• Applied Biological Chemistry
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• v.32 no.1
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• pp.14-22
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• 1989

Chemical composition of the oyster mushroom(Pleurotus spp.) at different cropping stage were analyzed. The contents of crude protein, soluble protein, reducing sugar, total sugar and crude fat in Pleurotus ostreatus 201 were a little higher than those of Pleurotus sajorcaju. The Component contents were not different from the first to the second flush, while the contents were slightly decreased from the third flush. A11 component contents were highest in $3{\sim}5cm$ pileus size, the contents were slightly decreased as pileus size increase to over $3{\sim}5cm$, except for reducing sugar. Crude fiber content in Pleurotus sajor-caju were a little more than Pleurotus ostreatus 201, and in course of increasing cropping time, ash contens of two strains were simmilar, and were decreased after the second flush. These component contents mere increased by the growth of the pileus. The sugars were identified as xylose, glucose, mannitol and trehalose in Pleurotus sajor-caju, and xylose, fructose, glucose, mannitol and trehalose in Pleurotus ostreatus 201, respectively. Mannitol and trehalose contents in Pleurotus sajor-caju were a little more than that in Pleurotus ostreatus 201. Glucose content of Pleurotus sajor-caju and Pleurotus ostreatus 201 was highest in $1{\sim}3cm$ pileus size, while other sugars in $3{\sim}5cm$ pileus size, and the sugar contents were decreased at over the above size of the pileus.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.21-37
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• 2010

The abiotic factors and the vegetation naturalness of the 13 tributary wetlands around Namgang-River were assessed to investigate the present state and to present the conservation counter plan for the wetland ecosystem of the tributaries. Assessment indices for the abiotic factors were estimated based on the dominant land use types of the riparian zone, ecological function of the upper levee, levee slope structure, artificiality and utilization intensity of the waterfront, artificiality of the revetment structure, diversity of the substrate, and severance of the transverse. The assessment index of Omi-cheon is the highest among 13 tributaries. The second was Banseong-cheon and third was Hyangyang-cheon, followed by Nabul-cheon and Yeongcheon-gang and Sugok-cheon, Jungchon- cheon, and Daegok-cheon in their order and Munsan-cheon got the lowest assessment index. Assessment indices for the vegetation naturalness were estimated based on the vegetation diversity, exotic species dominance, annual herb dominance, naturalness and peculiarity of the vegetation, and species diversity. The assessment index of Omi-cheon is the highest among 13 tributaries. The second was Sugok-cheon and third was Banseong-cheon, followed by Yeongcheon-gang, Jungchon- cheon, Jinae-cheon, Nabul-cheon, and Jisu-cheon in their order, and Yonga-cheon got the lowest assessment index. The grades of the stream naturalness were estimated based on the the naturalness indices for the abiotic factors and the vegetation naturalness. The grades of Omi-cheon is the highest among 13 tributaries as the grade I. Those of Banseong-cheon, Sugok-cheon, Yeongcheon-gang, Nabul-cheon and Jungchon-cheon, Hyangyang-cheon, Jinae-cheon, Jisu-cheon, Daegok-cheone, and Munsan-cheon and Doksan-cheon were grade II in their order, and Yonga-cheon got the lowest as the grade III. It was suggested that restoration of the simple and flat substrate, create the natural vegetation on the levee slope constructed with concrete or stone wall, and rehabilitation of the eco-bridge were demanded to improve the grades of the stream naturalness through the restoration of the tributaries for the diverse aquatic wildlife, high vegetation diversity and species diversity with the vegetation consisted of perennial herbs and trees.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.321-322
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• 2012

의료용 방사선 장비는 초기의 아날로그 방식의 필름 및 카세트에서 진보되어 현재는 디지털 방식의 DR (Digital Radiography)이 널리 사용되며 그에 관한 연구개발이 활발히 진행되고 있다. DR은 크게 간접방식과 직접방식의 두 분류로 나눌 수 있는데, 간접방식은 X선을 흡수하면 가시광선으로 전환하는 형광체(Scintillator)를 사용하여 X선을 가시광선으로 전환하고, 이를 Photodiode와 같은 광소자로 전기적 신호로 변환하여 방사선을 검출하는 방식을 말하며, 직접 방식은 X선을 흡수하면 전기적 신호를 발생 시키는 광도전체(Photoconductor)를 사용하여 광도전체 양단 전극에 고전압을 인가한 형태를 취하고 있는 가운데, X선이 조사되면 일차적으로 광도전체 내부에서 전자-전공쌍(Electron-hole pair)이 생성된다. 이들은 광도전체 양단의 인가되어 있는 전기장에 의해 전자는 +극으로, 전공은 -극으로 이동하여 아래에 위치한 Active matrix array을 통해 방사선을 검출하는 방식이다. 본 연구에서는 직접방식 X-ray 검출기에서 활용되는 a-Se을 ITO (Indium Thin oxide) glass 상단에 Thermal evaporation증착을 이용하여 두께 $50{\mu}m$, 33 넓이로 증착 시킨 다음, a-Se상단에 Sputtering증착을 이용하여 ITO를 11 cm, 22 cm, $2.7{\times}2.7cm$ 넓이로 증착시켜 상하부의 ITO를 Electrode로 이용하여 직접방식의 X-ray검출기 샘플을 제작하였다. 제작 과정 중 a-Se의 Thermal evaporation증착 시, 저진공 $310^{-3}_{Torr}$, 고진공 $2.210^{-5}_{Torr}$에서 보트의 가열 온도를 두 번의 스텝으로 나누어 증착 시켰다. 첫 번째 스텝 $250^{\circ}C$, 두 번째 스텝은 $260^{\circ}C$의 조건으로 증착하여 보트 내의 a-Se을 남기지 않고 전량을 소모할 수 있었으며, 스텝간의 온도차를 $10^{\circ}C$로 제어하여 균일한 박막을 형성 할 수 있었다. Sputtering증착 시, 저진공 $2.510^{-3}$, 고진공 $310^{-5}$에서 Ar, $O_2$를 사용하여 100 Sec간 플라즈마를 생성시켜 ITO를 증착하였다. 제작된 방사선 각각의 검출기 샘플 양단의 ITO에 500V의 전압을 인가하고, 진단 방사선 범위의 70 kVp, 100 mA, 0.03 sec 조건으로 X-ray를 조사시켜 ITO넓이에 따른 민감도(Sensitivity)와 암전류(Dark current)를 측정하였다. 측정결과 민감도(Sensitivity)는 X-ray샘플의 두께에 따른 $1V/{\mu}m$ 기준 시, 증착된 ITO의 넓이가 11 cm부터 22 cm, $2.7{\times}2.7cm$까지 각각 $7.610nC/cm^2$, $8.169nC/cm^2$, $6.769nC/cm^2$로 22 cm 넓이의 샘플이 가장 높은 민감도를 나타내었으나, 암전류(Dark current)는 $1.68nA/cm^2$, $3.132nA/cm^2$, $5.117nA/cm^2$로 11 cm 넓이의 샘플이 가장 낮은 값을 나타내었다. 이러한 데이터를 SNR (Signal to Noise Ratio)로 합산 하였을 시 104.359 ($1{\times}1$), 60.376($2{\times}2$), 30.621 ($2.7{\times}2.7$)로 11 cm 샘플이 신호 대 별 가장 우수한 효율을 나타냄을 알 수 있었다. 따라서 ITO박막의 면적이 클수록 민감도는 우수하나 그에 따른 암전류의 증가로 효율이 떨어짐을 검증 할 수 있었으며, 이는 ITO면적이 넓어짐에 따른 저항의 증가로 암전류에 영향을 끼침을 할 수 있었다. 본 연구를 통해 a-Se의 ITO 박막 면적에 따른 전기적 특성을 검증할 수 있었다.

• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.194-201
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• 2009

To evaluate the exposure of non-point source pesticide pollution in agricultural watershed and to investigate pesticide distribution and runoff from agricultural land, paddy field, upland and orchard, this experiment was carry out during crop growing seasons. The pesticide were detected twenty pesticides fungicide 4, insecticide 10, herbicide 6) in water of Neungchon agricultural watershed and detection concentrations were range 0.008${\sim}$7.59 ppb. Most of the detection pesticides were using pesticides to rice paddy fields to control fungi, insects, weeds. During the crop cultivation, the pesticide were detected total thirty pesticides by pepper field soil 6, orchard soil 4, sesame field soil 3 and rice paddy field soil 5, and pesticide concentrations were range 0.001${\sim}$0.109 ppm. Especially the herbicides were detected mainly in May and June in the stream water. The pesticide were detected thirty pesticides by fungicide 2, insecticide 6, herbicide 5 in water of Jungam Koseong agricultural watershed and detection concentrations were range 0.01${\sim}$7.21 ppb. In regard to the detected pesticides, the concentration of individual pesticides measured in surface water of the study areas never exceeded guidelines for agriculture chemicals concerning water quality-effluent from paddy fields in Japan (Katayama, 2003). Runoff rate of pesticides was range 0.07${\sim}$3.06 % from Kongju agricultural land to watershed after applied pesticides.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.628-635
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• 2014

The large amount of $CO_2$ emitted from mushrooms during incubation and developmental stages can be utilized in plant production systems as a $CO_2$ source. The objectives of this study were to measure the $CO_2$ emission and absorption rates of mushroom and lettuce, respectively, and to analyze the $CO_2$ concentrations at various ratios of mushroom and lettuce in a closed production system. The $CO_2$ emission rate of king oyster mushrooms (Pleurotus eryngii ( DC.) Qu$\acute{e}$l) and $CO_2$ absorption rate of lettuces (Lactuca sativa L. cv. Asia Heuk Romaine) were measured by using two closed acryl chambers ($1.0m{\times}0.8m{\times}0.5m$) in which indoor temperatures were maintained at $18^{\circ}C$ and $22^{\circ}C$, respectively. The lettuce was grown at a light intensity of PPF $340mol{\cdot}m^{-2}{\cdot}s^{-1}$ and with nutrient solution at EC $1.2dS{\cdot}m^{-1}$. The air was periodically circulated between the two chambers using a diaphragm pump. The $CO_2$ emission rate of the mushroom increased until the $15^{th}$ day after scratching (DAS) and then decreased. The rate also increased with increased indoor temperature. In particular, the $CO_2$ emission rate per fresh weight of fruit body increased by about 3.1 times after thinning compared to before thinning. In terms of $CO_2$ balance, the $CO_2$ emission rates from a bottle (950 mL) of the mushroom at 9, 12, and 14 DAS were equivalent to those of 3, 4.5, and 5.5 lettuce plants at 7, 10, and 12 DAT (days after transplanting), respectively. This work shows that balance in $CO_2$ concentration could be achieved using an appropriate ratio of the two crops in a closed production system.

• Journal of the Korean Geographical Society
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• v.31 no.2
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• pp.106-127
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• 1996

In Korea, modern geomorphology has developed as one of main subjects in geography, such as in Europe. Geomorphology is one of the most advanced specialties in the geography dicipline, since foundation of Korean Geographical Society in 1945. Untill 1960's study, first generation of the Korean geomorphologists trained the younger ones, together with energetic research activities. Their great works in education and research established the base of ulterier development of the geomorphology in Korea. Since 1970s, research manpower and quality has incresed rapidly, partly due to the various international activities and cooperations of Korean geomorphologists. Owing to above development, Korean geomorphologist was able to found "The Geomorphological Association of Korea" in 1990 and publish "Journal of GAK", since 1994. Furthermore, geomorphologists are playing important roles in interdisciplinary academic societies, such as "The Korean Quaternary Assocition". Still 1960s, our research had focused on the identification and interpretation of erosional surfaces in Korea Peninsular. Of course, W.M. Davis's "Geographical Cycle Theory" and L.C. King's "Pedimentation Theory" had a great influence on the Koerans' works. After 1970s, the study of erosional surface played the important role in setting up the morphoclimatic viewpoint and methodology. Research scope tend to be notably broad and various than it was untill 1960's. Disposotion of the scientific methods and techniques become more and more apparent. These trends of research has settled precise descreption and interpretation of actual landforms, based on the careful field works, scientific measuring, and analisis, rather than methodology focused on the particular master theories. Recent geomorphological researches show the scope from climatic geomorphology and Quaternary geomorphology to granite and limestone weathering, pedo-geomorphogenic environment and periglacial landforms, focused on the small-to-medium scales. And then there have been new trying to interprete erosional surfaces such as hillslopes and terraces. Also, studies of coastal and plain landforms have been successfully developed. Recent new trends show the quantitative and analytic modelling using field measurement and laboratory work, and study on the human impacts on the natural landforms.y on the human impacts on the natural landforms.

• Advances in pediatric surgery
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• v.8 no.1
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• pp.16-22
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• 2002

Between March 1999 and January 2000, 82 boys with the diagnosis of inguinal hernias (12 bilateral and 70 unilateral hernias), underwent Ultrasound (US) examination of both sides of the groin, a total of 164 inguinal imaging prior to surgery. The patients ages ranged from 3 days to 12 years with a mean of 32.6 months. Ninty four examinations were on the clinically symptomatic side and 70 were on the asymptomatic side. The US criteria for the diagnosis of an inguinal hernia were as follows: 1) visceral hernia, the presence of bowel loops, or omentum in the inguinal canal, 2) communicating hydrocele, the presence of fluid in the processus vaginalis, 3) widening of patent processus vaginalis at the level of internal inguinal ring. The width of patent processus vaginalis at the level of internal inguinal ring over 4 mm is considered an occult hernia. Among the 94 symptomatic groins, US findings showed 31 (33%) visceral hernias, 18 (19%) communicating hydroceles, and 38 (41%) widening of the internal inguinal ring, and 7 (7%) groins without abnormalities. In 70 asymptomatic groins, there were 4 (6%) visceral hernias, 5 (7%) communicating hydroceles, 11 (16%) widening of the internal inguinal ring, and 50 (70%) groins without abnormalities. Among the 70 asymptomatic groins there were US abnormalities in 20 (28%). One hundred and seven groins with positive US findings were surgically explored. Among 107 operated sites, the operative findings were compatible with the US diagnosis in 104, a sensitivity for US of 97.2%. In patients with US findings of widening of internal inguinal ring (>4 mm), there was patent processus vaginalis in 36 out of 38 symptomatic groins and 10 of 11 asymptomatic groins. The sensitivity of US to the operative findings in widening of internal inguinal ring was 93.8%. For visceral hernia and communicating hydrocele, the sensitivity of positive US findings was 100%. Ultrasonography for inguinal hernias appears to be a rapid, reliable, and noninvasive screening diagnostic tool with high positive specificity. Therefore, we recommend the use of US as a routine diagnostic tool in pediatric patients with inguinal hernias and hydroceles.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.96-106
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• 2008

The purpose of this study was to identify the actual conditions of operation in school and investigate the perceptions of science teachers and students regarding the 7th elective-centered curriculum of high school science subjects. For this study, a questionnaire survey was conducted for the selected subjects including 127 high school science teachers and 763 high school students in their third year who had experienced the 7th elective-centered curriculum. As a result of the study, concerning the way to present the elective subjects of science, many cases were the alternative way and the group-elective way in humanity courses while natural science courses had the alternative way and the free-elective way in most cases. In other words, in many cases, the right of elective was given within a limited range. The result of the investigation on science teachers' perceptions on the elective-centered curriculum was that negative views dominated as a whole. Especially, earth science teachers showed the most negative attitudes. The number of biology and chemistry teachers who supported students' right to opt subjects were lower than that of physics teachers and earth science teachers who were against it. To help students make a right choice, many viewed that the system of the college Scholastic Ability Test should be complemented in order to prevent any disadvantage to each elective subject or that it was necessary to have systematic and realistic career education. As the result of investigating the perception of high school students in their third year regarding the elective-centered curriculum, they were usually not very satisfied with it. As the reason for it, many said the selection right was limited. Many others also expressed that there were lack of public relations and education on subjects and careers. Based on these results, limits still exist in accepting all demands although there are a lot of efforts made to smoothly adjust supply and demand of science teachers as well as students' electives in the field of school. It is considered necessary to come up with counterplan and complements to prevent basic science from being neglected or lower academic achievement in the subject of science from happening, and at the same time to harmoniously deal with supply and demand of science teachers as well as the issues of students' demands given the actual conditions of school.

• Korean Journal of Agricultural Science
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• v.20 no.1
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• pp.25-33
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• 1993

This study was conducted to obtain necessary informations for improving of wildlife rearing management. The data was gathered by surveying with questionaire. One hundred and eighty farmers which was 60 of deer and pheasant, 30 of wild boar and fox rearing farmers respectively were investigated during the summer in 1992. The results of this study are as follows : 1. Most of managers considered their rearing as a side job but agriculture was appointed as a main job from most of them except wild boar managers. 2. The major cost items were breeding stock and feeding which occupied over than half. 3. The yearly profit was the highest in deer(25.5%) but the lowest in wild boar(10.3%). 4. The break-even point was the highest in wild boar(24 mil. won) but the lowest in pheasant(7.3 mil. won). 5. The optimum sales scale for a year was deer(11 heads), Pheasant(1,027 heads), Wild boar(69 heads) and Fox (102 heads).

• Journal of Wetlands Research
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• v.5 no.2
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• pp.15-32
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• 2003

The ecological study on seven wetlands of Haman area in Kyungsangnamdo, Korea, was carried out. In especial, the biological data of the sites were unknown. In this study, water quality including water temperature, pH, DO, COD, T-N, T-P, SS were tested. On the survey of plants and animals, vegetation and flora were investigated and the fauna of insects, fish, and amphibians were studied on each wetland. Water of wetland Oksu was heavily polluted and wetlands Pyungy and Dodulyangy were relatively clean. The water pollution was most severe in winter at all of the wetlands. Plant communities were classified into 9 natural communities and 1 artificial community. On the vegetation, wetland Sugok showed the highest plant taxa, and 41 families, 78 species and 16 varieties were classified. There was remarkable difference in number of plant taxa. The difference may be caused by the variances of wetland sizes, the influence from terrestrial environment. Wetland Sugok showed most rich insect fauna, and 10 orders, 76 families 224 species and 1082 individuals were identified. The species diversity was 2.05 and the species richness was 73.49. Wetland Ddun showed poor insect fauna, and 6 orders, 23 families, 29 species and 81 individuals were identified. Total collected fish were 4 orders, 7 families and 11 species. The fish fauna was most rich in wetlands Oksu and Pyungy, but poor in wetland Unan. Total collected amphibians were 2 orders, 3 families and 4 species.