• 한국정밀공학회지
• /
• 제18권4호
• /
• pp.85-96
• /
• 2001

In this paper, part features are classified and then its coding system is constructed by the considered characteristics of features in assemble process. Analyzing the characteristics of features, code values about part features are determined. Assembly process is divided into five functions such as transporting, handing, approaching, alignment and joining, and then the detail parameters of each functions such as determined. Code values about assembly process are determined according to detail parameters. The detail parameters are kinds of available working method and assembly tools when each assembly function is going on. By the coding system, available assembly process can be grasped and perceived for the part that it is difficult to assemble.

• 한국경영과학회:학술대회논문집
• /
• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
• /
• pp.28-31
• /
• 2000

In this paper, part features are classified and then coding system is constructed by the considering characteristics of features in assembly process. Analyzing the characteristics of features, code values about part features are determined. Assembly process is divided into five functions such as transporting, handling, approaching, alignment, joining and then the detail parameters of each function are determined. Code values about assembly process are determined according to detail parameters. The detail parameters are the kinds of available working method and assembly tools, when each assembly function is going on. By the coding system, available assembly process can be grasped and perceived the part that Is difficult to assemble.

• 한국정밀공학회지
• /
• 제16권5호통권98호
• /
• pp.29-39
• /
• 1999

Many industrial products can be assembled in various sequences of assembly operations. To save time and cost in assembly process and to increase the quality of products, it is very important to choose an optimal assembly sequence. In this paper, we propose a methodology that generates an optimal assembly sequence by using the knowledge of experts. First, a product is divided into several sub-assemblies. Next, the disassembly sequences of sub-assembly are generated using disassembly rules and special information can be extracted through the disassembly process. By combining every assembly sequence of sub-assemblies, we can generate all the possible assembly sequences of a product. Finally, the expert system evaluates all the possible assembly sequences and finds an optimal assembly sequence. It can be achieved under consideration of the parameters such as assembly operation, tool change, safety of part. basepart location, setup change, distance, and orientation. The developed system is applied to UBR(Unit Bath Room) example.

• 대한토목학회논문집
• /
• 제33권1호
• /
• pp.35-46
• /
• 2013

본 연구에서는 모듈러 강교량 상부모듈 구성파트의 효율적인 3차원 조립설계를 위하여 BIM(Building Information Modeling)의 핵심기술 요소인 파라메트릭 모델링 방법을 연구하였다. 모듈러 강교량 상부모듈 구성파트의 3차원 조립설계를 위하여 모듈의 조립체계를 상세수준(LoD: Level of Details) 3단계로 정의하였다. 모듈을 구성하는 각 파트들의 3차원 형상구성을 위한 요소들을 추출하여 매개변수, 매개변수에 따라 변하는 종속변수, 매개변수에 따라 변하지 않는 고정 값으로 구분하여 정의하였으며, 조립체계 단계에 따라 파트간의 공간적 조립규칙을 정의하였다. 공간적 위치를 구속하기 위하여 3차원 형상구성 요소간의 위치관계를 정의하였으며, X, Y, Z 축에 대한 자유도를 구속하기 위하여 기하학적 관계를 정의하였다. 또한, 정의한 조립규칙을 적용하여 모듈러 강교량 상부모듈의 3차원 조립설계를 위한 표준템플릿을 구축하였으며, 정의한 매개변수의 변화에 따른 강교량 상부모듈의 형상변화 검토를 통하여 파라메트릭 모델링 방법의 적용성을 검증하였다.

• 한국산학기술학회:학술대회논문집
• /
• 한국산학기술학회 2009년도 추계학술발표논문집
• /
• pp.715-718
• /
• 2009

The assembly line is one of the typical process hard to analyze with mathematical methods including even stochastic approaches, because it includes many manual operations varying drastically depending on operators' skills. In this paper, we suggest the simulation optimization method to design the optimal assembly line of a gas oven. To achieve the optimal design, firstly, we modeled the real gas oven assembly line with actual data, such as assembly procedures, operation rules, and other input parameters and so on. Secondly, we build some alternatives to enhance the line performance based on business rules and other parameters. The DOE(Design Of Experiment) techniques were used for testing alternatives under various situations. Each alternatives performed optimization process with evolution strategy; one of the GA(Genetic Algorithm) techniques. As a result, we can make about 7% of throughputs up with the same time and cost. By this process, we expect the assembly line can obtain the solution compatible with their own problems.

• 오토저널
• /
• 제6권1호
• /
• pp.36-45
• /
• 1984

The conventional heat transfer analysis methods based on the one-dimensional theory are not adequate to be applied for the purpose of finned surface design because the two-dimensional effects in fact are induced within the supporting wall by the presence of the finnes. In this study, the two-dimensional heat transfer of a straight fin assembly is analyzed by using the integral method. It is shown that all the effects of the system parameters i.e., the heat transfer parameters and geometrical parameters, on both the total heat transfer rate and the surface temperature effectiveness can be seen from the present analysis. The optimum combinations of these parameters for the design of finned surfaces may be estimated.

• 방사성폐기물학회지
• /
• 제21권3호
• /
• pp.359-370
• /
• 2023

The thermal integrity of spent nuclear fuels has to be maintained during their long-term dry storage. The detailed temperature distributions of spent fuel assemblies are essential for evaluating the integrity of their dry storage systems. In this study, a subchannel analysis model was developed for a canister of a single fuel assembly using the COBRA-SFS code. The thermal parameters affecting the peak cladding temperature (PCT) of the spent fuel assembly were identified, and sensitivity analyses were performed based on these parameters. The subchannel analysis results indicated the presence of a recirculation flow, based on natural convection, between the fuel assembly and downcomer region. The sensitivity analysis of the thermal parameters indicated that the PCT was affected by the emissivity of the fuel cladding and basket, convective heat transfer coefficient, and thermal conductivity of the fluid. However, the effects of the wall friction factor of the canister, form loss coefficient of the grid spacers, and thermal conductivities of the solid materials, on the PCT were predominantly ignored.

• 한국정밀공학회지
• /
• 제15권5호
• /
• pp.72-84
• /
• 1998

This paper studies the relationship between assemblability and assembly time. After analyzing characteristic factors of bolts and parts, seven different kinds of assemblability parameters were determined according to assembly process, and assemblability was also evaluated. MTM (Method-Time Measurement) and Work factor methods were used for an estimation of assembly time. It shows the relationship can be found on the basis of characteristic factors of parts and bolts by relational graphs and numerical formulas.

• International Journal of Precision Engineering and Manufacturing
• /
• 제1권2호
• /
• pp.35-42
• /
• 2000

To save time and cost in assembly process and to improve th quality of products, it is very important to choose and optimal assembly sequence. In this paper, we propose a methodology that generates an optimal assembly sequence by using various methods and the knowledge of experts. To illustrate the effectiveness of the proposed methodology, a knowledge-based system is developed, The built system is applied to the case of UBR(Unit Bath Room). The applying result showed the applicability of the developed system.

• Nuclear Engineering and Technology
• /
• 제39권1호
• /
• pp.43-50
• /
• 2007

A partial flow blockage in an assembly of a liquid metal reactor could result in a cooling deficiency of the core. To develop a partial blockage detection system, we have studied the changes of the temperature fluctuation characteristics in the upper plenum according to changes of the t10w blockage conditions in an assembly. We analyzed the temperature fluctuation in the upper plenum with the Large Eddy Simulation (LES) turbulence model in the CFX code and evaluated its statistical parameters. Based on the results of the statistical analyses, we developed a neural network model for detecting a partial flow blockage in an assembly. The neural network model can retrieve the size and the location of a flow blockage in an assembly from a change of the root mean square, the standard deviation, and the skewness in the temperature fluctuation data. The neural network model was found to be a possible alternative by which to identify a flow blockage in an assembly of a liquid metal reactor through learning and validating various flow blockage conditions.