• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.431-431
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• 2016

J 호소는 1942년도에 충청남도 아산시 선장면에 설치된 농업용 저수지로서, 현재 COD, TN, TP 모두 등급외의 수질상태를 보이고 있다. J 호소 상류 유역은 축산농가가 다수 위치하고 있으며, 설치된 지 70년이 지난 노후화된 저수지로 고농도의 오염물질 유입뿐만 아니라 호소 바닥의 오염 퇴적물에 의한 내부 부하가 중요한 수질오염원이 되고 있다. 호소의 수질은 현재 COD 10.6~16.5 mg/L, Chl-a $75mg/m^3$ 이상으로 수질오염도가 매우 높으며, 특히 늦봄에서 초가을까지 외기온도 상승 및 저수율 저하와 함께 부영양화 증가, 녹조 대발생 등으로 호 내 물고기 대량 폐사 및 악취발생 등으로 민원이 다수 발생하고 있다. 이러한 현상의 직접적인 원인은 수중의 DO 농도 결핍이며, 따라서 수중의 DO 농도를 일정수준 이상으로 유지시켜 주는 것은 호소 수질관리를 위해 매우 필요하다고 판단된다. 본 연구에서는 공기 중의 산소를 호소 수체에 포기시켜 주는 마이크로버블 발생장치를 J 저수지에 설치하여 수체의 DO 농도 변화 등을 분석하였고, 본 연구결과는 농업용 호소의 수질개선을 위한 기술개발 및 계획수립의 기초자료로 활용하고자 하였다. 마이크로버블 포기장치는 수심이 약 4m 되는 저수지 제방 근처에 100m 간격으로 총 3지점에 설치하였다. 버블 발생기는 기액 2상류 선회형 마이크로 버블 발생장치로 3지점에 각 1set(1set에 3기로 구성)씩 구성하여 저수지 바닥 층에서 상부로 1m 떨어진 지점에 고정식으로 설치하였다. 총 공기흡입량은 380 LPM이며, 사용동력은 12.2kW를 사용하였다. 마이크로 버블 포기장치 설치 후 호 내 DO 농도 변화를 평가하기 위하여 호소 전체에 18개 지점을 선정하여 수심 50cm 간격으로 DO 농도를 측정하였다. 가동 전에는 DO 평균농도가 표층에서는 약 7.7mg/L로 나타났고, 수심에 따라 거의 수직적으로 감소하여 바닥층에서는 약 0.2mg/L로 거의 무산소 상태를 보이고 있었다. 마이크로 버블 가동 2주 후에는 수심 3m까지의 모든 수층에서 DO 농도가 약 6.0mg/L 이상을 보였고, 바닥층에서는 DO 약 3.4mg/의 농도를 나타내었다. 가동 3주 후에도 2주 후와 비슷한 수치를 보이고 있었으나 가동 4주가 지나면서부터는 호소 바닥층(수심 3.5m)에서도 DO 농도가 7.0mg/L 이상의 높은 농도를 유지하는 것으로 조사되었다. 호소 저층에서 호기성 상태의 지속적 유지는 퇴적 오염물질이 수층으로 용출되는 것을 예방할 수 있으므로 마이크로버블을 잘 활용하면 호소의 악취제거 및 수질개선에 많은 도움이 될 것으로 판단된다.

• 한국벤처창업학회:학술대회논문집
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• 2018.11a
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• pp.201-213
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• 2018

This paper empirically analyzed whether or not professional college students' Protean career attitudes affect entrepreneurial intention through employability and entrepreneurship, and whether or not they have practical training experiences can make a difference in such influence. For this reason, a questionnaire survey was conducted on about 240 students at specialized universities in Seoul and the Gyeonggi province for one month beginning on June 1, 2018. Of the 220 collected questionnaires, 214 parts in total were selected for final analysis, except for the 6 parts of the answer sheet which were not sure if there was a missing value or not. The main findings are as follows. First, it has been confirmed that the professional career attitude of Protean has influenced employability and entrepreneurial intention, but has not directly influenced entrepreneurial intention. Secondly, it has been confirmed that the employability and entrepreneurship have have a positive influence on the entrepreneurial intention. Thirdly, it has been confirmed that employability and entrepreneurship play a role as a fully mediated role in the relationship between the attitude of the Protean career and the entrepreneurial intention. Fourthly, considering the characteristics of the vocational college, there is no difference in the influence of employability and entrepreneurship on the entrepreneurial intentions, but the influence of the protean career attitude on employability and entrepreneuriship was different depending on whether or not they had the practical training experiences. This study is to analyze the relationship between the protean career attitude and the entrepreneurial intention in the aspect of employment and entrepreneurial activation of young people.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.245-245
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• 2022

최근 국내 기후변화에 따른 국지성 집중호우로 인한 시간당 강우량의 증가로 도로부 유출량의 증가와 배수관거에서의 내수배제 불량에 따른 도심지 내수침수 피해가 증가함에 따라 이를 해결하기 위한 우수유출저감시설이 설치되고 있다. 그러나 대단위의 지하 저류시설의 지속적인 설치는 과밀화된 도심지에서 설치 지하공간의 구조적인 한계 및 적정 설치 위치의 미확보 등의 다양한 문제가 발생하여 저류시설의 침수저감 효과에 대한 추가적이고 새로운 저류시설에 대한 연구가 필요한 실정이다. 이에 내수 침수 저감 및 배수 능력 향상을 위한 도로 배수시설과 연계된 도로 측구부 저류시스템 구축이 필요하다. 이를 위해 역류 방지 및 노면수 저류 빗물받이에 적용되는 부력식 역류차단장치를 개발하였으며, 역류차단장치의 최적 형상 개발을 위해서 기존 빗물받이 연결관과의 통수능 비교 및 분석이 필요한 실정이다. 따라서 본 연구에서는 기존 빗물받이 연결관 및 연결관 내에 역류차단장치가 적용된 역류차단 빗물받이의 흐름분석을 위해 Fluent 모형을 이용하여 3차원 수치모의를 수행하였다. 수치모의 구성으로는 전체 형상을 40×50cm의 빗물받이 유입부와 50×50cm의 빗물받이로 결정하고 격자는 빗물받이 내부의 복잡한 3차원 흐름을 모의하기 위해 1.2~2mm 크기로 생성하였다. 다상유동 해석을 위해 VOF(Volume of Fluid)방법을 적용하였고, 수치해석 방법으로는 비정상류, 난류 모형으로는 SST k-𝜔모형을 적용하였다. 해석조건으로는 김정수(2021) 등이 제시한 4차선 기준 설계빈도별(5~30년) 빗물받이 유입유량을 산정하여 빗물받이 유입조건으로 선정하였으며, 빗물받이와 연결관에서의 통수능력 분석 조건으로는 빗물받이에 기존 연결관이 부착된 조건과 연결관 내에 역류차단장치가 설치되어 역류차단장치가 개방된 조건에서의 통수능을 비교하였으며, 역류상황을 가정한 연결관에서의 통수능을 비교하기 위하여 역류차단장치의 개폐정도를 15도(통수단면 33%감소) 닫힌 상태 및 30도(통수단면 67% 감소) 닫힌 상태 조건을 대상으로 빗물받이와 연결관에서의 흐름을 모의하였다. 수치모의 결과 역류차단장치의 계폐조건에 상관없이 5년 빈도유입량 조건에서는 완전 배수가 되었으며, 개폐조건 15도에서는 10년 빈도의 유입량에서는 완전 배수가 되었으나 20년 빈도 이상의 유입량 조건에서 빗물받이 유입부로의 역류가 발생하였으며, 개폐조건 30도에서는 5년 빈도 이상 유입량 조건에서 빗물받이 유입부로 역류가 발생하는 것으로 나타났다. 특히, 30년 빈도 이상의 유입량부터는 빗물받이 연결관 내에 역류차단장치 개페조건과 관계없이 빗물받이 유입부로의 역류로 인한 도로 침수가 발생하기 때문에 유휴공간인 도로 측구부를 저류공간으로 활용할 수 있는 도로 측구부 저류시스템의 구축은 필수적이라고 판단되며, 유량 조건에 따른 빗물받이 내부 와 흐름과 유출부에서의 유속 변화 특성을 확인하였다. 그러므로 측구 저류조 개발 형상과 연결한 3차원 흐름의 구현 및 분석에 Fluent 모형의 적용이 가능하다고 판단된다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.99-99
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• 2020

참당귀(Angelica gigas Nakai)는 중국의 동북부지역, 일본 및 한반도 전역에 자생하고 있으며, 예로부터 보혈, 활혈지통, 윤장등의 효능으로 심신혈허, 월경불순, 통경경폐 등의 병증에 주로 사용되었고, 8월부터 뿌리가 급격히 비대하여 10월 말에서 11월 초에 수확을 한다. 본 연구는 참당귀의 주산지인 봉화, 평창을 비롯한 영양, 인제 등 4지역을 선정하여 미세기상장비를 설치 및 토양의 이화학성 분석을 통해 지역별 생육환경을 측정하였고, 또한 참당귀의 생육특성을 조사하였다. 그 결과 5월에서 10월까지 평균 대기온도와 일사량은 인제지역에서 다른지역에 비해 비교적 높은 경향을 나타냈다. 또한 토양온도는 5월에서 8월까지는 영양지역이, 9월과 10월은 봉화지역이 다른지역에 비해 비교적 높은 것으로 조사되었다. 지역별 토양 성분의 이화학적 특성은 봉화지역이 유기물(5.17%), 전질소(0.19%), 유효인산(2187.76mg/kg), 칼륨(1.53cmol⁺/kg)의 함량이 다른 지역에 비해 높은 경향으로 확인되었고, 인제지역이 칼슘(12.63 cmol⁺/kg), 마그네슘(3.7cmol⁺/kg)등 미량원소의 함량이 높은 것으로 분석되었다. pH는 지역별 차이가 확인되지 않았으며, 영양지역의 토성이 사질식양토로 배수성의 차이는 확인되었다. 이에 따른 참당귀의 생육특성은 초장과 줄기직경은 영양지역에서 각각 70.95cm와 35.72mm로 가장 높게 측정되었으며, 잎 길이및 너비는 평창지역에서 각각 42.84cm, 52.39cm로 가장 높게 측정되었다. 뿌리직경은 영양에서 50.49mm, 뿌리길이는 봉화에서 38.05cm, 생중량은 평창에서 328.23g으로 다른지역에 비해 높은 경향을 나타냈다. 상기 결과를 바탕 재배환경과 생장량간의 상관관계를 분석하였다. 재배환경 중 대기 및 토양온도, 대기 습도는 실험이 수행되어진 전 지역에서 이상고온이나 저온과 같은 특이점 없이 비슷한 양상으로 측정되었고, 이에 따라 참당귀생장에 대해 유의한 상관관계가 분석되지 않았다. 토양습도는 지상부(초장, 줄기직경, 잎길이, 잎너비)의 생육과 음의 상관관계에 있다고 사료되나 유의성이 검증되지 않았다.

• Korean Journal of Environment and Ecology
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• v.33 no.3
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• pp.280-291
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• 2019

A. antiquum, first observed in Jeju Samdo Island in 1949, was designated as the Natural Monument No. 18 in December 1962 in recognition of its academic value. In Korea, it grows in nature only in Samdo in Jeju Island. Although its natural habitat was greatly damaged and almost destroyed due to firewood, stealing, etc. After the emancipation, it has been maintained by the transplantation and restoration. The site observed by this study has been managed as a restricted area since 2011. Since it has been about 20 years since the restoration of the native site in the 2000s, it is necessary to check the official management history records, such as the origin of transplantation and restoration to monitor the changes in the growth status and to control the habitat. As the results of this study, we have secured the records of cultural property management history, such as the identification of native species and the transplantation and restoration records. We also examined the change of the growth and development of A. antiquum 20 years after the restoration. There are no official records of the individuals transplanted to the restored natural habitat of A. antiquum in the 1970s and 1980s, and there was a controversy about the nativeness of those individuals that were restored and transplanted in 1974 since they were Japanese individuals. The studies of identifying native as the results of this study, we have secured the records of cultural property management history, such as the identification of native species and the transplantation and restoration records. We also examined the change of the growth and development of A. antiquum 20 years after the restoration. There are two sites in natural habitat in Samdo Island. A total of 65 individuals grow in three layers on three stone walls in a site while 29 individuals grow in two columns in the other site. A. antiquum grows in an evergreen broad-leaved forest dominated by Neolitsea sericea, and we did not find any other individuals of naturally growing A. antiquum outside the investigated site. This study checked the distribution of A. antiquum seedlings observed initially after the restoration. There were more than 300 seedling individuals, and we selected three densely populated sites for monitoring. There were 23 A. antiquum seedlings with 4 - 17 leaves per individual and the leaf length of 0.5 - 20 cm in monitoring site 1. There were 88 individuals with 5 - 6 leaves per individual and the leaf length of 1.3 - 10.4 cm in monitoring site 2 while there were 22 individuals with 5 - 9 leaves per individual and the leaf length of 4.5 - 12.1 cm in monitoring site 3. Although the natural habitat of A. antiquum was designated as a restricted public area in 2011, there is a high possibility that the habitat can be damaged because some activities, such as fishing and scuba diving are allowed. Therefore, it is necessary to enforce the law strictly, to provide sufficient education for the preservation of natural treasures, and to present accurate information about cultural assets.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.1
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• pp.142-151
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• 2020

This study is designed to deduce an implication for an effective implementation of the Special Act for Conservation, Management and Utilization of World Heritage in Korea which was legislated in February, 2020. To draw an implication, which is regarded as highly valuable for preparing for the implementation of the act, several case studies were performed focusing on four World Natural Heritage sites in Japan, and the result is as follows. First, it is enormously crucial for the central administration agencies and the local government to have a system through which they communicate one another regularly. All the target areas in Japan consist of three national parks and a prefectural park with natural monuments, and the national forest covers a tremendously large proportion of the areas. The Japanese central agencies including Ministry of the Environment, Forestry Agency and Agency for Cultural Affairs have communication with the local government through a system named Regional Liaison Committee in order to manage the sites effectively. Also, in the case of Japan, de facto administrating agencies involving non-profit organizations and the tourism association also participate in the regular conferences to communicate. Second, a specific committee consisting of academic advisers is strongly needed. In the case of Japan, Scientific Committee provides academic grounds for the management plan established by the members of Regional Liaison Committee, and an active system which allows the members to organize consultative committees and subcommittees has been established. Scientific Committee plays an important role in preventing the local government, which tends to manage the world natural heritage in more economically profitable ways, from damaging the environment of the site. The establishment of this type of committee is thought to be extremely desirable because the World Natural Heritage requires comprehensive and sustainable management plans on the ecosystem. Third, establishment of comprehensive management plan based on continuous monitoring on the environment and detailed action plan is exceedingly needed. To sum up, it is vital to establish a management plan considering environmental aspect, and detailed guidelines, which help execute the plan both properly and effectively, are required for systematic and sustainable management.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.260-279
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• 2010

The analysis on bibliography and field investigation of Callipogon relictus Semenov, 1898 (Korean natural monument number 218) shows that the size varies from country to country, and Korean specimens, for which male is 85~120mm and female is 65~85mm, are found to be the largest. The average diameter and length of egg are 2.60mm and 6.72mm respectively. The larva has milky color and is about 100~150mm in length. The pupa is nearly 70~110mm. An adult generally appears from June to September in Korea in the broadleaf forest of lowland, whereas it appears from June to July in China. It is known that the pupa largely feed on the old tree trunk of Carpinus laxiflora (Siebold & Zucc.) blume in Korea, but no such data have been reported in China and Russia, showing differences in host plants. While the larva period is not exactly known in Korea, it is reported to be two years in China. It appears that the species inhabits in very limited regions of approximately between geographical latitude $37.5^{\circ}{\sim}47.8^{\circ}$ and longitude $126^{\circ}{\sim}140^{\circ}$ including Korea, China and Russia. To conserve the long-horned beetle in Korea, this research drew out following some conclusions through analyzing the references and field survey data. First, it need to perform precise survey on the natural environment of occurring and collected area or place including host plant kinds, temperate, humidity, latitude, longitude etc. Second, habitat region must be designated as a restricted development area, and it need to exclude or reduce the damage factors to prosper reproduction of the species. Third, it is necessary to keep loosing cautiously artificial breeding individuals in the reported sites, not disturbing scope of natural populations. Fourth, it needs to educate or publicize many people importance and value of this species through many methods.

• Korean Journal of Construction Engineering and Management
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• v.15 no.5
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• pp.103-114
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• 2014

Data envelopment analysis (DEA) measures the relative efficiency of decision making units (DMUs) with multiple performance factors that are grouped into outputs and inputs. DEA has proven to be superior to simple aggregation of performance measures, and is also useful for evaluating the performance of construction companies for comparison with competitor performance. The purpose of this study was to survey literatures on the application of DEA methodology and to propose a methodological scheme to measure the performance of construction organizations. Articles on previous studies were surveyed and examined as part of a comprehensive review. The survey revealed that the application of DEA in the construction industry was li mited. Further, the survey indicated that there is a need for the development of a methodological framework on the special goals and subjects of performance measurement, methods of data structure and collection, selection of appropriate DEA models, analysis of results, and post-test. Based on the survey, this study identified and discussed the types of major issues and topics for future studies from a methodological perspective, which could be helpful to researchers interested in using DEA to study performance issues in construction organizations.

• Journal of The Korean Association For Science Education
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• v.40 no.5
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• pp.451-462
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• 2020

According to the online learning environment, learning activities using mobile technology have emerged as a major concern. The features of mobile technology show potential supporting the emergence of learners' agencies in science education. In this study, 22 research literature on mobile activities in science teaching and learning published in Korea from 2011 to April 2020 were selected. First, the framework of Suarez et al. (2018) was revised and the types of mobile activities were categorized and investigated. Second, the emergence of agencies was examined in the context of science teaching and learning. And also, the relevance of mobile activity types ('Access to content', 'Data collection', 'Peer-to-peer communication', 'Contextual support') to support learners' agency dimension ('goals', 'content', 'action', 'strategy', 'reflection', 'monitoring') was analyzed. The first analysis show that science teaching and learning through mobile activities are changing from traditional to student-centered. Through these activities, students become more involved in learning and get the opportunity to become agents of learning. As a result of the second analysis, it has been confirmed that the emergence of learners' agencies has been supported and strengthened through mobile activities. Whereas, it needs to look upon the relationship between learners' agency and mobile activities in the overall context of science class. This consideration led to implications for the use of mobile technology in future science education and the transition to student-centered education.

• The Journal of Korean Academy of Sensory Integration
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• v.18 no.1
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• pp.56-72
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• 2020

Objective : The purpose is to analyze the effects of parent training interventions in reducing the symptoms of Attention Deficit Hyperactivity Disorder (ADHD) and to provide a basis for the effects. Methods : We collected literature published in international academic journals from 2009 to 2019 through ProQuest and Scopus databases. The search key terms were (ADHD OR Attention Deficit Hyperactivity Disorder) AND (Parent OR Mother OR Father) AND (Training OR Program OR Therapy OR Intervention) AND (Randomized OR Randomised OR Randomly). The PEDro scale was used to evaluate the quality of the studies, and a meta-analysis was conducted through Comprehensive Meta-Analysis 3.0. Results : Of 628 studies that we reviewed, 20 were eligible for inclusion. of parental training interventions for children with ADHD appeared close to a medium effect size while parent-child interventions (0.639) appeared to have a medium to large effect size. Oppositional defiant behavior and conduct disorder (0.737) in children and children's emotions (0.679) appeared close to a large effect size. ADHD symptoms hyperactivity and impulsivity (0.590) and child behavior (0.521) appeared to be over a medium effect size. We chose a random-effects model since heterogeneity tests showed significant results. Conclusion : We were able to confirm the effects of parent training interventions on the symptoms of children with ADHD. This will be used as evidence to provide a clinical basis for occupational therapists. More research related to parental training interventions should be carried out to ensure better reporting in the future.