Search results for: comparative study
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13072

Search results for: comparative study

4372 Optimal Trailing Edge Flap Positions of Helicopter Rotor for Various Thrust Coefficients to Solidity (Ct/σ) Ratios

Authors: Saijal K. K., K. Prabhakaran Nair

Abstract:

This study aims to determine change in optimal locations of dual trailing-edge flaps for various thrust coefficient to solidity (Ct /σ) ratios of helicopter to achieve minimum hub vibration levels, with low penalty in terms of required trailing-edge flap control power. Polynomial response functions are used to approximate hub vibration and flap power objective functions. Single objective and multiobjective optimization is carried with the objective of minimizing hub vibration and flap power. The optimization result shows that the inboard flap location at low Ct /σ ratio move farther from the baseline value and at high Ct /σ ratio move towards the root of the blade for minimizing hub vibration.

Keywords: Helicopter rotor, Trailing-edge flap, Thrust coefficient to solidity (Ct /σ) ratio, Optimization.

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4371 Computational Study and Wear Prediction of Steam Turbine Blade with Titanium-Nitride Coating Deposited by Physical Vapor Deposition Method

Authors: Karuna Tuchinda, Sasithon Bland

Abstract:

This work investigates the wear of a steam turbine blade coated with titanium nitride (TiN), and compares to the wear of uncoated blades. The coating is deposited on by physical vapor deposition (PVD) method. The working conditions of the blade were simulated and surface temperature and pressure values as well as flow velocity and flow direction were obtained. This data was used in the finite element wear model developed here in order to predict the wear of the blade. The wear mechanisms considered are erosive wear due to particle impingement and fluid jet, and fatigue wear due to repeated impingement of particles and fluid jet. Results show that the life of the TiN-coated blade is approximately 1.76 times longer than the life of the uncoated one.

Keywords: Physical vapour deposition, steam turbine blade, titanium-based coating, wear prediction.

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4370 Multi-Line Power Flow Control using Interline Power Flow Controller (IPFC) in Power Transmission Systems

Authors: A.V.Naresh Babu, S.Sivanagaraju, Ch.Padmanabharaju, T.Ramana

Abstract:

The interline power flow controller (IPFC) is one of the latest generation flexible AC transmission systems (FACTS) controller used to control power flows of multiple transmission lines. This paper presents a mathematical model of IPFC, termed as power injection model (PIM). This model is incorporated in Newton- Raphson (NR) power flow algorithm to study the power flow control in transmission lines in which IPFC is placed. A program in MATLAB has been written in order to extend conventional NR algorithm based on this model. Numerical results are carried out on a standard 2 machine 5 bus system. The results without and with IPFC are compared in terms of voltages, active and reactive power flows to demonstrate the performance of the IPFC model.

Keywords: flexible AC transmission systems (FACTS), interline power flow controller (IPFC), power injection model (PIM), power flow control.

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4369 Analysis of Cooperative Learning Behavior Based on the Data of Students' Movement

Authors: Wang Lin, Li Zhiqiang

Abstract:

The purpose of this paper is to analyze the cooperative learning behavior pattern based on the data of students' movement. The study firstly reviewed the cooperative learning theory and its research status, and briefly introduced the k-means clustering algorithm. Then, it used clustering algorithm and mathematical statistics theory to analyze the activity rhythm of individual student and groups in different functional areas, according to the movement data provided by 10 first-year graduate students. It also focused on the analysis of students' behavior in the learning area and explored the law of cooperative learning behavior. The research result showed that the cooperative learning behavior analysis method based on movement data proposed in this paper is feasible. From the results of data analysis, the characteristics of behavior of students and their cooperative learning behavior patterns could be found.

Keywords: Behavior pattern, cooperative learning, data analyze, K-means clustering algorithm.

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4368 Evaluation of Corrosion Property of Aluminium-Zirconium Dioxide (AlZrO2) Nanocomposites

Authors: M. Ramachandra, G. Dilip Maruthi, R. Rashmi

Abstract:

This paper aims to study the corrosion property of aluminum matrix nanocomposite of an aluminum alloy (Al-6061) reinforced with zirconium dioxide (ZrO2) particles. The zirconium dioxide particles are synthesized by solution combustion method. The nanocomposite materials are prepared by mechanical stir casting method, varying the percentage of n-ZrO2 (2.5%, 5% and 7.5% by weight). The corrosion behavior of base metal (Al-6061) and Al/ZrO2 nanocomposite in seawater (3.5% NaCl solution) is measured using the potential control method. The corrosion rate is evaluated by Tafel extrapolation technique. The corrosion potential increases with the increase in wt.% of n-ZrO2 in the nanocomposite which means the decrease in corrosion rate. It is found that on addition of n-ZrO2 particles to the aluminum matrix, the corrosion rate has decreased compared to the base metal.

Keywords: Al6061 alloy, corrosion, solution combustion, stir casting, Potentiostat, Zirconium Dioxide.

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4367 Paradigm of Digital Twin Application in Project Management in Architecture, Engineering and Construction

Authors: Kwok Tak Kit

Abstract:

With the growing trend of adoption of advanced technologies like, building information modeling, artificial intelligence, wireless network, the collaboration and integration of these technologies into digital twin become more prominent in architecture, engineering and construction (AEC) industry in view of the nature and scale of AEC industry which efficiently adopted the digital twin. Digital twin is provided to be effective for AEC professions for design and project management. The digital concept is continuously developing and it is vital for AEC professionals and other stakeholders to understand the digital twin concept and the adoption of various advanced building technologies related to the AEC industry. This paper is to review the application of digital twins application in project management in AEC industry and highlight the challenge of AEC partitioners faced by the revolution of technologies including digital twins and building information modelling (BIM) for further research and future study.

Keywords: Digital Twin, AEC, building information modeling, project management, internet of things.

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4366 GA Based Optimal Feature Extraction Method for Functional Data Classification

Authors: Jun Wan, Zehua Chen, Yingwu Chen, Zhidong Bai

Abstract:

Classification is an interesting problem in functional data analysis (FDA), because many science and application problems end up with classification problems, such as recognition, prediction, control, decision making, management, etc. As the high dimension and high correlation in functional data (FD), it is a key problem to extract features from FD whereas keeping its global characters, which relates to the classification efficiency and precision to heavens. In this paper, a novel automatic method which combined Genetic Algorithm (GA) and classification algorithm to extract classification features is proposed. In this method, the optimal features and classification model are approached via evolutional study step by step. It is proved by theory analysis and experiment test that this method has advantages in improving classification efficiency, precision and robustness whereas using less features and the dimension of extracted classification features can be controlled.

Keywords: Classification, functional data, feature extraction, genetic algorithm, wavelet.

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4365 Revolving Ferrofluid Flow in Porous Medium with Rotating Disk

Authors: Paras Ram, Vikas Kumar

Abstract:

An attempt has been made to study the effect of rotation on incompressible, electrically non-conducting ferrofluid in porous medium on Axi-symmetric steady flow over a rotating disk excluding thermal effects. Here, we solved the boundary layer equations with boundary conditions using Neuringer-Rosensweig model considering the z-axis as the axis of rotation. The non linear boundary layer equations involved in the problem are transformed to the non linear coupled ordinary differential equations by Karman's transformation and solved by power series approximations. Besides numerically calculating the velocity components and pressure for different values of porosity parameter with the variation of Karman's parameter we have also calculated the displacement thickness of boundary layer, the total volume flowing outward the z-axis and angle between wall and ferrofluid. The results for all above variables are obtained numerically and discussed graphically.

Keywords: Ferrofluid, magnetic field porous medium, rotating disk.

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4364 Mamdani Model based Adaptive Neural Fuzzy Inference System and its Application

Authors: Yuanyuan Chai, Limin Jia, Zundong Zhang

Abstract:

Hybrid algorithm is the hot issue in Computational Intelligence (CI) study. From in-depth discussion on Simulation Mechanism Based (SMB) classification method and composite patterns, this paper presents the Mamdani model based Adaptive Neural Fuzzy Inference System (M-ANFIS) and weight updating formula in consideration with qualitative representation of inference consequent parts in fuzzy neural networks. M-ANFIS model adopts Mamdani fuzzy inference system which has advantages in consequent part. Experiment results of applying M-ANFIS to evaluate traffic Level of service show that M-ANFIS, as a new hybrid algorithm in computational intelligence, has great advantages in non-linear modeling, membership functions in consequent parts, scale of training data and amount of adjusted parameters.

Keywords: Fuzzy neural networks, Mamdani fuzzy inference, M-ANFIS

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4363 An Experimental Study of a Self-Supervised Classifier Ensemble

Authors: Neamat El Gayar

Abstract:

Learning using labeled and unlabelled data has received considerable amount of attention in the machine learning community due its potential in reducing the need for expensive labeled data. In this work we present a new method for combining labeled and unlabeled data based on classifier ensembles. The model we propose assumes each classifier in the ensemble observes the input using different set of features. Classifiers are initially trained using some labeled samples. The trained classifiers learn further through labeling the unknown patterns using a teaching signals that is generated using the decision of the classifier ensemble, i.e. the classifiers self-supervise each other. Experiments on a set of object images are presented. Our experiments investigate different classifier models, different fusing techniques, different training sizes and different input features. Experimental results reveal that the proposed self-supervised ensemble learning approach reduces classification error over the single classifier and the traditional ensemble classifier approachs.

Keywords: Multiple Classifier Systems, classifier ensembles, learning using labeled and unlabelled data, K-nearest neighbor classifier, Bayes classifier.

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4362 Blood Elements Activation in Hemodialysis – Animal Model Studies

Authors: Karolina Grzeszczuk-Kuć, Jolanta Bujok, Tomasz Walski, Małgorzata Komorowska

Abstract:

Haemodialysis (HD) is a procedure saving patient lives around the world, unfortunately it brings numerous complications. Oxidative stress is one of the major factors which lead to erythrocytes destruction during extracorporeal circulation. Repeated HD procedures destroy blood elements and the organism is not able to keep up with their production. 30 HD procedures on healthy sheep were performed to evaluate effects of such treatment. Oxidative stress study was performed together with an analysis of basic blood parameters and empirical assessment of dialyzer condition after the procedure. A reversible decline in absolute leukocyte count, during first 30 min of HD, was observed. Blood clots were formed in the area of the blood inlet and outlet of the dialyzer. Our results are consistent with outcomes presented throughout the literature specifically with respect to the effects observed in humans and will provide a basis to evaluate methods for blood protection during haemodialysis.

Keywords: Animal model, blood components, haemodialysis, leukocytes, oxidative stress, sheep.

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4361 A Model-Driven Approach of User Interface for MVP Rich Internet Application

Authors: Sarra Roubi, Mohammed Erramdani, Samir Mbarki

Abstract:

This paper presents an approach for the model-driven generating of Rich Internet Application (RIA) focusing on the graphical aspect. We used well known Model-Driven Engineering (MDE) frameworks and technologies, such as Eclipse Modeling Framework (EMF), Graphical Modeling Framework (GMF), Query View Transformation (QVTo) and Acceleo to enable the design and the code automatic generation of the RIA. During the development of the approach, we focused on the graphical aspect of the application in terms of interfaces while opting for the Model View Presenter pattern that is designed for graphics interfaces. The paper describes the process followed to define the approach, the supporting tool and presents the results from a case study.

Keywords: Code generation, Design Pattern, metamodel, Model Driven Engineering, MVP, Rich Internet Application, transformation, User Interface.

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4360 Server Virtualization Using User Behavior Model Focus on Provisioning Concept

Authors: D. Prangchumpol

Abstract:

Server provisioning is one of the most attractive topics in virtualization systems. Virtualization is a method of running multiple independent virtual operating systems on a single physical computer. It is a way of maximizing physical resources to maximize the investment in hardware. Additionally, it can help to consolidate servers, improve hardware utilization and reduce the consumption of power and physical space in the data center. However, management of heterogeneous workloads, especially for resource utilization of the server, or so called provisioning becomes a challenge. In this paper, a new concept for managing workloads based on user behavior is presented. The experimental results show that user behaviors are different in each type of service workload and time. Understanding user behaviors may improve the efficiency of management in provisioning concept. This preliminary study may be an approach to improve management of data centers running heterogeneous workloads for provisioning in virtualization system.

Keywords: association rule, provisioning, server virtualization.

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4359 Optimal Design of Reference Node Placement for Wireless Indoor Positioning Systems in Multi-Floor Building

Authors: Kittipob Kondee, Chutima Prommak

Abstract:

In this paper, we propose an optimization technique that can be used to optimize the placements of reference nodes and improve the location determination performance for the multi-floor building. The proposed technique is based on Simulated Annealing algorithm (SA) and is called MSMR-M. The performance study in this work is based on simulation. We compare other node-placement techniques found in the literature with the optimal node-placement solutions obtained from our optimization. The results show that using the optimal node-placement obtained by our proposed technique can improve the positioning error distances up to 20% better than those of the other techniques. The proposed technique can provide an average error distance within 1.42 meters.

Keywords: Indoor positioning System, Optimization System design, Multi-Floor Building, Wireless Sensor Networks.

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4358 Towards a Security Model against Denial of Service Attacks for SIP Traffic

Authors: Arellano Karina, Diego Avila-Pesántez, Leticia Vaca-Cárdenas, Alberto Arellano, Carmen Mantilla

Abstract:

Nowadays, security threats in Voice over IP (VoIP) systems are an essential and latent concern for people in charge of security in a corporate network, because, every day, new Denial-of-Service (DoS) attacks are developed. These affect the business continuity of an organization, regarding confidentiality, availability, and integrity of services, causing frequent losses of both information and money. The purpose of this study is to establish the necessary measures to mitigate DoS threats, which affect the availability of VoIP systems, based on the Session Initiation Protocol (SIP). A Security Model called MS-DoS-SIP is proposed, which is based on two approaches. The first one analyzes the recommendations of international security standards. The second approach takes into account weaknesses and threats. The implementation of this model in a VoIP simulated system allowed to minimize the present vulnerabilities in 92% and increase the availability time of the VoIP service into an organization.

Keywords: Denial-of-service SIP attacks, MS-DoS-SIP, security model, VoIP-SIP vulnerabilities.

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4357 In vivo Histomorphometric and Corrosion Analysis of Ti-Ni-Cr Shape Memory Alloys in Rabbits

Authors: T. Ahmed, Z. Butt, M. Ali, S. Attiq, M. Ali

Abstract:

A series of Ti based shape memory alloys with composition of Ti50Ni49Cr1, Ti50Ni47Cr3 and Ti50Ni45Cr5 were developed by vacuum arc-melting under a purified argon atmosphere. The histometric and corrosion evaluation of Ti-Ni-Cr shape memory alloys have been considered in this research work. The alloys were developed by vacuum arc melting and implanted subcutaneously in rabbits for 4, 8 and 12 weeks. Metallic implants were embedded in order to determine the outcome of implantation on histometric and corrosion evaluation of Ti-Ni-Cr metallic strips. Encapsulating membrane formation around the alloys was minimal in the case of all materials. After histomorphometric analyses it was possible to demonstrate that there were no statistically significant differences between the materials. Corrosion rate was also determined in this study which is within acceptable range. The results showed the Ti- Ni-Cr alloy was neither cytotoxic, nor have any systemic reaction on living system in any of the test performed. Implantation shows good compatibility and a potential of being used directly in vivo system.

Keywords: Shape memory alloy, Ti-Ni-Fe, histomorphometric, corrosion.

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4356 Functional Decomposition Based Effort Estimation Model for Software-Intensive Systems

Authors: Nermin Sökmen

Abstract:

An effort estimation model is needed for softwareintensive projects that consist of hardware, embedded software or some combination of the two, as well as high level software solutions. This paper first focuses on functional decomposition techniques to measure functional complexity of a computer system and investigates its impact on system development effort. Later, it examines effects of technical difficulty and design team capability factors in order to construct the best effort estimation model. With using traditional regression analysis technique, the study develops a system development effort estimation model which takes functional complexity, technical difficulty and design team capability factors as input parameters. Finally, the assumptions of the model are tested.

Keywords: Functional complexity, functional decomposition, development effort, technical difficulty, design team capability, regression analysis.

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4355 Effects of Maternal Nutrition at Different Stages of Pregnancy in Bali Cows on Growth Performance of the Offspring to Weaning

Authors: D. P. Rahardja, A. L. Toleng, M. Yusuf

Abstract:

The objective of this study was to investigate the lifelong effect of in utero nutrition fed at different stages of pregnancy in Bali cows (n = 40): (U1) without in utero nutrition (0 – parturition, negative control); (U2) 0 – 90 d of gestation; (U3) 90 - 180 d of gestation; (U4) 180 d – parturition; and (U5) in utero nutrition along gestation period (0 d to parturition – positive control) on the growth performance of the offspring to weaning age. The results indicated that effect of maternal nutrition on male and female offspring were particularly indicated by the growth performance of both the male and female offspring from birth to weaning.

Keywords: Bali cows, birth weight, maternal nutrition, preweaning daily gain, weaning weight.

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4354 A Numerical Simulation of Solar Distillation for Installation in Chabahar-Iran

Authors: Masoud Afrand, Amin Behzadmehr, Arash Karimipour

Abstract:

The world demand for potable water is increasing every day with growing population. Desalination using solar energy is suitable for potable water production from brackish and seawater. In this paper, we present a theoretical study of solar distillation in a single basin under the open environmental conditions of Chabahar-Iran. The still has a base area of 2000mm×500mm with a glass cover inclined at 25° in order to obtain extra solar energy. We model the still and conduct its energy balance equations under minor assumptions. We computed the temperatures of glass cover, seawater interface, moist air and bottom using numerical method. The investigation addressed the following: The still productivity, distilled water salinity and still performance in terms of the still efficiency. Calculated still productivity in July was higher than December. So in this paper, we show that still productivity is directly functioning of solar radiation.

Keywords: Inclined Solar still, Solar energy, Solar desalination, Numerical Simulation.

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4353 Development of the Structure of the Knowledgebase for Countermeasures in the Knowledge Acquisition Process for Trouble Prediction in Healthcare Processes

Authors: Shogo Kato, Daisuke Okamoto, Satoko Tsuru, Yoshinori Iizuka, Ryoko Shimono

Abstract:

Healthcare safety has been perceived important. It is essential to prevent troubles in healthcare processes for healthcare safety. Trouble prevention is based on trouble prediction using accumulated knowledge on processes, troubles, and countermeasures. However, information on troubles has not been accumulated in hospitals in the appropriate structure, and it has not been utilized effectively to prevent troubles. In the previous study, however a detailed knowledge acquisition process for trouble prediction was proposed, the knowledgebase for countermeasures was not involved. In this paper, we aim to propose the structure of the knowledgebase for countermeasures, in the knowledge acquisition process for trouble prediction in healthcare process. We first design the structure of countermeasures and propose the knowledge representation form on countermeasures. Then, we evaluate the validity of the proposal, by applying it into an actual hospital.

Keywords: Trouble prevention, knowledge structure, structured knowledge, reusable knowledge.

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4352 Verification of the Simultaneous Local Extraction Method of Base and Thermal Resistance of Bipolar Transistors

Authors: Robert Setekera, Luuk Tiemeijer, Ramses van der Toorn

Abstract:

In this paper an extensive verification of the extraction method (published earlier) that consistently accounts for self-heating and Early effect to accurately extract both base and thermal resistance of bipolar junction transistors is presented. The method verification is demonstrated on advanced RF SiGe HBTs were the extracted results for the thermal resistance are compared with those from another published method that ignores the effect of Early effect on internal base-emitter voltage and the extracted results of the base resistance are compared with those determined from noise measurements. A self-consistency of our method in the extracted base resistance and thermal resistance using compact model simulation results is also carried out in order to study the level of accuracy of the method.

Keywords: Avalanche, Base resistance, Bipolar transistor, Compact modeling, Early voltage, Thermal resistance, Self-heating, parameter extraction.

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4351 Exploring the Professional Competency Contents for International Marketer in Taiwan

Authors: Shu-Ning Liou

Abstract:

The main purpose of this study was to establish Professional Competency Contents for International Marketer in Taiwan. To establish these contents a set of interviews with international marketing managers and three rounds of Delphi Technique surveys were employed. Five international marketing managers were interviewed for discussions on definitions, framework, and items of international marketing competency. A questionnaire for the " Delphi Technique Survey " was developed based on the results acquired from the interviews. The resulting questionnaire was distributed to another group of 30 international marketer of trading companies in Taiwan. After three rounds of Delphi Technique Survey with these participants, the "Contents of Professional Competency for International Marketer " was established. Five dimensions and thirty indicators were identified. It is hoped that the proposed contents could be served as a self-evaluation tool for international marketer as well as the basis for staffing and training programs for international marketer in Taiwan.

Keywords: Professional competency, International marketer, Delphi technique

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4350 Aflatoxins Aggravate the Incidence of Salmonellosis Outbreak in Fattening Calves: A Case Study

Authors: Abdel-Rahman A., El Okle O. S.

Abstract:

Fever, bloody diarrhea and high mortality rate were the main clinical finding in a group of fattening calves. Analysis of corn silage revealed presence of aflatoxins at level of 370 ppb. This level of aflatoxins in the feed of cattle is somewhat low to be the main cause of reported signs. Leukocytopenia, anemia, decreased lymphocytic activity and lowered phagocytic index are the main hematological and immunological alterations in diseased calves. Bacteriological investigation revealed isolation of pathogenic Salmonella typhimurium from the rectal swabs of diseased calves. Our results suggested that, long duration of exposure to aflatoxins even at small concentrations may considered as predisposing factor for the incidence of natural infectious outbreaks as salmonellosis due to its immunosuppressive effect. We can conclude that the veterinarians and owners must be given an attention to the relation between aflatoxicosis and salmonellosis under field condition. We are recommended that the treatment program during similar outbreaks must be including anti-aflatoxins preparations beside the antimicrobial therapy.

Keywords: Aflatoxins, Calves, Salmonellosis.

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4349 Yang-Lee Edge Singularity of the Infinite-Range Ising Model

Authors: Seung-Yeon Kim

Abstract:

The Ising ferromagnet, consisting of magnetic spins, is the simplest system showing phase transitions and critical phenomena at finite temperatures. The Ising ferromagnet has played a central role in our understanding of phase transitions and critical phenomena. Also, the Ising ferromagnet explains the gas-liquid phase transitions accurately. In particular, the Ising ferromagnet in a nonzero magnetic field has been one of the most intriguing and outstanding unsolved problems. We study analytically the partition function zeros in the complex magnetic-field plane and the Yang-Lee edge singularity of the infinite-range Ising ferromagnet in an external magnetic field. In addition, we compare the Yang-Lee edge singularity of the infinite-range Ising ferromagnet with that of the square-lattice Ising ferromagnet in an external magnetic field.

Keywords: Ising ferromagnet, Magnetic field, Partition function zeros, Yang-Lee edge singularity.

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4348 Analysis of Suitability of Online Assessment by Maintaining Critical Thinking

Authors: Mohamed Chabi, Mohammad Shahid Jamil, Mahmoud I Syam

Abstract:

The purpose of this study is to determine whether paper assessment especially in the subject mathematics will ever be completely replaced by online assessment using Learning Management System and Content Management System such as blackboard. Testing students has moved from the traditional scribbling and sketching on paper towards working online on a screen and keyboard. It is found that online assessment by using selective types of questions like multiple choices, true or false and final answer questions don’t reflect the actual understanding of students in solving the problems and teachers can’t determine the weakness points of students. In addition, it is showed that OBMCQs are a very good tool for self-assessment and when teachers are testing for knowledge and facts. But when it comes to the skills, OBMCQs are poor tools for measuring the ability to apply knowledge to complex math problem. 

Keywords: Paper assessment, online assessment, learning management system, content management system.

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4347 Investigation of Dissolution in Diammonium Hydrogen Phosphate Solutions of Gypsum

Authors: Turan Çalban, Nursel Keskin, Sabri Çolak, Soner Kuşlu

Abstract:

Gypsum (CaSO4.2H2O) is a mineral that is found in large quantities in the Turkey and in the World. In this study, the dissolution of this mineral in the diammonium hydrogen phosphate solutions has been studied. The dissolution and dissolution kinetics of gypsum in diammonium hydrogen phosphate solutions will be useful for evaluating of solid wastes containing gypsum. Parameters such as diammonium hydrogen phosphate concentration, temperature and stirring speed affecting on the dissolution rate of the gypsum in diammonium hydrogen phosphate solutions were investigated. In experimental studies have researched effectiveness of the selected parameters. The dissolution of gypsum were examined in two parts at low and high temperatures. The experimental results were successfully correlated by linear regression using Statistica program. Dissolution curves were evaluated shrinking core models for solidfluid systems. The activation energy was found to be 34.58 kJ/mol and 44.45 kJ/mol for the low and the high temperatures. The dissolution of gypsum was controlled by chemical reaction both low temperatures and high temperatures.

Keywords: Diammonium hydrogen phosphate, Dissolution, Gypsum, Kinetics.

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4346 Enhancing Thermal Efficiency of Double Skin Façade Buildings in Semi-Arid Climate

Authors: Farid Vahedi

Abstract:

There is a great deal of interest in constructing Double Skin Facade (DSF) structures which are considered as modern movement in field of Energy Conservation, renewable energies, and Architecture design. This trend provides many conclusive alternatives which are frequently associated with sustainable building. In this paper a building with Double Skin Facade is considered in the semiarid climate of Tehran, Iran, in order to consider the DSF-s performance during hot seasons. Mathematical formulations calculate solar heat gain by the external skin. Moreover, Computational Fluid Dynamics (CFD) simulations were performed on the case study building to enhance effectiveness of the facade. The conclusion divulged difference of gained energy by the cavity and room with and without blind and louvers. Some solutions were introduced to surge the performance of natural ventilation by plunging the cooling loads in summer.

Keywords: Double Skin Façade Buildings, Energy Conservation, Renewable Energy, Natural Ventilation, Semi-arid Climate.

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4345 Applying Lean Principles, Tools and Techniques in Set Parts Supply Implementation

Authors: Suhartini M. Jainury, Rizauddin Ramli, Mohd Nizam A. Rahman

Abstract:

Lean, which was initially developed by Toyota, is widely implemented in other companies to improve competitiveness. This research is an attempt to identify the adoption of lean in the production system of Malaysian car manufacturer, Proton using case study approach. To gain the in-depth information regarding lean implementation, an activity on the assembly line called Set Parts Supply (SPS) was studied. The result indicates that by using lean principles, tools and techniques in the implementation of SPS enabled to achieve the goals on safety, quality, cost, delivery and morale. The implementation increased the size of the workspace, improved the quality of assembly and the delivery of parts supply, reduced the manpower, achieved cost savings on electricity and also increased the motivation of manpower in respect of attendance at work. A framework of SPS implementation is suggested as a contribution for lean practices in production system.

Keywords: Assembly line, lean manufacturing, production, parts supply.

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4344 Evaluation of Neighbourhood Characteristics and Active Transport Mode Choice

Authors: Tayebeh Saghapour, Sara Moridpour, Russell George Thompson

Abstract:

One of the common aims of transport policy makers is to switch people’s travel to active transport. For this purpose, a variety of transport goals and investments should be programmed to increase the propensity towards active transport mode choice. This paper aims to investigate whether built environment features in neighbourhoods could enhance the odds of active transportation. The present study introduces an index measuring public transport accessibility (PTAI), and a walkability index along with socioeconomic variables to investigate mode choice behaviour. Using travel behaviour data, an ordered logit regression model is applied to examine the impacts of explanatory variables on walking trips. The findings indicated that high rates of active travel are consistently associated with higher levels of walking and public transport accessibility.

Keywords: Active transport, public transport accessibility, walkability, ordered logit model.

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4343 An Exact Solution of Axi-symmetric Conductive Heat Transfer in Cylindrical Composite Laminate under the General Boundary Condition

Authors: M.kayhani, M.Nourouzi, A. Amiri Delooei

Abstract:

This study presents an exact general solution for steady-state conductive heat transfer in cylindrical composite laminates. Appropriate Fourier transformation has been obtained using Sturm-Liouville theorem. Series coefficients are achieved by solving a set of equations that related to thermal boundary conditions at inner and outer of the cylinder, also related to temperature continuity and heat flux continuity between each layer. The solution of this set of equations are obtained using Thomas algorithm. In this paper, the effect of fibers- angle on temperature distribution of composite laminate is investigated under general boundary conditions. Here, we show that the temperature distribution for any composite laminates is between temperature distribution for laminates with θ = 0° and θ = 90° .

Keywords: exact solution, composite laminate, heat conduction, cylinder, Fourier transformation.

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