John Attia

Power Control for Cognitive Radio Ad Hoc Networks

While FCC proposes spectrum sharing between a legacy TV system and a cognitive radio network to increase spectrum utilization, one of the major concerns is that the interference from the cognitive radio network should not violate the QoS requirements of the primary users. In this paper, we consider the scenario where the cognitive radio network is formed by secondary users with low power personal/portable devices and when both systems are operating simultaneously. A power control problem is formulated for the cognitive radio network to maximize the energy efficiency of the secondary users and guarantee the QoS of both the primary users and the secondary users. The feasibility condition of the problem is derived and both centralized and distributed solutions are provided. Because the co-channel interference are from heterogeneous systems, a joint power control and admission control procedure is suggested such that the priority of the primary users is always ensured. The simulation results demonstrate the effectiveness of the proposed schemes.

Light-weight key distribution and management for Advanced Metering Infrastructure

Electricity grids must cope with rising demand and complexity in a changing world. Smart grid is a promising solution to address these challenges. Recently, Advanced Metering Infrastructure (AMI) is proposed as an integral part of the smart grid that collect and analyze the measurements of energy consumption using the communication network that links the smart meters. The cyber security issues in AMI become very important to guarantee the trustworthiness of the AMI. In order to achieve data confidentiality, privacy and authentication in AMI, security measures using various crypto algorithms will be needed, thus demand key distribution and management schemes. Since the number of electric appliances and devices need to be monitored in households and commercial facilities is large and the devices may have limited computational power and storage, thus novel key distribution and management schemes would be indispensable for the success of securing AMI from cyber attacks. In this work, we propose a light-weight key distribution and management scheme tailored to AMI. Specifically, a group ID based mechanism is proposed to establish the keys for a large amount of entities with small overhead. Security analysis is performed to evaluate the proposed method.

Key Distribution and management for power aggregation and accountability in Advance Metering Infrastructure

Advanced Metering Infrastructure (AMI) is a critical system in smart grid. While readings of aggregated power consumption are needed for near real time response to energy demand, relatively slow paced readings of power demand in each individual household are also very important, because they account for an accurate billing for energy usage at each household, as well as identifying which households may be cheating or may have compromised their meters to report false data. Investigation on properly designed key distribution and management scheme for securely gathering both individual and aggregated meters readings is of paramount importance. Based on this observation, we propose a framework for key distribution and management for both aggregation and accountability in a neighborhood area network employed by a utility company in its power distribution system. Specifically, a key distribution table is set up for each smart meter to carry out homomorphic encryption for secure data aggregation, while a loose time synchronized key scheme is proposed for low rate data collection of each smart meter. Security analysis demonstrate the effectiveness of the proposed scheme.

Teaching electronics with MATLAB

MATLAB is a numeric computation software for engineering and scientific calculations. MATLAB is being used to teach circuit theory, filter design, random processes, control systems and communication theory. MATLAB matrix functions are shown to be versatile in doing analysis of data obtained from electronics experiments. The graphical features of MATLAB are especially useful for display of frequency response of amplifiers and illustrating the principles and concepts of semiconductor physics. The interactive programming and versatile graphics of MATLAB is especially effective in exploring some of the characteristics of devices and electronic circuits.

Increasing electrical and computer engineering enrollment: A multi-faceted approach

In the late 1990s there was a significant decrease in the number of electrical engineering graduates with bachelor degrees in the United States. There was also a drop in the number of Electrical Engineering graduates at Prairie View A&M University (PVAMU) at that time. The Department of Electrical and Computer Engineering wanted to increase the enrollment of its students by using four strategies: (i) creation of a computer engineering program, (ii) raising the retention rate of freshmen students, (iii) attracting community college students, and (iv) offering summer camps to high school students. A Computer Engineering program was created in 2003 to attract students into a growing discipline. The Infinity Project program was used to increase the freshmen retention rate. By using the multi-faceted strategies, the Department of Electrical and Computer Engineering has been able to increase its enrollment. Some recommendations have been made for institutions that want to use some of the strategies to increase their enrollment.

Effects of TID on transistor parameters of dc-dc converters

The output voltages of Buck and Buck-Boost converters, built using IRF250 power MOSFETs, increased with total dose up to 20 Krads(Si). The MOSFET turn-on time was found to increase with total dose. The increased turn-on time of the power MOSFET was found to cause the output voltage of the converters to increase.

Configurable Active-Region-Cutout-Transistor for radiation hardened circuit applications

Active-region-cutout (ARC) technique was developed to modify transistorpsilas active region in order to overcome shorted source-drain in an enclosed poly MOS device. The gate poly extension was made through the unipotential electrode of the active region of drain. This new transistor is named as active-region-cutout-transistor (ARCT). The latter transistor is known to be very tolerant to total ionization dose radiation. ARC technique has an advantage of making MOSFETs with more than three terminals. The ARC can be used to make a compound MOSFET. Two types of amplifier circuits have been studied by replacing transistors with compound ARCTs.

Power Quality and Reliability of University Campus Equipment – Industry and Academic Partnership Program

One area where universities and industry can partner is in the area of power systems reliability and quality curriculum development. Industry can provide the necessary industrial experiences and the academia can offer the theory to support the industrial practices. The purpose of the program was to develop a curriculum in reliability of electrical facilities at Prairie View A&M University through academic-industrial partnership. A new course in reliability analysis of electrical facilities was introduced and taught. Topics that were covered in the course include: reliability and probabilistic theory, Monte Carlo simulations, preventive and predictive maintenance management systems, power generation, transmission and distribution networks, power quality, and field study. The course included demonstrations, inspections and testing of equipment in four buildings at Prairie View A&M University campus. Instructors from Prairie View A&M University and University of Texas at Arlington collaborated with engineers at electrical protection and control to complete this work

Optimization of Home Energy Usage by Intelligently Charging/Discharging EV/PHEV

In this paper, the problem of energy cost minimization for residential home equipped with electric drive vehicles is considered. In future residential homes, electric drive vehicles, including Hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and all-electric vehicles (EVs), are expected to be common due to the growing energy cost and the need for improving efficiency and energy sustainability. In this context, a constrained optimization problem is formulated for home owners to take advantage of controlling when and how the EVs/PHEVs are charged or discharged in order to minimize their energy cost while keeping the vehicle ready for their daily commute. By taking into account the nonlinear characteristics of the battery charging and discharging, and realistic energy pricing from government agencies such as ERCOT (Electric Reliability Council of Texas), a nonlinear programming solution is derived using the sub-gradient search algorithm. Simulation results demonstrate the effectiveness of the proposed scheme.

Substrate coupling in mixed signal integrated circuits

Integrating digital with sensitive analog circuitry has created concerns. The fast switching digital signal creates noise that injects through the doped silicon substrate and travels through it due to its low resistivity and causes damages and bandwidth reduction. In this research work, COMSOL multiphysics was used to extract the substrate coupling parameters subsequently determining the amount of coupling in the substrate and controlling it. Several model configurations were created; such as dual and multiple contacts, which varied the separation between aggressor and victims. Also, the size of the aggressor was increased and a guard ring was added. The results show that spacing can reduce coupling between the aggressor and victim while increasing the area of the aggressor would increase coupling. Also, guard ring can be more efficient than spacing in minimizing coupling.