• 기술사
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• 제15권4호
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• pp.12-24
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• 1982

East Parts of Bangladesh have been benifited by low cost energy generated by domestic natural gas but West parts where energy generated by imported fuel. Bangladesh Government authority has very much concerned to transmit the low cost electricity to the West from the East for past several years. To solve such concerns, cross-country 230kv double circuits Power transmission line was proposed, however there was a big obstacle for the realization of this line to cross the Jamuna river which has 12 km long width with a deep muddy river bed. A consultant engineering firm named Merz-Mclellan anyway finalized this plan and a world-wide bid was announced on June 31, 1979. Due to the expected difficulty to construct the towers on sea like area, only three construction groups have participated. including a Korean joint venture organization of Samsung-Korean Developement corporation-Kolon Electric Machinery company. After 3 months bid evaluation, contract was awarded to Korean Consosium and KEM Co was in charge of designing steel towers with anchor bolts and base plates beside to electrical engineering field. Then KEM Co have faced and over-comed many unenpected technical difficulties such as forced eccentricity joint on base plate, distorsion issue of 60mm thick plates welding, threading anchor bolts, tad heat treatment of some anchor bolts, disagreement from Consultant Engineer on multiplying factor of leg stresses for 45$^{\circ}$ wind and on reducing O.L.F for wind loads on cables for such 1220km long spans. After spending two years long period for designing and engineering towers, base plates, and anchor bolts, first shipment of tower was finally realized on Nov. 8, 1981 and on the other hand KDD has proceeded concrete caisson work on schedule at Jamuna river site and expected to complete tower erection and stringing of cables within this year of 1982 which was original completion target.

• 한국작물학회지
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• 제31권1호
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• pp.62-67
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• 1986

수확 후 3주와 8주에 맥주보리 49개 품종의 발아세, 발아율 및 수감수성의 품종간 차이를 검토하고자 실험한 결과를 요약하면 다음과 같다. 1. 수확 후 3주에 발아상의 물량 증가에 따른 발아세, 발아율, PI치와 수감수성의 차이는 컸으나 8주에는 그 차이가 적어서 휴비성이 발아세와 발아율을 저하시켰다. 2. 발아세는 휴비성이 소거된 8주에는 전 공시 품종이 극히 양호하였으며, CI 12062와 CI 15631등의 수감수성이 다소 커서 광범위한 육종재료를 교배에 이용할 경우 수감수성의 검정이 필요할 것으로 본다. 3. 수감수성은 저장기간에 관계없이 물 8ml 발아세, 발아율, PI치와 상관이 매우 높았으나 물 4ml에서는 상관관계가 없었다. 4. 저장기간, 품종 및 곡립의 풍만도에 따라서 발아세와 수감수성의 차이가 있으므로 등숙이 양호한 품종의 육성과 등숙향상을 위한 재배법이 연구되어야 할 것으로 생각된다.

• 한국도로학회논문집
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• 제16권6호
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• pp.79-86
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• 2014

PURPOSES : In this study, wasted vinyl aggregate, which possesses better thermal properties than natural aggregate, was used in cement concrete mixture to develop more economical concrete with thermal insulation and freeze prevention effects. METHODS : Slump and air content of the fresh concrete, which substituted its 0%, 5%, and 10% of coarse aggregate with wasted vinyl aggregate, were measured. Compressive strength, Poisson's ratio, elastic modulus, and splitting tensile strength of hardened concrete were measured by laboratory tests. Thermal properties of concrete such as coefficient of thermal expansion, thermal conductivity, and specific heat were also measured according to replacement ratio of wasted vinyl aggregate. Finally, the thermal insulation and freeze prevention effectiveness of the concrete mixed with wasted vinyl aggregate was confirmed through finite element analysis of road pavement crossing above concrete box culvert made from wasted vinyl aggregate. RESULTS : Even though the physical properties of wasted-vinyl-aggregate concrete such as compressive strength, Poisson°Øs ratio, elastic modulus, and splitting tensile strength were inferior to those of ordinary concrete, they met requirements for structural concrete. The thermal properties of concrete were improved by wasted vinyl aggregate because it decreased thermal conductivity and increased specific heat of the concrete. According to the result of finite element analysis, temperature variation in pavement subgrade was mitigated by box culvert made from wasted-vinyl-aggregate concrete. CONCLUSIONS : Through the laboratory test and finite element analysis of this study, it was concluded that the concrete structures made from wasted vinyl aggregate showed thermal insulation and freeze prevention effects.

• 한국환경과학회지
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• 제26권12호
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• pp.1341-1353
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• 2017

This study aimed to identify the aquatic and riparian factors associated with the presence/absence of the Eurasian otter in the Nakdong river basin, where the species is relatively more abundant than other otter species. Environmental factors and presence records were collected. Geographical Information System technology and chi-square test were used to compare environmental gradients in aquatic and riparian factors between presence and absence sites. Aquatic habitat attributes were evaluated with natural riverside sandbars and channel crossing artificial structures, the ratio of channel width to alluvial plain width, riverbed substrate, and flow diversity. Riverbank characteristics, bank materials, man-made embankment types, and land use/land cover of inland and riverside areas were selected as riparian habitat attributes. Compared to the aquatic attributes, riparian attributes were highly significant when assessing otter presence and absence sites, suggesting that conservation of suitable riparian areas to provide maternity and resting areas for otter species is essential in the Nakdong river basin. None of the aquatic attributes examined were statistically significant when evaluating otter presence or absence. These results indicate that the presence of suitable riparian area for resting and reproduction habitats is more critical to the presence of Eurasian otter than food availability in aquatic areas. To inform implementation of effective conservation actions, broad-scale factors, such as watershed attributes, would be needed to further assess habitat conditions of the Eurasian otter.

• Structural Monitoring and Maintenance
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• 제1권1호
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• pp.131-157
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• 2014

Special track systems used to divert a train to other directions or other tracks are generally called 'railway turnout'. A traditional turnout system consists of steel rails, switches, crossings, steel plates, fasteners, screw spikes, timber bearers, ballast and formation. The wheel rail contact over the crossing transfer zone has a dip-like shape and can often cause detrimental impact loads on the railway track and its components. The large impact also emits disturbing noises (either impact or ground-borne noise) to railway neighbors. In a brown-field railway track where an existing aged infrastructure requires renewal or maintenance, some physical constraints and construction complexities may dominate the choice of track forms or certain components. With the difficulty to seek for high-quality timbers with dimensional stability, a methodology to replace aged timber bearers in harsh dynamic environments is to adopt an alternative material that could mimic responses and characteristics of timber in both static and dynamic loading conditions. A critical review has suggested an application of an alternative material called fibre-reinforced foamed urethane (FFU). The full-scale capacity design makes use of its comparable engineering characteristics to timber, high-impact attenuation, high damping property, and a longer service life. A field trial to investigate in-situ behaviours of a turnout grillage system using an alternative material, 'fibre-reinforced foamed urethane (FFU)' bearers, has been carried out at a complex turnout junction under heavy mixed traffics at Hornsby, New South Wales, Australia. The turnout junction was renewed using the FFU bearers altogether with new special track components. Influences of the FFU bearers on track geometry (recorded by track inspection vehicle 'AK Car'), track settlement (based on survey data), track dynamics, and acoustic characteristics have been measured. Operational train pass-by measurements have been analysed to evaluate the effectiveness of the replacement methodology. Comparative studies show that the use of FFU bearers generates higher rail and sleeper accelerations but the damping capacity of the FFU help suppress vibration transferring onto other track components. The survey data analysis suggests a small vertical settlement and negligible lateral movement of the turnout system. The static and dynamic behaviours of FFU bearers appear to equate that of natural timber but its service life is superior.

• 복식
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• 제51권1호
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• pp.21-32
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• 2001

Gauze is very light and thin. Their warps are entangled and their structure is loose. It is natural that they are easier to decay than other silk fabrics through physiochemical processes over a long period of time. Nonetheless quite many remains of Gauze fabrics can be found in China or Japan as well as in Korea. Various Gauze was used in costumes since the era of the Three Kingdoms and their weaving techniques, such as using gold threads with silk-fabrics, was developed in Koryo dynasty era, which made it possible to create more magnificent gauze fabrics in Korea. Relatively a lot of Gauze fabrics are remained in Korea. Based on these corroborative relics, this thesis analyzes the characteristics of gauze fabrics possesed in Korea and categorizes the gauze fabrics described in the Decrees on Costume Restraint of the King Hungduk. This also compares them with the present gauze in other countries. The types of gauze fabrics are generally divided into desined gauze, and non-designed gauze, the one without pattern. There ar a lot of desined gauze, such as dyeing gauze, brocade gauze, embroidery with gauze ground, patterned gauze with gauze ground etc. which were found in Korea and also in China and Japan. Non-designed gauze is divided into 2-end complex gauze, 3-end complex gauze, 4-end complex gauze, etc depending on the number of crossing warps. All of the non-designed gauze of Koryo dynasty found in Korea was 4-end complex gauze fabrics. These non-designed gauze fabrics were also found in Japan and China.

• 한국지진공학회논문집
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• 제3권2호
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• pp.67-76
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• 1999

이동하중에 의한 교량의 공진현상은 차량의 속도와 유효타격간격에 의해 결정되는 이동하중의 운행진동수와 교량의 고유진동수가 일치할 경우 발생하게 된다. 철도교의 경우에는 정해진 열차만 통행하게 되므로 이러한 유효타격간격이 정량적으로 정해져있다 본 연구에서는 고속전철하중을 받는 교량의 지간장 변화에 따른 교량의 공진현상과 공진소멸현상을 분석하고자 한다. 강합성형 철도교에 대하여 판요소와 공간뼈대요소의 조합에 의한 3차원 모델링을 적용하였으며 또한 고속전철하중은 이동집중하중 모델과 3차원 모델링 두가지 방법을 사용하였다 수치예제로서 지간장 변화에 따른 수직처짐의 동적확대계수 상판의 최대수직가속도 단부회전각 등의 동적응답 분석을 통하여 고속철도 교량의 동적안정성에 적합한 지간장 설계기준에 대하여 논의 하였다.

• 복식문화연구
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• 제23권2호
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• pp.294-309
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• 2015

This study aims to clarify the aesthetic values between emotion of human and expression of technology in contemporary fashion as it analyzes formative characteristics of related cases in fashion based on principles of 3D Printing technology and the viewpoint of mechanic aesthetics. The conclusions of this study are as follows. First, 3D Printing fashion is not only expressed diverse variations by its principles of formative methods, materials and properties, but also changes of silhouette by applying system of designers. Second, general characteristics of 3D Printing fashion is represented by various applications in SLS system, and it can be specifically explained application to a portion of clothing, decorative roles of clothing, complicated pattern making through crossing fabrics using 3D scanner and displaying a certain object changing fashion styles, and so forth. Third, the formative characteristics of 3D Printing fashion from the perspective of mechanic aesthetics is as follows. It can be analyzed as the integration of metaphysical values through compared symbolization of natural feature and technical evolution, partial dynamics and interactive velocity-based, formative combinations for abstract expression using architectural components, cosmos images and substantialized structures through images of organic space interacted human shapes. As the mention above, 3D Printing technology can creative a diverse area of fashion, and express images of new technological fashion through various works with continuous development of techniques.

• Archives of Plastic Surgery
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• 제34권4호
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• pp.490-492
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• 2007

Purpose: Nipple reconstruction is an important step in breast reconstruction after mastectomy. There are considerable number of reconstructive methods developed over the past years. Each of these has not only its own special advantages, but also limitations. Therefore, no single method has become the overwhelming favorite. Sometimes it seems to be compromised when the nipple must be located directly over a linear scar. Methods: A 48-year-old female patient received a central lumpectomy with circumareolar resection of the nipple areolar complex 4 months ago. The newly designed nipple must be positioned directly astride a scar. We drew two equal-sized rectangular flaps sharing a common limb on a transverse scar and the result was two opposing plow form. Each flap size was about 1.3 cm wide and 2.5 cm long. First we elevated the flap from the distal part at a deep dermal plane, then deepened the level of dissection to raise the dermal-fat flaps. The donor site could be closed directly without any dog-ear deformity. Then we folded down the elevated flaps and loosely sutured skin with nonabsorbable materials. Each flap inner side was approximated side by side. Finally we made new natural nipple with 6 mm projection. We applied tattooing in the areola area with micropigmentation device after three months. Results: After ten months of follow-up periods, the nipple projection was stable and symmetric. The nipple projection was 3.1 mm, compared with 2.8 mm for the opposite nipple. Conclusion: Our experiences shows that this double opposing plow flap is a particularly useful and simple technique when there is a traverse scar crossing the center of the proposed nipple area.

• Current Research on Agriculture and Life Sciences
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• 제2권
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• pp.42-55
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• 1984

The direction of scientific researches on tree improvement and forest management in several universities and research institutes in Japan can be summarized as follows: They put a great emphasis on sugi, Cryptomeria japonica and cypress, Chamaecyparus oblusa which are two major conifer species largerly planted in the Japanese forestry. In the research of sugi, a great concern has been made in evaluating inheritance of forest tree, quantitative characters and genetic parameter of growth, and in breeding for resistance to diseases and insects and to all the natural calamities. Interaction between environmental conditions and genetic nature of tree can be concerned factors in relation with forest damage, together with silvicultural conditions and pest infestation. Selfing hybrids of $F_1$ made from crossing twisted-leaf sugi, defomity leaf type and midori sugi, normal leaf type segregated the normal needle, twisted needle, green leaf and albino leaf type. It seemed that separation of many defomity individuals can be governed by two dominant complementary genes and from the near loci of which it was detected lethal genes. 52% of Japanese forestry is occupied by the small forest landowners like Korean forestry. This made difficulty for forest improvement such as progressive afforestation and for capital accumulation form forestry. The Forest Corporation was established at first in 1959 to aming at productive forestry structure and forest management, and afforestation. For these purpose, 35 Forest Corporations are at moment operating throughout Japan. However, investment in forestry business becomes less attractive since the wage in forest production duction increased in higher trend. than timber price. Therefore, an artifical afforestation becomes yearly decreased. At present. the self-sufficient rate of timber production in Japan is about 35%, and so a great effort is being made to increase self-sufficient rate of timber production.