|Title: Channel Capacity of MIMO FSO System under Strong Turbulent Condition|
|Author(s): Bobby Barua, Dalia Barua|
|Pages: 1-5||Paper ID: 113102-9494 IJECS-IJENS||Published: April, 2011|
Abstract: Free Space Optics (FSO) or optical wireless communication is a promising solution for the need to very high data rate point-to-point communication. In FSO communication links, atmospheric turbulence causes fluctuations in both the intensity and the phase of the received light signal, impairing link performance. This intensity fluctuation, also known as scintillation is one of the most important factors that degrade the performance of an FSO communication link even under the clear sky condition. This paper investigates the use of multiple lasers and multiple apertures to mitigate the effects of scintillation. Also an analytical approach is presented to evaluate the channel capacity of a free space optical link using Q-ary optical PPM under strong atmospheric turbulent condition. In this view, we propose design rules for optimal channel capacity of the system.
|Keywords: Free space optics (FSO), pulse position modulation (PPM), probability of density function (PDF), channel capacity.|
|Full Text (.pdf) | 475 KB|
|Title: Performance and Complexity Comparison of Channel Estimation Algorithms for OFDM System|
|Author(s): Saqib Saleem, Qamar-Ul-Islam|
|Pages: 6-11||Paper ID: 113702-4949 IJECS-IJENS||Published: April, 2011|
Abstract: To mitigate the multipath delay effect of the received signal, the information of the time-varying channel is required at the receiver to determine the equalizer co-efficients. In this paper two basic algorithms, known as Linear Minimum Mean Square (LMMSE) and Least Square Error (LSE), are discussed which make use of the channel statistics in time domain. To reduce the complexity, different variants of these algorithms are also discussed. Channel Impulse Response (CIR) samples and channel taps are used to compare the performance and complexity. MATLAB simulations are carried out to compare the performance in terms of Mean Square Error (MSE) and Symbol Error Rate (SER) of these algorithms for different modulation techniques.
|Keywords: Mean Square Error, Channel Impulse Response, Least Square Error, Minimum Mean Square Error, Channel Taps.|
|Full Text (.pdf) | 822 KB|
|Title: Fuzzy Logic Controller for BLDC Permanent Magnet Motor Drives|
|Author(s): Tan Chee Siong, Baharuddin Ismail, Siti Fatimah Siraj, Mohd Fayzul Mohammed|
|Pages: 12-17||Paper ID: 114202-6464 IJECS-IJENS||Published: April, 2011|
Abstract: This paper presents a fuzzy logic controller for brushless direct current (BLDC) permanent magnet motor drives. Initially a fuzzy logic controller is developed using MATLAB Fuzzy-Logic Toolbox and then inserted into the Simulink model. The dynamic characteristics of the brushless DC motor such as speed, torque, current and voltage of the inverter components are observed and analyzed using the developed MATLAB model. In order to verify the effectiveness of the controller, the simulation results are compared with TMS320F2808 DSP experimental results. The simulation and experimental results show that the brushless direct current motor (BLDC) is successfully and efficiently controlled by the Fuzzy logic controller.
|Keywords: Fuzzy logic controller, BLDC motor drives, Digital Signal Processing.|
|Full Text (.pdf) | 951 KB|
|Title: Optimized Selection Sort Algorithm is faster than Insertion Sort Algorithm: a Comparative Study|
|Author(s): Sultanullah Jadoon, Salman Faiz Solehria, Mubashir Qayum|
|Pages: 18-23||Paper ID: 115002-3838 IJECS-IJENS||Published: April, 2011|
Abstract: Optimized Selection Sort Algorithm is a new sorting algorithm that has been developed to address the shortcomings of the current popular sorting algorithms. The goal of this research is to perform an extensive empirical analysis of Optimized Selection Sort against Selection Sort and Insertion Sort Algorithms. The results proved that Optimized Selection Sort is much more efficient than Selection Sort Algorithm; Furthermore analysis supports the fact that Optimized Selection Sort is better than Insertion Sort in worst case scenario.
|Keywords: Optimized Selection Sort, Worst Case, Efficiency, Sorting Algorithm.|
|Full Text (.pdf) | 590 KB|
|Title: Matlab/Simulink Models For Typical Soft Starting Means For A DC Motor|
|Author(s): Maamar Taleb|
|Pages: 24-29||Paper ID: 115302-6464 IJECS-IJENS||Published: April, 2011|
Abstract: Three possible conventional means may usually be used to control or monitor the level of the armature current when starting a dc motor. The three possible means are: 1. Use of a gradually decreasing tapped resistance between the supply voltage and the motor armature circuit. 2. Use of a chopper circuit between the supply voltage and the motor armature circuit. 3. Use of a variable DC voltage source. Matlab/Simulink models of the three means are developed and presented in this article. The third mean seems to own certainly superiority when compared to the two first means.
|Keywords: DC Motor Starter, Step-up Converter, AC/DC Converter, Matlab/Simulink Models.|
|Full Text (.pdf) | 403 KB|
|Title: Object Oriented System of E-Learning (OOSEL)|
|Author(s): Hamid Jan, Inayat Ullah, Zanobia Nisar|
|Pages: 30-34||Paper ID: 115402-3636 IJECS-IJENS||Published: April, 2011|
Abstract: Currently the electronic means of supporting learning has obtained a wider ever acceptance. One of the main task of system of operations and support learning is to organize the process of checking student’s knowledge. The system of learning is required to perform more functions due to stringent requirements over the time, which can be solved by constructing an optimum architecture. We in this paper are proposing the object oriented technique “OOSEL” for solving the problems of checking the student knowledge.
|Keywords: E-Learning System, Constructors, Objects, Class, Task.|
|Full Text (.pdf) | 422 KB|
|Title: Vehicle Accident Alert and Locator (VAAL)|
|Author(s): Victor Olugbemiga MATTHEWS, Emmanuel ADETIBA|
|Pages: 35-38||Paper ID: 116102-2929 IJECS-IJENS||Published: April, 2011|
Abstract: An emergency is a deviation from planned or expected behaviour or a course of event that endangers or adversely affects people, property, or the environment. This paper reports a complete research work in accident (automobile) emergency alert situation. The authors were able to programme a GPS / GSM module incorporating a crash detector to report automatically via the GSM communication platform (using SMS messaging) to the nearest agencies such as police posts, hospitals, fire services etc, giving the exact position of the point where the crash had occurred. This will allow early response and rescue of accident victims; saving lives and properties. The paper reports its experimental results, gives appropriate conclusions and recommendations.
|Keywords: Accident Alert, Crash Detector, Emergency, Location Based Services, GPS/ GSM, VAAL.|
|Full Text (.pdf) | 640 KB|
|Title: Model of Binary Cycle Power Plant using Brine as Thermal Energy Sources and Development Potential in Sibayak|
|Author(s): Bambang Teguh P., Suyanto, MD. Trisno|
|Pages: 39-47||Paper ID: 116202-7373 IJECS-IJENS||Published: April, 2011|
Abstract: Currently, 100% of brine at direct-steam geothermal power plant is injected into injection wells. Injected brine generally has a temperature higher than 100oC and mass flow rate around hundred of ton/hour. The content of rejected thermal energy is around hundred MW. Binary cycle plant may be advantageous technology to recover this energy waste. In order to study the implementation above technology, it was developed the 2 kW model of binary cycle plant using thermal energy of brine from conventional geothermal power plant. In binary plant, thermal energy of brine is transferred via a heat exchanger to working fluid for use in a fairly conventional Rankine cycle. The power cycle consists of an evaporator, a turbine-generator, a condenser, and feed pump. Other equipment is cooling tower to serve the condenser cooling water. The working fluid used in this plant is n-pentane to achieve a good thermodynamic match to the particular characteristics of brine, especially brine temperature. This paper presents the design of model 2 kW binary cycle plant and development potential in Sibayak. From design analysis the heat exchangers equipments to be used are 56.31 kW shell and tube evaporator, 53.68 kW shell and tube condenser. The turbine design is single stage impulse turbine with five convergent nozzles, 382.3 mm rotor diameter, 60 number of blade, 16.5 mm height of blade, and 10 mm width of blade. This turbine is designed to operate at 3000 rpm and 65.6% turbine efficiency. Experimental result showed that the system has successfully produced 1.2 kWe. There is 8.5% different in efficiency lower than design condition The method of design, experimental result and future development potential in Sibayak will discuss in this paper.
|Keywords: Geothermal, binary cycle, n-pentane, thermal waste, brine, heat exchangers, turbine, Sibayak.|
|Full Text (.pdf) | 794 KB|
|Title: Estimation of Solar Power Efficiency in Day Time at Different Temperatures|
|Author(s): M. Arshad Javaid, Mukhtar-ul-Hassan, M. Shuja Khan, S. F. Shaukat|
|Pages: 48-52||Paper ID: 116802-9494 IJECS-IJENS||Published: April, 2011|
Abstract: An extensive research has been carried out on the solar electric power of individual solar module throughout the day at different temperatures. Experiments have been performed at PCSIR Laboratory, Lahore Pakistan. Different calculations have been made in terms of AC/DC current, voltage and output power and then efficiency has been measured at different time scale. There were total 15 modules installed and each module has 36 photovoltaic cells. The results show that efficiency of solar cell increases with increasing the solar intensity and also indicates that short circuit current increases by increasing the solar intensity. It has also been observed that the modules can be connected in series, parallel or series-parallel in order to get the desired power. For each experiment conducted, the load connected at output is in the form of bulb of different watts, 10, 15 25, 40,50,60,75,100 and 200 watt with tungsten filament. The conclusions presented in this paper will stimulate and direct future research work for maintaining the clean energy using photovoltaic cells.
|Keywords: Renewable Technology, Power Efficiency, Solar Module, Photovoltaic Cell.|
|Full Text (.pdf) | 442 KB|
|Title: Low Voltage Ride through Strategies for SCIG Wind Turbines Interconnected Grid|
|Author(s): Omar Noureldeen|
|Pages: 53-58||Paper ID: 117502-6565 IJECS-IJENS||Published: April, 2011|
Abstract: The ability of the wind power plant to stay connected during grid disturbances is important to avoid a cascading effect due to lack of power. Making it necessary to introduce new code of practice, the grid operators require that wind turbines stay connected to the grid during voltage dips. Low Voltage Ride Through (LVRT) has emerged as a new requirement that system operators demand to wind turbines. This paper analyzes the extent to which the LVRT capability of wind farms using squirrel cage generators can be enhanced by the use of a Static Synchronous Compensator STATCOM. The ability of wind farms to stay connected to grid during LVRT is investigated based on E-ON NETZ grid code. A simulation model of 9 MW wind farm interconnected grid is carried out using the MATLAB SimPowerSystems toolbox.
|Keywords: SCIG, STATCOM, Voltage Dips, Wind Farm, Grid Code.|
|Full Text (.pdf) | 525 KB|
|Title: A Model for Least Distance Protocol in MANET Using Artificial Intelligence Search Techniques|
|Author(s): Khondker Shajadul Hasan, Radia Abdul Wahab, Munawwar Mahmud Sohul|
|Pages: 59-66||Paper ID: 117902-4545 IJECS-IJENS||Published: April, 2011|
Abstract: As mobile adhoc networks operate with nodes carrying small amount of energy, reducing energy consumption is a major issue in adhoc networks. The paper discusses a protocol along with its implementation which incorporates Artificial intelligence search techniques, namely A* search and Dijkstra’s algorithm to reduce the distance traversed by both the data and the control information. The transmission path is determined by the means of A* search, which gives the shortest path possible. This greatly reduces the distance traversed. This paper also focuses on the performance of this protocol compared with swarm intelligence which is another artificial intelligence protocol implemented by MANET (mobile adhoc network). A collection of proposed transmission protocols’ characteristics has been presented in this paper. An extensive empirical study has been carried out to validate the protocol’s performance.
|Keywords: Mobile Adhoc Networks, Multi-hopping, Grid system, A* search, Dijkstra’s Algorithm, Swarm intelligence, Path cost.|
|Full Text (.pdf) | 653 KB|
|Title: Non Linear Model : Logit Model Application for The Study of Catalyst Dosage Effect in Methylene Blue Photodegradation|
|Author(s): J. Nugraha, I. Fatimah|
|Pages: 67-71||Paper ID: 118102-7373 IJECS-IJENS||Published: April, 2011|
Abstract: This paper present the role of Logit Model in optimizing photocatalyst dosage in methylene blue (MB) photodegradation system by using prepared photocatalyst. The model was constructed by measuring the percentage of target molecule degraded in the system by using linear and logistic regression. The deviation of the model used to compare the goodness of fit of the three models. The study on the most appropriate model for predicting the effect of catalyst dosage to the MB concentration is discussed.
|Keywords: Logit Model, Kinetics data, Photodegradation, Methylene Blue.|
|Full Text (.pdf) | 232 KB|
|Title: Simulation of Visual Servo Control with Kalman Filter on Puma 560|
|Author(s): Noor Cholis Basjaruddin|
|Pages: 72-77||Paper ID: 118202-9797 IJECS-IJENS||Published: April, 2011|
Abstract: Pose estimation is important step on Position-Based Visual Servo Control System building. This paper presents a vision based position sensor system which provide three dimensional (3D) relative position and orientation (pose) of an arbitary moving object with respect to end-effector mounted camera. Kalman filtering is applied to vision measurement from a single end-effector mounted camera to implement an implicit real-time solution of the photogrametic equations and to provide significant temporal filtering of the resulting motion parameters. PUMA 560 robot is selected to implement this simulation. The kinematic and dynamic data of PUMA 560 is collected from references. Simulation is build with Matlab and Robotic Toolbox. Results of computer simulation demonstrate the successful operation of the control strategy and Kalman filter success to estimate relative pose.
|Keywords: Visual servo control system; position-based visual control system; Kalman Filter; pose estimation.|
|Full Text (.pdf) | 847 KB|
|Title: Evolution and Standardization of Romanized Bangla for Computers and Mobile Phone Text|
|Author(s): Shahriar Khan|
|Pages: 78-85||Paper ID: 116702-8484 IJECS-IJENS||Published: April, 2011|
Abstract: Romanization Bangla, or usage of the Latin script for Bangla, started mostly with the British rule of India. In spite of more attempts at standardization in the 1960s, Romanized Bangla only gained popularity, with the emergence of the internet, and mobile phone text. Since users are mostly the younger generation, in email, SMS, and chatrooms, they are largely determining the evolution of the spelling in the Romanization. Other users are mobile phone companies, and official organizations sending out advertisements and public messages. Without us being aware of it, there is an evolution towards some common spelling standards. This paper collected a database of messages over a year, mostly from official organizations and mobile phone operators. It was seen that about 50 % of the words have already been standardized, with popular agreement on the spelling. More words will become standardized over the next few years. Some recommendations were made regarding the control of the standards. This paper is applicable to other native languages of the world, which are becoming Romanized owing to mobile phone penetration.
|Keywords: Bengali, Bangla, English, alphabet, standardization, Romanization, Transcription, Transliteration, Spelling.|
|Full Text (.pdf) | 550 KB|
|Title: A Step towards an Easy Interconversion of Various Number Systems|
|Author(s): Shahid Latif, Rahat Ullah, Hamid Jan|
|Pages: 86-91||Paper ID: 1111502-7373 IJECS-IJENS||Published: April, 2011|
Abstract: Any system that is used for naming or representing numbers is a number system, also known as numeral system. The modern civilization is familiar with decimal number system using ten digits. However digital devices and computers use binary number system instead of decimal number system, using only two digits namely, 0 and 1 based on the fundamental concept of the decimal number system. Various other number systems also used this fundamental concept of decimal number system, for example octal number system and hexadecimal number systems using eight and sixteen digits respectively. The knowledge of number systems and their inter conversion is essential for understanding of computers. More over, successful programming for digital devices requires a precise understanding of data formats, number systems and their inter conversion. The inter conversion (a process in which things are each converted into the other) of number system requires allot of time and techniques to expertise. In this paper the interconversion of four most common number systems is taken under the consideration in tabulated form. It is a step towards the easy interconversion of these number systems to understand as well as memorise it. The four number systems are binary, octal, decimal and hexadecimal.
|Keywords: Digital, Binary, octal, hexadecimal, bases or radix, inter conversion.|
|Full Text (.pdf) | 285 KB|