• Title/Summary/Keyword: 공기 공동

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Suggestion of Procurement Strategy with Commodity Classification by Peter Kraljic Matrix (피터 크랄직 매트릭스 기법에 의한 자재 분류를 활용한 구매 전략 제안)

  • Choi, Hyun Koo;Lee, Jae-Heon
    • Plant Journal
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    • v.11 no.3
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    • pp.53-63
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    • 2015
  • 구매자는 일반 제조업에서 자재를 피터 크랄직 매트릭스 기법에 의해 경쟁품목, 일반품목, 전략품목, 위험품목으로 분류한 후 각 품목 특성에 맞추어 구매 전략을 수립한다. 피터 클라직 매트릭스란 구매 리스크와 비즈니스 영향도 즉 특정 품목의 구매 금액 비중에 따라 자재를 분류하는 기법이다. 본 논문은 플랜트 엔지니어링산업에서 플랜트 기자재를 대상으로 피터 클라직 매트릭스 기법에 의해 기자재를 분류한 후 각 품목 특성에 맞는 구매 전략을 제안하고 사례 기업인 A사가 사우디아라비아에서 수행하는 발전 플랜트 기자재에 제안한 구매 전략을 적용하여 그 효과를 검증한 것이다. 플랜트 엔지니어링산업은 수주산업인데 총 수주금액 중 구매가 차지하는 비중은 약 50~60%이다. 따라서 프로젝트를 수행할 때 원가를 절감하여 이익을 극대화하기 위해 구매는 매우 중요한 역할을 한다. 플랜트 기자재는 크게 회전기계류, 고정장치류, 전기자재류, 제어자재류, 배관자재류로 구분된다. 각 공종별 플랜트 기자재에 대해 구매 지출 분석을 한 후 피터 클라직 매트릭스 기법에 의해 플랜트 기자재를 분류한 결과 경쟁품목에는 열교환기, 저장탱크 등이 포함되었고 일반품목에는 전선관, 조명기자재, 밸브 등이 포함되었다. 또한 전략품목에는 가스터빈, 가스터빈 흡입공기 냉각장치 등이 포함되었고, 위험품목에는 가스터빈 고정 볼트 등이 포함되었다. 경쟁품목 중 다관형 열교환기는 공급자와 공동으로 원가 모델을 구축하는 전략을 수립했고 저장탱크의 경우에는 공급자에게 원자재를 사급하는 전략을 수립하였다. 그 전략을 A사가 수행하는 프로젝트에 적용한 결과 각각 20%와 6%의 원가 절감 효과를 얻었다. 일반품목 중 전선관은 구매 대행사를 활용하는 전략을 수립했고 조명기자재는 기술 사양 검토 과정을 생략한 구매 프로세스 간소화 전략을 수립하였다. 그 결과 약 10%의 원가 절감과 평균 5일의 발주기간을 단축할 수 있었다. 전략품목 중 가스터빈 흡입공기 냉각장치는 공급자와 포괄적 양해각서를 체결하여 공동으로 사업주에 대응하는 전략을 수립했고 그 결과 프로젝트 수행 안정성 확보와 공급자 조기 참여를 통한 발주 스케줄 단축을 이룰 수 있었다. 위험품목 중 가스터빈 고정볼트는 재고 확보 전략을 수립하여 자재의 부족이나 파손으로 인해 프로젝트 공기에 영향을 주지 않도록 리스크를 감소시키는 효과를 얻었다.

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Analysis of aerodynamic characteristics for the selection of cross-section to the TBM railway tunnels (TBM 철도터널 단면선정을 위한 공기역학적 특성 분석)

  • Lee, Ho-Keun;Kang, Hyun-Wook;Kim, Hyun-Soo;Kim, Hong-Moon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.15 no.6
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    • pp.625-635
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    • 2013
  • Although the TBM method is mainly adopted in overseas market including the Europe, etc, the method scarcely adopted in domestic market. For highly enhancing applications of the TBM method for railway, It is needed to select the optimal cross-section considering design elements of civil engineering and aerodynamic effects. Also, it is needed to establish plan of proper section as well as reviewing aerodynamic effects and consideration about civil engineering elements such as length of tunnel, speed of railway, height of whole lines and size of utility tunnel, etc. Even though it should be recently considered high-speed railway tunnels and required to be standard establishments in aerodynamic reviews, it is being applied to be criteria of inconsistent pneumatic analysis owing to be not related with domestic standards. In this study, therefore, we are willing to establishment of domestic and foreign aerodynamic standards and investigate correlation between optimal cross-section and aerodynamic effects of TBM railway tunnels.

A Study on Estimating Normal Project Duration of Apartment Remodeling Project (공동주택 리모델링공사 표준공기 설정에 관한 연구)

  • Yoon, Jongsik;Yu, Ilhan
    • Korean Journal of Construction Engineering and Management
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    • v.18 no.2
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    • pp.12-20
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    • 2017
  • The biggest reason to prefer the remodeling is a relatively short period of time (5~6 years) compared to the reconstruction work that takes 8~9 years. In addition, from the perspective that the period of temporary residence is usually 24 months, the necessity of shortening is greater. Also, since the remodeling construction period is approximately 28~35 months on average, the strategies and efforts are needed to make up for the shortening the remodeling construction period. For these reasons, this paper is to develop an estimating model for normal project duration of apartment remodeling project. This model is reflected in the remodeling properties thorugh difference analysis of the new apartment construction project. Demolition works, reinforcement works, extension works are different, so this paper newly defines these construction work's duration in normal project duraion of remodeling. Case study and experts interviews are used to validate normal project duration. This model can be used to calculate rough construction period each alternatives, and will help a strategic decision making among the stakeholders.

Implementation and Design of the Framework for Consolidated Transportation Model (공동 수배송 모델을 위한 프레임워크 설계 및 구축)

  • Lee, Myeong-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.4
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    • pp.980-985
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    • 2008
  • The environment of IT is, currently, on its developing process to the period of web 2.0 and mashup which not only enable computer and internet to be utilized like the water or the air, but also be a new motivating force for its advance. One of the biggest changes of the industry that lies ahead is consolidated transportation. However, no party outstands as the leading party for nationwide improvement of logistics, nor does the right analysis and design for it. Therefore, successful nationwide logistics model is yet to exist. This study provides individual parties, which consider consolidated transportation model as their implementation and design of the framework, with instructions for logistics information system so that they could be competitive in the market. It also helps companies collect user requirements for logistics information system consolidated transportation, and utilize it for its development. Finally, the study provides a implementation and design of pilot system for consolidated transportation model.

A Study on the Progress Measurement Method using Percent Complete of Work and Labor Productivity - Focusing on Structural Works of Apartment Construction - (단위작업 물량 달성율과 투입 노무량을 이용한 진도율 산정방법에 관한 연구 - 공동주택공사의 골조공사를 중심으로 -)

  • Choi Hyun-Ha;Lee Junbok
    • Korean Journal of Construction Engineering and Management
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    • v.6 no.1 s.23
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    • pp.212-219
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    • 2005
  • Time management is important in construction management Especially, in the high-rise apartment housing projects, it is very important to expedite the construction progress in order to meet the planned schedule. The objective of this paper is to propose the baseline for the progress rate using work volume and man $\cdot$ hours performed at work activity level. The work volume far each activity is transformed to the weighted value compared to total work volume for the floor Therefore, a progress rate for an activity is calculated by multiplying a weighted value and work volume. A progress rate for a floor and a building can calculated in this manner, respectively.

Performance Evaluation of Multidrop Chamber Ventilation System in Apartment (공동주택내 다분기챔버형 환기시스템 적용을 통한 풍량분배 개선효과에 관한 연구)

  • Kim, Sung-Soo;Son, Jang-Yeul
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.21 no.10
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    • pp.545-552
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    • 2009
  • It is common to design the duct branches where to supply the required air flow for individual room in residential apartment house. And TAB process is applied to control the designed air volume with adjusting volume dampers and/or supply diffusers after fully installing the ventilation system. This process has been resulted increasing the initial cost for the residential ventilation system because of man-hour and accessories such as volume control damper or diffuser. However it is difficult to adjust the air volume adequately in small air duct branches in residential ventilation system. The purpose of this study is to figure out the performance of Multidrop chamber coupling system for the residential ventilation system.

Elevator Noise Control in Apartment Housings (공동주택의 엘리베이터 소음저감대책)

  • 김석홍;최석주;김종훈
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1995.10a
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    • pp.95-98
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    • 1995
  • 공동주택의 침실, 거실 등은 가족의 휴식처로서 매우 정숙한 환경을 필요로 한다. 최근에 많이 건설되고 있는 고층아파트에는 고속엘리베이터가 설치되고 공간절약 및 구조적 기능 등으로 인하여 엘리베이터통로가 침실이나 거실에 인접한 설계가 많이 채택되고 있다. 이러한 고층아파트의 엘리베이터 기계실 인접 세대에서는 엘리베이터 가동에 의한 공기전달음 및 고체전달음이 문제가 될 수 있으며 특히 암소음이 매우 적은 야간의 엘리베이터 소음은 수면방해 및 집중력저하를 일으켜 입주자들의 불만이 야기될 수 있다. 본 연구에서는 입주완료후 엘리베이터 소음이 문제가 된 아파트에서 소음발생원인을 측정분석하고 주로 문제가 되는 고체전달음을 저감시키기 위한 엘리베이터 방진대책을 실시하여 그 성능을 확인하고 이 대책안을 문제가 되는 기존아파트나 추후 건설될 아파트의 엘리베이터 소음저감대책으로 제시하고자 한다.

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The Air-stripping Process Conjugated with the Ultrasonic Treatment to Remove TOC in Groundwater around the LPG Underground Storage Cavern (탈기법과 초음파 처리법을 연계한 LPG 지하공동저장소 주변 오염지하수 내 TOC 제거)

  • Han, Yikyeong;Jun, Seongchun;Kim, Danu;Jeon, Soyoung;Lee, Minhee
    • Economic and Environmental Geology
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    • v.55 no.5
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    • pp.511-519
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    • 2022
  • In order to develop an air-stripping based remediation process to remove the TOC (Total Organic Carbon) in groundwater around the underground LPG storage cavern, the laboratory scale experiments at various conditions (change of air injection volume and temperature, the application of ultrasonic treatment, etc.) for two types of groundwater (initial TOC concentration of 608 mg/L and 153 mg/L, respectively). From results of experiment, as the air injection rate for stripping into groundwater increased from 2 L/min to 11 L/min and as the air-stripping time increased from 1 hour to 24 hour, the TOC removal efficiency of air-stripping increased. However, the TOC concentration of treated groundwater was higher than the discharge tolerance limit (100 mg/L) even after 24 hour stripping at the maximum air injection rate of 11 L/min. The main compounds of the TOC in groundwater were identified as methanol and propane and the long stripping time (more than 24 hour) was needed to separate the methanol from groundwater because of the affinity between water and methanol. At 20℃ and 4 L/min of air injection, the TOC removal efficiency increased to 59.1% after 24 hour air-stripping. When the temperature of groundwater increased to 30℃ and 40℃, the TOC removal efficiency increased up to 80.0% and 82.8%, suggesting that more than 24 hour air-stripping at 40℃ is needed to lower the TOC concentration to below 100 mg/L and the additional TOC removal process as well as the air-stripping is necessary. When the temperature increased to 60℃ and the ultrasonic treatment was conjugated with the air-stripping, the TOC removal efficiency increased to 87.8% within 5 hour stripping and the final TOC concentration (72.4 mg/L) was satisfied with the TOC discharge tolerance limit. The TOC removal efficiency for groundwater having low TOC concentration (153 mg/L) also showed similar removal efficiency of 89.7% (the final TOC concentration: 18.9 mg/L). Results in this study supported that the air-stripping conjugated with the ultrasonic treatment could remove successfully the TOC in groundwater around the underground LPG strorage cavern.

A Case Study on Reason Analysis for Schedule Delay of Apartment House (공동주택의 공기지연 원인분석 사레 연구)

  • Park, Chang-Wook;Yun, Seok-Heon
    • Journal of the Korea Institute of Building Construction
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    • v.9 no.1
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    • pp.89-94
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    • 2009
  • A study was performed the analysis for the schedule delay of the public housing. To perform this study, the first study existing research literature on the cause of the schedule delay was considered. The based on existing study, this study selected the cause of schedule delay. For check of the schedule delay, this study was compared the monthly schedule and the work diary. Survey was conducted for using the selected cause of schedule delay. And the importance was calculated for using the AHP method. In a case site, the cause of the schedule delay was analyzed. The last, the delay cause was presented the map of cause of effect the based on the delay cause of a case site.

Evaluation of Field Application on the Prediction Method of Early-age Strength of Early Concrete for Construction Work Period Reduction (공기단축 조강콘크리트의 조기강도 예측기술의 현장적용성 평가)

  • Lee, Woong-Jong;Keum, Kyoung-Hun;Lee, Jae-Hyun;Jung, Yang-Hee;Kim, Yong-Ro
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.443-444
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    • 2010
  • In this study, It is confirmed the validity for determination of the form removal time, utilizing prediction expression for early-stage strength which depended on the variation of curing history for early strength concrete which be passible to construction work period reduction, in apartment.

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