• 대한교통학회지
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• 제17권5호
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• pp.137-149
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• 1999

기존 엇갈림 구간의 속도 및 서비스수준 분석에 관한 연구들은 현장조사를 통하여 엇갈림 구간 주행속도에 영향을 미치는 여러 요소 즉, 구간길이, 차로수, 교통량 등을 독립변수로 하는 회귀식을 도출하였다. 그러나 우리나라의 경우는 엇갈림 구간이 많이 존재하지 않으므로 기존 연구들처럼 현장조사를 통해 회귀식에 필요한 매개변수 값들을 추정하는데 어려움이 있다. 따라서, 엇갈림 구간의 속도추정 및 용량분석을 수행하기 위해 새로운 분석 방법론 개발의 필요성이 대두하게 되었다. 이를 위해 본 연구에서는 엇갈림 구간의 기본적인 특성을 규명하고 이를 수학적 확률식에 의거 엇갈림 구간 주행속도 예측모형을 개발함으로써, 분석대상 엇갈림 구간 수의 부족을 극복하고 범용적으로 적용될 수 있는 방법론을 모색하고자 하였다. 연구는 첫째, 엇갈림 영향권 파악, 둘째, 엇갈림 영향권에서의 차두간격 분포 파악, 셋째, 엇갈림 구간의 최대 가능 엇갈림 교통량 산정, 넷째, 이상적 엇갈림 구간 길이의 산정, 다섯째, 엇갈림 영향권의 속도 예측, 여섯째, 모형의 검증의 여섯 가지 범주로 구분되어 수행되었다. 특히 엇갈림 영향권의 속도 예측은 고속도로 기본구간의 속도와 엇갈림 영향권에서 발생하는 지체시간을 비교하여 결정하였다.

• 대한교통학회지
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• 제10권1호
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• pp.21-40
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• 1992

We examine primarily the existing study procedures for freeway weaving section by comparing speed estimates. Most methods have poor predictions because of neglecting the weaving vehicle influ-ence. In this study we develop the speed prediction equation considering the weaving influence area i.e, weaving box. Assuming that speeds outside weaving box are similar to speeds in freeway basic sec-tions we develop speed equation in box based on the field data. Moreover level of service criteria and weaving analysis precedure are proposed under the new speed prediction equation.

• 한국의류산업학회지
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• 제12권3호
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• pp.272-278
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• 2010

The purpose of this study was to research about Dobby weave design using Computer-Aided Weaving System. For performing this design study, first, it was researched the characteristics of the classified woven fabrics, weaving processing, structure of Dobby loom, and Computer-Aided Dobby Weaving system theoretically. To develop Dobby woven design, Patternland Weave Simulator(U.S.A) for computer weave system was used. Among the developed Dobby woven designs by computer weaving system, mainly three of them were selected and woven into Dobby loom. To see the visual image of the fabric end-use, some of the scanned Dobby fabrics were simulated to the three-dimensional virtual images by Alias CAD system. The result of this study can be summarized as follows. Before the step of weaving Dobby fabrics on the woven design works, Computer-Aided Weaving system can be done very easily to apply the design step of Dobby woven fabrics, specially in case of the complicated woven structure. Also the usage of the simulation CAD system in visual image of the final products, ultimately can be saved cost and developed the higher value-added goods in more response to consumer demands.

• 대한교통학회지
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• 제6권1호
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• pp.17-31
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• 1988

In this research, the behavior of weaving traffic is studied in terms of lane-changing behavior and gap acceptance characteristics. General trends in lane-changing behavior and gap acceptance characteristics are investigated by analyzing descriptive statistics and the factors affecting weaving behavior are determined by means of the multiple linear regression analysis. The results of analysis show that the behavior of weaving traffic is generally similar to that in a basic freeway section and an on- or of- ramp section. Traffic density and speed appear to be better parameters than traffic volume for explaining the behavior of weaving traffic. For the same purpose, using the traffic conditions of the origin and the destination lanes are found to be more effective than using the average traffic conditions of the freeway. A detailed analysis of the gap acceptance characteristics of late merging vehicles shows that there is no significant difference between the size of gaps accepted by late merging vehicles and that accepted by early merging vehicles.

• 한국공작기계학회논문집
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• 제13권3호
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• pp.113-118
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• 2004

In this paper, we propose a new weaving trajectory algorithm for the arc welding of a articulated manipulator. The algorithm uses the theory of Bezier spline. We make a comparison between the conventional algorithms using Catmull-Rom curve and the new algorithms using Bezier spline. The proposed algorithm has been evaluated based on the MATLAB environment in order to illustrate its good performance. Through simulations, the proposed algorithm can result in high-speed and flexible weaving trajectory planning so that it's trajectory cannot penetrate into a base metal compared to the conventional algorithm using Catmull-Rom curve.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1760-1763
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• 2003

In this paper, we propose a new weaving trajectory algorithm for the are welding of a articulated manipulator. The algorithm uses the theory of Bezier spline. We make a comparison between the conventional algorithms using Catmull-Rom curve and the new algorithms rising Bezier spline. The proposed algorithm has been evaluated based on the MATLAB environment in order to illustrate its good performance. The algorithm has been implemented on to the industrial manipulator of DR6 so as to show its real possibility. Through simulations and real implementations, the proposed algorithm can result in high-speed and flexible weaving trajectory planning and can reduce the processing time because it needs one-half calculation compared to the conventional algorithm using Catmull-Rom curve.

• Korean Journal of Mathematics
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• 제7권1호
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• pp.61-69
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• 1999

We determine sparse orthogonal matrices of order $n$ which is fully indecomposable by weaving.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2743-2746
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• 2003

In this paper, we propose a new weaving trajectory algorithm for the arc welding of a articulated manipulator. The algorithm uses the theory of Bezier spline. We make a comparison between the conventional algorithms using Catmull-Rom curve and the new algorithms using Bezier spline. The proposed algorithm has been evaluated based on the MATLAB environment in order to illustrate its good performance. The algorithm has been implemented on to the industrial manipulator of DR6 so as to show its real possibility. Through simulations and real implementations, the proposed algorithm can result in high-speed and flexible weaving trajectory planning and can reduce the processing time because it needs one-half calculation compared to the conventional algorithm using Catmull-Rom curve.

• Journal of Welding and Joining
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• 제15권1호
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• pp.66-80
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• 1997

This paper describes a newly developed arc-sensing algorithm of seam-tracking for FCA W (flux-cored arc welding) horizontal fillet welding. In this algorithm, arc current and the Weighted-Are-Current (WAC) are used to adjust the position of a weld torch in directions of bead throat and weaving, respectively. The WAC, which is newly devised in this study, means that arc current in the vicinity of weaving end is more emphasized than that in the center of weaving. The reason of this is because there usually exists much noise in the center of weaving due to abrupt change of arc length in case some empty gaps exist in a fillet joint Variance analysis was performed in order to check the effect of weld parameters on arc current and the WAC. As a result, the relationships between tip-to-workpiece distance and arc current, and between weaving offset and the WAC were established.To check "the validity of the algorithm, seam-tracking experiments were performed ;mder various welding condition. The result of experiments showed a satisfactory tracking performance in the presence of empty gaps in a horizontal fillet joint.et joint.

• International Journal of Korean Welding Society
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• 제4권1호
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• pp.23-29
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• 2004

In weaving welding where a V groove exists, the heat input distribution is an important factor that determines the defectiveness of the bead shape, undercut and over-lap. In this study, the amount of heat input, which is determined by the welding current, voltage, speed and weaving conditions is calculated through mathematical development and numerical methods. Furthermore, the heat input distribution as a two- dimensional heat source was observed when applied to each groove.