• 제목/요약/키워드: Balanced-Unbalanced

검색결과 309건 처리시간 0.021초

남북통일과 지역균형개발정책 (Korea Reunification and Factor Movement : The Policy for Interregional Balanced Economic Growth)

  • 김홍배;임재영
    • 지역연구
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    • 제14권1호
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    • pp.47-64
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    • 1998
  • This paper attempts to forecast regional economic changes and to analyze government polices for interregional balanced economic growth in case of Korea Reunification. It begins with be reunified at the year 2010. The model is largely neoclassical. Since the future of North Korea is unclear, two possible scenarios are presented. The paper projects economic growth of regions, specifically forecasting growth of regions, specifically forecasting GRDP, the number of migrants and the quantity of moving capital. The results obtained show that spatially unbalanced economic growth will take place in the reunified Korea through factor movement. Two polices including public capital provision policy and income subsidy policy are thus suggested and analyed.

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Simplified elastic design checks for torsionally balanced and unbalanced low-medium rise buildings in lower seismicity regions

  • Lam, Nelson T.K.;Wilson, John L.;Lumantarna, Elisa
    • Earthquakes and Structures
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    • 제11권5호
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    • pp.741-777
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    • 2016
  • A simplified approach of assessing torsionally balanced (TB) and torsionally unbalanced (TU) low-medium rise buildings of up to 30 m in height is presented in this paper for regions of low-to-moderate seismicity. The Generalised Force Method of Analysis for TB buildings which is illustrated in the early part of the paper involves calculation of the deflection profile of the building in a 2D analysis in order that a capacity diagram can be constructed to intercept with the acceleration-displacement response spectrum diagram representing seismic actions. This approach of calculation on the planar model of a building which involves applying lateral forces to the building (waiving away the need of a dynamic analysis and yet obtaining similar results) has been adapted for determining the deflection behaviour of a TU building in the later part of the paper. Another key original contribution to knowledge is taking into account the strong dependence of the torsional response behaviour of the building on the periodic properties of the applied excitations in relation to the natural periods of vibration of the building. Many of the trends presented are not reflected in provisions of major codes of practices for the seismic design of buildings. The deflection behaviour of the building in response to displacement controlled (DC) excitations is in stark contrast to behaviour in acceleration controlled (AC), or velocity controlled (VC), conditions, and is much easier to generalise. Although DC conditions are rare with buildings not exceeding 30 m in height displacement estimates based on such conditions can be taken as upper bound estimates in order that a conservative prediction of the displacement profile at the edge of a TU building can be obtained conveniently by the use of a constant amplification factor to scale results from planar analysis.

해상풍력단지에서의 PMSG 풍력발전기를 활용한 계통연계점 불평형 전원 보상 (Compensation of Unbalanced PCC Voltage in an Off-shore Wind Farm of PMSG Type Turbines)

  • 강자윤;한대수;서용석;정병창;김정중;박종형;최영준
    • 전력전자학회논문지
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    • 제20권1호
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    • pp.1-10
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    • 2015
  • This paper proposes a control algorithm for permanent magnet synchronous generators with a back-to-back three-level neutral-point clamped voltage source converter in a medium-voltage off-shore wind power system under unbalanced grid conditions. Specifically, the proposed control algorithm compensates for unbalanced grid voltage at the PCC (Point of Common Coupling) in a collector bus of an off-shore wind power system. This control algorithm has been formulated based on symmetrical components in positive and negative synchronous rotating reference frames under generalized unbalanced operating conditions. Instantaneous active and reactive power is described in terms of symmetrical components of measured grid input voltages and currents. Negative sequential component of AC input current is injected into the PCC in the proposed control strategy. The amplitude of negative sequential component is calculated to minimize the negative sequential component of grid voltage under the limitation of current capability in a voltage source converter. The proposed control algorithm enables the provision of balanced voltage at the PCC resulting in the high quality generated power from off-shore wind power systems under unbalanced network conditions.

3상 불평형 전원 시스템의 새로운 위상각 검출기법을 이용한 순간전압보상기의 해석 및 제어 (Analysis and Control of Instantaneous Voltage Compensator Using New Phase Angle Detection Method Synchronized by Positive Sequence of Unbalanced 3-Phase Source)

  • 이승요;고재석;목형수;최규하
    • 전력전자학회논문지
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    • 제4권3호
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    • pp.275-284
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    • 1999
  • 3산 전력 시스템에서 불평형 전원의 전압은 대칭좌표법에 의하여 정상, 역상, 영상성분으로 각각 분해 될 수 있고 또한 전력 시스템에 중성선이 없는 경우 영상성분은 부하측에 나타나지 않게 된다. 따라서 중성선이 없는 불평형 시스템에서는 전원측의 역상성분만을 검출하여 보상함으로써 부하측에 평형된 전압을 공급할 수 있을 뿐만 아니라 정상성분의 크기를 제어함으로써 부하에 인가되는 전압의 크기를 조정하는 것이 가능하다. 아울러 이러한 불평형 전압에 의한 각 대칭분은 3상 2상 변환을 통한 동기좌표축상에서의 효율적인 검출이 가능한데, 본 논문에서는 전원의 불평형 성분을 동기좌표축 상에서 순시적으로 검출하여 이를 보상하고 부하의 전압조정 기능 역시 수행하는 순간전압보상기의 보상 알고리즘 및 이때 좌표변환시 필요한 전원의 위상각 정보를 전원의 정상성분에 일치시키는 새로운 위상각 검출 알고리즘을 제안한다. 제안된 보상 시스템의 성능 및 특성을 시뮬레이션을 통하여 해석하고 실험으로써 검증하였다.

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학교급식 음식물쓰레기에 대한 인식 및 잔반율 영향 요인 분석 - 경남지역 초등학교를 중심으로 - (Elementary School Students' Perception of Food Waste and Factors Affecting Plate Waste Rate of School Foodservice in the Gyeongnam Area)

  • 윤선재;김현아
    • 대한영양사협회학술지
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    • 제18권2호
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    • pp.126-140
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    • 2012
  • The purpose of this study was to investigate elementary school students' perception of food waste as well as to identify factors affecting the plate waste rate of school foodservice in the Gyeongnam area. Questionnaires were distributed to 280 students from June 20 to July 5, 2011 and a total of 279 were analyzed. The results of this study were as follows. First, the main reason of plate waste was 'big portion size', which suggests that portion size should be adjusted. Second, the attitude for food waste reduction was 3.67 based on a 5-point Likert scale (1: strongly disagree, 5: strongly agree). Third, the average plate waste rate of school foodservice was 18.65%. Fourth, there were four factors affecting plate waste rate; balanced/unbalanced diet, satisfaction of school foodservice, need for nutrition education related to food waste, and attitude towards food waste reduction. The plate waste rates of the students who ate a balanced diet were significantly lower than those of the students who ate an unbalanced diet (P<0.001). The plate waste rates of the students who were satisfied with school foodservice were significantly lower than those of the students who were unsatisfied (P<0.001). The plate waste rates of the students who recognized the need for nutrition education were significantly lower that those of the students who did not recognize this (P<0.01). Finally, the students' attitudes towards food waste reduction were significantly negatively correlated with plate waste rate (P<0.01). In conclusion, in order to successfully reduce plate waste in school foodservice, nutrition education should be provided on proper portion size, balanced diet, and food waste. Further, introduction of partial self-service by school foodservice should be reviewed, and strategies for the improvement of school foodservice satisfaction should be applied.

국가발전과 지역균형발전에 관한 연구 - 경제성장과 지역균형발전의 상관관계를 중심으로 - (A Study on National Development & Balanced Development by Region - Mainly Interrelation between Economic growth and Balanced Regional Development -)

  • 김남일
    • 한국컴퓨터정보학회논문지
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    • 제10권2호
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    • pp.205-213
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    • 2005
  • 지역균형발전이란 지역간 경제적 생산성 및 소득의 격차를 줄이고 국민들이 어느 지역에서나 비슷한 수준의 소득으로 비슷한 생활수준을 누릴 수 있게 한다는 점에서 경제적, 사회적으로 큰 의미를 가진다 그러나 우리나라는 지난 30여년동안 고도경제성장 위주의 국가경제 정책과 정치, 사회의 구조적 요인으로 인하여 서울을 중심으로 한 수도권 지역으로의 경제력 및 개발이 편중되면서 지역간 불균형 성장이 야기되어 국가발전에 커다란 장애요인으로 대두되었다 특히 지역간 불균형성장은 국민경제의 효율적인 자원배분을 왜곡시키고 특정지역주민들의 소외의식을 야기하였으며 이로 인해 사회적, 정치적 문제로 항상 비화되어 국민통합을 저해하는 사회적 갈등을 심화 시켰다 따라서 본 연구의 주된 내용은 국가발전의 개념을 구성하는 경제성장과 지역균형발전 관계를 규명하는데 있으며, 연구를 구체화하기 위한 분석의 대상을 경제성장과 지역간 인구 및 생활 편의시설의 변화 추이를 통한 지역간 인구격차 분석과 지역간 생활편익시설의 격차 등을 분석대상으로 삼았다. 분석을 위한 공간적 범위는 대한민국 국토 전역을 대상으로 삼았으며. 연구의 시간적 범위는 경제개발 5개년 계획을 추진하였던 1962년부터 지역균형개발을 실시하였던 2001년까지 10년 단위를 설정하였다.

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Droop Control을 이용한 3상 4선식 UPS의 병렬운전 (Parallel Operation of Three-Phase Four wire UPS using Droop Control)

  • 김현섭;한정호;송중호
    • 조명전기설비학회논문지
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    • 제27권4호
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    • pp.88-95
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    • 2013
  • A new droop control method which can be applied to 3-phase 4-wire uninterruptible power supply is proposed in this paper. The droop control method for parallel operation is very attractive one as UPS parallel operation can be carried out without any data communication devices provided among UPS systems connected, but it reportedly shows a PnP(plug-and-play) problem. A basic reason why a circulating current could flow among parallel-connected UPS systems is clearly investigated as well when droop-controlled-ups systems are operated in the manner of PnP. The proposed algorithm is deduced from the investigated result and is basically structured to keep a balanced frequency and balanced voltage profile against power variation. This paper shows that balanced parallel operation of droop control method can be obtained under unbalanced load as well as balanced load conditions when PnP operation is needed and load change occurs.

낙후지역 발전을 위한 광역자치단체 특별회계 운영 사례 비교연구 (A Comparative Study on the Case of Wide-area Autonomous Communities's Special Accounts Operation for Distressed Region Development)

  • 이성재;김형오
    • 농촌지도와개발
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    • 제19권3호
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    • pp.649-672
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    • 2012
  • The government established Special Accounts for Balanced National Development in 2005, and the Metropolitan Council has enacted and executed ordinance relevant to special accounts to relieve regional unbalanced growth and to promote regional balanced growth. This study derived a political implication through the comparison analysis of the background of establishment and its purpose, the selection criteria of support target, finance scale and tax revenue finance, appropriation target and finance distribution, etc. on the basis of Chungcheongnam-do Special Accounts for Balanced Development and Jeollabuk-do Eastern part Special Accounts among the special accounts implemented in metropolitan council. The major conclusions of this study are as follows. First, the transition from the concept of balanced development to specialized development is necessary for the development of distressed region. Second, the pure wastefulness ratio of the local government's tax revenue finance of special accounts designed concentrating upon special accounts for Wide-area Autonomous Communities development should be gradually expanded. Third, Special Accounting budget should be supported to promote specialized development through the selection and concentration centering around comparatively advantageous resource within the region. Fourth, the strategic special accounts budget application system of cities and counties to utilize the projects of the government and the province to achieve the goal of cities and counties should be prepared.

농촌기본소득제 도입에 관한 탐색적 연구 (An Exploratory Study on the Introduction of Basic Income Guarantee for Rural Residents)

  • 박경철;한승석
    • 농촌지도와개발
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    • 제28권2호
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    • pp.69-83
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    • 2021
  • Under the premise of unbalanced development between urban and rural areas, this study raised criticism that the balanced national development policies in South Korea, which had been promoted in earnest after 'the Participatory Government' has adversely deepened the development gap between urban and rural areas by promoting the development of urban. In the meantime, the agricultural economy that supported the rural economy has gradually collapsed after reckless market opening, and due to the balanced national development policy focusing on urban infrastructure construction, rural areas are facing a crisis of 'depopulation' and 'regional extinction.' For this reason, many local governments have recently recognized the public values of agriculture and have introduced 'agrarian basic income' for the sustainability of agriculture. However, there is a limit to overcoming the crisis in rural areas because the population of farmers among rural residents is only 25%. Therefore, this study proposes the necessity of introducing the basic income for rural residents as a new paradigm for balanced development between urban and rural areas beyond the existing policy limits, based on surveys of opinions of residents living in Chungchengnam-do, South Korea and experts on the introduction of 'basic income for rural residents' in the future.

불균형 자료에서 AIC를 이용한 선형혼합모형 선택법의 효율에 대한 모의실험 연구 (Simulation Study on Model Selection Based on AIC under Unbalanced Design in Linear Mixed Effect Models)

  • 이용희
    • 응용통계연구
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    • 제23권6호
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    • pp.1169-1178
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    • 2010
  • 본 논문은 불균형 자료에서 선형혼합모형에 적용되는 Akaike Information Criterion(AIC)의 효율에 대한 연구이다. Vaida와 Balanchard (2005)에 의해 제안된 cAIC(conditional AIC)는 mAIC(marginal AIC)가 임의효과의 예측에 대한 불확실성을 모형선택에서 반영하지 못하는 단점을 극복할 수 있는 방법이다. cAIC에 대한 이론적인 성질과 확장은 Liang 등 (2008)과 Greven과 Kneib (2010)에 의하여 연구되었다. cAIC의 형태는 자료의 구조에 영향을 받지는 않지만 선형혼합모형에서 모수의 추정 효율은 자료의 불균형의 정도에 따라 많은 영향을 받는 것이 알려져 있다. 기존의 연구에서 실시한 모든 모의실험이 자료가 균형인 경우에만 실행되어 자료의 불균형이 AIC에 근거한 혼합모형 선택 방법의 효율에 어떤 영향을 미치는지 알려져 있지 않다. 본 논문은 자료의 불균형이 모형선택 방법의 효율에 미치는 영향을 모의실험을 통하여 알아보았다. 자료의 불균형이 심해짐에 따라 AIC에 근거한 모형선택방법은 복잡한 모형을 선택하는 경향이 낮아짐을 보였다.