• The korean journal of orthodontics
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• v.15 no.2
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• pp.261-269
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• 1985

The purpose of this study was to measure and compare tensile strength for 3 types of new direct-bond brackets and the same brackets after recycling and to evaluate recycled brackets to determine the extent of physical alteration after recycling. Three types of new direct-bond brackets were bonded to recently extracted human premolar teeth and the tensile strength was measured by Universal Testing Machine. The brackets were recycled by thermal process and the tensile test was repeated. To determine the extent of physical alteration after recycling, the slot width and the hardness of metal brackets were measured and to analyze the microstructure of the brackets, photographs of the bracket microstructure were taken. Following results were obtained: 1. The tensile strength of recycled brackets was lower than that of new brackets, but there was no statistically significant difference. (p>0.05) 2. In the new and recycled brackets, the tensile strength of mini-mesh base bracket was statistically higher than that of conturlok base bracket, $(p\leq0.05)$ but there was no statistically significant difference between production of other companies. (p>0.05) 3. The slot width of metal bracket was enlarged from 0.459mm to 0.469mm as a result of the recycling process. (p>0.005) 4. As temperature was increased in thermal treatment, the grains of bracket metal gradually became coarser and the hardness was decreased.

• Journal of the Semiconductor & Display Technology
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• v.15 no.1
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• pp.27-32
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• 2016

A new lane detection algorithm is proposed for the analysis of DNA fingerprints from a polymerase chain reaction (PCR) gel electrophoresis image. Although several research results have been previously reported, it is still challenging to extract lanes precisely from images having abrupt background brightness difference and bent lanes. We propose an edge based algorithm for calculating the average lane width and lane cycle. Our method adopts sub-pixel algorithm for extracting rising-edges and falling edges precisely and estimates the lane width and cycle by using k-means clustering algorithm. To handle the curved lanes, we partition the gel image into small portions, and track the lane centers in each partitioned image. 32 gel images including 534 lanes are used to evaluate the performance of our method. Experimental results show that our method is robust to images having background difference and bent lanes without any preprocessing.

• Journal of the Korean Society of Costume
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• v.58 no.10
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• pp.65-77
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• 2008

The purpose of this study is to analyze the correlation between the density, the Count and the width of cross section in 2D function through comparison the difference of simulated fabrics based on the various yarns, and to compare the 3D effect by Lay Mapping of diverse fabrics. The method of research is to weave the eight fabrics composed of cotton, linen, worsted, slender yarn, loop, $m{\acute{e}}lange$, woolen, and yarn twist with Hi-Tex program, and to practice 3D mapping with Hi-Print program. As a mapping object, the flared skirt which is a basic costume item is selected. As a result, the thickness of yarn in CAD system was fixed by the width of cross section rather than Count, especially by the width of core section not including the fluff section. The type of yarn such as cotton yarn, linen yarn, and worsted had effect on the shape of texture, but had few interrelations with dimension. In the case of 3D mapping, the textural characteristic and the dimension were presented precisely, whereas there were several limitations. First, the thickness of tissue has not been represented. Secondly, the effect of texture such as fuzzy look, loop was not expressed on the skirt outline including sideline and hemline. Thirdly, the difference of silhouette was not distinct. The common point in 2D and 3D operations is that the representation of texture is relatively accurate and that is difficult to measure and manifest of thickness, the side. For more professional digitalizing in fashion industry, above all in the domain of 3D, it must be supplement the subdivided and differentiated mapping process according to the texture, deviating from the existing analog-based organization which has to designate the form and silhouette suitable for tissue.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.7
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• pp.849-861
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• 1997

In this study, the effect of hole geometry of the cooling system on the flow and temperature field was numerically calculated. The finite volume method was employed to discretize the governing equation based on the non-orthogonal coordinate with non-staggered variable arrangement. The standard k-.epsilon. turbulence model was used and also the predicted results were compared with the experimental data to validate numerical modeling. The predicted results showed good agreement in all cases. To analyze the effect of the discharge coefficient for slots of different length to width, the inlet chamfering and radiusing holes were considered. The discharge coefficient was increased with increment of the chamfering ratio, radiusing ratio and slot length to width and also the effect of radiusing showed better result than chamfering in all cases. In order to analyze the difference between the predicted results with plenum region and without plenum region, the velocity profiles of jet exit region for a various flow conditions were calculated. The normal velocity components of jet exit showed big difference for the low slot length to width and high blowing rate cases. To analyze the flow phenomena injected from a row of inclined holes in a real turbine blade, three dimensional flow and temperature distribution of the region including plenum, hole and cross stream with flow conditions were numerically calculated. The results have shown three-dimensional flow characteristics, such as the development of counter rotating vortices, jetting effect and low momentum region within the hole in addition to counter rotating vortex structure in the cross stream.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.1 s.29
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• pp.49-58
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• 1989

A clothing-erogonomics study was performed to investigate the difference of the upper arm skin skin surface and the relationship among the three aspects of upper arm (height of sleeve rap, sleeve width and armhole girth) by changing arm movements. Plaster cast was used for this experimental research. Arm movements consist of 9 types; just carmly standing on ($0^{\circ}$), and each 4 types ($45^{\circ},\;90^{\circ},\;135^{\circ},\;180^{\circ}$) to the vertical direction in front and in side. The results were as follows; 1) As the arm-movement angle increased, the height of sleeve cap decreased and that ratio was largest in the portion A-B3. 2) The steeve width was enlarged with the increment of movement angle in all portions of upper arm except B1-B5. 3) As increasing the movement angle, the whole armhole girth decreased and the ratio o(front armhole girth (F-A) was larger than that of back. 4) In the vertical direction in front, the height o( the sleeve caps was larger, the sleeve widths were smaller than in the vertical direction in side in all movement types, but there was no significant difference in arm-hole girth between the two cases. 5) There were significantly negative relationships between measurements in height of sleeve cap and those in sleeve width, and also between those in height of sleeve cap and in arm-hole girth. And significantly positive relationships were found between neasurements in height of sleeve cap and those in arm-hole girth.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.2
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• pp.19-28
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• 2018

This study investigated the basic data of architectural design about framework dimensions inherent in a folk house of Yeosu city generally and systematically. We investigated the common dimensions of framework constitution for folk house (main building) seen a lot in Yeosu city. Most of the folk houses in Yeosu city were common people houses built from the end of 19th century to the 1960s and have maintained the same style for a long time. As a result of the study, common dimensions were calculated in two ways. One is Front toi/3ryang house and the other is Front/back toi/2kozu5ryang house. Front/back toi house was large in the case of full width, total height, and member thickness but, width of the front kan is no big difference. In other words, the scale of Front toi house and Front/back toi house is difference only in the rest except front kan (width). Among calculated common dimensions, the front kan of Front toi house and Front/back toi house in the plan, the kitchen is the widest, and the size is the same at 8.7 chucks degree. The next became small little by little in order of room 1(main room), room 2(center room), room 3(end room). As a result, the size of the room 3 of Front toi house reaches 7.7 chucks, and room 3 of Front/back toi house reaches 8.0 chucks. In the section dimensions, pillar height is in sum of floor height and pillar core height, Front toi house is 7.9 chucks, and Front/back toi house is 8.2 chucks. The investigation of basic data of architectural design is not only makes possible to grasp specific and simple to three-dimensional universal aspect on framework dimensions, but also documentation of folk house design know-how is done, and the architectural design standards of Korean folk house is written in the contents according to the area.

• Fashion & Textile Research Journal
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• v.8 no.5
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• pp.552-561
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• 2006

This study was conducted to suggest an appropriate jacket bodice pattern for elderly women by comparing the developed pattern with existing ready-made jacket pattern. The developed jacket bodice pattern was produced from the basic sloper in which elderly women's somatotype was fully reflected, by using the newly developed 3D pattern design system. Subjects were 6 elderly women aged from 60 to 69 who have average somatotype in their age group. This study carried out pattern analysis and self-sensory test with three ready-made jackets(national brands) and suggested a developed jacket pattern based on the results. According to the self sensory test results of ready-made jacket, wearing fitness among brands was significantly different even though those brands were same B91 size. The results of ready-made jackets' pattern analysis, size differences among patterns have influenced wearing fitness. The basic numerical formula for the jacket pattern considered elderly women's somatotype were as follows; $B/4+2{\pm}0.2{\sim}0.5$(difference of front and back), $W/4+2{\pm}0.2{\sim}0.5$(difference of front and back), H/4+2~7(ease amount), armhole depth B/4, chest width B/6+1, back width B/6+3 and back neck width B/12+0.5. According to the results of the developed jacket's appearance evaluation, it earned higher scores in silhouette and ease amount, confirming that the developed jacket is appropriate for the elderly women. Also, in the evaluation on space length, the developed jacket pattern was evaluated to allow proper space length in all around of measurement parts.

• Journal of Advanced Marine Engineering and Technology
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• v.18 no.1
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• pp.114-122
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• 1994

A cold temperature control system for the BAF(batch annealing furnace) has been established in order to reduce energy consumption to imrpove productivity and stabilize the properties of products. Therefore we confirmed a relation between annealing cycle time and atmospheric gas, changing annealing cycle time according to BAF temperature with time during heating and actual temperature measurements cold spot during soaking. The results of the temperature variation effect on the batch annealing are as follows. 1) Cooling rate is increasing gradually with increasing atmospheric gas flow, but heating rate is hardly increasing without atmospheric gas component. Heating time is reduced to one half with increasing atmospheric gas flow rate and changing of atmospheric gas component from HNx to Ax gas and annealing cycle time is reduce to 2.7 times. 2) With enlarging the difference between furnace temperature and soaking temperature at the HNx BAF, heating time becomes short, but cooling time is indifferent. 3) If temperature difference of 300.deg. C in the temperature change of cold spot according to the annealing cycle control temperature, Hi-CON/H2BAF is interchanging at each other at 26hours, but HNxBAF at 50 hours. 4) Soaking time at batch annealing cycle determination is made a decision by the input coil width, and soaking time for quality homogenization of 1219 mm width coil must be 2.5 hours longer then that of 914mm width coil for the same coil weight at Hi-CON/H2BAF. But, it is necessary to make 2 hours longer at HNxBAF.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.6
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• pp.57-63
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• 2000

A multi-branch thermo-optic switch has a problem that driving powers in the switching states are different from each other; the power consumption for the inner output port is more than twice as large as that form the outer output port. In this pater, to solve this problem unequal width heaters and the waveguide structure with a thin overcladding layer are proposed in a four-branch thermo-optic switch. The proposed structure is fabricated with the polymer materials with high index difference, Teflon and polyimides. The fabricated device was measured at the wavelength of 1550 nm. The measured characteristics exhibit the smaller difference in the power consumption between the switching states and the driving power les than the previous four-branch thermo-optic switch with equal width heaters. As for the device performance, the crosstalk is better than - 16 dB at about 310 ~ 390 mW, the insertion loss is 4.7 dB, and the switching time is less than 1 ms.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.7
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• pp.1675-1683
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• 1995

A numerical study of the fluid flow and heat transfer characteristics of the two-dimensional impingement jet with a confinement plate has been carried out. The fluid flow was calculated by solving the full Navier-Stokes equation. In doing that, the well known SIMPLER algorithm was used and the trouble making convection term was discretized according to QUICKER scheme. The energy equation was simply solved by using the SOR method. For the Reynolds number of 10000, two channel heights, say 1.5 and 3.0 times the jet exit width, and two thermal boundary conditions constant wall temperature and constant wall heat flux were considered. Discrete heat sources were flush mounted along the impingement plate at a distance of 0, 2, 3, 4, 5, 6, 10, 12, times the jet exit width from the stagnation point. The length of each heat source is 4 times the jet exit width long. The Nusselt number averaged over each heat source was compared with experiment. Comparison shows that both calculations and experiment have the secondary peak of Nusselt number at downstream of stagnation point, even though there is a little quantitative difference in between. The difference is believed due to abscure thermal boundary condition in experiment and also accuracy of turbulence model used. The secondary peak is shown to be caused by rigorous turbulent flow motion generated as the wall jet flow is retarded and developes into the channel flow without flow reversal.