• 제목/요약/키워드: Top-Down Movement

검색결과 39건 처리시간 0.019초

도심지 지하굴착에 적용된 Top-Down 공법의 수치해석과 실측비교 (Top-Down Method of Deep Basement Construction in Urban Area : a Comparison of Numerical Analysis and Field observation Data)

  • 김학문
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1991년도 추계학술발표회 논문집 지반공학에서의 컴퓨터 활용 COMPUTER UTILIZATION IN GEOTECHNICAL ENGINEERING
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    • pp.312-331
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    • 1991
  • 런던시내의 역사적 건물들 주변에서 LONDON CLAY층을 굴착하고 지하 5층의 주차장 건설에 TOP-DOWN공법이 적용되었다. 인접 구조물들의 안전진단을 수치해석(F.E.M)으로 예측하고 현장에서 실측한 자료와 비교분석하였다. 사용된 탄소성 COMPUTER 모델은 현장계측값들과 비교적 잘 일치하고 있으며, 지하 연속벽(DIAPHRAGM WALL)을 이용한 TOP-DOWN공법이 주변지반 변형을 감소시킬 수 있는 가장 효과적인 방법으로 판명되었다.

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Three Effective Top-Down Clustering Algorithms for Location Database Systems

  • Lee, Kwang-Jo;Yang, Sung-Bong
    • Journal of Computing Science and Engineering
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    • 제4권2호
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    • pp.173-187
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    • 2010
  • Recent technological advances in mobile communication systems have made explosive growth in the number of mobile device users worldwide. One of the most important issues in designing a mobile computing system is location management of users. The hierarchical systems had been proposed to solve the scalability problem in location management. The scalability problem occurs when there are too many users for a mobile system to handle, as the system is likely to react slow or even get down due to late updates of the location databases. In this paper, we propose a top-down clustering algorithm for hierarchical location database systems in a wireless network. A hierarchical location database system employs a tree structure. The proposed algorithm uses a top-down approach and utilizes the number of visits to each cell made by the users along with the movement information between a pair of adjacent cells. We then present a modified algorithm by incorporating the exhaustive method when there remain a few levels of the tree to be processed. We also propose a capacity constraint top-down clustering algorithm for more realistic environments where a database has a capacity limit. By the capacity of a database we mean the maximum number of mobile device users in the cells that can be handled by the database. This algorithm reduces a number of databases used for the system and improves the update performance. The experimental results show that the proposed, top-down, modified top-down, and capacity constraint top-down clustering algorithms reduce the update cost by 17.0%, 18.0%, 24.1%, the update time by about 43.0%, 39.0%, 42.3%, respectively. The capacity constraint algorithm reduces the average number of databases used for the system by 23.9% over other algorithms.

중국의 '과학보급' 정책과 '과학화운동'

  • 한성구
    • 중국학논총
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    • 제67호
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    • pp.101-121
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    • 2020
  • 中国近代以来一直由国家主导推进科学普及运动。 甚至把普及科学知识当作建设富强社会主义国家的重要手段, 致力于科学化运动。 本论文将通过中国的科学普及政策和科学化运动的开展过程, 了解科学在中国如何在理念上实现最大化。 另外, 在大众科学的形成过程中, 将探索国家是如何定义和利用科学的, 在科学知识的生产和形成过程中, 大众的地位和作用如何。 为此, 首先将了解新中国国家政策和法规中反映的科学普及运动的内容, 以既是这些政策的理论,思想源流, 又是民国时期中国'科学化运动'堡垒的杂志《科学中国》为中心, 了解中国近代科学普及运动的性质和发展情况。

Top Down 공사의 선기둥 수직도 계측 (Measurement of Prefounded Column Erection During Top Down Construction)

  • 임홍철;신천균;김승원
    • 한국건축시공학회지
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    • 제6권4호
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    • pp.77-83
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    • 2006
  • The purpose of this study is to measure the straightness of prefounded columns during underground construction stages. There are several causes of an error of prefounded column: (1) columns connected by welding or bolting, (2) by placement of concrete and aggregates around columns, (3) movement during construction, and (4) load applied during construction. The error of column straightness is different for each column, and the tilting of columns is shown in one or two directions between floors. The additional loads caused by the error of straightness may give damage to buildings. This paper presents the measurement results of column straightness, and thus providing a basis for further analysis.

Measured structural response of a long irregular pit constructed using a top-down method

  • Yang, Sun;Yufei, Che;Zhenxue, Gu;Ruicai, Wang;Yawen, Fan
    • Geomechanics and Engineering
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    • 제31권5호
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    • pp.489-503
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    • 2022
  • A 1257-m-long irregular deep foundation pit located in the central of Nanjing, China was constructed using the combined full-width and half-width top-down method. Based on the long-term field monitoring data, this study analyzed the evolution characteristics of the vertical movement of the columns, internal force of the struts, and axial force of the structural beam and slab. The relevance of the three mentioned above and their relationship with the excavation process, structural system, and geological conditions were also investigated. The results showed that the column uplift was within the range of 0.08% to 0.22% of the excavation depth, and the embedded depth ratio of the diaphragm wall and the bottom heave affected significantly on the column uplift. The differential settlement between the column and diaphragm wall remained unchanged after the base slab was cast. The final settlement of the diaphragm wall was twice the column uplift. The internal force of the struts did not varied monotonically but was related to numerous factors such as the excavation depth, number of struts, and environmental conditions. Additionally, the dynamic force and deformation of the columns, beams, and slabs were analyzed to investigate the inherent relationship and variation patterns of the responses of different parts of the structure.

유도 공중회전낙법의 COG변인 분석 (A COG Variable Analysis of Air-rolling-breakfall in Judo)

  • 김의환;정재욱;김성섭
    • 한국운동역학회지
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    • 제15권3호
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    • pp.117-132
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    • 2005
  • It was to study a following research of "A Kinematic Analysis of Air-rolling-breakfall in Judo". The purpose of this study was to analyze the Center of Gravity(COG) variables when performing Air-rolling-breakfall motion, while passing forward over(PFO) to the vertical-hurdles(2m height, take off board 1m height) in judo. Subjects were four males of Y. University squad, who were trainees of the demonstration exhibition team, representatives of national level judoists and were filmed by four 5-VHS 16mm video cameras(60field/sec.) through the three dimensional film analysis methods.COG variable were anterior-posterior directional COG and linear velocity of COG, vertical directional COG and linear velocity of COG. The data collections of this study were digitized by KWON3D program computed The data were standardized using cubic spline interpolation based by calculating the mean values and the standard deviation calculated for each variables. When performing the Air-rolling-breakfall, from the data analysis and discussions, the conclusions were as follows : 1. Anterior-posterior directional COG(APD-COG) when performing Air-rolling-breakfall motion, while PFO over to the vertical-hurdles(2m height) in judo. The range of APD-COG by forward was $0.31{\sim}0.41m$ in take-off position(event 1), $1.20{\sim}1.33m$ in the air-top position(event 2), $2.12{\sim}2.30m$ in the touch-down position(event 3), gradually and $2.14{\sim}2.32m$ in safety breakfall position(event 4), respectively. 2 The linear velocity of APD-COG was $1.03{\sim}2.14m/sec$. in take-off position(event 1), $1.97{\sim}2.22m/sec$. gradually in the air-top position(event 2), $1.05{\sim}1.32m/sec$. in the touch-down position (event 3), gradual decrease and $0.91{\sim}1.23m/sec$. in the safety breakfall position(event 4), respectively. 3. The vertical directional COG(VD-COG) when performing Air-rolling-breakfall motion, while PFO to the vertical-hurdles(2m height) in judo. The range of VD-COG toward upward from mat was $1.35{\sim}1.46m$ in take-off position(event 1), the highest $2.07{\sim}2.23m$ in the air-top position(event 2), and after rapid decrease $0.3{\sim}0.58m$ in the touch-down position(event 3), gradual decrease $0.22{\sim}0.50m$ in safety breakfall position(event 4), respectively. 4. The linear velocity of VlJ.COG was $1.60{\sim}1.87m/sec$. in take-off position(event 1), $0.03{\sim}0.08m/sec$. gradually in the air-top position(event 2), $-4.37{\sim}\;-4.76m/sec$. gradual decrease in the touch-down position(event 3), gradual decrease and -4.40${\sim}\;-4.77m/sec$. in safety breakfall position(event 4), respectively. When performing Air-rolling-breakfall showed parabolic movement from take-off position to air-top position, and after showed vertical fall movement from air-top position to safety breakfall. In conclusion, Ukemi(breakfall) is safety fall method Therefore, actions need for performing safety fall movement, that decrease and minimize shock and impact during Air-rolling-breakfall from take-off board action to air-top position must be maximize of angular momentum, and after must be minimize in touch-down position and safety breakfall position.

THE THEORETICAL AND SITE BEHAVIOUR OF A BRACED DIAPHRAGM WALL-A COMPARISON

  • Kim, Hak-Moon
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1990년도 PROCEEDINGS OF THE FIRST KOREA-JAPAN JOINT GEOTECHNICAL SEMINAR ON EXCAVATION and TUNNELING IN URBAN AREAS
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    • pp.111-128
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    • 1990
  • Three numerical analysis carried out for the design of a diaphragm wall were examined by the results of field observation data. Utilizing the wall stiffness, supporting system and construction sequence, the relative merits of those factors on the analysis of diaphragm wall have been investigated and their effects are compared tilth the observed behaviour of the wall. The predicted bending moment and wall displacement by elasto-plastic method agreed well with the observed values. The rigid slab supported system (i.e Top-Down Method) found to be the most effective way of controlling ground movement.

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아마추어골퍼들의 스윙 오류에 관한 연구 (A Study of Golf Swing Errors of Amateur Golfer)

  • 임정;전철우;정재욱
    • 한국운동역학회지
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    • 제16권2호
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    • pp.165-174
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    • 2006
  • The purpose of this study was to review the relevant literature about coaching and thereupon, survey the coaching methods used for golfer lesson to reinterpret them and thereby, describe in view of kinetics the swing errors committed frequently by amateur golfers and suggest more scientific golfer coaching methods. For this purpose, kinetic elements were divided into precision and power ones and therewith, the variables affecting such elements were identified. On the other hand, swings were divided into address, take-back, back-swing, back-swing top, down-swing, impact and follow-through to determine 20 variables for each form and thereby, define their errors to determine the relations between their frequency and errors. For this study, a total of 60 amateur golfer were sampled, and their swing forms were photographed with two high-speed digital cameras, and the resultant images were analyzed to determine the errors of each form kinetically, which would be analyzed again with the program V1-5000. The results of this study can be summarized as follows; The kinetic elements could be identified as precision, power and precise power. Thus, setup and trajectory were classified into precision elements, while differences of inter-joint angles, cocking and delayed hitting. Lastly, timing and axial movement were classified into precise power elements. Three errors were identified in association with setup. The errors related with trajectory elements accounted for most (7) of the 20 errors. Three errors were determined for inter-joint angle differences, and one error was associated with cocking and delayed hitting. Lastly, one error was classified into timing error, while five errors were associated with axial movement. Finally, as a result of arranging the errors into a cross table, it was found that the errors were associated with each other between take-back and back-swing, take-back and follow-through, back-swing and back-swing top, and between back-swing and down-swing. Namely, an error would lead to other error repeatedly. So, it is more effective to identify all the errors for every form and correct them comprehensively rather than single out the errors and correct them one by one.

시선추적 분석을 위한 통합 해석 모델의 개발 - 사용자 인터페이스 디자인을 위한 휴리스틱 가이드라인의 도출을 중심으로 - (Development of Integrated Analysis Model for Eyegaze Analysis - With Emphasis on the Generation of Heuristic Guidelines for User Interface Design -)

  • 성기원;이건표
    • 디자인학연구
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    • 제17권2호
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    • pp.23-32
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    • 2004
  • 본 연구는 사용자의 시지각 프로세스에 대한 분석을 통해 시선추적 과정을 이해하고, 인간의 정보처리 모델을 기반으로 휴리스틱 가이드라인을 도출하여, 실무에서 적용할 수 있는 인터페이스 디자인의 일반적인 원리를 발견하는 것에 목적이 있다. 이를 위해 인간의 시각 특성을 이용한 시선추적 시스템을 실험에 적용하여, 상향처리와 하향처리의 시지각 프로세스를 파악하고 인간의 정보처리 모델을 근거로 디자인을 위한 적용점을 분석하였다. 사례 연구로 인터랙티브 미디어를 실험하여 시선의 동선 및 고정점을 통해 사용자의 관심을 확인하고, 사용자의 인지과정을 이해하기 위한 단서를 효과적으로 얻을 수 있었다 그리고, 인간 행위의 각 단계와 정보처리 모델을 기반으로 다섯 가지의 휴리스틱 가이드라인을 도출하였으며, 이를 통하여 디자인 실무에서 직접 적용할 수 있는 인터페이스 디자인의 일반적인 원칙을 발견할 수 있었다.

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북미지역 공동체 아카이브의 '거버넌스' 논의와 비판적 독해 (A Study of the Governance Discussion on Community Archives in North America)

  • 이경래
    • 기록학연구
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    • 제38호
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    • pp.225-264
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    • 2013
  • 이 글은 미국과 캐나다의 북미 국가들에서 활발하게 진행되고 있는 '참여 아카이브(participatory archives)'를 중심으로 한 공동체 아카이브의 '거버넌스' 논의를 분석하고, 이로부터 국내 공동체 아카이브의 발전에 긍정적 함의를 도출하는 데 목적이 있다. 이 글은 북미에서의 공동체 아카이브에 대한 주요 특징들, 즉 추진 주체로서 주류 문화기관, 수집기관 중심의 아카이브 정리 및 기술, 그리고, 평가 주체로서 아키비스트의 역할론을 제시함으로써, 이들 국가들이 역사적으로 관 주도형 하향식 모델을 지배적 아카이브 시스템으로 채택하고 있음을 재차 확인한다. 이 때문에 하향식 모델의 한계점을 극복하기 위한 방안으로 민 관의 협치에 기반하여 아카이빙 전 과정에 공동체 참여를 적극적으로 독려하는, 북미 국가들이 최근 시도하고 있는 참여 아카이브의 제안을 살핀다. 결론에서는, 북미 거버넌스 논의의 비판적 독해를 통해 한국적 함의를 살핀다. 즉 국가기록원을 비롯해 다양한 주류 문화기관들이 추진 주체가 되어 구축해 왔던 대부분의 공동체 아카이브가 여전히 관주도의 '공동체에 관한(about the community)' 기록에 머물러 있는 우리 상황에서, 북미 참여 아카이브에서 보여지는 타자화된 공동체 기억을 복원하려는 논의는 국내 공동체 아카이브가 재활력을 얻는 데 중요한 시사점을 준다고 판단한다.