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Application of Echo-Sounder Monitoring Technique as Ecological Impact Assessments of Fish on Artificial Weir Construction (인공보의 어류생태영향 평가를 위한 Echo-sounder 모니터링 기법 적용)

  • Han, Jeong-Ho;Lee, Jae Hoon;Choi, Ji-Woong;Lim, Byung Jin;Park, Jong-Hwan;An, Kwang-Guk
    • Journal of Environmental Impact Assessment
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    • v.21 no.6
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    • pp.859-877
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    • 2012
  • In this study, Echo-sounder($E_s$) monitoring methodology was applied to test environmental impacts of artificial weirs(SCW and JSW) in the Yeongsan River on fish community and habitat structures at first time, and was compared with conventional fish sampling methodologies($C_s$). For the Es monitoring in the fields, parallel transect methods was employed in determining the survey distance interval with every 125 m within the upper-lower 2 km of the weirs. Four different fish sampling gears such as casting nets, kick nets, fyke nets, and gill nets were used for applications of $C_s$ monitoring methodology. According to the Echo-sounder monitoring, fish density, expressed as a number of individuals per square meter, along the longitudinal axis of the weir was significantly greater(JSW, t = 3.506, n = 30, p < 0.001) in the down-river reach of the weir than in the up-river reach. Also, fish density along the vertical water column was highest at mid-depths of Seungchon weir, which has simple habitat substrates, while fish density was highest at hypolimnetic depth of Juksan weir. According to fish sampling by the $C_s$ methodology, the fish compositions decreased as the river goes upward, and significant differences(JSW, t = 0.248, n = 30, p < 0.05) in the compositions of fish species occurred between up-reach and down-reach of the weirs. The dominant species near the two weirs were Opsarichthys uncirostris amurensis, Hemiculter eigenmanni and Coilia nasus. Overall, our fish and habitat data, based on $E_s$ and $C_s$ monitoring methodologies, suggest that the weirs disturbed the rivers due to initial habitat disturbances by the weir constructions as well as the barrier roles of weirs on fish passage and migrations. More long-term scientific and systematic fish impact monitoring and assessments($E_s$ and $C_s$) are required in the future to predict changes of ecological structures and functions on the constructions of the weirs.

The analysis of the aspects of science writing in high school science textbooks based on the 2009 revised national curriculum (2009 개정 교육과정에 따른 고등학교 과학 교과서의 과학 글쓰기 제시 양상 분석)

  • Park, Kilsoon;Kang, Eugene;Kim, Jina
    • Journal of Science Education
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    • v.38 no.2
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    • pp.344-355
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    • 2014
  • The 2009 revised curriculum emphasizes science writing as a way to foster scientific thinking, creative thinking and communicative abilities. This research attempted to find out the aspects of science writing in science textbooks by analyzing seven versions of the 2009 revised science textbooks. The results of the analysis are as follows. First, it was found that the proportion of science writing pages is small and the amount of science writing differs a lot depending on the kind of textbook. Also, science writing is generally located in the wrap-up part of each unit, and the amount and the number of science writing vary substantially from unit to unit depending on the textbook. Second, it was found that 'scientific knowledge-explanation' statements have the largest proportion and 'STS-assertion' statements have the second largest proportion in terms of topics and styles of science writing in science textbooks. Some 'scientific knowledge-explanation' statements are not appropriate to foster scientific ability because they evaluate reading comprehension of the suggested passage as nonliterary writing, not the writing itself as a method to learn science. Third, it was found that there are many predicates that do not indicate a clear purpose of the science writing contained in science textbooks.

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Influences of Timber Harvesting Methods on Soil Disturbance (임목생산방법에 따른 토양교란 영향 평가)

  • Lee, Eunjai;Li, Qiwen;Eu, Song;Han, Sang-Kyun;Im, Sangjun
    • Journal of Korean Society of Forest Science
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    • v.106 no.2
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    • pp.204-212
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    • 2017
  • Soil disturbance caused by timber harvesting is widely recognized as a potential threat to forest utilization. The degree and extent of soil disturbance is believed to vary with respect to harvesting methods and logging machines. This study has conducted to assess the degree of soil disturbance associated with ground-based cut-to-length (GC) and cable yarding with whole tree (CW) harvesting methods. Soil disturbance was classified using a visual assessment of harvest unit. The properties of soils in different disturbance levels were also evaluated to understand the influence of timber harvesting on soil structure with soil core sampling method. The deep disturbance and soil compaction were observed in sites by 48% and 23% through harvesting areas for GC and CW logging methods, respectively. The results showed that logging machine and number of machine passage had significant influences on soil bulk density and porosity. Soil disturbance types such as rutted, slash cover, and compact were influenced by equipment travel trends in a GC method.

Design and Development of an EHR Platform Based on Medical Informatics Standards (의료정보 표준에 기반한 EHR 플랫폼의 설계 및 개발)

  • Kim, Hwa-Sun;Cho, Hune;Lee, In-Keun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.4
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    • pp.456-462
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    • 2011
  • As the ARRA enacted recently in the United States, the interest in EHR systems have been increased in the field of medical industry. The passage of the ARRA presents a program that provides incentives to office-based physicians and hospitals adapting the EHR systems to guarantee interoperability with various medical standards. Thanks to the incentive program, a great number of EHR systems have been developed and lots of office-based physicians and hospitals have adapted the EHR systems certified by CCHIT. Keeping pace with the rapid changes in the market of healthcare, some enterprises try to push in to the United States healthcare market based on the experience acquired by developing EHR systems for hospitals in Korea. However, the developed system must be customized because of the different medical environment between Korea and the United States. In this paper, therefore, we design and develop an integrated EHR platform to guarantee the interoperability between different medical information systems based on medical standard technologies. In the developed platform, an integrated system has been composed by integrating various basic techniques such as data transmission standards and its methods, medical standard terminologies and its usage, and knowledge management for medical decision-making support. Moreover, medical data can be processed electronically by adapting an HL7 interface engine and the terminologies for exchanging medical information and the standardization of medical information. We develop SeniCare, an EHR system for supporting ambulatory care of the office-based physicians, based on the platform, and we verify the usability of the platform by confirming whether SeniCare satisfies the criteria of "meaningful use" issued by CMS or not.

Systems for Production of Calves from Cultured Bovine Embryonic Cells (우 수정란의 배양세포들로부터 송아지 생산을 위한 체계)

  • ;N. L. First
    • Korean Journal of Animal Reproduction
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    • v.18 no.4
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    • pp.299-307
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    • 1995
  • The goal of cell stem cell technology is to produce a viable and genetically normal animal. To achieve this goal various laboratories have followed 2 different pathways beginning with either the culture of 1) single or pooled ICMs grown with or without a feeder layer or 2) single or pooled 16-20 cell stage embryos grown with a feeder layer. Also, thus far embryonic cell cultures or lines have been established by several methods including loose suspension culture for short-term cultures and more commonly murine or bovine fibroblast feeder layers for long-term culture. Pluripotent lines have been derived from 16-cell through blastocyst inner cell mass stages. The efficiency of establishing cell lines and cell proliferation apper to be affected by the number of cells or embryos starting the line. Most attempts to produce offspring from long term STO cell feeder layer cultured ICM or morulae derived ES cells have resulted in pregnancy failure in the first trimester when ES cells were used in cuclear transfer or have failed to retain ES cells in the progeny produced by chimerization. The exception is 1 chimeric fetus from use of morula ES cells in the chimerization with early embryonic cells. There is much to be learned yet about ES cell culture requirements for maintenance of totipotency. If bovine ES cell lines loose imprinting pattern and totipotency with long-term culture and passage as suggested for mouse ES cells, we may be limited to the use of short-term cultures for multiplication of embryos and efficient production of transgenic animals. No bovine ES cell system has yet met all of the criteria indicated for a totipotent ES cell line.

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Efficient Establishment of Presumptive Embryonic Stem Cells from Bovine Blastocysts by Exposure to Calcium Ionophore (Calcium Ionophore를 이용한 소 배반포로 부터의 배아주 유사세포의 효과적인 분리)

  • 김선욱;류재웅;이철상;한용만;박정선;유대열;이경광
    • Development and Reproduction
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    • v.3 no.1
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    • pp.45-51
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    • 1999
  • It is crucial to remove trophectoderm (TE) cells of blastocysts for an efficient isolation of pluripotent embryonic stem (ES)-like cells from bovine blastocysts. We evaluated the effectiveness of chemosurgery using calcium ionophore A23l87 (CIPA) by investigating the viability and pluripotency of ES-like cell lines isolated from in vitro-produced bovine blastocysts after CIPA treatment. The blastocysts treated with 50 $\mu$M CIPA for 25 min colonized most efficiently (51% of blastocysts) and developed to ES-like cell lines through 10 passages (4.8% of blastocysts) among CIPA-treated groups with different concentration and duration. In comparison with CIPA-untreated blastocysts, the colonization rate and overall viability of the CIPA-treated blastocysts were five times higher, suggesting that CIPA treatment condition defined in this study was highly efficient for establishing ES-like cell lines without apparent toxicity of CIPA. We evaluated in vitro pluripotency of the established three ES-like cell lines by examining alkaline phosphatase (AP) activity, capability of embryoid body formation, and chromosomal euploidity of the cells. Our cells showed a heterogeneous AP activity similarly to other reports. The cells were able to form simple embryoid bodies during suspension culture and majority of them showed a normal chromosome number of 60, the euploid chromosomal complement of bovine Therefore, our data suggest that CIPA treatment can be safely used for an efficient isolation of ES-like cell lines from bovine blastocysts.

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Fishing Mechanism of Pots and their Modification 3. Behavior of Conger Eel, Astroconger myriaster, to Net Pots (통발어구의 어획기구 및 개량에 관한 연구 3. 그물통발유에 대한 붕장어의 행동)

  • KIM Dae-An;KO Kwan-Soh
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.3
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    • pp.238-244
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    • 1990
  • The behavior of conger eel, Astroconger myriaste(Brevoort), to the net pots with baits was investigated alternately in two experimental water tanks. One of the pots being dropped on the tank bottom, the eels increased rapidly in number of touching the pot to show a maximum whithin 30 minutes and then decreased gradually. The enterings of eels into the pots were also made mainly within 30 minutes and easier in pots with lower entrances. But the complete enterings were decided by the passage of eel tails through the pot entrances and so the eels retreated frequently after attemping to enter the pots, especially in pots small in the interval between the entrances and the baits or in pots with flappers. However, most of enterings encouraged the touches and earlier enterings ascribed earlier production of maximum touch. The eels, if entered the pots without flappers, got out of the pots relatively easily and the getting-out was easier in pots with lower entrances. On the other hand, the eels entered the pot with flappers could not get out of the pots. A comparison between the circular and square pots gave that the guidance of eels to the entrances was easier in the former and the passing of eels through the entrances in the latter, not only at the inside of pots but also at the outside. The general behavior of eels in touching or entering the net pots in the above results was almost equal to that on the bamboo and plastic pots in the previous paper.

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A Basic Study on Proper Straight Route Distance under Marine Bridge using ES Model (ES모델을 이용한 해상교량 하부 적정 직선항로 길이에 대한 기초 연구)

  • Park, Young-Soo;Choi, Kwang-young;Park, Sang-Won
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.2
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    • pp.133-139
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    • 2018
  • Keeping a proper straight route length under the marine bridge is one of the important factors for the safe passage of ships. However, according to port and harbor design standards, there is only a constant guideline of 8 times the length of the marine bridge underpass. On this study, we used the ES model to determine the ratio of risk to the route width, traffic volume, the degree of curvature of the route, and the length of the straight route in order to derive the optimal straight route distance. As a result, the risk ratio decreased by 2.27% as the route distance increased from 3L to 10L when the degree of curvature of the route was $45^{\circ}$. The risk associated with curvature was found to be 4.83% when the bending degree was changed from $0^{\circ}$ to $45^{\circ}$ in the case of 3L length. In addition, it was confirmed that the risk ratio according to the degree of curvature of the route and the straight route was reduced by 1.45% at maximum under the condition that the width of the line was 400m and the number of the vessels generated per hour was 20. It was verified that a straight route distance more than a certain length is needed depending on the congestion degree and the degree of curvature of the route when constructing the marine bridge.

A Study on the Bird Community in Hallasan National Park (한라산국립공원의 조류군집에 관한 연구)

  • Chun, Byung-Sun;Yu, Jae-Pyoung;Paik, In-Hwan;Oh, Hong-Shik;Paek, Woon-Kee
    • Korean Journal of Environment and Ecology
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    • v.21 no.2
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    • pp.149-160
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    • 2007
  • This study was performed to clarify general characteristics of the bird community structure within the boundaries of Hallasan National Park. The surveys were made during April 2006 to February 2007, and the birds were identified and the individual number of those birds was counted up to 38 species and 2,323 individuals in total. Among the total 38 species, 27 residents, 6 summer visitors, 2 winter visitors and 8 passage birds were identified by migratory pattern categories. The most dominant species was Corvus macrorhynchos (14.81%), followed by the Hypsipetes amaurotis(12.66%), and the third was Carduelis sinica(10.33%), and next, Corvus corone (8.44%). About 31 species and 1,639 individuals of birds were sighted around Sallok road 1 (A), and 27 species and 693 individuals of birds were spotted around mountain trails (B), Consequently, it was found that [A] area abounds in more birds than [B] area. Species diversity (H') was distributed over the range of $1.34{\sim}2.56$ degrees in view of the surveyed areas by season. The maximum species diversity (2.56) was found in (A) area in the spring, and the minimum species diversity (1.34) was seen in [B] area in the winter. There are different distributional patterns of birds in terms of the altitude. It was also observed that there were differences in weather factors and food resources by the altitude.

Magnetic Resonance Imaging Patterns of Post-Operative Spinal Infection : Relationship between the Clinical Onset of Infection and the Infection Site

  • Kim, Seon-Jeong;Lee, Sang Hoon;Chung, Hye Won;Lee, Min Hee;Shin, Myung Jin;Park, Seoung Woo
    • Journal of Korean Neurosurgical Society
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    • v.60 no.4
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    • pp.448-455
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    • 2017
  • Objective : To investigate the magnetic resonance imaging (MRI) findings and the patterns of postoperative spinal infection according to the passage of time. Methods : Institutional review board approval was obtained, and informed consent was not obtained for the retrospective review of patients' medical records. A total of 43 patients (27 men and 16 women; mean age, 64) diagnosed with postoperative spinal infection were included in this study. We retrospectively reviewed the MRI findings and the medical records and categorized the infection sites based on MRI, i.e., anterior, posterior, and both parts. The duration of the clinical onset from surgery was divided, i.e., acute (${\leq}2weeks$), subacute (2-4 weeks), and late (>4 weeks). Results : Postoperative spinal infection was involved in the posterior part in 31 (72%), anterior part in two (4.7%), and both parts in 10 patients (23.3%). Abscess or phlegmon in the back muscles and laminectomy site were the most common MRI findings. The number of patients with acute, subacute, and late clinical onset were 35, two, and six, respectively (mean, 33.4 days; range, 1-730 days). The mean duration of the clinical onset was 12 days in the posterior part, 15.2 days in both parts, and 456.5 days in the anterior part. Conclusion : Postoperative spinal infection usually occurred within four weeks in the posterior part and over time the infection was considered to spread into the anterior part. For the evaluation of postoperative spinal infection, the posterior surgical field was more important than the vertebral body or the disc space on MRI.