• JOURNAL OF ELECTRICAL WORLD
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• s.268
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• pp.25-29
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• 1999

우리 국민에게 2000년은 야누스의 두 얼굴로 다가오고 있다. 새로운 천년에 대한 희망의 얼굴과, 세기말 대재양론에 Y2K문제까지 가세하여 불안함을 감추지 못하는 절망의 얼굴이다. 일부 종교단체나 예언가들은 Y2K문제로 인해 지구의 종말이 온다고 믿고서 피난처를 만들고 있으며 인터넷망 등을 이용, 지지세력의 확장을 꾀하고 있다. 그러나 우리는 이에 편승하여 인류의 미래를 이들에게 맡길 것이 아니라, Y2K문제의 실상을 정확히 이해하고 지혜로운 대처를 위해 모든 역량을 결집해야 할 것이다. Y2K문제는 개인용 컴퓨터에서부터 금융, 통신, 전력, 행정전산망 등 국가산업 전반에 영향을 미칠 뿐 아니라 모든 국민의 생활과 직결되는 문제이기 때문이다. 특히 안전성이 생명인 원자력 발전소에서의 Y2K문제는 모든 국민과 언론의 집중적인 관심의 대상이 되고 있다. 이 같은 관심과 우려의 표명은 원전의 특성을 고려할 때 당연한 현상이지만, 2000년이 되면 원전이 불시에 정지되고 큰 사고가 발생할 것이라는 일부의 시각은 국민의 불안만 가중시킬 뿐이다. 결론부터 말하자면 이러한 우려는 기우에 불과하다. 예를 들면 은행 전산망에서 이자를 계산할 때는 날짜가 필수적이다. 그러나 일반 산업 자동화 설비와 마찬가지로 24시간 연속 가동되는 원자력발전소를 운전 할 때는 미리 일정한 값으로 입력된 각종 운전자료, 즉 온도, 압력, 유량 등과 매순간 생성되는 운전자료들을 단순 비교하기 때문에 날짜가 필요치 않다. 이는 마치 실내 난방온도를 일정 값으로 미리 정해놓으면, 그때 그때의 실내온도와 미리 정해진 온도를 비교하여 난방기가 자동으로 작동되는 방식과 같다. 따라서 운전과 직접 관련되는 설비는 Y2K와 관련이 없고, 운전 편의를 위한 데이터취득설비 일부와 방사능 계측 등의 측정장비에 Y2K영향이 있다. 한전에서는 이들 문제의 적시 해결을 위해 충분한 예산과 인력을 확보하여 문제를 해결하는 과정에 있으며 3월 현재 약 70$\%$의 공정을 보이고 있다.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.5
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• pp.663-668
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• 2012

A TPMS(Tire Pressure Monitoring System) is a wireless communication system designed to monitor the pressure and temperature of pneumatic tires of a vehicle. In order to provide the aid in protecting a driver, this system reports tire pressure information to the driver of the vehicle. Since the wireless communication technique should be employed to transmit the TPMS data from each tire to signal processing unit in the vehicle, it suffers from interference signals from external electrical or electronics equipments. In this paper, we propose the TPMS interference cancellation technique based on GSC(Generalized Sidelobe Canceler), which does not have only the excellent performance like MVDR(Minimum-Variance-Distortionless-Response) but also has the low computational complexity comparing with MVDR. The performance of interference suppression is conformed by computer simulation examples.

• Journal of the Korean Institute of Gas
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• v.9 no.2 s.27
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• pp.16-21
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• 2005

Functions of the compression ring plate fixed at the concrete side wall are to connect and support the steel roof plate. It should be designed to endure stably all the loads such as weight of steel roof, inner pressure and concrete weight. Behavior of the compression ring during construction has been analyzed by the finite element method and real measured data. Additionally, on the basis of results from parametric study of design variables for the steel roof a more reasonable design method for the compression ring has been proposed.

• Journal of the Korean Institute of Gas
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• v.11 no.4
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• pp.98-103
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• 2007

Likelihood analysis was used for the revision of release probability/frequency in chlorine Injection facilities used in chlorine process. Typically these facilities consist of pressure cylinder, vaporizer, pipeline, measuring equipment and safety equipment. This paper described the incident scenarios considered, likelihood analysis procedure and the selection and application of basic events and for failure rates of mechanical components. Human errors were also considered. The major objective of this paper is to estimate the likelihood of each determined incident scenarios. We estimated failure rates of mechanical components based on likelihood analysis procedure. Human errors were also considered. It was estimated to have $5.73{\times}10^{-5}$ $Cl_2$ leak per year during the major $Cl_2$ handling process. The probability of failure in scrubber system was$4.11{\times}10^{-2}$/demand.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.275-284
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• 1991

Fatigure crack growth from surface defects is one of the most important subjects for the evaluation and the assurance of safety in pressure vessels, piping systems, ship hulls and other various structures. This paper attempts to analysis some practical or general problems such as the estimation of crack growth life to penetrate the plate thickness, based on fatigure crack growth from a single surface flaw and the interaction of multiple flaws. An experiment on the coalescence of multiple undercuts was carried out under cyclic tension condition as a attempt to the analysis of multiple crack problems. It is noted that the fracture strength is characterized by the analogy to that in a single crack growth.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.3
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• pp.80-89
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• 1998

Propulsion subsystem transfers KOMPSAT into mission orbit and controls its attitude. Design factor consists of structure safety, electrical circuit design, consumable power estimation of thermal hardwares, damping device design of fuel transient pressure, and system configuration design by considering plume effect from thruster firing. System level analysis should be performed for verification of system design under launch vehicle and orbital environment. Electrical functional test of thermal control hardware, proof pressure test, cleanliness verification test, and internal/external leakage test of fuel feeding system should be carried out for performance estimation of propulsion system. Design and assembly process of propulsion subsystem was depicted and reliability of system was verified by test analysis in this paper.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.2
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• pp.103-111
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• 2007

Since the 1980's the school of Busan metropolitan city has been converted into the other land-use such as high-rise apartment houses, commercial and office buildings. School facilities are available to locate in green area due to not restricted by land use zone. And the location of school facilities were closely related with the school district, distribution of neighborhood unit, safety of students, and so on. The purpose of this study is to understand the location characteristic of school - moved sites in Busan metropolitan city.

• Journal of the Society of Naval Architects of Korea
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• v.35 no.1
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• pp.80-87
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• 1998

This paper deals with the evaluation of structural safety to fatigue strength of marine propeller blades having high skew angle and operating in irregular wake field. The determination of the optimum skew angle of a propeller blade is one of the important task at the initial design stage especially in the case of high speed vessel such as container ships. A computer program system has been developed to evaluate the structural safety to fatigue strength and has been applied to several propeller blades with varying skew angle within a wide range. In the parametric study the pressure acting on the blade surface is calculated using the non-lineal lifting surface theory and the structural analysis is performed using MSC/NASTRAN. The relationship between skew angle and structural safety to fatigue strength is investigated and this paper ends with describing the optimum skew angle of a propeller blade.

• Journal of Conservation Science
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• v.6 no.1 s.7
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• pp.71-78
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• 1997

Oil painting shows a wide variety of damages due to differentcohesiveness between materials and different responses to temperature and humidity. The deforming flatness of canvas is a major cause of deterioration. The heat, pressure and moisture, and classical materials which had been traditionally used to correct the deformation of supports have caused damages to the paintings. In modern restoration of paintings, new methods have been developed to avoid the use of such potentially harmful elements. In this paper the correcting of deformed support with the use of low-pressure table, deformation correction frame and new materials, which has been developed both to protect the works and to maximize the effect of restoration.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.11 no.1
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• pp.1-6
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• 1999

Nearshore and offshore pipelines are often applied to carry oil, gas, water and combined products. The thermal and pressure gradients of the fluid inside pipeline cause pipeline expansion. This expansion produces stress to connecting structures with pipeline. Should this stress exceeds the yield strength of connecting components or the allowable displacement of the system, a damage can occur. As most pipelines contain hazardous and toxic fluids, the damage usually leads to fatal accidents involving great economic loss as well. Even subsea pipelines can be easily applied to transport liquid type fluid without time and space constraint, they should be designed and maintained carefully to be functional safely during design lifetime. In this paper, various theories estimating pipeline thermal expansion are investigated and the effects of pipe components to expansion are studied.