• 제목/요약/키워드: alternative measures

검색결과 536건 처리시간 0.034초

Quantifying how urban landscape heterogeneity affects land surface temperature at multiple scales

  • Rahimi, Ehsan;Barghjelveh, Shahindokht;Dong, Pinliang
    • Journal of Ecology and Environment
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    • 제45권4호
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    • pp.190-202
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    • 2021
  • Background: Landscape metrics have been widely applied to quantifying the relationship between land surface temperature and urban spatial patterns and have received acceptable verification from landscape ecologists but some studies have shown their inaccurate results. The objective of the study is to compare landscape metrics and texture-based measures as alternative indices in measuring urban heterogeneity effects on LST at multiple scales. Results: The statistical results showed that the correlation between urban landscape heterogeneity and LST increased as the spatial extent (scale) of under-study landscapes increased. Overall, landscape metrics showed that the less fragmented, the more complex, larger, and the higher number of patches, the lower LST. The most significant relationship was seen between edge density (ED) and LST (r = - 0.47) at the sub-region scale. Texture measures showed a stronger relationship (R2 = 34.84% on average) with LST than landscape metrics (R2 = 15.33% on average) at all spatial scales, meaning that these measures had a greater ability to describe landscape heterogeneity than the landscape metrics. Conclusion: This study suggests alternative measures for overcoming landscape metrics shortcomings in estimating the effects of landscape heterogeneity on LST variations and gives land managers and urban planners new insights into urban design.

유입량 모의 기법을 활용한 국내 다목적댐 가뭄 대책의 경제적 효과 평가 (Evaluating the economic benefit of diverse drought mitigation strategies for Korean reservoir systems based on simulated inflow sequences)

  • 지수광;신금채;이승엽;안국현
    • 한국수자원학회논문집
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    • 제56권8호
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    • pp.485-496
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    • 2023
  • 최근 우리나라는 댐 운영에 있어서 다양한 가뭄 대책을 활용하여 가뭄 시 물 부족의 위험 리스크를 줄이기 위해 노력하고 있다. 이를 중심으로 다양한 연구들이 수행되었지만 가뭄 대책의 효과를 경제적인 측면에서 살펴본 연구는 현재 전무한 실정이다. 본 연구에서는 ARIMA와 Copula 기반의 장기간 모의 유입량 생성 모형과 댐별 가뭄 대책을 반영한 댐 운영 모형을 활용하여 전국의 다목적댐을 대상으로 가뭄 대책 시행에 따른 경제적 효과를 평가하였다. 경제적 편익 산정 결과 연계 운영·대체 공급과 비상공급대책의 단위 유량 당 기대 편익이 각각 1,176원과 1,139원으로 가장 높 으며, 비상 용량 활용과 용수공급조정의 편익은 956원과 875원으로 추정된다. 추가로 미래에 가뭄이 심화된다는 가정을 기반으로 가뭄 대책의 경제적 편익의 변화에 대하여 살펴본 결과 유입량 감소로 인한 가뭄 리스크의 변화는 모든 가뭄 대책의 경제적 편익을 높이는 효과를 보였다. 용수공급조정의 경제적 효과는 기존 대비 2.6% 상승하였으나, 연계 운영·대체 공급의 경제적 효과는 기존 대비 11.7% 상승하였다. 이는 가뭄의 위험도가 증가할수록 연계 운영과 대체 공급과 같은 댐 네트워크 기반의 대책이 주요한 것으로 판단된다. 본 연구는 향후 가뭄 대책의 선정과 활용에 있어서 기본자료로 활용될 것으로 기대된다.

이동식 크레인 사망재해의 인지공학적 대안 (Alternative Prevention on Human Error of Fatal Injuries by the Mobile Cranes)

  • 강현수;박범
    • 대한안전경영과학회지
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    • 제17권4호
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    • pp.135-141
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    • 2015
  • According to the statistics, occupational fatal injuries by mobile cranes were about 12 per year in whole industrial. Mobile cranes are widely used in various parts of industries to improve the efficiency of the work. However considerable number of fatal injuries happen each year during the operation of the machines. In this study, the current regulations to be adequate in industrial site have to be renew in order to prevent the fatal injuries by mobile cranes. Fatal injury analyses were conducted with several accident cases by the mobile cranes. For each accident, the causes of the injuries were examined and proper safety measures were proposed. In this study, the mobile crane showed a high fatality rate in industrial accidents and no detailed cause analysis of fatal accidents was conducted in terms of unsafe acts or conditions. This study proposed a revision of the standard guideline as an accident prevention measures through in-depth analysis of fatal accidents. First, among the mainly five machines caused the accidents, mobile crane was higher for the second showed 0.6% for number of fatalities compared to number of mobil cranes and for the third showed 11% for number of fatalities compared to number of injuries. Second, main cause of cognitive engineering agenda was visibility, responsibility, affordance. As the measures to prevent accidents before starting operation, alternative revision for the fool proof including visibility, responsibility, affordance etc. for the fool proof measures was proposed. Third, alternative revision as cognitive accident prevention for the fail safe measures was proposed.

"사회복지통합서비스 시스템"의 DB암호화에 대한 리스크분석 및 대안연구 (Risk Analysis and Alternatives on DB Encryption of Social Welfare consolidation Service System)

  • 함승목;박태형
    • 디지털산업정보학회논문지
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    • 제9권4호
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    • pp.81-94
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    • 2013
  • Recently, the dramatical increasement of personal information infringement makes the government strongly enforce the laws. The Key-point of law enforcement is the DB encryption. Nevertheless, DB encryption is the one of the hardest thing in the organization's security measures. The purpose of this paper is suggesting alternative means of residence numbers and showing the possibility of indicator usage for safety measures. This research suggested the best ways to make a decision through a before and after comparison of the DB encryption cost of the inherent identification number elimination in "Social Welfare consolidation service system". When this research result was applied in "Happiness-e-Um system", we found that the alternative means are more efficient than the residence number for encryption cost, system revision time and so on.

Impostor Detection in Speaker Recognition Using Confusion-Based Confidence Measures

  • Kim, Kyu-Hong;Kim, Hoi-Rin;Hahn, Min-Soo
    • ETRI Journal
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    • 제28권6호
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    • pp.811-814
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    • 2006
  • In this letter, we introduce confusion-based confidence measures for detecting an impostor in speaker recognition, which does not require an alternative hypothesis. Most traditional speaker verification methods are based on a hypothesis test, and their performance depends on the robustness of an alternative hypothesis. Compared with the conventional Gaussian mixture model-universal background model (GMM-UBM) scheme, our confusion-based measures show better performance in noise-corrupted speech. The additional computational requirements for our methods are negligible when used to detect or reject impostors.

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Why Standard Measures of Human Capital are Misleading

  • HANUSHEK, ERIC A.
    • KDI Journal of Economic Policy
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    • 제37권2호
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    • pp.22-39
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    • 2015
  • After a long, dormant period, recent attention has turned to a variety of measurement issues surrounding the concept of human capital. The traditional approach of rely entirely on measures of school attainment, while convenient, is almost certainly misleading. The availability of cognitive skills measures greatly improves on these measurements, but there remains also concern about other unmeasured factors, including noncognitive skills. This paper considers alternative approaches to assessing the role of human capital on individual earnings and on economic growth.

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고용보조지표를 활용한 청년실업과 경기상관 분석 (Business Cycle Analysis on Korean Youth Labor Market using Alternative Unemployment Measures)

  • 김태봉;박근형
    • 경제분석
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    • 제26권2호
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    • pp.43-71
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    • 2020
  • 본 논문은 최근 높아진 청년실업의 경기상관성에 대한 특징을 분석하여, 거시경제학적 관점에서의 시사점을 도출하고자 하였다. 실증분석 결과, 청년실업은 경기상관성이 다른 연령층에 비해서 상대적으로 낮은 것으로 보이며, 최근 잠재경제활동인구를 중심으로 지속적으로 상승한 것을 경기변동 요인만으로 해석하기에는 어려운 것으로 판단된다. 한편, 잠재경제활동인구를 포함한 확장된 개념의 청년고용보조지표는 장기적인 상승 추세를 보이며, 총산출과의 공적분 관계를 지니고 있는 것으로 추정되었다. 이러한 추세적인 증가는 다른 연령층과는 달리 우리나라의 경제성장 경로 상에 내재되어 있는 구조적인 요인들로 부터 영향을 받았을 가능성이 있다는 것을 시사한다. 한편, 기업 규모에 따른 임금 격차가 외환위기 이후로 꾸준히 커졌다는 점과 상대적으로 양질의 일자리를 제공하는 대기업 취업자 비중이 주요 선진국에 비해서 상당히 낮은 수준이라는 점은 청년층 노동시장의 구조적인 변화를 반영한다고 볼 수 있다. 이러한 구조변화 속에서 청년층의 구직활동 기간이 길어지는 현상이 앞선 실증분석 결과로 나타난 것으로 사료된다.

동남권 잔골재수급 부족 문제를 해결할 대체골재 확보 가능성에 관한 연구 (A Study on the Possibility of Securing Alternative Aggregates to Solve the Problem of Supply and Demand of Fine Aggregate in Southeast Region)

  • 김하석;이도헌;김진만
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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    • pp.328-329
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    • 2018
  • The problem of imbalance between supply and demand of fine aggregates in the southeastern region due to the decrease in collection of EEZ(Exclusive Economic Zone) sea sand has been raised. In this paper, the possibility of securing alternative aggregate as a means to solve the problem of fine aggregate shortage in the southeast region was analyzed. As a result of the analysis, the alternative aggregate is easy to manufacture and its quality can be secured. And, it is suitable to use as an aggregate with less environmental burden. In addition, institutional improvement measures are needed for effective utilization and recycling of alternative aggregates.

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Viterbi 탐색 특성을 이용한 미등록어휘 제거에 대한 연구 (A Study on OOV Rejection Using Viterbi Search Characteristics)

  • 김규홍;김회린
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2005년도 춘계 학술대회 발표논문집
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    • pp.95-98
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    • 2005
  • Many utterance verification (UV) algorithms have been studied to reject out-of-vocabulary (OOV) in speech recognition systems. Most of conventional confidence measures for UV algorithms are mainly based on log likelihood ratio test, but these measures take much time to evaluate the alternative hypothesis or anti-model likelihood. We propose a novel confidence measure which makes use of a momentary best scored state sequence during Viterbi search. Our approach is more efficient than conventional LRT-based algorithms because it does not need to build anti-model or to calculate the alternative hypothesis. The proposed confidence measure shows better performance in additive noise-corrupted speech as well as clean speech.

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