• 제목/요약/키워드: Combining weights

검색결과 93건 처리시간 0.034초

민감도 분석에 의한 LHR 모형의 검증 (Verification of Landfill Hazard Ranking Model by Sensitivity Analysis)

  • 홍상표;김정욱
    • 환경영향평가
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    • 제6권2호
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    • pp.113-121
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    • 1997
  • LHR(Landfill Hazard Ranking Model) was developed for assessing the relative hazard of landfills by using the method of value-structured approach. LHR consists of combining a multiattribute decision-making method with a qualitative risk assessment approach. A pairwise comparision method was applied to determine weights of landfill factors related. To prove the validity of weights allocation of landfill hazard evaluation factors, sensitivity analysis was applied. Firstly, the impact on landfill hazard score according to variations of weights of landfill hazard factors was analyzed. Secondly, the impact on landfill hazard score according to conditions change of landfill hazard factors was analyzed. As a result of sensitivity analysis, LHR composite scores are largely influenced by some factors following sequential order such as waste volume, proximity to sensitive environments, containment facilities, distance from drinking water supplies, and waste toxicity. The relative order of landfill hazard evaluated by LHR is not influenced by the weights change of individual factors. Therefore, LHR seems to be a credible model to determine priorities of landfill remediation based on the vulnerability of water resources.

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A DIFFERENCE EQUATION FOR MULTIPLE KRAVCHUK POLYNOMIALS

  • Lee, Dong-Won
    • 대한수학회지
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    • 제44권6호
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    • pp.1429-1440
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    • 2007
  • Let ${K^{(\vec{p};N)}_{\vec{n}}(x)}$ be a multiple Kravchuk polynomial with respect to r discrete Kravchuk weights. We first find a lowering operator for multiple Kravchuk polynomials ${K^{(\vec{p};N)}_{\vec{n}}(x)}$ in which the orthogonalizing weights are not involved. Combining the lowering operator and the raising operator by Rodrigues# formula, we find a (r+1)-th order difference equation which has the multiple Kravchuk polynomials ${K^{(\vec{p};N)}_{\vec{n}}(x)}$ as solutions. Lastly we give an explicit difference equation for ${K^{(\vec{p};N)}_{\vec{n}}(x)}$ for the case of r=2.

Soft Combination Schemes for Cooperative Spectrum Sensing in Cognitive Radio Networks

  • Shen, Bin;Kwak, Kyung-Sup
    • ETRI Journal
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    • 제31권3호
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    • pp.263-270
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    • 2009
  • This paper investigates linear soft combination schemes for cooperative spectrum sensing in cognitive radio networks. We propose two weight-setting strategies under different basic optimality criteria to improve the overall sensing performance in the network. The corresponding optimal weights are derived, which are determined by the noise power levels and the received primary user signal energies of multiple cooperative secondary users in the network. However, to obtain the instantaneous measurement of these noise power levels and primary user signal energies with high accuracy is extremely challenging. It can even be infeasible in practical implementations under a low signal-to-noise ratio regime. We therefore propose reference data matrices to scavenge the indispensable information of primary user signal energies and noise power levels for setting the proposed combining weights adaptively by keeping records of the most recent spectrum observations. Analyses and simulation results demonstrate that the proposed linear soft combination schemes outperform the conventional maximal ratio combination and equal gain combination schemes and yield significant performance improvements in spectrum sensing.

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Precipitation rate with optimal weighting method of remote sensed and rain gauge data

  • Oh, Hyun-Mi;Ha, Kyung-Ja;Bae, Deg-Hyo;Suh, Ae-Sook
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1171-1173
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    • 2003
  • There are two datasets to estimate the area-mean and time-mean precipitation rate. For one, an array of surface rain gauges represents a series of rods that have to the time axis of the volume. And another data is that of a remote sensing make periodic overpasses at a fixed interval such as radar. The problem of optimally combining data from surface rain gauge data and remote sensed data is considered. In order to combining remote sensed data with Automatic Weather Station (AWS), we use optimal weighting method, which is similar to the method of [2]. They had suggested optimal weights that minimized value of the mean square error. In this paper, optimal weight is evaluated for the cases such as Changma, summer Monsoon, Typhoon and orographic rain.

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Pilot Symbol Assisted Weighted Data Fusion Scheme for Uplink Base-Station Cooperation System

  • Zhang, Zhe;Yang, Jing;Zhang, Jiankang;Mu, Xiaomin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권2호
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    • pp.528-544
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    • 2015
  • Base Station Cooperation (BSC) has been a promising technique for combating the Inter-Cell Interference (ICI) by exchanging information through a high-speed optical fiber back-haul to increase the diversity gain. In this paper, we propose a novel pilot symbol assisted data fusion scheme for distributed Uplink BSC (UBSC) based on Differential Evolution (DE) algorithm. Furthermore, the proposed scheme exploits the pre-defined pilot symbols as the sample of transmitted symbols to constitute a sub-optimal Weight Calculation (WC) model. To circumvent the non-linear programming problem of the proposed sub-optimal model, DE algorithm is employed for searching the proper fusion weights. Compared with the existing equal weights based soft combining scheme, the proposed scheme can adaptively adjust the fusion weights according to the accuracy of cooperative information, which remains the relatively low computational complexity and back-haul traffic. Performance analysis and simulation results show that, the proposed scheme can significantly improve the system performance with the pilot settings of the existing standards.

Co-Channel Interference Cancellation in Cellular OFDM Networks PART II: Co-Channel Interference Cancellation in Single Frequency OFDM Networks using Soft Decision MLE CCI Canceler

  • Mohaisen, Manar;Chang, Kyung-Hi
    • 한국통신학회논문지
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    • 제32권7A호
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    • pp.710-716
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    • 2007
  • 본 논문에서는 OFDM 셀룰라 네트워크에서 셀 가장자리에 위치한 사용자를 위한 다운링크 동일채널간섭(CCI) 제거 기법을 소개한다. 기지국간의 협력적 심볼 전송은 동일 심볼을 다른 기지국에서 상이한 부반송파를 사용하여 전송함으로서 이루어진다. 단말기에서는 전송된 심볼을 추정하기 위하여 연판정 최대우도 동일채널간섭 제거기(soft decision maximum likelihood CCI canceler)와 수정된 최대비 합성법 (modified maximum ratio combining (M-MRC))을 적용하며, 합성법에 사용된 가중치는 협력 기지국과 단말기 사이의 채널 상수에 의해서 유도된다. 시뮬레이션 결과로부터 제안된 기법이 주파수 선택적 페이딩 채널과 주파수 비선택적 페이딩 채널에서 각기 9 dB와 6dB의 SIR 이득을 보임을 알 수 있다.

이동 로봇 행위의 진화 (Evolutionary Learning of Mobile Robot Behaviors)

  • 이재구;심인보;윤중선
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1105-1108
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    • 2003
  • Adaptation in dynamic environments gains a significant advantage by combining evolution and learning. We propose an on-line, realtime evolutionary learning mechanism to determine the structure and the synaptic weights of a neural network controller for mobile robot navigations. We support our method, based on (1+1) evolutionary strategy, which produces changes during the lifetime of an individual to increase the adaptability of the individual itself, with a set of experiments on evolutionary neural controller for physical robots behaviors.

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가뭄지수의 적용성 분석을 통한 가뭄의 정량적 표현기법 개발 (Development of Quantitative Drought Representation Methods by Drought Index Application)

  • 정상만;이주헌;김이형;김하용
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2006년도 학술발표회 논문집
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    • pp.1166-1171
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    • 2006
  • Drought is defined by differently for the several scientific and technical fields such as hydrological drought, agricultural drought, meteorological drought, climatological drought, atmospheric drought. A lot of drought indices have been developed to quantify drought severity levels. However these drought indices might be expressed differently as the drought conditions for specific period because the drought severity level is using different types of data on each condition. It is necessary for development of quantative drought representation methods by drought index application. In this research, the reaction to the historical droughts is analyzed after estimation of PDSI, SPI and MSWSI(Modified Surface Water Supply Index) in south korean territory. Lastly the drought representation methods were examiner combining the drought indices by drought indices. The arithmetic mean drought indices that include PDSI, SPI, in yearly basis from 1971 to 2001 and MSWSI in yearly basis from 1974 to 2001 were estimated through the whole nation. The applicability of drought indices are examined based on the observed drought data for national and regional droughts. The result shows that PDSI, SPI(3), SPI(6), and MSWSI have proven to be sensitive enough to the historical drought. The correlation analysis of each drought index was conducted whether they could show the long and short term drought equally. The analysis of how appropriately represent for the historical drought was used for determining for the combined drought index. Consequently, PDSI, SPI(3), SPI(6), and MSWSI have been appeared as suitable indices for the development of quantitative drought representation methods. For the decision of weight on combining PDSI, SPI(3), SPI(6), and MSWSI, drought map was made for eighteen alternative to decide weight. The results showed that PDSI(20%), SPI(3)(60%), SPI(6)(10%), and MSWSI(10%) have been the most well matched weights. Using selected weights of each drought indices and by reconstructing the national mean drought severity on yearly basis, the fact that the year of historical drought is in accordance with the verified one for drought representation. In short, the acquired technique using combined drought index can be used for useful and believable quantitative method of drought analysis.

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팬지의 일대 잡종에서 생육관련 형질의 상관관계 및 조합능력 (Correlation and Combining Ability related to the Growth Characteristics in F1 Hybrids by Diallel Cross of Viola tricolor)

  • 송천영;홍규현;강윤규;이관호;김종칠
    • 현장농수산연구지
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    • 제4권1호
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    • pp.70-79
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    • 2002
  • 팬지 7개 계통을 이면교잡한 F1 21개 조합 및 양친에 대한 엽장, 엽폭, 엽병장, 분지수, 엽수, 엽면적, 생체중, 건물중 및 개화수 등의 형질에 대하여 상호관계 및 조합능력을 분석하였다. 엽장과 엽폭은 엽병장과 유의성이 인정되는 정의 상관관계를 보였고 분지수, 엽수 및 개화수와는 부의 상관관계를 나타냈다. 엽수는 화수와의 사이에, 엽면적은 생체중과 건물중 사이에 정의 상관관계를 나타냈다. 개화수는 엽수, 분지수와 정의 상관관계를 보였고 엽장, 엽폭과는 부의 상관관계를 나타냈다. 조합능력의 분산은 일반조합능력이나 특수조합능력 모두 8가지 형질에서 유의성이 인정되었으며 엽장을 제외한 모든 형질에서 특수조합능력의 분산 구성분이 일반조합능력의 분산 구성분보다 크게 작용하였다. 모본의 일반조합능력검정에서 C와 G계통은 엽장과 엽폭의 증가에 대한 효과가 컸으며, A와 F계통은 엽수 증가의 효과가 컸고 A, B계통과 G계통은 엽면적 증가의 일반조합능력 효과가 뚜렷하였다. 또한 B와 D계통은 생체중 증가의, B와 F계통은 개화수 증가의 일반조합능력 효과가 컸다. 특수조합능력 효과에서 엽장, 엽폭, 엽수, 및 생체중 등의 생육이 증가되고 개화수가 많아진 조합은 A×B조합과 B×D조합이었고, 엽장, 엽면적 및 생체중이 감소하고 개화수가 증가된 조합은 B×E조합과 D×G조합이었다. 유전력은 9가지 형질 모두 광의의 유전력이 크게 나타났고 생체중을 제외한 엽장, 엽폭, 엽병장, 분지수, 엽수, 엽면적, 건물중 및 개화수 등의 모든 형질에서 광의와 협의의 유전력 모두가 높게 나타났다.

육용계의 복강지방축적에 대한 결합능력추정연구 (Estimation of the Combining Abilities of Abdominal Eat Deposition of Broiler)

  • 정선부;정일정
    • 한국가금학회지
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    • 제10권2호
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    • pp.83-89
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    • 1983
  • 본 연구는 육용계의 복강지방 축적에 대한 결합능력추정을 위하여 White Cornish 2계통과White Plymouth Rock 2계통을 상호 역교배시켜 16개 교배조합을 생산하여 각 교배조합당 60수씩 960수를 혈통번식시켜 2주 간격으로 체중, 복강지방량 및 체중에 대한 복강지방 비율에 대한 결합능력을 추정하였다. 1. 육계의 복강지방량의 생체중 대 비율은 4주영부터 암탉이 수탉보다 높았다. 2. 일반결합능력에 있어서 체중은 암수 공히 각주령에 유의성이 있었으며 복강지방량에서 암탉은 2. 8, 10 및 12주령에 유의성이 있었고 수탉은 2, 6 및 12주령에 유의성이 있었으며 복강지방의 생체중 대 비율에서는 암탉은 10 및 12주령에 유의성이 있었으나 수탉에서는 유의성이 없었다. 3. 특수결합능력에서 체중은 암탉에서 4, 6, 10 및 12주령 수탉에서 4, 8, 및 12주령에 유의성이 있었으며 복강지방량은 암탉에서 4, 8, 10 및 12주령에 유의성이 있었으나 수탉에서는 유의성이 없었으며 복강지방의 생체량 대 비율은 암탉에서 4 및 8주령에 유의성이 있었으나 수탉에서는 유의성이 없었다.

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