• Title/Summary/Keyword: 시계방향

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The Present and Future of Research Industry in Korea (우리날 조사산업의 현황과 전망)

  • 박무익
    • Proceedings of the Korean Association for Survey Research Conference
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    • 2000.06a
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    • pp.161-177
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    • 2000
  • Research industry in Korea has shown remarkable development in the past decade, mainly owing to the fact that the confidence level on the research itself has been largely improved as the major predictions based on poll result hit the mark in the past presidential elections, and also the change of management style in Korean business based on the rational decision making process. In the article, I will analyze the change of Korean\\\\`s behavior toward public opinion research in diachronic manner and show the number and activities of Research Organizations in order to look into the present condition of research industry and then think about the future and the desirable direction of Korea research industry.

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Electrical characteristics of MOS capacitors with Ge nanocrystals embedded in high-k materials (고유전체 박막에 형성된 Ge 나노크리스탈을 이용한 MOS 커패시터의 전기적 특성)

  • Yun, Jeong-Gwon;Lee, Hye-Ryoung;Park, Byoung-Jun;Cho, Kyoung-Ah;Kim, Sang-Sig
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1351-1352
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    • 2007
  • $ZrO_2$$HfO_2$ 박막에 이온 주입을 거친 후 열처리 과정을 통해 Ge 나노입자를 형성시켜 MOS 커패시터를 제작하였다. C-V 곡선에서는 반시계 방향의 hysteresis가 관찰되었으며, $ZrO_2$ MOS 커패시터에서는 -9 V에서 9 V까지 전압변화를 주었을 때 3 V 정도의 메모리 윈도우가 나타남을 확인 할 수 있었다. 또한, $HfO_2$ MOS 커패시터에서는 -10 V에서 10 V까지 전압변화를 주었을 때 3.45 V의 메모리 윈도우를 관찰 할 수 있었다.

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A study for the characteristics of non-volatile ZnO nanowire memory using $Al_{2}O_{3}$ charge trapped layers ($Al_{2}O_{3}$ 전하포획층으로 이용한 ZnO 나노선 비휘발성 메모리의 특성에 관한 연구)

  • Keem, Ki-Hyun;Kang, Jeong-Min;Yoon, Chang-Joon;Yeom, Dong-Hyuk;Jeong, Dong-Young;Park, Byoung-Jun;Kim, Sang-Sig
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1279-1280
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    • 2007
  • $Al_{2}O_{3}$ 절연막을 전하포획층으로 이용하여 Top 게이트 ZnO 나노선 전계효과트랜지스터를 제작하였고, 메모리 효과를 관찰하였다. $Al_{2}O_{3}$ 층을 게이트 절연막과 전하포획층으로 사용하였다. 대표적인 Top 게이트 ZnO 나노선 전계효과트랜지스터에 대하여 게이트 전압을 Double sweep 하였을 때의 드레인 전류-게이트 전압 특성이 반시계 방향의 히스테리시스와 문턱전압변화를 나타냈다. 펄스 형태의 게이트 전압을 1초 동안 인가한 후에, 드레인 전류-게이트 전압 특성의 문턱전압 변화가 0.3 V에서 0.8 V로 증가하였다. 이러한 특성은 게이트 전극에서 음전하 캐리어가 음의 게이트 전압에 대하여 $Al_{2}O_{3}$ 층에 충전되고, 양의 게이트 전압에 대하여 방전되는 것을 나타낸다.

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Digestive Apparatus and Food of the Korean Bitterling, Acheilognathus signifer (Cyprinidae) (묵납자루, Acheilognathus signifer의 소화기관과 먹이생물)

  • Baek, Hyun-Min;Song, Ho-Bok
    • Korean Journal of Ichthyology
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    • v.17 no.1
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    • pp.57-63
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    • 2005
  • The digestive apparatus and food of the Korean bitterling, Acheilognathus signifer, from the upper reaches of the Hongcheon River were investigated by examining their gill rakers, pharyngeal teeth, and digestive-tube contents. Gill rakers of the first arch were relatively few (17 to 21, mean = 19) and short (mean = 0.36 mm, SD = 0.035). The 2nd to 5th pharyngeal teeth were well developed, while the first tooth was poorly developed. Gill rakers and pharyngeal teeth were completely formed early in life. The digestive tube was long and arranged in many coils. The digestive-tube contents of Korean bitterling mainly consisted of phytoplankton and detrital microorganisms.

Ultrastructures of Germ Cells Before and After Insemination in Rainbow Tront, Oncorhynchus mykiss (수정전후 무지개 송어 (Oncorhynchus mykiss)의 생식세포의 미세구조)

  • Yoon, Jong-Man;Park, Hong-Yang
    • Development and Reproduction
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    • v.4 no.1
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    • pp.1-6
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    • 2000
  • Ultrastructure of the zona radiata the micropyle and fertilization process in the rainbow trout (Oncorhynchus mykiss) were examined by light, scanning and transmission microscopes . The egg micropyle of rainbow trout consists of a funnel-shaped vestibule and a tapered canal transversing the zona radiata. The micropyle showed the type with a flat pit leading into a long canal and the micropylar wall showed the clockwise spiral structure. There were a great number of microvilli secreting adhesive materials having trapping function attracting the spermatozoa in the vicinity of micropyle. It was apparent that ridges extended between the projections. In the initial stages of penetration, the spermatozoon still within the micropylar canal attached perpendicularly at its apical tip to the egg surface, then the sperm head was rapidly engulfed by the folded egg surface with its many microvilli. The spermatozoon disappeared from the outer surface of the egg before the fertilization cone completely retracted 250 seconds after insemination. No interconnecting ridges was present in the egg surface. In short, the block to polyspermy to permit entry of a single sperm is considered to be mechanical by the morphological design of the micropyle and fertilization cone.

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Postpneumonectomy Syndrome after Left Pneumonectomy -one case report- (좌측 전폐절제술후 발생한 Postpneumonectomy Syndrome의 치험 1례)

  • 윤용한;이두연;김부연
    • Journal of Chest Surgery
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    • v.31 no.6
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    • pp.624-628
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    • 1998
  • Postpneumonectomy syndrome is a rare and delayed complication of left pneumonectomy in most patients with normal mediastinal vascular anatomy. This syndrome is characterized by dyspnea and recurrent pulmonary infection in the remaining right lung that typically occur within the first postoperative year. The condition is believed to be secondary to postsurgical changes that include a marked shift of the mediastinum to the left, clockwise rotation of the heart and great vessels, and herniation of the right lung into the left anterior thorax. These changes lead to compression of the trachea or right main bronchus among the thoracic spine and the right pulmonary artery. We report a case of postpneumonectomy syndrome in 15 year-old girl that followed by left pneumonectomy for bronchiectasis 6 years ago. We have inserted an expandable prosthesis in the left thoracic cavity posterior to the heart. After implantation of an expandable prosthesis, an anatomic reposition of the shifted mediastinum was achieved, which resulted in instantaneous and sustained relief. The post-operative course was uneventful and the patient was followed in OPD from after discharge to now.

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Granulite xenoliths in porphyroblastic gneiss from Mt. Jiri area, SW Sobaegsan massif, Korea (소백산육괴 서남부 지리산지역의 반상변정질 편마암에서 산출되는 백립암질 포획암)

    • The Journal of the Petrological Society of Korea
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    • v.8 no.1
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    • pp.34-45
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    • 1999
  • Mafic granulite xenoliths are found in precambrian porphyroblastic gneiss of the Mt. Jiri area, SW Sobaegsan massif, Korea. The xenoliths are rounded to ellipsoidal in shape, 50-100 cm in length and coarse-grained with granoblastic and foliated texture. The xenoliths consist of orthopyroxene, garnet, biotite, plagioclase, quartz, ilmenite and secondary orthoamphibole. Orthopyroxene is mostly resorbed and rimmed by coronitic orthoamphiboles. Garnets occur as porphyblasts and are zoned with higher pyrope content in cores than in rims. Geothermo-barometry results yield conditions of about $800-850^{\circ}C$, 6 kb and $500^{\circ}C$, 4 kb for early and retrograde stages of equilibration, respectively. According to available geochronological data, it is suggested that the granulite facies metamorphism occurred prior to 2.1-1.9Ga and that the area was superimposed by the high-grade (over $600-700^{\circ}C$) metamorphism between 1.9-1.7Ga, followed by cooling during uplift.

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Metamorphic Evolution of the Ogcheon Metamorphic Belt: Review of Recent Studies and Remaining Problems (중부 옥천변성대의 변성진화: 최근의 연구결과 논평 및 문제점)

  • 조문섭;김현철
    • The Journal of the Petrological Society of Korea
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    • v.11 no.3_4
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    • pp.121-137
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    • 2002
  • Metamorphic evolution of the Ogcheon metamorphic belt has been studied by many investigators for the past few decades. P-T conditions of the Ogcheon metamorphic belt were estimated as 4.2-9.4 kbar and $490-630^{\circ}C$, corresponding to the medium-pressure type. In addition, the clockwise P-T-t path suggests a crustal-thickening event in association with the formation of thrust nappes. However, some details on deformation and orogeny of the Ogcheon metamorphic belt have been ambiguous yet. Although the metamorphic age has been also equivocal, recent isotopic studies strongly suggest that the peak metamorphism in the Ogcheon metamorphic belt has occurred at ca. 300-280 Ma between Late Carboniferous and Early Permian. It is thus inferred that the Ogcheon metamorphic belt and the Taebaegsan basin have evolved as separate terranes and that both were sutured at ca. 250-220 Ma. These results are partly in contrast with those of previous workers and require a revised framework for tectonic evolution of the Ogcheon belt. In addition, it is likely that the Ogcheon belt is correlative with the Hida marginal belt and the Hida metamorphic belt.

The Relationship between Korean Construction Industry and GDP in Economic Development Process (한국경제성장과정의 건설산업과 GDP의 관계 분석)

  • Choi, Dal-Sik;Le, Hoai;Lee, Young-Dai
    • Korean Journal of Construction Engineering and Management
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    • v.14 no.6
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    • pp.70-77
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    • 2013
  • Construction industry is broadly agreed as one of the most important sectors of any economy around the world. In this paper, time series data of Korean construction industry and Korean economy are examined. The Bon's proposition will be inspected for Korean context using both cross-sectional and longitudinal analyses. The analysis of the longer than four decades national account statistic of the Korean macro economy verify Bon's proposition of an inverted U-shaped relationships. The verified U-shaped relationships for Korean context exist not only in terms of the construction share in total GDP but also in terms of total construction volume as an economy develops from LDC to NIC and then to AIC eventually with time. The results of the thesis show that the contribution towards the macro economy has varied across different stages of development.

Capacitance-Voltage Characterization of Ge-Nanocrystal-Embedded MOS Capacitors (Ge 나노입자가 형성된 MOS 캐패시터의 캐패시턴스와 전압 특성)

  • Park, Byoung-Jun;Choi, Sam-Jong;Cho, Kyoung-Ah;Kim, Sang-Sig
    • Journal of IKEEE
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    • v.10 no.2 s.19
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    • pp.156-160
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    • 2006
  • Capacitance versus voltage (C-V) curves of Ge-nanocrystal (NC)-embedded MOS capacitors with and without a single capping Al2O3 layer are characterized in this work. C-V curves of the Ge-NC-embedded MOS capacitor with the A12O3 layer are counterclockwise in the voltage sweeps, which indicates tile presence of charge storages in the Ge NCs by the tunnelling of charge carriers between the Si substrate and the Ge NCs. In the Ge-NC-embedded MOS capacitor without Al2O3 layer, clockwise hysteresis of the C-V curves and leftward shifts of the flat band voltages are observed for the embedded MOS capacitor without the Al2O3 layer. It is suggested that the characteristics of the C-V curves are due to the charge trapping at oxygen vacancies within a SiO2 layer. In addition, the illumination of the white light enhances the lower capacitance part of the C-V hysteresis. The origin for the enhancement is discussed in this paper.

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