• The Korean Journal of Applied Statistics
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• v.24 no.5
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• pp.791-797
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• 2011

This paper considers the issue of seasonal cointegrating rank selection by information criteria as the extension of Cheng and Phillips (2009). The method does not require the specification of lag length in vector autoregression, is convenient in empirical work, and is in a semiparametric context because it allows for a general short memory error component in the model with only lags related to error correction terms. Some limit properties of usual information criteria are given for the rank selection and small Monte Carlo simulations are conducted to evaluate the performances of the criteria.

• Journal of information and communication convergence engineering
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• v.6 no.1
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• pp.59-63
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• 2008

The methods or algorithms which can accelerate simulation speed became of great importance, as the modeling and simulation methodology for discrete event systems is used in many areas such as model validation/verification and performance evaluation. This paper proposes a tool named, DEVSIF composer. The tool is made of an automated compiled simulation technology and it builds a new composed model which can be executed much fast by composing the component models together. Models are described by our new specification language DEVSIF, which is compatible with object-oriented language and supports representation of a hierarchical model structure. Experimental results demonstrates that DEVSIF composer enhances the simulation speed of a transformed DEVS model 5 times faster than that of the original ones in average.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.6
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• pp.915-922
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• 2008

The gas separation technology using membrane is widely used to refine various gases in many industry fields and recently is being applying in $CO_2$ recovery technology. In the gas and chemical tanker. nitrogen generators for inerting, purging and padding are on board and most of them have membrane modules of hollow fiber type with long life and vibration resisting properties. Because a membrane module is a key component accounting for 50% of total manufacturing cost of nitrogen generator, adequate selection for it is an important problem. In this paper, the flow performance coefficient based on dimension and specification data of membrane module was relatively selected to compare nitrogen generating capacity of module and various performance tests about the selected PARKER ST6010 membrane module were conducted. As a result, the useful coefficient and basic data in selecting a membrane module were achieved.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.540-545
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• 2008

The design on balance shaft module is performed based on the target specification of engine module as well as the its own dynamic nature under a high speed rotation. However, the specific information for engine module is not always available for non-motor companies even though a reliable analytical result should be attached in the conceptual design process or more detail works. In this paper, the analysis on balance shaft module, both each parts or module itself, is suggested to estimate the performance on the target component with respect to durability and NVH without any consideration of a engine module. This methodology could modify the nominal balance shaft model before the production of prototype such that cost reduction as well as time saving can be expected during design process of balance shaft module.

• Journal of Applied Reliability
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• v.17 no.1
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• pp.28-37
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• 2017

Purpose: This paper proposes a procedure that may infer and identify interaction failures in a module. Methods: In design FMEA, we defined an interaction model between components and proposed a method for selecting a single component by using the standard specification classification table and four methods for choosing the related components. We also introduced the function tree for function and requirement characteristic analysis and proposed utilization of standard stress lists and 1st and 2nd stress analysis tables to determine the effect the stress analysis has on interactions. Finally, the interaction mechanism diagram was proposed and used to infer the failure mechanism. Process FMEA also established procedures in a similar way. Results: We established a procedure for predicting the failure mode due to interaction between components based on Company A's multi-step FMEA procedure. Conclusion: By applying the proposed interaction FMEA procedure to the development model, we were able to confirm the effect of the new derivation on the failure mode of interaction, which was not predicted by the existing FMEA.

• Journal of the Korean Society for Railway
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• v.3 no.3
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• pp.170-176
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• 2000

Nowadays, the vehicle structure weight of urban transit system has been reduced in order to save energy and materials. However, this light weighted vehicle structure is very important to verify the fatigue strength at the development stage. Bogie system consists of bogie frame, suspensions, wheel-sets, braking system and transmission system. Among these components, the bogie frame is most significant component subjected to the whole vehicle and passenger loads. In this study, the bogie frame for the standard EMU power car is evaluated to the static and fatigue strength. And, the evaluation method is used the JIS E4207 specification throughout the FEM analysis and static load test. The static and fatigue test results for the standard EMU bogie frame of power car has been appeared very safety and stable for the design load conditions.

• Journal of the Korean Society of Safety
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• v.12 no.4
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• pp.21-26
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• 1997

Korea Atomic Energy Research Institute (KAERI) developed a risk monitor called Risk Monster which supports for plant operators and maintenance schedulers to monitor plant risk and to avoid high peak risk by rearranging maintenance work schedule. Risk Monster can update the plant risk continuously according to the change of system/component configuration since Risk Monster reevaluates the plant risk based on the Probabilistic Safety Assessment (PSA) results. A brief description of Risk Monster is provided. The PSA model of UCN 3, 4 nuclear power plant was converted by KAERI to Risk Monster model. Using this Risk Monster model, a feasibility study of the on-line maintenance of an Essential Service Water (ESW) pump was performed. On-line maintenance of one ESW pump has been shown to be acceptably safe, and has economic benefits. In addition, it is not a violation of technical specification to continue plant operation with an out-of-service ESW pump.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04b
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• pp.997-1000
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• 2001

컴퓨터와 인터넷 사용의 대중화 시대가 열리면서 소프트웨어의 구조도 점차 복잡해짐은 물론 크기도 방대해지고 있으나 S/W 개발 기술 발전 속도는 매우 더디어 소프트웨어 개발과 유지보수 비용의 증가로 인해 소프트웨어 위기 문제가 발생하게 되었다. 이에 대한 대안으로 소프트웨어 생산성, 품질, 효율성을 높이기 위해서 부품화와 조립의 특성을 지닌 컴포넌트 기반 개발 방법이 제시되었다. 컴포넌트 명세에 있어 기존에 이미 많은 명세 언어가 사용되고 있으며, 이들은 나름대로의 장점을 가지고 있으나, 이들은 대부분 구현에 있어 특정 언어에 의존성이 강하며, 표현 능력에 한계를 가지고 있다. 이러한 한계를 해결하기 위해 문제 요구사항에 대한 설명, 컴포넌트의 기능, 그리고 컴포넌트 구조에 대한 명확한 정의를 제공하는 정형화된 명세 언어에 대한 연구가 현재 이루어지고 있으나, 대부분이 컴포넌트 명세 기법에 대한 표준이 없고, 명세서에 대한 데이터 모델링 방법 및 표현언어에 대한 기준이 없이 컴포넌트의 구문적 측면만을 고려한 개발을 하고 있는 실정이다. 본 논문에서는 컴포넌트 명세서를 규격화하고 규격화된 명세서를 표준 메타 언어인 XML 기반으로 모델링 하고자 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04b
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• pp.1005-1008
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• 2001

이 연구에서는 웹 기반 시스템의 분산되어 있는 자료 활용이 미비하고 시스템을 개발 할 때 시스템 사용자(여기에서는 교수 - 학습자)들의 요구사항이 충분히 반영되지 못하는 점을 개선하기 위해 WBSE(Web Based Software Engineering)개념을 웹 기반 시스템에 도입하여 요구사항을 반영하고 기존에 개발되어 사용되고 있는 소프트웨어를 컴포넌트화 하는 작업을 시도하여 이를 재사용 통합함으로써 새로운 시스템을 개발하는데 재사용 하고자 한다. 특히 기존 웹 기반 시스템에서 재사용 할 수 있는 컴포넌트를 추출하여 특정 시스템(웹 기반 교육 시스템)에 재사용하는 일련의 과정에 대하여 연구 기술하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10a
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• pp.527-530
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• 2000

최근의 소프트웨어 위기를 해결할 수 있는 최적의 대안으로서 컴포넌트 기술을 개발, 산업계에 확산하기 위하여 다양한 영역의 비즈니스 컴포넌트를 개발 보급하여야 한다. 비즈니스 컴포넌트를 개발하기 위하여는 컴포넌트의 조립 모델을 정의한 개념적 아키텍쳐를 우선적으로 설정하여야하며 이 모델에 기반한 체계화된 명세 방법을 정의하여 각 컴포넌트가 일관적 체계에 따라 명세화되어 개발할 수 있는 체계를 구축하여야 한다. 본 연구에서는 정통부 사업의 일환으로 수행된 공용 컴포넌트 뱅크 구축을 위한 영역 아키텍쳐 모델을 제시하고, 컴포넌트 뱅크에 구축할 컴포넌트 개발을 위한 명세 방법의 개념 모델과 명세 단계를 제시하고 이를 비즈니스 응용 영역에 적용하여 개발한 명세화 접근 방법 및 개발 결과에 대하여 논한다.