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Kyung Chang Lee

Other affiliations: Pusan National University
Bio: Kyung Chang Lee is an academic researcher from Pukyong National University. The author has contributed to research in topics: Fieldbus & Profibus. The author has an hindex of 20, co-authored 116 publications receiving 1605 citations. Previous affiliations of Kyung Chang Lee include Pusan National University.


Papers
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Journal ArticleDOI
TL;DR: The performance evaluation of the switched Ethernet on an experimental network testbed along with an implementation method for using the switch for industrial automation and the elimination of uncertainties in the network operation leads to the dramatically improved performance.

149 citations

Journal ArticleDOI
TL;DR: A novel non-terminal-based approach using an array of pyroelectric infrared sensors (PIR sensors) that can detect residents that is evaluated experimentally on a test bed.
Abstract: Smart home is expected to offer various intelligent services by recognizing residents along with their life style and feelings. One of the key issues for realizing the smart home is how to detect the locations of residents. Currently, the research effort is focused on two approaches: terminal-based and non-terminal-based methods. The terminal-based method employs a type of device that should be carried by the resident while the non-terminal-based method requires no such device. This paper presents a novel non-terminal-based approach using an array of pyroelectric infrared sensors (PIR sensors) that can detect residents. The feasibility of the system is evaluated experimentally on a test bed

142 citations

Journal ArticleDOI
TL;DR: An analytical performance evaluation of the switched Ethernet with multiple levels from timing diagram analysis, and experimental evaluation from an experimental testbed of networked control system are presented.
Abstract: The industrial network, often referred to as fieldbus, becomes an indispensable component for intelligent manufacturing systems. Thus, in order to satisfy the real-time requirements of field devices such as sensors, actuators, and controllers, numerous fieldbus protocols have been developed. But, the application of fieldbus has been limited due to the high cost of hardware and the difficulty in interfacing with multivendor products. As an alternative to fieldbus, the Ethernet (IEEE 802.3) technology is being adapted to the industrial environment. However, the crucial technical obstacle of Ethernet is its nondeterministic behavior that cannot satisfy the real-time requirements. Recently, the switched Ethernet becomes a very promising alternative for real-time industrial application due to the elimination of uncertainties in Ethernet. This paper focuses on the application of the switched Ethernet with multiple levels (that is, cascade structure with multiple switching hubs) for real-time industrial networking. More specifically, this paper presents an analytical performance evaluation of the switched Ethernet with multiple levels from timing diagram analysis, and experimental evaluation from an experimental testbed of networked control system

119 citations

Journal ArticleDOI
TL;DR: The structure of a network-based fire-detection system via the controller area network (CAN) and the design method of a CAN communication network are described to evaluate the feasibility of using such a home automation protocol in a smart home.
Abstract: This paper presents a network-based fire-detection system via the controller area network (CAN) to evaluate the feasibility of using such a home automation protocol in a smart home In general, a conventional fire-detection system has several shortcomings, such as weakness to noise, because it uses an analog transmission with 4-20 mA current lines Hence, as an alternative to the conventional system, this paper describes the structure of a CAN-based fire-detection system and the design method of a CAN communication network The performance of the proposed system is evaluated through experimental tests The CAN has several advantages, such as low cost and ease of implementation, as compared to the other low layers of the BACNet, such as Ethernet or ARCNET Therefore, if the CAN is selected for the low layer of the BACNet, a home automation system can be implemented more effectively

104 citations

Journal ArticleDOI
TL;DR: A method to integrate mobile devices such as a mobile robot, automated guided vehicle, and unmanned container transporter to form an automated material handling system using the Profibus-IEEE 802.11 network for industrial applications involving mobile devices.
Abstract: This paper focuses on a method to integrate mobile devices such as a mobile robot, automated guided vehicle, and unmanned container transporter to form an automated material handling system. In this paper, the stationary devices are connected via a Profibus network while the mobile devices are communicating via an IEEE 802.11 wireless LAN. In order to integrate these two networks, a protocol converter is developed on a PC platform that runs two interacting processes with shared internal buffers. The protocol converter performs a role of translator between two different protocols by converting the format of a data frame. In addition to this basic conversion function, the protocol converter has a virtual polling algorithm to reduce the uncertainty involved in accessing the wireless network. Finally, the integrated network. of Profibus and IEEE 802.11 is experimentally evaluated for its data latency and throughput, which shows the feasibility of the Profibus-IEEE 802.11 network for industrial applications involving mobile devices.

83 citations


Cited by
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[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
TL;DR: The NCS and its different forms are introduced and discussed, and different fields and research arenas such as networking technology, network delay, network resource allocation, scheduling, network security in real-time NCSs, integration of components on a network, fault tolerance, etc.
Abstract: Networked control systems (NCSs) have been one of the main research focuses in academia as well as in industry for many decades and have become a multidisciplinary area. With these growing research trends, it is important to consolidate the latest knowledge and information to keep up with the research needs. In this paper, the NCS and its different forms are introduced and discussed. The beginning of this paper discusses the history and evolution of NCSs. The next part of this paper focuses on different fields and research arenas such as networking technology, network delay, network resource allocation, scheduling, network security in real-time NCSs, integration of components on a network, fault tolerance, etc. A brief literature survey and possible future direction concerning each topic is included.

1,053 citations

Journal ArticleDOI
TL;DR: The main methodologies suggested in the literature to cope with typical network-induced constraints, namely time delays, packet losses and disorder, time-varying transmission intervals, competition of multiple nodes accessing networks, and data quantization are surveyed.
Abstract: Networked control systems (NCSs) have, in recent years, brought many innovative impacts to control systems. However, great challenges are also met due to the network-induced imperfections. Such network-induced imperfections are handled as various constraints, which should appropriately be considered in the analysis and design of NCSs. In this paper, the main methodologies suggested in the literature to cope with typical network-induced constraints, namely time delays, packet losses and disorder, time-varying transmission intervals, competition of multiple nodes accessing networks, and data quantization are surveyed; the constraints suggested in the literature on the first two types of constraints are updated in different categorizing ways; and those on the latter three types of constraints are extended.

989 citations

Journal ArticleDOI
Tai C Yang1
10 Jul 2006
TL;DR: In this article, a survey on networked control systems (NCSs) is presented, and a simple framework and some general formulations for the study of NCSs are proposed.
Abstract: A survey on networked control systems (NCSs), published in a previous paper, is updated and extended. A simple framework and some general formulations for the study of NCSs are proposed. In addition to the survey on NCSs, the impact of NCSs on traditional large-scale system control methodologies with a related application is also reviewed.

726 citations

Journal ArticleDOI
TL;DR: This paper discusses a selection of promising and interesting research areas in the design of protocols and systems for wireless industrial communications that have either emerged as hot topics in the industrial communications community in the last few years, or which could be worthwhile research Topics in the next few years.
Abstract: In this paper we discuss a selection of promising and interesting research areas in the design of protocols and systems for wireless industrial communications. We have selected topics that have either emerged as hot topics in the industrial communications community in the last few years (like wireless sensor networks), or which could be worthwhile research topics in the next few years (for example cooperative diversity techniques for error control, cognitive radio/opportunistic spectrum access for mitigation of external interferences).

696 citations