• Title/Summary/Keyword: Construction stage

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A Study on the Perception of the Subjects about Automated Container Terminal (컨테이너터미널 자동화에 대한 관련 주체별 인식연구)

  • You, Ji-Won;Kim, Yul-Seong
    • Journal of Navigation and Port Research
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    • v.44 no.3
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    • pp.195-202
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    • 2020
  • The production of larger of ships is a survival strategy for global shipping companies to pursue the economics of scale. According to this strategy, to respond to this situation, many containers are loading/unloading simultaneously in the hub port. Additionally, the container terminals are promoting the introduction of automation to expand the terminal facilities and increase efficiency/productivity of the container yards. European ports have introduced automation to address rising labor costs and shortages of labor. Recently, the construction of fully automated container terminals is increasing in the United States and China to resolve problems such as the slow growth of the global economy, the emergence of large ships, air pollution, and safety accidents. Domestic ports are at an early stage compared to the world's advanced container terminals, and countermeasures are being prepared to respond to the changing ports. However, research on the recognition difference analysis that examines the opinions of stakeholders is insufficient. As a result of analyzing the recognition among the groups, it was found that container terminal operators reduced labor costs, improved shipping services for shipping companies, prevented safety accidents for port union labor, and increased service for port authority and government agencies. Thus, to closely examine the perception among the groups, one-way ANOVA was performed, and then the implications were deduced as the basic data for the smooth introduction of automation.

Study of Trends in The Architecture and The Economic Efficiency of 3D Printing Technology (3D프린팅 기술의 건축분야 활용 동향과 경제성에 관한 연구)

  • Jung, Suk-Jae;Lee, Tae-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.10
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    • pp.6336-6343
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    • 2014
  • The aim of this study was to consider new 3D printing techniques and how to use them in architecture, compare the 3D printing and current techniques, and analyze them economically. 3D printing technology is expected to result in considerable changes to the entire system, such as production and distribution using this new technology in the near future. In addition, architecture is expected to follow this trend. This study examined how to take advantage of 3D printing technology in construction to prepare for a new architectural trend of 3D printing technology in the future. This study examined the 3D printing technology that is used in buildings and the current state of 3D printing technology. In addition, the 3D printing technology and current technology was also compared, and analyzed economically. 3D printing technology is the step before the stage of practical use. On the other hand, the commercialization of 3D printing technology makes it possible to reduce the cost compared to the current method. Furthermore, as the technology is developed in the future, the cost is expected to be reduced further. Therefore, the use of 3D printing technology in architecture is expected increase continually.

Study on Determination of Proper Pillar Width in Road Tunnel Design Stage (도로터널에서 적정한 필라폭 산정에 관한 연구)

  • Yang, Tae-Seon;Kim, Jae-Kyoung
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.14 no.5
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    • pp.187-194
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    • 2010
  • As the design of the pillar width (PW) of the parallel tunnels in downtown area, in which are located in plains zone with deep alluvium compared with mountain tunnels, is directly related with pre-compensation payment and costs of the underground area, it has to be planned as to keep minimum distance while securing the stability of the parallel tunnels. Although PW of downtown road tunnel in Korea is standardized as 1.5D(D: diameter of the tunnels), PW sometimes has to be reduced within 1.5D to adjust the tunnel lines to the city plan in the cases of the inlet and outlet of the tunnels. In this paper, the design and the analyses of optimum PW of the NATM type road tunnel in the downtown area are introduced. The relationship among the tunnel line planning and underground compensation fee, and ground characteristics are evaluated. In the determination of PW distance, the numerical analyses of underground road tunnels were performed, including the use of the strength decrease method and strength/stress ratio method. In the cases of inlet and outlet part of the tunnels where the stability of the pillars is poor due to contiguous construction of the parallel tunnels, the reinforcement methods are recommended for securing the stability. Numerical verification was performed for the reinforcement proposed.

Review on Soil Erosion and Loss Management System of the Calgary City Government, Albert, Canada (캐나다 앨버트 주 캘거리 시의 토사관리제도에 관한 고찰)

  • Kim, Youngchul;Kim, Lee-Hyung;Hwang, Sung Woo
    • Journal of Wetlands Research
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    • v.17 no.2
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    • pp.163-175
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    • 2015
  • In this paper, soil erosion and soil loss management system (SMS) of the City of Calgary in Albert, Canada was reviewed. Regulatory basis supporting this soil management system, permit process and conditions, guidelines and principles for the SMS, and monitoring and repair duties, inspection were discussed. Permit process in the City of Calgary is handled mainly by Urban Development Division, in which special task force called CPAG (Coorporative Planning Application Group) (if necessary circulated through related subdivisions). Inspects all the permit conditions and decides permit or refusal, and LUM (Land Use and Mobility) advertises the approval, if there is no appeals, permit is released to developers. If permit is rejected, applicant can appeals Development Appeal Board, it can approve or reject. In addition to permit, the city has manual for soil management plan, which includes BMP selection, design, monitoring, maintenance, and inspection activities. Perfect SMS policy does not necessarily guarantee relieving the soil-particle related pollution problem, but in Korea, we have to recognize that construction works during development is potentially the most destructive stage of environmental pollution. The central and local governments must make preparations for the effective and tight regulations and ordinance which is appropriate for regional social-economic conditions.

Construction of Gene-Specific Primers for Various Antioxidant Isoenzyme Genes and Their Expressions in Rice (Oryza sativa L.) Seedlings Obtained from Gamma-irradiated Seeds

  • Kim, Jin-Hon;Chung, Byung-Yeoup;Kim, Jae-Sung;Wi, Seung-Gon;Yang, Dae-Hwa;Lee, Choon-Hwan;Lee, Myung-Chul
    • Journal of Photoscience
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    • v.11 no.3
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    • pp.115-120
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    • 2004
  • For the expression study of antioxidant isoenzyme genes in rice (Oryza sativa L.) plants, extensive searches for genes of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) isoforms were performed through the GenBank database. The genes for two cytosolic and one plastidic CuZn-SOD, one Fe-SOD, two Mn-SOD, two cytosolic and two chloroplastic (stromal and thylakoid) APX, and three CAT isoforms were available in japonica-type rice. These isoforms were named as cCuZn-SOD1, cCuZn-SOD2, pCuZn-SOD, Fe-SOD, Mn-SOD1, Mn-SOD2, cAPXa, cAPXb, Chl_sAPX, Chl_tAPX, CATa, CATb, and CATc, respectively. Since they shared a high degree of homology in the nucleotide and amino acid sequences, the gene-specific primers for the genes were designed directly from their full-length cDNAs found in the database except for the CATa gene. These primers were used in the RT-PCR analysis to investigate the differential expression of antioxidant isoenzyme genes in rice plants from the seeds irradiated with low doses (2, 4, 8, and 16 Gy) of gamma-radiation. The gammairradiation slightly increased the transcripts of pCuZn-SOD, while those of Fe-SOD, cAPXb, and CATb decreased. However, no substantial differences were observed in the expression of all the isoenzyme genes between the control and irradiated groups. In this study, gene specific primers for thirteen SOD, APX and CAT isoenzymes were constructed from the full-length cDNAs. The results of RT-PCR analysis obtained by using these primers suggests that the expression levels of SOD, APX, and CAT isoenzyme genes in rice seedlings were hardly affected by gamma-irradiation at the seed stage.

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Analytical Study on Flexural Behavior of Concrete Member using Heavyweight Waste Glass as Fine Aggregate (고밀도 폐유리를 잔골재로 사용한 RC 부재의 휨거동에 관한 해석적 연구)

  • Cha, Kyoung-Moon;Choi, So-Yoeng;Kim, Il-Sun;Yang, Eun-Ik
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.24 no.1
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    • pp.88-96
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    • 2020
  • It were found that the heavyweight waste glass can be used as a construction materials including concrete from previous experimental studies. In this study, in order to evaluate the structural behavior of RC members using heavyweight waste glass as fine aggregate, a flexural behavior test was performed. And then, its results were compared with those obtained from non-linear finite element model analysis. From the results, when the heavyweight waste glass as fine aggregate in RC member, the area of compressive crushing and the number of cracks increased, however, the mean of cracking spacing decreased. Also it had reduced the ductility at high loading stage. For this reason, the same analysis method about the RC member using natural sand as fine aggregate did not predict the initial stiffness, yield load and maximum load on the flexural behavior of the RC members using heavyweight waste glass as fine aggregate. On the other hand, when it is analytically implemented the reduction of neutral axis depth due to developed compression crushing, the results of non-linear finite element analysis could be predicted the experimental results, relatively well.

Considering combined operation method with the wide area rapid-transit and high speed-transit for wide area traffic service offer at high speed track section (고속선구에 광역교통서비스 제공을 위한 고속철도와 급행전철 혼용운용 고찰)

  • Roh, Byoung-Kuk;Kim, Young-Bea;Cha, Ki-Sik
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.1900-1906
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    • 2008
  • According as zone of life of big city is expanded by new city development etc.., need special skill master plan compensation which can be systematic for wide area traffic problem solution and confusion expense minimization in the metropolitan area because wide area of capital region traffic is gone continuously and continues. Accordingly, Kyonggi Province suggested rapid-transit railway achievement that can connect Seoul Gangnam in 20 minutes with Dongtan new city recently. MLTM(Ministry of Land Transport and Maritime Affaris) announced "Capital region railway network improvement plan research services (2007.12)" result that Gangnam High-speed railway route (Suse $\sim$ Dongtan $\sim$ Pyeongtaek) construction for offer High-speed railway service to capital region and Kyonggi southern part area inhabitantses and need to line capacity tribe solution by Seoul-Busan high-speed railway second-stage and Honam high speed railroad completion. Is judged that need examination about wide area rapid-transit railway combined application operation that take advantage of rail track reserve capacity of High-speed railway for utilization efficiency elevation of country and efficient investment of national finance according as High-speed railway and Gangnam rapid-transit railway route that is suggested in Kyonggi Province are overlaped. Therefore, in this research, I wish to quote investment efficiency plan of railroad business by that different kind's train is run in uniformity track by presenting combined application operation plan and working expenses curtailment effect etc. that is optimized through analysis of roadbed and E & M technology condition, intermediate station plan, train operation planning etc. in case of wide area rapid-transit railway and high-speed railway run combined application.

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Fracture toughness of high performance concrete subjected to elevated temperatures Part 2 The effects of heating rate, exposure time and cooling rate

  • Zhang, Binsheng;Cullen, Martin;Kilpatrick, Tony
    • Advances in concrete construction
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    • v.5 no.5
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    • pp.513-537
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    • 2017
  • In this study, the fracture toughness $K_{IC}$ of high performance concrete (HPC) was investigated by conducting three-point bending tests on a total of 240 notched beams of $500mm{\times}100mm{\times}100mm$ subjected to heating temperatures up to $450^{\circ}C$ with exposure times up to 16 hours and various heating and cooling rates. For a heating rate of $3^{\circ}C/min$, $K_{IC}$ for the hot concrete sustained a monotonic decrease trend with the increasing heating temperature and exposure time, from $1.389MN/m^{1.5}$ at room temperature to $0.942MN/m^{1.5}$ at $450^{\circ}C$ for 4-hour exposure time, $0.906MN/m^{1.5}$ for 8-hour exposure time and $0.866MN/m^{1.5}$ for 16-hour exposure time. For the cold concrete, $K_{IC}$ sustained a two-stage decrease trend, dropping slowly with the heating temperature up to $150^{\circ}C$ and then rapidly down to $0.869MN/m^{1.5}$ at $450^{\circ}C$ for 4-hour exposure time, $0.812MN/m^{1.5}$ for 8-hour exposure time and $0.771MN/m^{1.5}$ for 16-hour exposure time. In general, the $K_{IC}$ values for the hot concrete up to $200^{\circ}C$ were larger than those for the cold concrete, and an inverse trend was observed thereafter. The increase in heating rate slightly decreased $K_{IC}$, and at $450^{\circ}C$ $K_{IC}$ decreased from $0.893MN/m^{1.5}$ for $1^{\circ}C/min$ to $0.839MN/m^{1.5}$ for $10^{\circ}C/min$ for the hot concrete and from $0.792MN/m^{1.5}$ for $1^{\circ}C/min$ to $0.743MN/m^{1.5}$ for $10^{\circ}C/min$ for the cold concrete after an exposure time of 16 hours. The increase in cooling rate also slightly decreased $K_{IC}$, and at $450^{\circ}C$ $K_{IC}$ decreased from $0.771MN/m^{1.5}$ for slow cooling to $0.739MN/m^{1.5}$ for fast cooling after an exposure time of 16 hours. The fracture energy-based fracture toughness $K_{IC}$' was also assessed, and similar decrease trends with the heating temperature and exposure time existed for both hot and cold concretes. The relationships of two fracture toughness parameters with the weight loss and the modulus of rapture were also evaluated.

Research on DB Construction and Utilization Measure to Analyze the Cause of Weapon System Software Engineering Change and Derive Improvement Plan (무기체계 소프트웨어 기술변경 원인분석과 개선방안 도출을 위한 데이터베이스 구축 및 활용 방안연구)

  • Oh, Jin-Woo;Kim, Jong-Kyu;Yu, Ji-seon;Yun, Jae-Hyeong;Song, Chi-Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.4
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    • pp.331-337
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    • 2021
  • Owing to the limited development period and budget of the weapon system, many problems have arisen in the operation stage after mass production. Therefore, engineering changes are also increasing. On the other hand, an analysis of the cause of problems and improvement of the system equipment performed in engineering changes cannot be managed synthetically. Hence, important actual data can only be used once. In particular, unlike hardware where the shape of the equipment is changed or the part number is changed, the contents of software engineering changes are only partially included in the proposal. Moreover, only the extent to which the version of the source package and the executable file has been changed can be identified. Therefore, this paper proposes a method to build and utilize a database for cause analysis and improvement plan data of weapon-system software engineering changes and software technical support. The above utilization measure can contribute to the quality assurance of weapon-system software developed in the future by preemptively applying real-world data when developing similar weapon systems.

Geochemical Study on the Naturally Originating Fluorine Distributed in the Area of Yongyudo and Sammokdo, Incheon (인천 용유도와 삼목도 지역 내 분포하는 자연기원 불소에 대한 지구화학적 연구)

  • Lee, Jong-Hwan;Jeong, Jong-Ok;Kim, Kun-Ki;Lee, Sang-Woo;Kim, Soon-Oh
    • Economic and Environmental Geology
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    • v.52 no.4
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    • pp.275-290
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    • 2019
  • Geochemical study was conducted to elucidate the origin of fluorine (F) distributed in the rocks within the four areas of Yongyudo and Sammokdo, Incheon, which have been used as the source area of land reclamation for the $3^{rd}$ and $4^{th}$ stage construction sites of the Incheon International Airport. The main geology of the study area is Triassic biotite granite. Fluorine is contained at high levels in biotite granite, mylonite, and dykes (andesite and, basaltic-andesite). Furthermore, the higher concentrations of fluorine in the biotite granite can be contributed to fluorite. The results of microscopic analyses reveal that the fluorite was mostly observed as small vienlets together with quartz. This features support that fluorite was naturally formed due to the secondary process of hydrothermal fluids. In addition, fluorine was investigated to be highly enriched in a large amount of mica within the veins. In the case of mylonite, a high levels of fluorine was contributed to a large amount of sericite. The sericites contained in the mylointe, differently to those of the biotite granite, filled the micro-fractures of quartz formed as a result of mylonitization and included small cataclastic quartz grains. This indicates that fluorine was naturally enriched due to the alteration of hydrothermal fluids filling fractured zones formed by mylonitization. Consequently, the results of petrological and mineralogical study confirm that the fluorine distributed in the rocks within the Yongyudo and Sammokdo originated naturally.