• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.74-74
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• 2011

본 연구에서는 중앙경간 54m, 교폭 4m의 사장교형식의 보도교로 측경간은 계단으로 이루어진 1경간 케이블교량을 대상으로 보행하중에 의한 수직진동을 제어하기 위해 제진장치(TMD)를 적용하기로 하고 실물 TMD의 설계 및 제작 그리고 설치 및 제어성능실험을 수행하였다. 우선 사장교형식의 교량. 그리고 1경간 교량이라는 점에서 상대적으로 감쇠율이 낮을 것으로 예측되었고 또한 54m의 경간장이 보행자가 가진 주파수에 근접한 고유진동수를 나타낼 것으로 사료되어 Eurocode 2 part 2(EC5-2)의 규준에 따라 1인 및 다수 보행하중에 의한 보도교의 발생가속도를 산출하였다. 이 경우 최대가속도는 다수의 보행자가 연속적으로 진행할 때 발생하였으며, 수직방향의 가속도가 사용성기준을 초과하는 것으로 나타났다. 또한 구조해석프로그램에 의한 고유치 해석결과, 보행하중의 주파수대역내에 진동모드가 존재하는 것으로 나타났다. 따라서 본 교량의 설계단계에 있어서 보행진동을 제어하기 위하여 유지관리가 용이한 수동형의 동조질량감쇠장치(Tuned Mass Damper)를 적용하기로 하였으며 TMD의 설계에서는 TMD의 제어목표를 만족시킬 수 있는 TMD의 가동질량(moving mass)을 우선적으로 결정하였고, 이로부터 Den Hartog의 제안식에 따라 TMD의 고유진동수비, 유효감쇠비를 산정하였다. 산정된 변수들을 이용하여 설계된 TMD는 현장설치 및 튜닝의 편의성을 고려하여 수평 외팔보형식으로 설계, 제작되었으며 제작된 TMD의 경우 회전축에 대해 질량, 스프링, 댐퍼의 중심거리를 조정함으로써 TMD의 진동수, 강성, 감쇠력을 상대적으로 매우 용이하게 조절할 수 있으며, 조정범위 또한 광범위하여 일반 TMD에 비해 현장설치시 대상구조물에 동조시키기가 용이하며, 작동시 마찰감쇠가 거의 없다는 장점이 있다. 현장설치전에 제작된 TMD를 대상으로 자유진동 시험을 통하여 질량의 중심거리, 스프링 크기 그리고 댐퍼의 설치유무를 각각 변화시키며 TMD의 자유진동 데이터를 취득하였다. 각각의 시험에서 얻어진 데이터로부터 스펙트럼해석을 통하여 고유진동수를 구하였고, 자유진동 파형으로 부터 감쇠비를 구하였다. TMD는 일반적으로 제어모드의 변형형상이 가장 큰 곳에 설치되었을 때 최대의 제진효과를 발휘할 수 있다. 그러나 현장여건상 설치가 불가능하거나 미관을 해치는 경우에는 가능한 범위 내에서 TMD 제어효율이 가장 크게 발휘할 수 있는 곳을 선택하여야 한다. 본 보도교의 경우, 중앙경간 중심부에서 가장 큰 모드변형형상을 나타내지만, 보도교의 상판 연결부 등에 따른 TMD 시공문제로 인하여 TMD 설치위치는 교량 중앙에서 양 방향으로 1.25m 떨어진 곳에 대칭으로 총 2기를 설치하기로 하였다. 일반적으로 TMD의 모든 설계변수는 구조물의 설계단계에서 수행된 구조해석결과에 근거하여 설정하므로 완공된 구조물, 즉 실제보도교의 동적특성을 계측하여 정확하게 진동수를 튜닝하여야 한다. 구조해석에 의한 보도교의 수직방향(TMD 작동방향) 고유진동수는 1.5225 Hz이며, 감쇠비는 규준에 의하여 0.6 %로 가정하였다. 그러나 이 값들은 구조해석모델 및 재료적 특성과 시공상의 오차에 의하여 실제와 다를 수 있으므로 현장계측에 의한 확인이 요구된다. 또한 TMD의 제진효율이 설계시의 목표대로 확보되었는지도 확인해야 하므로 현장튜닝 및 성능시험을 실시하였다. 보도교의 가진은 사전에 실시한 상시 미진동계측결과를 토대로 2Hz를 목표로 하여 인력가진실험을 수행하였고, 탁월진동 주파수는 1.9896Hz로 나타나 구조해석결과와 오차가 있음을 알 수 있다. 가진실험결과를 토대로 TMD의 진동수를 최적진동수비로 튜닝하고 인력가진 실험을 다시 실시하여 TMD의 진동제어성능을 검토하였다. TMD 튜닝 전, 후의 보도교 감쇠비를 비교한 결과, TMD를 설치함으로써 약 4.218%의 감쇠비 증가가 있음을 알 수 있다.

• Korean Journal of Childcare and Education
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• v.10 no.5
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• pp.5-23
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• 2014

The purpose of this study was to identify factors affecting extra expenses incurred by extracurricular activities, prompted by the problem that the financial burden on households for their children's education and child-care is not showing enough signs of being mitigated, despite increased child-care subsidies from the government. Data for this study was obtained from the 4th Panel Study on Korean Children of Korea Institute of Child Care and Education. The analysis of the study shows that 68.5% of the surveyed children were participating in extracurricular activities and the average number of extracurricular activities they took part in was 2.9. The average extracurricular expenditure was 50.000 won. However, based on the findings of the survey, it was statistically significant to find that the number of extracurricular activities the children participated in and the expenditure the households spent on them varied by area. Variables were inserted in a gradual manner in identifying factors influencing households' expenditure on children's extracurricular activities. The results showed that amongst the variables used, the education level of the mother, the employment status of the mother, the type of the child-care support institution, and the household's place of residence featured prominently, with the place-of-residence factor accounting for most of the reason why a household spent the amount it did. The outcome of the study bears four policy implications: First, there is a need for a specific evaluation of the contents and costs of extracurricular activities and supervision and management of such activities. Second, it is necessary for the central government to provide a specific criteria of necessary expense. Third, throughout the child support agency, the courses and costs of special activities should be monitored regularly. Fourth, there should be extracurricular activity support for underprivileged children.

• Culinary science and hospitality research
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• v.21 no.2
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• pp.60-74
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• 2015

This study seeks to determine causal relationships between hotel internal marketing practices and job satisfaction, and ultimately on organizational commitment, to contribute information enabling hotel management to better understand employees working in hotel culinary departments. SPSS 18.0 and AMOS 18.0 were employed for the statistical analysis (e.g. frequency statistics, exploratory factor analysis, confirmatory factor analysis, reliability analysis, and structure equation model). Results revealed that the formulated model showed proper model fit (${\chi}^2=227.154$(df=179), p-value=0.009, CMIN/DF=1.269, RMR=0.013, GFI=0.931, AGFI=0.911, NFI=0.906, CFI=0.978, RMSEA=0.031), and confirmed construct reliability and convergent validity. Three factors (benefit package, educational training, work autonomy) were extracted based on the results of the factor analyses. Specifically, benefit package and work autonomy exhibited an effect on job satisfaction with benefit package asthe most significant factor (t-value 3.311, p<0.001), partially supporting the first hypothesis of this study. In addition, job satisfaction has found to have a positive influence in organizational commitment, confirming the second hypothesis of this study.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.2
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• pp.187-200
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• 2014

Industry Cooperation is not the choice of national development but the inevitable component in the world. Industry cooperation results of the reconstruction of the country is an important place as an essential element of the economic development of the national policy in the major economies. Despite several changes in the international economic environment, United States, Canada, Finland, Sweden, Israel settled and maintaining the sustainable development of the countries which successfully established Industry-University Cooperation or Industry-Acaemy Cooperation system in history. In this study, delivered to the realistic ways of Industry cooperation through comparison study on domestic and international cooperation programs. The new activation programs of industry academic cooperation are delivered, that is, The bonus payments system of technology development patent and free technology transfer for joint development, bonus points system and evaluation indicators for joint capacity building program which participate student, industry and academic sector, step-by-step training. system for total employment and entrepreneurship at the same time strengthening management training programs and education opportunity gives to the benefits for the community members. Finally, Intellectual property expert matching program which develops basis of technology trader and expert maps in the smallest unit by administrative area. practice the internet information search services in national wide network for this matching program and government office dedicated to staffing for technology transfer.

• Journal of Korean Home Economics Education Association
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• v.27 no.3
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• pp.99-119
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• 2015

The purpose of this study is to examine the educational contents of home economics textbooks that solely focus on forming adolescent empowerment. For this, an in-depth content analysis was conducted on the home economics textbooks in Korea and the U.S. The main results of this study are summarized as follows: First, the 23 content elements, which are designed to build adolescent empowerment, were ascertained: nine intrapersonal empowerment elements such as the self-identity, nine interpersonal empowerment elements such as the communication, and five social empowerment elements such as the leadership. Second, based on the content elements selected from above, the textbooks in Korea were observed to deal with 58% of the 23 content elements, while those in the U.S. discussed 90% of the 23 content elements. Korean textbooks primarily focused on helping students understand major concepts, whereas the U.S. textbooks focused primarily on helping students make connections between major concepts and their life. Lastly, both countries put the least amount of weight on social empowerment content elements(Korea: 37%, U.S.: 70%).

• Journal of Yeungnam Medical Science
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• v.24 no.2
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• pp.137-147
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• 2007

Background : Interpretative reporting is an important aspect of laboratory medicine. The large menu of laboratory tests available today makes it increasingly difficult for the non-specialist to order and interpret all laboratory tests. The aim of this study was to determine the usefulness of an expert system to interpret laboratory tests and help physicians order the appropriate tests. Materials and Methods : In order to interpret laboratory tests, a rules-based expert system was developed. In this module, if-then rules were used to interpret the given test result patterns (e.g. urinalysis, anemia, hepatitis B virus, hypercholesterolemia, glucose, syphilis, and tumor markers) and select matching text elements. The system was used to evaluate 535 subjects who visited a health-check program. Results : The overall abnormal rate was 50.5% in the expert system; 34% for cholesterol, 9.9% for urinalysis, 8.0% for anemia, 7.7% for thyroid function tests, 4.5% for tumor marker study, 4.7% for hepatitis virus antigen, 4.3% for serum glucose, and 1.1% for syphilis. Conclusion : These results indicate that the application of the expert system for the interpretation of laboratory tests may provide a useful method for the interpretation of reports. However more rules are needed for the application to in-patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.170-177
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• 2017

The price of land in Jeju is reaching a new high every day and this phenomenon not only causes real difficulties for the purchase of real estate by local residents, but also results in psychological deprivation. Therefore, this study analyzes the factors causing the increase of the land price in Jeju, in order to examine the measures required to stabilize the land price which is continuously rising. As a result of this study, we developed a land price prediction model including seven variables, including the 'inflation rate', 'interest rate', and 'population'. According to the model, land prices in Jeju are expected to rise steadily, and it is predicted that in 2020 the price will increase to 170% of that in 2015 and will triple by 2025. Based on the results of this study, this study suggested policy alternatives, such as 'Establishing a tourism policy for managing the number of tourists' and 'increasing the approval standards for development activities'. The two policies proposed in this study can be implemented as a regional initiative, which may be less effective than the changes in the national system, but it is meaningful that the efforts to stabilize the land price will continue at the regional level.

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.45-52
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• 2008

The objectives of this study are to explain a supply plan of domestic softwood log by long-term prospect of MDF production to stably promote industry of MDF. For it, we developed the long supply function as Ordinary Least Squares Method. Between 2005 and 2050, it was estimated that quantity of domestic production of MDF increased from 1,653 thousand $m^3$ to 2,041 thousand $m^3$. In 2050, quantities of domestic softwood log used by raw materials to product MDF of 2,041 thousand $m^3$ were estimated to be used about 1,355 thousand $m^3$. Exampling Pinus rigida used presently by raw materials to product MDF, cutting area of it is estimated to be 10,828 ha per year. And larch is cutted about 9,160 ha per year. This study estimated annual softwood log cutting amount and total afforestation area at 2050 year by 3 scenarios which are 35%, 45% and 55% about use of domestic softwood log for MDF production. If we do a criterion of cutting area, we advantage to plant larch. But the species of trees are use and growth property. We think that the afforestation policy must be performed on the base of those to supply raw materials of MDF. Although government plans hardwood afforestation policy after cutting Pinus rigida, it needs to support and manage certainly afforestation area of softwoods to need to supply raw materials of MDF to stably promote industry of MDF.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.6
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• pp.29-42
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• 2013

The purpose of this study was to derive selection attribute of fishing experience villages, and to analyze the importance and performance on targeting experts and experienced tourists. Consequently, it could suggest implications for the guideline and the evaluation criteria of making fishing experience villages for the revitalization of eco experience tourism. Therefore, in this study, literature investigation and IPA analysis were used by Microsoft Office Excel 2010, SPSS 20.0. As a result, the 'variety of local foods and specialties' was the most urgent attribute to require intensive management strategy. And it is recommended to improvement about 'attributes related residents' because it were insensitived on the recognition by users. Satisfaction of 'appropriateness of coast' was the lowest, but the efficiency was quite high. Finally, not only 'the area of control' but also 'the area of influence' should be reviewed as an important aspects on developing the fishing experience village. The significance of this study is to derive selection attributes of making fishing experience villages for revitalization of eco experience tourism, and to suggest strategy directions based on IPA analysis result by experts and experienced tourists. But in this study, the site was limited to Gyeonggi-do, so it is recommended to expand further.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.6
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• pp.348-355
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• 2017

Human activities have resulted in soil pollution problems to us. Human and ecological risk assessment have been suggested as an efficient environmental management strategy for protecting human and ecosystems from soil pollution. However, Korean environmental policy is currently focused on human protection, and fundamental researches for ecology protection are required for institutional frameworks. In this study, we developed a schematic frame of Korean soil ecological risk assessment, and suggested the basic information for its application. This study suggested a soil ecological risk assessment scheme consisting of 4 steps for derivation of Predicted-No-Effect-Concentration (PNEC): 1) ecotoxicity data collection and reliability determination, 2) data standardization, 3) evaluation of data completeness for PNEC calculation, and 4) determination of ecological-risk. The reliability determination of ecotoxicity data was performed using Reliability Index (RI), and the classification of domestic species, acute/chronic, toxicity endpoint, and soil properties was used for data cataloging. The PNEC calculation methodology was determined as low-reliability, middle-reliability, and high-reliability according to their quantitative and qualitative levels of ecotoxicity data. This study would be the introductory plan research for establishment of Korean soil ecological risk assessment, and it can be a fundamental framework to further develop guidelines of Korean environmental regulation.