• 산업경영시스템학회지
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• 제17권32호
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• pp.105-112
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• 1994

The purpose of this paper is to develope a heuristic algorithm to maximize reduction rate of the processing time by the connection of neighbored machines. A method to calculate the start-lag and stop-lag for the overlapping production is proposed and applied. The heuristic procedure of this paper has 3 steps. In the first and second step, the job oriented procedure is applied. In the final step, the operation oriented procedure is applied. In order to evaluate the performance of this algorithm, three kinds of performance measures are selected and randomly generated problems are tested.

• Coupled systems mechanics
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• 제5권4호
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• pp.329-340
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• 2016

The trigonal shape memory alloys (SMAs) have a great potential to be utilized as the applications with special purposes, such as actuators with high operation frequency. Most studies on the trigonal microstructures typically focus on the well-known classic herringbone pattern, but many other patterns are also possible, such as non-classic herringbone, toothbrush and checkerboard patterns. In the current work, a systematic procedure is developed to find all possible laminate twin microstructures by using geometrically linear compatibility theory. The procedure is verified by SEM images with the information of crystallographic axes of unitcells obtained by EBSD, showing good agreement. Many interesting trigonal R-phase patterns are found in the specimen. Then, their incompatibility are analyzed with nonlinear compatibility theory. The relationship between such incompatibility and the likelihood of occurrence of the microstructures is revealed. The current procedure is rapid, computationally efficient and sufficiently general to allow further extension to other crystal systems and materials.

• Journal of applied mathematics & informatics
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• 제7권1호
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• pp.237-245
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• 2000

In this paper, we consider to the adjustment weighting procedure in the two phase sampling scheme. In general, the unit nonresponses may be occured in the final survey operation. When the unit nonresponse be generated in survey, it is able to use the auxiliary variable for estimating of interest variable. In this viewpoint, we use the two kinds level of auxiliary variable, $X_{1k}$ and $X_{2k}$ for the calibration procedure. We proprose the two-step Newton's method in the calibration estimation procedure for the two phase sampling.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.643-652
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• 2009

This paper presents brief history and a state-of-the-art survey of Life Cycle Cost (LCC) analysis, in particular LCC analysis in the Urban Transit Vehicle, based on a internationl codes and standards related to LCC analysis. A main objective of the LCC analysis is to quantify the total cost of ownership of a product throughout its full life cycle, which includes research and development, construction, operation and maintenance, and disposal. The predicted LCC is useful information for decision making in purchasing a product, in optimizing design, in scheduling maintenance, or in planning overhaul. This paper presents a LCC procedure consisting of seven steps, which are "Problems definition", "Cost elements definition", "System modeling", "Data collection", "Cost profile development", "Evaluation", and "Verification". Sub-activities to be encompassed in the seven steps procedure are described.

• 전자공학회논문지A
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• 제31A권6호
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• pp.199-208
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• 1994

This paper proposes a delay fault test technique for ICs and PCBs with the boundary-scan architectures supporting ANSI/IEEE Std 1149.1-1990. The hybrid delay fault model, which comprises both of gate delay faults and path delay faults, is selected. We developed a procedure for testing delay faults in the circuits with typical boundary scan cells supporting the standard. Analyzing it,we concluded that it is impractical because the test clock must be 2.5 times faster than the system clock with the cell architect-ures following up the state transition of the TAP controller and test instruction set. We modified the boundary-scan cell and developed test instructions and the test procedure. The modified cell and the procedure need test clock two times slower than the system clock and support the ANSI/IEEE standard perfectly. A 4-bit ALU is selected for the circuits under test. and delay tests are simulated by the SILOS simulator. The simulation results ascertain the accurate operation and effectiveeness of the modified mechanism.

• 산업공학
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• 제12권1호
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• pp.26-31
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• 1999

Evolutionary Operation(EVOP) is a method for continuously monitoring and improving a full-scale process to get an optimal operating condition while production is under way. To avoid appreciable changes in the product quality characteristics only small changes are made in the levels of the process variables. One of the reasons why EVOP is not so popular is that people in charge of the EVOP is blamed when the EVOP does not produce good results. We present an EVOP procedure when prior information of the relationship between defect types and process variables is known. The procedure is illustrated with an injection molding case study.

• 대한산업공학회지
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• 제18권1호
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• pp.63-80
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• 1992

The concept of rapid prototyping intended for a significant reduction in cost and lead time becomes even more practical with the recent development of various equipments to make the concept concrete. For the purpose of real application of commercially available SLA(stereolithography apparatus), this paper is intended to develop the standard conversion procedure from CAD data to the input data for SLA. While the procedure presented in this paper is based on CAD system "CATIA" and SLA of 3D systems, Inc., which are being used in authors' company DAEWOO Motor Co., Ltd., the basic concept of this paper can be applied to any other CAD systems and machines of using stereolithography process. The algorithm presented in this paper is classified into two stages-node sampling and triangulation. First of all, point data are sampled through the node sampling procedure, and then these are triangulated so that the input data for SLA operation is finally generated. The suggested method is devised in a way to meet the input requirements of SLA and more importantly consume less computation time and generate less number of input data for SLA.

• 한국신뢰성학회지:신뢰성응용연구
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• 제17권4호
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• pp.305-315
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• 2017

Purpose: The purpose of this research is to propose procedure and methodology for developing failure rate databook which is suitable for Korean operation environment. Methods: To this end, we investigate failure databooks used in foreign countries and study the procedure and methodology for collecting failure data, organizing the data, estimating failure rate and summarizing results. Results: We develop the procedure of development of failure databook, the items for data collection, database schema of part details and part summary and contents of failure databook by considering the application environment in Korea. Conclusion: The results of our research could be utilized for the development of Korean failure rate databook and research of reliability prediction model and could ultimately contribute to improve the accuracy of reliability prediction.

• 대한두개안면성형외과학회지
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• 제23권3호
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• pp.134-138
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• 2022

The scalp is the thickest skin in the body and protects the intracranial structures. The coverage of a large scalp defect is a difficult surgical procedure, the full details of which must be considered prior to the procedure, such as defect size and depth, and various factors related to the patient's general condition. Although a free flap is the recommended surgical procedure to cover large scalp defects, it is a high-risk operation that is not appropriate for all patients. As such, other surgical options must be explored. We present the case of a patient with an ulcer on the scalp after wide excision and split-thickness skin graft for squamous cell cancer. We successfully performed a reverse temporalis muscle flap for this patient.

• 대한교통학회지
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• 제20권1호
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• pp.19-38
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• 2002

일반적으로 교통운영 시스템에 대한 효과를 평가하기 위해서 구간통행 시간, 통행속도, 지정체율 등과 같은 효과척도(MOE: measure of effectiveness)가 사용된다. 그러나, 에너지에 대한 관심이 극히 높은 상황에서는 기존의 교통측면의 효과척도 이외에 에너지소모라는 효과척도가 교통운영시스템의 MOE로서 대안평가에서 점차로 중요한 영향을 발휘할 수 있다. 본 연구는 교통운영방식별 에너지효율성에 대한 평가를 위해 (기존에 주로 사용되던 효과척도로서의 구간평균속도, 구간평균통행시간, 지정체 뿐 아니라), 에너지 소모 또한 대안평가에 사용할 수 있을 것으로 판단하여, 각 대안별 에너지 소모를 상대적으로 측정하여 볼 수 이는 절차를 개발하고 상호 그 결과를 비교하고자 하였다. 이를 위해 메조모형 시뮬레이터인 Integration이 사용되었으며, HOV 차로 운영, 신호 최적화, 차로 확장, ITS 적용에 대한 대안의 평가를 수행하였다. 이중ITS의 적용이 에너지 절감에 가장 큰 효과가 있는 것으로 나타났으며, 차로확장, 신호최적화, HOV 차로 운영 순으로 에너지 절감 효과가 나타났다. 본 연구는 차종에 대한 특성의 고려, 잠재수요에 대한 고려를 하지 않았으며, 분석 기간이 단지 첨두 1시간에 그쳤기 때문에 향후 이러한 현실적 요소에 대한 고려 및 시스템의 확대적용에 있어 보다 정확한 경제성 분석절차 및 방법론적 개선이 요구된다고 하겠다.