• Parasites, Hosts and Diseases
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• v.30 no.1
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• pp.15-20
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• 1992

The Taenia species in East Asia, hitherto identified as Taenia saginata, has been recognized as differing from the classical descriptions of life cycles and was recently named Taenia saginata taiwanensis (tentatively until 1992) . Major differences between T. saginata and the newly recognized Asian T. saginata are their intermediate hosts and the infected tissues. Asian T. saginata metacestodes are found in the livers of pigs rather than in the muscles of cattle. In this study, we observed the natural infection status of Asian T saginata metacestodes in the livers of 25,358 pigs at an abattoir in Cheongju City, Korea, from 1989 to 1990. Total 256 livers(1.01%) were infected with 1∼96 (mean 2.5 per capita) metacestodes. Most of the metacestodes, however, were either calcified (87.1%) or highly degenerated (12.9%). Living metacestodes were found in only 0.01% (3/25,358) of the examined livers. And these were distributed randomly in each lobe of the livers. The liver of pigs in Korea was con- firmed as an organ hosting the Asian T. saginata metacestode. But its epidemiological significance as a source of human infections should be properly evaluated because of the rarity of the living metacestodes.

• Journal of the Korean GEO-environmental Society
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• v.7 no.6
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• pp.35-44
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• 2006

Various geophysical methods and geological survey were applied for prospecting of geothermal resources and the attitude of volcanic body at northern part of Kumseongsan, Euiseong. They include magnetic, self-potential, radioactive and resistivity methods, temperature logging near the earth's surface and geological survey. The results of this study are summarized as follows. Various geophysical anomalies is related to the geologically Cretaceous conduit. Anomalies of resistivity and temperature logging seem to be related to the geological structure and terrestrial heat. Small radioactive and self-potential anomalies seem to be associated with chemical character of rocks. The sedimentary rocks dip steeply toward the volcanic rocks, aquifuge. Ideal geological structure for bearing ground water and geothermal resources was founded in the study area. The study area and the adjacent two hot springs area consist of Cretaceous sedimentary and volcanic rocks, and have similar geology.

• Journal of Forest and Environmental Science
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• v.13 no.1
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• pp.1-27
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• 1997

This study was to survey the flora of resources vascular plants in the Experiment Forests of Kangwon National University. Resources vascular plants were composed of 98 families, 345 genera, 551 species, 2 subspecies, 88 varieties, 10 formae, and 2 hybrid, totaling 653 taxa. Among the investigated resources plants, Korean endemic plants and rare or endangered plants were distributed 20 taxa and 18 taxa, respectively. There were 27 taxa of Naturalized plants in this study area, which would have unpredictable influence on the natural ecosystem. The urbanized index(UI) of all over the investigated areas was about 12.4%. Useful resources plants were composed edible source(42.1%), medicinal source(33.8%), pasture source(28.8%), ornamental source(11.8%), timber source(5.2%), fiber source(1.4%), industrial source(1.1%). Vascular plants of unknown use were 140 taxa(21.4%).

• The Korean Journal of Ecology
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• v.22 no.1
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• pp.21-29
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• 1999

This study was carried out to clarify the syntaxonomy of the pine forest in Youngdong region by the phytosociological methods. As a result of the investigation of 62 quadrats, Pinus densiflora forest was classified into four subassociations: Typical subassociation, Quercus mongolica subassociation, Rhododendron mucronulatum subassociation, Rhus chinensis subassociation. Many differences in ecological characteristics such as species composition, stratum structure, vegetation coverage and of diameter at breast height(DBH) of class distribution were found among the communities. Soil properties of the pine forest on the study area was relatively poor compared with other pine forests, especially, soil pH was strongly acidic with 4.87. Soil conditions among the subassociations appeared different. Future succession of pine forest by the similarity index of communities was proposed. Estimated degree of green naturality for Typical subassociation and Q. mongolica subassociation correspond to 7th grade, and R. mucronulatum subassociation, 8-1st grade, and R. chinensis subassociation, 8-2nd grade.

• Korean Journal of Environment and Ecology
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• v.7 no.2
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• pp.192-206
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• 1994

The freshwater fish fauna of the Tokyusan National Park was censused during June 1993 to November 1993 at 9 sampling sites to establish baseline data for natural conservation program on the National Park. Seventeen species included 7 Korean endemic species and/or subspecies(Acheilognaths koreunus, Squazidus gracilis majimae, Microphysogobio yaluensis, Phoxinus kumganensis, Cobitis koreensis koreensis, Silurus microdorsalis and Odontobutis platycephala) belonging to 5 families were collected in this region. Sixteen species were found in Kumkang and 8 species were found in Naktongkang, however, common species were Squalidus gracilis majimae, Microphysogobio yaluensis, Puntungia herzi, Moroco oxycephalus, Zucco temminckii, Misgurnus anguillicaudatus and Odontobutis platycephala. Dominant species of this region were Moroco oxycephalus, Zacco temminckii, Odontobutis platycephala. The final aims of this study were not only accumulate baseline data on the osteology of Korean freshwater fishes which were collected at those streams during June 1993-November 1993 with soft X-ray radiography, but also evaluate the suitability of osteological analyses on the environmental damage to fish.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1444-1452
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• 2009

Probabilistic distribution functions based data generation method is very effective. Probabilistic distribution functions are defined under the assumption that daily routine contexts are mainly depended on a time-based schedule. However, daily life contexts are frequently determined by previous contexts because contexts have consistency and/or sequential flows. In order to refect previous contexts effect, a situation propagation network is proposed in this paper. As proposed situation propagation network make parameters of related probabilistic distribution functions update, generated contexts can be more realistic and natural. Through the simulation study, proposed context-data generation model generated general outworker's data about 11 daily contexts at home. Generated data are evaluated with respect to reduction of ambiguity and confliction using newly defined indexes of ambiguity and confliction of sequential contexts. In conclusion, in case of combining situation propagation network with probabilistic distribution functions, ambiguity and confliction of data can be reduced 6.45% and 4.60% respectively.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.5
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• pp.1012-1022
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• 1989

Numerical analysis has been performed on three-dimensional natural convection in inclined concentric annuli with the nonuniform temperature distribution of the inner cylinder. The governing equations are numerically solved by successive over-relaxation methods for various inclination angles at $R_{a}$=3*10$^{4}$, $P_{r}$=7.0 and $r_{1}$ / $r_{2}$=0.6. Temperature and Nusselt number distributions are obtained and calculated results are compared with those of published uniform temperature distributions. It is found that the mean Nusselt numbers for the nonuniform temperature distributions increase more than those for the uniform temperature distributions by about 9. 6% at .delta.= 0.deg., 7.5% at .delta. = 30.deg. and 4.6% at .delta. = 60.deg.. In the case of .delta. = 0.deg., the maximum local Nusselt numbers on the inner and outer cylinder walls show at .xi. = 0.5, 1.5 of .psio=100 .deg. and .xi. = 0.4, 1.6 of .psi. = 180 .deg.. But in the case of .delta. = 30.deg. and .delta. = 60.deg., the maximum local Nusselt numbers on the inner and other cylinder walls show at .xt. = 0.0 of .psi. = 180 .deg. and .xi. = 2.0 of .psi. = 180 .deg...

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.141-141
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• 2018

자연하천에 존재하는 식생은 동식물에게 주거지를 제공할 뿐만 아니라 영양염류 흡착 및 정화작용을 통해 수질을 개선시키는 역할을 한다. 이러한 식생하천에 오염물질이 유입될 경우 식생에 의한 흐름 교란 작용으로 인해 오염물의 확산거동에 큰 영향을 주게 된다. 본 연구에서는 식생하천에서의 오염물질 혼합특성을 분석하기 위해 식생모형 실험을 수행하였고, Fischer et al (1979)이 제시한 이론식을 실험결과에 적용하여 종분산계수를 산정하고자 한다. 본 연구에서는 자연하천을 재현하기 위해 실험수로에 수중식생 모형을 설치한 후 ADV-Vectrino유속계를 이용하여 유속을 측정하였으며 실험을 통해 식생흐름에서의 유속분포 자료를 취득하고 이를 바탕으로 종분산계수를 산정하였다. 먼저 수중 식생흐름에서 연직유속분포를 측정한 결과, 식생이 존재하는 바닥근처에서는 유속이 느리다가 비식생 구간으로 가면서 유속이 증가하는 분포를 나타낸다. 또한 이 설치된 테스트 구간에 밀도와 유량변화에 따른 케이스를 적용하여 비교 및 분석을 한 결과 식생 밀도를 고정시키고 유량을 증가 시켰을 때 식생구간과 식생이 없는 구간에서의 유속도 증가하는 경향을 보였으며, 유량을 고정시키고 식생의 밀도를 순차적으로 높였을 경우 식생구간에서의 유속이 점차적으로 줄어드는 경향을 보였다. 다음으로 분산계수를 결정하는 방법에는 농도자료를 이용하는 방법과 유속자료를 이용하는 방법이 있는데 본 연구에서는 유속자료를 Fischer et al. (1979)의 이론식에 적용하여 분산계수를 산정하는 방법을 적용하였다. Fischer et al. (1979)가 제시한 식에서 먼저 전단 유속 값을 산정하기 위해 벽법칙 (Karman, 1930), 레이놀즈 전단응력 그리고, 난류운동에너지 (Graf, 1998) 방법을 사용한 후 복잡한 난류 흐름에 적용하기 가장 적합하다는 난류운동에너지 방법을 적용하여 전단 응력이 가장 크게 나온 식생모델 끝단에서의 값을 사용하였다. 그 결과, 수중 식생이 존재하는 흐름에서 무차원화 시킨 종분산계수는 6.89-9.78로 나타났다, 이는 Elder (1959)의 수심 적분을 통해 제시한 종분산계수 값 5.93보다 크다. 즉, 수중 식생이 존재할 경우 종분산계수는 식생이 존재 하지 않을 때 보다 증가하는 것으로 보여 진다.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.440-440
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• 2015

최근 급증하는 기후변화 영향으로 인한 자연재해의 위험이 증대되고 있다. 이러한 자연재해 중 가뭄은 그 빈도수나 피해의 규모가 홍수보다 작아 관련된 연구가 제한적이므로 유역의 특성을 반영한 장 단기 유출특성의 면밀한 검토가 요구되며, 향후 이를 반영한 홍수유출모형의 개발이 필요하다. 본 연구에서는 유역 수자원산정의 기초연구로서 낙동강 내성천 유역을 대상으로 유역의 유출수문자료를 구축하고 장기기저흐름지수(BFI: Base Flow Index), 표면유출지수(1-Base Flow Index)를 산정하여 유역의 유출특성을 분석하였다. 내성천유역은 낙동강 상류유역으로 본류길이는 110.69km, 유역면적은 $1,815.28km^2$이며, 분수계의 능선부가 대체로 1,000m이상의 고도를 나타내고, 유역분지의 평균 해발고도는 318.2m이다. 또한 영주댐이 검설 중에 있으며, 향후 댐 건설이 수자원에 끼치는 영향등을 분석 할 수 있는 유역이다. 본 연구에서는 내성천 유역을 분석하기 위해서 8개의 수위관측지점을 선정한 후, 2001년부터 2012년 기간의 일 유량자료를 바탕으로 유출비를 산정하였다. 내성천 8개 소유역의 유역 장기유출비를 분석한 결과 기저흐름지수는 0.24~0.47, 표면유출지수는 0.53~0.76의 분포를 나타내었다. 표면유출비는 미호(0.76), 월호(0.53), 점촌(0.71)유역을 제외한 5개 유역에서 0.62~0.65의 분포를 나타내었으므로 낙동강 상류인 내성천유역의 표면유출비로 0.63을 제시할 수 있을 것으로 판단된다. 향후 다수의 낙동강유역을 추가분석하여, 낙동강유역의 고유 유출특성을 제시 할 수 있을 것으로 기대된다.

• Fire Science and Engineering
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• v.22 no.3
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• pp.221-227
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• 2008

In this study, the fire suppression characteristics of a water mist with natural wind in a road tunnel were calculated using the FDS(Fire Dynamic Simulation) code. In addition, the cooling and the chemical kinetic effects of water vapor on fire extinction ere investigated in a counterflow non-premixed flame using a detailed chemistry. As a result, the behavior of fire plume and the spray characteristics of water mist are modified remarkably with the increasing of wind velocity. In the case which is not the external natural wind, small droplets are more efficient in fire suppression than large droplets. However, the large droplets show better results on the fire suppression than the small droplets with the increasing of wind velocity. It can be estimated that the natural wind disturb the penetration of water droplets into the flame region and decrease the effect of oxygen dilution. Finally, it can be identified that the fire into the natural wind can be suppressed with smaller amount of $H_2O$ by flame stretching effect in the flame region than one in an enclosure, and the chemical kinetic effects of $H_2O$ on fire extinction are not affected significantly the velocity of natural wind.