Showing papers by "K. Chandrasekaran published in 2009"
28 Jul 2009
TL;DR: The theory of Petri nets is exploited to verify reachability and soundness of a cooperative workflow model, which is a modified version of Bonita workflow model.
Abstract: This paper exploits the theory of Petri nets to verify reachability and soundness of a cooperative workflow model. First, we outline a cooperative workflow model, which is a modified version of Bonita workflow model. Bonita is open source cooperative workflow management software which is an ongoing project from object web consortium. Then we describe the cooperative workflow model using a special kind of Petri net called Wf-net. Next we employ WF-net for verification of the model for reachability and soundness properties. The Petri net based verification shows that the model is reachable and sound.
4 citations
22 Jan 2009
TL;DR: This paper introduces a notation, called Ambi Graphs, for specifying the work flow in any ambient intelligence system, and shows how an ambi graph is elegant when it is designed to adapt to the wide range of users that work on it.
Abstract: In computing, ambient intelligence (AmI)[2,3] refers to electronic environments that are sensitive and responsive to the presence of people. In an ambient intelligent world, devices work in concert to support people in carrying out their everyday life activities, tasks and rituals in easy, natural way using information and intelligence that is hidden in the network connecting these devices. The ambient intelligence paradigm builds upon ubiquitous computing [4] and human-centric computer interaction design. In this paper, we introduce a notation, called Ambi Graphs, for specifying the work flow in any ambient intelligence system. An ambi graph is elegant when it is designed to adapt to the wide range of users that work on it.
1 citations
01 Jan 2009
TL;DR: In this article, the electric and magnetic fields generated by a near-by lightning were computed for different heights ranging from 10 m to 2 km above the ground and for the lateral distances varying from 20 m to two km from the lightning return stroke.
Abstract: This paper presents the computed results of electric and magnetic fields generated by the near by lightning. The electric and magnetic fields have been computed for different heights ranging from 10 m to 2 km above the ground and for the lateral distances varying from 20 m to 2 km from the lightning return stroke. For airborne vehicles e.g, satellite launch vehicles, missiles etc, it has become necessary to understand the behavior of these when illuminated by a strong electromagnetic fields generated by a near by lightning. The coupling of these fields with the above system could be by means of the leakage of the transient electromagnetic fields through the joints of the vehicles, leakage through the improperly shielded cables, leaks through the edges of closed doors etc. This results the generation of transient voltages and currents with the internal circuitry of such systems. The objective of this work is to compute the fields along the airborne vehicles when excited by plane electromagnetic fields. These plane electromagnetic fields consist of electric and magnetic fields, where the fields could get modified at different heights from the ground plane and for different distances from the lightning channel. Keywords-airborne vehicle; lightning; transient electromagnetic fields; may induce over voltages which may results malfunction ofthe system. The effect of variation in the rate of rise of lightning current (di/dt) and the velocity of the return stroke current on the radiate electric and magnetic fields has been studied. The electric and magnetic fields (assuming the ground as a perfect conductor) at different heights varying from 10 m to 2000 m and for lateral distance varying from 20 m to 2000 m from the lightning channel have been computed. The significance of return stroke velocity on the electromagnetic fields generated by the lightning has been studied.
01 Dec 2009
TL;DR: In this paper, the electric and magnetic fields generated by a near-by lightning were computed for different heights ranging from 10 m to 2 km above the ground and for the lateral distances varying from 20 m to two km from the lightning return stroke.
Abstract: This paper presents the computed results of electric and magnetic fields generated by the near by lightning. The electric and magnetic fields have been computed for different heights ranging from 10 m to 2 km above the ground and for the lateral distances varying from 20 m to 2 km from the lightning return stroke. For airborne vehicles e.g. satellite launch vehicles, missiles etc, it has become necessary to understand the behavior of these when illuminated by a strong electromagnetic fields generated by a near by lightning. The coupling of these fields with the above system could be by means of the leakage of the transient electromagnetic fields through the joints of the vehicles, leakage through the improperly shielded cables, leaks through the edges of closed doors etc. This results the generation of transient voltages and currents with the internal circuitry of such systems. The objective of this work is to compute the fields along the airborne vehicles when excited by plane electromagnetic fields. These plane electromagnetic fields consist of electric and magnetic fields, where the fields could get modified at different heights from the ground plane and for different distances from the lightning channel.