• Architectural research
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• 제11권2호
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• pp.43-49
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• 2009

Since the late 1980s, the schedule technique applied to the construction industry around the world has rapidly changed from the traditional ADM (Arrow Diagramming Method) to the PDM (Precedence Diagramming Method) technique. The main reason for this change is to overcome the limits and inconveniences of the traditional ADM technique. The time-cost trade-off is one of the core scheduling techniques to establish the best optimized combination plan in terms of a relationship between the cost and schedule. However, most of the schedule-related textbooks and research papers have discussed and proposed applications of a time-cost trade-off technique based only on the Finish to Start relationship. Therefore, there are almost no consideration and discussion of problems or restrictions that emerge when the time-cost trade-off technique is applied to the PDM network that has overlapping relationships. This paper proposes the lead-time adjustment method as a methodology for overcoming some restrictions that are encountered when the time-cost trade-off technique is applied to the overlapping relationships of the PDM network.

• 한국CDE학회논문집
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• 제17권4호
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• pp.294-302
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• 2012

Process mining is a useful methodology that can be used for extracting user patterns in log files in order to discover efficient or inefficient processes in organizations. In general, it is used to find and reduce differences between pre-defined processes and actually executed processes in an organization. In this paper, we propose a method to improve processes in PDM/PLM systems based on process mining. In order to improve and detect the inefficient processes, we gathered event logs from PDM/PLM systems and derived process models using several process mining techniques such as ${\alpha}$-algorithm mining, heuristics mining, and fuzzy miner. By comparing original process models with process mining results, it is possible to detect differences between predefined processes and real ones; thereby we can build improved process models for future application.

• 한국CDE학회논문집
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• 제19권2호
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• pp.103-110
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• 2014

Engineering changes are indispensable engineering and management activities for manufactures to develop competitive products and to maintain consistency of its product data. Analysis of engineering changes provides a core functionality to support decision makings for engineering change management. This study aims to develop a method for analysis of engineering changes based on On-Line Analytical Processing (OLAP), a proven database analysis technology that has been applied to various business areas. This approach automates data processing for engineering change analysis from product databases that follow an international standard for product data management (PDM), and enables analysts to analyze various aspects of engineering changes with its OLAP operations. The study consists of modeling a standard PDM database and a multidimensional data model for engineering change analysis, implementing the standard and multidimensional models with PDM and data cube systems and applying the implemented data cube to core functions of engineering change management, the evaluation and propagation of engineering changes.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.53-59
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• 2003

제조업 경쟁력 확보의 일환으로 최근 들어 각 기업에서 정보 기술의 활용이 급격히 증가하고 있는데 이 중에서 특히 제품 설계 단계에서는 PDM 시스템이, 생산 단계에서는 ERP 시스템이 널리 사용되고 있다. 제품 수명 주기의 초기 단계인 설계 단계에서 생성되거나 사용되는 많은 종류의 데이터는 생산 단계에서도 똑같이 사용되기 때문에 PDM 시스템과 ERP 시스템 간의 원활한 데이터 흐름은 전체 생산성 향상에 필수적인 요소라 하겠다. 본 연구에서는 PDM/ERP 시스템 간의 원활한 데이터 연동 환경을 개발하기 위래 연동대상 데이터 분석을 통해 필요한 기능적 요구사항을 도출하고 이를 공정 계획 시스템을 기반 구조로 하는 시스템으로 구현하고 항공기생산 과정에 적용하였다. 이러한 개발을 통해 공정 계획 작업 기간이 단축되고 데이터 정확도가 향상되는 효과를 볼 수 있었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.307-310
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• 2001

In this paper, development of TIM Module for constructing PDM will be introduced. Technical information relevant product data influences cost, quality, precision and productivity. One of the very important feature of product data is organizing not by oneself but very closed to many technical information such as document, file, image and analysis sheet. To manage various technical information, several kinds of management system are used in multi level of production system. PDM and TIM systems are being developed for suitable purpose and are in need of Network technology, Information Technology, Database, sharing and distributing information. Developed TIM system is based on Web environment. By using this system, we can manage systematic technical information and reduce cost for constructing PDM system. And also we will put to practical use another technical information management system for mold plant.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1061-1062
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• 2008

The project of advanced urban transit system (AUTS)development is developing the advanced vehicle and the core technologies for the cost down by system change, the transport safety and the environmental friendliness and the improvement of passenger service. The product data management(PDM) system is installed for management of each project. Various data and informations producted from each project are made for database. We developed the product data management system for advanced urban transit system. In past, it was AUTS-PDM of C/S version. Now, we develop AUTS-PDM of Web version.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.419-422
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• 2002

This paper compares PDM and PWM for single phase switched reluctance motor for vacuum cleaner. Generally, PWM control scheme Is preferred because of small torque ripple compared with PDM control scheme. However, as the motor speed of the vacuum cleaner is above 20,000[rpm], the torque ripple is not problem any more. PDM control scheme is better than PWM control scheme considering loss of power device and EMI.

• 대한기계학회논문집A
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• 제31권2호
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• pp.260-268
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• 2007

Demand for the use of 3D CAD DMU systems over the Internet environment has been increased. However, transmission of commercial 3D kernels has delayed the communication effectiveness due to the kernel size. Light weight CAD geometric kernel design methodology is required for rapid transmission in the distributed environment. In this paper, an assembly data structure suitable for the top-down and bottom-up assembly models has been constructed. Part features are stored without a hierarchy so that they are created and saved in no particular order. In particular, this paper proposes a new assembly representation model, called multi-level assembly representation (MAR), for the PDM based assembly DMU system. Since the geometric kernel retains assembly hierarchy and topological information, it is applied to the web-viewer for the PDM based DMU system. Effectiveness of the proposed geometric kernel is confirmed through various case studies.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.75-78
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• 2000

This paper is estimated to enhance yield improvement and device reliability using PDM(plasma damage monitoring) system capable of in-suit detection about plasma nonuniformity. PDM Tool is the non-contact method of wafer and surface potential electrode(kelvin probe). Its tool measures Vox(oxide barrier) with charge created by plasma. It's possible to inspect the wafer damage generated by plasma charge and analysis of in-situ monitoring data. we obtained the good data which is continuously prevented from plasma damage using its tool for 10weeks. This tool is contributed to preventive steps contemporaneously inspecting the difference of inter-chamber.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.176-177
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• 2005

PDMS는 생명공학 분야에서 중요한 기술적 폴리머이다. Nd:YAG레이저의 4고조파 ($\lambda$=266nm, pulse) 레이저를 사용하여 표면 처리를 하여 PDMS 표면의 습윤성과 접착성의 향상됨을 확인하였다. 식각한 PDMS는 샘물체의 미세회로에 사용될 수 있다. 본 논문은 레이저 빔의 주사속도를 변화시키며 PDMS를 레이저로 식각하며 PDMS의 식각 특성을 연구한다 식각 특성을 의존성이 가장 효과적인 주사 속도에 대한 의존성을 규명하고자 스테이지 컨트롤러의 속도를 변화시키며 실험하였다. 그리고 최적의 레이저 출력값을 알아내려고 레이저 출력값을 조절하며 실험 하였다. 단차측정기(알파스템)을 이용하여 식각형상과 식각 효율 등을 분석하였다.