• Title/Summary/Keyword: 3D City model

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Development of Customer Safety Model of Unsignalized Intersections on the Community Road (생활도로내 비신호교차로 이용자 안전도 모형 개발 - 서울시 생활도로내 비신호교차로를 중심으로 -)

  • Lee, Hyeong Rok;Chang, Il Joon;Lee, Soo Beom;Kim, Jang Wook
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.3D
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    • pp.205-213
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    • 2010
  • The unsignalized intersections in a community road in the city of Seoul have 3,753 traffic accidents(9%) of total 41,702 cases in 2008, not high in the occurrence rate of traffic accidents, but seem to have a quite high potential of accidents due to the unreasonable and insufficient operation of systems and facilities in the part of traffic foundations. In particular, the un-signalized intersections in a community road have an insufficient measure for safety as compared to the crossroads with signals, and there are few analysis of traffic accidents and domestic researches on the model of affecting factors. Our country also has no concept of passing priority in operating a crossroad without signals, differently from foreign countries, so the researches and safety measures for improving the safety of a crossroad without signals in a community road are urgent. Therefore, this research has developed a safety model for a crossroad without signals in a community road based on the safety image data collected through individual interviews and questionnaires for the users of unsignalized intersections in a community road, and confirmed that legal systems, road facilities, personal factors, etc. have the biggest effect on the safety of drivers. It was confirmed that the clarity of passing methods, establishment of legal systems, etc. have the biggest effect on safety in order to raise the safety of unsignalized intersections in a community road, which drivers desire.

Relationships between Physical Activity, Health Status, and Quality of Life of University Students (대학생의 신체활동량, 건강상태 및 삶의 질과의 관계)

  • Park, Jee Yeon;Kim, Na Hyun
    • Journal of Korean Public Health Nursing
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    • v.27 no.1
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    • pp.153-165
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    • 2013
  • Purpose: The purpose of this study was to identify the relationships between physical activity, health status, and quality of life (QOL) of University students. Methods: The research design was based on a descriptive research design model. This study sample consisted of 183 K University students in D city. Data was collected from December 2012 to January 2013 and analyzed with descriptive statistics (frequency, percentage, analysis of variance (ANOVA), t-test, and Pearson's correlation analysis) using SPSS 19.0. Subjects completed questionnaires on their demographics, physical activity, health status, and QOL. Results: The overall physical activity of participants was $2529.40{\pm}5057.896$ min/week on average. The average health status was $28.66{\pm}6.3$ and the average physical health and mental health were $16.45{\pm}3.955$ and $12.31{\pm}3.446$, respectively. The overall degree of QOL was $3.429{\pm}0.379$. A positive relationship existed between moderate and vigorous activity and health status. In addition, QOL positively correlated with physical health (under health status). However, physical activity was not related with both mental health (under health status) and QOL. Conclusion: Based on the results of this study, health educational programs are needed to promote sufficient physical activity in university students.

A Comprehensive Model for Identification of Underachieved Gifted Children in Elementary Schools (복합판별 과정에 의한 초등학교에서의 미성취 영재 판별)

  • Pahk, So-Young;Lee, Jin-Hee
    • Journal of Gifted/Talented Education
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    • v.17 no.2
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    • pp.251-279
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    • 2007
  • The purpose of this study was to develop a comprehensive model to identify underachieved gifted children in elementary schools by utilizing multiple methods. From March 1st, 2006 through September 30th, 2006, we developed and applied a 6-step comprehensive identification model for underachieved gifted children by examining 1980 children attending S elementary school located in Daegu Metropolitan City, starting from the first step of teacher nomination to the last step of committee's final decision. As a result, 4 students were identified as underachieved gifted children. For comprehensive and appropriate identification, we adopted, adjusted, or developed several standardized tests, teacher nomination form, parental questionnaire, self-report checklist, and school achievement tests, which were fine-tuned in the application process of this identification model. Based on this study, we suggest that a comprehensive identification model for underachieved gifted children in public elementary schools consist of 6 steps: a) teacher nomination, b) simplified standardized testing, c) student's self-report, d) multiple standardized tests, e) qualitative analysis, and f) a committee decision for the final identification.

The Impact of COVID-19 on Health Prevention Behaviors in College Students: Focusing on the Health Belief Model (일부 대학생의 코로나19에 대한 건강예방행위에 미치는 영향: 건강신념모델을 중심으로)

  • Jo, Han-Ul;Choi, Eun-Hi
    • Journal of the Korean Society of School Health
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    • v.34 no.2
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    • pp.115-122
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    • 2021
  • Purpose: The purpose of this descriptive research is to identify how stress from Covid-19, health beliefs, and social support of college students affect health prevention. Methods: The subjects of the study were 128 university students, excluding health major students, at one university in D City. The survey was conducted from August 1 to 31, 2020. The survey questionnaire consists of 8 items on stress from COVID-19, 12 items adapted from a health belief measurement tool, 12 items from a social support measurement tool, and 11 items adapted from a tool that measures health preventive behaviors. The collected data were analyzed using the hierarchical multiple regression analysis method with SPSS 26.0. Results: In model 1, stress from COVID-19 was statistically significant (β=-.403, p=.003). Model 2 added four health belief factors into Model 1. Stress (β=-.419, p<.001), perceived severity (β=-.193, p=.030), and perceived barriers (β=-.182, p=.009) were statistically significant. In model 3, stress (β=-.413, p<.001), perceived barriers (β=-.147, p=.034), and social support (β=.194, p=.011) were statistically significant. The regression equation was significant (F=15.395, p=<.001) and the model's explanatory power was 53.1%. Conclusion: The results show that when college students had a high degree of health beliefs about COVID-19, the degree of health preventive behaviors was proportionally high. To make them practice preventive health behaviors, it is necessary to develop infection control education programs to improve health beliefs.

3D GIS Network Modeling of Indoor Building Space Using CAD Plans (CAD 도면을 이용한 건축물 내부 공간의 3차원 GIS 네트워크 모델링)

  • Kang Jung A;Yom Jee-Hong;Lee Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.23 no.4
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    • pp.375-384
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    • 2005
  • Three dimensional urban models are being increasingly applied for various purposes such as city planning, telecommunication cell planning, traffic analysis, environmental monitoring and disaster management. In recent years, technologies from CAD and GIS are being merged to find optimal solutions in three dimensional modeling of urban buildings. These solutions include modeling of the interior building space as well as its exterior shape visualization. Research and development effort in this area has been performed by scientists and engineers from Computer Graphics, CAD and GIS. Computer Graphics and CAD focussed on precise and efficient visualization, where as GIS emphasized on topology and spatial analysis. Complementary research effort is required for an effective model to serve both visualization and spatial analysis purposes. This study presents an efficient way of using the CAD plans included in the building register documents to reconstruct the internal space of buildings. Topological information was built in the geospatial database and merged with the geometric information of CAD plans. as well as other attributal data from the building register. The GIS network modeling method introduced in this study is expected to enable an effective 3 dimensional spatial analysis of building interior which is developing with increasing complexity and size.

Comparison and Evaluation on DEM Error by the Resolution of Airborne Laser Scanning Data (항공레이저 측량 자료의 해상도에 따른 DEM 오차 비교평가 연구)

  • Lee, Geun-Sang;Koh, Deuk-Koo;Chae, Hyo-Seok;Shin, Young-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.6 no.3
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    • pp.33-42
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    • 2003
  • As airborne laser scanning technique is developed with high vertical accuracy recently, there come many studies on DEM(digital elevation model creation, building extraction, flood risk mapping and 3D virtual city modeling. This study applied point comparative method, contour comparative method and digital map with scale 1/5,000 to calculate RMSE of DEM in according to resolution that was constructed using rawdata being acquired by airborne laser scanning. As a result, point comparative method showed lower DEM standard error than contour comparative method, it is a reason that contour comparative method was not carried out detailed grid calculation for point comparative method. Also, digital map with scale 1/5,000 showed higher DEM standard error than point comparative method and contour comparative method in below 25.4m that is average horizontal distance among contour line, and showed similar result with contour comparative method in over 25.4m.

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Progressive collapse analysis of a RC building subjected to blast loads

  • Almusallam, T.H.;Elsanadedy, H.M.;Abbas, H.;Alsayed, S.H.;Al-Salloum, Y.A.
    • Structural Engineering and Mechanics
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    • v.36 no.3
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    • pp.301-319
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    • 2010
  • The paper seeks to explore some aspects of the current state of knowledge on progressive collapse in the technical literature covering blast loads and structural analysis procedure applicable to reinforced concrete (RC) buildings. The paper describes the progressive collapse analysis of a commercial RC building located in the city of Riyadh and subjected to different blast scenarios. A 3-D finite element model of the structure was created using LS-DYNA, which uses explicit time integration algorithms for solution. Blast loads were treated as dynamic pressure-time history curves applied to the exterior elements. The inherent shortcomings of notional member removal have been taken care of in the present paper by simulating the damage of structural elements through the use of solid elements with the provision of element erosion. Effects of erosion and cratering are studied for different scenarios of the blast.

A Study on the Propagation Path Considering the Horizontal Alignment of Road (도로의 평면선형을 고려한 전파경로 분석)

  • Kim, Song-Min
    • 전자공학회논문지 IE
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    • v.44 no.1
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    • pp.27-32
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    • 2007
  • This study was to suggest the predictive model of propagation, considering the effect by the multipath waves produced by the sending and receiving vehicles' left/right reflectors and the adjacent vehicles when the communication between the vehicles on the one-way two-lanes road in the urban city with a lot of traffic jams. Then, the radius of curved road was 600[m], the length of curved roads $52.4\sim471.2[m]$, and the bridge's pier of road was $5o\sim45o$. Also, it was simulated by changing the receiving vehicle located on the curved road's gap from minimum 3.3[m] to maximum 29.5[m], corresponding to the change of distance of the bridge's pier of road and curved road. As a result of this research above, in case of $5o\sim15o$ bridge's pier of road, it was within l[dB] regardless of the receiving vehicle's position on the curved road in case of propagation path loss. In case of $15o\sim45o$, it was approximately $1\sim8[dB]$ as the bridge's pier of road is changed. And, in case of propagation path, it found out that it was changed to $0.4\sim120[m]$ according to the change of bridge's pier of road. Then, the delay time of propagation was 400[nsec] as it produced 120[m] in the difference of propagation path.

Derivation of System Requirements and Scenario for Smart Bridge Facility Management System Development (스마트 교량 관리시스템 개발을 위한 요구사항 및 활용 시나리오 도출)

  • Hong, Sungchul;Kang, Taewook;Hong, Changhee;Moon, Hyounseok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.11
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    • pp.7902-7909
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    • 2015
  • The needs for smart city management technology has been increased for efficiently managing huge and complex social infrastructures. Thus, this research introduces smart bridge facility management system based on sensor and BIM technologies so that the inadequacy of current facility maintenance system and the limitations of data objectivity, consistency and expandability can be improved. For which, current trends on sensor and BIM technologies and standard information system were investigated to derive system develop requirements, and a scenario was suggested to discuss how to utilize the suggested system. Research outcomes are expected to be utilized as a preliminary research for developing the real application framework for bridge facility management.

Effect of Soft Handoff Technique on CDMA Cell Coverage in a Lognormally Shadowed Channel (전파음영 채널 환경에서 소프트 핸드오프 기법이 CDMA 셀룰러 시스템의 셀 커버리지에 미치는 영향)

  • Oh, Hyon-Kyu;Kim, Hang-Rae;Kim, Nam
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.6
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    • pp.871-881
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    • 2001
  • In this paper, the effect of soft handoff technique on CDMA cell coverage is analyzed in a lognormally shadowed channel, which uses the Hata propagation model, Also, the rate of increase for the cell coverage is analyzed by calculating the hard and soft handoff margin. When the outage probability is 0.02 and the standard deviation of the received signal is 2.5 dB in a lognormally shadowed channel, the transmit power of the mobile station which is located in the cell boundary is increased by the hard handoff margin of 5.13 dB and by the soft handoff margin of 3.68 dB, respectively. So, the rate of increase for the cell coverage is 1.39 in case of using the soft handoff technique. It is shown that if the (E$\_$b//N$\_$0/)$\_$req/ value is 7 dB, the cell coverage of the CDMA cellular system with soft handoff technique in city area is 3.33 km in case of the 850 MHz frequency and 1.36 km in case of the 1900 MHz frequency. Also, the accurate cell coverage with soft handoff technique is supported that could be serviced by the base-station in CDMA cellular system.

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