• 제목/요약/키워드: large space

Search Result 4,172, Processing Time 0.029 seconds

Agent Model Construction Methods for Simulatable CPS Configuration (시뮬레이션 가능한 CPS 구성을 위한 에이전트 모델 구성 방법)

  • Jinmyeong Lee;Hong-Sun Park;Chan-Woo Kim;Bong Gu Kang
    • Journal of the Korea Society for Simulation
    • /
    • v.33 no.2
    • /
    • pp.1-11
    • /
    • 2024
  • A cyber-physical system is a technology that connects the physical systems of a manufacturing environment with a cyber space to enable simulation. One of the major challenges in this technology is the seamless communication between these two environments. In complex manufacturing processes, it is crucial to adapt to various protocols of manufacturing equipment and ensure the transmission and reception of a large volume of data without delays or errors. In this study, we propose a method for constructing agent models for real-time simulation-capable cyberphysical systems. To achieve this, we design data collection units as independent agent models and effectively integrate them with existing simulation tools to develop the overall system architecture. To validate the proposed structure and ensure reliability, we conducted empirical testing by integrating various equipment from a real-world smart microfactory system to assess the data collection capabilities. The experiments involved testing data delay and data gaps related to data collection cycles. As a result, the proposed approach demonstrates flexibility by enabling the application of various internal data collection methods and accommodating different data formats and communication protocols for various equipment with relatively low communication delays. Consequently, it is expected that this approach will promote innovation in the manufacturing industry, enhance production line efficiency, and contribute to cost savings in maintenance.

Capabilities Required for Underground Facility Operations in Korean Megacities (한국 메가시티 지하시설 작전에 요구되는 능력)

  • Jun Hak Sim;Seung Jin Jo;Jun Woo Kim;Ji Woong Choi;Won Jun Choi;Sun Il Yang;Sang Hyuk Park
    • The Journal of the Convergence on Culture Technology
    • /
    • v.10 no.2
    • /
    • pp.267-272
    • /
    • 2024
  • Recently, major advanced countries are fostering megacities through policy for reasons such as solving population problems, political and economic issues, and strengthening national competitiveness. The trend of change is accelerating. In Korea, following Seoul and Gyeonggi, mega city policies are being promoted in Busan, Ulsan, Gyeongnam, Daegu and Gyeongbuk, Gwangju and Jeonnam, and Daejeon, Sejong, South Chungcheong and North Chungcheong areas. Due to this urbanization phenomenon, military experts predict that the future battlefield environment will be space or a large city (mega city). From this perspective, Korea will not be able to effectively respond to the threats facing megacities if it does not prepare in advance. Therefore, underground facility operation capabilities optimized for the huge scale of the mega city and the characteristics of the underground operational environment are required. Against this background, the characteristics of the underground operational environment of mega cities and cases of preparation for underground facility operations in advanced military countries such as the United States and Israel were analyzed. Based on this, the capabilities required for underground facility operations suitable for the underground operational environment within Korean megacities are developed from an idea perspective to military organization and combat system, securing special equipment and materials to ensure combatant survival, developing small unit combat techniques, and establishing a training system. It was presented with priority given to.

Field Applicability Evaluation Experiment for Ultra-high Strength (130MPa) Concrete (초고강도(130MPa) 콘크리트의 현장적용성 평가에 관한 실험)

  • Choonhwan Cho
    • Journal of the Society of Disaster Information
    • /
    • v.20 no.1
    • /
    • pp.20-31
    • /
    • 2024
  • Purpose: Research and development of high-strength concrete enables high-rise buildings and reduces the self-weight of the structure by reducing the cross-section, thereby reducing the thickness of beams and slabs to build more floors. A large effective space can be secured and the amount of reinforcement and concrete used to designate the base surface can be reduced. Method: In terms of field construction and quality, the effect of reducing the occurrence of drying shrinkage can be confirmed by studying the combination of low water bonding ratio and minimizing bleeding on the concrete surface. Result: The ease of site construction was confirmed due to the high self-charging property due to the increased fluidity by using high-performance water reducing agents, and the advantage of shortening the time to remove the formwork by expressing the early strength of concrete was confirmed. These experimental results show that the field application of ultra-high-strength concrete with a design standard strength of 100 MPa or higher can be expanded in high-rise buildings. Through this study, we experimented and evaluated whether ultra-high-strength concrete with a strength of 130 MPa or higher, considering the applicability of high-rise buildings with more than 120 floors in Korea, could be applied in the field. Conclusion: This study found the optimal mixing ratio studied by various methods of indoor basic experiments to confirm the applicability of ultra-high strength, produced 130MPa ultra-high strength concrete at a ready-mixed concrete factory similar to the real size, and tested the applicability of concrete to the fluidity and strength expression and hydration heat.

Zirconia removable prosthesis using a milled bar in patient with mandible anterior edentulous area with severe alveolar bone resorption: a case report (치조골 흡수가 심한 하악 전치부 부분 무치악 환자에서 Milled-bar를 이용한 지르코니아 가철성 보철물 수복 증례)

  • Jin-Young Park;Chang-Mo Jeong;Mi-Jung Yun;Jung-Bo Huh;So-Hyoun Lee;Dae-Sung Kim
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.62 no.3
    • /
    • pp.193-200
    • /
    • 2024
  • In patients with severe alveolar bone resorption on mandibular anterior edentulous areas, it can be difficult to place implants in the location for crowns, and to create the fixed prosthesis having an adequate emergence profile or embrasure, which makes maintenance difficult. Fabricating a removable zirconia prosthesis with a milled bar on poorly positioned implants can be a good option because of easy maintenance. In this case, the patient had severe bone resorption on mandibular anterior region, and large vertical space. We report on the aesthetical and easy-to-maintain results by placing two implants and fabricating a zirconia prosthesis using milled bar.

Analysis of Joint Characteristics and Rock Mass Classification using Deep Borehole and Geophysical Logging (심부 시추공 회수코어와 물리검층 자료를 활용한 절리 및 암반등급 평가)

  • Dae-Sung Cheon;Seungbeom Choi;Won-Kyong Song;Seong Kon Lee
    • Tunnel and Underground Space
    • /
    • v.34 no.4
    • /
    • pp.330-354
    • /
    • 2024
  • In site characterization of high-level radioactive waste, discontinuity(joint) distribution and rock mass classification, which are key evaluation parameters in the rock engineering field, were evaluated using deep boreholes in the Wonju granite and Chuncheon granite, which belong to Mesozoic Jurassic era. To evaluate joint distribution characteristics, fracture zones and joint surfaces extracted from ATV data were used, and major joint sets were evaluated along with joint frequency according to depth, dip direction, and dip. Both the Wonju and Chuncheon granites that were studied showed a tendency for the frequency of joints to increase linearly with depth, and joints with high angles were relatively widely distributed. In addition, relatively large amounts of weathering tended to occur even in deep depth due to groundwater inflow through high-angle joints. RQD values remained consistently low even at considerable depth. Meanwhile, joint groups with low angles showed different joint characteristics from joint sets with high angles. Rock mass classification was performed based on RMR system, and along with rock mass classification for 50 m intervals where uniaxial compressive strength was performed, continuous rock mass classification according to depth was performed using velocity log data and geostatistical techniques. The Wonju granite exhibited a superior rock mass class compared to the Chuncheon granite. In the 50 m interval and continuous rock mass classification, the shallow part of the Wonju granite showed a higher class than the deep part, and the deep part of the Chuncheon granite showed a higher class than the shallow part.

PRC Maritime Operational Capability and the Task for the ROK Military (중국군의 해양작전능력과 한국군의 과제)

  • Kim, Min-Seok
    • Strategy21
    • /
    • s.33
    • /
    • pp.65-112
    • /
    • 2014
  • Recent trends show that the PRC has stepped aside its "army-centered approach" and placed greater emphasis on its Navy and Air Force for a wider range of operations, thereby reducing its ground force and harnessing its economic power and military technology into naval development. A quantitative growth of the PLA Navy itself is no surprise as this is not a recent phenomenon. Now is the time to pay closer attention to the level of PRC naval force's performance and the extent of its warfighting capacity in the maritime domain. It is also worth asking what China can do with its widening naval power foundation. In short, it is time to delve into several possible scenarios I which the PRC poses a real threat. With this in mind, in Section Two the paper seeks to observe the construction progress of PRC's naval power and its future prospects up to the year 2020, and categorize time frame according to its major force improvement trends. By analyzing qualitative improvements made over time, such as the scale of investment and the number of ships compared to increase in displacement (tonnage), this paper attempts to identify salient features in the construction of naval power. Chapter Three sets out performance evaluation on each type of PRC naval ships as well as capabilities of the Navy, Air Force, the Second Artillery (i.e., strategic missile forces) and satellites that could support maritime warfare. Finall, the concluding chapter estimates the PRC's maritime warfighting capability as anticipated in respective conflict scenarios, and considers its impact on the Korean Peninsula and proposes the directions ROK should steer in response. First of all, since the 1980s the PRC navy has undergone transitions as the focus of its military strategic outlook shifted from ground warfare to maritime warfare, and within 30 years of its effort to construct naval power while greatly reducing the size of its ground forces, the PRC has succeeded in building its naval power next to the U.S.'s in the world in terms of number, with acquisition of an aircraft carrier, Chinese-version of the Aegis, submarines and so on. The PRC also enjoys great potentials to qualitatively develop its forces such as indigenous aircraft carriers, next-generation strategic submarines, next-generation destroyers and so forth, which is possible because the PRC has accumulated its independent production capabilities in the process of its 30-year-long efforts. Secondly, one could argue that ROK still has its chances of coping with the PRC in naval power since, despite its continuous efforts, many estimate that the PRC naval force is roughly ten or more years behind that of superpowers such as the U.S., on areas including radar detection capability, EW capability, C4I and data-link systems, doctrines on force employment as well as tactics, and such gap cannot be easily overcome. The most probable scenarios involving the PRC in sea areas surrounding the Korean Peninsula are: first, upon the outbreak of war in the peninsula, the PRC may pursue military intervention through sea, thereby undermining efforts of the ROK-U.S. combined operations; second, ROK-PRC or PRC-Japan conflicts over maritime jurisdiction or ownership over the Senkaku/Diaoyu islands could inflict damage to ROK territorial sovereignty or economic gains. The PRC would likely attempt to resolve the conflict employing blitzkrieg tactics before U.S. forces arrive on the scene, while at the same time delaying and denying access of the incoming U.S. forces. If this proves unattainable, the PRC could take a course of action adopting "long-term attrition warfare," thus weakening its enemy's sustainability. All in all, thiss paper makes three proposals on how the ROK should respond. First, modern warfare as well as the emergent future warfare demonstrates that the center stage of battle is no longer the domestic territory, but rather further away into the sea and space. In this respect, the ROKN should take advantage of the distinct feature of battle space on the peninsula, which is surrounded by the seas, and obtain capabilities to intercept more than 50 percent of the enemy's ballistic missiles, including those of North Korea. In tandem with this capacity, employment of a large scale of UAV/F Carrier for Kill Chain operations should enhance effectiveness. This is because conditions are more favorable to defend from sea, on matters concerning accuracy rates against enemy targets, minimized threat of friendly damage, and cost effectiveness. Second, to maintain readiness for a North Korean crisis where timely deployment of US forces is not possible, the ROKN ought to obtain capabilities to hold the enemy attack at bay while deterring PRC naval intervention. It is also argued that ROKN should strengthen its power so as to protect national interests in the seas surrounding the peninsula without support from the USN, should ROK-PRC or ROK-Japan conflict arise concerning maritime jurisprudence. Third, the ROK should fortify infrastructures for independent construction of naval power and expand its R&D efforts, and for this purpose, the ROK should make the most of the advantages stemming from the ROK-U.S. alliance inducing active support from the United States. The rationale behind this argument is that while it is strategically effective to rely on alliance or jump on the bandwagon, the ultimate goal is always to acquire an independent response capability as much as possible.

A Study of Urban Park Development and Management through Public-Private Partnership (민.관 파트너십 도시공원 조성 및 관리방식 연구)

  • Kim, Yong-Gook;Han, So-Young;Zoh, Kyung-Jin
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.39 no.3
    • /
    • pp.83-97
    • /
    • 2011
  • The purpose of this study is to perform a gap analysis between public-private partnership urban parks of Korea currently in their initial stage and various foreign cases that have been established in terms of planning(formation of public-private partnership${\rightarrow}$creation of parks${\rightarrow}$operation and management of parks) and to propose improvements for each process of planning. As a result of the gap analysis on domestic and foreign public-private partnership urban parks, the future course to be followed by urban Korean parks can be summarized as follows. First, if the public-private urban parks that exist at present were led by a single or small number of partners centered on local government entities, urban parks from that point on must be created and managed based on efficient multi-sector partnerships. Since urban parks are public spaces where public benefit is more important than profit, diverse voices of public-private sectors must be reflected with a long-term perspective. Second, urban parks are not a place to be completed but a public space which continues to develop. Therefore, they must be approached with a focus on the process instead of the result. The existing concept of domestic public-private partnership is inclined to creation of urban parks. This suggests than the government had been focusing only on quantitative increase in urban parks. In order to create values as a public space for local communities, public-private partnership is also required in operation and management of urban parks. Third, public-private partnership management of urban parks can become more effective through active community participation. Participation by local communities takes long time because transition in the consciousness about values of urban parks must be presumed. Thus in Korea, non-profit organization like Seoul Green Trust should accumulate successful creation and management of small and large urban parks through public-private partnership will settle in our nation.

A Comparative Study on the Awareness of Concepts for Gardens and Parks between the Experts and General Publics (정원과 공원에 대한 전문가와 일반인 인식 비교 연구)

  • Miok, Park
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.46 no.5
    • /
    • pp.1-9
    • /
    • 2018
  • The purpose of this study was to identify differences of perceptions for gardens and parks between experts and the general public concerning several aspects including scope, scale, publicity, artistic and scientific nature, main materials, practicality and aesthetics, executive and management systems as well as legal understanding of garden and park. The properties of garden and park were derived through literature research, and the concept, similarity, and difference of gardens and the parks were recognized by the experts and the public viewpoint was clarified by questionnaire. As for the difference in the scope of the gardens and the parks, the expert group recognized it more widely than the general public. In general, the space recognized as a garden was the rooftop green space, and urban forests were recognized as a park. In addition, the general public recognized urban forests as gardens the same as they recognized parks, and the distinction was unclear. In the expert group, the perception that gardens were small and the parks were large was more prevalent. It was generally recognized that gardens were private spaces and the parks were public spaces. In the expert group, the gardens were more personal and the parks were more apparent to the public. In the general population, functional and scientific aspects rather than artistic creativity in both gardens and parks. In addition, both the general public and experts found that parks are more complex than gardens. The garden was centered on plant material, and the park was recognized as a center where the sculptural facilities were centered, or the plant material and the sculptural facilities were properly balanced. To the experts the view of the gardens was positive. Expert groups emphasized the aesthetics of the garden, and the parks were more practical, and the general population showed similar perceptions of utility and aesthetics when comparing gardens and parks. In addition, the utility of gardens in the general publics is more emphasized than the aesthetics of the park. Regarding the executive system the park was recognized as the public sector, and the difference was larger in the expert group. As for the management system, both experts and the general public perceive the management of the park or the garden to be carried out by the supporting organization, and it is necessary to discuss the diversification of the management subject. It is found that there is a certain difference in recognition with the mixture of concepts, and there is still a big difference in legal system and perception.

Determination of Equivalent Hydraulic Conductivity of Rock Mass Using Three-Dimensional Discontinuity Network (삼차원 불연속면 연결망을 이용한 암반의 등가수리전도도 결정에 대한 연구)

  • 방상혁;전석원;최종근
    • Tunnel and Underground Space
    • /
    • v.13 no.1
    • /
    • pp.52-63
    • /
    • 2003
  • Discontinuities such as faults, fractures and joints in rock mass play the dominant role in the mechanical and hydraulic properties of the rock mass. The key factors that influence on the flow of groundwater are hydraulic and geometric characteristics of discontinuities and their connectivity. In this study, a program that analyzes groundwater flow in the 3D discontinuity network was developed on the assumption that the discontinuity characteristics such as density, trace length, orientation and aperture have particular distribution functions. This program generates discontinuities in a three-dimensional space and analyzes their connectivity and groundwater flow. Due to the limited computing capacity In this study, REV was not exactly determined, but it was inferred to be greater than 25$\times$25$\times$25 ㎥. By calculating the extent of aperture that influences on the groundwater flow, it was found that the discontinuities with the aperture smaller than 30% of the mean aperture had little influence on the groundwater flow. In addition, there was little difference in the equivalent hydraulic conductivity for the the two cases when considering and not considering the boundary effect. It was because the groundwater flow was mostly influenced by the discontinuities with large aperture. Among the parameters considered in this study, the length, aperture, and orientation of discontinuities had the greatest influence on the equivalent hydraulic conductivity of rock mass in their order. In case of existence of a fault in rock mass, elements of the equivalent hydraulic conductivity tensor parallel to the fault fairly increased in their magnitude but those perpendicular to the fault were increased in a very small amount at the first stage and then converged.

ALL-SKY OBSERVATION OF THE 2001 LEONID METEOR STORM: 1. METEOR MAGNITUDE DISTRIBUTION (전천 카메라를 이용한 2001 사자자리 유성우 관측: 1. 유성 등급 분포)

  • 김정한;정종균;김용하;원영인;천무영;임홍서
    • Journal of Astronomy and Space Sciences
    • /
    • v.20 no.4
    • /
    • pp.283-298
    • /
    • 2003
  • The 2001 Leonid meteor storm has been observed all over the world, and its most intense flux since the last few decades has caused great interest among both laymen and experts. Especially, its maximum hours occurred at dawn hours of Nov. 19 in the east Asia, during which moonless clear night at the Mt. Bohyun allowed us near perfect condition of observation. Observation was carried out in the period of 01:00∼05:40(KST), which include the predicted maximum hours, with all-sky camera installed for upper atmospheric airglow research. Tn this paper we analyze 68 all-sky images obtained in this period, which contain records of 172 meteors. Utilizing the zenith hourly rate(ZHR) of 3000 and magnitude distribution index of 2, which were reported to International Meteor Organization by visible observers in the east Asia, we estimate the limiting magnitude of about 3 for meteors detected in our all-sky images. We then derive magnitudes of 83 meteors with clear pixel brightness outlines among the initially detected 172 meteors by comparing with neighbor standard stars. Angular velocities of meteors needed for computing their passing times over an all-sky image are expressed with a simple formula of an angle between a meteor head and the Leonid radiant point. The derived magnitudes of 83 meteors are in the range of -6∼-1 magnitude, and its distribution shows a maximum new -3mag. The derived magnitudes are much smaller than the limiting magnitude inferred from the comparison with the result of naked-eye observations. The difference may be due to the characteristic difference between nearly instantaneuous naked-eye observations and CCD observations with a long exposure. We redetermine magnitudes of the meteors by adjusting a meteor lasting time to be consistent with the naked-eye observations. The relative distribution of the redetermined magnitudes, which has a maximum at 0 mag., resembles that of the magnitudes determined with the in-principle method. The relative distribution is quite different from ones that decrease monotonically with decreasing magnitudes for meteors(1∼6) sensitive to naked-eye observations. We conclude from the magnitude distribution of our all-sky observation that meteors brighter than about 0 mag., appeared more frequently during the 2001 Leonid maximum hours. The frequent appearance of bright meteors has significantly important implication for meteor research. We noted, however, considerably large uncertainties in magnitudes determined only by comparing standard stars due to the unknown lasting time of meteors and the non-linear sensitivity of all-sky camera.