5975 research outputs found
Sort by
IDDQ Testing of Low Voltage CMOS Operational Transconductance Amplifier
The paper describes the design for testability (DFT) of low voltage two stage operational transconductance amplifiers based on quiescent power supply current (IDDQ) testing. IDDQ testing refers to the integral circuit testing method based upon measurement of steady state power supply current for testing both digital as well as analog VLSI circuit. A built in current sensor, which introduces insignificant performance degradation of the circuit-under-test, has been proposed to monitor the power supply quiescent current changes in the circuit under test. Moreover, the BICS requires neither an external voltage reference nor a current source and able to detect, identify and localize the circuit faults. Hence the BICS requires less area and is more efficient than the conventional current sensors. The testability has also been enhanced in the testing procedure using a simple fault-injection technique. Both bridging and open faults have been analyzed in proposed work by using n-well 0.18µm CMOS technology
Firefly Algorithm to Opmimal Distribution of Reactive Power Compensation Units
The issue of electric power grid mode of optimization is one of the basic directions in power engineering research. Currently, methods other than classical optimization methods based on various bio-heuristic algorithms are applied. The problems of reactive power optimization in a power grid using bio-heuristic algorithms are considered. These algorithms allow obtaining more efficient solutions as well as taking into account several criteria. The Firefly algorithm is adapted to optimize the placement of reactive power sources as well as to select their values. A key feature of the proposed modification of the Firefly algorithm is the solution for the multi-objective optimization problem. Algorithms based on a bio-heuristic process can find a neighborhood of global extreme, so a local gradient descent in the neighborhood is applied for a more accurate solution of the problem. Comparison of gradient descent, Firefly algorithm and Firefly algorithm with gradient descent is carried out
Computer Aided Diagnosis for Screening the Shape and Size of Leukocyte Cell Nucleus based on Morphological Image
Hematology tests are examinations that aim to know the state of blood and its components, one of which is leukocytes. Hematologic examinations such as the number and morphology of blood generally still done manually, especially by a specialist pathologist. Despite the fact that today there is equipment that can identify morphological automatically, but for developing countries like Indonesia, it can only be done in the capital city. Low accuracy due to the differences identified either by doctors or laboratory staff, makes a great reason to use computer assistance, especially with the rapid technological developments at this time. In this paper, we will emphasize our experiment to screen leucocyte cell nucleus by identifying the contours of the cell nucleus, diameter, circumference and area of these cells based on digital image processing techniques, especially using the morphological image. The results obtained are promising for further development in the development of computer-aided diagnosis for identification of leukocytes based on a simple and inexpensive equipmen
Mining the Web Data for Classifying and Predicting Users’ Requests
Consumers are the most important asset of any organization. The commercial activity of an organization booms with the presence of a loyal customer who is visibly content with the product and services being offered. In a dynamic market, understanding variations in client’s behavior can help executives establish operative promotional campaigns. A good number of new consumers are frequently picked up by traders during promotions. Though, several of these engrossed consumers are one-time deal seekers, the promotions undeniably leave a positive impact on sales. It is crucial for traders to identify who can be converted to loyal consumer and then have them patronize products and services to reduce the promotion cost and increase the return on investments. This study integrates a classifier that allows prediction of the type of purchase that a customer would make, as well as the number of visits that he/she would make during a year. The proposed model also creates outlines of users and brands or items used by them. These outlines may not be useful only for this particular prediction task, but could also be used for other important tasks in e-commerce, such as client segmentation, product recommendation and client base growth for brands
Proportional Resonant Controlled Dual Active Bridge DC to AC Converter System with Enhanced Response
This paper deals with comparison of responses of PI and Proportional Resonant controlled DC to AC Converter systems. The objective of this work is to regulate the output of Dual Active Bridge DC to DC converter (DABDAC). The input DC is converted into high frequency AC using Half bridge inverter. It is stepped up by using step up transformer and then it is rectified. The DC is converted into Low frequency AC using a Half bridge inverter. The open loop DABDAC system, closed loop PI based DABDAC system an Proportional Resonant Controller (PRC)based DABDAC system are designed, modeled and simulated using MATLAB Simulink. The results of PR controlled system are compared with those of PI controlled system. The results indicate that the proposed PRC-DABDAC has better time domain response than PI controlled DABDAC system. The proposed DABDAC system has advantages like high gain and steady state error in output voltage.
Evaluation of Synchronization and MPPT algorithms in a DFIG Wind Turbine Controlled by an Indirect Matrix Converter
Most of generators utilized in wind turbines are the Doubly-Fed Induction Generator (DFIG). Indirect matrix converter (IMC) is a candidate for substituting the traditional back-to-back converter in the future due to advantages gained by elimination of electrolytic capacitor. Starting DFIG wind turbines and synchronizing to the grid is a challenge in practice because of large inrush currents that could damage switches. Synchronizing the DFIG wind turbine controlled by the IMC is presented in this paper. Also, maximum power point tracking algorithm performance of this configuration is examined. A laboratory scale prototype of the proposed configuration is built. Experimental results have confirmed effectiveness of this configuration
The Effect of Parameters Variation on Bilateral Controller
This paper analyzes the effects of the bilateral control parameters variation on the stability, the transparency and the accuracy, and on the operational force that is applied to DC motor and the master system. The bilateral controller is designed for rehabilitation process. PD controller is used to control the position tracking and a force gain controller is used to control the motor torque. DOB eliminate the internal disturbance and RTOB to estimate the joint torque without using sensors. The system consists of two manipulators, each manipulator has 1dof, master and slave teleoperation system, 4 control-architecture channel, DOB and reaction force observer. The master system is attached to human oberator. The slave system is attached to external load. The aim in this paper is to design the controller so that it requires less force to move the master manipulator and at the same time achieve high performance in position tracking
Direct Torque Control of Doubly Star Induction Motor Using Fuzzy Logic Speed Controller
This paper presents the simulation of the control of doubly star inductionmotor using Direct Torque Control (DTC) based on Proportional and Integralcontroller (PI) and Fuzzy Logic Controller (FLC). In addition, the workdescribes a model of doubly star induction motor in α-β reference frametheory and its computer simulation in MATLAB/SIMULINK®.The structureof the DTC has several advantages such as the short sampling time requiredby the TC schemes makes them suited to a very fast flux and torquecontrolled drives as well as the simplicity of the control algorithm.thegeneral- purpose induction drives in very wide range using DTC because it isthe excellent solution. The performances of the DTC with a PI controller andFLC are tested under differents speeds command values and load torque
Performance Analysis of ANN Model for Estimation of Trophic Status Index of Lakes
The health of water bodies across the globe is of high concern as the pollution is accelerating rigorously. With the interventions of simple technology, some significant changes could be bought up. Lakes are dying because of high Trophic Index Status which shows the eutrophication level of water bodies. Taking this into account, feed forward back propagation neural network model is used to estimate the Trophic Status Index (TSI) of lakes which could compute the value of TSI with the given parameters; pH, temperature, dissolved oxygen, Secchi disk transparency, chlorophyll and total phosphate. Two learning algorithms; Levenberg Marquardt (LM) and Broyden–Fletcher–Goldfarb–Shanno (BFGS) Quasi Newton were used to train the network, which belongs to different classes. The results were analyzed using mean square error function and further checked for the deviation from actual data. Among both the training algorithm; LM demonstrated better performance with 0.0007 average mean square error for best validation performance and BFGS Quasi Newton shows the average mean square error of 1.07
On-chip AMBA Bus Based Efficient Bridge between High Performance and Low Peripheral Devices
Today’s scenario of SOC deals with integrity and sharing of information or data with various level of communication. AMBA bus protocol has been proposed by ARM community to justify the uneven demand of integrity .In this paper functional description and implementation of high peripheral devices supporting protocol AXI2.0 and its interface between low peripheral devices has been proposed. The connection named as bridge take care of the protocol mismatch and operates on data transfer for uneven speed demand. Asynchronous FIFO has been considered to avoid the complex handshaking mechanism. The design has been implemented within VHDL and implemented on Xilinx Virtex 4