• Title/Summary/Keyword: co-cycle

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A Case Study of BIM-based Framework on Constructability Tasks (BIM기반 골조공사의 시공성분석 업무 적용사례에 관한 연구)

  • Lee, Seung-Il;Kwon, Nam-Ha;Cho, Young-Sang
    • Journal of the Korea Institute of Building Construction
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    • v.10 no.5
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    • pp.45-54
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    • 2010
  • Recently more and more construction projects have become high-rise, complex and intelligent. Accordingly, such projects require an integrated management system for tasks, with a lean approach to construction with work processes for management and productivity. In particular, Construction Information Technology (CIT) fields are concerned with Building Information Modeling (BIM), which represents the process of generating and managing building data during its life cycle. Constructability research has progressed for the project goal which is a cost-time-quality of optimization by integrated construction knowledge and experience. However, the current constructability process has not been performed efficiently, as the existing 2D drawings and papers lack consistent and accurate information, it is difficult to share the contents of work, and the use of information is inefficient. This study proposes that the reformation and enhancement of BIM-based constructability work process can lead to brilliant performance in the framework of the construction phase through achieving collaboration between the design team and the workers at the site.

Study on the Development of Process and Data Models for the Maintenance of Rental Apartments (임대아파트 유지관리 시스템 개발을 위한 프로세스 및 데이터 모델 구축에 관한 연구)

  • Jung, Young-Han;Jung, Jae-Young;Lee, Jae-Sung;Cho, Bong-Ho
    • Journal of the Korea Institute of Building Construction
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    • v.10 no.5
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    • pp.55-67
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    • 2010
  • The main purpose of this study is to develop a system and data model extracted from the TO-BE process model of rental apartments to promote information exchange based on knowledge obtained through maintenance status analysis. Currently, it is difficult to find examples suggesting a data model through a process analysis of maintenance in rental apartments. Thus, this study intends to suggest a process as well as a data model to promote the development of a maintenance system for rental apartments by using building management knowledge, utilization of standardized tools, and existing FM (Facility Management) techniques to break through limitations in actual application. Ultimately, this study aims to show examples of document-oriented analysis and information technology for middle managers in charge of the maintenance of rental apartments, as well as work analysts developing the maintenance system. In further research beyond this study, complex issues on the maintenance of rental apartments, legal restrictions on customary practices of maintenance activities, effects of the scales of maintenance practices, requirements to perform maintenance activities, evaluation on the status of maintenance, life cycle cost and risks will be investigated.

A Study on Characteristics of an Integrated Urea-SCR Catalytic Filter System for Simultaneous Reduction of Soot and NOX Emissions in ECU Common-rail Diesel Engines (ECU 커먼레일 디젤기관에 있어서 매연 및 NOX 배출물 동시 저감용 일체형 요소-SCR 촉매필터 시스템의 특성에 관한 연구)

  • Bae, Myung-Whan
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.4
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    • pp.111-120
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    • 2014
  • The aim of this study is to develop an integrated urea-SCR catalytic filter system for reducing soot and $NO_X$ emissions simultaneously in diesel engines. In this study, the characteristics of exhaust emissions relative to reactive activation temperature under four kinds of engine loads are experimentally investigated by using a four-cycle, four-cylinder, direct injection type, water-cooled turbo intercooler ECU common-rail diesel engine with the integrated urea-SCR $MnO_2-V_2O_5-WO_3/TiO_2/SiC$ catalytic filter system operating at three kinds of engine speeds. The urea-SCR reactor is used to reduce $NO_X$ emissions, and the catalytic filter system is used to reduce soot emissions. The reactive activation temperature is very important for reacting a reducing agent with exhaust emissions. The reactive activation temperatures in this experiment is applied to 523, 573 and 623 K. The fuel is sprayed by the pilot and main injections at the variable injection timing between BTDC $15^{\circ}$ and ATDC $1^{\circ}$ according to experimental conditions. It is found that the $NO_X$ conversion rate is the highest as 83.9% at the reactive activation temperature of 523 K in all experimental conditions of engine speed and load, and the soot emissions shown by the average reduction rate of approximately 93.3% are almost decreased below 0.6% in all experimental conditions regardless of reactive activation temperatures. Also, the THC and CO emissions by oxidation reaction of Mn, V and Ti are shown in the average reduction rates of 70.3% and 38% regardless of all experimental conditions.

Genistein-induced Growth Inhibition was Associated with Inhibition of Cyclooxygenase-2 and Telomerase Activity in Human Cancer Cells. (인체 암세포에서 genistein에 의한 cyclooxygenase-2 및 telomerase의 활성 저하)

  • Kim, Jung-Im;Kim, Seong-Yun;Seo, Min-Jeong;Lim, Hak-Seob;Lee, Young-Choon;Joo, Woo-Hong;Choi, Byung-Tae;Jeong, Yong-Kee;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.18 no.6
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    • pp.884-890
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    • 2008
  • Genistein, an isoflavone in soybean products, is a potential chemopreventive agent against various types of cancer. There are several studies documenting molecular alterations leading to cell cycle arrest at G2/M phase and induction of apoptosis; however, its mechanism of action and its molecular targets on the prostaglandin $E_2$ ($PGE_2$) production and telomere length regulation in human cancer remain unclear. In this study, we investigated the effect of genistein on the levels of cyclooxygenases (COXs) and telomere regulatory components of several human cancer cell lines (T24, human bladder carcinoma cells; U937, human leukemic cells; AGS, human stomach adenocarcinoma cells and SK-MEL-2, human skin melanoma cells). Genistein treatment resulted in the inhibition of cancer cell proliferation in a concentration-dependent manner. It was found that genistein treatment markedly decreased the levels of COX-2 mRNA and protein expression without significant changes in the expression of COX-1, which was correlated with a decrease in $PGE_2$ synthesis. Genistein treatment also partly inhibited the levels of human telomerase reverse transcriptase (hTERT) as well as human telomerase RNA (hTR) and telomerase-associated protein (TEP)-1, and the activity of telomerase. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of genistein.

Design Enhancement of CANDU S/F Storage Basket (CANDU 사용후핵연료 저장바스켓 설계 개선안 도출)

  • Choi, Woo-Seok;Seo, Ki-Seog;Park, Wan-Gyu
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.10 no.2
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    • pp.105-115
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    • 2012
  • Necessity of demonstration test to evaluate the structural integrity of a basket for accident conditions arose during license approval procedure for the WSPP's dry storage facility named MACSTOR/KN-400. A drop test facility for demonstration was constructed in KAERI site and demonstration tests for basket drop were conducted. As the upper welding region of a loaded basket was collided with a dropped basket during the drop test, the welding in this region was fractured and leakage happened after the drop test. The enhancement of basket design was needed since the existing basket design was not able to satisfy the performance requirement. The directions for design modification were determined and six enhanced designs were derived based on these directions. Structural analyses and specimen tests for each enhanced design were conducted. By evaluating structural analysis results and test results, one among six enhanced designs was decided as a final design for revision. The final design was the one to reduce the height of central post of a basket and to decrease the impact velocity with a dropped basket. Test basket models were fabricated with accordance with the final enhanced design. Additional demonstration test was performed for this test model and all the performance requirements were satisfied.

Numerical simulation of groundwater flow in LILW Repository site:II. Input parameters for Safety Assessment (중.저준위 방사성폐기물 처분 부지의 지하수 유동에 대한 수치 모사: 2. 처분 안전성 평가 인자)

  • Park, Kyung-Woo;Ji, Sung-Hoon;Koh, Yong-Kwon;Kim, Geon-Young;Kim, Jin-Kook
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.6 no.4
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    • pp.283-296
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    • 2008
  • The numerical simulations for groundwater flow were carried out to support the input parameters for safety assessment in LILW repository site. As the input parameters for safety assessment, the groundwater flux into the underground facilities during construction, flow rate through the disposal silo after closure of disposal silo and flow pathway from the disposal silo to discharge area were analyzed using the 10 cases groundwater flow simulations. From the total 10 numerical simulation results, the statistics of estimated output were similar to among 10 cases. In some cases, the analyzed input parameters were strongly governed by locally existed high permeable fracture zone at radioactive waste disposed depth. Indeed, numerical simulation for well scenario as a human intrusion scenario was carried out using the hydraulically severe case model. Using the results of well scenario, the input parameters for safety assessment were also obtained through the numerical simulation.

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Hydrogeological characteristics of the LILW disposal site (처분부지의 수리지질 특성)

  • Kim, Kyung-Su;Kim, Chun-Soo;Bae, Dae-Seok;Ji, Sung-Hoon;Yoon, Si-Tae
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.6 no.4
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    • pp.245-255
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    • 2008
  • Korea Hydro and Nuclear Power Company(KHNP) conducted site investigations for a low and intermediate-level nuclear waste repository in the Gyeong Ju site. The site characterization work constitutes a description of the site, its regional setting and the current state of the geosphere and biosphere. The main objectives of hydogeological investigation aimed to understand the hydrogeological setting and conditions of the site, and to provide the input parameters for safety evaluation. The hydogeological characterization of the site was performed from the results of surface based investigations, i.e geological mapping and analysis, drilling works and hydraulic testing, and geophysical survey and interpretation. The hydro-structural model based on the hydrogeological characterization consists of one-Hydraulic Soil Domain, three-Hydraulic Rock Domains and five-Hydraulic Conductor Domains. The hydrogeological framework and the hydraulic values provided for each hydraulic unit over a relevant scale were used as the baseline for the conceptualization and interpretation of flow modeling. The current hydrogeological characteristics based on the surface based investigation include some uncertainties resulted from the basic assumption of investigation methods and field data. Therefore, the reassessment of hydrostructure model and hydraulic properties based on the field data obtained during the construction is necessitated for a final hydrogeological characterization.

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Numerical simulation of groundwater flow in LILW Repository site:I. Groundwater flow modeling (중.저준위 방사성폐기물 처분 부지의 지하수 유동에 대한 수치 모사: 1. 지하수 유동 모델링)

  • Park, Kyung-Woo;Ji, Sung-Hoon;Kim, Chun-Soo;Kim, Kyung-Su;Kim, Ji-Yeon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.6 no.4
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    • pp.265-282
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    • 2008
  • Based on the site characterization works in a low and intermediate level waste(LILW) repository site, the numerical simulations for groundwater flow were carried out in order to understand the groundwater flow system of repository site. To accomplish the groundwater flow modeling in the repository site, the discrete fracture network(DFN) model was constructed using the characteristics of fracture zones and background fractures. At result, the total 10 different hydraulic conductivity(K) fields were obtained from DFN model stochastically and K distributions of constructed mesh were inputted into the 10 cases of groundwater flow simulations in FEFLOW. From the total 10 numerical simulation results, the simulated groundwater levels were strongly governed by topography and the groundwater fluxes were governed by locally existed high permeable fracture zones in repository depth. Especially, the groundwater table was predicted to have several tens meters below the groundwater table compared with the undisturbed condition around disposal silo after construction of underground facilities. After closure of disposal facilities, the groundwater level would be almost recovered within 1 year and have a tendency to keep a steady state of groundwater level in 2 year.

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Acoustic Emission Property and Damage Estimation of Rock Due to Cyclic Loading (반복하중 시험 시 발생하는 암석의 미소파괴음 특성과 손상도 평가)

  • Jang Hyun-Shic;Ma Yon-Sil;Jang Bo-An
    • The Journal of Engineering Geology
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    • v.16 no.3 s.49
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    • pp.235-244
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    • 2006
  • Granite cores were sampled within Korea Atomic Energy Research Institute and cyclic loadings up to 1550 cycles were applied. Microcrack development in samples due to cyclic loading was estimated using Acoustic Emission(AE) method. AE showed two different types depending on numbers of cycle. Type 1 appeared at low cycles and had low energy and diverse frequencies, while type 2 appeared at high cycles and had high energy and uniform frequency. AE property of type 1 indicates voids and pre-existing microcracks in samples may close or propagate up to certain length. Microcracks may be sheared or closed during loading and are recovered from shear or opened during unloading when AE of type 2 were measured. P wave velocities and Felicity ratios were measured at 50, 150, 350, 750, 1550 cycles. P wave velocities were almost the same regardless of number of cycles applied. However, Felicity ratios were much lower than 0.9, indicating that microcracks were developed within samples. This result indicates that Felicity ratio is a better tool than P wave velocity to estimate the damage of rock.

T-lymphocyte Inactivation and Anti-atopic Effects of Diarylheptanoid Hirsutenone Isolated from Alnus japonica (오리나무유래 디아릴헵타노이드 허수테논의 T 세포활성억제 및 항아토피 효능연구)

  • Lee, Do Ik;Seo, Seong Jun;Joo, Seong Soo
    • Korean Journal of Food Science and Technology
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    • v.45 no.4
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    • pp.508-514
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    • 2013
  • 2Department of Marine Molecular Biotechnology, College of Life Science, Gangneung-Wonju National University Recently, we reported that diarylheptanoid hirsutenone (HST) effectively inactivated T lymphocytes. However, it has not been evaluated whether HST is involved in calcineurin or calmodulin inactivation. In the present study, cells were treated with T-cell inhibitors with or without HST. Our results revealed that HST successfully inhibited expression of T-helper type I (Th1) and Th2 cytokines. Co-treatment with HST and nuclear factor-activated T cell (NFAT) activation inhibitor III (INCA-6) showed a more sensitive effect than that with other inhibitors, suggesting that HST contributes to inhibition of dephosphorylation of NFAT in the cytosol. HST up-regulated cell cycle arrest genes and inhibited the growth of Staphylococcus aureus. These effects were confirmed in an NFAT electrophoretic-mobility shift assay via successful inhibition of NFAT translocation and in the histological recovery in a 2,4-dinitrochloro benzene-induced in vivo model. Taken together, HST was shown to effectively inhibit T-cell activation via inhibition of cytosolic NFAT dephosphorylation, similar to INCA-6.