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Electric-stimulus rate encoding algorithm of Mandarin tonal information in cochlear implant

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Progress in Natural Science:Materials International 2006年第12期16卷 1315-1321页

作者： GUAN Tian~1. GONG Qin~1.and YE Datian~2**(1. Department of Biomedical Engineering, Tsinghua university, Beijing 1.0084, China 2. Research Center of Biomedical Engineering, {1. School at Shenzhen, Tsinghua university, Shenzhen 51.055, China) [a]Department of Biomedical Engineering Tsinghua University Beijing China [b]Research Center of Biomedical Engineering Graduate School at Shenzhen Tsinghua University Shenzhen China

The modern multi-channel cochlear implants usually extract and encode the temporal envelope cues. This kind of algorithms can hardly satisfy the users who speak tonal languages, such as Mandarin. Many studies have tried to enhance the recognition ability of Mandarin through encoding tonal information and made suggestions to frequency-modulate the fixed pulse-rate carrier with the extracted tonal information based on the rate-pitch theory in electric hearing. However, how to encode and deliver the tonal information such as F_0by changing electric-stimulus rate has not got further study in clinical electric-stimulus mode. The present paper focuses on this matter by piecewise calculating the appreciable electric-stimulus rates. Then an electric-stimulus encoding algorithm of Mandarin tone is brought forward and testified through acoustic simulations. Such conclusion can be drawn that this algorithm of electric-stimulus rate could convey tonal information well and help to enhance the Mandarin speech recognition ability.

关键词： cochlear implant tone fundamental frequency electric-stimulus rate.

Relationship between surface subsidence factor and mining depth of strip pillar mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 594-598页

作者： GUO Wen-bing1. 2, HOU Quan-lin 1. ZOU You-feng2 1. College of Earth Science, graduate {1. of Chinese Academy of Sciences, Beijing 1.0049, China 2. School of Energy Science and Engineering, Henan Polytechnic {1., Jiaozuo 454000, China Chinese Acad Sci Coll Earth Sci Grad Univ Beijing 100049 Peoples R China Henan Polytech Univ Sch Energy Sci & Engn Jiaozuo 454000 Peoples R China

Strip pillar mining is one of the most important technical measures to control mining subsidence in China. Mining depth is one of the most important factors that can affect the mining subsidence in strip pillar mining. Six numerical simulation models were set up to simulate the surface subsidence of strip pillar mining in different mining depths. The mining depth in these six models ranges from 300 to 800 m. The simulated results were compared and analyzed. The formula was established based on the simulated results. It demonstrated that the subsidence of strip pillar mining method is related to mining depth. While the other conditions are the same, the subsidence of strip pillar mining increases with the increase of mining depth by logarithmic relationship.

关键词： subsidence factor strip pillar mining mining depth numerical simulation

Fluorescence fluctuation spectroscopy and its artifacts:simulations and tests

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 336-344页

作者： MENG Fanbo 1., CHEN Bo 1., LIU Guang 1., DING Jianying 1.& MA Hui 2,1.1. Department of Physics and Key Laboratory of Atomic and Molecular Nano Sciences, Ministry of Educa- tion, Tsinghua university, Beijing 1.0084, China 2. {1. School at Shenzhen, Tsinghua university, Shenzhen 51.055, China 1. Department of Physics and Key Laboratory of Atomic and Molecular Nano Sciences Ministry of Education Tsinghua University 100084 Beijing China 2. graduate School at Shenzhen Tsinghua University 518055 Shenzhen China

Fluorescence fluctuation spectroscopy (FFS) technique is capable of monitoring changes in concentration, mass, size and structure of fluorescent-labeled bio-molecules in microscopic volume and is suitable for measuring biological interactions in living cells. FFS data may be affected by many experimental factors in complicated biological systems. Using a Monte Carlo approach, we generate fluorescence fluctuation data for different experimental systems. This approach helps to separate the contributions by different experimental factors in a complicated fluorescence fluctuation spectrum. It also helps to validate new theoretical models and new fitting formulations. We describe the algorithm of the simulation program and tests on its statistical performance. The program is then used successfully to study the effects of several experimental factors on FFS detection.

关键词： fluorescence fluctuation spectroscopy, fluorescence correlation spectroscopy, Monte Carlo simulation.

Cloning and characterization of interferon stimulated genes Viperin and ISG1.,and their promoters from snakehead Channa argus

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Progress in Natural Science:Materials International 2007年第12期17卷 1425-1435页

作者： Jia Weizhang1.2, Zhou Xiuxia1.2, Huang Rong1.2 and Guo Qionglin1.1. Institute of Hydrobiololgy, Chinese Academy of Sciences, Wuhan 430072, China 2. graduate {1. of Chinese Academy of Sciences, Beijing 1.0039, China) Institute of Hydrobiololgy Chinese Academy of Sciences Wuhan 430072 China graduate {1. of Chinese Academy of Sciences Beijing 100039 China

By suppression subtractive hybridization, rapid amplification of cDNA ends and gene walking methods, interferon stimulated genes (ISGs), Viperin and ISG1., and their promoters have been cloned and characterized from snakehead Channa argus. The Viperin cDNA was found to be 1.74 nt and contain an open reading frame (ORF) of 1.59 nt that translates into a putative peptide of 352 amino acid (aa). The putative peptide of Viperin shows high identity to that in teleosts and mammals except for the N-terminal 70 aa. The ISG1. cDNA was found to be 758 nt and contain an ORF of 468 nt that translates into a putative peptide of 1.5 aa. The putative peptide of ISG1. is composed of two tandem repeats of ubiquitin-like (UBL) domains, and a canonical conjugation motif (LRGG) at C-terminal. Viperin and ISG1. promoter regions were characterized by the presence of interferon stimulating response elements (ISRE) and γ-IFN activation sites (GAS). ISRE is a feature of IFN-induced gene promoter and partially overlaps interferon regulatory factor (IRF) 1.and IRF2 recognition sites. GAS is responsible for the γ-IFN mediated transcription. One conserved site for NF-κB was found in the promoter region of Viperin. This is the first report of conservative binding motif for NF-κB in accordance with the consensus sequence (GGGRNNYYCC) among teleost ISG promoters. Moreover, there were also TATA, CAAT and Sp1.transcription factor sites in Viperin and ISG1. promoters. In 5′ untranslated region (UTR), snakehead ISG1. gene contains a single intron, which differs from Viperin gene. The transcripts of Vipeirn and ISG1. mRNA were mainly expressed in head kidney, posterior kidney, spleen and gill. The expression levels in liver were found to increase obviously in response to induction by IFN-inducer poly I∶C.

关键词： interferon interferon stimulated gene (ISG) Viperin ISG1. snakehead (Channa argus).

Dynamic learning rates algorithm for BPNN to forecast time series of dam security

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Progress in Natural Science:Materials International 2007年第12期17卷 1527-1530页

作者： Hu Daiping1. Wu Ruiming1. Lei Aizhong1.and Wang Qi2(1. Antai College of Economics & Management, Shanghai Jiaotong university, Shanghai 200052, China 2. {1. School, Lanzhou university, Lanzhou 730000, China) Antai College of Economics & Management Shanghai Jiaotong University Shanghai 200052 China graduate School Lanzhou University Lanzhou 730000 China

Time series data of dam security have a large number of observed values and should be forecasted accurately in time. Neural networks have the powerful approach ablilities of arbitrary functions and have been broadly utilized in many domains. In this paper, a dynamic learning rate training algorithm of back-propagation neural networks for time series forecasting is proposed and the networks with this algorithm are built to forecast time series of dam security. The application results demonostrate the efficiency of modelling and the effictiveness of forecasting.

关键词： neural network dynamic learning rate forecasting dam security.

Statistical distribution of nonlinear random wave height

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Science China Earth Sciences 2006年第4期49卷 443-448页

作者： HOU Yijun1. GUO Peifang1.2, SONG Guiting1.2, SONG Jinbao1. YIN Baoshu1.& ZHAO Xixi1.2 1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071. China 2. graduate {1. of the Chinese Academy of Sciences, Beijing 1.0039, China 1. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. graduate {1. of the Chinese Academy of Sciences Beijing 100039 China

A statistical model of random wave is developed using Stokes wave theory of water wave dynamics. A new nonlinear probability distribution function of wave height is presented. The results indicate that wave steepness not only could be a parameter of the distribution function of wave height but also could reflect the degree of wave height distribution deviation from the Rayleigh distribution. The new wave height distribution overcomes the problem of Rayleigh distribution that the prediction of big wave is overestimated and the general wave is underestimated. The prediction of small probability wave height value of new distribution is also smaller than that of Rayleigh distribution. Wave height data taken from East China Normal university are used to verify the new distribution. The results in- dicate that the new distribution fits the measurements much better than the Rayleigh distribution.

关键词： Random ocean wave, nonlinearity, wave height distribution.

Properties and applications of cold supersonic gas jet

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Science China(Physics,Mechanics & Astronomy) 2006年第6期49卷 709-715页

作者： ZHANG Shaofeng1.2,MA Xinwen1.2,LIU Huiping2,LI Bin1.2 & ZHU Xiaolong1.2 1. Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China 2. graduate {1. of Chinese Academy of Sciences,Beijing 1.0049,China 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. graduate {1. of Chinese Academy of Sciences Beijing 100049 China

By analyzing the formation mechanism of a supersonic gas jet,a set of equations which describe the atomic beam properties were established. The influence of initial temperature,initial pressure,background gas pressure and pumping speed was discussed in detail. A simulation program was developed based on the equations,and the results under different initial conditions were obtained. The results are in good agreement with the experimental data,and suggest that,in order to get much smaller transverse momentum in collision experiments,it is necessary to lower the initial temperature and the initial pressure of the supersonic gas jet,together with increasing the pumping speed. These results are very instructive for construction of a new generation of cold supersonic gas jets.

关键词： cold supersonic gas jet,zone of silence,nozzle,skimmer.

Microcosmic analysis of ductile shearing zones of coal seams of brittle deformation domain in superficial lithosphere

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Science China Earth Sciences 2004年第5期47卷 393-404页

作者： JU Yiwen1.2, WANG Guiliang2, JIANG Bo2 & HOU Quanlin1.1. graduate School, Chinese Academy of Sciences, Beijing 1.0039, China 2. College of Mineral Resources and Geosciences, China {1. of Mining & Technology, Xuzhou 221.08, China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China China Univ Min & Technol Coll Mineral Resources & Geosci Xuzhou 221008 Peoples R China

The ductile shearing zones of coal seams in a brittle deformation domain in super-ficial lithosphere are put forward based on the study on bedding shearing and ductile rheology of coal seams. The macrocosmic and microcosmic characteristics include wrinkle fold, mymonitized zones and ductile planar structure of coal seams, etc., while the microcosmic characteristics may also include different optic-axis fabrics and the anisotropy of vitrinite reflectance as well as the change of chemical structure and organic geochemistry components. The forming mechanism is analyzed and the strain environment of ductile shearing zones of coal seams discussed. The result indicates that, in the superficial brittle deformation domain, the coal seams are easy to be deformed, resulting in not only brittle deformation but also ductile shearing deformation under the action of force. Because of simple shearing stress, the interlayer gliding or ductile rheology may take place between coal seams and wall rocks. Therefore, many ductile shearing zones come into being in superficial lithosphere (<5 km). The research on ductile shearing zone of brittle de-formation domain in superficial lithosphere is significant not only theoretically for the study of ductile shearing and ductile rheology of the lithosphere but also practically for the structural movement of coal seams, the formation and accumulation of coal-bed methane, and the preven-tion and harness of gas burst in coal mine.

关键词： brittle deformation domain, interlayer gliding, ductile rheology, ductile shearing zones of coal seams, coal mymonite, vitrinite reflectance anisotropy.

Transient species and its properties of melatonin

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Science China Chemistry 2006年第4期49卷 308-314页

作者： ZHU Hongping1.2, ZHANG Zhaoxia1.2, ZHAO Hongwei1. WANG Wenfeng1.& YAO Side1.1. Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201.00, China 2. graduate {1. of the Chinese Academy of Sciences, Beijing 1.0049, China 1. Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 2. graduate {1. of the Chinese Academy of Sciences Beijing 100049 China

The photo-physical and photo-chemical properties of melatonin (ML) werestudied by 266 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radicalcation of ML (ML^(·+))and hydrated electrons (e_(aq)^-), while excited triplet state ~3ML~* is alsoformed during photolysis. The oxidation via one electron transfer from ML to SO_4^(·+) and thetriplet state of riboflavin (~3RF~*) has been also investigated and the rate constants for theprocess have been determined to be 8.0x1.^9 and 1.4x1.^9 L·mol^(-1.·s^(-1. respectively. Theradical cation of 2,2''-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS^(·+)) scavengingcapacities of melatonin and other antioxidants are compared in this paper.

关键词： melatonin, laser flash photolysis, photoionization, triplet state.