• International Journal of Precision Engineering and Manufacturing
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• 제1권1호
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• pp.118-126
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• 2000

Die-casting burr to casting process is removed by post-process for assembly and quality control of product. Though robot has been widely used for deburring job before. CNC exclusive machine is currently developed for high power, high speed machining and quick tool change. Deburring tool path with complex 3D curve type is defined to make out deburring NC program. But there is no efficient method to define it currently used methods with teaching probe on machine. In this study the efficient method to make out deburring NC program is developed. 5-axis digitizing machine is used to receive data of deburring path. And the post process for NC program generation is developed in consideration of the machining conditions. The developed system is not dependent on the skill of operator and has the advantage to maintain the flexibility of job to modify NC program due to the wear of tool and aging of the die casting.

• 전자공학회논문지S
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• 제34S권11호
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• pp.1-8
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• 1997

A prediction model is proposed to describe the path loss in propagation environment of indoor microcell. This model includes the lineal corridor for line--of-sight(LOS) and T-shaped corridor for non-line-of-sight(NLOS). In computation of receiving power the ray tracing technique based on image method is utilized and also reflected waves bounced on the walls and ceilings are considered. To check validity of the computed resuls cross checks between the predicted and measured are being made, which shows a close agreement for LOS case whereas somewhat disagreement for NLOS case. UTD technique is incorporated with propagation path determination algorithm in the treatment of NLOS case.

• 한국정밀공학회지
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• 제17권1호
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• pp.93-100
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• 2000

Die-casting burr due to casting process is removed by post-process for assembly and quality control of product. Though robot has been widely used for deburring job before, CNC exclusive machine is currently developed f3r high power, high speed machining and quick tool change. Deburring tool path with complex 3D curve type is defined to make out deburring NC program. But there is no efficient method to define it currently used methods with teaching probe on machine. In this study the efficient method to make out deburring NC program is developed. 5-axis digitizing machine is used to receive data of deburring path. And the post processor for NC program generation is developed in consideration of the machining conditions. The developed system is not dependent on the skill of operator and has the advantage to maintain the flexibility of job to modify NC program due to the wear of tool and aging of the die casting.

• 한국정밀공학회지
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• 제13권9호
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• pp.62-69
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• 1996

Interpolator is a very important element in NC machines in that it controls tool path and speed. In this paper, studied were extensive interpolation characteristics of reference pulse method among various interpolation and pulse generation methods. Specifically, processing speed and path error of DDA, SPD and SFG methods were compared and analyzed against line, circle and elipse. As a result, in the point of processing speed, SPD method was found to be the best for line interpolation, SFG method for circle and ellipse, and DDA method was found to be the slowest for all paths. In the point of path error, DDA method was found to have the biggest error for all kinds of paths.

• 로봇학회논문지
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• 제5권1호
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• pp.41-47
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• 2010

This paper proposes a path planning method of a mobile robot in two-dimensional work space. The path planning method is based on a cell decomposition approach. To create a path which consists of a number of line segments, the Delaunay Triangulation algorithm is used. Using the cells produced by the Delaunay Triangulation algorithm, a mesh generation algorithm connects the starting position to the goal position. Dijkstra algorithm is used to find the shortest distance path. Greedy algorithm optimizes the path by deleting the path segments which detours without collision with obstacles.

• 건축역사연구
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• 제25권3호
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• pp.63-70
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• 2016

This paper aimed to identify a main-path remains in the Hwangnyongsa temple site based on studying published the excavation survey report and researching relics related to the path in the ancient temple site. Hwngnyongsa temple, there were three type's paved footway, straight path to the central axis line of the layout, outside path around the main buildings and the front square of the lecture hall. These remains were expected that installed for some purposes, such as marches, touring, sort of a Buddhist ceremony been performed at the time of Silla. Straight path shows there were two rows of the main access inside the roofed corridor. A row consisted of the 2~3 pieces processed stone(Jangdaeseok) altogether with 92cm width and combined with square stone and stepping stone on the end of the road. It is regarded as very characteristic form and one of the architectural elements of Hwangnyongsa temple in Unified Silla period.

• 제어로봇시스템학회논문지
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• 제12권7호
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• pp.671-678
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• 2006

This article proposes a smooth path generation and time scheduling method for general tasks defined by non-smooth path segments in industrial robotic applications. This method utilizes a simple 3rd order polynomial function for smooth interpolation between non-smooth path segments, so that entire task can effectively maintain constant line speed of operation. A predictor-corrector type numerical mapping technique, which correlates time based speed profile to the smoothed path in Cartesian space, is also provided. Finally simulation results show the feasibility of the proposed algorithm.

• 대한산업공학회지
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• 제22권3호
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• pp.499-515
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• 1996

The basic function of on industrial robot system is to move objects in the workspace fast and accurately. One difficulty in performing this function is that the path of robot should be programmed to avoid the collision with obstacles, that is, tools, or facilities. This path planning requires much off-line programming time. In this study, a SOM technique to find the collision-free path of robot in real time is developed. That is, the collision-free map is obtained through SOM learning and a collision-free path is found using the map in real time during the robot operation. A learning procedure to obtain the map and an algorithm to find a short path using the map is developed and simulated. Finally, a path smoothing method to stabilize the motion of robot is suggested.

• 한국지리정보학회지
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• 제7권2호
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• pp.16-28
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• 2004

영상 모자이크 작업에서 두 영상 간의 경계선이 보이지 않는 최적의 seam-line을 구하기 위해 화소값 차이 변환과 동적계획법 이용 알고리즘을 제안하였다. 영상 간의 경계선은 두 영상의 화소값 차이가 적은 화소를 따라 형성되는 것이 시각적 부담이 적다. 이 화소들을 연결하는 것은 최적 경로를 찾는 알고리즘을 이용할 수 있다. 최적 경로 결정에 효과적인 동적계획법을 seam-line 결정에 직접 적용하변 화소값의 차이뿐만 아니라, seam-line의 길이에 따라 영향을 받는 거리영향문제가 발생한다. 이 논문에서는 적응적 변환함수를 사용하여 비용 변환을 수행하고, 변환된 비용공간 상에서 동적계획법을 적용하여 거리영향이 억제된 최적 seam-line을 구할 수 있는 알고리즘을 개발하였다. 또한 결정된 seam-line을 평가하기 위해 일정한 개수의 상위 화소값의 차이를 누적한 값(SFBPD)을 척도로 제시하였다. 제안한 seam-line 결정방법을 다양한 종류의 영상에 대해 적용 실험하였으며, 시각적 및 SBPD 값에 의한 수치적 결과를 제시하였다.

• The Journal of Korean Physical Therapy
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• 제26권6호
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• pp.459-463
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• 2014

Purpose: The purpose of this study was to investigate the correlations between functional movement screen (FMS) and ankle dysfunctions in subjects with chronic ankle instability (CAI). Methods: This study was a cross-sectional study of 20 participants with CAI. The ankle dorsiflexion range of motion (ROM), Foot and Ankle Disability Index (FADI), center of pressure (COP) path length, and COP velocity for ankle dysfunction were measured in all the subjects. All the subjects underwent the FMS concerned with ankle functions consisted of deep squats, hurdle steps and in-line lunges. The Spearman rank-order correlation coefficient was used to determine relationship between the ankle ROM, FADI, COP and FMS. Results: The results of the deep squat and in-line lunge exercises revealed a significant correlation with the ankle dorsiflexion ROM, FADI, COP path length, and COP velocity. The hurdle step showed no correlation with the ankle dorsiflexion ROM and FADI but a significant relationship with the COP path length and COP velocity. Conclusion: The results of this study showed that relationship deep squat and in-line lunge and it is suggested that an assessment tool using ankle dorsiflexion ROM and ankle instability would be clinically effective.