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Guntūr, India

Ghani U.,UET Taxila | Ali S.,Atomic Energy Commission | Latif A.,UCET
Life Science Journal | Year: 2013

This paper presents numerical modeling of an open channel with heterogeneous bed strips. The bed formation comprises of checker-board like configuration. At any location along the channel, one half of the bed width was rough and rest half was smooth. The rough side was comprised of gravels. An attempt has been made to investigate how many patches of bed configuration will be required so that flow investigation can be made under periodic boundary condition. Simulation over a length of four patches with periodic boundary condition at inlet/outlet was performed for this purpose. A three dimensional Computational Fluid Dynamics (CFD) numerical model FLUENT was used in this work. The results have been presented in the form of primary velocity contours overlaid by the secondary velocity vectors. These results were calculated at different critical locations along the patches to investigate the flow development. It was observed that the flow patterns in the third and fourth patches are of the same style as that observed in the initial two patches i.e. the developing velocity contours and secondary velocity vectors happened twice in four patches. It can therefore be concluded that two patches are sufficient for any kind of numerical study in these types of bed formations under periodic boundary condition. Source

Ali S.H.,Atomic Energy Commission | Ghani U.,UET | Latif A.,UCET | Ijaz N.,UET | Pasha G.A.,UET
Life Science Journal | Year: 2013

The experiments in an open-channel flume with modeled vegetated weir-like structures have been used to understand how the flow is affected by them. Laser Doppler velocimeter measurements of the water flow velocities over trapezoidal vegetated and non-vegetated weir-like structures (dike, groyne) have been made. The measurements extended to a distance of 20 weir heights downstream of the weir crest, it also included the flow separation zone behind the weir crest. The Reynolds's number was of the order of 104 in the flume, and imperfect flow conditions with Froude number<0.4 above the weir crest were considered. Two discharge values were considered in the experimental work. A comparison between the flow characteristics of vegetated and non vegetated weir-like structure was made. The variables investigated included longitudinal and vertical velocity components. Reynolds shearing stresses have also been investigated. The measured mean and turbulent velocities provided more detailed insight about the flow behind vegetated weirs. Strong vortices and turbulent intensities in region especially downstream of vegetated weir crest showed that the flow in the region near bed (on downstream slope of weir the recirculation zone is the main contributor) and at the top of the modeled vegetation is very unstable and leads to the formation of the coherent structures and it is the area of significant mass and momentum exchange. The results indicated that regaining of the logarithmic velocity profile behind the vegetated weir-like structures are delayed due to the presence of vegetation. Source

Ali S.,Atomic Energy Commission | Ghani U.,UET Taxila | Latif A.,UCET
Life Science Journal | Year: 2013

The present paper presents results from an experimental work in an open channel flow. The open channel contains a weir-like obstruction with different leeward slopes. Two discharge values have been used under subcritical flow conditions. The objective of the present study is to investigate the flow behavior behind a vegetated obstacle. The characteristics explored included the turbulent kinetic energy and recirculation zone behind the vegetated obstacles. It was observed from this work that the TKE has higher values in recirculation regions. On the other hand it was also found to be of high intensity in the vegetated zones of the flow. However TKE was maximum and positive close to the bed at a section at the end of the weir crest and it was negative below the top of the vegetation dowels. As far as recirculation region was concerned, it was observed that the vegetation had no effect on the recirculation zone behind the vegetated weir. In case of weir with mild downstream slope (1:7), the flow separation zone vanished and the energy head loss in this case decreased due to the decrease in form drag of the weir. Source

Karthikeyan M.,UCET | Venkatalakshmi K.,UCET
2012 3rd International Conference on Computing, Communication and Networking Technologies, ICCCNT 2012 | Year: 2012

Efficient consumption of energy of sensor node in Wireless Sensor Networks (WSN's) is one of the noticeable challenges nowadays. We can prolong the lifetime of WSN by well-organized clustering of nodes. In this work we suggest PSO incorporated cuckoo search optimization algorithm for clustering in energy aware way and compared it with cuckoo search algorithm. Through efficient clustering of WSN we are reducing the total communication distance as well as providing more probability for higher energy node to be cluster head. The proposed algorithm provides improved lifetime than LEACH, SEP and cuckoo search algorithms. © 2012 IEEE. Source

Jegatha Deborah L.,UCET | Baskaran R.,Anna University | Kannan A.,Anna University | Vijayakumar P.,UCET
Malaysian Journal of Computer Science | Year: 2013

Performances of the students in learning a programming course is not same, since learning to program is greatly influenced by two dominating factors namely self-efficacy and mental efforts. Prior research efforts have shown that high self-efficacy can have an increased effect of being a trained programmer, especially in an intelligent agent based pair programming system. The main objective of this work is to increase the self-efficacy of the students by providing prior-learning experiences. This experience is facilitated by recommendation agents that provide suitable E-Learning programming course contents based on identifying their individual learning styles which can be used as a factor of prior self-learning computing experience. This helps in increasing the programming abilities when learning in an agent-based pair programming environment subsequently. Moreover, the proposed system analyzes the educational effects of the students learning using pair programming agents based on increased self-efficacy. Source

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