• Title/Summary/Keyword: Change Order(Design Change)

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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 (High-Order QAM에 적합한 반송파 동기회로 설계 - II부. 자동모드전환시점 검출기 및 평균모드전환회로를 적용한 Gear-Shift PLL 설계 및 성능평가)

  • Kim, Ki-Yun;Kim, Sin-Jae;Choi, Hyung-Jin
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.4
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    • pp.18-26
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    • 2001
  • In this paper, we propose an ATC(Automatic Transfer mode Controller) algorithm and an average-mode-change method for use in Gear shift PLL which can automatically change loop gain. The proposed ATC algorithm accurately detects proper timing or the mode change and has a very simpler structure - than the conventional lock detector algorithm often used in QPSK. And the proposed average mode change method can obtain low errors of estimated frequency offset by averaging the loop filter output of frequency component in shift register. These algorithms are also useful in designing ASIC, since these algorithms occupy small circuit area and are adaptable for high speed digital processing. We also present phase tracking performance of proposed Gear-shift PLL, which is composed of polarity decision PD, ATC and average mode change circuit, and analyze the results by examining constellation at each mode.

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

  • Shm, Im-Chul;Lee, Eun-Jeong;Kwon, Won-Tae;Lim, Jaekyu
    • Atmosphere
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    • v.15 no.1
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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.

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

  • Bang, Je-Sung;Lee, Jai-Kyung;Han, Seung-Ho;Park, Seong-Whan;Lee, Tae-Hee
    • Korean Journal of Computational Design and Engineering
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    • v.13 no.6
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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.

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

  • Chang, Sung-Hwan
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.1
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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
    • Korean Journal of Remote Sensing
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    • v.20 no.3
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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.

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

  • Park, Chun-Soo;Park, Seung-Burm
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.1
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    • pp.28-42
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    • 2009
  • In the wake of categorizing the design changes occurred during the period from 2004 till the first half of 2006 in Choongcheong province area, based on purpose and reason of design changes identified by the Korea National Housing Corp, it included 11 types such as the image of the apartment complex, scenic elements, consideration by the user, prevention of the defect, constructability, site conditions, incompatibility between the activities, superordinate standard, prevention of civic complaints, design details and others, along with 47 subordinate elements. And the evaluation intended to identify the corelation between the number and time of design change approval, frequency and scale of design change by type and the cost variations indicated that; firstly, enhancing the image of the apartment complex proved to be the main reason for design changes, accounting for 22% in terms of frequency and 54.9% in terms of cost variation. Secondly, the higher the increase in cost by design change aimed at improving the image of the complex, the lower the decrease in cost by design change for uncertain reasons, dubbed the inverse proportional relations, indicating that the design changes for uncertain reasons were mostly aimed at reducing the construction cost. Thirdly, with regard to the number of design change approval and the time of the initial approval, twice or less and 90 days or less before completion of the construction work, respectively, accounted for $52{\sim}53%$, indicating the design change deliberation and approval tended to have been carried out collectively in the form of ex post facto approval, which seemed to be attributable to the attempt of reducing the construction cost or budget problem, as a result of comparing with the cases in which the cost was reduced.

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

  • Shin Kyung-Joo;Lee Jee-Young;Jang Sang-Ock
    • Korean Institute of Interior Design Journal
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    • v.13 no.6
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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
    • International conference on construction engineering and project management
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    • 2022.06a
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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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    • v.17 no.3
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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.

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

  • 배상우;강주석;윤중락;이장무;탁태오
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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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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