• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.4
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• pp.31-38
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• 2021

In this paper, we proposed an optimal design for determining the shape of a lifting lug freely by applying a multivariate function to the D-type lug, which is commonly used in shipyards. We derived the optimal aspect ratio of the lug through structural analysis and analyzed the safety and behavior of the lug aspect ratio. As a result, two types of final candidates, both lighter than the existing lug weight, were suitable for the ratio. They were found to have the greatest force at an angle of 45 degrees when a load of 100 tons was imposed. When the horizontal and vertical feature ratio of the lug was 1:3, it showed excellent results in terms of safety rates while maintaining weight reduction and functional aspects.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.5
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• pp.431-438
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• 2012

The representative risk evaluation techniques of the marine traffic environment are the FSA, PAWSA, & IWRAP. For the development of these techniques, the risk factors suitable to the marine traffic environment should be selected & the assessment criterion of the risk factors should be provided. The risk factors were selected as the factors that relate both to the frequency of casualty & to the consequence of casualty because the risk was defined as the frequency of casualty times the consequence of that casualty on the existing techniques. But, the risk factors relate to the consequence of casualty are excluded because the risk is defined as the sum of the risk factors including the frequency and the consequence by factors on this study. The 20 kinds of risk factors to compose the risk are selected and classified into 5 categories according to similar nature through the analysis of preceding study on the classification of the risk factors. Finally, as the foundation of risk assessment model's development for domestic marine traffic environment, the practical assessment criterion of the risk factors are suggested.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.75-92
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• 2007

This article is to investigate the development of seamanship and the art of ship building, marine environment, Silk Road through the sea, and spice exchange at the trade growth of Song Dynasty. For better understanding marine environments, I exemplified what goes before such essential factors as experience and skills in maritime activities. I also demonstrated that South Song Dynasty's abundant economic strength and foreign opening strategy had been supervised systematically through the trade management organization and noted that the nation's overseas exchange had made great effects on its society. The import of the perfume provided the cause where the western influence occupies the orient in the same time when it is a keychains of the orient and the western interchange. For this reason, perfume, which once contributed 1/20 of the revenue, enlarged its portion to 1/10 of the revenue. This indicates the influence of perfume on the national finance in the Song period.

• Nuclear Engineering and Technology
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• v.18 no.1
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• pp.17-26
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• 1986

A test is made for a method to determine reliable bias in the criticality safety analysis of spent fuel storage pool with turnup credit between the reference and rack criticality calculation methods. The spent fuel pool of Kori Unit 1 is conceptually redesigned to the most compact rack with turnup credit, and its multiplication factors are calculated depending on fuel enrichment and burnup, by the Monte Carlo code KENO-IV as a reference and by a two-dimensional collision probability code FATAC as a practical method. Then, the computed values with the help of the above two computer codes are compared to evaluate the bias and its trend in terms of multiplication factor on fuel enrichment and turnup. The result indicates that the bias can be determined with reliability basis but without any disadvantage in criticality safety margin compared with the conventional method.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.3
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• pp.213-227
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• 2013

It is essential to prepare the decommissioning plan for a nuclear power plant (NPP) for the safe decommissioning of the NPP, minimization of the generation of decommissioning wastes, and protection of human beings and environment. Although Kori unit 1 and Wolsong unit 1 will be destined to their decommissioning in Korea in the near future. there is no provisons about preparing the decommissioning plan. In this paper, therefore, the draft guidelines of the decommissioning plan for a NPP were developed by considering the domestic situation, based on the comparative analyses of the regulatory guidelines of the decommissioning plan in U.S., U.K. and France. The draft guidelines are expected to play an important role to modify the domestic laws and regulations on the decommissioning of the NPP, and to give a license holder in charge of decommissioning the detailed instructions for preparing it in advance.

• Nuclear Engineering and Technology
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• v.14 no.2
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• pp.86-91
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• 1982

In 1977, spent fuel storage capacity of Ko-Ri Unit 1 was raised to contain 4-2/3 core, by reducing the center-to-center spacing between fuel assemblies from 53.34cm to 36cm. In this paper the adequacy is discussed in detail by examining the previous design analysis report. According to the analytic method presented by Core Performance Branch, study on credible abnormal moderator density condition is performed by using KENO-IV for the redesigned spent fuel storage facility. Result shows that 36cm for the center-to-center spacing between fuel assemblies is not enough to keep the storage safe at water density of 0.1143g/㎤, which gives the maximum $K_{eff}$ 0.9958$\pm$0.0048, which exceeds the CPB regulation limit 0.98. From sensitivity study regarding to the center-to-center spacing, it should be maintained to space greater than 43cm in order to meet the CPB requirements.s.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.480-480
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• 2021

본 연구에서는 도시재생지역의 재난재해 위험성 및 회복성 분석과 현황 분석을 위한 기초 데이터의 관리와 활용성 증대를 목적으로 데이터를 등록하고 다운로드 할 수 있는 공유 플랫폼을 개발하고자 하였다. 도시재생 데이터 플랫폼은 재난재해, 지역현황, 문서 항목으로 구분하여 도시재생 정보를 서비스한다. 재난재해 항목은 폭우, 폭설, 폭염, 강풍, 지진 5개 자연재해 유형과 이로 인해 추가 피해가 발생할 수 있는 화재, 붕괴, 폭발 사회재난 3개 유형으로 구성되어있으며, 총8 종류의 재난재해 유형에 대한 위험성과 회복성 분석 DB를 제공한다. 지역현황 정보에서는 유휴공간 및 지역자산정보 등 도시재생 현황분석에 필요한 행정(통계)데이터, 시설물정보 등을 제공한다. 아울러 본 연구를 통해 산출되는 논문 및 보고서 등을 문서 항목에서 서비스한다. 데이터셋 등록 시, 시스템에 설정된 재난재해 유형, 시설물 등을 선택해 카테고리를 분류하고, 이력관리를 목적으로 데이터명과 생산년월 등에 대한 필수항목을 입력해야만 등록이 가능하도록 설정하였다. 또한 GIS 기반 공간자료 등록 시에는 가시화 서비스를 위하여 공간자료의 포맷과 좌표체계, 생산년월, 생산기관 등을 필수 입력하도록 하였으며, GIS tool을 활용한 자료 분석에 어려움이 없도록 하였다. 쇠퇴지역의 재난재해 대비/대응을 위한 도시재생 데이터 플랫폼은 금년 시범운영 후, 차년에는 클라우드 서비스 기능을 탑재해 계정 권한과 장소에 제약을 받지 않고 도시재생 업무를 수행하는 모든 사용자가 재난재해 정보를 비롯한 도시재생 관련 정보를 수집·활용할 수 있는 데이터 공유의 장을 구현함으로써 도시재생지역의 효과적인 재난재해 대비/대응 체계를 마련하고자 하였다.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.5
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• pp.389-397
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• 1998

For an effective and efficient management of large amounts of preservice/inservice inspection(PSI/ISI) data in nuclear power plants, an intellegent Windows 95-based data management program was developed. This program enables the prompt extraction of previously conducted PSI/ISI conditions and results so that the time-consuming data management, painstaking data processing and analysis in the past are avoided. The program extracts, and the associated remedies. Furthermore, additional inspection data and comments can be easily added or deleted for subsequent PSI/ISI operation. Although the initial version of the program was applied to Kori nuclear power plant, this program can be equally applied to other nuclear power plant. And also this program can be used to offer the fundamental data for application of evaluation data related to fracture mechanics analysis(FMA), probabilistic reliability assessment(PRA) of PSI/ISI results, performance demonstration initiative(PDI) and risk-informed ISI based on probability of detection(POD) information of ultrasonic examination. Besides, the program can be further developed as a unique PSI/ISI data management expert system that can be apart of PSI/ISI data management expert system that can be a part of PSI/ISI Total Support System(TSS) for Korean nuclear power plants.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.90-90
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• 2017

생력화를 위한 구기자의 수확 기계화는 열악한 수확작업환경을 쾌적한 작업환경으로 개선하고 노동력 감소, 생산비 절감을 할 수 있다. 관행 손 수확과 진동 고리형 수확기 방법보다 높은 작업 능률 향상으로 영농규모의 확대 촉진 및 안정적인 영농 구조를 구축하여 재배농가의 생산비를 절감하여 경쟁력을 높일 수 있으며, 기존 인력에 의존하였던 수확작업을 기계화함으로서 전업농 및 대단위 경작이 가능하게 함으로서 국내에서 생산한 양질의 구기자를 국민에게 안정적으로 제공할 수 있다. 따라서, 본 연구는 구기자 수확작업의 생력화를 위하여 개발 보급된 수목형의 재배법 특성을 분석하고 이를 토대로 타격장치를 적용한 보행형 구기자 수확기를 개발하는데 목적이 있다. 수목형 구기자나무의 분지에 착과되어 있는 숙과를 주행하면서 탈과 할 수 있는 탈과 장치를 제작하기 위하여 타격형 탈과 장치를 3D 모델링 작업(Inventor V.11, Autodesk, USA) 후 시작기를 제작, 구기자 수확 시작기는 주행부, 타격장치, 집과부, 분지유인부로 구성하였다. 구기자 수확 시작기의 최대 높이는 형태학적 특성을 토대로 타격봉의 높이를 900 mm 이하로 제한하였으며, 조향장치의 높이는 800 mm로 하였다. 주행부는 구기자 재식 조사결과를 이용하여 고랑 폭 1,500 mm 이하에서 자유롭게 전 후진 이동이 가능하고 경사로 등을 주행 시에도 안전성을 높이기 위해 자동브레이크 기능이 있으며 타격장치의 타격 봉은 알루미늄 재질로 지름 100 mm, 길이 400 mm로 설계 제작하였으며, 구기자 분지 타격 시 분지와 타격 봉이 수직 상태로 타격이 가능하도록 제작, 집과장치는 포장의 두둑, 고랑은 일괄 표준화가 되어 있지않아 청양구기자시험장에서 측정한 재배법을 바탕으로 설계된 수집부 프레임의 적용범위는 폭 450 mm, 길이 720 mm, 높이 1,500 mm를 집과 범위로 하여 설계 제작하였다. 타격 방식을 적용한 구기자 수확기 성능평가 결과 조숙기에 30초 이상의 탈과 시 87.5 % 이상 탈과는 어려울 것으로 판단되었으며, 성숙기에는 타격시간에 관계없이 92 %의 매우 우수한 탈과율이 나타났다. 성숙기의 주행속도 48 m/h 일 때 탈과율과 집과율은 89 %, 92 %로 나타났다.단위작업시간당 최대 수확 능력은 관행작업 2.9 kg/hr, 진동고리형 수확기 5.2 kg/hr, 타격방식을 적용한 구기자 수확기는 최소 7.6 kg/hr, 최대 24.1 kg/hr로 관행작업과 비교하여 주행속도와 시기별 최소 2.6배, 최대 8.3배의 작업 성능 차이가 나타났다. 재배양식에서는 기계화 수목형이 적합한 것으로 나타났고, 타격방식을 적용한 보행형 구기자 수확기를 이용하여 수형별 시간대별 수확성능을 시험한 결과 우수한 결과가 나타났다. 이에 따라 구기자 재배 농가에 기계화수목형 재배법을 보급하고 타격방식을 적용한 구기자 수확기를 이용하면 작업환경 개선과 노동력, 인건비 절감을 통한 영농규모의 확대 촉진 및 안정적인 영농 구조로 구기자 경쟁력 제고를 할 수 있을 것으로 판단되어진다.

• Journal of Energy Engineering
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• v.29 no.1
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• pp.63-74
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• 2020

The Kori-Unit 1 nuclear power plant, which is scheduled for decommissioning after permanent shutdown, is expected to generate a large amount of various types of radioactive waste during decommissioning process. For concrete radioactive waste, which is expected to occupy the most amount, it is important to analyze the current waste disposal status and legal limitations and to prepare an appropriate and efficient disposal method. Concrete radioactive waste is waste of various levels, of which the clearance level is bioshield concrete. In this paper, clearance radioactive waste safety evaluation was performed using the RESRAD code, which is a safety evaluation code, based on the activation evaluation results for the wastes with the clearance level. The clearance scenario of the target radioactive waste was selected and the individual's exposure dose was calculated at the time of clearance to determine whether the clearance criteria limit prescribed by the Nuclear Safety Act was satisfied. As a result of the evaluation, the results showed significantly lower results and satisfied the criteria value. Based on the results of this clearance safety assessment, the appropriate disposal method for bioshield concrete, which are the clearance wastes of subject of deregulation, was suggested.