• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.907-910
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• 2012

Since the inner barrel assembly of the Advanced Power Reactor 1400 reactor vessel is a new design feature introduced instead of CEA(control element assembly) shroud assembly, the inner barrel assembly can be a significant object of structural integrity assessment. This paper covers the structural responses of top plate, which is a component of the inner barrel assembly, against the deterministic hydraulic load induced by pump pulsation and the random hydraulic load induced by turbulence of coolant. The top plate responds to the deterministic hydraulic load more than to the random hydraulic load and shows enough structural integrity. The results of this paper will be important basis for the selection of instruments and measurement location.

• Smart Structures and Systems
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• 제32권2호
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• pp.111-121
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• 2023

This study proposes an automated assembly performance evaluation method for prefabricated steel structures (PSSs) using machine learning methods. Assembly component images were segmented using a modified version of the receptive field pyramid. By factorizing channel modulation and the receptive field exploration layers of the convolution pyramid, highly accurate segmentation results were obtained. After completing segmentation, the positions of the bolt holes were calculated using various image processing techniques, such as fuzzy-based edge detection, Hough's line detection, and image perspective transformation. By calculating the distance ratio between bolt holes, the assembly performance of the PSS was estimated using the k-nearest neighbors (kNN) algorithm. The effectiveness of the proposed framework was validated using a 3D PSS printing model and a field test. The results indicated that this approach could recognize assembly components with an intersection over union (IoU) of 95% and evaluate assembly performance with an error of less than 5%.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.400-404
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• 1997

This paper presents spatial relationshaps and engineering features for the feature based modeling of Sheet Metal Weld Assemblies (SMWA) that are made of sheet metal components through are welding processes. Spatial relationships in ProMod-S, a sheet metal product modeler,are further extended for the SMWA modeling. Some spatial relationships for special weld joint types are newly introduced. The geometrical and topological relations between spatial reationship, mating features, and assembly features are defined. Finally, assembly data stucturess for the product modeling of SMWA are proposed. They are an engineering relation to represent the constraints between component features, and a mating bond to integrate component design information.

• 대한기계학회논문집
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• 제13권1호
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• pp.48-58
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• 1989

이 논문의 목적은 사용자가 부품간의 연결정보로는 단지 만남조건 (mating condition)만을 입력함으로써 조립체가 생성이 되고 또 그로부터 동역학 또는 기구학적 해석 프그램과의 연결을 위한 정보가 유도되는 조립체 모델링 시스템(assembly modeling system)을 개발하는 것이다. 만남조건을 통해 조립체를 생성하는 방법은 이미 Rocheleau와 Lee에 의해 개발되었으나 그들은 주로 각 부품의 위치를 찾아내는 데에만 관심을 두었고 본 논문에서는 그것의 확장으로 해석 프로그램과 연결시키는데 필요한 정보의 유도를 추가로 고려하였다.

• 전기화학회지
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• 제17권3호
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• pp.139-148
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• 2014

Electrochemical energy-storage devices such as batteries and supercapacitors are important components in emerging portable electronic device, electric vehicle, and clean energy storage and supply technologies. This review describes recent progress in the development of nanostructured electrodes, the main component of the electrochemical energy-storage device, prepared by layer-by-layer (LbL) electrostatic assembly. Major advantages associated with, and challenges to, the fabrication of LbL electrodes, as well as the future outlook for expanding the application of LbL techniques, are discussed.

• 한국CDE학회지
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• 제8권3호
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• pp.40-51
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• 2002

Design and manufacturing (or production) must be closely interrelated. They should never be viewed as separate disciplines or activities. Each part or component of a product must be designed so that it not only meets design requirements and specifications, but also can be manufactured and assembled economically, ecologically and with relative ease. This approach improves productivity and allows a manufacturer to remain competitive. This broad view has become recognized as the area of design for manufacture and assembly(DFMA). Here the principles of the DFMA and their some examples are reviewed.

• 품질경영학회지
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• 제10권2호
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• pp.10-17
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• 1982

Three different manual assembly techniques are evaluated by relating the effects of component quality to the total cost of the product. The results show that the choice of the scrapping or repairing the defective products or alternatively, salvaging the acceptable parts, may effect the total product cost by as much as 400 per cent. This paper emphasizes the need for accurate control quality of parts in assembly if low-cost manufacture is to be achieved.

• 대한산업공학회지
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• 제20권4호
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• pp.23-35
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• 1994

Efficient operation of a component placement machine with a multi-head in a PCB assembly process is considered. The problem consists of two subproblems, which are the optimal allocation of the component tape reels in the rack and the optimal mounting sequence of the components on a printed circuit board. We analyze the problem and propose a heuristic algorithm to solve it. The heuristic can be used for the one head case too. Computational experiences on some real world problems show the effectiveness of the heuristic in terms of speed and solution quality.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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• pp.632-635
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• 2004

PCB assembly is a complicated and difficult process to optimize due to the necessity of simultaneous consideration of rack assignment and board mounting sequencing. An efficient component mounting method is developed using component gathering phenomenon. It is found that same components are located closely each other by checking PCBs in field and interviewing PCB designers. A new method counting this phenomenon is developed and it is performed better with more number of total components and more number of gathered components cases. Simulation models are developed using Visual C++ for performance evaluation of the heuristic.

• 한국CDE학회논문집
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• 제17권1호
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• pp.1-6
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• 2012

The End Coupling is main component of the aluminum hot roll process. The End Coupling is used for transmission of rotational power with heavy-duty load. Fracture of the End Coupling cause serious economic losses because an End Coupling is a very expensive component and it takes a long time to repair it. Therefore, preventing the destruction of the End Coupling is essential for ensuring a long mechanical life cycle. In this paper, the parametric study on the End Coupling was performed in order to minimize maximum stress under operation loads. To verify the interference of spindle assembly with modified End Coupling, kinematics simulation was performed by applying the various combination type and dynamic boundary condition of the spindle assembly. The interference of optimized model was not occurred during combination process and driving process. As a result of an optimum design for life extension on End Coupling, the maximum stress of modified End Coupling was lower than that of the initial model by 26%.