UET Peshawar Publications Site (University of Engineering and Technology, Peshawar)
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EFFICIENT TREATMENT OF DAIRY EFFLUENT CONTAINING RICH NUTRIENTS USING UP-FLOW MULTILAYER BIO-REACTOR (UMBR)
No full textTwo pilot-scale biological nutrient removal systems having combination of up-flow multilayer bio-rector (UMBR), aeration tank (AT) and sedimentation tank (ST) were installed to check their treatment efficiency for replicated and dairy effluent. These systems were operated under five stages to achieve better results. Hydraulic retention time (HRT), inner recycle (IR), sludge recycle (SR) and organic loading rate (OLR) were systematically changed to optimize the operational conditions. System-I and system-II were operated for dairy and replicated effluent respectively for appropriate analysis. De-nitrification efficiency in up-flow multilayer bioreactor (UMBR) was observed significantly during the operation. It was observed that the involvement of UMBR improved the overall Total Chemical Oxygen Demand (TCOD), Soluble Chemical Oxygen Demand (SCOD). Nitrite-Nitrogen (NO3-N). Total Kjeldahl Nitrogen (TKN), Nitrate Nitrogen (NH3-N) and Total Phosphorous (TP) removal efficiency as compared to other traditional biological treatment systems. Both systems showed practical treatment of replicated as well as dairy effluent. These systems were operated under different set of operational mode and collected results are discussed in term of treatment efficiency of different components. The overall treatment efficiency of the combined systems was also discussed
PERFORMANCE ANALYSIS OF ROUTING PROTOCOLS FOR WIRELESS SENSOR NETWORKS
No full textA Wireless Sensor Network (WSN) is a self-organizing, energy constrained ad hoc network consisting of specialized nodes called motes sensing some phenomenon in an area. WSN may use generic or specialized routing protocols with random node distribution and unpredictable sensing and transceiving patterns with the constraint of limited irreplaceable energy. This paper attempts to compare on-demand reactive routing protocol (AODV) against proactive routing protocol (DSDV). The performance is studied in terms of key performance metrics which include packet delivery fraction, normalized routing load, delay, maximum and average energy. The comparison and analysis is made using Network Simulator 2 (NS-2) with additional Mannasim capability using specialized energy models by varying area of node distribution and node density. The analysis unravels the specific applications for which each protocol is suited
DYNAMICAL SYSTEM ANALYSIS FROM NONLINEAR TRANSITION TO CHAOS FOR A CRACKED PLATE
No full textNonlinear vibrations for an isotropic cracked plate with different possible boundary conditions subjected to transverse harmonic excitation are evaluated. The first mode is examined in detail around the resonant region. A crack consisting of a continuous line is arbitrarily located at the middle and along the x-axis of the plate. The nonlinear dynamical systems analysis of this cracked plate model begins with the stability of the phase states, and the Poincare map followed by a study of the bifurcations that are observed from the analysis of saddle trajectories, and the estimation of the Lyapunov exponent. This leads to the emergence of strange attractors of fractal dimension, the evolution of saddle orbits into chaos, and to the observation that in this system seemingly chaotic behaviour can emerge from perfectly deterministic origins. In this study, the computational methods required are implementations of the Dynamics 2 software package, and specialized code written in Mathematical. Results shows that the system response could be extremely susceptible to changes in the control parameters, and the variation in the half crack length at the plate centre is one influence on the system s bifurcation and chaos
HYDROPOWER PROJECTS AND ENVIRONMENTAL IMPACTS: ADAPTATION STRATEGY FOR ECOSYSTEM RESTORATION THROUGH THE INTERFACE OF RESEARCH AND POLICY
No full textWater is becoming a greater focus of policy makers and planners for the generation of green energy in wake of the climate change. There is a big gap between the supply and demand of electricity in Pakistan. The Pakistan's share in the world's total energy consumption is less than 0.5% and its per capita energy consumption of about 14.2 million British thermal units (Btu) much lower than the technologically advanced countries. Seeking an urgent solution to the deficit forecast of energy, the Government of Pakistan launched an intra-provincial water diversion scheme of Ghazi Barotha Hydro Power Project (GBHPP) in 1995. The aim of this paper is to evaluate GBHPP in terms of benefits versus the adverse impacts on ecological resources and the resulting socio-economic effects on local users. The material and methods used were the collection of water discharge data of river Indus before and after the project, field visits, and Focus Group Discussions (FGDs). The analysis reveals that decrease in water flow in the river, has caused serious adverse impacts on the groundwater in the project area. Besides, the study has quantified the ecological changes due to changed hydrological regime, e.g. decline in fish catch, loss of forests and wildlife. The compensatory water discharges, designed in the project for aquatic life, are inadequate as well as defective by the way of discharge pattern. The paper suggests policy shift in environmental assessment system as well as further research into the residual effects to determine the optimum compensatory water discharges for developing harmony between the project and ecological as well as local needs of the society
CAPACITY ASSESSMENT OF MASONRY WALLS STRENGTHENED WITH INDIGENOUS MATERIALS
No full textIn this paper, capacity assessment of plane brick masonry walls and brick masonry walls strengthened with indigenous materials for mechanical properties and lateral resistance, based on the laboratory test results is discussed. Brick masonry prisms were strengthened with various combinations of plaster, bamboo, wire mesh and confinement with reinforced concrete elements. The masonry specimens were tested by using Portable Structural Testing Equipment (PSTE). The lateral resistance of the masonry walls was determined by using various analytical relationships. The results show that the overall strength of the masonry assemblage increases with the application of the proposed combinations of the indigenous materials
EXPERIMENTAL ANALYSIS OF DEPOSITION OF SANDS BY DRY PLUVIATION TECHNIQUE
No full textObtaining dry density of remolded sand specimens precisely in laboratory has always been an area of interest among researchers in geotechnical engineering. This paper presents the development of a dry pluviation apparatus and its use to prepare dry sand samples in the laboratory to a specified initial relative density. The density and void ratio characteristics of three major sources of sands in Pakistan were investigated through dry pluviation as a function of free fall height. ASTM vibrating table tests on sand samples were also performed to compare index densities with those obtained by dry pluviation apparatus. The results indicate that relative densities up to 100% are achievable in the laboratory using the developed apparatus. A series of regression models have been developed between various parameters associated with dry pluviation
INVESTIGATING DIFFERENT QUEUING MECHANISMS ON ROUTING FOR DIFFERENT TRAFFIC MODELS IN MANETS
No full textA Mobile Ad Hoc Network (MANET) is a collection of wireless mobile nodes that vary its topology forming a temporary network without any pre-existing infrastructure. Queuing mechanisms are techniques which are applied on data packets in network interface buffer. There are a number of queuing mechanisms such as First in First out (FIFO), Priority, Weighted Fair Queuing and Stochastic Fair Queuing. This paper provides a thorough investigation of selected queuing mechanisms (FIFO and Priority) using Constant Bit Rate (CBR) and Exponential traffic models. The performance differentials are analyzed using Network Simulator 2 (NS-2) with respect to a number of key performance metrics under varying mobility and offered load. The analysis concluded can serve in understanding the applications and scenarios where one model is better suited than the other
CAUSES OF DELAY AND COST OVERRUNS DURING CONSTRUCTION PROJECTS IN DEVELOPING COUNTRIES; A CASE STUDY OF PAKISTAN
No full textConstruction projects are frequently delayed due to price escalation of building materials in Pakistan. This research work focused on the main causes of delay is exclusively assessed through questionnaire survey, field visits and discussions to the concerned authorities. A survey was conducted through a questionnaire for identification and evaluation of the important factors result in increasing the cost of materials and delay of construction work in Pakistan. This survey had respondents from client, contractor and consultant firms involved in construction industry. At the same time general public was also a part of it so that an idea about country’s trend would have to be evaluated. The results attained from survey revealed that the major causes of obstacles are the increase in cost of construction materials and delayed due to non-availability of funds in developing countries.According to the contractors escalation of prices is the significant factor for delays in work and cost escalation. The consultants are blaming the poor supervision by contractors. The overall ranking are indicating that all the groups feel that the major factors causing construction delays and overruns in Pakistan are increase of prices, poor contract supervision, monthly payment, hindrances from agencies and shortage of material in their degree of influence
A SURVEY ON AUTO-CONFIGURATION MECHANISMS FOR MOBILE AD-HOC NETWORKS (MANETS)
No full textMobile ad-hoc networks (MANETs) are infrastructure-less networks. Moreover, due to inherent characteristic of mobility of nodes, network merging and partitioning, issues and problems of MANETs are peculiar in nature. Current networking software stacks and services are based on TCP/IP model which is IP address centric. All nodes which want to communicate must have unique IP addresses. Auto-configuration refers to assignment of unique IP addresses to the nodes of MANETs. Due to characteristics of MANETs, assignment of IP addresses to nodes is a non-trivial problem and renders itself as an open issue and potential problem for research. A large number of mechanisms have been proposed for configuring MANET nodes. This paper presents a survey of latest and primitive auto-configuration mechanisms for mobile ad-hoc networks (MANETs)
A NOVEL APPLICATION OF PARTICLE SWARM OPTIMIZATION TECHNIQUE IN SEMI-ACTIVE SUSPENSION SYSTEM CONTROL
No full textThis paper is based on the quarter car semi-active suspension system. Semi-active suspension system proves to be a better choice in comparison with the passive and active systems keeping in view the inherent benefits of better performance, light weight and cost effective design. The semi-active system is driven by a fuzzy logic controller that is based on the feedback of relative displacement of the suspension with respect to the road disturbance and relative velocity across the damper. Fuzzy logic control can cope with the non-linearities of system using heuristic rules. Three gains are incorporated in the system corresponding to the inputs and output of the controller. Particle swarm optimization method is utilized for its better convergence and precision. The technique results in evaluation of appropriate gains that result in superior performance of the designed system. The models are compared on the basis of suspension displacement and tire displacement for ascertaining ride comfort and road handling attributes respectively