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Modeling and Numerical Investigation of the Inlet Circumferential Fluctuationsof Swept and Bowed Blades

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Journal of Thermal Science 2017年第1期26卷 1-10页

作者： TANG Mingzhi JIN Donghai gui Xingmin Aeroengine Numerical Simulation Research Center Beihang University Beijing China.

The circumferential fluctuation (CF) source terms induced by the inviscid blade force can affect the inlet distribution of flow parameters and radial equilibrium of swept and bowed blades. However, these phenomena cannot be adequately described by throughflow methods based on the axisymmetric assumption. A transport model for the CF stresses is proposed and correlated to the distribution of circulation to reflect the effect of the inviscid blade force. To investigate the effect of the inlet CFs on swept and bowed blades, the model is integrated into a throughflow model and applied to a series of cascades with different sweep and bow angles. For swept cascades, the CF source terms change the distributions of incidence angles, as well as the radial equilibrium at the inlet of the blade passage. And the influence is enhanced as the absolute value of the sweep angle increases. For bowed cascades, the distributions of incidence angles are also altered. For both cases, the model can offer a good prediction of the inlet CF source terms, and prove to exert a better prediction of blade design key parameters such as flow angles. © 2017, Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag Berlin Heidelberg.

关键词： Condensed matter physics

DESIGN AND IMPLEMENTATION OF COMPLETELY AUTOMATIC AND CONTINUAL PRODUCTION LINE FOR WATER-IN-OIL(W/O) EMULSION EXPLOSIVE

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中国有色金属学会会刊：英文版 1999年第2期9卷 201-207页

作者： He, Jianjun Yu, Shouyi gui, Weihua Central South Univ of Technology Changsha China

１ＩＮＴＲＯＤＵＣＴＩＯＮＥｘｐｌｏｓｉｖｅｉｓｏｎｅｏｆｔｈｅｔｒｅｍｅｎｄｏｕｓｅｎｅｒｇｙｒｅｓｏｕｒｃｅｓｗｈｉｃｈｐｅｏｐｌｅｏｆｔｅｎｕｔｉｌｉｚｅ．Ｉｔｉｓｎｏｔｏｎｌｙｕｓｅｄｉｎｍｉｌｉｔａｒｙｐ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＥｘｐｌｏｓｉｖｅｉｓｏｎｅｏｆｔｈｅｔｒｅｍｅｎｄｏｕｓｅｎｅｒｇｙｒｅｓｏｕｒｃｅｓｗｈｉｃｈｐｅｏｐｌｅｏｆｔｅｎｕｔｉｌｉｚｅ．Ｉｔｉｓｎｏｔｏｎｌｙｕｓｅｄｉｎｍｉｌｉｔａｒｙｐｕｒｐｏｓｅｓ，ｂｕｔａｌｓｏｕｓ...

关键词： W/O emulsion explosiveautomatic adjusting charge ratioautomatic charge mixingautomatic adjusting output

Sorption of 1-naphthol by plant cuticular fractions

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Journal of Environmental Sciences 2007年第10期19卷 1214-1220页

作者： CHEN Bao-liang LI Yun-gui Department of Environmental Science Zhejiang University Hangzhou 310028 China

The contribution of aliphatic-rich plant biopolymer to sorption of hydrophobic organic compounds is significantly important because of their preservation and accumulation in the soil environment, but sorption mechanism is still not fully understood. In this study, sorption of 1-naphthol by plant cuticular fractions was examined to better understand the contributions of respective fraction. Toward this end, cuticular materials were isolated from the fruits of tomato by chemical method. The tomato cuticle sheet consisted of waxes （6.5 wt%）, cuticular monomer （69.5 wt%）, and polysaccharide （24.0 wt%）. Isotherms of 1-naphthol to the cuticular fractions were nonlinear （N value （0.82 - 0.90）） at the whole tested concentration ranges. The K∞/Kow ratios for bulk cuticle （TC1）, dewaxed cuticle （TC2）, cutin （TC4）, and desugared cuticle （TC5） were larger than unity, suggested that tomato bulk cuticle and cutin are much powerful sorption medium. Sorption capability of cutin （TC4） was 2.4 times higher than the nonsaponifiable fraction （TC3）. The 1-naphthol interactions with tomato cuticular materials were governed by both hydrophobic-type interactions and polar （H-bonding） interactions. Removal of the wax and polysaccharide materials from the bulk tomato cuticle caused a significant increase in the sorption ability of the cuticular material. There was a linear negative trend between K∞ values and the amount of polysaccharides or fraction＇s polarities （（N＋O）/C）; while a linear positive relationship between K∞ values and the content ofcutin monomer （linear R^2 = 0.993） was observed for present in the cuticular fractions. Predominant sorbent of the hydrophobic organic compounds （HOCs） in the plant cuticular fraction was the cutin monomer, contributing to 91.7% of the total sorption of tomato bulk cuticle.

关键词： plant cuticle 1-naphthol sorption cutin monomer

Perceptual importance analysis for H.264/AVC bit allocation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 225-231页

作者： gui-xu LIN Shi-bao ZHENG Institute of lmage Comm. ＆ Info. Processing Dept. of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China Shanghai Key Laboratory of Digital Media Processing and Transmissions Shanghai Jiao Tong University Shanghai 200240 China

The existing H.264/AVC rate control schemes rarely include the perceptual *** a result,the im-provements in visual quality are hardly comparable to those in peak signal-to-noise ratio(PSNR).In this paper,we propose a perceptual importance analysis scheme to accurately abstract the spatial and temporal perceptual characteristics of video *** we perform bit allocation at macroblock(MB)level by adopting a perceptual mode decision scheme,which adaptively updates the Lagrangian multiplier for mode decision according to the perceptual importance of each *** results show that the proposed scheme can efficiently reduce bit rates without visual quality degradation.

关键词： Visual quality Human visual system Rate control H.264/AVC

Doped-TiO_2 Photocatalysts and Synthesis Methods to Prepare TiO_2 Films

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Journal of Materials Science & Technology 2008年第5期24卷 675-689页

作者： Ying gui Hao DU Lishi WEN Division of Surface Engineering of Materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences： Beijing 100039 China

TiO2 is a promising photocatalyst. However, the low photocatalytic efficiency calls for the modification of TiO2. Metal- and nonmetal-doping of TiO2 have been proved to be effective ways to enhance photocatalytic properties. This review provides a deep insight into the understanding of the metal- and nonmetal-doped TiO2 photocatalysts. This article begins with the introduction of the crystal structures of TiO2 and applications of TiO2 materials. We then reviewed the doped-TiO2 system in two categories：（1） metal-doped TiO2 photocatalysts system, and （2） nonmetal-doped TiO2 photocatalysts system. Both experimental results and theoretical analyses are elaborated in this section. In the following part, for the advantages of TiO2 thin films over particles, various preparation methods to obtain TiO2 thin films are briefly discussed. Finally, this review ends with a concise conclusion and outlook of new trends in the development of TiO2-based photocatalysts.

关键词： TiO2 films Photocatalysis Metal-doping Nonmetal-doping DFT

Numerical design optimization of compressor blade based on ADOP

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航空动力学报 2007年第11期22卷 1903-1908页

作者： JIN Dong-hai gui Xing-min School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100083 China

An aerodynamic design optimization platform(ADOP) has been *** numerical optimization method is based on genetic algorithm(GA),Pareto ranking and fitness sharing *** platform was used for design optimization of the stator of an advanced transonic stage to seek high adiabatic *** compressor stage efficiency is increased by 0.502% at optimal point and the stall margin is enlarged by nearly 1.0% at design rotating *** flow fields of the transonic stage were simulated with FINE/Turbo software *** optimization result indicates that the optimization platform is effective in 3D numerical design optimization problems.

关键词：最优化设计压缩机桨片空气动力学 ADOP 遗传算法

Investigation of Non-Axisymmetric Endwall Contouring in a Compressor Cascade

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Journal of Thermal Science 2017年第6期26卷 490-503页

作者： LIU Xiwu JIN Donghai gui Xingmin School of Energy and Power Engineering Beihang University Beijing 100191 China Co-innovation Center for Advanced Aero-engine Beijing 100191 China

The current paper presents experimental and computational results to assess the effectiveness of non-axisymmetric endwall contouring in a compressor linear cascade. The endwaU was designed by an endwall design optimi- zation platform at 0° incidence （design condition）. The optimization method is based on a genetic algorithm. The design objective was to minimize the total pressure losses. The experiments were carried out in a compressor cascade at a low-speed test facility with a Mach number of 0.15. Four nominal inlet flow angles were chosen to test the performance of non-axisymmetric Contoured Endwall （CEW）. A five-hole pressure probe with a head diameter of 2 mm was used to traverse the downstream flow fields of the flat-endwall （FEW） and CEW cascades. Both the measured and predicted results indicated that the implementation of CEW results in smaller comer stall, and reduction of total pressure losses. The CEW gets 15.6% total pressure loss coefficient reduction at design condition, and 22.6% at off-design condition （＋7° incidence）. And the mechanism of the improvement of CEW based on both measured and calculated results is that the adverse pressure gradient （APG） has been reduced through the groove configuration near the leading edge （LE） of the suction surface （SS）.

关键词： Non-axisymmetric endwall contouring, Compressor cascade, Corner separation, Wind tunnel experiments Optimization

Delay-dependent decentralized H_∞ filtering for uncertain interconnected systems

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Journal of Systems Engineering and Electronics 2008年第4期19卷 766-774页

作者： Chen Ning gui Weihua Zhang Xiaofeng School of Information Science and Engineering Central South Univ. Changsha 410083 P. R. China

This article considers delay dependent decentralized H∞ filtering for a class of uncertain interconnected systems, where the uncertainties are assumed to be time varying and satisfy the norm-bounded conditions. First, combining the Lyapunov-Krasovskii functional approach and the delay integral inequality of matrices, a sufficient condition of the existence of the robust decentralized H∞ filter is derived, which makes the error systems asymptotically stable and satisfies the H∞ norm of the transfer function from noise input to error output less than the specified up-bound on the basis of the form of uncertainties. Then, the above sufficient condition is transformed to a system of easily solvable LMIs via a series of equivalent transformation. Finally, the numerical simulation shows the efficiency of the main results.

关键词： interconnected systems H∞ filtering delay-dependent LMI.

Local controllability and stabilization of spacecraft attitude by two single-gimbal control moment gyros

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Chinese Journal of Aeronautics 2013年第5期26卷 1218-1226页

作者： gui Haichao Jin Lei Xu Shijie School of Astronautics Beihang University

The attitude control problem of a spacecraft underactuated by two single-gimbal control moment gyros （SGCMGs） is investigated. Small-time local controllability （STLC） of the attitude dynamics of the spacecraft-SGCMGs system is analyzed via nonlinear controllability theory. The conditions that guarantee STLC of the spacecraft attitude by two non-coaxial SGCMGs are obtained with the momentum of the SGCMGs as inputs, implying that the spacecraft attitude is STLC when the total angular momentum of the whole system is zero. Moreover, our results indi- cate that under the zero-momentum restriction, full attitude stabilization is possible for a spacecraft using two non-coaxial SGCMGs. For the case of two coaxial SGCMGs, the STLC property of the spacecraft cannot be determined. In this case, an improvement to the previous full attitude stabilizing control law, which requires zero-momentum presumption, is proposed to account for the singu- larity of SGCMGs and enhance the steady state performance. Numerical simulation results demonstrate the effectiveness and advantages of the new control law.

关键词： Attitude control Single-gimbal control moment gyro Singularity Small-time local controllability Underactuated spacecraft