• Journal of Environmental Science International
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• v.9 no.6
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• pp.483-488
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• 2000

In this study, the distribution characteristics of volatile organic compounds (VOCs) were investigated on the seasonal basis across spring, summer, and fall during the year of 1998. According to this analysis, most VOC species investigated exhibited strong temporal trends. Over diurnal scale, there distribution characteristics were affected by seasonal factors strongly. While they showed high day/night ratio pattern during spring, the pattern was reversed during fall. When the seasonal mean values were compared between the two seasons, the spring values were systematically higher than their counterparts in most cases. In addition when our VOC measurement date were compared with those reported from elsewhere, we were able to conclude that the VOC levels in the study area are comparable to the level weakly impacted by the regional emissions of VOCs. Although our data are not sufficient enough to systematically explain the atmospheric distribution and behavior of VOCs, the findings of strong correlations among some of VOC species suggests strong need for investigating their interactions in the earth\`s atmosphere.

• Journal of architectural history
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• v.5 no.1 s.9
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• pp.39-49
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• 1996

Accoring to many studies which concerned with the types of folk houses, there are many types of folk houses in Korean peninsula and its areal distribution had been determined by the barrier of mountains, in general. But we have neglected to examine the overlapped areal distribution still now. If two types of culture with different housing type contact at one region, it may interrelated each other and invent certain exclusive charicteristics. And there are its own attitude of traditional culture in Kyung-buk provingce where serveral types of folk houses settled together. The purpose of this research is to clarify the general pattern of culture in terms of folk houses in northern Kyung-buk province and to suggest a clue to solve the cultural inter-relationship each other, By classification of the collected plans in this area, the authors try to find out the charicteristics of the serveral types and there areal distribution. Finally, we can find out that certain types of folk houses located in northern Kyung-buk province had formed their cultural regions and these homogeneous regions are overlapped, partly.

• Journal of Advanced Marine Engineering and Technology
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• v.17 no.3
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• pp.80-87
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• 1993

The various configuration of thin-shaped bevel gears are used usually for such as main reduction gear of the hovercraft. But the reasonable and concise guide to thedesign of the se bevel gears is not yet obtained, since the tooth of bevel gear has complex form. The purpose of these investigation is to be establish the design guide and to propose the desirable configuration form for thin-shaped straight bevel gear. In this report, the desirable configuration is examined experimentally by clearing up the effect of web and rim thickness, rim support condition upon the load distribution and root stress distribution along the tooth trace. The results are summarized as follows. (1) The crowning of tooth trace exerts a significant effect on the root stress distribution of thin-shaped bevel gear. (2) As the desirable configuration of the thin-shaped bevel gear, it is to be recommended that the rim is supported at the heel side of tooth trace. (3) But, as special type, it is desirable that the rim is supported at the toe side.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.1
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• pp.9-18
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• 2007

We use PKI technology for the digital content distribution in mobile environment. Encoding method is used TtipleDES and digital signature is used RSA. For the efficient methods and processes to the digital content distribution, we proposed the mechanism which consists of the sequential steps including the digital contents encoding step, rights management information signature step, and interconnection steps. As a result of this study, we propose the efficient and safe processes for the mobile content distribution environment.

• Journal of the Korean Statistical Society
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• v.35 no.4
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• pp.419-439
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• 2006

The article develops a new class of distributions by introducing a nonnegative perturbing function to $t_\nu$ distribution having location and scale parameters. The class is obtained by using transformations and conditioning. The class strictly includes $t_\nu$ and $skew-t_\nu$ distributions. It provides yet other models useful for selection modeling and robustness analysis. Analytic forms of the densities are obtained and distributional properties are studied. These developments are followed by an easy method for estimating the distribution by using Markov chain Monte Carlo. It is shown that the method is straightforward to specify distribution ally and to implement computationally, with output readily adopted for constructing required criterion. The method is illustrated by using a simulation study.

• Journal of the Korean Ceramic Society
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• v.32 no.2
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• pp.147-154
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• 1995

Abnormal grain growth behavior of BaTiO3 ceramics with controlling of particle size distribution of calcined powder was investigated. The particle size distribution was controlled by changing the calcining temperature or by using of classification and regrinding process. With broadening of the normallized size distribution in calcined powder, it showeda normal grain growth behavior in sintered body due to an increase of volume fraction of seed grain in the calcined powder. It was supposed that the seed grains could easily contact each other for the rapid grain growth during sintering process and resulted in fast switching-over from abnormal to normal grain growth stage.

• The Korean Journal of Ecology
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• v.22 no.2
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• pp.89-94
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• 1999

Thirty-day-old seedlings of tomato (Lycopersicon esculentum) were treated with different concentrations of HgCl$_2$(0. 10 and 50 $\mu$M) for up to 20 days. and the detailed distribution of Hg absorbed and its toxicity in different plant parts (roots, stems and leaves) were investigated. The accumulation of Hg in plants increased with external Hg concentrations. and Hg is strongly retained by roots. Further. Hg content in leaves was various. showing more accumulation in older leaves. Seedlings exposed to toxic levels of Hg showed not only the reduction of dry weight and length of both shoot and root. and chlorophyll levels in leaves but also the enhancement of malondialdehyde (a lipid peroxidation product) formation in all plant parts investigated. These results suggest that physiological impairment of a plant exposed to Hg may be achieved by internal distribution of Hg absorbed and Hg-induced oxidative stress in different plant parts.

• The Korean Journal of Ecology
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• v.20 no.1
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• pp.1-8
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• 1997

This study was conducted to investigate the distributions of the native and introduced dandelins in the western Kyonggido area and to determine the environmental factor influencing distribution of dandelions. One hundered and thirty seven study sites were randomly selected along roadsides in urban areas, arable lands, apartment areas and industry regions, and vegetation, dandelion's seed characters and soil acidity were sureyed. Throughout the areas the introduced dandelions were more widely distributed than the native ones. The native dandelions were scarcely distributed in the developed areas and roadsides. The introduced dandelions were dominantly distributed in the new environments where soils were alkalized by the trban development, road pavement, and construction of new buildings, while the native ones were mostly distributed in the rural area with weakly acid soil. The seed production of the introduced ones were two times more than that of the native ones. The seed of the introduced ones were lighter than that of the native ones. The introduced ones yield seeds more than four times a year. These results suggested the urbanization and the seed characters to bet the two dominant factors influencing the distribution of dandelions.

• Journal of Environmental Science International
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• v.6 no.6
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• pp.605-612
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• 1997

This study is to evaluate the overall NPP(Net Primary Productions distribution in the Korean Peninsula from the satellite data(NOAA/AVHRR). This has been done using the linear relationship between the natural vegetation condition and the NPP. The NPP of natural vegetation increases proportional to the annual net radiation(Rn), where radiative dorless Index(RDI) is a proportional constant connecting Rn to NPP. Normalized Difference Vegetation Index(NDVI) Is used for monitoring vegetation change, and INDVI (Integrated NDVI) for annual analysis. The INDVI has a close relation to .Rn and NPP. which can be used effectively for estimating NPP distribution of where the meteorological data Is unavailable such as North Korea. The NPP distribution of the Korean Peninsula was estimated based on the model.

• Journal of Environmental Health Sciences
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• v.17 no.2
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• pp.127-139
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• 1991

Four group(Control I II, Treatment I II ) of Rats, each consisting of 10 rats, were studied Methylmercury Chloride MMc was orally given to Sprague-Dawley male at does of 10mg/kg (5 mg/kg $\cdot$ day), 10mg/kg after two weeks. This study was designed to investigate the distribution, the difference and the ratio of organic mercury, total mercury, zinc and copper in tissue, in each others group. The result were as follows: 1. There was no significantly difference in the body weight between two groups( p > 0.05). 2. There was significantly difference in the distribution of zinc concentration in liver, kidndey, blood, spleen between control I and treatment I, and in blood, spleen between control II and treatment II (P < 0.05). 3. There was significantly difference in the distribution of copper concentration in kidney, blood between control I and treatment I, and in spleen brain between control II and treatment II. 4. The ratio of zinc concentration in treatment/control was high at spleen. 5. The ratio of methylmercury/totalmercury was high at spleen.