To reduce the spectral distortion,a Hidden Markov Model-based narrowband speech bandwidth extension algorithm is presented.Firstly,the parameters which have higher mutual information with wideband envelope were extrac...To reduce the spectral distortion,a Hidden Markov Model-based narrowband speech bandwidth extension algorithm is presented.Firstly,the parameters which have higher mutual information with wideband envelope were extracted to constitute the feature vector,and then a posterior probability was calculated via the joint probability of the partial observation feature vector sequence and the markov states.Secondly,based on the posterior probability,the wideband envelope was estimated using Bayesian parameter estimation method and minimum mean square error criteria.For estimation of wideband excitation signal,intermediate frequency extension algorithm is proposed based on the harmonic correlation between the low frequency and high frequency.The experimental results show that,compared with the traditional bandwidth extension algorithm based on Hidden Markov Model,the average spectral distortion is reduced by 0.187 dB and the number of speech frame with spectral distortion over10dB is decreased by 34.3%.展开更多
Agricultural extension is an approach to rural development and agricultural transformation in which training,demonstration and technology transfer are key to reducing rural poverty,ensuring food security,and sustainab...Agricultural extension is an approach to rural development and agricultural transformation in which training,demonstration and technology transfer are key to reducing rural poverty,ensuring food security,and sustainably managing natural resources.During recent decades,different extension approaches have been tested and validated by the Ethiopian government and nongovernmental organizations to stimulate participation in the agricultural extension system(AES).The most recent was a German-funded project entitled“Integrated Soil Fertility Management Project”(ISFM+),which employed a novel approach to piloting and upscaling proven technology and best practice.The purpose of this study was to analyze and document the modalities of ISFM+and illustrate its effects on technology uptake and dissemination.The study used a mixed methods approach to collect data.ATLAS.ti and SPSS were used for data management and analysis.Farmer Research and Extension Groups and Farmer Field Schools were found to be central to the participation process.Also,the ISFM+was found to aid technology transfer and helped to increase grain and residue yields as well as farmer livelihoods.Based on these empirical findings,it is argued that the ISFM+approach and technology should be integrated and institutionalized in the mainstream AES in order to promote their extensive application.展开更多
文摘To reduce the spectral distortion,a Hidden Markov Model-based narrowband speech bandwidth extension algorithm is presented.Firstly,the parameters which have higher mutual information with wideband envelope were extracted to constitute the feature vector,and then a posterior probability was calculated via the joint probability of the partial observation feature vector sequence and the markov states.Secondly,based on the posterior probability,the wideband envelope was estimated using Bayesian parameter estimation method and minimum mean square error criteria.For estimation of wideband excitation signal,intermediate frequency extension algorithm is proposed based on the harmonic correlation between the low frequency and high frequency.The experimental results show that,compared with the traditional bandwidth extension algorithm based on Hidden Markov Model,the average spectral distortion is reduced by 0.187 dB and the number of speech frame with spectral distortion over10dB is decreased by 34.3%.
基金part of the ISFM^(+) which is financed by the German Federal Ministry of Economic Cooperation and Development。
文摘Agricultural extension is an approach to rural development and agricultural transformation in which training,demonstration and technology transfer are key to reducing rural poverty,ensuring food security,and sustainably managing natural resources.During recent decades,different extension approaches have been tested and validated by the Ethiopian government and nongovernmental organizations to stimulate participation in the agricultural extension system(AES).The most recent was a German-funded project entitled“Integrated Soil Fertility Management Project”(ISFM+),which employed a novel approach to piloting and upscaling proven technology and best practice.The purpose of this study was to analyze and document the modalities of ISFM+and illustrate its effects on technology uptake and dissemination.The study used a mixed methods approach to collect data.ATLAS.ti and SPSS were used for data management and analysis.Farmer Research and Extension Groups and Farmer Field Schools were found to be central to the participation process.Also,the ISFM+was found to aid technology transfer and helped to increase grain and residue yields as well as farmer livelihoods.Based on these empirical findings,it is argued that the ISFM+approach and technology should be integrated and institutionalized in the mainstream AES in order to promote their extensive application.
