• Journal of the Korean Society of Clothing and Textiles
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• v.8 no.2
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• pp.19-25
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• 1984

The experiment was undertaken to investigate the optimum condition in the effect of seam balance on seam puckering. Four kinds of fabrics were sewed with three kinds of yarns which were used with a seam balance of 90, 100, 110 and $120\%$. In this experiment, the following conclusions were obtained; The best appearance was achieved by a seam balance of $100\~120\%$ in Cotton fabrics, $100\~110\%$ in Rayon fabrics, $110\~120\%$ in Polyester fabrics and $120\%$ in Wool fabrics after laundering.

• Fashion & Textile Research Journal
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• v.4 no.3
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• pp.229-234
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• 2002

An investigation was made of the angle of bias on the lower part of the armhole line of the back bodice and that on the lower part of the sleeve cap curve line by cap heights, and then it was made of the lock stitch seam strength and elongation on the matching angles, the stitch density (26 stitches/3cm, 19 stitches/3cm, 14 stitches/3cm, and the samples (a cotton fabric and two kinds of cotton mixed polyester fabric). The matching angles of the machine-sewed samples are $30^{\circ}/-30^{\circ}$, $30^{\circ}/-45^{\circ}$, $45^{\circ}/-45^{\circ}$ and $60^{\circ}/-60^{\circ}$ by the analysis of the angles of bias on the lower part of the armhole seam. In view of the results of the seam strength and elongation, the reasonable sewing condition of the lower part of the armhole seam was 19 stitches/3cm.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1506-1511
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• 2003

This paper describes an automatic weld seam tracking method of plasma arc welding system designed for the corrugation panel that consists of a linear section and a curved section with various curvatures. Due to the complexity of the panel shape, it is difficult to find a seam and operate a torch manually in the welding process. So, the laser vision sensor for seam tracking is designed for sensing the seam position and controlling a torch automatically. To achieve precise seam tracking, the design of sensor head, image simulation, and calibration are carried out. Through a series of experiment result, compensation algorithm is added and real time error compensation is achieved. The experiment result shows that this vision sensor works effectively. It will provide more precise welding performance and convenience to the operator.

• Transactions of Materials Processing
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• v.9 no.6
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• pp.582-589
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• 2000

In recent automotive industry, vehicle weight can be reduced by one-step forming of tailored blanks welded with two or more sheets of metal blanks. Mash seam welding shows an overlap joint, a much wider welding area, and heat affected zone(HAZ) than a laser welding. This paper deals with the forming characteristics of mash seam welded tailored blanks. Mash seam welded blanks of same or different thickness combinations were prepared, and tensile, hardness, erichsen, and dome stretching tests were done.

• Proceedings of the KWS Conference
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• 1992.04a
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• pp.63-63
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• 1992

본 연구에서는 Zn도금강판의 mash seam용접부의 조직학적 특성 및 도금층 및 인산염 coating의 용접 접합 계면에서의 거동율 검토하여 용접과정율 단계별로 분리 파악하여 계면 파단의 mechanism을 제시하였다. 이와 더불어, mash seam용접부에서 발견 되는 결함의 종류 및 방지대책에 관하여서도 언급하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.10
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• pp.3538-3556
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• 2014

This paper proposes a novel video stitching method that improves real-time performance and visual quality of a multi-camera video surveillance system. A two-stage seam searching algorithm based on enhanced dynamic programming is proposed. It can obtain satisfactory result and achieve better real-time performance than traditional seam-searching methods. The experiments show that the computing time is reduced by 66.4% using the proposed algorithm compared with enhanced dynamic programming, while the seam-searching accuracy is maintained. A real-time local update scheme reduces the deformation effect caused by moving objects passing through the seam, and a seam-based local color transfer model is constructed and applied to achieve smooth transition in the overlapped area, and overcome the traditional pixel blending methods. The effectiveness of the proposed method is proved in the experiements.

• Korean Journal of Computational Design and Engineering
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• v.16 no.5
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• pp.380-389
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• 2011

Esthetic appeal of a product is often affected by the appearance quality of seams forming between components of the product. The appearance quality of seams is, however, assessed in a very subjective and qualitative manner that heavily depends on the evaluator. This paper presents a preliminary study to quantify such assessment by formulating a quantitative index which is a linear function of the seam gap sizes, seam gap ranges, and the size uniformity of seam gaps. By considering a highly simplified problem of a drawer system and utilizing subjective assessments by twenty evaluators, the index has been formulated. The validity of this index has been confirmed by observing its behavior with changes of the component tolerances. Also, the utility of this index has been demonstrated through a selective assembly scheme applied to the drawer system problem. Though the index formulated in this study for seam appearance quality may be useful, future studies are necessary to make the model readily applicable to real problems.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.643-646
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• 2000

In this study, we constructed a preview-sensing visual sensor system for weld seam tracking in real time in GMA welding. A sensor part consists of a CCD camera, a band-pass filter, a diode laser system with a cylindrical lens, and a vision board for inter frame process. We used a commercialized robot system which includes a GMA welding machine. To extract the weld seam we used a inter frame process in vision board from that we could remove the noise due to the spatters and fume in the image. Since the image was very reasonable by using the inter frame process, we could use the simplest way to extract the weld seam from the image, such as first differential and central difference method. Also we used a moving average method to the successive position data of weld seam for reducing the data fluctuation. In experiment the developed robot system with visual sensor could be able to track a most popular weld seam, such as a fillet-joint, a V-groove, and a lap-joint of which weld seam include planar and height directional variation.

• Journal of Broadcast Engineering
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• v.23 no.6
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• pp.896-913
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• 2018

Seam finding algorithm is one of the most important techniques to construct the high quality 360 VR image. We found that some degradations, such as ghost effect, are generated when the conventional seam finding algorithms (for examples, Voronoi algorithm, Dynamic Programming algorithm, Graph Cut algorithm) are applied, because those make the inefficient masks which cross the body of main objects. In this paper, we proposed an advanced seam finding algorithm providing the efficient masks which go through background region, instead of the body of objects. Simulation results show that the proposed algorithm outperforms the conventional techniques in the viewpoint of the quality of the stitched image.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.1
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• pp.9-18
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• 2007

There have been continuous efforts for automation of joint tracking system. This automation process is mainly used to do in root pass of gas metal arc welding in the field of heavy industry and shipbuilding etc. For automation, it is important using of vision sensor. Welding robot with vision sensor is used for weld seam tracking on welding fabrication. Recently, it is used to on post-weld inspection for weld quality evaluation. For real time seam tracking, it is very important role in vision process technique. Vision process is included in filtering and thinning, segmentation processing, feature extraction and recognition. In this paper, it has shown performance comparison results of seam tracking for real time root pass on gas metal arc welding. It can be concluded better segment splitting method than iterative averaging technique in the performance results of seam tracking.