• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.612-614
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• 1998

As chip feature size decrease, interconnect delay gains more importance. A accurate timing analysis required to estimate interconnect delay as well as cell delay. In this paper, we present a timing-level delay calculation tool of which the accuracy is bounded within 10% of SPICE results. This delay calculation tool generates delay values in SDF(Standard Delay Format) for parasitic data extracted in SPEF(Standard Parasitic Exchange Format). The efficiency of the tool is easily seen because it uses AWE(Asymptotic Waveform Evaluation) algorithm for interconnect delay calculation, and precharacterized library and effective capacitance model for cell delay calculation.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2003년도 학술대회지
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• pp.438-441
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• 2003

건설 산업 대부분의 프로젝트에서 공기지연의 발생은 매우 일반적이나 CPM, Bar Chart와 같은 지연분석 기법들로서는 분석하기 매우 어렵다. CPM과 Bar chart를 이용하는 분석기법들은 동시발생과 생산성 손실 지연을 분석하기에 불충분하기 때문이다. 생산성 손실 지연은 동시발생 지연 분석 및 지연 일수 산정에서 중단으로 인한 지연과 다르게 분석되어야 한다. 본 논문에서는 동시발생 공기지연 분석을 포함하여 생산성을 고려한 공기지연 분석방법에 대하여 논하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.441-444
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• 2003

Network uncertainties such as data loss and time delay can vary the stability property of networked control system. Therefore, these uncertainties must be considered first in designing networked control system. In this paper, we present a new stability analysis method of networked control system with data loss and time delay. The proposed method can determine maximum allowable time delay and minimum allowable transmission rate that preserves stability performance of networked control system. The results of the simulation validate effectiveness of our stability analysis method.

• Journal of Communications and Networks
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• 제17권3호
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• pp.275-285
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• 2015

To improve the efficiency of carrier sense multiple access (CSMA)-based medium access control (MAC) protocols, CSMA with collision resolution (CSMA/CR) has been proposed. In the CSMA/CR, a transmitting station can detect a collision by employing additional sensing after the start of a data transmission and then resolve the next collision that might occur by broadcasting a jam signal during a collision detection (CD) period. In this paper, we analyze the delay of a CSMA/CR based on a generic p- persistent CSMA model and obtain the minimum achievable delay of the CSMA/CR by finding the optimal length of the CD period according to the number of contending stations. Through this delay analysis, we also investigate the throughput-delay characteristics of the CSMA/CR protocol according to various parameters. Analysis and simulation results show that the CSMA/CR has a considerably lower delay and its throughput-delay characteristic is significantly improved than the conventional CSMA/CA and wireless CSMA/CD protocols.

• Journal of Construction Engineering and Project Management
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• 제2권3호
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• pp.17-29
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• 2012

Delays are one of the biggest problems facing by the construction industry and they have significant financial and social impact in construction projects. The paper presents a framework of Delay Analysis System (DAS) with the aim of analysing the impact of delay factors in Libyan construction projects. The system has designed by integrating the possible delay factors, critical activities of a project using@risk simulator. A case study of building project was demonstrated to identify the impact of delays and the sensitivity of delay factor. The case study result showed that the project might be delayed by 97 to 103 days in comparison to the planned duration. The developed DAS is a tool for analysing and identify the impacts of delay factors and assist to construction manager to take necessary measure in reducing the delay impact. The paper provides a methodology for analysing the possible delay impact in a construction project and informing to construction manager in advance of the possible delay factors.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1474-1479
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• 2004

In this paper, the design of the network system using the CAN and the analysis of effects of time delay in the system are presented. A conventional implementation technique induces many problems because of the amount and complexity of wiring and maintenance problems. The network system reduces these problems, but it cause another problem; time delay. Time delay in a sampling time does not have much effects on the system, but time delay over the sampling time changes the control frequency and ended up makes the system unstable. It is verified that time delay between each parts has different effects on the entire system. The results from this paper will be a base for studying algorithms to reduce effects of time delay in the system using the CAN.

• 한국건설관리학회논문집
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• 제9권5호
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• pp.214-226
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• 2008

Construction delay caused considerable losses to project parties. Avoiding construction delays is important to save costs for project stakeholders. The main objective of this paper is to identify major causes of construction delays of apartment construction projects in Vietnam. Sixteen causes of delay were identified through a questionnaire survey of 166 professionals. Factor analysis was employed to categorize these causes. The results of the survey revealed the main causes of delay of apartment projects in Vietnam are: (1) owner's and contractor'S financial difficulties; (2) lack of experienced contractors; (3) late delivery of materials; (4) late construction site handover; (5) owner's late payments for completed works; (6) low bid prices; (7) inappropriate construction method; and (8) defective works and unnecessary reworks. Factor analysis uncovered that causes of delay can be grouped under five categories labeled the five INs: incompetence, ineffectiveness, inadequateness, inapplicableness and inconceivableness. Comparative analysis between the Vietnam construction industry (VCI) and the Korea construction industry (KCI) has been performed to infer valuable lessons for researchers and practitioners in the VCI and the KCI. Comparative analysis indicated that main causes of delay in the VCI somewhat differ from main causes of delay in the KCI. However, "contractor'S financial difficulties", "late construction site handover", "unnecessary rework", "incapable designers", "site clearance difficulties" are common causes of delay in the VCI as well as the KCI. The findings of this research can be used as a guideline to overcome problems in the VCI as well as in other construction industries. Since Korea has emerged as the first largest foreign investor in Vietnam, the results of this study may be useful not only to practitioners and researchers in Vietnam but also to participants in Korea.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.599-599
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• 2015

This research attempts to resolve the construction delay issues of indirect delays by developing the "Delay Responsibility Determination Model" (DRM) based on probabilistic risk analysis. DRM is envisioned to provide a way of quantitatively analyzing impacts of delayed activities while considering both direct and indirect influences. With the successful development of DRM, it would be possible to present relative probabilistic measures to all the related stakeholders in terms of their contributions to schedule delays. Upon the development completion of DRM, "Korean Construction Delay Claim/Dispute Resolution Protocols" will also be prepared to facilitate the effective use of DRM.

• 한국의류학회지
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• 제32권5호
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• pp.766-776
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• 2008

The purpose of this study was 1) to identify the reasons for delay of decision making and the shopping information in internet shopping, 2) to classify consumers based on the clothing benefits, 3) and to examine the differences among consumer groups in the reasons for delay of decision making and the shopping information. The data were collected from a sample of 500 internet shopper aged from 20 to 40. This study used factor analysis, multiple regression analysis, Pearson's correlation analysis, cluster analysis and ANOVA. The results showed that the reasons for delay of decision making consisted of eight factors: Performance risk, Comparison shopping, Economic shopping, Social risk, Uncertainty, Expecting of market change, Product unsatisfaction, Passive shopping. The shopping information consisted of three factors: Product variety, Product information, Additional information. Five factors of clothing benefits were Economy, Figure compensation, Social position, Individuality, and Comfort. The respondents were classified into four groups by five factors of clothing benefits; Individuality seeking group, Low-benefits seeking group, Economy seeking group, Figure compensation/comfort seeking group. There were significant differences among groups in the reasons for delay of decision making and the shopping information among groups. Therefore, marketers need to provide different shopping information for delay closure by target groups.

• 한국건축시공학회지
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• 제11권1호
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• pp.9-17
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• 2011

건설프로젝트에서 공기지연은 공정 및 공사비 관리 측면에서 핵심 관리사항에 해당된다. 본 연구는 아파트 건설공사에서 직접비의 상당부분을 차지하는 골조공사를 대상으로 공사부위별 공기지연 수준을 분석하고 대책을 제시한 실증연구로 10개 현장의 공사비 비중분석 결과에 기반하여 골조공사에서 지연이 발생하는 부위의 순위, 원인 등을 분석하였다. 분석결과 1층 골조공사에서 가장 큰 지연이 발생하는 것으로 나타났으며 지연원인을 다양한 분류에 의거하여 분석하고 대책을 제시하였다.