• 한국연초학회지
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• 제19권1호
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• pp.18-23
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• 1997

The study was carried out to clarify reasonable production of healthy seedling, optimal Pot depth, and appropriate transplanting time, which can be deduced from understanding of seedling quality. Seedling quality results from growth of root and shoot, morphology and distribution of root system under influence of Pot depth during seedling growing period. Stem height, shoot dry weight, leaf area and leaf number were increased in proportion to depth of pots. Growth of shoot and root during seedling growing period showed the most dramatic development between 20th and 25th day after temporary planting. Root number increased as pot depth decrease and total root length and dry weight increased as pot depth increase. In 5cm pot, relative multiplication rate was higher and mean extension rate was lower than other depth of Pot. The limitation of pot volume in which rhizosphere was located enhance the development of roots of second and third order. At 20th days after temporary Planting root distribution was relatively uniform in length and development of adventitious root on stem base was poor as Pot depth decreased.

• International Journal of Automotive Technology
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• 제6권3호
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• pp.229-234
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• 2005

The dynamic crack growth in ductile steel is investigated by means of the impact loaded 3 point bending (3PB) specimens. Results from experiments and numerical simulations are compared to each other. A modified 3PB specimen designed with the reduced width at its ends has been developed in order to avoid the initial compressive loading of the crack tip and also to avoid the uncertain boundary conditions at the impact heads. Numerical simulations of the experiments are made by using a finite element method (FEM) code, ABAQUS. The high speed photography is used to obtain the crack growth and the data of the crack tip opening displacement (CTOD). The direct measurements of the relative rotations of two specimen halves are made by using the Moire interference pattern.

• 한국분말재료학회지
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• 제6권1호
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• pp.81-87
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• 1999

Based on the pore filling theory, the microstructure evolution during liquid-phase sintering has been analyzed in terms of interrelationship between average grain size and relative density. For constant liquid volume fraction, the microsturucture trajectories reduced to a single curve in a grain size(x)-density(y) map, regardless of grain growth constant. The slope of curves in the map was inversely proportional to average pore size, while it increased fapidly with liquid volume fraction. Increase in pore volume fraction retarded the densification considerably, but showed marginal effect on the slope. The activation energy of densification was predicted to be the same as that of grain growth as long as the liquid volume fraction is constant for any temperature range studied. The present analyses on microstricture evolution may demonstrate the usefulness of pore filling theory and provide a guideline for process optimization of liquid-phase sintering.

• Journal of Ginseng Research
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• 제12권1호
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• pp.87-91
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• 1988

일복개량의 일환으로 일복의 피복재선택을 위한 기초자료를 얻고자 적색광, 청색광 및 백색광하에서 미국인삼(Panax quinquefolin L.)의 광합성을 측정하였다. 광질별 광합성량은 전반적으로 적색과, 백색광 및 청색광 순으로 많았으며 그 광합성량의 차이는 조도가 증가할수록 감소되었다. 따라서 일복의 피복물 색상은 적색으로 하는 것이 인삼(미국인삼) 생육에 유이할 것임을 시사되었다.

• 한국정보처리학회논문지
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• 제7권3호
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• pp.852-861
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• 2000

Software reliability growth models are used in testing stages of software development to model the error content and time intervals betwewn software failures. In this paper, using priors for the number of fault with the negative binomial distribution nd the error rate with gamma distribution, Bayesian inference and model selection method for Jelinski-Moranda and Goel-Okumoto and Schick-Wolverton models in software reliability. For model selection, we explored the sum of the relative error, Braun statistic and median variation. In Bayesian computation process, we could avoid the multiple integration by the use of Gibbs sampling, which is a kind of Markov Chain Monte Carolo method to compute the posterior distribution. Using simulated data, Bayesian inference and model selection is studied.

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2003년도 학술대회
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• pp.121-124
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• 2003

The goals of this study is to elucidate life cycle and to detect genetic differences within a single species of Heterosigma akashiwo. To elucidate life cycle of H. akashiwo, have to study of benthic stage and vegetative cell. So we studied identification of H. akashiwo cyst. The relative contents of DNA in nuclei were determined in Heterosigma akashiwo. Different stages of the life history were obtained from culture and natural sediments, and examined by microfluorometry after staining with the DNA-specific fluorochrome 4'-6-dianudubi-2-phenylindole(DAPI). Large cells mainly in exponensial stage, while small cell, pre-encystment cells(\ulcorner\ulcorner), showed in the end of the late growth stage. Type of DNA content showed the different with growth stage. Usually the small cell has the high level of IOD.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.75.1-75.1
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• 2013

Atomic layer deposition (ALD) and molecular layer deposition (MLD) are based on sequential, self-limiting surface reactions that produce atomic layer controlled and conformal thin film growth. ALD can deposit inorganic films and MLD can deposit films containing organics. ALD and MLD can be used together to fabricate a wide range of hybrid organic-inorganic alloy films. The relative fraction of inorganic and organic constituents can be defined by controlling the ratio of the ALD and MLD reaction cycles used to grow the film. These hybrid films can be tuned to obtain desirable mechanical, electrical and optical properties. This talk will focus on the growth and properties of metal alkoxide films grown using metal precursors and various organic alcohols that are known as "metalcones". The talk will highlight the tunable mechanical properties of alucone alloys grown using Al2O3 ALD and alucone MLD and the tunable electrical conductivity of zincone alloys grown using ZnO ALD and zincone MLD with DEZ and hydroquinone as the reactants.

• KDI Journal of Economic Policy
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• 제41권3호
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• pp.77-96
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• 2019

This paper examines the relation between the skill premium and international trade given differences in the relative supply of skills across countries while allowing the South (developing countries) to develop its appropriate technology. Typical assumptions put forward in the literature state that either technology is exogenously given, or technical change is allowed only in the North (developed countries). I present a model of international trade with endogenous growth by allowing the South to direct its technology. The results show that more R&D is directed towards skill-augmenting technology in the North than in the South, in sectors with the same skill-intensity. Technical change induced by lowering trade costs can increase the skill premium in both the North and the South. This result can explain the empirical observation that the skill premium has increased within many developing countries after they experienced trade liberalization. Finally, the model predicts larger gains from trade compared with the model where technical change is either not allowed, or allowed only in the North.

• 한국자원식물학회지
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• 제11권3호
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• pp.326-334
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• 1998

Vascular cambium in 16 species of Salicaceae is nonstoried in all of them and is made up of fusiform and ray initials. The growth of cambial girth occurred by pseudotransverse division of fusiform initials and subsequent apical intrusive growth of daughter initials. The measurements of fusiform initials in tangerntial sections have revealed that the average length varies from 252.2-437.1${\mu}{\textrm}{m}$ in investigated species, with the maximum being in Populus euramericana and the minimum in Salix purprea var. Multinervis. The length of fusiform initials depends on the length of the tapering end wall , therefore, the longer the length of the tapering end wall, therefore, the longer the length of the taperding end wall, the longer the length of fusiform initials. Ray initials have their own size, magnitude, and frequency of occrrence in each species. The relative proportion of ray initials fall about 15.0-24.5% in Salicaceae. Shrubby species of Salix have a lower ratio of ray initials than the species which possess wider trunks. New ray initials are originated from cut off the side or the end of fusiform initials and central partition of a fusiform initials.

• 한국산림과학회지
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• 제85권3호
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• pp.539-551
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• 1996

본 연구에서는 위치종속조사가법에 의해 소나무임분에서 조사된 자료로부터 임목의 크기 및 경쟁목과의 거리를 함께 고려한 개체목차원의 거리종속경쟁지수와 전통적인 임분차원의 밀도척도를 추정하고 이들을 흉고직경생장과 비교하여 경쟁상태에 대한 설명력을 검토하였으며, 경쟁지수가 영향변수로 고려된 개체목 흉고직경생장식을 유도하였다. 경쟁목선정방법에 있어 경쟁치단각도를 30도로 설정했을 때의 경쟁지수가 흉고직경생장과 기장 높은 상관관계를 보인 반면, 경쟁구역거리는 흉고직경생장추정에 대한 경쟁지수의 설명력에 미미한 영향을 미치는 것으로 나타났다. 개체목별 거리종속경쟁지수에 근거한 대부분의 임분경쟁지수들은 임분의 경쟁상태를 비슷하게 나타내는 것으로 평가되었다. 임령과 지위지수의 영향을 배제한 상태에서의 편상관분석결과 Alemdag의 평균경쟁지수 및 상대공간지수가 흉고직경과 가장 높은 연관성을 나타냈는데, 이중 개체목의 위치를 파악하지 않고도 비교적 손쉽게 파악될 수 있는 상대공간지수가 임분의 평균흉고직경을 추정하는데는 좀더 적합한 것으로 판단되었다. 개체목차원의 거리종속 경쟁지수중에서, 지위 및 흉고직경의 영향을 배제시킨다면 Hegyi의 경쟁지수가 흉고직경생장과 가장 밀접한 영향관계에 있는 것으로 밝혀졌다. 이로부터 Hegyi경쟁지수 및 임령, 우세목수고, 개체목의 흉고직경을 영향인자로 하는 다음과 같은 흉고직경생장식을 유도하였다. $$dbh^{\prime}=3.975362676{\cdot}age^{-1.099274613}{\cdot}ho^{0.199893990}{\cdot}dbh^{0.269430865}{\cdot}HgCI^{-0.353643587}$$ 위의 식은 다른 조건이 같다면 지위지수는 흉고직경생장에 유리한 영향을 미치는 반면 임령 및 경쟁지수의 증가에 의해서는 흉고직경생장이 둔화된다는 일반생장법칙에 부합되어 흉고직경생장식으로 적합하다고 판단되며, 단목생장모델을 위한 함수식으로 활용될 수 있다.