• International Area Studies Review
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• 제14권1호
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• pp.3-29
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• 2010

The purpose of this paper is to examine the transmission of domestic and foreign real and monetary disturbances into a small country with heavy imports of intermediate goods, and to analyze how the wage indexation in a small country affects the transmission of foreign disturbances into a small country. We consider the two countries, a small country and the rest of the world, two goods, and rational expectations world model under flexible exchange rate system with perfect capital mobility. We find out that foreign disturbances are transmitted into a small country through the price channel, the foreign output multiplier channel, and the nominal interest rate channel, and the foreign real balance channel. We have conducted an empirical investigation by using the Korean data for a small country and the U.S. data for a large country to see how real and monetary disturbances originating from the US affects the Korean economy with wage indexation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1355-1359
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• 2004

The two way subscriber transmission systems have tendency to spread its carrier frequency bandwidth or information bit rate and average bit error rate according to popularization of high speed information through the digital communication system, transmission medium and the Internet. This fact is an important incentive to realize new systems. These two way subscriber transmission systems usually use same cable or same carrier frequency bandwidth for up stream channel and down stream channel. In the systems, the disturbances of noise, crosstalk or fading affect the characteristics. Specifically, these disturbances cause the decrease of information bit rate and degradation of transmission quality. This paper proposes the improved method of their degradations using the particular feature of two way subscriber transmission systems and it makes clear proposed method is effective by theoretically and some numerical examples.

• International Area Studies Review
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• 제15권1호
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• pp.31-58
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• 2011

The purpose of this paper is to analyze the effects of real and monetary disturbances and economic interactions between two large countries, and to examine how wage indexation affects the transmission of real and monetary disturbances and affects the fiscal and monetary policies of a large country. A two large country model is built, and is theoretically analyzed. We conducted an empirical investigation to apply theoretical findings to the Japanese and US economic interactions in response to real and monetary disturbances originating in one or the other country. Empirical evidence on Japan-USA economic interactions shows that Japan is much more affected by the US economic policy than the USA is affected by the Japanese economic policy. The economic impacts of real and monetary disturbances on the Japanese and US economies are smaller when the Japanese and US wage indexing parameters are lower.

• Transactions of the Korean Society of Mechanical Engineers
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• 제17권8호
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• pp.2023-2032
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• 1993

This study suggests a new type shaft generating system driven by hydrostatic transmission suitable for small size vessels. Since the shaft generating system is affected ceaselessly by disturbances such as speed variation in pump driving speed and variation in external load, a robust servo control must be implemented to obtain stable electric power with constant frequency. Thus, in this study, a digital robust servo control algorithm is applied to the controller design. By the experiment and the numerical computation, the frequency variation characteristics of the generating system under various disturbances are investigated. Conclusively, it is said that the shaft generating system proposed in this study shows excellent control performances.

• Journal of Power Electronics
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• 제1권2호
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• pp.65-70
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• 2001

Transmission System Operators are governed by operational security standards that are applied in real time. During system disturbances, the System Operators must rely on the installed protection and control equipment, prior to human intervention. New power electronic solutions bring rapid and repeatable responses to disturbances, which will help System Operators to guarantee a stable system. Last year, Alstom completed the world's first competitively bid STATCOM to support the voltage on National Grid's 400kV network that supplies London and the Southeast from the north of the UK. It is rated ${\pm}75MVAr$ and forms part of a Static Var System (SVS) with a total rating of 0 to 225MVAr. This paper will describe the reasons for its size, location, its chain-link configuration and give examples of its operating performance. The paper will also describe the features that allow this STATCOM to deliver much more than reactive compensation in support of a wider transmission service objective, as system conditions require.

• Journal of the Korean Society for Precision Engineering
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• 제29권4호
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• pp.373-379
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• 2012

Disruptions in manufacturing systems caused by system changes and disturbances such as the tool wear, machine breakdown, malfunction of transporter, and so on, reduce the productivity and the increase of downtime and manufacturing cost. In order to cope with these challenges, a new method to build an intelligent manufacturing system with biological principles, namely an ant colony inspired manufacturing system, is presented. In the developed system, the manufacturing system is considered as a swarm of cognitive agents where work-pieces, machines and transporters are controlled by the corresponding cognitive agent. The system reacts to disturbances autonomously based on the algorithm of each autonomous entity or the cooperation with them. To develop the ant colony inspired manufacturing system, the disturbances happened in the machining shop of a transmission case were analyzed to classify them and to find out the corresponding management methods. The system architecture with the autonomous characteristics was generated with the cognitive agent and the ant colony technology. A test bed was implemented to prove the functionality of the developed system.

• International journal of advanced smart convergence
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• 제7권4호
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• pp.197-205
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• 2018

Nowadays, wireless sensor networks (WSNs) have been widely adopted in structural health monitoring (SHM) systems for social overhead capital (SOC) public infrastructures. Structural health information, environmental disturbances and sudden changes of weather conditions, damage detections, and external load quantizing are among the capabilities required of SHM systems. These information requires an efficient transmission with which an efficient mobility management support for wireless networks can provide. This paper deals with the analysis of mobility management schemes in order to address the real-time requirement of data traffic delivery for critical SHM information. The host-based and network-based mobility management protocols have been identified and the advantages of network mobility (NEMO) enabled Proxy Mobile Internet Protocol version 6 (PMIPv6) have been leveraged in order to address the SHM information transmission needs. The scheme allows an efficient information transmission as it improves the handover performance due to shortened handover latency as well as reduced signaling overhead.

• The Transactions of the Korean Institute of Electrical Engineers A
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• 제52권5호
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• pp.271-278
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• 2003

Power system stability is correlated with system structure, disturbances and operating conditions, and power flows on transmission lines are closely related with those conditions. This paper proposes a methodology to identify correlative power flows for power system transient and small-signal stability prediction. In transient stability sense, the Critical Clearing Time is used to select some dominant contingencies, and Transient Stability Prediction index is proposed for the quantitative comparison. For small-signal stability, this paper discusses a methodology to identify crucial transmission lines for stability Prediction by introducing a sensitivity factor based on eigenvalue sensitivity technique. On-line monitoring of the selected lines enables to predict system stability in real-time. Also, a Procedure to make a priority list of monitored transmission lines is proposed. The procedure is applied to a test system and the KEPCO systems in the year of 2003 and it shows capabilities of the proposed method

• Proceedings of the KIEE Conference
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• 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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• pp.3-6
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• 2001

Power system stability is correlated with system structure, disturbances and operating conditions. and power flows in transmission lines are closely related with those conditions. This paper discusses a methodology to identify crucial transmission lines for stability diagnosis with respect to transient stability and small-signal stability. On-line monitoring of the selected lines enables to predict system stability in real-time. Also, a Procedure to make a priority list of monitored transmission lines using contingency analysis. The procedure is applied to the PSS/E test system. and it shows capabilities of the proposed method.

• KIEE International Transactions on Power Engineering
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• 제11A권4호
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• pp.15-20
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• 2001

Power system stability is correlated with system structure, disturbances and operating conditions, and power flows on transmission lines are closely related with those conditions. This paper proposes a methodology to identify correlative power flows for power system transient and small-signal stability prediction. In transient stability sense, the Critical Clearing Time is used to select some dominant contingencies, and Transient Stability Prediction index is proposed for the quantitative comparison. For small-signal stability discusses a methodology to identify crucial transmission lines for stability prediction by introducing a sensitivity factor based on eigenvalue sensitivity technique. On-line monitoring of the selected lines enables to predict system stability in real-time. Also, a procedure to make a priority list of monitored transmission lines is proposed. The procedure is applied to a test system, and it shows capabilities of the proposed method.