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H∞BASEDOBSERVER FOR DISTURBANCE COMPENSATION IN DECOUPLED TRMS USING LMI OPTIMIZATION
Get PDFTwin Rotor MIMO System is a laboratory model of helicopter. In this paper, the problem of disturbance rejection in TRMS is dealt with. Using disturbance observers, without any additional sensors is an attractive method to attenuate the effects of disturbances as they are highly cost effective. This method uses a simple form of DOBs, which does not need to solve the plant model inverse, and uses H∞control method using LMIs to design the Q-filter in the DOB. The estimation capability of DOB is verified using simulation results in frequency domain as well as in time domain
VIBRATION ANALYSIS OF A ROTATING TAPERED COMPOSITE BEAM WITH TIP MASS
Get PDFIn this study, free vibration responses of a rotating tapered composite beam with tip mass are investigated. The energy expressions for the kinetic and potential energies of a rotating composite beam with tip mass have been formulated. The energy expressions are then applied in Lagrange’s equations to develop the equation of motion of a composite beam with tip mass. The stiffness and mass matrices for a standard composite beam element with two end nodes with two degrees of freedom at each node are derived. Various parametric studies are performed to investigate the effect of tip mass and the rotational speed on the variation of natural frequencies of the composite beam. The investigations are also done to study the effect of hub radius on the natural frequencies. It is shown that the addition of tip mass increases the stiffness of the structure and consequently increases the natural frequencies
LOCATION AWARE CLUSTER BASED ROUTING IN WIRELESS SENSOR NETWORKS
Get PDFWireless sensor nodes are usually embedded in the physical environment and report sensed data to a central base station. Clustering is one of the most challenging issues in wireless sensor networks. This paper proposes a new cluster scheme for wireless sensor network by modified the K means clustering algorithm. Sensor nodes are deployed in a harsh environment and randomly scattered in the region of interest and are deployed in a flat architecture. The transmission of packet will reduce the network lifetime. Thus, clustering scheme is required to avoid network traffic and increase overall network lifetime. In order to cluster the sensor nodes that are deployed in the sensor network, the location information of each sensor node should be known. By knowing the location of the each sensor node in the wireless sensor network, clustering is formed based on the highest residual energy and minimum distance from the base station. Among the group of nodes, one node is elected as a cluster head using centroid method. The minimum distance between the cluster node’s and the centroid point is elected as a cluster head. Clustering of nodes can minimize the residual energy and maximize the network performance. This improves the overall network lifetime and reduces network traffic
VHDL IMPLEMENTATION OF GENETIC ALGORITHM FOR 2-BIT ADDER
Get PDFFuture planetary and deep space exploration demands that the space vehicles should have robust system architectures and be reconfigurable in unpredictable environment. The Evolutionary design of electronic circuits, or Evolvable hardware (EHW), is a discipline that allows the user to automatically obtain the desired circuit design. The circuit configuration is under control of Evolutionary algorithms. The most commonly used evolutionary algorithm is Genetic Algorithm. The paper discusses on Cartesian Genetic Programming for evolving gate level designs and proposes Evolvable unit for 2-bit adder based on Genetic Algorithm
A THREE-PHASE HIGH POWER FACTOR TWO-SWITCH BUCKTYPE CONVERTER
Get PDFThe paper proposes a three phase, two switch buck type converter with high power factor.The key feature of the proposed converter is that a switch in the converter has a lower peak voltage stress than a switch in a conventional threephase, single-switch buck-converter. A switch in the converter sees a line to neutral voltage across it rather than a line to line voltage which is the case for the switch in the conventional converter. The voltage stress in the proposed converter is limited to the peak value of the phase voltage of the input capacitors rather than the peak value of the line-to-line voltage, as is the case in the conventional converter. Since a switch in the proposed converter sees a line to neutral voltage instead of a line to line voltage the peak voltage stress is almost half than that of the switch in the conventional converter as this stress is reduced by a factor of sqrt(3). This reduces switching losses and allows lower rated standard devices to be used in converters. In the paper, the operation of the proposed converter is given and general considerations that should be taken into account when trying to design it are discussed. The feasibility of the converter is confirmed with results obtained from computer simulation and from an experimental prototype
EXPERIMENTAL VALIDATION AND DATA ACQUISITION FOR HYPER ELASTIC MATERIAL MODELS IN FINITE ELEMENT ANALYSIS
Get PDFThis paper presents the theory, experiment setups and solution implementation of Hyperelastic Material Models in Finite Element Analysis to provide the description of material behavior that matches the conditions the product sees in real life. This can be a complex matter because the real life scenario may have the product responding simultaneously to a multiplicity of conditions such as rate, temperature and the environment. Physical testing of elastomers for the purpose of fitting material models in finite element analysis requires experiments like uniaxial tension, biaxial tension, volumetric compression in multiple states of strain under carefully considered loading conditions
TESTING OF RIGID CELLULAR THERMAL INSULATION AS PER INDIAN STANDARDS
Get PDFThermal Insulations play a great role in keeping the flow of energy from hot to cold bodies to a minimum. Quality and effectiveness of thermal insulation is of prime importance and unless the properties of insulation are evaluated there is little chance of improvement of their performance. It is essential that properties of insulations be evaluated for acceptability according to national and international standards. In the present study, various tests were performed on Rigid cellular insulation (Thermocol) as per IS 11239 to determine the temperature at which the insulation get distorted as well as to study its characteristics when the insulation get ignited in vertical as well as horizontal positions. The statistical analysis of experimental results was carried out at 95 % confidence level for all the tests and the % error in various parameters was found to be within ± 1 to 3%. The findings of the present study may be helpful to the researchers, manufacturers and industries dealing with the similar insulating materials
COMPARISON OF CONVENTIONAL DRAWING, INVERTED DRAWING AND WARM FORMING PROCESSES FOR DEEP DRAWING OF ALUMINIUM CUPS
Get PDFCup drawing is one of the important operations in sheet metal forming. Manufacturing of the aluminium base cup involves several stages such as blanking, first drawing, second drawing, taper formation and trimming. This increases the process time. An attempt has therefore, been made to develop a comprehensive, rigorous, yet easily-workable method of analysis for designing a die set to combine the intermediate stages of drawing process. Conventional drawing, inverted drawing and warm forming processes are experimented for yielding successful drawing in single setup. Die sets are separately designed for above said processes. The die sets, thus designed is simulated using DEFORM-F2 to analyze the successful Drawability of the die sets. From the simulations conducted, the die set designed for warm forming process yields greater Limiting Draw Ratio (LDR). Using warm forming process, the LDR of 2.0 was achieved which is much higher when compared with the conventional drawing
AN EFFICIENT AND SYSTEMATIC VIRUS DETECTION PROCESSOR FOR EMBEDDED NETWORK SECURITY
Get PDFNetwork security has always been an important issue and its application is ready to perform powerful pattern matching to protect against virus attacks, spam and Trojan horses. However, attacks such as spam, spyware, worms, viruses, and phishing target the application layer rather than the network layer. Therefore, traditional firewalls no longer provide enough protection. However, the solutions in the literature for firewalls are not scalable, and they do not address the difficulty of an antivirus. The goal is to provide a systematic virus detection hardware solution for network security for embedded systems. Instead of placing entire matching patterns on a chip, our solution is based on an antivirus processor that works as much of the filtering information as possible onto a chip. The infrequently accessing off-chip data to make the matching mechanism scalable to large pattern sets. In the first stage, the filtering engine can filter out more than 93.1% of data as safe, using a merged shift table. Only 6.9% or less of potentially unsafe data must be precisely checked in the second stage by the exact-matching engine from off-chip memory. To reduce the memory gap and to improve the performance, we also propose three algorithms are used: 1) a skipping algorithm; 2) a cache method; and 3) a prefetching mechanism
TEXT CLUSTERING IN CONCEPT BASED MINING
Get PDFIn text mining most techniques depends on statistical analysis of terms. Statistical analysis trances important terms within document only. However this concept based mining model analyses terms in sentence, document and corpus level. This mining model consist of sentence based concept analysis, document based and corpus based concept analysis and concept based similarity measure. Experimental result enhances text clustering quality by using sentence, document, corpus and combined approach of concept analysis