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A New Model for Forecasting Inundation Damage within Watersheds - An Artificial Neural Network Approach (인공신경망을 이용한 유역 내 침수피해 예측모형의 개발)

  • Chung, Kyung-Jin;Chen, Huaiqun;Kim, Albert S.
    • Journal of the Korean Society of Hazard Mitigation
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    • v.5 no.2 s.17
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    • pp.9-16
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    • 2005
  • This paper presents the use of an Artificial Neural Network (ANN) as a viable means of forecasting Inundation Damage Area (IDA) in many watersheds. In order to develop the forecasting model with various environmental factors, we selected 108 watershed areas in South Korea and collected 49 damage data sets from 1990 to 2000, of which each set is composed of 27 parameters including the IDA, rainfall amount, and land use. After successful training processes of the ANN, a good agreement (R=0.92) is obtained (under present conditions) between the measured values of the IDA and those predicted by the developed ANN using the remaining 26 data sets as input parameters. The results indicate that the inundation damage is affected by not only meteorological information such as the rainfall amount, but also various environmental characteristics of the watersheds. So, the ANN proves its present ability to predict the IDA caused by an event of complex factors in a specific watershed area using accumulated temporal-spatial information, and it also shows a potential capability to handle complex non-linear dynamic phenomena of environmental changes. In this light, the ANN can be further harnessed to estimate the importance of certain input parameters to an output (e.g., the IDA in this study), quantify the significance of parameters involved in pre-existing models, and contribute to the presumption, selection, and calibration of input parameters of conventional models.

Issues in Applying CV Methods to the Preliminary Feasibility Test (예비타당성조사 적용 CVM의 분석체계와 개선과제)

  • Eom, Young Sook;Kwon, Oh-Sang;Shin, Youngchul
    • Environmental and Resource Economics Review
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    • v.20 no.3
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    • pp.595-628
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    • 2011
  • This study investigates the issues and suggests reform measures in applying CV methods to the Korea Development Institute's (KDI's) Preliminary Feasibility Test (PFT) of public projects. Most public projects on culture, science and environment evaluated under the PFT system belong to the category of "nonstandard" projects whose outputs are non-marketed, and CV is currently the main tool used for their benefit estimation. A careful discussion and investigation is recommended for the selection of target population, payment vehicle, and number of payment times. Operating expert reviews, focus group interviews, and pre-tests is highly recommended to reduce the potential bias involved in the CV studies. A single or double bounded dichotomous choice format is the most popular design of questionnaire, but we identify several undissolved issues in designing and implementing the format. Some other forms of inducing WTPs may still deserve our consideration. Various specifications of the WTP function need to be tried and tested based on their stability, in particular. Employing a nonparametric approach is also recommended. Treatments of 0 or negative WTPs and protest bids are shown to be the most serious issues that affect the estimation results significantly. We review diverse measures of handling those issues and summarize their advantages and shortcomings.

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A study on the efficient supporting methods for small and medium businesses of mobile sector (모바일 분야 중소기업에 대한 효율적 지원 방안 연구)

  • Ahn, Jong-Chang;Lee, Dong-Han;Jung, Gag-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.2
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    • pp.192-201
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    • 2018
  • This study intends to find efficient support methods for small and medium-sized businesses (SMBs) especially in the increasingly important mobile sector. We investigated regarding perceptions of mobile sector-specific support programs and their current state of usage, and perceptions of the new mobile market and the present conditions of each stage of production based on analysis of a survey that included 204 respondents in each SMB to achieve this goal. Concretely, detections through this research were the reasons for non-selection of support businesses, the future prospective mobile business area, the company's own first-preference item and the reason for the preference, plus new mobile areas of willingness to apply the company's own product and its own first-preference item, and the reason for the preference. In addition, we found out covering costs and revenue size of the maximum-revenue product for each stage (from the first to the fourth stage), the kind of a product's execution method connected to the product (e.g. self-production, outsourcing to another company to produce a product), and the execution method for pre-products. We can suggest a policy regarding efficient support alternatives for SMBs related to the mobile sector thanks to these findings.

Presurgical Nasoalverolar Molding in Fraternal Twins with Bilateral Cleft Lip and/or Palate: A Case Report (양측성 구순/구개열을 가진 이란성 쌍둥이를 대상으로 한 술전 비치조정형술: 증례보고)

  • Kim, Jinsun;Kim, Youngjin;Nam, Soonhyeun;Kim, Hyunjung
    • Journal of the korean academy of Pediatric Dentistry
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    • v.41 no.1
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    • pp.72-79
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    • 2014
  • Cleft lip and palate(CLP) is one of the most common craniofacial deformities that requires systemic management involving a multidisciplinary team approach. Although there has been great improvement in the field of cleft surgery, surgical approach alone cannot resolve the various problems in treating cleft lip and palate. Hence the need for presurgical treatment was appreciated and especially, the concept of presurgical nasoalveolar molding was applied to treat unilateral and bilateral cleft lip and palate patients. Presurgical nasoalveolar molding(PNAM) of unilateral cleft mainly aims to recover nasal symmetry while the objectives of pre-surgical nasoalveolar molding in the bilateral cleft are to elongate the columella, to erect the tip of nose, and to reposition the forward displaced premaxillary region. This report covers the case of fraternal twins diagnosed with bilateral cleft. Retraction of the premaxillary region and nasoalveolar molding were conducted for 70 days until cheiloplasty, using elastic bands and nasoalveolar molding appliances. After cheiloplasty, there had been improvements in the length of columella and the position of forward-displaced premaxilla for both patients compared to their initial states. The esthetics was also satisfactory for both the surgery and the parents. In order to maximize the efficacy of the appliance, three components should be in balance; patients' adaptation to the appliance, parents' cooperation and proper selection and careful adjustment of the appliance by the dentist.

Classification of Recreation Forests through Cluster Analysis (군집분석을 통한 전국 자연휴양림 유형분류)

  • Lee, Kee-Cheol;Kang, Kee-Rae
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.1
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    • pp.9-17
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    • 2009
  • Twenty years have passed since the adoption of natural recreation forests and each forest has its own characteristics. However, there is hardly any classification among the natural recreation forests. The purpose of this study is to classify the forests by considering the supplier's perspective as well as the user's perspective in order to provide fundamental materials for the operation of the natural recreation forests. A factor analysis was conducted to identify the common characteristics of the selected twelve variables by pre-selection and survey of experts. K-means cluster analysis was conducted among those factors to classify the natural recreation forests in Korea. Four factors were drawn after the factor analysis and the factors were named according to the variables and sizes as 'The use performance and visiting condition factor', 'Education and settlement factor', 'Internal activation factor' and 'Potential factor' In addition, the cluster analysis of an $85{\times}4$ matrix was conducted for the points of the drawn factors and the final classification consists of five groups. The results of this study may contribute to providing fundamental materials for the operation and management of natural recreation forests. Also, it may act as a reference when investigating the natural recreation forests of Korea. Proposing the classification natural recreation forests could be helpful in selecting the proper recreation forest in the future. Based on the established model, fundamental materials could be provided to improve the profitability of the natural recreation forests by effectively expanding the number of tourists, creating new natural recreation forests and proper maintenance and management.

A Study on Development of Network Management Systems base on Component (컴포넌트 기반의 망관리 시스템 개발에 관한 연구)

  • Kim, Haeng-Kon;Kim, Ji-Young
    • The KIPS Transactions:PartD
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    • v.11D no.4
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    • pp.937-950
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    • 2004
  • With growing population of internet and web applications, distributed environment is considered to be the standard architecture of application. A network management systems(NMS) is necessary to control and monitor the complex network resources for providing and sharing the heft quality service. We recognize the NMS as a standard infrastructure for supporting efficient networking and a separate commercial applications. We believe every resource including software, hardware and environment for the network management should be separated from special protocols, vendors and applications. Therefore, We need a standard network management system that is efficient and consistent because of the heterogeous network features. In regards to software development, software reuse through assembling and extending the reusable elements such as patterns and components assures to realize the best productivity and quality The component based development(CBD) methodology that can assemble black box though well defined interfaces makes it possible to develop easer and quicker applications and is proved as the best software development solution involved in construction, selection and assembly of components. In this thesis, we describe the architecture for the network management and identify, define and design the components through analysis and design in the network management domain and Identified components mapped to the component architecture. We also specify the component development and design and implement the component for developing the network management. Implemented components apply to the component repository system that register, retrieve and understand the components. We analyze, design and implement the entire network management system based on configuration, connection, performance and fault management through the pre-developed components.

Performance-Oriented Procurement Process and VE/PSC for Private Finance Initiatives (민간투자사업의 성능중심적 발주방식 및 PSC의 활용방안)

  • Lim Jong-Kwon;Park Heung-Min;Jung Kun-Ho;Woo Ji-Won
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2004.11a
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    • pp.51-58
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    • 2004
  • The input-oriented project promotion system private participation in infrastructure projects currently in use in Korea has encountered difficulties in securing the primary benefits of private sector creativity problem solving and inflow of private capital. As such, the performance (or output)-oriented procurement process implemented in England and other developed countries should be evaluated for introduction. In Korea, private participation projects are currently identified as either solicited or unsolicited projects, each with different promotional procedures, the problem with these procedures is that competition is not pre-activated, the private sectors creativity is under utilized, and the rationality of project evaluations is inconsistent. Korea should, in order to raise the level of private sector creativity and efficiency, go beyond the currently applied Input Specification project promotion system to a Performance-oriented system similar to those implemented in England and other countries. To achieve this, we mate several proposals for the introduction of the performance-oriented system. We divide the main features of our proposals into three categories, including a reformed concessionaire selection system, a performance orientation in preparation of the concession agreement, and a performance orientation in contract management, and discuss each. 1'his study describes performance-oriented promotion systems in an output-focused way As this is an initial study on the introduction of performance orientation in private participation, various key points and proposals were identified. However, in the future, detailed research in technical fields and systems, legal research, and practical projects will be needed for implementation

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A Case Study of Multidisciplinary Integrated Science Lesson by Beginning Teacher and Experienced Teacher in Elementary Schools (초등학교 초임 교사와 경력 교사의 다학문적 통합과학 수업 사례 분석)

  • Lee, Yu-Mi;Son, Yeon-A
    • Journal of Korean Elementary Science Education
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    • v.29 no.4
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    • pp.552-566
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    • 2010
  • This paper is an in-depth case study to analyze integrated elementary science lesson planning and practical teaching by two teachers at an urban elementary schools. One is an experienced teacher and the other is a beginning teacher. For this study, researchers asked teachers to design 5 stages of lesson planning after sharing basic theories about the integrated science education. The first of the 5 lesson planning stages is curriculum analysis and choice of integrated science topic. The second stage is constructing the frame of integrated science lesson contents, and the third is drawing a diagram of the integrated science lesson development. The fourth stage is making a table of lesson plans, and the last stage is writing integrated science lesson plans. Then, the teachers implemented the lessons they created. They taught students one unit of science which is composed of 8 lessons. Difficulties that teachers meet during designing plans and integrated science class were analyzed. 5 staged lesson planning, video transcriptions, teacher interview about lesson planning and teaching, researchers' checklists, reports of inspection classes, teachers' self evaluation, and students interviews were used for this study. One of the significant results of this study is that both experienced and beginning teachers had many difficulties in deciding on time to teach and contents of science and other subjects, as well as selection and organization of whole topics of integrated science teaching. The beginning teacher especially had greater issues with developing definite teaching-learning strategy to conduct thoughts and views for integrated science at the whole unit and each lesson. However, the experienced teacher was using various teaching-learning strategies by utilizing integrated science teaching professionalism to develop students' integrated thinking ability during the instruction of other subjects. The outcomes of this study are that both teachers could deeply understand the need and value of integrated science education at the elementary school through planning and teaching 8 lessons, and that they could have self-confidence with development of teaching professionalism for integrated science teaching. It may be possible that this study could help the development of pre- and in-service program for improvement of integrated science teaching professionalism for elementary school teacher.

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The effects of storytelling techniques in the sex education on sound sexual value of Middle school students - Focused on the contents of the unit of 'Understanding of Adolescents' in Technology.Home Economics Textbook in Middle School - (스토리텔링 기법을 적용한 성교육이 중학생의 건강한 성가치관 형성에 미치는 효과 - 기술.가정 교과 '청소년의 이해' 단원을 중심으로 -)

  • Kang, So-Jeong;Cho, Byung-Eun
    • Journal of Korean Home Economics Education Association
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    • v.25 no.1
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    • pp.15-36
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    • 2013
  • This study aimed to identify the effects of using storytelling techniques in sex education, in which students are encouraged to talk about their experiences with sex and love and helps them form their own sex values and decision-making skills related to sex. A five-period teaching-learning plan covering issues including safe, considerate and responsible sex was developed using the storytelling technique for 134 first-year students in 4 classes. 134 questionnaires were administrated through pre-and post-test and 38 worksheets applying a variety of storytelling activities were analyzed using content analysis. Students were found to have gained a more positive outlook on relationships and a considerate attitude towards others in sex. There was also a significant increase in items considering safe sex, including perceptions on contraception methods and selection of safe contraception methods. The students' sense of sexual responsibility was also enhanced. Results of content analysis found students to have shifted to sex focusing on love and responsibility, and to have grown a stronger sense of responsibility in their relationships. Furthermore, the respondents expressed interest in selecting proper contraception methods and held strongly negative perceptions about abortion.

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Analyzing the Effect of Argumentation Program for Improving Teachers' Conceptions of Evolution (교사들의 진화 개념 이해 향상을 위한 논변활동 프로그램 효과 분석)

  • Kwon, Jieun;Cha, Heeyoung
    • Journal of The Korean Association For Science Education
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    • v.35 no.4
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    • pp.691-707
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    • 2015
  • This study aims to develop biology teachers' education program based on argumentation activity about core concepts of evolution and to analyze the characteristics of core concepts of evolution learned during the program. The eight core concepts of evolution in this study were variation, heritability of variation, competition, natural selection, adaptation, differential reproductive rate of individuals, changes in genetic pool within a population, and macroevolution. The performances of teachers participating in the program were compared before and after argumentation activities; consisting of seven sessions on the eight core concepts of evolution. The process of the program was specially designed by learning cycle model for teacher education, consisting of seven phases: identification of the task, production of a tentative argument, small group's written argument, share arguments with the other groups, reflective discussion, final written argument, and organization by an instructor. Participants in the study were two pre-service biology teachers and four in-service biology teachers. The results suggest that biology teachers reduced the teleological explanation for biological evolution and improve its adequacy after the intervention. Teachers lacked the opportunity to discuss variation, heritability of variation, competition, and macroevolution because science textbooks lack information on the concepts of biological evolution. The results of this study suggest that because the argumentation program developed for teachers helps to improve understanding the concepts of evolution and to reduce inadequate conceptions in biology, teacher education programs using argumentation activity and eight core concepts of evolution will play a role for efficient evolution education for biology teachers.