• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.322-326
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• 2003

In this paper, we establish a new robust $H_{\infty}$ performance condition for uncertain discrete-time systems with convex polytopic uncertainties. We express the condition as a set of linear matrix inequalities (LMIs), which are used to check stability and $H_{\infty}$ disturbance attenuation level by a parameter-dependent Lyapunov matrix. We show that the new condition provides less conservative result than the existing ones which use single Lyapunov matrix. We also show that the robust $H_{\infty}$ state feedback design problem for such uncertain discrete-time systems can be easily dealt with using the approach. The key point in this paper is to propose a kind of decoupling between the Lyapunov matrix and the system matrices in the parameter-dependent matrix inequality by introducing one new matrix variable.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.360-365
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• 1993

In this paper, we propose a new design procedure of the Robust Model Matching(RM) using the Normalized Left Coprime Factorization (NLCF) approach. The RMM aims at reducing the sensitivity of a given control system, but standard design procedures are not for robust stability. Therefore we try applying the robust stability condition based on NLCF to RMM procedure. We first formulate the RMM using the robust stability condition of NLCF approach, then we propose the new procedure of the RMM. The point is that the condition includes the measure of sensitivity of the RMM. In the proposed procedure, a cost function is determined through the condition and solved by H$_{\infty}$ contro technique. Finally we show a design example and check the performance..

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.1
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• pp.8-13
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• 2010

Many vehicles have significantly under-inflated tires, primarily because drivers infrequently check their vehicles' tire pressure. When a tire is used while significantly under-inflated, its sidewalls flex more and the tire temperature increases, increasing stress and the risk of failure. In this study we evaluated tire safety and economical efficiency at various inflation pressure. For tire safety we performed FMVSS indoor durability test, measurement of rolling tire temperature, braking performance at dry/wet road condition, and rolling resistance test for economical efficiency. Results show that low pressure decreases tire durability of both speed-increase condition and load-increase condition. Heat temperature of rolling tire increases as pressure decreases and significantly under-inflated tires cause increase of vehicle's stopping distance at wet road condition. Also Under-inflation increases the rolling resistance of a tire and, correspondingly, decreases vehicle's fuel economy.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.11
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• pp.1-6
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• 2002

This study is about optimization of Laser Repair Condition in EDS Line to improve AC and DC characteristic of high speed DRAM. The margin of AC parameter can be improved by forcing the proper DC generator levels and also improved by cutting the optional fuse about characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.478-479
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• 2007

With increasing interest in the reduction of cost for operation and maintenance of overhead catenary system, various methods of condition monitoring have been developed. In this paper, we proposed network-based telemetry system for condition monitoring in railway and acquired data from any kind of sensor in catenary line and structure at high voltage. This development gives the solution for online condition monitoring in railway. To check the validity of our approach in terms of application, we realized network-based telemetry System.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.4
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• pp.701-713
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• 2021

Race Condition is a vulnerability in which two or more processes input or manipulate a common resource at the same time, resulting in unintended results. This vulnerability can lead to problems such as denial of service, elevation of privilege. When a vulnerability occurs in software, the relevant information is documented, but often the cause of the vulnerability or the source code is not disclosed. In this case, analysis at the binary level is necessary to detect the vulnerability. This paper aims to detect the Time-Of-Check Time-Of-Use (TOCTOU) Race Condition vulnerability of UNIX kernel-based File System at the binary level. So far, various detection techniques of static/dynamic analysis techniques have been studied for the vulnerability. Existing vulnerability detection tools using static analysis detect through source code analysis, and there are currently few studies conducted at the binary level. In this paper, we propose a method for detecting TOCTOU Race Condition in File System based on Control Flow Graph and Call Graph through Binary Analysis Platform (BAP), a binary static analysis tool.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.993-997
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• 2004

A data error inspection algorithm for wireless digital data communication was developed. Original data converted By wireless digital data error inspection algorithm. Wireless digital data is high possibility to get distortion and lose by noise and barrier on wireless. If the data check damaged and lost at receiver, can't make it clear and can't judge whether this data is right or not. Therefore, by wireless transmission data need the data error inspection algorithm in order to decrease the data distortion and lose and to monitoring the transmission data as real time. This study consists of RF station for wireless transmission, Water Level Meter station for water level measurement and Error inspection algorithm for error check of transmission data. This study is also that investigation and search for error inspection algorithm in order to wireless digital data transmission in condition of the least data's damage and lose. Designed transmitter and receiver with one - chip micro process to protect to swell the volume of circuit. Had designed RF transmitter - receiver station simply by means of ATMEL one - chip micro processing the systems. Used 10mW of the best RF power and 448MHz-449MHz on frequency band which is open to public touse free within the limited power.

• Journal of Sericultural and Entomological Science
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• v.42 no.1
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• pp.24-27
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• 2000

A new silkworm variety 'Yangwonjam'for both of spring and autumn rearing season is F$_1$hybrid between Jam 143, a Japanese race bred from H5R1/P8503 and Jam 144, a Chinese race from M8312/8190. This is the first both parent sex-limited larval marking variety in Korea, and which contributes to eggs production of F$_1$hybrid silkworm with saving labor. Jam 143, Japanese parent of the 'Yangwonjam'showed high GCA in pupation percentage and Jam 144, Chinese parent showed high GCA in pupation percentage and single cocoon weight. In the local adaptability test performed at 8 local areas in spring of 1998, Yangwonjam records 1% higher in pupation percentage and 5%, 4% lower in single cocoon weight, cocoon yield from 10,000 3rd molted larvae respectively than the check variety Kumokjam. Also in the resistance test against unfavorable rearing condition performed in spring of 1997, Yangwonjam records 9%, 14% lower in single cocoon weight, cocoon shell weight respectively than the check variety, but showed 1% higher in pupation percentage than check variety.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.1C
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• pp.14-19
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• 2006

The high encoding complexity of LDPC codes can be solved by designing structured parity-check matrix. If the parity-check matrix of LDPC codes is composed of same type of blocks, decoder implementation can be simple, this structure allow structured decoding and required memory for storing the parity-check matrix can be reduced largely. In this parer, we propose a construction algorithm for short block length structured LDPC codes based on girth condition, PEG algorithm and variable node connectivity. The code designed by this algorithm shows similar performance to other codes without structured constraint in low SNR and better performance in high SNR than those by simulation

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.256-258
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• 2016

Domestic vehicle demand is growing steadily. In proportion to the increased interest generated by the automobile-related accidents are more frequent. One of the causes of these accidents are caused by vehicle accidents exists tire problems. Users check tire wear with their naked eyes or check the tread and the wear indicator by using a coin. However, such visual judgment cannot be precise and make it possible to identify the time for tire replacement. Therefore, by utilizing visual and objective data rather than incorrect decisions through objective data, we designed a system that accurately and can easily tell whether the tire condition and replacement of the driver.