Volume 3 - Issue 11

Design of Low Voltage and High Speed Double-Tail Dynamic Comparator for Low Power Applications
K. Sumalatha, Mr. B. Prathap reddy

Abstract: Comparators are basic building elements for designing modern analog and mixed signal systems. Speed and resolution are two important factors which are required for high speed applications. This paper presents a design for an on chip high-speed dynamic latched comparator for high frequency signal digitization. The dynamic latched comparator consists of two cross coupled inverters comprising a total of 9 MOS transistors. The measured and simulation results show that the dynamic latched comparator design has higher speed, low power dissipation and occupying less active area compared to double tail latched and preamplifier based clocked comparators. A new fully dynamic latched comparator which shows lower offset voltage and higher load drivability than the conventional dynamic latched comparators has been designed. With two additional inverters inserted between the input-stage and output-stage of the conventional double-tail dynamic comparator, the gain preceding the regenerative latch stage was improved and the complementary version of the output-latch stage, which has bigger output drive current capability at the same area, was implemented.
Keyword And Phrases: Comparator, Double-Tail Comparator

Security Enhancement of Image Encryption Based on Matrix Approach using Elliptic Curve
F. Amounas, E.H. El Kinani

Abstract: Encryption is used to securely transmit data in open networks. Each type of data has its own features. With the rapid growth of internet, security of digital images has become more and more important. Therefore different techniques should be used to protect confidential image data from unauthorized access. In this paper an encryption technique based on elliptic curves for securing images to transmit over public channels will be proposed. Encryption and decryption process are given in details with an example. The comparative study of the proposed scheme and the existing scheme is made. Our proposed algorithm is aimed at better encryption of all types of images even ones with uniform background and makes the image encryption scheme more secure. The output encrypted images reveal that the proposed method is robust.
Keywords: Image Encryption, Elliptic Curve Cryptography, Involutory Matrix, Elliptic Curve Discrete Logarithm Problem, Mapping technique.

Applications of Factorial Function n=1 in determination of Specific Reaction Rate and Half Life Period
Anshaj Ronghe

Abstract: In this research paper, specific reaction rates of first order, second order; third order and m th order reactions are represented in terms of factorial function. These results would be further applied to obtain half life period as a particular case in application section.
Keywords: Factorial function, Order of reaction, Specific Reaction Rate (or velocity constant or rate constant), half life period.

Fingerprint Based Biometric ATM Authentication System
Dhiraj Sunehra

Abstract: Biometrics technology is rapidly progressing and offers attractive opportunities. In recent years, biometric authentication has grown in popularity as a means of personal identification in ATM authentication systems. The prominent biometric methods that may be used for authentication include fingerprint, palmprint, handprint, face recognition, speech recognition, dental and eye biometrics. In this paper, a microcontroller based prototype of ATM cashbox access system using fingerprint sensor module is implemented. An 8-bit PIC16F877A microcontroller developed by Microchip Technology is used in the system. The necessary software is written in Embedded 'C' and the system is tested.
Keywords: Automatic Teller Machine, PIC16 microcontroller, Finger print recognition, Liquid Crystal Display.

The unsuitability of the application of Pythagorean Theorem of Exhaustion Method, in finding the actual length of the circumference of the circle and Pi
R. D. Sarva Jagannadha Reddy

Abstract: There is only one geometrical method called Exhaustion Method to find out the length of the circumference of a circle. In this method, a regular polygon of known number and value of sides is inscribed, doubled many times until the inscribed polygon exhausts the space between the polygon and circle as limit. In the present paper, it is made clear, that the value for circumference, i.e. 3.14159265358…. of polygon, attributing to circle is a lower value than the real value, and the real value is 14 24 = 3.14644660942 adopting error-free method.
Keywords: Circle, corner length, diameter, diagonal, polygon, side, square.

ANTENNAS
K. V. S. Sreedhar

Abstract: To explain the design of antenna both in software and hardware

An Improved Quantum-behaved Particle Swarm Optimization Algorithm Based on Chaos Theory Exerting to Particle Position
Pan Dazhi, He Min, Chen Youjun, Yang Shuang

Abstract: In this paper, we propose an improved quantum-behaved particle swarm optimization (QPSO), introducing chaos theory into QPSO and exerting logistic map to every particle position X(t) at a certain probability. In this improved QPSO, the logistic map is used to generate a set of chaotic offsets and produce multiple positions around X(t). According to their fitness, the particle's position is updated. In order to further enhance the diversity of particles, mutation operation is introduced into and acts on one dimension of the particle's position. What's more, the chaos and mutation probabilities are carefully selected. Through several typical function experiments, its result shows that the convergence accuracy of the improved QPSO is better than those of QPSO, so it is feasible and effective to introduce chaos theory and mutation operation into QPSO.
Keywords: Particle swarm optimization, Quantum-behaved particle swarm optimization, Chaos theory, Logistic Map, Mutation operation comma.

A Systematic Review of Congestion Control in Ad Hoc Network
M. Rajesh, Dr. J. M. Gnanasekar

Abstract: Congestion is said to occur in the network when the resource demands exceed the capacity and packets are lost due to too much queuing in the network. During congestion, the network throughput may drop to zero and the path delay may become very high. A congestion control scheme helps the network to recover from the congestion state. In fact, security plays a vital role in Wireless Ad hoc network. This paper presents a systematic literature review to provide comprehensive and unbiased information about various current model Congestion Control conceptions, proposals, problems and solutions in Ad hoc for safety transportation. For this purpose, a total of 33 articles related to the security model in Congestion Control published between 2008 and 2013 were extracted from the most relevant scientific sources (IEEE Computer Society, ACM Digital Library, Springer Link and Science Direct). However, 18 articles were eventually analyzed due to several reasons such as relevancy and comprehensiveness of discussion presented in the articles. Using the systematic method of review, this paper succeeds to reveal the main security threats and Error control, challenges for security, security requirement in Congestion Control in Wireless Ad hoc network (CCWAN) and future research within this scope.
Keyword: Congestion control, Security, Error control, CCWAN, Systematic Literature Review.