공사실적자료를 이용한 개략견적시스템의 보정계수 Database 구축 및 활용 사례

우성권(Woo Sungkwon),정영수(Jung Youngsoo) 대한토목학회 2001 대한토목학회논문집 D Vol.21 No.5D

발주자 관점의 생산적인 건설 프로젝트와 영향요소의 분석에 관한 연구

우성권(Woo, Sungkwon),이영환(Lee, Young-Hwan),장철기(Chang, Chul-Ki),이시욱(Lee, Siwook) 대한토목학회 2012 대한토목학회논문집 D Vol.32 No.6D

고속도로 건설공사의 경우 기존에 건설된 고속도로에 대한 유지관리비가 증가하고 있어 신규 건설에 필요한 투자비에 대한 효율성의 혁신 및 프로젝트의 품질을 향상시키기 위한 생산성 관리가 필요한 시점이지만, 아직까지 고속도로 건설공사에 대한 생산성 및 성과 측정에 대한 명확한 기준이나 방법, 필요성이 제대로 정립되지 못하고 있는 실정이다. 이에 본 연구는 발주자의 주요 업무인 사업관리 측면에서 생산적 프로젝트의 5가지 주요 구성 요소를 정의하였다. 그리고 생산성에 주요한 영향을 미치는 43개 생산성 영향요소를 정의하고 이들을 세 개의 레벨로 구성된 위계체계로 정의하였다. 또한 고속도로 건설공사의 최대 발주자인 한국도로공사를 대상으로 설문조사를 수행하여 정의된 생산성 영향요소들이 생산적 프로젝트의 달성에 미치는 영향 정도를 파악하고 개선수요 정도를 파악함으로써, 사업의 성공적인 수행을 위하여 중점적으로 관리하여야 할 영향요소를 제시하였다. The productivity management of highway construction is required to innovate the efficiency of investment The productivity management of highway construction is required to innovate the efficiency of investment cost for newly constructed projects and to improve the quality of these projects, as the maintenance and management expenses are steadily increasing for existing highways under operation. However, clear criteria, methods or requirements to measure the productivity and performance in the construction of highways have not been properly established yet. This study defined 5 major elements of the productive projects in terms of construction management which is one of major tasks of the owner. There were the 43 influential elements significantly affecting on the productivity and these elements were categorized into the hierarchical structure which was composed of 3 levels. Also, this study conducted a survey for Korea Expressway Corporation who is the largest owner in Korea’s highway construction. As a result, major project performance indicators, which should be addressed for management, to execute the projects successfully, are presented through understanding the extent of the affection of productivity elements on the elements of project performance to attain the productive projects and through understanding the extent of demand to be improved.

건설공사 예정가격의 하도급자 간접비 계상에 대한 연구

한상준(Han, Sang Jun),이시욱(Lee, Siwook),우성권(Woo, Sungkwon),이승우(Lee, Seung Woo),김종우(Kim, Jong Woo) 대한토목학회 2023 대한토목학회 학술대회 Vol.2023 No.10

변형 리키 LMS 알고리즘을 이용한 DS-CDMA 시스템의 채널 추정

조성권(Sungkwon Jo),최지훈(Jihoon Choi),우연식(Yeon Sik Woo),서주원(Ju Won Soh),이용훈(Yong Hoon Lee) 한국통신학회 2001 한국통신학회 학술대회 및 강연회 Vol.2001 No.4

선박엔진의 SCR 성능 향상 및 촉매재생을 위한 플라즈마 버너 실증 평가

조성권(Sungkwon Jo),조동현(Donghyun Cho),이대훈(Dae Hoon Lee),김관태(Kwan-Tae Kim),이재옥(Jae-Ok Lee),송영훈(Young-Hoon Song),장재환(Jae Hwan Jang),노희환(Hui Hwan Roh),박건면(Geon-Myeon Bak),이태우(Tae-Woo Lee),한현식(Hyun-Sik Han) 대한기계학회 2018 大韓機械學會論文集B Vol.42 No.4

선박엔진 배기가스의 국제적인 규제가 강화되고 있으며, 규제를 적극적으로 대응하기 위한 기술이 필요하다. 본 연구에서는 플라즈마 버너를 적용하여 선박엔진 배기가스의 질소산화물 저감 성능을 향상시키고, 촉매 재생에 활용하기 위한 가능성을 확인하기 위한 연구를 수행하였다. 실험을 통해, 플라즈마 버너의 연소 성능을 확인할 수 있었으며, 공연비 대비 40% 이하의 공기 조건에서의 안정적인 연소와 배기가스의 산소를 활용한 연료의 완전 연소를 확인하였다. 또한, 요소수를 환원제로 활용한 탈질실험을 수행하였으며, 플라즈마 버너를 통해 탈질 촉매의 작동 영역으로 온도를 제어하여 탈질 성능을 향상시킬 수 있음을 확인하였다. 또한, 촉매 재생을 통해 촉매의 성능이 회복되는 결과로부터 플라즈마 버너를 활용하여 탈질 설비의 내구성 향상에 기여할 수 있음을 확인하였다. We investigated the possibility of applying a plasma burner to improve NOx-reduced performance of a marine engine and to utilize it for catalyst regeneration. Through experiments, we confirmed that stable combustion can be obtained under an air condition of less than 40% air-fuel ratio and can achieve complete combustion of the fuel using oxygen in the exhaust gas. A deNOx experiment using urea as a reducing agent was performed. We confirmed that deNOx performance can be improved by increasing the temperature of the SCR with a plasma burner. Moreover, we confirmed that the performance of the SCR was restored through the regeneration process, implying that the use of the plasma burner can contribute to a durability improvement of the deNOx system in a marine engine.

콘크리트구조물 균열측정을 위한 영상획득거리 영향분석

조현우(Hyun-Woo Cho),윤혁진(Hyuk-Jin Yoon),윤재찬(Jae Chan Yoon),안성권(Sungkwon Ahn),김현기(Hyun-Ki Kim),신민호(Min-Ho Shin) 한국철도학회 2014 한국철도학회 학술발표대회논문집 Vol.2014 No.10

철도차량의 하중을 지지하는 콘크리트 구조물들은 과도한 하중에 의해 1차적으로 균열이 발생하며 균열이 성장하여 붕괴로 이어진다. 따라서, 균열을 초기에 감지하기 위하여 영상 감지 알고리즘에 관한 연구가 진행되고 있다. 기존 연구들은 실제 균열이나 하중을 가해 균열을 발생시킨 콘크리트 시편을 사용하여 균열 감지 알고리즘을 검증하였다. 이러한 균열 영상은 실제 균열과 유사한 특징이 있으나 균열 감지 성능을 정량적으로 평가하기는 부족하다는 한계가 있다. 본 연구에서는 거푸집에 두께가 다른 균열 유도판을 고정하고 콘크리트를 타설하여 균열을 정형화한 시편을 제작하였다. 제작된 시편을 이용하여 영상획득 거리를 변화시켜가면서 영상 감지 알고리즘에 미치는 영향을 분석하였다. Overload by supporting trains firstly makes the cracks on the concrete structure and the growth of cracks makes the structure collapse. Therefore, numerous researches with image process have been developed for detecting cracks early. The previous studies used real concrete crack image or generated crack by artificial load for verification of algorithm. However, these methods are difficult to evaluate algorithm performance quantitatively. In this paper, we made the crack specimen with quantitative crack width using the crack inducing plate with difference width. Using this specimen, the effect on image-based crack recognition according to image acquisition distance was analyzed.

Risk Importance and Allocation in the Pakistan Construction Industry

Asif Hameed,Sungkwon Woo 대한토목학회 2007 KSCE journal of civil engineering Vol.11 No.2

This paper on the basis of a questionnaire survey has investigated the perception of the contractors regarding risk importance and risk allocation. The purpose was to provide insight into the current attitude of Pakistani contractors towards the impact of different risks to the project delay and risk allocation. The respondents were asked to judge the relative importance of 31 risks types included in questionnaire. The risk types were generated on: a) an extensive literature review and b) consultation with the five key local experts participated in the survey. The weighted average score approach (WAS) is used to rank the potential risks based on the judgment of the respondents. The risks ranked by the contractors are analyzed and discussed. For risk allocation, the respondents have selected the party actually taking the risk from one of the following three options: owner, contractor or shared by both the owner and contractor. The results of this part of the survey are summarized in terms of percentages of the total number of respondents who have chosen the appropriate selection.

Determination of optimal accelerometer locations using modal sensitivity for identifying a structure

Kwon, Soon-Jung,Woo, Sungkwon,Shin, Soobong Techno-Press 2008 Smart Structures and Systems, An International Jou Vol.4 No.5

A new algorithm is proposed to determine optimal accelerometer locations (OAL) when a structure is identified by frequency domain system identification (SI) method. As a result, a guideline is presented for selecting OAL which can reflect modal response of a structure properly. The guideline is to provide a minimum number of necessary accelerometers with the variation in the number of measurable target modes. To determine OAL for SI applications effectively, the modal sensitivity effective independence distribution vector (MS-EIDV) is developed with the likelihood function of measurements. By maximizing the likelihood of the occurrence of the measurements relative to the predictions, Fisher Information Matrix (FIM) is derived as a function of mode shape sensitivity. This paper also proposes a statistical approach in determining the structural parameters with a presumed parameter error which reflects the epistemic paradox between the determination of OAL and the application of a SI scheme. Numerical simulations have been carried out to examine the proposed OAL algorithm. A two-span multi-girder bridge and a two-span truss bridge were used for the simulation studies. To overcome a rank deficiency frequently occurred in inverting a FIM, the singular value decomposition scheme has been applied.

CF₄ 제거를 위한 유동층 반응기를 이용한 열 플라즈마-촉매 스크러버 특성 연구

조동현(Donghyun Cho),조성권(Sungkwon Jo),강홍재(Hongjae Kang),강우석(Woo Seok Kang) 대한기계학회 2022 大韓機械學會論文集B Vol.46 No.1

지구온난화에 따른 기후 문제가 심각해지는 반면, 세계적인 반도체 수요 증가로, 온실가스인 과불화화합물 사용량이 증가하고 있다. 특히, 높은 열분해 온도를 갖는 CF₄ 제거를 위해 많은 에너지를 소모하고 있다. 에너지 효율이 높은 스크러버 기술 개발을 위해 열 플라즈마-촉매 조합에 대한 연구를 수행하였으며, CF₄ 제거 특성 및 에너지 효율을 분석하였다. 플라즈마 열의 집중에 따른 부작용을 최소화하기 위해 유동층 촉매 반응기를 적용한 새로운 열 플라즈마-촉매 반응기를 적용하였으며, 고정층 촉매반응기와의 CF₄ 분해 성능 및 온도 분포를 비교하였다. 그 결과, 높은 온도 균일성 및 95%의 CF₄ 분해율을 확인하였다. 또한, 기존 플라즈마 단독 스크러버 대비 약 2.5배 이상 에너지 효율을 확보할 수 있었다. 본 연구의 결과는 열 플라즈마-촉매 방식의 고효율 스크러버 개발에 기여할 것 기대한다. To develop a scrubber technology with high energy efficiency, a study was conducted on a thermal plasma-catalysis combination in which carbon tetrafluoride (CF₄) removal characteristics and energy efficiency were analyzed. To minimize the side effects caused by the concentration of the plasma heat, a new thermal plasma-catalysis reactor equipped with a fluidized bed was applied. The CF₄ decomposition and temperature distribution were compared with that of a fixed bed. As a result, high uniformity of temperatures and CF₄ decomposition of 95% were confirmed. In addition, it was possible to secure about 2.5 times or greater energy efficiency compared to the existing scrubber containing only plasma. The results of this study are expected to contribute to the development of an energy-efficient scrubber using a thermal plasma-catalysis.

A Novel In Vitro Ischemia/reperfusion Injury Model

Won Hee Lee,Yong Woo Lee,Sungkwon Kang,Pavlos P. Vlachos 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.3

The reperfusion of blood flow occurred in a number of conditions such as stroke and organ transplantation immensely augments tissue injury and causes more severe damage than prolonged ischemia. In the present study, we designed a novel double-layer parallel-plate flow chamber (PPFC) to develop an in vitro ischemia/reperfusion (I/R) injury model and examined the effects of I/R on inflammatory responses in human microvascular endothelial cells (HMEC-1). The expression of pro-inflammatory mediators, such as interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1), E-selectin, and vascular cell adhesion molecule-1 (VCAM-1) in HMEC-1 was measured by quantitative real-time RT-PCR. The cells were also pre-treated with antioxidant pyrrolidine dithiocarbamate (PDTC) to verify involvement of an oxidative mechanism in I/R injury in vitro. The morphological changes and attenuated expression of pro-inflammatory mediators were observed in HMCE-1 exposed to the physiological flow. In contrast, I/R markedly and significantly up-regulated expression of pro-inflammatory mediators in HMEC-1. Additionally, pretreatment with PDTC significantly reduced I/R-mediated overexpression of pro-inflammatory mediators. The data from the present study provide evidence demonstrating that our newly designed PPFC can be utilized as an effective in vitro cell culture model system to develop new drugs specifically targeting against ischemia/reperfusion (I/R) injury.