• Journal of Korean Association for Spatial Structures
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• v.11 no.1
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• pp.77-85
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• 2011

In this study, micro genetic algorithm is used to find an optimum cross section of grid structures with pretension. Design optimization of trusses consists of arriving at optimum sizes of cross-section and prestressing force parameters, when weight of the truss is minimum, satisfying a set of specified constraints. The present approach is verified by ten-bar truss example showing good agreements with previous results. Features of the proposed method, which help in modeling and application to optimal design of pretensioned truss structures, are demonstrated by solving a problem of seventy two bar truss structures. The minimum weight design of seventy two bar truss is performed for various magnitudes of pretension and optimal prestressing forces are also found for various configurations of pretensioned truss structures.

• Journal of Korean Association for Spatial Structures
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• v.6 no.1 s.19
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• pp.75-82
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• 2006

The single layer latticed dome is very sensitive on the slenderness ratio and half open angle of the elements, load condition, and the connection type because it is organized by a lot of thin elements, so we have to use the geometrically nonlinear buckling load when the buckling of the structures is analyzed. But, it is very difficult to design the single layer latticed domes considered all renditions. Therefore the purpose of this paper is to propose the appropriate design method of the single layer latticed dome considered the geometrically nonlinear buckling load in base of the linear buckling load by the eigenvalue analysis.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.3
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• pp.371-379
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• 2011

In this paper, we propose a development methodology of interactive stereoscopic image display system. In our case, we consider a multiple touch recognition technique as the interaction method. That's because we want to guarantee multiple user access and interaction to the content without any restriction. In this case, however, some restrictions are occurred on account of the distance between display and participants. For this reason, this paper propose an invisible interaction surfaces which are generated in the air. This surface is utilized as interaction medium instead of the display wall. We also present an effective way to generate and edit interactive stereoscopic images based on Game Engine.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.523-529
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• 2023

The aim of this study was to analyze the potential for timber harvesting in the Hongchoen Garisan Leading Forest Management Complex in the national forests, and to suggest an optimal target yield for sustainable timber harvesting. The potential for timber harvesting was assessed by analyzing the area available for timber harvesting using GIS spatial analysis, but excluding areas with a slope of more than 40° (topographical constraints), areas within 30 m on both sides of streams (environmental constraints), and areas more than 300 m away from forest roads (technical constraints). The analysis identified 3,298 ha (49%) of the total complex area of 6,679 ha as available for timber harvesting, yielding a potential harvesting volume of 608,613 m³. In the case of coniferous plantations, the potential harvesting volume was 409,721 m³, which was a very high level that accounted for 67.3% of the total. We also conducted an optimization analysis to minimize the differences in area between age classes, while maintaining sustainable timber harvesting for the next 50 years. An annual average of 41.9 ha (7,988 m³) was determined to be the optimal timber yield, and in this case, it was possible to convert the age class structure to a more stable structure after 50 years.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.2
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• pp.127-140
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• 2002

In a spatial database system, the semantic integrity should be supported for maintaining the data consistency. In the real world, spatial objects In boundary layer should always meet neighbor objects, and they cannot hold the same name. This characteristic is an implied concept in real world. So, when this characteristic is disobeyed due to the update operations of spatial objects, it is necessary to maintain the integrity of a layer. In this thesis, we propose a spatial-operation-trigger for supporting the integrity of spatial objects. The proposed method is defined a spatial-operation-trigger based on SQL-3 and executed when the constraint condition is violated. A spatial-operation-trigger have the strategy of execution. Firstly, for one layer, the spatial and aspatial data triggers are executed respectively. Secondly, the aspatial data trigger for the other layers is executed. Spatial-operation-trigger for one layer checks whether the executed operation updates only spatial data, aspatial data, or both of them, and determines the execution strategy of a spatial-operation-trigger. Finally, the aspatial data trigger for the other layers is executed. A spatial-operation-trigger is executed in three steps for the semantic integrity of the meet-property of spatial objects. And, it provides the semantic integrity of spatial objects and the convenience for users using automatic correcting operation.

• Convergence Security Journal
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• v.18 no.2
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• pp.41-47
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• 2018

Theorists of war have often used Clausewitz's trinity theory as a framework for analyzing war strategies and histories. Heretofore, studies on cyber warfare have focused primarily on laws, policies, structuring organizations, manpower, and training pertaining to preparing the cyberspace for war. Currently, studies highlighting the comparative characteristics of war in cyberspace, how it differs from conventional warfare, and analytical frameworks for understanding war in cyberspace are rare. Using Clausewitz's trinity theory, this paper interprets the essence of war from the perspectives of (1) Intellect, (2) Bravery, and (3) Passion, to propose an analytical model for understanding war in cyberspace, one that factors in the intrinsic qualities and characteristics of cyberspace under spatial and temporal constraints. Furthermore, this paper applies the aforementioned analytical model to the Iraq War and concludes with a theoretical illustration that cyber warfare played a significant role in winning the war.

• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.407-410
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• 2000

본 논문에서는 3차원 웨이블릿 부호화 방식으로 압축된 영상 시퀸스를 정칙화 기반 영상복원 방법으로 후처리하는 알고리듬을 제안한다. 우선, 웨이블릿 압축 시스템을 적절한 영상 열화 시스템으로 모델화한다. 그리고, 시간축에 관하여 프레임 간의 같은 위치에 있는 각 픽셀에 대하여 복원을 수행한다. 그 다음으로 2차원 영상 신호에 대하여 복원을 수행하는데. 즉 웨이블릿 변환 계수 정보를 이용하여 영상 및 시간 정보를 여러 스케일의 에지로 분류한 다음, 에지의 방향에 따른 적응적인 제약조건을 사용한다. 이는 각각의 에지 방향에 적합한 고주파 성분을 유지하고, 신호의 각 특성에 적합한 적응적인 정칙화 매개변수를 적용한다. 마지막으로 시간 축에서의 복원과 그것에 이어지는 적응적인 공간 복원에 대한 실험 결과를 보여준다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.11a
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• pp.523-526
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• 2005

계통발생학적 분석기법은 서열의 유사성을 비교하여 이들의 유연관계를 알아내는 것으로, 각각의 관계를 시각적으로 표현하는 것이 매우 중요하다. 일반적으로 2차원 계통수를 사용한다. 그러나 2차원으로 시각화했을 때 서로 유사성이 높은 OTU(Operational Taxonomic Unit)들을 서로 멀리 떨어뜨려 놓는 경우도 생기게 된다. 이 논문에서는 이러한 점을 보완하고자 3차원 공간에 OTU들을 배치시키기 위한 2단계 좌표 배치 기법을 제안한다. 단계는 유클리디안 거리를 3차원 좌표로 변환하는 것이다. 1단계 방법은 서열의 비교 순서에 영향을 받기 때문에 2단계를 통해 유전자 알고리즘 기법을 적용하여 보다 적절한 좌표를 찾는다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.1
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• pp.146-153
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• 2004

This paper presents the method for the placement and operation of dispersed generator systems(DGs) using fuzzy goal programming in distribution systems. For the placement and operation of DGs the problem is formulated with reduction of search spaces and flexibility of system situations. Especially, the original objective function and constraints are transformed by fuzzy goal programming to evaluate their imprecise nature for the criterion of power loss minimization, the number or total capacity of DGs and the bus voltage deviation, and then solve the problem using genetic algorithm.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.499-502
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• 2005

국가GIS사업 및 관련사업을 통해 다양한 지리정보가 생산되었으며, 다양한 분야의 사용자에 의해 구축 활용되는 지리정보의 특성에 따라 전국에 분포되어 관리되고 있다. 이러한 지리정보가 사장되지 않고 목적에 맞게 효율적으로 활용되기 위해서는 다양한 콘텐츠 확보가 이기종간 공동활용이 선행될 필요가 있다. 따라서 본 연구에서는 서로 다른 시스템 환경에서 지리정보를 연계하여 활용할 수 있도록 카탈로그 모듈, 브로커 모듈, 맵브라우저 모듈, 지리정보등록 모듈 등을 구현하고 Informix, Oracle, GMS, ZEUS 등 여러 가지 조합이 도출될 수 있는 시스템을 대상으로 검증실험을 하였다. 본 연구에서 도출된 모듈을 적용하여 데이터 연계의 제약조건인 DMBS, 공간DBMS 영향을 최소화함으로써 지리정보공유 활성화에 기여할 수 있다.