• Journal of Welding and Joining
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• v.14 no.6
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• pp.131-139
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• 1996

The response of the arc sensor using the welding current and/or welding voltage as its outputs has been obtained by the analysis and/or experiments of the static characteristics of arc sensor. But in order to improve the reliability of arc sensor, it is necessary to know its dynamic characteristics. So in this paper, it is presented the dynamic model of arc sensor including the power source, arc voltage, electrode burnoff rate, and wire feed rate. A numerical simulation of the dynamic model of arc sensor was implemented, computing the welding current with input of CTWD. The results of computer simulations and experiments of $CO_2$arc welding showed that a linear relationship between weaving center - weld line distance and current area difference was established. Additionally, a real-time weld seam tracking system interfaced with industrial welding robot was constructed, the result of the weld seam tracking experiment for weld line with an initial offset error of 5$^{\circ}$was good.

• Journal of the Korean Society of Costume
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• v.59 no.3
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• pp.131-144
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• 2009

This study is about single-layered $Chog{\breve{a}}ri$ excavated from SongHyosang(宋效商, 1430-1490, SHS hereafter), SongHeeJong(宋喜從, the late 1500s, SHJ hereafter) tombs. There are 7 single-layered $Chog{\breve{a}}ris$ for men. We focus on comparison of their design and sowing method. 1. Design: Investigating collar, $Chog{\breve{a}}ris$ from SHS have MokpanGit and $Chog{\breve{a}}ris$ from SHJ have KalGit. KalGit has been seen from SHJ to 17th, 18th and 19th centuries. After the late 1500s, there is no MokpanGit single-laTered $Chog{\breve{a}}ri$ for men. Side panel under arm has various shapes(triangle, trapezoid, triangle+trapezoid) in 15th century. After the late 1500s, It changes into no side panel. Two $Chog{\breve{a}}ris$ with no side panel from SHJ reveals that the late 1500s is a period of transition. 2. Sewing method: First, researching lengthwise grainline of the fly, the left fly has lengthwise grainline outside In four, inside in three. The right fly has lengthwise grainline outside in just one, the others have lengthwise grainline inside. Compared with today's way, there is a great difference, but in those times there isn't an established rule. This is true of side panel under arm. The sewing method are backstitch, running stitch, and hemming. Researching the construction method of seam, in putting two selvages together, open seam and plain seam are used. In putting selvage and bias, bias and bias together, flat felled seam and french seam are used. This study shows that single-layered $Chog{\breve{a}}ri$ far men from 15C. to 16C. has changes of design such as collar(Git) and side panel undo. arm. But there is little change in sewing method.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.1
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• pp.147-164
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• 2022

The aim of this study was to reproduce the ordinary attire of Yi Seung-hyu, a civil official and writer of the late Goryeo, which will be used to make a his portrait. The reproduced costume consists of a single-layered pyoui (表衣) and jungdan (中單), lined jeogori and baji, and geon (巾), created with reference to historical documents, materials, and portraits. The pyoui was made with samcheokbe, with an H-shaped neck-shoulder band, an oblique single collar, and rectangular gussets. Two skirts were attached on the inside at the back, similarly to dopo. The jungdan also has an oblique single collar, but has an I-shaped neck-shoulder band and triangular gussets. A flat felled seam stitch, whip stitch, and French seam stitch were used in the hemlines and seams of the pyoui and jungdan. The jeogori and baji were made with toju (土紬), and small ties were attached to stabilize them. The geon is a long, oblique hat, which has folded side lines, and was made with flexible black hangra and using a French seam stitch and backstitch. The results include the elements of "restoration, historical research, and portrait costume", and will be maintained as the cultural heritage of Samcheok City.

• Journal of Welding and Joining
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• v.18 no.5
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• pp.49-54
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• 2000

High speed rotating arc process, forming a flat bead surface with shallow penetration depth, can be applied to the automatic seam tracking, because the amplitude of current waveform increases at high rotation speed. Two high speed arc rotation mechanisms have been developed in Japan and Germany b rotating the electrode nozzle using an external motor, which are used prevalently for narrow gap and conventional seam welding. In this study, a new rotation mechanism was developed by using a hallow shaft motor designed to be installed in the electrode nozzle. By rotating the welding arc, the amplitude of current waveform increases remarkably since the self-regulation of arc is not fully performed. Experiments show that the arc sensor with high-speed rotation arc has improved its responsiveness and sensitivity.

• The Research Journal of the Costume Culture
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• v.18 no.5
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• pp.892-907
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• 2010

The purpose of this study was to compare torso pattern made by draping and flat pattern method in terms of the size of breast. The size of this study was classified as 75A and 75D according to the size of breast. Each torso pattern by the combination of the size and pattern method was compared and analyzed. In order to test the fit of the draping and flat pattern that was developed according to the size of breast, the outer appearance was evaluated. The results of the study were as follows: First, The most striking size difference was difference between the front and the back on bust line level, which decides on position of the side seam in comparison of size between draping and flat pattern of 75A and 75D. In the flat pattern, the difference between the front and the back in the size of breast was consistent regardless of a change in the size of breast. However, in the draping, the bigger breast led to the bigger difference between the front and the back on bustline level. Second, the flat pattern in 75D was evaluated to be the worst in 27 items among total 46 items for the evaluation of outer appearance in the draping and flat pattern of 75A and 75D. Third, regardless of size, the draping was evaluated to be more suitable in the areas related to neck, arm hole, and waist dart than the flat pattern. These results are suggesting that the draping is a method of reflecting characteristic of the body type more accurately than the flat pattern, and that the draping is a more suitable method than the flat pattern for the design of clothing pattern of the body type with big breast like 75D.

• Journal of the Korean Society of Costume
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• v.57 no.3 s.112
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• pp.14-22
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• 2007

This study is about the excavated costume representing fundamental "Conservation and Restoration". It's not a report of a specific case, but it is a guideline that contains the costume and textile of museum collection. It is not research based on experiments; however, this paper is basically consists of various reported-documents. Followings are the conclusions of this study 1. These are the factors that we have to know to prevent the causes of fabric's degradation. -Light, -Humidity and temperature, -Microscopic organism, -Insect and rodent animal, -Air pollution, -Ph, -Handling 2. Basic principles of conservation and restoration follows are: -Select the Reversible method, -Represent the easily distinguishable repaired place, -Should be acted by an expert or people with experience, -Before the restoration, accurate and specified records should be completed, -Procedure, treatment method, and materials used should be recorded prior to restoration, -Should be cared minimally, -Be cautious when using the conservation materials, -When caring, make sure nothing is against the principle of aesthetic, historic, and form of preservation 3. The types of restoration are type of straight or curve, type of hole, type of without warp or weft, type of special part damage something like sleeve, collar, type of form that is severely damaged, and type of separated pieces. 4. The method of restoration is sewing, stitching, and the combination of sewing and stitching. 5. The restoration seams are welt seam, plain seam, flat felled seam, french seam etc. And there are kinds of used-sewing, such as, broad stitching, backstitch, half backstitch, basking, hemming, saddle stitching etc.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.2
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• pp.218-222
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• 2014

In this paper, we introduce an autonomous calibration method for a 2D laser displacement sensor (e.g. laser vision sensor and laser range finder) by matching a single point on a flat structure. Many arc welding robots install a 2D laser displacement sensor to expand their application by recognizing their environment (e.g. base metal and seam). In such systems, sensing data should be transformed to the robot's coordinates, and the geometric relation (i.e. rotation and translation) between the robot's coordinates and sensor coordinates should be known for the transformation. Calibration means the inference process of geometric relation between the sensor and robot. Generally, the matching of more than 3 points is required to infer the geometric relation. However, we introduce a novel method to calibrate using only 1 point matching and use a specific flat structure (i.e. circular hole) which enables us to find the geometric relation with a single point matching. We make the rotation component of the calibration results as a constant to use only a single point by moving a robot to a specific pose. The flat structure can be installed easily in a manufacturing site, because the structure does not have a volume (i.e. almost 2D structure). The calibration process is fully autonomous and does not need any manual operation. A robot which installed the sensor moves to the specific pose by sensing features of the circular hole such as length of chord and center position of the chord. We show the precision of the proposed method by performing repetitive experiments in various situations. Furthermore, we applied the result of the proposed method to sensor based seam tracking with a robot, and report the difference of the robot's TCP (Tool Center Point) trajectory. This experiment shows that the proposed method ensures precision.

• The Research Journal of the Costume Culture
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• v.6 no.2
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• pp.127-140
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• 1998

A study on the construction of Dan-Ryung in the early 16th century based on the shrouds from excavated tomb of Kim, Heum-Jo(1461-1528) is reported in this paper. This study is aimed at establishing database for a traditional Korean costume construction and emphasizing the necessity for development of methodology in writing report from excavated costume including measuring, construction methods and materials. This paper includes examples of measured length for each part of 'Dan-Ryung', reconstructured drawings, pictures, and construction methods. The followings on the construction of Dan-Ryung in the early 16th century are found in this study: 1) Dan-Ryung robes were made of less expensive hemp, cotton, silk & cotton, and ramie & silk. 2) As a whole, Dan-Ryung was lengthy and spacious and it had straighter and narrower sleeves when compared to the ones from the late Chosun. 3) There existed Moo which was large rectangular guest with double pleats at Dan-Ryung's side seam. Its round collar was constructed with a 3 cm width bias. Ball buttons on the outer collar and loops on the right shoulder are attached. 4) There existed a pair of indirectly attached slim and short strings. Inside string is directly attached. 5) Inside of the shoulder, a U-shaped shoulder pad made of the same cloth as the inner cloth was attached. hand sewing methods used include delicate flat-felled seam stitch, back-stitch and sew-up stitch.

• Laser Solutions
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• v.12 no.3
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• pp.14-17
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• 2009

The laser welding was performed for the flange joint of two overlapped coaxial circular pipes which serve as the inlet and connector pipes of STS 316L. The laser welding test finally resulted in a good penetration depth of 1.8 to 2.0 mm. On the way to get the good welding quality, two important parameters were found to be optimized. One is the focal positioning which is the offset of the laser beam focus to the exact welding seam line, which is more critical in the inner flange laser welding. When the beam spot size was deviated more than $200\;{\mu}m$ from the seam line, welding of two pipes is failed. The other is a gap size since a certain amount of gap is inevitable due to fabrication tolerance, or artificial allowances for smooth insertion of a pipe. However, it is required to restrict the gap allowance within 0.2mm to avoid undesirable undercut on a welding bead.

• Journal of the Korean Home Economics Association
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• v.46 no.9
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• pp.137-146
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• 2008

This study was conducted in order to spread out lower body 3D scan data of men in their twenties. The aim was to achieve slacks pattern with ease allowance through comparison with existing flat patterns. For conversion of 3D scan data into 20 pattern, reference lines were established by using Rapid Foam in 3D shape analysis software. 2C-AN program and Yuka CAD were used to convert 20 pattern earned with straight posture of 3D scan data into slacks pattern by using Triangle Simplification & Runge-Kutta Method. In order to achieve this we needed to set a line 9cm below the hip line, to array vertex of each block to crease line while maintaining the horizontal line. And then we needed to set ease allowance in back crotch and to set waist circumference or hip circumference ease allowance in side seam of slacks. Results showed that long front crotch length can be achieved if 3D scan data is compared with 20 existing flat pattern. Slacks pattern that raise front crotch by about 1.5cm compared to back crotch and also possess ease allowance in back crotch area are great in appearance evaluation.