• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.21-22
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• 2007

Topology processing is indispensable basic function as it generate a real-time BUS-BRANCH model in Energy Management Systems because most application softwares such as state estimation, power flow, etc., require BUS-BRANCH circuit data. This paper propose an expert system to generate BUS-BRANCH circuit model using Artificial Intelligence technology and it is applied to 154kV distribution substations.

• Journal of Korean Port Research
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• v.8 no.2
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• pp.79-105
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• 1994

Today travel demand in the City of Pusan is increasing with the wide scope of activity and the better living circumstances as a big city with a population of about 4 million. Also, the transportation problem of Pusan city becomes one of the severest urban problems with travel demand increasing in spite of the continuous expansion of the transportation facilities. The purpose in this study is to find the travel characteristics on the arterial under the study, construct the optimal Transportation System Management(TSM) which could increase the travel capacity of the arterial based upon the optimal travel systems constructed. Thus, it was concluded that more emphasis should be of the automobiles into the Downtown areas, increase the travel capacity of the arterial through Mass Transportation System(MTS) including the HOV lanes or the Bus Exclusive Lanes instead.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.664-669
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• 1994

This paper focuses on development and implementation of a performance management algorithm for IEEE802.4 token bus networks to serve large-scale integrated manufacturing systems. Such factory automation networks have to satisgy delay constraints imposed on time-critical messages while maintaining as much network capacity as possible for non-time-critical messages. This paper presents a network perfomance manager that adjusts queue apacity as well as timers by using a set of fuzzy rules and fuzzy inference mechanism. The efficacy of the performance management has been demonstrated by a series of simulation experiments.

• Journal of Platform Technology
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• v.11 no.3
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• pp.3-11
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• 2023

Real-time control systems are growing rapidly as infrastructure technologies such as IoT and mobile communication develop and services that value real-time such as factory management and vehicle operation checks increase. Various solutions have been proposed to increase the time sensitivity of this system, but most real-time control systems are currently composed of local servers and multiple clients located in control stations, which are transmitted to local servers where control systems are located. In this paper, we proposed an edge computing-based real-time control model that can reduce the time it takes for the bus information system, one of the real-time control systems, to provide the information to the user at the time it collects the information. Simulating the existing model and the edge computing model, the edge computing model confirmed that the cost for users to receive data is reduced from at least 10% to up to 80% compared to the existing model.

• Journal of Electrical Engineering and Technology
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• v.4 no.3
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• pp.337-345
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• 2009

Deregulation in power industry has made the reactive power ancillary service management a critical task to power system operators from both technical and economic perspectives. Reactive power management in power systems is a complex combinatorial optimization problem involving nonlinear functions with multiple local minima and nonlinear constraints. This paper proposes a practical market-based reactive power ancillary service management scheme to tackle the challenge. In this paper a new model for voltage security and reactive power management is presented. The proposed model minimizes reactive support cost as an economic aspect and insures the voltage security as a technical constraint. For modeling validation study, two optimization algorithm, a genetic algorithm (GA) and particle swarm optimization (PSO) method are used to solve the problem of optimum allocation of reactive power in power systems under open market environment and the results are compared. As a case study, the IEEE-30 bus power system is used. Results show that the algorithm is well competent for optimal allocation of reactive power under practical constraints and price based conditions.

• Information Systems Review
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• v.7 no.1
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• pp.21-40
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• 2005

IT investment is continuously increasing. Its outcome, however, is not accomplished as easily as originally expected. There have a variety of efforts to overcome this dilemma. In public sector, information resource management (IRM) was suggested as one of the most effective approach for information & IT management. Accordingly, United States has been incorporating the IRM principles into information-related laws since 1980s. However, such efforts were insufficient in Korea. In this study we attempt to compare our information-related laws with United States laws with respect to major components of IRM. Based on this finding, we go one-step further to suggest ways to arrange a new legislation where the IRM would be a foundation for information & IT management.

• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.493-504
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• 2011

The present paper presents a genetic algorithm (GA) to maximize social welfare and perform congestion management by optimally placing and sizing one Thyristor-Controlled Series Capacitor (TCSC) device in a double-sided auction market. Simulation results, with line flow constraints before and after the compensation, are compared through the Sequential Quadratic Programming SQP method, and are used to analyze the effect of TCSC on the congestion levels of modified IEEE 14-bus and 30-bus test systems. Quadratic, smooth and nonsmooth (with sine components due to valve point loading effect) generator cost curves, and quadratic smooth consumer benefit functions are considered. The main aims of the present study are the inclusion of customer benefit in the social welfare maximization and congestion management objective function, the consideration of nonsmooth generator characteristics, and the optimal locating and sizing of the TCSC using real code-based GA to guarantee fast convergence to the best solution.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.95-96
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• 2006

A variety of systems have been attempted for effective urban management. In this paper, we introduce integrated urban management system (IUMS), which mainly consists of optical line terminal (OLT), optical network terminal (ONTs) and wireless access points (APs), by combining passive optical network (PON) and radio over fiber (RoF) technologies so as to take advantages of both two systems. Further, several IUMS services including disaster detection and prevention system (DDPS), bus information system (BIS) and real time location system (RTLS) are demonstrated in order to employ IUMS for the realization of future ubiquitous city (U-city).

• Industrial Engineering and Management Systems
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• v.2 no.1
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• pp.63-70
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• 2003

In this study, we employed an arithmetic process (AP) approach to resolve gearbox maintenance problems. The approach is realistic and direct in modelling the characteristics of a deteriorating system such as a gearbox since a decreasing AP can model a gearbox's successive operating times and an increasing AP can model the corresponding consecutive repair times. First of all, two test statistics were used to check whether the process is arithmetic or not. Next, model parameters of the AP were estimated using the simple linear regression method. Finally, the optimal replacement policy based on minimising the long-run average cost per day was determined for each type of gearbox.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.33-43
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• 2015

Modern systems development becomes more and more complicated due to the need on the ever-increasing capability of the systems. In addition to the complexity issue, safety concern is also increasing since the malfunctions of the systems under development may result in the accidents in both the test and evaluation phase and the operation phase. Light rail transit(LRT) with passenger capacity between bus and subway is driven by an unmanned control, so safety issues of LRT in emergency shall be considered more carefully than other rolling stock. Modern railway system is a complex system and many actions in emergency are required. In this view, interoperability approach is effective to identify the related elements in emergency. In this paper, we propose the method to generate the fire response scenario of unmann ed LRT based on the outputs of systems engineering architecture design methodology. The proposed method is could be contributed to establish more reliable and applicable fire response scenario.