• 한국산학기술학회논문지
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• 제18권10호
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• pp.125-130
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• 2017

자동차용 금속재료와 플랜트 모듈을 구성하는 소재가 동유럽, 러시아 북부, 캐나다 등과 같은 극한 지역(겨울 평균 기온 $-20^{\circ}C$ 이하)에서 운용되는 장비에서는 관련 부품의 결빙 등에 대한 대비가 필요하다. 또한 극한지 자원 에너지 개발, 각종 파이프라인 지하시공 증가 등으로 고온 및 저온의 내환경성이 우수한 기계 재료의 사용이 요구되고 있다. 하지만, 현재까지 초저온용 재료에 대한 고속 인장 실험의 경우에는 상온에서의 영향에 대한 연구만 일부 수행 되었을 뿐, 저온에서의 영향은 고속 저속에서의 차이가 있다는 정도만 확인이 되고 있다. 본 논문에서는 보편적 재료인 TP304, TP316소재의 상온 및 저온에서의 기계적 특성에 대한 비교 시험을 실시하여 두 재료의 저온 특성에 대하여 알아보았다. 인장시편은 KS B 0801의 표준 시험편을 사용하였으며, 실험장치는 특수 제작된 저온 인장 시험기를 사용하였다. 그 결과 TP304는 저온 영역에서 2차 경화 현상이 발생하였다. TP316은 저온 영역에서 연신율이 감소하였으며, 최대인장강도가 상온보다 증가하는 것을 확인하였다. 온도 의존성은 최대인장강도와 연신율은 TP304가 높았고, 항복강도는 TP316재료가 높게 나타난 것을 확인 할 수 있었다.

• 산업경영시스템학회지
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• 제41권1호
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• pp.94-101
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• 2018

With the development of industrial technology and science, production and manufacturing facilities have been enhanced and improved, and the importance of the safety of workers has also been regulated and limited by various safety management methods. As a way to secure the safety of the workers from the production facility, the fail-safe and fool-proof methods are now being applied. Any possible insecure behavior and unsafe conditions can be removed by adopting the standards and specifications that are now secure the safety of workers and equipment. This research analyzes EN ISO 13849-1 international and European standards during CE certification. In order to secure acceptable reduced risks, the risk assessment process of ISO 12100 and the processes for reducing its risk are applied. In the current ISO 13849-1 standard, the criteria for the required performance level PLr (Required Performance Level) for the applicable risk and safety functions through the risk assessment are subjective and not subdivided. Therefore, the evaluation criteria are likely to cause judge's judgement error due to qualitative judgement. This research focuses on evaluation and acceptable performance level setting for the safety circuit of the equipment. We propose an objective and specific evaluation criteria to secure safety, and the proposed evaluation criteria are applied to the case study of the safety circuit for the equipment. In order to secure the safety of the entire safety circuit, the improvement of the MTTFd and DC level related to the SRP/CS (Safety-Related Parts of Control Systems)' lifetime is required for the future research.

• 한국CDE학회논문집
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• 제20권1호
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• pp.65-74
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• 2015

Structure and/or fluid analysis is gradually increased by an essential design process in the small and medium-sized businesses (SMBs) because of the needs for a rapid design process and the certification about the supplement of the parts by the large business (LB). In this paper, we developed the web-based ezSIM platform installed in the resources integrated system server. The ezSIM platform is based on the heterogeneous linux and windows operating system for the user-friendly connection with the part of the analysis for the SMBs. The procedure of the structure/fluid analysis service module using the public software and the license-free open code in the ezSIM platform was explained. The convenience of the ezSIM platform service was presented by the reaction rate of the graphic motion compared with that of a local PC and the solving and pre-post processing interface compared with that of the KISTI supercomputer. The web-based ezSIM platform service was identified as a useful and essential platform to the SMBs for the usage of the structure and/or fluid analysis procedure.

• 한국인터넷방송통신학회논문지
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• 제20권4호
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• pp.165-170
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• 2020

빠르게 성장하는 신재생 ESS 부품 소재 시장 선점과 급변하는 세계 신재생 ESS 시장에서 국내 중소기업이 대응하기에는 한계가 있으며 이를 극복하기 위한 대·중소기업 협력 기반구축과 중·장기적으로 신재생에너지 산업육성을 촉진할 수 있는 신재생 ESS 융복합 사업화 지원센터를 구축할 필요성이 커지고 있다. 따라서 신재생 ESS 융복합 전문평가센터 기반구축을 통해 신재생 ESS 제품에 대한 성능평가 및 표준화를 통해 제품의 신뢰성을 높이고, 신재생 ESS의 신뢰성 확보를 통해 국내 보급사업 및 수출 활성화를 촉진할 수 있다. 또한, 국내 연구기관, 제조업체의 개발 역량 제고 및 경쟁력 강화를 지원하고 Total-test 시험평가 시스템에 따른 시험비용 및 시험 기간의 단축을 실현하여 국내 기업이 해외 시험기관을 이용할 때 발생할 수 있는 국내 기술의 유출방지 효과를 기대할 수 있다. 따라서 본 논문에서는 이러한 성능 평가 및 실증을 위해 표준화를 정립할 수 있는 선진국 수준 이상의 전문평가센터 구축을 연구하고자 한다.

• 에너지공학
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• 제23권2호
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• pp.183-190
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• 2014

국내 가동중원전은 2012년 이후 일반규격품 품질검증 이행 체계 구축을 위해 정책 수립 및 기술 개발, 일반규격품 품질검증 전문기관 양성, 국내 원전 공급사들의 일반규격품 품질검증프로그램 보유 추진 및 원자력 산업계의 전문인력 양성 등을 적극 추진 중에 있다. 아울러 미국 전력연구소(EPRI)의 관련 기술기준을 기반으로 일반규격품 품질검증프로그램 도입 초기에 개발된 안전성(Q) 등급 품목 품질검증 프로세스를 개선하였고, 국내 원전 고유의 원자력 품질등급 체계인 안전성영향(A) 등급 품목을 위해 안전성등급 품목과 차별화시킨 별도의 검증 프로세스를 개발하였다. 결과적으로, 위와 같은 노력을 통해 국내 가동중원전의 일반규격품 품질검증 이행 체계가 구축될 경우, 원전에서 사용하는 기자재의 신뢰성 및 안전성이 향상될 것으로 기대된다.

• 디지털산업정보학회논문지
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• 제13권4호
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• pp.57-69
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• 2017

The ability to use and utilize information technology devices in the knowledge-based society shows many differences in terms of quality of life. However, in the case of the elderly, the elderly suffer difficulties in acquiring information technology due to their aging characteristics, so they can not easily adapt to rapidly changing societies. Therefore, it is becoming more and more important to educate the elderly who are trying to adapt to the new environment of knowledge-based society. Therefore, in this study, we analyzed the previous researches of the researchers related to the elderly informatization education and the report of the actual situation of the digital divide of the government, and identified the problems and suggested ways to activate the effective education for the aged. The following suggestions are made to activate information education. First, there is a need for systematic promotion and professional counseling on the need for information education for the elderly learners. Second, the development of various curriculum that can be used in real life. Third, development of customized learning materials. etc. Fourth, Obtain a professional lecturer for the elderly. It is limited to lecturers who have completed teaching and learning methods that reflect the characteristics of the elderly. Fifth, the introduction of qualification certification system that can measure the level of informatization of the elderly learners. Sixth, building e-learning system for elderly people. Seventh, to establish a new organization dedicated solely to information education for the elderly. When these parts are realized, it will help elderly people to improve their quality of life through alleviation of solitude and alienation.

• 대한산업공학회지
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• 제39권3호
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• pp.172-182
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• 2013

In this study we consider a flow line CONWIP system in which two types of product are produced. The processing times of each product type at each station follow an independent exponential distribution and the demands for the finished products of each type arrive according to a Poisson process. The demands that are not satisfied instantaneously are either backordered or lost according to the number of unsatisfied demands that exist at their arrival instants. For this system we develop an approximation method to obtain the performance measures such as steady state probabilities of the number of parts of each product type at each station, mean waiting times of backordered demands and the proportion of backordered demands. For the analysis of the proposed CONWIP system, we model the CONWIP system as a two class closed queueing network with a synchronization station and analyze the closed queueing network using a product-form approximation method for multiple classes developed by Baynat and Dallery. In the approximation method, each subsystem is analyzed using a matrix geometric method. Comparisons with simulation show that the approximation method provides fairly good results for all performance measures.

• 한국안전학회지
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• 제34권6호
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• pp.88-95
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• 2019

It has been only a few years since drones have been introduced to Korea, and as the use of drones has increased in industrial sites as well as in hobby activities, accidents such as workers' body parts coming into contact with rotating propellers have been occurring since 2016. Industrial accident cases are being filed. In the case of a remote control vehicle, if you release the remote controller in the event of an abnormal situation, it stops in place and no further danger occurs but in case of drones flying over the sky is different. Sudden motor stops during flight, uncontrolled changes in flight posture, loss of radio waves, loose propeller, etc, numerous factors can lead to accidents due to unintentional movements. Therefore, drone operators need safety knowledge as well as high knowledge about drones. However, drones with a weight of less than 12 kg can fly without a pilot's certification, and therefore, a minimum accident prevention measure is required. 10 accidents approved as industrial accidents since 2016, 23 accidents surveyed by general drone operator, 40 accidents surveyed by the Korean Consumer Resources Unfortunately for the purpose of writing this paper, drones are a new species and do not have many parameters for analysis but my experience has shown that the type of disaster does not deviate significantly. In addition, there is no paper that analyzes drone related industrial accidents not only in Korea but also in other countries. However, even if you watch an overseas drone accident video through YouTube, it is not much different from the case that occurs in Korea. I hope that this study will be of little help to all the drone pilots as well as the work safety of industrial drones used in industrial sites.

• 한국기후변화학회지
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• 제9권2호
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• pp.197-207
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• 2018

The Korean government views coal-fired power plants as the key cause of the fine dust generation, and is developing an energy policy to replace and demolish old coal-fired power plants. According to the Eighth Power Supply Base Plan (2017-2031), the maximum power capacity in 2030 is expected to be 100.5GW, which is 17.9% higher than the current level (85.2GW). The plan aims to reduce the facility size and power generation ratio from nuclear and coal resources to even lower levels than today, and to rapidly expand power generation from new and renewable energy. Despite that, the proportion of coal power generation is still much higher than other resources, and it is expected that the reliance on goal will maintain for next several decades. Under such circumstances, the development, supply, and expansion of clean coal technology (CCT) that is eco-friendly and highly efficient, is crucial to minimize the emission of pollutants such as carbon dioxide and fine dust, as well as maximize the energy efficiency. The Korean government designated the Yong-Dong Thermoelectric Power Plant in Gangneung to develop clean coal power generation, and executed related projects for three years. The current study aims to suggest a plan to develop parts, technologies, testing, evaluation, certification, and commercialization efforts for coal-fired power generation, In addition, the study proposes a strategy to vitalize local economy and connect the development with creation of more jobs.

• Biomedical Engineering Letters
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• 제8권4호
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• pp.337-344
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• 2018

Additive manufacturing (AM) is an alternative metal fabrication technology. The outstanding advantage of AM (3D-printing, direct manufacturing), is the ability to form shapes that cannot be formed with any other traditional technology. 3D-printing began as a new method of prototyping in plastics. Nowadays, AM in metals allows to realize not only net-shape geometry, but also high fatigue strength and corrosion resistant parts. This success of AM in metals enables new applications of the technology in important fields, such as production of medical implants. The 3D-printing of medical implants is an extremely rapidly developing application. The success of this development lies in the fact that patient-specific implants can promote patient recovery, as often it is the only alternative to amputation. The production of AM implants provides a relatively fast and effective solution for complex surgical cases. However, there are still numerous challenging open issues in medical 3D-printing. The goal of the current research review is to explain the whole technological and design chain of bio-medical bone implant production from the computed tomography that is performed by the surgeon, to conversion to a computer aided drawing file, to production of implants, including the necessary post-processing procedures and certification. The current work presents examples that were produced by joint work of Polygon Medical Engineering, Russia and by TechMed, the AM Center of Israel Institute of Metals. Polygon provided 3D-planning and 3D-modelling specifically for the implants production. TechMed were in charge of the optimization of models and they manufactured the implants by Electron-Beam Melting ($EBM^{(R)}$), using an Arcam $EBM^{(R)}$ A2X machine.