UET Peshawar Publications Site (University of Engineering and Technology, Peshawar)
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ROW LEVEL IMAGE FORGERY DETECTION TECHNIQUE USING EMBEDDED DIGITAL SIGNATURES
No full textImage forgery detection is one of the most important issues in today’s modern world. It has become very easy to change the contents of digital images with image editing tools and software. This paper is presenting a new technique to detect any changes made in digital images. This technique ensures the integrity of digital image at row level and using embedded digital signatures. Using message digest 5 algorithm, digital signature is generated from selected pixels of each row using selected pixels for and embedded in the least significant bits of selected pixel of corresponding row of digital image. The proposed technique is powerful enough to detect different image manipulations. The results show that it can successfully detect one least significant bit alteration made in any pixel of digital image
BENEFICIATION STUDIES OF MALAKAND LOW GRADE GRAPHITE ORE FOR INDUSTRIAL USE
No full textGraphite due to its wide variety of industrial applications has been used since old ages. In Malakand area graphite occurs in association with impurities such as quartz, calcite, mica, apatite, pyrite etc. In order to obtain high grade marketable graphite removal of these impurities is necessary, The present study has been undertaken to upgrade the Malakand low grade and make it suitable for industrial use. Flotation technique was applied for beneficiation studies using locally available reagents. Detailed flotation tests were carried out to investigate the effects of flotation parameters on grade and recovery of graphite, these included particle size, type of collector, conditioning time, impeller speed, pulp density and flotation time. Carbon content of 14% in the graphite feed has been enhanced to 80% in the final concentrate product
A REVIEW OF FEATURE SELECTION TECHNIQUES IN STRUCTURE LEARNING
No full textIn the last two decades, there has been significant advancement in heuristics for inducing Bayesian belief networks for the purpose of automatic distillation of knowledge from masses of data with target concepts.However, there are various circumstances where we are confronted to fix a set of most influencing variables in modelling of class variable. This arises in provision of confidence measures on set of variables used in the structure learning of data. In this study, we have tweaked empirical as well as theoretical aspects of various feature selection evaluators, their corresponding searching methods under six well known scoring functions in K2 which is a notable structure learning technique in Bayesian belief network. We have come up with some useful findings for overall computationally efficient approach among eleven evaluators. This analysis is useful in inducing better structure from the given dataset in imparting improved performance metric for Bayesian belief network
EVALUATING PERFORMANCE OF DIFFERENT ROUTING PROTOCOLS IN MANET ENVIRONMENT BASED ON TCP WINDOW SIZE EVALUATION
No full textMobile Adhoc Networks (MANET) refers to an arrangement of wireless mobile nodes that have the tendency of dynamically and freely self-organizing into temporary and arbitrary network topologies. Performance of the MANETs primarily depends upon the protocol running at the backend for routing the packets between the mobile nodes of the network. Each of these protocols has its own pros and cons in different scenarios. In this paper we have simulated an environment of MANETs consisting of a few Mobile nodes that tend to form a network amongst eachother during their random mobile behaviour. The environment has been simulated using three different routing protocols via the Network Simulator(NS)-2.35 scripting and the performance of these protocols have been compared based upon their TCP window size evaluation and the number of tcp packets successfully received at the receiving node under each scenario
IMPLEMENTATION AND EXPERIMENTAL ANALYSIS OF CONVENTIONAL PID CONTROLLERS FOR EFFICIENT HEAT TREATMENT OF FRUIT JUICES IN PLATE HEAT EXCHANGER
No full textSteady-state and dynamic analysis of plate heat exchangers has always remained the major concern for process control in food industry. Dairy products like milk and fruit juices are treated in plate heat exchanger for pasteurization but the introduction of many inherent and uneven disturbances by the process yields both product and energy losses. The current work is aimed on the development and implementation of conventional Proportional-Integral-Derivative (PID) control algorithm in order to control the temperature of a fruit juice at the exit of a plate heat exchanger. Plate heat exchanger is used to raise the temperature of the once-through continuous flow of a fruit juice or process cold fluid up to a fixed temperature with the recycled hot water. Various types of fruit juices were processed for that purpose. The controller was tuned using the recommendations of Ziegler and Nichols (Z-N) and Cohen and Coon (C-C). The plant was logged through PID virtual controller software. The influence of load variables and set point tracking was evaluated under the Z-N and C-C controller settings and was experimentally tested for various dairy fluids. It is shown that better throughput up to 77 % recovery of product has been achieved with Z-N controller settings but at the expense of more energy consumption as compared to C-C controller settings
DYNAMIC MODELING AND CONTROLLER DESIGN FOR NUCLEAR POWER PLANT
No full textHigher order mathematical modeling and discrete fast output sampling control synthesis for PHWR (Pressurized Heavy Water Reactor)-type nuclear power plant is presented in this paper. The nonlinear dynamic model of PHWR power reactor is developed based on reactor, logarithmic amplifier, moderator level control valve and reactivity system. The nonlinear model is characterized by 15 state variables and one input. This higher order nonlinear model is linearized at full power operating point. A standard higher order state space model is realized for controller design purpose. An advanced discrete controller is synthesized for state space model of PHWR using fast output sampling methodology. Noise sensitivity is a typical problem with this type of controller. In this research work, a small deviation is allowed in order to reduce the noise sensitivity. Theproblems of noise sensitivity and poor output error dynamics are addressed and a multi-objective optimization problem is solved using LMI (Linear Matrix Inequalities) formulation. Fast output feedback gains are computed using LMI tool for MATLAB. An advanced fast output sampling controller is evaluated for power maneuvering from 270 MWth to 310 MWth on the nuclear power plant in Pakistan and found highly efficient and satisfactory within the control design constraints
A Novel Wideband Microstrip Patch Antenna for Satellite Communications in Ku-Band
No full textIn this paper bandwidth enhanced microstrip patch antenna has been proposed for satellite communications. The bandwidth has been increased using parasitic patches. The size of the proposed antenna is 15x8 mm2. It has been observed that the antenna has a bandwidth of 4.08GHz, a return loss of 49.07 dB at the center frequency, a maximum gain of 8.25 dBi and total efficiency of more than 90%. This antenna can be prospective candidate for satellite communications
INFLUENCE OF SKEW ANGLE ON LIVE LOAD DISTRIBUTION IN AN I-BEAM COMPOSITE BRIDGE
No full textBridges constructed on Skew alignment have the most complex behavior. In this study bridges with skew angles of 45 and 63.4 degrees were analyzed under the loading models of 1994 AASHTO code, keeping all other parameters same as those of corresponding right bridges. Whenever a skew is introduced, the bridge (specially bridge deck) behaves as a much stiffer unit relative to its right counterpart, bridge deck tries to bend perpendicular to the skew abutment in the short diagonal direction. Also, part of a loaded lane gets closer to the support, and these features of skew bridge reduces the composite moment of critical interior and exterior girders, i.e. Mcg-skew/Mcg-right . is less than one. Generally, the reduction in composite moment of all the girders in a skew bridge relative to a right bridge, is primarily, due to the fact that part of the loading model gets closer to the supports of a skew bridge. This forces the slab to transmit the loads directly to the abutments, rather than through supporting girders. This observation is substantiated by the fact, that sum of LLF of all the girders in skew bridge is less than one, whereas, this sum of LLF for all the girders in a corresponding right bridge is always equal to one, suggesting that all the LL on skew bridge is not transferred by girders. It should also be noted that, when skew is introduced to a bridge the volume of slab increases as the c/c of girder spacing, b, of a right bridge increases to b/Cos(α) in a skew bridge with an angle of skew equal to α. This increase in volume of a slab increases the stiffness of a bridge structure as a whole, which decreases the deflections and girders composite moments
SLAB ANALYSIS AND DESIGN SOFTWARE BASED ON ACI CODE
No full textThis paper describes, ESSAD (Edge Supported Slab Analysis and Design) Ver 1.0 software based on the ACI code. Commercially available packages for slab analysis and design based on finite element methods are generally demanding for structural engineers as they require extensive knowledge and background in Structural Analysis. However, ESSAD follows the ACI code which is much easier to understand and is widely used as an approximate but sufficiently reliable method for slab analysis and design problems. Therefore, while using ESSAD, an engineer knows precisely what the software is going to perform with the data it requires and what are its limitations and approximations for a specific case. This is extremely important as without knowing the mechanism and limitations of a slab analysis and design package, its use can pose problems
MODEL FOR UNSATURATED FLOW THROUGH SOIL: THEORY AND DEVELOPMENTA real time numerical unsaturated flow model has been developed to describe the movement of water in a homogenous soil The model is based on the Richards equation for partially saturated flow
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A real time numerical unsaturated flow model has been developed to describe the movement of water in a homogenous soil The model is based on the Richards equation for partially saturated flow in porous media along with real boundary conditions in order to make more suitable for real time simulation of water movement and its distribution in a soil matrix. A set of simultaneous equations is obtained by using an implicit finite difference scheme fromthe Richards equation, which is solved by employing an iterative scheme. The model computes the time variation of moisture contents and their corresponding fluxes at different grid points in a given soil system. This paper describes in detail the model theory and its development. At present the model is limited to one dimensional movement of water in unsaturated soil zone in a vertical plane. Various flow processes such as infiltration, moisture redistribution and drainage can easily be determined with the help of this simplified numerical model