• Title/Summary/Keyword: change order (design change)

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High-Order QAM에 적합한 반송파 동기회로 설계 - II부. 자동모드전환시점 검출기 및 평균모드전환회로를 적용한 Gear-Shift PLL 설계 및 성능평가 (Design of Carrier Recovery Circuit for High-Order QAM - Part II : Performance Analysis and Design of the Gear-shift PLL with ATC(Automatic Transfer-mode Controller) and Average-mode-change Circuit)

  • 김기윤;김신재;최형진
    • 대한전자공학회논문지TC
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    • 제38권4호
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    • pp.18-26
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    • 2001
  • 본 논문에서는 극성 판단(Polarity Decision) PD를 이용하여 모드 변환과 루프이득(Loop Gain)의 변환시점을 자동적으로 검출해 주는 ATC(Automatic Transfer mode Control)알고리즘을 설계하고 모드 전환시 안정적으로 주파수 오프셋을 추정하는 평균방식 Gear-shift PLL을 설계하였다. 제안하는 모드 전환 시점 검출 알고리즘인 ATC 알고리즘은 종전의 QPSK방식에 적용되던 Lock Detector 알고리즘보다 구현이 매우 간단하며 정확하게 모드 전환시점을 검출한다. 또한 Shift Register에 저장했던 주파수 추정 값들을 평균하는 평균전환방식은 모드 전환시 낮은 주파수 추정 에러값으로 다음 모드에서의 빠른 추적 성능을 가능하게 한다. 본 논문에서 제안하는 알고리즘은 적은 회로 면적과 고속 처리가 가능하도록 설계되어 ASIC 설계에 매우 유용하다. 아울러 본 논문에서는 극성판단 PD를 적용하여 위상 포착 및 추적 성능평가를 수행하고 성좌도(constellation)를 각 모드별로 분석하였다.

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국제연합개발계획의 기후변화 적응 정책 체계 소개 (UNDP's Adaptation Policy Framework for Climate Change)

  • 신임철;이은정;권원태;임재규
    • 대기
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    • 제15권1호
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    • pp.59-68
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    • 2005
  • United Nations Development Programme (UNDP) introduced the Adaptation Policy Framework (APF) to support the developing countries in order to help to make adaptation policy and strategy to climate change. This study provides the summary of the APF and will help for preparing policy regarding the impact of climate change and its adaptation. APF consists of five basic and two cross-cutting steps. Five basic steps are made of (a) defining project scope and design, (b) assessing current vulnerability and adaptation, (c) assessing future climate-related risks, (d) developing an adaptation strategy, and (e) continuing the adaptation process. Cross-cutting steps consist of engaging stakeholder and enhancing adaptive capacity. The project scope and design process includes four major tasks: scope the project and define its objectives, establish the project team, review and synthesize existing information on vulnerability and adaptation, and design the APF project. The main purpose of assessing current vulnerability and adaptation is to understand the characteristics of current climate-related vulnerability in priority systems and the scope of adaptive responses. Future climate-related risks are assessed in order to characterize future climate-related risks, so that adaptation policies and measures can be designed to reduce the system's exposure to future climate hazard. In developing an adaptation strategy, all of the preceding APF-related work is synthesized into a well-considered strategy that can direct real adaptation action. Continuing the adaptation process is in order to implement and sustain the APF-strategy, polices, and measure. The purpose of involvement of stakeholders is to communicate between individuals and groups about projects. Finally, enhancing adaptive capacity provides guidance on how adaptive capacity can be assessed and enhanced.

중소기업을 위한 제품정보관리 시스템과 웹기반 CAE 지원 시스템의 연동 (Connection of PDM System and Web-Based CAE Supporting System for Small and Medium Enterprises)

  • 방제성;이재경;한승호;박성환;이태희
    • 한국CDE학회논문집
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    • 제13권6호
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    • pp.459-468
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    • 2008
  • A web-based Computer-Aided Engineering (CAE) supporting system is connected with a Product Data Management (PDM) system for Small and Medium Enterprises (SMEs) suffering from the lack of building hardware, software and related experts. An analysis of current business models and worksite requirements provides an improved process model and data to be shared between the PDM system and the CAE supporting system. Since all engineering tasks such as geometric modeling, mesh generation, static stress and modal analysis, and fatigue durability analysis are automated in the CAE supporting system, the user in charge of the CAE have only to configure the concerned values of design variables and result data through the web page. The existing Change Management module of the PDM system is modified for seamless data exchange, i.e. sending the Engineering Change Order (ECO) data to the CAE supporting system and receiving the CAE result data bark. The hi-directional data transfers between the PDM system and the CAE supporting system is made possible by adaptors bused on the Simple Object Access Protocol (SOAP). The current approach will be very helpful for SMEs that only have the PDM system and have no adequate infrastructure for CAE.

패션산업의 환경변화에 따른 패션 머천다이징의 새로운 패러다임 (A New Paradigm of Fashion Merchandising as an Environmental Change of the Fashion Industry)

  • 장성환
    • 한국의류학회지
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    • 제34권1호
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    • pp.175-188
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    • 2010
  • This study suggests a new paradigm of fashion merchandising as an environmental change of the fashion industry. The study has the pattern of a literature study and it is analyzed through journals, professional books, fashion magazines, and newspapers. Examined are the environmental changes of the fashion industry, the condition, and problems of the merchandising process that is executed currently, as well as an examination of the concept of fashion merchandising, Concepts and changes for new fashion merchandising strategies are suggested that are helpful for academics and fashion companies. This paper defines the concept of new fashion merchandising as the integrated management activity of planning, development, and selling fashion products to create a profit for the company with the satisfaction of the target customers. This study proposes the pursuance of integrated merchandising, the change of product planning and product development, and the strengthening of store-centered retail merchandising in order to change the direction of fashion merchandising.

Requirement Analysis and Optimal Design of an Operational Change Detection Software

  • Lee, Young-Ran;Bang, Ki-In;Shin, Dong-Seok;Jeong, Soo;Kim, Kyung-Ok
    • 대한원격탐사학회지
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    • 제20권3호
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    • pp.189-196
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    • 2004
  • This paper describes what an operational change detection tool requires and the software which was designed and developed according to the requirements. The top requirement for the application of the software to operational change detection was identified: minimization of false detections, missing detections and operational cost. In order to meet such a requirement, the software was designed with the concept that the ultimate decision and isolation of changes must be performed manually by visual interpretation and all automatic algorithms and/or visualization techniques must be defined as support functions. In addition, the modular structure of the proposed software enables the addition of a new support function with the minimum development cost and minimum change of the operational environment.

아파트조경공사 설계변경의 유형분류와 특성분석 (Classification and Analysis of Characteristics of Changes in Apartment Landscape Work)

  • 박춘수;박승범
    • 한국조경학회지
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    • 제37권1호
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    • pp.28-42
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    • 2009
  • 조경공사 중 설계변경을 통하여 이루어지는 기술적 검토사안들을 토대로 설계변경의 유형분류체계를 제시하고 유형별 발생빈도와 규모, 유형간 상관성, 현장별 차이분석을 통하여 아파트단지 조경공사 설계변경의 특성을 밝히고자 하였다. 대한주택공사 충청권지역에서 2004년부터 2006년 상반기까지의 설계변경 건을 대상으로 설계변경 시 목적 및 사유로서 언급한 사안을 중심으로 유형을 구분한 결과, 단지이미지, 경관요소, 이용자 고려, 하자방지, 시공성, 현장여건, 공종간 불일치, 상위기준, 민원방지, 설계내역, 기타의 11개 유형과 47개 세부요인으로 구분하였다. 설계변경심사승인 횟수와 시기, 유형별 발생빈도와 변경규모 증감액, 상관관계를 조사 분석한 결과, 첫째, 단지이미지형 설계변경이 발생빈도 22%, 증감액 54.9%를 차지하는 주된 설계변경이었고, 둘째, 유형간 상관성 분석에서 단지이미지형 설계변경의 증가액이 커질수록 사유가 불명확한 기타 설계변경의 감소액이 커지는 반비례관계가 성립되는 등 공사비 증가를 상쇄하는 절감노력이 이루어지고 있었으며, 셋째, 설계변경심사승인 건수와 최초심사승인일은 각각 2건 이내와 준공 전 90일 이내가 $52{\sim}53%$를 차지하여 설계변경 절차가 적기에 이루어지도록 하기 위한 제도인 설계변경심사승인 자체가 사후 일괄적으로 처리되고 있었는데, 이는 공사비가 감소한 유형수와 비교결과 공사비 절감노력 즉, 예산문제에서 기인하고 있었다.

아파트의 규모에 따른 리모델링 실태 연구 - 아파트 주호의 개조자료 분석을 중심으로 - (A Study on the Remodeling of Apartment Housing Unit according to the Size - Focusing on the Data Analysis of Apartment Housing Unit Remodeling-)

  • 신경주;이지영;장상옥
    • 한국실내디자인학회논문집
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    • 제13권6호
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    • pp.82-90
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    • 2004
  • The purpose of this study is to investigate the remodeling of apartments housing unit according to the area type and size in order to provide useful information for future plans for more consumer-friendly dwelling units. To achieve this goal quantitative data analyses were employed. The sample was a total of 100 apartments analysed in previous researches conducting case studies on apartments remodeling. The data were analyzed by SPSS WIN program package in terms of frequency, percentage, and x2-test. The results of the study are as follows: The change of finishing materials were made in almost all of the sample. 6.4, 8.6 and 10.6 categories were altered in the small, medium, and large apartments respectively out of 21 remodeling categories. In the case of communal areas, change of finishing materials and installation, removal, and change of lighting fixtures were most frequent. The most frequent alteration in private areas was also observed In change of finishing materials and installation, removal and change of lighting fixtures.

Application of Big Data and Machine-learning (ML) Technology to Mitigate Contractor's Design Risks for Engineering, Procurement, and Construction (EPC) Projects

  • Choi, Seong-Jun;Choi, So-Won;Park, Min-Ji;Lee, Eul-Bum
    • 국제학술발표논문집
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    • The 9th International Conference on Construction Engineering and Project Management
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    • pp.823-830
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    • 2022
  • The risk of project execution increases due to the enlargement and complexity of Engineering, Procurement, and Construction (EPC) plant projects. In the fourth industrial revolution era, there is an increasing need to utilize a large amount of data generated during project execution. The design is a key element for the success of the EPC plant project. Although the design cost is about 5% of the total EPC project cost, it is a critical process that affects the entire subsequent process, such as construction, installation, and operation & maintenance (O&M). This study aims to develop a system using machine-learning (ML) techniques to predict risks and support decision-making based on big data generated in an EPC project's design and construction stages. As a result, three main modules were developed: (M1) the design cost estimation module, (M2) the design error check module, and (M3) the change order forecasting module. M1 estimated design cost based on project data such as contract amount, construction period, total design cost, and man-hour (M/H). M2 and M3 are applications for predicting the severity of schedule delay and cost over-run due to design errors and change orders through unstructured text data extracted from engineering documents. A validation test was performed through a case study to verify the model applied to each module. It is expected to improve the risk response capability of EPC contractors in the design and construction stage through this study.

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Decision Making Method based on Function and Performance Matrix Assessment Considering Design Change

  • Oh, Youngsuk;Chun, Jaeyoul;Cho, Jaeho
    • Architectural research
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    • 제17권3호
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    • pp.83-91
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    • 2015
  • A comprehensive understanding of functions and performances enables a selection of appropriate alternatives to the existing design and can prevent defective design. A performance-based design quality management can ensure successful project completion. This study proposes a new model for design quality management in order to prevent defective design and to minimize design change. The new quality management model defines the requirement about function and performance based on technical characteristic, and assesses suitability for design alternatives. This study attempts to propose a quality matrix assessment method that can compare the alternative design and requirements defined with the new quality management model. This method can judge conformity and suitability of design quality in accordance with the requirements configured.

현가계의 교체가 가능한 모듈형 실험차량의 개발 (A Development of Modular Experimetal Vehicle for Exchanging Suspension Systems)

  • 배상우;강주석;윤중락;이장무;탁태오
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.847-851
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    • 1996
  • In this study, in order to adapt various types of suspensions that is not possible for a passenger car, and to validate the effect of the design change of a suspension upon ride and handling characteristics of vehicle, the modular experimental vehicle, which makes possible to exchange suspension systems, has been designed and developed. In order to enable the assemblage between the modules, the experimental vehicle design is based on a space frame construction through finite element analysis. Moreover, the module frames and the brackets are designed are designed using three- dimensionalsolid modeler to check the interference between each part of a vehicle. The results of simulation and experiment are compared.

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