• Structural Monitoring and Maintenance
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• 제4권3호
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• pp.269-299
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• 2017

This paper presents a Level III damage evaluation methodology, which simultaneously, identifies the location, the extent, and the severity of stiffness damage in deep beams. Deep beams are structural elements with relatively high aspect (depth-to-length) ratios whose response are no longer based on the simplified Euler-Bernoulli theory. The proposed methodology is developed on the bases of the force-displacement relations of the Timoshenko beam theory and the concept of invariant stress resultants, which states that the net internal force existing at any cross-section of the beam is not affected by the inflicted damage, provided that the external loadings in the undamaged and damaged beams are identical. Irrespective of the aspect ratios, local changes in both the flexural and the shear stiffnesses of beam-type structures may be detected using the approach presented in this paper.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.926-931
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• 2008

In order to design a high-performance controller with excellent positioning and tracking performance, an optimal tuning method based on the integrated design concept is studied. DOBs, feedforward controllers and CCC are applied to control the bi-axial linear servomechanism. To derive accurate dynamic models of mechanical subsystems equipped with linear servos for the integrated tuning, system identification processes are conducted through the sine sweeping. An optimal tuning problem with stability, robustness and overshoot constraints is formulated as a nonlinear constrained optimization problem. Optimal gains are obtained through the SQP method. Experimental results confirm that both tracking and contouring errors are significantly reduced by applying the proposed controller and integrated tuning method.

• 한국멀티미디어학회논문지
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• 제23권4호
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• pp.603-614
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• 2020

Analyzing various works of Nam June Paik who pioneered the world of video art, we can find a number of audiovisual art pieces - in a broad sense - with the characteristics of "intermedia" that are not clearly identified as one genre. Especially, his career as a musician becomes an important clue for us to discuss the unique originality found in Paik's works. Nevertheless, examples of research that specifically explore how Paik's musicality is reflected in his artistry and could be deeply understood is still rare. This article examines Paik's audiovisual art world, and reviews how his musicality is expressed through the characteristics of media and form, as well as contributed to the ultimate technical and aesthetic realizations of his pieces from the perspective of musical synesthesia. The fact that Paik expanded the concept of music through technology, and fused different media to visualize music, is an important achievement in the context of aesthetic, synesthetic music in the field of audiovisual art.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.350-352
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• 2002

In order to speed up basic concept is to enhance high speed, curve limit speed, cross limit speed, acceleration/deceleration speed. It is important to optimal interface, fundamental technology of vehicle, rail, electrical power, and signal system. Tilting train has advantage minimizing investment cost of infra railway system for increasing train limit speed in curve. the developed tilting train should be operated to commercial service speed 180km/h of 200km/h at KNR upgrade railroad. This paper proposed the basic model of system engineering for developing of tilting EMU(maximum operation speed : 180km/h) with speed-up of conventional railway system.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.855-859
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• 2007

It is essential to obtain accurate and highly reliable streamflow data for water resources planning, evaluation and management as well as design of hydraulic structures. A new discharge estimation method, which is named 'non-dimensional velocity distribution and index-velocity method,' was proposed in this research. This method showed very close channel discharges which were calculated with the exiting velocity-area method. When velocity-area method is used to estimate channel discharge, it is required to observe point velocities at every desired point and vertical using a current meter like Price-AA. However 'non-dimensional velocity distribution and index-velocity method' is used, it become optional to observe point velocities at every desired point and vertical. But this method can not be applied for the cases of very complex and strongly asymmetric channel cross-sections because non-dimensional velocity distribution by entropy concept may be quite biased from that of natural rivers.

• 한국의류학회지
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• 제17권4호
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• pp.602-607
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• 1993

Concept of the comfort and fitness becomes a major concern in the basic function of the ready-made clothes. This research was performed to classify and characterize Korean adult males anthropometrically. Sample size was 1290 subjects and their age range was from 19 to 54 years old. Sampling was carried out by the stratified sampling method. 75 variables in total were applied to classify the bodytypes. Data were analyzed by the multivariate method, especially factor and cluster analysis. The high factor loading items extracted by factor analysis were based to determine the variables of the cluster analysis for the similar bodytypes respectively. In the part of the lower body, 14 variables from the data were applied to classify the bodytypes of lower part by Ward's minimum variance method. The group fanning a cluster were subdivided into 5 sets by cross-tabulation extracted by the hierarchical cluster analysis. Type 3 and 4 in lower body were composed of the majority of 53.1% of the subjects. The Korean adult males had relatively well-balanced in lower body.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.327-334
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• 2001

This paper presents a non-linear analysis procedure for plane frame structures by finite element formulation with assumptions of Timoshenko beam theory. Finite element displacement method based on Lagrangian formulation is used and two-noded and isoparametric line element is adopted to represent finite element model. The layered approach is used for the elasto-plastic analysis of the plane frame structures with rectangular and I cross sections. A load incremental method combined with the tangent stiffness and the initial stiffness methods for each load increment is used for the solution of non-linear equations. Numerical examples are presented to investigate the behavior and the accuracy of the elasto-plastic non-linear application and the results of this study are compared with other solutions using the concept of plastic hinge.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.291-298
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• 2001

When the compression members have the variable cross sections along their member axes, the determination of the elastic critical loads by classical methods becomes impossible and if possible involves complicated calculation only to obtain the approximate values of critical load. In this paper the elastic critical load coefficients of the tapered members with simply supported ends were determined by finite element method. And then the results were represented by simple algebraic equations of two parameters, a( =taper parameter) and m ( = sectional property parameter). One the basis of algebraic equations, the equivalent moment of inertia concept originally proposed by Bleich for a spesific case, are extended to the general cases.

• 전산구조공학
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• 제5권2호
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• pp.119-127
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• 1992

변형영화(strain-softening)현상을 보이는 철근 콘크리트 구조물의 실제 파괴 발생시까지의 거동을 해석하기 위하여 변위제어법을 사용하고, 해석결과의 신뢰도가 떨어지지 않으면서도 해석 수행시간을 줄이기 위하여 기존의 층상화 방법과 비층상화 방법의 장점을 조합한 새로운 기법에 의하여 구조물의 해석을 실시하였다. 또한 선택된 요소의 크기에 따라 해석결과가 다르게 나타나는 현상을 보정해 주기 위한 방법으로 파괴 에너지의 개념을 도입하여 단면의 변형도 분포를 바꾸어 주는 방식을 제안하였으며, 이에 의한 해석을 실시하여 실험치와 비교하였다.

• 대한전기학회논문지
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• 제43권2호
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• pp.329-338
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• 1994

This paper presents a novel method of path planning for a quadruped walking robot on irregular terrain. In the previous study on the path planning problem of mobile robots, it has been usually focused on the collision-free path planning for wheeled robots. The path planning problem of legged roboth, however, has unique aspects from the point of viw that the legged robot can cross over the obstacles and the gait constraint should be considered in the process of planning a path. To resolve this unique problem systematically, a new concept of the artificial intensity field of light is numerically constructed over the configuration space of the robot including the transformed obstacles and a feasible path is sought in the field. Also, the efficiency of the proposed method is shown by various simulation results.