• Journal of Electrical Engineering and information Science
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• 제2권6호
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• pp.177-182
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• 1997

A visual servoing method is proposed for a robot with a camera in hand. Specifically, vanishing point features are suggested by employing a viewing model of perspective projection to calculate the relative rolling, pitching and yawing angles between the object and the camera. To compensate dynamic characteristics of the robot, desired feature trajectories for the learning of visually guided line-of-sight robot motion are obtained by measuring features by the camera in hand not in the entire workspace, but on a single linear path along which the robot moves under the control of a commercially provided function of linear motion. And then, control actions of the camera are approximately found by fuzzy-neural networks to follow such desired feature trajectories. To show the validity of proposed algorithm, some experimental results are illustrated, where a four axis SCARA robot with a B/W CCD camera is used.

• Coupled systems mechanics
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• 제2권4호
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• pp.389-410
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• 2013

Three-dimensional Lagrangian fluid finite element is applied to seismic response analysis of an oil storage tank with a floating roof. The fluid element utilized in the present analysis is formulated based on the displacement finite element method considering only volumetric elasticity and its element stiffness matrix is derived by using one-point integration method in order to avoid volumetric locking. The method usually adds a rotational penalty stiffness to satisfy the irrotational condition for fluid motion and modifies element mass matrices through the projected mass method to suppress spurious hourglass-mode appeared in compensation for one-point integration. In the fluid element utilized in the present paper, a small hourglass stiffness is employed. The fluid and structure domains for the objective oil storage tank are modeled by eight-node solid elements and four-node shell elements, respectively, and the transient response of the floating roof structure or the free surface are evaluated by implicit direct time integration method. The results of seismic response analyses are compared with those by other method and the validation of the present analysis using three-dimensional Lagrangian fluid finite elements is shown.

• 응용통계연구
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• 제35권1호
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• pp.63-75
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• 2022

본 논문은 Wang과 Samworth (2018)가 제안한 성근 프로젝션 방법을 개선하여 MOSUM을 이용하여 고차원의 시계열데이터에 존재하는 다중 평균 변화점을 추정하는 방법에 대해서 제안한다. 제안한 방법은 국소방법으로 다중 변화점을 동시에 찾을 수 있어 순차적 오류를 최소화 할 뿐만 아니라 평균이 상쇄되는 경우에도 변화점을 추정하는 장점을 지니고 있다. 또한 데이터 의존적인 방법으로 블록 와일드 붓스트랩 방법을 활용하여 임계점을 찾는 방법을 제안한다. 모의 실험을 통해 제안한 방법이 좋은 성능을 보임을 확인하였으며 S&P 500 지수를 구성하는 개별 기업들의 금융 자료에 적용하여 최근 6년간 네 번의 변화점을 찾았다.

• 비파괴검사학회지
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• 제25권1호
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• pp.1-8
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• 2005

본 연구에서는 TV 유리패널의 등색프린지 분포를 광탄성 4단계 위상이동법에 의하여 측정한 실험결과를 제시하였다. 재래식 광탄성법에서는 등색 프린지 차수를 각각의 점에 대해서 수작업으로 측정한다. 4단계 위상이동법을 이용하기 위하여, 원형편광기 요소들은 등색프린지분포가 측정되는 지점 혹은 선상을 따라 등경각 방향에 일치시켜야 한다. 4단계 위상이동법은 원형편광기의 검광판을 $0^{\circ},\;45^{\circ},\;90^{\circ}$ 및 $135^{\circ}$ 회전시켜 얻은 4개의 영상을 이용한다. 4단계 위상이동법을 적용하기 위해서는 등경각이 측정하고자 하는 지점이나 선상에 일치하도록 편광기 요소를 정렬시켜야 한다. 4단계 위상이동법으로부터 얻은 실험결과는 세나르몽보간법에 의해 측정한 값과 비교한 결과 서로 잘 일치하였다. 또한, TV 유리패널의 열처리 전 후에 등색프린지 분포를 비교하였다. 측정 결과, TV 유리패널의 열처리 전 후의 등색프린지 차수는 약 2배정도 차이가 나타났다.

• 소성∙가공
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• 제11권3호
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• pp.231-237
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• 2002

The manufacturing of a metal bellows consists of the four main forming processes; deep-drawing, ironing, tube bulging and folding. Among these, the bulging and folding processes are critically important because the quality of metal bellows is greatly influenced by the forming conditions of these processes. In the present study, the finite element analysis technique is applied to the bulging and folding processes. The springback analysis is also called out. From the analysis results, it has been revealed that around the crown point the stress state is in one-directional tension and one-directional bending mode. Meanwhile, around the inner point of metal bellows it is in two-directional bending mode. It has also revealed that the thickness of metal bellows around the crown point is nearly uniform.

• 전자공학회논문지A
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• 제33A권5호
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• pp.44-54
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• 1996

Various types of B-ISDN bearer connection can take place according to access types of endpoint equipments in call and number of connectio between endpoints. In this paper, performance of application signalling protocol on three basic facilities of B-ISDN CS-2 signalling system, such as connection of point-to-point, point-to-multipoint and multiconnection call, is evaluated and compared. For performacne evaluation, experimental model of B-ISDN application signalling protocol is implemented and respective message processing time of each process is measured. By applying message processing time to local exchange system, cal processing capacity of application signalling protocol on three basic connection types is evaluated by simulation method. In this paper, local exchange system is considered to have two ATM NNI links and four ATM UNI links.

• Structural Engineering and Mechanics
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• 제18권2호
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• pp.195-209
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• 2004

By means of the two-dimensional basic equations of transversely isotropic magneto-electro-elastic media and the strict differential operator theorem, the general solution in the case of distinct eigenvalues is derived, in which all mechanical, electric and magnetic quantities are expressed in four harmonic displacement functions. Based on this general solution in the case of distinct eigenvalues, a series of problems is solved by the trial-and-error method, including magneto-electro-elastic rectangular beam under uniform tension, electric displacement and magnetic induction, pure shearing and pure bending, cantilever beam with point force, point charge or point current at free end, and cantilever beam subjected to uniformly distributed loads. Analytical solutions to various problems are obtained.

• 대한간호학회지
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• 제38권1호
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• pp.111-121
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• 2008

Purpose: The purpose of this study was to analyze attitudes toward a successful life of students majoring in nursing science. Method: The Q-methodology which provides a method of analyzing the subjectivity of each items was used. The 32 selected Q-statements from each of 36 subjects were classified into a shape of normal distribution using a 9 point scale. The collected data was analyzed using a QUANL PC program. Result: Four types of successful life attitudes for research subjects in nursing science were identified. Type I is purpose achievement type, Type II is calling fullness type, Type III is balance maintenance type, and Type IV is happiness eagerness type. Conclusion: The results of the study indicate that different approaches to nursing professional education programs are recommended based on the four types of successful life attitudes.

• 한국의상디자인학회지
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• 제3권2호
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• pp.87-106
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• 2001

This study is to measure and evaluate the sensibility image for textile color and pattern design of woman's golfwear. Four-group colors and four patterns classified by a pracical survey on the market are presented. A questionnaire has 14 sensibility related words scaled by 7 point semantic differential method. The practical research is performed for 150 women screened by sensibility test for individual preference analysis based on the ages. Each subject is answered by a face-to-face interview method to improve survey's accuracy. For statistical results there are significant differences in treatment means of sensibility measurements according to the ages. Sensibility image for textile color and pattern design is significantly different according to individual character based on ages. In summary, this paper has proposed the sensibility image scale for textile color and pattern design of women's golfwears to satisfy individual sensibility according to ages. The results of this study can be effectively applied to develop textile color and pattern design based on human sensibility.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.639-642
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• 1999

There exist geometrically invariant relations in single-view images under a specific geometrical structure. This invariance may be utilized for 3D object recognition. Two types of invariants are compared in terms of the robustness to the variation of the feature points. Deviation of the invariant relations are measured by adding random noise to the feature point location. Zhu’s invariant requires six points on adjacent planes having two sets of four coplanar points, whereas the Kaist method requires four coplanar points and two non-coplanar points. Experimental results show that the latter method has the advantage in choosing feature points while suffering from weak robustness to the noise.