• 한국양식학회지
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• 제21권4호
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• pp.346-350
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• 2008

Haliotis속 전복류 내에서 종간의 유전적 차이 및 유연관계를 나타내는 유전표식으로 RAPD를 사용하여 그 유용성 정도를 파악하기 위하여 북반구 2종(H. discus hannai와 H. rufescens)과 남반구 2종(H. rubra와 H. midae)을 대상으로 RAPD 분석을 행하였다. 그 결과 RAPD는 Haliotis 종간의 구분은 명확히 구분할 수 있는 유용한 유전표식으로 평가되었으나, 유전적 유연관계에 있어서는 형태학적 및 지리학적 분포에 따른 유연관계와는 상이하게 나타났다.

• 한국정보통신학회논문지
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• 제17권9호
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• pp.2082-2090
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• 2013

상담자의 심리검사에 대한 정보와 자원을 관리하는 재활심리분석시스템은 정보교환의 호환성과 보안 문제를 발생시키고 있다. 이런 문제를 해결하기 위하여 네트워크와 데이터에 대한 접근 투명성을 제공하는 객체지향시스템을 폭넓게 사용되고 있으나 보안을 보장하기 위해 사용하는 메서드와 속성 지향적인 접근제어기법은 저장된 데이타가 방대하고 다수의 사용자가 서비스 요청시 가용성을 제한되고 효과적이지 못하다. 따라서 본 논문에서는 재활심리분석을 위한 데이터베이스시스템에서 접근처리지연과 네트워크 폭주의 해결책으로 보안성과 가용성을 동시에 고려하는 접근제어시스템으로 타입정보를 사용한 객체의 접근제어 모델을 제안하고 이의 검증을 위하여 객체지향 시스템의 접근제어모델과 분리 통합되는 형태로 타입 보안 모델을 구현하였다.

• 센서학회지
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• 제19권6호
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• pp.490-496
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• 2010

In this study, in order to overcome the weakness of acoustic field analysis which is generally used for ultrasonic probe performance evaluation, automatic acoustic field measurement system and evaluation parameters were proposed. The comparisons between acoustic field simulation and measured acoustic distribution data of normal and abnormal channels were conducted to evaluate the availability of proposed system and evaluation parameters. First, the impulse response characteristic of sample probe was investigated to classify the normal elements and abnormal elements. And then, normal channels and abnormal channels with abnormal element were chosen. The suggested 12 evaluation parameters were calculated using the acoustic fields of these channels. The availability of proposed automatic acoustic field measurement system and evaluation parameters was confirmed. And the performance evaluation of ultrasonic probe using acoustic field analysis could be easier and faster.

• 한국인구학
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• 제23권2호
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• pp.143-166
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• 2000

이 연구는 상이한 성선호의 문화적 전통을 지닌 인종집단들을 대상으로 하여 의료수준과 유아사망력의 관계를 파악하기 위한 것이다 이를 위해 1990년 중국인구센서스 중에서 연변자치 주에 거주하는 조선족과 한족 그리고 서쌍판납자치주의 한족과 다이족의 원자료를 활용하였다. 이 논문은 성선호, 사회경제적 수준, 의료수준과 유아의 성별 차별사망력의 관계를 설명하기 위한 새로운 모형을 제시하고 있다. 의료인력이 널리 가용한 지역사회에서는 유아사망력의 수준이 성선호에 의하여 영향받을 가능성이 낮다. 그러나 지역사회의 의료수준이 낮으면, 특정한 성을 선호하는 경향이 강한 인종집단의 구성원들은 선호하는 성의 자녀들의 생존을 위하여 모든 노력을 기울이게 될 것이다. 이에 반해서 부모들이 선호하지 않는 성의 자녀생존을 위한 행위들은 이에 수 반되는 비용이나 여러 가지 조건들에 의하여 영향을 받게될 것이다. 따라서 선호하는 성의 유아사망력의 수준은 선호하지 않는 성의 그것에 비해 월등히 낮을 가능성이 크다. 그러나 사회경제적 발전과정에서 의료수준이 향상되고 이에 수반되는 비용이 낮아지면, 선호하지 않는 성의 유아사망력은 급격히 감소하고 성별 사망력의 차이는 줄어드는 경향을 보이게 된다. 이 연구에서 강한 남아선호관을 지닌 조선족 및 한족과, 반대로 여아를 선호하는 경향이 강한 다이족의 유아사망력을 분석한 결과는 이러한 명제들을 뒷받침 해준다.

• 한국안전학회지
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• 제19권4호
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• pp.55-59
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• 2004

In this study, the required life cycle cost is evaluated in consideration of the equipment's availability during its lift cycle. In order to meet the maximum availability required by the process, the failure cost and life cycle cost is assessed The optimal equipment selection method is presented according to the analysis of the failure cost and life cycle cost. For the systems in which equipments are connected serially, the optimal equipments are selected by minimizing the life cycle cost and satisfying the required system availability goal. In addition, the selection methods and lift cycle cost are analyzed according to the cost variation of the equipment. By using the life cycle evaluation procedure, the failure cost and maintenance cost needed during the life cycle of the equipment can be presented.

• 한국자동차공학회논문집
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• 제7권7호
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• pp.242-249
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• 1999

Spot welding is very important and useful technology in fabrication of an automobile body structure. Because fatigue strength of the spot welding point is however considerably lower than parent metal due to stress concentration at the nugget edge, accurate stress analysis and fatigue stength evaluation of spot welded lap joint are very important to valuate the reliability and durability of automobile body structure and to establish a criterion of long life fatigue design. Many invetigators have studied so far onsystematic fatigue strength evaluation with various methods. It is however necessary to verify their reliability and abailability for practical application to fatigue design of spot welded structure, Thus,in this study, fatigue strength evaluation methods of spot welded lap joint. which are the maximum principal stress method. the fracture and availability with the Weibull probability distribution. From the results, it was found that reliability and availability withe the Weibull probaility distribution. From the results, it was found that reliability and availability of the suggest fatigue strength estimation methods methods were higher than $\Delta$P-$N_f$ relation. However, among them , reliability of the maximum pricipal stress method was the highest.

• 시스템엔지니어링학술지
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• 제10권1호
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• pp.33-41
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• 2014

New design concept of Reactor Coolant System (RCS) including a reactor assembly for the SMR is introduced in this work. An exploration of new type of reactor that is advanced from proposed SMRs is performed by using systems engineering approach. In this point of view project structured on three main phases; needs analysis (NA), concept exploration (CE), and concept definition (CD). Main objectives as an output of the CE stage are a small size, low cost, shortening the schedule, and enhancing safety. The SMRs usually have a small size requirement. In order to meet the size requirement and to achieve a productivity, in other words, easiness to manufacture, this paper suggests an integrated PWR design concept through researching predecessors. Although the integrated PWR concept provides many advantages, it has disadvantages that composite of maintenance and a low availability problem. Therefore, this paper comes up with a run-to-fail design concept based on modular design to address the maintenance problem and to maximize the availability of SMRs as well as to be compatible with the overall-SMRs including Barge Mounted(BM)type.

• 한국IT서비스학회지
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• 제19권3호
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• pp.151-163
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• 2020

This paper describes a study on the FRACAS(Failure Reporting Analysis and Corrective Action System)-based dependability control platform for domestic urban railway trains. There are more demands for the verification of the dependability of trains as it becomes a regulation for train manufacturers to verify the dependability recently. Train manufacturers as well as railway operators need a effective FRACAS solution to perform the verification of the dependability. Yet current FRACAS solutions have limitations to support the verification processes effectively. This paper addresses the issues of current FRACAS solutions and suggests a FRACAS framework designed for the domestic urban railway trains. Service failure scenarios are standardized using the proposed availability model to implement a more user-friendly and reliable platform. A new FRACAS-based platform for the dependability control (SCARF^®) has been developed to implement the suggested framework. The detail interfaces and functions of the platform are explained. The SCARF^® platform is expected to engage the increasing demands for the dependability control successfully enhancing the reliability, maintainability, availability and safety of domestic urban railway trains eventually.

• 대한안전경영과학회지
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• 제14권2호
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• pp.147-158
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• 2012

This paper aims to develop a new chain metrics for obtaining lean Overall Equipment Effectiveness(OEE) and present implementation strategy which considers the properties for Total Productive Maintenance(TPM) to reduce machine losses, Performance Analysis and Control(PAC) to reduce labor losses, Lean Production System(LPS) to reduce floor wastes, and Theory of Constraints(TOC) to minimize the problem of Capacity Constrained Resource(CCR). The study reviews the related literatures and reformulates the structure of machine losses, labor losses and field wastes. The research also develops the integrated productivity metrics according to time, units, reliability and maintainability. It is found that the study develops the actual productivity measure in terms of efficiency, effectiveness and standard productivity. In addition to that, it outlines and develops by using the integrated LPS and TPM, lean OEE measures such as Time Based Productivity(TBP), Unit Based Productivity(UBP), and Reliability & Maintainability Based Availability(RMBA). Implication examples are proposed to make it easier and available for practioners to understand the implementation strategies about TPM OEE, lean OEE and TOC OEE. Futhermore related to other studies, the research contributes to create a new chain productivity measures to clear the interrelationship concepts of productivity, efficiency and effectiveness. Moreover the paper develops the enhanced OEE measures by integration of TPM, PAC, LPS and TOC with the perspective of schedule, throughput, reliability, maintainability and availability.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2004년도 Annual Meeting BioExibition International Symposium
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• pp.236-241
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• 2004

In Escherichia coli, L-lysine biosynthetic pathway is composed of nine enzymatic reactions. It has been well established that most of the lysine biosynthetic genes are regulated by the lysine availability, even though they are all scattered around the chromosome without forming any multigenic operon structure. However, no transcriptional regulatory mechanism has been identified except for the activation of lysA gene by the LysR. In this study, changes in transcriptome profiles of wild type cells and lysR deletion mutant cells grown in the absence or presence of lysine were investigated by using DNA microarray technique. Microarray data analysis revealed three groups of genes whose expression varies depending on the availability of lysine or LysR or both. To further examine the regulatory patterns of lysine biosynthetic genes, lacZ operon fusions were constructed and their expression was measured under various conditions. Obtained results strongly suggest that there is an additional regulatory mechanism which senses the lysine availability and coordinates gene expression.