Search results for: QSAR analysis
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 27873

Search results for: QSAR analysis

15363 A Strategy for the Application of Second-Order Monte Carlo Algorithms to Petroleum Exploration and Production Projects

Authors: Obioma Uche

Abstract:

Due to the recent volatility in oil & gas prices as well as increased development of non-conventional resources, it has become even more essential to critically evaluate the profitability of petroleum prospects prior to making any investment decisions. Traditionally, simple Monte Carlo (MC) algorithms have been used to randomly sample probability distributions of economic and geological factors (e.g. price, OPEX, CAPEX, reserves, productive life, etc.) in order to obtain probability distributions for profitability metrics such as Net Present Value (NPV). In recent years, second-order MC algorithms have been shown to offer an advantage over simple MC techniques due to the added consideration of uncertainties associated with the probability distributions of the relevant variables. Here, a strategy for the application of the second-order MC technique to a case study is demonstrated to analyze its effectiveness as a tool for portfolio management.

Keywords: Monte Carlo algorithms, portfolio management, profitability, risk analysis

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15362 Iranian EFL Learners' Attitudes towards Computer Assisted Language Learning (CALL)

Authors: Rose Shayeghi, Pejman Hosseiniun, Ghasem Ghorbanirostam

Abstract:

The present study was conducted to investigate the Iranian EFL learners’ attitudes toward the use of computer technology in language classes as a method of improving English learning. To this end, 120 male and female Iranian learners participated in the study. Instrumentation included a 20-item questionnaire. The analysis of the data revealed that the majority of learners had a positive attitude towards the application of CALL in language classes. Moreover, independent samples t-tests indicated that male participants had a significantly more positive attitude compared with that of the female participants. Finally, the results obtained through ANOVA revealed that the youngest age group had a significantly more positive attitude toward the use of technology in language classes compared to the other age groups.

Keywords: EFL learners, Iranian learners, CALL, language learning

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15361 Fatty Acid Extracts of Sea Pen (Virgularia gustaviana) and Their Potential Applications as Antibacterial, Antifungal, and Anti-Inflammatory Agents

Authors: Sharareh Sharifi

Abstract:

In this study, the crude extracts of Virgularia gustavina were examined as antibacterial, antifungal and anti-inflammatory agent. To assess inflammation, Xylene was applied to the ear of mice. The mice of the experimental group were fed with doses of 10 mg/kg, 20 mg/kg, and 40 mg/kg of lipid extract of chloroform and hexane as a separate group and then statistical analysis was performed on the results. Chloroform and hexane extracts of sea pen have strong anti-inflammatory effects even at low doses which is probably due to 54% arachidonic acid. Antibacterial and antifungal effects of hexane and chloroform extracts were measured with MIC and MBC methods and it is shown that chloroform extract has best activity against Staphylococcus aureus on 125 µg/ml doze in MIC method.

Keywords: sea pen (virgularia gustaviana), lipid extract, anti-inflammatory and anti-bacterial activities, fatty acid

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15360 Structural and Magnetic Properties of CoFe2-xNdxO4 Spinel Ferrite Nanoparticles

Authors: R. S. Yadav, J. Havlica, I. Kuřitka, Z. Kozakova, J. Masilko, M. Hajdúchová, V. Enev, J. Wasserbauer

Abstract:

In this present work, CoFe2-xNdxO4 (0.0 ≤ x ≥0.1) spinel ferrite nanoparticles were synthesized by starch-assisted sol-gel auto-combustion method. Powder X-ray diffraction patterns were revealed the formation of cubic spinel ferrite with the signature of NdFeO3 phase at higher Nd3+ concentration. The field emission scanning electron microscopy study demonstrated the spherical nanoparticle in the size range between 5-15 nm. Raman and Fourier Transform Infrared spectra supported the formation of the spinel ferrite structure in the nanocrystalline form. The X-ray photoelectron spectroscopy (XPS) analysis confirmed the presence of Co2+ and Fe3+ at octahedral as well as a tetrahedral site in CoFe2-xNdxO4 nanoparticles. The change in magnetic properties with a variation of concentration of Nd3+ ions in cobalt ferrite nanoparticles was observed.

Keywords: nanoparticles, spinel ferrites, sol-gel auto-combustion method, CoFe2-xNdxO4

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15359 Validation of a Fluid-Structure Interaction Model of an Aortic Dissection versus a Bench Top Model

Authors: K. Khanafer

Abstract:

The aim of this investigation was to validate the fluid-structure interaction (FSI) model of type B aortic dissection with our experimental results from a bench-top-model. Another objective was to study the relationship between the size of a septectomy that increases the outflow of the false lumen and its effect on the values of the differential of pressure between true lumen and false lumen. FSI analysis based on Galerkin’s formulation was used in this investigation to study flow pattern and hemodynamics within a flexible type B aortic dissection model using boundary conditions from our experimental data. The numerical results of our model were verified against the experimental data for various tear size and location. Thus, CFD tools have a potential role in evaluating different scenarios and aortic dissection configurations.

Keywords: aortic dissection, fluid-structure interaction, in vitro model, numerical

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15358 Thermal Properties of Chitosan-Filled Empty Fruit Bunches Filter Media

Authors: Aziatul Niza Sadikin, Norasikin Othman, Mohd Ghazali Mohd Nawawi, Umi Aisah Asli, Roshafima Rasit Ali, Rafiziana Md Kasmani

Abstract:

Non-woven fibrous filter media from empty fruit bunches were fabricated by using chitosan as a binder. Chitosan powder was dissolved in a 1 wt% aqueous acetic acid and 1 wt% to 4 wt% of chitosan solutions was prepared. Chitosan-filled empty fruit bunches filter media have been prepared via wet-layup method. Thermogravimetric analysis (TGA) was performed to study various thermal properties of the fibrous filter media. It was found that the fibrous filter media have undergone several decomposition stages over a range of temperatures as revealed by TGA thermo-grams, where the temperature for 10% weight loss for chitosan-filled EFB filter media and binder-less filter media was at 150oC and 300oC, Respectively.

Keywords: empty fruit bunches, chitosan, filter media, thermal property

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15357 Theoretical Research for Influence of Irradiation on Transient Creep of Metals

Authors: Pavlo Selyshchev, Tetiana Didenko

Abstract:

Via formalism of the Complex systems and in the framework of the climb - glide model a theoretical approach to describe the influence of irradiation on transient creep of metals. We consider metal under such stress and conditions of irradiation at which creep is determined by dislocation motion that consists in climb and glide. It is shown that there are qualitatively different regimes of a creep as a result of irradiation. Simulation and analysis of this phenomenon are performed. The time dependence of creep rate of metal under an irradiation is theoretically obtained. The conditions of zero minimums of the creep-rate existence as well as the times of their appearance are determined. The changing of the position of creep-rate dips in the conditions of the temperature exposure change is investigated. The obtained results are compared with the experimentally observed dependence of the creep rate on time.

Keywords: creep, climb and glide of dislocations, irradiation, non-linear feed-back, point defects

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15356 Evaluation of Rheological Properties, Anisotropic Shrinkage, and Heterogeneous Densification of Ceramic Materials during Liquid Phase Sintering by Numerical-Experimental Procedure

Authors: Hamed Yaghoubi, Esmaeil Salahi, Fateme Taati

Abstract:

The effective shear and bulk viscosity, as well as dynamic viscosity, describe the rheological properties of the ceramic body during the liquid phase sintering process. The rheological parameters depend on the physical and thermomechanical characteristics of the material such as relative density, temperature, grain size, and diffusion coefficient and activation energy. The main goal of this research is to acquire a comprehensive understanding of the response of an incompressible viscose ceramic material during liquid phase sintering process such as stress-strain relations, sintering and hydrostatic stress, the prediction of anisotropic shrinkage and heterogeneous densification as a function of sintering time by including the simultaneous influence of gravity field, and frictional force. After raw materials analysis, the standard hard porcelain mixture as a ceramic body was designed and prepared. Three different experimental configurations were designed including midpoint deflection, sinter bending, and free sintering samples. The numerical method for the ceramic specimens during the liquid phase sintering process are implemented in the CREEP user subroutine code in ABAQUS. The numerical-experimental procedure shows the anisotropic behavior, the complete difference in spatial displacement through three directions, the incompressibility for ceramic samples during the sintering process. The anisotropic shrinkage factor has been proposed to investigate the shrinkage anisotropy. It has been shown that the shrinkage along the normal axis of casting sample is about 1.5 times larger than that of casting direction, the gravitational force in pyroplastic deformation intensifies the shrinkage anisotropy more than the free sintering sample. The lowest and greatest equivalent creep strain occurs at the intermediate zone and around the central line of the midpoint distorted sample, respectively. In the sinter bending test sample, the equivalent creep strain approaches to the maximum near the contact area with refractory support. The inhomogeneity in Von-Misses, pressure, and principal stress intensifies the relative density non-uniformity in all samples, except in free sintering one. The symmetrical distribution of stress around the center of free sintering sample, cause to hinder the pyroplastic deformations. Densification results confirmed that the effective bulk viscosity was well-defined with relative density values. The stress analysis confirmed that the sintering stress is more than the hydrostatic stress from start to end of sintering time so, from both theoretically and experimentally point of view, the sintering process occurs completely.

Keywords: anisotropic shrinkage, ceramic material, liquid phase sintering process, rheological properties, numerical-experimental procedure

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15355 Diagnose of the Future of Family Businesses Based on the Study of Spanish Family Businesses Founders

Authors: Fernando Doral

Abstract:

Family businesses are a key phenomenon within the business landscape. Nevertheless, it involves two terms (“family” and “business”) which are nowadays rapidly evolving. Consequently, it isn't easy to diagnose if a family business will be a growing or decreasing phenomenon, which is the objective of this study. For that purpose, a sample of 50 Spanish-established companies from various sectors was taken. Different factors were identified for each enterprise, related to the profile of the founders, such as age, the number of sons and daughters, or support received from the family at the moment to start it up. That information was taken as an input for a clustering method to identify groups, which could help define the founders' profiles. That characterization was carried as a base to identify three factors whose evolution should be analyzed: family structures, business landscape and entrepreneurs' motivations. The analysis of the evolution of these three factors seems to indicate a negative tendency of family businesses. Therefore the consequent diagnosis of this study is to consider family businesses as a declining phenomenon.

Keywords: business diagnose, business trends, family business, family business founders

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15354 Implementation of a PDMS Microdevice for the Improved Purification of Circulating MicroRNAs

Authors: G. C. Santini, C. Potrich, L. Lunelli, L. Vanzetti, S. Marasso, M. Cocuzza, C. Pederzolli

Abstract:

The relevance of circulating miRNAs as non-invasive biomarkers for several pathologies is nowadays undoubtedly clear, as they have been found to have both diagnostic and prognostic value able to add fundamental information to patients’ clinical picture. The availability of these data, however, relies on a time-consuming process spanning from the sample collection and processing to the data analysis. In light of this, strategies which are able to ease this procedure are in high demand and considerable effort have been made in developing Lab-on-a-chip (LOC) devices able to speed up and standardise the bench work. In this context, a very promising polydimethylsiloxane (PDMS)-based microdevice which integrates the processing of the biological sample, i.e. purification of extracellular miRNAs, and reverse transcription was previously developed in our lab. In this study, we aimed at the improvement of the miRNA extraction performances of this micro device by increasing the ability of its surface to absorb extracellular miRNAs from biological samples. For this purpose, we focused on the modulation of two properties of the material: roughness and charge. PDMS surface roughness was modulated by casting with several templates (terminated with silicon oxide coated by a thin anti-adhesion aluminum layer), followed by a panel of curing conditions. Atomic force microscopy (AFM) was employed to estimate changes at the nanometric scale. To introduce modifications in surface charge we functionalized PDMS with different mixes of positively charged 3-aminopropyltrimethoxysilanes (APTMS) and neutral poly(ethylene glycol) silane (PEG). The surface chemical composition was characterized by X-ray photoelectron spectroscopy (XPS) and the number of exposed primary amines was quantified with the reagent sulfosuccinimidyl-4-o-(4,4-dimethoxytrityl) butyrate (s-SDTB). As our final end point, the adsorption rate of all these different conditions was assessed by fluorescence microscopy by incubating a synthetic fluorescently-labeled miRNA. Our preliminary analysis identified casting on thermally grown silicon oxide, followed by a curing step at 85°C for 1 hour, as the most efficient technique to obtain a PDMS surface roughness in the nanometric scaleable to trap miRNA. In addition, functionalisation with 0.1% APTMS and 0.9% PEG was found to be a necessary step to significantly increase the amount of microRNA adsorbed on the surface, therefore, available for further steps as on-chip reverse transcription. These findings show a substantial improvement in the extraction efficiency of our PDMS microdevice, ultimately leading to an important step forward in the development of an innovative, easy-to-use and integrated system for the direct purification of less abundant circulating microRNAs.

Keywords: circulating miRNAs, diagnostics, Lab-on-a-chip, polydimethylsiloxane (PDMS)

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15353 Video Based Ambient Smoke Detection By Detecting Directional Contrast Decrease

Authors: Omair Ghori, Anton Stadler, Stefan Wilk, Wolfgang Effelsberg

Abstract:

Fire-related incidents account for extensive loss of life and material damage. Quick and reliable detection of occurring fires has high real world implications. Whereas a major research focus lies on the detection of outdoor fires, indoor camera-based fire detection is still an open issue. Cameras in combination with computer vision helps to detect flames and smoke more quickly than conventional fire detectors. In this work, we present a computer vision-based smoke detection algorithm based on contrast changes and a multi-step classification. This work accelerates computer vision-based fire detection considerably in comparison with classical indoor-fire detection.

Keywords: contrast analysis, early fire detection, video smoke detection, video surveillance

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15352 Historical Analysis of the First Lady of the Silent Screen: Exploring Parallels between Media Portrayals and Fan Letters to Film Star Lillian Gish

Authors: Annette Davies

Abstract:

This paper examines a collection of four fan letters written by two fans to the early film star, Lillian Gish. The letters were sent to Gish between 1929 and 1962 and were later archived at the New York Library of Performing Arts in Manhattan, New York. This paper also analyzes the media's portrayal of Gish during the time period of these written letters in order to identify parallels between the portrayal of Gish in the media and the perception of Gish by her fans, which is espoused in these fan letters. The media analyzed includes newspapers, fan magazines, Paine's 1932 biography Life and Lillian Gish, a film publicity poster for Gish's film Intolerance, and the film roles performed by Gish. Several parallels are found and assessed using the four processes of audience involvement with a media persona-transportation, parasocial interaction, identification, and worship.

Keywords: celebrity, congruency, fan, persona

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15351 Antecedents and Loyalty of Foreign Tourists towards Attractions in Bangkok Metropolitan Area, Thailand

Authors: Arunroong Wongkungwan

Abstract:

This study aimed to investigate the influence of selected antecedents, which were tourists’ satisfaction towards attractions in Bangkok, perceived value of the attractions, feelings of engagement with the attractions, acquaintance with the attractions, push factors, pull factors and motivation to seek novelty, on foreign tourist’s loyalty towards tourist attractions in Bangkok. By using multi stage sampling technique, 400 international tourists were sampled. After that, Semi Structural Equation Model was utilized in the analysis stage by LISREL. The Semi Structural Equation Model of the selected antecedents of tourist’s loyalty attractions had a correlation with the empirical data through the following statistical descriptions: Chi- square = 3.43, df = 4, P- value = 0.48893; RMSEA = 0.000; CFI = 1.00; CN = 1539.75; RMR = 0.0022; GFI = 1.00 and AGFI = 0.98. The findings indicated that all antecedents were able together to predict the loyalty of the foreign tourists who visited Bangkok at 73 percent.

Keywords: antecedent, Bangkok, foreign tourists, loyalty, tourist attractions

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15350 A Method Intensive Top-down Approach for Generating Guidelines for an Energy-Efficient Neighbourhood: A Case of Amaravati, Andhra Pradesh, India

Authors: Rituparna Pal, Faiz Ahmed

Abstract:

Neighbourhood energy efficiency is a newly emerged term to address the quality of urban strata of built environment in terms of various covariates of sustainability. The concept of sustainability paradigm in developed nations has encouraged the policymakers for developing urban scale cities to envision plans under the aegis of urban scale sustainability. The concept of neighbourhood energy efficiency is realized a lot lately just when the cities, towns and other areas comprising this massive global urban strata have started facing a strong blow from climate change, energy crisis, cost hike and an alarming shortfall in the justice which the urban areas required. So this step of urban sustainability can be easily referred more as a ‘Retrofit Action’ which is to cover up the already affected urban structure. So even if we start energy efficiency for existing cities and urban areas the initial layer remains, for which a complete model of urban sustainability still lacks definition. Urban sustainability is a broadly spoken off word with end number of parameters and policies through which the loop can be met. Out of which neighbourhood energy efficiency can be an integral part where the concept and index of neighbourhood scale indicators, block level indicators and building physics parameters can be understood, analyzed and concluded to help emerge guidelines for urban scale sustainability. The future of neighbourhood energy efficiency not only lies in energy efficiency but also important parameters like quality of life, access to green, access to daylight, outdoor comfort, natural ventilation etc. So apart from designing less energy-hungry buildings, it is required to create a built environment which will create less stress on buildings to consume more energy. A lot of literary analysis has been done in the Western countries prominently in Spain, Paris and also Hong Kong, leaving a distinct gap in the Indian scenario in exploring the sustainability at the urban strata. The site for the study has been selected in the upcoming capital city of Amaravati which can be replicated with similar neighbourhood typologies in the area. The paper suggests a methodical intent to quantify energy and sustainability indices in detail taking by involving several macro, meso and micro level covariates and parameters. Several iterations have been made both at macro and micro level and have been subjected to simulation, computation and mathematical models and finally to comparative analysis. Parameters at all levels are analyzed to suggest the best case scenarios which in turn is extrapolated to the macro level finally coming out with a proposal model for energy efficient neighbourhood and worked out guidelines with significance and correlations derived.

Keywords: energy quantification, macro scale parameters, meso scale parameters, micro scale parameters

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15349 Adoption and Diffusion of E-Government Services in India: The Impact of User Demographics and Service Quality

Authors: Sayantan Khanra, Rojers P. Joseph

Abstract:

This study attempts to analyze the impact of demography and service quality on the adoption and diffusion of e-Government services in the context of India. The objective of this paper is to study the users' perception about e-Government services and investigate the key variables that are most salient to the Indian populace. At the completion of this study, a research model that would help to understand the relationship involving the demographic variables and service quality dimensions, and the willingness to adopt e-Government services is expected to be developed. Dedicated authorities, particularly those in developing economies, may use that model or its augmented versions to design and update e-Government services and promote their use among citizens. After all, enhanced public participation is required to improve efficiency, engagement and transparency in the implementation of the aforementioned services.

Keywords: adoption and diffusion of e-government services, demographic variables, hierarchical regression analysis, service quality dimensions

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15348 A Quantitative Analysis of Rural to Urban Migration in Morocco

Authors: Donald Wright

Abstract:

The ultimate goal of this study is to reinvigorate the philosophical underpinnings the study of urbanization with scientific data with the goal of circumventing what seems an inevitable future clash between rural and urban populations. To that end urban infrastructure must be sustainable economically, politically and ecologically over the course of several generations as cities continue to grow with the incorporation of climate refugees. Our research will provide data concerning the projected increase in population over the coming two decades in Morocco, and the population will shift from rural areas to urban centers during that period of time. As a result, urban infrastructure will need to be adapted, developed or built to fit the demand of future internal migrations from rural to urban centers in Morocco. This paper will also examine how past experiences of internally displaced people give insight into the challenges faced by future migrants and, beyond the gathering of data, how people react to internal migration. This study employs four different sets of research tools. First, a large part of this study is archival, which involves compiling the relevant literature on the topic and its complex history. This step also includes gathering data bout migrations in Morocco from public data sources. Once the datasets are collected, the next part of the project involves populating the attribute fields and preprocessing the data to make it understandable and usable by machine learning algorithms. In tandem with the mathematical interpretation of data and projected migrations, this study benefits from a theoretical understanding of the critical apparatus existing around urban development of the 20th and 21st centuries that give us insight into past infrastructure development and the rationale behind it. Once the data is ready to be analyzed, different machine learning algorithms will be experimented (k-clustering, support vector regression, random forest analysis) and the results compared for visualization of the data. The final computational part of this study involves analyzing the data and determining what we can learn from it. This paper helps us to understand future trends of population movements within and between regions of North Africa, which will have an impact on various sectors such as urban development, food distribution and water purification, not to mention the creation of public policy in the countries of this region. One of the strengths of this project is the multi-pronged and cross-disciplinary methodology to the research question, which enables an interchange of knowledge and experiences to facilitate innovative solutions to this complex problem. Multiple and diverse intersecting viewpoints allow an exchange of methodological models that provide fresh and informed interpretations of otherwise objective data.

Keywords: climate change, machine learning, migration, Morocco, urban development

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15347 Theoretical and Experimental Bending Properties of Composite Pipes

Authors: Maja Stefanovska, Svetlana Risteska, Blagoja Samakoski, Gari Maneski, Biljana Kostadinoska

Abstract:

Aim of this work is to determine the theoretical and experimental properties of filament wound glass fiber/epoxy resin composite pipes with different winding design subjected under bending. For determination of bending strength of composite samples three point bending tests were conducted according to ASTM D790 standard. Good correlation between theoretical and experimental results has been obtained, where sample No4 has shown the highest value of bending strength. All samples have demonstrated matrix cracking and fiber failure followed by layers delamination during testing. Also, it was found that smaller winding angles lead to an increase in bending stress. From presented results good merger between glass fibers and epoxy resin was confirmed by SEM analysis.

Keywords: bending properties, composite pipe, winding design, SEM

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15346 Simulation of Die Casting Process in an Industrial Helical Gearbox Flange Die

Authors: Mehdi Modabberifar, Behrouz Raad, Bahman Mirzakhani

Abstract:

Flanges are widely used for connecting valves, pipes and other industrial devices such as gearboxes. Method of producing a flange has a considerable impact on the manner of their involvement with the industrial engines and gearboxes. By Using die casting instead of sand casting and machining for manufacturing flanges, production speed and dimensional accuracy of the parts increases. Also, in die casting, obtained dimensions are close to final dimensions and hence the need for machining flanges after die casting process decreases which makes a significant savings in raw materials and improves the mechanical properties of flanges. In this paper, a typical die of an industrial helical gearbox flange (size ISO 50) was designed and die casting process for producing this type of flange was simulated using ProCAST software. The results of simulation were used for optimizing die design. Finally, using the results of the analysis, optimized die was built.

Keywords: die casting, finite element, flange, helical gearbox

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15345 Simulation and Analytical Investigation of Different Combination of Single Phase Power Transformers

Authors: M. Salih Taci, N. Tayebi, I. Bozkır

Abstract:

In this paper, the equivalent circuit of the ideal single-phase power transformer with its appropriate voltage current measurement was presented. The calculated values of the voltages and currents of the different connections single phase normal transformer and the results of the simulation process are compared. As it can be seen, the calculated results are the same as the simulated results. This paper includes eight possible different transformer connections. Depending on the desired voltage level, step-down and step-up application transformer is considered. Modelling and analysis of a system consisting of an equivalent source, transformer (primary and secondary), and loads are performed to investigate the combinations. The obtained values are simulated in PSpice environment and then how the currents, voltages and phase angle are distributed between them is explained based on calculation.

Keywords: transformer, simulation, equivalent model, parallel series combinations

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15344 Experimental Study and Analysis of Parabolic Trough Collector with Various Reflectors

Authors: Avadhesh Yadav, Balram Manoj Kumar

Abstract:

A solar powered air heating system using parabolic trough collector was experimentally investigated. In this experimental setup, the reflected solar radiations were focused on absorber tube which was placed at focal length of the parabolic trough. In this setup, air was used as working fluid which collects the heat from absorber tube. To enhance the performance of parabolic trough, collector with different type of reflectors were used. It was observed for aluminum sheet maximum temperature is 52.3ºC, which 24.22% more than steel sheet as reflector and 8.5% more than aluminum foil as reflector, also efficiency by using Aluminum sheet as reflector compared to steel sheet as reflector is 61.18% more. Efficiency by using aluminum sheet as reflector compared to aluminum foil as reflector is 18.98% more.

Keywords: parabolic trough collector, reflectors, air flow rates, solar power, aluminum sheet

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15343 Influence of Bragg Reflectors Pairs on Resonance Characteristics of Solidly Mounted Resonators

Authors: Vinita Choudhary

Abstract:

The solidly mounted resonator (SMR) is a bulk acoustic wave-based device consisting of a piezoelectric layer sandwiched between two electrodes upon Bragg reflectors, which then are attached to a substrate. To transform the effective acoustic impedance of the substrate to a near zero value, the Bragg reflectors are composed of alternating high and low acoustic impedance layers of quarter-wavelength thickness. In this work presents the design and investigation of acoustic Bragg reflectors (ABRs) for solidly mounted bulk acoustic wave resonators through analysis and simulation. This performance of the resonator is analyzed using 1D Mason modeling. The performance parameters are the effect of Bragg pairs number on transmissivity, reflectivity, insertion loss, the electromechanical and quality factor of the 5GHz operating resonator.

Keywords: bragg reflectors, SMR, insertion loss, quality factor

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15342 Distorted Digital Mediated Communication: An Analysis of the Effect of Smartphone on Family Communication in Nigeria

Authors: Peter E. Egielewa

Abstract:

Communication through the smartphone connects people globally. However, since the last 10 years, there has been an increasing shift from the social engagement in the family to the digital mediated communication aided by the smartphone. The traditional family communication had largely been oral and relational, which the smartphone is now digitally mediating. The study employs mixed research method of quantitative and qualitative research design and deploys questionnaire to elicit responses from both parents and children of 50 purposively selected families from five villages in Southern Nigeria that are very active with smartphone use. Based on the Theory of Family Systems, preliminary findings show that the smartphone is becoming an addiction among Nigerian family members and has shifted the dynamics of family communication from relational to digital culture. The research concludes that smartphone use affects family communication negatively and recommends the moderation of smartphone use in the family and the search for alternative platforms for family communication that minimises smartphone addiction.

Keywords: digital, distorted communication, family, Nigeria, smartphone

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15341 Analysis of the Barriers and Aids That Lecturers Offer to Students with Disabilities

Authors: Anabel Moriña

Abstract:

In recent years, advances have been made in disability policy at Spanish universities, especially in terms of creating more inclusive learning environments. Nevertheless, while efforts to foster inclusion at the tertiary level -and the growing number of students with disabilities at university- are clear signs of progress, serious barriers to full participation in learning still exist. The research shows that university responses to diversity tend to be reactive, not proactive; as a result, higher education (HE) environments can be especially disabling. It has been demonstrated that the performance of students with disabilities is closely linked to the good will of university faculty and staff. Lectures are key players when it comes to helping or hindering students throughout the teaching/learning process. This paper presents an analysis of how lecturers respond to students with disabilities, the initial question being: do lecturers aid or hinder students? The general aim is to analyse-by listen to the students themselves-lecturers barriers and support identified as affecting academic performance and overall perception of the higher education (HE) experience. Biographical-narrative methodology was employed. This research analysed the results differentiating by fields of knowledge. The research was conducted in two phases: discussion groups along with individual oral/written interviews were set up with 44 students with disabilities and mini life histories were completed for 16 students who participated in the first stage. The study group consisted of students with disabilities enrolled during three academic years. The results of this paper noted that participating students identified many more barriers than bridges when speaking about the role lecturers play in their learning experience. Findings are grouped into several categories: Faculty attitudes when “dealing with” students with disabilities, teaching methodologies, curricular adaptations, and faculty training in working with students. Faculty does not always display appropriate attitudes towards students with disabilities. Study participants speak of them turning their backs on their problems-or behaving in an awkward manner. In many cases, it seems lecturers feel that curricular adaptations of any kind are a form of favouritism. Positive attitudes, however, often depend almost entirely on the good will of faculty and-although well received by students-are hard to come by. As the participants themselves suggest, this study confirms that good teaching practices not only benefit students with disabilities but the student body as a whole. In this sense, inclusive curricula provide new opportunities for all students. A general coincidence has been the lack of training on behalf of lecturers to adequately attend disabled students, and the need to cover this shortage. This can become a primary barrier and is more often due to deficient faculty training than to inappropriate attitudes on the part of lecturers. In conclusion, based on this research we can conclude that more barriers than bridges exist. That said, students do report receiving a good deal of support from their lecturers-although almost exclusively in a spirit of good will; when lecturers do help, however, it tends to have a very positive impact on students' academic performance.

Keywords: barriers, disability, higher education, lecturers

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15340 Simulation Approach for a Comparison of Linked Cluster Algorithm and Clusterhead Size Algorithm in Ad Hoc Networks

Authors: Ameen Jameel Alawneh

Abstract:

A Mobile ad-hoc network (MANET) is a collection of wireless mobile hosts that dynamically form a temporary network without the aid of a system administrator. It has neither fixed infrastructure nor wireless ad hoc sessions. It inherently reaches several nodes with a single transmission, and each node functions as both a host and a router. The network maybe represented as a set of clusters each managed by clusterhead. The cluster size is not fixed and it depends on the movement of nodes. We proposed a clusterhead size algorithm (CHSize). This clustering algorithm can be used by several routing algorithms for ad hoc networks. An elected clusterhead is assigned for communication with all other clusters. Analysis and simulation of the algorithm has been implemented using GloMoSim networks simulator, MATLAB and MAPL11 proved that the proposed algorithm achieves the goals.

Keywords: simulation, MANET, Ad-hoc, cluster head size, linked cluster algorithm, loss and dropped packets

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15339 Investigating the Effect of Groundwater Level on Nailing Arrangement in Excavation Stability

Authors: G. Khamooshian, A. Abbasimoshaei

Abstract:

Different methods are used to stabilize the sticks, among which the method of knitting is commonly used. In recent years, the use of nailing for the stability of excavation has been considered much, which is providing sufficient stability and controlling the structural defects of the guardian, also reduces the cost of the operation. In addition, this method is more prominent in deep excavations than other methods. The purpose of this paper is to investigate the effect of groundwater level and soil type on the length and designing of nails. In this paper, analysis and modeling for vertical arena with constant depth and different levels of groundwater have been done. Also, by changing the soil resistance parameters and design of the nails, an optimum arrangement was made and the effect of changes in groundwater level and soil's type on the design of the nails, the maximum axial force mobilized in the nails and the confidence coefficient for the stability of the groove was examined.

Keywords: excavation, soil effects, nailing, hole analyzing

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15338 Assessment of Genetic Diversity of Iranian Purslane (Portulaca Oleracea L.) Accessions Using ISSR Makers

Authors: Mehdi Mohebodini, Iman Khalili-Baseri, Mehdi Behnamian, Sara Dezhsetan

Abstract:

Diversity analysis at the molecular level using PCR-based markers is the efficient and rapid method of identifying the relationships and differences among the genotypes. In the present study, genetic diversity and relationships among 20 collected purslane accessions were evaluated using ISSR markers. The genotyping data were used to understand the relationships among the collected accessions and identify genetically diverse purslane accessions. The 25 primers gave a total of 92 bands, of which 62 were polymorphic (67.4%). The genetic diversity as estimated by Shannon’s information index was 0.55, revealing a quite high level of genetic diversity in the germplasm. The average number of an observed allele, effective allele, polymorphic information content (PIC) and Nei’s index were 2, 1.65, 0.37 and 0.37, respectively.

Keywords: Portulaca oleracea L., genetic diversity, ISSR, germplasm

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15337 Urban Intensification and the Character of Urban Landscape: A Morphological Perspective

Authors: Xindong An, Kai Gu

Abstract:

Urban intensification is regarded as the prevalent strategy in many cities of the world to ease the pressures of urban sprawl and deliver sustainable development through increasing the density of built form and activities. However, within the context of intensive development, planning and design control measures that help to maintain and promote the character of existing residential environments have been slow to develop. This causes the possible loss of the character of an area that makes a place unique and distinctive. The purpose of this paper is to explore the way of identifying the character of an urban area for the planning of urban landscape in the implementation of intensification. By employing the theory of urban morphology, the concept of morphological region is used for the analysis and characterisation of the spatial structure of the urban landscape in terms of ground plans, building types, and building and land utilisation. The morphological mapping of the character of urban landscape is suggested, which lays a foundation for more sensitive planning of urban landscape changes.

Keywords: character areas, urban intensification, urban morphology, urban landscape

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15336 Spatial Emission of Ions Produced by the APF Plasma Focus Device

Authors: M. Habibi

Abstract:

The angular distribution of ion beam emission from the APF plasma focus device (15kV, 40μf, 115nH) filled with nitrogen gas has been examined through investigating the effect of ion beams on aluminum thin foils in different angular positions. The samples are studied in different distances from the anode end with different shots. The optimum pressure that would be obtained at the applied voltages of 12kV was 0.7 torr. The ions flux declined as the pressure inclined and the maximum ion density at 0.7 torr was about 10.26 × 1022 ions/steradian. The irradiated foils were analyzed with SEM method in order to study their surface and morphological changes. The results of the analysis showed melting and surface evaporation effects and generation of some cracks in the specimens. The result of ion patterns on the samples obtained in this study can be useful in determining ion spatial distributions on the top of anode.

Keywords: plasma focus, spatial distribution, high energy ions, ion angular distribution

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15335 Bank Failures: A Question of Leadership

Authors: Alison L. Miles

Abstract:

Almost all major financial institutions in the world suffered losses due to the financial crisis of 2007, but the extent varied widely. The causes of the crash of 2007 are well documented and predominately focus on the role and complexity of the financial markets. The dominant theme of the literature suggests the causes of the crash were a combination of globalization, financial sector innovation, moribund regulation and short termism. While these arguments are undoubtedly true, they do not tell the whole story. A key weakness in the current analysis is the lack of consideration of those leading the banks pre and during times of crisis. This purpose of this study is to examine the possible link between the leadership styles and characteristics of the CEO, CFO and chairman and the financial institutions that failed or needed recapitalization. As such, it contributes to the literature and debate on international financial crises and systemic risk and also to the debate on risk management and regulatory reform in the banking sector. In order to first test the proposition (p1) that there are prevalent leadership characteristics or traits in financial institutions, an initial study was conducted using a sample of the top 65 largest global banks and financial institutions according to the Banker Top 1000 banks 2014. Secondary data from publically available and official documents, annual reports, treasury and parliamentary reports together with a selection of press articles and analyst meeting transcripts was collected longitudinally from the period 1998 to 2013. A computer aided key word search was used in order to identify the leadership styles and characteristics of the chairman, CEO and CFO. The results were then compared with the leadership models to form a picture of leadership in the sector during the research period. As this resulted in separate results that needed combining, SPSS data editor was used to aggregate the results across the studies using the variables ‘leadership style’ and ‘company financial performance’ together with the size of the company. In order to test the proposition (p2) that there was a prevalent leadership style in the banks that failed and the proposition (P3) that this was different to those that did not, further quantitative analysis was carried out on the leadership styles of the chair, CEO and CFO of banks that needed recapitalization, were taken over, or required government bail-out assistance during 2007-8. These included: Lehman Bros, Merrill Lynch, Royal Bank of Scotland, HBOS, Barclays, Northern Rock, Fortis and Allied Irish. The findings show that although regulatory reform has been a key mechanism of control of behavior in the banking sector, consideration of the leadership characteristics of those running the board are a key factor. They add weight to the argument that if each crisis is met with the same pattern of popular fury with the financier, increased regulation, followed by back to business as usual, the cycle of failure will always be repeated and show that through a different lens, new paradigms can be formed and future clashes avoided.

Keywords: banking, financial crisis, leadership, risk

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15334 Some Discrepancies between Experimentally-Based Theory of Toxic Metals Combined Action and Actual Approaches to Occupational and Environmental Health Risk Assessment and Management

Authors: Ilzira A. Minigalieva

Abstract:

Assessment of cumulative health risks associated with the widely observed combined exposures to two or more metals and their compounds on the organism in industrial or general environment, as well as respective regulatory and technical risk management decision-making have presumably the theoretical and experimental toxicology of mixtures as their reliable scientific basis. Analysis of relevant literature and our own experience proves, however, that there is no full match between these different practices. Moreover, some of the contradictions between them are of a fundamental nature. This unsatisfactory state of things may be explained not only by unavoidable simplifications characteristic of the methodologies of risk assessment and permissible exposure standards setting but also by the extreme intrinsic complexity of the combined toxicity theory, the most essential issues of which are considered and briefly discussed in this paper.

Keywords: toxic metals, nanoparticles, typology of combined toxicity, mathematical modeling, health risk assessment and management

Procedia PDF Downloads 325