A new joint decoding strategy that combines the character-based and word-based conditional random field model is proposed.In this segmentation framework,fragments are used to generate candidate Out-of-Vocabularies(OOV...A new joint decoding strategy that combines the character-based and word-based conditional random field model is proposed.In this segmentation framework,fragments are used to generate candidate Out-of-Vocabularies(OOVs).After the initial segmentation,the segmentation fragments are divided into two classes as "combination"(combining several fragments as an unknown word) and "segregation"(segregating to some words).So,more OOVs can be recalled.Moreover,for the characteristics of the cross-domain segmentation,context information is reasonably used to guide Chinese Word Segmentation(CWS).This method is proved to be effective through several experiments on the test data from Sighan Bakeoffs 2007 and Bakeoffs 2010.The rates of OOV recall obtain better performance and the overall segmentation performances achieve a good effect.展开更多
Room-temperature Ionic Liquids(ILs) have numerous unique properties that differ from those of conventional molecular solvents.Although the unique properties of ILs have been suggested to origin from their microscopic ...Room-temperature Ionic Liquids(ILs) have numerous unique properties that differ from those of conventional molecular solvents.Although the unique properties of ILs have been suggested to origin from their microscopic interionic interaction,detailed dynamics of interionic interaction of ILs has not been fully understood.Here,with the Femtosecond Optical Heterodyne-Detected Raman Induced Kerr Effect Spectroscopy(fs-OHD-RIKES),we measured the ultrafast dynamics of the interionic interaction of three typical imidazolium based ILs,1-butyl-3-methylimidazolium tetrafluoroborate([bmim][BF4]),1-butyl-3-methylimidazolium hexafluorophosphate([bmim][PF6]),and 1-decyl-3-methylimidazolium tetrafluoroborate([dmim][BF4]).We observed several periods of subpicosecond oscillation in their fs-OHD-RIKES signals.Through decomposing their fs-OHD-RIKES signals into four Brownian oscillators in time domain,we explored the cation and anion substitution effects on the ultrafast dynamics of interionic interaction of ILs.We found that the cation substitution affected all the low frequency motions we observed,while the anion substitution only affected the two higher low frequency motions.展开更多
In this paper,the RS-Turbo concatenated code is applied to coherent optical orthogonal frequency division multiplexing(CO-OFDM) system.RS(186,166,8) and Turbo code with code rate of 1/2 are employed for RS-Turbo conca...In this paper,the RS-Turbo concatenated code is applied to coherent optical orthogonal frequency division multiplexing(CO-OFDM) system.RS(186,166,8) and Turbo code with code rate of 1/2 are employed for RS-Turbo concatenated code.Two decoding algorithms,which are Max-Log-MAP algorithm and Log-MAP algorithm,are adopted for Turbo decoding,and the iteration Berlekamp-Massey(BM) algorithm is adopted for RS decoding.The simulation results show that the bit error rate(BER) performance of CO-OFDM system with RS-Turbo concatenated code is significantly improved at high optical signal to noise ratio(OSNR),and the iteration number is reduced compared with that of the Turbo coded system.Furthermore,when the Max-Log-MAP algorithm is adopted for Turbo decoding,the transmission distance of CO-OFDM system with RS-Turbo concatenated code can reach about 400 km without error,while that of the Turbo coded system can only reach about 240 km when BER is lower than 10^(-4) order of magnitude.展开更多
基金supported by the National Natural Science Foundation of China under Grants No.61173100,No.61173101the Fundamental Research Funds for the Central Universities under Grant No.DUT10RW202
文摘A new joint decoding strategy that combines the character-based and word-based conditional random field model is proposed.In this segmentation framework,fragments are used to generate candidate Out-of-Vocabularies(OOVs).After the initial segmentation,the segmentation fragments are divided into two classes as "combination"(combining several fragments as an unknown word) and "segregation"(segregating to some words).So,more OOVs can be recalled.Moreover,for the characteristics of the cross-domain segmentation,context information is reasonably used to guide Chinese Word Segmentation(CWS).This method is proved to be effective through several experiments on the test data from Sighan Bakeoffs 2007 and Bakeoffs 2010.The rates of OOV recall obtain better performance and the overall segmentation performances achieve a good effect.
基金supported by the National Natural Science Foundation of China (20733001,20803092)the Fundamental Research Funds for the Central Universitiesthe Research Funds of Renmin University of China (10XNI007,10XNJ008)
文摘Room-temperature Ionic Liquids(ILs) have numerous unique properties that differ from those of conventional molecular solvents.Although the unique properties of ILs have been suggested to origin from their microscopic interionic interaction,detailed dynamics of interionic interaction of ILs has not been fully understood.Here,with the Femtosecond Optical Heterodyne-Detected Raman Induced Kerr Effect Spectroscopy(fs-OHD-RIKES),we measured the ultrafast dynamics of the interionic interaction of three typical imidazolium based ILs,1-butyl-3-methylimidazolium tetrafluoroborate([bmim][BF4]),1-butyl-3-methylimidazolium hexafluorophosphate([bmim][PF6]),and 1-decyl-3-methylimidazolium tetrafluoroborate([dmim][BF4]).We observed several periods of subpicosecond oscillation in their fs-OHD-RIKES signals.Through decomposing their fs-OHD-RIKES signals into four Brownian oscillators in time domain,we explored the cation and anion substitution effects on the ultrafast dynamics of interionic interaction of ILs.We found that the cation substitution affected all the low frequency motions we observed,while the anion substitution only affected the two higher low frequency motions.
基金supported by the National Natural Science Foundation of China(No.61107052)Tianjin Natural Science Foundation of China(No.11JCYBJC0010)Tianjin Youth Foundation of China(No.13JCQNJC01800)
文摘In this paper,the RS-Turbo concatenated code is applied to coherent optical orthogonal frequency division multiplexing(CO-OFDM) system.RS(186,166,8) and Turbo code with code rate of 1/2 are employed for RS-Turbo concatenated code.Two decoding algorithms,which are Max-Log-MAP algorithm and Log-MAP algorithm,are adopted for Turbo decoding,and the iteration Berlekamp-Massey(BM) algorithm is adopted for RS decoding.The simulation results show that the bit error rate(BER) performance of CO-OFDM system with RS-Turbo concatenated code is significantly improved at high optical signal to noise ratio(OSNR),and the iteration number is reduced compared with that of the Turbo coded system.Furthermore,when the Max-Log-MAP algorithm is adopted for Turbo decoding,the transmission distance of CO-OFDM system with RS-Turbo concatenated code can reach about 400 km without error,while that of the Turbo coded system can only reach about 240 km when BER is lower than 10^(-4) order of magnitude.
