• 제목/요약/키워드: environment fit

검색결과 754건 처리시간 0.025초

RFID와 PDA를 이용한 측량 기준점 체계 개발 (Development of Intelligent Control Point System using RFID & PDA System)

  • 오윤석;곽태석;조한근;김창우;구지희
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2007년도 춘계학술발표회 논문집
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    • pp.31-35
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    • 2007
  • RFID is going to be the core technology for contact-less information transfer means in the era of ubiquitous. Up until recent days, the RFID didn't fit to be used in outdoor environment due to the fact that it was developed for logistics which does not require stability in outdoor. But recently, requests for the RFID to be used in the outdoor environment have increased, and this laid the foundation for the development of outdoor tags, including MetalTag, which can be utilized in many different ways. In this research, to provide information on the control point using the RFID at the sight, RFID tags, which can place at the control point, and PDA based system were developed.

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A Comparison of Optimization Algorithms: An Assessment of Hydrodynamic Coefficients

  • Kim, Daewon
    • 해양환경안전학회지
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    • 제24권3호
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    • pp.295-301
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    • 2018
  • This study compares optimization algorithms for efficient estimations of ship's hydrodynamic coefficients. Two constrained algorithms, the interior point and the sequential quadratic programming, are compared for the estimation. Mathematical optimization is designed to get optimal hydrodynamic coefficients for modelling a ship, and benchmark data are collected from sea trials of a training ship. A calibration for environmental influence and a sensitivity analysis for efficiency are carried out prior to implementing the optimization. The optimization is composed of three steps considering correlation between coefficients and manoeuvre characteristics. Manoeuvre characteristics of simulation results for both sets of optimized coefficients are close to each other, and they are also fit to the benchmark data. However, this similarity interferes with the comparison, and it is supposed that optimization conditions, such as designed variables and constraints, are not sufficient to compare them strictly. An enhanced optimization with additional sea trial measurement data should be carried out in future studies.

Using Structural Equation Modeling to Fit a Model of Student Background, Teacher Background, Home Environment, and a School Characteristic to Mathematics Achievement on the TIMSS

  • Cho, Gyu-Pan
    • 한국수학교육학회지시리즈D:수학교육연구
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    • 제7권4호
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    • pp.247-270
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    • 2003
  • The purpose of this study is to build a model that explains the relationship between and among five variables that are student background, teacher background, home environment, school characteristic, and student mathematics achievement, using structural equation modeling. Another purpose of this study is to compare the relationships of these variables between the United States and Korea in 7th and 8th grades mathematics. Student, teacher, and school background files from population 2 in the TIMSS were selected for this study. The result of the study provides practical information for teachers, parents, school principals, and other people who are interested in improving student achievement, and also provides the information that may explain differences and similarities between the US and Korea in mathematics achievement.

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성공적인 바이오벤처의 경영전략 (Strategy for the Successful Bio-venture in GMO Environment)

  • 박한오
    • 한국식물생명공학회:학술대회논문집
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    • 한국식물생명공학회 2003년도 식물바이오벤처 페스티발
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    • pp.31-36
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    • 2003
  • Bio-venture companies have undertaken harsh environment after 2000 bubble corruption. It is unlike to be changed in the near future. The business model of near-term cash flow, financial stability and survival is a key issue to be discussed. The company shall be rearranged to achieve fast recovery from investment and have to show clear and quantitative business model to the investors. Nevertheless, bio-venture should not drop long-term value creation by sacrificing the possibility of emerging technologies. Prior to clarifing agro-bioventure business model, GMO strategy should have broad supports from stakeholders. The interests and worries of stakeholders are discussed and SWOT is analyzed. For sustainable economy of future, new technology continuously should be invested to fit ROI model of genomics-based GMO developments. Hybrid of products ${\varepsilon}$ technologies may be one of the favorites in this stormy season.

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가상현실 선박 시뮬레이터의 배경 구현 (Implementation of Background Scene in the Virtual Reality Ship Simulator)

  • 임정빈
    • 해양환경안전학회지
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    • 제6권1호
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    • pp.11-22
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    • 2000
  • The paper describes creation methods of background scenes to implement realistic virtual environments in the VRSS (Virtual Reality Ship Simulator). VRSS is next-generation system constructed with virtual tools in a virtual space. Thus, it could have many benefits compared to conventional ship simulators composed with heavy bridge mock-up system and wide visual presentations. In this work, we developed effective 3D object modeling techniques, and constructed virtual harbor scene by using 3D-Webmaster authoring tool. The virtual harbor was built with object-oriented 3D objects modeled to interact with user's action. With the immersion-type VR system, we created virtual harbor environments in a virtual space, and discussed on the naturalness of the scene with test results of SDMPA (Semantic Differential Method for Psychophysical Assessment) by 10 subjects. As the results of subject assessment, all of the participants could felt natural-like harbor. Therefore, we found that the proposed creation methods and procedures of background scene are enabling to fit to the full mission VRSS construction.

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지방자치시대의 농촌지도업무의 변화와 방향 (Trends and Directions of Agricultural Extension Services under the Local Autonomy Period in Korea)

  • 이용환
    • 농촌지도와개발
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    • 제7권1호
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    • pp.45-64
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    • 2000
  • The purposes of the study were to identify the present status of the agricultural extension services in Korea and its surrounding environment, and to search the desirable ways of improvement under the serious restructuring period occurred by the nation-wide localization, globalization and development of information technology. Agricultural extension services have made great accomplishment in the education for rural people and agricultural technology diffusion, but agricultural extension service system no longer well fits in the changed environment. Agricultural extension services in Korea should restructure the system, function and methods in order to cope with the changing technology and rural society. The objectives of the extension services should be clear and simplified so that the extension workers can understand their role and duty more clearly. The local governments should encourage the extension workers to carry out their services diligently and with the pride. Also, the extension workers should change their mind to fit in the changing world and should improve their capability for their services.

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토양 슬러리내에 수착된 phenanthrene의 생물학적 이용성 (Bioavailability of sorbed phenanthrene in soil slurries)

  • 신원식;김영규;김영훈;송동익
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.92-95
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    • 2002
  • Bioavailability study was conducted to elucidate the relationship between sorption/desorption and biodegradation of sorbed phenanthrene in seven different soils. Mineralization kinetics was determined for phenanthrene-sorbed soil slurries inoculated with Pseudomonas putida (ATCC strain 17484). Two biodegradation models were used to fit mineralization kinetics; (i) a first-order degradation model and (ii) a coupled degradation-desorption model. The biodegradation rates were in order of vermicompost >Bion peat > 50% organoclay > Pahokee > blank (no soil, medium only) > montmorillonite > Ohio shale. The mineralization rate constants increased as desorption-resistance of phenanthrene increased. Among the tested sorbents, active biodegradation of phenanthrene was observed in vermicompost and Bion peat. Biodegradation in these two sorbents exhibited little lag time and a high maximum mineralized capacity. The role of sorption/desorption in bioavailability of phenanthrene sorbed in soils was discussed.

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폐광산 폐석에 의한 환경오염 저감기술 개발 기초 연구

  • 고주인;지상우;이현석;전용원;강희태;김선준
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 추계학술발표회
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    • pp.386-390
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    • 2003
  • To evaluate the potential capacity of mine wastes in the production of heavy metal containing acid water, samples from depths of 0, 30 and 60cm were collected and analyzed. The waste from surface showed the lowest pH which indicates the oxidation of wastes and the capacity of contamination of the area around the waste file. And the lower pH values of leachate of the wastes through the leaching tests with pH controlled water(3, 4, 5) may indicate that minerals producing the acidity still exist. Reduction of sulfur contents in wastes after the leaching test well fit to the increased contents of iron oxide.

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Environmental Dependence of Luminosity-Size Relation of Local Galaxies

  • Ann, Hong Bae
    • 한국지구과학회지
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    • 제38권5호
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    • pp.333-344
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    • 2017
  • We present the environmental dependence of the luminosity-size relation of galaxies in the local universe (z < 0.01) along with their dependence on galaxy morphology represented by five broad types (E, dEs, S0, Sp, and Irr). The environmental parameters we consider are the local background density and the group/cluster membership together with the clustercenteric distance for the Virgo cluster galaxies. We derive the regression coefficient (${\beta}$), i.e., the slope of the line representing the least-squares fitting to the data and the Pearson correlation coefficient (c.c.) representing the goodness of the least-squares fit along with the confidence interval from bootstrap resampling. We find no significant dependence of the luminosity-size relation on galaxy morphology. However, there is a weak dependence of the luminosity-size relations on the environment of galaxies, in the sense that galaxies in the low density environment have shallower slopes than galaxies in the high density regions except for elliptical galaxies that show an opposite trend.

테이블 구동 DSR을 이용한 에드혹 라우팅 프로토콜에 관한 연구 (A Study on Ad-Hoc Routing Protocol using Table-Driven DSR)

  • 유기홍;하재승
    • 한국컴퓨터산업학회논문지
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    • 제2권9호
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    • pp.1209-1218
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    • 2001
  • 본 논문은 이동 Ad Hoc 망 라우팅 프로토콜 중, 비대칭 경로를 지원하는 동적 소스 라우팅 프로토콜에 관한 연구이다. 기존의 동적 소스 라우팅 프로토콜은 양방향 경로만을 사용하도록 구현되어있다. 그러나 실제적인 무선환경에서는 단말의 비대칭성이나 무선환경 특성 등에 기인한 단방향 링크가 존재할 수 있다. 따라서 본 논문에서는 좀 더 일반적인 무선환경에 맞는 이동 Ad Hoc 망 라우팅 프로토콜을 구현하기 위하여 비대칭 경로를 지원하도록 하였다. 특히 이동성으로 인한 경로 실패를 인식한 경우, 신속한 경로 재설정을 수행하기 위해 개선된 다중경로유지 기법을 사용하였다.

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