Showing papers by "KCG College of Technology published in 2014"

Comparison of Longley-Rice, ITU-R P.1546 and Hata-Davidson propagation models for DVB-T coverage prediction

Abstract: This paper compares precision field-strength measurements taken by a Rohde & Schwarz FSH-3 portable spectrum analyzer with simulation results derived from the ITM coverage prediction model (Irregular Terrain Model), also known as NTIA-ITS Longley-Rice model, in conjunction with the 3-arc-second SRTM (Satellite Radar Topography Mission) geographical data, the propagation predictions of ITU-R Recommendation P.1546 and those of the empirical Hata-Davidson model using HAAT. ITU-R P.1546 and Hata-Davidson models exhibit higher errors at longer distances and therefore necessary corrections should be introduced in the models in order to increase propagation prediction accuracy. Especially, measurements results show that ITU-R P.1546, on average, underestimates the field strength at distances longer than 50 km. The Longley-Rice model using the terrain digital elevations is more accurate, as expected, and its results are closer to the measurement data.

Chaotic dynamics of a zero average dynamics controlled DC-DC Cuk converter

Abstract: The undesirable subharmonics in periodically driven non-linear systems such as switching power converters is a more common problem in power electronic circuits. Such operations are usually avoided by modifying the circuit parameters which necessitates a proper understanding of the system. In the present study, non-linear dynamic behaviour in a zero average dynamics (ZAD) controlled DC–DC Cuk converter is investigated. The effects of varying the control parameters on the qualitative behaviour of the system are studied in detail. Bifurcation analysis of a ZAD controlled DC–DC Cuk converter has not been reported so far in the literature as it involves complex modelling and implementation of the overall control system. To reduce the complexity in deriving the map dynamics and computing the ZAD control parameters, a reduced order model is derived. Moment matching technique is used to obtain the reduced order model. It is found that for even small control parameter variations, the system exhibits period-doubling bifurcation. The dynamics of this converter system has been mathematically described and analysed with a simple discrete map. Computer simulations as well as experimental investigations are performed to study the qualitative behaviour of the system under variations of different parameters. The results offer useful information of parameter space for the design and operation of the converter in the desired fundamental stable regime. Finally, a time-delay component is included in the ZAD control strategy and it is shown that the onset of chaos can be delayed.

Non-linear intermittent instabilities and their control in an interleaved DC/DC converter

Abstract: The undesirable intermittent instabilities in periodically driven parallel power converter are caused due to periodic interferences in input voltage This is a more common problem in power electronic circuit design and such operations are usually avoided by controlling the circuit parameters In this study, the mechanism and conditions for the emergence of intermittent instabilities and remerging chaotic band attractors (or Feigenbaum sequences) in a master-slave controlled parallel buck converter are investigated It is found that sinusoidal-type interference in input voltage at frequencies near the switching frequency or its rational multiples of this circuit results typically in period-bubbling, chaos and intermittency It is also shown that an optimal, phase-shifted sinusoidal interference added to the reference voltage controls the period-bubbling behaviour and significantly extends the parameter range of desirable period-1 operation The dynamics of this converter has been first investigated with suitable numerical simulations The ordered and the chaotic dynamics of this system have been further mathematically described and analysed with a simple discrete map and experimental means Experimental observations are found to be in good agreement with the analytical and simulation results

Design of Synthetic Optimizing Neuro Fuzzy Temperature Controller for Twin Screw Profile Plastic Extruder Using Labview

Abstract: Controlling the temperature of the twin screw extruder is non linear and suffers from problems related to undesirable overshoot, longer settling time, coupling effects and disturbances. The system is designed with four different control techniques to control temperature at different set point changes and as well as to control sudden input disturbances. The technique involved is conventional PID controller, neural controller, mamdani type fuzzy Logic Controller and the proposed method is neuro fuzzy controller. The proposed method is smoothing of undesired control signal and maintains the temperature exactly at its set points. The software incorporates LabVIEW graphical programming for twin screw plastic extruder toolbox.

Efficient hardware implementation of scalable FFT using configurable Radix-4/2

Abstract: This paper demonstrates the FPGA implementation of FFT algorithm that is precisely designed to induce an efficient implementation of the parameters involving area and performance by configuring the size of FFT input points which is well suited for wireless and signal processing applications. An optimized architecture is demonstrated in this paper for computing FFT of length 8/16/32/64/128/512 and 1024 using Radix-4/Radix 2∗2 FFT in FPGA and is compared with Xilinx LogiCore™ FFT IP with configurable point size. It is found that proposed design is more efficient and effective in terms of area and performance while achieving the input system configurability. A novel Address Generator architecture has been proposed which facilitates for Complex Math Processor (CMP). This single generator helps in effectively carrying out the address mapping scheme. The occurrence of hardware overheads is minimized by using the multiplexor for complex arithmetic's. The entire RTL design is described using Verilog HDL and simulated using Xilinx ISim. This experimental result is tested on Spartan-6 XC6SLX4, which is the smallest device on Spartan 6 family and found that Xilinx FFT IP core over maps the available DSP48 slices. The result shows 538 LUT's, 847 Flip Flops, 3 DSP Slices, Maximum Frequency of 217 MHz. This is about 60% improvement in resource usage and 14% upgrade in the performance thus creating a low cost Configurable FFT Processor.

An improved Pearson's correlation proximity-based hierarchical clustering for mining biological association between genes.

Abstract: Microarray gene expression datasets has concerned great awareness among molecular biologist, statisticians, and computer scientists. Data mining that extracts the hidden and usual information from datasets fails to identify the most significant biological associations between genes. A search made with heuristic for standard biological process measures only the gene expression level, threshold, and response time. Heuristic search identifies and mines the best biological solution, but the association process was not efficiently addressed. To monitor higher rate of expression levels between genes, a hierarchical clustering model was proposed, where the biological association between genes is measured simultaneously using proximity measure of improved Pearson's correlation (PCPHC). Additionally, the Seed Augment algorithm adopts average linkage methods on rows and columns in order to expand a seed PCPHC model into a maximal global PCPHC (GL-PCPHC) model and to identify association between the clusters. Moreover, a GL-PCPHC applies pattern growing method to mine the PCPHC patterns. Compared to existing gene expression analysis, the PCPHC model achieves better performance. Experimental evaluations are conducted for GL-PCPHC model with standard benchmark gene expression datasets extracted from UCI repository and GenBank database in terms of execution time, size of pattern, significance level, biological association efficiency, and pattern quality.

Order preserving contact transformations and dynamical symmetries of scalar and coupled Riccati and Abel chains

Abstract: We identify contact transformations which linearize the given equations in the Riccati and Abel chains of nonlinear scalar and coupled ordinary differential equations to the same order. The identified contact transformations are not of Cole-Hopf type and are \emph {new} to the literature. The linearization of Abel chain of equations is also demonstrated explicitly for the first time. The contact transformations can be utilized to derive dynamical symmetries of the associated nonlinear ODEs. The wider applicability of identifying this type of contact transformations and the method of deriving dynamical symmetries by using them is illustrated through two dimensional generalizations of the Riccati and Abel chains as well.

Laser performance of rhodamine B and methyl violet B base dye mixture in solid and liquid media

Abstract: The performance of a distributed feedback dye laser (DFDL) by employing methyl methacrylate (MMA) co-doped with rhodamine B and methyl violet B base dyes was investigated. The dye mixture was incorporated into a solid polymeric matrix and then in a liquid medium and a laser pulse was pumped into it using a 532 nm Nd:YAG laser. Characteristics of energy transfer DFDL and its output powers on various pump powers and acceptor concentration were evaluated both theoretically and experimentally. Slope efficiency of the dye laser as well as wavelength tunability in both liquid and solid media was studied.

Design and Development of XY Micro-Positioning Stage Using Modified Topology Optimization Technique

Abstract: XY positioning stages are fundamental components during precision manipulation of micro sized objects. A compliant mechanism based mechanism is the appropriate choice for the design of XY stage. Topology optimization techniques are utilized to design the compliant mechanism. During the process of topology optimization, senseless regions are appearing from the manufacturability perspective. Senseless regions are staircase boundaries and node to node connectivity which is impossible to manufacture. Interpolation function is included in the topology optimization to minimize the effect of senseless regions. However topologically developed design is post processed to attain the manufacturability. Structural performance of the post processed final design is validated through Finite Element Method (FEM) and experimental technique.

Radix-2 h online floating point multipliers

Abstract: Digital signal processing hardware uses digit serial arithmetic when latency can be traded off for higher clock speeds, resource and input-output utilization. Floating-point representations are important when dealing with very large data sets or sets where data range may be unpredictable as these representations may have a larger dynamic range. Field Programmable Gate Array architectures make them suitable as hardware accelerators for implementing high performance floating-point computations. In this paper, a number of improved designs for Radix-2h online floating-point multiplication are presented, analysed and compared on the basis of latency, throughput, cycle time and resource utilization. The architecture of a novel online floating-point multiplier using an interleaved number representation that results in an increased throughput and has the advantage of carrying out normalization for overflow with reduction in cycle time, resource utilization and latency is also presented.

Master Cluster Head and Vice Cluster Head Algorithm for Wireless Sensor Networks Using PSO

Abstract: One of the most significant strategy measures of wireless sensor networks (WSNs) is energy efficiency Grouping affords an effective way for encompassing the lifetime of the network We offer a double cluster-heading clustering algorithm using particle swarm optimization (PSO-DH) The algorithm computes two cluster skulls The determination of the dominant cluster and the immorality cluster-head needs consider the state information, including position and energy reservation about nodes and their neighbors Because every node contains a list of information about his neighbors and location using connected dominating set The dominant cluster head (DCH) receives and masses data to analyst directly The algorithm poises the energy consumption, so it can encompass the network life time effectively

Efficient Hardware Implementation of 1024 Point Radix-4 FFT

Abstract: Since FFT algorithm is extremely demanding task and has several applications in the areas of signal processing and communication systems, it must be precisely designed to induce an efficient implementation of the parameters involving area and performance. To fulfill this requirement an optimized architecture is demonstrated in this paper for computing 1024-point, Radix-4 FFT using FPGA and is majorly compared with Xilinx LogiCoreTM FFT IP and found that proposed design is more efficient and effective in terms of area and performance. A novel architecture referred to as 2-D Vector Rotation and Complex Math Processor has been proposed in this paper. This single structure rotation helps in effectively carrying out the complex multiplications. The algorithm implements multiplexor hardware for computing the complex multipliers, thus consuming the minimal hardware resources. The entire RTL design is described using Verilog HDL and simulated using Xilinx ISim[TM]. This experimental result is tested on Spartan-6 XC6SLX150T. The result shows 557 LUT’s, 837 Flip Flops, 3 DSP Slices, Maximum Frequency of 215 MHz. This is about 52% improvement in resource usage and 5% upgrade in the performance.

Frequent Itemsets Generation using Efficient Utility Mining Algorithm

Abstract: Utility-based data mining is a rapidly developing research area in all types of utility factors in data mining processes. High utility mining is an emerging domain in Utility based data mining which is aimed at finding only itemsets that possess high utility value. Many algorithms are aiming at finding high utility itemsets. A well-known algorithm called Improved Fast Utility Mining (iFUM) lacks in functional accuracy when applied to large volumes of database. Hence, an Efficient Utility Mining (EUM) algorithm proposed in this paper to find all utility itemsets within the given utility threshold and timestamp. Moreover, a novel method is proposed in this paper for generating different types of utility frequent itemsets such as High Utility High Frequency (HUHF), High Utility Low Frequency (HULF), Low Utility High Frequency (LUHF), Low Utility Low Frequency (LULF) using a combination of Efficient Utility Mining (EUM) algorithm and Frequent Itemset Mining (FIM) algorithm for a given time interval.

Ranking model adaptation for domain specific mining using binary classifier for sponsored ads

Abstract: Domain — specific search focuses on one area of knowledge. Applying broad based ranking algorithms to vertical search domains is not desirable. The broad based ranking model builds upon the data from multiple domains existing on the web. Vertical search engines attempt to use a focused crawler that index only relevant web pages to a predefined topic. With Ranking Adaptation Model, one can adapt an existing ranking model of a unique new domain. The binary classifiers classify the members of a given set of objects into two groups on the basis of whether they have some property or not. If it is property of relevancy, it is returned to the search query of that particular domain vertical. Sponsored ads are then placed alongside the organic search results and they are ranked with the help of bid, budget and quality score. The ad with the highest bid is placed first in the ad listings. Later, the ad with a maximum quality score is found by click through logs which is replaced in first position. Thus, both organic search and sponsored ads are returned for the specific domain, making it easy for the users to get access to real time ads and connect directly with advertisers as well as to get information on the search query.