• Journal of Energy Engineering
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• v.28 no.3
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• pp.1-9
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• 2019

A major stress determining the remaining life of the tube in feedwater heater of fossil fuel power plant is hoop stress by the internal pressure. However, thermal stress due to temperature difference across the wall thickness also contributed to reduce the remaining life of the tube. Therefore, thermal loading must be considered even though the contribution of internal pressure loading to the stresses of the tube was known to be much higher than that of the thermal loading. In this study, thermal stress of the tubes in the de-superheating zone was estimated, which was generated due to the temperature difference across the tube thickness. Analytic equations were shown for determining the hoop stress and the radial stress of the tube with uniform thinning and for the temperature across the tube thickness. Accuracy and effectiveness of the analytic equations for the stresses were verified by comparing the results obtained by the analytic equations with those obtained from finite element analysis. Using finite element analysis, the stresses for eccentric thinning were also determined. The effect of heat transfer coefficient on thermal stress was investigated using series of finite element analyses with various values of heat transfer coefficient for both inner and outer surface of the tube. It was shown that the effect of heat transfer coefficient at outer surface was larger than that of heat transfer coefficient at inner surface on the thermal stress of the tube. Also, the hoop stress was larger than the radial stress for both cases of uniformly and eccentrically thinned tubes when the thermal loading was only considered without internal pressure loading.

• Parasites, Hosts and Diseases
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• v.28 no.1
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• pp.1-10
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• 1990

To establish an animal model of intracranial sparganosis, the fate and behavior of the experimentally inoculated spargana were observed. A total of 102 scolices of spargana were injected into 22 cat brains, and the cats were sacrificed at 2 weeks, 1 month, 3 months and 6 months after the inoculation. Neurosparganosis was established in 77% of the cats. Of 43 recovered worms,19 (44%) were located in the subdural or subarachnoid space,16 (37%) in the brain Parenchyme, and 2 (5%) in the lateral ventricle. One was detected at the diploic space of the skull and 5 were outside the cranial cavity. All but one were alive, and had grown tails. They were distributed in the brain parenchyme randomly. There was no place which they could not invade. No adult was found in the intestine. Cerebrospinal fluid (CSF) was collected before inoculation, 1 week, 2 weeks, 1 month, 3 months and 6 months after inoculation. The level of anti-sparganum IgG antibody in CSF measured by ELISA began to increase above the criteria of positivity 1 month after inoculation. Three months after inocula- tion, the values markedly increased. The present findings reveal that intracranial inoculation of spargana into the brains of cats would be a good animal model of experimental neurosparganosis.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.895-905
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• 2004

Herb found in the farm of Korea were classified into 3 divisions, 5 classes, 31 orders, 51 families, 134 genera and 226 kinds. In the taxon of family, labiatae, compositae and umbelliferae have larser number of herbs than another families. In the taxon of genus, Rosa (34 kinds), Mentha (8), Thymus (7), Pelargonium (6), Salvia (6), Lavandula (5), Citrus (4), Ocimum (4), Allium (4) in order contain many species. In the geographical floristic regions, Holarctic were 149 kinds, and next came Paleotropical of 26 kinds, Neotropical of 18 kinds, Capetown of 8 kinds, and Australian of 6 kinds in order. Plants growing naturally over 3 geographical region were 4 kinds including Passiflora caerulea. And 166 kinds were growing in the only 1 geographical region. Among the all farms, (1) farm (in Cheongwon) were highest number of 137 kinds. On the other hand, (3) farm (in Cheongsong) were lowest number of 59 kinds. Herb cultivating in all farms were 37 kinds including Pelargonium crispum. Among these, plants of 24 kinds belong to the labiatae family. Also, herb cultivating in the only 1 farm were 50 kinds including Humulus lupulus. About the numbers of usage of herb, the first in numbers was for food $(54.4\%,\;122\;kinds)$ including Ginkgo biloba, the second for medicinal purpose $(39.8\%,\;90\;kinds)$ including Equisetum arvense, the third for cosmetic $(15.9\%,\;36\;kinds)$, th fourth for flavor $(14.2\%,\;32\;kinds)$, the next for perfume $(12.4\%,\;28\;kinds)$, the next for dye $(10.8\%,\;23\;kinds)$, the next for insecticide $(6.6\%,\;15\;kinds)$, the next for ornament $(1.8\%,\;4\;kinds)$, the last for antiseptic $(0.9\%,\;2\;kinds)$.

• Journal of the Korean association of regional geographers
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• v.17 no.2
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• pp.150-166
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• 2011

This study aims to investigate the differences of synoptic characteristics and frontal structures over East Asia according to the main path types of water vapor flux (WVF) of 850hPa surface in cases of the heavy rainfall in the south coastal region of Korea during the Changma season (June and July), In the cases of type A in which the main path of WVF is running from the South china Sea via the South china to the South Sea of Korea, the North Pacific subtropical anticyclone (NPSA) expands to the South China and strong cyclones appear in the Yellow Sea. In cases of type B and C in those the main paths of WVF are running from the South China Sea via the Western Pacific Ocean near Taiwan to the South Sea and from the Western North Pacific Ocean to the South Sea respectively, tropical cyclones appear frequently near Taiwan and the NPSA shifts northward. In the case of type D in which the main path of WVF appear only near the South Sea, strong cyclones appear near the Yellow Sea. In all cases upper jets are intensified in the northern part of the heavy rainfall region and low-level jets appear near the main paths of WVF. In the view of frontal structure, deep active-type of the Changma front is identified in most cases of all types. In this point the Changma season is different from the Baiu season in Western Japan where many cases of shallow active-type of the Baiu front appear.

• Journal of the Korean Solar Energy Society
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• v.31 no.3
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• pp.8-16
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• 2011

The objective of this study is to analyze the characteristic of thermal environment in the summer season by conducting the field observation of temperature, relative humidity, and globe temperature in some parts of the city. Observation point was divided to a densely populated area, a residential area, a green area, a waterfront green area and a suburban district by the distribution ratio of green area. In this study, the correlation between maximum temperature and globe temperature, study on index for intensity of the tropical night and the temperature distribution characteristic of measurement points by the distribution ratio of green area were analyzed. The results of this study are as follows. (1) The difference between temperature and globe temperature by the distribution ratio of green area is confirmed. The difference of nighttime is more clearly that of daytime. (2) The average temperature and globe temperature of the densely populated area($29.2^{\circ}C$, $33.7^{\circ}C$) are higher than that of the waterfront green area($27.9^{\circ}C$, $32.0^{\circ}C$) by $1.3^{\circ}C$ and $1.7^{\circ}C$, respectively. (3) The number of tropical nights has different days of tropical nights by the distribution ratio of green area of 17days for the Daegu weather station, 14days for adensely populated area, 14days for a residential area, 6days for a green area, 2days for a waterfront green area, and 2days for a suburban district. (4) The results of the slope of trend line for the effects of the temperature on globe temperature change and the intercept for the size of the impact of radiant energy gained around by the analysis of the correlation between the maximum temperature and globe temperature can be utilized objective evaluation index of the each point's artificial effects.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.76-76
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• 2002

무주나무(Lasianthus japonicus Miquel)는 일본, 대만, 중국 등에 분포하고 열대 및 아열대의 상록활엽수림에서만 자라는 것으로 알려져 있으며, 우리나라에는 제주도 남쪽계곡에만 분포하는 희귀식물이다. 무주나무는 현재 환경부 지정 보호야생식물로 보호되고 있으나 개체특성 및 자생지에 대한 정확한 조사가 이루어진 바 없다. 본 연구는 무주나무의 자생지 현황과 생육특성을 파악하고자 실시하였다. 무주나무의 자생지는 제주도 남제주군 남원읍 하례리 해발 250m의 계곡 동사면과 서귀포시 돈네코 계곡의 해발 350 m 계곡의 서사면 등 2개소로 확인되었다. 자생지별 개체수는 남원읍 하례리 4개체, 서귀포시 돈네코계곡 5개체 등 총 9개체에 불과하였다. 자생지는 계곡의 상록수림 하부에 바위 위 부엽토나, 습한 계곡 사면이었으며, 교목층에는 구실잣밤나무, 비쭈기나무, 황칠나무, 동백나무 등이 우점하고, 관목층에는 사스레피나무, 백량금, 산호수 등이 우점하는 상록활엽수림이었다. 분포 개체의 수고는 최소 0.4 m, 최대 1.55 m로 평균 1.5 m 였다. 생장특성을 조사한 결과 줄기는 어릴 때는 사각형이지만 점차 원형으로 되며, 일정한 마디가 있고 털이 없으며, 잎은 대생하고, 혁질이며, 중륵과 측맥이 뚜렷한 특성을 갖고 있었다. 열매는 장과형으로 성숙 시에는 남색이며 털이 없으며, 직경 약 6-7 mm, 4-5개의 종자가 들어 있었다. 종자는 반달형이며, 3개의 홈이 지는 특성을 갖고 있었다. 현재의 자생지는 자연적인 요인으로서 토양유실이 심하게 일어나고 있는 지역이었으며, 교목 또는 다른 관목에 의한 피압으로 무주나무의 생장에 부적절한 환경으로 판단되었다. 따라서 자생지의 적절한 식생관리와 지속적인 자생지 조사 및 자생지외 보존에 관한 연구가 이루어져야할 것으로 생각된다.$I_{NO}$ 가 죽절초를 제외한 3종에서 여름철 낮시간에 증가하였다. 겨울철의 O-J-I-P곡선은 모든 종에서 낮시간에 다소 낮아지지만 큰 변화는 없었다. 그리고, 문주란, 박달목서, 파초일엽에서 $\psi$o/(1-$\psi$o)가 낮시간에 다소 증가하였다. 이로부터 P $I_{NO}$ , SF $I_{NO}$ , $\psi$o/(1-$\psi$o)등의 변수는 식물의 활력도를 검정하는 지표로 활용될 가능성이 높다고 할 수 있다.irc}C$) 까지 동시에 냉각된 사실을 지시한다. 각섬석 편암내의 각섬석들은 복잡한 40Ar/39Ar 연대를 보여주며 일부가 평형연대를 보여주지만 특별한 의미 부여가 힘들다.해예방행동을 촉구하는 등의 효과도 높은 것으로 예방의학적인 유용성이 크다고 볼 수 있다. 미침을 알 수 있었다. 대두 단백질로 코팅된 golden delicious는 상온에서60일 동안 보관하였을 경우, 사과표피의 색도 변화를 현저히 지연시킴을 확인하였다. 또한 control과 비교하여 성공적으로 사과에 코팅하였으며, 상온에서 보관하여을 때 사과의 품질을 30일 이상 연장하는 효과를 관찰하였다. 이들 결과로부터 대두단백질 필름이 과일 등의 포장제로서 이용할 가능성을 확인하였다.로 [-wh] 겹의문사는 복수 의미를 지닐 수 없 다. 그러면 단수 의미는 어떻게 생성되는가\ulcorner 본 논문에서는 표면적 형태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$ elements)로 가정한다. 즉, [+wh] 의미의 겹의문사는 동일한 구성

• Parasites, Hosts and Diseases
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• v.25 no.1
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• pp.51-58
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• 1987

Tegumental ultrastructures of Echinochasmus japonicus were observed by scanning electron microscopy. The worms were recovered from albino rats which were experimentally infected with the metacercariae obtained from Pseudorasbora parva. Followings are summarized findings. 1. The worms were minute and plumpy gourdshaped with attenuated anterior and round posterior end. The tegument of whole body was wrinkled transversely and covered with cobblestone-like cytoplasmic processes. 2. Head crown was armed with 24 collar spines which were embedded in cytoplasmic pockets. The spines were arranged in a row with an interruption at dorsomedian line, however, the 2nd and the 4th spines were outstretched more than others. Oral and ventral suckers were muscular with numerous type II sensory papillae, and genital pore opened between the two suckers. 3. Tegumental spines were spade-shaped with broad base and pointed tip. They were compact in ventra-lateral tegument or dorsal surface of anterior body. They were not found between the two suckers and dorsal surface of posterior body. 4. Two types of sensory papillae, uni-ciliated (Type I) and roundly swollen sensory papillae (Type II), were observed. The type I papillae were chiefly distributed on ventral surface of tegument and type II were on the lips of suckers. Arrangement of collar spines, shape and distribution of tegumental spines or sensory papillae are regarded as characteristic features of E. japonicus.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.215-220
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• 2023

A recent discovery of drywood termites (Cryptotermes domesticus) in a residential facility in Seoul has raised significant concern. This exotic insect species, which can damage timber and wooden buildings, necessitates an immediate investigation of potential infestation. In this study, we assessed the climatic suitability for this termite species using a species distribution modeling approach. Global distribution data and bioclimatic variables were compiled from published sources, and predictive models for climatic suitability were developed using four modeling algorithms. An ensemble prediction was made based on the mean occurrence probability derived from the individual models. The final model suggested that this species could potentially establish itself in tropical coastal regions. While the climatic suitability in South Korea was generally found to be low, a careful investigation is still warranted due to the potential risk of colonization and establishment of this species.

• Parasites, Hosts and Diseases
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• v.30 no.2
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• pp.65-74
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• 1992

The tegumental ultrastructure of juvenile and adult Echinostoma cinetorchis (Trematoda: Echinostomatidae) was observed by scanning electron microscopy. Three-day (juvenile) and 16-day (adult) worms were harvested from rats (Sprague-Dawley) experimentally fed the metacercariae from the laboratory-infected fresh water snail, Hippeutis cantori. The worms were fifed with 2.5% glutaraldehyde, processed routinely, and observed by an ISI Korea DS-130 scanning electron microscope. The 3-day old juvenile worms were elongated and ventrally curved, with their ventral sucker near the anterior two-fifths of the body. The head crown was bearing 37∼38 collar spines arranged in a zigzag pattern. The lips of the oral and ventral suckers had 8 and 5 type II sensory papillae respectively, and bewteen the spines, a few type III papillae were observed. Tongue or spade-shape spines were distributed anteriorly to the ventral sucker, whereas peg-like spines were distributed posteriorly and became sparse toward the posterior body. The spines of the dorsal surface were similar to those of the ventral surface. The 16-day old adults were leaf-like, and their oral and ventral suckers were located very closely. Aspinous head crown, oral and ventral suckers had type II and type III sensory papillae, and numerous type I papillae were distributed on the tegument anterior to the ventral sucker. Scale-like spines, with broad base and round tip, were distributed densely on the tegument anterior to the ventral sucker but they became sparse posteriorly. At the dorsal surface, spines were observed at times only at the anterior body. The results showed that the tegument of E. cinetorchis is similar to that of other echinostomes, but differs in the number and arrangement of collar spines, shape and distribution of tegumenal spines, and type and distribution of sensory papillae.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.2
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• pp.1-16
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• 2017

This study was conducted to analyze the urban heat island(UHI) intensity of South Korea by using Moderate Resolution Imaging Spectroradiometer(MODIS) satellite imagery. For this purpose, the metropolitan area was spatially divided according to land cover classification into urban and non-urban land. From the analysis of land surface temperature(LST) in South Korea in the summer of 2009 which was calculated from MODIS satellite imagery it was determined that the highest temperature recorded nationwide was $36.0^{\circ}C$, lowest $16.2^{\circ}C$, and that the mean was $24.3^{\circ}C$, with a standard deviation of $2.4^{\circ}C$. In order to analyze UHI by cities and counties, UHI intensity was defined as the difference in average temperature between urban and non-urban land, and was calculated through RST1 and RST2. The RST1 calculation showed scattered distribution in areas of high UHI intensity, whereas the RST2 calculation showed that areas of high UHI intensity were concentrated around major cities. In order to find an effective method for analyzing UHI by cities and counties, analysis was conducted of the correlation between the urbanization ratio, number of tropical heat nights, and number of heat-wave days. Although UHI intensity derived through RST1 showed barely any correlation, that derived through RST2 showed significant correlation. The RST2 method is deemed as a more suitable analytical method for measuring the UHI of urban land in cities and counties across the country. In cities and counties with an urbanization ratio of < 20%, the rate of increase for UHI intensity in proportion to increases in urbanization ratio, was very high; whereas this rate gradually declined when the urbanization ratio was > 20%. With an increase of $1^{\circ}C$ in RST2 UHI intensity, the number of tropical heat nights and heat wave days was predicted to increase by approximately five and 0.5, respectively. These results can be used for reference when predicting the effects of increased urbanization on UHI intensity.