• 제목/요약/키워드: Community Energy

검색결과 1,034건 처리시간 0.03초

Evidence for the Luminosity Evolution of Type Ia Supernovae from the Ages of Early-type Host Galaxies

  • Lee, Young-Wook;Kang, Yijung;Kim, Young-Lo;Lim, Dongwook;Chung, Chul
    • 천문학회보
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    • 제38권2호
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    • pp.56.1-56.1
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    • 2013
  • Supernovae type Ia (SNe Ia) cosmology is providing the only direct evidence for the presence of dark energy. This result is based on the assumption that the look-back time evolution of SNe Ia luminosity, after light-curve shape correction, would be negligible. However, the most recent compilation of SNe Ia data shows systematic difference in the Hubble residual (HR) between the E and Sd/Irr galaxies, indicating that the light-curve fitters used by the SNe Ia community cannot quite correct for a large portion of the population age effect. In order to investigate this possibility more directly, we have obtained low-resolution spectra for 30 nearby early-type host galaxies. This data set is used to estimate the luminosity-weighted mean ages and metallicities of host galaxies by employing the population synthesis models. We found an interesting trend between the host galaxy age and HR, in the sense that younger galaxies have positive residuals (i.e., light-curve corrected SNe Ia luminosity is fainter). This result is rather independent of the choice of the population synthesis models employed. Taken at face value, this age (evolution) effect can mimic a large fraction of the HR used in the discovery of the dark energy. This result is significant at 1.4 - 3 sigma levels, depending on the light curve fitters adopted, and further observations and analyses are certainly required to confirm the trend reported here.

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GCAM을 이용한 국내 수송부문 모델링 (Modeling Domestic Transportation Sector Using Global Change Assessment Model)

  • 전승호;김수덕
    • 대한교통학회지
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    • 제35권2호
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    • pp.91-104
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    • 2017
  • 본 연구에서는 통합모형인 GCAM을 활용한 국내수송부문을 모델링에 대해 논의한다. GCAM은 IPCC 5차 보고서 평가에도 활용된, 국제적으로 널리 쓰이는 모형이다. 그럼에도 불구하고 이를 국내수송부문에 그대로 적용하는 데 상당한 문제가 있다. 첫째, GCAM의 기준년도(2010년) 수송 서비스수요가 국가통계와 일치하지 않다는 점. 둘째, 수송부문 시뮬레이션 결과가 관련 부문별 서비스수요의 과거추이를 제대로 반영하고 못하고 있다는 점이다. GCAM을 활용한 국내 수송부문 모델링에서 가장 중요하게 영향을 미치는 수송서비스수요 항등식을 상세히 점검함으로써, 기준년도의 서비스수요를 국가통계와 일치시키도록 노력하였다. 또 GCAM의 시뮬레이션 결과가 과거 통계추이를 제대로 반영할 수 있도록 기존모형을 점검, 수정하였다. 점검 및 수정결과, 기존 GCAM의 시뮬레이션 결과와 어떤 부분에서 문제가 있는지, 또 수송부문별 과거 서비스 수요의 추이가 어떻게 제대로 반영되고 있는지를 상세히 보고하였다. 본 연구는 향후 수송부문의 정책, 기술평가 및 온실가스저감 대책 마련 등을 위한 시나리오 분석의 기본분석도구로 유용하게 쓰일 수 있을 것으로 보인다.

주거환경개선을 위한 농촌주택 리모델링 성능평가지표 설정에 관한 연구 (The Set of Performance Evaluation Index of Remodeling in Rural Housing for Residential Environments Improvement)

  • 김혜란;임창수;김은자;홍광우;문호경
    • 농촌계획
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    • 제20권1호
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    • pp.1-12
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    • 2014
  • Living environments in rural area have become deteriorated rapidly. Increase of aging population, decline in agricultural income, polarization of wealth in rural community due to rural returners have caused severe decline and imbalance of living environments in rural area. Responding to this circumstances, governments currently develop projects for improving living environments focusing on individual housing which were excluded from governmental supports because those had been regarded as private property. Nevertheless, there are still some gaps and problems in evaluating the quality of living environment and suggesting effective solutions. It would be because standards and guidelines of the projects have been based on urban housing system. In order to support the implementation of the projects, this research has developed an index for evaluating and monitoring the quality of living environments in rural area. By applying Delphi method, the index has been created in four categories of 'security', 'convenience', 'comfortability', and 'durability' 'Security' consists of structural safety, crime, disaster, accident prevention. 'Convenience' includes three divisions of living, traffic, farm working. 'Comfortability' is divided into sanitation, indoor environments, and aesthetic appreciation. Lastly, 'durability' has four divisions of energy conservation, environmental friendliness, efficiency, and economics. Each sub-division also has different items from three to twelves. In the case of an index for performance evaluation, items have been derived from energy conservation(6-items), and environmental friendliness(7-items). Items developed as an index for evaluating rural living environments in this research might be good background information for remodeling project in rural housing development.

Change of Sludge Consortium in Response to Sequential Adaptation to Benzene, Toluene, and o-Xylene

  • Park, Jae-Yeon;Sang, Byoung-In
    • Journal of Microbiology and Biotechnology
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    • 제17권11호
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    • pp.1772-1781
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    • 2007
  • Activated sludge was sequentially adapted to benzene, toluene, and o-xylene (BTX) to study the effects on the change of microbial community. Sludge adapted to BTX separately degraded each by various rates in the following order; toluene>o-xylene>benzene. Degradation rates were increased after exposure to repeated spikes of substrates. Eleven different kinds of sludge were prepared by the combination of BTX sequential adaptations. Clustering analyses (Jaccard, Dice, Pearson, and cosine product coefficient and dimensional analysis of MDS and PCA for DGGE patterns) revealed that acclimated sludge had different features from nonacclimated sludge and could be grouped together according to their prior treatment. Benzene- and xylene-adapted sludge communities showed similar profiles. The sludge profile was affected from the point of the final adaptation substrate regardless of the adaptation sequence followed. In the sludge adapted to 50 ppm toluene, Nitrosomonas sp. and bacterium were dominant, but these bands were not dominant in benzene and benzene after toluene adaptations. Instead, Flexibacter sp. was dominant in these cultures. Dechloromonas sp. was dominant in the culture adapted to 50 ppm benzene. Thauera sp. was the main band in the sludge adapted to 50 ppm xylene, but became vaguer as the xylene concentration was increased. Rather, Flexibacter sp. dominated in the sludge adapted to 100 ppm xylene, although not in the culture adapted to 250 ppm xylene. Two bacterial species dominated in the sludge adapted to 250 ppm xylene, and they also existed in the sludge adapted to 250 ppm xylene after toluene and benzene.

Correlation of Cancer Incidence with Diet, Smoking and Socio-Economic Position Across 22 Districts of Tehran in 2008

  • Rohani-Rasaf, Marzieh;Abdollahi, Morteza;Jazayeri, Shima;Kalantari, Naser;Asadi-Lari, Mohsen
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권3호
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    • pp.1669-1676
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    • 2013
  • Background: Variation in cancer incidence in geographical locations is due to different lifestyles and risk factors. Diet and socio-economic position (SEP) have been identified as important for the etiology of cancer but patterns are changing and inconsistent. The aim of this study was to investigate correlations of the incidence of common cancers with food groups, total energy, smoking, and SEP. Materials and Methods: In an ecological study, disaggregated cancer data through the National Cancer Registry in Iran (2008) and dietary intake, smoking habits and SEP obtained through a population based survey within the Urban Health Equity Assessment (Urban-HEART) project were correlated across 22 districts of Tehran. Results: Consumption of fruit, meat and dairy products adjusted for energy were positively correlated with bladder, colorectal, prostate and breast and total cancers in men and women, while these cancers were adversely correlated with bread and fat intake. Also prostate, breast, colorectal, bladder and ovarian cancers had a positive correlation with SEP; there was no correlation between SEP and skin cancer in both genders and stomach cancer in men. Conclusions: The incidence of cancer was higher in some regions of Tehran which appeared to be mainly determined by SEP rather than dietary intake. Further individual data are required to investigate reasons of cancer clustering.

연근해 생물 잠재생산력 추정을 위한 Herbivores 단계의 에너지 전환 효율의 추정 방법에 관한 고찰 (Review of Methods for Measurement of Ecological Energy Conversion Rate by Herbivores in Offshore and Adjacent Sea)

  • 김용술
    • 한국수산과학회지
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    • 제24권4호
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    • pp.266-271
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    • 1991
  • 연근해 생물생산의 가시적 주체가 되는 초식어류의 잠재생산력을 연역적방법으로 추정하려 할 때, 기초생산력으로부터의 에너지 전환효율의 추정이 중심과제가 된다. 이 과제에 관련한 지금까지의 연구성과 중에서 아직 그 방법에 정론이 없는, 이른바 해수중의 '먹이감'에서 herbivores 소화관내의 '먹은 것'으로의 변환효율$(K_i)$에 관한 부분을 고찰하였다. 해수 중 먹이생물의 종별조성 r과 herbivores 소화관내의 종별조성 p를 사용하는 Ivlev와 Sorygin의 계수들이$(K_i)$로 사용되기에는 부적당함을 지적하면서, 그대신 유사도 지수의 하나인 CCOS를 $(K_i)$로 가공하여 사용할 수 있는 가능성을 제시한다.

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Advanced Forecasting Approach to Improve Uncertainty of Solar Irradiance Associated with Aerosol Direct Effects

  • Kim, Dong Hyeok;Yoo, Jung Woo;Lee, Hwa Woon;Park, Soon Young;Kim, Hyun Goo
    • 한국환경과학회지
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    • 제26권10호
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    • pp.1167-1180
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    • 2017
  • Numerical Weather Prediction (NWP) models such as the Weather Research and Forecasting (WRF) model are essential for forecasting one-day-ahead solar irradiance. In order to evaluate the performance of the WRF in forecasting solar irradiance over the Korean Peninsula, we compared WRF prediction data from 2008 to 2010 corresponding to weather observation data (OBS) from the Korean Meteorological Administration (KMA). The WRF model showed poor performance at polluted regions such as Seoul and Suwon where the relative Root Mean Square Error (rRMSE) is over 30%. Predictions by the WRF model alone had a large amount of potential error because of the lack of actual aerosol radiative feedbacks. For the purpose of reducing this error induced by atmospheric particles, i.e., aerosols, the WRF model was coupled with the Community Multiscale Air Quality (CMAQ) model. The coupled system makes it possible to estimate the radiative feedbacks of aerosols on the solar irradiance. As a result, the solar irradiance estimated by the coupled system showed a strong dependence on both the aerosol spatial distributions and the associated optical properties. In the NF (No Feedback) case, which refers to the WRF-only stimulated system without aerosol feedbacks, the GHI was overestimated by $50-200W\;m^{-2}$ compared with OBS derived values at each site. In the YF (Yes Feedback) case, in contrast, which refers to the WRF-CMAQ two-way coupled system, the rRMSE was significantly improved by 3.1-3.7% at Suwon and Seoul where the Particulate Matter (PM) concentrations, specifically, those related to the $PM_{10}$ size fraction, were over $100{\mu}g\;m^{-3}$. Thus, the coupled system showed promise for acquiring more accurate solar irradiance forecasts.

통합학문 5대 법칙의 제안 (Suggestion of the Five Laws for Integral Studies)

  • 김덕진
    • 플랜트 저널
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    • 제14권1호
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    • pp.34-41
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    • 2018
  • 과거의 학문은 기초의 시대이며, 현재의 학문은 융합의 시대이며, 미래의 학문은 통합의 시대이다. 학문 통합의 필수 조건은 모든 학문이 서로 동등해야 한다는 것이며, 오직 자연법칙으로부터 파생된 법칙만이 통합의 동등성을 구현할 수 있을 것이다. 변화를 일으킬 수 있는 능력을 에너지로 정의할 것을 제안한다. 만물은 변화하며 그 변화에는 방향성이 필히 존재하므로, 변화와 방향성은 모든 학문에 동등하게 적용된다. 통합학문의 제 0 법칙은 존재의 법칙, 제 1 법칙은 변화 보존의 법칙, 제 2 법칙은 무효변화 증가의 법칙, 제 3 법칙은 지침의 법칙, 그리고 제 4 법칙은 융합의 법칙이다. 위 법칙들은 열역학의 자연법칙과 매우 유사함을 볼 수 있다. 통합학문 5 대 법칙의 최종 목표는 지구상에서 자연, 인간, 인공지능 개체들이 서로 협력하여 발전하는 공동체의 구현이다.

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독일 공동주택 놀이터의 친환경적 특성 연구 (A Study on the Eco-friendly Properties of Apartment Housing Playground in Germany)

  • 김자경
    • 한국실내디자인학회논문집
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    • 제24권5호
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    • pp.87-98
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    • 2015
  • As an apartment house as well as improving quality of life is becoming one of the brands, it is increasing the importance of the outer space with the facilities in the housing complex. In particular, the outdoor playground such as the community facilities that children and adults share as the activity areas for residents has received attention. However, actually children have not used many of Korean apartment housing playgrounds that were installed formally in the scrap area according to the housing plan by residential construction standards. it is considered necessary to improve the quality of the playground in housing complex and reform it in order to make the eco-friendly play space in which children can play safely and h healthily. As an alternative, we analyzed the eco-friendly properties of the playgrounds installed in the eco-friendly housing complex in Germany and derived the main planning elements of eco-friendly playground. In the observational survey of the 10 playgrounds in 9 housing complexes in 5 regions in Germany, we evaluated the environment-friendliness of these playgrounds in the 8 fields(location and placement, ecological environment, play space, play equipment and facilities, additional facilities, materials and resources, energy saving, environmental load reduction) according to the levels(suitable, partial reflection, unsuitable, non-reflection) of reflection of eco-friendly planning factors. The following is the summary of the results about the reflection of eco-friendly planning factors. In terms of "suitable": location and placement(88.8%), play equipment and facilities(73.5%), additional facilities(60.6%), environmental load reduction(54%), and ecological environment(50%) were higher than others. In terms of "unsuitable": there was nothing. In terms of "non-reflection": energy saving(95%), additional facilities(32.2%), and materials and resources(30.9%) were in order. Therefore, on the basis of these results, this study proposed the planning indicators to be considered first and the planning factors that should be complemented and improved in the construction of apartment housing playground in future.

시스템 다이내믹스 모델링을 통한 중.저준위방사성폐기물시설 부지선정 영향 인자 분석 (Logical Analysis for Parameters of Radioactive waste Policy using System Dynamics Technique)

  • 이영준;조성경
    • 에너지공학
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    • 제17권2호
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    • pp.77-87
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    • 2008
  • 2005년 중 저준위 방사성폐기물처분시설의 부지선정 과정은 목표를 달성했다는 측면에서 성공 사례로 평가할 수 있다. 그러나 과정에서 나타난 한계점들은 여전히 풀어야 할 숙제로 남아 있다. 이 정책의 성공과 한계에 대한 영향 인자와 이들 상호간의 관계를 분석함으로써 향후 관련 정책 수립 및 추진에 효과적인 틀을 제공할 수 있을 것으로 예상된다. 방사성폐기물처분시설 정책의 정성적인 요인들은 변수로 설정하여 방사성폐기물처분시설 모델을 수립하였으며 이 모델을 계산하기 위하여 통합적 분석 툴인 시스템다이내믹스를 활용하였다. 시스템다이내믹스 분석 결과를 보면 정책주체의 투명성, 지역 지원 수준, 홍보를 조절 가능한 요인으로 설정하였을 때, 찬성 논리와 반대 논리 사이에 직간접적으로 영향을 미치고 중간에 신뢰가 매우 중요한 역할을 하고 있음을 가시적으로 나타낼 수 있었다. 신뢰는 제시된 여러 인자들에 영향을 미치거나 피드백되어 의견이 결정의 방향성을 전환할 있는 정책지렛대라 할 수 있다.