• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 추계 학술논문 발표대회
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• pp.81-85
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• 2009

In the recent years, the high strength concrete has increasingly been used according to extending market of tall buildings. However, Ministry of Land, transport and Maritime Affairs was established by law with an alternative plan after June 2008 because of the weakness of high strength concrete accompanied spalling phenomena in fire. The mix design of concrete has to properly meet standards which are the spalling resistance of concrete and limited temperature of steel reinforcement. The fire proof concrete mixed fiber has widely been used to meet spalling safety on the many construction sites, the most researches about the fire proof concrete mixed fiber had being carried out focused on fire resistance, compressive strength and cast in place of concrete. But the most important thing is column shortening used the fire proof concrete within the vertical members. In this paper, the fire proof concrete filled spalling safety standards was experimented by required material when the column shortening is revised between normal concrete and fire proof concrete mixed fiber and then the results have done a comparative analysis. Also, The paper aimed to indicate a basic data for revision of column shortening of fire proof concrete.

• 로봇학회논문지
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• 제12권1호
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• pp.78-85
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• 2017

This paper presents the development of a 3D printer based piezo-driven vertical micro-positioning stage. The stage consists of two flexure bridge structures which amplify and transfer the horizontal motion of the piezo-element into vertical motion of the end-effector. The stage is fabricated with ABS material using a precision 3D printer. This enables a one-body design eliminating the need for assembly, and significantly increases the freedom in design while shortening fabrication time. The design of the stage was optimized using response surface analysis method. Experimental results are presented which demonstrate 100nm stepping in the vertical out-of-plane direction. The results demonstrate the future possibilities of applying 3D printers and ABS material in fabricating linear driven motion stages.

• Geomechanics and Engineering
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• 제13권6호
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• pp.963-975
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• 2017

Improvement of soft clay deposit by preloading with vertical drains is one of the most popular techniques followed worldwide. These drains accelerate the rate of consolidation by shortening the drainage path. Although the analytical and numerical solutions available are mostly based on equal strain hypothesis, the adoption of free strain analysis is more realistic because of the flexible nature of the imposed surcharge loading, especially for the embankment loading used for transport infrastructure. In this paper, a numerical model has been developed based on free strain hypothesis for understanding the behaviour of soft ground improvement by vertical drain with preloading. The unit cell analogy is used and the effect of smear has been incorporated. The model has been validated by comparing with available field test results and thereafter, a hypothetical case study is done using the available field data for soft clay deposit existing in the eastern part of Australia and important conclusions are drawn therefrom.

• 한국정밀공학회지
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• 제13권11호
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• pp.132-142
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• 1996

This paper presents a technique to model and control a manipulator which has a flexible link and moves in a vertical plane. The flexible link is modeled as an Euler-Bernoulli Beam. Elastic deformation of the flexible link is represented using the assumed modes method. A comparison function which satisfies all geometric and natural boundary conditions of a cantilever beam with an end mass is used as an assumed mode shape. Lagrange's equation is utilized for the development of a discretized model. This paper presents a simple technique to improve the correctness of the developed model. The final model including the shortening effect due to elastic deformation correlates very well with experimental results. The free body motion simulation shows that two assumed modes for the representation of the elastic deformation is proper in terms of the model size and correctness. A control algorithm is developed using PID control technique. The proportional, integral and derivative control gains are determined based on dominant pole placement method with a rigid one-link manipulator. A position control simulation shows that the control algorithm can be used to control the position and residual oscillation of the flexible one-link manipulator effectively.

• 한국전산구조공학회논문집
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• 제23권4호
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• pp.395-401
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• 2010

시간이 지남에 따라 건물의 수직부재가 수축하는 것을 기둥축소라고 한다. 건물의 고층화 및 비정형화 추세 때문에 수직부재들에 작용하는 축하중 크기 간의 차이를 피할 수 없게 되며, 이의 영향으로 인접 수직부재 간의 축방향 축소량이 차이가 나게 된다. 이러한 부등축소량은 수직부재와 수평부재의 접합부에 추가적인 응력을 유발시키거나 슬래브의 기울어짐 또는 간벽이나 창호 등 비구조재의 사용성에 문제를 초래하게 된다. 이러한 부등축소량의 영향을 감소시키기 위하여 시공 중 수직부재의 설치 시 예측된 보정을 하게 된다. 보정의 합리성은 각 부재별 축소량의 정확한 예측과 예측된 축소량을 이용한 각 부재들의 합리적 보정량 산정에 있다. 부등축소량의 예측은 점점 더 정확해지고 있으나 보정 기법에 관한 연구는 거의 없다. 따라서 본 논문에서는 이동 평균법을 사용한 보정 기법과 보정하면서 발생하는 오차에 대한 합리적인 제한조건을 제시하였으며, 제한조건의 변화와 보정 그룹 수의 관계를 살펴봄으로써 제한조건 설정의 객관적인 판단 기준이 되었다. 그리고 이전에 연구되어진 SA 알고리즘을 사용한 최적 보정 기법과 결과를 비교해 봄으로써 이동 평균법 보정 기법의 효과를 검증하였다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제19권4호
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• pp.47-60
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• 2013

Purpose: This study examines construction core plans for the users of vertical-typed general hospitals to effectivly use the flow line. Methods: The study sampled representative 9 hospitals, calculated the depth value through Convex Map of Space Syntax and Justified Graph according to the determination of form of construction cire, and analyzed its functional connectivity. Results: The analysis of the connectivity between operation core part and emergency part of core space with high importance in the hospitals showed that the types of hospital and hospital have the lowest depth value in the spatial phase diagram, where central treatment part and outpatient part are arranged well vertically. Elevators for patients at these hospitals are close to operation and emergency parts actually separated from the elevators for passengers. For shortening of flow line of patients and private movement environment, however, it is desirable to arrange the elevators for patients to be adjacent to the operation parts and to arrange the emergent patient entrances more effectively to separate them from the flow line of visitors and guardians. Implications: Consideration should be taken into account for the effective flow line design. This study hopefully may serve as a stepping stone for the standard design of horizontal/vertical flow line.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.404-407
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• 2004

The construction of high-rise buildings is increased. The Vertical Member of tall buildings is inherently shortened and it causes several seriously problems such as tilting of slab, crack within partition wall, deformation of curtain wall. This also affects structural stability by inducing unexpected stress to the structural members such as outrigger. In this study, the column shortening according to revised field information and to compare the analysis results the actual field measurement. Pusan The $\#$, a 51-story apartment building which is currently under construction was chosen for the case study.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.465-469
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• 2006

In recent years there has been considerable interest in the construction of super high-rise buildings. From the prior art, various procedures and devices for surveys during and after the phase of erection of a high-rise building are known. High-rise buildings are subject to strong external tilt effects caused, for instance, by wind pressures, unilateral thermal effects by exposure to sunlight, and unilateral loads. Such effects are a particular challenge in the phase of construction of a high-rise building, in as much as the high-rise building under construction is also subject to tilt effects, and will at least temporarily lose its - as a rule exactly vertical - alignment. Yet construction should progress in such a way that the building is aligned as planned, and particularly so in the vertical, when returning into an un-tilted basic state.It is essential that a straight element be constructed that theoretically, even when moving around its design centre point due to varying loads, would have an exactly vertical alignment when all biasing conditions are neutralised. Because of differential raft settlement, differential concrete shortening, and construction tolerances, this ideal situation will rarely be achieved. This paper describes a procedure developed by the authors using GPS observations combined with a network of precision inclination sensor to provide reliable coordinated points at the top of the worldwide highest-rise building under construction in Dubai.

• 대한기계학회논문집
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• 제16권6호
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• pp.1075-1088
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• 1992

본 연구에서는 두개의 팔을 가지는 실험용 로보트를 모델링 하기위해 사용된 기법들을 제시한다. 로보트는 수직 평면상에서 움직이므로 중력의 영향을 받는다. 그리고 두팔은 모두 탄성을 가진다. 이 로보트는 탄성 멤버들을 가지는 로보트의 여 러 제어기법들을 연구하기위해 만들어졌다. 시스템의 특성들은 아주 유연한 멤버들 을 가지게끔 정해진다.이것은 제어를 위해 쓰이는 전자부품들에 요구되는 밴드폭을 제안하고, 탄성이 크고 빠른 로보트에서 관찰 되어지는 유연한 운동들을 흉내낸다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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• pp.91-94
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• 2006

The way to shorten a construction period is considered to an very important technology development element as reducing the formwork removal periods with promoting strength revelation own concrete. This study executed experiment to review usability of early strength revelation chemical admixture which is judged in ways effective with premature removal of form about concrete. Use of early strength revelation AE water reducin admixture is apperaing so that strength revelation by early hydration promotions is excellent. The results of being applied proposed work process are that compressive strength are appeared more than 5MPa within 16 hours so that removal of vertical form was possible. the concrete compressive strength satisfied with a more than 2/3 of specified concrete strength for removal of horizontal form are appeared in 42 hours of 27 MPa proportioning strength, in 36 hours of 30, 35 MPa proportioning strength so that the 6 days cycle time of concrete structural frame work is cut by 2 days as shortening delayed period in works of removing slab forms. So construction cost reductions and a construction period shortening are judged so that it is possible.