• 대한전기학회논문지
• /
• 제34권8호
• /
• pp.308-316
• /
• 1985

This paper proposes an analytic tool for long-term generation expansion planning based on the maximum principle. Many research works have been performed in the field of generation expansion planning. But few works can be found with the maxinmum principle. A recently published one worked by professor Young Moon Park et al. shows remarkable improvements in modeling and computation. But this modeling allows only thermal units. This paper has extended Professor Park's model so that the optimal pumped-storage operation is taken into account. So the ability for practical application is enhanced. In addition, the analytic supply-shortage cost function is included. The maximum principle is solved by gradient search due to its simplicity. Every iteration is treated as if mathematical programming such that all controls from the initial to the terminal time are manipulated within the same plane. Proposed methodology is tested in a real scale power system and the simulation results are compared with other available package. Capability of proposed method is fully demonstrated. It is expected that the proposed method can be served as a powerful analytic tool for long-term generation expansion planning.

• 한국기계가공학회지
• /
• 제16권3호
• /
• pp.1-8
• /
• 2017

Tool path generation is a part of process planning in 3D printing. This is done before actual printing by a computer rather than an AM machine. The mesh geometry of the 3D model is sliced layer-by-layer along the Z-axis and tool paths are generated from the sliced layers. Each 2-dimensional layer can have two types of printing paths: (i) shell and (ii) infill. Shell paths are made of offset loops. During shell generation, twists can be produced in offset loops which will cause twisted tool paths. As a twisted tool path cannot be printed, it is necessary to remove these twists during process planning. In this research, An algorithm is presented to remove twists from the offset loops. To do so the path segments are traversed to identify twisted points. Outer offset loops are represented in the counter-clockwise segment order and clockwise rotation for the inner offset loop to decide which twisted loop should be removed. After testing practical 3D models, the proposed algorithm is verified to use in tool path generation for 3D printing.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2002년도 ICCAS
• /
• pp.55.6-55
• /
• 2002

Huafei Liao is a graduate student of the Automation department in Tsinghua University, China. His research involves computer-aided process planning, 3D CAD/CAM, virtual reality, and feature recognition.

• Journal of Construction Engineering and Project Management
• /
• 제3권2호
• /
• pp.1-12
• /
• 2013

Research indicates that good front-end planning (FEP) results in the achievement of higher levels of project performance. By facilitating collaboration among stakeholders in diverse locations with the use of workflow-enabled processes, such pressures can be reduced, and the overall process and results of FEP can be improved. With these goals, a front-end planning tool (FEPT) has been developed as support for owners and major contractors who are engaged in front-end planning. This paper presents the new FEPT and describes how it has been used for construction megaprojects in the nuclear power, oil and gas, and mining industries. The paper begins with the definitions related to and an explanation of the general process for implementing and applying the FEPT and then describes and analyzes how the FEPT was applied in case study projects in order to test its validity. The results indicate that the FEPT increases the efficiency and effectiveness of front-end planning for the megaprojects studied and that it has the potential to produce similar results for other megaprojects.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
• /
• pp.1078-1083
• /
• 1992

Extracting the process planning information from the CAD data is the key issue in integrated CAD/CAM system. In this paper, we develop algorithms for extracting the shape and setup configuration for NC machining of prismatic parts. In determining the workpart shape, the minimum-enclosing condept is applied so that the material waste is minimized. To minimize the number of setups, feature based algorithm is developed considrint the part shape, tool shape, and tool approach direction. The validity and effectiveness of the developed algorithms were tested by computer simulations.

• 대한기계학회논문집A
• /
• 제27권8호
• /
• pp.1418-1425
• /
• 2003

In CAD systems, a surface to be machined is expressed by a series of curves, such as B-spline, Bezier and NURBS curves, which compose the surface and then in CAM systems the curves are divided into a large number of line or arc segments. These divided movement commands, however, cause many problems including their excessive size of NC data that makes almost impossible local adjustment or modification of the surface. To cope with those problems, the necessity of real-time curve or surface interpolators was embossed. This paper presents an efficient real-time tool-path generation method fur interpolation of NURBS surfaces in CNC machining. The proposed tool-path generation method is based on an improved iso-scallop strategy and can provide better precision than the existing methods. The proposed method is designed such that tool-path planning is easily managed in real-time. It proposed a new algorithm for regulation of a scallop height, which can efficiently generate tool-paths and can save machining time compared with the existing method. Through computer simulations, the performance of the proposed method is analyzed and compared with the existing method in terms of federate, total machining time and a degree of constraint on the scallop height.

• 한국건설관리학회:학술대회논문집
• /
• 한국건설관리학회 2001년도 학술대회지
• /
• pp.410-415
• /
• 2001

Earned Value Management System(EVMS)은 최근 건설 프로젝트를 관리하는데 매우 유용한 도구로 인식되고 있으며, 정부차원에서 적극적으로 도입을 검토하고 있는 선진 관리기법이다. 이 EVMS는 미국방성에 의해 1960년대부터 프로젝트의 효율적인 관리를 위해 개발된 C/SCSC에 기반을 두고 있으며, 국내외에서 정부발주공사뿐만 아니라 민간발주의 건설프로젝트를 관리하는 도구로 활용하기 위해 연구가 활발하게 진행되고 있다. 본 연구에서는 공정관리 프로그램과 복합작업모델(Workpackaging model)을 바탕으로 건설프로젝트의 EV계획과 분석이 효과적으로 이루어질 수 있도록, 제조업의 재고관리모형중의 한 형태로 조립제품의 자원운영계획을 수립하는데 우수한 기법으로 알려진 MRP기법을 활용하여 EVMS가 건설현장에서 보다 용이하고, 효과적으로 활용될 수 있는 방안을 제시하고자 한다.

• 소프트웨어공학소사이어티 논문지
• /
• 제26권4호
• /
• pp.77-92
• /
• 2013

소프트웨어 프로젝트 계획 생성 과정은 (1)프로젝트를 수행하기 위한 작업 구조(WBS)를 작성하고, (2)각 작업에 필요한 공수를 예측한 뒤, (3)작업에 인력을 할당하여, (4)전체 일정을 예측하는 과정으로 이루어진다. 프로젝트의 규모가 커질수록 가능한 작업 구조, 공수, 인력 할당의 조합의 수가 급격히 많아지며 이에 따라 프로젝트 계획 생성 과정의 복잡도가 매우 높아지게 된다. 따라서 이를 지원하기 위한 프로젝트 계획 생성 지원 기법이 필요하다. 본 연구에서는 실무 전문가 그룹과의 논의를 통해 소프트웨어 프로젝트 계획 생성 지원 기법에서 고려해야 할 여러 실무 요구사항들을 도출했다. 도출된 실무 요구사항을 고려하여 개발된 프로젝트 계획 생성 지원 도구 APP(Automatic Project Planner)는 개발 조직의 과거 지식 데이터를 활용한 공수 예측을 지원하며, 실무 이슈가 고려된 자동 인력 할당을 제공한다. 본 도구를 통해 합리적이고 현실적인 프로젝트 계획의 기반을 마련할 수 있다.

• 한국정밀공학회지
• /
• 제23권3호
• /
• pp.118-124
• /
• 2006

The characteristic of sheet metal process is the few loss of material during process, the short processing time and the excel lent price and strength. The sheet metal process with above characteristic is common used in industrial field, but in order to analysis irregular field problems the reliable and economical analysis method is demanded. Finite element method is very effective method to simulate the forming processes with good prediction of the deformation behavior. Among Finite element method, the static-implicit finite element method is applied effectively to analyze real-size auto-body panel stamping processes, which include the forming stage. In this paper, it was focused on the drawing ability factors on auto-body panel stamping by AUTOFORM with using tool planning alloy to reduce law price as well as high precision front Design Optimization of die. According to this study, the results of simulation will give engineers good information to access the Design Optimization of die.

• 한국실내디자인학회논문집
• /
• 제17권5호
• /
• pp.123-132
• /
• 2008

It would be investigated how to take advantage of and structure color as form creation of modern architecture and tool of conception. Through this study, it was analyzed that color was introduced actively in the beginning stage of form creation as an image, as collection of data and analysis system, and as creation system of diagram. Also, it was used from the model making stage with experimental device, and was handling to experimental system of various materials and substances. Therefore, with the characteristics of color's originality, color was dealt to space creation system by tool from the process-oriented thought and had given the absolute value in form creation process. Meaning is that the color to be used as a tool in the planning contains a lot of possibilities and values in the architecture planning. Therefore the development of the system without initial planning of overall color scheme could affect the harmony and integration of the developed architecture. And the system could loose many vital concepts in the creation of the form. In execution of thinking process through the color, it'll be ensured that we can acquire the much better and more various result.