• 대한지리학회지
• /
• 제41권2호
• /
• pp.188-194
• /
• 2006

3차원 위상 자료는 응급상황 처리와 3차원 네트워크 분석 등의 3차원 공간분석에 필수적으로 요구된다. 이 연구에서는 현재까지의 3차원 위상 데이터 모델에 대해 살펴보고, 건물을 설계하기 위해 사용되는 2차원 CAD 도면 데이터로 부터 3차원 위상적 노드-관계 데이터를 추출하는 방법을 개발하였다. 이 방법은 중심축 변환과 위상적 노드-관계 알고리듬들을 이용한 두 단계로 이루어진다. 첫번째 단계는 중심축 변환 알고리듬을 이용하여 CAD 데이터에서 폴리곤이나 이중 선으로 표현되는 벽으로부터 그 중심선을 생성하여 벽의 골격을 추출하는 것이다. 두번째 단계는 추출된 벽의 골격 자료를 이용하여 방을 3차원 노드로하고 방들간의 연결을 관계로하는 위상적 노드-관계 구조를 생성하는 것이다. 따라서, 그러한 연결들은 노드들간의 이웃성 또는 연결성을 표현하게 된다. 결론적으로, 이러한 변환방법으로 미시적 수준의 개별 건물들의 내부구조를 표현하는 3차원 위상구조 데이터는 건물의 도면 작성에 자주 사용되는 CAD 데이터로 부터 쉽게 생성될 수 있을 것이다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2010년도 추계학술대회 논문집
• /
• pp.865-866
• /
• 2010

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2008년도 정기 학술대회
• /
• pp.391-396
• /
• 2008

A level set based topological shape optimization using extended B-spline basis functions is developed for steady state heat conduction problems. The only inside of complicated domain is identified by the level set functions and taken into account in computation. The solution of Hamilton-Jacobi equation leads to an optimal shape according to the normal velocity field determined from the sensitivity analysis, minimizing a thermal compliance while satisfying a volume constraint. To obtain exact shape sensitivity, the precise normal and curvature of geometry need to be determined using the level set and B-spline basis functions. The nucleation of holes is possible whenever and wherever necessary during the optimization using a topological derivative concept.

• Bulletin of the Korean Chemical Society
• /
• 제25권2호
• /
• pp.253-259
• /
• 2004

Some new topological indices based on the distance matrix and Randic connectivity (as graph invariants) are proposed. The calculation of these indices is simple and they have good discriminating ability toward alkanes. Incorporating the number of carbon atoms to one of the calculated indices gives a highly correlating topological index (Sh index) which found to correlate with selected physicochemical properties of wide range of alkanes, specially, their boiling points. Most of the investigated properties are well modeled (with $r^2$> 0.99) by the Sh index. Meanwhile, the resulting regressions were compared with the results based on the well-established Randic and newly reported Xu indices and, in most cases, better results were obtained by the Sh index. Moreover, multiple linear regression analysis of the alkane properties via calculated indices gives highly correlating models with low standard errors.

• Journal of Power Electronics
• /
• 제16권4호
• /
• pp.1621-1628
• /
• 2016

Experiencing power declines when the secondary coil is at the middle position between two primary coils is a serious problem in segmented on-road charging systems with a single energized segmented primary coil. In this paper, the topological transformation of a primary circuit and a hierarchical compensation capacitor control are proposed. Firstly, the corresponding compensation capacitors and receiving powers of different primary structures are deduced under the condition of a fixed frequency. Then the receiving power characteristics as a function of the position variations in systems with a single energized segmented primary coil and those with double segmented primary coils are analyzed comparatively. A topological transformation of the primary circuit and hierarchical compensation capacitor control are further introduced to solve the foregoing problem. Finally, an experimental prototype with the proposed topological transformation and hierarchical compensation capacitor control is carried out. Measured results show that the receiving power is a lot more stable in the movement of the secondary coil. It is a remarkable fact that the receiving power rises from 10.8W to 19.2W at the middle position between the two primary coils. The experimental are in agreement with the theoretical analysis.

• 한국실내디자인학회논문집
• /
• 제19권4호
• /
• pp.22-30
• /
• 2010

Light has primary function to enlighten the darkness. However, as development and progresses in media has caused big change in our life, the range of usage and application of light is broadened. And these days, light is actively used as a communication tool in a space. This thesis is based on an idea that a new prospect of light is required and at the same time the theoretical foundation should be established to take active advantage of light. In Chapter two, analysis criteria are established to verify study hypothesis. The applied methodology is to analysis the contents based on literature review. Key words related light in space design are extracted and the frequency of those key words are quantitatively measured. Taking advantage of the result, the characteristics of light are divided into three categories, 'light as symbolic information', 'light as communication medium' and 'light as topological form'. In chapter three, analysis of cases is performed. The cases are selected based on space analyzing criteria established in Chapter two. Qualitative analysis is performed on the cases categorized into natural light and artificial light. Basic analysis elements are evaluated for each case. And each case is allocated to one of three categories, 'light as symbolic information', 'light as communication medium' and 'light as topological form'. Through this analysis, it is found that light in space has prevailing characteristics of 'light as symbolic information' and 'light as communication medium'.

• 한국농공학회논문집
• /
• 제57권6호
• /
• pp.59-68
• /
• 2015

Traditional structure analysis method is based on numerical matrix analysis to use the geometries consisting of the structure. The characteristics require a lot of computer memories and computational time. To avoid these weaknesses, new approach to analyze truss structure was suggested by adopting topological load redistribution method. The axial forces to be not structurely analyzed yet against outside loads were redistributed by using nodal equation of equilibrium randomly at each node without constructing global matrix. However, this method could not calculate the axial forces if structure is statically indeterminate due to degree of many indeterminacies. Therefore, to apply the method suggested in this research, all redundancies of truss structure were replaced by unit loads. Each unit load could make the deformation of a whole structure, and a superposition method was finally adopted to solve the simultaneous equations. The axial forces and deflections agreed with the result of commercial software within the relative error of 1 %, whereas in the case that the axial forces are relatively very smaller than others, the relative errors were increased to 2 %. However, as the values were small enough not to be considered, it was practically useful as a structural analysis model. This model will be used for structural analysis of truss type of large structure such as agricultural farming facility.

• 대한조선학회논문집
• /
• 제43권2호
• /
• pp.246-257
• /
• 2006

In the ship building industry, the generation of a structural analysis model, that is, a finite element model of a hull structure, has been manually performed by a designer and thus has required lots of time as compared with that of a mechanical part, because of many constraints, the complexity, and the huge size of the hull structure. To make this task automatic, a generation method of the structural analysis model is proposed through the reconstruction of the topological information of a hull structural model in this study. The applicability of the proposed method is demonstrated by applying it to the generation of the structural analysis model of a deadweight 300,000ton VLCC(Very Large Crude oil Carrier).

• 국제학술발표논문집
• /
• The 9th International Conference on Construction Engineering and Project Management
• /
• pp.269-276
• /
• 2022

The robustness of a supply chain (i.e., the ability to cope with external and internal disruptions and disturbances) becomes more critical in ensuring the success of a construction project because the supply chain of today's construction project includes more and diverse suppliers. Previous studies indicate that topological features of the supply chain critically affect its robustness, but there is still a great challenge in characterizing and quantifying the impact of network topological features on its robustness. In this context, this study aims to identify network measures that characterize topological features of the supply chain and evaluate their impact on the robustness of the supply chain. Network centrality measures that are commonly used in assessing topological features in social network analysis are identified. Their validity in capturing the impact on the robustness of the supply chain was evaluated through an experiment using randomly generated networks and their simulations. Among those network centrality measures, the PageRank centrality and its standard deviation are found to have the strongest association with the robustness of the network, with a positive correlation coefficient of 0.6 at the node level and 0.74 at the network level. The findings in this study allows for the evaluation of the supply chain network's robustness based only on its topological design, thereby enabling practitioners to better design a robust supply chain and easily identify vulnerable links in their supply chains.

• 정보과학회 논문지
• /
• 제43권7호
• /
• pp.812-819
• /
• 2016

본 논문에서는 기존의 영상분할에서 발생하는 초기값 배정문제와 영상분할 가능여부를 확인할 수 있는 방법에 대한 이론적 근거를 분석하고 제시한다. 본 논문의 앞 부분에서는 위상수학의 이론에 근거한 수학적 논증을 바탕으로 적절한 초기값 배정의 대한 위상적 근거와 방법론을 제시한다. 이어서 위상수학의 분리공리 이론에 근거하여 영상이 영역 분할되기 위한 최소의 위상조건을 확인하고 해당 조건을 이용하여 영상분할을 위해 사용된 모델의 유효성을 검증하는 방법론을 제시한다. 즉, 본 논문은 기존의 통계적 분석과 달리, 위상적 분석을 통해 영상 영역 분할의 수학적 근거를 제시한 것에 그 특징이 있다. 마지막으로 기존의 가우시안 랜덤 필드 모델 기반 영상 분할에 본 논문에서 제시한 이론과 방법론을 적용하여 가우시안 랜덤 필드 모델의 유효성을 확인한다.