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Sensitivity of Simulated Water Temperature to Vertical Mixing Scheme and Water Turbidity in the Yellow Sea (수직 혼합 모수화 기법과 탁도에 따른 황해 수온 민감도 실험)

  • Kwak, Myeong-Taek;Seo, Gwang-Ho;Choi, Byoung-Ju;Kim, Chang-Sin;Cho, Yang-Ki
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.3
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    • pp.111-121
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    • 2013
  • Accurate prediction of sea water temperature has been emphasized to make precise local weather forecast and to understand change of ecosystem. The Yellow Sea, which has turbid water and strong tidal current, is an unique shallow marginal sea. It is essential to include the effects of the turbidity and the strong tidal mixing for the realistic simulation of temperature distribution in the Yellow Sea. Evaluation of ocean circulation model response to vertical mixing scheme and turbidity is primary objective of this study. Three-dimensional ocean circulation model(Regional Ocean Modeling System) was used to perform numerical simulations. Mellor- Yamada level 2.5 closure (M-Y) and K-Profile Parameterization (KPP) scheme were selected for vertical mixing parameterization in this study. Effect of Jerlov water type 1, 3 and 5 was also evaluated. The simulated temperature distribution was compared with the observed data by National Fisheries Research and Development Institute to estimate model's response to turbidity and vertical mixing schemes in the Yellow Sea. Simulations with M-Y vertical mixing scheme produced relatively stronger vertical mixing and warmer bottom temperature than the observation. KPP scheme produced weaker vertical mixing and did not well reproduce tidal mixing front along the coast. However, KPP scheme keeps bottom temperature closer to the observation. Consequently, numerical ocean circulation simulations with M-Y vertical mixing scheme tends to produce well mixed vertical temperature structure and that with KPP vertical mixing scheme tends to make stratified vertical temperature structure. When Jerlov water type is higher, sea surface temperature is high and sea bottom temperature is low because downward shortwave radiation is almost absorbed near the sea surface.

Cross-Sectional Item Response Analysis of Geocognition Assessment for the Development of Plate Tectonics Learning Progressions: Rasch Model (판구조론의 학습발달과정 개발을 위한 지구적 인지과정 평가의 횡단적 문항 반응 분석: Rasch 모델)

  • Maeng, Seungho;Lee, Kiyoung
    • Journal of The Korean Association For Science Education
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    • v.35 no.1
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    • pp.37-52
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    • 2015
  • In this study, assessment items to examine geocognition on plate tectonics were developed and applied to middle and high school students and college students. Conceptual constructs on plate tectonics are Earth interior structure, specific geomorphology, and geologic phenomena at each plate boundary. Construct for geocognition included temporal reasoning, spatial reasoning, retrospective reasoning, and system thinking. Pictorial data in each item were all obtained from GeoMapApp. Students' responses to the items were analyzed and measured cross-sectionally by Rasch model, which distinguishes persons' ability levels based on their scores for all items and compared them with item difficulty. By Rasch model analysis, Wright maps for middle and high school students and college students were obtained and compared with each other. Differential Item Functioning analysis was also implemented to compare students' item responses across school grades. The results showed: 1) Geocognition on plate tectonics was an assessable construct for middle and high school students in current science curriculum, 2) The most distinguished geocognition factor was spatial reasoning based on cross sectional analysis across school grades, 3) Geocognition on plate tectonics could be developed towards more sophisticated level through scaffolding of relevant instruction and earth science content knowledge, and 4) Geocognition was not a general reasoning separated from a task content but a content-specific reasoning related to the content of an assessment item. We proposed several suggestions for learning progressions for plate tectonics and national curriculum development based on the results of the study.

The Relation of Bipolar Tendency with Type A Behavior Pattern, Perceived Stress, and Lifestyle:Comparison between Mood Disorder Questionnaire Positive and Negative Respondents (양극성 경향과 스트레스 취약성:기분장애설문지 양성 반응군과 음성 반응군에서 지각된 스트레스, A형 행동, 그리고 생활습관의 비교)

  • Kim, Byung-Su;Kim, Seong-Yoon;Choe, Jae-Won;Joo, Yeon-Ho;Yoon, Dae-Hyun;Han, Nae-Jin;Kim, Yoo-Shin;Kim, Seon-Ok
    • Korean Journal of Psychosomatic Medicine
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    • v.18 no.1
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    • pp.19-29
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    • 2010
  • Objectives:Authors hypothesized that bipolar tendency of non-psychiatric person would be associated with stress vulnerability. To test the hypothesis, we compared perceived stress level, Type A Behavioral Pattern (TABP) and unhealthy lifestyle between person with and without bipolar tendency. Methods:The study cohort consisted of 1987 subjects without past and current psychiatric history. In this study, bipolar tendency was determined by MDQ response which requires endorsement of at least 7 of the 13 "yes or no" questions. We compared the scores of Perceived Stress Scale, A/B lifestyle questionnaire, and unhealthy lifestyle(alcohol, smoking, lack of exercise, irregular meal) between MDQ positive and negative respondents. Results:We identified the bipolar tendency group determined by the MDQ positive response were 329 subjects(16.6%). The overall score of the bipolar tendency group was significantly high on the A/B lifestyle questionnaire compared to the non-bipolar tendency group(125.4 vs. 115.9, p<0.001), and the rate of the subjects defined as TABP was also significantly high(41.3% vs. 30.1%, p<0.001). In comparison of subjectively perceived stress level, the bipolar tendency group was observed to be significantly higher than the non-bipolar tendency group (18.5% vs. 16.5%, p<0.001). The bipolar tendency group was significantly higher than the non-bipolar tendency group on the rate of answering:'irregular eating habit' (20.1% vs. 14.3%, p=0.002), '4-or-more-times alcohol intake per week' (29.8% vs. 16.5%, p<0.001), 'currently smoking' (41.9% vs. 23.0%, p<0.001), '2-or-less-times physical exercises per week' (63.2% vs. 55.1%, p=0.007). Conclusion:By clinical diagnosis, even a person who does not meet the criteria of bipolar disorder has a high risk of stress-related behavioral pattern, and perceived stress when possessing bipolar tendencies such as the (hypo) maniac tendency or affective instability. Such individual has significantly higher risk of having unhealthy life-style such as smoking, drinking, irregular eating habit and lack of exercise compared to non-bipolar tendency group. Since these risk factors lead to increase the risk of obesity, metabolic syndrome, diabetes, and cardiovascular diseases, the individual with the bipolar tendency requires a more effort to manage stress and to maintain healthy lifestyle.

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A preliminary numerical analysis on the behaviour of tunnel under construction in fracture zone considering seismic load (지진 하중을 고려한 단층파쇄대에서의 시공 중 터널 거동 분석에 관한 수치해석적 연구)

  • Oh, Dong-Wook;Hong, Soon-Kyo;Kim, Dae-Kon;Lee, Yong-Joo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.21 no.2
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    • pp.279-299
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    • 2019
  • Recently occurred earthquake Gyeongju and Pohang served as a momentum to remind that Korean peninsular is not a safety zone from earthquake anymore. The importance of seismic design, therefore, have been realized and researches regarding design response spectrum have been actively carried out by many researchers and engineers. Current tunnel seismic design method is conducted to check safety of tunnel structure by dynamic numerical analysis with condition of completed lining installation, so, it is impossible to consider safety of tunnel behavior under construction. In this study, therefore, dynamic numerical analysis considering seismic wave propagations has been performed after back analysis using results from field monitoring of tunnel under construction in fractured zone and 1st reinforcement (shotcrete, rockbolt) behaviour are analyzed. Waves are classified by period characteristic (short and long). As a result, the difference depending on period characteristic is minor, and increasements of displacement are obtained at crown displacement due to seismic wave is 28~31%, 14~16% at left side of tunnel in the fractured zone, 13~27% at right side of tunnel in the bed rock, respectively. In case of shotcrete axial force is increased 113~115% at tunnel crown, 102% at left side, 106~110% at right side, respectively. Displacement and axial force of rockbolts which are selected by type of anchored grounds (only fractured zone, fractured zone and bed rock, only bedrock) are analyzed, as a result, rockbolt which is anchored to fractured zone and bed rock at the same time are weaker than any other case.

Analysis of Climate Change Adaptation Researches Related to Health in South Korea (한국의 건강 분야 기후변화적응 연구동향 분석)

  • Ha, Jongsik
    • Journal of Climate Change Research
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    • v.5 no.2
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    • pp.139-151
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    • 2014
  • It is increasingly supported by scientific evidence that greenhouse gas caused by human activities is changing the global climate. In particular, the changing climate has affected human health, directly or indirectly, and its adverse impacts are estimated to increase in the future. In response, many countries have established and implemented a variety of mitigation and adaptation measures. However, it is significant to note that climate change will continue over the next few centuries and its impacts on human health should be tackled urgently. The purpose of this paper is to examine domestic policies and research in health sector in adaptation to climate change. It further aims to recommend future research directions for enhanced response to climate change in public health sector, by reviewing a series of adaptation policies in the selected countries and taking into account the general features of health adaptation policies. In this regard, this study first evaluates the current adaptation policies in public health sector by examining the National Climate Change Adaptation Master Plan(2011~2015) and Comprehensive Plan for Environment and Health(2011~2020) and reviewing research to date of the government and relevant institutions. For the literature review, two information service systems are used: namely, the National Science and Technology Information Service(NTIS) and the Policy Research Information Service & Management(PRISM). Secondly, a series of foreign adaptation policies are selected based on the global research priorities set by WHO (2009) and reviewed in order to draw implications for domestic research. Finally, the barriers or constraints in establishing and implementing health adaptation policies are analyzed qualitatively, considering the general characteristics of adaptation in the health sector to climate change, which include uncertainty, finance, technology, institutions, and public awareness. This study provides four major recommendations: to mainstream health sector in the field of adaptation policy and research; to integrate cross-sectoral adaptation measures with an aim to the improvement of health and well-being of the society; to enhance the adaptation measures based on evidence and cost-effectiveness analysis; and to facilitate systemization in health adaptation through setting the key players and the agenda.

Understanding the Access and Benefit-Sharing of Genetic Resources for Environmental Ecology Researchers (나고야의정서 이행에 따른 ABS 체계의 이해와 환경생태분야 연구자의 대응방안)

  • Lee, Jonghyun;An, Minho;Chang, YounHyo
    • Korean Journal of Environment and Ecology
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    • v.35 no.4
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    • pp.336-346
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    • 2021
  • The enforcement of the Nagoya Protocol, which regulates the acquisition and use of genetic sources, an essential material for biotechnology R&D, has imposed a burden for additional documentation works to researchers. In the past, countries regarded genetic resources as a common human heritage and thus allowed researchers to use them freely. However, they can no longer afford the luxury of such freedom now since many countries are introducing new laws and regulations on the acquisition and use of the resources as the Nagoya Protocol recognizes the exclusive ownership of genetic resources. Therefore, Korea, which is highly dependent on foreign genetic resources, needs a more systematic response. This paper aims to review the key contents of the Nagoya Protocol to raise awareness among domestic and foreign genetic resource users, including researchers of environment and ecology and present the overall structure, and flow of acquisition, access, and benefit sharing (ABS) for the use of foreign genetic resources to help them respond appropriately to the new landscape. The researchers' efforts and support at the national level are necessary at the same time to appropriately respond to the Nagoya Protocol. First, the researchers must understand the overall framework and the specific response in each stage under the Nagoya Protocol scheme. It is necessary to respond to the ABS procedure of the resource provider country from accessing genetic resources to sharing benefits resulting from it. In that regard, the Nagoya Protocol has imposed more restrictions on research activities and raised the burden outside of research. The current trend of recognizing the country's sovereign rights over genetic resources is likely to continue and widespread worldwide as resource-rich countries are expected to continue protecting their resources. Therefore, our study will help environmental ecology researchers understand ABS and conduct research under the Nagoya Protocol and legal obligations of resource provider countries step by step, from access to benefit sharing.

Investigation on the Awareness and Preference for Wood Culture to Promote the Value of Wood: I. Awareness of Wood and Cultural Experience (목재의 가치증진을 위한 목재문화에 대한 인식 및 선호도 조사: I. 목재와 문화체험에 대한 인식)

  • HAN, Yeonjung;LEE, Sang-Min
    • Journal of the Korean Wood Science and Technology
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    • v.49 no.6
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    • pp.616-642
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    • 2021
  • Improving public awareness of wood is essential for achieving the goal of establishing wood culture by expanding the use of wood. This study presents a basic examination of the strategy of revitalizing wood culture and a survey of its current status and requirements. The survey was divided into seven categories: awareness of wood culture; use characteristics of wood culture; preference and demand for wood culture; awareness of sub-fields of wood culture; awareness of the cultural resources of wood; trends of wood utilization; and wood-related living environment. Based on the survey results, the study analyzed four items: awareness of wood and cultural experience; awareness of the cultural resources of wood; wood-related living environment and trends of wood utilization; and preference and demand for wood culture. In this study, the public awareness of wood and cultural experiences, the first of four items, was analyzed using the survey results. Generally, wood and wood culture are viewed as materials and a cultural heritage, respectively. Moreover, wood is ecofriendly. However, no substantial difference was observed between the two perceptions. Forty-five percent of the respondents reported that using wood exerts a positive effect on the body and mind. However, such use also destroys forests. Additionally, the recognition of wood-related workers, such as engineers or skilled workers, was relatively low compared with educators, such as wood education experts. Moreover, less than 50% of the respondents answered that major projects related to wood culture are well-known, whereas 30% participated in wood education, such as woodworking experience, where the majority required hand tools. Furniture, wooden accessories, and wooden buildings were among the objects that individuals intended to make through the wood culture program. Approximately 23% of the respondents were aware about the wood culture experience center, while approximately 50% had visited it. The response rate to woodworking technology was 73%, where the highest response was found for wood education experts. To improve public awareness about wood, the importance of entertainment factors over educational factors should be considered in the experience of individuals. To provide opportunities to experience wood culture for more individuals, developing and actively promoting various contents, including entertainment elements, are necessary.

Development and assessment of pre-release discharge technology for response to flood on deteriorated reservoirs dealing with abnormal weather events (이상기후대비 노후저수지 홍수 대응을 위한 사전방류 기술개발 및 평가)

  • Moon, Soojin;Jeong, Changsam;Choi, Byounghan;Kim, Seungwook;Jang, Daewon
    • Journal of Korea Water Resources Association
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    • v.56 no.11
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    • pp.775-784
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    • 2023
  • With the increasing trend of extreme rainfall that exceeds the design frequency of man-made structures due to extreme weather, it is necessary to review the safety of agricultural reservoirs designed in the past. However, there are no local government-managed reservoirs (13,685) that can be discharged in an emergency, except for reservoirs over a certain size under the jurisdiction of the Korea Rural Affairs Corporation. In this case, it is important to quickly deploy a mobile siphon to the site for preliminary discharge, and this study evaluated the applicability of a mobile siphon with a diameter of 200 mm, a minimum water level difference of 6 m, 420 (m2/h), and 10,000 (m2/day), which can perform both preliminary and emergency discharge functions, to the Yugum Reservoir in Gyeongju City. The test bed, Yugum Reservoir, is a facility that was completed in 1945 and has been in use for about 78 years. According to the hydrological stability analysis, the lowest height of the current dam crest section is 27.15 (EL.m), which is 0.29m lower than the reviewed flood level of 27.44 (EL.m), indicating that there is a possibility of lunar flow through the embankment, and the headroom is insufficient by 1.72 m, so it was reviewed as not securing hydrological safety. The water level-volume curve was arbitrarily derived because it was difficult to clearly establish the water level-flow relationship curve of the reservoir since the water level-flow measurement was not carried out regularly, and based on the derived curve, the algorithm for operating small and medium-sized old reservoirs was developed to consider the pre-discharge time, the amount of spillway discharge, and to predict the reservoir lunar flow time according to the flood volume by frequency, thereby securing evacuation time in advance and reducing the risk of collapse. Based on one row of 200 mm diameter mobile siphons, the optimal pre-discharge time to secure evacuation time (about 1 hour) while maintaining 80% of the upper limit water level (about 30,000 m2) during a 30-year flood was analyzed to be 12 hours earlier. If the pre-discharge technology utilizing siphons for small and medium-sized old reservoirs and the algorithm for reservoir operation are implemented in advance in case of abnormal weather and the decision-making of managers is supported, it is possible to secure the safety of residents in the risk area of reservoir collapse, resolve the anxiety of residents through the establishment of a support system for evacuating residents, and reduce risk factors by providing risk avoidance measures in the event of a reservoir risk situation.

Problems and Improvement Measures of Private Consulting Firms Working on Rural Area Development (농촌지역개발 민간컨설팅회사의 실태와 개선방안)

  • Kim, Jung Tae
    • Journal of Agricultural Extension & Community Development
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    • v.21 no.2
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    • pp.1-28
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    • 2014
  • Private consulting firms that are currently participating in rural area development projects with a bottom-up approach are involved in nearly all areas of rural area development, and the policy environment that emphasizes the bottom-up approach will further expand their participation. Reviews of private consulting firms, which started out with high expectations in the beginning, are now becoming rather negative. Expertise is the key issue in the controversy over private consulting firms, and the analysis tends to limit the causes of the problems within firms. This study was conducted on the premise that the fixation on cause and structure results in policy issues in the promotion process. That is because the government authorities are responsible for managing and supervising the implementation of policies, not developing the policies. The current issues with consulting firms emerged because of the hasty implementation of private consulting through the government policy trend without sufficient consideration, as well as the policy environment that demanded short-term outcomes even though the purpose of bottom-up rural area development lies in the ideology of endogenous development focused on the changes in residents' perceptions. Research was conducted to determine how the problems of private consulting firms that emerged and were addressed in this context influenced the consulting market, using current data and based on the firms' business performance. In analyzing the types, firms were divided into three groups: top performers including market leaders (9), excellent performers (36), and average performers (34). An analysis of the correlation between the business performance of each type and managerial resources such as each firm's expertise revealed that there was only a correlation between human resources and regional development in excellent performers, and none was found with the other types. These results imply that external factors other than a firm's capabilities (e.g., expertise) play a significant role in the standards of selecting private consulting firms. Thus, government authorities must reflect on their error of hastily adopting private consulting firms without sufficient consideration and must urgently establish response measures.

Health Assessment for Glass Fibre Landfill at Gozan-dong, Inchon (인천시 고잔동에서 제기된 유리섬유에 의한 건강피해 역학 조사)

  • Cho, Soo-Hun;Ju, Yeong-Su;Kim, Kyung-Ryul;Lee, Kang-Kun;Hong, Kug-Sun;Eun, Hee-Chul;Song, Dong-Bin;Hong, Jae-Woong;Kwon, Ho-Jang;Ha, Mi-Na;Han, Sang-Hwan;Seong, Joo-Heon;Kang, Jong-Won
    • Journal of Preventive Medicine and Public Health
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    • v.30 no.1 s.56
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    • pp.77-101
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    • 1997
  • In September 1994, residents of Gozan-dong, Incheon City, made a petition to the government about their health problems which might be caused by previous glass fibre landfill nearby 'H' company. In february 1995, at regular academic meeting of occupational and environmental medicine, a research team of 'D' University presented that they had found glass fibres in groundwater of the area through their survey. They were suspicious of probable association between ingestion of groundwater contaminated with glass fibres and skin tumors among residents. A joint research team was formed and carried out the survey of environment concerning groundwater and its glass fibre existence, and health assessment of residents in the area and industrial workers of 'H' company during May to November, 1995. Analysis of groundwater flow system indicates that the flow lines from the glass fibre landfill pass through or terminate at the 6 houses around the landfill. This means that the groundwater of the 6 houses around the glass fibre landfill could be affected by some possible contaminants from the landfill, but the groundwater quality of the other houses was irrelevant to the landfill. The qualitative and qualitative analyses for glass fibres in 54 groundwater samples including those from the nearby 6 houses, were carried out using SEM equipped with EDS, resulting in no evidence for the presence of glass fibres in the waters. Major precipitates, formed in waters while boiling, were identified as calcium carbonates, in particulary, aragonites in needle form. The results of health assessments of 889 residents in Gozan-dong, participated in this study, showed statistically significant differences in past medical histories of skin tumor and respiratory disease between the exposed group (31 persons who inhabited in 6 houses around the landfill) and the control group, but no significant differences in past medical histories of other diseases, such as cancer mortality, current gastroscopic findings, current skin diseases and respiratory diseases, etc. Also, we could not prove any glass fibres in excised specimens of 9 skin tumors in both groups and there were no health problems possibly associated with glass fibres in employees of the 'H' company. After all, we could not authenticate the association, raised by prior investigators, between groundwater streams, assumedly contaminated with glass fibres or not, and specific disease morbidities or common disease/symptom prevalences. That is, we could not find any glass fibres in groundwater as the only exposure factor of this study hypothesis, and there were not enough certain evidences such as increasing disease prevalences, for examples, skin, respiratory and gastrointestinal diseases etc, possibly related to glass fibre exposure, in exposed group. As a matter of course, the conditions for confirming causal association, for example, strength of the association, consistency of the association, specificity of the association, temporality of the association and dose-response relationship etc, have not been satisfied. In conclusion, we were not able to certify the hypothesis that contamination of groundwater with glass fibres might cause any hazardous health effects in residents who used it for drinking.

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