• 한국환경복원기술학회지
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• 제16권2호
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• pp.53-61
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• 2013

The present study elucidated the growth properties of Sasa borealis communities distributed in the lower layer of deciduous broadleaf forests in temperate zones and analyzed the correlation between the growth properties of S. borealis and positional environmental factors. The higher the culm height of S. borealis was, the higher the values of the leaf number, leaf area, and foliage layer thickness became. This might be because as the culm height of S. borealis increased, the acquisition of light sources became easier so that the biomass of leaves increased simultaneously for smooth anabolism. S. borealis seem to change their growth mode for smooth acquisition of light resources. The culm density of S. borealis and the leaf number, leaf area and foliage layer thickness of S. borealis did not show any clear correlation. The values of the culm height, leaf number, leaf area, and foliage layer thickness of S. borealis as the above altitude of the location of S. borealis increased. It seems like that growth conditions such as temperatures and winds are deteriorated as the above altitude of the location of S. borealis increased so that S. borealis becomes smaller. No clear correlations were shown between the physiochemical properties of soil and S. borealis' growth properties. It seems like that the growth of S. borealis complexly intertwined with diverse environmental factors and that due to the physiological integration of S. borealis, certain physiochemical properties do not unilaterally affect S. borealis' growth properties.

• 한국환경복원기술학회지
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• 제13권2호
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• pp.52-62
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• 2010

This study was carried out in the Tropical Plant Resources Research Center of Korea National Arboretum to determine the optimum edaphic environment for the growth of tropical and subtropical plants. The physicochemical properties of artificial substrates and the growth characteristics of tropical and subtropical plants were investigated. Subtropical plants exhibited a high growth rate when cultivated in a substrate of Dry Zone that had physical properties similar to those of arid native soil. Mediterranean plants showed a low growth rate when grown in a substrate of Subtropical Zone that required changes in acidity. The substrate of Tropical Zone had high organic matter and mineral contents and therefore had good physical properties:this substrate has a good environment for the stimulation of the growth of tropical plants. Our results indicate that the chemical properties such as pH and mineral contents of most artificial substrates need to be more urgently improved than their physical properties in order to ensure better growth of tropical and subtropical plants. Initial management strategies for the construction of new tropical greenhouses were formulated, and data from monitoring studies will be continuously gathered and incorporated in the manual to keep it updated.

• 한국유기농업학회지
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• 제9권1호
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• pp.61-73
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• 2001

This study was conducted to investigate the effect of sewage sludge application on the growth of chinese cabbage and the changes of chemical properties of soil. The experiment were set up with two different place and cultivated from Feb. 10 to June. 20 of 2000. Treatments are 0, 1.25, 2.5, 5, 10 and 20kg/3.3$\m^2$ of sewage sludge applicated into the soil and recorded the growth characteristics. Chemical properties of soil were also analysed before and after treatment. The application of the sewage sludge resulted in increasing the content of EC, cations exchange capacity, available phosphate and organic matter. And increased the growth characteristics in terms of the number of leaves, leaf area, fresh and dry weight regardless of crops experiments. Optimum amount of the sewage sludge depended on chemical properties of soil used. This results demonstrated that application of sewage sludge in the soil attribute to have play an important both improving soil chemical properties and promoting the crop growth. As lowering the soil pH(pH 6) heavy metal content increased compared with higher pH(pH 7). Feasibility was recognized in the application of sewage sludge as a fertilizer for the growth of chinese cabbage. Detrimental effects such as heavy metal in the soil and crop followed by the application of sewage sludge was not observed.

• 한국초전도ㆍ저온공학회논문지
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• 제19권3호
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• pp.33-39
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• 2017

This study presents that the orientation and the geometry of seed affect on the growth behavior of melt processed single grain REBCO bulk superconductor and its magnetic properties. The effects of seed geometry have been investigated for thin $30mm{\times}30mm$ rectangular powder compacts. Single grain REBCO bulk superconductors have been grown successfully by a top seed melt growth method for 8-mm thick vertical thin REBCO slab. Asymmetric structures have been developed at the front surface and at the rear surface of the specimen. Higher magnetic properties have been obtained for the specimen that c-axis is normal to the specimen surface. The relationships between microstructure, grain growth and magnetic properties have been discussed.

• 기술혁신연구
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• 제5권1호
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• pp.15-43
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• 1997

This paper investigates empirically the relationship between various business portfolio properties (particularly technological properties) and chaebol's performance using data on the 50largest chaebols in Korea. In addition to the traditional indexes to measure diversification such as entropy index, we calculated inter-industry technological similarity using R'||'&'||'D expenditure data by industry and 1990 Input-output Table in korea, and obtained chaebol-level technological relatedness and internal transaction proportion from chaebols' business profile, inter-inustry technological similarity and 1990 input-output table. We applied factor analysis on 13 business portfolio property indexes and showed that they could be grouped into 3 dimensions. diversification scope, inter-business relatedness and degree of vertical integration. In this paper, using 50 largest chaebols' financial data (1989-1994), we analyzed empirically the effect of business portfolio properties on ROS(Return On Sales) which is conventional index for firm performance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness in not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business portfolio properties, we obtained three findings. First, only VI(Vertical integration) has a significant positive correlation with ROS. Second, when using TFP growth as an dependent variable, both TR(Technological Relatedness) and VI are significant and positively related to the dependent variable. Third, the interaction term between TR and VI is significant and negatively affects TFP growth, meaning that TR and VI are substitutes. These results suggest strategic directions on restructuring business portfolio. As VI is increased, chaebols will get more profit. A higher level of either TR or VI will increase TFP growth rate, but increase in both TR and VI will have a negative effect on TFP growth. To summarize, certain business portfolio properties such as VI and TR can be considered "resources" themselves since they can affect profit rate and productivity growth. VI and TR have a synergy effect of change in profit rate and productivity growth. VI increases ROS and productivity growth, while TR increases productivity growth representing a technological synergy effect.t.

• 한국주조공학회지
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• 제5권4호
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• pp.258-270
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• 1985

The structures and mechanical properties of undirectionally solidified Sn-Zn eutectic alloys have been examined over the growth range 7mm/h to 6,000mm/h. The structures of unidirectionally solidified Sn-Zn eutectic alloys were primarily broken-lamellar at growth rates below 760mm/h and became fibrous at higher growth rates above that. At a growth rate 3,084mm/h the structures were fibrouse only. There is no dendrites at any growth rates, but occasionally ribbon-like morphologies were seen. The under cooling increased parabolically with growth rate increase. The hardness of specimes increased with growth rates increase but heat-treated specimen decreased after growth rates 760mm/h and became constant value. The effect of heat-treatment was good at lower growth rate. At room temperature tensile strength increased with growth rates up to R=990mm/h and then tensile strength became near-constant value. The effect of heat-treatment was well at lower growth rate.

• 한국지능시스템학회논문지
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• 제13권5호
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• pp.621-626
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• 2003

In this paper, we modeled a virtual life (VL) that reacts to the user s action according to its own behavioral characteristics and grows itself. We established some conditions with which such a VL is designed. Genetic Algorithm is used for the growth process that changes the VL s properties. In this process, the parameter values of the VL s properties are encoded as one chromosome, and the GA operations change this chromosome. The VL s reaction to the user s action is determined by these properties as well as the general expectation of each reaction. These properties are evaluated through 5 fitness measures so as to deal with multi-objective criteria. Here, we present the simulation of the growth Process, and show some experimental results.

• 반도체디스플레이기술학회지
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• 제11권1호
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• pp.61-65
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• 2012

In this study, for use of carbon nanotubes (CNTs) as a cold cathode of x-ray tubes, we examine the effects of selective growth of CNTs on their field emission properties and long-term stability. The selective growth of CNTs was performed by selectively etching the catalyst layer which was used for CNTs' nucleation. CNTs were grown on conical-type tungsten substrates using an inductively-coupled plasma chemical vapor deposition system. For all the grown CNTs, their morphologies and microstructures were analyzed by field-emission scanning electron microscope and Raman spectroscopy. The electron-emission properties of CNTs and the long-term stability of emission currents were measured and characterized according to the CNTs' growth position on the substrate.

• 한국결정성장학회지
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• 제11권5호
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• pp.211-217
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• 2001

Czochralski법에 의한 ZnWO₄단결정을 [100], [101], [001] 방향으로 성공적으로 성장시켰다. 각 축 방향에 따른 성장조건이 rotation speed, pulling rate, 성장된 결정의 직경 등의 변수를 가지고 조사되어졌다. 성장된 결정의 냉각시 발생되는 균열을 annealing 효과에 의하여 방지할 수 있었다. 성장된 결정의 방위는 Laue back reflection으로 결정하였다. 각 축 방향으로 성장된 결정의 미세구조적 특징이 논하여졌으며, 경도, 열팽창계수 및 유전상수의 물리적 특성이 평가되어졌다.

• 보존과학연구
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• 통권17호
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• pp.48-64
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• 1996

We compared the degree of color difference formed by environmental factor(temperature, relative humidity) with fungal growth in order to know how to change the color difference of cellulolutic cultural properties such as Korean papers, cotton, jute and hemp. We concluded, from the result, that the action of fungal growth on celluloytic cultural properties was more hamful than environmental factor. We considered the secretion produced by fungi as the causative agent for stained formation on cellulolytic cultural properties. Alternaria sp. colored allmaterials greyish black, Chaetomium sp. colored cotton and hemp orange, and Penicllium sp. colored cotton, jute and hemp yellowish green. But Trichoderma sp. and Aspergillus sp. didn't show a clear color against each material. It was observed that thymol(120g/$m^3$) was the most effective fungicide to prevent fungal growth.