The RPV internal structure is a high radio activated part and has very complex geometry. Therefore, it needs to be cut remotely with an automated cutting system to minimize the worker exposures. To do so, we made up the remote laser cutting system with a laser cutter, robot manipulator and control software system and the laser cutter is moved by the robot manipulator based on the command from the control software system. A laser cutter is required to keep the desired standoff position between the nozzle of the laser cutter and surface of the cut target model to cut properly. Moreover, in the remote cutting process, an exact time and sequence control of the air supply and the laser emission is required for the cutting quality and the process safety. In this study, we proposed the PERT chart-based process execution and control methodology. The PERT chart is a graph which is represented by nodes and edges. The node of the PERT chart has the information about the activity details such as activity type, execution time and related device. Using the edge we make the sequence of the desired activity execution. A PERT chart of the cutting scenario is compiled in the control software system to creates data and thread structure to operate the physical device. We built software architecture to interpret and execute the PERT chart efficiently in the digital simulation platform which enables us to use existing pre-built simulation scenario for the laser cutting process. In addition, we have tested various laser cutting test cases in our test bed to verify the performance of our system. The test bed environment has the shape of the RPV internal structure and is placed under water.

For highly contaminated elements such as reactor pressure vessels or reactor internals, it is a viable option to cool-down and dismantle these elements in submerged (e.g. underwater) state. Several tools and processes such as saw cutting, water jet cutting or plasma cutting are currently used for underwater cutting, with each of them having their own advantages and disadvantages. The main disadvantage of these existing methods, especially saw and water jet cutting, is the generation of secondary waste that then needs to be filtered out of the water. In addition, in the case of water jet cutting, a considerable amount of abrasive material is added, which must also be stored. To overcome this drawback, the feasibility of using laser cutting under water to minimize secondary waste production has been actively studied recently. One of the challenges with the underwater laser cutting is to visually monitor the cutting process. Flowing air bubbles generated by the cutting gas and the flashing light emitted from the laser and melting material prohibit visual monitoring of the cutting process. This study introduces a method to enhance the video from a monitoring camera. Air bubbles can be detected by computing optical flows and the video quality can be enhanced by selective removal of the detected bubbles. In addition, suppressing the frame image update from flashing light area can also effectively enhance the video quality. This paper describes the simple yet effective video quality enhancement method and reports preliminary results.

The decommissioning process of Kori Nuclear Power Plant No.1, which was permanently suspended in 2017, various studies and attention on the decommissioning of nuclear power plants and waste management are being focused. In particular, decommissioning of high-risk facilities should take into account both safety and economic aspects. Small defects in the decommissioning process may lead to major disasters, and the resulting economic losses will cause enormous damage at the national level. In order to prevent such damage, various decommissioning process simulations within a virtual environment should be performed, and process errors and results should be collected and analyzed through simulation to derive the optimal decommissioning scenario as possible. The platform introduced in this paper builds a virtual environment based on drawing and modeling data of Kori Nuclear Power Plant No.1 and automatically creates an optimized cutting path for dismantling the facility and internal structure, and simulates a cutting process similar to reality using Robot Arm. In addition, it is possible to derive and analyze a cutting process scenario by processing process results such as time required for work and cutting distance collected through simulation.

선박의 건조공정 중 강재의 절단과 곡 가공, 용접에 있어 화염의 사용은 필수적이다. 현재 조선소의 강재 절단과 가공 과정에서 는 아세틸렌이 화염 연료로 가장 많이 사용되고 있지만, 폭발 사고의 위험성과 상대적으로 적은 발열량의 한계로 최근에는 프로판 연료의 활용이 증가하고 있다. 하지만 프로판 연료는 상대적으로 가공 속도가 느리고, 가공 시 슬래그의 발생빈도가 높아 품질이 저하된다. 대체 연료로써 프로필렌이 주목받으며 가공 속도와 품질향상에 대한 기대가 증가하고 있다. 프로필렌은 발열량이 우수한 연료로 강재 가공 간 생산성과 가공 품질의 우수성을 갖추고 있다. 이에 본 논문에서는 프로판, 프로필렌 화염을 이용한 철판 가공 시 각 연료의 연소 특성을 분 석 및 비교하였다. 프로필렌 화염을 이용한 철판 가공 시 배출되는 온실가스와 유해가스를 프로판 연료의 배출량과 비교하여 저감효과를 실험적으로 확인하였다. 또한, 가공 연료에 따른 입열량이 선박용 강재의 기계적 강도 변화에 미치는 영향을 알아보기 위해 열 분포실험과 인장시험을 수행하였다. 실험 결과로, 대체 연료인 프로필렌을 사용할 때 프로판 연료에 비해 온도분포가 고르게 나타났다. 기계적 강도 실 험 결과로 인장강도의 저하는 관찰되지 않았으나, 변형률은 감소하는 경향을 보였다. 본 연구의 결과를 바탕으로 향후 실제 조선소의 강재 가공 및 절단과정에 적용하였을 때, 발생하는 문제점에 대한 분석 및 보완연구를 수행할 예정이다.

High luminance LED fluorescent light is replaced by halogen light in recent light parts. The housing cover of LED fluorescent light is used many several materials. Though deformity character has less value, polycarbonate cover has cheap, high strength and it is used general purpose. This study is several purposes. 1. No entering foreign matters during continuous extrusion manufacturing process in cutting process, 2. No deformity, exact cutting of pc length and finding method of cutting manufacturing process for polycarbonate cover

The package loading process of the lumbering industry is an operation that after a pair of workers bind three or six lumbers into one unit and cut both ends of the lumbers, transports the weight cargo of 30-50kg by one meter, pack and load at a height of 1.2 meters. This package loading process causes lots of noise and wood dust when workers carry out the heavy work as the above. Therefore we developed the monolithic both ends cutting package loading equipment in order to prevent from getting musculoskeletal disease. An loading bar working system of this equipment is improved from pneumatic pressure system to oil pressure system, furnished the newly designed flow dividers, and developed the new system that a both end array is loaded identically. Also we developed the safety equipment of loading bar in order to prevent workers mistake and overload from malfunction during the package loading process. The main cause of job evasion on working place could be solved by preventing the musculoskeletal disease and improving the working environments.

The package loading process of the lumbering industry is an operation that after a pair of workers bind three or six lumbers into one unit and cut both ends of the lumbers, transports the weight cargo of 30-50kg by one meter, pack and load at a height of 1.2 meters. This package loading process causes lots of noise and wood dust when workers carry out the heavy work as the above. Therefore we developed the monolithic both ends cutting package loading equipment in order to prevent from getting musculoskeletal disease. An loading bar working system of this equipment is improved from pneumatic pressure system to oil pressure system, furnished the newly designed flow dividers, and developed the new system that a both end array is loaded identically. Also we developed the safety equipment of loading bar in order to prevent workers mistake and overload from malfunction during the package loading process. The main cause of job evasion on working place could be solved by preventing the musculoskeletal disease and improving the working environments.

  The package loading process of the lumbering industry is an operation that after a pair of workers binds three or six lumber into a unit and cut the both ends of the lumber, carry and pack and load the weight cargo of 30-50㎏. The package loading process

신선편이용 절단배추의 선도유지 및 갈변 방지 목적으로 질소 치환 및 세라믹 칼날에 의한 절단 효과를 조사하였다. 저장 5일 이후부터 대조구에 비하여 NC 처리구의 중량변화 와 갈변도가 적게 나타났다. 질소 치환과 세라믹 칼날의 사용에 의한 절단 공정의 개선이 절단채소의 선도 유지와 갈변 방지에 효과가 있을 것으로 생각된다.

현재 각 관리 주체별로 절토사면에 대한 유지관리를 시행하고 있으나 평가항목 및 평가모형이 다양하고 접근방법이 상호보완적이지 못하므로 보편성 및 객관성이 부족한 실정이다. 따라서, 본 연구는 기존 절토사면 평가기법에 대한 분석을 통하여 합리적인 모형개발을 위한 접근을 시도하고 붕괴사례 분석을 통하여 붕괴 주요원인 및 인자를 발굴하고 이를 계층분석기법(AHP)을 이용하여 기존 절토사면의 조사․평가단계에서 조사우선순위를 결정하기 위한 평가표를 작성하였다.

작약(芍藥)의 화력건조시(火力乾燥時) 연탄건조(煉炭乾燥) 및 열풍건조(熱風乾燥)의 조건을 적절히 조절한 우수(優秀)건조방법과 절제품(切制品) 판매(販賣)를 목적으로 약재(藥材)를 절단시(切斷時)에 수침 및 밀봉시간을 구명코자 시험을 수행한 결과를 요약하면 다음과 같다. 1, 연탄화력(煉炭火力) 건조후 열풍건조할때는 건조시간이 60시간으로 길어 건조노력이 많이 소요되나 이렇게 건조시킨 작약(芍藥)은 아황산가스의 항산화작용(抗酸化作用)으로 백색(白色)을 나타내어 상품성이 높았고, 열풍건조방법은 건조시간이 단축되나 갈변으로 색택이 불량하여 상품성이 저하되었다. 2. 건조방법에 따른 작약(芍藥)의 주약용(主藥用) 성분(成分)인 Paeoniflorin 함량 변화는 2.48%~2.81%로 큰 차이는 없었으나 열풍건조에서 조금 낮은 경향이있다. 3. 양질의 작약(芍藥) 약재(藥材)를 생산하기 위한 화력건조방법은 연탄화력(煉炭火力)에 6시간이상 예건(豫乾) 후(後) 열풍건조를 추가하여 총 60시간 정도 건조하는 것이 약효성분함양(藥效成分含量)과 색택면에서 적절한 건조방법이었다. 4. 절제방법(切制方法)에 따른 Paeoniflorin 함량은 절단작업 이전(以前)의 수침시간(水浸時間)이 길어질수록 감소하였지만 밀봉시간(密封時間)이 경과함에 따라 다소 증가하는 경향이었다. 5. 건조고약(乾燥考藥) 절제품(切制品)의 상품성(商品性)에는 수침시간보다는 밀봉시간의 영향이 컸고 밀 봉시간이 경과할수록 부스러지지 않고 매끈하게 절단되어 우수하였는데 절단후 건조시간이 길어지는 단점은 있었다. 6. 건조작약(乾燥芍藥)을 30분 정도 수침 후 12시간 밀봉처리 한 후 절단하는것이 건조시간이 단축될 뿐만 아니라 Paeoniflorin 함량 및 상품성을 향상시킬수 있어 가장 효과적인 절단전(切斷前) 처리 방법이었다.