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Banhā, Egypt

Shaidan N.H.,Petronas University of Technology | Eldemerdash U.,Petronas University of Technology | Awad S.,Banha University
Journal of the Taiwan Institute of Chemical Engineers | Year: 2012

Ion exchange represents an efficient technique for removing of heavy metals from wastewater effluents. Limited number of studies focuses on fixed bed performance for metal removal. In this study, the removal of Ni 2+ from synthetic wastewater using a strong acidic cation exchange resin in a fixed bed columns was investigated. The experiments were conducted at different pH (3-7) and initial heavy metal concentrations (1.8, 2.8 and 3.8g Ni/L). Investigation of the regeneration effect on the resin was conducted. The removal efficiency and rate of removal are shown on the breakthrough curves and the kinetic study of the process was determined. The Thomas model was applied to follow the exchange dynamics, the results from experimental work were compared to those using Thomas model, it is shown that the calculated breakthrough curves agreed well with the measured ones. The metal level in the treated wastewater was examined using the atomic absorption spectrophotometer to show that the Ni 2+ concentration complies with the standard environmental regulations limits. © 2011 Taiwan Institute of Chemical Engineers.

Khedr A.M.,University of Sharjah | Osamy W.,Banha University
Information Sciences | Year: 2011

Many applications of wireless sensor networks (WSNs) require the tracking and the surveillance of target objects. The information to be gathered about the target may be related to only a particular monitored sub-area. Therefore, it is desirable to direct queries only to the nodes monitoring this particular area and for energy saving reasons, only the queried nodes should respond. In this paper, we introduce two new efficient distributed algorithms for finding the minimum number of connected perimeter sensor nodes that are sufficient to cover the perimeter of queried region, where the union of their sensing regions covers the perimeter of queried area. The simulation results show that our proposed algorithms achieve significant reduction in communication load, while preserving full perimeter coverage. © 2011 Elsevier Inc. All rights reserved.

Ahmed F.S.,Banha University | Shafy M.,NCNSRC | Abd El-megeed A.A.,National Institute for Standards of Egypt | Hegazi E.M.,NCNSRC
Materials and Design | Year: 2012

Seals made of acrylonitrile-butadiene rubber (NBR) are one of the classified seals used in nuclear facilities. But at high irradiation doses the physical and mechanical properties of NBR are adversely affected due to the degradation induced by radiation and hence affect the sealing performance reducing their service life. In order to improve the NBR sealing performance, antioxidants can be added to the NBR compounds. N-N-substituted p-phenylene diamines (PPDs) antioxidants are selected to improve the resistance of NBR seals against gamma irradiation up to 5. MGy. The effect of addition of different PPDs on the mechanical and physical properties of the NBR seals is investigated. Three types of antioxidants which are N-isopropyl-N'-phenyl-p-phenylene diamine (IPPD), phenyl B-naphthylamine (PBN), and N-(1,3-dimethylbutyl)-N-phenyl-p-phenylene diamine (6PPD) are chosen. The physical and mechanical properties of these NBR compounds were evaluated by measuring crosslinking density, the tensile strength, and the percentage of elongation as well as hardness and abrasion resistance. The results of the present study show that the addition of 6PPD as a candidate antioxidant to NBR seal material gives the best physical and mechanical performance compared to the other studied antioxidants. © 2011 Elsevier Ltd.

Khedr A.M.,Zagazig University | Osamy W.,Banha University
Journal of Parallel and Distributed Computing | Year: 2011

Target tracking is an important sensing application of wireless sensor networks. In these networks, energy, computing power, and communication bandwidth are scarce. We have considered a random heterogeneous wireless sensor network, which has several powerful nodes for data aggregation/relay and large number of energy-constrained sensor nodes that are deployed randomly to cover a given target area. In this paper, a cooperative approach to detect and monitor the path of a moving object using a minimum subset of nodes while maintaining coverage and network connectivity is proposed. It is tested extensively in a simulation environment and compared with other existing methods. The results of our experiments clearly indicate the benefits of our new approach in terms of energy consumption. © 2011 Elsevier Inc. All rights reserved.

Khedr A.M.,University of Sharjah | Osamy W.,Banha University
Journal of Parallel and Distributed Computing | Year: 2012

All properties of mobile wireless sensor networks (MWSNs) are inherited from static wireless sensor networks (WSNs) and meanwhile have their own uniqueness and node mobility. Sensor nodes in these networks monitor different regions of an area of interest and collectively present a global overview of monitored activities. Since failure of a sensor node leads to loss of connectivity, it may cause a partitioning of the network. Adding mobility to WSNs can significantly increase the capability of the WSN by making it resilient to failures, reactive to events, and able to support disparate missions with a common set of sensor nodes. In this paper, we propose a new algorithm based on the divide-and-conquer approach, in which the whole region is divided into sub-regions and in each sub-region the minimum connected sensor cover set is selected through energy-aware selection method. Also, we propose a new technique for mobility assisted minimum connected sensor cover considering the network energy. We provide performance metrics to analyze the performance of our approach and the simulation results clearly indicate the benefits of our new approach in terms of energy consumption, communication complexity, and number of active nodes over existing algorithms. © 2012 Elsevier Inc. All rights reserved.

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