Search results for: the economic behavior of households.
2764 Study on Damage Tolerance Behavior of Integrally Stiffened Panel and Conventional Stiffened Panel
Authors: M. Adeel
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The damage tolerance behavior of integrally and conventional stiffened panel is investigated based on the fracture mechanics and finite element analysis. The load bearing capability and crack growth characteristic of both types of the stiffened panels having same configuration subjected to distributed tensile load is examined in this paper. A fourteen-stringer stiffened panel is analyzed for a central skin crack propagating towards the adjacent stringers. Stress intensity factors and fatigue crack propagation rates of both types of the stiffened panels are then compared. The analysis results show that integral stiffening causes higher stress intensity factor than conventional stiffened panel as the crack tip passes through the stringer and the integrally stiffened panel has less load bearing capability than the riveted stiffened panel.Keywords: Conventional Stiffened Structure, Damage Tolerance, Finite Element Analysis, Integrally Stiffened Structure, Stress Intensity Factor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28962763 A Study of Various Numerical Turbulence Modeling Methods in Boundary Layer Excitation of a Square Ribbed Channel
Authors: Hojjat Saberinejad, Adel Hashiehbaf, Ehsan Afrasiabian
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Among the various cooling processes in industrial applications such as: electronic devices, heat exchangers, gas turbines, etc. Gas turbine blades cooling is the most challenging one. One of the most common practices is using ribbed wall because of the boundary layer excitation and therefore making the ultimate cooling. Vortex formation between rib and channel wall will result in a complicated behavior of flow regime. At the other hand, selecting the most efficient method for capturing the best results comparing to experimental works would be a fascinating issue. In this paper 4 common methods in turbulence modeling: standard k-e, rationalized k-e with enhanced wall boundary layer treatment, k-w and RSM (Reynolds stress model) are employed to a square ribbed channel to investigate the separation and thermal behavior of the flow in the channel. Finally all results from different methods which are used in this paper will be compared with experimental data available in literature to ensure the numerical method accuracy.Keywords: boundary layer, turbulence, numerical method, rib cooling
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16832762 Anisotropic Shear Strength of Sand Containing Plastic Fine Materials
Authors: Alaa H. J. Al-Rkaby, A. Chegenizadeh, H. R. Nikraz
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Anisotropy is one of the major aspects that affect soil behavior, and extensive efforts have investigated its effect on the mechanical properties of soil. However, very little attention has been given to the combined effect of anisotropy and fine contents. Therefore, in this paper, the anisotropic strength of sand containing different fine content (F) of 5%, 10%, 15%, and 20%, was investigated using hollow cylinder tests under different principal stress directions of α = 0° and α = 90°. For a given principal stress direction (α), it was found that increasing fine content resulted in decreasing deviator stress (q). Moreover, results revealed that all fine contents showed anisotropic strength where there is a clear difference between the strength under 0° and the strength under 90°. This anisotropy was greatest under F = 5% while it decreased with increasing fine contents, particularly at F = 10%. Mixtures with low fine content show low contractive behavior and tended to show more dilation. Moreover, all sand-clay mixtures exhibited less dilation and more compression at α = 90° compared with that at α = 0°.Keywords: Anisotropy, principal stress direction, fine content, hollow cylinder sample.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10702761 Study of the Late Phase of Core Degradation during Reflooding by Safety Injection System for VVER1000 with ASTECv2 Computer Code
Authors: Antoaneta Stefanova, Rositsa Gencheva, Pavlin Groudev
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This paper presents the modeling approach in SBO sequence for VVER 1000 reactors and describes the reactor core behavior at late in-vessel phase in case of late reflooding by HPIS and gives preliminary results for the ASTECv2 validation. The work is focused on investigation of plant behavior during total loss of power and the operator actions. The main goal of these analyses is to assess the phenomena arising during the Station blackout (SBO) followed by primary side high pressure injection system (HPIS) reflooding of already damaged reactor core at very late “in-vessel” phase. The purpose of the analyses is to define how the later HPIS switching on can delay the time of vessel failure or possibly avoid vessel failure. The times for HPP injection were chosen based on previously performed investigations.Keywords: VVER, operator action validation, reflooding of overheated reactor core, ASTEC computer code.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14322760 Effect of Steel Fibers on Flexural Behavior of Normal and High Strength Concrete
Authors: K. M. Aldossari, W. A. Elsaigh, M. J. Shannag
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An experimental study was conducted to investigate the effect of hooked-end steel fibers on the flexural behavior of normal and high strength concrete matrices. The fibers content appropriate for the concrete matrices investigated was also determined based on flexural tests on standard prisms. Parameters investigated include: matrix compressive strength ranging from 45 MPa to 70 MPa, corresponding to normal and high strength concrete matrices respectively; fibers volume fraction including 0, 0.5%, 0.76% and 1%, equivalent to 0, 40, 60, and 80 kg/m3 of hooked-end steel fibers respectively. Test results indicated that flexural strength and toughness of normal and high strength concrete matrices were significantly improved with the increase in the fibers content added; whereas a slight improvement in compressive strength was observed for the same matrices. Furthermore, the test results indicated that the effect of increasing the fibers content was more pronounced on increasing the flexural strength of high strength concrete than that of normal concrete.
Keywords: Concrete, flexural strength, toughness, steel fibers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19102759 Study of Barriers to Women's Entrepreneurship Development among Iranian Women (Case Entrepreneur Women)
Authors: F. Niazkar, N. Arab-Moghaddam
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In this research, effort was made to identify and evaluate barriers to the development of entrepreneurship among Iranian entrepreneur women who were graduated from universities. In this study, perspectives of thirty-seven available entrepreneur women were examined. In order to prepare questionnaires and receive knowledge about barriers among these women, seven cases of entrepreneur women took part in in-depth interviews. Then, to evaluate the importance of barriers, the researchers made a questionnaire with closed questions in which the barriers were classified into the following categories: personal-familial barriers; socio-cultural barriers; economic-financial-commercial barriers; and structural barriers. Entrepreneur women were requested to rate the importance of each item. The results indicated that there were different obstacles among entrepreneur women. The order of the important barriers was as fallow: economic-financial-commercial, structural, socio-cultural, and personal-familial.Keywords: Barriers to Entrepreneurship, Entrepreneur Women
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31962758 Nuclear Fuel Safety Threshold Determined by Logistic Regression Plus Uncertainty
Authors: D. S. Gomes, A. T. Silva
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Analysis of the uncertainty quantification related to nuclear safety margins applied to the nuclear reactor is an important concept to prevent future radioactive accidents. The nuclear fuel performance code may involve the tolerance level determined by traditional deterministic models producing acceptable results at burn cycles under 62 GWd/MTU. The behavior of nuclear fuel can simulate applying a series of material properties under irradiation and physics models to calculate the safety limits. In this study, theoretical predictions of nuclear fuel failure under transient conditions investigate extended radiation cycles at 75 GWd/MTU, considering the behavior of fuel rods in light-water reactors under reactivity accident conditions. The fuel pellet can melt due to the quick increase of reactivity during a transient. Large power excursions in the reactor are the subject of interest bringing to a treatment that is known as the Fuchs-Hansen model. The point kinetic neutron equations show similar characteristics of non-linear differential equations. In this investigation, the multivariate logistic regression is employed to a probabilistic forecast of fuel failure. A comparison of computational simulation and experimental results was acceptable. The experiments carried out use the pre-irradiated fuels rods subjected to a rapid energy pulse which exhibits the same behavior during a nuclear accident. The propagation of uncertainty utilizes the Wilk's formulation. The variables chosen as essential to failure prediction were the fuel burnup, the applied peak power, the pulse width, the oxidation layer thickness, and the cladding type.Keywords: Logistic regression, reactivity-initiated accident, safety margins, uncertainty propagation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10092757 Ontology-Based Backpropagation Neural Network Classification and Reasoning Strategy for NoSQL and SQL Databases
Authors: Hao-Hsiang Ku, Ching-Ho Chi
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Big data applications have become an imperative for many fields. Many researchers have been devoted into increasing correct rates and reducing time complexities. Hence, the study designs and proposes an Ontology-based backpropagation neural network classification and reasoning strategy for NoSQL big data applications, which is called ON4NoSQL. ON4NoSQL is responsible for enhancing the performances of classifications in NoSQL and SQL databases to build up mass behavior models. Mass behavior models are made by MapReduce techniques and Hadoop distributed file system based on Hadoop service platform. The reference engine of ON4NoSQL is the ontology-based backpropagation neural network classification and reasoning strategy. Simulation results indicate that ON4NoSQL can efficiently achieve to construct a high performance environment for data storing, searching, and retrieving.
Keywords: Hadoop, NoSQL, ontology, backpropagation neural network, and high distributed file system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9932756 Leadership Branding for Sustainable Customer Engagement
Authors: Fauziah Sh. Ahmad, Rosmini Omar, Siti Zaleha Abdul Rasid, Muslim Amin
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The purpose of this paper is to examine the inter relationships among various leadership branding constructs of entrepreneurs in small and medium sized enterprises (SMEs). We employ a quantitative structural equation modeling through a new leadership branding engagement model comprises constructs of leader-s or entrepreneur-s personality, branding practice and customer engagement. The results confirm that there are significant relationships between the three constructs and the major fit indices indicate that the data fits the proposed model. The findings provide insights and fill in the literature gaps on statistically validated representation of leadership branding for SMEs across new economic regions of Malaysia that may implicate other economic zones with similar situations. This study extends the establishment of a leadership branding engagement model with a new mechanism of using leaders- personality as a predictor to branding practice and customer engagement performance.Keywords: Leadership Branding, Malaysia Brands, Customer Engagement, SME Branding.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24492755 Knowledge and Attitude: Challenges for Continuing Education in Health
Authors: André M. Senna, Mary L. G. S. Senna, Rosa M. Machado-de-Sena
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One of the great challenges presented in educational practice is how to ensure the students not only acquire knowledge of training courses throughout their academic life, but also how to apply it in their current professional activities. Consequently, aiming to incite changes in the education system of healthcare professionals noticed the inadequacy of the training providers to solve the social problems related to health, the education related to these procedures should initiate in the earliest years of process. Following that idea, there is another question that needs an answer: If the change in the education should start sooner, in the period of basic training of healthcare professionals, what guidelines should a permanent education program incorporate to promote changes in an already established system? For this reason, the objective of this paper is to present different views of the teaching-learning process, with the purpose of better understanding the behavior adopted by healthcare professionals, through bibliographic study. The conclusion was that more than imparting knowledge to the individual, a larger approach is necessary on permanent education programs concerning the performance of professional health services in order to foment significant changes in education.
Keywords: Health education, continuing education, training, behavior.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9082754 Middle East towards Incubator Benefits: Case Studies
Authors: Hanadi Mubarak AL-Mubaraki, Michael Busler
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In the context of business incubation (BI) as strategic enablers, this paper critically reviews the literature relating to the strategic benefits of BI in the Middle East. The taxonomy of BI benefits in the strategic elements on 1) type, 2) financial model, 3) services, 4) objectives, 5) number of clients, 6) number of graduates, and 7) jobs creation. Understanding the importance of BI benefits can be significant in the economic development although most incubators lead to diversify the economy. Thus, taxonomies of the benefits of BI are produced from both the academic literature and published case studies. In this way, a classification of strategic benefits elements as they relate to incubators has been developed to provide a greater understanding of the benefits needed to obtain a specific element. The result of this paper is Business incubators is aimed entrepreneurship, jobs creation, research commercialization and profitable enterprises in Middle Eastern countries.Keywords: Economic Development, Incubators, Middle East, Strategic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22132753 Assessment the Effect of Setback in Height of Frame on Reinforcement Structures
Authors: Farshad Mehrabi, Ali kheirodin, Mohsen Gerami
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Ambiguities in effects of earthquake on various structures in all earthquake codes would necessitate more study and research concerning influential factors on dynamic behavior. Previous studies which were done on different features in different buildings play a major role in the type of response a structure makes to lateral vibrations. Diagnosing each of these irregularities can help structure designers in choosing appropriate setbacks for decreasing possible damages. Therefore vertical setback is one of the irregularity factors in the height of the building where can be seen in skyscrapers and hotels. Previous researches reveal notable changes in the place of these setbacks showing dynamic response of the structure. Consequently analyzing 48 models of concrete frames for 3, 6 and 9 stories heights with three different bays in general shape of a surface decline by height have been constructed in ETABS2000 software, and then the shape effect of each and every one of these frames in period scale has been discussed. The result of this study reveals that not only mass, stiffness and height but also shape of the frame is influential.Keywords: period, concrete frame, irregularity in height, decrease in plan surface, dynamic behavior
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13912752 Perspectives and Outcomes of a Long and Shorter Community Mental Health Program
Authors: Danielle Klassen, Reiko Yeap, Margo Schmitt-Boshnick, Scott Oddie
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The development of the 7-week Alberta Happiness Basics program was initiated in 2010 in response to the need for community mental health programming. This provincial wide program aims to increase overall happiness and reduce negative thoughts and feelings through a positive psychology intervention. While the 7-week program has proven effective, a shortened 4-week program has additionally been developed to address client needs. In this study, participants were interviewed to determine if the 4- and 7-week programs had similar success of producing lasting behavior change at 3, 6, and 9 months post-program. A health quality of life (HQOL) measure was also used to compare the two programs and examine patient outcomes. Quantitative and qualitative analysis showed significant improvements in HQOL and sustainable behavior change for both programs. Findings indicate that the shorter, patient-centered program was effective in increasing happiness and reducing negative thoughts and feelings.Keywords: Primary care, mental health, depression, short duration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9182751 Nonlinear Finite Element Analysis of Composite Cantilever Beam with External Prestressing
Authors: R. I. Liban, N. Tayşi
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This paper deals with a nonlinear finite element analysis to examine the behavior up to failure of cantilever composite steel-concrete beams which are prestressed externally. 'Pre-' means stressing the high strength external tendons in the steel beam section before the concrete slab is added. The composite beam contains a concrete slab which is connected together with steel I-beam by means of perfect shear connectors between the concrete slab and the steel beam which is subjected to static loading. A finite element analysis will be done to study the effects of external prestressed tendons on the composite steel-concrete beams by locating the tendons in different locations (profiles). ANSYS version 12.1 computer program is being used to analyze the represented three-dimensional model of the cantilever composite beam. This model gives all these outputs, mainly load-displacement behavior of the cantilever end and in the middle span of the simple support part.
Keywords: Composite steel-concrete beams, external prestressing, finite element analysis, ANSYS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14012750 Mathematical modeling of Bi-Substrate Enzymatic Reactions with Ping-Pong Mechanism in the Presence of Competitive Inhibitors
Authors: Rafayel A. Azizyan, Aram E. Gevogyan, Valeri B. Arakelyan, Emil S. Gevorgyan
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The mathematical modeling of different biological processes is usually used to predict or assess behavior of systems in which these processes take place. This study deals with mathematical and computer modeling of bi-substrate enzymatic reactions with ping-pong mechanism, which play an important role in different biochemical pathways. Besides that, three models of competitive inhibition were designed using different software packages. The main objective of this study is to represent the results from in silico investigation of bi-substrate enzymatic reactions with ordered pingpong mechanism in the presence of competitive inhibitors, as well as to describe in details the inhibition effects. The simulation of the models with certain kinetic parameters allowed investigating the behavior of reactions as well as determined some interesting aspects concerning influence of different cases of competitive inhibition. Simultaneous presence of two inhibitors, competitive to the S1 and S2 substrates have been studied. Moreover, we have found the pattern of simultaneous influence of both inhibitors.Keywords: Mathematical modeling, bi-substrate enzymatic reactions, ping-pong mechanism, competitive inhibition.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35692749 Effect of Linear Thermal Gradient on Steady-State Creep Behavior of Isotropic Rotating Disc
Authors: Minto Rattan, Tania Bose, Neeraj Chamoli
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The present paper investigates the effect of linear thermal gradient on the steady-state creep behavior of rotating isotropic disc using threshold stress based Sherby’s creep law. The composite discs made of aluminum matrix reinforced with silicon carbide particulate has been taken for analysis. The stress and strain rate distributions have been calculated for discs rotating at linear thermal gradation using von Mises’ yield criterion. The material parameters have been estimated by regression fit of the available experimental data. The results are displayed and compared graphically in designer friendly format for the above said temperature profile with the disc operating under uniform temperature profile. It is observed that radial and tangential stresses show minor variation and the strain rates vary significantly in the presence of thermal gradation as compared to disc having uniform temperature.Keywords: Creep, isotropic, steady-state, thermal gradient.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8372748 Effect of Scalping on the Mechanical Behavior of Coarse Soils
Authors: Nadine Ali Hassan, Ngoc Son Nguyen, Didier Marot, Fateh Bendahmane
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This paper aims at presenting a study of the effect of scalping methods on the mechanical properties of coarse soils by resorting to numerical simulations based on the discrete element method (DEM) and experimental triaxial tests. Two reconstitution methods are used, designated as scalping method and substitution method. Triaxial compression tests are first simulated on a granular materials with a grap graded particle size distribution by using the DEM. We study the effect of these reconstitution methods on the stress-strain behavior of coarse soils with different fine contents and with different ways to control the densities of the scalped and substituted materials. Experimental triaxial tests are performed on original mixtures of sands and gravels with different fine contents and on their corresponding scalped and substituted samples. Numerical results are qualitatively compared to experimental ones. Agreements and discrepancies between these results are also discussed.Keywords: Coarse soils, scalping, substitution, discrete element method, triaxial test.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6402747 The Study of the Correlation of Proactive Coping and Retirement Planning: An Example of Senior Civil Servants in Taiwan
Authors: Ya-Hui Lee, Chien-Hung Hsieh, Ching-Yi Lu
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Demographic aging is the major problem that Taiwanese society is facing, and retirement life adaptation is the most concerning issue. In recent years, studies have suggested that in order to have successful aging and retirement planning, a view for the future is necessary. In Taiwan, civil servants receive better pensions and retirement benefits than do other industries. Therefore, their retirement preparation is considerably more significant than other senior groups in Taiwan. The purpose of this study is to understand the correlation of proactive coping and retirement planning of senior civil servants in Taiwan. The method is conducted by questionnaire surveys, with 342 valid questionnaires collected. The results of this study are: 1. The background variables of the interviewees, including age, perceived economic statuses, and retirement statuses, are all significantly related to their proactive coping and retirement planning. 2. Regarding age, the interviewees with ages 55 and above have better proactive coping and retirement planning than those with ages 45 and below. 3. In the aspect of perceived economic statuses, the participants who feel “very good” economic statuses have better proactive coping ability and retirement readiness than those who feel “bad” and “very bad”. 4. Retirees have better proactive coping and retirement planning than those who are still working. 5. Monthly income is significant in retirement planning only. The participants’ retirement planning would be better if they have higher incomes. Furthermore, the participants’ retirement planning would be better if their revenue were €1453~€1937, than if their revenue were below €968. 6. There are positive correlations between proactive coping and retirement planning. 7. Proactive coping can predict retirement planning. The result of this study will be provided as references to the Taiwan government for educational retirement planning policies.
Keywords: Civil servants, proactive coping, retirement planning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17532746 Nanobiocomposites with Enhanced Cell Proliferation and Improved Mechanical Properties Based on Organomodified-Nanoclay and Silicone Rubber
Authors: M. S. Hosseini, M. Tazzoli-Shadpour, I. Amjadi, A. A. Katbab, E. Jaefargholi-Rangraz
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Bionanotechnology deals with nanoscopic interactions between nanostructured materials and biological systems. Polymer nanocomposites with optimized biological activity have attracted great attention. Nanoclay is considered as reinforcing nanofiller in manufacturing of high performance nanocomposites. In current study, organomodified-nanoclay with negatively charged silicate layers was incorporated into biomedical grade silicone rubber. Nanoparticle loading has been tailored to enhance cell behavior. Addition of nanoparticles led to improved mechanical properties of substrate with enhanced strength and stiffness while no toxic effects was observed. Results indicated improved viability and proliferation of cells by addition of nanofillers. The improved mechanical properties of the matrix result in proper cell response through adjustment and arrangement of cytoskeletal fibers. Results can be applied in tissue engineering when enhanced substrates are required for improvement of cell behavior for in vivo applications.
Keywords: Biocompatibility, Composite, Organomodified- Nanoclay, Proliferation
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19332745 Circular Raft Footings Strengthened by Stone Columns under Dynamic Harmonic Loads
Authors: R. Ziaie Moayed, A. Mahigir
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Stone column technique has been successfully employed to improve the load-settlement characteristics of foundations. A series of finite element numerical analyses of harmonic dynamic loading have been conducted on strengthened raft footing to study the effects of single and group stone columns on settlement of circular footings. The settlement of circular raft footing that improved by single and group of stone columns are studied under harmonic dynamic loading. This loading is caused by heavy machinery foundations. A detailed numerical investigation on behavior of single column and group of stone columns is carried out by varying parameters like weight of machinery, loading frequency and period. The result implies that presence of single and group of stone columns enhanced dynamic behavior of the footing so that the maximum and residual settlement of footing significantly decreased.Keywords: Finite element analysis, harmonic loading, settlement, stone column.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10122744 Analysis of Mechanical Properties for AP/HTPB Solid Propellant under Different Loading Conditions
Authors: Walid M. Adel, Liang Guo-Zhu
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To investigate the characterization of the mechanical properties of composite solid propellant (CSP) based on hydroxyl-terminated polybutadiene (HTPB) at different temperatures and strain rates, uniaxial tensile tests were conducted over a range of temperatures -60 °C to +76 °C and strain rates 0.000164 to 0.328084 s-1 using a conventional universal testing machine. From the experimental data, it can be noted that the mechanical properties of AP/HTPB propellant are mainly dependent on the applied strain rate and the temperature condition. The stress-strain responses exhibited an initial yielding followed by the viscoelastic phase, which was strongly affected by the strain rate and temperature. It was found that the mechanical properties increased with both increasing strain rate and decreasing temperature. Based on the experimental tests, the master curves of the tensile properties are drawn using predetermined shift factor and the results were discussed. This work is a first step in preliminary investigation the nonlinear viscoelasticity behavior of CSP.
Keywords: AP/HTPB composite solid propellant, mechanical behavior, nonlinear viscoelastic, tensile test, master curves.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20232743 Corrosion Evaluation of Zinc Coating Prepared by Two Types of Electric Currents
Authors: M. Sajjadnejad, H. Karimi Abadeh
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In this research, zinc coatings were fabricated by electroplating process in a sulfate solution under direct and pulse current conditions. In direct and pulse current conditions, effect of maximum current was investigated on the coating properties. Also a comparison was made between the obtained coatings under direct and pulse current. Morphology of the coatings was investigated by scanning electron microscopy (SEM). Corrosion behavior of the coatings was investigated by potentiodynamic polarization test. In pulse current conditions, the effect of pulse frequency and duty cycle was also studied. The effect of these conditions and parameters were also investigated on morphology and corrosion behavior. All of DC plated coatings are showing a distinct passivation area in -1 to -0.4 V range. Pulsed current coatings possessed a higher corrosion resistance. The results showed that current density is the most important factor regarding the fabrication process. Furthermore, a rise in duty cycle deteriorated corrosion resistance of coatings. Pulsed plated coatings performed almost 10 times better than DC plated coatings.
Keywords: Corrosion, duty cycle, pulsed current, zinc.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8172742 Analyzing Current Transformer’s Transient and Steady State Behavior for Different Burden’s Using LabVIEW Data Acquisition Tool
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Current transformers (CTs) are used to transform large primary currents to a small secondary current. Since most standard equipment’s are not designed to handle large primary currents the CTs have an important part in any electrical system for the purpose of Metering and Protection both of which are integral in Power system. Now a days due to advancement in solid state technology, the operation times of the protective relays have come to a few cycles from few seconds. Thus, in such a scenario it becomes important to study the transient response of the current transformers as it will play a vital role in the operating of the protective devices.
This paper shows the steady state and transient behavior of current transformers and how it changes with change in connected burden. The transient and steady state response will be captured using the data acquisition software LabVIEW. Analysis is done on the real time data gathered using LabVIEW. Variation of current transformer characteristics with changes in burden will be discussed.
Keywords: Accuracy, Accuracy limiting factor, Burden, Current Transformer, Instrument Security factor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33072741 Socio-Economic Determinants of Physical Activity of Non-Manual Workers, Including the Early Senior Group, from the City of Wroclaw in Poland
Authors: Daniel Puciato, Piotr Oleśniewicz, Julita Markiewicz-Patkowska, Krzysztof Widawski, Michał Rozpara, Władysław Mynarski, Agnieszka Gawlik, Małgorzata Dębska, Soňa Jandová
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Physical activity as a part of people’s everyday life reduces the risk of many diseases, including those induced by lifestyle, e.g. obesity, type 2 diabetes, osteoporosis, coronary heart disease, degenerative arthritis, and certain types of cancer. That refers particularly to professionally active people, including the early senior group working on non-manual positions. The aim of the study is to evaluate the relationship between physical activity and the socio-economic status of non-manual workers from Wroclaw—one of the biggest cities in Poland, a model setting for such investigations in this part of Europe. The crucial problem in the research is to find out the percentage of respondents who meet the health-related recommendations of the World Health Organization (WHO) concerning the volume, frequency, and intensity of physical activity, as well as to establish if the most important socio-economic factors, such as gender, age, education, marital status, per capita income, savings and debt, determine the compliance with the WHO physical activity recommendations. During the research, conducted in 2013, 1,170 people (611 women and 559 men) aged 21–60 years were examined. A diagnostic poll method was applied to collect the data. Physical activity was measured with the use of the short form of the International Physical Activity Questionnaire with extended socio-demographic questions, i.e. concerning gender, age, education, marital status, income, savings or debts. To evaluate the relationship between physical activity and selected socio-economic factors, logistic regression was used (odds ratio statistics). Statistical inference was conducted on the adopted ex ante probability level of p<0.05. The majority of respondents met the volume of physical effort recommended for health benefits. It was particularly noticeable in the case of the examined men. The probability of compliance with the WHO physical activity recommendations was highest for workers aged 21–30 years with secondary or higher education who were single, received highest incomes and had savings. The results indicate the relations between physical activity and socio-economic status in the examined women and men. People with lower socio-economic status (e.g. manual workers) are physically active primarily at work, whereas those better educated and wealthier implement physical effort primarily in their leisure time. Among the investigated subjects, the youngest group of non-manual workers have the best chances to meet the WHO standards of physical activity. The study also confirms that secondary education has a positive effect on the public awareness on the role of physical activity in human life. In general, the analysis of the research indicates that there is a relationship between physical activity and some socio-economic factors of the respondents, such as gender, age, education, marital status, income per capita, and the possession of savings. Although the obtained results cannot be applied for the general population, they show some important trends that will be verified in subsequent studies conducted by the authors of the paper.Keywords: International physical activity questionnaire, non-manual workers, physical activity, socio-economic factors, WHO.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12412740 Study of the Effect of Rotation on the Deformation of a Flexible Blade Rotor
Authors: Aref Maalej, Marwa Fakhfakh, Wael Ben Amira
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We present in this work a numerical investigation of fluid-structure interaction to study the elastic behavior of flexible rotors. The principal aim is to provide the effect of the aero/hydrodynamic parameters on the bending deformation of flexible rotors. This study is accomplished using the strong two-way fluid-structure interaction (FSI) developed by the ANSYS Workbench software. This method is used for coupling the fluid solver to the transient structural solver to study the elastic behavior of flexible rotors in water. In this study, we use a moderately flexible rotor modeled by a single blade with simplified rectangular geometry. In this work, we focus on the effect of the rotational frequency on the flapwise bending deformation. It is demonstrated that the blade deforms in the downstream direction and the amplitude of these deformations increases with the rotational frequencies. Also, from a critical frequency, the blade begins to deform in the upstream direction.
Keywords: Numerical simulation, flexible blade, fluid-structure interaction, ANSYS Workbench, flapwise deformation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 932739 Gauteng-s Waste Outlook: A Reflection
Authors: Edison Muzenda
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Gauteng, as the province with the greatest industrial and population density, the economic hub of South Africa also generates the greatest amount of waste, both general and hazardous. Therefore the province has a significant need to develop and apply appropriate integrated waste management policies that ensure that waste is recognised as a serious problem and is managed in an effective integrated manner to preserve both the present and future human health and environment. This paper reflects on Gauteng-s waste outlook in particular the province-s General Waste Minimisation Plan and its Integrated Waste Management Policy. The paper also looks at general waste generation, recyclable waste streams as well as recycling and separation at source initiatives in the province. Both the quantity and nature of solid waste differs considerably across the socio-economic spectrum. People in informal settlements generate an average of 0.16 kg per person per day whereas 2 kg per day is not unusual in affluent areas. For example the amount of waste generated in Johannesburg is approximately 1.2 kg per person per day.
Keywords: General waste, generation, integrated, minimisation, recycling, separation
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14892738 Seasonal Prevalence of Aedes aegypti and Ae.albopictus in Three Topographical Areas of Southern Thailand
Authors: W. Preechaporn, M. Jaroensutasinee, K. Jaroensutasinee
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This study investigated the seasonal prevalence of Aedes aegypti and Ae. albopictus larvae in three topographical areas (i.e. mangrove, rice paddy and mountainous areas). Samples were collected from 300 households in both wet and dry seasons in nine districts in Nakhon Si Thammarat province. Ae. aegypti and Ae. albopictus were found in 21 out of 29 types of water containers in mangrove, rice paddy and mountainous areas. Ae. aegypti and Ae. albopictus laid eggs in different container types depending on season and topographical areas. Ae. aegypti larvae were found most in metal box in mangrove and mountainous areas in wet season. Ae. albopictus larvae were also found most in metal box in mangrove and mountainous areas in both wet and dry seasons. All Ae. albopictus larval indices were higher than Ae. aegypti larval indices in all three topographical areas and both seasons. HI and BI did not differ in three topographical areas but differed between Aedes sp. HI for both Ae. aegypti and Ae. albopictus in all three topographical areas in both seasons were greater than 10 %, except Aedes aegypti in rice paddy area in wet season. This indicated high risks of DHF transmission in these areas.Keywords: Aedes aegypti, Aedes albopictus, Season, Topography.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18012737 Effect of Load Ratio on Probability Distribution of Fatigue Crack Propagation Life in Magnesium Alloys
Authors: Seon Soon Choi
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It is necessary to predict a fatigue crack propagation life for estimation of structural integrity. Because of an uncertainty and a randomness of a structural behavior, it is also required to analyze stochastic characteristics of the fatigue crack propagation life at a specified fatigue crack size. The essential purpose of this study is to find the effect of load ratio on probability distribution of the fatigue crack propagation life at a specified grown crack size and to confirm the good probability distribution in magnesium alloys under various fatigue load ratio conditions. To investigate a stochastic crack growth behavior, fatigue crack propagation experiments are performed in laboratory air under several conditions of fatigue load ratio using AZ31. By Anderson-Darling test, a goodness-of-fit test for probability distribution of the fatigue crack propagation life is performed. The effect of load ratio on variability of fatigue crack propagation life is also investigated.Keywords: Load ratio, fatigue crack propagation life, Magnesium alloys, probability distribution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17142736 Social Assistive Robots, Reframing the Human Robotics Interaction Benchmark of Social Success
Authors: Antonio Espingardeiro
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It is likely that robots will cross the boundaries of industry into households over the next decades. With demographic challenges worldwide, the future ageing populations will require the introduction of assistive technologies capable of providing, care, human dignity and quality of life through the aging process. Robotics technology has a high potential for being used in the areas of social and healthcare by promoting a wide range of activities such as entertainment, companionship, supervision or cognitive and physical assistance. However such close Human Robotics Interaction (HRI) encompass a rich set of ethical scenarios that need to be addressed before Socially Assistive Robots (SARs) reach the global markets. Such interactions with robots may seem a worthy goal for many technical/financial reasons but inevitably require close attention to the ethical dimensions of such interactions. This article investigates the current HRI benchmark of social success. It revises it according to the ethical principles of beneficence, non-maleficence and justice aligned with social care ethos. An extension of such benchmark is proposed based on an empirical study of HRIs conducted with elderly groups.
Keywords: HRI, SARs, Social Success, Benchmark, Elderly care.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20382735 Level of Behavioral Development for Hepatitis C Virus Cases versus Their Contacts: Does Infection Make a Difference and What Is Beyond?
Authors: Ammal M. Metwally, Lobna A. El Etreby, Rehan M. Saleh, Ghada Abdrabou, Somia I. Salama, Amira Orabi, Mohamed Abdelrahman
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Hepatitis C virus infection is a public health threat in Egypt. To control infection, efforts should be spent to encourage healthy behavior. This study aimed to assess the level of behavioral development in order to create a positive environment for the adoption of the recommended behaviors. The study was conducted over one year from Jan. 2011 till Jan. 2012.Knowledge, attitude and behavior of 540 HCV patients and 102 of their contacts were assessed and the level of behavioral development was determined. The study revealed that the majority of patients and contacts knew that HCV infection is dangerous with perceived concern for early diagnosis and treatment. More than 75% knew the correct modes of transmission. The assessment showed positive attitudes towards the recommended practices with intention to adopt those practices. Strategies of creating opportunities to continue the recommended behaviors should be adopted together with the reinforcement of social support.
Keywords: Hepatitis C virus, Level of behavioral development, recommended behaviors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1710