Search results for: biodegradable characteristics

Authors: A. Naamane, M. Hasnaoui

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Numerical modeling of fluid flows, whether compressible or incompressible, laminar or turbulent presents a considerable contribution in the scientific and industrial fields. However, the development of an approximate model of a supersonic flow requires the introduction of specific and more precise techniques and methods. For this purpose, the object of this paper is modeling a supersonic flow of inviscid fluid around a dihedral airfoil. Based on the thin airfoils theory and the non-dimensional stationary Steichen equation of a two-dimensional supersonic flow in isentropic evolution, we obtained a solution for the downstream velocity potential of the oblique shock at the second order of relative thickness that characterizes a perturbation parameter. This result has been dealt with by the asymptotic analysis and characteristics method. In order to validate our model, the results are discussed in comparison with theoretical and experimental results. Indeed, firstly, the comparison of the results of our model has shown that they are quantitatively acceptable compared to the existing theoretical results. Finally, an experimental study was conducted using the AF300 supersonic wind tunnel. In this experiment, we have considered the incident upstream Mach number over a symmetrical dihedral airfoil wing. The comparison of the different Mach number downstream results of our model with those of the existing theoretical data (relative margin between 0.07% and 4%) and with experimental results (concordance for a deflection angle between 1° and 11°) support the validation of our model with accuracy.

Keywords: asymptotic modelling, dihedral airfoil, supersonic flow, supersonic wind tunnel

Procedia PDF Downloads 134

Authors: Yu Wen Wang, Shyh Ming Kuo, Hsia Ying Cheng, Yu Chiuan Wu

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Liver fibrosis is caused by the activation of hepatic stellate cells in the liver to secrete excessive and deposition of extracellular matrix. In recent years, many treatment strategies have been developed to reduce the activation of hepatic stellate cells and therefore to increase the decomposition of extracellular matrix. Bacopa monnieri, an herbaceous plant of the scrophulariaceae, containing saponins and glycosides, which with antioxidant, anti-inflammation, pain relief and free radical scavenging characteristics. This study was to evaluate the inhibition of hepatic stellate cell activity by Bacopa monnieri extract and its therapeutic potential in treating thioacetamide-induced liver fibrosis in rats. The results showed that the IC50 of Bacopa monnieri extract was 0.39 mg/mL. Bacopa monnieri extract could effectively reduce H2O2-induced hepatic stellate cells inflammation. In the TAA-induced liver fibrosis animal studies, albumin secretion recovered to normal level after treated with Bacopa monnieri extract for 2-w, and fibrosis related proteins, α-SMA and TGF-1levels decreased indicating the extract exerted therapeutic effect on the liver fibrosis. However, inflammatory factors TNF- obviously decreased after 4-w treatment. In summary, we could successfully extract the main component-Bacopaside I from the plant and acquired a potential therapy using this component in treating TAA-induced liver fibrosis in rat.

Keywords: anti-inflammatory, Bacopa monnieri, fibrosis, hepatic stellate cells, water extract

Procedia PDF Downloads 111

Authors: Liudmila A.Guzikova

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Being federative state Russia includes more than 80 subjects which are widely diverse by climatic conditions, demographic characteristics, cultural traditions, intensity of migration, economic development and investment attraction and other parameters. Now, in the regions of the country all forms of housing problem are present - housing mismatch to sanitary and hygienic standards, overcrowding, forced residence in financially burdensome housing, homelessness, -although the extent of these symptoms varies widely. Heterogeneity of regional conditions in combination with specifics of regional housing situation requires to concentrate the study of housing problem on the regional level. Traditionally housing market and mortgage are considered as the instruments of housing problem solving. The question arises how the housing market and mortgage market contribute to solving the housing problem in the regions of Russia. Though the purchase of dwelling in ownership should not be regarded as a universal method of the housing problem solving, the purchase of dwelling both by own funds or by use of mortgage can reduce the problem and enhance public satisfaction of living conditions. The aim of the study is to identify differences and similarities in the development of regional housing markets and mortgage lending in the regions of Russia and to evaluate their impact on the status of the housing problem. To achieve the aim of the study the methods of correlation and regression analysis are used. The data of federal statistics constitutes the information base of research. The results of the study contribute to better understanding of the interrelations in housing sphere and can be used to work out social and economic development programs in the regions.

Keywords: housing market, housing problem, mortgage, regional economy

Procedia PDF Downloads 377

Authors: Belkheir Noura, Rabah Kerfah, Boumehani Abdellah

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The influence of solidity variations on the aerodynamic performance of H type vertical axis wind turbine is studied in this paper. The wind turbine model used in this paper is the three-blade wind turbine with the symmetrical airfoil, NACA0021. The length of the chord is 0.265m. Numerical investigations were implemented for the different solidity by changing the radius and blade number. A two-dimensional model of the wind turbine is employed. The approach a Reynolds-Averaged Navier–Stokes equations, completed by the K- ώ SST turbulence model, is used. Motion mesh model capability of a computational fluid dynamics (CFD) solver is used. For each value of the solidity, the aerodynamics performances and the characteristics of the flow field are studied at several values of the tip speed ratio, λ = 0.5 to λ = 3, with an incoming wind speed of 8 m/s. The results show that increasing the number of blades will reduce the maximum value of the power coefficient of the wind turbine. Also, for the VAWT with a lower solidity can obtain the maximum Cp at a high tip speed ratio. The effects of changing the radius and blade number on aerodynamic performance are almost the same. Finally, for the validation, experimental data from the literature and computational results were compared. In conclusion, to study the influence of the solidity in the performances of the wind turbine is to provide the reference for the design of H type vertical axis wind turbines.

Keywords: wind energy, darrieus h type vertical axis wind turbine, computational fluid dynamic, solidity

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Authors: Muhammad Hassan, Kemal Celebi

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Developing a highly efficient electrochromic energy storage device with sufficient color fluctuation and significant electrochemical performance is highly desirable for practical energy-saving applications. Here, to achieve a highly stable material with a large electrochemical storage capacity, a W₁₈O₄₉ NW/Ti₃C₂Tₓ composite has been fabricated and deposited on a pre-assembled Ag and W₁₈O₄₉ NW conductive network by Langmuir-Blodgett technique. The resulting hybrid electrode composed of 15 layers of W₁₈O₄₉ NW/Ti₃C₂Tₓ exhibits an areal capacitance of 125 mF/cm², with a fast and reversible switching response. An optical modulation of 98.2% can be maintained at a current density of 5 mAcm⁻². Using this electrode, we fabricated a bifunctional symmetric electrochromic supercapacitor device having an energy density of 10.26 μWh/cm² and a power density of 0.605 mW/cm², with high capacity retention and full columbic efficiency over 4000 charge-discharge cycles. Meanwhile, the device displays remarkable electrochromic characteristics, including fast switching time (5 s for coloring and 7 s for bleaching) and a significant coloration efficiency of 116 cm²/C with good optical modulation stability. In addition, the device exhibits remarkable mechanical flexibility and fast switching while being stable over 100 bending cycles, which is promising for real-world applications.

Keywords: MXene, nanowires, supercapacitor, ion diffusion, electrochromic, coloration efficiency

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Authors: V. Hashim, P. N. Dileep

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Stent implantation is being seen as the most successful method to treat coronary artery diseases. Different types of stents are available in the market these days and the success of a stent implantation greatly depends on the proper selection of a suitable stent for a patient. Computer numerical simulation is the cost effective way to choose the compatible stent. Studies confirm that the design characteristics of stent do have great importance with regards to the pressure it can sustain, the maximum displacement it can produce, the developed stress concentration and so on. In this paper different designs of stent were analyzed together with balloon to optimize the stent and balloon system. Commercially available stent Palmaz-Schatz has been selected for analysis. Abaqus software is used to simulate the system. This work is the finite element analysis of the artery stent implant to find out the design factors affecting the stress and strain. The work consists of two phases. In the first phase, stress distribution of three models were compared - stent without balloon, stent with balloon of equal length and stent with balloon of extra length than stent. In second phase, three different design models of Palmaz-Schatz stent were compared by keeping the balloon length constant. The results obtained from analysis shows that, the design of the strut have strong effect on the stress distribution. A design with chamfered slots found better results. The length of the balloon also has influence on stress concentration of the stent. Increase in length of the balloon will reduce stress, but will increase dog boning effect.

Keywords: coronary stent, finite element analysis, restenosis, stress concentration

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Authors: Vilasinee Jintalikhitdee, Saowapa Phaithayawat

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The research on “The Way of Life of the Civil Servant Community under the Bureau of the Royal Household” aims to study 1) the way of life of the people who live in the civil servant community in Tha Wasukri, and 2) the model of community administration of civil servants under the Bureau of the Royal Household. This research is conducted qualitatively and quantitatively by collecting data from interviews, focus group discussion, participant and non-participant observation along with the data from the questionnaire based on age groups which include elder group, working age group and youth group. The result of the research shows that the origin of this community is related to the history during the Rama V’s reign. It has been a harbor for the king to boat in any royal ceremonies; this custom is still maintained until today. The status or position of person who serves the king in terms of working is often inherited from the bureau of the Royal Household based on his/her consanguinity and, hence, further receives the rights to live in the Tha Wasukri area. Therefore, this community has some special characteristics demonstrating the way of living influenced by the regulation of the Bureau of the Royal Household such as respecting elders and interdependence in which there is internal social organization with the practice of bureaucracy in going in and out the community. The person who has rights to live here must be friendly to everybody so that this community will be a safe place for lives and property. The administration based on the model of Bangkok for local administration was used as an external structure only, but the way of living still follows the practice of the Bureau of the Royal Household.

Keywords: way of life, community, Tha Wasukri, Bureau of the Royal Household

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Authors: Mary Esere, Mogbekeloluwa Fakokunde, Adetoun Idowu

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Background: Working in a military setting could elicit some amount of stressful doses into ones system because of the attendant peculiar characteristics found in the military environment. Thus, this study was carried out to find out the sources of occupational stress among teachers in various Command Secondary Schools within 2 Division of Nigerian Army. Method: The study employed a survey method. Simple random sampling technique was used to select the schools in the Division. A total of 200 respondents participated in the study. Sources of Teachers’ Occupational Stress Questionnaire (STOSQ) was administered to the respondents to collect relevant data. The t-test and Analysis of Variance (ANOVA) statistics were used to test the hypotheses. Findings: From the study, it was discovered that teachers in this setting do experience occupational stress. Their major sources of stress bother on issues relating to salaries and allowances and staff welfare concerns. The findings also revealed that there were no significant differences in the sources of occupational stress among the teachers in respect to gender and marital status. Discussion: Based on these findings, it was recommended that the Appropriate Superior Authority (ASA) should reconstitute the proscribed Armed Forces Schools Management Board (AFSMB) where issues, such as staff salaries and welfare concerns for teachers working in the schools under the three services (Army, Navy, Airforce) will always be addressed. This will go a long way in enhancing the psychological well-being of the teachers.

Keywords: Nigerian army, occupational stress, sources, teachers

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Authors: Haruna Abdu Usman, Bashir Usman Mohammed, Mohammed Umar Jamil

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Municipal solid waste management constitutes a serious problem bedeviling environmental protection agencies in many cities of developing countries. Most agencies do not collect the totality of the waste generated in their cities. This study presents the current solid waste management practices and problems in Bauchi metropolis, Bauchi state Nigeria. The general feature is characterized by inefficient, insufficient and irrational collection and improper disposal alternatives. The consequent environmental effects of these problems depict clogged city drains, uncollected heap of waste on road sides of residential areas, vacant plots and uncompleted buildings and highways. This contributes immensely to flooding in the city. The major challenges facing the state environmental protection agency includes; lack of collection and disposal points, technical and institutional arrangements, financial resources and general attitude of the serving public among others. The study suggested a comprehensive and integrated approach to the solid waste management which recognizes and incorporates the interventionist role of the state government, the private formal and informal waste management operators and the serving public.

Keywords: municipal solid waste, bauchi metropolitan area, environmental protection agency, solid waste management, waste disposal

Procedia PDF Downloads 743

Authors: Mahmoudi Marwa, Bahim Nadhem, Aydi Abdelwaheb, Issaoui Wissal, S. Najet

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This work represents a coupling between the geographic information system (GIS) and the multicriteria analysis aiming at the selection of an artificial recharge site by the treated wastewater for the Ariana governorate. On regional characteristics, bibliography and available data on artificial recharge, 13 constraints and 5 factors were hierarchically structured for the adequacy of an artificial recharge. The factors are subdivided into two main groups: environmental factors and economic factors. The adopted methodology allows a preliminary assessment of a recharge site, the weighted linear combination (WLC) and the analytical hierarchy process (AHP) in a GIS. The standardization of the criteria is carried out by the application of the different membership functions. The form and control points of the latter are defined by the consultation of the experts. The weighting of the selected criteria is allocated according to relative importance using the AHP methodology. The weighted linear combination (WLC) integrates the different criteria and factors to delineate the most suitable areas for artificial recharge site selection by treated wastewater. The results of this study showed three potential candidate sites that appear when environmental factors are more important than economic factors. These sites are ranked in descending order using the ELECTRE III method. Nevertheless, decision making for the selection of an artificial recharge site will depend on the decision makers in force.

Keywords: artificial recharge site, treated wastewater, analytical hierarchy process, ELECTRE III

Procedia PDF Downloads 166

Authors: Gubiani Rino, Nicola Zucchiatti, Da Broi Ugo, Bietresato Marco

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The problem of vibrations in agriculture is very important due to the different types of machinery used for the different types of soil in which work is carried out. One of the most commonly used machines is the tractor, where the phenomenon has been studied for a long time by measuring the whole body and placing the sensor on the seat. However, this measurement system does not take into account the characteristics of the drivers, such as their body index (BMI), their gender (male, female) or the muscle fatigue they are subjected to, which is highly dependent on their age for example. The aim of the research was therefore to place sensors not only on the seat but along the spinal column to check the transmission of vibration on drivers with different BMI on different tractors and at different travel speeds and of different genders. The test was also done using wearable sensors such as a dynamometer applied to the muscles, the data of which was correlated with the vibrations produced by the tractor. Initial data show that even on new tractors with pneumatic seats, the vibrations attenuate little and are still correlated with the roughness of the track travelled and the forward speed. Another important piece of data are the root-mean square values referred to 8 hours (A(8)x,y,z) and the maximum transient vibration values (MTVVx,y,z) and, the latter, the MTVVz values were problematic (limiting factor in most cases) and always aggravated by the speed. The MTVVx values can be lowered by having a tyre-pressure adjustment system, able to properly adjust the tire pressure according to the specific situation (ground, speed) in which a tractor is operating.

Keywords: fatigue, effect vibration on health, tractor driver vibrations, vibration, muscle skeleton disorders

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Authors: Narendra Kumar

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This study uses data from the ‘National Family Health Survey (NFHS-3) 2005-06’ to investigate the predictors of infant and child mortality among low economic households in East and Northeast region. The cross tabulation, life table survival estimates and Cox proportional hazard model techniques have been used to estimate the predictors of infant and child mortality. The life table survival estimates for infant and child mortality shows that infant mortality in female child is lower in comparison to male child but with child mortality, the rates are higher for female in comparison to male child and the Cox proportional hazard model also give highly significant in female in comparison to male child. The infant and child mortality rates among poor households highest in the Central region followed by North and Northeast region and the lowest in South region in comparison to all regions of India. Education of respondent has been found a significant characteristics in both analyzes, further birth interval, respondent occupation, caste/tribe and place of delivery has substantial impact on infant and child mortality among low economic households in East and Northeast region. Finally these findings specified that an increase in parents’ education, improve health care services and improve socioeconomic conditions of low economic households which should in turn raise infant and child survival and should decrease child mortality among low economic households in India.

Keywords: infant, child, mortality, socio-economic, India

Procedia PDF Downloads 307

Authors: Amira Abdelhafez, Rufus Brunt

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Geothermal energy in Egypt represents a significant untapped renewable resource that can reduce reliance on conventional power generation. Exploiting these geothermal resources depends on depth, temperature range, and geological characteristics. The intracontinental rift setting of the Gulf of Suez (GoS)-Red Sea rift is a favourable tectonic setting for convection-dominated geothermal plays. The geothermal gradient across the GoS ranges from 24.9 to 86.66 °C/km, with a heat flow of 31-127.2 mW/m². Surface expressions of convective heat loss emerge along the gulf flanks as hot springs (e.g., Hammam Faraun) accompanying deeper geothermal resources. These thermal anomalies are driven mainly by the local tectonic configuration. Characterizing the structural framework of major faults and their control on reservoir properties and subsurface hydrothermal fluid circulation is vital for geothermal applications in the gulf. The geothermal play systems of the GoS depend on structural and lithological properties that contribute to heat storage and vertical transport. Potential geothermal reservoirs include the Nubia sandstones, which, due to their thickness, continuity, and contact with hot basement rocks at a mean depth of 3 km, create an extensive reservoir for geothermal fluids. To develop these geothermal resources for energy production, defining the permeability anisotropy of the reservoir due to faults and facies variation is a crucial step in our study, particularly the evaluation of influence on thermal breakthrough and production rates.

Keywords: geothermal, October field, site specific study, reservoir modelling

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Authors: Mariam Azam, Sajjad Ur Rahman, Mukarram Bashir, Muhammad Tahir, Seemal Javaid, Jawad, Aoun Muhammad, Muhammad Zohaib, Hannan Khan

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Products of microbial origin are of great importance as they have proved their value in healthcare and nutrition, use of these microbial metabolites acquired from partially fermented soya hulls and wheat bran along with Saccharomyces cerevisiae (DL-22 S/N) substantiates to be a great source for an increase in the total milk production and quality yield.1×109 CFU/ml cells of Saccharomyces cerevisiae (DL-22 S/N) were further grown under in-vivo conditions for the assessment of quality milk production. Two groups with twelve cows, each having the same physical characteristics (Group A and Group B), were under study, Group A was daily fed with 12gm of biological metabolites and 22% protein-pelleted feed. On the other hand, the animals of Group B were provided with no metabolites in their feed. In thirty days of trial, improvement in the overall health, body score, milk protein, milk fat, yield, incidence rate of mastitis, ash, and solid not fat (SNF) was observed. The collected data showed that the average quality milk production was elevated up to 0.45 liter/h/d. However, a reduction in the milk fats up to 0.45% and uplift in the SNF value up to 0.53% of cow milk was also observed. At the same time, the incidence rate of mastitis recorded for the animals under trial was reduced to half, and improved non specific immunity was reported.

Keywords: microbial metabolites, post-biotics, animal supplements, animal nutrition, proteins, animal production, fermentation

Procedia PDF Downloads 101

Authors: Kavindan Balakrishnan

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Root cause Identification of the Vibration phenomenon in a feedwater pumping station was the main objective of this research. First, the mode shapes of the pumping structure were investigated using numerical and analytical methods. Then the flow pressure and streamline distribution in the pump sump were examined using C.F.D. simulation, which was hypothesized can be a cause of vibration in the pumping station. As the problem specification of this research states, the vibration phenomenon in the pumping station, with four parallel pumps operating at the same time and heavy vibration recorded even after several maintenance steps. They also specified that a relatively large amplitude of vibration exited by pumps 1 and 4 while others remain normal. As a result, the focus of this research was on determining the cause of such a mode of vibration in the pump station with the assistance of Finite Element Analysis tools and Analytical methods. Major outcomes were observed in structural behavior which is favorable to the vibration pattern phenomenon in the pumping structure as a result of this research. Behaviors of the numerical and analytical models of the pump structure have similar characteristics in their mode shapes, particularly in their 2nd mode shape, which is considerably related to the exact cause of the research problem statement. Since this study reveals several possible points of flow visualization in the pump sump model that can be a favorable cause of vibration in the system, there is more room for improved investigation on flow conditions relating to pump vibrations.

Keywords: vibration, simulation, analysis, Ansys, Matlab, mode shapes, pressure distribution, structure

Procedia PDF Downloads 124

Authors: Kevin Molina, Daniel Ortega, Manuel Martinez, Andres Gonzalez-Estrada, William Pinto

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Due to the increasing environmental impact, the wind energy is getting strong. This research studied the relationship between the power produced by a horizontal axis wind turbine (HAWT) and the aerodynamic profiles used for its construction. The analysis is studied using the Computational Fluid Dynamic (CFD), presenting the parallel between the energy generated by a turbine designed with selected profiles and another one optimized. For the study, a selection process was carried out from profile NACA 6 digits recommended by the National Renewable Energy Laboratory (NREL) for the construction of this type of turbines. The selection was taken into account different characteristics of the wind (speed and density) and the profiles (aerodynamic coefficients Cl and Cd to different Reynolds and incidence angles). From the selected profiles, was carried out a sensitivity analysis optimization process between its geometry and the aerodynamic forces that are induced on it. The 3D model of the turbines was realized using the Blade Element Momentum method (BEM) and both profiles. The flow fields on the turbines were simulated, obtaining the forces induced on the blade, the torques produced and an increase of 3% in power due to the optimized profiles. Therefore, the results show that the sensitivity analysis optimization process can assist to increment the wind turbine power.

Keywords: blade element momentum, blade, fluid structure interaction, horizontal axis wind turbine, profile design

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Authors: Liubov Magerramova, Eugene Kratt, Pavel Presniakov

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A detailed analysis has been performed for several schemes of Gas Turbine Wheels production based on additive and powder technologies including metal, ceramic, and stereolithography 3-D printing. During the process of development and debugging of gas turbine engine components, different versions of these components must be manufactured and tested. Cooled blades of the turbine are among of these components. They are usually produced by traditional casting methods. This method requires long and costly design and manufacture of casting molds. Moreover, traditional manufacturing methods limit the design possibilities of complex critical parts of engine, so capabilities of Powder Metallurgy Techniques (PMT) were analyzed to manufacture the turbine wheel with air-cooled blades. PMT dramatically reduce time needed for such production and allow creating new complex design solutions aimed at improving the technical characteristics of the engine: improving fuel efficiency and environmental performance, increasing reliability, and reducing weight. To accelerate and simplify the blades manufacturing process, several options based on additive technologies were used. The options were implemented in the form of various casting equipment for the manufacturing of blades. Methods of powder metallurgy were applied for connecting the blades with the disc. The optimal production scheme and a set of technologies for the manufacturing of blades and turbine wheel and other parts of the engine can be selected on the basis of the options considered.

Keywords: additive technologies, gas turbine engine, powder technology, turbine wheel

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Authors: Mustafa Yildiz, Ali Sinan Soganci

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Pumice soils are countered in many projects such as transportation roads, channels and residential units throughout the World. The pumice deposits are characterized by the vesicular nature of their particles. When the pumice soils are evaluated considering the geotechnical viewpoint, they differ from silica sands in terms of physical and engineering characteristics. These differences are low grain strength, high friction angle, void ratio and compressibility. At stresses greater than a few hundred kPa, the stress-strain-strength behaviour of these soils is determined by particle crushing. Particle crushing leads to changes in the density and reduction in the components of shear stress due to expansion. In this study, the bearing capacity and behaviour of granular pumice soils compared to sand-gravels were investigated by laboratory model tests. Firstly the geotechnical properties of granular pumice soils were determined; then, the behaviour of pumice soils with an equivalent diameter of sand and gravel soils were investigated by model rectangular and circular foundation types and were compared with each other. For this purpose, basic types of model footing (15*15 cm, 20*20 cm, Φ=15 cm and Φ=20 cm) have been selected. When the experimental results of model bearing capacity are analyzed, the values of sand and gravel bearing capacity tests were found to be 1.0-1.5 times higher than the bearing capacity of pumice the same size. This fact has shown that sand and gravel have a higher bearing capacity than pumice of the similar particle sizes.

Keywords: pumice soils, laboratory model tests, bearing capacity, laboratory model tests, Nevşehir

Procedia PDF Downloads 214

Authors: Volkan Ayik

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Loosening as a result of torque loss in bolted joints is one of the most encountered problems resulting in loss of connection between parts. The main reason for this is the dynamic loads to which the joints are subjected while the vehicle is moving. In particular, vibration-induced loads can loosen the joints in any size and geometry. The aim of this study is to study an improved method due to road-induced vibration in heavy commercial vehicles for estimating the vibration performance of bolted joints of the components connected to the chassis, before conducting prototype level vehicle structural strength tests on a proving ground. The frequency and displacements caused by the road conditions-induced vibration loads have been determined for the parts connected to the chassis, and various experimental design scenarios have been formed by matching specific components and vibration behaviors. In the studies, the performance of the torque, washer, test displacement, and test frequency parameters were observed by maintaining the connection characteristics on the vehicle, and the sensitivity ratios for these variables were calculated. As a result of these experimental design findings, tests performed on a developed device based on Junker’s vibration device and proving ground conditions versus test correlation levels were found.

Keywords: bolted joints, junker’s test, loosening failure, torque loss

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Authors: Emely J. Escala, Lolito C. Bestil

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An experiment was conducted to assess the potential of jackfruit by-product concentrate (JBC) in combination with two types of protein sources, soybean meal (SBM) and liquid acid whey (LAW), given at two different ratios as supplement for growing kids fed a basal diet of 70:30 napier grass (Pennisetum purpureum) and kakawate (Gliricidia sepium) soilage ratio. The experiment was set-up in randomized complete block design (RCBD) with sex-age combination as basis for blocking, with the following dietary treatments: T1 = 0.50:0.50% BW, DM basis, JBC:SBM, T2 = 0.75:0.25% BW JBC:SBM, T3 = 0.50:0.50% BW, DM basis, JBC:LAW, and T4 = 0.75:0.25% BW JBC:LAW. Analysis of JBC showed high contents of crude fiber with medium levels of crude protein and nitrogen-free extract, appearing to be fitting for ruminants and a potential energy source. Results showed significantly higher voluntary dry matter intake (VDMI), cumulative weight gain (CWG), and average daily gain (ADG) of growing goats supplemented with JBC in combination with SBM than with LAW. The amount of JBC can range from 0.50% to 0.75% BW with SBM making up the difference, but a JBC:SBM ratio of 0.75:0.25% BW, DM basis, is best in promoting highest voluntary dry matter intake and is, therefore, highly recommended in the light of savings in feed cost. A long-term study on the effects of JBC supplementation on meat qualities of growing kids (aroma, marbling characteristics and taste) is also recommended.

Keywords: jackfruit by-product concentrate, liquid acid whey, soybean meal, grower kids

Procedia PDF Downloads 198

Authors: Adrian Ionut Nicoara, Denisa Ionela Ene, Alina Maria Holban, Cristina Busuioc

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At present, the development of materials with biomedical applications is a domain of interest that will produce a full series of benefits in engineering and medicine. In this sense, it is required to use a natural material, and this paper is focused on the development of a composite material based on bacterial cellulose – hydroxyapatite and silver nanoparticles with applications in hard tissue. Bacterial cellulose own features like biocompatibility, non-toxicity character and flexibility. Moreover, the bacterial cellulose can be conjugated with different forms of active silver to possess antimicrobial activity. Hydroxyapatite is well known that can mimic at a significant level the activity of the initial bone. The material was synthesized by using an ultrasound probe and finally characterized by several methods. Thereby, the morphological properties were analyzed by using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Because the synthesized material has medical application in restore the tissue and to fight against microbial invasion, the samples were tested from the biological point of view by evaluating the biodegradability in phosphate-buffered saline (PBS) and simulated body fluid (SBF) and moreover the antimicrobial effect was performed on Gram-positive bacterium Staphylococcus aureus, Gram-negative bacterium Escherichia coli, and fungi Candida albicans. The results reveal that the obtained material has specific characteristics for bone regeneration.

Keywords: bacterial cellulose, biomaterials, hydroxyapatite, scaffolds materials

Procedia PDF Downloads 133

Authors: Akbar Darouie, Mamak Joulaie

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In regard of phonological skills development importance and its influence on other aspects of language, this study has been performed. Determination of some phonological indexes in children with hearing impairment and comparison with hearing children was the objective. A sample of convenience was selected from a rehabilitation center and a kindergarten in Karaj, Iran. Participants consisted of 12 hearing impaired and 12 hearing children (age range: 5 years and 6 months to 6 years and 6 months old). Hearing impaired children suffered from severe to profound hearing loss while three of them were cochlear implanted and the others were wearing hearing aids. Conversational speech of these children was recorded and 50 first utterances were selected to analyze. Percentage of consonant correct (PCC) and vowel correct (PVC), initial and final consonant omission error, cluster consonant omission error and syllabic structure variety were compared in two groups. Data were analyzed with t test (version 16th SPSS). Comparison between PCC and PVC averages in two groups showed a significant difference (P< 0/01). There was a significant difference about final consonant emission error (P<0/001) and initial consonant emission error (P<0/01) too. Also, the differences between two groups on cluster consonant omission were significant (P<0/001). Therefore, some changes were seen in syllabic structures in children with hearing impairment compared to typical group. This study demonstrates some phonological differences in Farsi language between two groups of children. Therefore, it seems, in clinical practices we must notice this issue.

Keywords: hearing impairment, phonology, vowel, consonant

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Authors: Xiao Zhou, Kazuhiro Imai, Xiaoxuan Liu

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Badminton is one type of racket sports that requires repetitive overhead motion, with the shoulder in abduction/external rotation and requires players to perform jumps, lunges, and quick directional changes. These characteristics could be stressful for body regions that may cause badminton injuries. Regarding racket players including badminton players, there have not been any studies that have utilized medical check-up to evaluate epidemiology and mechanism of injuries. In addition, epidemiology of badminton injury in school age badminton players is unknown. The first purpose of this study was to investigate the badminton injuries, physical fitness parameters, and intensity of shoulder pain using medical check-up so that the mechanisms of shoulder injuries might be revealed. The second purpose of this study was to survey the distribution of badminton injuries in elementary school age players so that injury prevention can be implemented as early as possible. The results of this study revealed that shoulder pain occurred in all players, and present shoulder pain players had smaller weight, greater shoulder external rotation (ER) gain, significantly thinner circumference of upper limbs and greater trunk extension. Identifying players with specific of these factors may enhance the prevention of badminton injury. This study also shows that there are high incidences of knee, ankle, plantar, and shoulder injury or pain in elementary school age badminton players. Injury prevention program might be implemented for elementary school age players.

Keywords: badminton injury, epidemiology, medical check-up, school age players

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Authors: Hossein Mottaghi T., Amir R. Masoodi

Abstract:

This study presents a finite curved element for analyzing the static behavior of curved beams within the elastic range. The objective is to enhance accuracy while reducing the number of elements by incorporating first-order shear deformations of Timoshenko beams. Initially, finite element formulations are developed by considering polynomial initial functions for axial, shear, and rotational deformations for a three-node element. Subsequently, nodal interpolation functions for this element are derived, followed by the construction of the element stiffness matrix. To enable the utilization of the stiffness matrix in the static analysis of curved beams, the constructed matrix in the local coordinates of the element is transformed to the global coordinate system using the rotation matrix. A numerical benchmark example is investigated to assess the accuracy and effectiveness of this method. Moreover, the influence of spring stiffness on the rotation of the endpoint of a clamped beam is examined by substituting each support reaction of the beam with a spring. In the parametric study, the effect of the central angle of the beam on the rotation of the beam's endpoint in a cantilever beam under a concentrated load is examined. This research encompasses various mechanical, geometrical, and boundary configurations to evaluate the static characteristics of curved beams, thus providing valuable insights for their analysis and examination.

Keywords: curved beam, finite element method, first-order shear deformation theory, elastic support

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Authors: Jiang Xu, Daoping Wang, Qun Li, Yinghong Pan

Abstract:

2,4-Epibrassinolide (EBR), which is a kind of plant hormone Brassinosteroids (BRs), is widely studied and applied in the global scale but the proteomic characteristics of EBR alleviating low temperature stress in rice seedling leaves are still not clear. In this study, seeding rice of Nipponbare were treated with EBR and distilled water, then stressed at 4℃ or 26 ℃, and analyzed by mass spectrometry analysis, verified by parallel reaction monitoring technique (PRM). The results showed that 5778 proteins were identified in total and 4834 proteins were identified with quantitative information. Among them, 401 up-regulated and 220 down-regulated proteins may be related to EBR alleviating low temperature stress in rice seedling leaves. The molecular functions of most of up-regulated proteins are RNA binding and hydrolase activity and are mainly enriched in the pathways of carbon metabolism, folic acid synthesis, and amino acid biosynthesis. The down-regulated proteins are mainly related to catalytic activity and oxidoreductase activity and are mainly enriched in the pathways of limonene and pinene degradation, riboflavin metabolism, porphyrin and chlorophyll metabolism, and other metabolic pathways. PRM validation and literature analysis showed that NADP-malic acidase, peroxidase, 3-phosphoglycerate dehydrogenase, enolase, glyceraldehyde-3- phosphate dehydrogenase and pyruvate kinase are closely related to the effect of EBR on low temperature stress. These results also suggested that BRs could relieve the effect of low temperature stress on rice seed germination in many ways.

Keywords: 2, 4-Epibrassinolid, low temperature stress, proteomic analysis, rice

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Authors: Chaitanya R. Mali, V. Vinod, Ashwin W. Patwardhan

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Design of long vertical steam generator (SG) tubes in nuclear power plant involves an understanding of different aspects of flow boiling phenomenon such as flow instabilities, flow regimes, dry out, critical heat flux, pressure drop, etc. The knowledge of the prediction of local thermal hydraulic characteristics is necessary to understand these aspects. For this purpose, the methodology has been developed which covers all the flow boiling regimes to model full range flow boiling phenomenon. In this methodology, the vertical tube is divided into four sections based on vapor fraction value at the end of each section. Different modeling strategies have been applied to the different sections of the vertical tube. Computational fluid dynamics simulations have been performed on a vertical SG tube of 0.0126 m inner diameter and 23 m length. The thermal hydraulic parameters such as vapor fraction, liquid temperature, heat transfer coefficient, pressure drop, heat flux distribution have been analyzed for different designed heat duties (1.1 MW (20%) to 3.3 MW (60%)) and flow conditions (10 % to 80 %). The sensitivity of different boiling parameters such as bubble departure diameter, nucleation site density, bubble departure frequency on the thermal hydraulic parameters was also studied. Flow instability has been observed at 20 % designed heat duty and 20 % flow conditions.

Keywords: thermal hydraulics, boiling, vapor fraction, sensitivity

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Authors: Yveta Pohnětalová, Veronika Nováková, Lucie Hrašová

Abstract:

The paper presents the results of research in which we were looking for common characteristics of the family environment of students alternative and innovative education systems. Topicality comes from the fact that nowadays in the Czech Republic there are several civic and parental initiatives held with the aim to establish schools for their children. The goal of our research was to reveal key aspects of these families and to identify their common indicators. Among other things, we were interested what reasons lead parents to decide to enroll their child into different education than standard (common). The survey was qualitative and there were eighteen respondents of parents of alternative schools´ pupils. The reason to implement qualitative design was the opportunity to gain deeper insight into the essence of phenomena and to obtain detailed information, which would become the basis for subsequent quantitative research. There have been semi structured interviews done with the respondents which had been recorded and transcribed. By an analysis of gained data (categorization and by coding), we found out that common indicator of our respondents is higher education and higher economic level. This issue should be at the forefront of the researches because there is lack of analysis which would provide a comparison of common and alternative schools in the Czech Republic especially with regard to quality of education. Based on results, we consider questions whether approaches of these parents towards standard education come from their own experience or from the lack of knowledge of current goals and objectives of education policy of the Czech Republic.

Keywords: alternative schools, family environment, quality of education, parents´ approach

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Authors: Suk Kyoon Song, Myung-Rae Cho

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Purpose: Paralytic ileus occurs in up to 18% of patients with pelvic bone fractures. The aim of this study is to determine if massive bleeding requiring arterial angioembolization is related to the duration of ileus in patients with traumatic pelvic ring injuries. Methods: This retrospective study included 25 patients who underwent arterial angioembolization for traumatic pelvic ring injuries. Data were collected from prospectively maintained databases of two independent hospitals. Results: Demographic characteristics (such as age, sex, body mass index, and Charlson Comorbidity Index), cause of trauma, and severity of pelvic injuries were similar in the non-prolonged and prolonged ileus groups. As expected, the prolonged ileus group had a significantly longer duration of ileus than the non-prolonged ileus group (8.0 ± 4.2 days vs. 1.2 ± 0.4 days, respectively, P < 0.001). The mortality rate was higher in the prolonged ileus group (20% vs. 0%), but it was not significantly different (P = 0.13). Interestingly, the prolonged ileus group received significantly higher amounts of packed red blood cell (PRBC) transfusions (6.1 ± 2.1 units vs. 3.8 ± 2.5 units; P = 0.02). The amount of PRBC transfusions was associated with a greater risk of prolonged ileus development (P = 0.03, OR = 2.04, 95% CI = 1.08-3.88). Conclusion: This study supports the idea that the duration of the ileus is related to the amount of bleeding caused by the traumatic pelvic ring injury. In order to prevent further complications, conservative treatments of the ileus should be considered.

Keywords: pelvic ring injury, bleeding, ileus, arterial angioembolization

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Authors: Taehyun Kim, Hyunjoo Park, Taehyun Kim

Abstract:

Public deliberation committee on Shin-Gori Nuclear Reactors No. 5 & 6 in South Korea recently suggested policy recommendation in July 2017 including complementary measures for resumption of construction: 1) nuclear power generation reduction, 2) expansion of investment to increase proportion of renewable energy, 3) repositories of spent nuclear fuel. Even when constructing eco-friendly renewable energy facilities such as solar and wind power plants, local residents are opposed to construction of these facilities due to environmental pollution and health impacts. In order to transform eco-friendly energy, it is necessary to convert nuclear energy into renewable energy and to take measures to increase the acceptance of residents through the participation of citizens. Therefore, this study aims to compare the factors of local acceptance of renewable energy facilities and spent nuclear fuel repositories through literature review and in-depth interview. The results show that environmental and economic concerns, risk perceptions, sociality, demographic characteristics and subjective recognition types affect the local acceptance for spent nuclear fuel repository. The factors of local acceptance for renewable energy facilities are partially coincide with those for spent nuclear fuel repository. The results of this study will contribute to improving residents' acceptance and reducing conflicts when determining the location of facilities in the future.

Keywords: local acceptance, renewable energy facility, spent nuclear fuel repository, interview

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Authors: Suchitra Sivakumar, Hajime Shingyouchi, Toshinori Okajima, Kyohei Yamaguchi, Jin Kusaka

Abstract:

The progressing need for powertrain electrification calls for more accurate and reliable simulation models. A battery pack serves as the most vital component for energy storage in an electrified powertrain. Hybrid electric vehicles (HEV) do not behave the same way as they age, and there are several environmental factors that account for the degradation of the battery on a system level. Therefore, in this work, a battery model was proposed to study the state of charge (SOC) variation and the internal dynamic changes that contribute to aging and performance degradation in HEV batteries. An equivalent circuit battery model (ECM) is built using MATLAB Simulink to investigate the output characteristics of the lithium-ion battery. The ECM comprises of circuit elements like a voltage source, a series resistor and a parallel RC network connected in series. A parameter estimation study is conducted on the ECM to study the dependencies of the circuit elements with the state of charge (SOC) and the terminal voltage of the battery. The battery model is extended to simulate the temperature dependence of the individual battery cell and the battery pack with the environment. The temperature dependence model accounts for the heat loss due to internal resistance build up in the battery pack during charging, discharging, and due to atmospheric temperature. The model was validated for a lithium-ion battery pack with an independent drive cycle showing a voltage accuracy of 4% and SOC accuracy of about 2%.

Keywords: battery model, hybrid electric vehicle, lithium-ion battery, thermal model

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