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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 100084, China 2. {2. center of Biomedical engineering, Graduate School at Shenzhen, Tsinghua university, Shenzhen 518055, China) Department of Biomedical engineering Tsinghua University Beijing 100084 China research center of Biomedical {2. Graduate School Shenzhen Tsinghua University Shenzhen 518055 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.

Polynomial analysis of canopy spectra and biochemical component content inversion

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Science China Earth Sciences 2005年第10期48卷 1780-1791页

作者： YAN Chunyan1, LIU Qiang1, NIU Zheng1, WANG Jihua2. HUANG Wenjiang2.& LIU Liangyun 2.1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal university, Beijing 100101, China 2. national {2. research center for Information Technology in Agriculture, Beijing 100089, China Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal university national engineering {2. center for Information Technology in Agriculture

A polynomial expression model was developed in this paper to describe directional canopy spectra, and the decomposition of the polynomial expression was used as a tool for re-trieving biochemical component content from canopy multi-angle spectra. First, the basic formula of the polynomial expression was introduced and the physical meaning of its terms and coeffi-cients was discussed. Based on this analysis, a complete polynomial expression model and its decomposition method were given. By decomposing the canopy spectra simulated with SAILH model, it shows that the polynomial expression can not only fit well the canopy spectra, but also show the contribution of every order scattering to the whole reflectance. Taking the first scattering coefficients a10 and a01 for example, the test results show that the polynomial coefficients reflect very well the hot spot phenomenon and the effects of viewing angles, LAI and leaf inclination angle on canopy spectra. By coupling the polynomial expression with leaf model PROSPECT, a canopy biochemical component content inversion model was given. In the simulated test, the canopy multi-angle spectra were simulated by two different models, SAILH and 4-SCALE re-spectively, then the biochemical component content was retrieved by inverting the coupled polynomial expression + PROSPECT model. Results of the simulated test are promising, and when applying the algorithm to measured corn canopy multi-angle spectra, we also get relatively accurate chlorophyll content. It shows that the polynomial analysis provides a new method to get biochemical component content independent of any specific canopy model.

关键词： polynomial expression, canopy spectra, decomposition, biochemical component content, inversion.

Deep-Cut Vacuum Distillation in the 10 Mt/a CDU/VDU

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China Petroleum Processing & Petrochemical Technology 2009年第2期11卷 9-13页

作者： Lin Zhuwei1 Mao Fuzhong1 Jiang Bing2.Chen Kaibei3 Chi Ling3 Yan Chun3(1. KBC Advanced Technologies(Beijing) Co.,Ltd. Beijing 10002. 2. The national engineering {2. center for rectification Technology,tianjin university 3. SINOPEC engineering Incorporation) KBC Advanced Technologies (Beijing) Co. Ltd. Beijing 100029 China national engineering {2. center for rectification Technology Tianjin University China SINOPEC engineering Incorporation China

This article introduces the concepts relating to deep-cut vacuum distillation and its suitability,and analyzes the deep-cut vacuum distillation technique licensed by the KBC Advanced Technologies to the 10 Mt/a CDU/VDU of the Qingdao refinery and makes comparison on the test run data after commissioning of the distillation unit. The test results have confirmed that the operation of the CDU/VDU had reached the expected goal to achieve good social and economic benefits.

关键词： CDU/VDU deep cut under vacuum distillation rate

Analysis of crack propagation in concrete structures with structural information entropy

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Science China(Technological Sciences) 2010年第7期53卷 1943-1948页

作者： BAO TengFei1’2. PENG Yan1’2. CONG PeiJiang1’2.& WANG JiaLin1’2.1 State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering, Hohai university, Nanjing 2.002., China 2.{2. engineering research center ofWater Resources Efficient Utilization and engineering Safety, Hohai university, Nanjing 2.002., China State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering Hohai University Nanjing China national engineering {2. center of Water Resources Efficient Utilization and engineering Safety Hohai University Nanjing China

The propagation of cracks in concrete structures causes energy dissipation and release, and also causes energy redistribution in the structures. Entropy can characterize the energy redistribution. To investigate the relation between the propagation of cracks and the entropy in concrete structures, cracked concrete structures are treated as dissipative structures. Structural information entropy is defined for concrete structures. A compact tension test is conducted. Meanwhile, numerical simulations are also carried out. Both the test and numerical simulation results show that the structural information entropy in the structures can characterize the propagation of cracks in concrete structures.

关键词： crack entropy concrete sun

A preliminary study on vegetation-erosion dynamics and its applications

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Science China Earth Sciences 2005年第5期48卷 689-700页

作者： WANG Zhaoyin 1,2., WANG Guangqian 1 , LI Changzhi 1 & WANG Feixin 1 1. Department of Hydraulic engineering, Tsinghua university, Beijing 100084, China 2. Inter{2. research and Training center on Erosion and Sedimentation, Beijing 100084, China Department of Hydraulic engineering Tsinghua University Beijing China International research and Training {2. on Erosion and Sedimentation Beijing China

Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

关键词： vegetation-erosion dynamics, human activities, coupled differential equations, erosion control, vigor ofvegetation.

Aspects of recent developments in analytical chemometrics

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Science China Chemistry 2006年第3期49卷 193-203页

作者： LIANG Yizeng1,2. WU Hailong1, SHEN Guoli1, JIANG Jianhui1, LIANG Sheng2.& YU Ruqin1 1. State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical engineering, Hunan university, Changsha 410082. China 2. {2. center of Modernization of Traditional Chinese Medicines, Central South university, Changsha 410081, China State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha China research center of Modernization of Traditional Chinese Medicines Central South University Changsha China

Some aspects of recent developments in analytical chemometrics are discussed, in par- ticular the developments viewed from the angle of the research efforts undertaken in authors’ labora- tories. The topics concerned include resolution of high-order chemical data, morphological theory and methodology for chemical signal processing, multivariate calibration and chemical pattern recognition for solving complex chemical problems, and resolution of two-way chemical data from hyphenated chromatographic instruments.

关键词： chemometrics, high-order chemical data, pattern recognition, multivariate calibration and resolution.

Thermal-stress Simulation of Direct-chill Casting of AZ31 Magnesium Alloy Billets

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Journal of Wuhan university of Technology(Materials Science) 2009年第3期24卷 376-382页

作者：胡红军 College of Materials Science and engineering Chongqing University national engineering {2. center for Magnesium Alloys Chongqing University College of Material Science and engineering Chongqing University of Technology

Two-dimensional （2.） transient coupled finite element model was developed to compute the temperature and stress field in cast billets, so as to predict the defects of the I-type billets made from AZ31 magnesium alloy and find the causes and solutions for surface cracks and shrinkages during direct-chill （DC） casting process. Method of equivalent specific heat was used in the heat conduction equation. The boundary and initial conditions used for primary and secondary cooling were elucidated on the basis of the heat transfer during the solidification of the billet. The temperature and the thermal-stress fields were simulated with the thermal-structural coupled module of ANSYS software. The influences of casting parameters on the distributions of temperature and stress were studied, which helped optimize the parameters （at pouring temperature of 680 ℃, casting speed of 2.min/s, heat-transfer coefficient of the second cooling equals to 5 000 W/m^2.℃^-1）. The simulation results of thermal stress and strain fields reveal the formation mechanism of some casting defects, which is favourable for optimizing the casting parameters and obtain high quality billets. Some measures of controlling processes were taken to prevent the defects for direct-chill casting billets.

关键词： magnesium alloy direct-chill casting temperature and stress fields numerical simulation solidification model

AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

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Science China Chemistry 2006年第3期49卷 256-266页

作者： GE Xiaopeng1, ZHOU Yanmei2. Lü Chunhua1 & TANG Hongxiao1 1. State Key Laboratory of Environmental Aquatic Chemistry, research center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 2. School of Civil {2. & Architecture, Beijing Jiaotong university, Beijing 100044, China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China School of Civil engineering & Architecture Beijing Jiaotong University Beijing China

Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the tianjin humic sample is found to form small spheres with 2.0 to 330 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indica- tive of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic sub- stances in the sorption of environmental pollutants.

关键词： atomic force microscopy (AFM) dissolved humic substances morphology aggregation adsorption

Influence of Formate on Bioactivity Material-thuringiensin Synthesized by Bacillus thuringiensis YBT-032

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Journal of Wuhan university of Technology(Materials Science) 2008年第5期23卷 691-693页

作者：王志喻子牛 College of Bioengineering Hubei University of Technology State Key Laboratoy of Agricultural Microbiology national engineering {2. center for Microbial Posticides Huazhong Agricultural University

The biological method to synthesize thuringiensin and the influence of formate on thuringiensin biosynthesis were investigated. Addition of 1.00 g/L formate to growth medium of bacillus thuringiensis YBT-032.resulted in significant enhancements in productions of citrate, α -ketoglutarate, intracellular adenine and thuringiensin. These results demonstrate that added formate attends metabolism of cell, facilitates carbon metabolic flux in tricarboxylic acid cycle and hexose monophosphate pathway. As a carbon source, formate facilitates cell growth, increases glucose consumption and enhances the ability of cell to synthesis adenine analogues, and subsequently thuringiensin. Thuringiensin production rate significantly enhanced from 6.44 to 8.46 mg·g^-1 · h and transformation ratio from glucose to thuringiensin increased by 43.30%.

关键词： bacillus thuringiensis precursor formate thuringiensin