component comes first, and then the a bit smaller and smaller components follow next. The sections made in the momentum space (Px or Py) elucidates specific trajectories that have larger contribution to the “dynamical scar” states. It is the fixed point observation of the momentum degrees at a specific fixed point(x0, y0) in the phase space. The accumulation are also calculated to search the “dynamical scar” in the Poincare sections. It is found the scars as bright spots in momentum degrees of the phase space.

Keywords: chaotic billiard, Poincaré section, scar, wave packet

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Authors: M. A. Islam, P. J. Hazell, J. P. Escobedo, M. Saadatfar

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Quasistatic compression and micro structural characterization of closed cell aluminium foams of different pore size and cell distributions has been carried out. Metallic foams have good potential for lightweight structures for impact and blast mitigation and therefore it is important to find out the optimized foam structure (i.e. cell size, shape, relative density, and distribution) to maximize energy absorption. In this paper, we present results for two different aluminium metal foams of density 0.5 g/cc and 0.7 g/cc respectively that have been tested in quasi-static compression. The influence of cell geometry and cell topology on quasistatic compression behavior has been investigated using computed tomography (micro-CT) analysis. The compression behavior and micro structural characterization will be presented.

Keywords: metal foams, micro-CT, cell topology, quasistatic compression

Procedia PDF Downloads 439

Authors: Wan-Ting Liao, Angela K. Tzeng

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Empathy has been an important issue in psychology, education, as well as cognitive neuroscience. Empathy has two major components: cognitive and emotional. Cognitive component refers to the ability to understand others’ perspectives, thoughts, and actions, whereas emotional component refers to understand how others feel. Empathy can be induced, attitude can then be changed, and with enough attitude change, helping behavior can occur. This finding leads us to two questions: is attitude change really necessary for prosocial behavior? And, what roles cognitive and affective empathy play? For the second question, participants with different psychopathic personality (PP) traits are critical because high PP people were found to suffer only affective empathy deficit. Their cognitive empathy shows no significant difference from the control group. 132 college students voluntarily participated in the current three-stage study. Stage 1 was to collect basic information including Interpersonal Reactivity Index (IRI), Psychopathic Personality Inventory-Revised (PPI-R), Attitude Scale, Visual Analogue Scale (VAS), and demographic data. Stage two was for empathy induction with three controversial scenarios, namely domestic violence, depression with a suicide attempt, and an ex-offender. Participants read all three stories and then rewrite the stories by one of two perspectives (empathetic vs. objective). They would then complete the VAS and Attitude Scale one more time for their post-attitude and emotional status. Three IVs were introduced for data analysis: PP (High vs. Low), Responsibility (whether or not the character is responsible for what happened), and Perspective-taking (Empathic vs. Objective). Stage 3 was for the action. Participants were instructed to freely use the 17 tokens they received as donations. They were debriefed and interviewed at the end of the experiment. The major findings were people with higher empathy tend to take more action in helping. Attitude change is not necessary for prosocial behavior. The controversy of the scenarios and how familiar participants are towards target groups play very important roles. Finally, people with high PP tend to show more public prosocial behavior due to their affective empathy deficit. Pre-existing value and belief as well as recent dramatic social events seem to have a big impact and possibly reduce the effect of the independent variables (IV) in our paradigm.

Keywords: empathy, cognitive, emotional, psychopathy

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Authors: S. A. Agbalajobi, W. A. Bello

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This study examines rock properties of crushed aggregate in some selected quarries in Kwara state, Nigeria. Some physical properties (chemical composition, mineral composition, particle size distribution) of gneiss sample were determined using ISRM standards. The physicomechanical properties (specific gravity, dry density, porosity, water absorption, point load index, tensile, and compressive strength) of the gneiss rock were evaluated. The analysis on the gneiss samples revealed the mean dry density and the unit weight are 2.52 g/m3, 2.63 g/m3, 2.38 g/m3; and 24.1 kN/m3, 25.78 kN/m3, 23.33 kN/m3, respectively (for locations A,B,C). The water absorption level of the gneiss rock sample ranged from 0.38 % – 0.57 % for the three locations. The mean Schmidt hammer rebound value ranged from 51.0 – 52.4 for the three locations and mean point load index values ranged from 9.89 – 10.56 MPa classified as very high strength while the uniaxial compressive strength of the rock samples revealed that its strength ranged from 120 - 139 MPa (for location A, B, and C) classified as strong rock. The aggregate impact value test and aggregate crushing value test conducted on the gneiss aggregates from the three locations in accordance with British Standard. The gneiss sample from the three locations (A, B, and C) is a good material for the production of construction works such as concrete, bricks, pavement, embankment among others, the compressive strength of the material is within the accepted limit.

Keywords: gneiss, aggregate impact, aggregate crushing, physic-mechanical properties, rock hardness

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Authors: Salah Hamri, Tewfik Bouchaour, Ulrich Maschke

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The aim of this works is the study of swelling ratio of cross-linked polymer networks poly (2-hydroxyethyl methacrylate) (PHEMA). The system composed of erythrosine and Triethanolamine, in aqueous medium, is used as photo-initiator and 1,6-Hexanediol diacrylate as cross-linker. The analysis of UV-visible and infrared spectra, which were taken at different times during polymerization/cross linking, makes it possible to obtain useful information on the reaction mechanism. The swelling behavior was study by changing the nature of solvent, dye sensitizer (erythrosine, rose Bengal and eosin), and pH of the medium. The exploitation of experimental results using Fick diffusion model is also expected and shows a good correlation between theoretical and experimental results.

Keywords: cross-linker, photo-sensitizer, polymer network, swelling ratio

Procedia PDF Downloads 297