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Achievable bit rates of cognitive user with Vandermonde precoder in cognitive radio network

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Science china.Information Sciences) 2011年第7期54卷 1471-1480页

作者： XU XiaoRong 1,ZHANG JianWu 1 & ZHENG BaoYu 2 1 College of Telecommunication Engineering,hangzhou dianzi university,hangzhou 310018,china.2 Institute of Signal Processing and Transmission,Nanjing university of Posts and Telecommunications,Nanjing 210003,china 1. College of Telecommunication Engineering Hangzhou Dianzi University Hangzhou 310018 China2. Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China

In cognitive radio network (CRN) where primary user (PU) and secondary user (SU) wish to communicate with their corresponding receivers simultaneously over frequency selective fading channels,the interference between PU and SU should be eliminated in order to realize spectrum *** division multiple access (PDMA) that implements Vandermonde precoder in cognitive orthogonal frequency division multiplexing (OFDM) is proposed,which benefits from the frequency selectivity of the cognitive channel to form a frequency *** precoder enables SUs to achieve higher bit rate with optimal power allocation strategy under the condition of PU interference *** and simulation results are presented to prove theoretical *** is shown that,achievable bit rates (ABR) of SU could be achieved with optimal power allocation scheme in ***,it is also verified that,with Vandermonde precoder to form PDMA,SU’s signal-to-noise ratio (SNR) and the target rate of PU could impact the ABR of SU significantly in CRN.

关键词： achievable bit rates (ABR) Vandermonde precoder precoder division multiple access (PDMA) optimal power allocation cognitive radio network (CRN)

TRIPLE　INTERACTIONS　OF　CONORMAL　WAVES　FOR　HIGHER　ORDER　SEMILINEAR　HYPERBOLIC　EQUMIONS

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Chinese Annals of mathematics,Series B 1995年第1期16卷 23-32页

作者： FANG DAOYUAN (Center for Mathematical Sciences, Zhejiang university, hangzhou 310027, china.) 浙江大学数学科学中心浙江杭州

The interaction of three conormal waves for semi-linear strictly hyperbolic equations of third order is considered. Let Σi, i = 1, 2, 3, be smooth characteristic surfaces for P= Da(D_t￣2 -△) intersecting transversally at the origin. Suppose that the solution u to Pu = f(t, x ,y)D u), ≤2 is conormal to Σi, i = 1, 2, 3, for t < 0. The author uses Bony's second microlocajization techniques and commutator arguments to conclude that the new singularities a short time after the triple interaction lie on the surface of the light cone Γ over the origin plus the surfaces obtained by flow-outs of the lines of intersection Γ ∩ Σi and Σi∩ Σj, i, j = 1, 2, 3.

关键词： Hyperbolic equation Conormal wave Interaction Characteristic surface.

DIMENSIONS OF SELF-AFFINE SETS WITH OVERLAPS

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Chinese Annals of mathematics,Series B 2003年第3期24卷 275-284页

作者： HUA Su department of mathematics, Tsinghua university, Beijing 100084, china. Tsing Hua Univ Dept Math Beijing 100084 Peoples R China

The authora develop an algorithm to show that a class of self-affine sets with overlaps can be viewed as sofic affine-invariant sets without overlaps,thus by using the results of [11] and [10],the hausdorff and minkow... 详细信息

关键词： self-affine set overlap hausdorff dimension minkowski dimension

Mechanisms of granular activated carbon anaerobic fluidized-bed process for treating phenols wastewater

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Journal of Environmental Sciences 2002年第1期14卷 132-135页

作者： LAO Shan gen (department of Environmental Engineering, Zhejiang university, hangzhou 310029, china. department of Environmental Engineering Zhejiang University Hangzhou 310029

Granular activated carbon (GAC) anaerobic fluidized bed reactor was applied to treating phenols wastewater. When influent phenol concentration was 1000 mg/L, volume loadings of phenol and COD Cr were 0 39 kg/(m 3·d) and 0 98 kg/(m 3·d), their removal rates were 99 9% and 96 4% respectively. From analyzing above results, the main mechanisms of the process are that through fluidizing GAC, its adsorption is combined with biodegradation, both activities are brought into full play, and phenol in wastewater is effectively decomposed. Meanwhile problems concerning gas liquid separation and medium plugging are well solved.

关键词： granular activated carbon (GAC) anaerobic fluidized bed phenol removal rate

CLASSICAL SOLUTION OF QUASI-STATIONARY STEFAN PROBLEM

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Chinese Annals of mathematics,Series B 1996年第2期17卷 175-186页

作者： YI FAHUAI department of mathematics, Suzhou university, Suzhou 215006, china. SUZHOU UNIV DEPT MATHSUZHOU 215006PEOPLES R CHINA

This paper considers the quasi-stationary Stefan problem:△u(x,t)=0 in space-time domain,u=0 and Vv +(?)u/(?)u=0 on the free boundary.Under the natural conditions the existence of classical solution locally in time is proved bymaking use of the property of Frechet derivative operator and fixed point theorem. For thesake of simplicity only the one-phase problem is dealt with. In fact two-phase problem can bedealt with in a similar way with more complicated calculation.

关键词： Classical solution Quasi-stationary Stefan problem Frechet derivative

PARTICLE SIZE DISTRIBUTION IN A PLANAR JET FLOW UNDER-GOING SHEAR-INDUCED COAGULATION AND BREAKAGE

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Journal of Hydrodynamics 2010年第4期22卷 445-455页

作者： GAN Fu-jun LIN Jian-zhong YU Ming-zhou State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China china.Jiliang university Hangzhou 310018 China State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China china.Jiliang university Hangzhou 310018 China

A CFD simulation is performed for a particle-laden planar jet *** Reynolds number is 8300,and the initial particle diameter is 1 μ*** Eddy Simulation（LES） is employed to calculate the flow field,and the Taylor-series expansion moment method（TEMOM） is adopted to deal with the balance equation of particle coagulation and *** shear-induced coagulation kernel,power-law breakage kernel and symmetric fragment distribution function are *** prediction of the distribution of the mean streamwise velocity of the jet is in good agreement with experimental *** evolution of particle number concentration,volume concentration,polydispersity,particle diameter and standard geometric deviation is discussed in *** results show that as the jet travels downstream,the particle number concentration and volume concentration decrease,while their spans become *** polydispersity and particle diameter are very large in the shear layers at the upstream and in the core of vortex structures at the *** particle standard geometric deviation changes within the range of 1.32 ≤σg≤ 1.96,and increases sharply in the shear *** variables approach the steady-state as time progresses.

关键词： Taylor-series expansion moment method shear-induced coagulation breakage planar jet

LIMIT CYCLES AND BIFURCATION CURVES FOR THE QUADRATIC DIFFERENTIAL SYSTEM (III)_(m=0) HAVING THREE ANTI-SADDLES (I)

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Chinese Annals of mathematics,Series B 1996年第2期17卷 167-174页

作者： YE YANQIAN department of mathematics, Nanjing university, Nanjing 210008, china. 南京大学数学系江苏南京

For the quadratic system: x=-y+δx + lx2 + ny2, y=x(1+ax-y) under conditions -10 the author draws in the (a, ()) parameter plane the global bifurcationdiagram of trajectories around O(0,0). Notice that when na2+l < 0 ... 详细信息

关键词： Quadrtic systen Anti-saddle Bifurcation curve Limit cycle

THE GOLDBACH-VINOGRDOV THEOREM WITH THREE PRIMES IN A THIN SUBSET

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Chinese Annals of mathematics,Series B 1998年第4期19卷 479-488页

作者： LIU JIANYA (department of mathematics, Shandong university, Jinan 250100, china.) 山东大学数学系山东济南

It is proved constructively that there exists a thin subset S of primes, satisfying for some absolute constant c＞0, such that every sufficiently large odd integer N can beLet r be prime, and hi positive integers with (bj, r) = 1,j = 1, 2, 3. It is also proved that, for almost all prime moduli r＜ log- N, every sufficiently large odd integer N = b1 + b2 +ba(modr) can be represented as where c ＞ 0 is an absolute constant.

关键词： Goldbach-Vinogradov theorem Exponential sum Primes Arithmetic progression Mean-value theorem

Joint spatial registration and multi-target tracking using an extended PM-CPHD filter

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Science china.Information Sciences) 2012年第3期55卷 501-511页

作者： LIAN Feng1 , HAN ChongZhao1, LIU WeiFeng2, LIU Jing1 & YUAN XiangHui1 1SKLMSE Lab, MOE KLINNS Lab, School of Electronics and Information Engineering, Xi’an Jiaotong university, Xi’an 710049, china.2School of Automation, hangzhou dianzi university, hangzhou 310018, china 1. SKLMSE Lab MOE KLINNS Lab School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. School of Automation Hangzhou Dianzi University Hangzhou 310018 China

An extended product multi-sensor cardinalized probability hypothesis density (PM-CPHD) filter for spatial registration and multi-target tracking (MTT) is proposed. The number and states of targets and the biases of sensors are jointly estimated by this method without the data association. Monte Carlo (MC) simulation results show that the proposed method (i) outperforms, although computationally more expensive than, the extended multi-sensor PHD filter which has been proposed for joint spatial registration and MTT; (ii) outperforms the multi-sensor joint probabilistic data association (MSJPDA) filter which is also extended in this study for joint spatial registration and MTT when the clutter is relatively dense.

关键词： multi-sensor spatial registration multi-target tracking (MTT) cardinalized probability hypothesis density (PHD) filter random finite set (RFS)