Search results for: field effect transistors
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6607

Search results for: field effect transistors

6097 Experimental Analysis of Mechanical Behavior under the Effect of Temperature Frequency

Authors: A. Nedjar, S. Aguib, M. Meloussi, T. Djedid, A. Khebli, R. Harhout, L. Kobzili, N. Chikh, M. Tourab

Abstract:

Finding the mechanical properties of magnetorheological elastomers (MREs) is fundamental to create smart materials and devices with desired properties and functionalities. The MREs properties, in shear mode, have been extensively investigated, but these have been less exploited with frequency-temperature dependence. In this article, we studied the performance of MREs with frequency-temperature dependence. The elastic modulus, loss modulus and loss factor of MREs were studied under different temperature values; different values of the magnetic field and different values of the frequency. The results found showed the interest of these active materials in different industrial sectors.

Keywords: Magnetorheological elastomer, mechanical behavior, frequency, temperature.

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6096 Unsteady MHD Flow of an Incompressible Elastico-Viscous Fluid in a Tube of Spherical Cross Section on a Porous Boundary

Authors: Sanjay Baburao Kulkarni

Abstract:

Exact solution of an unsteady MHD flow of elasticoviscous fluid through a porous media in a tube of spherical cross section under the influence of magnetic field and constant pressure gradient has been obtained in this paper. Initially, the flow is generated by a constant pressure gradient. After attaining the steady state, the pressure gradient is suddenly withdrawn and the resulting fluid motion in a tube of spherical cross section by taking into account of the porosity factor and magnetic parameter of the bounding surface is investigated. The problem is solved in two-stages the first stage is a steady motion in tube under the influence of a constant pressure gradient, the second stage concern with an unsteady motion. The problem is solved employing separation of variables technique. The results are expressed in terms of a non-dimensional porosity parameter (K), magnetic parameter (m) and elasticoviscosity parameter (β), which depends on the Non-Newtonian coefficient. The flow parameters are found to be identical with that of Newtonian case as elastic-viscosity parameter and magnetic parameter tends to zero and porosity tends to infinity. It is seen that the effect of elastico-viscosity parameter, porosity parameter and magnetic parameter of the bounding surface has significant effect on the velocity parameter.

Keywords: Elastico-viscous fluid, Porous media, Second order fluids, Spherical cross-section, Magnetic parameter.

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6095 Cryptocurrency-Based Mobile Payments with Near-Field Communication-Enabled Devices

Authors: Marko Niinimaki

Abstract:

Cryptocurrencies are getting increasingly popular, but very few of them can be conveniently used in daily mobile phone purchases. To solve this problem, we demonstrate how to build a functional prototype of a mobile cryptocurrency-based e-commerce application the communicates with Near-Field Communication (NFC) tags. Using the system, users are able to purchase physical items with an NFC tag that contains an e-commerce URL. The payment is done simply by touching the tag with a mobile device and accepting the payment. Our method is constructive: we describe the design and technologies used in the implementation and evaluate the security and performance of the solution. Our main finding is that the analysis and measurements show that our solution is feasible for e-commerce.

Keywords: Cryptocurrency, e-commerce, NFC, mobile devices.

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6094 Effect of Isfahan Refinery, Power Plant and Petrochemical on Borkhar District Soil

Authors: A. Gandomkar

Abstract:

This study aimed to evaluate regional soil Borkhar of the metals Lead has been made. In this field study fires visits to the regions. The limit of this study located in the East refineries, petrochemical and power plant to 20 km was selected. The 41 soil samples from depths of 0 to 10 cm in area and were randomized. Soil samples were transported to the laboratory and by air was dry and passed through 2-mil thickness sieve. In the laboratory of physical and chemical characteristics and concentrations of total absorption was measured. The results showed that the amount of lead in soil in many parts of the range higher than the standard limit. Survey maps show that the lead spatial distribution of the region does not special pattern.

Keywords: Soil Pollution, Heavy Metals, Borkhar District, Soil Sampling.

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6093 A System Functions Set-Up through Near Field Communication of a Smartphone

Authors: Jaemyoung Lee

Abstract:

We present a method to set up system functions through a near filed communication (NFC) of a smartphone. The short communication distance of the NFC which is usually less than 4 cm could prevent any interferences from other devices and establish a secure communication channel between a system and the smartphone. The proposed set-up method for system function values is demonstrated for a blacbox system in a car. In demonstration, system functions of a blackbox which is manipulated through NFC of a smartphone are controls of image quality, sound level, shock sensing level to store images, etc. The proposed set-up method for system function values can be used for any devices with NFC.

Keywords: System set-up, near field communication, smartphone, Android.

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6092 The Study on the Relationship between Momentum Profits and Psychological Factors: Evidence from Taiwan

Authors: Chih-Hsiang Chang

Abstract:

This study provides insight into the effects of investor sentiment, excess optimism, overconfidence, the disposition effect, and herding formation on momentum profits. This study contributes to the field by providing a further examination of the relationship between psychological factors and momentum profits. The empirical results show that there is no evidence of significant momentum profits in Taiwan’s stock market. Additionally, investor sentiment in Taiwan’s stock market significantly influences its momentum profits.

Keywords: Momentum profits, psychological factors, herding formation, investor sentiment.

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6091 On the Prediction of Transmembrane Helical Segments in Membrane Proteins

Authors: Yu Bin, Zhang Yan

Abstract:

The prediction of transmembrane helical segments (TMHs) in membrane proteins is an important field in the bioinformatics research. In this paper, a method based on discrete wavelet transform (DWT) has been developed to predict the number and location of TMHs in membrane proteins. PDB coded as 1F88 was chosen as an example to describe the prediction of the number and location of TMHs in membrane proteins by using this method. One group of test data sets that contain total 19 protein sequences was utilized to access the effect of this method. Compared with the prediction results of DAS, PRED-TMR2, SOSUI, HMMTOP2.0 and TMHMM2.0, the obtained results indicate that the presented method has higher prediction accuracy.

Keywords: hydrophobicity, membrane protein, transmembranehelical segments, wavelet transform

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6090 Positive Periodic Solutions in a Discrete Competitive System with the Effect of Toxic Substances

Authors: Changjin Xu, Qianhong Zhang

Abstract:

In this paper, a delayed competitive system with the effect of toxic substances is investigated. With the aid of differential equations with piecewise constant arguments, a discrete analogue of continuous non-autonomous delayed competitive system with the effect of toxic substances is proposed. By using Gaines and Mawhin,s continuation theorem of coincidence degree theory, a easily verifiable sufficient condition for the existence of positive solutions of difference equations is obtained.

Keywords: Competitive system, periodic solution, discrete time delay, topological degree.

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6089 Lorentz Forces in the Container

Authors: K. Horáková, K. Fraňa

Abstract:

Leading topic of this article is description of Lorentz forces in the container with cuboid and cylindrical shape. Inside of the container is an electrically conductive melt. This melt is driven by rotating magnetic field. Input data for comparing Lorentz forces in the container with cuboid shape were obtained from the computing program NS-FEM3D, which uses DDS method of computing. Values of Lorentz forces for container with cylindrical shape were obtained from inferred analytical formula.

Keywords: Lorentz forces, magnetohydrodynamics, rotatingmagnetic field, computing program NS-FEM3D

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6088 Histopathological and Morphological Defects in the Mice Prenatally Exposed to Low EMF

Authors: Y. Rosli, A. Husna AH, M. Nurhayati

Abstract:

This research was carried out to determine the possible effects of low electromagnetic field (EMF) exposure to the developing mice fetuses. Pregnant mice were exposed to EMF exposure at 0mT (sham) and 1.2 mT for six hours per session, carried out on gestation day 3, 6, 9, 12 and 15. Samples from the stillborn offspring were observed for morphological defects. The heart didn-t show progressive cellular damage, the lungs were congested and emphysemics. The bones were in advance stage of hypertrophy. Spectrums of morphological defects were observed over 70% of the surviving offspring. These results indicate that even at lower exposure to low EMF, is enough to induce morphological defects in prenatal mice.

Keywords: bone hypertrophy, EMF, low electromagnetic field.

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6087 Determination of Unsaturated Soil Permeability Based on Geometric Factor Development of Constant Discharge Model

Authors: A. Rifa’i, Y. Takeshita, M. Komatsu

Abstract:

After Yogyakarta earthquake in 2006, the main problem that occurred in the first yard of Prambanan Temple is ponding area that occurred after rainfall. Soil characterization needs to be determined by conducting several processes, especially permeability coefficient (k) in both saturated and unsaturated conditions to solve this problem. More accurate and efficient field testing procedure is required to obtain permeability data that present the field condition. One of the field permeability test equipment is Constant Discharge procedure to determine the permeability coefficient. Necessary adjustments of the Constant Discharge procedure are needed to be determined especially the value of geometric factor (F) to improve the corresponding value of permeability coefficient. The value of k will be correlated with the value of volumetric water content (θ) of an unsaturated condition until saturated condition. The principle procedure of Constant Discharge model provides a constant flow in permeameter tube that flows into the ground until the water level in the tube becomes constant. Constant water level in the tube is highly dependent on the tube dimension. Every tube dimension has a shape factor called the geometric factor that affects the result of the test. Geometric factor value is defined as the characteristic of shape and radius of the tube. This research has modified the geometric factor parameters by using empty material tube method so that the geometric factor will change. Saturation level is monitored by using soil moisture sensor. The field test results were compared with the results of laboratory tests to validate the results of the test. Field and laboratory test results of empty tube material method have an average difference of 3.33 x 10-4 cm/sec. The test results showed that modified geometric factor provides more accurate data. The improved methods of constant discharge procedure provide more relevant results.

Keywords: Constant discharge, geometric factor, permeability coefficient, unsaturated soils.

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6086 Optimization and Determination of Process Parameters in Thin Film SOI Photo-BJMOSFET

Authors: Hai-Qing Xie, Yun Zeng, Yong-Hong Yan, Guo-Liang Zhang, Tai-Hong Wang

Abstract:

We propose photo-BJMOSFET (Bipolar Junction Metal-Oxide-Semiconductor Field Effect Transistor) fabricated on SOI film. ITO film is adopted in the device as gate electrode to reduce light absorption. I-V characteristics of photo-BJMOSFET obtained in dark (dark current) and under 570nm illumination (photo current) are studied furthermore to achieve high photo-to-dark-current contrast ratio. Two variables in the calculation were the channel length and the thickness of the film which were set equal to six different values, i.e., L=2, 4, 6, 8, 10, and 12μm and three different values, i.e., dsi =100, 200 and 300nm, respectively. The results indicate that the greatest photo-to-dark-current contrast ratio is achieved with L=10μm and dsi=200 nm at VGK=0.6V.

Keywords: Photo-to-dark-current contrast ratio, Photo-current, Dark-current, Process parameter

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6085 Evaluation of Curriculum Quality of Postgraduate Studies of Actuarial Science Field at Public Universities of Iran

Authors: F. Havas Beigi, M. Vafaee Yeganeh, E. Mohammadi

Abstract:

Evaluation and survey of curriculum quality as one of the most important components of universities system is necessary for different levels in higher education. The main purpose of this study was to survey of the curriculum quality of Actuarial science field. Case: University of SHahid Beheshti and Higher education institute of Eco insurance (according to viewpoint of students, alumni, employers and faculty members). Descriptive statistics (mean, tables, percentage, and frequency distribution) and inferential statistics (CHI SQUARE) were used to analyze the data. Six criteria considered for the Quality of curriculum: objectives, content, teaching and learning methods, space and facilities, Time, assessment of learning. Content, teaching and learning methods, space and facilities, assessment of learning criteria were relatively desirable level, objectives and time criterions were desirable level. The quality of curriculum of Actuarial Science field was relatively desirable level.

Keywords: Quality, curriculum, Actuarial science, higher education

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6084 Effect of Endplate Shape on Performance and Stability of Wings-in Ground (WIG) Craft

Authors: Kyoungwoo Park, Chol Ho Hong, Kwang Soo Kim, Juhee Lee

Abstract:

Numerical analysis for the aerodynamic characteristics of the WIG (wing-in ground effect) craft with highly cambered and aspect ratio of one is performed to predict the ground effect for the case of with- and without- lower-extension endplate. The analysis is included varying angles of attack from 0 to10 deg. and ground clearances from 5% of chord to 50%. Due to the ground effect, the lift by rising in pressure on the lower surface is increased and the influence of wing-tip vortices is decreased. These two significant effects improve the lift-drag ratio. On the other hand, the endplate prevents the high-pressure air escaping from the air cushion at the wing tip and causes to increase the lift and lift-drag ratio further. It is found from the visualization of computation results that two wing-tip vortices are generated from each surface of the wing tip and their strength are weak and diminished rapidly. Irodov-s criteria are also evaluated to investigate the static height stability. The comparison of Irodov-s criteria shows that the endplate improves the deviation of the static height stability with respect to pitch angles and heights. As the results, the endplate can improve the aerodynamic characteristics and static height stability of wings in ground effect, simultaneously.

Keywords: WIG craft, Endplate, Ground Effect, Aerodynamics, CFD, Lift-drag ratio, Static height stability.

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6083 Virtual Assembly in a Semi-Immersive Environment

Authors: Emad S. Abouel Nasr, Abdulaziz M. El-Tamimi, Mustufa H. Abidi, Abdulrahman M. Al-Ahmari

Abstract:

Virtual Assembly (VA) is one of the key technologies in advanced manufacturing field. It is a promising application of virtual reality in design and manufacturing field. It has drawn much interest from industries and research institutes in the last two decades. This paper describes a process for integrating an interactive Virtual Reality-based assembly simulation of a digital mockup with the CAD/CAM infrastructure. The necessary hardware and software preconditions for the process are explained so that it can easily be adopted by non VR experts. The article outlines how assembly simulation can improve the CAD/CAM procedures and structures; how CAD model preparations have to be carried out and which virtual environment requirements have to be fulfilled. The issue of data transfer is also explained in the paper. The other challenges and requirements like anti-aliasing and collision detection have also been explained. Finally, a VA simulation has been carried out for a ball valve assembly and a car door assembly with the help of Vizard virtual reality toolkit in a semi-immersive environment and their performance analysis has been done on different workstations to evaluate the importance of graphical processing unit (GPU) in the field of VA.

Keywords: Collision Detection, Graphical Processing Unit (GPU), Virtual Reality (VR), Virtual Assembly (VA).

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6082 Numerical Analysis of Flow through Abrasive Water Suspension Jet: The Effect of Garnet, Aluminum Oxide and Silicon Carbide Abrasive on Skin Friction Coefficient Due To Wall Shear and Jet Exit Kinetic Energy

Authors: Deepak D, Anjaiah D, Yagnesh Sharma N.

Abstract:

It is well known that the abrasive particles in the abrasive water suspension has significant effect on the erosion characteristics of the inside surface of the nozzle. Abrasive particles moving with the flow cause severe skin friction effect, there by altering the nozzle diameter due to wear which in turn reflects on the life of the nozzle for effective machining. Various commercial abrasives are available for abrasive water jet machining. The erosion characteristic of each abrasive is different. In consideration of this aspect, in the present work, the effect of abrasive materials namely garnet, aluminum oxide and silicon carbide on skin friction coefficient due to wall shear stress and jet kinetic energy has been analyzed. It is found that the abrasive material of lower density produces a relatively higher skin friction effect and higher jet exit kinetic energy.

Keywords: Abrasive water suspension jet, Skin friction coefficient, Jet kinetic energy, Particulate loading, Stokes number.

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6081 Evaluations of 3D Concrete Printing Produced in the Environment of United Arab Emirates

Authors: Adil K. Tamimi, Tarig Ali, Rawan Anoohi, Ahmed Rajput, Kaltham Alkamali

Abstract:

3D concrete printing is one of the most innovative and modern techniques in the field of construction that achieved several milestones in that field for the following advantages: saving project’s time, ability to execute complicated shapes, reduce waste and low cost. However, the concept of 3D printing in UAE is relatively new where construction teams, including clients, consultants, and contractors, do not have the required knowledge and experience in the field. This is the most significant obstacle for the construction parties, which make them refrained from using 3D concrete printing compared to conventional concreting methods. This study shows the historical development of the 3D concrete printing, its advantages, and the challenges facing this innovation. Concrete mixes and materials have been proposed and evaluated to select the best combination for successful 3D concrete printing. The main characteristics of the 3D concrete printing in the fresh and hardened states are considered, such as slump test, flow table, compressive strength, tensile, and flexural strengths. There is need to assess the structural stability of the 3D concrete by testing the bond between interlayers of the concrete.  

Keywords: 3D printing, concrete mixes, workability, compressive strength, slump test, tensile strength, flexural strength.

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6080 Formation of (Ga,Mn)N Dilute Magnetic Semiconductor by Manganese Ion Implantation

Authors: N.S. Pradhan, S.K. Dubey, A. D.Yadav, Arvind Singh, D.C. Kothari

Abstract:

Un-doped GaN film of thickness 1.90 mm, grown on sapphire substrate were uniformly implanted with 325 keV Mn+ ions for various fluences varying from 1.75 x 1015 - 2.0 x 1016 ions cm-2 at 3500 C substrate temperature. The structural, morphological and magnetic properties of Mn ion implanted gallium nitride samples were studied using XRD, AFM and SQUID techniques. XRD of the sample implanted with various ion fluences showed the presence of different magnetic phases of Ga3Mn, Ga0.6Mn0.4 and Mn4N. However, the compositions of these phases were found to be depended on the ion fluence. AFM images of non-implanted sample showed micrograph with rms surface roughness 2.17 nm. Whereas samples implanted with the various fluences showed the presence of nano clusters on the surface of GaN. The shape, size and density of the clusters were found to vary with respect to ion fluence. Magnetic moment versus applied field curves of the samples implanted with various fluences exhibit the hysteresis loops. The Curie temperature estimated from zero field cooled and field cooled curves for the samples implanted with the fluence of 1.75 x 1015, 1.5 x 1016 and 2.0 x 1016 ions cm-2 was found to be 309 K, 342 K and 350 K respectively.

Keywords: GaN, Ion implantation, XRD, AFM, SQUID

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6079 Simulating Gradient Contour and Mesh of a Scalar Field

Authors: Usman Ali Khan, Bismah Tariq, Khalida Raza, Saima Malik, Aoun Muhammad

Abstract:

This research paper is based upon the simulation of gradient of mathematical functions and scalar fields using MATLAB. Scalar fields, their gradient, contours and mesh/surfaces are simulated using different related MATLAB tools and commands for convenient presentation and understanding. Different mathematical functions and scalar fields are examined here by taking their gradient, visualizing results in 3D with different color shadings and using other necessary relevant commands. In this way the outputs of required functions help us to analyze and understand in a better way as compared to just theoretical study of gradient.

Keywords: MATLAB, Gradient, Contour, Scalar Field, Mesh

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6078 Classic and Heuristic Approaches in Robot Motion Planning A Chronological Review

Authors: Ellips Masehian, Davoud Sedighizadeh

Abstract:

This paper reviews the major contributions to the Motion Planning (MP) field throughout a 35-year period, from classic approaches to heuristic algorithms. Due to the NP-Hardness of the MP problem, heuristic methods have outperformed the classic approaches and have gained wide popularity. After surveying around 1400 papers in the field, the amount of existing works for each method is identified and classified. Especially, the history and applications of numerous heuristic methods in MP is investigated. The paper concludes with comparative tables and graphs demonstrating the frequency of each MP method's application, and so can be used as a guideline for MP researchers.

Keywords: Robot motion planning, Heuristic algorithms.

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6077 Attenuation in Transferred RF Power to a Biomedical Implant due to the Misalignment Coils

Authors: Batel Noureddine, Mehenni Mohamed, Dekar Lies

Abstract:

In biomedical implant field, a new formula is given for the study of Radio Frequency power attenuation by simultaneous effects of side and angular misalignment of the supply/data transfer coils. A confrontation with the practical measurements done into a Faraday cage, allowed a checking of the obtained theoretical results. The DC supply systems without material connection and the data transmitters used in the case of biomedical implants, can be well dimensioned by taking into account the possibility of power attenuation by misalignment of transfer coils

Keywords: Biomedical implant field, misalignment coils, powerattenuation, transmitter and receiver coils.

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6076 Study of the Effect of Soil Compaction and Height on Pipe Ovality for Buried Steel Pipe

Authors: Ali Ghodsbin Jahromi, Ehsan Moradi

Abstract:

In this paper, the numerical study of buried steel pipe in soil is investigated. Buried pipeline under soil weight, after embankment on the pipe leads to ovality of pipe. In this paper also it is considered the percentage of soil compaction, the soil height on the steel pipe and the external load of a mechanical excavator on the steel pipe and finally, the effect of these on the rate of pipe ovality investigated. Furthermore, the effect of the pipes’ thickness on ovality has been investigated. The results show that increasing the percentage of soil compaction has more effect on reducing percentage of ovality, and if the percentage of soil compaction increases, we can use the pipe with less thickness. Finally, ovality rate of the pipe and acceptance criteria of pipe diameter up to yield stress is investigated.

Keywords: Pipe ovality, soil compaction, finite element, pipe thickness.

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6075 Automatic Building an Extensive Arabic FA Terms Dictionary

Authors: El-Sayed Atlam, Masao Fuketa, Kazuhiro Morita, Jun-ichi Aoe

Abstract:

Field Association (FA) terms are a limited set of discriminating terms that give us the knowledge to identify document fields which are effective in document classification, similar file retrieval and passage retrieval. But the problem lies in the lack of an effective method to extract automatically relevant Arabic FA Terms to build a comprehensive dictionary. Moreover, all previous studies are based on FA terms in English and Japanese, and the extension of FA terms to other language such Arabic could be definitely strengthen further researches. This paper presents a new method to extract, Arabic FA Terms from domain-specific corpora using part-of-speech (POS) pattern rules and corpora comparison. Experimental evaluation is carried out for 14 different fields using 251 MB of domain-specific corpora obtained from Arabic Wikipedia dumps and Alhyah news selected average of 2,825 FA Terms (single and compound) per field. From the experimental results, recall and precision are 84% and 79% respectively. Therefore, this method selects higher number of relevant Arabic FA Terms at high precision and recall.

Keywords: Arabic Field Association Terms, information extraction, document classification, information retrieval.

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6074 Effect of Dynamic Stall, Finite Aspect Ratio and Streamtube Expansion on VAWT Performance Prediction using the BE-M Model

Authors: M. Raciti Castelli, A. Fedrigo, E. Benini

Abstract:

A multiple-option analytical model for the evaluation of the energy performance and distribution of aerodynamic forces acting on a vertical-axis Darrieus wind turbine depending on both rotor architecture and operating conditions is presented. For this purpose, a numerical algorithm, capable of generating the desired rotor conformation depending on design geometric parameters, is coupled to a Single/Double-Disk Multiple-Streamtube Blade Element – Momentum code. Both single and double-disk configurations are analyzed and model predictions are compared to literature experimental data in order to test the capability of the code for predicting rotor performance. Effective airfoil characteristics based on local blade Reynolds number are obtained through interpolation of literature low-Reynolds airfoil databases. Some corrections are introduced inside the original model with the aim of simulating also the effects of blade dynamic stall, rotor streamtube expansion and blade finite aspect ratio, for which a new empirical relationship to better fit the experimental data is proposed. In order to predict also open field rotor operation, a freestream wind shear profile is implemented, reproducing the effect of atmospheric boundary layer.

Keywords: Wind turbine, BE-M, dynamic stall, streamtube expansion, airfoil finite aspect ratio

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6073 A National Survey of Clinical Psychology Graduate Student Attitudes toward Psychotherapy Treatment Manuals: A Replication Study

Authors: B. Bergström, A. Ladd, A. Jones, L. Rosso, P. Michael

Abstract:

Attitudes toward treatment manuals serve as a meaningful predictor of general attitudes toward evidence-based practice. Despite demonstrating high effectiveness in treating many mental disorders, manualized treatments have been underutilized by practitioners. Thus, one can assess the state of the field regarding the adoption of evidence-based practices by surveying practitioner attitudes towards manualized treatments. This study is an adapted replication that assesses psychology graduate student attitudes towards manualized treatments, as a general marker for attitudes towards evidence-based practice. Training programs provide future clinicians with the foundation for critical skills in clinical practice. Research demonstrates that post-graduate continuing education has little to no effect on clinical practice; thus, graduate programs serve as the primary, and often final platform for all future practice. However, there are little empirical data identifying the attitudes and training of graduate students in utilizing manualized treatments. The empirical analysis of this study indicates an increase in positive attitudes among graduate student attitudes towards manualized treatments (within the United States), when compared to past surveys of professional psychologists. Findings from this study may inform graduate programs of barriers for students in developing positive attitudes toward manualized treatments and evidence-based practice. This study also serves as a preliminary predictor of the state-of-the field, in regards to professional psychologists attitudes towards evidence-based practice, if attitudes remain stable. This study indicates that the attitudes toward utilizing evidence-based practices, such as treatment manuals, has become more positive since year 2000.

Keywords: Evidence based treatment, Future of clinical science, Manualized treatment, Student attitudes towards evidence based treatments.

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6072 Vision Based Hand Gesture Recognition Using Generative and Discriminative Stochastic Models

Authors: Mahmoud Elmezain, Samar El-shinawy

Abstract:

Many approaches to pattern recognition are founded on probability theory, and can be broadly characterized as either generative or discriminative according to whether or not the distribution of the image features. Generative and discriminative models have very different characteristics, as well as complementary strengths and weaknesses. In this paper, we study these models to recognize the patterns of alphabet characters (A-Z) and numbers (0-9). To handle isolated pattern, generative model as Hidden Markov Model (HMM) and discriminative models like Conditional Random Field (CRF), Hidden Conditional Random Field (HCRF) and Latent-Dynamic Conditional Random Field (LDCRF) with different number of window size are applied on extracted pattern features. The gesture recognition rate is improved initially as the window size increase, but degrades as window size increase further. Experimental results show that the LDCRF is the best in terms of results than CRF, HCRF and HMM at window size equal 4. Additionally, our results show that; an overall recognition rates are 91.52%, 95.28%, 96.94% and 98.05% for CRF, HCRF, HMM and LDCRF respectively.

Keywords: Statistical Pattern Recognition, Generative Model, Discriminative Model, Human Computer Interaction.

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6071 Elliptic Divisibility Sequences over Finite Fields

Authors: Betül Gezer, Ahmet Tekcan, Osman Bizim

Abstract:

In this work, we study elliptic divisibility sequences over finite fields. Morgan Ward in [14], [15] gave arithmetic theory of elliptic divisibility sequences and formulas for elliptic divisibility sequences with rank two over finite field Fp. We study elliptic divisibility sequences with rank three, four and five over a finite field Fp, where p > 3 is a prime and give general terms of these sequences and then we determine elliptic and singular curves associated with these sequences.

Keywords: Elliptic divisibility sequences, singular elliptic divisibilitysequences, elliptic curves, singular curves.

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6070 The Effect of IT Service Quality Attributes on Supply Chain Management and Performance

Authors: Narasimhaiah Gorla, Annibal Scavarda

Abstract:

Nowadays, where most of the leading economies are service oriented and e-business is being widely used for their management, supply chain management has become one of the most studied and practiced fields. Quality has an important role on today-s business processes, so it is important to understand the impact of IT service quality on the performance of supply chains. This paper will start by analyzing the Supply Chain Operations Reference (SCOR) model and each of its five activities: Plan, Source, Make, Delivery, and Return. This article proposes a framework for analyzing Effect of IT Service Quality on Supply Chain Performance. Using the proposed framework, hypotheses are framed for the direct effect of IT service quality on Supply Chain Performance and its indirect effect through effective Supply Chain Management. The framework will be validated empirically based on the surveys of executives of various organizations and statistical analyses of the data collected.

Keywords: IT service quality, SCOR model, Supply Chain Management, Supply Chain Performance

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6069 Intelligent Assistive Methods for Diagnosis of Rheumatoid Arthritis Using Histogram Smoothing and Feature Extraction of Bone Images

Authors: SP. Chokkalingam, K. Komathy

Abstract:

Advances in the field of image processing envision a new era of evaluation techniques and application of procedures in various different fields. One such field being considered is the biomedical field for prognosis as well as diagnosis of diseases. This plethora of methods though provides a wide range of options to select from, it also proves confusion in selecting the apt process and also in finding which one is more suitable. Our objective is to use a series of techniques on bone scans, so as to detect the occurrence of rheumatoid arthritis (RA) as accurately as possible. Amongst other techniques existing in the field our proposed system tends to be more effective as it depends on new methodologies that have been proved to be better and more consistent than others. Computer aided diagnosis will provide more accurate and infallible rate of consistency that will help to improve the efficiency of the system. The image first undergoes histogram smoothing and specification, morphing operation, boundary detection by edge following algorithm and finally image subtraction to determine the presence of rheumatoid arthritis in a more efficient and effective way. Using preprocessing noises are removed from images and using segmentation, region of interest is found and Histogram smoothing is applied for a specific portion of the images. Gray level co-occurrence matrix (GLCM) features like Mean, Median, Energy, Correlation, Bone Mineral Density (BMD) and etc. After finding all the features it stores in the database. This dataset is trained with inflamed and noninflamed values and with the help of neural network all the new images are checked properly for their status and Rough set is implemented for further reduction.

Keywords: Computer Aided Diagnosis, Edge Detection, Histogram Smoothing, Rheumatoid Arthritis.

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6068 Effect of Manganese Doping on Ferrroelectric Properties of (K0.485Na0.5Li0.015)(Nb0.98V0.02)O3 Lead-Free Piezoceramic

Authors: Chongtham Jiten, Radhapiyari Laishram, K. Chandramani Singh

Abstract:

Alkaline niobate (Na0.5K0.5)NbO3 ceramic system has attracted major attention in view of its potential for replacing the highly toxic but superior lead zirconate titanate (PZT) system for piezoelectric applications. Recently, a more detailed study of this system reveals that the ferroelectric and piezoelectric properties are optimized in the Li- and V-modified system having the composition (K0.485Na0.5Li0.015)(Nb0.98V0.02)O3. In the present work, we further study the pyroelectric behaviour of this composition along with another doped with Mn4+. So, (K0.485Na0.5Li0.015)(Nb0.98V0.02)O3 + x MnO2 (x = 0, and 0.01 wt. %) ceramic compositions were synthesized by conventional ceramic processing route. X-ray diffraction study reveals that both the undoped and Mn4+-doped ceramic samples prepared crystallize into a perovskite structure having orthorhombic symmetry. Dielectric study indicates that Mn4+ doping has little effect on both the Curie temperature (Tc) and tetragonal-orthorhombic phase transition temperature (Tot). The bulk density, room-temperature dielectric constant (εRT), and room-c The room-temperature coercive field (Ec) is observed to be lower in Mn4+ doped sample. The detailed analysis of the P-E hysteresis loops over the range of temperature from about room temperature to Tot points out that enhanced ferroelectric properties exist in this temperature range with better thermal stability for the Mn4+ doped ceramic. The study reveals that small traces of Mn4+ can modify (K0.485Na0.5Li0.015)(Nb0.98V0.02)O3 system so as to improve its ferroelectric properties with good thermal stability over a wide range of temperature.

Keywords: Ceramics, dielectric properties, ferroelectric properties, lead-free, sintering, thermal stability.

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