Loading [MathJax]/jax/output/CommonHTML/jax.js
  • Title/Summary/Keyword: Park construction time

Search Result 1,518, Processing Time 0.031 seconds

A Study on the Ground Reinforcement of Jeju Scoria Layer by Chemical Grouting (약액주입에 의한 제주도 송이지층의 지반보강에 관한 연구)

  • Yang, Kiho;Park, Jeongjun;Kim, Younghun;Byun, Yoseph;Lee, Eunjong;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
    • /
    • v.15 no.2
    • /
    • pp.75-82
    • /
    • 2014
  • Recently, public works becoming bigger in Jeju are implemented various kinds of ground reinforcement method including the chemical grouting method. In this study, we have been investigated on the proper material and the injection condition for the excellent injection effect and the excellent strength of injection material and the permanent waterproof and reinforcement through the experiment. The kind of injection material has been selected through the uniaxial compression test and the endurance test of injection material as the chamber test. An experiment was performed with model ground made of scoria, the injection performance of selected material has been identified through the evaluation test of injection range using the decision test of injection amount and the calibration chamber test. As a result of test, it has been analyzed that MSG appeared to have the excellent strength, durability and injection performance all compared with the ordinary cement, this result is judged to be possible as the ancillary data of design at time of design and construction with the chemical grouting method in the future.

Comparative analysis of R&D programs for societal challenges (한일 사회문제 해결형 연구개발사업 비교 분석)

  • Park, Inyong;Seong, Ji-eun;Han, Kyu-young
    • Journal of Science and Technology Studies
    • /
    • v.15 no.2
    • /
    • pp.191-227
    • /
    • 2015
  • The supply-driven innovation system is encountering its limitation. At the same time, the needs for solving societal challenges occurring in people's lives are growing. Social problem-solving R&D programs have been attracting attention as a countermeasure to satisfy these needs. It is important to understand the social context of the occurring problems as well as the users facing the social challenges. Therefore, social problem-solving R&D programs have to explore the social challenge and users' needs, with emphasis on the collaboration with researchers and users in the development and implementation process. This study carries out comparative analysis between 'Korean Citizen-driven R&D project' and 'Japanese Research institute of Science and Technology for Society (RISTEX)' concerning goals, construction of program, and promotion processes. The two cases are similar regarding the objectives of social problem-solving and the strategy for user participation. However, there are differences between the characteristics of the projects and promotion processes. The RISTEX is performing social problem-solving R&D with a much wider perspectives than the Korean project. This is because the Korean project maintained the existing R&D system with the lens of the supply-driven system, even when approaching social problem-solving. Therefore, this limitation should be overcome by adopting support systems discarding the supply-driven perspective, through substantiality of user participation, maintenance of legal system, and commercialization of technologies.

Analysis on the post-irradiation examination of the HANARO miniplate-1 irradiation test for kijang research reactor

  • Park, Jong Man;Tahk, Young Wook;Jeong, Yong Jin;Lee, Kyu Hong;Kim, Heemoon;Jung, Yang Hong;Yoo, Boung-Ok;Jin, Young Gwan;Seo, Chul Gyo;Yang, Seong Woo;Kim, Hyun Jung;Yim, Jeong Sik;Kim, Yeon Soo;Ye, Bei;Hofman, Gerard L.
    • Nuclear Engineering and Technology
    • /
    • v.49 no.5
    • /
    • pp.1044-1062
    • /
    • 2017
  • The construction project of the Kijang research reactor (KJRR), which is the second research reactor in Korea, has been launched. The KJRR was designed to use, for the first time, U-Mo fuel. Plate-type U-7 wt.% Mo/Al-5 wt.% Si, referred to as U-7Mo/Ale5Si, dispersion fuel with a uranium loading of 8.0gU/cm3, was selected to achieve higher fuel efficiency and performance than are possible when using U3Si2/Al dispersion fuel. To qualify the U-Mo fuel in terms of plate geometry, the first miniplates [HANARO Miniplate (HAMP-1)], containing U-7Mo/Al-5Si dispersion fuel (8gU/cm3), were fabricated at the Korea Atomic Energy Research Institute and recently irradiated at HANARO. The PIE (Post-irradiation Examination) results of the HAMP-1 irradiation test were analyzed in depth in order to verify the safe in-pile performance of the U-7Mo/Al-5Si dispersion fuel under the KJRR irradiation conditions. Nondestructive analyses included visual inspection, gamma spectrometric mapping, and two-dimensional measurements of the plate thickness and oxide thickness. Destructive PIE work was also carried out, focusing on characterization of the microstructural behavior using optical microscopy and scanning electron microscopy. Electron probe microanalysis was also used to measure the elemental concentrations in the interaction layer formed between the U-Mo kernels and the matrix. A blistering threshold test and a bending test were performed on the irradiated HAMP-1 miniplates that were saved from the destructive tests. Swelling evaluation of the U-Mo fuel was also conducted using two methods: plate thickness measurement and meat thickness measurement.

A Study on the Ward Module according to the External Design of the Hospital (병원 외주부 디자인에 따른 병실모듈 연구)

  • Lee, Hyunjin;Park, Wonbae
    • Journal of The Korea Institute of Healthcare Architecture
    • /
    • v.27 no.3
    • /
    • pp.71-78
    • /
    • 2021
  • Purpose: It is important to plan the ward module at a time when the size of beds, the floor area, and the construction budget are all set prior to the hospital design. In this context this study aims (1) to derive various factors affecting the ward module, and (2) to analyze the appropriate room module according to the type. Methods: Design factors related to hospital modules are derived through precedential studies, and the types of ward elevation are classified by reviewing the drawings of 18 case hospitals. And the detailed dimensions and area of the derived elements are analyzed. Results: The X-axis modules of the ward are switched to long span structural columns of 9.9 m, 12.6 m and 13.2 m, but the ward modules still represent 6.6 m. The Y-axis module of the ward shows a dimension of 9 to 9.9m in the process of changing a multi-person room into a four-person room. Type A of curtain wall with columns located on the wall of the room and type B of curtain wall located in the center of the room are analyzed due to their variations. The square window type, which forms the elevation of the square window by exposing the columns to the elevation, and the outframe type, which protrudes from the structural columns and beams, have elevation designs limited. There are, however, no obstacles to the interior space of the hospital room, so the wall composition and furniture arrangement are expected to be free. The ward area of Curtain Wall Type A, which can secure an effective area of 5.9m*5.0m, are 52.1m2. The Curtain Wall Type A, Square window type, and the outframe type are 49.8m2. Implications: As part of the hospital standard module plan for economical and reasonable hospital building planning, a type was proposed in this study in conjunction with the external design. It is hoped that it be a base for standard module research linked together to the Central Treatment department, Outpatient department and underground parking lot.

Strength Characteristics of Sedimentary Rock in Daegu-Gyungbuk Area Followed by Saturation and Crack Initiation (대구경북지역 퇴적암의 포화 및 균열 유발에 따른 강도 특성)

  • Park, Sung-Sik;Kim, Seong-Heon;Bae, Do-Han
    • Journal of the Korean Geotechnical Society
    • /
    • v.34 no.12
    • /
    • pp.29-42
    • /
    • 2018
  • Shale and mudstone in Daegu-Gyungbuk area have low strength and resistance to weathering compared to other rocks. Therefore, it is necessary to evaluate their strength depending on the degree of saturation and crack development. In this study, shales and mudstones were collected from several construction sites in Daegu-Gyungbuk area. Their basic material properties such as porosity, SEM, chemical component, and durability were tested. A porosity (absorptivity) of mudstone was 31% (25%), which was 6 (8) times higher than that of shale. Some mudstone was easily disintegrated with water and it consisted of highly-active clay mineral such as smectite type. These rocks were prepared by small cube specimens for unconfined compression test. An unconfined compressive strength of dry rock was compared with saturated one. Microwave oven was operated step by step to stimulate void water within a saturated rock, which resulted into high temperature and micro crack initiation within rocks. A strength of microwaved rocks was compared with operation time and crack initiation. As a result, the average unconfined compressive strength of dry and saturated shale was 62 and 33 MPa, respectively. The strength of mudstone for each condition was 11 and 4 MPa. When a rock became saturated, its strength decreased by 47% and 64% for shale and mudstone at average. In addition to saturation, a rock was in the microwave for 15 secs, its strength decreased into 49% for shale and 52% for mudstone. When a microwave oven operated up to 20 sec, a rock was crushed into several pieces and its temperature was approximately 200 degrees.

Application of Point Cloud Data for Transmission Power Line Monitoring (송전선 모니터링을 위한 포인트클라우드 데이터 활용)

  • Park, Joon-Kyu;Um, Dae-Yong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.11
    • /
    • pp.224-229
    • /
    • 2018
  • Korea is experiencing a rapid increase in electricity consumption due to rapid economic development, and many power transmission towers are installed to provide smooth power supply. The high-voltage transmission line is mainly made of aluminum stranded wire, and the wire is loosely guided so that some deflection is maintained. The degree of deflection has a great influence on the quality of the construction and the life of the cable. As the time passes, the shrinkage and expansion occur repeatedly due to the weight of the cable and the surrounding environment. Therefore, periodic monitoring is essential for the management of the power transmission line. In this study, the power transmission lines were monitored using 3D laser scanning technology. The data of the power transmission line of the study area was acquired and the point cloud type 3D geospatial information of the transmission line was extracted through data processing. The length of the transmission line and deflection amount were calculated using the 3D geospatial information of the transmission line, and the distance from the surrounding obstacles could be calculated effectively. The result of study shows the utilization of 3D laser scanning technology for transmission line management. Future research will contribute to the efficiency of transmission line management if a transmission line monitoring system using 3D laser scanning technology is developed.

Modeling and Simulation for Predicting the Impact of Hydraulic Breaker (유압 브레이커의 충격량 예측을 위한 모델링과 해석)

  • Kim, Sung-Hyun;Chung, Jaeho;Baek, Dong-Cheon;Park, Jong-Won
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.2
    • /
    • pp.741-749
    • /
    • 2019
  • A hydraulic breaker attached to an excavator is a kind of constructuion equipment which is used for the disassembling of buildings, crashing road pavement, breaking rocks at quarry and etc. Therefore, the performance of the hydraulic breaker is mainly evaluated by the impact quantity and impact efficiency, which is an important factor for both the manufacturer and the user. In this paper, modeling and simulation for the prediction of the impact of the hydraulic breaker was conducted according to hydraulic pressure area and operating conditions of the hydraulic valve and piston using the commercial tools SimulationX for the 20ton hydraulic breaker which is mainly used in construction site. In order to verify the reliability of modeling and simulation, the results of previous experimental studies were compared and verified. The results of this study are expected to be useful for predicting the impact of the hydraulic breaker at the design stage before manufacturing and for studying parameters for improving the impact quantity. In addition, the manufacturer predicts that the development time and cost will be reduced through trial and error prevention by predicting the impact of the hydraulic breaker through the results of this paper.

The Research report of ethnic customs in Dong-shan(東山) Yao(瑤) family (중국(中國) 광서성(廣西省) 전주현(全州縣) 동산요족(東山瑤族) 민속문화(民俗文化) 조사(調査) 약보고(略報告))

  • Park, dae-nam;Hyun, chang-ju
    • Korean Journal of Heritage: History & Science
    • /
    • v.37
    • /
    • pp.169-211
    • /
    • 2004
  • As for the "Guang-Xi(廣西)", "Dong-Shan(東山)", "Yao-Ju(瑤族)", folklore culture to achieve the substratum (New Year manners and customs, a passage rites, folk belief, dwelling folklore, agriculture and a farming machine) generally very received an influence of "Han-zu(漢族)" for the reason that an interchange was active early with "Han-zu(漢族)". However, a traditional form of "Yao-Ju(瑤族)" is covered the base with. Even if it is a national holiday commemorateing the birth of the "Pan-Gu(盤古)" which is ancestors of all "Yao-zu(瑤族)" during New Year manners and customs, songs as "ku-jia(哭嫁)" consisting at the time of marriage during a lot of ritual, "zhaoxu-hun (招婿婚)" and the "liangtou-che(兩頭扯)" marriages which are a classic marriage of "Yao-zu(瑤族)", a ritual format, master "Shi-Gong(師公)" of faith of "Yao-zu(瑤族)" are. Also, a difference is in dwelling folklore related to construction or this very much in "Han-zu(漢族)" and the various sides. It is the part where toilets to use are quite different from the Korean race in a tool, the outside written with the dwelling formal characteristics that are structure, "the ceremony of putting up the ridge beam" in, for example, two folds. Agriculture and a farming machine are basically similar to it of the Korean race, but it is a degree with some transformation by environment and the local cause.

Introduction to Current Status and Researches for Rock Engineering of Finnish Geological Disposal of Spent Fuel (핀란드의 사용후핵연료 지층처분 현황 및 암반공학 관련 연구소개)

  • Hong, Suyeon;Kwon, Saeha;Min, Ki-Bok;Park, Eui-Seob
    • Tunnel and Underground Space
    • /
    • v.29 no.4
    • /
    • pp.215-229
    • /
    • 2019
  • This technical note describes the current status of Finnish radioactive waste disposal project which started to construct the repository for spent nuclear waste for the first time in the world. Finland started operating nuclear power plant in 1977 and is currently operating four nuclear power plants. After detailed site surveys started in 1993, Olkiluoto was finally selected by the parliament of Finland as the site for geological disposal in 2001 followed by a construction license in 2015. If the operating license is approved by the government in the 2020s, it would be the world's first case of geological disposal. In ONKALO, a site-specific underground research facility at the site of Olkiluoto, various studies were conducted to verify the safety of the repository. Finland uses the KBS-3 disposal concept, and Korea considers a similar disposal concept because of similar rock formations. The entire process in Finland including the operation status of intermediate and low-level waste disposal, site investigation and selection stages, and the latest rock mechanics and hydrogeological studies in ONKALO are presented. Suggestions for the radioactive waste disposal in Korea is given based on the Finnish case.

Numerical Analysis on the Turbulence Patterns in The Scour Hole at The Downstream of Bed Protection (하상보호공 직하류부 세굴공의 난류양상에 관한 수치해석적 연구)

  • Lee, Jaelyong;Park, Sung Won;Yeom, Seongil;Ahn, Jungkyu
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.5
    • /
    • pp.20-26
    • /
    • 2019
  • Where hydraulic structures are to be installed over the entire width of a river or stream, usually a bed protection structure is to be installed. However, a local scour occurs in which the river bed downstream of the river protection system is eroded due to the influence of the upstream flow characteristics. This local scour is dominant in the flow and turbulence characteristics at the boundary of the flow direction and in the material of the bed materials, and may gradually become dangerous over time. Therefore, in this study, we compared the turbulence patterns in the local scour hole at the downstream of the river bed protection with the results of the analysis of the mobile bed experiment, and compared with the application of OpenFoam, a three dimensional numerical analysis model. The distribution of depth-averaged relative turbulence intensities along the flow direction was analyzed. In addition to this result, the stabilization of scour hole was compared with the bed shear stress and Shields parameter, and the results were compared by changing the initial turbulent flow conditions. From the results, it was confirmed that the maximum depth of generation of the three-stage was dominantly developed by the magnitude of depth-averaged relative turbulence intensity rather than the mean flow velocity. This result also suggests that design, construction or gate control are needed to control the depth-averaged relative turbulence intensities in order to reduce or prevent the local scour faults that may occur in the downstream part of the bed protection.