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Relay node selection and combination ratio for amplify-and-forward OFDM-UWB communication

The Journal of China Universities of Posts and Telecommunications 2015年第3期22卷 41-48页

作者： Guo yong huang Liang School of Electronics and Information Engineering Beijing Jiaotong University

Due to its large bandwidth and the complexity of indoor environment, the ultra-wideband （UWB） channel is frequency selective, which affects the data rate and reliability of UWB communication. This paper investigates amplify-and-forward （AF） relay scheme to mitigate this reliability problem for orthogonal frequency division multiplexing （OFDM）-UWB communication. The relay can be used to acquire capacity gain and diversity gain just like multiple-input and multiple-output （MIMO） system. The first investigation focuses on the relay-node selection criterion and combination ratio for capacity gain. Capacity gain depends on the correlation of frequency responses between direct link and relay link in addition to signal-to-noise ratio （SNR） of relay link. Increased similarity of the two frequency responses increases capacity gain. Capacity gain＇s best relay and combination ratio are found by taking the derivative of the capacity equation. Solution of the quadratic derivative equation of ratio finds the optimal ratios for every potential relay node. The second investigation focuses on relay-node selection criterion and combination ratio for diversity gain. Higher diversity gain corresponds to less deep-faded sub-channels of combined signal. Reduced computation divides the problem into two steps： the first step selects the relay node according to the criterion that is dependent on the expectation value and variance of S（f）--the function of SNR of Jq the second step solves the optimization problem for optimal combination ratio. Numerical simulation shows that our scheme is effective in pursuit of capacity gain and of diversity gain.

关键词： cooperative system amplify-and-forward relay selection combination ratio OFDM Ultra-wideband communication

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Stochastic stability of viscoelastic system under non-Gaussian colored noise excitation

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Science China(Physics,Mechanics & Astronomy) 2012年第3期55卷 483-492页

作者： yong huang XianBin Liu Nanjing Univ Aeronaut & Astronaut State Key Lab Mech & Control Mech Struct Nanjing 210016 Jiangsu Peoples R China

This article examines a viscoelastic plate that is driven parametrically by a non-Guassian colored noise,which is simplified to an Ornstein-Uhlenbeck process based on the approximation *** examine the moment stability property of the viscoelastic system,we use the stochastic averaging method,Girsanov theorem and Feynmann-Kac formula to derive the approximate analytic expansion of the moment Lyapunov ***,the Monte Carlo simulation results for the original system are given to check the accuracy of the approximate analytic *** the end of this paper,results are presented to show some quantitative pictures of the effects of the system parameters,noise parameters and viscoelastic parameters on the stability of the viscoelastic plate.

关键词： viscoelastic system the moment Lyapunov exponents non-Gaussian colored noise stochastic averaging method the Monte Carlo simulation

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A new free-living marine nematode species of Rhinema from the South China Sea

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Journal of Oceanology and Limnology 2020年第2期38卷 545-549页

作者： ZHAI Hongxiu huang Mian huang yong College of Life Sciences Liaocheng UniversityLiaocheng 252059China Department of Marine Organism Taxonomy and Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

A new free-living marine nematode species of the genus Rhinema belonging to the family Monoposthiidae was collected from marine sediments in the Qiongzhou Strait of the South China Sea,and it is described here as Rhinema longispicula *** new species is characterized by coarsely annulated cuticle with 12 longitudinal ridges(alae)marked as reversed *** first and second annuli broader and form a kind of a cephalic *** amphideal fovea circular,situated in the middle of the broad second annulus,not surrounded by dense *** cavity cylindrical with a large dorsal *** with a prominent anterior pharyngeal bulb and an elongated terminal *** spicules strongly curved,with cephalated proximal end and pointed distal *** boat-shaped,without apophysis.A long and blunt precloacal seta *** with two opposed,outstretched ovaries.

关键词： Rhinema longispicula sp.nov. free-living marine nematode taxonomy

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Locations of Sonic Points in Advection Dominated Accretion Flows Around Black Holes

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Chinese Physics Letters 1999年第4期16卷 310-312页

作者： YUAN Feng huang ke-liang Department of Astronomy Nanjing UniversityNanjing 210093 Department of Physics Nanjing Normal UniversityNanjing 210097

The global transonic solutions describing advection dominated accretion flows around black holes are obtained by directly integrating the set of differential equations from the sonic point inward to the horizon and *** results show that the sonic points can locate themselves at almost any radius,regardless of the viscous parameter a and polytropic indexγ.This result is greatly different with previous *** solutions with very different values of R_(s)from 4.3 to 300R_(g) and withγ=1.5,5/3 are given *** consistency between this result and that in inviscid flows is emphasized.

关键词： flows integrating radius

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An improved adaptive sampling and experiment design method for aerodynamic optimization

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Chinese Journal of Aeronautics 2015年第5期28卷 1391-1399页

作者： huang Jiangtao Gao Zhenghong Zhou Zhu Zhao ke Computational Aerodynamics Institute China Aerodynamics Research and Development Center National key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical University

Experiment design method is a key to construct a highly reliable surrogate model for numerical optimization in large-scale project. Within the method, the experimental design criterion directly affects the accuracy of the surrogate model and the optimization efficient. According to the shortcomings of the traditional experimental design, an improved adaptive sampling method is proposed in this paper. The surrogate model is firstly constructed by basic sparse samples. Then the supplementary sampling position is detected according to the specified criteria, which introduces the energy function and curvature sampling criteria based on radial basis function （RBF） network. Sampling detection criteria considers both the uniformity of sample distribution and the description of hypersurface curvature so as to significantly improve the prediction accuracy of the surrogate model with much less samples. For the surrogate model constructed with sparse samples, the sample uniformity is an important factor to the interpolation accuracy in the initial stage of adaptive sam- pling and surrogate model training. Along with the improvement of uniformity, the curvature description of objective function surface gradually becomes more important. In consideration of these issues, crowdness enhance function and root mean square error （RMSE） feedback function are introduced in C criterion expression. Thus, a new sampling method called RMSE and crowd- ness enhance （RCE） adaptive sampling is established. The validity of RCE adaptive sampling method is studied through typical test function firstly and then the airfoil/wing aerodynamic opti- mization design problem, which has high-dimensional design space. The results show that RCE adaptive sampling method not only reduces the requirement for the number of samples, but also effectively improves the prediction accuracy of the surrogate model, which has a broad prospects for applications.

关键词： Aerodynamic optimization Crowdness enhance function RBF model RCE adaptive sampfing RMSE feedback

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One new species of free-living marine nematodes (Enoplida,Anticomidae,Cephalanticoma) from the huanghai Sea

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Acta Oceanologica Sinica 2007年第3期26卷 84-89页

作者： huang yong ZHANG Zhinan College of Marine Life Sciences Ocean University of China Qingdao 266003 China College of Life Sciences Liaocheng University Liaocheng 252000 China

One new species of free-living marine nematodes Cephalanticomafilicaudata sp. nov. from the huanghai Sea, China is described and illustrated. Cephalanticomafilicaudata sp. nov. is characterized by well developed cephalic capsule, three teeth at the anterior of oesophagus, excretory pore opens posterior to cervical setae, only two cervical setae per file, body length longer than 5 200 μm, tail long and no ventral-lateral seta between the supplement and the cloacal opening. Types are deposited in the College of Marine Life Sciences, Ocean University of China.

关键词： marine nematode new species huanghai Sea

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Aerodynamic design optimization of nacelle/pylon position on an aircraft

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Chinese Journal of Aeronautics 2013年第4期26卷 850-857页

作者： Li Jing Gao Zhenghong huang Jiangtao Zhao ke National key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical University

The arbitrary space-shape free form deformation （FFD） method developed in this paper is based on non-uniform rational B-splines （NURBS） basis function and used for the integral parameterization of nacelle-pylon geometry. The multi-block structured grid deformation technique is established by Delaunay graph mapping method. The optimization objects of aerodynamic characteristics are evaluated by solving NavierStokes equations on the basis of multi-block structured grid. The advanced particle swarm optimization （PSO） is utilized as search algorithm, which com-bines the Kriging model as surrogate model during optimization. The optimization system is used for optimizing the nacelle location of DLR-F6 wing-body-pylon-nacelle. The results indicate that the aerodynamic interference between the parts is significantly reduced. The optimization design system established in this paper has extensive applications and engineering value.

关键词： Delaunay graph mapping Free form deformation (FFD) Kriging model Navier-Stokes equations Particle swarm optimization (PSO) Space-shape

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Paramonohystera weihaiensis ***.(Xyalidae,Nematoda) from the intertidal beach of the Yellow Sea, China

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Journal of Oceanology and Limnology 2019年第4期37卷 1403-1408页

作者： huang yong SUN Jing College of Life Sciences Liaocheng University Liaocheng 252059 China key Laboratory of Ecology and Biodiversity of Shandong Colleges and University Liaocheng 252059 China

A new species of free-living marine nematode of the genus Paramonohystera was described from the intertidal beach, Weihai. Paramonohystera weihaiensis sp. nov. is characterized by cervical region with a circle of long setae;tail sexual dimorphism, male tail angled dorsally with sharp narrowed of the body at the cloaca, female tail ordinary conico-cylindrical;spicules slender, 2.5 abd long;gubernaculum plate, enlarged distal end with two teeth, without apophysis;precloacal supplements absent;Four caudal gland cells obviously extended to tail. The new species differs from the other fourteen known valid congeners by the combination of its characteristics:a circle of long cervical setae, tail sexual dimorphism, spicules slender, 2.5 abd long, gubernaculum plate with a distal pair of teeth.

关键词： new species free-living marine nematode taxonomy

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Design and optimization of a novel electrically controlled high pressure fuel injection system for heavy fuel aircraft piston engine

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Chinese Journal of Aeronautics 2018年第9期31卷 1920-1928页

作者： ke ZHANG Xudong huang Zhifeng XIE Ming ZHOU School of Aerospace Engineering Tsinghua University

The heavy fuel compression ignition engines are widely equipped as aircraft piston engines. The fuel injection system is one of the key technologies that determines the performance of engine. One of the main challenges is to precisely control the injected fuel quantity and flow rate in the presence of pressure fluctuation. This challenge is even more serious for heavy fuel. An original design for electrically controlled high pressure fuel injection system called Multi-Pumppressure-reservoirs fuel injection System(MPS) was demonstrated to reduce the pressure fluctuation and help keep injection stable. MPS was compared with an ordinary high pressure Common Rail fuel injection System(CRS). This work established one-dimensional AMESim and mathematical models for both CRS and MPS to study the effect of different structures and geometric parameters on the pressure fluctuations. The calculations show that the average fuel pressure fluctuation of MPS can be reduced by 57% for the crankshaft speed of 1900 r/min, and the pressure fluctuation before injection reduced by 100%. It is concluded that the pressure performance of MPS is less sensitive to pressure reservoir volume than that of CRS, and there is an opportunity for further volume reduction.

关键词： Aircraft engines AMESim Common rail Fuel injection Mathematical models Pressure effects Structural design

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Robust design of NLF airfoils

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Chinese Journal of Aeronautics 2013年第2期26卷 309-318页

作者： Li Jing Gao Zhenghong huang Jiangtao Zhao ke National key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical University

A robust optimization design approach of natural laminar airfoils is developed in this paper. First, the non-uniform rational B-splines （NURBS） free form deformation method based on NURBS basis function is introduced to the airfoil parameterization. Second, aerodynamic characteristics are evaluated by solving Navier-Stokes equations, and theγ-Reθt transition model coupling with shear-stress transport （SST） turbulent model is introduced to simulate boundary layer transition. A numerical simulation of transition flow around NLF0416 airfoil is conducted to test the code. The comparison between numerical simulation results and wind tunnel test data approves the validity and applicability of the present transition model. Third, the optimization system is set up, which uses the separated particle swarm optimization （SPSO） as search algorithm and combines the Kriging models as surrogate model during optimization. The system is applied to carry out robust design about the uncertainty of lift coefficient and Mach number for NASA NLF-0115 airfoil. The data of optimized airfoil aerodynamic characteristics indicates that the optimized airfoil can maintain laminar flow stably in an uncertain range and has a wider range of low drag.

关键词： Free form deformation Transition model NLF airfoils Particle swarm optimization (PSO) Robust design Surrogate model

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