• Title/Summary/Keyword: 공기단축

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Arterio-Venous Line Connection for Effective Intracardiac Deairing after Open Heart Surgery (개심술 후 저류공기의 효과적인 제거를 위한 동정맥도관의 설치)

  • 정성운;김종원;박준호
    • Journal of Chest Surgery
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    • v.36 no.11
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    • pp.834-838
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    • 2003
  • Background: Deairing from the heart after open heart surgery(cardiopulmonary bypass) is a very important procedure. Artificial arteriovenous fistula was used to remove air, and the efficiency was evaluated by transesophageal echocardiography. Material and Method: Just before termination of cardiopulmonary bypass, a standard pressure transducer line is connected between the stopcocks of the connections in the arterial and venous circuits, creating a small controlled arteriovenous fistula between the arterial and venous cannulas. The degree of intracardiac air and air removal time were evaluated either by transesophageal echocardiography or direct vision of pressure transducer line. Result: By simple procedure, cardiopulmonary time was shortened and air clearing can be confirmed using echocardiography in a few minutes. Conclusion: Creation of arteriovenous fistula using small connecting line between aortic and venous cannula is a very simple and effective method of deairing and preventing of air embolism after open heart surgery.

정보화가 건설기업의 승패를 좌우한다

  • Kim, In-Su
    • 주택과사람들
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    • s.188
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    • pp.30-33
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    • 2006
  • 정보화가 기업의 승패를 좌우하는 화두로 등장하고 있다. 특히 건설정보화 전략은 공기 단축 · 공비절감 등 건설프로젝트 수행의 최적수단으로 작용하면서 기업경영의 기본 인프라로 자리매김하고 있다. 과거 정보화가 비용으로 인식됐다면, 현재에는 투자로 인식될 만큼 정보화 마인드가 바뀐 것도 사실이다. 건설정보화의 현주소를 추적했다.

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Feasibility Analysis of the Use of Architectural PC for Improving the Productivity in Apartment Housing Projects (공동주택 공사에서의 생산성 향상을 위한 건축 외관용 PC의 적용 타당성 분석)

  • Lee, Hyun-Seok;Sohn, Young-Jin;Lee, Yoon-Sun;Kim, Jae-Jun
    • Korean Journal of Construction Engineering and Management
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    • v.9 no.3
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    • pp.118-125
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    • 2008
  • In Korea, five days per week system, duration reduction bidding system, and post sale system have recently stimulated an interest in productivity improvement in construction project. However, analysis result of productivity in Korean construction industry found that the productivity is too low. APC (Architectural PC) is alternative of reveal wall and parapet in apartment housing prcjects and is used abroad broadly because of duration reduction for productivity improving. APC is used as external curtain wall in Dubai, North America, and Southeast Asia. Therefore, it is proposed that necessary to Introduce APC in Korea. The objective of this study is to draw up introduction of APC in apartment housing projects. We analysed the feasibility of the use of APC. The survey results reported that APC would be able to improve the productivity in the eight productivity factors.

Reducing the Test Time for Chemical Durability of PEMFC Polymer Membrane (PEMFC 고분자막의 화학적 내구성 평가시간 단축)

  • Oh, Sohyeong;Cho, Wonjin;Lim, Daehyeon;Yoo, Donggeun;Park, Kwonpil
    • Korean Chemical Engineering Research
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    • v.59 no.3
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    • pp.333-338
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    • 2021
  • The durability of the PEMFC stack for large commercial vehicles should be more than 5 times that for passenger vehicles. If the Chemical Accelerated Stress Test (AST) of PEMFC(Proton Exchange Membrane Fuel Cells) membrane for passenger cars is applied as it is for large commercial vehicles, there is a problem that the AST time becomes more than 2,500 hours. In order to shorten the AST time of DOE (Department of Energy), the chemical durability of the polymer membrane was evaluated using oxygen instead of air as a cathode gas. In this study, Nafion XL was used as a polymer membrane to evaluate accelerated durability under OCV, 90?, RH 30%, H2/(air or oxygen) conditions. Among the DOE membrane durability target criteria, the decrease rate of short resistance was the fastest. By using oxygen instead of air, the degradation rate of the polymer membrane was accelerated while being less affected by electrode deterioration, reducing the polymer membrane durability evaluation time to less than half.

A Study on the Strategy for Creating Demand of Modular Construction through Case Analysis by Building Type (건물 유형별 사례분석을 통한 모듈러 공법 수요창출 방안 수립)

  • Kim, Dong-Soo;Kim, Kyung-Rai;Cha, Hee-Sung;Shin, Dong-Woo
    • Korean Journal of Construction Engineering and Management
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    • v.14 no.5
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    • pp.164-174
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    • 2013
  • It has been seriously difficult to create demand of modular construction because Korean modular method has been considered as container house or lightweight steel house. Actually, barrier factor of modular construction for activation was difficult to produce modular continuously in factories based on stable amount of demands. So, this research found successive factors of modular construction and proposed the method of demand creation through a plethora of case analysis by building types. In addition, this research found the scale of modular potential market. Owners will be able to use this strategy that is proposed in this research when they make a decision about construction system. Also, the modular construction can make potential market in Korea. As a result, modular system producer can make their business strategies and make continuous demand by conjugating the method of creating demand for modular construction which is proposed in this research.

A Process Improvement in Building Constructions using Value Stream Analysis - Focused on slab works - (가치흐름 분석을 통한 건설공사의 공정개선방안 - 슬래브 공사를 중심으로 -)

  • Lee Hyung-Soo;Yoon You-Sang;Suh Sang-Wook;Jang Chan-Hee
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.527-530
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    • 2002
  • The purpose of this study is to present an improvement of the form work process. The current slab form work has waste factor by unnecessary process and not complete integration with the finishing process. Therefore the study used value stream analysis methodology for effective improvement of slab form work process. The main contents of the study are as follows; 1) Understanding of non-value adding activities in existing slab form work process 2) Process integration by value stream mapping 3) Effect analysis of time-cost reduction. The study recommends that, as a future research, development of tool and technique for the non-value adding activities are eliminated in building construction.

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Construction Application of a Newly Developed Form-Latticed Prefabricated Steel Reinforced Concrete Column (Form-LPSRC 기둥 개발 및 적용 연구)

  • Baek, Hojin;Lee, Seung-Hwan;Kim, Sooyoung
    • Journal of the Korea Institute of Building Construction
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    • v.14 no.5
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    • pp.487-495
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    • 2014
  • Shortening the construction duration of structural frame work is extremely important because the work accounts for a major percentage of all cost and duration in large projects. For this reason, new construction methods to reduce the duration of structural frame work are being continuously studied and developed. A PSRC composite column, which uses steel angles instead of H-beams, has the advantages of flexural strength and ductility. Moreover, with this PSRC technique, conventional work for reinforcing bars in columns in practice can be skipped. However, one limitation exists in which the form work is still required. This research proposes a Form-LPSRC column method that is prefabricated with the column frame that includes permanent forms attached. Feasibility was examined with mock-up specimens and finally, the technique applied to real practice. Compared to the conventional SRC column method, this study demonstrated that the proposed technique has many advantages in construction duration, cost, quality, safety and environment.

New Building Materials and Methods for Modernized Korean Housing (Hanok) (보급형 신한옥을 위한 부위별 공법 개발 및 영향도 분석)

  • Kim, Min;Kim, Hyosun;Ryu, Jaeseon;Jung, Youngsoo
    • Korean Journal of Construction Engineering and Management
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    • v.15 no.2
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    • pp.23-32
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    • 2014
  • Modernized Korean housing (Hanok) with competitive price has been actively developed due to the increased interests in traditional Korean housing. Developing new building materials and methods is an essential area for Modernized Hanok. This paper compared and analyzed two mock-up buildings of Modernized Hanok and one mock-up of Traditional Hanok those were actually constructed as test-beds. Many different new methods were introduced, and their influences on construction cost and schedule were analyzed in order to verify the research results as well as to find implications for future direction. As a result, the construction cost and schedule of Modernized Hanok have been decreased by about 40% and 20%, respectively, when compared with traditional one. 'Wood frame' and 'Roof' are found as being the most influencing areas with highest weights in terms of cost and schedule. Therefore, further development in these two areas would facilitate to reduce overall cost of Modernized Hanok with improved building performance.

건설공사장 소음.진동 국내현황 및 문제점

  • 조창근;김하근
    • Journal of KSNVE
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    • v.7 no.4
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    • pp.561-565
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    • 1997
  • 사회기반시설의 확충, 도시재개발 등을 위하여 대규모 건설공사가 증가하고 있으며, 공기단축과 인건비 절감 등을 위하여 건설현장에서는 대형 건설장비가 사용되고 있다. 최근 들어 주민들의 안전, 환경에 대한 의식수준이 높아지면서 이들 건설공사장에서 발생하는 소음.진동 때문에 많은 건설공사장에서는 민원해결을 위하여 상당한 비용을 지불하고 있는 실정이다. 본 고에서는 국내 건설공사장에서 발생하는 소음.진동의 합리적인 저감대책을 수립하기 위하여 국내 건설공사장의 소음.진동 발생실태와 대책사례, 문제점 등을 소개하고자 한다.

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