Search results for: The effective length factor
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4777

Search results for: The effective length factor

2977 Numerical Study on Parametrical Design of Long Shrouded Contra-Rotating Propulsion System in Hovering

Authors: Chao. Huo, Roger. Barènes, Jérémie. Gressier, Gilles.Grondin

Abstract:

The parametrical study of Shrouded Contra-rotating Rotor was done in this paper based on 2D axisymmetric simulations. The calculations were made with an actuator disk as double rotor model. It objects to explore and quantify the effects of different shroud geometry parameters mainly using the performance of power loading (PL), which could evaluate the whole propulsion system capability as 5 Newtontotal thrust generationfor hover demand. The numerical results show that:The increase of nozzle radius is desired but limited by the flow separation, its optimal design is around 1.15 times rotor radius, the viscosity effects greatly constraint the influence of nozzle shape, the divergent angle around 10.5° performs best for chosen nozzle length;The parameters of inlet such as leading edge curvature, radius and internal shape do not affect thrust great but play an important role in pressure distribution which could produce most part of shroud thrust, they should be chosen according to the reduction of adverse pressure gradients to reduce the risk of boundary separation.

Keywords: Axisymmetric simulation, parametrical design, power loading, Shrouded Contra-Rotating Rotor.

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2976 Plasma Properties Effect on Fluorescent Tube Plasma Antenna Performance

Authors: A. N. Dagang, E. I. Ismail, Z. Zakaria

Abstract:

This paper presents the analysis on the performance of monopole antenna with fluorescent tubes. In this research, the simulation and experimental approach is conducted. The fluorescent tube with different length and size is designed using Computer Simulation Technology (CST) software and the characteristics of antenna parameter are simulated throughout the software. CST was used to simulate antenna parameters such as return loss, resonant frequency, gain and directivity. Vector Network Analyzer (VNA) was used to measure the return loss of plasma antenna in order to validate the simulation results. In the simulation and experiment, the supply frequency is set starting from 1 GHz to 10 GHz. The results show that the return loss of plasma antenna changes when size of fluorescent tubes is varied, correspond to the different plasma properties. It shows that different values of plasma properties such as plasma frequency and collision frequency gives difference result of return loss, gain and directivity. For the gain, the values range from 2.14 dB to 2.36 dB. The return loss of plasma antenna offers higher value range from -22.187 dB to -32.903 dB. The higher the values of plasma frequency and collision frequency, the higher return loss can be obtained. The values obtained are comparative to the conventional type of metal antenna.

Keywords: Plasma antenna, fluorescent tube, computer simulation technology, plasma parameters.

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2975 Control of an Asymmetrical Design of a Pneumatically Actuated Ambidextrous Robot Hand

Authors: Emre Akyürek, Anthony Huynh, Tatiana Kalganova

Abstract:

The Ambidextrous Robot Hand is a robotic device with the purpose to mimic either the gestures of a right or a left hand. The symmetrical behavior of its fingers allows them to bend in one way or another keeping a compliant and anthropomorphic shape. However, in addition to gestures they can reproduce on both sides, an asymmetrical mechanical design with a three tendons routing has been engineered to reduce the number of actuators. As a consequence, control algorithms must be adapted to drive efficiently the ambidextrous fingers from one position to another and to include grasping features. These movements are controlled by pneumatic muscles, which are nonlinear actuators. As their elasticity constantly varies when they are under actuation, the length of pneumatic muscles and the force they provide may differ for a same value of pressurized air. The control algorithms introduced in this paper take both the fingers asymmetrical design and the pneumatic muscles nonlinearity into account to permit an accurate control of the Ambidextrous Robot Hand. The finger motion is achieved by combining a classic PID controller with a phase plane switching control that turns the gain constants into dynamic values. The grasping ability is made possible because of a sliding mode control that makes the fingers adapt to the shape of an object before strengthening their positions.

Keywords: Ambidextrous hand, intelligent algorithms, nonlinear actuators, pneumatic muscles, robotics, sliding control.

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2974 Improvement of Bit-Error-Rate in Optical Fiber Receivers

Authors: Hadj Bourdoucen, Amer Alhabsi

Abstract:

In this paper, a post processing scheme is suggested for improvement of Bit Error-Rate (BER) in optical fiber transmission receivers. The developed scheme has been tested on optical fiber systems operating with a non-return-to-zero (NRZ) format at transmission rates of up to 10Gbps. The transmission system considered is based on well known transmitters and receivers blocks operating at wavelengths in the region of 1550 nm using a standard single mode fiber. Performance of improved detected signals has been evaluated via the analysis of quality factor and computed bit error rates. Numerical simulations have shown a noticeable improvement of the system BER after implementation of the suggested post processing operation on the detected electrical signals.

Keywords: BER improvement, Optical fiber, transmissionperformance, NRZ.

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2973 The Internet of Things Ecosystem: Survey of the Current Landscape, Identity Relationship Management, Multifactor Authentication Mechanisms, and Underlying Protocols

Authors: Nazli W. Hardy

Abstract:

A critical component in the Internet of Things (IoT) ecosystem is the need for secure and appropriate transmission, processing, and storage of the data. Our current forms of authentication, and identity and access management do not suffice because they are not designed to service cohesive, integrated, interconnected devices, and service applications. The seemingly endless opportunities of IoT are in fact circumscribed on multiple levels by concerns such as trust, privacy, security, loss of control, and related issues. This paper considers multi-factor authentication (MFA) mechanisms and cohesive identity relationship management (IRM) standards. It also surveys messaging protocols that are appropriate for the IoT ecosystem.

Keywords: Survey of internet of things ecosystem, protocols, identity relation management, multifactor authentication.

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2972 A Robust Wavelet-Based Watermarking Algorithm Using Edge Detection

Authors: John N. Ellinas

Abstract:

In this paper, a robust watermarking algorithm using the wavelet transform and edge detection is presented. The efficiency of an image watermarking technique depends on the preservation of visually significant information. This is attained by embedding the watermark transparently with the maximum possible strength. The watermark embedding process is carried over the subband coefficients that lie on edges, where distortions are less noticeable, with a subband level dependent strength. Also, the watermark is embedded to selected coefficients around edges, using a different scale factor for watermark strength, that are captured by a morphological dilation operation. The experimental evaluation of the proposed method shows very good results in terms of robustness and transparency to various attacks such as median filtering, Gaussian noise, JPEG compression and geometrical transformations.

Keywords: Watermarking, wavelet transform, edge detection.

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2971 Cable Tension Control and Analysis of Reel Transparency for 6-DOF Haptic Foot Platform on a Cable-Driven Locomotion Interface

Authors: Martin J.-D. Otis, Thien-Ly Nguyen-Dang, Thierry Laliberte, Denis Ouellet, Denis Laurendeau, Clement Gosselin

Abstract:

A Cable-Driven Locomotion Interface provides a low inertia haptic interface and is used as a way of enabling the user to walk and interact with virtual surfaces. These surfaces generate Cartesian wrenches which must be optimized for each motorized reel in order to reproduce a haptic sensation in both feet. However, the use of wrench control requires a measure of the cable tensions applied to the moving platform. The latter measure may be inaccurate if it is based on sensors located near the reel. Moreover, friction hysteresis from the reel moving parts needs to be compensated for with an evaluation of low angular velocity of the motor shaft. Also, the pose of the platform is not known precisely due to cable sagging and mechanical deformation. This paper presents a non-ideal motorized reel design with its corresponding control strategy that aims at overcoming the aforementioned issues. A transfert function of the reel based on frequency responses in function of cable tension and cable length is presented with an optimal adaptative PIDF controller. Finally, an hybrid position/tension control is discussed with an analysis of the stability for achieving a complete functionnality of the haptic platform.

Keywords: haptic, reel, transparency, cable, tension, control

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2970 A Historical Heritage in the Architecture of the South West of Iran, Case Study: Dezfoul City

Authors: Farnaz Nazem

Abstract:

Iranian architects had creative ways for constructing the buildings in each climate. Some of these architectural elements were made under the ground. Shovadan is one of these underground spaces in hot-humid regions in Dezfoul and Shoushtar city that had special functions and characteristics. In this paper some subjects such as the history of Shovadan, its elements and effective factors in the formation of Shovadan in Dezfool city are discussed.

Keywords: Architecture, Dezfoul city, Shovadan, southwest of Iran.

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2969 Highly Scalable, Reversible and Embedded Image Compression System

Authors: Federico Pérez González, Iñaki Goiricelaia Ordorika, Pedro Iriondo Bengoa

Abstract:

A new method for low complexity image coding is presented, that permits different settings and great scalability in the generation of the final bit stream. This coding presents a continuoustone still image compression system that groups loss and lossless compression making use of finite arithmetic reversible transforms. Both transformation in the space of color and wavelet transformation are reversible. The transformed coefficients are coded by means of a coding system in depending on a subdivision into smaller components (CFDS) similar to the bit importance codification. The subcomponents so obtained are reordered by means of a highly configure alignment system depending on the application that makes possible the re-configure of the elements of the image and obtaining different levels of importance from which the bit stream will be generated. The subcomponents of each level of importance are coded using a variable length entropy coding system (VBLm) that permits the generation of an embedded bit stream. This bit stream supposes itself a bit stream that codes a compressed still image. However, the use of a packing system on the bit stream after the VBLm allows the realization of a final highly scalable bit stream from a basic image level and one or several enhance levels.

Keywords: Image compression, wavelet transform, highlyscalable, reversible transform, embedded, subcomponents.

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2968 Smuggling of Migrants as an Influential Factor on National Security, Economic and Social Life

Authors: Jordan Georgiev Deliversky

Abstract:

Human trafficking and smuggling of migrants are criminal activities, which are on the rise over recent years. The number of legal migrants arrived in Europe from outside the European Union are far less than those who want to come and settle in Europe. The objective of this paper is to present the impact on economic and social life of significant measures influencing the smuggling of migrants. The analysis is focused on various complex factors which have multiple origins and are highly influential as regard to the process of migration and the smuggling of migrants. The smuggling of migrants is a criminal activity, directly related to migration. The main results show that often the routes chosen for smuggling of migrants are circuitous, as smugglers carefully avoid strictly controlled roads, checkpoints, and countries or jurisdictions where there is efficiency of justice, with particular emphasis on the law on trafficking of persons and smuggling of migrants.

Keywords: Corruption, migration, security, smuggling.

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2967 Comparative Forensic Analysis of Lipsticks Using Thin Layer Chromatography and Gas Chromatography

Authors: M. O. Ezegbogu, H. B. Osadolor

Abstract:

Lipsticks constitute a significant source of transfer evidence, and can, therefore, provide corroborative or inclusionary evidence in criminal investigation. This study aimed to determine the uniqueness and persistence of different lipstick smears using Thin Layer Chromatography (TLC), and Gas Chromatography with a Flame Ionisation Detector (GC-FID). In this study, we analysed lipstick smears retrieved from tea cups exposed to the environment for up to four weeks. The n-alkane content of each sample was determined using GC-FID, while TLC was used to determine the number of bands, and retention factor of each band per smear. This study shows that TLC gives more consistent results over a 4-week period than GC-FID. It also proposes a maximum exposure time of two weeks for the analysis of lipsticks left in the open using GC-FID. Finally, we conclude that neither TLC nor GC-FID can distinguish lipstick evidence recovered from hypothetical crime scenes.

Keywords: Forensic science, chromatography, identification, lipstick.

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2966 Analysis of Advanced Modulation Format Using Gain and Loss Spectrum for Long Range Radio over Fiber System

Authors: Shaina Nagpal, Amit Gupta

Abstract:

In this work, all optical Stimulated Brillouin Scattering (SBS) generated single sideband with suppressed carrier is presented to provide better efficiency. The generation of single sideband and enhanced carrier power signal using the SBS technique is further used to strengthen the low shifted sideband and to suppress the upshifted sideband. These generated single sideband signals are able to work at high frequency ranges. Also, generated single sideband is validated over 90 km transmission using single mode fiber with acceptable bit error rate. The results for an equivalent are then compared so that the acceptable technique is chosen and also the required quality for the optimum performance of the system is reported.

Keywords: Stimulated Brillouin scattering, radio over fiber, upper side band, quality factor.

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2965 Optimal Planning of Voltage Controlled Distributed Generators for Power Loss Reduction in Unbalanced Distribution Systems

Authors: Mahmoud M. Othman, Yasser G. Hegazy

Abstract:

This paper proposes a novel heuristic algorithm that aims to determine the best size and location of distributed generators in unbalanced distribution networks. The proposed heuristic algorithm can deal with the planning cases where power loss is to be optimized without violating the system practical constraints. The distributed generation units in the proposed algorithm is modeled as voltage controlled node with the flexibility to be converted to constant power factor node in case of reactive power limit violation. The proposed algorithm is implemented in MATLAB and tested on the IEEE 37 -node feeder. The results obtained show the effectiveness of the proposed algorithm.

Keywords: Distributed generation, heuristic approach, Optimization, planning.

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2964 Improvement of Soft Clay Using Floating Cement Dust-Lime Columns

Authors: Adel Belal, Sameh Aboelsoud, Mohy Elmashad, Mohammed Abdelmonem

Abstract:

The two main criteria that control the design and performance of footings are bearing capacity and settlement of soil. In soft soils, the construction of buildings, storage tanks, warehouse, etc. on weak soils usually involves excessive settlement problems. To solve bearing capacity or reduce settlement problems, soil improvement may be considered by using different techniques, including encased cement dust–lime columns. The proposed research studies the effect of adding floating encased cement dust and lime mix columns to soft clay on the clay-bearing capacity. Four experimental tests were carried out. Columns diameters of 3.0 cm, 4.0 cm, and 5.0 cm and columns length of 60% of the clay layer thickness were used. Numerical model was constructed and verified using commercial finite element package (PLAXIS 2D, V8.5). The verified model was used to study the effect of distributing columns around the footing at different distances. The study showed that the floating cement dust lime columns enhanced the clay-bearing capacity with 262%. The numerical model showed that the columns around the footing have a limit effect on the clay improvement.

Keywords: Bearing capacity, cement dust – lime columns, ground improvement, soft clay.

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2963 Numerical Simulation of Heating Characteristics in a Microwave T-Prong Antenna for Cancer Therapy

Authors: M. Chaichanyut, S. Tungjitkusolmun

Abstract:

This research is presented with microwave (MW) ablation by using the T-Prong monopole antennas. In the study, three-dimensional (3D) finite-element methods (FEM) were utilized to analyse: the tissue heat flux, temperature distributions (heating pattern) and volume destruction during MW ablation in liver cancer tissue. The configurations of T-Prong monopole antennas were considered: Three T-prong antenna, Expand T-Prong antenna and Arrow T-Prong antenna. The 3D FEMs solutions were based on Maxwell and bio-heat equations. The microwave power deliveries were 10 W; the duration of ablation in all cases was 300s. Our numerical result, heat flux and the hotspot occurred at the tip of the T-prong antenna for all cases. The temperature distribution pattern of all antennas was teardrop. The Arrow T-Prong antenna can induce the highest temperature within cancer tissue. The microwave ablation was successful when the region where the temperatures exceed 50°C (i.e. complete destruction). The Expand T-Prong antenna could complete destruction the liver cancer tissue was maximized (6.05 cm3). The ablation pattern or axial ratio (Widest/length) of Expand T-Prong antenna and Arrow T-Prong antenna was 1, but the axial ratio of Three T-prong antenna of about 1.15.

Keywords: Liver cancer, T-Prong antenna, Finite element, Microwave ablation.

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2962 Relationship between Criminal Behavior and Mental Illness in Teenagers

Authors: A. Chirita, L. Alexandru, D. Marcoci, C. Ene-Draghici

Abstract:

Minor law breaking seems more and more to be a part of adolescence behavior. An important risk factor which seems to influence delinquency appears to be the socio-economic one. According to Romanian statistics, during the first six months of 2012, 1,378 minors have committed various crimes, the most common being theft, sexual offenses and violent assaults. Drug-related offenses did not reach the gravity of those from high income countries of the European Union, but have a continuous upward during the last years. The aim of our research was to examine whether delinquency in adolescence is correlated to mental disorders or socio-economic and familial factors. Forensic psychiatric expertise was performed to 79 adolescents who committed offenses between 01 January 2012 and 31 December 2012. Teenagers, with ages between 12 and 17, were examined by day hospitalization in the University Clinic of Psychiatry Craiova.

Keywords: Adolescents, criminal behavior, mental illness.

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2961 Mathematical Modeling of Surface Roughness in Surface Grinding Operation

Authors: M.A. Kamely, S.M. Kamil, C.W. Chong

Abstract:

A mathematical model of the surface roughness has been developed by using response surface methodology (RSM) in grinding of AISI D2 cold work tool steels. Analysis of variance (ANOVA) was used to check the validity of the model. Low and high value for work speed and feed rate are decided from design of experiment. The influences of all machining parameters on surface roughness have been analyzed based on the developed mathematical model. The developed prediction equation shows that both the feed rate and work speed are the most important factor that influences the surface roughness. The surface roughness was found to be the lowers with the used of low feed rate and low work speed. Accuracy of the best model was proved with the testing data.

Keywords: Mathematical Modeling, Response surfacemethodology, Surface roughness, Cylindrical Grinding.

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2960 Numerical Investigation of the Flow Characteristics inside the Scrubber Unit

Authors: Kumaresh Selvakumar, Man Young Kim

Abstract:

Wet scrubbers have found widespread use in cleaning contaminated gas streams because of their ability to remove particulates and based on the applications of scrubbing of marine engine exhaust gases by spraying sea-water. In order to examine the flow characteristics inside the scrubber, the model is designated with flow properties of hot air and water sprayer. The flow dynamics of evaporation of hot air by the injection of water droplets is the key factor considered in this paper. The flow behavior inside the scrubber was investigated from the previous works and to sum up the evaporation rate with respect to the concentration of water droplets are predicted to bring out the competent modelling. The numerical analysis using CFD facilitates in understanding the problem better and empathies the behavior of the model over its entire operating envelope.

Keywords: Concentration of water droplets, Evaporation rate, Scrubber, Water sprayer.

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2959 Factors Influencing Students' Self-Concept among Malaysian Students

Authors: Z. Ishak, S. Jamaluddin, F.P Chew

Abstract:

This paper examines the students’ self-concept among 16- and 17- year- old adolescents in Malaysian secondary schools. Previous studies have shown that positive self-concept played an important role in student adjustment and academic performance during schooling. This study attempts to investigate the factors influencing students’ perceptions toward their own self-concept. A total of 1168 students participated in the survey. This study utilized the CoPs (UM) instrument to measure self-concept. Principal Component Analysis (PCA) revealed three factors: academic selfconcept, physical self-concept and social self-concept. This study confirmed that students perceived certain internal context factors, and revealed that external context factor also have an impact on their self-concept.

Keywords: Academic self-concept, physical self-concept, Principal Component Analysis (PCA), social self-concept.

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2958 A Refined Energy-Based Model for Friction-Stir Welding

Authors: Samir A. Emam, Ali El Domiaty

Abstract:

Friction-stir welding has received a huge interest in the last few years. The many advantages of this promising process have led researchers to present different theoretical and experimental explanation of the process. The way to quantitatively and qualitatively control the different parameters of the friction-stir welding process has not been paved. In this study, a refined energybased model that estimates the energy generated due to friction and plastic deformation is presented. The effect of the plastic deformation at low energy levels is significant and hence a scale factor is introduced to control its effect. The predicted heat energy and the obtained maximum temperature using our model are compared to the theoretical and experimental results available in the literature and a good agreement is obtained. The model is applied to AA6000 and AA7000 series.

Keywords: Friction-stir welding, Energy, Aluminum Alloys.

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2957 Accounting for SMEs – How Important is Size in Choosing between Global and Local Standards?

Authors: Cătălin Nicolae Albu, Nadia Albu, Maria Mădălina Gîrbină

Abstract:

There is limited evidence from various countries about the possible impact of various criteria to be used to determine the scope of the IFRS for SMEs issued in 2009 and, research is needed in this area. We provide evidence from Romania, an emerging economy member of the European Union. The aim of this paper is to analyze in a local setting if size is a relevant factor for deciding between local and global standards for SMEs. Our results indicate that size is a moderate indicator of the existence of possible users interested in financial statements and that there is a difference between the scopes of the standard determined on various criteria.. Also, we suggest that the international exposure is quite reduced in the case of SMEs, but is sufficient to suggest that at least some SMEs would benefit from international comparability of financial statements

Keywords: SMEs, IFRS for SMEs, accounting regulation, entity's size.

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2956 Factors Affecting M-Government Deployment and Adoption

Authors: Saif Obaid Alkaabi, Nabil Ayad

Abstract:

Governments constantly seek to offer faster, more secure, efficient and effective services for their citizens. Recent changes and developments to communication services and technologies, mainly due the Internet, have led to immense improvements in the way governments of advanced countries carry out their interior operations Therefore, advances in e-government services have been broadly adopted and used in various developed countries, as well as being adapted to developing countries. The implementation of advances depends on the utilization of the most innovative structures of data techniques, mainly in web dependent applications, to enhance the main functions of governments. These functions, in turn, have spread to mobile and wireless techniques, generating a new advanced direction called m-government. This paper discusses a selection of available m-government applications and several business modules and frameworks in various fields. Practically, the m-government models, techniques and methods have become the improved version of e-government. M-government offers the potential for applications which will work better, providing citizens with services utilizing mobile communication and data models incorporating several government entities. Developing countries can benefit greatly from this innovation due to the fact that a large percentage of their population is young and can adapt to new technology and to the fact that mobile computing devices are more affordable. The use of models of mobile transactions encourages effective participation through the use of mobile portals by businesses, various organizations, and individual citizens. Although the application of m-government has great potential, it does have major limitations. The limitations include: the implementation of wireless networks and relative communications, the encouragement of mobile diffusion, the administration of complicated tasks concerning the protection of security (including the ability to offer privacy for information), and the management of the legal issues concerning mobile applications and the utilization of services.

Keywords: E-government, m-government, system dependability, system security, trust.

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2955 The Hall Coefficient and Magnetoresistance in Rectangular Quantum Wires with Infinitely High Potential under the Influence of a Laser Radiation

Authors: Nguyen Thu Huong, Nguyen Quang Bau

Abstract:

The Hall Coefficient (HC) and the Magnetoresistance (MR) have been studied in two-dimensional systems. The HC and the MR in Rectangular Quantum Wire (RQW) subjected to a crossed DC electric field and magnetic field in the presence of a Strong Electromagnetic Wave (EMW) characterized by electric field are studied in this work. Using the quantum kinetic equation for electrons interacting with optical phonons, we obtain the analytic expressions for the HC and the MR with a dependence on magnetic field, EMW frequency, temperatures of systems and the length characteristic parameters of RQW. These expressions are different from those obtained for bulk semiconductors and cylindrical quantum wires. The analytical results are applied to GaAs/GaAs/Al. For this material, MR depends on the ratio of the EMW frequency to the cyclotron frequency. Indeed, MR reaches a minimum at the ratio 5/4, and when this ratio increases, it tends towards a saturation value. The HC can take negative or positive values. Each curve has one maximum and one minimum. When magnetic field increases, the HC is negative, achieves a minimum value and then increases suddenly to a maximum with a positive value. This phenomenon differs from the one observed in cylindrical quantum wire, which does not have maximum and minimum values.

Keywords: Hall coefficient, rectangular quantum wires, electron-optical phonon interaction, quantum kinetic equation.

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2954 Work and Religion: Artificial Dichotomy or Competing Interests?

Authors: Philip T. Roundy

Abstract:

Prior research has examined the relationship between religiosity, religious involvement, and involvement in secular, civic organizations. However, research has not examined the influence of religious involvement on secular, non-civic organizations (i.e. work organizations). This study examines the link between religiosity, religious involvement, and the three-component model of organizational commitment. More specifically, the author hypothesizes that individuals high in religiosity (and religious involvement) will have lower affective, continuance, and normative commitment than less religious (or non-religious) individuals. In addition, it is hypothesized that this relationship is moderated by a third factor: organizational spirituality. Further, the author hypothesizes that for organizations that are spiritual the negative relationship between religiosity and job commitment will be weakened or even negated.

Keywords: Job Commitment, Organizational Spirituality, Religiosity.

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2953 A Review on Technology Forecasting Methods and Their Application Area

Authors: Daekook Kang, Wooseok Jang, Hyeonjeong Lee, Hyun Joung No

Abstract:

Technology changes have been acknowledged as a critical factor in determining competitiveness of organization. Under such environment, the right anticipation of technology change has been of huge importance in strategic planning. To monitor technology change, technology forecasting (TF) is frequently utilized. In academic perspective, TF has received great attention for a long time. However, few researches have been conducted to provide overview of the TF literature. Even though some studies deals with review of TF research, they generally focused on type and characteristics of various TF, so hardly provides information about patterns of TF research and which TF method is used in certain technology industry. Accordingly, this study profile developments in and patterns of scholarly research in TF over time. Also, this study investigates which technology industries have used certain TF method and identifies their relationships. This study will help in understanding TF research trend and their application area.

Keywords: Technology forecasting, technology industry, TF trend, technology trajectory.

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2952 Static and Dynamical Analysis on Clutch Discs on Different Material and Geometries

Authors: Jairo Aparecido Martins, Estaner Claro Romão

Abstract:

This paper presents the static and cyclic stresses in combination with fatigue analysis resultant of loads applied on the friction discs usually utilized on industrial clutches. The material chosen to simulate the friction discs under load is aluminum. The numerical simulation was done by software COMSOLTM Multiphysics. The results obtained for static loads showed enough stiffness for both geometries and the material utilized. On the other hand, in the fatigue standpoint, failure is clearly verified, what demonstrates the importance of both approaches, mainly dynamical analysis. The results and the conclusion are based on the stresses on disc, counted stress cycles, and fatigue usage factor.

Keywords: Aluminum, industrial clutch, static and dynamic loading, numerical simulation.

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2951 Towards a Framework for Embedded Weight Comparison Algorithm with Business Intelligence in the Plantation Domain

Authors: M. Pushparani, A. Sagaya

Abstract:

Embedded systems have emerged as important elements in various domains with extensive applications in automotive, commercial, consumer, healthcare and transportation markets, as there is emphasis on intelligent devices. On the other hand, Business Intelligence (BI) has also been extensively used in a range of applications, especially in the agriculture domain which is the area of this research. The aim of this research is to create a framework for Embedded Weight Comparison Algorithm with Business Intelligence (EWCA-BI). The weight comparison algorithm will be embedded within the plantation management system and the weighbridge system. This algorithm will be used to estimate the weight at the site and will be compared with the actual weight at the plantation. The algorithm will be used to build the necessary alerts when there is a discrepancy in the weight, thus enabling better decision making. In the current practice, data are collected from various locations in various forms. It is a challenge to consolidate data to obtain timely and accurate information for effective decision making. Adding to this, the unstable network connection leads to difficulty in getting timely accurate information. To overcome the challenges embedding is done on a portable device that will have the embedded weight comparison algorithm to also assist in data capture and synchronize data at various locations overcoming the network short comings at collection points. The EWCA-BI will provide real-time information at any given point of time, thus enabling non-latent BI reports that will provide crucial information to enable efficient operational decision making. This research has a high potential in bringing embedded system into the agriculture industry. EWCA-BI will provide BI reports with accurate information with uncompromised data using an embedded system and provide alerts, therefore, enabling effective operation management decision-making at the site.

Keywords: Embedded business intelligence, weight comparison algorithm, oil palm plantation, embedded systems.

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2950 Some Issues with Extension of an HPC Cluster

Authors: Pil Seong Park

Abstract:

Homemade HPC clusters are widely used in many small labs, because they are easy to build and cost-effective. Even though incremental growth is an advantage of clusters, it results in heterogeneous systems anyhow. Instead of adding new nodes to the cluster, we can extend clusters to include some other Internet servers working independently on the same LAN, so that we can make use of their idle times, especially during the night. However extension across a firewall raises some security problems with NFS. In this paper, we propose a method to solve such a problem using SSH tunneling, and suggest a modified structure of the cluster that implements it.

Keywords: Extension of HPC clusters, Security, NFS, SSH tunneling.

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2949 Numerical Investigation of Natural Convection of Pine, Olive, and Orange Leaves

Authors: Ali Reza Tahavvor, Saeed Hosseini, Nazli Jowkar, Behnam Amiri

Abstract:

Heat transfer of leaves is a crucial factor in optimal operation of metabolic functions in plants. In order to quantify this phenomenon in different leaves and investigate the influence of leaf shape on heat transfer, natural convection for pine, orange and olive leaves was simulated as representatives of different groups of leaf shapes. CFD techniques were used in this simulation with the purpose to calculate heat transfer of leaves in similar environmental conditions. The problem was simulated for steady state and threedimensional conditions. From obtained results, it was concluded that heat fluxes of all three different leaves are almost identical, however, total rate of heat transfer have highest and lowest values for orange leaves, and pine leaves, respectively.

Keywords: Computational fluid dynamic, heat flux, heat transfer, natural convection.

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2948 High Gain Mobile Base Station Antenna Using Curved Woodpile EBG Technique

Authors: P. Kamphikul, P. Krachodnok, R. Wongsan

Abstract:

This paper presents the gain improvement of a sector antenna for mobile phone base station by using the new technique to enhance its gain for microstrip antenna (MSA) array without construction enlargement. The curved woodpile Electromagnetic Band Gap (EBG) has been utilized to improve the gain instead. The advantages of this proposed antenna are reducing the length of MSAs array but providing the higher gain and easy fabrication and installation. Moreover, it provides a fan-shaped radiation pattern, wide in the horizontal direction and relatively narrow in the vertical direction, which appropriate for mobile phone base station. The paper also presents the design procedures of a 1x8 MSAs array associated with U-shaped reflector for decreasing their back and side lobes. The fabricated curved woodpile EBG exhibits bandgap characteristics at 2.1 GHz and is utilized for realizing a resonant cavity of MSAs array. This idea has been verified by both the Computer Simulation Technology (CST) software and experimental results. As the results, the fabricated proposed antenna achieves a high gain of 20.3 dB and the half-power beam widths in the E- and H-plane of 36.8 and 8.7 degrees, respectively. Good qualitative agreement between measured and simulated results of the proposed antenna was obtained.

Keywords: Gain Improvement, Microstrip Antenna Array, Electromagnetic Band Gap, Base Station.

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