• 대한치과의사협회지
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• 제12권2호
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• pp.113-118
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• 1974

The importance of light and stress as factors in growth has not previously been clearly delineated. As the result of using experimental environments on growth rate of incisors in 24 young rats with body weight ranging 58 Gm to 62 Gm., the author obtained following conclusions. 1) The eruption rate of normal rats incisors was 0.421mm in upper incisors and 0.592mm in lower incisors per a day respectively. 2) In light environment, growth rate of incisors in rats and body weights were found to increase more rapidly during the 8-week experimental period in comparison with any environments. 3) In stress environment, growth rate of incisors in rats and body weight were found to decrease in comparison with amy environments during the 8-week experimental period.

• 한국안전학회지
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• 제14권2호
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• pp.3-10
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• 1999

Fatigue crack growth rates in commercial plate of high strength Al 7075-T651 were investigated for the T-L direction in air, water and sea water. In this paper the effect of cyclic load wave-form(trapezoid and triangle) on fatigue crack growth rates in air, water and sea water environments were investigated using standard LEFM testing procedures. It was founded that the fatigue crack growth behaviors were not affected by cyclic load wave-forms. In region II (stable crack growth region), the fatigue crack growth behaviors were insensitive to cyclic load wave-forms and were sensitive to environment i.e. fatigue crack growth behaviors were higher in sea water than in air for all cyclic load wave-form. The result of fractographical morphology in air, water and sea water by SEM showed obvious dimple rupture and typical striation in air, but transgranular fracture surface in water and sea water. The values m are not affected by corrosion environments but C are different values.

• 한국농림기상학회지
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• 제4권2호
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• pp.65-71
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• 2002

임간인삼의 생육특성을 조사하기 위해서 활엽수, 침엽수, 혼효림 3가지 연구지를 선정하였다. 연구지는 이미 산지인삼이 비슷한 연령으로 분포하는 지역을 선정하였고 대상 연구지의 환경과 생육특성 등을 조사하였다. 세 임분 공동적으로 상층목의 평균 수령이 20~25년이고 평균 DBH는 14~17cm였다. 평균 수고는 약 7.8~8.5 m 정도였다. 하층식생으로는 마, 더덕, 실새풀 등의 초본류가 차지하고 있다. 산지인삼의 생육은 활엽수림에서 생장한 산지인삼이 침엽수나 혼효림의 것보다 약간 좋은 것으로 나타났지만 그 차이가 미세해서 내년도에 연령이 많은 산지인삼을 대상으로 더 자료를 수집할 필요가 있다. 앞으로 이러한 기초자료를 토대로 생리적인 자료를 확보하는 것이 필요하고, 그러기 위해서 광합성능력, 기공의 형태, 증산량 등의 생리적인 자료를 확보해야 한다.

• 기술혁신연구
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• 제8권1호
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• pp.125-153
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• 2000

This study empirically examined the relationships between the growth stage of ventures and their business characteristics such as KSFs, environmental attributes, CEO roles, and utilization of external resources, based on data from 2,515 Korean ventures. ANOVA results of this study revealed that 1) Key success factors appeared different across the different growth stage of Korean ventures. Financial resources were most critical in the early stage of growth, while the foreign technology licensing appeared to be most important for the success of ventures at later growth stage; 2) As the Korean ventures grew, their environments became more dynamic and hostile; 3) Strategic and external activity roles of top management were critical in younger ventures, while roles for marketing and production were important in older ventures; and 4) Utilization of external resources were more frequent at the later stage of ventures than at the early stage of growth. Based on the research, this study offered several managerial, theoretical, and policy implications.

• 전자통신동향분석
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• 제33권6호
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• pp.12-23
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• 2018

In this paper, we review the technical trends of diamond and gallium oxide ($Ga_2O_3$) semiconductor technologies among ultra-wide bandgap semiconductor technologies for harsh environments. Diamond exhibits some of the most extreme physical properties such as a wide bandgap, high breakdown field, high electron mobility, and high thermal conductivity, yet its practical use in harsh environments has been limited owing to its scarcity, expense, and small-sized substrate. In addition, the difficulty of n-type doping through ion implantation into diamond is an obstacle to the normally-off operation of transistors. $Ga_2O_3$ also has material properties such as a wide bandgap, high breakdown field, and high working temperature superior to that of silicon, gallium arsenide, gallium nitride, silicon carbide, and so on. In addition, $Ga_2O_3$ bulk crystal growth has developed dramatically. Although the bulk growth is still relatively immature, a 2-inch substrate can already be purchased, whereas 4- and 6-inch substrates are currently under development. Owing to the rapid development of $Ga_2O_3$ bulk and epitaxy growth, device results have quickly followed. We look briefly into diamond and $Ga_2O_3$ semiconductor devices and epitaxy results that can be applied to harsh environments.

• 환경영향평가
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• 제20권4호
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• pp.455-464
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• 2011

The purpose of this study is to clarify correlations between soil environments and the growth of trees in forests and thereon analyze effects of seasonal changes in such environments on such growth. To determine seasonal factors of soil affecting the Tree Vitality of Pinus thunbergii, first of all, the study designated the Tree Vitality as a dependent variable and soil hardness, moisture, pH, K, Na, Mg and Ca as independent variables. Then the study performed Pearson's coefficient analysis. To clarify what soil factors influence the seasonal growth of Pinus thunbergii multiple regression analysis is carried out, and findings are as follow; the growth of Pinus thunbergii was basically influenced by pH, followed by soil hardness in spring, K, followed by moisture in summer, and by soil hardness in winter. However, no soil factors affected the vitality at the significance level of 5% for t.

• Steel and Composite Structures
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• 제19권6호
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• pp.1549-1560
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• 2015

This paper presents the characterization of fatigue crack in the A283 Grade C steel using the MMM method by identifying the effects of magnetic flux leakage towards the crack growth rate, da/dN, and crack length. The previous and current research on the relation between MMM parameters and fatigue crack effect is still unclear and requires specific analysis to validate that. This method is considered to be a passive magnetic method among other Non-Destructive Testing (NDT) methods. The tension-tension fatigue test was conducted with a testing frequency of 10 Hz with 4 kN loaded, meanwhile the MMM response signals were captured using a MMM instrument. A correlation between the crack growth rate and magnetic flux leakage produces a sigmoid shape curve with a constant values which present the gradient, m value is in the ranges of 1.4357 to 4.0506, and the y-intercept, log C in the ranges of $4{\times}10^{-7}$ to 0.0303. Moreover, a linear relation was obtained between the crack length and magnetic flux leakage which present the R-Squared values is at 0.830 to 0.978. Therefore, MMM method has their own capability to investigate and characterize the fatigue crack effects as a main source of fracture mechanism for ferrous-based materials.

• Asian-Australasian Journal of Animal Sciences
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• 제8권3호
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• pp.241-247
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• 1995

The aim of the present study was to investigate the effect of internal parasites on growth rates of Thai Native (TN) and crossbred (75% TN $\times$ 25% Anglo-Nubian, AN and 50% TN $\times$ 50% AN) goats (undrenched, drenched every 3 weeks or at 9 weeks) in village environments in southern Thailand in a humid tropical climate. There was no significant (p > 0.05) difference in growth rate ($g/kg^{0.75}/d$) between the genotypes during unsupplemented grazing (0-64 days of the experimental period). However, during supplementary feeding (64-127 days) and throughout the period (0-127 days) TN goats had significantly (p < 0.01) lower growth rates compared with 75% TN $\times$ 25% AN and 50% TN $\times$ 50% AN goats. There was no (p > 0.05) significant difference in growth rates between 75% TN $\times$ 25% AN and 50% TN $\times$ 50 % AN goats. The growth rates of goats drenched every 3 weeks were significantly (p < 0.01) higher than those undrenched or drenched at 9 weeks. The results of this study also indicate that drenching alone did not result in increased weight gain except when the nutritional status was also improved. Parasitic infection affected some blood constituents, such as pack cell volume, haemoglobin, total protein and albumin. This resulted in lower growth rates for control groups and goats drenched at 9 weeks compared to those of goats drenched every 3 weeks.

• 한국통신학회논문지
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• 제29권6A호
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• pp.589-599
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• 2004

소프트웨어의 신뢰성을 정량적으로 평가하는 데 있어서 대다수의 모델이 발생된 소프트웨어 고장의 발생원인에 대한 완전한 수정을 요구하는 완전 디버깅 환경을 가정하고 있다. 그러나 실제 개발자가 디버깅 작업을 수행할 때 완전한 수정이 불가능하기 때문에. 새로운 결함이 삽입되는 경우가 많다. 즉, 결함 수정은 불완전 환경에 처한다. 본 논문에서는 결함 수정시 신규 결함의 삽입 가능성을 고려하고 불완전 디버깅 환경에 대한 소프트웨어 신뢰도 성장모델을 제안하고 소프트웨어 동작 환경 하에서 발생된 소프트웨어 고장과 시험 전 소프트웨어 내의 고유 결함에 의한 고장과 동작 중에 랜덤하게 삽입된 결함에 의해 발생되는 고장 등 2종류의 결함을 고려하여 비동차포아송과정(NHPP)에 의한 소프트웨어 고장발생 현상을 기술한다. 또 소프트웨어 신뢰성 평가에 유용한 정량적인 척도를 도출하고 실측 데이터를 이용하여 적용한 결과를 제시하고 기존 모델과의 적합성을 비교, 분석한다.

• 한국환경과학회지
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• 제19권11호
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• pp.1323-1336
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• 2010

This study was carried out to determine marine environments and phytoplankton community around Mokpo harbour on March to November during the period of 2004-2009. The remarkable fluctuations of marine environments were shown around Mokpo harbour depending on monthly and yearly. Among seasons, summer was a great that was associated with extremely releasing the freshwater from Youngsan River Weir, contributing to effect the fluctuations of water quality. Nevertheless of monthly and yearly, the molecular ratio of N:P was always shown in above 16 that was mainly attributed to freshwater discharge on March to November. This indicates that phosphorus playes an important role in limiting factor as growth in phytoplankton. During this study, Skeletonema costatum was found to be richer than the other groups of diatoms in terms of abundance and species number. Mokpo harbour, with the presence of a narrow avenue for exchange with offshore waters, has limited growth in phytoplankton, but this species is able to well adapt and fast grow under even high level of suspended solid and low intensity of light compared with other species. The discharge of freshwater is associated with significantly fluctuation of marine environments in this region, but it does not affect the quantitative and qualitative distribution of phytoplankton. It is necessary to persistently monitor based on water quality and phytoplankton community.