• 제목/요약/키워드: local field

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유한요소법을 이용한 쌍극자 공간전하 방전분산형 피뢰침 정전유도구체의 국부전계 해석 (Local Electric Field Analysis for Evaluation of Charge Transfer System Using Sequential Sub-window Techniq)

  • 정용기;곽희로;이준호;박일한
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1650-1652
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    • 2003
  • In this study, in order to increase electric field intensify near a lightning rod a floating conductor is adopted. If a floating conductor is located near the lightning rod, the positive and negative charges are equally induced on the lightning rod and the floating conductor, and the local electric field intensity near them increases. This increase of electric field intensity can ignite easily the ionization process of the surrounding air and the corona phenomenon begins there. It occurs before the usual lightning process begins on the top of the conventional rod. The charges of the ground or some buildings are omitted during the corona process through the floating conductor. Therefore, the probability of the main lightning on the conventional rod can be reduced.

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Where Some Inert Minimal Ring Extensions of a Commutative Ring Come from

  • Dobbs, David Earl
    • Kyungpook Mathematical Journal
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    • 제60권1호
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    • pp.53-69
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    • 2020
  • Let (A, M) ⊂ (B, N) be commutative quasi-local rings. We consider the property that there exists a ring D such that A ⊆ D ⊂ B and the extension D ⊂ B is inert. Examples show that the number of such D may be any non-negative integer or infinite. The existence of such D does not imply M ⊆ N. Suppose henceforth that M ⊆ N. If the field extension A/M ⊆ B/N is algebraic, the existence of such D does not imply that B is integral over A (except when B has Krull dimension 0). If A/M ⊆ B/N is a minimal field extension, there exists a unique such D, necessarily given by D = A + N (but it need not be the case that N = MB). The converse fails, even if M = N and B/M is a finite field.

Local Self-Government in the Conditions of Digitization: International-Legal Experience

  • Perezhniak, Boris;Vasylchuk, Larysa;Bevz, Tetiana;Pyroha, Serhii;Ulianov, Oleksiy
    • International Journal of Computer Science & Network Security
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    • 제22권10호
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    • pp.165-170
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    • 2022
  • Nowadays more and more attention is paid to digital technologies, digitization, and the digitization of public services in particular. Progressive countries aim to build "digital" governance and a digital economy. In this aspect, the international experience of using digitization in the field of public administration, including in local self-government bodies, plays an important role. Therefore, it is important to analyze the international legal experience of the functioning of local self-government in the conditions of digitization. The purpose of the work is to study the international legal experience of the functioning of local self-government in the conditions of digitization. The object of the study is local self-government in the conditions of digitization through the prism of international legal experience. The subject of the study is social relations that arise, change, and cease during the implementation of digitization in local self-government in Ukraine and foreign countries. The research methodology consists of such methods as the method of philosophical hermeneutics; dialectical method; classification method; comparative method; target method; method of documentary analysis; generalization method. Research results. As a result of the conducted research, the international experience of the functioning of local self-government in conditions of digitization was analyzed. In particular, the impact of digitization processes on the course of the decentralization reform in Ukraine is summarized. Also, from the analysis of international experience, a conclusion was made about the potential possibility of reducing the existing gap in the process of communication between the central government and united territorial communities thanks to the introduction of the latest technologies in the field of administrative services, to stimulate innovative and economic development of regions, attracting the attention of businesses and potential investors, as well as the functioning of more open local authorities with electronic communication tools.

A Modeling Study of Local Equivalence Ratio Fluctuation in Imperfectly Premixed Turbulent Flames

  • Moon, Hee-Jang
    • Journal of Mechanical Science and Technology
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    • 제18권8호
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    • pp.1479-1489
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    • 2004
  • The effect of fluctuation of Equivalence Ratio (ER) in a turbulent reactive field has been studied in order to check the global combustion characteristics induced by the local fluctuation. When the flow is premixed on a large scale, closer examination on a small scale reveals that local fluctuations of ER exist in an imperfectly premixed mixture, and that these fluctuations must be considered to correctly estimate the mean reaction rate. The fluctuation effect is analyzed with DNS by considering the joint PDF of reactive scalar and ER, followed by modeling study where an extension of stochastic mixing models accounting for the ER fluctuation is reviewed and tested. It was found that models prediction capability as well as its potential is in favor to this case accounting the local ER fluctuation. However, the effect of local fluctuation did not show any notable changes on the mean global characteristics of combustion when statistical independence between the reactive scalar and ER field is imposed, though it greatly influenced the joint PDF distribution. The importance of taking into account the statistical dependency between ER and combustible at the initial phase is demonstrated by testing the modeled reaction rate.

Development of Potential Function Based Path Planning Algorithm for Mobile Robot

  • Lee, Sang-Il;Kim, Myun-Hee;Oh, Kwang-Seuk;Lee, Sang-Ryong
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.2325-2330
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    • 2005
  • A potential field method for solving the problem of path planning based on global and local information for a mobile robot moving among a set of stationary obstacles is described. The concept of various method used path planning is used design a planning strategy. A real human living area is constructed by many moving and imminence obstacles. Home service mobile robot must avoid many obstacles instantly. A path that safe and attraction towards the goal is chosen. The potential function depends on distance from the goal and heuristic function relies on surrounding environments. Three additional combined methods are proposed to apply to human living area, calibration robots position by measured surrounding environment and adapted home service robots. In this work, we proposed the application of various path planning theory to real area, human living. First, we consider potential field method. Potential field method is attractive method, but that method has great problem called local minimum. So we proposed intermediate point in real area. Intermediate point was set in doorframe and between walls there is connect other room or other area. Intermediate point is very efficiency in computing path. That point is able to smaller area, area divided by intermediate point line. The important idea is intermediate point is permanent point until destruction house or apartment house. Second step is move robot with sensing on front of mobile robot. With sensing, mobile robot recognize obstacle and judge moving obstacle. If mobile robot is reach the intermediate point, robot sensing the surround of point. Mobile robot has data about intermediate point, so mobile robot is able to calibration robots position and direction. Third, we gave uncertainty to robot and obstacles. Because, mobile robot was motion and sensing ability is not enough to control. Robot and obstacle have uncertainty. So, mobile robot planed safe path planning to collision free. Finally, escape local minimum, that has possibility occur robot do not work. Local minimum problem solved by virtual obstacle method. Next is some supposition in real living area.

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An IoT routing based Local River Field Environment Management solution using Uzbekistan Testbed

  • Khudaybergenov, Timur;Park, Youngki;Im, Sangil;Ho, Bae Jin;Yang, Seungyoun;Kim, Jintae;Lee, Sunghwa;Cha, Dae Yoon;Woo, Deokgun;Cha, Jaesang
    • International journal of advanced smart convergence
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    • 제9권3호
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    • pp.1-8
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    • 2020
  • Water consumption has grown at more than 2.5 times, comparing the past century. About 2.8 billion people live in river basins with some form of water deficit, because more than 75 % of the river flows are withdrawn for agriculture and other needs. Challenges faced by more and more countries in their struggle for economic and social development are increasingly related to water. This paper proposes a test of an effective local river field environment management solution. And describing a part of a pilot project for the ministry of water resources of Uzbekistan. Current work focused on direct action items of the existing project and describe an IoT routing based solution for local river field environment management solutions. Suggested technological decisions provided by needs and on-site testing results. The paper describes the backbone of IoT routing based river water resources management system.

국지기상 모니터링용 필드서버를 위한 플러딩 라우팅 프로토콜의 구현 (Implementation of Flooding Routing Protocol for Field sever using Weather Monitoring System)

  • 유재호;이승철;정완영
    • 한국정보통신학회논문지
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    • 제15권1호
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    • pp.233-240
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    • 2011
  • 산악지역이나 어떤 한정된 지역에서 급작하게 나타나는 기상변화를 모니터링하기 위해 유비쿼터스 센서 네트워크 기술을 이용한 필드서버를 개발하였다. 국지적 기상변화에 의한 인명 및 재난 피해를 최소화하기 위해 국지역내에 배치된 필드서버간의 데이터 전달이 매우 중요한 기술이다. 일정한 국지적 지역에 배치 된 필드서버들로부터 일정한 시간 간격으로 수집되는 온도, 습도, 조도, 기압, 이슬점, 수위의 기상데이터를 전송하기 위한 플러딩 라우팅 프로토콜 전송방식을 구현하였으며, 이를 제작 된 외부센서모듈과 Telosb 계열의 센서노드에 nesC 언어를 사용한 초소형 무선센서네트워크 플랫폼인 TinyOS로 프로그램 하여서 서버 컴퓨터에서 모니터링 할 수 있도록 하였다.

국지기상 모니터링을 위한 WSN 기반 필드서버 제작 (Design of WSN based Field Server for Local Weather Monitoring)

  • 안성모;김재경;유재호;정상중;정완영
    • 한국정보통신학회논문지
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    • 제15권2호
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    • pp.493-500
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    • 2011
  • 최근 갑작스러운 국지성 기후변화나 기상악화로 인해 다양한 자연재해가 빈번히 발생하고 있으며 이러한 재해로 인한 인명피해 및 재난피해의 규모가 크게 증가하고 있다. 국지적지역에서의 돌발적인 기후변화를 예측하는 것은 기존의 광역 기상예보시스템에 의해서는 어려움과 한계가 있다. 최근에는 소규모 센서네트워크를 활용한 국지적 기상 모니터링에 관한 방법들이 활발히 연구되고 있다. 본 논문에서는 IEEE 802.15.4 기반의 신뢰성 있는 기상데이터의 계측과 모니터링을 위한 기상 필드서버를 설계 및 제작하였다. 제안된 기상 필드서버는 무선통신을 담당하는 센서노드와 온도, 습도, 조도, 이슬점, 기압, 수위 등의 기상정보를 수집하는 기상센서보드로 구성되며, 이를 통합한 필드서버를 구축하여 국지적 기상변화에 신속하게 대처할 수 있도록 하였다. 서버 PC에서는 각각의 기상관련 정보를 모니터링 및 분석하기 위한 프로그램을 구축하여 국지적 지형이나 지역에서 갑작스러운 기후변화를 감지하고 경고 메시지를 제공하여 국지성 재해로부터 피해를 예방하고자 하였다.

수자원 개발사업 주민의견 유형분석을 통한 환경영향평가 개선방안 (Reformation Methods of Environmental Impact Assessment in Water Resources Development Project by Examining Local Resident Opinions)

  • 양기현;박재충;류영한;정용문;송상진;신재기
    • 환경영향평가
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    • 제20권3호
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    • pp.397-409
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    • 2011
  • This study was carried out for improving the effectiveness of water resources development project through local resident opinions in the environmental impact assessment(EIA). The EIA reports of seven dams were examined. Four dams -Youngju Dam, Seongduck Dam, Buhang Dam and Hantangang Dam- which included many local opinions including 470 opinions of 341 local residents were selected to be analyzed. Local residents submitted their opinions in the six fields which are meteorological phenomena, water quality, land use, fauna and flora, noise and vibration, and residence, and the major opinions of those opinions came from the atmosphere environment field which is 32% of total opinions and social and economic field which is 38% of total opinions, respectively. In submerged area, opinions of the measure for migration and compensation were 91% and in non-submerged area, opinions of the measure for meteorological phenomena was 86%. Those percentages were maximum in each area. Opinions concerned meteorological phenomena were 86% and 53% in Youngju Dam and Seongduck Dam where area is surrounded by existing dam, but there was only 9% and 0% of opinions in Buhang Dam and Hantangang Dam where area is without existing dam nearby. The reformation methods which reflected the resident's opinions were suggested on EIA in dam development projects. First of all, reliability and objectivity of the field of meteorological phenoma should be enhanced by scientific prediction of the phenomenon days. Secondly, techniques reducing uncertainty of various water quality prediction models ought to be developed and effectiveness of the reduction strategies in environmental impact should be quantified. Finally, the draft of EIA report should involve the detailed plans of migration and compensation's procedures, criteria and measures to support.

바람장의 공간적.시간적 해상도가 누출물질 확산에 미치는 영향 (Effects of Spatio-Temporal Resolution of Diagnostic Wind Field on the Dispersion of Released Substance)

  • 김영성
    • 한국대기환경학회지
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    • 제16권4호
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    • pp.327-338
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    • 2000
  • complexity in atmospheric environment coupled with shoreline and complex terrain often causes local variations of meteorology that are distinct from those representative over larger surrounding area, These kinds of local variations are less significant in usual long-term environmental impact analyses dealing with continuous plume. The variations could however be crucial in predicting dispersion of toxic substance released in a relatively small area for a short duration. In the present paper the effects of spatial and temporal resolution of diagnostic wind field on the dispersion of the released substance are investigated by using a puff model. A hypothetical release scenario assumes that a substance is released from a location in the Yochon Industrial Estate and passively dispersed within a few-kilometer distance for an hour. The results show that diagnostic analysis could resolve more spatial variations to some extent by employing smaller grid size. The peak concentrations and puff trajectories obtained from spatially -and/or tmeporally -varing diagnostic wind field are found appreciably different from those obtained from uniform wind field. Attention to high-resolution wind field in the both spatial and temporal spaces is called in the consequence analysis of toxic substance release.

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