• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.470-477
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• 2015

This study was carried out to investigate the change of dimensional stability of thermally compressed Korean pine (Pinus koraiensis Sieb. et Zucc.) wood by post heat treatment. Specific gravity of compressed wood was notably increased with thermal compression. In the compression set 50%, compressed Korean pine showed a specific gravity of 0.84. The amount of water absorption and swelling of thermally compressed Korean pine decreased with increasing temperature and time of the heat treatment. Set recovery also decreased with increasing temperature and time of heat treatment. Thermally compressed Korean pine that heat-treated in $120^{\circ}C$ for 24 hours showed a set recovery of 3.8%, whereas non-treated group showed 11.5%. Therefore, it was confirmed that the thermal treatment was a very effective method for the dimensional stability of the heat compressed wood.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.3 s.31
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• pp.187-196
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• 1989

The purpose of this study is to find at the basic data for the appropriate compressibility of the pillows for the Koreans as well as, for the appropriate conditions to establish the estimating criterion for the pillows on the market place. This paper also aim to grasp thr compressibility of the materials used to make the pillows for sale. The appropriate compressive rate of the pillows have been investigated by sensuous test. The compressive rate, recovery rate, and decreasing rate of compression and recovery have been investigated by means of ergonomic and physical experiments. The results were as follows; 1) By sensuous test, the compressive rate of the pillows for the most comfortable state turns up $45\%{\pm}5\%$ in men and women. 2) As for the compressive rate and recovery rate of the eight pillow materials on market, panya, duck feather two kinds of synthetic fiber are highest, wood is lowest. 3) The compressive rate of panya, duck feather, and two kinds of fiber is within the range of the comfort by sensuous test. 4) In the durability of the compressive rate and recovery rate against the repeated use of the pillows, duck feather is in the highest grade, panya is the lowest grade and the others are graded between two.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.3
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• pp.495-505
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• 2016

This study explores and selects an appropriate material that considers light and soft physical properties as well as activity for impact absorption pads that can be used to develop practical impact protective clothes worn during daily life by the elderly to reduce the impact of falls. Physical properties, impact absorption performance, and compression characteristics were evaluated on 5 types of foam, 2 types of 3D spacer fabric, and 3 types of polymer gel to select a material appropriate for the pad to be inserted into impact protective clothes. The evaluation of the physical properties showed that 3D spacer fabrics had lower density compared to other materials and polymer gels had the highest density. The elongation percentage was higher in foams than 3D spacer fabrics and EPDM foam had the highest elongation percentage. The impact absorption performance of honeycomb polymer gel was better than foams and 3D spacer fabrics. As a result of looking into compression energy and compression characteristics of materials, 'CR foam A' was found to absorb the largest amount of compression energy, 24.1%, among foams and polymer gels. A high energy absorption rate of 50.0% (or above) was indicated by 3D spacer fabrics; however, foams and polymer gels showed a progressive deformation of energy compression / recovery curve with 3D spacer fabrics that showed drastic deformation. Based on characteristics of materials, 'CR foam C' and EPDM with relatively high absorption performance can be used as protective pad materials among foams. Among polymer gels, 2 open-type polymer gels that have relatively low impact protective performance but a relatively lighter weight on human body (compared to closed-type) are considered appropriate protective pad materials.

• Textile Coloration and Finishing
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• v.33 no.2
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• pp.87-95
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• 2021

In this study, the application of a medical compression sleeve of Moisture Responded Transformable(MRT) fibers to the treatment of lymphedema after surgery in breast cancer patients was investigated. MRT fibers were manufactured with PET and Nylon6 bi-component cross-section yarns, and compression sleeves of sleeves 1, 2, 3, and 4 were knitted in order of size, and then the physical properties and clinical tests were evaluated. As a result, the pressure of compression sleeve in wrinkle was the lowest in sleeve 1 with 3.81 kPa, and the highest in sleeve 4 with 5.22 kPa. Elastic recovery rate is that all parts except the top of the sleeve 1 exhibited 100%. The air permeability was good at 12.1 ~ 16.1 cm³/cm²/sec, and peeling was also comparatively excellent as grade 3. In addition, the weight of the compression sleeves 1, 2, and 3 decreased as 18.3 ~ 23.0 g/m² depend on size, while the compared sample was heavier with 17.39 ~ 32.61 g/m². In lymphoscintigraphy test, it was confirmed that the function of remaining lymph node was good in all patients. Although there were no differences between samples in skin irritation and tightness in wearing comfort, the manufactured sleeves showed better fit, lightness, fashion and breathability than the comparable sleeves.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.4
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• pp.101-107
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• 2009

Actuators using shape memory alloys use the one-way shape recovery stress. But when external load is applied the accumulated plastic strain induced by repeated deformation is the factor of generation of uncorrect recovery stress and unreliability. To solve this problem, two-way shape memory effect (TWSME) is considered. TWSME induced by plastic deformation have advantages including simple heating cycle without external force and enough recovery force for using actuators. but there is no research on cylinder-type or tube-type shape memory alloy actuators using two-way shape memory effect until now. Therefore in this study, characteristics of two-way shape memory effect is verified through the compression experiments using cylinder-type and tube-type specimens.

• Korean Journal of Human Ecology
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• v.24 no.1
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• pp.97-109
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• 2015

Recently, because the market for compression wear now includes all consumers, not just professionals, various items for recovery after exercising or for enhanced effects from exercise have been introduced. In this research, a systematic and stepwise design process was proposed to develop compression garment that has both functional area and appropriate pressure to protect the knee when exercising. The U-V format functional area that wraps underneath the knee was selected by considering the shape and change in the skin length when bending the knee. After the selection of the functional area, a total of seven knee design areas, including the existing product, were designed to determine the appropriate pressure. After various movements, the compression garment was ranked in terms of support of the knee, level of pressure, discomfort of seam line, and comfort of popliteal; the preferred design was selected using the quad method. Four compression wear garments were produced using two selected preferred designs; the wear evaluation was performed using a seven-point Likert scale. As a result, the optimal reduction rate of the pattern was calculated based on Ziegert and Keil's method. The applied percentage of the fabric stretch at the upper part of the crotch was 66% for the width and 50% for the length; for the lower part of the crotch, only 66% for the width was applied. Moreover, it was determined that the design of the U-V knee protection part was preferred when a 7 mm square was placed at a 1 mm distance because this not only supports the knee but also allows the fabric to accommodate various skin deformations.

• Journal of Korean Orthopaedic Sports Medicine
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• v.5 no.1
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• pp.63-68
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• 2006

Purpose: To assess the effectiveness of the Locking compression plate (LCP) after open reduction for the treatment of the displaced clavicular shaft fracture, the clinical and radiologic outcome of the patients who were managed with the LCP for internal fixation after open reduction has been analyzed. Materials and Methods: We reviewed 26 cases with a displaced clavicular shaft fracture treated by internal fixation using Locking compression plate after open reduction between May 2003 and November 2004. The patients were followed up for at least six months period, and final postoperative outcome was evaluated using clinical results based on Kang's criteria, radiologic signs of fusion. Results: All fractures united by an average of 9.3 weeks without delayed union and showed fast recovery of motion fraction and shoulder function. In addition,24 cases without the fractures of proximal humerus recovered to normal range of shoulder notion within 2.9 weeks. Clinically, according to Kang's criteria, the outcome was good or better in 22 patients. The complications included shoulder joint dysfunction in two cases and keloid formation in one case, and no other complications were observed. Conclusion: The internal fixation using LCP for the treatment of displaced clavicular shaft fracture is a safe, reliable method of treatment, with few complications, and offers rapid recovery of shoulder joint function and bone union.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2
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• pp.365-372
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• 2000

he paper introduces evolutionary computing to Fractal Image Compression(FIC). In Fractal Image Compression(FIC) a partitioning of the image into ranges is required. As a solution to this problem there is a propose that evolution computation should be applied in image partitionings. Here ranges are connected sets of small square image blocks. Populations consist of $N_p$ configurations, each of which is a partitioning with a fractal code. In the evolution each configuration produces $\sigma$ children who inherit their parent partitionings except for two random neighboring ranges which are merged. From the offspring the best ones are selected for the next generation population based on a fitness criterion Collage Theorem. As the optimum image includes duplication in image data, it gets smaller in saving space more efficient in speed and more capable in image quality than any other technique in which other coding is used. Fractal Image Compression(FIC) using evolution computation in multimedia image processing applies to such fields as recovery of image and animation which needs a high-quality image and a high image-compression ratio.

• The Korean Journal of Pain
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• v.22 no.2
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• pp.176-180
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• 2009

Cases of pyogenic spondylodiscitis are relatively rare diseases that concern 2-7% of total cases of osteomyelitis. Owing to the low frequency and initial nonspecific nature of signs and symptoms, diagnosis is often delayed up to 2-6 months. If the proper treatment is not established due to a diagnostic delay, there is a possibility of a serious neurologic deficit and spinal instability. We report two cases of infectious spondylodiscitis which were misdiagnosed as compression fracture and spinal stenosis respectively. They could be correctly diagnosed after MRI and laboratory test and under the recovery state after an antifungal and antibiotic medication. Special careful attention during the diagnostic procedure is a really important step considering the diagnostic delay and its resultant unsatisfactory outcome.

• Journal of the Korean Society of Clothing and Textiles
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• v.11 no.2 s.24
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• pp.13-21
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• 1987

Nowadays, the amount used carpets are on the increase, according to the improvement of life-style. The pleasantness of carpet is caused by the properties of pile, because the most carpets are made pile fabric. For that reason, a study on the compressional properties of carpet is very important issue. This study has been carried out to investigate the differences of compressional properties in various acrylic carpets which were Cut, Tufted, Jacquard and Shag. Each acrylic carpets was transformed to 4, 6, 8 mm of pile height, as results of transformation, we could get the pressure-thickness curve and pressure-deformation curve. The results are summarized as follows. 1. Rate of compression increases, compressive resistance and compressive elasticity decr-eases, as pile height increases. 2. Regardless of pile height, compressive elasticity reached the limit in recovery period at about 10 minutes. 3. Work of compression increases, as pile height increases. 4. Work of compression decreases, as apparent density increases. 5, Cut-type carpet has the best cushion.