Search results for: positive behavior recognition
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14236

Search results for: positive behavior recognition

12196 Mechanical Characterization of Porcine Skin with the Finite Element Method Based Inverse Optimization Approach

Authors: Djamel Remache, Serge Dos Santos, Michael Cliez, Michel Gratton, Patrick Chabrand, Jean-Marie Rossi, Jean-Louis Milan

Abstract:

Skin tissue is an inhomogeneous and anisotropic material. Uniaxial tensile testing is one of the primary testing techniques for the mechanical characterization of skin at large scales. In order to predict the mechanical behavior of materials, the direct or inverse analytical approaches are often used. However, in case of an inhomogeneous and anisotropic material as skin tissue, analytical approaches are not able to provide solutions. The numerical simulation is thus necessary. In this work, the uniaxial tensile test and the FEM (finite element method) based inverse method were used to identify the anisotropic mechanical properties of porcine skin tissue. The uniaxial tensile experiments were performed using Instron 8800 tensile machine®. The uniaxial tensile test was simulated with FEM, and then the inverse optimization approach (or the inverse calibration) was used for the identification of mechanical properties of the samples. Experimentally results were compared to finite element solutions. The results showed that the finite element model predictions of the mechanical behavior of the tested skin samples were well correlated with experimental results.

Keywords: mechanical skin tissue behavior, uniaxial tensile test, finite element analysis, inverse optimization approach

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12195 Modeling of Bioelectric Activity of Nerve Cells Using Bond Graph Method

Authors: M. Ghasemi, F. Eskandari, B. Hamzehei, A. R. Arshi

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Bioelectric activity of nervous cells might be changed causing by various factors. This alteration can lead to unforeseen circumstances in other organs of the body. Therefore, the purpose of this study was to model a single neuron and its behavior under an initial stimulation. This study was developed based on cable theory by means of the Bond Graph method. The numerical values of the parameters were derived from empirical studies of cellular electrophysiology experiments. Initial excitation was applied through square current functions, and the resulted action potential was estimated along the neuron. The results revealed that the model was developed in this research adapted with the results of experimental studies and demonstrated the electrical behavior of nervous cells properly.

Keywords: bond graph, stimulation, nervous cells, modeling

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12194 Numerical Simulation and Experimental Validation of the Hydraulic L-Shaped Check Ball Behavior

Authors: Shinji Kajiwara

Abstract:

The spring-driven ball-type check valve is one of the most important components of hydraulic systems: it controls the position of the ball and prevents backward flow. To simplify the structure, the spring must be eliminated, and to accomplish this, the flow pattern and the behavior of the check ball in L-shaped pipe must be determined. In this paper, we present a full-scale model of a check ball made of acrylic resin, and we determine the relationship between the initial position of the ball, the position and diameter of the inflow port. The check flow rate increases in a standard center inflow model, and it is possible to greatly decrease the check-flow rate by shifting the inflow from the center.

Keywords: hydraulics, pipe flow, numerical simulation, flow visualization, check ball, L-shaped pipe

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12193 Behavior of Laterally Loaded Multi-Helix Helical Piles Under Vertical Loading in Cohesive and Cohesionless Soils

Authors: Mona Fawzy Aldaghma

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Helical piles are gaining popularity as a viable deep foundation alternative due to their quick installation and multipurpose use in compression and tension. These piles are commonly used as foundations for constructions such as solar panels, wind turbines and offshore platforms. These structures typically transfer various combinations of loads to their helical-pile foundations, including axial and lateral loads. Further research is needed to determine the effects of loading patterns that may act on helical piles as compounds of axial compression and lateral stresses. Multi helical piles are used to increase the efficiency of these piles. In this study, it investigate the behavior of laterally loaded helical piles with multiple helices when subjected to vertical loading conditions in both cohesive and cohesionless soils. Two models of intermediate shaft rigidity are studied with either two or three helices. Additionally, the vertical loading conditions were altered between successive and simultaneous loading. The cohesionless soil is sand with medium density and the cohesive soil is clay with medium cohesion. The study will carried out with numerical analysis using PLAXIS 3D and will be verified by an experimental tests. The numerical simulations reveal that helical piles exhibit different behavior in cohesive soil compared to cohesionless soil.

Keywords: helical piles, multi-helix, numerical modeling, PLAXIS 3D, cohesive soil, cohesionless soil, experimental

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12192 Hepatitis B Prevalence in Institutionalized Intellectually Disabled Children

Authors: Maryam Vaezjalali, Foad Davoodbeglou, Mehrnaz Mesdaghi, Hossein Goudarzi, Fariba Shojaei, Hourieh Aram

Abstract:

Introduction: Hepatitis B virus (HBV) infection causes chronic infection in human population, with high mortality. Some people are more susceptible to this infection. One of the high risk communities is mentally retarded children, who are institutionalized. Special conditions in these centers predispose children for HBV infection and transmission to healthy people. In this study our objective was to determine the prevalence of HBV infection among institutionalized mentally retarded children and study its associated risk factors. Materials and methods: In this study, 250 mentally retarded children (younger than 14 years old) were included. They were living in 5 nursing institutions, located in different parts of Tehran. HBsAg was measured in the sera of these patients by ELISA method. Results: Among 250 children, 20 children (8%) were HBsAg positive. HBV infection in girls was more than boys (11% to 5.6%). Among the types of mental retardation, children with cerebral palsy had the highest positive result for HBsAg. The most HBV infection (28.5%) was seen in children with longest duration of being institutionalized (10 to 11 years). Vaccinated children were more HBsAg positive (8.7%) than non-vaccinated children (5.3%). However, no significant relationship was observed between any of these factors and HBsAg positivity. Conclusion: Despite improvement of people’s health condition and implementation of HBV vaccination, the prevalence of HBV infection is high in institutionalized mentally retarded children, which highlights the need for active measures to reduce this infection among this high risk population.

Keywords: hepatitis B virus, HBV vaccine, intellectually disabled children, mentally retarded

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12191 Experimental and Computational Analysis of Glass Fiber Reinforced Plastic Beams with Piezoelectric Fibers

Authors: Selin Kunc, Srinivas Koushik Gundimeda, John A. Gallagher, Roselita Fragoudakis

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This study investigates the behavior of Glass Fiber Reinforced Plastic (GFRP) laminated beams additionally reinforced with piezoelectric fibers. The electromechanical behavior of piezoelectric materials coupled with high strength/low weight GFRP laminated beams can have significant application in a wide range of industries. Energy scavenging through mechanical vibrations is the focus of this study, and possible applications can be seen in the automotive industry. This study examines the behavior of such composite laminates using Classical Lamination Theory (CLT) under three-point bending conditions. Fiber orientation is optimized for the desired stiffness and deflection that yield maximum energy output. Finite element models using ABAQUS/CAE are verified through experimental testing. The optimum stacking sequences examined are [0o]s, [ 0/45o]s, and [45/-45o]s. Results show the superiority of the stacking sequence [0/45o]s, providing higher strength at a lower weight, and maximum energy output. Furthermore, laminated GFRP beams additionally reinforced with piezoelectric fibers can be used under bending to not only replace metallic component while providing similar strength at a lower weight but also provide an energy output.

Keywords: classical lamination theory (CLT), energy scavenging, glass fiber reinforced plastics (GFRP), piezoelectric fibers

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12190 Influence of Annealing on the Mechanical αc-Relaxation of Isotactic-Polypropylene: A Study from the Intermediate Phase Perspective

Authors: Baobao Chang, Konrad Schneider, Vogel Roland, Gert Heinrich

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In this work, the influence of annealing on the mechanical αc-relaxation behavior of isotactic polypropylene (iPP) was investigated. The results suggest that the mechanical αc-relaxation behavior depends strongly on the confinement force on the polymer chains in the intermediate phase and the thickness of the intermediate phase. After quenching at 10°C, abundant crystallites with a wide size distribution are formed. The polymer chains in the intermediate phase are constrained by the crystallites, giving rise to one broad αc-relaxation peak. With an annealing temperature between 60°C~105°C, imperfect lamellae melting releases part of the constraint force, which reduces the conformational ordering of the polymer chains neighboring the amorphous phase. Consequently, two separate αc-relaxation peaks could be observed which are labeled as αc1-relaxation and αc2-relaxation. αc1-relaxation and αc2-relaxation describe the relaxation behavior of polymer chains in the region close to the amorphous phase and the crystalline phase, respectively. Both relaxation peaks shift to a higher temperature as annealing temperature increases. With an annealing temperature higher than 105°C, the new crystalline phase is formed in the intermediate phase, which enhances the constraint force on the polymer chains. αc1-relaxation peak is broadened obviously and its position shifts to a higher temperature as annealing temperature increases. Moreover, αc2-relaxation is undetectable because that the polymer chains in the region between the initial crystalline phase and the newly formed crystalline phase are strongly confined.

Keywords: annealing, αc-relaxation, isotactic-polypropylene, intermediate phase

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12189 Effect of Austenitization Temperature on Wear Behavior of Carbidic Austempered Ductile Iron (CADI)

Authors: Ajay Likhite, Prashant Parhad, D. R. Peshwe, S. U. Pathak

Abstract:

Chromium bearing Austempered Ductile Iron (ADI) has been recently in the news for its improved wear performance over the ADI. The work presented below was taken up to study the effect of different austenitisation temperatures on the microstructure and wear performance of the Carbidic Austempered Ductile Iron (CADI). In this investigation Cr bearing ductile iron was subjected to austempering treatment to obtain an ausferritic microstructure. Two different austenitisation temperatures were selected whereas, the austempering temperature and time was kept unchanged. Microstructure and wear performance of this alloy, austenitized at two different temperatures was studied.

Keywords: austempered ductile iron, carbidic austempered ductile iron, austenitization temperature, wear behavior

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12188 Cognitive Function and Coping Behavior in the Elderly: A Population-Based Cross-Sectional Study

Authors: Ryo Shikimoto, Hidehito Niimura, Hisashi Kida, Kota Suzuki, Yukiko Miyasaka, Masaru Mimura

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Introduction: In Japan, the most aged country in the world, it is important to explore predictive factors of cognitive function among the elderly. Coping behavior relieves chronic stress and improves lifestyle, and consequently may reduce the risk of cognitive impairment. One of the most widely investigated frameworks evaluated in previous studies is approach-oriented and avoidance-oriented coping strategies. The purpose of this study is to investigate the relationship between cognitive function and coping strategies among elderly residents in urban areas of Japan. Method: This is a part of the cross-sectional Arakawa geriatric cohort study for 1,099 residents (aged 65 to 86 years; mean [SD] = 72.9 [5.2]). Participants were assessed for cognitive function using the Mini-Mental State Examination (MMSE) and diagnosed by psychiatrists in face-to-face interviews. They were then investigated for their each coping behaviors and coping strategies (approach- and avoidance-oriented coping) using stress and coping inventory. A multiple regression analysis was used to investigate the relationship between MMSE score and each coping strategy. Results: Of the 1,099 patients, the mean MMSE score of the study participants was 27.2 (SD = 2.7), and the numbers of the diagnosis of normal, mild cognitive impairment (MCI), and dementia were 815 (74.2%), 248 (22.6%), and 14 (1.3%), respectively. Approach-oriented coping score was significantly associated with MMSE score (B [partial regression coefficient] = 0.12, 95% confidence interval = 0.05 to 0.19) after adjusting for confounding factors including age, sex, and education. Avoidance-oriented coping did not show a significant association with MMSE score (B [partial regression coefficient] = -0.02, 95% confidence interval = -0.09 to 0.06). Conclusion: Approach-oriented coping was clearly associated with neurocognitive function in the Japanese population. A future longitudinal trial is warranted to investigate the protective effects of coping behavior on cognitive function.

Keywords: approach-oriented coping, cognitive impairment, coping behavior, dementia

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12187 Biostimulation and Muscular Ergogenic Effect of Ozone Therapy on Buttock Augmentation: A Case Report and Literature Review

Authors: Ferreira R., Rocha K.

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Ozone therapy is indicated for improving skin aesthetics, bio-stimulating and ergogenic effect. This paper aims to carry out a case report that demonstrates the positive results of ozone therapy in buttock augmentation. The application showed positive results for skin bio stimulating, neocollagenesis, adipogenesis, and ergogenic muscle effect in the reported case, demonstrating to be a viable clinical technique. Buttock augmentation with ozone therapy is a promising aesthetic therapeutic modality with fast and safe results as an aesthetic therapeutic option for buttock augmentation.

Keywords: bio-stimulating effect, ozone therapy, muscular ergogenic, buttock augmentation

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12186 (De)Motivating Mitigation Behavior: An Exploratory Framing Study Applied to Sustainable Food Consumption

Authors: Youval Aberman, Jason E. Plaks

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This research provides initial evidence that self-efficacy of mitigation behavior – the belief that one’s action can make a difference on the environment – can be implicitly inferred from the way numerical information is presented in environmental messages. The scientific community sees climate change as a pressing issue, but the general public tends to construe climate change as an abstract phenomenon that is psychologically distant. As such, a main barrier to pro-environmental behavior is that individuals often believe that their own behavior makes little to no difference on the environment. When it comes to communicating how the behavior of billions of individuals affects global climate change, it might appear valuable to aggregate those billions and present the shocking enormity of the resources individuals consume. This research provides initial evidence that, in fact, this strategy is ineffective; presenting large-scale aggregate data dilutes the contribution of the individual and impedes individuals’ motivation to act pro-environmentally. The high-impact, underrepresented behavior of eating a sustainable diet was chosen for the present studies. US Participants (total N = 668) were recruited online for a study on ‘meat and the environment’ and received information about some of resources used in meat production – water, CO2e, and feed – with numerical information that varied in its frame of reference. A ‘Nation’ frame of reference discussed the resources used in the beef industry, such as the billions of CO2e released daily by the industry, while a ‘Meal’ frame of reference presented the resources used in the production of a single beef dish. Participants completed measures of pro-environmental attitudes and behavioral intentions, either immediately (Study 1) or two days (Study 2) after reading the information. In Study 2 (n = 520) participants also indicated whether they consumed less or more meat than usual. Study 2 included an additional control condition that contained no environmental data. In Study 1, participants who read about meat production at a national level, compared to at a meal level, reported lower motivation to make ecologically conscious dietary choices and reported lower behavioral intention to change their diet. In Study 2, a similar pattern emerged, with the added insight that the Nation condition, but not the Meal condition, deviated from the control condition. Participants across conditions, on average, reduced their meat consumption in the duration of Study 2, except those in the Nation condition who remained unchanged. Presenting nation-wide consequences of human behavior is a double-edged sword: Framing in a large scale might reveal the relationship between collective actions and environmental issues, but it hinders the belief that individual actions make a difference.

Keywords: climate change communication, environmental concern, meat consumption, motivation

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12185 Negation of Insinuation Rule on the Ideas of Imam Khomeini (RA)

Authors: Seyed Jafar Hosseini, Rahim Vakilzadeh, Hassan Movassagi

Abstract:

‘Negation of insinuation’ or ‘negation of dominance’ Rule is considered as one of the most important principles governing the policies and external relations of Islamic and religious countries. The stable and influential role which this rule puts on the behavior and policies of the Islamic religion and foreign policies of Islamic countries shows the importance of the presented topic. Among Islamic scholars, Imam Khomeini (RA) has been paid most attention to this rule on governing issues. In the present study, we are going to investigate the nature and dimensions of Negation of insinuation rule in Imam Khomeini's ideas with an analytical and descriptive method. The obtained results show that Negation of insinuation rule is an effective and main guidance in Imam's thoughts and behavior.

Keywords: negation of insinuation Rule, Imam Khomeini (RA), cultural domination, political domination, economic domination

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12184 Stability of Pump Station Cavern in Chagrin Shale with Time

Authors: Mohammad Moridzadeh, Mohammad Djavid, Barry Doyle

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An assessment of the long-term stability of a cavern in Chagrin shale excavated by the sequential excavation method was performed during and after construction. During the excavation of the cavern, deformations of rock mass were measured at the surface of excavation and within the rock mass by surface and deep measurement instruments. Rock deformations were measured during construction which appeared to result from the as-built excavation sequence that had potentially disturbed the rock and its behavior. Also some additional time dependent rock deformations were observed during and post excavation. Several opinions have been expressed to explain this time dependent deformation including stress changes induced by excavation, strain softening (or creep) in the beddings with and without clay and creep of the shaley rock under compressive stresses. In order to analyze and replicate rock behavior observed during excavation, including current and post excavation elastic, plastic, and time dependent deformation, Finite Element Analysis (FEA) was performed. The analysis was also intended to estimate long term deformation of the rock mass around the excavation. Rock mass behavior including time dependent deformation was measured by means of rock surface convergence points, MPBXs, extended creep testing on the long anchors, and load history data from load cells attached to several long anchors. Direct creep testing of Chagrin Shale was performed on core samples from the wall of the Pump Room. Results of these measurements were used to calibrate the FEA of the excavation. These analyses incorporate time dependent constitutive modeling for the rock to evaluate the potential long term movement in the roof, walls, and invert of the cavern. The modeling was performed due to the concerns regarding the unanticipated behavior of the rock mass as well as the forecast of long term deformation and stability of rock around the excavation.

Keywords: Cavern, Chagrin shale, creep, finite element.

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12183 Numerical Study of Flow Characteristics and Performance of 14-X B Inlet with Blunted Cowl-Lip

Authors: Sergio N. P. Laitón, Paulo G. P. Toro, João F. Martos

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A numerical study has been carried out to investigate the flow characteristics and performance of the 14-X B inlet with blunted cowl-lip. The Brazilian aerospace hypersonic vehicle 14-X B is a technology demonstrator of a hypersonic air-breathing propulsion system, based on supersonic combustion ramjet (scramjet). It is designed for Earth's atmospheric flight at Mach number of 6 and an altitude of 30 km. Currently, it is under development in the aerothermodynamics and hypersonic Professor Henry T. Nagamatsu laboratory at Advanced Studies Institute (IEAv). Numerical simulations were conducted at nominal freestream Mach number and altitude for two cowl-lip blunting radius and several angles of attack close to horizontal flight. The results show that the shock interference behavior on the blunted cowl-lip change with the angle of attack and blunted radius. The type VI or V together with III shock interferences are more likely to occur simultaneously at small negative angles of attack. When the inlet operates in positive angles of attack higher to 1, no shock interference occurs, only the bow shock conditions. The results indicate a high air pressure at beginning of the combustor and higher pressure recovery with 2 mm radius and positives angles of attack.

Keywords: blunted cowl-lip, hypersonic inlet, inlet unstart, shock interference

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12182 The Influence of Destination Image on Tourists' Experience at Osun Osogbo World Heritage Site

Authors: Bola Adeleke, Kayode Ogunsusi

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Heritage sites have evolved to preserve culture and heritage and also to educate and entertain tourists. Tourist travel decisions and behavior are influenced by destination image and value of the experience of tourists. Perceived value is one of the important tools for securing a competitive edge in tourism destinations. The model of Ritchie and Crouch distinguished 36 attributes of competitiveness which are classified into five factors which are quality of experience, touristic attractiveness, environment and infrastructure, entertainment/outdoor activities and cultural traditions. The study extended this model with a different grouping of the determinants of destination competitiveness. The theoretical framework used for this study assumes that apart from attractions already situated in the grove, satisfaction with destination common service, and entertainment and events, can all be used in creating a positive image for/and in attracting customers (destination selection) to visit Osun Sacred Osogbo Grove during and after annual celebrations. All these will impact positively on travel experience of customers as well as their spiritual fulfillment. Destination image has a direct impact on tourists’ satisfaction which consequently impacts on tourists’ likely future behavior on whether to revisit a cultural destination or not. The study investigated the variables responsible for destination image competitiveness of the Heritage Site; assessed the factors enhancing the destination image; and evaluated the perceived value realized by tourists from their cultural experience at the grove. A complete enumeration of tourists above 18 years of age who visited the Heritage Site within the month of March and April 2017 was taken. 240 respondents, therefore, were used for the study. The structured questionnaire with 5 Likert scales was administered. Five factors comprising 63 variables were used to determine the destination image competitiveness through principal component analysis, while multiple regressions were used to evaluate perceived value of tourists at the grove. Results revealed that 11 out of the 12 variables determining the destination image competitiveness were significant in attracting tourists to the grove. From the R-value, all factors predicted tourists’ value of experience strongly (R= 0.936). The percentage variance of customer value was explained by 87.70% of the variance of destination common service, entertainment and event satisfaction, travel environment satisfaction and spiritual satisfaction, with F-value being significant at 0.00. Factors with high alpha value contributed greatly to adding value to enhancing destination and tourists’ experience. 11 variables positively predicted tourist value with significance. Managers of Osun World Heritage Site should improve on variables critical to adding values to tourists’ experience.

Keywords: competitiveness, destination image, Osun Osogbo world heritage site, tourists

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12181 An Examination of Thai Tourists' Motivation Behavior and Perception of Cultural Heritage in Chiang Mai Province

Authors: Sujui Yang, Peeraya Somsak, Markus Blut

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This research examines the international tourists in Chiang Mai, Thailand. It aims to study non-Thai tourists’ of this region to better understand their behavior and motives influencing the choice of cultural heritage tourists in Chiang Mai, Thailand. The data includes questionnaires of 250 tourists in the study area. The most important motives influencing decisions choices are several concerning customers’ perspectives on tourist destinations in cultural heritage in Chiang Mai province. Thai tourists in Chiang Mai are single, 72.5 percent are in the age of 21-40 years old and 50% of sample group are from central and northern of Thailand. Tourists’ motives capture the factor loading as well as the corresponding show 5 components: relaxation motives, place/ physical motives, learning motives, image motives, and achievement motives.

Keywords: tourists motives, cultural heritage, Chiang Mai, customers’ perspectives

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12180 Dissimilar Cu/Al Friction Stir Welding: Sensitivity of the Tool Offset

Authors: Tran Hung Tra, Hao Dinh Duong, Masakazu Okazaki

Abstract:

Copper 1100 and aluminum 1050 plates with a thickness of 5.0 mm are butt-joint using friction stir welding. The tool offset is linearly varied along the welding path. Two welding regimes, using the same linear tool offset but in opposite directions, are applied for fabricating two Cu/Al plates. The material flow is dominated by both tool offset and offset history. The intermetallic compounds layer and interface morphology in each welded plate are formed in a different manner. As a result, the bonding strength and fracture behavior between two welded plates are significantly distinct. The role of interface morphology on fracture behavior is analyzed by the finite element method.

Keywords: Cu/Al dissimilar welding, offset history, interface morphology, intermetallic compounds, strength and fracture

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12179 Growth of New Media Advertising

Authors: Palwinder Bhatia

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As all know new media is a broad term in media studies that emerged in the latter part of the 20th century which refers to on-demand access to content any time, anywhere, on any digital device, as well as interactive user feedback, creative participation and community formation around the media content. The role of new media in advertisement is impeccable these days. It becomes the cheap and best way of advertising. Another important promise of new media is the democratization of the creation, publishing, distribution and consumption of media content. New media brings a revolution in about every field. It makes bridge between customer and companies. World make a global village with the only help of new media. Advertising helps in shaping the consumer behavior and effect on consumer psychology, sociology, social anthropology and economics. People do comments and like the particular brands on the networking sites which create mesmerism impact on the behavior of customer. Recent study did by Times of India shows that 64% of Facebook users have liked a brand on Facebook.

Keywords: film, visual, culture, media, advertisement

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12178 The Friction and Wear Behavior of 0.35 VfTiC-Ti3SiC2 Composite

Authors: M. Hadji, A. Haddad, Y. Hadji

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The effects of boronizing treatment on the friction coefficient and wear behavior of 0.35 Vf TiC- Ti3 SiC2 composite were investigated. In order to modify the surface properties of Ti3SiC2, boronizing treatment was carried out through powder pack cementation in the 1150-1350 °C temperature range. After boronizing treatment, one mixture layer, composed of TiB2 and SiC, forms on the surface of Ti3SiC2. The growth of the coating is processed by inward diffusion of Boron and obeys a linear rule. The Boronizing treatment increases the hardness of Ti3SiC2 from 6 GPa to 13 GPa. In the pin-on-disc test, i twas found that the material undergoes a steady-state coefficient of friction of around 0.8 and 0.45 in case of Ti3SiC2/Al2O3 tribocouple under 7 N load for the non treated and the boronized samples, respectively. The wear resistance of Ti3SiC2 under Al2O3 ball sliding has been significantly improved, which indicated that the boronizing treatment is a promising surface modification way of Ti3SiC2.

Keywords: MAX phase, boronizing, hardness, wear

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12177 Influence of Physico-Chemical Changes in the Environment on the Behavior of Tadpoles Rana Saharica: Case of Fungicide (Artea 330ec)

Authors: S. Zouainia, R. Djebar, H. Berrebah, A. Sayeb

Abstract:

This work focused on the study of physiological and biochemical changes observed in tadpoles exposed to fungicide Rana saharica Artea 330ec recently introduced in Algeria. For this, we tested the effect of xenobiotics on growth and development of tadpoles; among the studied parameters: total protein, glutathione and respiratory activity. The study of physiological parameters showed that the tadpoles change perfectly in the absence of toxic and in favorable conditions (pH, temperature). Our results showed an increased rate of protein and GSH in the presence of the fungicide Artea 330ec. The latter causes uninhibited very highly significant respiratory activity of tadpoles treated. The presence of xenobiotics in the breeding tadpoles water causes disturbances in behavior and food metabolism.

Keywords: amphibians, fungicides, pesticides, pollution

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12176 Thermal Fatigue Behavior of Austenitic Stainless Steels

Authors: Jung-Ho Moon, Tae Kwon Ha

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Continually increasing working temperature and growing need for greater efficiency and reliability of automotive exhaust require systematic investigation into the thermal fatigue properties especially of high temperature stainless steels. In this study, thermal fatigue properties of 300 series austenitic stainless steels have been evaluated in the temperature ranges of 200-800°C and 200-900°C. Systematic methods for control of temperatures within the predetermined range and measurement of load applied to specimens as a function of temperature during thermal cycles have been established. Thermal fatigue tests were conducted under fully constrained condition, where both ends of specimens were completely fixed. Load relaxation behavior at the temperatures of thermal cycle was closely related with the thermal fatigue property.

Keywords: austenitic stainless steel, automotive exhaust, thermal fatigue, microstructure, load relaxation

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12175 The Solid-Phase Sensor Systems for Fluorescent and SERS-Recognition of Neurotransmitters for Their Visualization and Determination in Biomaterials

Authors: Irina Veselova, Maria Makedonskaya, Olga Eremina, Alexandr Sidorov, Eugene Goodilin, Tatyana Shekhovtsova

Abstract:

Such catecholamines as dopamine, norepinephrine, and epinephrine are the principal neurotransmitters in the sympathetic nervous system. Catecholamines and their metabolites are considered to be important markers of socially significant diseases such as atherosclerosis, diabetes, coronary heart disease, carcinogenesis, Alzheimer's and Parkinson's diseases. Currently, neurotransmitters can be studied via electrochemical and chromatographic techniques that allow their characterizing and quantification, although these techniques can only provide crude spatial information. Besides, the difficulty of catecholamine determination in biological materials is associated with their low normal concentrations (~ 1 nM) in biomaterials, which may become even one more order lower because of some disorders. In addition, in blood they are rapidly oxidized by monoaminooxidases from thrombocytes and, for this reason, the determination of neurotransmitter metabolism indicators in an organism should be very rapid (15—30 min), especially in critical states. Unfortunately, modern instrumental analysis does not offer a complex solution of this problem: despite its high sensitivity and selectivity, HPLC-MS cannot provide sufficiently rapid analysis, while enzymatic biosensors and immunoassays for the determination of the considered analytes lack sufficient sensitivity and reproducibility. Fluorescent and SERS-sensors remain a compelling technology for approaching the general problem of selective neurotransmitter detection. In recent years, a number of catecholamine sensors have been reported including RNA aptamers, fluorescent ribonucleopeptide (RNP) complexes, and boronic acid based synthetic receptors and the sensor operated in a turn-off mode. In this work we present the fluorescent and SERS turn-on sensor systems based on the bio- or chemorecognizing nanostructured films {chitosan/collagen-Tb/Eu/Cu-nanoparticles-indicator reagents} that provide the selective recognition, visualization, and sensing of the above mentioned catecholamines on the level of nanomolar concentrations in biomaterials (cell cultures, tissue etc.). We have (1) developed optically transparent porous films and gels of chitosan/collagen; (2) ensured functionalization of the surface by molecules-'recognizers' (by impregnation and immobilization of components of the indicator systems: biorecognizing and auxiliary reagents); (3) performed computer simulation for theoretical prediction and interpretation of some properties of the developed materials and obtained analytical signals in biomaterials. We are grateful for the financial support of this research from Russian Foundation for Basic Research (grants no. 15-03-05064 a, and 15-29-01330 ofi_m).

Keywords: biomaterials, fluorescent and SERS-recognition, neurotransmitters, solid-phase turn-on sensor system

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12174 Exploration of the Possible Link Between Emotional Problems and Cholesterol Levels Among Children Diagnosed with Attention-Deficit Hyperactivity Disorder

Authors: Rosa S. Wong, Keith T.S. Tung, H.W. Tsang, Frederick K. Ho, Patrick Ip

Abstract:

Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention and hyperactive-impulsive behavior. Evidence shows that ADHD and mood problems such as depression and anxiety often co-occur and yet not everyone with ADHD reported elevated emotional problems. Given that cholesterol is essential for healthy brain development including the regions governing emotion regulation, reports found lower cholesterol levels in patients with major depressive disorder and those with suicide attempt behavior compared to healthy subjects. This study explored whether ADHD adolescents experienced more emotional problems and whether emotional problems correlated with cholesterol levels in these adolescents. This study used a portion of data from the longitudinal cohort study which was designed to investigate the long-term impact of family socioeconomic status on child development. In 2018/19, parents of 300 adolescents (average age: 12.57+/-0.49 years) were asked to rate their children’s emotional problems and report whether their children had doctor-diagnosed psychiatric diseases. We further collected blood samples from 263 children to study their lipid profile (total cholesterol, high-density lipoprotein (HDL)-cholesterol, and low-density lipoprotein (LDL)-cholesterol). Regression analyses were performed to test the relationships between variables of interest. Among 300 children, 27 (9%) had ADHD diagnosis. Analysis based on overall sample found no association between ADHD and emotional problems, but when investigating the relationship by gender, there was a significant interaction effect of ADHD and gender on emotional problems (p=0.037), with ADHD males displaying more emotional problems than ADHD females. Further analyses based on 263 children (21 with ADHD diagnosis) found significant interaction effect of ADHD and gender on total cholesterol (p=0.038) and low LDL-cholesterol levels (p=0.013) after adjusting for the child’s physical disease history. Specifically, ADHD males had significantly lower total cholesterol and low lipoprotein-cholesterol levels than ADHD females. In ADHD males, more emotional problems were associated with lower LDL-cholesterol levels (B = -4.26, 95%CI (-7.46, -1.07), p=0.013). We found preliminary support for the association between more emotional problems and lower cholesterol levels in ADHD children, especially among males. Although larger prospective studies are needed to substantiate these claims, the evidence highlights the importance of healthy lifestyle to keep cholesterol levels in normal range which can have positive effects on physical and mental health.

Keywords: attention-deficit hyperactivity disorder, cholesterol, emotional problems, adolescents

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12173 Comparative Study on the Social Behaviour of Sambar Deer (Rusa unicolor) in Captive Facilities in Peninsular Malaysia

Authors: Kushaal Selvarajah, Geetha Annavi, Mohd Noor Hisham Mohd Nadzir

Abstract:

Sambar deer (Rusa unicolor) was uplisted from Least Concern to Vulnerable by the International Union for Conservation of Nature Red list in 2015 due to drastic population decline in the wild throughout its geographical range. Sambar deer is a valued prey for the highly endangered species such as the Malayan tiger. Ex-situ conservation efforts, i.e., captive breeding, initiated by local government to boost sambar deer numbers in captivity and to reintroduce into the wild to support a higher number of tigers, consistent with the goal of our National Tiger Conservation Action Plan. The reproductive success of sambar deer and their welfare management practices in captivity are important components for effective captive breeding programs. However, there is a lack of study carried out on sambar deer in recent years and their behavior in captivity. Three captive sites (Zoo Negara, Zoo Taiping, and Sungkai Conservation Centre) were selected and observed for an average of 40 days each site (6 hours/day). A Generalized Linear Model (GLM) was used to determine the correlation between social behavior and extrinsic parameters. A comparison between all three captive sites showed the strongest correlation in behavioral variability, followed by a time of observation. This proves that there is a difference between in behavioral consistency and frequency between herds across captive sites rising to the possibility of external factors that are influential. Time of day of observation also had significant influence on certain extrinsic parameters being skewed to morning observations and this could be due to an adaptive behavior to the feeding time in the captive sites being in the morning which caused the deer to be resting towards the afternoon. Extensive study need to be done on sambar deer to pinpoint the specifics and better understanding of these possible influential factors in their behavior.

Keywords: behaviour ecology, captivity, ex-situ conservation, husbandry

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12172 Vehicle Maneuverability on Horizontal Curves on Hilly Terrain: A Study on Shillong Highway

Authors: Surendra Choudhary, Sapan Tiwari

Abstract:

The driver has two fundamental duties i) controlling the position of the vehicle along the longitudinal and lateral direction of movement ii) roadway width. Both of these duties are interdependent and are concurrently referred to as two-dimensional driver behavior. One of the main problems facing driver behavior modeling is to identify the parameters for describing the exemplary driving conduct and car maneuver under distinct traffic circumstances. Still, to date, there is no well-accepted theory that can comprehensively model the 2-D driver conduct (longitudinal and lateral). The primary objective of this research is to explore the vehicle's lateral longitudinal behavior in the heterogeneous condition of traffic on horizontal curves as well as the effect of road geometry on dynamic traffic parameters, i.e., car velocity and lateral placement. In this research, with their interrelationship, a thorough assessment of dynamic car parameters, i.e., speed, lateral acceleration, and turn radius. Also, horizontal curve road parameters, i.e., curvature radius, pavement friction, are performed. The dynamic parameters of the various types of car drivers are gathered using a VBOX GPS-based tool with high precision. The connection between dynamic car parameters and curve geometry is created after the removal of noise from the GPS trajectories. The major findings of the research are that car maneuvers with higher than the design limits of speed, acceleration, and lateral deviation on the studied curves of the highway. It can become lethal if the weather changes from dry to wet.

Keywords: geometry, maneuverability, terrain, trajectory, VBOX

Procedia PDF Downloads 146
12171 The Effect of Contextual Factors on Degree of Trust in Kuwaiti Business Organization

Authors: Ali Muhammad

Abstract:

The study investigates the effect of a number of contextual on the degree of trust within Kuwaiti business organizations. The model used in this study suggests that degree of trust within the organization is determined by four contextual variables, namely, centralization, formalization, role ambiguity, and procedural justice. Organizational trust refers to employee’ positive assumptions in regard to the goal and behaviors of other members in the organization according to organizational duties, relationships, experiences, and interrelatedness. According to the norm of reciprocity, individuals with high perceived organizational justice will be compelled to react positively to the organization in the form of higher degree of trust. The duty to exchange kindness for kindness. Based on the exchange theory, this research proposes that procedural justice, role clarity, and voice in the organization will lead to the perception of an organization’s discretionary positive treatment of employees and, in return enhances their trust in the organization. Survey data were collected from a sample of 206 employees working in Kuwaiti business organizations. Results of multiple regression analysis revealed that both organizational justice and formalization have positive effects on organizational trust. Furthermore, results indicate that lower degree of role ambiguity leads to higher degree of organizational trust. On the other hand, centralization was not found to have a significant effect on organizational trust. Implications of the findings and directions for future research are discussed.

Keywords: centralization, formalization, organizational justice, organizational trust, role ambiguity

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12170 Mathematical Model of Cancer Growth under the Influence of Radiation Therapy

Authors: Beata Jackowska-Zduniak

Abstract:

We formulate and analyze a mathematical model describing dynamics of cancer growth under the influence of radiation therapy. The effect of this type of therapy is considered as an additional equation of discussed model. Numerical simulations show that delay, which is added to ordinary differential equations and represent time needed for transformation from one type of cells to the other one, affects the behavior of the system. The validation and verification of proposed model is based on medical data. Analytical results are illustrated by numerical examples of the model dynamics. The model is able to reconstruct dynamics of treatment of cancer and may be used to determine the most effective treatment regimen based on the study of the behavior of individual treatment protocols.

Keywords: mathematical modeling, numerical simulation, ordinary differential equations, radiation therapy

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12169 Synthesis and Evaluation of Photovoltaic Properties of an Organic Dye for Dye-Sensitized Solar Cells

Authors: M. Hosseinnejad, K. Gharanjig

Abstract:

In the present study, metal free organic dyes were prepared and used as photo-sensitizers in dye-sensitized solar cells. Double rhodanine was utilized as the fundamental electron acceptor group to which electron donor aldehyde with varying substituents was attached to produce new organic dye. This dye was first purified and then characterized by analytical techniques. Spectrophotometric evaluations of the prepared dye in solution and on a nano anatase TiO2 substrate were carried out in order to assess possible changes in the status of the dyes in different environments. The results show that the dye form j-type aggregates on the nano TiO2. Additionally, oxidation potential measurements were also carried out. Finally, dye sensitized solar cell based on synthesized dye was fabricated in order to determine the photovoltaic behavior and conversion efficiency of individual dye.

Keywords: conversion efficiency, dye-sensitized solar cell, photovoltaic behavior, sensitizer

Procedia PDF Downloads 188
12168 Study of Ion Density Distribution and Sheath Thickness in Warm Electronegative Plasma

Authors: Rajat Dhawan, Hitendra K. Malik

Abstract:

Electronegative plasmas comprising electrons, positive ions, and negative ions are advantageous for their expanding applications in industries. In plasma cleaning, plasma etching, and plasma deposition process, electronegative plasmas are preferred because of relatively less potential developed on the surface of the material under investigation. Also, the presence of negative ions avoid the irregularity in etching shapes and also enhance the material working during the fabrication process. The interaction of metallic conducting surface with plasma becomes mandatory to understand these applications. A metallic conducting probe immersed in a plasma results in the formation of a thin layer of charged species around the probe called as a sheath. The density of the ions embedded on the surface of the material and the sheath thickness are the important parameters for the surface-plasma interaction. Sheath thickness will give rise to the information of affected plasma region due to conducting surface/probe. The knowledge of the density of ions in the sheath region is advantageous in plasma nitriding, and their temperature is equally important as it strongly influences the thickness of the modified layer during surface plasma interaction. In the present work, we considered a negatively biased metallic probe immersed in a warm electronegative plasma. For this system, we adopted the continuity equation and momentum transfer equation for both the positive and negative ions, whereas electrons are described by Boltzmann distribution. Finally, we use the Poisson’s equation. Here, we assumed the spherical geometry for small probe radius. Poisson’s equation reveals the behaviour of potential surrounding a conducting metallic probe along with the use of the continuity and momentum transfer equations, with the help of proper boundary conditions. In turn, it gives rise to the information about the density profile of charged species and most importantly the thickness of the sheath. By keeping in mind, the well-known Bohm-Sheath criterion, all calculations are done. We found that positive ion density decreases with an increase in positive ion temperature, whereas it increases with the higher temperature of the negative ions. Positive ion density decreases as we move away from the center of the probe and is found to show a discontinuity at a particular distance from the center of the probe. The distance where discontinuity occurs is designated as sheath edge, i.e., the point where sheath ends. These results are beneficial for industrial applications, as the density of ions embedded on material surface is strongly affected by the temperature of plasma species. It has a drastic influence on the surface properties, i.e., the hardness, corrosion resistance, etc. of the materials.

Keywords: electronegative plasmas, plasma surface interaction positive ion density, sheath thickness

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12167 Assessment of the Impact of Road Transportation Improvement on Rural Development

Authors: Mohammad Mirwais Arghandiwal, Fujita Motohiro, Wisinee Wisetjindawat

Abstract:

Since 2001, the new government of Afghanistan addressed the improvement of transportation in rural areas as one of the key issues for the country development. This paper thus, aims to show the impotency of transportation in the rural area of Kabul province. A field survey in Kabul Province capital of Afghanistan has been conducted during March, 2015, and 201 questionnaires were collected from four districts named Shakar Dara, Paghman, Char Asyab, and Khak Jabar to investigate the impacts of road transportation on the people’s daily life. The districts had their road projects constructed during the last 3-5 years. The interviewees are chosen randomly from a different category of districts residences. As transportation is one of the most important factors for the development of the communities, during the survey it was very easily to observe a positive effect on the life of people. The improvement on the accessibility has had a positive impact on the land and land price. In this paper, a model is created to show the relationship between different factors and the land price improvement. In the end, a recommendation is presented on the establishment of the community council for a better use and maintenance of road projects. We emphasize on a public and private partnership at a community level in the districts during the construction period too. In addition, the communities should be encouraged on their positive role in the improvement of transportation through their participation and collaboration with the local government.

Keywords: accessibility, Afghanistan, poverty, rural area, transportation development

Procedia PDF Downloads 445