Search results for: stress intensity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5569

Search results for: stress intensity

2929 Effects of Tool State on the Output Parameters of Front Milling Using Discrete Wavelet Transform

Authors: Bruno S. Soria, Mauricio R. Policena, Andre J. Souza

Abstract:

The state of the cutting tool is an important factor to consider during machining to achieve a good surface quality. The vibration generated during material cutting can also directly affect the surface quality and life of the cutting tool. In this work, the effect of mechanical broken failure (MBF) on carbide insert tools during face milling of AISI 304 stainless steel was evaluated using three levels of feed rate and two spindle speeds for each tool condition: three carbide inserts have perfect geometry, and three other carbide inserts have MBF. The axial and radial depths remained constant. The cutting forces were determined through a sensory system that consists of a piezoelectric dynamometer and data acquisition system. Discrete Wavelet Transform was used to separate the static part of the signals of force and vibration. The roughness of the machined surface was analyzed for each machining condition. The MBF of the tool increased the intensity and force of vibration and worsened the roughness factors.

Keywords: face milling, stainless steel, tool condition monitoring, wavelet discrete transform

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2928 Feasibility Study to Enhance the Heat Transfer in a Typical Pressurized Water Reactor by Ribbed Spacer Grids

Authors: A. Ghadbane, M. N. Bouaziz, S. Hanini, B. Baggoura, M. Abbaci

Abstract:

The spacer grids are used to fix the rods bundle in a nuclear reactor core also act as turbulence-enhancing devices to improve the heat transfer from the hot surfaces of the rods to the surrounding coolant stream. Therefore, the investigation of thermal-hydraulic characteristics inside the rod bundles is important for optima design and safety operation of a nuclear reactor power plant. This contribution presents a feasibility study to use the ribbed spacer grids as mixing devices. The present study evaluates the effects of different ribbed spacer grids configurations on flow pattern and heat transfer in the downstream of the mixing devices in a 2 x 2 rod bundle array. This is done by obtaining velocity and pressure fields, turbulent intensity and the heat transfer coefficient using a three-dimensional CFD analysis. Numerical calculations are performed by employing K-ε turbulent model. The computational results obtained are promising and the comparison with standard spacer grids shows a clear difference which required the experimental approach to validate.

Keywords: PWR fuel assembly, spacer grid, mixing vane, swirl flow, turbulent heat transfer, CFD

Procedia PDF Downloads 488
2927 Uses and Gratification with the Website Secret-thai.com

Authors: Siriporn Meenanan

Abstract:

The objective of this study is to study about the uses and gratification of the sample who use the website that named secret-thai.com which provides moral contents, inspires, and builds up the spirit. The study found that the samples mainly use this website to follow up on the dharma activities. They also use the space as the web board to discuss about dharma issues. Moreover, the contents help readers to relax and also provides the guidelines to deal with stress and uncomfortable situations properly. The samples found to be most satisfied. In other words, the samples found the contents of the website are complete, and can cover their needs. Moreover, they found that contents useful in their ways of living. In addition, they are satisfied with the beautiful and interesting design of the website and well classification of the contents that readers can easily find the information that they want.

Keywords: uses and gratification, website, Secret-Thai.com, moral contents

Procedia PDF Downloads 236
2926 Men's Intimate Violence: Theory and Practice Relationship

Authors: Omer Zvi Shaked

Abstract:

Intimate Partner Violence (IPV) is a widespread social problem. Since the 1970's, and due to political changes resulting from the feminist movement, western society has been changing its attitude towards the phenomenon and has been taking an active approach to reduce its magnitude. Enterprises in the form of legislation, awareness and prevention campaigns, women's shelters, and community intervention programs became more prevalent as years progressed. Although many initiatives were found to be productive, the effectiveness of one, however, remained questionable throughout the years: intervention programs for men's intimate violence. Surveys outline two main intervention models for men's intimate violence. The first is the Duluth model, which argued that men are socialized to be dominant - while women are socialized to be subordinate - and men are therefore required by social imperative to enforce, physically if necessary, their dominance. The Duluth model became the chief authorized intervention program, and some states in the US even regulated it as the standard criminal justice program for men's intimate violence. However, meta-analysis findings demonstrated that based on a partner's reports, Duluth treatment completers have 44% recidivism rate, and between 40% and 85% dropout range. The second model is the Cognitive-Behavioral Model (CBT), which is a highly accepted intervention worldwide. The model argues that cognitive misrepresentations of intimate situations precede violent behaviors frequently when anger predisposition exists. Since anger dysregulation mediates between one's cognitive schemes and violent response, anger regulation became the chief purpose of the intervention. Yet, a meta-analysis found only a 56% risk reduction for CBT interventions. It is, therefore, crucial to understand the background behind the domination of both the Duluth model and CBT interventions. This presentation will discuss the ways in which theoretical conceptualizations of men's intimate violence, as well as ideologies, had contributed to the above-mentioned interventions' wide acceptance, despite known lack of scientific and evidential support. First, the presentation will review the prominent interventions for male intimate violence, the Duluth model, and CBT. Second, the presentation will review the prominent theoretical models explaining men's intimate violence: The Patriarchal model, the Abusive Personality model, and the Post-Traumatic Stress model. Third, the presentation will discuss the interrelation between theory and practice, and the nature of affinity between research and practice regarding men's intimate violence. Finally, the presentation will set new directions for further research, aiming to improve intervention's efficiency with men's intimate violence and advance social work practice in the field.

Keywords: intimate partner violence, theory and practice relationship, Duluth, CBT, abusive personality, post-traumatic stress

Procedia PDF Downloads 127
2925 Mueller Matrix Polarimetry for Analysis Scattering Biological Fluid Media

Authors: S. Cherif, A. Medjahed, M. Bouafia, A. Manallah

Abstract:

A light wave is characterized by 4 characteristics: its amplitude, its frequency, its phase and the direction of polarization of its luminous vector (the electric field). It is in this last characteristic that we will be interested. The polarization of the light was introduced in order to describe the vectorial behavior of the light; it describes the way in which the electric field evolves in a point of space. Our work consists in studying diffusing mediums. Different types of biological fluids were selected to study the evolution of each with increasing scattering power of the medium, and in the same time to make a comparison between them. When crossing these mediums, the light undergoes modifications and/or deterioration of its initial state of polarization. This phenomenon is related to the properties of the medium, the idea is to compare the characteristics of the entering and outgoing light from the studied medium by a white light. The advantage of this model is that it is experimentally accessible workable intensity measurements with CCD sensors and allows operation in 2D. The latter information is used to discriminate some physical properties of the studied areas. We chose four types of milk to study the evolution of each with increasing scattering power of the medium.

Keywords: light polarization, Mueller matrix, Mueller images, diffusing medium, milk

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2924 Numerical Simulation of Solar Reactor for Water Disinfection

Authors: A. Sebti Bouzid, S. Igoud, L. Aoudjit, H. Lebik

Abstract:

Mathematical modeling and numerical simulation have emerged over the past two decades as one of the key tools for design and optimize performances of physical and chemical processes intended to water disinfection. Water photolysis is an efficient and economical technique to reduce bacterial contamination. It exploits the germicidal effect of solar ultraviolet irradiation to inactivate pathogenic microorganisms. The design of photo-reactor operating in continuous disinfection system, required tacking in account the hydrodynamic behavior of water in the reactor. Since the kinetic of disinfection depends on irradiation intensity distribution, coupling the hydrodynamic and solar radiation distribution is of crucial importance. In this work we propose a numerical simulation study for hydrodynamic and solar irradiation distribution in a tubular photo-reactor. We have used the Computational Fluid Dynamic code Fluent under the assumption of three-dimensional incompressible flow in unsteady turbulent regimes. The results of simulation concerned radiation, temperature and velocity fields are discussed and the effect of inclination angle of reactor relative to the horizontal is investigated.

Keywords: solar water disinfection, hydrodynamic modeling, solar irradiation modeling, CFD Fluent

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2923 Physicochemical and Antioxidative Characteristics of Black Bean Protein Hydrolysates Obtained from Different Enzymes

Authors: Zhaojun Zheng, Yuanfa Liu, Jiaxin Li, Jinwei Li, Yong-jiang Xu, Chen Cao

Abstract:

Black bean is an excellent protein source for preparing hydrolysates, which attract much attention due to their biological activity. The objective of this study was to characterize the physicochemical and antioxidant properties of black bean protein, hydrolyzed by ficin, bromelain or alcalase until 300 min of hydrolysis. Results showed that bromelain and alcalase hydrolysates possessed a higher degree of hydrolysis (DH) than that of ficin, thereby presenting different ultraviolet absorption, fluorescence intensity, and circular dichroism. Moreover, all hydrolysates possessed the capacity to scavenge DPPH radical with the lowest IC₅₀ of 21.11 µg/mL, as well as to chelate ferrous ion (Fe²⁺) with the IC₅₀ values ranging from 6.82 to 30.68 µg/mL. Intriguingly, the oxidation of linoleic acid, sunflower oil, and sunflower oil-in-water emulsion was remarkedly retarded by the three selected protein hydrolysates, especially by bromelain-treated protein hydrolysate, which might attribute to their high hydrophobicity and emulsifying properties. These findings can provide strong support for black bean protein hydrolysates to be employed in food products acting as natural antioxidant alternatives.

Keywords: antioxidant activity, black bean protein hydrolysate, emulsion physicochemical properties, sunflower oil

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2922 Understanding the Impact of Resilience Training on Cognitive Performance in Military Personnel

Authors: Haji Mohammad Zulfan Farhi Bin Haji Sulaini, Mohammad Azeezudde’en Bin Mohd Ismaon

Abstract:

The demands placed on military athletes extend beyond physical prowess to encompass cognitive resilience in high-stress environments. This study investigates the effects of resilience training on the cognitive performance of military athletes, shedding light on the potential benefits and implications for optimizing their overall readiness. In a rapidly evolving global landscape, armed forces worldwide are recognizing the importance of cognitive resilience alongside physical fitness. The study employs a mixed-methods approach, incorporating quantitative cognitive assessments and qualitative data from military athletes undergoing resilience training programs. Cognitive performance is evaluated through a battery of tests, including measures of memory, attention, decision-making, and reaction time. The participants, drawn from various branches of the military, are divided into experimental and control groups. The experimental group undergoes a comprehensive resilience training program, while the control group receives traditional physical training without a specific focus on resilience. The initial findings indicate a substantial improvement in cognitive performance among military athletes who have undergone resilience training. These improvements are particularly evident in domains such as attention and decision-making. The experimental group demonstrated enhanced situational awareness, quicker problem-solving abilities, and increased adaptability in high-stress scenarios. These results suggest that resilience training not only bolsters mental toughness but also positively impacts cognitive skills critical to military operations. In addition to quantitative assessments, qualitative data is collected through interviews and surveys to gain insights into the subjective experiences of military athletes. Preliminary analysis of these narratives reveals that participants in the resilience training program report higher levels of self-confidence, emotional regulation, and an improved ability to manage stress. These psychological attributes contribute to their enhanced cognitive performance and overall readiness. Moreover, this study explores the potential long-term benefits of resilience training. By tracking participants over an extended period, we aim to assess the durability of cognitive improvements and their effects on overall mission success. Early results suggest that resilience training may serve as a protective factor against the detrimental effects of prolonged exposure to stressors, potentially reducing the risk of burnout and psychological trauma among military athletes. This research has significant implications for military organizations seeking to optimize the performance and well-being of their personnel. The findings suggest that integrating resilience training into the training regimen of military athletes can lead to a more resilient and cognitively capable force. This, in turn, may enhance mission success, reduce the risk of injuries, and improve the overall effectiveness of military operations. In conclusion, this study provides compelling evidence that resilience training positively impacts the cognitive performance of military athletes. The preliminary results indicate improvements in attention, decision-making, and adaptability, as well as increased psychological resilience. As the study progresses and incorporates long-term follow-ups, it is expected to provide valuable insights into the enduring effects of resilience training on the cognitive readiness of military athletes, contributing to the ongoing efforts to optimize military personnel's physical and mental capabilities in the face of ever-evolving challenges.

Keywords: military athletes, cognitive performance, resilience training, cognitive enhancement program

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2921 Effect of Selenium Source on Meat Quality of Bonsmara Bull Calves

Authors: J. van Soest, B. Bruneel, J. Smit, N. Williams, P. Swiegers

Abstract:

Selenium (Se) is an essential trace mineral involved in reducing oxidative stress, enhancing immune status, improving reproduction, and regulating growth. During finishing period, selenium supplementation can be applied to improve meat quality. Dietary selenium can be provided in inorganic or organic forms. Specifically, L-selenomethionine (organic selenium) allows for selenium storage in animal protein which supports the animal during periods of high oxidative stress. The objective of this study was to investigate the effects of synthetically produced, single amino acid, L-selenomethionine (Excential Selenium 4000, Orffa Additives BV) on production parameters, health status, and meat quality of Bonsmara bull calves. 24 calves, 7 months of age, completed a 60-day initial growing period at a commercial feedlot, after which they were transported to research station Rumen-8 (Bethlehem, South-Africa). After a ten-day adaptation period, the bulls were allocated to a control (n=12) or treatment (n=12) group. Each group was divided over 3 pens based on weight. Both groups received Total Mixed Ration supplemented with 5.25 mg Se/head per day. The control group was supplemented with sodium selenite as Se source, whilst the treatment group was supplemented with L-selenomethionine (Excential Selenium 4000, Orffa Additives BV). Animals were limited to 10 kg feed intake per head per day to ensure similar Se intake. Treatment period lasted 1.5 months. A beta-adrenergic agonist was included in the feed for the last 30 days. During the treatment period, average daily gain, average daily feed intake, and feed conversion ratio were recorded. Blood parameters were measured at day 1, day 25, and before slaughter (day 47). After slaughter, carcass weight, dressing percentage, grading, and meat quality (pH, tenderness, colour, odour, purge, proximate analyses, acid detergent fibre, and neutral detergent fibre) were determined. No differences between groups were found in performance. A higher number of animals with cortisol levels below detection limit (27.6 nmol/l) was recorded for the treatment group. Other blood parameters showed no differences. No differences were found regarding carcass weight and dressing percentage. Important parameters of meat quality were significantly improved in the treatment group: instrumental tenderness at 14 days ageing was 2.8 and 3.4 for treatment and control respectively (P=0.010), and a 0.5% decrease in purge (of fresh samples) was shown, 1.5% and 2.0% for treatment group and control respectively (p=0.029). Besides, pH was shown to be numerically reduced in the treatment group. In summary, supplementation with L-selenomethionine as selenium source improved meat quality compared to sodium selenite. Lower instrumental tenderness (Warner Bratzler Shear Force, WBSF) was recorded for the treatment group. This indicates less tough meat and highest consumer satisfaction. Regarding purge, control was just below 2.0%, an important threshold for consumer acceptation. Treatment group scored 0.5% lower for purge than control, indicating higher consumer satisfaction. The lower pH in the treatment group could be an indication of higher glycogen reserves in muscle which could contribute to a reduced risk of Dark Firm Dry carcasses. More animals showed cortisol levels below detection limit in the treatment group, indicating lower levels of stress when animals receive L-selenomethionine.

Keywords: calves, meat quality, nutrition, selenium

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2920 Colorimetric Detection of Ceftazdime through Azo Dye Formation on Polyethylenimine-Melamine Foam

Authors: Pajaree Donkhampa, Fuangfa Unob

Abstract:

Ceftazidime is an antibiotic drug commonly used to treat several human and veterinary infections. However, the presence of ceftazidime residues in the environment may induce microbial resistance and cause side effects to humans. Therefore, monitoring the level of ceftazidime in environmental resources is important. In this work, a melamine foam platform was proposed for simultaneous extraction and colorimetric detection of ceftazidime based on the azo dye formation on the surface. The melamine foam was chemically modified with polyethyleneimine (PEI) and characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Ceftazidime is a sample that was extracted on the PEI-modified melamine foam and further reacted with nitrite in an acidic medium to form an intermediate diazonium ion. The diazotized molecule underwent an azo coupling reaction with chromotropic acid to generate a red-colored compound. The material color changed from pale yellow to pink depending on the ceftazidime concentration. The photo of the obtained material was taken by a smartphone camera and the color intensity was determined by Image J software. The material fabrication and ceftazidime extraction and detection procedures were optimized. The detection of a sub-ppm level of ceftazidime was achieved without using a complex analytical instrument.

Keywords: colorimetric detection, ceftazidime, melamine foam, extraction, azo dye

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2919 Formation of Nanostructured Surface Layers of a Material with TiNi-Based Shape Memory by Diffusion Metallization

Authors: Zh. M. Blednova, P. O. Rusinov

Abstract:

Results of research on the formation of the surface layers of a material with shape memory effect (SME) based on TiNi diffusion metallization in molten Pb-Bi under isothermal conditions in an argon atmosphere are presented. It is shown that this method allows obtaining of uniform surface layers in nanostructured state of internal surfaces on the articles of complex shapes with stress concentrators. Structure, chemical and phase composition of the surface layers provide a manifestation of TiNi shape memory. The average grain size of TiNi coatings ranges between 60 ÷ 160 nm.

Keywords: diffusion metallization, nikelid titanium surface layers, shape memory effect, nanostructures

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2918 Numerical Investigation of Electrohydrodynamics: Enhanced Heat Transfer in a Solid Sample

Authors: Suwimon Saneewong Na Ayuttaya

Abstract:

This paper presents a numerical investigation of electrically driven flow for enhancing convective heat transfer in a channel flow. This study focuses on the electrode arrangements, number of electrode and electrical voltage on Electrohydrodynamics (EHD) and effect of airflow driven on solid sample surface. The inlet airflow and inlet temperature are 0.35 m/s and 60 oC, respectively. High electrical voltage is tested in the range of 0-30 kV and number of electrode is tested in the range of 1-5. The numerical results show that electric field intensity is depended on electrical voltage and number of electrode. Increasing number of electrodes is increased shear flow, so swirling flow is increased. The swirling flows from aligned and staggered arrangements are affecting within the solid sample. When electrical voltage is increased, temperature distribution and convective heat transfer on the solid sample are significantly increased due to the electric force much stronger.

Keywords: electrohydrodynamics (EHD), swirling flow, convective heat transfer, solid sample

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2917 Mechanical Properties of Biological Tissues

Authors: Young June Yoon

Abstract:

We will present four different topics in estimating the mechanical properties of biological tissues. First we elucidate the viscoelastic behavior of collagen molecules whose diameter is a couple of nanometers. By using the molecular dynamics simulation, we observed the viscoelastic behavior in different pulling velocity. Second, the protein layer, so called ‘sheath’ in enamel microstructure reduces the stress concentration in enamel minerals. We examined the result by using the finite element methods. Third, the anisotropic elastic constants of dentin are estimated by micromechanical analysis and estimated results are close to the experimentally measured data. Last, new formulation between the fabric tensor and the wave velocity is established for calcaneus by employing the poroelasticity. This formulation can be simply used for future experiments.

Keywords: tissues, mechanics, mechanical properties, wave propagation

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2916 Comparing Performance of Irrigation System in Nepal by Collective Action and Decision-Making Capacity of the Farmers

Authors: Manita Ale, Ganesh P. Shivakoti, Ram C. Bastakoti

Abstract:

Irrigation system, a system for enhancing agricultural productivity, requires regular maintenance in order to avoid irregular allocation of water. For maintenance of the system in long run, farmers’ participation plays a key role increasing the performance of system. The performance of any irrigation system mainly relies on various factors which affect collective action plus decision making, as well as their shared impacts. The paper consists of system level information that were collected from 12 Irrigation Systems (IS) from three-sampled districts of Nepal and the household information that were collected from 160 irrigation water users. The results reveal that, out of 12 sampled irrigation systems, only 4 systems shows high performance levels. The high performance level of those systems was characterized on the basis of adequate availability of water, good maintenance of system infrastructure, and conformance to existing rules followed. In addition, the paper compares different irrigation systems based on trust, reciprocity, cropping intensity, command area and yield as tools to indicate the importance of collective action in performance of irrigation system.

Keywords: collective action, decision-making, farmers’ participation, performance

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2915 Alteration of Bone Strength in Osteoporosis of Mouse Femora: Computational Study Based on Micro CT Images

Authors: Changsoo Chon, Sangkuy Han, Donghyun Seo, Jihyung Park, Bokku Kang, Hansung Kim, Keyoungjin Chun, Cheolwoong Ko

Abstract:

The purpose of the study is to develop a finite element model based on 3D bone structural images of Micro-CT and to analyze the stress distribution for the osteoporosis mouse femora. In this study, results of finite element analysis show that the early osteoporosis of mouse model decreased a bone density in trabecular region; however, the bone density in cortical region increased.

Keywords: micro-CT, finite element analysis, osteoporosis, bone strength

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2914 Urinary Schistosomiasis among Pre-School and School Aged Children in Two Peri-Urban Communities in Southwest Nigeria

Authors: Isiaka Akinwale, Tolulope Babatunde, Oladepo Sowemimo

Abstract:

A cross-sectional study was conducted between March and April, 2016 among pre-school and school-aged children in two peri-urban communities in Osun State, Southwest Nigeria. Urine samples were collected from the pre-school and school-aged children, tested for microhaematuria using reagent strips, processed and examined for Schistosoma haematobium ova. Out of 274 pupils examined, 132 (48.2%) had infection, with no statistically significant difference (P > 0.05) in infection between male (48.6%) and female pupils (47.6%). The prevalence of infection increases significantly with age (P < 0.05), with the peak (93.3%) of infection recorded in pupils aged 15 to 16 years and the lowest infection (10.0%) in pupils aged 3 to 4 years. There was no statistically significant association (P > 0.05) between intensity in male pupils (156.0 ± 34.5/10 ml) and female pupils (141.7 ± 29.5/10 ml). The prevalence of pupils with microhaematuria was 65.0% and it increased significantly with age (P < 0.001). The conclusion drawn from the study is that to reduce the transmission of S. haematobium in endemic communities, health education and provision of potable water are advocated.

Keywords: Schistosoma haematobium, microhaeamturia, prevalence, urinary schistosomiasis, school aged children, Nigeria

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2913 Enhancement in Seebeck Coefficient of MBE Grown Un-Doped ZnO by Thermal Annealing

Authors: M. Asghar, K. Mahmood, F. Malik, Lu Na, Y-H Xie, Yasin A. Raja, I. Ferguson

Abstract:

In this paper, we have reported an enhancement in Seebeck coefficient of un-doped zinc oxide (ZnO) grown by molecular beam epitaxy (MBE) on silicon (001) substrate by annealing treatment. The grown ZnO thin films were annealed in oxygen environment at 500°C – 800°C, keeping a step of 100°C for one hour. Room temperature Seebeck measurements showed that Seebeck coefficient and power factor increased from 222 to 510 µV/K and 8.8×10^-6 to 2.6×10^-4 Wm^-1K^-2 as annealing temperature increased from 500°C to 800°C respectively. This is the highest value of Seebeck coefficient ever reported for un-doped MBE grown ZnO according to best of our knowledge. This observation was related with the improvement of crystal structure of grown films with annealing temperature. X-ray diffraction (XRD) results demonstrated that full width half maximum (FWHM) of ZnO (002) plane decreased and crystalline size increased as the annealing temperature increased. Photoluminescence study revealed that the intensity of band edge emission increased and defect emission decreased as annealing temperature increased because the density of oxygen vacancy related donor defects decreased with annealing temperature. This argument was further justified by the Hall measurements which showed a decreasing trend of carrier concentration with annealing temperature.

Keywords: ZnO, MBE, thermoelectric properties, annealing temperature, crystal structure

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2912 Study of Toxic Effect and Anti-Oxidative Activity of a β- Amidophosphonates

Authors: Houria Djebar, Amina Saib, Malika Berredjem, Khaoula Bechlem, Mohammed-Reda Djebar

Abstract:

Reactive oxygen species (ROS) have a high potential to damage almost all types of cellular components of the body, which explains their involvement in the induction and/or amplification of several pathologies. Supplementation of the body by exogenous antioxidants is very useful against these harmful species. In this context, we attempted to evaluate the in vitro and in vivo antioxidant activities of three newly synthesized amidophosphonates (AP1, AP2, and AP3). The results relating to the in vitro tests for DPPH radical scavenging activity shows that these amidophosphonates have a modest antiradical power (ARP) less effectively pronounced compared with an analogue marketed in Algeria: (Dursban) Clorpiryphos ethyl. However, in vivo effects were evaluated on some antioxidant systems (LP intensity, CAT activity and GSH content), or in combination with 2, 2-diphenyl-picrylhydrazyle (DPPH) radical in paramecium tetraurelia used as a complementary system to rapidly elucidate the cytotoxicity. On the basis of the results obtained it can be concluded that amidophosphonates studied exhibited a mild protective effect. The mechanism for how they influenced the antioxidant activities was discussed.

Keywords: Paramecium tetraurelia, amidophosphonates, antioxidant activity, DPPH free radical, in vitro experiments, biochemical parameters

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2911 Monitoring of Key Indicators of Sustainable Tourism in the Jalapão State Park/Tocantins: A Case Study of Environmental Indicators

Authors: Veruska C. Dutra, Afonso R. Aquino

Abstract:

Since the 1980s, global tourism activity has consolidated worldwide to become an important economic contributor, and consequently, the sociocultural and environmental impacts are starting to become evidenced. This raises the need of discussing about actions for sustainable tourism that should be linked not only to the economy, but also to the environment and social aspects. The work that is going to be presented is part of a doctoral research project in Sciences undertaken at the Sao Paulo University, Brazil. It aims to analyze whether the monitoring of the tourism sector with a focus on sustainability is applicable or not, through those indicators, put in a case study in the Jalapão State Park (JSP) conservation unit, in the state of Tocantins, Brazil. This is a study of an interdisciplinary nature that had the deductive method as its guide. We concluded that the key points of the sustainable tourism, when analyzed with the focal point in environmental indicators, are an important evaluation and quantification tool of that activity in the study locus. It displayed itself as an adequate tool for monitoring, thus decoding, the main environmental impacts that occur in tourism regions and their intensity, which is made possible through analysis, and has the objective to trace ways to prevent and correct the presented impacts.

Keywords: indicators, tourism, sustainability, Jalapão

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2910 Bayes Estimation of Parameters of Binomial Type Rayleigh Class Software Reliability Growth Model using Non-informative Priors

Authors: Rajesh Singh, Kailash Kale

Abstract:

In this paper, the Binomial process type occurrence of software failures is considered and failure intensity has been characterized by one parameter Rayleigh class Software Reliability Growth Model (SRGM). The proposed SRGM is mathematical function of parameters namely; total number of failures i.e. η-0 and scale parameter i.e. η-1. It is assumed that very little or no information is available about both these parameters and then considering non-informative priors for both these parameters, the Bayes estimators for the parameters η-0 and η-1 have been obtained under square error loss function. The proposed Bayes estimators are compared with their corresponding maximum likelihood estimators on the basis of risk efficiencies obtained by Monte Carlo simulation technique. It is concluded that both the proposed Bayes estimators of total number of failures and scale parameter perform well for proper choice of execution time.

Keywords: binomial process, non-informative prior, maximum likelihood estimator (MLE), rayleigh class, software reliability growth model (SRGM)

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2909 An Exploratory Study on the Effect of a Fermented Dairy Product on Self-Reported Gut Complaints in US Recreational Athletes

Authors: Kersch-Counet C., Fransen K. H. S., Broyd M., Nyakayiru J. D. O. A., Schoemaker M. H., Mallee L. F., Bovee-Oudenhoven I. M. J.

Abstract:

Background: Around one third of people, including athletes, suffer from feelings of gut discomfort. Fermentation of dairy is a process that has been associated with products that can improve gut health. However, insight in (potential) health benefits of most fermented foods is limited to chemical analyses and in-vitro models. Objective: The aim of this open-label, single-arm explorative trial was to investigate in a real life setting the effect of consumption of a fermented whey product for 3 weeks on self-perceived physical and mental wellbeing and digestive issues in 150 US recreational athletes (20-50 years of age) with self-reported gut complaints at enrolment. Methods: Participants living at the West-Coast of the US received for 3 weeks a daily powder of 15 g of BiotisTM Fermentis to be mixed in water using a supplied shaker. Weekly questionnaires were conducted by MMR research to study the effect on physical/mental health issues and self-perceived gut complaints. Non-parametric tests (e.g., Friedman test) were used to assess statistical differences over time while the Kruskal-Wallis and Wilcoxon signed-rank tests were used for sub-groups analysis. Results: Bloating, stress and anxiety were the top 3 issues of the US recreational athletes. Satisfaction of physical wellbeing increased significantly throughout the 3-weeks of fermented whey product consumption (p<0.0005). Combined digestive issues decreased significantly after 2- and 3-weeks of product consumption, with bloating showing a significant reduction (p<0.05). There was a trend that self-reported stress levels reduced after 3 weeks and participants said to significantly feel more active, energetic, and vital (p<0.05). Subgroup analysis showed that gender and habitual protein supplement consumption were associated with specific health issues and modulated the response to the fermented dairy product. Conclusion: Daily consumption of the fermented BiotisTM Fermentis product is associated with a reduction in self-perceived gastrointestinal symptoms and improved overall wellbeing and mood state in US recreational athletes. This large nutrition and health consumer study brings valuable insights in self-reported gut complaints of recreational athletes in the US and their response to a fermented dairy product. A controlled clinical trial in a targeted population is recommended to scientifically substantiate the product effect as observed in this explorative study.

Keywords: real-life study, digestive health, fermented whey, sports

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2908 Numerical Simulation of Truck Collision with Road Blocker

Authors: Engin Metin Kaplan, Kemal Yaman

Abstract:

In this study, the crash of a medium heavy vehicle onto a designed Road blocker (vehicle barrier) is studied numerically. Structural integrity of the Road blocker is studied by nonlinear dynamic methods under the loading conditions which are defined in the standards. NASTRAN® and LS-DYNA® which are commercial software are used to solve the problem. Outer geometry determination, alignment of the inner part and material properties of the road blocker are studied linearly to yield design parameters. Best design parameters are determined to achieve the most structurally optimized road blocker. Strain and stress values of the vehicle barrier are obtained by solving the partial differential equations.

Keywords: vehicle barrier, truck collision, road blocker, crash analysis

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2907 Determination of Small Shear Modulus of Clayey Sand Using Bender Element Test

Authors: R. Sadeghzadegan, S. A. Naeini, A. Mirzaii

Abstract:

In this article, the results of a series of carefully conducted laboratory test program were represented to determine the small strain shear modulus of sand mixed with a range of kaolinite including zero to 30%. This was experimentally achieved using a triaxial cell equipped with bender element. Results indicate that small shear modulus tends to increase, while clay content decreases and effective confining pressure increases. The exponent of stress in the power model regression analysis was not sensitive to the amount of clay content for all sand clay mixtures, while coefficient A was directly affected by change in clay content.

Keywords: small shear modulus, bender element test, plastic fines, sand

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2906 Barriers and Opportunities in Apprenticeship Training: How to Complete a Vocational Upper Secondary Qualification with Intermediate Finnish Language Skills

Authors: Inkeri Jaaskelainen

Abstract:

The aim of this study is to shed light on what is it like to study in apprenticeship training using intermediate (or even lower level) Finnish. The aim is to find out and describe these students' experiences and feelings while acquiring a profession in Finnish as it is important to understand how immigrant background adult learners learn and how their needs could be better taken into account. Many students choose apprenticeships and start vocational training while their language skills in Finnish are still very weak. At work, students should be able to simultaneously learn Finnish and do vocational studies in a noisy, demanding, and stressful environment. Learning and understanding new things is very challenging under these circumstances, and sometimes students get exhausted and experience a lot of stress - which makes learning even more difficult. Students are different from each other, and so are their ways to learn. Both duties at work and school assignments require reasonably good general language skills, and, especially at work, language skills are also a safety issue. The empirical target of this study is a group of students with an immigrant background who studied in various fields with intensive L2 support in 2016–2018 and who by now have completed a vocational upper secondary qualification. The interview material for this narrative study was collected from those who completed apprenticeship training in 2019–2020. The data collection methods used are a structured thematic interview, a questionnaire, and observational data. Interviewees with an immigrant background have an inconsistent cultural and educational background - some have completed an academic degree in their country of origin while others have learned to read and write only in Finland. The analysis of the material utilizes thematic analysis, which is used to examine learning and related experiences. Learning a language at work is very different from traditional classroom teaching. With evolving language skills, at an intermediate level at best, rushing and stressing makes it even more difficult to understand and increases the fear of failure. Constant noise, rapidly changing situations, and uncertainty undermine the learning and well-being of apprentices. According to preliminary results, apprenticeship training is well suited to the needs of an adult immigrant student. In apprenticeship training, students need a lot of support for learning and understanding a new communication and working culture. Stress can result in, e.g., fatigue, frustration, and difficulties in remembering and understanding. Apprenticeship training can be seen as a good path to working life. However, L2 support is a very important part of apprenticeship training, and it indeed helps students to believe that one day they will graduate and even get employed in their new country.

Keywords: apprenticeship training, vocational basic degree, Finnish learning, wee-being

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2905 Removal of Oxytetracycline Using Sonophotocatalysis: Parametric Study

Authors: Bouafia-Chergui Souâd, Chabani Malika, Bensmaili Aicha

Abstract:

Water treatment and especially, medicament pollutants are nowadays important problems. Degradation of oxytetracycline was carried out using combined process of low-frequency ultrasound (US), ultraviolet irradiation and a catalyst. The effectiveness of the coupled processes has been evaluated by studying the effects of various operating parameters including initial OTC concentration, solution pH and catalyst mass. For the photolysis process, the monochromatic ultraviolet light wavelength utilized was 365 nm. The sonolysis experiments were performed with ultrasound at a frequency of 40 kHz. The heterogeneous photocatalysis was studied in the presence of TiO2. The processes were employed individually, and simultaneously to examine the details of the processes and to investigate the contribution of each process. Low UV intensity (12W), low pH and high mass of TiO2 conditions enhanced the sono-photocatalytic degradation of OTC. The results showed that the individual contribution sonochemical and photochemical reactions are very low, however, their coupling increases the degradation rate of 8 times compared to photolysis and 2 times compared to sonolysis. There is a synergistic effect between the two modes of radiation, UV and U.S. leading to 82.04% degradation yield. An application of these combined processes on the treatment of a real pharmaceutical wastewater was examined.

Keywords: sonolysis, photocatalysis, combined process, antibiotic

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2904 Gamma Irradiation Effect on Structural and Optical Properties of Bismuth-Boro-Tellurite Glasses

Authors: Azuraida Amat, Halimah Mohamed Kamari, Che Azurahanim Che Abdullah, Ishak Mansor

Abstract:

The changes of the optical and structural properties of Bismuth-Boro-Tellurite glasses pre and post gamma irradiation were studied. Six glass samples, with different compositions [(TeO2)0.7 (B2O3)0.3]1-x (Bi2O3)x prepared by melt quenching method were irradiated with 25kGy gamma radiation at room temperature. The Fourier Transform Infrared Spectroscopy (FTIR) was used to explore the structural bonding in the prepared glass samples due to exposure, while UV-VIS Spectrophotometer was used to evaluate the changes in the optical properties before and after irradiation. Gamma irradiation causes a profound changes in the peak intensity as shown by FTIR spectra which is due to the breaking of the network bonding. Before gamma irradiation, the optical band gap, Eg value decreased from 2.44 eV to 2.15 eV with the addition of Bismuth content. The value kept decreasing (from 2.18 eV to 2.00 eV) following exposure to gamma radiation due to the increase of non-bridging oxygen (NBO) and the increase of defects in the glass. In conclusion, the glass with high content of Bi2O3 (0.30Bi) give the smallest Eg and show less changes in FTIR spectra after gamma irradiation, which indicate that this glass is more resistant to gamma radiation compared to other glasses.

Keywords: boro-tellurite, bismuth, gamma radiation, optical properties

Procedia PDF Downloads 427
2903 Non-Circular Carbon Fiber Reinforced Polymers Chainring Failure Analysis

Authors: A. Elmikaty, Z. Thanawarothon, L. Mezeix

Abstract:

This paper presents a finite element model to simulate the teeth failure of non-circular composite chainring. Model consists of the chainring and a part of the chain. To reduce the size of the model, only the first 11 rollers are simulated. In order to validate the model, it is firstly applied to a circular aluminum chainring and evolution of the stress in the teeth is compared with the literature. Then, effect of the non-circular shape is studied through three different loading positions. Strength of non-circular composite chainring and failure scenario is investigated. Moreover, two composite lay-ups are proposed to observe the influence of the stacking. Results show that composite material can be used but the lay-up has a large influence on the strength. Finally, loading position does not have influence on the first composite failure that always occurs in the first tooth.

Keywords: CFRP, composite failure, FEA, non-circular chainring

Procedia PDF Downloads 297
2902 An Exploratory Analysis of Brisbane's Commuter Travel Patterns Using Smart Card Data

Authors: Ming Wei

Abstract:

Over the past two decades, Location Based Service (LBS) data have been increasingly applied to urban and transportation studies due to their comprehensiveness and consistency. However, compared to other LBS data including mobile phone data, GPS and social networking platforms, smart card data collected from public transport users have arguably yet to be fully exploited in urban systems analysis. By using five weekdays of passenger travel transaction data taken from go card – Southeast Queensland’s transit smart card – this paper analyses the spatiotemporal distribution of passenger movement with regard to the land use patterns in Brisbane. Work and residential places for public transport commuters were identified after extracting journeys-to-work patterns. Our results show that the locations of the workplaces identified from the go card data and residential suburbs are largely consistent with those that were marked in the land use map. However, the intensity for some residential locations in terms of population or commuter densities do not match well between the map and those derived from the go card data. This indicates that the misalignment between residential areas and workplaces to a certain extent, shedding light on how enhancements to service management and infrastructure expansion might be undertaken.

Keywords: big data, smart card data, travel pattern, land use

Procedia PDF Downloads 287
2901 Length Weight Relationship and Relative Condition Factor of Atropus atropos (Bloch and Schneider, 1801) from Mangalore Coast, India

Authors: D. P. Rajesh, H. N. Anjanayappa, P. Nayana, S. Benakappa

Abstract:

The present study deals with length-weight relationship of Atropus atropos for which no information is available on this aspect from Mangalore coast. Therefore the present investigation was undertaken. Fish samples were collected from fish landing center (Mangalore) and fish market. The regression co-efficient of male was found to be lower than female. From this observation it may be opined that female gained more weight with increase in length compared to male. Data on seasonal variation in condition factor (Kn) showed that Kn values were more or less similar in both the sexes, indicating almost identical metabolic activity. Gonadal development and high feeding intensity are the factors which influenced the condition factor. The seasonal fluctuations in the relative condition factor of both the sexes could be attributed to the sexual cycle, food intake and environmental factors. From the present study, it can be inferred that the variation in the condition of Atropus atropos was due to feeding activity and gonadal maturity.

Keywords: Atropus atropos, length-weight relationship, Mangalore coast, relative condition factor, Kn

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2900 Design of Regular Communication Area for Infrared Electronic-Toll-Collection Systems

Authors: Wern-Yarng Shieh, Chao Qian, Bingnan Pei

Abstract:

A design of communication area for infrared electronic-toll-collection systems to provide an extended communication interval in the vehicle traveling direction and regular boundary between contiguous traffic lanes is proposed. By utilizing two typical low-cost commercial infrared LEDs with different half-intensity angles Φ1/2 = 22° and 10°, the radiation pattern of the emitter is designed to properly adjust the spatial distribution of the signal power. The aforementioned purpose can be achieved with an LED array in a three-piece structure with appropriate mounting angles. With this emitter, the influence of the mounting parameters, including the mounting height and mounting angles of the on-board unit and road-side unit, on the system performance in terms of the received signal strength and communication area are investigated. The results reveal that, for our emitter proposed in this paper, the ideal "long-and-narrow" characteristic of the communication area is very little affected by these mounting parameters. An optimum mounting configuration is also suggested.

Keywords: dedicated short-range communication (DSRC), electronic toll collection (ETC), infrared communication, intelligent transportation system (ITS), multilane free flow

Procedia PDF Downloads 337