• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2862-2867
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• 2008

High-temperature components of gas turbine operated for certain period of time can be reused by being repaired or rejuvenated. In case of the gas turbine combustion liners, the biggest and the most important one in the high-temperature components, come in a repair shop after operated for 8,000 or 12,000 hours according to the model and go through the repair and rejuvenation in order to be reused. A stated combustion liner is the first channel which has the combustion gas reached a nozzle from a fuel nozzle. Materials and coating properties of old and new model combustion liners were investigated. To repair these components after the visual inspection, the coatings of combustion liners were removed and then FPI(Fluorescent Penetrant Inspection), a kind of the NDI(Non-Destructive Inspection), was conducted. Damage patterns and the number of the damaged components were classified and analyzed based on data provided from the visual inspection over a long period of time. Focusing on the difference between old model and new model combustion liners, we analyzed the damage distribution and changes and consequently concluded that new model combustion liner would increase repair rate.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1864-1870
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• 2007

The inspection periods for the metro EMU maintenances vary variously according to the countries and railway operators. And the inspection systems vary according to the safety, economical, technical aspects, and also the social environments like passengers and maintenance qualities, etc. Also, in economic point of view, maintenance requires the man power, facilities, equipments, purchasing of parts and the loss of not being in revenue service during the maintenance period. Recently, there is a tendency that the inspection periods are extended gradually owing to the increased reliabilities of the equipments and parts of EMUs. Even if it is the EMUs that are already be in service, once the inspection method is innovated, the inspection time can be reduced. The inspection management innovation scheme includes such methods as the complete module to module replacement when trouble shooting a faulty parts before putting the EMU back to revenue service, the replacements of parts in complete set unit for the heavy maintenance, the establishments of exchange periods for the wasting parts, modernization of inspection equipments, introduction of RAMS for the reliability improvement and computerization of EMU maintenance management, etc. I think it is possible to optimize the inspection scopes and periods per parts and equipments by the introduction of RAMS.

• 한국압력기기공학회 논문집
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• 제14권2호
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• pp.49-58
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• 2018

The regulatory periodic inspection program (PSI) conducted at every overhaul period is the most important process for confirming the safety of nuclear power plants. The PSI for operating nuclear power plants in Korea mainly consist of component level performance check that had been developed based on deterministic approach putting the same degree of importance to all the inspection items. This inspection methodology is likely to be effective for preoperational inspection. However, once the plant is put into service, the PSI must be focused on whether to minimize the risk of accident using defense-in-depth concept and risk insight. The incorporation of defense-in-depth concept and risk insight into the deterministic based safety inspection has not been well studied so far. In this study, two track approaches are proposed to make sure that core damage be avoided: one is to secure success path and the other to block the failure path in a specific event tree of PSA. The investigation shows how to select safety important components and how to set up inspection group to ensure that core damage would not occur for a given initiating event, which results in strengthening defense-in-depth level 3.

• 한국국방경영분석학회지
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• 제30권2호
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• pp.108-121
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• 2004

This paper deals with a procedure of changing the current inspection & replacement periods for ROKAF aircraft parts. ROKAF is mostly operating aircraft of foreign makes, and takes maintenance actions according to Technical Orders(TO.) published by foreign aircraft manufacturers. Therefore ROKAF inspects and replaces specific parts at the time noticed from T.O.. These inspection and replacement periods are determined by manufacturers according to the standard operating environment and parts' durability. But the standard operating environment Is different from operator's environment. Because of this difference, the inspection and replacement periods have to be changed according to operators' operation environment. It is resonable that the manufacturer, having design materials and life test data of parts, changes those periods together with materials of operators' operation environment. But we have many difficulties in obtaining the design materials and life test data. Then this paper proposes a procedure of changing the periods of aircraft's parts with life data obtained during operating aircraft. For the reliability analysis, a software of RELEST (Reliability Estimation Version 1.0) is used.

• 한국국방경영분석학회지
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• 제18권1호
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• pp.110-127
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• 1992

In the preventive replacement policies of system that the failure can be detected through only periodic inspection, there is a penalty cost associated with the lapsed time between system failure and its detection. The system under study is replaced if the system fails before $n^{th}$ inspection, otherwise, preventive replacement is performed at the $n^{th}$ inspection. The decision variables are the inspection interval and the period of preventive replacement. This study presents the optimal preventive replacement policy that minimizes the long-run expected cost per unit time.

• 한국구조물진단유지관리공학회 논문집
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• 제14권6호
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• pp.93-99
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• 2010

본 논문에서는 상부구조에 있어서 보-기둥 강성비 변화에 따른 골조의 특성과 상부구조와 면진층 간의 진동주기비에 따른 면진효과를 분석해 보고, 상부골조의 주기와 목표 면진주기의 설정에 따라 면진효과가 어떻게 달라지는가에 대한 정보를 제공하여 향후 면진건물을 설계하기 위한 기본계획을 세우는데 있어서 필요한 기초 자료를 제공하고자 한다. 그 결과 건물골조의 경우 유효한 면진효과를 얻기 위해서는 최소한 상부구조의 고유진동주기 대비 2.5배 이상의 면진주기를 확보하고, 목표 면진주기를 2.0초 이상으로 설정하여 설계할 것을 추천한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.351-354
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• 2003

To inspect point-defect in LCD pannel, calculate period and eliminated pattern. And then find point-defect to compare block image with each period. First processing, Founded over point defects. To reduce wrong point defect. Next, label point-defects and eliminated not surpass fixed limit-size.

• 한국환경보건학회지
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• 제29권2호
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• pp.87-93
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• 2003

A survey including an inspection was conducted to assess the sanitary condition of kitchens in the school food-service programs and to prepare background data for improving the safety of school meals. The survey was carried out over a two-month period (September-October, 2001). A self-administered questionnaire recommended by the Korea Ministry of Education & Human Resources Development (MOEHRD) was offered to a random sample of dieticians of twenty-five elementary schools in one region of Korea about food, sanitation, and safety inspection of their kitchens. Air temperature, relative humidity, and airborne microbes in the kitchens were monitored during preparation, cooking, and service. The inspection results showed their sanitary rendition met the level B of the recommendation of the Korea MOEHRD. The range of air temperature of the kitchens was 21.4~22.4$^{\circ}C$. and the range of relative humidity was 62.4~69.6%. The microbiological evaluation of kitchen samples indicated aerobic plate count levels from 22..5 to 26.5 CFU/15 minutes. Although the results of inspection show that the levels of sanitary condition of kitchens in the schools were good, they are not satisfactory for safe food-servile because the temperature and humidity levels are high. This study indicates that the school kitchens should be monitored and strict inspection is necessary. The legal standards for school food-service should include standards for kitchen air temperature, relative humidity, and airborne microbes.

• 무역상무연구
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• 제74권
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• pp.1-23
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• 2017

The buyer must examine the goods, or cause them to be examined, within as short a period as is practicable in the circumstances. Article 38 lays down a fundamental principle that requires the buyer to examine quickly the goods delivered by the seller. Article 38 (1) provides that the examination be made within as short a period as practicable in the circumstances. The goods have to be examined within as short a period as is practicable in the circumstances. The rule is based on the fundamental idea of reasonableness, meaning that the buyer must examine the goods as soon as reasonably possible. It may be said that the buyer should act reasonably fast. Article 38 (2), (3) concerns sales involving carriage of the goods, where the seller's obligation to deliver consists in handing the goods over to the first carrier for transmission to the buyer. In this case the buyer is generally able to examine the goods only after they have come to destination. Article 38 (3) takes into account the case where the buyer redirects the goods in transit or re-dispatches them to another destination. Redirection in transit occurs when the destination is changed before the goods are received by the buyer. The buyer could re-dispatch the goods without having them unloaded, or re-dispatch them through another carrier.

• 대한수의사회지
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• 제7권1호
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• pp.4-11
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• 1963

During the period starting November 8th to 26th, 1960, 160 restaurunts located in Seoul area were inspected with special emphasis on the sanitary aspect of food and environment of each restaurant. The inspection was concerned with bacteriological test for