• Title/Summary/Keyword: Scale-model

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Littoral Drift by the combined impact of Wind, Wave and Current ant the coastal Development Environment (해안개발환경하에서 바람 ${\cdot}$ 파랑 ${\cdot}$ 흐름의 중첩에 의한 연안표사)

  • Lee, Seung-Chul;Lee, Joong-Woo;Kim, Ki-Dam;Kang, Seok-Jin
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.141-142
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    • 2007
  • In recent years, the rate of mean sea level rise is increasing rapidly from the phenomena of global warming, together with the increasing trend of the storm scale. The issue of sea level rise is multifaceted and produces a range of environmental problems. Especially, high tides and the tidal currents become higher, and wave base increases, so the energy received at the coastal boundary may increase. This brings that many coastal environments go into disequilibrium, such as damages to the structures, erosion, and deposition Similarly it was known that the problems of nearshore processes and damage of berth and counter facilities during storm period had appeared at the small fishery port. Here we try to analyze the impact of the rearrangement of counter facilities and berth layout adopted for tranquility of its'inner harbor. Because this harbor is being connected to channel and open sea, the rearrangement of the structures might affect to the current speed and direction and wave height, so do to the sea bottom undulation. Therefore, we made model test for the several layouts of the berth and breakwater in this area.

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An Efficient Algorithm for Betweenness Centrality Estimation in Social Networks (사회관계망에서 매개 중심도 추정을 위한 효율적인 알고리즘)

  • Shin, Soo-Jin;Kim, Yong-Hwan;Kim, Chan-Myung;Han, Youn-Hee
    • KIPS Transactions on Software and Data Engineering
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    • v.4 no.1
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    • pp.37-44
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    • 2015
  • In traditional social network analysis, the betweenness centrality measure has been heavily used to identify the relative importance of nodes. Since the time complexity to calculate the betweenness centrality is very high, however, it is difficult to get it of each node in large-scale social network where there are so many nodes and edges. In our past study, we defined a new type of network, called the expanded ego network, which is built only with each node's local information, i.e., neighbor information of the node's neighbor nodes, and also defined a new measure, called the expanded ego betweenness centrality. In this paper, We propose algorithm that quickly computes expanded ego betweenness centrality by exploiting structural properties of expanded ego network. Through the experiment with virtual network used Barab$\acute{a}$si-Albert network model to represent the generic social network and facebook network to represent actual social network, We show that the node's importance rank based on the expanded ego betweenness centrality has high similarity with that the node's importance rank based on the existing betweenness centrality. We also show that the proposed algorithm computes the expanded ego betweenness centrality quickly than existing algorithm.

Public Officials' Perceptions on Improving Quality of Community Health Care Service (공무원 인식유형에 따른 보건서비스 개선 방안)

  • Yang, Chang Hoon;Lee, Jei Young
    • The Journal of the Korea Contents Association
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    • v.14 no.1
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    • pp.223-237
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    • 2014
  • The purpose of this study is to understand the perceptions of public officials in improving primary health care service for local communities by applying Q methodology that draw upon schematic model in subjectivity study. A survey was carried out among public officials at Gangneung Community Health Center, South Korea, to classify the 49 selected Q-statements into a normal distribution using a 11 point scale. The collected data was analyzed using QUANL program, and principal component factor analysis using varimax rotation was used to identify public officials' perceptions of improving quality of health care for local communities as a meaningful service provider. Type I can be categorized by a strong concern for the service acceptance, Type II can be categorized by advocating for service usability, Type III can be categorized by the pursuit of service specialization, Type IV can be categorized by roles for service accessibility, and Type V can be categorized by the suggestions for operation and management. The results provide information used to further improve quality of community health care service with the aim to promote the effectiveness of health care delivery and to increase health service utilization.

Development of Landscape Resource Assesment Systems of Jeju Island's Stonewall Fencing Farming Land for the Introduction of Direct Payment System of the Landscape Preservation and its Application (제주밭담의 경관보전직불제 도입을 위한 경관자원(제주밭담) 평가시스템 구축과 적용)

  • Ko, Seong-Bo
    • Journal of Korean Society of Rural Planning
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    • v.13 no.3
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    • pp.123-133
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    • 2007
  • The purpose of this study is to develop the landscape resource assessment system(LRAS) to help evaluate the value of landscape resources(Jeju Island's Stonewall fencing farming land) for the introduction of direct payment system of the landscape preservation objectively and to applicate the model in the fields. Delphi survey on Jeju's stonewall experts shows that the order of priority among value evaluation elements on Jeju's stonewall is its harmony with surroundings(34%), the preservation of its original state(34%) and its density and scale(32%). Evaluation system development of landscape resources(Jeju's stonewall fencing filming land) and field observation survey utilizing it consists of the following five steps. Step 1 includes the first Delphi survey on Jeju's stonewall experts to decide its value evaluation elements and their priority. Step 2 is the second Delphi survey on Jeju's stonewall experts to grade pictures of landscape resources(Jeju's stonewall fencing farming land) on the basis of expert-proposed value evaluation standards. Step 3 consists of analysis work using the result of Delphi survey on experts. Step 4 is to select five grade standard pictures according to each of three grading elements of A, B, C belonging to each of the three standards. Then, it is necessary to make panels including five A-grade pictures, five B-grade pictures and five C-grade pictures according to each of the three elements of density, harmony, and original state preservation. Step 5 consists of field observation survey. According to the result of few experts' value evaluation of stonewall fencing farming land with the aid of NRAS developed in this research, the area of Pyeongdae-ri is ranked first, and then the area of Bukcheon-ri, Chocheon-up, the area of Gwakgi-ri, Ewol-up, the area of Shinum-ri, Ewol-up and the area of Yongsu-ri, hankyung-Myun are ranked in the order named. When those areas are graded, A Grade Areas includes the areas of Pyeongdae-ri, the area of Bukcheon-ri, the area of Gwakgi-ri, B Grade Areas consist of the area of Shinum-ri and the area of Yongsu-ri, and the areas of Onpyeong, wimi and youngrak belong to C Grade Area.

High Resolution InSAR Phase Simulation using DSM in Urban Areas (도심지역 DSM을 이용한 고해상도 InSAR 위상 시뮬레이션)

  • Yoon, Geun-Won;Kim, Sang-Wan;Lee, Yong-Woong;Lee, Dong-Cheon;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.27 no.2
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    • pp.181-190
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    • 2011
  • Since the radar satellite missions such as TerraSAR-X and COSMO-SkyMed were launched in 2007, the spatial resolution of spaceborne SAR(Synthetic Aperture Radar) images reaches about 1 meter at spotlight mode. In 2011, the first Korean SAR satellite, KOMPSAT-5, will be launched, operating at X-band with the highest spatial resolution of 1 m as well. The improved spatial resolution of state-of-the-art SAR sensor suggests expanding InSAR(Interferometric SAR) analysis in urban monitoring. By the way, the shadow and layover phenomena are more prominent in urban areas due to building structure because of inherent side-looking geometry of SAR system. Up to date the most conventional algorithms do not consider the return signals at the frontage of building during InSAR phase and SAR intensity simulation. In this study the new algorithm introducing multi-scattering in layover region is proposed for phase and intensity simulation, which is utilized a precise LIDAR DSM(Digital Surface Model) in urban areas. The InSAR phases simulated by the proposed method are compared with TerraSAR-X spotlight data. As a result, both InSAR phases are well matched, even in layover areas. This study will be applied to urban monitoring using high resolution SAR data, in terms of change detection and displacement monitoring at the scale of building unit.

Evaluation of the Relationship between Geogrid Rib Size and Particle Size Distribution of Ballast Materials using Discrete Element Method (개별요소해석법을 이용한 지오그리드 격자 크기와 도상자갈재료 입도분포 상관관계 평가)

  • Pi, Ji-Hyun;Oh, Jeongho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.1
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    • pp.143-149
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    • 2016
  • This study evaluated the shear behavior of geogrid reinforced ballast material using a large scale direct shear test and discrete element method (DEM) based on PFC 3D program. The direct shear test was conducted on ballast materials that have different particle size distributions. Whereas the test results revealed that the shear strength generally increased with the larger particle size of ballast material without geogrid reinforcement, the shear behavior of ballast material was found to change pertaining to the relationship between particle size distribution and geogrid rib size. Generally, it is deemed the effectiveness of reinforcement can be achieved when the rib size is two times greater than average particle size. A numerical analysis based on DEM was conducted to verify the test results. The geogrid modeling was successfully completed by calibration process along with sensitivity analysis to have actual tensile strength provided by manufacturer. With a given geogrid model, the parametric evaluation was further carried out to examine the interactive behavior between geogrid and ballast material. Consequently, it was found that the effectiveness zone of geogrid reinforcement generated within a specific depth.

The Development of STEAM Program with the Unit 'Energy and Transportation Technology' on the Subject of Technology.Home Economics (기술.가정 교과 '에너지와 수송 기술' 단원에서 활용할 STEAM 프로그램 개발)

  • Kim, Ki Yeol;Ham, Hyung In;Kim, Ki Soo
    • 대한공업교육학회지
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    • v.38 no.1
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    • pp.29-48
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    • 2013
  • The purpose of this research is to provide a desirable case of STEAM education utilizing 'Energy and Transportation Technology' unit on the subject of technology home economics. The middle school students learned with the integrated approach based on STEAM integrated education, and through production process they had the opportunity for application and expression in diverse forms. The results of this process to achieve the purpose are as follows. First, as the procedural model to develop STEAM program utilizing 'Energy and Transportation Technology' unit on the subject of technology home economics, the five stages: preparation, development, verification, practice, and evaluation, were presented. The preparation stage was composed of requirement analysis, the selection of program subject, and STEAM program curriculum analysis, the selection and organization of STEAM program lesson. The development stage was composed of the development of lesson plan, multimedia teaching materials, worksheet and worksheet answer key. In the verification stage, the verification of validity by experts was conducted, and in the practice stage, the developed program was applied to the middle school students in the educational field, and in the evaluation stage, based on the evaluations received from learners and teachers, it was revised and supplemented. Second, the STEAM program was developed into the program summary map, lesson plan, multimedia teaching materials, worksheet and worksheet answer, etc., and after the validity was secured through experts' verification, it was revised and supplemented and applied to actual classes. Third, the results of the learners' evaluation of the developed STEAM program showed that the degree of satisfaction with the program was high with the average score of the entire questions being 4.00 on a five-point scale. As the teachers also evaluated the developed STEAM program as very effective, the opinions of learners and teachers were collected and the program was finally improved and completed.

A Trial for Development of Health Profile (KHP 1.0) to Measure the Self-Perceived Health Status of Korean (한국인의 자가평가 건강수준 측정도구(KHP 1.0) 개발)

  • Yang, Jin-Sun;Chun, Jin-Ho
    • Journal of Preventive Medicine and Public Health
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    • v.36 no.1
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    • pp.11-23
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    • 2003
  • Objectives : The 1990s has seen advances in the conceptualization of self-perceived health status which has important roles for individual health and the quality of life. Many types of standardized questionnaires have been developed with the current wide use of SF-36, NHP, andEuroQol. However, the outcomes of these tools may be different with regard to regional, cultural and emotional backgrounds. The purpose of this study was to trial the development of a Korean Health Profile (KHP 1.0) to measure the self-perceived health stati of Koreans. Methods : The KHP 1.0 was designed on the basis of the Medical Outcome Study Form 36 (SF-36), the Nottingham Health Profile (NHP), and the EuroQOL. It was composed of 9 scales; physical functioning, role limitation-physical, pain, general health, energy, social isolation, sleep, role limitation-emotional, and e-motional health. Self-reported chronic disease conditions, and the Zung's Self-Rating Depression Scale (SDS), were also checked for the evaluation of clinical validity. This study was conducted, from December 2000 to January 2001, on 800 middle-aged parents, with four high school students, with 100 retest sets being conducted two weeks later. From the 800 subjects there were 588 complete responses (effective response 73.5%). The reliability of the test-retest results, and the factor analysis on the validity of the KHP 1.0 components, were evaluated using the SPSS (ver 10.0) software. Results : The reliability of the KHP 1.0 was good with Cronbach's alpha (>0.6), test-retest correlation coefficients (>0.5), but with no significant differences from the paired t-test. From the psychometric validity tests, the 9 scales of the KHP 1.0 were divided into two components; physical and mental, and trimmed to the established model with 55% of the total variance, with the exception of role limitation-emotional. The clinical validity on the basis of the comparison for the four characteristic groups; healthy, physical conditions only, mental conditions only, and physical and mental conditions were also good. Conclusions : The KHP 1.0 appears to be a valid measurement tool of self-perceived health stati of Koreans, although there are limitations, i.e. sample size was too small, a limited number of middle-aged subjects, and it was based on unconfirmed diagnoses, etc. Therefore, further study is required to standardize the assessment.

Measurement of Motivation to Learn Physics in Engineering College Students (공학계열 대학생의 물리학습동기 측정)

  • Mun, Kongju;Hwang, Yohan;Ha, Minsu
    • Journal of Science Education
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    • v.44 no.1
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    • pp.74-83
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    • 2020
  • The purpose of this study is to investigate motivation to learn physics in order to understand engineering college students' physics learning. Therefore, in this study, 374 engineering students at the university located in Seoul were studied using the Physics Motivation Questionnaire (PMQ), which was a Science Motivation Questionnaire II modified into the context of learning physics. The PMQ is composed of five factors: intrinsic motivation, career motivation, self-determination, self-efficacy, and grade motivation. It involves 25 Likert scale items. Through exploratory factor analysis, PMQ confirms that the five factors are structurally valid in measuring the motivation of engineering students to learn physics. In addition, item fit (MNSQ) was also confirmed using a Rasch model analysis. The results show that grade motivation has the highest mean with 4.2, followed by job motivation mean with 3.76. The mean of intrinsic motivation was 3.42, the self-efficacy was 3.38, and self-determination was 3.32. The results of this study confirm that the physics learning motivation of engineering college students is characterized showing high external motivation related to job and grade. Therefore, we should try to develop the teaching strategy to increase intrinsic motivation by developing mastery goal orientation of physics learning for engineering students.

A Study on the Location Factors of Foreign Direct Investment Firms in Korea (국내 외국인직접투자기업의 입지결정요인에 관한 연구)

  • Lee, Ho-Yeong;Park, Won-Seok
    • Journal of the Korean association of regional geographers
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    • v.17 no.1
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    • pp.58-74
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    • 2011
  • This study analyzed and compared the importance and priority of location decision factors in Foreign Direct Investment Firms managing the manufacturing business in the nation's southeastern economic zone, and in expert group by using AHP analytical technique based on examining the location theory and the prior research of real estate for industry. Also, it analyzed difference in importance and priority for location factors by corporate scale, by business category, and by location type targeting only foreign direct investment firms, and offered references necessary for location decision-making. In addition, to elicit useful information for policy related to location decision factors for foreign direct investment firms, the implications were elicited by analyzing the results recognized between foreign direct investment firms and expert group on information elements regarding investment satisfaction, business bottlenecks, and location decision process. The considerable gap was indicated in importance and priority of location decision factors considered between the nation's foreign direct investment firms and real-estate expert group for industry. As a result of analyzing by reflecting the corporate characteristic variable in location assessment model unlike before, the importance of the competitive advantage factor and the business strategic factor was indicated to be very high.

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