Abstract: This paper provides a new approach for analysing social networks that are formed around e-Learning environments. A combination of three methods (Social Network Analysis, Collectivist Online Learning Environment Survey, Attitudes Towards Thinking and Learning Survey) was applied to a case study of an online course. Following this, correlations were carried out between the students’ responses to the questionnaires and their actual social interaction in the e-learning course. Based on these results we were able to provide insights on methods that can be used to predict the students’ social interactions when they take part in communication activities in e-Learning environments.

Abstract: A photovoltaic system connected to the grid is constituted by two main parts: a solar cell and a power converter DC-AC. The impedance adaptation between the two parties is a technological problem that essentially means the transfer of maximum power of  PV generator to the grid. In this paper, a new technique for nonlinear control of power converter DC-AC is presented. This converter is built on two stages: a DC-DC stage and a DC-AC stage. The two blocks are bound by a DC voltage intermediate bus. The control objective is threefold: i) control the input voltage of the converter to find the MPP (maximum power point), ii) regulating the DC bus voltage, iii) generate a sinusoidal current at industrial frequency that will be injected into the network with a power factor near unity. The synthesis of controllers was performed using the technique of backstepping nonlinear control. A detailed analysis of the stability control system is presented. The performance of controllers has been validated by numerical simulation in MATLAB / SIMULINK.

Abstract: Grounding grid performance can be measured in terms of grounding resistance, but it is preferable to include the distribution of surface potential and, subsequently, the touch and step voltages over the area above the substation ground grid and beyond. Two methods are used in this paper to compute the grounding resistance (Rg) and the earth surface potential (ESP) due to discharging current into grounding grids. The first one is the charge (current) simulation method (CSM) and the other is the boundary element method (BEM). For BEM, commercial software TOTBEM by university of La Cournia, Spain is used for computing ESP and Rg. The owned FORTRAN code is provided to calculate the ESP and Rg. The soil is assumed to multilayer soil. The paper focuses the comparison between these two methods for calculating ESP and Rg. In case of grounding resistance, a comparison between the two methods results and IEEE Standard formula is presented.

Abstract: Comparisons between the Microsoft Windows and Linux computer operating systems are a long-running discussion topic within the personal computer industry. Throughout the entire period of the Windows 9x systems through the introduction of Windows 7, Windows has retained an extremely large retail sales majority among operating systems for personal desktop use, while Linux has sustained its status as the most prominent Free Software and Open Source operating system. After their initial clash, both operating systems moved beyond the user base of the personal computer market and share a rivalry on a variety of other devices, with offerings for the server and embedded systems markets, and mobile internet access.   Linux and Microsoft Windows differ in philosophy, cost, versatility and stability, with each seeking to improve in their perceived weaker areas. Comparisons of the two operating systems tend to reflect their origins, historic user bases and distribution models.

Abstract: This paper addresses model predictive controller (MPC) as an effective solution for improving the oscillations in a single machine infinite bus (SMIB) power system connected with a FACTS device, unified power flow controller (UPFC). UPFC is mainly used in the transmission systems which can control the power flow by controlling the voltage magnitude, phase angle and impedance. And as a controller, MPC, not only provides the optimal control inputs, but also predicts the system model outputs which enable it to reach the desired goal. So, model predictive unified power flow controller (MPUPFC), a combination of UPFC and MPC along with proper system model parameters can provide a satisfactory performance in damping out the system oscillations making the system stable. Simulation is done in Matlab. Response is shown for 2 different states controlling 4 different control signals of UPFC.

Abstract: The application of human gesture for the interaction between humans and computers is becoming an impressive alternative. Particularly, hand gesture is used as a non-verbal communication between human and machines. Most of recent studies for gesture recognition deal with the shape and movement of hands and also discussion on factor that contributed to the effect of individual factors in arm motions. This paper mainly concentrated on the development of a gesture database to eliminate individual factors, which affect the efficiency of the recognition system. An adaptive gesture recognition system is proposed, and the system could adaptively select the correspond database for the purpose of comparison with the input gesture. A classification algorithm is introduced to investigate whether the individual factor is the primary cause that affects the efficiency of the recognition system. In this study, by examining the characteristics of hand trajectories, motion features are selected and classified by using a statistical approach. The result shows that the individual factor, affects the efficiency of the recognition system. Moreover, the body structure of the performer needs to be considered in the development of the gesture database.

Keywords: Arm motion, human computer interaction, hand trajectories, individual factors, statistical approach, adaptive gesture recognition system, gesture database 

Abstract: The balancing of an Inverted Pendulum by moving a cart in horizontal direction is an orthodox hitch in the region of control theory and engineering. This paper inspects the nonlinear model designing, system analysis, and control implementation of Inverted Pendulum. In order to regulate the whole set-up (i.e., both cart and pendulum), three different control tactics are experimented. These blueprints are designed in such a way that their recitals describe the settled consequences at φ= π. Performances about regulation and control energy specifications of proposed techniques are also examined.

Abstract: Siemens Colombia purchased the polymeric insulator made of HTV- SiR with ATH filler When installed, it was found that some spots occured at insulator surface, leakage current of the insulator due to these spots increased. A sample of this insulator was tested in an artificial chamber for 5000 hours as per IEC specifications. In the chamber Colombian environmental conditions were created and different stresses were applied like High voltage Temperature, UV radiations, artificial rain etc and different tests were performed i.e. FTIR, Hydrophobicity etc. analysis was made from these readings for finding aging of the polymeric insulator.

Abstract: Query Expansion (QE) is one of the most important mechanisms in the Information Retrieval field. A typical short Internet query will go through a process of query refinement to improve its retrieval power. Most of the existing QE techniques suffer from retrieval performance degradation due to imprecise choice of query’s additive terms in the QE process. This paper, introduce QE mechanism involve new expansion process that guided by conceptual representation approach using Concept Mapping tool for expanding the original query, in the context of the utilized corpus. Experimental results, using the MEDLINE test collection data, show the effect of using conceptual representation approach via linguistic and domain based on the recall of retrieval results to enhance its performance.

Abstract: A biometric system provides automatic identification of an individual based on a unique feature or characteristic possessed by that individual. Iris recognition is regarded as one of the most reliable and accurate biometric identification systems available and has been receiving good acceptance in the area. This paper involves the development of iris recognition system using histogram analysis method backed by Local Phase Quantization (LPQ) and Rotation Invariant Local Phase Quantization (RI-LPQ) to verify the uniqueness of human iris as a biometric feature and to test its performances. Iris recognition system consists of the preprocessing process in which it involves image segmentation, feature extraction which includes the RGB image to grayscale and polar transformation. These preprocessed images were then undergone conversion process unto which histogram analysis via LPQ and RI-LPQ are taken place. From the histogram, it will be analyzed to determine and recognize other iris image. In order to implement the recognition, the machine learning process was set to be containing the iris image test database and iris image train database. The distance between the test and train images was measure using K Nearest Neighbor classifier algorithm. The result shows good recognition rate.

Abstract: This paper presents design of Carbon Monoxide (CO) gas detector based on microcontroller performance. The device is embedded with real-time measurement through visualization in Liquid Crystal Display (LCD) and computer monitor. In addition, the data processing utilizes microcontroller ATMEGA8535 under programming environment of CodeVision AVR V2.03.4. The visualization itself is designed based on the combination between programming language of Microsoft Visual Basic ver. 6.0 and C. Data transmission can be very flexible in this case due to the capability standard of microcontroller for communication networks. Also, for one day measurement, the data can be simple stored inside the device. The device has been initially tested in the laboratory on several physical data output. In the implementation, the device has been used to measure the CO level on different locations, such as indoor and outdoor testing and it has shown proper results of measurement.

Abstract: The integration of wavelet theory into soft computing have recently attracted great interest. The first real integration of wavelet into soft computing led to the development of wavelet-networks. In this work, a robust Two Activation Function Wavelet Network (TAFWN) is proposed for the identification of functions with high nonlinearity. The TAFWN is further trained by the least mean squares (LMS) to minimize the mean-squared error. Simulation results are demonstrated to validate the identification ability and efficiency of the proposed network.

Abstract: Nowadays, switched reluctance motors (SRMs) attract more and more attention. Switched reluctance machines have emerged as an important technology in industrial automation. They represent a real alternative to conventional variable speed drives in many applications. It not only features a salient pole stator with concentrated coils, which allows earlier winding and shorter end turns than other types of motors, but also features a salient pole rotor, which has no conductors or magnets and is thus the simplest of all electric machine rotors. Simplicity makes the SRM inexpensive and reliable, and together with its high speed capacity and high torque to inertia ratio, makes it a superior choice in different applications. This research attempts to create a MATLAB model of multiphase SRM using the equations governing the dynamic behavior of linear inductance profile SRM. This simulation model can then be used see the impact of any control system on SRM behavior. Simulation results also prove the exactness of the model.