• 대한방사선기술학회지:방사선기술과학
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• 제37권4호
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• pp.295-305
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• 2014

초음파장비는 인체 병변의 유무를 검사하는 의료장비로서 정확한 의료영상정보를 제공해야 한다. 의료용 초음파장비 성능측정을 위해 초음파팬텀(ATS-539)의 측정방법과 기준으로 대구지역 의료기관의 초음파장비 성능의 실태를 알아보고, 초음파팬텀을 이용한 장비성능검사의 기본 자료를 제시하고자 한다. 초음파팬텀의 측정방법과 기준인 불응영역, 수직거리정확성측정, 수평거리정확성측정, 축방향/측 해상도, 민감도, 회색조 및 동적범위를 사용하였다. 그리고 국소영역, 기능적 해상도를 추가해서 총 8개 항목으로 측정하고 평가하였다. 결과분석을 위해 평균, 표준편차, 빈도 및 백분율을 제시하였고, Mann-Whiney test와 t-test를 실시하였으며, 유의수준은 0.05로 하였다. 본 연구의 결과는 다음과 같다. 1. 초음파팬텀 측정결과는 총 35대 중 합격은 31대 88.6%, 불합격은 4대 11.4%였다. 2. 합격기준이 제시되지 않은 국소영역과 기능적 해상도 4 mm가 통계적으로 유의하게 합격군과 불합격군간의 평균의 차이가 있었다. 3. 불합격한 장비의 평균 사용연수는 7.25년으로 합격한 장비 4.13년보다 차이가 있었다. 대구지역내 임상에 실제 사용되는 의료용 초음파장비의 성능 실태를 파악해 보았고, 합격기준이 제시되지 않은 2항목에 대한 기초자료를 제시하였다. 초음파장비 사용연한이 장비성능과 관계가 있었다. 의료용 초음파장비 성능검사를 위한 초음파팬텀측정은 장비의 최적의 성능 유지를 위하여 제도적인 대책 마련이 필요하다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제7권3호
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• pp.111-118
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• 2007

In 2000, US Army Test and Evaluation Command (ATEC) released the status of reliability requirement levels and achievements for the military equipment which evaluated through the operational tests from 1985 to 1990 and from 1996 to 2000. The rates of military equipments that do not meet reliability requirements are 59% from 1985 to 1990 and 80% from 1996 to 2000. Thus, the US Army has figured out causes, taken steps and put them into practice, This paper is about the recent reliability problems and the latest tendency about US military equipment to acquirere liability level.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.582-585
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• 2011

During disaster response, prioritization of limited resources is one of the most important bust challenging tasks. At the same time, it is imperative to timely provide the rescuers with the adequate equipment to facilitate lifesaving operations. However, supply of high demand equipment was insufficient during the initial phase of disaster response, challenging lifesaving operations in the case of the 9-11 terrorist attacks. In respond to the Haiti Earthquake, spatial information of the geographic area was not sufficient to support the search and rescue operations in the early phase of disaster response. However, with the help of civilians, information such as road names, infrastructure damage, and victim locations were updated into the spatial data repository. At the same time, resource outside of the disaster affected zone converges into the area to assist the response efforts, which is the effect of convergence that often made resource coordination challenging in large scale disasters. To efficiently collect information and utilize the converging resources, this paper proposes a flexible data repository for information update for equipment utilization in large scale disaster response scenarios.

• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1363-1373
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• 2022

The recent seismic events that occurred in South Korea have increased the interest in the re-evaluation of the seismic capacity of nuclear power plant (NPP) equipment, which is often conservatively estimated. To date, various approaches-including the Bayesian method proposed by the United States (US) Electric Power Research Institute -have been developed to quantify the seismic capacity of NPP equipment. Among these, the Bayesian approach has advantages in accounting for both prior knowledge and new information to update the probabilistic distribution of seismic capacity. However, data availability and region-specific issues exist in applying this Bayesian approach to Korean NPP equipment. Therefore, this paper proposes to construct an earthquake experience database by combining available earthquake records at Korean NPP sites and the general location of equipment within NPPs. Also, for the better representation of the seismic demand of Korean earthquake datasets, which have distinct seismic characteristics from those of the US at a high-frequency range, a broadband frequency range optimization is suggested. The proposed data construction and seismic demand optimization method for seismic capacity re-evaluation are demonstrated and tested on a 480 V motor control center of a South Korea NPP.

• 한국융합학회논문지
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• 제10권11호
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• pp.85-93
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• 2019

한국은 반도체 산업에서의 독보적 우위에도 불구하고, 반도체 장비 분야에서는 두각을 나타내지 못하고 있다. 세정장비는 반도체 장비 중 한 분야로, 반도체 기술의 고도화에 따라 향후 중요성이 더욱 강조되는 분야이다. 본 연구는 특허 정보를 분석하여 한국을 포함한 주요 국가별 세정장비 분야 기술경쟁력을 파악하고 국가별 중점 기술분야를 살펴보고자 하였다. 이를 위해 최근 10년 간 미국 특허청에 등록된 세정장비 특허를 검색하여, 정량적 특허분석 및 특허 동시분류 네트워크 분석을 실시하였다. 연구 결과, 미국과 일본이 이 분야 기술을 선도하고 있는 것으로 나타났으며, 한국은 이들 선도국에 비해 경쟁력이 크게 뒤쳐짐은 물론, 경쟁국인 대만이나 후발국인 중국에 비해서도 우위에 있다고 보기 어려운 상황이다. 또한 국가별 전문화가 진행되어 있어, 국가 간 협력체제가 원활치 못할 경우 기술장벽으로 작용할 가능성도 없지 않다. 따라서 국내 세정장비 산업의 발전을 위한 적극적인 연구개발과 기술역량 확충이 요구된다.

• 대한인간공학회지
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• 제34권5호
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• pp.501-517
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• 2015

Objective: The aim of this study was to investigate the technology trend on developing helmets based on the analysis of Korean, US, European and PCT patents. Background: The usage of the personal protective equipment such as the safety helmet would be essential for preventing injuries and reducing the severity of injuries depending on the type of activity and the exposed environment. Method: Database of WIPSON was used for searching the patents. The objects were the Korean, US, European and PCT patents registered or opened from January 2011 to December 2014. The keyword to investigate was helmet, and International Patent Classification (IPC) was used for investigating the technology trend of the patents. Results: The cases of US patents annually increased, but the cases of European patents decreased. US patents belonged to all sections but Korean and European patents and PCT patents did not. The largest number of IPC, to which four areas' patents belonged, was 'Headwear' and the second largest one was 'Hygiene'. In the subgroup level, the most common largest subgroups were 'Parts, details or accessories of helmets' and 'Masks, shields, or hoods for welders'. Korean patents had the lowest ratio of single_IPC at 11%, but the ratios of single_IPC for US and European patents were 52%, respectively. 'Human necessities', 'Mechanical engineering', 'Physics', and 'Electricity' were used as a single_IPC, but lower levels of 'Performing operations', 'Chemistry', 'Textiles' and 'Fixed constructions' were used as multi_IPC. Most main applicants had patents which belonged to 'Human necessities'. Conclusion: The cases of US patents annually increased unlike others. The common technologies for creating the helmet were Parts of helmets under Headwear and Shields for welders under Hygiene. Many Korean patents tended to be categorized as multi_IPC, different from others. Application: To know the technological characteristic of patents would be helpful to initial stage developers.

• 무역학회지
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• 제45권4호
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• pp.171-194
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• 2020

Although there is a lot of literature on the effectiveness of regional trade agreements(RTAs), it is usually analyzed only using trade-related theories and data. However, this paper has a differentiation in that we examine the linkage between international trade and financial markets through the stock markets reactions when the trade agreements related news arrived. Specifically, using an event study, we look into the Korea-US free trade agreement(KORUS FTA) which is the most commercially significant FTA in almost two decades for both the countries. Korean stock market generally responded more sensitively to FTA news than the US stock market, especially in 'Auto & Parts', 'Electrical Equipment' and 'Chemicals' industries. And the investors' perception toward the effect of KORUS FTA on Korean industries changed from negative to positive as negotiations proceed. Korea has a comparative advantage in the production of labor-intensive goods relative to US, but the economies of scale hypothesis does not hold.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2005년도 추계학술대회 및 정기총회
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• pp.113-121
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• 2005

Virtual Manufacturing is a powerful methodology for developing a new product, new equipment and new production system. It enables us to check the errors in design before production. This paper deals with a case study of virtual manufacturing in an excavator factory. Boom and rotating table of upper body are selected for application. 3D models of parts and fixtures are developed with CATIA and 3D simulation models are developed with IGRIP. These models are used for the design of fixture to verify the motion of the equipment. As a result, the manual welding systems are replaced by automatic systems and many design errors are corrected in the design phase, which enables us to reduce the developing cost and time.

• 산업경영시스템학회지
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• 제17권32호
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• pp.209-220
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• 1994

In this paper, we study the timing and equipment of replacement. Those affect both available possibility and technological levels of new equipments in the future. These problems are classified according to technological levels and in consequence generated four circumstance. Models are formulated in this research. These are able to make us decision which we replace equipment at the first time. A method is suggested to find the optimal age for replacement at given each circumstance. A solution procedure and numerical example are given.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.455-456
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• 2007

Nowaday it is main issues for us to protect from the polluted water which is flowing in streams and rivers simultaneously. This paper proposed a water maintenance control system using pH sensor. Also the work enables water analysis downloading VHDL coding to FPGA through Max+plus II simulation tool for display realization.