• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.264-265
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• 2003

프로젝션 디스플레이 장치에 있어서 광학적인 효과 면에서 반사형 Light Valve (DLP, LCoS 등)를 주로 사용하고 있는데 이는 제작 프로세스 상 투과형에 비해 고 가격이므로 3판식 방법 보다는 단판식 방법이 선호되고 있다. 그러나 그림 1 에서 보이는 바와 같이 단판식의 경우 구조적 시스템은 단순하지만 광의 사용 효율이 3판식 방법에 비해 1／3 수준으로 낮아지기 때문에 광의 사용효율을 높이기 위해 여러가지 방법이 시도되고 있는 실정이다. (중략)

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.1-4
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• 1985

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.27-35
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• 2007

This experiment was carried out to investigate the appearance and surface gluing characteristics of laminated boards overlaied with teak sliced veneer, printing paper, wall paper, cotton cloth, and wool cloth, The overlaying sheets were glued on the laminated boards with polyvinyl acetate emulsion adhesives and the species for laminated boards was red pine. The obtained results are summarized as follows; in case of the teak sliced veneer overlaied boards, the appearance quality was very good and showed the first grade of KS standard. but the delamination rate was 44.0% and 895% for cold water or warm water dipping treatments, respectively, so the wet gluing properties were very bed. In the case of the paper or cloth overlaied boards, the appearance quality was same good and showed the first grade of KS standard, but their delamination rate was 10~20% and 39.3~49.0 for cold water or warm water dipping treatments, respectively, so the wet gluing properties were bed, relatively better than sliced veneer overlaied boards. The present work showed that appearance of laminated boards overlaid with several sheets appeared quite positive in terms of secondary gluing qualities of laminated boards, suggesting that sliced veneer, paper, and cloth would be appropriate for the overlaying materials of laminated boards.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.317-317
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• 2008

기존의 초음파 노즐은 단판액츄에이터형 초음파 노즐을 사용하여 연체 연료를 분사하였다. 하지만 단판액추에이터형 초음파 노즐은 300V이상의 고전압을 필요로 하여 소비전력이 높은 단점을 가지고 있다. 하지만 적층액츄에이터형 초음파 노즐은 저전압 구동이 가능하여 낮은 소비전력을 가지며, 단판액츄에이터헝 초음파 노즐보다 우수한 분사특성을 가지고 있는 장점이 있다. 또한 공진형 인버터를 사용하여 초음파 노즐을 구동하는 경우 노즐의 구동 전압을 공진에 의하여 쉽게 얻어질 수 있는 장점과 구동 스위치에 가해지는 전압의 크기가 상대적으로 작게되므로 인버터 구동에 저전압 MOSFET를 사용함으로써 도통손실의 저감 및 구성회로의 저압화 등에 유리한 이점이 있다. 본 연구에서는 적층액츄에이터형 초음파노즐을 개발하고 그에 따른 공진형 인버터를 설계하여 적층엑츄에이터형 초음파 노즐의 분사 시스템을 제안 한다. 또한 실제 액체연료인 경유를 분사하여 전기적특성과 분사특성을 조사한다.

• Journal of the Korean Wood Science and Technology
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• v.12 no.1
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• pp.11-30
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• 1984

This study was executed to offer the basical data needed to the plywood industry as examining on the wood characteristics of veneer species that grow in Korea. According to the aggravation of log import from foreign countries caused by the gradual exhaustion of wood resources in recent years, the study on wood characteristics of veneer species growing in Korea should be carried out preferentially in promotion of the domestic timber utilization and development of it's processing technique for plywood industry. 50 commercial veneer species in this study were selected from 33 genuses, and general macroseopical wood characteristics for them were examined and described by the species. And also keys for the identification based on gross features were briefly prepared and presented by gymnosperm and angiosperm respectively.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.39-50
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• 1999

This research was carried out to investigate the development of fire-retardancy treatment technology and performance evaluation of fire-retardant treated plywoods. Radiata pine, keruing, dillenia, calophyllum and terminalia veneers were treated by normal(conventional) pressure soak(NPS) and vacuum-pressure-soak(VPS) using 20% water solution of diammonium phosphate. Then, 4.8mm thick, 3ply plywoods were fabricated with combination of fire-retardant treated, untreated or water-immersion types and several composition types of radiata pine and keruing veneers, i,e. the uniform and the mixed types in species composition, and the homogenious and the alternate layer types in veneer treatment. In composed species, the retention and the treatment effects of fire-retardant chemicals III radiata pine was still greater than those of keruing. The effect of VPS treatment was larger than that of NPS treatment, however, adhesive bonding strength and bending strength of plywoods treated by these two methods were not necessarily lowered, compared to those of untreated plywood. And also, fire endurance performance of the urea melamine resin-bonded plywood was greater than that of the phenol resin-bonded plywood. In result, the appropriate combination in veneer species and layer as well as alternate fire-retardant treatments would be more efficiently available in service.

• Journal of Korean Society of Forest Science
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• v.30 no.1
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• pp.8-18
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• 1976

This study was carried out to exploit and utilize the exotic American Sycamore(Platanus occidentalis) grown in Korea as a veneer species for plywood manufacture. At present most parts of veneer Legs used in Korea were depended entirely upon the gonus Shorea woods(lauan logs) imported from Southeast Asia region. To decrease manufacturing cost and save imported lauan veneer logs, the effects on properties affecting to the six types of plywood made from proper veneer constructions composed by domestic American Sycamore and imported lauan veneers were compared and discussed. The study has important meanings for the promotion of plywood manufacture by domestic materials. Important items dealt with this study were dry and wet shear strength, moisture contents, specific gravties, and bending strength. By the results and discussions it may be summarized as follows: 1) In dry shear strength platanus(sycamore) core lauan plywood was shown most excellent strong results, and next orders were all lauan plywood, platanus faced lauan plywood, lauan core platanus plywood, lauan faced platanus plywood, and all platanus plywood. There was no difference between platanus core lauan plywood and all lauan plywood, but the differences between those plywoods and the other types of plywood were recognized. 2) In wet shear strength platanus core lauan plywood was shown excellent result the same as dry strength. The difference between platanus core lauan plywood and the other types of plywood was shown, but among the other types of plywood except platanus core lauan plywood were not recognized. 3) The differences among moisture contents according to the veneer construction were not recognized. 4) The plywood constructed by two or more sheets of lauan veneer was shown lower specific gravities than the plywood constructed by two or more sheets of platanus veneer. It is believed that this tendency due to the original specific gravities of veneer before construction. 5) The differences among specific gravities of lauan core platanus plywood, all platanus plywood and lauan faced platanus plywood were not recognized, and like this analyzed result among platanus core lauan plywood, all lauan plywood and platanus faced lauan plywood were not recognized. Accordingly it is believed that the differences are not shown among the plywood constructed by two or more veneers of same species. 6) In bending strength platanus core lauan plywood was shown most excellent values. Next orders were all lauan plywood, platanus faced lauan plywood and the other types of plywood. The differences among the plywood constructed by two or veneers of lauan were shown, but not shown among the plywood constructed by tow or more veneers of platanus.

• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.154-161
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• 2020

Purpose: To describe the clinical and radiology results of a surgical treatment for clinodactyly due to a longitudinal epiphyseal bracket. Materials and Methods: This study analyzed the records of 11 patients (27 case) with clinodactyly due to a longitudinal epiphyseal bracket who underwent an osteotomy or physiolysis between March 1999 and April 2017. The preoperative range of motion of the proximal and distal interphalangeal joints, the subjective satisfaction of the patient, and the degree of angulation to the ulnar side were examined. The patients were classified into two groups: osteotomy and physiolysis. The results were reviewed retrospectively and compared according to the surgical method. Results: The mean age of the patients who underwent osteotomy was 10.3 years. The average preoperative angle was 25.7° and the average postoperative angle was 13.5° the mean correction rate was 47.4%. The mean age of the patients who underwent physiolysis was 6.0 years the mean preoperative angle was 24.5° and the postoperative angle was 10.7°. The average correction rate was 59.4%. No significant difference in the correction angles was observed between the group who underwent the correction osteotomy and the group who underwent the osteotomy. In each group, the postoperative correction was statistically significant. The range of motion at the last follow-up was not significantly different from the preoperative range of motion. Conclusion: In patients with clinodactyly due to longitudinal epiphyseal bracket, osteotomy or physiolysis may be performed selectively according to age, bone age, and radiological progression. Both surgical methods showed good clinical results and deformity correction.

• Journal of the Korean Wood Science and Technology
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• v.1 no.1
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• pp.10-12
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• 1973

• Journal of the Korea Furniture Society
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• v.11 no.1
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• pp.61-68
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• 2000

This study was carried out to investigate the effect of grain and veneer thickness on drying rate, required energy consumption, and drying defects such as checking, end waving, and burning during a far-infrared radiation drying process of decorative veneers of hard maple and beech. Most of the veneer could be dried from green to in-use moisture content within 30 to 360 seconds. The drying rates were significantly affected by veneer thickness, but there was little difference between edge-and flat-sliced veneers. The formation of checking during drying test was none or very slight. The percentages of the veneers defected by checks were higher in the flat-sliced veneers than in the edge-sliced veneers. The maximum end wavinesses in the flat-sliced veneers were almost 1.6 to 3 times larger than that in the edge-sliced veneers. All veneers were fee from burned marks during drying test.