Taha, M. H. N., H. E. N. mahdy, N. E. - D. M. Khalifa, M. H. N. Taha, and M. A. Lotfi, "Pediatric Online Evidence-Based Medicine Assignment Is a Novel Effective Enjoyable Undergraduate Medical Teaching Tool: A SQUIRE Compliant Study", Medicine (Baltimore) Journal, vol. 94, issue 29, pp. 1178 - 1185, 2015. AbstractPediatric Online Evidence-Based MedicineWebsite

Abstract: Evidence-based medicine (EBM) is delivered through a didactic, blended learning, and mixed models. Students are supposed to construct an answerable question in PICO (patient, intervention, comparison, and outcome) framework, acquire evidence through search of literature, appraise evidence, apply it to the clinical case scenario, and assess the evidence in relation to clinical context.

Yet these teaching models have limitations especially those related to group work, for example, handling uncooperative students, students who fail to contribute, students who domineer, students who have personal conflict, their impact upon progress of their groups, and inconsistent individual acquisition of required skills.

At Pediatrics Department, Faculty of Medicine, Cairo University, we designed a novel undergraduate pediatric EBM assignment online system to overcome shortcomings of previous didactic method and aimed to assess its effectiveness by prospective follow-up during academic years 2012 to 2013 and 2013 to 2014.

The novel web-based online interactive system was tailored to provide sequential single and group assignments for each student. Single assignment addressed a specific case scenario question, while group assignment was teamwork that addressed different questions of same case scenario. Assignment comprised scholar content and skills.

We objectively analyzed students’ performance by criterion-based assessment and subjectively by anonymous student questionnaire.

A total of 2879 were enrolled in 5th year Pediatrics Course consecutively, of them 2779 (96.5%) logged in and 2554 (88.7%) submitted their work. They were randomly assigned to 292 groups. A total of 2277 (89.15%) achieved ≥80% of total mark (4/5), of them 717 (28.1%) achieved a full mark. A total of 2178 (85.27%) and 2359 (92.36%) made evidence-based conclusions and recommendations in single and group assignment, respectively (P < 0.001). A total of 1102 (43.1%) answered student questionnaire, of them 898 (81.48%) found e-educational experience satisfactory, 175 (15.88%) disagreed, and 29 (2.6%) could not decide. A total of 964 (87.47%) found single assignment educational, 913 (82.84%) found group assignment educational, and 794 (72.3%) enjoyed it.

Web-based online interactive undergraduate EBM assignment was found effective in teaching medical students and assured individual student acquisition of concepts and skills of pediatric EMB. It was effective in mass education, data collection, and storage essential for system and student assessment.

Taha, M. H. N., Improving QoS of Data Transmission over Wireless Sensor Networks, , Cairo, Cairo University, 2013. Abstractmnasrtaha_phd_thesis

Wireless Sensor Networks (WSNs) consist of sensor nodes that are spatially distributed. These sensor nodes are connected to each other through wireless technology. They are an important emerging technology that will revolutionize sensing for a wide range of military, scientific, industrial and civilian applications. In many WSN applications, the sensor nodes are deployed in an ad hoc style without careful any pre-planning and engineering. Once deployed, the sensor nodes must have the ability to autonomously organize themselves into a wireless communication network.

New packet scheduling schemes have been developed for real-time data communication. These schemes work on prioritizing packets according to their deadlines. Packet prioritizing cannot support real time applications or assure network lifetime. In extreme traffic environments, large queues may lead to packet delay and packet dropping. Packet dropping leads to energy loss, as a packet could have consumed high energy in order to be delivered to its destination.

The continuous decrease in the size and cost of sensors has motivated intensive research addressing the potential of collaboration among sensors in data. Current research on routing and scheduling in wireless sensor networks focused on energy aware protocols to maximize the lifetime of the network. These researches are scalable to accommodate a large number of sensor nodes. In addition, they are tolerant to sensor damage and battery exhaustion. Sensor networks are deployed to gather information for later analysis, monitoring or tracking of phenomena in real-time.
In WSNs, transmitted packets are queued at intermediate nodes. Each node schedules the queued packets by assigning priorities to each packet. Priorities are assigned to packets according to their deadlines. This method in packet prioritization does not take into consideration either the network life time or energy consumption. Besides, it may lead to dropping high energy valuable packets. In many applications, WSN lifetime is considered a very critical issue, while setting up the network.

In this thesis, a new scheduling scheme, named Energy Based Scheduling scheme is introduced. In this scheme, packets are not only prioritized according to their deadlines but also according to some energy measures related to the network, that are obtained from the network nodes and are used in packet prioritization. The proposed scheme is integrated with the AODV routing protocol. The unused bits in the AODV packets are used by the proposed scheme in assigning sending priorities to each packet in the network. Through this thesis, the proposed scheduling scheme is compared with the Basic Priority Scheduling scheme, using NS-2. Comparisons are done according the network life time, energy consumption and the fairness index measure. The results prove that the Energy Based scheduling scheme increase the network life time and decrease the energy consumption for the goodput packets. On the other hand, the fairness index was affected.

Elmahdy, H. N., and M. H. N. Taha, "The Impact of Packet Size and Packet Dropping Probability on Bit Loss of VoIP Networks", ICGST-CNIR Journal, vol. 8, issue 2, no. 2, pp. 25–29, 2009. Abstractmnasrtaha

The demand for voice over IP (VoIP) applications has increased tremendously through the last two decades. This great demand leads to a great increase in the Quality of Service (QoS) researches and other related fields. One of these fields is the Differentiated Services (DiffServ). In this paper, we studied the effect of the packet size and the effect of random early detection (RED) parameters on the Two Rate Three Color Marker (trTCM) and Single Rate Three Color Marker (srTCM). This is done via a computer simulation using a network simulator (NS-2). Through this paper, we introduce a new simulation model. We will try through this model to find the most suitable parameters such as dropping probability and packet size, in order to achieve better fairness and better goodput. Beside that, we will introduce the standard deviation (SD) as another fairness measuring technique

Taha, M. H. N., N. E. Mahmoud, H. N. Elmahdy, and I. A. Saroit, "Energy Based Scheduling Scheme for Wireless Sensor Networks", CiiT International Journal of Wireless Communication, vol. 4, issue 16, pp. 973-975, 2012. AbstractCU-PDF

Wireless sensor networks (WSNs) have become an attracted research and industry interest. In WSN, each node is attached to a battery, which supply the node with energy required for data sensing, processing and transmission. Transmitted packets are queued at intermediate nodes. Each node schedules the queued packets by assigning priorities to each packet. Priorities are assigned to packets according to their deadlines. This method in packet prioritization does not take into consideration either the network life time or energy consumption. Besides, it may lead to dropping high energy valuable packets. In many applications, WSN lifetime is considered a very critical issue, while setting up the network. In this paper, we paper we introduce new scheduling schema, called Energy Based Scheduling schema. In this schema, packets are not only prioritized according to their deadlines but also to some energy measures related to the network. These energy measures are obtained from the network nodes and are used in packet prioritization. The proposed schema is integrated with the AODV routing protocol. The unused bits in the AODV packets are used by the proposed schema in assigning sending priorities to each packet in the network. Through this paper, we will compare the proposed scheduling schema against the Basic Priority Scheduling schema, using NS-2. Comparisons are done according the network life time and energy consumption.

Khalifa, N. E. M., M. H. N. Hamed, H. E. N. mahdy, and I. A. Tharwat, "A Secure Energy Efficient Schema for Wireless Multimedia Sensor Networks", CiiT International Journal of Wireless Communication, vol. 5, issue 6, pp. 235–246, 2013.
Mahmoud, N. E., M. H. N. Taha, H. N. Elmahdy, and I. A. Saroit, "A Secure Energy Mechanism for WSN and Its Implementation in NS-2", CiiT International Journal of Wireless Communication, vol. 4, issue 16, pp. 984–990, 2012. Abstract

Wireless sensor networks (WSNs) are usually deployed for gathering data from unattended or hostile environments. Therefore, securing data transmission across these environments is a must. Due to the fact that the sensors have a limited power, any security mechanism for sensor network must be energy efficient. In this paper, a secure energy efficient mechanism is introduced with a proposed scenario which leads to a significant improvement in network energy consumption. The mechanism constructs its security features in the application and transport layer as the information that the attackers seek ultimately resides within these layers. We modified the packet format for WSN. Data payload was encrypted by Advanced Encryption Standard (AES) and Message Authentication Code (MAC) was generated to assure data confidentiality and integrity. The energy consumption metric has been taken into considerations while designing and testing the mechanism to make it energy efficient as much as possible. The energy efficiency was achieved by giving a higher priority to the secured packet over the normal packet in the Interface Queue (IFQ). Through this paper, a detailed structure of the proposed mechanism is introduced and implemented using Network Simulator-2 (NS-2). This is the first research that implements security algorithms within NS-2. Since NS-2 does not support any security features before, this research will be a good start to begin using NS-2 as a security simulator.