Search results for: raised intraocular pressure
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4704

Search results for: raised intraocular pressure

2244 Social Infrastracture the Case of Education in Ethiopia

Authors: Tekalign Gidi Kure

Abstract:

This paper addresses a range of serious problems involving higher education in Ethiopia. In spite of increased enrollment in higher education, educational quality is deteriorating afterwards. Thus, this paper tried to assess the role of social infrastructure in education for economic development of the country and examined major critical problems in higher education of Ethiopia such as higher education finance, curriculum development, and instructor’s career development. Primarily the paper discusses the fundamental contributions of social infrastructure in higher education to economic development; namely development of human capital, improved health, life expectancy, increased productivity, and personal saving, then, the paper examines critically higher education in three regimes of Ethiopia (Emperor Regime, Derg Regime and EPDRF/current government). Thus, four main questions were raised during this research: "What are the antecedents of Ethiopia Higher Education System under three regimes?", " what are the current and emerging higher educational needs in Ethiopia economic development?", " what are the role of private sector in addressing the gaps in the higher education of the country and its adverse effect on quality issues? ", and "what improvements are needed in higher education system of Ethiopia?". Documents from Ministry of Education in Ethiopia, National Statistical Abstracts, and Reports from the World Bank and other recognized institutions were used in addition to recent empirical researches conducted in the country. In doing so, care had been taken to reduce prejudiced reports by involving different reports from multiple sources. The paper concludes that during emperor system higher education enrollment was among the very lowest in the world, therefore, the skilled human resource available to guide development were little, but the cost was very high. During the Derg regime where an ideological change in the system penetrated into higher education resulted with the lack of a large amount of resources to support higher education; the war inside and outside the country diverts resources from the sector. The main purpose of this paper is not only to discuss the problems and issues of higher education in the past, but it also investigates the influence that the current expansion of higher education has on the finance, staff, and other resources for the quality of education. The paper concludes that higher education in Ethiopia are financed by government, outdated curriculum and lagging behind the standard regarding qualified staff. Finally, it provided inevitable solutions if the country wants to gain well record in quality of education as well.

Keywords: social infrastructure, higher education, ethiopia, education quality

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2243 The Utilization of Recycled Construction and Demolition Waste Aggregate in Asphaltic Concrete

Authors: Inas Kamel, Noor Z. Habib

Abstract:

Utilizing construction and demolition wastes in hotmix asphalt (HMA) pavement construction can reduce the adverse environmental effect of its inadequate disposal and reduce the pressure of extracting and processing mineral aggregates (MA). This study aims to examine the viability of replacing MA by recycled construction and demolition waste aggregates (RCDWA) in the wearing course of asphaltic concrete (AC) pavements without compromising its loadbearing capacity. The Marshall Method was used to evaluate the performance of AC wearing course specimens by replacing MA by 10%, 20% and 30% RCDWA. Grade 60/70 bitumen was used in the range 3.0-5.5%, with 05% increments, to generate the optimum bitumen content (OBC). From the volumetric analysis and test property curves, the mixture containing 20% RCDWA was chosen as the preferred mix at 5.1% OBC. It possessed a 10% increase in Marshall Stability compared to the reference specimen, containing 100% MA, and a 6% increase in Marshall flow.

Keywords: aggregate, asphaltic concrete, Marshall method, optimum bitumen content, recycled construction and demolition waste

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2242 A Mixed Thought Pattern and the Question of Justification: A Feminist Project

Authors: Angana Chatterjee

Abstract:

The feminist scholars point out the various problematic issues in the traditional mainstream western thought and theories. The thought practices behind the discriminatory and oppressive social practices are based on concepts that play a pivotal role in theorisation. Therefore, many feminist philosophers take up reformation or reconceptualisation projects. Such projects have bearings on various aspects of philosophical thought, namely, ontology, epistemology, logic, ethics, social, political thought, and so on. In tune with this spirit, the present paper suggests a well-established thought pattern which is not western but has got the potential to deal with the problems of mainstream western thought culture that are identified by the feminist critics. The Indian thought pattern is theorised in the domain of Indian logic, which is a study of inference patterns. As, in the Indian context, the inference is considered as a source of knowledge, certain epistemological questions are linked with the discussion of inference. One of the key epistemological issues is one regarding justification. The study about the nature of derivation of knowledge from available evidence, and the nature of the evidence itself, are integral parts of the discipline called Indian logic. But if we contrast the western tradition of thought with the Indian one, we can find that the Indian logic has got some peculiar features which may be shown to deal with the problems identified by the feminist scholars in western thought culture more plausibly. The tradition of western logic, starting from Aristotle, has been maintaining sharp differences between two forms of reasoning, namely, deductive and inductive. These two different forms of reasoning have been theorised and dealt with separately within the domain of the study called ‘logic.’ There are various philosophical problems that are raised around concepts and issues regarding both deductive and inductive reasoning. Indian logic does not distinguish between deduction and induction as thought patterns, but their distinction is very usual to make in the western tradition. Though there can be found various interpretations about this peculiarity of Indian thought pattern, these mixed patterns were actually very close to the cross-cultural pattern in which human beings would tend to argue or infer from the available data or evidence. The feminist theories can successfully operate in the domain of lived experience if they make use of such a mixed pattern of reasoning or inference. By offering sound inferential knowledge on contextual evidences, the Indian thought pattern is potent to serve the feminist purposes in a meaningful way.

Keywords: feminist thought, Indian logic, inference, justification, mixed thought pattern

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2241 Investigation of Slope Stability in Gravel Soils in Unsaturated State

Authors: Seyyed Abolhasan Naeini, Ehsan Azini

Abstract:

In this paper, we consider the stability of a slope of 10 meters in silty gravel soils with modeling in the Geostudio Software.  we intend to use the parameters of the volumetric water content and suction dependent permeability and provides relationships and graphs using the parameters obtained from gradation tests and Atterberg’s limits. Also, different conditions of the soil will be investigated, including: checking the factor of safety and deformation rates and pore water pressure in drained, non-drained and unsaturated conditions, as well as the effect of reducing the water level on other parameters. For this purpose, it is assumed that the groundwater level is at a depth of 2 meters from the ground.  Then, with decreasing water level, the safety factor of slope stability was investigated and it was observed that with decreasing water level, the safety factor increased.

Keywords: slope stability analysis, factor of safety, matric suction, unsaturated silty gravel soil

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2240 Investigation of Hydrate Formation of Associated Petroleum Gas from Promoter Solutions for the Purpose of Utilization and Reduction of Its Burning

Authors: M. E. Semenov, U. Zh. Mirzakimov, A. S. Stoporev, R. S. Pavelev, M. A. Varfolomeev

Abstract:

Gas hydrates are host-guest compounds. Guest molecules can be low molecular weight components of associated petroleum gas (C1-C4 hydrocarbons), carbon dioxide, hydrogen sulfide, and nitrogen. Gas hydrates have a number of unique properties that make them interesting from a technological point of view, for example, for storing hydrocarbon gases in solid form under moderate thermobaric conditions. Currently, the possibility of storing and transporting hydrocarbon gases in the form of solid hydrate is being actively explored throughout the world. The hydrate form of gas has a number of advantages, including a significant gas content in the hydrate, relative safety and environmental friendliness of the process. Recently, new developments have been proposed that seek to reduce the number of steps to obtain the finished hydrate, for example, using a pressing device/screw inside the reactor. However, the energy consumption required for the hydrate formation process remains a challenge. Thus, the goal of the current work is to study the patterns and mechanisms of the hydrate formation process using small additions of hydrate formation promoters under static conditions. The study of these aspects will help solve the problem of accelerated production of gas hydrates with minimal energy consumption. New compounds have been developed at Kazan Federal University that can accelerate the formation of methane hydrate with a small amount of promoter in water, not exceeding 0.1% by weight. These promoters were synthesized based on available natural compounds and showed high efficiency in accelerating the growth of methane hydrate. To test the influence of promoters on the process of hydrate formation, standard experiments are carried out under dynamic conditions with stirring. During such experiments, the time at which hydrate formation begins (induction period), the temperature at which formation begins (supercooling), the rate of hydrate formation, and the degree of conversion of water to hydrate are assessed. This approach helps to determine the most effective compound in comparative experiments with different promoters and select their optimal concentration. These experimental studies made it possible to study the features of the formation of associated petroleum gas hydrate from promoter solutions under static conditions. Phase transformations were studied using high-pressure micro-differential scanning calorimetry under various experimental conditions. Visual studies of the growth mode of methane hydrate depending on the type of promoter were also carried out. The work is an extension of the methodology for studying the effect of promoters on the process of associated petroleum gas hydrate formation in order to identify new ways to accelerate the formation of gas hydrates without the use of mixing. This work presents the results of a study of the process of associated petroleum gas hydrate formation using high-pressure differential scanning micro-calorimetry, visual investigation, gas chromatography, autoclaves study, and stability data. It was found that the synthesized compounds multiply the conversion of water into hydrate under static conditions up to 96% due to a change in the growth mechanism of associated petroleum gas hydrate.

Keywords: gas hydrate, gas storage, promotor, associated petroleum gas

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2239 Effect of Accelerated Ions Interacted with Al Targets Using Plasma Focus Device

Authors: Morteza Habibi, Reza Amrollahi

Abstract:

The Aluminum made targets were placed at the central part of a Fillipov type (90KJ) plasma focus cathode. These targets were exposed to perpendicular dense plasma stream incidence. Melt layer erosion by melt motion, surface smoothing, and bubble formation were some of different effects caused by diverse working conditions. Micro hardness of surface layer tends to decrease particularly in the central region of the sample where destruction is more intense. The most pronouced melt motion is registered in the region of the maximum gradient of pressure and the etching of aluminium surface is noticeable in the central part of target. The crater with a maximum depth of 200µm, and the diameter of about 8.5mm is observed close to the mountains. Adding Krypton admixture to the Deuterium gas lead to collapsing bubbles and greater surface damage.

Keywords: fillipov type plasma focus, al target interaction, bubbling effect, melt layer motion, surface smoothing

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2238 Numerical Investigation of Heat Transfer Characteristics of Different Rib Shapes in a Gas Turbine Blade

Authors: Naik Nithesh, Andre Rozek

Abstract:

The heat transfer and friction loss performances of a single rib-roughened rectangular cooling channel having four novel rib shapes were evaluated through numerical investigation using Ansys CFX. The investigation was conducted on a rectangular channel of aspect ratio (AR) = 4:1 with rib height to hydraulic diameter ratio (e/Dh) of 0.1 and rib pitch to height ratio (e/P) of 10 at Re = 30,000. The computations were performed by solving the RANS equation using k-ε turbulence model. Fluid flow simulation results of stationery case for different configuration are presented in terms of thermal performance parameter, Nusselt number and friction factor. These parameters indicate that a particular configuration of novel shaped ribs provides better heat transfer characteristics over the conventional 45° ribs. The numerical investigation undertaken in this study indicates an increase in overall efficiency of gas turbine due to increased thermal performance parameter, heat transfer co-efficient and less pumping pressure.

Keywords: gas turbine, rib shapes, nusselt number, thermal performance parameter

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2237 Research on Spatial Pattern and Spatial Structure of Human Settlement from the View of Spatial Anthropology – A Case Study of the Settlement in Sizhai Village, City of Zhuji, Zhejiang Province, China

Authors: Ni Zhenyu

Abstract:

A human settlement is defined as the social activities, social relationships and lifestyles generated within a certain territory, which is also relatively independent territorial living space and domain composed of common people. Along with the advancement of technology and the development of society, the idea, presented in traditional research, that human settlements are deemed as substantial organic integrity with strong autonomy, are more often challenged nowadays. Spatial form of human settlements is one of the most outstanding external expressions with its subjectivity and autonomy, nevertheless, the projections of social, economic activities on certain territories are even more significant. What exactly is the relationship between human beings and the spatial form of the settlements where they live in? a question worth thinking over has been raised, that if a new view, a spatial anthropological one , can be constructed to review and respond to spatial form of human settlements based on research theories and methods of cultural anthropology within the profession of architecture. This article interprets how the typical spatial form of human settlements in the basin area of Bac Giang Province is formed under the collective impacts of local social order, land use condition, topographic features, and social contracts. A particular case of the settlement in Sizhai Village, City of Zhuji, Zhejiang Province is chosen to study for research purpose. Spatial form of human settlements are interpreted as a modeled integrity affected corporately by dominant economy, social patterns, key symbol marks and core values, etc.. Spatial form of human settlements, being a structured existence, is a materialized, behavioral, and social space; it can be considered as a place where human beings realize their behaviors and a path on which the continuity of their behaviors are kept, also for social practice a territory where currant social structure and social relationships are maintained, strengthened and rebuilt. This article aims to break the boundary of understanding that spatial form of human settlements is pure physical space, furthermore, endeavors to highlight the autonomy status of human beings, focusing on their relationships with certain territories, their interpersonal relationships, man-earth relationships and the state of existence of human beings, elaborating the deeper connotation behind spatial form of human settlements.

Keywords: spatial anthropology, human settlement, spatial pattern, spatial structure

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2236 Effect of Endurance Training on Serum Chemerin Levels and Lipid Profile of Plasma in Obese Women

Authors: A. Moghadasein, M. Ghasemi, S. Fazelifar

Abstract:

Aim: Chemerin is a novel adipokine that play an important role in regulating lipid metabolism and abiogenesis. Chemerin is dependent on autocrine and paracrine signals for the differentiation and maturation of fat cells; it also regulates glucose uptake in fat cells and stimulates lipolysis. It has been reported that in adipocytes, chemerin enhances the insulin-stimulated glucose and causes the phosphorylation of tyrosine in Insulin receptor substrate. According to the studies, Chemerin may increase insulin sensitivity in adipose tissue and is largely associated with Body mass index, triglycerides, and blood pressure in those with normal glucose tolerance. There is limited information available regarding the effect of exercise training on serum chemerin concentrations. The purpose of this study was to investigate the effect of endurance training on serum chemerin levels and lipids of plasma in overweight women. Methodology: This study was a quasi-experimental research with a pre-post test design. After required examination and verification of high pressure by the physician, 22 obese subjects (age: 35.64±5.55 yr, weight: 75.62±9.30 kg, body mass index: 32.4±1.6 kg/m2) were randomly assigned to aerobic training (n= 12) and control (n= 12) groups. Participants completed a questionnaire indicating the lack of sports history during the past six months, the lack of anti-hypertension drugs use, hormone therapy, cardiovascular problems, and complete stoppage of menstrual cycle. Aerobic training was performed 3 times weekly for 8 weeks. Resting levels of chemerin plasma, metabolic parameters were measured prior to and after the intervention. The control group did not participate in any training program. In this study, ethical considerations included the complete description of the objectives to the study participants, ensuring the confidentiality of their information. Kolmogorov-Smirnov and Levin test were used for determining the normal distribution of data and homogeneity of variances, respectively. Analyze of variance with repeated measure were used to investigate the changes in the intra-group and the differences in inter-group of variables. Statistical operations were performed using SPSS 16 and the significance level of the tests was considered at P < 0.05. Results: After an 8 week aerobic training, levels of chemerin plasma were significantly decreased in aerobic trained group when compared with their control groups (p < 0.05).Concurrently, levels of HDL-c were significantly decreased (p < 0.05) whereas, levels of cholesterol, TG and LDL-c, showed no significant changes (p > 0.05). No significant correlations between chemerin levels and weight loss were observed in subjects with overweight women. Conclusion: The present study demonstrated, 8 weeks aerobic training, reduced serum chemerin concentrations in overweight women. Whereas, aerobic training exercise programmers affected the lipid profile response of obese subjects differently. However further research is warranted in order to unravel the molecular mechanism for the range of responses and the role of serum chemerin.

Keywords: chemerin, aerobic training, lipid profile, obese women

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2235 The Socio Demographic Correlates of Post-Traumatic Stress Disorder among Youth Undergoing Domestic Violence in Kenya

Authors: Muchiri Josephine, Qdero Agnes

Abstract:

The current study was conducted during the coronavirus pandemic (COVID-19) period, soon after the lifting of the lockdown measures and schools had just re-opened. It investigated the sociodemographic correlates of Post-Traumatic Stress Disorder (PTSD) among adolescents (13-18 years) who had undergone domestic violence (DV) in Kajiado County, Kenya. The adolescents were administered a sociodemographic questionnaire to ascertain the forms of domestic violence experienced, and those who met the criteria were assessed for the presence of PTSD using the Harvard Trauma Questionnaire (HTQ). Overall, 93(90.3%) had experienced domestic violence, and 57(61.3%) had PTSD; where the severity and prevalence of PTSD increased with increased age, and it also increased significantly among those in higher academic levels, indicating that PTSD prevalence was chronic and additionally influenced by increased academic pressure. Social connections seemed to mitigate PTSD prevalence, whereas, regarding the family background, those living with guardians seemed to have more severe PTSD.

Keywords: age, education level, gender, post-traumatic stress disorder

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2234 Adsorption Kinetics and Equilibria at an Air-Liquid Interface of Biosurfactant and Synthetic Surfactant

Authors: Sagheer A. Onaizi

Abstract:

The adsorption of anionic biosurfactant (surfactin) and anionic synthetic surfactant (sodium dodecylbenzenesulphonate, abbreviated as SDOBS) from phosphate buffer containing high concentrations of co- and counter-ions to the air-buffer interface has been investigated. The self-assembly of the two surfactants at the interface has been monitored through dynamic surface tension measurements. The equilibrium surface pressure-surfactant concentration data in the premicellar region were regressed using Gibbs adsorption equation. The predicted surface saturations for SDOBS and surfactin are and, respectively. The occupied area per an SDOBS molecule at the interface saturation condition is while that occupied by a surfactin molecule is. The surface saturations reported in this work for both surfactants are in a very good agreement with those obtained using expensive techniques such as neutron reflectometry, suggesting that the surface tension measurements coupled with appropriate theoretical analysis could provide useful information comparable to those obtained using highly sophisticated techniques.

Keywords: adsorption, air-liquid interface, biosurfactant, surface tension

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2233 Study of First Hydrogenation Kinetics at Different Temperatures of BCC Alloy 52Ti-12V-36Cr + x wt% Zr (x = 4, 8 & 12)

Authors: Ravi Prakash

Abstract:

The effects of Zr addition on kinetics and hydrogen absorption characteristics of BCC alloy 52Ti-12V-36Cr doped with x wt% of Zr (x = 0, 4, 8 & 12) was investigated. The samples have been characterized by X-ray diffraction, and activation study were made at four different temperatures- 100 oC, 200 oC, 300 oC and 400 oC. First hydrogenation kinetics of alloys were studied at 20 bar of hydrogen pressure and room temperature after giving heat treatment at different temperatures for 6 hours. Among the various Zr doped alloys studied, the composition 52Ti-12V-36Cr + 4wt% Zr shows maximum hydrogen storage capacity of 3.6wt%. Small amount of Zr shows advantageous effects on kinetics of alloy. It was also found out that alloys with the higher Zr concentration can be activated by giving heat treatment at lower temperatures. There is reduction in hydrogen storage capacity with increasing Zr content in the alloy primarily due to increasing abundance of secondary phase as established by X-Ray Diffraction and Scanning Electron Microscope results.

Keywords: hydrogen storage, metal hydrides, bcc alloy, heat treatment

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2232 Antireflection Performance of Graphene Directly Deposited on Silicon Substrate by the Atmospheric Pressure Chemical Vapor Deposition Method

Authors: Samira Naghdi, Kyong Yop Rhee

Abstract:

Transfer-free synthesis of graphene on dielectric substrates is highly desirable but remains challenging. Here, by using a thin sacrificial platinum layer as a catalyst, graphene was deposited on a silicon substrate through a simple and transfer-free synthesis method. During graphene growth, the platinum layer evaporated, resulting in direct deposition of graphene on the silicon substrate. In this work, different growth conditions of graphene were optimized. Raman spectra of the produced graphene indicated that the obtained graphene was bilayer. The sheet resistance obtained from four-point probe measurements demonstrated that the deposited graphene had high conductivity. Reflectance spectroscopy of graphene-coated silicon showed a decrease in reflectance across the wavelength range of 200-800 nm, indicating that the graphene coating on the silicon surface had antireflection capabilities.

Keywords: antireflection coating, chemical vapor deposition, graphene, the sheet resistance

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2231 Study of Dual Fuel Engine as Environmentally Friendly Engine

Authors: Nilam S. Octaviani, Semin

Abstract:

The diesel engine is an internal combustion engine that uses compressed air to combust. The diesel engines are widely used in the world because it has the most excellent combustion efficiency than other types of internal combustion engine.  However, the exhaust emissions of it produce pollutants that are harmful to human health and the environment. Therefore, natural gas used as an alternative fuel using on compression ignition engine to respond those environment issues. This paper aims to discuss the comparison of the technical characteristics and exhaust gases emission from conventional diesel engine and dual fuel diesel engine. According to the study, the dual fuel engine applications have a lower compression pressure and has longer ignition delay compared with normal diesel mode. The engine power is decreased at dual fuel mode. However, the exhaust gases emission on dual fuel engine significantly reduce the nitrogen oxide (NOx), carbon dioxide (CO2) and particular metter (PM) emissions.

Keywords: diesel engine, dual fuel diesel engine, emission reduction, technical characteristics

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2230 Computational Aerodynamics and Aeroacoustics of a Nose Landing Gear

Authors: Kamal Haider

Abstract:

Numerical simulations over landing gear of simplified and partially-dressed configurations with closed cavity have been performed to compute aerodynamically and aeroacoustics parameters using commercial engineering software. The objective of numerical computations is two folds. Firstly, to validate experimental data of newly built nose landing gear and secondly perform high-fidelity calculations using CFD/FW-H hybrid approach, as future engineering challenges need more advanced aircraft configurations such as performance noise and efficiency. Both geometries are used for multi-block structured, and unstructured/hybrid meshed to develop some understanding of physics in terms of aerodynamics and aeroacoustics. Detached Eddy Simulation (DES) approach is employed to compute surface pressure. Also far-field noise calculations have been generated by Ffowcs-William and Hawking solver. Both results of aerodynamics and aeroacoustics are compared with experimental data.

Keywords: landing gear, computational aeroacoustics, computational aerodynamics, detached eddy simulation

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2229 Mathematical Modelling and Parametric Study of Water Based Loop Heat Pipe for Ground Application

Authors: Shail N. Shah, K. K. Baraya, A. Madhusudan Achari

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Loop Heat Pipe is a passive two-phase heat transfer device which can be used without any external power source to transfer heat from source to sink. The main aim of this paper is to have modelling of water-based LHP at varying heat loads. Through figures, how the fluid flow occurs within the loop has been explained. Energy Balance has been done in each section. IC (Iterative Convergence) scheme to find out the SSOT (Steady State Operating Temperature) has been developed. It is developed using Dev C++. To best of the author’s knowledge, hardly any detail is available in the open literature about how temperature distribution along the loop is to be evaluated. Results for water-based loop heat pipe is obtained and compared with open literature and error is found within 4%. Parametric study has been done to see the effect of different parameters on pressure drop and SSOT at varying heat loads.

Keywords: loop heat pipe, modelling of loop heat pipe, parametric study of loop heat pipe, functioning of loop heat pipe

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2228 Evaluation of Fatigue Crack Growth Rate in Weldments

Authors: Pavel Zlabek, Vaclav Mentl

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The fatigue crack growth rate evaluation is a basic experimental characteristic when assessment o f the remaining lifetime is needed. Within the repair welding technology project, the crack growth rate at cyclic loading was measured in base and weld metals and in the situation when cracks were initiated in base metal and grew into the weld metal through heat-affected zone and back to the base metal. Two welding technologies were applied and specimens in as-welded state and after heat treatment were tested. Fatigue crack growth rate measurement was performed on CrMoV pressure vessel steel and the tests were performed at room temperature. The crack growth rate was measured on CCT test specimens (see figure) for both the base and weld metals and also in the case of crack subsequent transition through all the weld zones. A 500 kN MTS controlled electro-hydraulic testing machine and Model 632.13C-20 MTS extensometer were used to perform the tests.

Keywords: cracks, fatigue, steels, weldments

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2227 An Experimental Study on the Measurement of Fuel to Air Ratio Using Flame Chemiluminescence

Authors: Sewon Kim, Chang Yeop Lee, Minjun Kwon

Abstract:

This study is aiming at establishing the relationship between the optical signal of flame and an equivalent ratio of flame. In this experiment, flame optical signal in a furnace is measured using photodiode. The combustion system which is composed of metal fiber burner and vertical furnace and flame chemiluminescence is measured at various experimental conditions. In this study, the flame chemiluminescence of laminar premixed flame is measured by using commercially available photodiode. It is experimentally investigated the relationship between equivalent ratio and photodiode signal. In addition, The strategy of combustion control method is proposed by using the optical signal and fuel pressure. The results showed that certain relationship between optical data of photodiode and equivalence ratio exists and this leads to the successful application of this system for instantaneous measurement of equivalence ration of the combustion system.

Keywords: flame chemiluminescence, photo diode, equivalence ratio, combustion control

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2226 Experimental Study of Nucleate Pool Boiling Heat Transfer Characteristics on Laser-Processed Copper Surfaces of Different Patterns

Authors: Luvindran Sugumaran, Mohd Nashrul Mohd Zubir, Kazi Md Salim Newaz, Tuan Zaharinie Tuan Zahari, Suazlan Mt Aznam, Aiman Mohd Halil

Abstract:

With the fast growth of integrated circuits and the trend towards making electronic devices smaller, the heat dissipation load of electronic devices has continued to go over the limit. The high heat flux element would not only harm the operation and lifetime of the equipment but would also impede the performance upgrade brought about by the iteration of technological updates, which would have a direct negative impact on the economic and production cost benefits of rising industries. Hence, in high-tech industries like radar, information and communication, electromagnetic power, and aerospace, the development and implementation of effective heat dissipation technologies were urgently required. Pool boiling is favored over other cooling methods because of its capacity to dissipate a high heat flux at a low wall superheat without the usage of mechanical components. Enhancing the pool boiling performance by increasing the heat transfer coefficient via surface modification techniques has received a lot of attention. There are several surface modification methods feasible today, but the stability and durability of surface modification are the greatest priority. Thus, laser machining is an interesting choice for surface modification due to its low production cost, high scalability, and repeatability. In this study, different patterns of laser-processed copper surfaces are fabricated to investigate the nucleate pool boiling heat transfer performance of distilled water. The investigation showed that there is a significant enhancement in the pool boiling heat transfer performance of the laser-processed surface compared to the reference surface due to the notable increase in nucleation frequency and nucleation site density. It was discovered that the heat transfer coefficients increased when both the surface area ratio and the ratio of peak-to-valley height of the microstructure were raised. It is believed that the development of microstructures on the surface as a result of laser processing is the primary factor in the enhancement of heat transfer performance.

Keywords: heat transfer coefficient, laser processing, micro structured surface, pool boiling

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2225 Essentiality of Core Strategic Vision in Continuous Cost Reduction Management

Authors: Lai Ving Kam

Abstract:

Many markets are maturing, consumer buying powers are weakening and customer preferences change rapidly. To survive, many adopt fast paced continuous cost reduction and competitive pricing to remain relevance. Marketers desire to push for more sales to increase revenues have intensified competitions at time cannibalize the product and market. The amazing technologies changes have created both hope and despair to the industries. The pressure to constantly reduce cost, on the one hand, create and market new products in cheaper prices and shorter life cycles, on the other has become a continuous endeavour. The twin trends appear irreconcilable. Can core strategic vision provides and adapts new directions in continuous cost reduction? This study investigates core strategic vision able to meet this need, for firms to survive and stay profitable. Under current uncertainty market, are firms falling back on their core strategic visions to take them out of the unfavourable positions?

Keywords: core strategy vision, continuous cost reduction, fashionable products industry, competitive pricing

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2224 Effect Of Selected Food And Nutrition Environments On Prevalence Of Cardio-Metabolic Risk Factors With Emphasis On Worksite Environment In Urban Delhi

Authors: Deepa Shokeen, Bani Tamber Aeri

Abstract:

Food choice is a complex process influenced by the interplay of multiple factors, including physical, socio-cultural and economic factors comprising macro or micro level food environments. While a clear understanding of the relationship between what we eat and the environmental context in which these food choices are made is still needed; it has however now been shown that food environments do play a significant role in the obesity epidemic and increasing cardio-metabolic risk factors. Evidence in other countries indicates that the food environment may strongly influence the prevalence of obesity and cardio-metabolic risk factors among young adults. Although in the Indian context, data does indicate the associations between sedentary lifestyle, stress, faulty diets but very little evidence supports the role of food environment in influencing cardio-metabolic health among employed adults. Thus, this research is required to establish how different environments affect different individuals as individuals interact with the environment on a number of levels. Methodology: The objective of the present study is to assess the effect of selected food and nutrition environments with emphasis on worksite environment and to analyse its impact on the food choices and dietary behaviour of the employees (25-45 years of age) of the organizations under study. In the proposed study an attempt will be made to randomly select various worksite environments from Delhi and NCR. The study will be conducted in two phases. In phase I, Information will be obtained on their socio-demographic profile and various factors influencing their food choices including most commonly consumed foods and most frequently visited eating outlets in and around the work place. Data will also be gathered on anthropometry (height, weight, waist circumference), biochemical parameters (lipid profile and fasting glucose), blood pressure and dietary intake. Based on the findings of phase I, a list of the most frequently visited eating outlets in and around the workplace will be prepared in Phase II. These outlets will then be subjected to nutrition environment assessment survey (NEMS). On the basis of the information gathered from phase I and phase II, influence of selected food and nutrition environments on food choice, dietary behaviour and prevalence of cardio-metabolic risk factors among employed adults will be assessed. Expected outcomes: The proposed study will try to ascertain the impact of selected food and nutrition environments on food choice and dietary intake of the working adults as it is important to learn how these food environments influence the eating perceptions and health behavior of the adults. In addition to this, anthropometry blood pressure and biochemical assessment of the subjects will be done to assess the prevalence of cardio-metabolic risk factors. If the findings indicate that the work environment, where most of these young adults spend their productive hours of the day, influence their health, than perhaps steps maybe needed to make these environments more conducive to health.

Keywords: food and nutrition environment, cardio-metabolic risk factors, India, worksite environment

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2223 An Empirical Review of the Waqf Horizon through Fintech: The Industry 4.0 Wave

Authors: Sikiru O. Aminu, Magda Ismail Abdul Mohsin, Fauziah M. Taib

Abstract:

Fund collections for Waqf projects in some Muslim countries received some boost because of the resuscitation of the cash waqf concept This study envisages that such development can improve the economic empowerment of the poor in contemporary Muslim communities given appropriate collections and effective management of the Waqf institution. Recent developments in the Financial Technology (FINTECH) space portend valuable relevance in the conduct and delivery of social charitable causes such as Waqf around the world. Particularly, emerging areas in FINTECH such as Islamic Crowdfunding (ICF) and blockchain have brought about greater efficiency and effectiveness through cost reduction, faster transactions, wider access, transparency and prompt disclosure of adequate information to relevant stakeholders. These FINTECH options of ICF and blockchain provide veritable opportunities to resuscitate, re-align, synergize and magnify the Islamic Social Finance (ISF) ecosystem of Waqf, Zakat and Sodaqah to generate positive and sustainable impact to the community, environment and the economy at large, with a view to projecting the Maqasid Shari’ah (Objective of the Law Giver). To document the effect of FINTECH on Waqf, this study examined the activities of six banks in Malaysia that signed a pact to utilize FINTECH for waqf collection towards improving the economy. Semi-structured Face to Face interviews were conducted with officers in charge of Waqf in the six banks, founder of the Islamic Crowdfunding platform and senior officers in Waqaf Selangor. Content analysis was used to analyze their responses, and the emergent themes were reported verbatim. Based on the derived themes, survey questionnaires were also administered to 300 customers with respect to the Waqf’s FINTECH functionalities of the identified banks.to further confirm and strengthen the results of the interviews. Simple descriptive analysis was performed on the result of the survey questionnaire to provide clear information on the questions raised. The findings showed a disproportionate level of readiness among the banks, where few of the banks have put structure in place to increase their Waqf collections, others are at their elementary stage. However, the commitment is high across the six banks to achieve their set goals.

Keywords: blockchain, Fintech, Islamic crowdfunding, waqf

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2222 Effect of Nitrogen Gaseous Plasma on Cotton Fabric Dyed with Reactive Yellow105

Authors: Mohammad Mirjalili, Hamid Akbarpour

Abstract:

In this work, a bleached well cotton sample was dyed with reactive yellow105 dye and subsequently, the dyed sample was exposed to the plasma condition containing Nitrogen gas at 1 and 5 minutes of plasma exposure time, respectively. The effect of plasma on surface morphology fabric was studied by Scanning Electronic Microscope (SEM). CIELab, K/S, and %R of samples (treated and untreated samples) were measured by a reflective spectrophotometer, and consequently, the experiments show that the sample dyed with Reactive yellow 105 after being washed, with the increase in the operation time of plasma, its dye fastness decreases. In addition, the increase in plasma operation time at constant pressure would increase the destructing effect on the surface morphology of samples dyed with reactive yellow105.

Keywords: cotton fabric, nitrogen cold plasma, reflective spectrophotometer, scanning electronic microscope (SEM), reactive yellow105 dye

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2221 Physicochemical and Optical Characterization of Rutile TiO2 Thin Films Grown by APCVD Technique

Authors: Dalila Hocine, Mohammed Said Belkaid, Abderahmane Moussi

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In this study, pure rutile TiO2 thin films were directly synthesized on silicon substrates by Atmospheric Pressure Chemical Vapor Deposition technique (APCVD) using TiCl4 as precursor. We studied the physicochemical properties and the optical properties of the produced coatings by means of standard characterization techniques of Fourier Transform Infrared Spectroscopy (FTIR) combined with UV-Vis Reflectance Spectrophotometry. The absorption peaks at 423 cm-1 and 610 cm-1 were observed for the rutile TiO2 thin films, by FTIR measurements. The absorption peak at 739 cm-1 due to the vibration of the Ti-O bonds, was also detected. UV-Vis Reflectance Spectrophotometry is employed for measuring the optical band gap from the measurements of the TiO2 films reflectance. The optical band gap was then extracted from the reflectance data for the TiO2 sample. It was estimated to be 3.05 eV which agrees with the band gap of commercial rutile TiO2 sample.

Keywords: titanium dioxide, physicochemical properties, APCVD, FTIR, band gap

Procedia PDF Downloads 389
2220 Linguistic Politeness in Higher Education Teaching Chinese as an Additional Language

Authors: Leei Wong

Abstract:

Changes in globalized contexts precipitate changing perceptions concerning linguistic politeness practices. Within these changing contexts, misunderstanding or stereotypification of politeness norms may lead to negative consequences such as hostility or even communication breakdown. With China’s rising influence, the country is offering a vast potential market for global economic development and diplomatic relations and opportunities for intercultural interaction, and many outside China are subsequently learning Chinese. These trends bring both opportunities and pitfalls for intercultural communication, including within the important field of politeness awareness. One internationally recognized benchmark for the study and classification of languages – the updated 2018 CEFR (Common European Framework of Reference for Language) Companion Volume New Descriptors (CEFR/CV) – classifies politeness as a B1 (or intermediate) level descriptor on the scale of Politeness Conventions. This provides some indication of the relevance of politeness awareness within new globalized contexts for fostering better intercultural communication. This study specifically examines Bald on record politeness strategies presented in current beginner TCAL textbooks used in Australian tertiary education through content-analysis. The investigation in this study involves the purposive sampling of commercial textbooks published in America and China followed by interpretive content analysis. The philosophical position of this study is therefore located within an interpretivist ontology, with a subjectivist epistemological perspective. It sets out with the aim to illuminate the characteristics of Chinese Bald on record strategies that are deemed significant in the present-world context through Chinese textbook writers and curriculum designers. The data reveals significant findings concerning politeness strategies in beginner stage curriculum, and also opens the way for further research on politeness strategies in intermediate and advanced level textbooks for additional language learners. This study will be useful for language teachers, and language teachers-in-training, by generating awareness and providing insights and advice into the teaching and learning of Bald on record politeness strategies. Authors of textbooks may also benefit from the findings of this study, as awareness is raised of the need to include reference to understanding politeness in language, and how this might be approached.

Keywords: linguistic politeness, higher education, Chinese language, additional language

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2219 Far-Field Acoustic Prediction of a Supersonic Expanding Jet Using Large Eddy Simulation

Authors: Jesus Ruano, Asensi Oliva

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The hydrodynamic field generated by a jet expansion is computed via three dimensional compressible Large Eddy Simulation (LES). Finite Volume Method (FVM) will be the discretization used during this simulation as well as hybrid schemes based on Kinetic Energy Preserving (KEP) schemes and up-winding Godunov based schemes with instabilities detectors. Velocity and pressure fields will be stored at different surfaces near the jet, but far enough to enclose all the fluctuations, in order to use them as input for the acoustic solver. The acoustic field is obtained in the far-field region at several locations by means of a hybrid method based on Ffowcs-Williams and Hawkings (FWH) equation. This equation will be formulated in the spectral domain, via Fourier Transform of the acoustic sources, which are modeled from the results of the initial simulation. The obtained results will allow the study of the broadband noise generated as well as sound directivities.

Keywords: far-field noise, Ffowcs-Williams and Hawkings, finite volume method, large eddy simulation, jet noise

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2218 An ab initioStudy of the Structural, Elastic, Electronic, and Optical Properties of the Perovskite ScRhO3

Authors: L. Foudia, K. Haddadi, M. Reffas

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First principles study of structural, elastic, electronic and optical properties of the monoclinic perovskite type ScRhO₃ has been reported using the pseudo-potential plane wave method within the local density approximation. The calculated lattice parameters, including the lattice constants and angle β, are in excellent agreement with the available experimental data, which proving the reliability of the chosen theoretical approach. Pressure dependence up to 20 GPa of the single crystal and polycrystalline elastic constants has been investigated in details using the strain-stress approach. The mechanical stability, ductility, average elastic wave velocity, Debye temperature and elastic anisotropy were also assessed. Electronic band structure and density of states (DOS) demonstrated its semiconducting nature showing a direct band gap of 1.38 eV. Furthermore, several optical properties, such as absorption coefficient, reflectivity, refractive index, dielectric function, optical conductivity and electron energy loss function, have been calculated for radiation up to 40 eV.

Keywords: ab-initio, perovskite, DFT, band gap

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2217 The Interventions to Parents Caring Children with Attention Deficit/Hyperactivity Disorder in Hong Kong

Authors: Wing Chi Wong

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Globally, studying parents caring for children with attention deficit/ hyperactivity disorder (ADHD) is valuable in order to design measures in supporting those parents by health care providers and government. Such parents in Hong Kong seem to encounter detrimental stress and enormous difficulties which are exacerbated by the traditional Chinese culture, exclusion from social members and fiercely competitive educational system. However, seldom studies scrutinize this issue in Hong Kong. This article aims to review the literature regarding parents caring offsprings with ADHD in Hong Kong. Criteria were set for searching among published studies listed in various databases, including MEDLINE, CINCAHL, PsycINFO, ProQuest, Embase, Cochrane Library and Springer Link. Articles with words 'Attention Deficit Hyperactivity Disorder', 'parenting', 'parent', 'family', 'father', 'mother', 'care' in titles and abstracts were identified. Articles with all types of research designs and methods, regardless in English or Chinese, were included. They were limited to years between January 2008 and September 2018. Four relevant studies have resulted. Of them, two were exploratory studies, one was a qualitative study, and one was a survey. Samples were recruited from child psychiatric clinic, Child and Adolescent Mental Health Unit, or multiple family group therapy centres. Authors proclaimed that quality of life of those parents was usually low; particularly mothers perceived a higher stress than fathers; parenting barriers existed; conflicts were commonly raised in parent-child relationship resulting in probable maltreatment to children. Previous studies generally suggested the potential negative outcomes of parents caring children with ADHD. The types and effectiveness of interventions to those parents on relieving their tortures under Hong Kong context had not been explored and systematically evaluated. The scanty studies and existing understanding could not give a promising conclusion pertaining to the appropriate family intervention to parents living with children with ADHD. A stringent research design is necessary to establish evidence on the effectiveness of interventions for those families.

Keywords: attention deficit/ hyperactivity disorder, Hong Kong, parents, interventions

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2216 Simulations of High-Intensity, Thermionic Electron Guns for Electron Beam Thermal Processing Including Effects of Space Charge Compensation

Authors: O. Hinrichs, H. Franz, G. Reiter

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Electron guns have a key function in a series of thermal processes, like EB (electron beam) melting, evaporation or welding. These techniques need a high-intensity continuous electron beam that defocuses itself due to high space charge forces. A proper beam transport throughout the magnetic focusing system can be ensured by a space charge compensation via residual gas ions. The different pressure stages in the EB gun cause various degrees of compensation. A numerical model was installed to simulate realistic charge distributions within the beam by using CST-Particle Studio code. We will present current status of beam dynamic simulations. This contribution will focus on the creation of space charge ions and their influence on beam and gun components. Furthermore, the beam transport in the gun will be shown for different beam parameters. The electron source allows to produce beams with currents of 3 A to 15 A and energies of 40 keV to 45 keV.

Keywords: beam dynamic simulation, space charge compensation, thermionic electron source, EB melting, EB thermal processing

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2215 Numerical and Experimental Investigation of the Aerodynamic Performances of Counter-Rotating Rotors

Authors: Ibrahim Beldjilali, Adel Ghenaiet

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The contra-rotating axial machine is a promising solution for several applications, where high pressure and efficiencies are needed. Also, they allow reducing the speed of rotation, the radial spacing and a better flexibility of use. However, this requires a better understanding of their operation, including the influence of second rotor on the overall aerodynamic performances. This work consisted of both experimental and numerical studies to characterize this counter-rotating fan, especially the analysis of the effects of the blades stagger angle and the inter-distance between the rotors. The experimental study served to validate the computational fluid dynamics model (CFD) used in the simulations. The numerical study permitted to cover a wider range of parameter and deeper investigation on flow structures details, including the effects of blade stagger angle and inter-distance, associated with the interaction between the rotors. As a result, there is a clear improvement in aerodynamic performance compared with a conventional machine.

Keywords: aerodynamic performance, axial fan, counter rotating rotors, CFD, experimental study

Procedia PDF Downloads 154