• 제목/요약/키워드: Observational method

검색결과 314건 처리시간 0.023초

지반과 관련된 지난 세기의 건설사고와 정보화 시공 (A Review of the Last Century Construction Failures and the Observational Method in Geotechnical Engineering)

  • 김학문
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 봄 학술세미나 논문집
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    • pp.1-36
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    • 2000
  • Construction incidents, mechanisms and causes in Geotechnical Engineering have been closely reviewed for the safety assurance during design and construction stages. The safety assurance is clearly related to the observational method in which design is reviewed during construction and contingency actions are undertaken successfully to minimise any potential failures. The observational method has been extensively applied for the construction of subways underground structures, dams and many important Civil Engineering projects in the past 20 years. But the number of serious construction incidents are growing for the past several decades. Therefore present development of observational method and improvement techniques are introduced with some case histories.

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Angles-Only Initial Orbit Determination of Low Earth Orbit (LEO) Satellites Using Real Observational Data

  • Hwang, Hyewon;Park, Sang-Young;Lee, Eunji
    • Journal of Astronomy and Space Sciences
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    • 제36권3호
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    • pp.187-197
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    • 2019
  • The Optical Wide-field patroL-Network (OWL-Net) is a Korean optical space surveillance system used to track and monitor objects in space. In this study, the characteristics of four Initial Orbit Determination (IOD) methods were analyzed using artificial observational data from Low Earth Orbit satellites, and an appropriate IOD method was selected for use as the initial value of Precise Orbit Determination using OWL-Net data. Various simulations were performed according to the properties of observational data, such as noise level and observational time interval, to confirm the characteristics of the IOD methods. The IOD results produced via the OWL-Net observational data were then compared with Two Line Elements data to verify the accuracy of each IOD method. This paper, thus, suggests the best method for IOD, according to the properties of angles-only data, for use even when the ephemeris of a satellite is unknown.

지각불편도를 이용한 관찰적 작업자세 평가 기법의 비교 (Comparison of observational posture evaluation methods based on perceived discomfort)

  • 이인석;정민근;최경임
    • 대한인간공학회지
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    • 제22권1호
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    • pp.43-56
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    • 2003
  • Observational methods such as OWAS, RULA, and REBA have been widely used to identify posture-related risks of musculoskeletal disorders in industry, since they are useful and efficient in evaluating postural stresses. However. there are few studies comparing the methods and providing guidelines for selecting and using the methods. They have been developed based on different backgrounds and with different application areas. Each method has its own characteristics. which must be considered in selecting and using them. In this study. 17 male subjects evaluated 42 different working postures that frequently assumed in the automobile assembly line using a psychophysical method. The postures were then evaluated by different observational methods. The results of the observational methods were compared with psychophysically evaluated stresses. The observational methods resulted in different values of stresses for certain postures. For some postures showing high values of perceived discomfort. the observational methods showed different values of stresses. These results showed that the observational methods should be used differently according to application area and they have some weak points to be improved.

정보화 시공에서 Feed Back Analysis (터널, 암반사면, 지반굴착 등 Hard Material 사례중심으로) (The Role of Feed Back Analysis in Observational Method)

  • 김학문
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 가을 학술발표회 논문집
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    • pp.147-179
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    • 2002
  • The important role of observational method in geotechnical engineering are emphasized together with the direction of future development, concerning successful application of the technique on the site investigation, design and feed back at various construction stages. Case histories on the application of feed back are introduced in order to achieve the most economical and reliable construction for tunnel, rock slope and deep excavations through feed back system at design and construction stages. Also the limitations and advantages of the observational method and the role of feed back system are discussed for construction of tunnel, rock slope and deep excavation in hard ground such as layered ground conditions including weathered, soft and hard rocks.

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불연속성 암반에서의 터널의 암반블럭 평가를 위한 신 정보화설계시공법 (New Observational Design and Construction Method for Rock Block Evaluation of Tunnels in Discontinuous Rock Masses)

  • 황재윤
    • 터널과지하공간
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    • 제16권1호
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    • pp.1-10
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    • 2006
  • 실제 암반에는 단층, 절리, 층리, 균열, 단열, 편리, 벽개 등의 불연속면이 많이 포함되어 있다. 따라서, 불연속면이 암반구조물의 거동을 좌우하고 있다. 암반구조의 복잡성으로 인해 사전에 예측 할 수 없었던 암반의 붕락이 발생하여, 붕락대책에 막대한 비용과 시간을 낭비하는 사례가 많다. 암반 불연속면의 복잡성을 사전 조사단계에서 충분히 파악하거나 대책을 수립하는 것은 어렵다. 최근 터널의 정보화 설계시공이 중요시되어지고 있다. 본 논문에서는 불연속성 암반에서의 터널의 신 정보화 설계시공법을 제안하고, 현지에서 관찰한 불연속면 정보를 근거로 하여 실제 터널현장에 적용했다. 실제 터널현장에 있어서, 터널의 신 정보화 설계시공법을 위해서 새롭게 개발한 수치해석 프로그램을 사용하여 정확한 키블럭 추출이 가능하였다. 사용하기 쉬운 사용자 인터페이스를 가지고 있는 본 컴퓨터 시뮬레이션 기법은 암반블럭의 안정성 계산뿐만 아니라 추가 보강대책공의 설계도 가능하다. 터널 굴착중에 키블럭을 확인하므로써, 제안한 신 정보화 설계시공법의 유효성에 대한 검증을 하였다.

터널의 정보화 설계시공을 위한 키블럭 해석기법 (Key block analysis method for observational design and construction method in tunnels)

  • 황재윤
    • 한국터널지하공간학회 논문집
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    • 제12권3호
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    • pp.275-283
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    • 2010
  • 최근 터널의 정보화 설계시공이 중요시 되어지고 있다. 암반에는 절리, 단층, 균열, 층리, 단열 등의 불연속면이 많이 포함되어 있다. 따라서, 암반 불연속면이 터널의 거동을 좌우하고 있다. 본 연구에서는 터널의 정보화 설계시공을 위한 키블럭 해석기법을 제안하고, 초대단면 터널현장에 적용했다. 제안한 해석기법은 불연속면의 연속성을 고려하여, 블록의 형상에 관계없이 모든 형상의 블록이 인식 가능하여 복잡한 굴착면에 적용가능하다. 터널현장에서의 해석결과를 비교 검토하여, 본 연구에서 개발한 터널의 정보화 설계시공을 위한 키블럭 해석기법의 타당성과 적용성에 대한 검증을 하였다.

간호학생의 분만관찰경험 (The Observational Experience of Labor and Delivery by Student Nurses in the Clinical Setting)

  • 고명숙
    • 대한간호학회지
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    • 제27권4호
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    • pp.892-900
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    • 1997
  • The purpose of this study was to use phenomenological perspectives to identify the meaning and structure of the observational experience of labor and delivery by student nurses in the clinical setting. The participants were 115 junior and senior students from Christian College of Nursing in Kwang Ju. The students were asked to write about their observational experience in the delivery room. Colaizzi's method was used for phenomenological analysis. The investigator analysed the data to identify and categorize themes and basic structural elements. Twelve themes and eight basic structure were identified. The process of the observational experience in labor and delivery has three proposed phases : anticipatory, observational and post-observational. In the anticipatory phase, nursing students were related only to the event of anticipated labor and delivery of clients. Structure 1, feeling of expectation and fear, was identified. In the observational phase, students were related to the labor and delivery situation, a woman delivered and a newborn. Structure 2, shock and suffering, was identified in relation to the labor and delivery situation. Structure 3, need for caring and satisfaction, was identified in relation to the woman delivered. Structure 4, feeling of mystery and joy, was identified in relation to the newborn. In the post-observational phase, relations between students and the life of a human being, students and self in the future, students and their mothers and students and women and God appeared. And in these relations 〈structure 5, valuable〉, 〈structure 6, feeling of expectation and fear〉, 〈structure 7, love and appreciation〉 and 〈structure 8, greatness〉 were identified.

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지반공학 분야의 국외 정보화 시공기술 적용 사례 및 발전 방향 (New Technologies and Development in Observational Methods and Research Needs in Geotechnical Engineering)

  • 유충식
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 봄 학술세미나 논문집
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    • pp.37-54
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    • 2000
  • The observational method using field measurement technique have contributed significantly to advancements in the state-of-the art of geotechnical engineering in the 20th century. Due to the rapid development in computer technology, Internet and GIS have become an integral part of civil engineering project management. This paper presents new technologies and development in observational method which have valuable implication on field measurement in geotechnical engineering. Systematic approach to planning monitoring program in geotechnical instrumentation is also presented. Finally, research needs in development and application of integrated design/construction management system in geotechnical engineering projects are discussed.

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이상치를 이용한 관측적 침하예측기법의 개발 (Development of a Observational Settlement Analysis Method Using Outliers)

  • 우철웅;장병욱
    • 한국농공학회지
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    • 제45권5호
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    • pp.140-150
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    • 2003
  • Observational methods such as the Asaoka's method and the hyperbolic method are widely applied on the settlement analysis using observed settlement. The most unreliable aspects in those methods is arose from the subjective discretion of initial non-linearity on linear regression. The initial non-linearity is inevitable due to the settlement behaviour itself. Therefore an objective method is essential to achieve more reliable results on settlement analysis. It was found that the initial non-linear data are statistical outliers. New automation algorithms of the hyperbolic and the Asaoka's method were developed based on outlier detection method. The methods are a successive detection of outliers and a searching method of suitable hyperbolic range for the Asaoka's and the hyperbolic method respectively. Applicability of the algorithms was verified through case studies.