• 한국자동차공학회논문집
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• 제10권1호
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• pp.187-194
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• 2002

It has been reported that cracks in mechanical joints is generally under mixed-mode and there is critical inclined angle at which mode I stress intensity factor becomes maximum. The crack propagates in arbitrary direction and thus the prediction of crack growth path is needed to provide against crack propagation or examine safety. In order to evaluate the fatigue life of cracks in mechanical joints, horizontal crack normal to the applied load and located on minimum cross section is major concern but critical inclined crack must also be considered. In this paper mixed-mode fatigue crack growth test is performed far horizontal crack and critical inclined crack in mechanical joints. Fatigue crack growth path is predicted by maximum tangential stress criterion using stress intensity factor obtained from weight function method, and fatigue crack growth rates of horizontal and inclined crack are compared.

• 한국정보과학회논문지:시스템및이론
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• 제29권11호
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• pp.634-639
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• 2002

최단 경로 탐색 알고리즘 (Shortest Path Algorithm)은 출발지에서 목적지에 이르는 여러 경로 중에서 가장 경제적이고 효율적인 경로를 찾는 알고리즘으로 레이블링 기법에 기초하고 있다. 레이블링 기법에는 레이블 고정(Label-Setting) 기법과 레이블 수정 (Label-Correcting) 기법이 있다. One-to-One 최단 경로 탐색 알고리즘에서 레이블 고정 기법이 빠르다고 알려져 왔으나 최근 연구에서 대용량 도로 데이터에 대한 실험을 통해 레이블 수정이 레이블 고정보다 탐색 씨간이 빠름을 보였다[1,2]. 레이블 수정 기법 중에서 가장 속도가 빠른 것은 그래프 성장 (Graph Growth) 알고리즘인데, 이 알고리즘은 One-to-All 방식을 사용하고 있으므로 One-to-One 최단 경로 탐색에는 적합하지 않다. 본 논문에서는 One-to-One 방식을 사용하는 새로운 알고리즘을 제안하였고, 실험결과 그래프 성장 알고리즘의 성능에 비해 새로 제안된 알고리즘의 성능이 30~40 향상되었음을 알 수 있었다.

• 한국콘텐츠학회논문지
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• 제20권7호
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• pp.602-617
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• 2020

자유시장 경제를 근간으로 한 이윤주도 성장전략의 대안으로 논의되고 있는 소득주도성장 전략은 정부 부문의 적극적인 개입이 필요하므로 정부지출의 효용성이 중요한 요인으로 인식되고 있다. 본 논문에서는 지난 수십 년 동안 분배체계에 의한 소득주도성장 정책을 수행해 온 북유럽과 남미 국가, 그리고 한국을 대상으로 정부지출과 소비지출의 경제적 관계를 규명하고, 이 결과를 바탕으로 소득주도성장 경로를 논의하였다. 지출 국민소득에 의한 구조방정식을 설정하고 일반화된 선형모형(GLMs)에 의해 추정한 실증분석 결과에 의하면, 북유럽 국가와 한국의 경우 정책적 효과가 크지는 않지만, 소득주도성장 정책으로 국민소득을 증가시킬 수 있는 것으로 나타났다. 그러나 남미 국가는 소득주도성장 정책의 운용이 불안정할 뿐만 아니라 정책효과도 나타나지 않는 것으로 분석되었다. 또한, 소득주도성장 정책을 수행하는 과정에서 저소비 계층보다는 중간소비 계층을 활용한 경로가 더욱 효율적인 것으로 나타났다. 결과적으로 소득주도성장 정책은 지속 가능한 성장 전략이라기보다는 보완적 기능을 수행하는 정책으로 활용하는 것이 바람직할 것이다.

• 산업경영시스템학회지
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• 제43권1호
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• pp.79-86
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• 2020

The effects of R&D investment on innovation such as patents and intangible assets, and the effect on the corporate performance such as revenue and profit growth, were analyzed using path analysis. In particular, this study compared and analyzed the performances of non-cooperative R&D and cooperative R&D. The results of this study are summarized as follows. First, R&D investment has a significant impact on innovation performance. This supports the existing research results. Second, patents have a significant impact on intangible asset growth. Third, in the case of corporate groups carrying out cooperative R&D, intangible asset growth forms a significant causal relationship with revenue growth. Fourth, in case of cooperative R&D, intangible asset growth has a significant mediating effect between patent and revenue growth. Like the existing research, the results of this research support the innovation performance of R&D investment. It also supports the existing argument that the results of cooperative R&D are more favorable to increase corporate value. However, unlike the existing research, we found a path leading to increased revenue through patents and intangible assets, and confirmed that such a path is likely to be achieved through cooperative R & D rather than internal R&D.

• 한국시스템다이내믹스학회:학술대회논문집
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• 한국시스템다이내믹스학회 2000년도 하계학술대회발표논문집
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• pp.29-45
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• 2000

The purpose of this paper is understanding the dynamics of knowledge based industries in Korea and suggesting policy recommendations for supporting those industries. Following KIETs (1999) definition of knowledge intensity, this paper classified industries in Kyung Ki Province according to several knowledge indicators including R＆D activity and human capital content. Having classified industries, this paper investigates growth dynamics of knowledge based industries in Kyung-Ki Province. Based on surveys on some 280 knowledge based industries in Kyung-Ki province, growth path of those industries were identified using path analysis. Using the growth path and coefficient identified by the analysis, system dynamics model was build to simulate dynamics of knowledge based industries in Kyung-Ki province. With the model, further analysis was made to investigate some policy measures that can promote knowledge based industries.

• 대한조선학회지
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• 제25권4호
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• pp.39-46
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• 1988

The purpose of this paper is to apply the boundary element method to predict the crack growth path. The quarter point element with traction singularity at the crack tip is applied to compact tension type specimens and two inclined slit problems under compression load. The maximum stress criterion which was originally derived for the crack initiation is extended to the analysis of the crack propagation. The predicted crack paths with 1/4 crack growth increment of initial crack length agree quite well with experimental results. It is found that the computed crack path of the boundary element analysis is not mainly affected by the crack increment length.

• 한국컴퓨터정보학회논문지
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• 제12권6호
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• pp.131-137
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• 2007

전파가 미치지 않는 3차원 지형에서의 음영공간을 항공기가 안전하게 목적지까지 비행하는 최단 경로를 구하고자 하는 것이다. 여기서 비교적 넓은 음영공간을 다각형 형태의 볼록 다각형으로 분할하고, 분할된 볼록 다각형 내에서는 가중치 값에 따라 중간목적지까지의 경로를 찾고, 그 중간목적지를 시작점으로 하여 인접한 다각형에서 다시 목적지를 찾아가는 과정을 분할된 다각형 내에서 반복해서 최종 목적지까지의 최단 경로를 찾아가는 방법을 제안하였다. 구현은 3차원 실지형 상에서 전파가 미치지 않는 음영공간상에 Graph Growth 알고리즘의 임계값을 적용한 수정된 알고리즘을 이용하여 최단 경로를 탐색하였다. 실험에 의해 본 논문에서 제안한 방법이 효과적인 비행 궤적을 생성하였다.

• STI Policy Review
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• 제1권1호
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• pp.93-109
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• 2010

Over the last decade, some Korean enterprises have emerged to become global players in their specialized products. How have they achieved such tremendous technological progress in a short period of time? This paper explores that question by examining the characteristics of technological innovation activities at major Korean enterprises. The paper begins with a brief review of the stages of economic growth and science and technology development in Korea. Then, the existing literature, explaining the Korean innovation model, is analyzed in order to establish a new framework for the Korean innovation model. Specifically, Korean firms have experienced three sequential phases, and thus, the Korean model, at the firm level, can be coined as "path-following," "path-revealing," and "path-creating." Then, the stylized facts in the first phase (path-following) and the second phase (path-revealing) are discussed, in the context of empirical evidence from the areas of memory chips, automobiles, shipbuilding, and steel. In terms of technology development, the Korean model has evolved as "collective learning" in the first phase, "collective recombination" of existing knowledge and technology in the second phase, and is assumed as "collective creativity" in the third phase. Ultimately, all three can be classified as "collective creation". Korean firms now face a transition in the modes of technological innovation in order to efficiently implement the third phase. To achieve remarkable progress again, as they did in the past, and to sustain the growth momentum, Korean firms should challenge new dimensions such as creative technological ideas, distinctive technological capabilities, and unique innovation systems -- all of which connote 'uniqueness'. Finally, some lessons from the Korean technological innovation experience are addressed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.1133-1137
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• 1995

This paper presents a numerical method of the global search for an optimal geometric path for a manipulator arm amid obstacles. Finite term quintic B-splines are used to describe an arbitrary point-to-point manipulator motion with fixed moving time. The coefficients of the splines span a linear vector space, a point in which uniquely represents the manipulator motion. All feasible geometric paths are searched by adjusting the seed points of the obstacle models in the penetration growth distances. In the numerical implementation using nonlinear programming, the globally optimal geometric path is obtained for a spatial 3-link(3-revolute joints) manipulator amid several hexahedral obstacles without simplifying any dynamic or geometric models.

• 한국정밀공학회지
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• 제18권10호
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• pp.109-115
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• 2001

The compliance approach to the problem of load sharing between a cracked plate and multiple plate used to bridge the crack. The theory is validated by using calculated stress intensity factors for the multiple load path plate to reduce experimentally observed growth rate to a common base. Calculations are them made on the effect of multiple load path plate width on fatigue crack retardation in order to demonstrate the predictive capability of the technique.