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        검색결과 2,330

        1121.
        2013.11 구독 인증기관 무료, 개인회원 유료
        4,000원
        1124.
        2013.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Spherical Ti-6Al-4V powders in the size range of 250 and 300 µm were uniformly doped with nano-sized hydroxyapatite (HAp) powders by Spex milling process. A single pulse of 0.75-2.0 kJ/0.7 g of the Ti-6Al-4V powders doped with HAp from 300 mF capacitor was applied to produce fully porous and porous-surfaced Ti-6Al-4V implant compact by electro-discharge-sintering (EDS). The solid core was automatically formed in the center of the compact after discharge and porous layer consisted of particles connected in three dimensions by necks. The solid core increased with an increase in input energy. The compressive yield strength was in a range of 41 to 215 MPa and significantly depended on input energy. X-ray photoelectron spectroscopy and energy dispersive x-ray spectrometer were used to investigate the surface characteristics of the Ti-6Al-4V compact. Ti and O were the main constituents, with smaller amount of Ca and P. It was thus concluded that the porous-surfaced Ti-6Al-4V implant compacts doped with HAp can be efficiently produced by manipulating the milling and electro-discharge-sintering processes.
        4,000원
        1125.
        2013.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 논문에서는 Pebax-2533 판형 분리막을 1-프로판올과 n-부탄올 혼합용매를 이용하여 용해, 건조하여 제조하였고 time-lag 장치를 이용하여 CO2, N2 투과특성을 평가하였다. 제조된 분리막은 평가조건에 따라서 130-288 barrer의 CO2 투 과율을 가졌으며, CO2/N2 투과선택도는 5-8이었다. Time-lag 장치의 주입부 압력이 증가함에 따라서, 투과온도가 낮아짐에 따라서, 그리고 혼합용매의 n-부탄올 양이 증가함에 따라서 CO2 투과도는 감소하였다. 이러한 실험 자료는 Pebax-2533 분리 막의 CO2 투과율이 CO2 용해에 매우 의존할 것이라 예측과 달리, CO2 용해뿐만 아니라 CO2 확산도 매우 중요한 단계임을 의미하였다.
        4,000원
        1126.
        2013.10 구독 인증기관·개인회원 무료
        골유도재생술은 골결손부의 부피를 회복하기 위해 차폐막을 이용하는 치과수 술이다. 이 차폐막에는 동물유래의 콜라겐과 합성재료로서 polytetrafluoroethylene (PTFE)를 이용한 것이 개발되어 있다. 본 연구에서는 백서두정골에 인위적 결손부 를 형성하고 실크 차폐막의 골유도재생효과를 평가해보았다. 이를 위해 총 30마리 의 Sprague-Dawley 백서가 사용되었는데, 실크차폐막을 실험군으로, 콜라겐 차폐 막(Rapi-gideⓇ)과 PTFE(cytoplastⓇ)을 대조군으로하여 각각 10마리씩 적용하였 다. 백서 두정골에 하나의 골 결손부를 형성한 후, 차폐막을 덮고 4주, 8주에 희생시 켜서 방사선학적 방법(μ-CT)으로 골생성정도를 비교해보았다. 결과, 수술 4주후 에는 실크(13.58mm 3 )와 콜라겐(7.06mm 3 ), PTFE(1.86mm 3 )대조군사이에 큰 차이 가 있었다(p <0.05). 수술 8주 후에는 각 군 사이에 큰 차이는 없었다(p >0.05). 하지 만 실크 차폐막 적용군에서는 다른 대조군들과는 달리 이물질 반응이 거의 없는 조 직학적 소견이 관찰 되었다. 결론적으로, 이 실험에서, 실크차폐막이 골유도재생술 을 위한 재료로써 유효함을 알 수 있었다.
        1127.
        2013.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        남자고등학교 교실에서 발생하는 냄새(발냄새, 머리냄새, 쉰냄새, 땀냄새)와 대표악취물질(부티르산, 암모니아)에 대한 뇌파반응을 분석하였다. 냄새자극 시험은 30~50대의 여성을 대상으로 수행하였다. 교실냄새와 대표악취물질의 자극에 대한 뇌파 지표들의 변화 경향은 측두엽에서 가장 두드러지게 나타났다. 이들 악취물질의 측두엽에서 반응은 바탕뇌파대비 상대알파파를 0.04~0.13 감소시켰고, 상대베타파 0.02~0.06, 상대감마파를 0.03~0.09 증가시켰다. 교실냄새들과 두 악취물질들은 이완상태를 나타내는 알파파를 감소시켰고, 각성과 긴장 및 스트레스를 나타내는 고베타파(18~30Hz)와 불안과 흥분상태를 나타내는 감마파(30~50Hz)를 활성화시켰다. 냄새물질들의 뇌 각성 및 자극정도는 머리냄새 > 부트르산 > 발냄새, 쉰냄새 > 암모니아> 땀냄새 순이었다. 이러한 결과는 교실냄새가 과도한 각성이나 긴장을 유발하므로 수업 집중력이나 학습능력을 저해할 수 있음을 의미한다.
        4,000원
        1128.
        2013.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cryopreservation of epididymal spermatozoa offers a potential tool for rescuing genetic material from males of genetically elite populations. Castration, catastrophic injury, sudden death or any other event that makes semen collection or mating impossible may prematurely terminate a stallion reproduction. Stallion epididymal spermatozoa vary widely in the loss of progressive motility, acrosomal integrity, and viability during freezing and thawing. The objective of this work was to investigate the effect of (1) freezing package types on cryopreservation efficiency, (2) thawing temperatures (37, 56 or 70℃) on Computer Assisted Sperm Analysis (CASA) parameters and (3) post-thawing incubation time (0, 1, 2 or 4h) on castrated stallion epididymis. Post-thawed sperm motility ranged between 59.69% and 64.28% (56℃ and 37℃) in various thawing temperatures. When stallion epididymis sperm was frozen, straw was better than freezing tube on VCL (Velocity of Curvilinear Line) and VAP (Velocity of Average Path) parameter. Higher percentage of motility was observed at 37℃ thawing temperature even though no significant difference was observed among various temperatures. The motility, VCL, ALH (Amplitude of Lateral Head displacement), VAP, BCF (Beat-Cross Frequency) and STR (Straightness index) parameter of post-thawed sperm were significantly decreased by increasing the incubation time for all thawing temperatures. The present study showed that type of freezing package (Straw vs. Freezing tube) was not significantly different on cryopreservation efficiency. Furthermore, stallion epididymal spermatozoa frozen-thawed at 37℃ for 1 min resulted the highest proportion of motility and velocity movement. In addition, motility and viability of frozen-thawed stallion epididymal spermatozoa were also decreased by incubation.
        8,400원
        1129.
        2013.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        목 적: 크로마젠 렌즈의 색상별 시감투과율과 색상에 따른 근거리 시력과 선명도를 측정하여 비교 연구하기 위함이다. 방 법: 8가지 색상을 가진 크로마젠 렌즈의 분광투과율을 Shimadzu사의 UV-VIS Spectrophotometer(UV-2450)를 사용하여 측정한 후 380~780nm의 가시광선 전 영역에 대한 시감투과율을 구하였다. 대전 소재 K대학교 대학생 중에서 원거리 양안 교정시력이 1.0이상이 나오는 학생 총 30명 대상으로 800lux의 조명에서 40cm 근거리용 스넬렌 E시표를 이용하여 색상별 근거리 시력을 측정하고 가장 선명도가 좋은 색상과 가장 선명도가 떨어지는 색상을 선택하여 색상별 분포를 알아보았다. 결 과: 시감투과율은 Yellow 69.9%, Blue 69.1%, Violet 68.4%, Pink 63.5%, Aqua Blue 63.2%, Orange 61.5%, Magenta 52.2%, Green 46.2% 로 나타났다. 크로마젠 렌즈를 착용한 상태에서 Yellow와 Blue에서 가장 높은 시력이 측정되었고, Green과 Magenta에서 가장 낮은 시력이 측정되었다. 선명도가 가장 높은 색상으로는 Blue(30%)가 가장 많이 선택되었고, 선명도가 가장 낮은 색상으로는 Magenta(26.7%)로 많이 선택되었다. 결 론: 시감투과율이 높은 색상일수록 근거리 시력과 선명도가 우수하였다. 따라서 렌즈의 색상 선택 시시감투과율이 시력에 미치는 영향을 반드시 고려해야 할 것이다. 색상의 비교 분석에 따라 적절한 색상을 선택해야 한다.
        4,000원
        1130.
        2013.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        생육에 가장 알맞은 상대습도조건 구명을 위하여관례적으로 사용하는 조건을 기준으로 고정식과 생육시기별로 상대습도조건을 달리하는 가변식으로 설정하여 자실체의 특징을 조사하였다. 고정적인 상대습도가 수확율과 수확기간에 미치는 영향은 방임과솎음 공히 상대습도가 낮을수록 발이소요일이 길어졌고, 수학소요일도 같은 경향을 보였다. 고정식 상대습도의 방임처리구에서의 상대습도의 영향은 70,80, 90%일때 품질은 각각 5.5, 5.8, 6.3로 90%가 가장 우수하였다. 무게에 있어서는 90% 처리에서 병당98.6g으로 가장 수량이 많았다. 솎음처리구에서 품질은 솎음처리구와 마찬가지 경향으로 상대습도가70, 80, 90%일때 각각 7.7, 8.4, 8.5로 90% 처리가가장 우수하였고, 수확량에서도 90%의 상대습도 처리가 병당 116.9g으로 우수하였다. 생육시기별 상대습도를 달리 적용하여 솎기 처리를 하였을 경우, 조건Ⅰ 90%이상 1일 → 85% 균솎기전(11일정도)→80%로 관리하는 조건 I과 90%이상 발이직전(7일정도) → 85% 균솎기전(5일정도) → 80%로 관리하는조건 Ⅲ의 병당 수확량이 85.5와 87.8g이며, 품질도7.8과 8.0으로 우수하였다. 이에 상대습도조절 조건 I과 III을 농가현장에 맞게 선택하여 적용하기를 제안한다.
        4,000원
        1131.
        2013.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Recently, there has been an increasing interest in the keyword, emotion, in many areas including information technology. Previous research mostly used emotion as the input of the contents or to present the changing contents based on the user's emotional states. In this research, a new platform that allows sharing each other's emotional state and a couple of prototype contents utilizing the platforms are developed. There are two different ways to build such emotion sharing platforms either sharing the emotional states in real-time or not. We used stateless server for the asynchronous emotion sharing, while stateful server is utilized for the real-time emotion sharing. This paper explains the systems architecture of both stateful and stateless servers and describes the prototype applications. Content developers should be able to utilize the platforms developed in this paper.
        4,000원
        1133.
        2013.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        For providing a basic data concerning with a fishing deck layout design of a trawler the authors conducted the video observations about the working activities of crews on the deck in the different layout of two Korean coastal large stern trawlers (gross tonnage: 139). The winch of the trawler-A was installed on the aft of the fishing deck and the trawler-B, on the forward of the fishing deck. The work and activities of the deck hands on both trawlers were observed using the CCD (charge coupled device) camera installed on each trawler's deck for one month from August 3, 2010. The video data was analyzed by the hierarchical task analysis (HTA) method. In results, numbers of tasks to require deck hands during the hauling net and the casting net were 25 and 28 for the trawler-A and 27 and 48 for the trawler-B, respectively. The working processes were represented a same in both of the trawlers. Location for controlling the deck machineries, the location installed trawl winch, kinds of deck machineries, crew's custom for using deck machineries were the factor affecting to the number of the task. In the case of the improvement suggested in the results is carried out, the reduction percentages of the number of task in the trawler-A and trawler-B were estimated as 24.5% and 51.3%, respectively. Through this study it was found that the quantitative analysis is possible for the work processes, work methods and the work contents in the trawler. Also the suggestion for improving the fishing deck layout design of the trawler was possible by finding out the factors increasing the number of tasks and removing the tasks. We expect that the results of this paper are used as a basic data for designing the layout of deck machineries in the trawler in the future.
        4,900원
        1134.
        2013.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To suggest a standard concerning with the arrangement of bridge equipment, the authors conducted the video observations with 3CCD (charge coupled device) cameras installed on the ceil of the bridge for monitoring the working activities of two bridge teams (the skipper/mate1 and the skipper/mate2) in a Korean coastal large trawler(gross tonnage: 139) for five days from July 30th. 2010 and analyzed of the data. Work elements coded by the work activities were input on the sheet of work analysis by the time unit of 1 sec according to the time occurred. A single work element among the work activities for every 5 minutes was denoted as the number of occurrence. The frequency of equipment usage was limited only in the usage of the equipment. In the case of the navigation and the towing net two ranks were integrated and analyzed. On the other hand, in the case of the casting net and the hauling net, two processes were integrated to as one and then analyzed separately as two ranks. As the results, 15 elements of work was carried out between two bridge teams for the observation; lookout, radar, GPS plotter, fish finder, net monitor, fishing deck, RPM indicator, rudder angle indicator, compass card, for maneuver; steering, ship speed control, trawl winch operation and external communications, paper works and others. It was found that the work load of the skipper per 5 minutes accordance with the navigation, the casting net, the towing net and the hauling net are 20.5 times, 11.9 times, 38.0 times and 9.5 times respectively, the mates are 65.2 times, 66.5 times, 85.7 times and 59.1 times respectively. The radar was shown the highest frequency of the equipment usage and the next was the fish finder, the GPS plotter and the external communications in the case of the navigation. In the case of the towing net the frequency of usage was high the ranking as the radar, the net monitor, the fish finder, the GPS plotter, the steering system and the external communications. In the case of the integrated process both of the casting and hauling net the trawl winch was shown the highest frequency to the skipper and the next was the GPS plotter and the radar, and the steering system was shown the highest frequency to the mate and the next was the radar, the ship speed control system, the GPS plotter, the net monitor and the fish finder.
        4,000원
        1135.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        4,000원
        1136.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study proposed proposes a retrofitting method using an H‐beam frame to improve the seismic performance of non‐seismic designed reinforced concrete frames. To evaluate the seismic performance with the H‐beam frames, a cyclic lateral load test was performed and the experimental result was compared with the bared frame, and a masonry infilled RC frame. The results was were analyzed regarding aspects of the load‐displacement hysteresis behavior, effective stiffness, displacement ductility, and cumulative energy dissipation. AlsoIn addition, it was possible to prove both an increase of in the maximum load capacity, effective stiffness, and energy dissipation capacity using the H‐beam frame.
        4,000원
        1137.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        When developing a product, ensuring the quality and reliability is essential. Reliability process is always underestimated compared to its importance, especially in the field of domestic medical devices. In this paper, reliability process developed for near-infrared solid microscope, based on a variety of existing practices and other product process. The following findings were obtained as research progressed. First, learning about the medical equipment needed to assure the quality and reliability standards. Second, reliability process established to design a product in the field of medical devices
        4,000원
        1140.
        2013.05 구독 인증기관 무료, 개인회원 유료
        The wooden buildings covered with tile-roofing and straw-thatched consist of Hahoe village, and so lower fire safety is concerned about. So, the purpose of this study is to introduce the fire spread simulation result of Haheo village and to analyze the actual situation of the disaster mitigation for protecting this village. The results of this study are as follows. First, the development of fire-fighting training and disaster mitigation facilities suitable for the elderly person is necessary. Second, it is important to consider securing of fire-fighting water which is usable in daily life and to popularize fire alarms to perform initial fire extinguishing effectively. Third, fire engines suitable for road width are changed from a conventional pump car, fire-fighting become smoothly. Finally, it is necessary to warn not only inhabitants but also the tourist about the handling of the fire.
        4,000원