Search results for: ITAE criterion
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 346

Search results for: ITAE criterion

106 A P2P File Sharing Technique by Indexed-Priority Metric

Authors: Toshinori Takabatake, Yoshikazu Komano

Abstract:

Recently, the improvements in processing performance of a computer and in high speed communication of an optical fiber have been achieved, so that the amount of data which are processed by a computer and flowed on a network has been increasing greatly. However, in a client-server system, since the server receives and processes the amount of data from the clients through the network, a load on the server is increasing. Thus, there are needed to introduce a server with high processing ability and to have a line with high bandwidth. In this paper, concerning to P2P networks to resolve the load on a specific server, a criterion called an Indexed-Priority Metric is proposed and its performance is evaluated. The proposed metric is to allocate some files to each node. As a result, the load on a specific server can distribute them to each node equally well. A P2P file sharing system using the proposed metric is implemented. Simulation results show that the proposed metric can make it distribute files on the specific server.

Keywords: peer-to-peer, file-sharing system, load-balancing, dependability

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105 Passenger Seat Vibration Comparison Using ANFIS Control in Active Quarter Car Model

Authors: Devdutt

Abstract:

In this paper, vibration control response of passenger seat in quarter car model having three degrees of freedom is studied. Three different control strategies are taken into account using Adaptive Neuro Fuzzy Inference System (ANFIS) controller. In first case, ANFIS controller is applied in main suspension of active quarter car model. In second case, passenger seat suspension is assembled with ANFIS controller. Finally, both main and passenger seat suspensions are integrated with ANFIS controller. Simulation work under random road excitations is performed using passive and controlled quarter car models for performance comparison of passenger ride comfort. Ride comfort analysis is also compared as per ISO 2631-1 criterion. The obtained simulation responses are compared taking passenger seat acceleration and displacement response in time and frequency domain for the selection of best control strategy in designed quarter car model.

Keywords: Active suspension system, ANFIS controller, passenger ride comfort, quarter car model.

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104 Determining Factors for ISO14001 EMS Implementation among SMEs in Malaysia: A Resource Based View

Authors: Goh Yen Nee

Abstract:

This research aimed to find out the determining factors for ISO 14001 EMS implementation among SMEs in Malaysia from the Resource based view. A cross-sectional approach using survey was conducted. A research model been proposed which comprises of ISO 14001 EMS implementation as the criterion variable while physical capital resources (i.e. environmental performance tracking and organizational infrastructures), human capital resources (i.e. top management commitment and support, training and education, employee empowerment and teamwork) and organizational capital resources (i.e. recognition and reward, organizational culture and organizational communication) as the explanatory variables. The research findings show that only environmental performance tracking, top management commitment and support and organizational culture are found to be positively and significantly associated with ISO 14001 EMS implementation. It is expected that this research will shed new knowledge and provide a base for future studies about the role played by firm-s internal resources.

Keywords: ISO 14001 Environmental Management System, Malaysia, Resource based view, SMEs

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103 Optimum Design of Pressure Vessel Subjected to Autofrettage Process

Authors: Abu Rayhan Md. Ali, Nidul Ch. Ghosh, Tanvir-E-Alam

Abstract:

The effect of autofrettage process in strain hardened thick-walled pressure vessels has been investigated theoretically by finite element modeling. Equivalent von Mises stress is used as yield criterion to evaluate the optimum autofrettage pressure and the optimum radius of elastic-plastic junction. It has been observed that the optimum autofrettage pressure increases along with the working pressure. For two different working pressures, the effect of the ratio of outer to inner radius (b/a=k) value on the optimum autofrettage pressure is also noticed. The Optimum autofrettage pressure solely depends on K value rather than on the inner or outer radius. Furthermore, percentage reduction of von Mises stresses is compared for different working pressures and different k values. Maximum von Mises stress developed at different autofrettage pressure is equated for elastic perfectly plastic and elastic-plastic material with different slope of strain hardening segment. Cylinder material having higher slope of strain hardening segment provides better benedictions in the autofrettage process.

Keywords: Autofrettage, elastic plastic junction, pressure vessel, von Mises stress.

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102 The Modification of the Mixed Flow Pump with Respect to Stability of the Head Curve

Authors: Roman Klas, František Pochylý, Pavel Rudolf

Abstract:

This paper is focused on the CFD simulation of the radiaxial pump (i.e. mixed flow pump) with the aim to detect the reasons of Y-Q characteristic instability. The main reasons of pressure pulsations were detected by means of the analysis of velocity and pressure fields within the pump combined with the theoretical approach. Consequently, the modifications of spiral case and pump suction area were made based on the knowledge of flow conditions and the shape of dissipation function. The primary design of pump geometry was created as the base model serving for the comparison of individual modification influences. The basic experimental data are available for this geometry. This approach replaced the more complicated and with respect to convergence of all computational tasks more difficult calculation for the compressible liquid flow. The modification of primary pump consisted in inserting the three fins types. Subsequently, the evaluation of pressure pulsations, specific energy curves and visualization of velocity fields were chosen as the criterion for successful design. 

Keywords: CFD, radiaxial pump, spiral case, stability

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101 Effect of Linear Thermal Gradient on Steady-State Creep Behavior of Isotropic Rotating Disc

Authors: Minto Rattan, Tania Bose, Neeraj Chamoli

Abstract:

The present paper investigates the effect of linear thermal gradient on the steady-state creep behavior of rotating isotropic disc using threshold stress based Sherby’s creep law. The composite discs made of aluminum matrix reinforced with silicon carbide particulate has been taken for analysis. The stress and strain rate distributions have been calculated for discs rotating at linear thermal gradation using von Mises’ yield criterion. The material parameters have been estimated by regression fit of the available experimental data. The results are displayed and compared graphically in designer friendly format for the above said temperature profile with the disc operating under uniform temperature profile. It is observed that radial and tangential stresses show minor variation and the strain rates vary significantly in the presence of thermal gradation as compared to disc having uniform temperature.

Keywords: Creep, isotropic, steady-state, thermal gradient.

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100 Toward Integrative Stormwater Design in Urban Spaces

Authors: Bruce K. Ferguson

Abstract:

The design requirements for successful human accommodation in urban spaces are well known; and the range of facilities available for meeting urban water quality and quantity requirements is also well established. Their competing requirements must be reconciled in order for urban spaces to be successful for both. This paper outlines the separate human and water imperatives and their interactions in urban spaces. Stormwater management facilities- relative potential contributions to urban spaces are contrasted, and design choices for achieving those potentials are described. This study uses human success of urban space as the evaluative criterion of stormwater amenity: human values call on stormwater facilities to contribute to successful human spaces. Placing water-s contribution under the overall idea of successful urban space is an evolution from previous subjective evaluations. The information is based on photographs and notes from approximately 1,000 stormwater facilities and urban sites collected during the last 35 years in North America and overseas, and the author-s experience on multi-disciplinary design teams. This conceptual study combines the disciplinary roles of engineering, landscape architecture, and sociology in effecting successful urban design.

Keywords: Stormwater, SUDS, Urban design, Values, Urban space.

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99 An Optimization Analysis on an Automotive Component with Fatigue Constraint Using HyperWorks Software for Environmental Sustainability

Authors: W. M. Wan Muhamad, E. Sujatmika, M.R. Idris, S.A. Syed Ahmad

Abstract:

A finite element analysis (FEA) computer software HyperWorks is utilized in re-designing an automotive component to reduce its mass. Reduction of components mass contributes towards environmental sustainability by saving world-s valuable metal resources and by reducing carbon emission through improved overall vehicle fuel efficiency. A shape optimization analysis was performed on a rear spindle component. Pre-processing and solving procedures were performed using HyperMesh and RADIOSS respectively. Shape variables were defined using HyperMorph. Then optimization solver OptiStruct was utilized with fatigue life set as a design constraint. Since Stress-Number of Cycle (S-N) theory deals with uni-axial stress, the Signed von Misses stress on the component was used for looking up damage on S-N curve, and Gerber criterion for mean stress corrections. The optimization analysis resulted in mass reduction of 24% of the original mass. The study proved that the adopted approach has high potential use for environmental sustainability.

Keywords: Environmental Sustainability, Shape Optimization, Fatigue, Rear Spindle.

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98 Factors for Success in Eco-Industrial Town Development in Thailand

Authors: Jirarat Teeravaraprug, Tarathorn Podcharathitikull

Abstract:

Nowadays, Ministry of Industry has given an attention to develop Eco-industrial towns in Thailand. Eco-industrial towns are a way of demonstrating the application of industrial ecology and are subjects of increased interest as government, business and society. This concept of Eco-industrial town is quite new in Thailand. It is used as a way of achieving more sustainable industrial development. However, many firms or organizations have misunderstood the concept and treated with suspicion. The planning and development of Eco-industrial towns is a significant challenge for the developers and public agencies. This research then gives an attempt to determine current problems of being Eco-Industrial towns and determine success factors for developing Eco-Industrial towns in Thailand. The research starts with giving knowledge about Eco-industrial towns to stakeholders and conducting public hearing in order to acquire the problems of being Eco-industrial towns. Then, factors effecting the development of Eco-Industrial town are collected. The obtained factors are analyzed by using the concept of IOC. Then, the remained factors are categorized and structured based on the concept of AHP. A questionnaire is constructed and distributed to the experts who are involved in the Eco-industrial town project. The result shows that the most significant success criterion is management teams of industrial parks or groups and the second most significant goes to governmental policies.

Keywords: AHP, Eco-industrial town, success factors, Thailand.

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97 Performance Degradation for the GLR Test-Statistics for Spatial Signal Detection

Authors: Olesya Bolkhovskaya, Alexander Maltsev

Abstract:

Antenna arrays are widely used in modern radio systems in sonar and communications. The solving of the detection problems of a useful signal on the background of noise is based on the GLRT method. There is a large number of problem which depends on the known a priori information. In this work, in contrast to the majority of already solved problems, it is used only difference  spatial properties of the signal and noise for detection. We are analyzing the influence of the degree of non-coherence of signal and noise unhomogeneity on the performance characteristics of different GLRT statistics. The description of the signal and noise is carried out by means of the spatial covariance matrices C in the cases of different number of known information. The partially coherent signalis is simulated as a plane wave with a random angle of incidence of the wave concerning a normal. Background noise is simulated as random process with uniform distribution function in each element. The results of investigation of degradation of performance characteristics for different cases are represented in this work.

Keywords: GLRT, Neumann-Pearson’s criterion, test-statistics, degradation, spatial processing, multielement antenna array

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96 Evolved Bat Algorithm Based Adaptive Fuzzy Sliding Mode Control with LMI Criterion

Authors: P.-W. Tsai, C.-Y. Chen, C.-W. Chen

Abstract:

In this paper, the stability analysis of a GA-Based adaptive fuzzy sliding model controller for a nonlinear system is discussed. First, a nonlinear plant is well-approximated and described with a reference model and a fuzzy model, both involving FLC rules. Then, FLC rules and the consequent parameter are decided on via an Evolved Bat Algorithm (EBA). After this, we guarantee a new tracking performance inequality for the control system. The tracking problem is characterized to solve an eigenvalue problem (EVP). Next, an adaptive fuzzy sliding model controller (AFSMC) is proposed to stabilize the system so as to achieve good control performance. Lyapunov’s direct method can be used to ensure the stability of the nonlinear system. It is shown that the stability analysis can reduce nonlinear systems into a linear matrix inequality (LMI) problem. Finally, a numerical simulation is provided to demonstrate the control methodology.

Keywords: Adaptive fuzzy sliding mode control, Lyapunov direct method, swarm intelligence, evolved bat algorithm.

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95 Motor Imaginary Signal Classification Using Adaptive Recursive Bandpass Filter and Adaptive Autoregressive Models for Brain Machine Interface Designs

Authors: Vickneswaran Jeyabalan, Andrews Samraj, Loo Chu Kiong

Abstract:

The noteworthy point in the advancement of Brain Machine Interface (BMI) research is the ability to accurately extract features of the brain signals and to classify them into targeted control action with the easiest procedures since the expected beneficiaries are of disabled. In this paper, a new feature extraction method using the combination of adaptive band pass filters and adaptive autoregressive (AAR) modelling is proposed and applied to the classification of right and left motor imagery signals extracted from the brain. The introduction of the adaptive bandpass filter improves the characterization process of the autocorrelation functions of the AAR models, as it enhances and strengthens the EEG signal, which is noisy and stochastic in nature. The experimental results on the Graz BCI data set have shown that by implementing the proposed feature extraction method, a LDA and SVM classifier outperforms other AAR approaches of the BCI 2003 competition in terms of the mutual information, the competition criterion, or misclassification rate.

Keywords: Adaptive autoregressive, adaptive bandpass filter, brain machine Interface, EEG, motor imaginary.

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94 The Computer Multimedia Instruction Package for Welding and Brazing

Authors: C. Mongkol

Abstract:

The objective of this project is to produce computer assisted instruction(CAI) for welding and brazing in order to determine the efficiency of the instruction package and the study accomplishment of learner by studying through computer assisted instruction for welding and brazing it was examined through the target group surveyed from the 30 students studying in the two year of 5-year-academic program, department of production technology education, faculty of industrial education and technology, king mongkut-s university of technology thonburi. The result of the research indicated that the media evaluated by experts and subject matter quality evaluation of computer assisted instruction for welding and brazing was in line for the good criterion. The mean of score evaluated before the study, during the study and after the study was 34.58, 83.33 and 83.43, respectively. The efficiency of the lesson was 83.33/83.43 which was higher than the expected value, 80/80. The study accomplishment of the learner, who utilizes computer assisted instruction for welding and brazing as a media, was higher and equal to the significance statistical level of 95%. The value was 1.669 which was equal to 35.36>1.669. It could be summarized that computer assisted instruction for welding and brazing was the efficient media to use for studying and teaching.

Keywords: Computer Assisted Instruction, Achievement, Efficiency of the lesson, Evaluation

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93 Hybrid Anomaly Detection Using Decision Tree and Support Vector Machine

Authors: Elham Serkani, Hossein Gharaee Garakani, Naser Mohammadzadeh, Elaheh Vaezpour

Abstract:

Intrusion detection systems (IDS) are the main components of network security. These systems analyze the network events for intrusion detection. The design of an IDS is through the training of normal traffic data or attack. The methods of machine learning are the best ways to design IDSs. In the method presented in this article, the pruning algorithm of C5.0 decision tree is being used to reduce the features of traffic data used and training IDS by the least square vector algorithm (LS-SVM). Then, the remaining features are arranged according to the predictor importance criterion. The least important features are eliminated in the order. The remaining features of this stage, which have created the highest level of accuracy in LS-SVM, are selected as the final features. The features obtained, compared to other similar articles which have examined the selected features in the least squared support vector machine model, are better in the accuracy, true positive rate, and false positive. The results are tested by the UNSW-NB15 dataset.

Keywords: Intrusion detection system, decision tree, support vector machine, feature selection.

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92 A Comparison of SVM-based Criteria in Evolutionary Method for Gene Selection and Classification of Microarray Data

Authors: Rameswar Debnath, Haruhisa Takahashi

Abstract:

An evolutionary method whose selection and recombination operations are based on generalization error-bounds of support vector machine (SVM) can select a subset of potentially informative genes for SVM classifier very efficiently [7]. In this paper, we will use the derivative of error-bound (first-order criteria) to select and recombine gene features in the evolutionary process, and compare the performance of the derivative of error-bound with the error-bound itself (zero-order) in the evolutionary process. We also investigate several error-bounds and their derivatives to compare the performance, and find the best criteria for gene selection and classification. We use 7 cancer-related human gene expression datasets to evaluate the performance of the zero-order and first-order criteria of error-bounds. Though both criteria have the same strategy in theoretically, experimental results demonstrate the best criterion for microarray gene expression data.

Keywords: support vector machine, generalization error-bound, feature selection, evolutionary algorithm, microarray data

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91 Modified Fuzzy ARTMAP and Supervised Fuzzy ART: Comparative Study with Multispectral Classification

Authors: F.Alilat, S.Loumi, H.Merrad, B.Sansal

Abstract:

In this article a modification of the algorithm of the fuzzy ART network, aiming at returning it supervised is carried out. It consists of the search for the comparison, training and vigilance parameters giving the minimum quadratic distances between the output of the training base and those obtained by the network. The same process is applied for the determination of the parameters of the fuzzy ARTMAP giving the most powerful network. The modification consist in making learn the fuzzy ARTMAP a base of examples not only once as it is of use, but as many time as its architecture is in evolution or than the objective error is not reached . In this way, we don-t worry about the values to impose on the eight (08) parameters of the network. To evaluate each one of these three networks modified, a comparison of their performances is carried out. As application we carried out a classification of the image of Algiers-s bay taken by SPOT XS. We use as criterion of evaluation the training duration, the mean square error (MSE) in step control and the rate of good classification per class. The results of this study presented as curves, tables and images show that modified fuzzy ARTMAP presents the best compromise quality/computing time.

Keywords: Neural Networks, fuzzy ART, fuzzy ARTMAP, Remote sensing, multispectral Classification.

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90 Handwriting Velocity Modeling by Artificial Neural Networks

Authors: Mohamed Aymen Slim, Afef Abdelkrim, Mohamed Benrejeb

Abstract:

The handwriting is a physical demonstration of a complex cognitive process learnt by man since his childhood. People with disabilities or suffering from various neurological diseases are facing so many difficulties resulting from problems located at the muscle stimuli (EMG) or signals from the brain (EEG) and which arise at the stage of writing. The handwriting velocity of the same writer or different writers varies according to different criteria: age, attitude, mood, writing surface, etc. Therefore, it is interesting to reconstruct an experimental basis records taking, as primary reference, the writing speed for different writers which would allow studying the global system during handwriting process. This paper deals with a new approach of the handwriting system modeling based on the velocity criterion through the concepts of artificial neural networks, precisely the Radial Basis Functions (RBF) neural networks. The obtained simulation results show a satisfactory agreement between responses of the developed neural model and the experimental data for various letters and forms then the efficiency of the proposed approaches.

Keywords: ElectroMyoGraphic (EMG) signals, Experimental approach, Handwriting process, Radial Basis Functions (RBF) neural networks, Velocity Modeling.

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89 Enhancing Human Mobility Exoskeleton Comfort Using Admittance Controller

Authors: Alexandre Rabaseda, Emelie Seguin, Marc Doumit

Abstract:

Human mobility exoskeletons have been in development for several years and are becoming increasingly efficient. Unfortunately, user comfort was not always a priority design criterion throughout their development. To further improve this technology, exoskeletons should operate and deliver assistance without causing discomfort to the user. For this, improvements are necessary from an ergonomic point of view. The device’s control method is important when endeavoring to enhance user comfort. Exoskeleton or rehabilitation device controllers use methods of control called interaction controls (admittance and impedance controls). This paper proposes an extended version of an admittance controller to enhance user comfort. The control method used consists of adding an inner loop that is controlled by a proportional-integral-derivative (PID) controller. This allows the interaction force to be kept as close as possible to the desired force trajectory. The force-tracking admittance controller modifies the actuation force of the system in order to follow both the desired motion trajectory and the desired relative force between the user and the exoskeleton.

Keywords: Mobility assistive device, exoskeleton, force-tracking admittance controller, user comfort.

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88 Mathematical Modeling to Predict Surface Roughness in CNC Milling

Authors: Ab. Rashid M.F.F., Gan S.Y., Muhammad N.Y.

Abstract:

Surface roughness (Ra) is one of the most important requirements in machining process. In order to obtain better surface roughness, the proper setting of cutting parameters is crucial before the process take place. This research presents the development of mathematical model for surface roughness prediction before milling process in order to evaluate the fitness of machining parameters; spindle speed, feed rate and depth of cut. 84 samples were run in this study by using FANUC CNC Milling α-Τ14ιE. Those samples were randomly divided into two data sets- the training sets (m=60) and testing sets(m=24). ANOVA analysis showed that at least one of the population regression coefficients was not zero. Multiple Regression Method was used to determine the correlation between a criterion variable and a combination of predictor variables. It was established that the surface roughness is most influenced by the feed rate. By using Multiple Regression Method equation, the average percentage deviation of the testing set was 9.8% and 9.7% for training data set. This showed that the statistical model could predict the surface roughness with about 90.2% accuracy of the testing data set and 90.3% accuracy of the training data set.

Keywords: Surface roughness, regression analysis.

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87 On the Performance of Information Criteria in Latent Segment Models

Authors: Jaime R. S. Fonseca

Abstract:

Nevertheless the widespread application of finite mixture models in segmentation, finite mixture model selection is still an important issue. In fact, the selection of an adequate number of segments is a key issue in deriving latent segments structures and it is desirable that the selection criteria used for this end are effective. In order to select among several information criteria, which may support the selection of the correct number of segments we conduct a simulation study. In particular, this study is intended to determine which information criteria are more appropriate for mixture model selection when considering data sets with only categorical segmentation base variables. The generation of mixtures of multinomial data supports the proposed analysis. As a result, we establish a relationship between the level of measurement of segmentation variables and some (eleven) information criteria-s performance. The criterion AIC3 shows better performance (it indicates the correct number of the simulated segments- structure more often) when referring to mixtures of multinomial segmentation base variables.

Keywords: Quantitative Methods, Multivariate Data Analysis, Clustering, Finite Mixture Models, Information Theoretical Criteria, Simulation experiments.

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86 Study on Electrohydrodynamic Capillary Instability with Heat and Mass Transfer

Authors: D. K. Tiwari, Mukesh Kumar Awasthi, G. S. Agrawal

Abstract:

The effect of an axial electric field on the capillary instability of a cylindrical interface in the presence of heat and mass transfer has been investigated using viscous potential flow theory. In viscous potential flow, the viscous term in Navier-Stokes equation vanishes as vorticity is zero but viscosity is not zero. Viscosity enters through normal stress balance in the viscous potential flow theory and tangential stresses are not considered. A dispersion relation that accounts for the growth of axisymmetric waves is derived and stability is discussed theoretically as well as numerically. Stability criterion is given by critical value of applied electric field as well as critical wave number. Various graphs have been drawn to show the effect of various physical parameters such as electric field, heat transfer capillary number, conductivity ratio, permittivity ratio on the stability of the system. It has been observed that the axial electric field and heat and mass transfer both have stabilizing effect on the stability of the system.

Keywords: Capillary instability, Viscous potential flow, Heat and mass transfer, Axial electric field.

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85 Analysing the Elementary Science and Technology Coursebook and Student Workbook in Terms of Constructivism

Authors: Nil Duban

Abstract:

The curriculum of the primary school science course was redesigned on the basis of constructivism in 2005-2006 academic years, in Turkey. In this context, the name of this course has been changed as “Science and Technology"; and both content and course books, students workbooks for this course have been redesigned in light of constructivism. The aim of this study is to determine whether the Science and Technology course books and student work books for primary school 5th grade are appropriate for the constructivism by evaluating them in terms of the fundamental principles of constructivism. In this study, out of qualitative research methods, documentation technique (i.e. document analysis) is applied; while selecting samples, criterion-sampling is used out of purposeful sampling techniques. When the Science and Technology course book and workbook for the 5th grade in primary education are examined, it is seen that both books complete each other in certain areas. Consequently, it can be claimed that in spite of some inadequate and missing points in the course book and workbook of the primary school Science and Technology course for the 5th grade students, these books are attempted to be designed in terms of the principles of constructivism. To overcome the inadequacies in the books, it can be suggested to redesign them. In addition to them, not to ignore the technology dimension of the course, the activities that encourage the students to prepare projects using technology cycle should be included.

Keywords: Constructivism, coursebooks, science and technology education.

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84 Secure Power Systems Against Malicious Cyber-Physical Data Attacks: Protection and Identification

Authors: Morteza Talebi, Jianan Wang, Zhihua Qu

Abstract:

The security of power systems against malicious cyberphysical data attacks becomes an important issue. The adversary always attempts to manipulate the information structure of the power system and inject malicious data to deviate state variables while evading the existing detection techniques based on residual test. The solutions proposed in the literature are capable of immunizing the power system against false data injection but they might be too costly and physically not practical in the expansive distribution network. To this end, we define an algebraic condition for trustworthy power system to evade malicious data injection. The proposed protection scheme secures the power system by deterministically reconfiguring the information structure and corresponding residual test. More importantly, it does not require any physical effort in either microgrid or network level. The identification scheme of finding meters being attacked is proposed as well. Eventually, a well-known IEEE 30-bus system is adopted to demonstrate the effectiveness of the proposed schemes.

Keywords: Algebraic Criterion, Malicious Cyber-Physical Data Injection, Protection and Identification, Trustworthy Power System.

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83 Assessment of Water Pollution of Kowsar Dam Reservoir

Authors: Mohammad Mahdi Jabbari, Fardin Boustani

Abstract:

The reservoir of Kowsar dam supply water for different usages such as aquaculture farms , drinking, agricultural and industrial usages for some provinces in south of Iran. The Kowsar dam is located next to the city of Dehdashat in Kohgiluye and Boyerahmad province in southern Iran. There are some towns and villages on the Kowsar dam watersheds, which Dehdasht and Choram are the most important and populated twons in this area, which can to be sources of pollution for water reservoir of the Kowsar dam . This study was done to determine of water pollution of the Kowsar dam reservoir which is one of the most important water resources of Kohkiloye and Boyerahmad and Bushehr provinces in south-west Iran. In this study , water samples during 12 months were collected to examine Biochemical Oxygen Demand (BOD) and Dissolved Oxygen(DO) as a criterion for evaluation of water pollution of the reservoir. In summary ,the study has shown Maximum, average and minimum levels of BOD have observed 25.9 ,9.15 and 2.3 mg/L respectively and statistical parameters of data such as standard deviation , variance and skewness have calculated 7.88, 62 and 1.54 respectively. Finally the results were compared with Iranian national standards. Among the analyzed samples, as the maximum value of BOD (25.9 mg/L) was observed at the May 2010 , was within the maximum admissible limits by the Iranian standards.

Keywords: Kowsar dam, Biochemical Oxygen Demand, water pollution

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82 The Study of the Variability of Anticipatory Postural Adjustments in Recurrent Non-specific LBP Patients

Authors: Rosita Hedayati , Sedighe Kahrizi , Mohammad Parnianpour , Fariba Bahrami , Anoshirvan Kazemnejad

Abstract:

The study of the variability of the postural strategies in low back pain patients, as a criterion in evaluation of the adaptability of this system to the environmental demands is the purpose of this study. A cross-sectional case-control study was performed on 21 recurrent non-specific low back pain patients and 21 healthy volunteers. The electromyography activity of Deltoid, External Oblique (EO), Transverse Abdominis/Internal Oblique (TrA/IO) and Erector Spine (ES) muscles of each person was recorded in 75 rapid arm flexion with maximum acceleration. Standard deviation of trunk muscles onset relative to deltoid muscle onset were statistically analyzed by MANOVA . The results show that chronic low back pain patients exhibit less variability in their anticipatory postural adjustments (APAs) in comparison with the control group. There is a decrease in variability of postural control system of recurrent non-specific low back pain patients that can result in the persistence of pain and chronicity by decreasing the adaptability to environmental demands.

Keywords: EMG Onset Latency, Variability, Posture, Non - specific Low Back Pain

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81 Viscous Potential Flow Analysis of Electrohydrodynamic Capillary Instability through Porous Media

Authors: Mukesh Kumar Awasth, Mohammad Tamsir

Abstract:

The effect of porous medium on the capillary instability of a cylindrical interface in the presence of axial electric field has been investigated using viscous potential flow theory. In viscous potential flow, the viscous term in Navier-Stokes equation vanishes as vorticity is zero but viscosity is not zero. Viscosity enters through normal stress balance in the viscous potential flow theory and tangential stresses are not considered. A dispersion relation that accounts for the growth of axisymmetric waves is derived and stability is discussed theoretically as well as numerically. Stability criterion is given by critical value of applied electric field as well as critical wave number. Various graphs have been drawn to show the effect of various physical parameters such as electric field, viscosity ratio, permittivity ratio on the stability of the system. It has been observed that the axial electric field and porous medium both have stabilizing effect on the stability of the system.

Keywords: Capillary instability, Viscous potential flow, Porous media, Axial electric field.

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80 Phytoremediation Potential of Native Plants Growing on a Heavy Metals Contaminated Soil of Copper mine in Iran

Authors: B. Lorestani, M. Cheraghi, N. Yousefi

Abstract:

A research project dealing with the phytoremediation of a soil polluted by some heavy metals is currently running. The case study is represented by a mining area in Hamedan province in the central west part of Iran. The potential of phytoextraction and phytostabilization of plants was evaluated considering the concentration of heavy metals in the plant tissues and also the bioconcentration factor (BCF) and the translocation factor (TF). Also the several established criteria were applied to define hyperaccumulator plants in the studied area. Results showed that none of the collected plant species were suitable for phytoextraction of Cu, Zn, Fe and Mn, but among the plants, Euphorbia macroclada was the most efficient in phytostabilization of Cu and Fe, while, Ziziphora clinopodioides, Cousinia sp. and Chenopodium botrys were the most suitable for phytostabilization of Zn and Chondrila juncea and Stipa barbata had the potential for phytostabilization of Mn. Using the most common criterion, Euphorbia macroclada and Verbascum speciosum were Fe hyperaccumulator plants. Present study showed that native plant species growing on contaminated sites may have the potential for phytoremediation.

Keywords: Bioconcentration factor, Heavy metals, Hyperaccumulator, Phytoremediation, Translocation factor

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79 Protein Graph Partitioning by Mutually Maximization of cycle-distributions

Authors: Frank Emmert Streib

Abstract:

The classification of the protein structure is commonly not performed for the whole protein but for structural domains, i.e., compact functional units preserved during evolution. Hence, a first step to a protein structure classification is the separation of the protein into its domains. We approach the problem of protein domain identification by proposing a novel graph theoretical algorithm. We represent the protein structure as an undirected, unweighted and unlabeled graph which nodes correspond the secondary structure elements of the protein. This graph is call the protein graph. The domains are then identified as partitions of the graph corresponding to vertices sets obtained by the maximization of an objective function, which mutually maximizes the cycle distributions found in the partitions of the graph. Our algorithm does not utilize any other kind of information besides the cycle-distribution to find the partitions. If a partition is found, the algorithm is iteratively applied to each of the resulting subgraphs. As stop criterion, we calculate numerically a significance level which indicates the stability of the predicted partition against a random rewiring of the protein graph. Hence, our algorithm terminates automatically its iterative application. We present results for one and two domain proteins and compare our results with the manually assigned domains by the SCOP database and differences are discussed.

Keywords: Graph partitioning, unweighted graph, protein domains.

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78 Evolving a Fuzzy Rule-Base for Image Segmentation

Authors: A. Borji, M. Hamidi

Abstract:

A new method for color image segmentation using fuzzy logic is proposed in this paper. Our aim here is to automatically produce a fuzzy system for color classification and image segmentation with least number of rules and minimum error rate. Particle swarm optimization is a sub class of evolutionary algorithms that has been inspired from social behavior of fishes, bees, birds, etc, that live together in colonies. We use comprehensive learning particle swarm optimization (CLPSO) technique to find optimal fuzzy rules and membership functions because it discourages premature convergence. Here each particle of the swarm codes a set of fuzzy rules. During evolution, a population member tries to maximize a fitness criterion which is here high classification rate and small number of rules. Finally, particle with the highest fitness value is selected as the best set of fuzzy rules for image segmentation. Our results, using this method for soccer field image segmentation in Robocop contests shows 89% performance. Less computational load is needed when using this method compared with other methods like ANFIS, because it generates a smaller number of fuzzy rules. Large train dataset and its variety, makes the proposed method invariant to illumination noise

Keywords: Comprehensive learning Particle Swarmoptimization, fuzzy classification.

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77 Influence of Fiber Packing on Transverse Plastic Properties of Metal Matrix Composites

Authors: Mohammad Tahaye Abadi

Abstract:

The present paper concerns with the influence of fiber packing on the transverse plastic properties of metal matrix composites. A micromechanical modeling procedure is used to predict the effective mechanical properties of composite materials at large tensile and compressive deformations. Microstructure is represented by a repeating unit cell (RUC). Two fiber arrays are considered including ideal square fiber packing and random fiber packing defined by random sequential algorithm. The micromechanical modeling procedure is implemented for graphite/aluminum metal matrix composite in which the reinforcement behaves as elastic, isotropic solids and the matrix is modeled as an isotropic elastic-plastic solid following the von Mises criterion with isotropic hardening and the Ramberg-Osgood relationship between equivalent true stress and logarithmic strain. The deformation is increased to a considerable value to evaluate both elastic and plastic behaviors of metal matrix composites. The yields strength and true elastic-plastic stress are determined for graphite/aluminum composites.

Keywords: Fiber packing, metal matrix composites, micromechanics, plastic deformation, random

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