检索结果-南通市图书馆

A flexible framework for HMM based noise robust speech recognition using generalized parametric space polynomial regression

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2011年第12期54卷 2501-2511页

作者： CHENG Ning 1., LIU XunYing 1.2 & WANG Lan 1.1.Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences/The Chinese university of Hong Kong, Hong Kong, China 2 {1. university Engineering department, cambridge cb2 1.z, uk 1. Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences/The Chinese University of Hong Kong Hong Kong China2. Cambridge University Engineering Department Cambridge CB2 1PZ UK

Handling variable, non-stationary ambient noise is a challenging task for automatic speech recognition (ASR) systems. To address this issue, multi-style, noise condition independent (CI) model training using speech data collected in diverse noise environments, or uncertainty decoding techniques can be used. An alternative approach is to explicitly approximate the continuous trajectory of Gaussian component mean and variance parameters against the varying noise level, for example, using variable parameter hidden Markov model (VP-HMM). This paper investigates a more generalized form of variable parameter HMMs (GVP-HMM). In addition to Gaussian component means and variances, it can also provide a more compact trajectory modeling for tied linear transformations. An alternative noise condition dependent (CD) training algorithm is also proposed to handle the bias to training noise condition distribution. Consistent error rate gains were obtained over conventional VP-HMM mean and variance only trajectory modeling on a media vocabulary Mandarin Chinese in-car navigation command recognition task.

关键词： non-stationary noise generalized variable parameter HMM noise robust speech recognition

Thermoelastic properties of sandwich materials with pin-reinforced foam cores

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2008年第12期51卷 2059-2074页

作者： LU TianJian1.LIU Tao2,3 & DENG ziChen2,4 1.MOE Key Laboratory of Strength and Vibration,School of Aerospace,Xi’an Jiaotong university,Xi’an 71.049,China 2 {1. of Engineering Mechanics,Northwestern Polytechnical university,Xi’an 71.072,China 3 {1. of Engineering,university of cambridge,cambridge cb2 1.z,uk 4 State Key Laboratory of Structural Analysis of Industrial Equipment,Dalian university of Technology,Dalian 1.6024,China MOE Key Laboratory of Strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an 710049 China department of Engineering Mechanics Northwestern Polytechnical University Xi’an 710072 China department of Engineering University of Cambridge Cambridge CB2 1PZ UK State Key Laboratory of Structural Analysis of Industrial Equipment Dalian University of Technology Dalian 116024 China

Pin-reinforced foam is a novel type of sandwich core materials formed by inserting pins(trusses) into a foam matrix to create a truss-like network reinforced foam *** loading,the pins deform predominantly by local stretching whilst the deformation of foam is governed by local *** paper presents a theoretical study on the thermoelasticity of pin-reinforced foam sandwich *** calculate the effective thermoelastic properties of pin-reinforced foam cores,the energy-based homogenization approach is employed to develop a micromechanics-based model,calibrated by the existing experimental *** is found that the stiffness of the sandwich core is mainly governed by pin reinforcements:the foam matrix contributes little to sandwich *** with traditional foam cores without pin reinforcements,the changes in inplane thermal expansion coefficients are not vigorous as a result of pin reinforcements,while the through-thickness thermal expansion coefficient changes *** is also demonstrated that it is possible to design materials with zero or negative thermal expansion coefficients under such a context.

关键词： sandwich panel pin reinforcement analytical solutions homogenization thermoelasticity thermal expansion

Recent Advance in the Electrochemical Detection of Sulphide and Sulphhydryl Species

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2002年第2期18卷 161-168页

作者： Nathan S. Lawrence 1. Timothy G. J. Jones 2, Richard G. Compton 1.and Li Jiang 2 1. Physical and Theoretical Chemistry Laboratory, university of Oxford, Oxford, OX1.3Qz, {1. 2. Schlumberger cambridge Research, High Cross, Madingley Road, cambridge, Univ Oxford Phys & Theoret Chem Lab Oxford OX1 3QZ England Schlumberger cambridge Res Ltd Cambridge CB3 0EL England

This article aims at providing a critical review of some most recent developments in the electrochemical detection and measurement of hydrogen sulphide and the related species, which are of great significance to a variety of industries and in environmental moitoring. The molecular recognition processes are initiated by using either an organic precursor or a catalytic complex, leading to extensive ranges of detection. A series of advanced chemical and simulation techniques are used to probe the mechanistic details of the analytical chemistry involved.

关键词： Advance, Electrochemical detection, Sulphide Sulphhydryl

THE EFFECT OF LESSER HIMALAYAN CALC-SILICATES ON THE ^(87)Sr/^(86)Sr OF THE BHOTE KOSI RIVER OF NEPAL—IMPLICATIONS FOR HIMALAYAN WEATHERING, THE MARINE ^(87)Sr/^(86)Sr RECORD AND GLOBAL CLIMATE

在线全文

学校读者我要写书评

暂无评论

地学前缘 2000年第S1期7卷 396-397页

作者： Lee Oliver 1.Nigel Harris 1. Nancy Dise 1.Mike Bickle 2[WT5,5”BX](1.department of Earth Sciences, Open {1., Milton Keynes MK7 6AA, uk 2 department of Earth Sciences, cambridge {1., cambridge cb2 3EQ, uk)

During the last 40Ma the marine 87 Sr/ 86 Sr record shows a rapid rise (from 0 7078 to 0 7092) [1. , a trend which has been linked to the Himalayan Orogeny [2] . Indeed, many Himalayan rivers, principally those of the Ganges\|Brahmaputra system, display high 87 Sr/ 86 Sr relative to [Sr] [3] . Theories concerning the cause of this radiogenic Sr enrichment are diverse, but our results suggest that Lesser Himalayan carbonate\|rich lithologies play a vital role [4,5] .The Bhote Kosi originates in Tibet at ca.5km elevation from Tibetan Sedimentary Series (TSS) bedrock, before traversing the High Himalayan Crystalline Series (HHCS) and Lesser Himalaya (LH) of eastern Nepal, joining the Indrawati (at ca.0 6km elevation) to form the Sun Kosi, part of the Ganges system. Carbonates, calc\|silicates and silicates have been identified from the TSS, HHCS and LH, and the Bhote Kosi provides an opportunity to study the influence of these upon fluvial chemistry. Interest is focused on the cause of a rapid rise in riverine Sr\|isotope ratios immediately downstream of the Main Central Thrust (MCT) and the role of carbonate\|rich lithologies exposed in this section. Similar lithologies are lacking in the catchment of a second Nepalese river system, the Lantang Khola—Trisuli, sampled during the same period, and used as a baseline indicator for the effect of LH carbonates on the dissolved load of the Bhote Kosi.

关键词： weathering strontium isotopes Himalayan rivers carbonates

A MAGNUS EXPANSION FOR THE EQUATION Y'= AY - YB

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2001年第1期19卷 15-26页

作者： Arieh Iserles (department of Applied Mathematics and Theoretical Physics, {1., Silver Street, cambridge cb3 9EW, England) university of cambridge 英国 CB3 9EW

The subject matter of this paper is the representation of the solution of the linear differential equation Y = AY - YB, Y(0) = Yo, in the form y(t) = eΩ(t)Y0 and the representation of the function n as a generalization of the classical Magnus expansion. An immediate application is a new recursive algorithm for the deriVation of the Baker- Campbell-Hausdorff formula and its symmetric generalization.

关键词： Geometric integration Magnus expansions B aher- Campbell- Hausdorff formula.

CMC surfaces in the hyperbolic 3-space

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU zuhuan 1. 2 and LI zhenqi 1. 3 1. Institute of Mathematics, Fudan university, Shanghai 200433, China 2. {1. of Mathematics,Sichuan Union university, Chengdu 61.064, China 3. {1. of Mathematics, Nanchang university, Nanchang 33 nstitute of Mathemalics Fudan University Shanghai China department of Mathematics Sichuan Union University Chengdu China department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1.are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

A COMPREHENSIVE INVESTIGATION ON A PECULIAR DEFECT IN WURTzITE GaN FILM

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 1999年第4期12卷 327-333页

作者： S.Q.Wang1.,2) and H.Q.Ye1. 1. Laboratory of Atomic Imaging of Solids,Institute of Metal Research , The Chinese Academy of Sciences, Shenyang 1.001. ,China 2)department of Materials Science and Metallurgy , {1., cambridge cb2 3Qz, uk

Apeculiar crystal defect was observed by experiment of high resolution electron microscopy( HREM) .It wasidentifiedtoformed bytwothreading dislocationsand asegmentof(1. 20) domain boundary. An atomicstructure model was proposed for the anomalous defect. Theresultofthe weak beam experimentofelectron microscopeaffirmedthesuggested *** GaN(1. 2 0) domain boundaries werestudied by Molec ular Dynamicscalculations. Thetheoreticalresultsshowedthatthelike atom bonding domain boundary, whichcomposesthe main partofthe peculiar defect, has much higher formationenergy than itcounterpartof unlike atom bonding domain boundary. Theoutcome providesanotherevidenceforthesuggested model.

关键词： HREM weak beam electron microscopy crystal defect Wurtzite GaN molecular dynamics

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2005年第9期48卷 1245-1259页

作者： zHANG Xiaoxia~(1.2) & GUO Maozheng~(1.3) 1. School of Mathematical Sciences,Peking university,Beijing 1.0871.China 2. {1. of Mathematics,Yantai university,Yantai 264005,China 3. LMAM,Peking university,Beijing 1.0871.China 1. School of Mathematical Sciences Peking University 100871 Beijing China 2. department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

Parabolic equation of the m-Laplacian with nonlinear boundary condition

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第11期43卷 905-908页

作者： WANG Shu+ 1. 2, WANG Mingxin 3, XIE Chunhong 1.1. department of Mathematics, Nanjing {1., Nanjing 21.093, China 2. department of Mathematics, Henan {1., Kaifeng 475001. China 3. department of Applied Mathematics, Southeast {1., department of Mathernntics Nanjing University Nanjing China department of Mathematics Henan University Kaifeng China department of Applied Mathematics Southeast University Nanjing China

The existence and nonexistence of global positive weak solutions of parabolic equation of the m-Laplician with nonlinear boundary condition are dealt with. The necessary and sufficient conditions on the existence of a... 详细信息

关键词： nonlinear boundary condition parabolic equation of m-Laplacian global solution blow-up.