Showing papers by "MKSSS's Cummins College of Engineering for Women published in 2011"

Investigation of the Leggett-Garg inequality for precessing nuclear spins.

Abstract: We report experimental implementation of a protocol for testing the Leggett-Garg inequality (LGI) for nuclear spins precessing in an external magnetic field. The implementation involves certain controlled operations, performed in parallel on pairs of spin-$1/2$ nuclei (target and probe) from molecules of a nuclear magnetic resonance ensemble, which enable evaluation of temporal correlations from an LG string. Our experiment demonstrates violation of the LGI for time intervals between successive measurements, over which the effects of relaxation on the quantum state of target spin are negligible. Further, it is observed that the temporal correlations decay, and the same target spin appears to display macrorealistic behavior consistent with LGI.

A combinational logic implementation of S-box of AES

Abstract: This paper presents a combinational logic based Rijndael S-box implementation for the SubByte transformation on ASIC. Combinational implementation of S-box results in low cost, small area occupancy and high throughput as compared to the typical ROM based lookup table implementation with fixed and unbreakable access time. S-box has been implemented using 0.18µm CMOS standard cell library at 1.62V and runs at clock frequency of 71.43MHz. We could achieve throughput of 571.5Mbps with core utilization of 85%, core area occupied is 39.88.4µm2 using only 178 cells. Total power dissipation of the S-box implementation is 0.611mW which is quite lower than other literature available.

Media Access Control protocol modelling for Mobile Sensor Network-using OMNeT++ -MiXiM network simulator

Abstract: Wireless Sensor Network (WSN) consist of large number of battery operated sensing and computing devices deployed randomly for monitoring applications. With the advent of new technologies WSNs are providing a new class of information to human beings. In most cases the networks were stationary but as a evolutionary step the WSNs have to consider mobility. This new class of sensor networks is Mobile Wireless Sensor Networks. Eg moving robots, surveillance aircrafts. Nodes share a single channel for communication. To share communication channel, establishment of a MAC protocol is required in the sensor nodes. The objective of the MAC protocol is to regulate access of the shared wireless medium, so that the performance requirements of the underlying application are satisfied. Energy efficiency and Mobility are big challenges for Medium Access Control protocol design to give a reliable communication. Paper describes a Mobility aware MAC protocol, implemented using OMNeT++ network simulator. OMNeT++ is open source discrete event simulator. Mixim is 'mixed simulator', developed for wireless and mobile simulations in OMNeT++.

Synthesis, characterization and evaluation of reflectivity of nanosized CaTiO3/epoxy resin composites in microwave bands

Abstract: Microwave absorbing materials play a major role in electromagnetic interference and compatibility measurements in anechoic chambers. Nanocrystalline calcium titanate (CT) was synthesized by hydrothermal method and further composites of CT/epoxy resin were fabricated as thin solid slabs of four different weight ratios. The composite material was analyzed by X-ray diffraction (XRD) and transmission electron microscopy (TEM), which reveals that CT was observed to be in the monoclinic phase with an average crystallite size of 24 nm. The reflectivity measurement of the composite materials was carried out by the transmission/reflection method using a vector network analyzer R&S: ZVA40, in the X- and Ku-bands. The effective permittivity and permeability of the samples was also computed with the help of measured transmission and reflection coefficients. The results show that CT with equal weight of epoxy resin provides −30 dB at 8.5 GHz in the X-band and −19.5 dB at 18.0 GHz in the Ku-band. Reflectivity was found to be better than −10 dB for 2.2 GHz and 1.9 GHz for X-band and Ku-band, respectively and encourages use of it as potential microwave absorber material.

Enhancement of Noisy Speech Signals for Hearing Aids

Abstract: it is very difficult to understand speech signals in presence of background noise for the normal listeners and hearing impaired persons. The human speech and hearing organ is inherently sensitive to interfering noise. Interfering noise decreases speech intelligibility and quality which makes speech communication troublesome and causing human mistakes. Speech signals from the uncontrolled environments may contain degradation components along with the required speech components. Speech enhancement algorithms removes or reduces the noise and improve one or more perceptual aspects of noisy speech most notably quality and intelligibility. This paper reports a performance evaluation of Spectral subtraction algorithm and its modified versions for Hearing aids in different environments such as restaurant, train and Car environments. Clean speech signals are corrupted by background noise respectively multi-talker babble noise, train noise, and car engine noise at four different signal-to-noise ratio levels-2dB, 0dB, 5dB, 10dB. Subjective and objective type evaluation of enhanced speech signals were carried out. The evaluation of intelligibility and quality of enhanced speech is reported for hearing Aids. Section I introduction, section II explains basic block diagram of speech enhancement, explains basic Spectral subtraction speech enhancement algorithm in detail and its various modified versions of spectral subtraction algorithm, section III explains performance evaluation of this speech enhancement algorithms in terms of quality and intelligibility for Hearing aid, section-IV conclusion.

An enhanced Intrusion Detection System using Adaptive Acknowledgment based algorithm

Abstract: The Mobile Ad Hoc Network (MANET) consists of a collection of wireless mobile nodes. These Mobile nodes are connected by wireless link. This network do not required any infrastructure or centralized access point such as base station. MANETS are highly venerable for Passive and Active Attacks because of their open medium, rapidly changing topology and lack of centralized monitoring. To protect the MANET from Active attack such as Black Hole Attack we are considering enhancement i n Intrusion Detection System. Most of the current Intrusion Detection Systems (IDSs) for MANETS rely on the watchdog technique. To overcome the disadvantages of watchdog we propose a novel mechanism as “Adaptive Acknowledgment (AACK)” This mechanism is an enhancement to the TWOACK scheme where its detection overhead is reduce while the detection efficiency get increased. NS2 is used to simulate and evaluate the proposed scheme.

Performance of WiMAX/ IEEE 802.16 with Different Modulation and Coding

Abstract: WiMAX (Worldwide Interoperability for Microwave Access) is the IEEE 802.16 Standards based wireless technology that provides MAN (Metropolitan Area Network) broadband and IP connectivity. WiMAX is promising technology which offers high speed voice, video and data services based on OFDM. It offers both line of sight and non line of sight wireless communication. In this paper performance of WiMAX with different modulation (BPSK, QPSK and QAM) and coding is studied on the basis of Bit Error Rate, Signal to Noise Ratio and error probability.

A review on steer-by-wire system using Flexray

Abstract: Flexray is inclusive solution to managing communication between multiple ECUs (Electronic Control Units) in the vehicles. The Flexray protocol specifies versatile message identifiers that can be mapped to specific control information categories. Communications may occur at a maximum recommended rate of 10 Mbit/sec. FlexRay is a next-generation automotive control and communication protocol projected for safety-critical automotive applications such as X-by-Wire system, where electronic connections will replace the mechanical linkages. In this paper, we have presented a review, how the Flexray is expanding its area of working and applications in automotive Electronics.

Design and development of 4 element linear microstrip patch antenna array with null steering by phase control

Abstract: The paper presents design and development of a linear microstrip patch antenna array and also, a method to change the radiation pattern of the array by steering null in the desired direction. This is achieved by changing the phase of each of the array element which produces a null in the radiation pattern without significantly affecting the main beam lobe. Different methods can be used for array synthesis. In this paper the Schelkunoff polynomial method is used for the synthesis of array. For an N element array, (N-I) nulls can be formed. The array is designed around a frequency of 930 MHz using four microstrip patch antenna elements of rectangular shape arranged in linear configuration. The theoretical design of the antenna array is presented initially and then the results of the array simulation and the hardware implementation are presented.

Fundamenatals of active noise control for local cancellation of noise

Abstract: This project is applicable for attenuating external noise inside a car, office cubical partition and making the environment noise free. It can also be used in the development of a noise cancellation headphone. In this project a noise free environment for a room is developed and cancellation of active noise is achieved using hardware and software techniques. Real time Active Noise Cancellation can be achieved through DSP TMS 320C6713 processor and anti phase signal is generated for noise cancellation. The noise signal is given as input to processor and residual noise is used to update the coefficient of FIR filter through feedback. Acoustic impulse response between input noise and anti phase output is optimized to reduce the error.

Direct reading flame photometer using digital photography and image processing

Abstract: The work presents a new technique for the detection of percentage of electrolytes in a flame using digital photography and image processing. Various samples containing different concentrations of alkali metals like sodium and potassium are prepared and aspired in a flame photometer. The flame images are captured using a consumer grade digital camera of known resolution. The images for various concentrations are captured. By developing image processing algorithm the change in the flame colour is identified. Correlation between the colour and the concentration is developed using various analytical techniques. The results indicate that the image-based measurements agree with the corresponding known values within an error range of about ±5%.

Equation for Predicting Shelf Life of an Apple

Abstract: The shelf-life of a Fruit is critical in determining both its quality and profitability. Everyone benefits from healthy produce. Approximately Rs.105Crores {$200million} is lost each year in India due to waste caused by post harvest diseases, poor temperature management, bruising and other factors. Shelf life is nothing but date of minimum durability. An apple is not dead at the time of harvest. It remains a living, respir¬ing organism and continues to take in oxygen and give off carbon dioxide and another gas, ethylene. Since the apple is no longer receiving nutrients from the tree but is still respiring, it must use up the food it has stored over the growing season. The low temperature, high humidity, and exchange of gases through air circulation serve to slow those natural events as much as possible. A mathematical relationship has been established for predicting the shelf life of an apple. Our study quantitatively takes in to account parameters such as firmness, colour of apple, atmospheric temperature, and respiration rate. This fundamental equation could be potentially used by farmers, food malls, and big food chains. This relationship can be extended to predict shelf life of perishable fruits.

A novel subcarrier-power assignment scheme for OFDMA systems

Abstract: This is subcarrier-power assignment scheme for various types of frequency-division multiple access (FDMA) systems such as SC-FDMA and OFDMA. Scheme is designed for uplink as well as downlink. This scheme has two parts, subcarrier assignment and power assignment. The subcarrier assignment is called as worst subcarrier avoiding (WSA) algorithm which is capable of avoiding allocating users the subcarriers with low channel qualities due to severe fading. WSA is low-complexity algorithm. The power-assignment is based on channel-inversion. Studies show that the attainable error performance of the FDMA systems used the WSA algorithm is the identical, irrespective of the multiplexing scheme used. Our simulation result shows that, bit error rate has reduced after implementing this scheme.