• Title/Summary/Keyword: Space vehicles-Space vehicles

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A Study on the Inflow Velocity Reduction Measures in Case of Fire Great Depth Underground Double-Deck Tunnel (대심도 복층터널 화재 시 유입풍속 저감방안 연구)

  • Yang, Yong-Won;Moon, Jung-Joo;Shin, Tae-Gyun
    • Fire Science and Engineering
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    • v.30 no.2
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    • pp.81-86
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    • 2016
  • Recently, frequent traffic congestion has occurred in domestic urban roads. As a solution for downtown traffic congestion in domestic urban roads, plans for great depth underground double-deck tunnels have been made. Great depth underground double-deck tunnels that have been planned for passenger cars, has the structure of a network type; the entry of vehicles is carried out in the underground space. In these network great depth underground double-deck tunnels, the cross section and the height of the tunnel are smaller than the general road tunnel, and the smoke of a fire will propagate faster than the evacuation of tunnel passengers by the action of the traffic-ventilation and casualties are expected. Therefore, in the present study, an attempt was made to prevent the delay system for fire smoke diffusion at the time of a fire in a domestic network great depth underground double-deck tunnel according to the area of the tunnel block during the operation of the delay system for fire smoke diffusion to analyze the effects of reducing the inflow velocity. When the area of the tunnel block was not less than 50%, the effect of reducing about 21% of the wind speed acting on the tunnel was significant. If the area is more than 50%, the diffusion rate of fire smoke was reduced by approximately 21%, which will be useful for a safe evacuation.

Indicators and Planning Features of Ecologically Based Urban Regeneration -Cases from Hamburg, Germany and Copenhagen, Denmark (생태기반형 도시재생의 계획지표 및 특성에 관한 연구 -독일 함부르크와 덴마크 코펜하겐 사례를 중심으로)

  • Rhee, Bum-Hun;Chang, Dong-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.10
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    • pp.158-166
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    • 2018
  • Contrary to urban development, urban regeneration is a process of land development through conservation, restoration, and management. In particular, ecologically based urban regeneration is an attempt to improve the quality of life in an area, establish a stable settlement space, and revitalize the local economy by considering the ecological environment. In this regard, the objectives of this study were to establish theoretical concepts and analyze the successful foreign cases of ecologically based urban regeneration, and propose a direction of socio-economic regeneration along with the physical-environmental regeneration of urban areas in Korea. The study results suggest the following. First, strategies must be developed to coordinate public transportation, such as buses and subways, by considering the importance of bicycle riders, along with the sustainable-commuting system. Second, both the importance of planning parks and trails around water systems in various scales while maintaining the existing natural environment as well as using natural elements, such as electric vehicles and wind-power generation systems, were emphasized. Third, urban regeneration for increased energy efficiency requires specific architectural planning and facilities. Fourth, education and research for easy access by the public, as well as public-private partnership, will be needed in the regeneration process.

Information Management System of Solid Waste Landfill based on 3 Dimensional Method (3차원기법을 이용한 폐기물매립지 정보관리시스템 구축 연구)

  • Park, Jin-Kyu;Cho, Sung-Youn;Kim, Byung-Tae;Lee, Nam-Hoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.24 no.4
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    • pp.39-48
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    • 2016
  • An information management system for a solid waste landfill site was developed, in this study, to optimize the operation and management of solid waste landfill in real time in addition to provide the information of landfill status to the landfill operator, public official concerned and local residents. The landfill information management system is composed of two systems (Solid waste landfill history management system and landfill operation and performance management system). The solid waste landfill history management system based on automated RFID/LPR system allows landfill operators to provide information of waste collection vehicles and received waste. In addition, the system aids in the identification of 3-dimensional (3D) position for landfilled solid wastes. Using the landfill operation and performance management system based on 3D laser scanner delivers information about landfill volume, settlement, landfill density, and current landfill capacity to landfill operators in real time, resulting in optimum space utilization. Ultimately, this system would dramatically reduce exposure of landfill operators to hazardous materials and improve the productivity of landfill operations.

Characteristics of Planting Design according to Parking Lots Type in Multi-family Housing Complex (공동주택단지의 주차장 유형에 따른 식재특성)

  • Hong, Seong-Rae;Jeong, Dae-Young;Shim, Sang-Ryul
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.1
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    • pp.43-49
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    • 2009
  • The number of registered vehicles increased to one million in 1985 and ten million in 1997, and the parking lots in multi-family housing complex that had been mainly constructed on the ground level began to be constructed in underground levels. Therefore, planting design in such complex were greatly changed. This study classifies the parking lots in multi-family housing complexes located in Cheongju into three categories: above-ground, mixture of above-ground and underground, and underground. The characteristics of planting design in each were then analyzed. The rate of parking per family increased by two or more in the type of mixture when compared to in the type of above-ground. As underground parking lots became dominant, the rate of parking per family increased to one car or more. The green area ratio did not change considerably when above-ground parking was combined with underground parking, but the green area per total floor space was reduced, which indicates the quality of green area became lower. Most of the parking lots in multi-family housing complexes since 2000 have been constructed underground, and the green area became larger. As for the species of trees used in planting design, trees that are vulnerable to damage by blight and harmful insects and may be repugnant have been reduced and replaced by trees whose shapes are beautiful and whose flowers and fruits can be appreciated, such as Chionanthus retusa, Malus floribunda, Styrax japonicus, Prunus mume, Lagerstroemia indica. Pine trees are variously planted with diversified standards, and, in particular, tall pine trees are being utilized as focal points. Herbaceous flowers began to be planted in underground parking lots constructed since 2000, and they are expected to be planted even more due to the appreciation of their flowers and their splendid appearance.

A Study on the Coordinate-based Intersection ID Composition System Using Space Filling Curves (공간 채움 곡선을 활용한 좌표 기반의 교차로 ID 구성 체계에 관한 연구)

  • Lee, Eun il;Park, Soo hong;Kim, Duck ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.6
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    • pp.124-136
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    • 2019
  • Autonomous driving at intersections requires assistance by exchanging traffic information between traffic objects due to the intersection of various vehicles and complicated driving environment. For this reason, traffic information exchange between adjacent intersections is required, but the node ID representing the intersection in the Korean standard node link system have limitations in updating intersections and identifying location information of intersections through IDs due to the configuration system including serial numbers. In this paper, we designed a coordinate-based intersection ID configuration system created by processing and merging two-dimensional coordinates of intersections to include location information in the intersection ID. In order to verify the applicability of the proposed intersection ID, we applied a new intersection ID to domestic intersections and confirmed that there are no duplicate values. Coordinate-based intersection ID reduces data size by 60% compared to existing node ID, and enables spatial queries such as searching for nearby intersections and extracting intersections in specific areas in the form of boxes without GIS tools. Therefore, coordinate-based intersection ID is expected to be more scalable and utilized than existing node ID.

Analysis of Highway Traffic Indices Using Internet Search Data (검색 트래픽 정보를 활용한 고속도로 교통지표 분석 연구)

  • Ryu, Ingon;Lee, Jaeyoung;Park, Gyeong Chul;Choi, Keechoo;Hwang, Jun-Mun
    • Journal of Korean Society of Transportation
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    • v.33 no.1
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    • pp.14-28
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    • 2015
  • Numerous research has been conducted using internet search data since the mid-2000s. For example, Google Inc. developed a service predicting influenza patterns using the internet search data. The main objective of this study is to prove the hypothesis that highway traffic indices are similar to the internet search patterns. In order to achieve this objective, a model to predict the number of vehicles entering the expressway and space-mean speed was developed and the goodness-of-fit of the model was assessed. The results revealed several findings. First, it was shown that the Google search traffic was a good predictor for the TCS entering traffic volume model at sites with frequent commute trips, and it had a negative correlation with the TCS entering traffic volume. Second, the Naver search traffic was utilized for the TCS entering traffic volume model at sites with numerous recreational trips, and it was positively correlated with the TCS entering traffic volume. Third, it was uncovered that the VDS speed had a negative relationship with the search traffic on the time series diagram. Lastly, it was concluded that the transfer function noise time series model showed the better goodness-of-fit compared to the other time series model. It is expected that "Big Data" from the internet search data can be extensively applied in the transportation field if the sources of search traffic, time difference and aggregation units are explored in the follow-up studies.

Suggestion for the Enhancement of Military Supplies via Segregation of Defense Quality Management System (국방 분야 품질경영시스템 세분화를 통한 군수품 품질향상 방안)

  • Ju, Jin-Chun;Kim, Sung-kon;Lee, Jong-chan;Ahn, Nam-Su
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.8
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    • pp.251-261
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    • 2016
  • Recently, many weapon related quality issues have arisen in the armed forces, such as failures of K-21 Infantry Fighting Vehicles, K-9 self-propelled mounts, and grenade explosion during boot training. Since all of the issues are repetitive phenomena, we examined the defense quality management system and identified the possible solutions for it. Since the government quality assurance agency performs their quality assurance activity using the system evaluation technique, we first reviewed the regulations related to the defense quality management system. Then, we benchmarked some other advanced quality management systems. We suggested two types of defense quality management system, one for small (in terms of the amount of the contract) competitive contracts and the other for large private contracts. For the first one, we adopted the framework of MIL-I-45208 (Inspection System Requirement), while for the second one, we adopted the framework of NATO AQAP 2310 (Quality Management System Requirements for Aviation, Space and Defense Suppliers).

Mass Flow Rate Measurement of Pulsating Flow in a Twin-Scroll Turbocharger (트윈스크롤 터보과급기에서 맥동유동의 질량유량 측정)

  • Chung, Jin-Eun;Jeon, Se-Hun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.723-729
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    • 2019
  • Turbochargers are an effective device to reduce the fuel consumption. In this study, the mass flow rate of pulsating flow in the twin-scroll turbocharger for the gasoline engine of passenger vehicles was measured. Pulsating flow was achieved using a pulse generator and the mass flow rate of the unsteady pulsating flow was analyzed by comparing it with those of the steady flow. The pulse generator consisted of a rotating upper plate and a fixed lower plate. To measure the mass flow rate of unsteady flow, the orifice flow meter equipped with the difference pressure transducer was used. To analyze the low speed performance of the turbocharger, the measurement was carried out in the speed of turbocharger from 60,000rpm to 100,000rpm. The mass flow parameters of the unsteady pulsating flow showed a large difference compared to those of the steady flow. Those of the unsteady flow showed the hysteresis loop surrounding the mass flow parameters of the steady flow and the maximum variation of the mass flow parameters were 5.0 times those of the steady flow. This phenomenon is the result of the filling and emptying the turbine volute space due to pulsating flow.

Determination of Dimension of Vertical Curve Elements at Parking Lot Ramps (주차장 램프의 종단곡선 제원 산정에 관한 연구)

  • Kwon, Sung-Dae;Kim, Yoon-Mi;Hong, Jeong-Pyo;Ha, Tae-Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.3
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    • pp.607-616
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    • 2015
  • The demand for cars has been so steadily increasing based on the economic growth that the number of registered cars reached 18,870,000 as of the end of December, 2012. Due to this, the demand for the parking lots also rises continuously. Because of the limited ground space, the buildings ever becoming larger, and the trend of underground parking spaces, recent parking spaces are generally constructed underground. Accordingly, the parking lot ramps slope is limited to less than 17% by relevant laws to ensure the driver safety. However, when a driver enters a parking lot ramps whose slope is slightly steep, he frequently experiences his car body colliding with ramp brackets and often sees the scratches on ramp floor. Thus, this study is intended to prevent any damage to a structure and to contribute to ensuring the riding comfort and safety of drivers and passengers by presenting the details of proper vertical curve to prevent the collision of vehicles with ramp brackets through a vertical analysis of the first and last parts of a parking lot ramps. Because it is necessary to decide the appropriate and suitable vertical slope of a parking lot ramps, this study first identified the problems through site inspection, targeting the parking lot ramps of large buildings frequently that are used by many random people. Next, the possibility of mutual collision was assessed through a theoretical analysis of the first and last parts of a parking lot ramps. Lastly, the vertical curve of a parking ramp was analyzed to estimate its details, which was presented in this study. In conclusion, if the vertical curve presented through this study is used, it will help prevent any damage to the cars and structures, ensure the riding comfort and safety of the drivers, and further reestablish the criteria for vertical installation of a parking lot ramps.

Comparative Analysis of pre and Post Digital X-ray Equipment Construction and Web-Based Wireless Network Environment Construction for Medical Screening Vehicles (Digital X-ray장비 구축 검진차량의 웹 기반 무선 네트워크 환경 구축 전과 후의 비교분석)

  • Ryu, Young-Hwan;Kweon, Dae-Cheol;Goo, Eun-Hoe;Dong, Kyung-Rae;Choi, Sung-Hyun;Jang, Young-Ill
    • Korean Journal of Digital Imaging in Medicine
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    • v.12 no.2
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    • pp.103-111
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    • 2010
  • A total of 200 hospital employees participated in this study from January 2009 to June 2010. For the survey, each participant was given necessary items for external health exams. Cronbach's alpha was calculated for the survey regarding wireless networks. There was a need for educating data processing workers in the medical field regarding fundamental information prior to wireless network construction. The reason is high scores would be collected, which would reflect knowledge regarding data processing used at hospitals and the differences between paper charts and electronic charts. However, low scores were obtained which reflected knowledge regarding the differences between wired and wireless networks and Mini-PACS. Time for each patient was shortened to a maximum of three minutes and minimum of one minute for treatment and transmitting medical images when comparing pre and post wireless network construction(p < 0.01). Scores from the pre and post construction survey increase 1.98, 1.65, and 1.43 points for activity in the health screening area, usage of space in the health screening vehicle, and patient information storage respectively(p < 0.05). The number of patients receiving external health screenings twelve times was 3,655 prior to construction of a wireless network system. However, the number increased to 4,265 after construction. The increasing percentage was 17% in total. Prior to construction, X-ray images were taken 527 times, but after construction of a wireless network, this number growed to 1,194 and it was 116% increase. The loss of patient's medical treatment charts was reduced from 19.8% to 18.7% after construction. We believe that educating medical workers on Mini-PACS and Mini-OCS Systems will not only increase their efficiency but also make patients receiving better treatment.

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