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音频制播系统中声学特性对广播电视覆盖效果的影响研究

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电声技术 2024年第7期48卷 46-48页

作者：祝武汉中国广电四川网络股份有限公司眉山市分公司四川眉山620000

随着广播电视技术的迅速发展,声学特性在音频制播系统中的重要性愈发凸显。通过理论分析与实验验证,探讨音频制播系统中声学特性对广播电视覆盖效果的影响。研究结果表明,信号强度和语音清晰度等声学参数对覆盖效果具有显著影响。

关键词：音频制播系统声学特性广播电视覆盖传播效果

The hypoxia signaling pathway and hypoxic adaptation in fishes

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Science China(Life Sciences) 2015年第2期58卷 148-155页

作者： XIAO wuhan Key Laboratory of Aquatic Biodiversity and Conservation Institute of Hydrobiology Chinese Academy of Sciences

The hypoxia signaling pathway is an evolutionarily conserved cellular signaling pathway present in animals ranging from Caenorhabditis elegans to *** pathway is crucial for oxygen homeostasis ***-inducible factors(HIF-1αand HIF-2α)are master regulators in the hypoxia signaling *** concentrations vary a lot in the aquatic *** deal with this,fishes have adapted and developed varying strategies for living in hypoxic *** into the strategies and mechanisms of hypoxia adaptation in fishes will allow us to understand fish speciation and breed hypoxia-tolerant fish species/*** review summarizes the process of the hypoxia signaling pathway and its regulation,as well as the mechanism of hypoxia adaptation in fishes.

关键词： hypoxia hypoxia-inducible factors PHDs pVHL FIH fish

A PRICE-SETTING NEWSVENDOR MODEL UNDER CVAR DECISION CRITERION WITH EMERGENCY PROCUREMENT

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 85-104页

作者： Minghui XU School of Economics and Management,wuhan University,wuhan 430072,China School of Economics and Management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

The construction of Markov processes in random environments and the equivalence theorems

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Science China Mathematics 2004年第4期47卷 481-496页

作者： HU DiheSchool of Mathematics and Statistics, wuhan University, wuhan 430072, China School of Mathematics and Statistics Wuhan University Wuhan China

In sec.1, we introduce several basic concepts such as random transition function, p-m process and Markov process in random environment and give some examples to construct a random transition function from a non-homogeneous density function. In sec.2, we construct the Markov process in random enviromment and skew product Markov process by p - m process and investigate the properties of Markov process in random environment and the original process and environment process and skew product process. In sec. 3, we give several equivalence theorems on Markov process in random environment.

关键词： radom transition function, p -m process, Markov process in random environment, skew product Markov process, density function.

NEW WAVELET BASES FOR NON－HOMOGENEOUS SYMBOLIC SPACE OpS1,1^m AND RELATED KERNEL－DISTRIBUTION SPACES

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Chinese Annals of Mathematics,Series B 2002年第4期23卷 551-562页

作者： YANG QIXIANGDepartment of Mathematics, wuhan University, wuhan 430072, China. Department of Mathematics Wuhan University Wuhan 430072 China

This paper constructs several classes of new wavelet bases, which are unconditional bases for related operator spaces. Using these bases, the author analyzes non-homogeneous symbolic space OpSm1,1 and two related kernel-distribution spaces, and characterizes them in two wavelet coefficients spaces. Besides, some properties for singular integral operators are studied.

关键词： Wavelet bases Symbolic spaces Kernel-distribution spaces

LARGE DEVIATIONS FOR STATIONARY Φ-MIXING SEQUENCES IN τ-TOPOLOGY

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 149-158页

作者： Hu YIJUN Department of Mathematics, wuhan University, wuhan 430072, China. Department of Mathematics Wuhan University Wuhan 430072 China

The results of Bryc on large deviations for empirical measures of stationary Φ-mixing sequences are extended. Bryc states his results in the usual weak topology on the space ofprobability measures. In this paper, under somewhat weaker assumptions than those of Bryc,the author extends Bryc's results by taking the finer topology which is generated by the integralsover bounded measurable functions.

关键词： Large deviation Empirical measure Stationary sequence Φ-mixing τ-topology

ALMOST SURE AND QUASI-SURE GROWTH OF DIRICHLET SERIES

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Chinese Annals of Mathematics,Series B 1996年第3期17卷 343-348页

作者： YU JIARONG(Department of Mathematics, wuhan Uniyersity, wuhan 430072, China.) Department of Mathematics Wuhan University Wuhan 430072 China

For a given Dirichlet series absolutely convergent and of order (R)p∈(o, +) in the right-halfplan, its terms can be multiplied respectively by the members of a suitable sequence defined ina probability or topological space such that the series obtained is of order (R)ρ on any one ofcountably infinite horizontal haif lines almost or quasi surely.

关键词： Dirichlet series Almost sure growth Quasi-sure growth

SILYLATION OF CELLULOSE WITH TRICHLOROSILANE AND TRIETHOXYSILANE IN HOMOGENEOUS LiCl/N,N-DIMETHYLACETAMIDE SOLUTION

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Chinese Journal of Polymer Science 2000年第2期18卷 161-168页

作者： Hai-qing Liu Li-na Zhang Department of Chemistry, wuhan University, wuhan 430072, China 武汉大学湖北武汉

Silyl celluloses (SiC) were prepared by reacting cellulose with chloropropyltrichlorosilane (CPTCSi) and chloropropyltriethoxysilane (CPTESi) in LiCl/N,N-dimethylacetamide (DMAc). The Si content in the silyl cellulose could be controlled by adjustment of the molar ratio of silane and cellulose. FT-IR spectra showed that cellulose was readily reacted with the above two silane reagents, and the reactivity of CPTCSi is higher than that of CPTESi. It was presumed that the reaction process belongs to graft-polymerization. The results of differential thermal analysis (DTA) indicated that the thermostability of the materials produced increased with the increase of Si content in the sample. The acid resistance of the samples SiC in 1 mol/L HCl aqueous solution was improved significantly. When Si content was ca. 20%, the silyl cellulose has excellent thermostability, hydrophobicity, low density and stability in 1 mol/L HCl aqueous solution, owing to crosslinking of cellulose chain with silane.

关键词： sily cellulose chloropropyltrichlorosilane chloropropyltriethoxysilane LiCl/DMAc thermostability crosslinking

A RAISED PANEL METHOD BASED ON NURBS FOR FREE-SURFACE POTENTIAL FLOWS WITH FORWARD SPEED

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Journal of Hydrodynamics 2003年第2期15卷 112-120页

作者： Gao Gao, Ma LingSchool of Transportion, wuhan University of Technology, wuhan 430063, China Sch. of Transp. Wuhan Univ. of Technol. Wuhan 430063 China

A raised panel method based on NURBS (Non-Uniform Rational B-Splines) forfree-surface flows with forward speed is presented. In this generalized panel method, NURBS areemployed to represent the body geometry, disturbed free surface, and to express the unknown sourcestrength distribution, on the body surface and above the free surface. Compared with commonhigher-order panel methods, it has no need of adopting local coordinates. NURBS make the geometryrepresentation of the body shape and the wave pattern more precise. Raised panels above the freesurface produce less numerical dispersion error, need less CPU consumption and are helpful andcombined with collocation-point shifting up-stream, can satisfy the radiation condition *** using continuous and discrete Fourier analysis, numerical errors of this method are discussedand a general expression for the errors of numerical damping and dispersion, including the effectsof the vertical distance of singularities to the free surface, the order of singularity distributionrepresented by B-splines in panels, and collocation-point shifting is derived.

关键词： NURBS free-surface flow raised panel method error analysis B-spline