• Title/Summary/Keyword: 연계성 지수

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Optimal control of power system frequency (전력계통 주파수의 최적제어에 관한 연구)

  • 박영문;이봉용;윤희용
    • 전기의세계
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    • v.28 no.6
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    • pp.52-60
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    • 1979
  • 이 논문은 전력계통의 자동주파수 최적제어를 위한 관측자시스템을 최적설계하는 체계적 방법을 연구한 결과를 기술한 것이다. 이 논문의 특징은 저차 루엔버그관측자시스템의 추정오차에 관한 새로운 평가척도를 정의한 후 이를 방복 알고리듬에 의하여 최소함으로써 측정불가능한 시스템 상태와 교란을 가능한 한 정확히 추정할 수 있는 즉 최적관측자를 구성하는 있으며, 특히 이 논문에서는 필자가 이미 발표한 최적 주파수제어방책과 지수교란모형을 그대로 도입하여 상기 목적을 실현할 수 있었다. 이 논문에서 제시한 방법을 검증하기위하여 다지역계통의 가장 간단한 형태라할 수 있는 2개지역이 연계된 자동주파수제어시스템을 대상으로 디지탈 시뮬레이션 한 결과, 이 방법의 장점과 실용성이 입증되었다.

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Analysis of technological competitiveness and technology-industry linkage structure of Korea, China and Japan utilizing the patent information in the field of biotechnology (생명공학분야 특허정보를 활용한 한.중.일 기술경쟁력 및 기술-산업연계구조 분석)

  • Cho, Sung-Do;Lee, Cheon-Mu;Hyun, Byung-Hwan
    • Journal of Technology Innovation
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    • v.21 no.1
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    • pp.141-163
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    • 2013
  • As the importance of biotechnology has been increased as a growth engine for country, most countries get focused on securing technological competitiveness in the field of biotechnology. Under the fierce global competition, it is very important to identify technological competitiveness of Korea and our neighboring countries in order to carry out effective research and development. Expert opinion survey such as Delphi is mainly conducted to analyze the technological competitiveness, but the method based on experts' intuition may produce different results depending on survey respondents due to the strong subjective inclination. In this study, the patent registered in US was utilized to analyze the technological competitiveness based on objective data. Targeting countries were Korea, China and Japan which were leading nations in the Northeast Asia. As analytical indexes, NP(Number of Patents), CPP(Cites per Patent), PII(Patent Impact Index), TS(Technology Strength), TI(Technology Independence), PFS(Patent Family Size) were used for analysis. Moreover, the industrial linkage with biotechnology was analyzed by matching IPC code of patents with 44 industries. Based on this analysis, technological convergence and utilization were quantified. The findings can be utilized as basic data when policy is established to improve technological competitiveness in the field of biotechnology.

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Vegetation Monitoring using Unmanned Aerial System based Visible, Near Infrared and Thermal Images (UAS 기반, 가시, 근적외 및 열적외 영상을 활용한 식생조사)

  • Lee, Yong-Chang
    • Journal of Cadastre & Land InformatiX
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    • v.48 no.1
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    • pp.71-91
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    • 2018
  • In recent years, application of UAV(Unmanned Aerial Vehicle) to seed sowing and pest control has been actively carried out in the field of agriculture. In this study, UAS(Unmanned Aerial System) is constructed by combining image sensor of various wavelength band and SfM((Structure from Motion) based image analysis technique in UAV. Utilization of UAS based vegetation survey was investigated and the applicability of precision farming was examined. For this purposes, a UAS consisting of a combination of a VIS_RGB(Visible Red, Green, and Blue) image sensor, a modified BG_NIR(Blue Green_Near Infrared Red) image sensor, and a TIR(Thermal Infrared Red) sensor with a wide bandwidth of $7.5{\mu}m$ to $13.5{\mu}m$ was constructed for a low cost UAV. In addition, a total of ten vegetation indices were selected to investigate the chlorophyll, nitrogen and water contents of plants with visible, near infrared, and infrared wavelength's image sensors. The images of each wavelength band for the test area were analyzed and the correlation between the distribution of vegetation index and the vegetation index were compared with status of the previously surveyed vegetation and ground cover. The ability to perform vegetation state detection using images obtained by mounting multiple image sensors on low cost UAV was investigated. As the utility of UAS equipped with VIS_RGB, BG_NIR and TIR image sensors on the low cost UAV has proven to be more economical and efficient than previous vegetation survey methods that depend on satellites and aerial images, is expected to be used in areas such as precision agriculture, water and forest research.

Experimental Investigation of Macroscopic Analysis of Traffic Safety Using Meta Analysis Focused on Busan Metropolitan City (메타분석을 이용한 교통안전성의 거시적 분석에 대한 실험적 고찰 : 부산광역시를 중심으로)

  • Park, Jongseo;Oh, Yun Pyo;Kim, Hoe Kyoung;Ahn, Woosung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.6
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    • pp.1339-1345
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    • 2015
  • Korean government annually estimates and reports the traffic safety index to evaluate the traffic safety of 228 Gu Gun. However, since the traffic safety index is derived from the spatially macroscopic perspective based on collected relative data, there are a couple of problems such as inability to investigate the individual traffic accidents on the spot, insecurity of accuracy and reliability of traffic safety index estimation method, and absence of establishing temporal relationship of traffic accidents. Thus, this study investigated temporal traffic safety in macroscopic manner for Gu Gun in Busan depending on the installation of the traffic safety facility (i.e., urban median), employing meta analysis. As a result, all Gu Gun in Busan except Saha, Buk, Dong, and Busanjin experienced more traffic accidents after installing the urban median, indicating that there are more rooms for improvement of macroscopic traffic safety evaluation.

Combined analysis of meteorological and hydrological drought for hydrological drought prediction and early response - Focussing on the 2022-23 drought in the Jeollanam-do - (수문학적 가뭄 예측과 조기대응을 위한 기상-수문학적 가뭄의 연계분석 - 2022~23 전남지역 가뭄을 대상으로)

  • Jeong, Minsu;Hong, Seok-Jae;Kim, Young-Jun;Yoon, Hyeon-Cheol;Lee, Joo-Heon
    • Journal of Korea Water Resources Association
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    • v.57 no.3
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    • pp.195-207
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    • 2024
  • This study selected major drought events that occurred in the Jeonnam region from 1991 to 2023, examining both meteorological and hydrological drought occurrence mechanisms. The daily drought index was calculated using rainfall and dam storage as input data, and the drought propagation characteristics from meteorological drought to hydrological drought were analyzed. The characteristics of the 2022-23 drought, which recently occurred in the Jeonnam region and caused serious damage, were evaluated. Compared to historical droughts, the duration of the hydrological drought for 2022-2023 lasted 334 days, the second longest after 2017-2018, the drought severity was evaluated as the most severe at -1.76. As a result of a linked analysis of SPI (StandQardized Precipitation Index), and SRSI (Standardized Reservoir Storage Index), it is possible to suggest a proactive utilization for SPI(6) to respond to hydrological drought. Furthermore, by confirming the similarity between SRSI and SPI(12) in long-term drought monitoring, the applicability of SPI(12) to hydrological drought monitoring in ungauged basins was also confirmed. Through this study, it was confirmed that the long-term dryness that occurs during the summer rainy season can transition into a serious level of hydrological drought. Therefore, for preemptive drought response, it is necessary to use real-time monitoring results of various drought indices and understand the propagation phenomenon from meteorological-agricultural-hydrological drought to secure a sufficient drought response period.

Ecological Assessment Technique of Connectivity to Disconnected Floodplains by Levee (격리차단된 제내지 하천환경의 생태적 연계성 평가 기술)

  • Cho, Kang-Hyun;Jin, Seung-Nam;Cho, Hyunsuk
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.7-7
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    • 2017
  • 범람파동 개념에 따르면 하도와 홍수터의 횡적 연결성은 하천 생태계의 생물다양성과 생산성 증대에 중요한 역할을 한다. 제방에 의하여 제내지 홍수터가 하도와 차단된 우리나라 하천에서 생태적 서비스를 증대하기 위해서 횡적 연결성을 복원하는 기술 개발이 필요하다. 횡적 연결성의 복원 기술을 개발하기 위해서는 우선 하도와 홍수터 사이에 생태적 연결성의 현황을 파악하고 연결성을 저해하는 요인을 진단하는 평가 기술 개발이 시급히 요청되고 있다. 따라서 본 연구에서는 제방에 의하여 차단된 제내지 하천환경에서 수리적, 생태적 횡적 연결성을 평가하고 진단하는 기술을 개발하고 연결성 회복 방안을 제안하고자 한다. 차단된 제내지 하천환경 평가는 1) 지리정보시스템을 이용하여 차단된 하천공간을 탐색하고, 2) 탐색된 전체 재내지에서 원격평가에 의하여 간편하게 횡적 연결성 평가를 실시하고, 3) 선정된 특정 제내지 대상지에서 현장평가에 의하여 상세하게 연결성을 평가하는 순서로 수행된다. 차단된 하천공간의 획정은 홍수가 범람할 수 있는 제내지 공간을 잠재적 하천공간으로 정의하고 수치표고모델 (DEM)과 하천기본계획의 30년 빈도 홍수위 자료를 이용하여 제내지 홍수터를 탐색하였다. 제내지 홍수터의 원격 연결성평가는 지리정보시스템에서 수치지도와 토지피복도 등 공간자료를 이용하여 수리 및 서식처 환경성, 제방 차단성과 하도 및 육상 연결성을 평가하고 원격평가 결과를 토대로 현장평가 대상지를 선정하였다. 횡적 연결성의 현장평가를 위하여 크게 하도-홍수터 연결성과 제내지 서식처 보존성으로 평가 항목을 선정하였다. 또한 연결성 평가는 수리연결성과 생물연결성으로, 서식처 보존성 평가는 습지유지율, 습지보존성, 육역지보존성을 세부항목으로 구성하였다. 평가 항목별로 5 등급의 평가 기준에 따라서 평가 점수를 부여하고 평가 총점을 산출하여 최종 연결성 평가 등급을 5 단계로 구분하였다. 현장평가를 위한 MS Access 기반 소프트웨어를 개발하여, 데이터 입력과 관리 및 평가 결과 산출과 비교를 편리하게 하였다. 개발된 제내지 하천환경 평가법을 청미천과 만경강에 적용하여 검증하였다. 개발된 평가법을 바탕으로 차단된 제내지 하천환경에서 연결성 회복에 따른 어류와 식생의 분포를 예측하는 수리생태 결합모델을 개발하였다. 먼저 차단된 제내지에서 연결 수로를 복원하여 유속, 수심 분포를 준이차 수리수문 모델로 예측하였다. 예측된 수리 환경에 따라서 지표어종의 서식처 적합도 지수 (HSI)를 이용하여 서식 분포 확률을 모의하였다. 또한 일반화가법모델 (GAM)을 이용하여 환경구배에 의한 우점식생의 분포를 예측하였다. 차단된 제내지 하천환경의 생태적 연계성 평가 기술을 기반으로 제방제거, 제방후퇴, 제방고 하강, 수문 및 연결수로 개선, 생물이동 저해 장벽 제거 등의 다양한 복원기술이 개발되어야 할 것으로 생각된다.

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A Study on the Fundamental Course of Multimedia Design (멀티미디어 디자인 교육의 기초 과정에 대한 연구)

  • 이지수
    • Archives of design research
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    • v.15 no.4
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    • pp.223-230
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    • 2002
  • As evolution of multimedia technology brings changes to industries concerned with design, new education program is needed to cultivate designers with abilities which are adapted to changed circumstance. This paper is purposed to show guideline to set up a fundamental course for multimedia design in which students know what are new presentation modes and learn how to use them, Multimedia design call for abilities of organizing information, representing, and implementing interactivity. Among them, fundamental course considers representing information as central subject. And it also contains lessons which are relative to proceeding courses. It should have students to experience creative composition and various expressions, and study cognitive or aesthetic effects of them. All activities are based on the understanding about presentation factors and principles. Basic course's lessons are composed by two main subjects, which are essential expression and matters relative to organization and interactivity. Described in detail, lessons are divided into three phases. First phase is combining presentation factors for affective effects, second is delivering message of various knowledges and third is forming simple interaction.

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The Estimation of Temporal Change Patterns associated with Economic Growth and Urban Areas in a Border Region using DMSP-OLS Nighttime Imagery Data: The Case Study of Jilin Province, China (DMSP-OLS 야간영상자료를 이용한 접경지역의 경제성장과 시가지 면적의 시계열 변화 패턴 추정: 중국 지린성을 사례로)

  • Kim, Minho;Joh, Young-Kug
    • Journal of the Economic Geographical Society of Korea
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    • v.22 no.4
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    • pp.458-471
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    • 2019
  • DMSP-OLS nighttime satellite imagery could be used to derive the sum of lights (SOL) and built-up area, and the two indices have been widely employed to make the estimation of socio-economic variables and the dynamics of urban developments. Considering it, this research investigated the spatiotemporal patterns of economic growth and urbanized area in Jilin Province, China, using DMSP-OLS data for a time span between 1992 and 2012. This study found the SOLs of both the province and most cities to tend to grow during the period. While SOL-weighted centroids' means moved towards northwestern direction, urban-area centroids' means followed the trend of south-eastern migration. These directional patterns could be associated with the Northeast Revitalization Plan of Chinese governments. Nonetheless, a future study will need to consider SNPP VIIRS DNB imagery in order to overcome temporal limitation of DMSP-OLS data. In addition, it is also necessary to estimate socio-economic indices, e.g., growth regional domestic product, using a regression model developed with correlation relationship between economic statistics ad SOL.