• 제목/요약/키워드: model systems

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A Study on the Institutional Improvement Arrangement of the Private Security in Korea (한국 민간경비 교육${\cdot}$제도의 문제점과 발전방안)

  • Gong, Bae-Wan
    • Korean Security Journal
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    • no.12
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    • pp.51-72
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    • 2006
  • Recently the demand for civil bodyguards and security guards shows rapid growth. However the supply and training system have some limitations. Educational and training systems for civil body and security guards are on the basic level and private organizations trained in the professional work force. University level training started recently. To protect individual life and property, body and security guards have to be trained professionally. For it the role of professional training organizations is emphasized. The purpose of this article is to analyse current situation of civil body and security guard training industry and to seek and educational model. For it, the following questions will be examined. ${\cdot}$ Do the professional training organizations meet social demand for the body and security guards? ${\cdot}$ What kind of training has to be provided for the body and security guards? ${\cdot}$ What are the qualifications of the trainers? ${\cdot}$ What are the differences in training courses between private organizations and universities? ${\cdot}$ Is there any differences in the job placement among the trainees of private organizations and universities? In summary to meet the social demand common curriculum for the body and security guard will be drawn from the analyses of diverse training organizations with different training courses in contents, training periods, educational value, and social aim.

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Analysis on optical pulse propagation in atomic medium for amplification without inversion (밀도 반전 없는 증폭 매질에서 광펄스 군속도의 제어 과정 분석)

  • Kim, Haeng-Hwa;Kim, Kyung-Dae;Lee, Rim;An, Moon-Hee;Kim, Joong-Bok
    • Korean Journal of Optics and Photonics
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    • v.14 no.5
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    • pp.483-490
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    • 2003
  • We have analyzed theoretically optical pulse propagation in a coherent atomic medium for amplification without inversion (AWI), which is achieved by adding incoherent optical pumping to a typical EIT system. In order to explain experimental results [Kim et al., J. Phys. B, 36, 2671(2003)] to control the group velocity of the optical pulse by changing pumping power, we established a 5-level atomic system and applied density matrix equations. This AWI model system is different from previous AWI systems from the viewpoint of using two levels for incoherent optical pumping isolated optically from the EIT (electromagentically induced transparency) system so that more atoms can participate in pulse speed control. We have found that population transfer by collisions between ground states plays a decisive role for efficient AWI, and more atoms are effective for slowing the pulse. Our numerical results are in good agreement qualitatively with experimental results.

A study on the measures to use Gunnam flood control reservoir through a reservoir simulation model (저수지 모의 모형을 통한 군남홍수조절지의 활용방안에 관한 연구)

  • Yang, Wonseok;Ahn, Jaehwang;Yi, Jaeeung
    • Journal of Korea Water Resources Association
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    • v.50 no.6
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    • pp.407-418
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    • 2017
  • Due to geographical features of being close to DPRK (Democratic People's Republic of Korea), the Imjin River basin has difficulties in hydrological observation, and is vulnerable to unexpected flood occurrence. As a countermeasure, Gunnam Flood Control Reservoir construction was planned in 2005. Despite such a structural measure, damages by DPRK's illegal release continues to occur. Futhermore the Imjin River's flow has been decreased due to the effect of continuous drought in the Korean Peninsula since 2012 and DPRK's unilateral storage of water. A new operation method is derived for the Gunnam Flood Control Reservoir in order to cope with drought damages on the Imjin River basin and to ensure efficient response time upon flooding. The operation method maintaining Gunnam Flood Control Reservoir's water level by raising from EL.23.0 m to EL.31.0 m during the flood season for securing reservoir capacity enables to secure additional $14,000,000m^3$ water compared to the existing operation methods. The operation method to store inflow by controlling release to $250m^3/s$ in the early stage of flood has increased 2.66% on average in terms of detention effect of reservoir compared to the existing operation methods. The method enables to secure 19 hours to prepare flood compared to the existing methods.

Direction-Embedded Branch Prediction based on the Analysis of Neural Network (신경망의 분석을 통한 방향 정보를 내포하는 분기 예측 기법)

  • Kwak Jong Wook;Kim Ju-Hwan;Jhon Chu Shik
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.42 no.1
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    • pp.9-26
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    • 2005
  • In the pursuit of ever higher levels of performance, recent computer systems have made use of deep pipeline, dynamic scheduling and multi-issue superscalar processor technologies. In this situations, branch prediction schemes are an essential part of modem microarchitectures because the penalty for a branch misprediction increases as pipelines deepen and the number of instructions issued per cycle increases. In this paper, we propose a novel branch prediction scheme, direction-gshare(d-gshare), to improve the prediction accuracy. At first, we model a neural network with the components that possibly affect the branch prediction accuracy, and analyze the variation of their weights based on the neural network information. Then, we newly add the component that has a high weight value to an original gshare scheme. We simulate our branch prediction scheme using Simple Scalar, a powerful event-driven simulator, and analyze the simulation results. Our results show that, compared to bimodal, two-level adaptive and gshare predictor, direction-gshare predictor(d-gshare. 3) outperforms, without additional hardware costs, by up to 4.1% and 1.5% in average for the default mont of embedded direction, and 11.8% in maximum and 3.7% in average for the optimal one.

Analyzing Site Characteristics and Suitability for Wind Farm Facilities in Forest Lands (산지 내 풍력발전단지 입지 특성 및 적합성 분석)

  • Kwon, Soon-Duk;Joo, Woo-Yeong;Kim, Won-Kyung;Kim, Jong-Ho;Kim, Eun-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.4
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    • pp.86-100
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    • 2014
  • The purposes of this study are to provide a guideline for the suitability of wind farm facilities in forest lands and to suggest improvement plans of policies and systems to minimize the damage of forest lands. First, we implemented a literature review and field surveys to examine and select factors for the suitability of wind farm facilities in forest lands. Spatial database for selected location factors of wind farm facilities in forest lands was constructed to develop the suitability model for locating wind farm facilities focusing on Gangwon-do. Data used in this study include wind power resource, legal mountainous preserved area, forest roads, developed areas, forest class, and other spatial data. In order to find specific-sized potential areas for a certain number of wind farm turbines, we used block statistics and focal statistics methods. As a result, the areas for potential wind farm locations were 1,261ha from a block statistics method and 1,411ha from a focal statistics method. Based on the outputs of this research, it is required to make an urgent solution for the prevention of forest disaster and to prepare reduction measures for the destruction of ridge landscape.

Analysis of Central Place Hierarchy Change in Daejeon Metropolitan City (대전광역시 중심지 위계 변화 분석)

  • Kim, Sang-Soo;An, Sang-Hyun;Shin, Young-Chul;Kim, Houng-Tae
    • Journal of the Korean Association of Geographic Information Studies
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    • v.11 no.3
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    • pp.23-33
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    • 2008
  • This study was performed to determine the central place hierarchy in Daejeon metropolitan city by examining its central place systems for the existing central place analyses through formation of urban spatial structure and GIS method. The central place structure and hierarch for the year of 2000 and 2005 were analyzed by using the model of W. K Davis modified, in which $1km{\times}1km$ GRID was applied. The analysis results showed the establishment of one CBD(existing center of Eunghaeng-dong and Sunhwa-dong) and two Subcenters (tourist resort of Yusung-dong and administrative center of Dunsan-dong) in Daejeon metropolitan city for the year of 2000. For the year of 2005, established were two CBD(existing center of Eunghaeng-dong and Sunhwa-dong and administrative center of Dunsan-dong) and two Subcenters (tourist resort of Yusung-dong and bus-terminal of Yongjeon) in Daejeon metropolitan city. The analysis results are expected to play a pivotal role in supporting the urban spatial policies in near future.

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Experimental Validation of Isogeometric Optimal Design (아이소-지오메트릭 형상 최적설계의 실험적 검증)

  • Choi, Myung-Jin;Yoon, Min-Ho;Cho, Seonho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.27 no.5
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    • pp.345-352
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    • 2014
  • In this paper, the CAD data for the optimal shape design obtained by isogeometric shape optimization is directly used to fabricate the specimen by using 3D printer for the experimental validation. In a conventional finite element method, the geometric approximation inherent in the mesh leads to the accuracy issue in response analysis and design sensitivity analysis. Furthermore, in the finite element based shape optimization, subsequent communication with CAD description is required in the design optimization process, which results in the loss of optimal design information during the communication. Isogeometric analysis method employs the same NURBS basis functions and control points used in CAD systems, which enables to use exact geometrical properties like normal vector and curvature information in the response analysis and design sensitivity analysis procedure. Also, it vastly simplify the design modification of complex geometries without communicating with the CAD description of geometry during design optimization process. Therefore, the information of optimal design and material volume is exactly reflected to fabricate the specimen for experimental validation. Through the design optimization examples of elasticity problem, it is experimentally shown that the optimal design has higher stiffness than the initial design. Also, the experimental results match very well with the numerical results. Using a non-contact optical 3D deformation measuring system for strain distribution, it is shown that the stress concentration is significantly alleviated in the optimal design compared with the initial design.

Validating the Structural Behavior and Response of Burj Khalifa: Synopsis of the Full Scale Structural Health Monitoring Programs

  • Abdelrazaq, Ahmad
    • International Journal of High-Rise Buildings
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    • v.1 no.1
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    • pp.37-51
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    • 2012
  • New generation of tall and complex buildings systems are now introduced that are reflective of the latest development in materials, design, sustainability, construction, and IT technologies. While the complexity in design is being overcome by the availability and advances in structural analysis tools and readily advanced software, the design of these buildings are still reliant on minimum code requirements that yet to be validated in full scale. The involvement of the author in the design and construction planning of Burj Khalifa since its inception until its completion prompted the author to conceptually develop an extensive survey and real-time structural health monitoring program to validate all the fundamental assumptions mad for the design and construction planning of the tower. The Burj Khalifa Project is the tallest structure ever built by man; the tower is 828 meters tall and comprises of 162 floors above grade and 3 basement levels. Early integration of aerodynamic shaping and wind engineering played a major role in the architectural massing and design of this multi-use tower, where mitigating and taming the dynamic wind effects was one of the most important design criteria established at the onset of the project design. Understanding the structural and foundation system behaviors of the tower are the key fundamental drivers for the development and execution of a state-of-the-art survey and structural health monitoring (SHM) programs. Therefore, the focus of this paper is to discuss the execution of the survey and real-time structural health monitoring programs to confirm the structural behavioral response of the tower during construction stage and during its service life; the monitoring programs included 1) monitoring the tower's foundation system, 2) monitoring the foundation settlement, 3) measuring the strains of the tower vertical elements, 4) measuring the wall and column vertical shortening due to elastic, shrinkage and creep effects, 5) measuring the lateral displacement of the tower under its own gravity loads (including asymmetrical effects) resulting from immediate elastic and long term creep effects, 6) measuring the building lateral movements and dynamic characteristic in real time during construction, 7) measuring the building displacements, accelerations, dynamic characteristics, and structural behavior in real time under building permanent conditions, 8) and monitoring the Pinnacle dynamic behavior and fatigue characteristics. This extensive SHM program has resulted in extensive insight into the structural response of the tower, allowed control the construction process, allowed for the evaluation of the structural response in effective and immediate manner and it allowed for immediate correlation between the measured and the predicted behavior. The survey and SHM programs developed for Burj Khalifa will with no doubt pioneer the use of new survey techniques and the execution of new SHM program concepts as part of the fundamental design of building structures. Moreover, this survey and SHM programs will be benchmarked as a model for the development of future generation of SHM programs for all critical and essential facilities, however, but with much improved devices and technologies, which are now being considered by the author for another tall and complex building development, that is presently under construction.

Communal Ontology of Landmarks for Urban Regional Navigation (도시 지역 이동을 위한 랜드마크의 공유 온톨로지 연구)

  • Hong, Il-Young
    • Journal of the Korean Geographical Society
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    • v.41 no.5 s.116
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    • pp.582-599
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    • 2006
  • Due to the growing popularity of mobile information technology, more people, especially in the general public, have access to computerized geospatial information systems for wayfinding tasks or urban navigation. One of the problems with the current services is that, whether the users are exploring or navigating, whether they are travelers who are totally new to a region or long-term residents who have a fair amount of regional knowledge, the same method is applied and the direction are given in the same way. However, spatial knowledge for a given urban region expands in proportion to residency. Urban navigation is highly dependent on cognitive mental images, which is developed through spatial experience and social communication. Thus, the wayfinding service for a regional community can be highly supported, using well-known regional places. This research is to develop the framework for urban navigation within a regional community. The concept of communal ontology is proposed to aid in urban regional navigation. The experimental work was implemented with case study to collect regional landmarks, develop the ontological model and represent it with formal structure. The final product of this study will provide the geographical information of a region to the other agent and be the fundamental information structure for cognitive urban regional navigation.

Behavioral Mechanism of Hybrid Model of ABG: Field Test (현장시험을 통한 ABG 하이브리드 공법의 거동 메커니즘 분석)

  • Seo, Hyung-Joon;Kim, Hyun-Rae;Jeong, Nam-Soo;Lee, In-Mo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.523-534
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    • 2010
  • A hybrid system of soil-nailing and compression anchor is proposed in this paper; the system is composed of an anchor bar (installed at the tip) with two PC strands and a steel bar. After drilling a hole, installing proposed hybrid systems, and filling the hole with grouting material, prestress is applied to the anchor bar to restrict the deformation at the head and/or to prevent shallow slope failures. However, since the elongation rate of PC strand is much larger than that of steel bar, yield at the steel bar will occur much earlier than the PC strand. It means that the yield load of the hybrid system will be overestimated if we simply add yield loads of the two - anchor bar and PC strands. It might be needed to try to match the yielding time of the two materials by applying the prestress to the anchor bar. It means that the main purpose of applying prestress to the anchor bar should be two-fold: to restrict the deformation at the nail head; and more importantly, to maximize the design load of the hybrid system by utilizing load transfer mechanism that transfers the prestress applied at the tip to the head through anchor bar. In order to study the load transfer mechanism in a systematic way, in-situ pullout tests were performed with the following conditions: soil-nailing only; hybrid system with the variation of prestress stresses from 0kN to 196kN. It was found that the prestress applied to the anchor system will induce the compressive stress to the steel bar; it will result in decrease in the slope of load-displacement curve of the steel bar. Then, the elongation at which the steel bar will reach yield stress might become similar to that of PC strands. By taking advantage of prestress to match elongations at yield, the pullout design load of the hybrid system can be increased up to twice that of the soil-nailing system.

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