Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Communication channels (2)
- Communication networks (2)
- Communication system control (2)
- Antenna selection (1)
- Asymptotic stability (1)
-
- Broadcasting (1)
- Chaos (1)
- Chaotic communication (1)
- Chaotic communications (1)
- Closed-loop networked control system (1)
- Computational modeling (1)
- Concurrent computing (1)
- Control systems (1)
- Delay effects (1)
- Distributed computing (1)
- Feedback control (1)
- Fixed order controllers (1)
- Fusion power generation (1)
- H2 minimizing controllers (1)
- Hybrid (1)
- Large-scale economics (1)
- MIMO systems (1)
- Network architectures (1)
- Nonlinear control systems (1)
- Nonlinear dynamical systems (1)
- Photodetectors (1)
- Q-parameterization (1)
- RF Photonics (1)
- Regional Economic Development; Public University Community Service; Wealth Creation; Net Job Creation (1)
- Sensors (1)
Articles 1 - 14 of 14
Full-Text Articles in Entire DC Network
Discrete Asymptotic Abstractions Of Hybrid Systems, Chaouki T. Abdallah, Jorge L. Piovesan, Herbert G. Tanner
Discrete Asymptotic Abstractions Of Hybrid Systems, Chaouki T. Abdallah, Jorge L. Piovesan, Herbert G. Tanner
Electrical & Computer Engineering Faculty Publications
In this paper we introduce the notion of finite time mode abstraction to relate a hybrid automaton to a timed automaton that preserves the stability and reachability properties of the former. The abstraction procedure discards the continuous dynamics of each mode in the hybrid automaton completely, keeping only the information about the maximum time in which the continuous state makes a discrete jump. This information is used to construct a timed automaton, based on the original hybrid automaton, and to prove that the stability and reachability properties of the original system are retained in the abstract timed automaton. In the …
Introducing Agility In Hybrid Communication Systems And Sensors, Chaouki T. Abdallah, C.G. Christodoulou, J. Khoury, P. K. Yu, M. Franceschetti
Introducing Agility In Hybrid Communication Systems And Sensors, Chaouki T. Abdallah, C.G. Christodoulou, J. Khoury, P. K. Yu, M. Franceschetti
Electrical & Computer Engineering Faculty Publications
This paper presents a new approach in dealing with hybridization issues in communication systems or sensors. The thrust is to separate the logical network (sensor) infrastructure from the physical one. Here we show how we can exploit concepts such as persistent identification which we believe is crucial to be able to connect a variety of heterogeneous devices in a network that grows, and that is robust to failures. A vital characteristic of our architecture is the ability to accommodate a variety of heterogeneous devices and subsystems. Several examples of hybridization of sensors at the physical, logical, and network levels are …
Bilateral Teleoperation Of Mobile Robot Over Delayed Communication Network: Implementation, Chaouki T. Abdallah, Oscar Martinez-Palafox, Dongjun Lee, Mark W. Spong, I. Lopez
Bilateral Teleoperation Of Mobile Robot Over Delayed Communication Network: Implementation, Chaouki T. Abdallah, Oscar Martinez-Palafox, Dongjun Lee, Mark W. Spong, I. Lopez
Electrical & Computer Engineering Faculty Publications
In a previous paper we proposed a bilateral teleoperation framework of a wheeled mobile robot over communication channel with constant time delay. In this paper we present experimental results. Our goal is to illustrate and validate the properties of the proposed scheme as well as to present practical implementation issues and the adopted solutions. In particular, the bilaterally teleoperated system is passive and the system is stable in the presence of time delay. Internet has been used as the communication channel and a buffer has been implemented to maintain a constant time delay and to handle packet order.
Recent Advances On Linear Control Theory Under Communication Constraints: A Survey, Chaouki T. Abdallah, Ivan Lopez
Recent Advances On Linear Control Theory Under Communication Constraints: A Survey, Chaouki T. Abdallah, Ivan Lopez
Electrical & Computer Engineering Faculty Publications
Recent developments in networked control systems have focused on the issue of communications constraints. In this paper, we summarize the main results for stabilization and performance of networked control systems from an information theoretic point of view.
Exploiting Multiuser Diversity In Scheduling Mimo Cellular Systems, Chaouki T. Abdallah, M. Hayajneh, M. Costa
Exploiting Multiuser Diversity In Scheduling Mimo Cellular Systems, Chaouki T. Abdallah, M. Hayajneh, M. Costa
Electrical & Computer Engineering Faculty Publications
In this paper we consider a scheme of packet scheduling for the forward link of a MIMO cellular system, to increase system capacity by exploiting multiuser diversity based on spatial multiplexing (SM). The proposed scheme exhibits considerable increases in system capacity compared to commonly used schemes, while, at the same time, giving a fair chance of channel access to all users regardless of their channel fading status.
Resource-Constrained Load Balancing Controller For A Parallel Database, Chaouki T. Abdallah, J. Douglas Birdwell, Zhong Tang, John Chiasson, Majeed M. Hayat
Resource-Constrained Load Balancing Controller For A Parallel Database, Chaouki T. Abdallah, J. Douglas Birdwell, Zhong Tang, John Chiasson, Majeed M. Hayat
Electrical & Computer Engineering Faculty Publications
The critical features of the load balancing problem are the delayed receipt of information and transferred load. Load distribution and task processing contend for the same resources on each computational element. This paper documents experimental results using a previously reported deterministic dynamic nonlinear system for load balancing in a cluster of computer nodes used for parallel computations in the presence of time delays and resource constraints. The model accounts for the trade-off between using processor resources to process tasks and the advantage of distributing the load evenly between the nodes to reduce overall processing time. The control law is implemented …
Practical Issues In Networked Control Systems, Chaouki T. Abdallah, Ivan Lopez, J. L. Piovesan, D. Lee, O. Martinez, M. Spong, R. Sandoval
Practical Issues In Networked Control Systems, Chaouki T. Abdallah, Ivan Lopez, J. L. Piovesan, D. Lee, O. Martinez, M. Spong, R. Sandoval
Electrical & Computer Engineering Faculty Publications
In this paper we expose experimental issues faced in a closed-loop networked control system. We also propose some compensation actions, and evaluate their performance for different experimental setups, focusing specifically on time delays.
Experimental Investigation Of Active Feedback Control Of Turbulent Transport In A Magnetized Laboratory Plasma, Chaouki T. Abdallah, M. Gilmore, S. Xie, S. Will, P. Ram, A.G. Lynn, C. Watts, A.S. Ware, L. Pangioni
Experimental Investigation Of Active Feedback Control Of Turbulent Transport In A Magnetized Laboratory Plasma, Chaouki T. Abdallah, M. Gilmore, S. Xie, S. Will, P. Ram, A.G. Lynn, C. Watts, A.S. Ware, L. Pangioni
Electrical & Computer Engineering Faculty Publications
Summary form only given. Many toroidal fusion devices now routinely generate edge and/or core transport barriers, where heat and particle transport are reduced far below Bohm diffusion levels. However, minimal particle transport is not necessarily desirable, since it can lead to core impurity accumulation, or alpha particle buildup. Ideally, active, stable control over the transport, rather than simple minimization, could be obtained. To this effect, research is now underway to investigate active control of particle transport. Turbulence and transport dynamics are, of course, strongly nonlinear, and apparently not deterministic. However, modern nonlinear control methods now exist, such as chaotic control …
Identifier-Based Discovery In Large-Scale Networks, Chaouki T. Abdallah, Joud Khoury
Identifier-Based Discovery In Large-Scale Networks, Chaouki T. Abdallah, Joud Khoury
Electrical & Computer Engineering Faculty Publications
The design of any network mechanism that requires collaboration among selfish agents could only benefit from accounting for the complex social and economic interactions and incentives of the agents using the design. This chapter presents a broad treatment of the main economic issues that arise in the context of identifier-based discovery on large scale networks, particularly on the Internet. An “identified” object (such as a node or service), referred to as a player, demands to be discoverable by the rest of the network on its “identifier”. A discovery scheme provides such a service to the players and incurs a cost …
A Randomized Approach To The H2/H? Control Problem Via Q-Parameterization, Chaouki T. Abdallah, Kenneth R. Horspool, R. Scott Erwin, Peter Dorato
A Randomized Approach To The H2/H? Control Problem Via Q-Parameterization, Chaouki T. Abdallah, Kenneth R. Horspool, R. Scott Erwin, Peter Dorato
Electrical & Computer Engineering Faculty Publications
We show that the mixed H2/H? control problem can be efficiently solved using randomized algorithms. Q-parameterization provides a mechanism to search over all stabilizing controllers, and thus gives us the ability to search for H2 minimizing controllers, while still providing stability robustness. Finally, we are able to show that we can get results comparable to a more traditional approach such as gradient search, but in addition, we can solve more complex problems. With very little modification, we are able to deal with multiple objectives, plant uncertainty, and fixed order controllers.
Load Balancing In The Presence Of Random Node Failure And Recovery, Chaouki T. Abdallah, Sagar Dhakal, Majeed M. Hayat, Jorge E. Pezoa, J. Doug Birdwell, John Chiasson
Load Balancing In The Presence Of Random Node Failure And Recovery, Chaouki T. Abdallah, Sagar Dhakal, Majeed M. Hayat, Jorge E. Pezoa, J. Doug Birdwell, John Chiasson
Electrical & Computer Engineering Faculty Publications
In many distributed computing systems that are prone to either induced or spontaneous node failures, the number of available computing resources is dynamically changing in a random fashion. A load-balancing (LB) policy for such systems should therefore be robust, in terms of workload re-allocation and effectiveness in task completion, with respect to the random absence and re-emergence of nodes as well as random delays in the transfer of workloads among nodes. In this paper two LB policies for such computing environments are presented: The first policy takes an initial LB action to preemptively counteract the consequences of random failure and …
Masters And Novices, Chaouki T. Abdallah
Masters And Novices, Chaouki T. Abdallah
Electrical & Computer Engineering Faculty Publications
On 5–6 June 2005, the Electrical and Computer Engineering Department of the University of New Mexico organized a workshop to celebrate the career of Peter Dorato. The event was held at Los Poblanos Inn, an historic inn and cultural center located in the village of Los Ranchos de Albuquerque, New Mexico. Los Poblanos Inn, which is listed on both the New Mexico and National Registers of Historic Places, has 25 acres of agricultural fields and extensive historic gardens. Both Los Poblanos Inn and La Quinta Cultural Center were designed by the Southwest’s foremost architect John Gaw Meem, the “father of …
Symposium On Systems, Control, And Networks In Honor Of Professor Pravin Varaiya On His 65th Birthday, Chaouki T. Abdallah
Symposium On Systems, Control, And Networks In Honor Of Professor Pravin Varaiya On His 65th Birthday, Chaouki T. Abdallah
Electrical & Computer Engineering Faculty Publications
The Symposium on Systems, Control, and Networks was held on 5–7 June 2005 in Berkeley, California, in honor of Prof. Pravin Varaiya on the occasion of his 65th birthday. Pravin Varaiya has been on the faculty of the Department of Electrical Engineering and Computer Sciences of the University of California, Berkeley, since he completed his Ph.D. there in 1966.
Economic Development At A Public University - A Process Model And Associated Metrics, Andres C. Salazar
Economic Development At A Public University - A Process Model And Associated Metrics, Andres C. Salazar
Electrical & Computer Engineering Faculty Publications
A university has long been considered an institution of higher learning with the immutable dual goals of research and teaching. A “public” university, however, has also had the founding principle of service, the performance of which is often linked to the region from which it receives public funds. Recently, this service component has morphed to playing an active role in regional economic development. This paper reviews the factors that have led to the situation in which a public university must define a relevant and significant set of objectives for itself in improving the economy of the community it serves. Further, …