• 한국생산제조학회지
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• 제25권6호
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• pp.504-510
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• 2016

Robots are widely utilized in many fields, and various demands need customized robots. This study proposes an optimal design method based on swarm intelligence for selecting the kinematic parameter of a manipulator according to the task space trajectory desired by the user. The optimal design method is dealt with herein as an optimization problem. This study is based on swarm intelligence-based optimization algorithms (i.e., ant colony optimization (ACO) and particle swarm optimization algorithms) to determine the optimal kinematic parameters of the manipulator. The former is used to select the optimal kinematic parameter values, whereas the latter is utilized to solve the inverse kinematic problem when the ACO determines the parameter values. This study solves a design problem with the PUMA 560 when the desired task space trajectory is given and discusses its results in the simulation part to verify the performance of the proposed design.

• The Journal of Korean Physical Therapy
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• 제23권2호
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• pp.7-15
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• 2011

Purpose: We investigated the relationship between the muscle activity and kinematic variables of the upper extremity during a push-up task on stable and unstable surfaces. Methods: We recruited 15 healthy subjects. Subjects completed the push-up task on stable and unstable surfaces. Surface electromyograms were recorded from the serratus anterior, upper trapezius, latissimus dorsi, infraspinatus to monitor changes in muscle activity. Markers for kinematic changes of elbow flexion, shoulder extension, shoulder retraction and scapular adduction were attached at C7, the T7 spinous process, both acromions, the scapula superior and inferior angle, the humerus lateral epicondyle, and the ulnar styloid process. Correlation coefficients between muscle activity and kinematic variables were analyzed by SPSS for Windows, version 15.0. Results: On the unstable surface, elbow flexion and shoulder extension increased with increasing muscle activity of serratus anterior, upper trapezius and infraspinatus. On the stable surface, shoulder retraction decreased with increasing muscle activity of serratus anterior and infraspinatus. Scapular adduction decreased with all types of increasing muscle activity, regardless of the support surface. Conclusion: Correlations between muscle activity and kinematic variables were observed on stable and unstable surfaces during a push-up task, while correlations between right and left variables were not clear. These finding suggest that it may be used to develop a rehabilitation program which could be effective in improving shoulder function in patients with shoulder problems.

• Structural Engineering and Mechanics
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• 제54권4호
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• pp.793-807
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• 2015

Constructing the influence lines of forces of statically indeterminate structures is a traditional issue in structural engineering and mechanics. However, the existing kinematic method for establishing these force influence lines is an indirect or mixed approach by combining the force method with the theorem of reciprocal displacements, which is yet inconsistent with the kinematic method for statically determinate structure. This paper proposes the direct kinematic method in conjunction with the load-displacement differential relation for exactly constructing influence lines of reaction and internal forces of indeterminate structures. Firstly, through applying the principle of virtual displacement, the formula for influence lines of reaction and internal forces of indeterminate structure via direct kinematic method is derived based on the released structure. Then, a computational approach with a clear concept and unified procedure as well as wide applicability based on the load-displacement differential relation of beam is suggested to achieve conveniently the closed-form expression of force influence lines, and exactly draw them. Finally, three representative examples for constructing force influence lines of statically indeterminate beams and frame illustrate the superiority of the proposed method.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권3호
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• pp.652-669
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• 2014

This paper concerns the kinematic characteristics of a coupling device in a deep-seabed mining system. This coupling device connects the buffer system and the flexible pipe. The motion of the buffer system, flexible pipe and mining robot are affected by the coupling device. So the coupling device should be considered as a major factor when this device is designed. Therefore, we find a stable kinematic device, and apply it to the design coupling device through this study. The kinematic characteristics of the coupling device are analyzed by multi-body dynamics simulation method, and finite element method. The dynamic analysis model was built in the commercial software DAFUL. The Fluid Structure Interaction (FSI) method is applied to build the deep-seabed environment. Hydrodynamic force and moment are applied in the dynamic model for the FSI method. The loads and deformation of flexible pipe are estimated for analysis results of the kinematic characteristics.

• 로봇학회논문지
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• 제10권2호
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• pp.119-132
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• 2015

Two novel parallel mechanisms (PMs) employing two or three PaPaRR subchains are suggested. Each of those two PMs has translational 3-DOF motion and employs only revolute joints such that they could be adequate for haptic devices requiring minimal frictions. The position analyses of those two PMs are conducted. The mobility analysis, the kinematic modeling, and singularity analysis of each of two PMs are performed employing the screw theory. Then through optimal kinematic design, each of two PMs has excellent kinematic characteristics as well as useful workspace size adequate for haptic applications. In particular, by applying an additional redundantly actuated joint to the 2-PaPaRR type PM which has a closed-form position solution, it is shown that all of its parallel singularities within reachable workspace are completely removed and that its kinematic characteristics are improved.

• 한국측량학회지
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• 제16권1호
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• pp.27-40
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• 1998

본 논문은 구조물의 변형과 거동의 모니터링에 GPS 측위기술의 적용가능성을 제시한다. 첫번째 부분은 GPS관측의 반복재현성(repeatability)에 대한 정량적 연구로서 기준망내 기준점들간의 기선벡터를 반복적으로 측정함에 있어서 동일한 결과가 얻어질 수 있는가를 구명하고자 하였으며, 두번째 부분은 한 점당 몇 분이내의 관측시간이 소요되는 kinematic GPS측량의 변형 모니터링 수행성을 평가하고자 하였다. 흙댐을 대상으로 계절 및 수위정도에 따라 총 4차에 걸쳐 모니터링 시험망에 대한 관측을 수행하였다. 기준망은 static 방식으로 관측하였고, 모니터링 점들에 대해서는 kinematic방식은 물론 static 및 rapid-static방식으로 각각 관측을 행하여 종래의 측량기법으로 얻어진 결과와 비교하였다. 기준점들간의 기선벡터 관측에서 평균 7 mm 이내의 3차원 기선벡터의 반복재현성을 성취할 수 있었으며, 기준망들의 폐합오차는 4∼27 ppm를 나타내었다. kinematic 접근법은 종래의 측량기법에 비하여 기준점들과 모니터링 점들간의 경사거리에서 34 m의 차를 나타내었고, 높이에서는 4∼8 mm의 차를 나타내었다. kinematic GPS 측량기법은 5 m정도의 측정능력을 지닌 종래의 측량기법에 의한 변형 모니터링의 효율적인 대안이 될 수 있음을 확인할 수 있었다.

• 한국CDE학회논문집
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• 제15권3호
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• pp.212-221
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• 2010

Proposed in the paper is a methodology to generate kinematic template for 3D JIG models. Recently, according to increase of the rate of automatic facility in manufacturing system, the 3D manufacturing and verification research and development have been issued. So, unlike in the past, moving 3D facilities are very various like JIGs, turn table, AS/RS worked in the automated manufacturing industry. Because 3D mesh models are used in these kinds of 3D simulation, users have to define the kinematic information manually. This 3D mesh data doesn't have parametric information and design history of the 3D model unlike the design level data. So, it is lighter than 3D design level data and more efficient to render on the 3D virtual manufacturing environment. But, when user wants to find a common axis located between the links, the parameter information of the model has to reconstruct for defining kinematic construction. It takes a long time and very repetitive to define an axis and makes a joint using 3D mesh data and it is non-intuitive task for user. This paper proposed template model that provides kinematic information of the JIG. This model is kinds of a state diagram to describe a relation between links. So, this model can be used for a kinematic template to the JIG which has a same mechanism. The template model has to be registered in the template library to use in the future, after user made the model of the specific type of the 3D JIG model.

• 대한공간정보학회지
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• 제13권1호
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• pp.63-69
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• 2005

InSAR(Interferometric Synthetic Aperture Radar)는 급속히 발진하고 있는 기술이며 지표면의 수치지형모델 제작과 토지이용 분류뿐만 아니라, 지진, 화신, 지반침하와 빙하흐름의 모니터링과 같은 다양한 응용분야 적용은 그것의 장점을 강화시켜 주고 있다. InSAR는 원격탐측 기술의 한 부류이므로, 위성위치와 자세, 대기, 그리고 기타 요소에 의한 다양한 오차원인을 가지고 있으므로, 이 시스템의 정확도 검증, 특별히 SAR 영상으로부터 제작된 수치지형모델에 대해서는 중요하다. 본 연구에서는 RTK GPS와 Kinematic GPS 측위가 InSAR 기술로 제작된 수치지형모델의검증 도구로 이용되었다. 그 결과로서, Kinematic GPS는 실험지역에서 RTK GPS보다 많은 관측값을 얻을 수 있었지만, 안테나 주위 나무 등에 의한 위성추적 문제와 통신거리에 따른 기준국과 이동국사이의 자료전송 문제 등이 여전히 시급히 해결해야 할 과제로 나타났다.

• 한국운동역학회지
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• 제27권1호
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• pp.9-18
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• 2017

Objective: The purpose of this study was to identify kinematic variables that govern successful performance and judges' scores and to establish correlative relationships among those of Yurchenko layout with a full twist in female vaults. Method: Four video cameras with sampling rate of 60 Hz collected 32 motion data of Yurchenko vaults from twenty-two female participants (age: $18.6{\pm}3.6years$, height: $153.0{\pm}6.5cm$, mass: $44.7{\pm}7.3kg$) during national competition. Posting processing and calculations of kinematic variables were performed in Kwon 3D XP and $Matlab^{(R)}$ programs. Correlation and regression analyses were applied to find the relationships between the obtained scores and kinematic variables. Deterministic model (Hay & Reid, 1988) was used to investigate the strength of correlative relationships among kinematic variables. Results: The obtained scores from the judges' decision were mainly affected by post-flight peak height, horse contact time, knee angle at landing, and horse takeoff angle. Strong blocking during horse contact was required to get successful performance and obtain high scores. Modified deterministic model showed that round-off entrance and takeoff angles and resultant velocity of the center of mass (CM) during the roundoff phase were the starting variables affecting performance in the following kinematics. Knee angle at landing, a highly influential variable on the obtained point, was only determined by judges' decision without significant correlative relationship with previous kinematic variables. Conclusion: The obtained scores highly depended on kinematic variables of post-flight and horse contact phases that were affected by those from the previous phases including round-off postures and resultant velocity of the body center of mass.

• Spatial Information Research
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• 제9권2호
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• pp.309-324
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• 2001

본 연구에서는 실시간 동적 GPS 측량의 응용을 위해 우선 전국에 분포된 상시관측점들의 공경기준계 성과를 도출하고, 후처리에 의한 연속 동적 GPS 방법과 실시간 동적 GPS 방법을 적용하여 육상과 해상지역에 대한 지형 해석을 시도하였다. 실시간 동적 GPS 측량을 위한 초기 조건과 관측 시간대를 고려한 다음, 후처리에 의한 연속 동적 GPS 측량과 실시간 동적 GPS 측량을 수행하였으며, 본 연구를 의해 실시간으로 GPS 관측자료를 저장할 수 있는 프로그램을 개발하여 결과값을 동시에 저장하고 controller를 통해 관측 당시의 위성 상태를 모니터링 할 수 있는 시스템을 제안하였다. 실시간으로 관측된 GPS관측값의 위치 정확도는 후처리에 의한 정확도와 같은 정도로 획득할 수 있었으며, 항만의 매립, 준설공사나 하천에서의 유사량 변화 탐지등에 매우 높은 정확도로 수치지형모형을 구축할 수 있었고, 해안 지형의 특성해석에 유용하게 응용될 것으로 기대된다.