검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 109

        41.
        2015.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Fe-base superalloy powders with Y2O3 dispersion were prepared by high energy ball milling, followed by sparkplasma sintering for consolidation. High-purity elemental powders with different Fe powder sizes of 24 and 50mm were usedfor the preparation of Fe-20Cr-4.5Al-0.5Ti-O.5Y2O3 powder mixtures (wt%). The milling process of the powders was carriedout in a horizontal rotary ball mill using a stainless steel vial and balls. The milling times of 1 to 5 h by constant operation(350 rpm, ball-to-powder ratio of 30:1 in weight) or cycle operation (1300 rpm for 4 min and 900 rpm for 1 min, 15:1) wereapplied. Microstructural observation revealed that the crystalline size of Fe decreased with an increase in milling time by cyclicoperation and was about 15nm after 3 h, forming a FeCr alloy phase. The cyclic operation had an advantage over constantmilling in that a smaller-agglomerated structure was obtained. The milled powders were sintered at 1100oC for 30 min invacuum. With an increase in milling time, the sintered specimen showed a more homogeneous microstructure. In addition, ahomogenous distribution of Y-compound particles in the grain boundary was confirmed by EDX analysis.
        4,000원
        43.
        2014.11 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        In this research, magnesium powder was prepared by gas atomizing. Refinement behaviors of magnesium powder produced under different conditions were investigated using a mechanical milling (attrition milling) process. Analyses were performed to assess the characterization and comparison of milled powder with different steel ball sizes and milling times. The powders were analyzed by field emission scanning electron microscope, apparent density and powder fluidity. The particle morphology of the Mg powders changed from spherical particles of feed metals to irregular oval particles, then plate type particles, with an increasing milling time. Because of the HCP structure, deformation occurs due to the existence of the easily breakable C-axis perpendicular to the base, which results in producing plate-type powders. An increase in ball size and the impact energy of the magnesium powder maximizes the effect of refinement. Furthermore, it is possible to improve the apparent density and fluidity according to the smoothness of the surface of the initial powder.
        4,000원
        44.
        2014.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Stroke incidence is increasing accordance with the aging of the population. While stroke patients increases the survival rate due to the contemporary development of medicine, goes on increasing the chronic disease by muscle impairment called hemiplegia. Rehabilitation training of motor skills for hemiplegia patients comprises repetitive and passive contents. In this paper, we developed a movement recognition device using acceleration sensor to help the upper limb rehabilitation and functional game contents in order to reduce the boredom of rehabilitation. By this contents, we can be maximized effect of the exercise using rehabilitation training contents made by simple graphical resources and added fun. Later on, we will provide various contents that can use several platform interface and can be have a lot of fun exercise and spread the range of applications of functional game contents.
        4,000원
        45.
        2013.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We examined various ball-milling parameters which affect the structural and morphological modification of multi-wall carbon nanotubes. In particular, the effect of milling mode and the use of different milling agents were exam- ined. Friction milling mode induced more structural changes than impact milling mode except the use of dry ice as a milling agent. Wet milling was helpful for reducing more effectively the agglomeration of nanotubes than dry milling. The use of hard solid particles such as silica and alumina as milling agents resulted in an effective shortening of nan- otubes, but often susceptible to the amorphization and the destruction of crystallinity.
        4,000원
        46.
        2013.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        경남농업기술원 화훼연구소에서 백색 소륜계의 ‘White Time’ 을 모본, 황색 중륜계의 ‘01-142-41’을 부본으로 인공교배를 실 시하여 계통 육성 후, 2006년부터 2008년까지 특성검정을 실시 한 결과 화색, 화형, 수확량 등 품질과 수량이 우수하다고 판단 되어 2008년 농작물 직무육성 신품종선정위원회의 심의를 거쳐 ‘Ice Ball’로 명명 품종등록(품종보호 제3736호) 하였다. ‘Ice Ball’은 백색(RHS 155-C)과 녹색(RHS 149-B)의 화심색 조화 가 선명한 반겹꽃 소륜화이다. 또한 ‘Ice Ball’은 화형이 안정되 고 화경이 강건하며 주당 연간 평균수량은 3회 검정 결과 평균 111.3개이며, 평균 절화수명은 13.8일이다.
        3,000원
        47.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        After liberation from Japanese colonial rule in 1945, there was the three-year period of United States Army Military Government in Korea. In 1948, Democratic People’s Republic of Korea, and Republic of Korea were established in the north and south of the Korean Peninsula. The Republic of Korea is now a modern state set in the southern part of the Korean. We usually refer to Koreans as people who belong to the Republic of Korea. Can we say that is true exactly? Why make of this an obsolete question? The period from 1945 when Korea was emancipated from Japanese colonial rule to 1948 when the Republic of Korea was established has not been a focus of modern Korean history. This three years remains empty in Korean history and makes the concept of ‘Korean’we usually consider ambiguous, and prompts careful attention to the silence of ‘some Koreans’forced to live against their will in the blurred boundaries between nation and people. This dissertation regards ‘Koreans’who came to live in the border of nations, especially ‘Korean-Japanese third generation women artists’ who are marginalized both Japan and Korea. It questions the category of ‘Korean women’s art’that has so far been considered, based on the concept of territory, and presents a new perspective for viewing ‘Korean women’s art’. Almost no study on Korean-Japanese women’s art has been conducted, based on research on Korean diaspora, and no systematic historical records exist. Even data-collection is limited due to the political situation of South and North in confrontation. Representation of the Mother Country on the Artworks by First and Second-Generation Korean-Japanese(Zainich) Women Artists after Liberation since 1945 was published in 2011 is the only dissertation in which Korean-Japanese women artists, and early artistic activities. That research is based on press releases and interviews obtained through Japan. This thesis concentrates on the world of Korean-Japanese third generation women artists such as Kim Jung-sook, Kim Ae-soon, and Han Sung-nam, permanent residents in Japan who still have Korean nationality. The three Korean-Japanese third generation women artists whose art world is reviewed in this thesis would like to reveal their voices as minorities in Japan and Korea, resisting power and the universal concepts of nation, people and identity. Questioning the general notions of ‘Korean women’and ‘Korean women’s art’ considered within the Korean Peninsula, they explore their identity as Korean women outside the Korean territory from a post-territorial perspective and have a new understanding of the minority’s diversity and difference through their eyes as marginal women living outside the mainstream of Korean and Japanese society. This is associated with recent post-colonial critical viewpoints reconsidering myths of universalism and transcendental aesthetic measures. In the 1980s and 1990s art museums and galleries in New York tried a critical shift in aesthetic discourse on contemporary art history, analyzed how power relationships among such elements as gender, sexuality, race, nationalism. Ghost of Ethnicity: Rethinking Art Discourses of the 1940s and 1980s by Lisa Bloom is an obvious presentation about the post-colonial discourse. Lisa Bloom rethinks the diversity of race, ethnicity, sexuality, and gender each artist and critic has, she began a new discussion on artists who were anti-establishment artists alienated by mainstream society. As migration rapidly increased through globalism lead by the United States the aspects of diaspora experience emerges as critical issues in interpreting contemporary culture. As a new concept of art with hybrid cultural backgrounds exists, each artist’s cultural identity and specificity should be viewed and interpreted in a sociopolitical context. A criticism started considering the distinct characteristics of each individual’s historical experience and cultural identity, and paying attention to experience of the third world artist, especially women artists, confronting the power of modernist discourses from a perspective of the white male subject. Considering recent international contemporary art, the Korean-Japanese third generation women artists who clarify their cultural identity as minority living in the border between Korea and Japan may present a new direction for contemporary Korean art. Their art world derives from their diaspora experience on colonial trauma historically. Their works made us to see that it is also associated with post-colonial critical perspective in the recent contemporary art stream. And it reminds us of rethinking the diversity of the minority living outside mainstream society. Thus, this should be considered as one of the features in the context of Korean women’s art.
        8,100원
        48.
        2012.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Nanocrystalline powder could be synthesized by solid-state reaction using the mixture which was prepared by a high energy milling process in a bead mill for and nanocrystalline powders mixture. Effect of the milling time on the powder characteristic of the synthesized powder was investigated. Nanocrystalline with a particle size of 50 nm was obtained at . High tetragonal powder with a tetragonality(=c/a) of 1.009 and a specific surface area of was acquired after heat-treatment at for 2 h. High energy ball milling was effective in decreasing the reaction temperature and increasing the tetragonality.
        4,000원
        49.
        2012.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, a high energy ball milling process was employed in order to improve the densification of direct nitrided AlN powder. The densification behavior and the sintered microstructure of the milled AlN powder were investigated. Mixture of AlN powder doped with 5 wt.% as a sintering additive was pulverized and dispersed up to 50 min in a bead mill with very small beads. Ultrafine AlN powder with a particle size of 600 nm and a specific surface area of 9.54 was prepared after milling for 50 min. The milled powders were pressureless-sintered at for 4 h under atmosphere. This powder showed excellent sinterability leading to full densification after sintering at for 4 h. However, the sintered microstructure revealed that the fraction of yitttium aluminate increased with milling time and sintering temperature and the newly-secondary phase of ZrN was observed due to the reaction of AlN with the impurity.
        4,000원
        50.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to evaluate the effects of bridging stabilization exercise on balance ability and gait performance in elderly women. The subjects of this study were thirty-one elderly women over 65 years old in HongSung-Gun Senior Citizen Welfare Hall. The subjects were randomly assigned into one of three groups (trunk stabilization exercise on the mat, whole body vibration, and Swiss ball) and participated in each exercise program three times a week for 4 weeks. Each exercise began in the bridging position. The dynamic balance and gait were measured by limit of stability area using force plate, Berg Balance Scale (BBS), and Timed Up and Go Test (TUG). The results were as follows: 1) The limit of stability in three groups increased significantly in anterior-posterior and medial-lateral lean after 4-weeks intervention (p<.05). 2) There were no significant differences in the limit of stability among three groups after 4-weeks intervention (p>.05). 3) The BBS and TUG in three groups increased significantly after 4-weeks intervention (p<.05). 4) There were significant differences among three groups in BBS. Post-hoc test showed that Swiss ball exercise group was significantly higher than the mat and whole body vibration groups. 5) There were no significant differences TUG among three groups after 4-weeks intervention (p>.05). In conclusion, this study suggested that 4 weeks of the bridging stabilization exercises were effective on balance and gait in all three groups. Particularly Swiss ball exercise group showed higher improvement than two other exercise groups (mat, whole body vibration group).
        4,000원
        51.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The effects of an abdominal drawing-in maneuver (ADIM) using a pressure bio-feedback unit (PBFU) were compared to the effects of a pelvic belt (PB) on the muscle activities of the hip and back extensor muscles during hip extension in the prone position. Fifteen healthy male participants all performed prone hip extensions under three conditions: 1) preferred hip extension (PHE), 2) performing an ADIM, and 3) using a PB. The muscle activities of the erector spinae, the gluteus maximus, and the medial hamstring on the right side were recorded by surface electromyography. The muscle activity of the erector spinae was significantly lower while performing an ADIM during prone hip extension than during PHE or with a PB (p<.05). Gluteus maximus muscle activity was significantly higher while performing an ADIM (p<.05). No significant difference was found for the medial hamstring muscle among the three conditions (p>.05). We concluded that the internal stabilization of the pelvis and lumbar spine afforded by the ADIM using a PBFU could be more effective than the external stabilization provided by a PB in terms of increasing selectively gluteus maximus activation during prone hip extension.
        4,000원
        52.
        2011.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Dry CVT(Continuously variable transmission) consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange of the driving pulley has the centrifugal roller and a ramp plate in the flange. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. The main advantages of the Dry CVT with V-belt, which has been popular in Asia, are a simple mechanism, less maintenance and low cost. The important claim which have an influence on the performance of the Dry CVT is the wear of the centrifugal roller. In this study ball type is proposed instead of roller type of movable flange to resolve claim. Also experiments are carried out for new model to evaluate performances.
        4,000원
        53.
        2011.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In order to make a (CZTSe) sputtering target sintered for solar cell application, synthesis of CZTSe compound by solid state reaction of Cu, Zn, Sn and Se mixed powders and effects of ball milling condition on sinterability such as ball size, combination of ball size, ball milling time and sintering temperature, was investigated. As a result of this research, sintering at after ball milling using mixed balls of 1 mm and 3 mm for 72 hours was the optimum condition to synthesis near stoichiometric composition of and to prepare sintered pellet with high density relatively.
        4,000원
        54.
        2010.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        1999, 2002년에 인공교배한 조합에서 선발된 계통들을 2004년부터 2006년까지 특성검정을 거쳐 최종 육성한 분화장미 신품종 ‘타이니볼’은 백/분홍 복합색의 왜성형 분화장미로 대비품종에 비해 꽃크기는 작은 편이나 꽃 잎수와 착화수가 많으며, 수고가 낮아 왜화제 처리 없 이도 상품화율이 높다.
        3,000원
        55.
        2010.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Sm-16.7wt%Co alloy powders were prepared by high energy ball milling under the conditions of various milling time and the content of process control agent (PCA), and their microstructure and magnetic properties were investigated to establish optimum processing conditions. The initial powders employed showed irregular shape and had a size ranging from 5 to . After milling for 5 h, the shape of powders changed to round shape and their mean powder size was approximately , which consisted of the agglomerated nano-sized particles with 15 nm in diameter. The coercivity was reduced with increasing the milling time, whereas the saturation magnetization increased. As the content of PCA increased, the powder size minutely decreased to approximately at the PCA content of 10 wt%. The XRD patterns showed that the main diffraction peaks disappeared apparently after milling, indicating the formation of amorphous structure. The measured values of coercivity were almost unchanged with increasing the content of PCA.
        4,000원
        56.
        2010.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        절화용 스프레이국화 ‘화이트볼’은 백색의 아네모네 화형인 ‘스텔리온’을 모본으로 하고 분홍색의 아네모네 화형인 ‘향로’를 부본으로 하여 2003년 10월에 교배를 하여 얻은 계통으로부터 선발하였다. 2005년부터 3년간 촉성재배, 자연재배, 억제재배 등 특성검정을 실시하였다. ‘화이트볼’은 백색의 아네모네 화형으로 10월 중순에 자연개화하는 중생 추국으로 자연재배시 본당 착화수는 16.2개이며, 꽃의 직경은 3.6cm이다. 촉성재배시 개화 소요일수는 58.5일이었고, 본당 착화수는 11.9개였다. 억제재배시의 개화소요일수는 54일이었다.
        4,000원
        57.
        2009.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Fe based (FeCSiBPCrMoAl) amorphous powder, which is a composition of iron blast cast slag, were produced by a gas atomization process, and sequently mixed with ductile Cu powder by a mechanical ball milling process. The Fe-based amorphous powders and the Fe-Cu composite powders were compacted by a spark plasma sintering (SPS) process. Densification of the Fe amorphous-Cu composited powders by spark plasma sintering of was occurred through a plastic deformation of the each amorphous powder and Cu phase. The SPS samples milled by AGO-2 under 500 rpm had the best homogeneity of Cu phase and showed the smallest Cu pool size. Micro-Vickers hardness of the as-SPSed specimens was changed with the milling processes.
        4,000원
        58.
        2009.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Fe based (FeCSiBPCrMoAl) amorphous powder, which is a composition of iron blast cast slag, were produced by a gas atomization process, and sequently mixed with ductile Cu powder by a mechanical ball milling process. The experiment results show that the as-prepared Fe amorphous powders less than 90 m in size has a fully amorphous phase and its weight fraction was about 73.7%. The as-atomized amorphous Fe powders had a complete spherical shape with very clean surface. Differential scanning calorimetric results of the as-atomized Fe powders less than 90 m showed that the glass transition, T, onset crystallization, T, and super-cooled liquid range T=T-T were 512, 548 and 36, respectively. Fe amorphous powders were mixed and deformed well with 10 wt.% Cu by using AGO-2 high energy ball mill under 500 rpm.
        4,000원
        59.
        2009.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A composite of rapidly solidified Al-6061 alloy powder with graphite particle reinforcements was prepared by ball milling and subsequent hot extrusion. The microstructure and mechanical properties of these composites were investigated as a function of milling time. With increasing milling time, the gas atomized initially and spherical powders became elongated with a maximum aspect ratio after milling for 30 h. Then, refinement and spheroidization were achieved by further milling to 70 h with a homogeneous and fine dispersion of graphite particles forming between the matrix alloy layers. The best compression and wear properties were obtained in the powder milled for 70 h, associated with the increased fine and homogeneous distribution of graphite particles in the aluminum alloy matrix.
        4,000원
        60.
        2008.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This paper deals with the phase analysis of bulk using spark plasma sintering process after ball milling. Mg and amorphous B powders were used as raw materials, and milled by planetary-mill for 9 hours at argon atmosphere. In order to confirm formation of phase, DTA and XRD were used. The milled powders were fabricated to bulk at the various temperatures by Spark Plasma Sintering. The fabricated bulk was evaluated with XRD, EDS, FE-SEM and PPMS. In the DTA result, reaction on formation of phase started at . This means that ball milling process improves reactivity on formation of phase. The MgO and FeB phases were characterized from XRD result. MgO and FeB were undesirable phases which affect formation of phase, and it's distribution could be confirmed from EDS mapping result. Spark Plasma Sintered sample for 5 min at was relatively densified and it's density and transition temperature showing super conducting property were and 21K.
        4,000원
        1 2 3 4 5