• 제목/요약/키워드: phi-features

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증착방법에 따른 Al 피막의 증착율 및 증기분포에 관한 연구 (Study on the deposition rate and vapor distribution of Al films prepared by vacuum evaporation and arc-induced ion plating)

  • 정재인;정우철;손영호;이득진;박성렬
    • 한국진공학회지
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    • 제9권3호
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    • pp.207-215
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    • 2000
  • 진공증착 및 이온플레이팅 방법을 이용하여 냉간 압연된 강판상에 알루미늄피막을 형성시킨 후, 증발율 및 증기분포 변화를 측정하고 각 증착방법에서의 증발율에 따른 증기분포 변화를 비교 및 검토하였다. 본 실험에서의 이온플레이팅은 증발원 근처에 이온화 전극을 설치하는 방법으로 고전류 아크방전을 유도하여 $10^{-4}$ Torr 이하에서도 기존의 이온플레이팅에 비해 높은 이온화율을 얻을 수 있는 아크방전 유도형 이온플레이팅(Arc-induced ion Plating; AIIP) 방법을 이용하였다. 전자빔을 이용하면서 알루미나 크루시블을 사용하여 알루미늄을 증발시킬 경우 분당 2.0 $\mu\textrm{m}$이상의 높은 증발율을 얻을 수 있었으며, 이온플레이팅의 경우 이온화된 증기의 상호작용에 따른 산란 효과로 증발율이 다소 낮아짐을 알 수 있었다. $cos^{n/\phi}$로 이루어지는 증기분포의 결정인자(n)의 값이 진공증착의 경우는 1에 근접하는 것으로 나타났고 AIIP의 경우는 2 또는 그보다 더 큰 값으로 이루어지는 것을 확인하였다. 이로부터 이온플레이팅의 경우 이온화율 또는 기판 바이어스 전압의 효과가 다른 조건에 비해 증기분포에 더 크게 영향을 미치는 것을 확인할 수 있었다.

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바이트코드를 위한 정적 단일 배정문 기반의 정적 타입 추론 (Static Type Inference Based on Static Single Assignment for Bytecode)

  • 김지민;김기태;김제민;유원희
    • 한국컴퓨터정보학회논문지
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    • 제11권4호
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    • pp.87-96
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    • 2006
  • 바이트코드는 많은 장점을 가지고 있으나 수행 속도가 느리고 프로그램의 분석과 최적화에 알맞은 표현은 아니다. 분석과 최적화를 위하여 바이트코드를 정적 단일 배정문(SSA Form)으로 변환이 수행되어야 한다. 그러나 바이트코드에서 SSA Form으로 변환 시 어떤 변수는 타입 정보를 상실한다. 이를 해결하기 위하여 본 논문에서는 바이트코드에 대한 확장된 제어 흐름 그래프를 생성한다. 또한 정적으로 분석하기 위해 제어 흐름 그래프를 SSA Form으로 변환한다. SSA Form으로 변환을 위하여 지배자. 직접 지배자. 지배자 경계. ${\phi}$-함수, 재명명 등 많은 정보에 대한 계산을 수행한다. 생성된 SSA Form에 알맞은 타입을 선언하기 위해서 다음과 같은 동작들을 수행한다. 먼저 클래스의 호출그래프와 상속 그래프를 생성한다. 그리고 각 노드에 대한 정보를 수집한다. 수집된 정보를 기반으로 동등한 타입의 노드를 찾고 강 결합 요소로 설정한 후 각 노드에 타입을 효율적으로 설정하는 방법을 제안하였다.

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Effect of GeO2 on embryo development and photosynthesis in Fucus vesiculosus (Phaeophyceae)

  • Tarakhovskaya, Elena R.;Kang, Eun-Ju;Kim, Kwang-Young;Garbary, David J.
    • ALGAE
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    • 제27권2호
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    • pp.125-134
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    • 2012
  • Germanium dioxide ($GeO_2$) has been used for many years in the cultivation of red and green algae as a means of controlling the growth of diatoms. Brown algae are sensitive to $GeO_2$, however, the basis of this sensitivity has not been characterized. Here we use embryos of $Fucus$ $vesiculosus$ to investigate morphological and physiological impacts of $GeO_2$ toxicity. Morphometric features of embryos were measured microscopically, and physiological features were determined using pulse amplitude modulated (PAM) fluorometry. At 5 mg $L^{-1}$ $GeO_2$, embryos grew slower than controls and developed growth abnormalities. After 24 h, initial zygote divisions were often oblique rather than transverse. Rhizoids had inflated tips in $GeO_2$ and were less branched, and apical hairs were deformed, with irregularly aligned, spheroidal cells. Minimum fluorescence ($F_0$) showed minor differences over the 10 days experiment, and pigment levels (chlorophylls $a$, $c$ and total carotenoids) showed no difference after 10 days. Optimum quantum yield increased from ca. 0.52 at 24 h to 0.67 at 5 days, and $GeO_2$-treated embryos had higher mean values (significant at 3 and 5 days). Optimum quantum yield of photosystem II (${\Phi}_{PSII}$) was stable in control thalli after 5 days, but declined significantly in $GeO_2$. Addition of silica (as $SiO_2$) did not reverse the effects of $GeO_2$. These results suggest that $GeO_2$ toxicity in brown algae is associated with negative impacts at the cytological level rather than metabolic impacts associated with photosynthesis.

마산만과 가덕수로 표층퇴적물의 중금속 원소와 저서성 유공충 특성 (Characteristics of Heavy Metals and Benthic Foraminifera on Surface Sediments in Masan Bay and Gadeog Channel, Korea)

  • 우한준;조진형;최재웅
    • Ocean and Polar Research
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    • 제29권3호
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    • pp.233-244
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    • 2007
  • Nine surface sediments from Masan Bay and Gadeog Channel were taken for grain size and geochemical and foraminiferal analyses in August 2002. The sediments consist of mud with 7.29-8.54 $\phi$ in mean grain size. Average concentrations of Al, Fe and Mn are higher in Gadeog Channel than those in Masan Bay. On the other hand, average concentrations of Pb, Cu, Zn, Cd, Cr, Ni and V are higher in Masan Bay than those in the channel. The latter group of elements show the highest concentration at station M4, off the outfall of treated wastewater disposal. Eighty-one foraminiferal species are identified in total assemblages, including 21 species of living populations. The number of individuals, species number, species diversity and equitability in Masan Bay have lower values than those in Gadeog Channel. The foraminiferal fauna off the outfall is relatively poor. Compared to geochemical and foraminiferal data obtained in 1996, heavy metals are more enriched, and the characteristics of foraminifera are little changed. These features indicate that the pollution of Masan Bay has not been reduced.

Growth of Loan Distribution and Bank Valuation: Evidence from Vietnam

  • HOANG, Lam Xuan;HOANG, Phi Dinh;DANG, Duong Quy
    • 유통과학연구
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    • 제18권5호
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    • pp.5-13
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    • 2020
  • Purpose: The aim of this article is to test the link between growth of loan distribution and Bank Valuation in Vietnam's banking sector. At the same time, the study also compared the differences in the effect of growth of loan to valuation bank in banks of different sizes, ownership rates and bank values. Research design, data and methodology: With panel data estimation techniques along with robust standard error for a sample of the banks listed on Vietnam stock exchange from 2012 to 2019. Results: Growth of loan has a positive impact on Bank Valuation (by Tobin's Q). A closer investigation provides evidence for the differential valuation effect of loan growth depending on different features of banks. Specifically, loan growth is found positively and significantly associated with Bank Valuation in small and non-state-owned banks only. Besides, bank size, deposit, and return on equity are found negatively associated with Tobin's Q, while loan loss provisions exhibit a positive relation with this measure of Bank Valuation. Conclusions: These findings provide contributions to the literature on the existence of the effect of loan growth on Bank Valuation. At the same time, the study also provides practical implications for policy makers in banks and investors.

Czochralski 방법에 의한 Nd : YAG 단결정의 육성 및 레이저 출력특성 (Growth of Nd:YAG single crystal by czochralski method and characteristics of laser generation)

  • 이상호;김한태;배소익;정수진
    • 한국광학회지
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    • 제9권3호
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    • pp.175-180
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    • 1998
  • 고체 레이저매질로 가장 널리 쓰이는 Nd:YAG 단결정을 Czochralski 방법으로 육성하였다. 자체 제작한 Czochralski 결정 육성로 및 자동 결정 적경제어 장치를 써서 유효 직경 50mm, 길이 100mm의 Nd3+ 이온농도가 0.9at%이고 <111>방향의 단결정을 육성하였다. 단결정 육성시 융액의 수직방향에 대한 온도구배가 중용한 변수인 것이 확인되었으며, 결정 직경은 자동 제어가 가능하도록 컴퓨터 프로그램을 제작하였다. 육성된 단결정을 절단, 가공, 연마, 코팅 과정을 거쳐서 레이저 발진용 Nd:YAG막대를 제작하고 흡수 스펙트럼, 형과 스펙트럼 분석을 통하여 정확한 Nd:YAG의 레이저 발진특성을 확인하였다. 자체 가공된 레이저 막대로부터 발진된 CW 레이저의 최대 출력은 70W이었고, 발진문턱값과 효율은 각각 1.3kW, 1.64%이었다.

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A Rapid and Efficient Method for Construction of an Infectious Clone of Tomato yellow leaf curl virus

  • Bang, Bongjun;Lee, Jongyun;Kim, Sunyoung;Park, Jungwook;Nguyen, Thao Thi;Seo, Young-Su
    • The Plant Pathology Journal
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    • 제30권3호
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    • pp.310-315
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    • 2014
  • Tomato yellow leaf curl virus (TYLCV), a member of the genus Begomovirus, is responsible for one of the most devastating viral diseases in tomato-growing countries and is becoming a serious problem in many subtropical and tropical countries. The climate in Korea is getting warmer and developing subtropical features in response to global warming. These changes are being accompanied by TYLCV, which is now becoming a large problem in the Korean tomato industry. The most effective way to reduce damage caused by TYLCV is to breed resistant varieties of tomatoes. To accomplish this, it is necessary to establish a simple inoculation technique for the efficient evaluation of resistance to TYLCV. Here, we present the rolling circle amplification (RCA) method, which employs a bacteriophage using phi-29 DNA polymerase for construction of infectious TYLCV clones. The RCA method is simple, does not require sequence information for cloning, and is less expensive and time consuming than conventional PCR based-methods. Furthermore, RCA-based construction of an infectious clone can be very useful to other emerging and unknown geminiviruses in Korea.

계성의『원치』에 관한 기초적 연구 (A Basic Study on the Yuarye of Ji Cheng)

  • 이유직;황기원
    • 한국조경학회지
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    • 제23권2호
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    • pp.223-241
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    • 1995
  • Ji Cheng's great work on garden design, the 'Yuanye'(Craft of garden), written in 1631 and originally published in 1634 is the first surviving manual on landscape gardening in the Chinese tradition. This study aims at investigating not only Ji Cheng's life, achievements companionship and design activities, but also the xylographic copies, literary style, and framework of Yuanye in their historical context in order to provide the bases for further study, Ji Cheng was exellent in poetry and painting. And he constructed Dongdiyuan in Changzhou around 1623, Wuyuan in Yiaheng in 1631, and Yingyuan in Yangzhou around 1634 But no poems, paintings, and gardens designed by hi shill exist Therefore his design phi philosophy is able to be interpreted only by his work, Yuanye. After publishing, Yuanye fell into obscurity for several centuries in Chlna. It was redescovered and reprinted for the first time in 1931. Yuanye is composed of prefaces and main text The main text is divided into 'the Theory of Construction' and 'on Gardens', and the latter also into 10 sections. In this text Ji Cheng explains the aesthetic principles underlying garden design and the appropriate emotional response to various efftcts Especially, he emphasizes the importance of basin the garden design on the taxi ting nature and features of landscape and making use of natural scenery. The literary style of the book is highly mannered, and there are so many poetic descriptions and Ji Cheng's native Jiangsu dialects. So the translation of the original text is very difficult After this, the major design concepts of Ji Cheng's landscape gardening theory and whole network of these concepts have to be studied.

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Clinical Pearls and Advances in Molecular Researches of Epilepsy-Associated Tumors

  • Phi, Ji Hoon;Kim, Seung-Ki
    • Journal of Korean Neurosurgical Society
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    • 제62권3호
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    • pp.313-320
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    • 2019
  • Brain tumors are the second most common type of structural brain lesion that causes chronic epilepsy. Patients with low-grade brain tumors often experience chronic drug-resistant epilepsy starting in childhood, which led to the concept of long-term epilepsy-associated tumors (LEATs). Dysembryoplastic neuroepithelial tumor and ganglioglioma are representative LEATs and are characterized by young age of onset, frequent temporal lobe location, benign tumor biology, and chronic epilepsy. Although highly relevant in clinical epileptology, the concept of LEATs has been criticized in the neuro-oncology field. Recent genomic and molecular studies have challenged traditional views on LEATs and low-grade gliomas. Molecular studies have revealed that low-grade gliomas can largely be divided into three groups : LEATs, pediatric-type diffuse low-grade glioma (DLGG; astrocytoma and oligodendroglioma), and adult-type DLGG. There is substantial overlap between conventional LEATs and pediatric-type DLGG in regard to clinical features, histology, and molecular characteristics. LEATs and pediatric-type DLGG are characterized by mutations in BRAF, FGFR1, and MYB/MYBL1, which converge on the RAS-RAF-MAPK pathway. Gene (mutation)-centered classification of epilepsy-associated tumors could provide new insight into these heterogeneous and diverse neoplasms and may lead to novel molecular targeted therapies for epilepsy in the near future.

한반도 중서부 근 ${\cdot}$ 외해의 표층 퇴적물 특성과 퇴적환경 (Depositional Environments and Characteristics of Surface Sediments in the Nearshore and Offshore off the Mid-Western Coast of the Korean Peninsula)

  • 오재경;금병철
    • 한국지구과학회지
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    • 제22권5호
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    • pp.377-387
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    • 2001
  • 한반도 서해 중부지역의 대륙붕과 연안의 경계인 근${\cdot}$외해의 퇴적환경과 퇴적작용을 연구하기 위하여 1996년 부터 1999년 사이에 연속적으로 84개의 표층퇴적물을 채취하여 분석하였다. 연구지역 표층퇴적물은 역질 사(gravelly Sand), 사(Sand), 실트질 사(silty Sand) 그리고 사질 실트(sandy Silt)의 퇴적상을 보이고 있다. 조직변수는 표준입도 -0.39${\sim}7.82{\Phi}$, 분급도 0.36${\sim}4.68{\Phi}$, 왜도 -0.38${\sim}$0.86, 첨도 -1.56${\sim}$3.43로서 다양한 분포를 보이며 중앙지역의 조립하고 분급도가 좋은 사질 퇴적물을 중심으로 연안, 북과 남쪽으로 갈수록 세립해지고 분급도가 나빠지는 경향을 나타내며, 조석우세환경을 나타내는 양의 왜도를 나타내고 있다. 퇴적기작은 3가지(밑짐이동, 점이부유, 지속적 부유) 양상에 의하여 3지역으로 구분된다. 파랑, 조류의 영향으로 밑짐이동(mode A)으로 운반, 재분포된 북부지역, 상대적으로 지속적 부유(mode C)에 의한 이동, 운반, 퇴적된 남부지역 그리고 3가지 양상이 복합(mode B)되어 나타나는 중앙지역으로 구분된다. 따라서, 연구지역인 근${\cdot}$외해지역 퇴적환경은 강의 공급, 잔류퇴적물 그리고 수리학적 작용에 의해서 중앙, 남, 북부 지역으로 구별된다. 결론적으로 서해 중부 근${\cdot}$외해지역은 복잡한 수리학적 작용에 의한 다양한 퇴적기작으로 재배치된 연안의 육성기원퇴적물과 대륙붕의 잔류퇴적물이 특징적이며, 이런 퇴적작용으로 인해 연안에서 대륙붕으로 연결시켜주는 전이지역으로서의 퇴적환경을 보여주고 있다.

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