• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.1 s.160
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• pp.68-76
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• 2007

The purpose of this study is to investigate change of mechanical and physical properties, shape behavior and hand value in weft knit when rib stitch and milan stitch are combined. The knit stitches used in this study are plain stitch, half milan rib stitch, milan rib stitch, $2{\times}1$ rib stitch, $2{\times}1$ half milan rib stitch and $2{\times}1$ milan rib stitch. We analyzed physical and mechanical properties(tensile, bending, shear, compression, surface properties, thickness and weight) of the knit stitches and calculated their primary hand value and total hand value through translational formulas using the KES(Kawabata Evaluation System). The results are as follows; In evaluation of mechanical properties and hand values of knit stitches, plain stitch had the highest flexibility and the lowest T.H.V. as women's winter knit wear. Since $2{\times}1$ rib stitch had too high elongation in one direction, although it had the highest T.H.V, it needs to be careful when plain stitch and $2{\times}1$ rib stitch are applied for women's winter knit wear. Since Milan rib stitch and $2{\times}1$ milan rib stitch had high T.H.V. similarly, it is considered that they are suitable for women's winter knit wear. Specially, when Milan stitch is combined with $2{\times}1$ rib stitch, its shape stability and fullness are contained and flexibility is added on it. Therefore, $2{\times}1$ milan rib stitch can be also applied for women's winter knit wear.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.2 s.38
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• pp.199-209
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• 1991

In this paper, the fabrics for Korean folk clothes(KFC) undergoes repeated laundering under given condition. After this cyclic laundering was applied, the mechanical properties of the specimen were measured using KES-F system in order to evaluated the end-use performance of fabrics for KFC. And also, the crease recovery of fabrics for KFC were measured by shirley crease recovery tester. 78 different kinds of commercial silk fabrics and polyester fabrics for KFC were used for this study. The experimental results were analysed statistically to relate the mechanical properties and the crease recovery of fabrics for KFC. Furthermore, these changes in dimensional stability, mechanical properties and handle of fabrics for KFC were discussed in comparison with those values for silk fabrics and polyester fabrics. The results obtained are as follows. 1. Regardless of materials, remarkable increase are observed in shrinkage of the fabrics for KFC about repeated laundering, but dull increase are observed in shrinkage after 10 cycles of the repeated laundering. On the other hand, slack extend are observed in dimensions after 20 cycles of the repeated laundering. The shrinkage of fabrics for KFC after 10 cycles of the lundering showed that the silk fabrics are $1.74{\pm}0.33\%$ (warp direction) and $1.35{\pm}0.23\%$ (weft direction) and the polyester fabrics are $1.45{\pm}0.22\%$ (warp direction) and $1.25{\pm}0.23\%$ (weft direction). 2. Except for tensile property, these changes in mechanical properties of fabrics for KFC by laundering have $\pm$ 16 range of bending, shearing, compression, surface, thickness & weight as compared with before laundering. Particularly, the LT and RT about $1\~3$ cycles of the repeated laundering showed remarkable decrease. And SMD, WC, T & W of fabrics for KFC by the laundering were more increased than one for original fabrics. But B, 2HB, G, 2HG, 2HGS were decreased more than one for original fabrics. 3. 'Stiffness', 'Anti-drape', 'Crispness' and 'Scroop' hand values decrease and'Fullness & softness', 'Flexibility & softness' hand values increase with repeated laundering. 4. Remarkable decrease are observed in crease recoveries about $1\~5$ cycles of the repeated lundering, but slack decrease are observed in crease recoveries after 5 cycles of repeated laundering. The crease recovery of fabrics for KFC have negative(-) correlation with LT, RT, G, RC and MMD, This fact implies that the smaller these values, the larger the crease recovery. The crease recovery of fabrics for KFC has a high degree of correlation with the mechanical properties such as shearing, compression, surface property. And also, the crease recovery are expected by measuring the mechanical properties such as G, 2HG, 2HGS, RC, WC, LC, MIU, MMD and SMD, according to the obtained regression equation.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.10
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• pp.1467-1477
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• 2002

This study was investigated physical properties of stretch fabrics by KES-FB system to show suitable basic data to making skirts of excellent capacity and develop more organized basic skirt pattern by fitness evaluation. 1. The results of T. H. V.(Total Hand Value) were as followa: In the kind of blending fiber, cotton/spandex was more excellent than nylon/spandex and polyester/spandex, in the direction of stretch, one-way(weft inserted polyurethan yarn) polyester/spandex and cotton/spandex were higher than two-way(warp and wet inserted polyurethan yarn) polyester/spandes and cotton/spandex, two-way nylon/spandex was higher than one-way nylon/spandex. 2. The results of calculating the variance between sample stretch fabrics and Japanese s/s women's suit fabrics after standardizing were as follows: Stretch fabrics has 2 range of tensile, bending, shearing, compression, surface, thickness and weight as compared with Jpanese s/s women's suit fabrics. In the tensile property, one-way stretch fabrics were almost the same with Japanese s/s women's suit fabrics, only two-way polyester/spandex had+1～+2 range. In the bending, shear property, there was no difference between sample fabrics and Japanese s/s women's suit fabrics 3. In the total fitness of the skirt, nylon/spandex is the best in the fabrics and one-way stretch fabric is better than two-way strethch fabric.

• The Korean Journal of Pain
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• v.34 no.3
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• pp.315-321
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• 2021

Background: Pillar pain may develop after carpal tunnel release surgery (CTRS). This prospective double-blinded randomized trial investigated the effectiveness of extracorporeal shock wave therapy (ESWT) in pillar pain relief and hand function improvement. Methods: The sample consisted of 60 patients with post-CTRS pillar pain, randomized into two groups. The ESWT group (experimental) received three sessions of ESWT, while the control group received three sessions of sham ESWT, one session per week. Participants were evaluated before treatment, and three weeks, three months, and six months after treatment. The pain was assessed using the visual analogue scale (VAS). Hand functions were assessed using the Michigan hand outcomes questionnaire (MHQ). Results: The ESWT group showed significant improvement in VAS and MHQ scores after treatment at all time points compared to the control group (P < 0.001). Before treatment, the ESWT and control groups had a VAS score of 6.8 ± 1.3 and 6.7 ± 1.0, respectively. Three weeks after treatment, they had a VAS score of 2.8 ± 1.1 and 6.1 ± 1.0, respectively. Six months after treatment, the VAS score was reduced to 1.9 ± 0.9 and 5.1 ± 1.0, respectively. The ESWT group had a MHQ score of 54.4 ± 7.7 before treatment and 73.3 ± 6.8 six months after. The control group had a MHQ score of 54.2 ± 7.1 before treatment and 57.8 ± 4.4 six months after. Conclusions: ESWT is an effective and a safe non-invasive treatment option for pain management and hand functionality in pillar pain.

• Transactions of Materials Processing
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• v.20 no.1
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• pp.11-16
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• 2011

Recently, according to the rapid development of display, many display applications, such as, cellular phone, navigation, monitor and LCD TV have been changed from CRT type to LCD type. BLU(Back Light Unit) is one of main parts in LCD unit and generally, it consists of a light source, a reflective sheet, a LGP(Light Guide Plate), a diffuser sheet, and two prism sheets. The most important component of BLU is a light guide plate, which diffuses the input light to the TFT-LCD module uniformly. The LGP is usually made by injection molding process, and it has numerous optical micro patterns on the surface. In the present study the micro-patterned stamper which has cylindrical shape was fabricated by using the UV-LiGA process. And the replication characteristics have been compared among three different kinds of injection molding process; general injection molding, injection/compression molding and RHCM(Rapid Heating and Cooling Molding). Average replication ratios of CIM and ICM were 19.1% and 64.6%, respectively. On the other hand, the average replication ratio of RHCM process showed the higher value of 98.4% among these. It show that maintaining the mold surface above $T_g$ could increase the replication ratio of micro patterns substantially.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.6
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• pp.531-548
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• 2006

The purpose of this study was to investigate the biomechanical, histologic findings of distracted regenerate and TMJ response in modified distraction osteogenesis (DO) technique combined with compression force as biomechanical stimulation method which has been suggested in 2002, and developed thereafter by authors. This study was performed with two experiments. First experiment was designed to explore the optimal ratio of compression force versus distraction force for the new DO technique. Second experiment was planned to evaluate the reaction of TMJ tissue, especially condyle, disc after application of the DO technique with compression force. Total 52 New Zealand adult male-rabbits with 3.0kg body weight were used for the study. For the first study, 30 adult male-rabbits underwent osteotomy at one side of mandibular body and a external distraction device was applied on each rabbit with same manner. In the control group of 10 rabbits, final 8 mm of distraction with 1 mm rate per day was done with conventional DO technique after 5 latency days. For the experimental group of 20 rabbits, a compression force with 1 mm rate per day was added to the distracted mandible on 3-latency day after over-distraction (over-lengthening). As the amount of the rate of compression versus distraction, experimental subgroup I (10 rabbits) was set up as 2 mm compression versus 10 mm distraction (1/5) and experimental subgroup II (10 rabbits) was set up as 3 mm compression versus 11 mm distraction (about 1/3). All 30 rabbits were set up to obtain final 8 mm distraction and sacrificed on postoperative 55 day to analysis on biomechanical, and histologic findings of the bone regenerates. For second study, 22 adult male-rabbits were used to evaluate TMJ response after the DO method application with compression force. In the control group, 10 rabbits was used to be performed with conventional DO method, on the other hand, in a experimental group of 10 rabbits, 10 mm distraction with 2 mm compression (1/5 ratio) was done. The remaining 2 rabbits served as the normal control group. Histomorphologic examinations on both condyle, histological studies on condyle, disc were done at 1, 2, 3, 4, 7 weeks after distraction force application. The results were as follows: 1. On the bone density findings, the experimental group II (force ratio - 1/3) showed higher bone density than the other experimental group (force ratio - 1/5) and control group (control group - $0,2906\;g/cm^2$, experimental group I - $0.2961\;g/cm^2$, experimental group II - $0.3328\;g/cm^2$). 2. In the histologic findings, more rapid bone maturation like as wide lamellar bone site, more trabeculae formation was observed in two experimental groups compared to the conventional DO control group. 3. In morphologic findings of condyle, there were no differences of size and architecture in the condyle in the control and experimental groups. 4. In histologic findings of condyles, there were thicker fiberous and proliferative layers in experimental group than those of control group until 2 weeks after distraction with compression force. But, no differences were seen between two groups on 3, 4, 7 weeks after compression. 5. In histologic findings of disc, more collagen contents in extracellular matrix, more regular fiber bundles, and less elastin fibers were seen in experimental group than control group until 2 weeks after distraction with compression. But, no differences were seen between two groups on 3, 4, 7 weeks after distraction with compression. From this study, we could identify that the new distraction osteogenesis technique with compression stimulation might improve the quality of bone regeneration. The no remarkable differences on TMJ response between control and experimental groups were seen and TMJ tissues were recovered similarly to normal TMJ condition after 3 weeks.

• Journal of Korean Neurosurgical Society
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• v.64 no.6
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• pp.944-949
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• 2021

Objective : The stability is an important factor to decide the treatment plan in thoracolumbar burst fracture patients. Patients with an unstable burst fracture generally need operative management. Decrease in vertebral body height, local kyphosis, involvement of posterior column, and/or canal compromise are considered important factors to determine the treatment plan. On the other hand, in thoracolumbar injury classification system (TLICS), surgery is recommended in patients with TLICS of more than 5 points. The purpose of this study was to apply the TLICS score in patients with thoracolumbar burst fractures and to distinguish the differences of treatment plan on burst fracture. Methods : All patients, diagnosed as a thoracolumbar burst fracture between January 2006 and February 2019 were included in this study. Unstable thoracolumbar burst fracture was defined as burst fracture with neurologic deficit, three-column injury, kyphosis over 30 degrees, decrease of anterior body height over 40 percent and canal comprise more than 50%. TLICS score was measured with morphology, neurological involvement and posterior ligamentous complex integrity. The existence of instability was compared with TLICS score. Results : Total 233 patients (131 men, 102 women) were included in this study. In Denis classification, 51 patients (21.9%) diagnosed as stable burst fracture while 182 patients (78.1%) had unstable burst fracture. According to TLICS, 72 patients (30.9%) scored less than 4, while 161 patients (69.1%) scored 4 or more. All the patients with stable burst fracture scored 2 in TLICS. Twenty-one patients (9.0) scored 2 in TLICS but diagnosed as unstable burst fracture. Thirteen patients had over 40% of vertebra body compression, four patients had more than 50% of canal compromise, three patients had both body compression over 40% and kyphosis over 30 degrees, one patients had both body compression and canal compromise. Fifteen patients presented kyphosis over 30 degrees, and three (20%) of them scored 2 in TLICS. Seventy-three patients presented vertebral body compression over 40% and 17 (23.3%) of them scored 2 in TLICS. Fifty-three patients presented spinal canal compromise more than 50%, and five (9.4%) of them scored 2 in TLICS. Conclusion : Although the instability of thoracolumbar burst fracture was regarded as a critical factor for operability, therapeutic strategies by TLICS do not exactly match with the concept of instability. According to the concept of TLICS, it should be reconsidered whether the unstable burst fracture truly unstable to do operation.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.193-196
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• 1996

A pneumatic cylinder has been used in the production facilities of various industries. However, it is difficult to achieve deciding the precise position of the piston rod, due to the nonlinear properties arising from the air compression and the friction. In recent years, the fuzzy control algorithm has been frequently applied to various kinds of systems on account of its simple algorithm, good adaptability to complex or nonlinear systems and so on. On the other hand, the PID or I-PD control has been used in many engineering fields because of the excellent performance. However, it is known that each one of them has disadvantages. In this paper, we propose a hybrid control which is strived to obtain the advantages of each other. It is shown that the proposed hybrid control performs better than the conventional I-PD control through the experimental results.

• Applied Microscopy
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• v.45 no.4
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• pp.208-213
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• 2015

Nanomanipulators installed in focused ion beam (FIB), which is used in the lift-out of lamella when preparing transmission electron microscopy specimens, have recently been employed for electrical resistance measurements, tensile and compression tests, and in situ reactions. During the pick-up process of a single nanowire (NW), there are crucial problems such as Pt, C and Ga contaminations, damage by ion beam, and adhesion force by electrostatic attraction and residual solvent. On the other hand, many empirical techniques should be considered for successful pick-up process, because NWs have the diverse size, shape, and angle on the growth substrate. The most important one in the in-situ precedence, therefore, is to select the optimum pick-up process of a single NW. Here we provide the advanced methodologies when manipulating NWs for in-situ mechanical and electrical measurements in FIB.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.7
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• pp.885-893
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• 2012

DME (Dimethyl ether) is regarded as one of the candidates of alternative fuels for diesel engine, because of its higher cetane number suitable for a compression ignition engine. Also, DME is a simple chemical structure, colorless gas that is easily liquefied and transported. On the other hand, Bunker oil (JIS C heavy oil) has long been used as a basic fuel in marine diesel engines and is the lowest grade fuel oil. In this study, the combustion and emission characteristics were measured experimentally in the direct injection type diesel engine operated with DME and Bunker oil mixed fuel. From our experimental results, it is induced that DME and Bunker oil blended fuel would be an effective fuel which can reduces the concentration of harmful matter in exhaust gases.