Journal of Wuhan University of Technology

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Study on Blacknickel Solar Selective Absorbing Coatings

WANG Tao，YE Weiping，CHENG Xudong，HUANG Wei，MA Tao，WANG Hui

. 2011, (5): 1-5.

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The black nickel solar selective coating was prepared on the presilverplated
H85 copper alloy by plating method. The effect of plating time, current density
and bright silver bottomcoating’s presence or absence were studied on
the coating’s solar absorptance. This coating was characterized by surface SEM
&
EDS, XRD phase structure and the solar selectivity (α/ε) and a reasonable
p
rocess parameters of black nickel selective absorbing coating was proposed. The
result shows that the structure of the coating consists of NDiamond C, NiO, NiC
, NiZn3; the addition of the bright infrared reflection layer of silver got a sig
nificant improvement on the coating’s selectivity and finally a fine selective c
oating was obtained (α= 0.90,ε=0.06, α/ε=15).

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Preparation of Nanocrystalline Titanic Dioxide by Gelnetwork Precipitation Method and Photocatalytic Analysis

YAN Xin, ZHANG Qihuan, WU Jun, YAN Yuhua

. 2011, (5): 6-8.

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The nanocrystalline TiO2 was prepared by gelnetwork precipitation method based on the orthogonal experiments and the parameters that have an effect on the particle size of TiO2 nanoparticles were analyzed. The products were characterized using Xray diffraction (XRD) and scanning electron microscopy (SEM). The optimal parameters for preparing TiO2 nanoparticles were determined as: gelatin concentration 14%, aqua ammonia 0.8 mol/L and Ti3+ concentration 0.6 mol/L, respectively. The photocatalytic experiments showed that when catalyst reached 75 mg/L, c(TiO2)= 8 g/L and t=1 h, the nanometer TiO2 had highest efficiency, 84.17%, in decolourization.

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Effect of Eu3+ Concentration on Crystal Structure and Luminescence Properties of Ca3Al2O6:Eu3+

SHAO Jingchang, XUE Lihui

. 2011, (5): 9-13.

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Ca3Al2O6:Eu3+ phosphor was prepared via solution combustion synthesi
s
at 450 ℃ using a fuel mixture of urea and βalanine. It shows four major emiss
i
on peaks located at 594 nm，617 nm, 653 nm and 700 nm corresponding to 5D0→7Fj (
j=1～4) typical transitions of Eu3+ respectively. The strongest one appear
s at 61
7 nm which emits red light. Effect of Eu3+ doped concentration on crystal
struct
ure and luminescence properties of Ca3Al2O6:Eu3+ was studied. The re
sults show t
hat with the increasing of Eu3+ doped concentration the lattice parameters
decre
ase together with a blue shift of the Raman peak of the symmetric stretching vi
bration of ［O—Al—O］. The emission intensity increases gradually with the add
it
ion of Eu3+ up to the quenching concentration 6%, the quenching mechanism
is con
sidered to be the exchange interaction. The intensity ratio of 5D0→
7F2 to 5D0→7F1 increases following the enhanced Eu3+
doped concentration, which indicates tha
t the Eu3+ ions occupy more inversion symmetry sites of Ca2+ in Ca3Al2
O6:Eu3+.

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Effect of Ce3+and Yb3+ Ion on the Luminescence Properties of Er3+-doped Ga2O3-GeO2-Na2O Glass

SHI Dongmei，ZHAO Yinggang，WANG Xiaofeng

. 2011, (5): 14-17.

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This paper investigates thermal stability and spectroscopic properties of Er3+/Yb3+/Ce3+doped 15Ga2O375GeO210Na2O glasses〖JP〗. The influence of Yb3+ and Ce3+ on the 1.5μm and upconversion luminescence of Er3+ has been discussed. It is noted that introduction of the Yb3+ greatly improves 1.5μm and upconversion luminescence intensity due to the strong absorption of the glass for 980 nm pumping light. The introduction of Ce3+ significantly increases the 1.5μm luminescence and reduces the Er3+ upconversion luminescence. Optimization of the Yb2O3/CeO2 molar ratio is about  3∶1.

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Precipitation and Calcine Technology Research of TiO2 Materials

JIANG Feng, SHEN Leinuo, CHEN Xiaobo, XIAO Qing, XIANG Zhoudan

. 2011, (5): 18-21.

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High quality TiO2 nanomaterials were successively synthesized by liquid phase precipitation, using titanium pigment as raw material and NH4HCO3 as precipitator. The inference of calcination temperatures to phases, particle size and microstructure were studied. Research indicated that higher calcination temperature was, larger the particle size was. When calcination temperature was higher than 700 ℃, part of anatase changed into rutile; spherical TiO2 nanopowders with excellent microstructure performance and particle size about 10 nm was adopted when calcination temperature was 550 ℃.

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Influence of Mechanochemical Effect on Al-(O,OH) Polyhedron of Kaolinite

SI Peng, QIAO Xiuchen，YU Jianguo

. 2011, (5): 22-26.

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The influence of mechanochemical effect on Al(O,OH) polyhedron of kaolinite was investigated using Xray diffraction, infrared spectrum, magicanglespinning nuclear magnetic resonance, scanning electron microscope and hydrochloride acid leaching methods, compared with the thermal activation of kaolinite. The results showed that the Al(O,OH) octahedron of kaolinite was distorted gradually due to the mechanochemical effect, giving rise to an active substance with longrange disorder, in the simultaneous presence of 4, 5 and 6 coordinated Al. The AlVI in this substance was more abundant than that in metakaolinite, which was obtained through thermal activation. The mechanochemical effect also led to the dehydroxylation of Al(O,OH) octahedron of kaolinite, whereas part of the water involved in the structure of the active substance through coordination or hydrogen bond. The coordinated water was associated with Al, giving a new AlVI coordination of \[AlO5(H2O)\]. The activity of the AlVI in \[AlO5(H2O)\] was the same as the AlV in \[AlO5\], and higher than the AlVI of \[AlO6\] in metakaolinite.

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Molecular Dynamics Simulation on Stability Characteristics of Hydrogen Peroxide Hydrate

YAN Kefeng，WAN Lihua，LI Xiaosen

. 2011, (5): 27-32.

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In this work, the stability of structure I (SI) hydrate formatted by the object molecular, hydrogen peroxide(HP) is investigated using the molecular dynamics simulation. The mechanism of the SI hydrate stability is analyzed systematically with injecting different number HP into the cage of SI hydrate. The results illustrate that HP can not format SI hydrate without assistant gas. It has stabile effect to form SI hydrate with methane as assistant gas. The dissociation of SI hydrate is slow with increasing assistant gas. When one HP inject into big cage of SI hydrate with assistant gas, it can form SI hydrate. It is concluded HP has comparability with alcohol as inhibitors promoting the dissociation of hydrate, the stable hydrate structure can only formed in lower concentration, provided the important reference value for the experimental investigation into the promotion effect of HP on the hydrate dissociation.

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Numerical Simulation of Combustion Space in Floating Glass Furnace

FENG Minge,CHEN Guoping, LI Hui,YIN Hairong

. 2011, (5): 33-36.

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This paper selects a floating glass furnace by 93% oxygen and 97%CH4 ,whose pull rate is 400 t/d as simulate object. Divided Mesh used Gambit software, numerical calculation procedure used Fluent software. The temperature distribution of combustion space used nonpremixed preDPF combustion model, discrete ordinates standard model and k?? to solve. The results show that can be more accurate simulation changes of the glass surface temperature in this way; The importance of the research on the changes of water which influence on the quality of glass was analyzed.

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Effect of Chemical Additives on the Synthesis of Calcium Carbonate Whiskers

FENG Xiaoping，ZHANG Zhengwen，ZHAO Taotao，WU Zhaopeng

. 2011, (5): 37-40.

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Calcium carbonate whiskers were respectively synthesized by carbonation method using magnesium hydroxide and magnesium chloride as chemical additives. The morphology, phase composition and structure of the product were characterized by SEM and XRD. And effect of chemical additives on the synthesis of calcium carbonate whiskers was analyzed. The results indicate that magnesium hydroxide is easier than magnesium chloride to promote the growth of calcium carbonate whiskers. And the dendrite whiskers can be acquired when the ratio of magnesium and calcium involved in the reaction solution is less than 1, the temperature of reaction is 80 ℃, the agitation rate is 100～130 r/min and the flux of CO2 is 70～100 mL/min.

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Model and Numerical Analysis of Ions Migration in Concrete During the Process of Electrochemical Chloride Extraction

ZHU Pin, WANG Xinxiang, WEI Jiangxiong, ZHENG Liang, YU Qijun

. 2011, (5): 41-47.

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In this paper, the model of ions migration in concrete has established under the electric field. Na+, Cl- ions migration law was analyzed theoretically during the process of electrochemical chloride extraction(ECE) based on the experimental parameters, empirical constants and suitable boundary conditions. The content of Na+ and Cl- ions in concrete after ECE is agree with simulating results, which shows the model of this paper is effective and reasonable. Both experimental results and simulating results indicate that distribution profile of Cl- ions in the radial direction is the convex curve under electric field, and with the max value of Cl- content appears at a certain position in concrete. With growth of the treatment time, both Cl- ions content in concrete and extracted rate of Cl- ions decline, while Na+ ions gradually aggregates close to reinforcement.

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Extraction of Chemical Active Components and Evaluation of Cementitious Activity of Steel Slag

LI Zaibo, ZHAO Sanyin, ZHAO Xuguang, HE Tusheng

. 2011, (5): 48-53.

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There is greater difference among the cementitious activity of steel slag from different sources. To establish a rapid evaluation method of steel slag cementitious activity, dissolution experiments of steel slag chemical active components through evaporationcondensation method were carried out and the dissolution characteristics and mechanics was studied. The relationship between dissolution characteristics and cementitious activity was analyzed in combination with mortar strength. Results show that there exist significant differences amongst the amounts of chemical active dissoluted components. The dissolving process can be described by shrinking unreacted core model controlled by intrapaticle diffusion. The linear relationship between dissolution characteristics and cementitious behavior of steel slag is significant. Cementitious activity of steel slag from different sources can be evaluated rapidly by the dissolving quantity of (CaO+Al2O3) and SiO2.

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Effect of Different Factors on Frost Resistance of Recycled Aggregate Concrete

CHEN Deyu，LIU Laibao，YAN Yun，TAN Kefeng，LIU Huan

. 2011, (5): 54-58.

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The influence of modified and unmodified aggrega
te，silica fume and ai
rentraining agent on the frost resistance of C40 recycled aggregate concrete h
a
s been studied. The results show that the frost resistance of the recycled aggre
gate concrete with various replacement of recycled aggregate through 300 cycles
of freezing and thawing, compared to natural aggregate concrete (control concret
e). Moreover, the frost resistance of recycled aggregate concrete falls with th
e increase of the replacement of recycled aggregate. The frost resistance of re
cycled aggregate concrete can be improved through either addition of the modifie
d recycled aggregate by organicsilicon or an appropriate amount of silica fume
or entrained air agent, and it can be attributed to the improvement of the micr
ostructure of recycled aggregate concrete. Silica fume and airentraining agent
can obviously improve the frost resistance of recycled aggregate concrete.

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PNGF Composites Regulated GAP43 and β-TubulinⅡ Genes Transcription in Rat Pheochromocytoma Cells

YU Chang, QIU Tong, YAN Qiongjiao, YIN Yixia, LI Shipu

. 2011, (5): 59-62.

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A novel nerve guidance conduit (NGC) was synthesized by embedding nerve growth factor (NGF) into a degradable RGDmodified composite (PRGD) to improve the peripheral nerve repair (PNGF). This study was to evaluate the responses of GAP43 and βTubulin Ⅱgenes mRNA expression when PC12 cells were exposed to the extract of PNGF films. RNA was isolated from PC12 cells cultured in vitro and gene expression were detected by realtime quantitative PCR at 1 d, 2 d and 3 d. Results indicated that the transcription of GAP43 and βTubulin Ⅱgenes were significantly upregulation in the extract of PNGF films and the peak were almost presented at the second day. Results show that the sustained released NGF promoted PC12 cells differentiation.

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Evaluation of the Bovine Hemoglobin Molecularly Imprinted Polymer Membrane by QCM

ZENG Tao, FANG Guijie, LIU Lijian, XIE Weihong

. 2011, (5): 63-67.

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By utilizing bovine hemoglobin as template，AIBN as photo initiator，TEGDMAMMA (TEGDMA as crosslinker and MMA as functional monomer) and TEGDMA molecularly imprinted polymer(MIP) menbranes were synthesized on the quartz crystal microbalance under the condition of UVirradiation，respectively，response signal of different membranes to template protein was characterized by quartz crystal microbalance(QCM)，and the capacity of two different MIP material membrane surfaces on the adsorption of bovine hemoglobin were compared. The results showed that MIPbased QCM biosensor exhibited excellent selective capacity in adsorbing bovine hemoglobin.

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Research on Evolutionary Design for Container Crane's Reinforced Structure

SU Li, HE Shan, ZHAO Zhangyan, XING Liang

. 2011, (5): 68-71.

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Through analysis the finite element data of portal container crane's r
einforced structure, the corresponding mathematical model is biult,takes the com
bination of structural weight and von mises stress as objective function,uses ge
netic algorithm,proceeds the genetic evolution operation,obtains optimal solutio
n of reinforced structural evolutionary design, achieves the lightest structure
weight and the lowest shipping cost,has profits from the optimization of other c
omplex largescale metal structure.

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Analysis of Structural Strength for the Zhenghe’s Treasure Ship

KU Yun，GONG Changqi

. 2011, (5): 72-76.

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According to the drawings of the recovery design for the Zhenghe’s treasure ship, and the scantling of various members in the ship’s structure, calculation models of all of the main structure of the ship were established for the 3dimensional finite element analysis of structural strength, mainly adopting solid elements respectively. The deformation and stress situation of the whole structure in the sea under the fullloaded case were directly computed and analyzed in order to assess the structural strength of the ship. Optimal calculations were also carried out with reduced thicknesses of plating in the ship’s structure. From the perspective of the hull structure strength to prove that the historical records of Zhenghe’s Baochuanscale importation is credible.

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Indirect Trefftzbased Approach of CouplingStructuralAcoustic

LI Zhijiang，CAO Ping，LI Peng

. 2011, (5): 77-80.

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This paper describes the basic concept of the technique for the modeling of the 3D coupled structural acoustic systems. According to the principle of indirect Trefftz method, structural and acoustic domains are approximated in terms of wave functions and particular solutions. The structural and acoustical boundary conditions are transformed into a weighted residual formulation. Solving model for the unknown wave function contributions and backsubstituting the results into the expansions yield the prediction of the dynamic response of the structural acoustic system. And numerical analysis is carried out by the software of SYSNOISE. The results are shown to be better convergence properties. The proposed method is a novel method for mid frequency vibration analysis.

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Applications of Continuous Pattern Recognition to Diagnostic Technology of Traffic Safety

ZHANG Jie, SUN Xiaoduan, HE Yulong, LIU Xiaoming

. 2011, (5): 81-85.

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In the course of investigating traffic safety threat the direct diagno
sis couldn't concentrate on convergences of crashes within the limited section,
so the boundary of a segment with abnormal crashes may not be captured accuratel
y. Continuous pattern recognition is a new screening method for traffic safety d
iagnosis. The segments with potential problems of traffic safety could be identi
fied by successive movement and scanning every interval. Steps and main points o
f analysis about the technology were given. Quantitative calculation of the abno
rmal extent of crash was studied. The technology is easy to operate with compute
r programming because of repeated calculation. It could judge the positions of t
raffic safety threats correctly, then countermeasures could be made and traffic
safety of the road would be improved.

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Study on New Mix Design Method for Balancing Antirutting and Anticracking

FENG Xinjun, ZHA Xudong, WANG Wenyuan, DU Yuefan

. 2011, (5): 86-89.

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Based on analyzing the deficiencies of Marshall mix design method, a new mix design method for balancing antirutting and anticracking was put forward. Authors determined the optimal OilStone Rate of AC13, SUP13, CAVF13, BLF13 with Marshall mix design method and new mix design method for balancing antirutting and anticracking separately. Then authors compared and appraised these design methods. The results show that the optimal OilStone Rate designed by new mix design method for balancing antirutting and anticracking is 0.1~0.3% smaller than that designed by Marshall mix design method. And the pavement performance of asphalt mixtures designed by new mix design method for balancing antirutting and anticracking is more in line with the requirements of climatic condition of the asphalt pavement engineering than that of asphalt mixtures designed by Marshall mix design method.

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Test Analysis on Shear Performance for Interlayer Bond of Base and Surface in Semirigid Base Pavement

ZHAO Guijuan

. 2011, (5): 90-94.

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Unit dosage of interlayer bond of base and surface will affect shear performance greatly. Based on direct shearing test，the paper completed shear performance comparison on four seal coats which included matrix asphalt and SBS modified bitumen bonded aggregate. The results showed that the best shear performance is provided by SBS modified bitumen+gravel.And according to the seal coat of SBS modified bitumen+gravel，the gravel of different partical size is compared，the results from indoor and outdoor tests show that the max shear stress is provided by 13.2～16.0 mm gravel and the value is 0.28 MPa.

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Aging Equation of SBS Modified Asphalt and Its Application

KANG Hongwei，TAN Xuezhang，JI Xiaoping

. 2011, (5): 95-99.

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This paper sets up a nonlinear differential aging equation of SBS modi
fied asphalt and explores the aging law of it with the help of nonlinear differe
ntial equation. The author of the paper has calculated the aging quantity and ra
te of the asphalt at the random time, measured the indexes of its penetration, d
uctility at 5 ℃, softening point and viscosity at 135 ℃ at different aging tim
e
in RTFOT, and obtained the aging parameters and equation of all the indexes. Thr
ough the analysis for the relativity between the tested values and the aging equ
ation values, the author proves the reliability of the nonlinear aging equation 
and examines the potential application of it. The research results show that the
nonlinear aging equation can predict the law of the penetration, ductility, sof
tening point and viscosity, and obtain the aging quantity and rate of all the in
dexes at the random time. The calculated results from the aging rate equation in
dicate that the aging rate of the asphalt shows its maximum value at the beginn
ing, but becomes smaller and smaller as the time going, which meets with the ever
yday performances. This aging equation can be used to assess the antiaging per
formances and durability of asphalt, predict pavement cracking and determine the
pavement regeneration.

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Research on Hydrodynamic Pressure of Void Under Concrete Pavement

LIAN Xiangdong，FU Qilin，CHEN Shuanfa，NIE Wulong，WANG Binggang

. 2011, (5): 100-103.

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Based on the results of hydrodynamic pressure simulation test, the paper evaluated the most unfavorable position of void under slab, and analyzed the effects of retting saturation, void area, load ,load position and load speed on the reduce of void under slab. Research shows that: the most unfavorable position of void under slab is on the slab corner; the hydrodynamic pressure will increase with the void area increasing; when its retting saturation is smaller than 60%, the hydrodynamic pressure increase slightly, and its retting saturation exceed 60%, the hydrodynamic pressure increase sharply; and it is effective to reduce hydrodynamic pressure by decreasing load speed.

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Chute System Research in Stone Transportation of Hazardous Rock Cutting

XIE Quanmin, WANG Hongbin, WU Yong

. 2011, (5): 104-107.

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Chute system is a kind of economic and safe mode of transportation in mountain exploitation. Although having realized its advantages, people study rarely about its theories. In particular, there aren’t related theories and standards in its designs. For this reason, the article studies about the form, velocity and flying distance of rock moving in chute system. And basing on this, taking Banyan Mountain hazardous rock cutting for example, the article discusses application of chute system. Chute system makes full use of the characteristic of large altitude difference. The fact shows that, it not only saves transportation cost, but also accelerates construction progress. Chute system has better spreading prospect and reference value.

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Design on Model Test of Shield Tunneling in Transparent Soil

SUN Jizhu，XIAO Wenhui

. 2011, (5): 108-112.

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In view of the inconvenience to obtain internal deformation of soil and other shortcomings in the existing shield model test, transparent soil is synthesized by means of calcium bromide solution and fused silica, the testing system of shield model is designed on this basis. Cutter head of shield machine model can be rotated, and also be retracted into the shield shell, and both are controlled with screw, this may be used to model shield tunneling and decreasing of support force at tunnel face. During shield tunneling the laser is used to illuminate the crosssection of transparent soil in front of the shield, the digital camera is used to capture the images continuously, internal soil deformations are calculated using particle image velocimetry. So the microscopic mechanism of tunneling induced soil deformation is visualized truly.

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Influenceof Input Ground Motion on Acceleration Magnification Factor of CFRD

ZHANG Fabao，DENG Haifeng

. 2011, (5): 113-116.

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The 3D dynamic finite element analysis is used for a concrete faced rockfill dam with equivalent viscoelastic model. The seismic dynamic response result of CFRD is obtained by calculating under different design intensity (peak acceleration 0.1g~0.4g). Results show that the dam's peak acceleration approximate linear increases with the increase of input ground motion, but magnification factor of peak acceleration reduces nonlinearly with the increase of input ground motion. In this paper, variation of seismic peak acceleration has some reference significance for seismic fortification of concrete face rockfill dam.

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Research on the Ultimat Bearing Capacity Analysis of XKKjoints by Finite Element Analysis

YANG Weiguo，WANG Yaofeng，GU Peng，LI Xingpo

. 2011, (5): 117-122.

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The elastoplastic finite element analysis (FEA) is performed for the circular tubular XKKJoints to demonstrate the strength capacity, plastic development zone and destruction forms, as well as stress and strain distribution status of the connections. After being analyzed several groups of XKK joints with different geometric characteristic, the influence of geometric parameters on the ultimate strength is investigated and explained graphically. Furthermore, the design strength capacity of the joints is calculated based on national code compared to the results from FEA analysis. The results indicate that with the increase of β1(diameter ratio of branch to chord) and β2(diameter ratio of another branch to chord), the bearing capacity of XKK joints will be improved. The angles of branchchord and branchbranch have little influence on bearing capacity. And the γi (ratio of diameter to thickness) should be controlled in a certain range. Based on the bearing capacity formula of X and K joint and some reference data，the strength formula for circular tubular XKK joint is suggested.

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Interface Behavior of RC Beams Strengthened with Carbon Fiber Laminates After Releasing Prestress

XIE Jianhe, GUO Yongchang, HUANG Peiyan

. 2011, (5): 123-128.

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This study investigates the interface behavior of reinforced concrete (RC) beams with strengthened carbon fiber laminates (CFL) prestressed by precompressing beam. With the soft behavior of the interface, an analytical solution for the interface stress of strengthened beams with prestressed CFL after releasing precompression is presented. By regarding the fracture energy as a criterion of the interfacial debonding, a theoretical model to predict the critical prestress level of initiating debonding is proposed. Moreover, some experiments were carried out to verify the analytical solution of CFL longitudinal stress. The results show that the analytical solution of the CFL longitudinal stress is basically in agreement with that of experimental values. It is also found that an abrupt increase of the interface shear stress arises in the CFL end after releasing prestress, and the increasing of the thickness or elastic modulus of CFL is benefit for avoiding debonding on releasing prestress.

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Study on Mechanical Properties of Layered Hybrid Fiber Reinforced Concrete

LI Lin，ZHANG Yafang

. 2011, (5): 129-133.

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Mesolevel numerical models of plair concrete ,layered steel, integral steel fiber and layered hybrid fiber reinforced concrete(LHFRC) have been generated in this paper. By anacysing and comparing their results,it is demonstrated that the layered hybrid fiber reinforced concrete can significantly improve the bending strength and toughness of concrete.

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Investigation on the Influence of the Airentrained Content on the Mechanical Properties of Concrete

XIAO Jianqiang，XIA Xiaozhou，ZHANG Qing

. 2011, (5): 134-136.

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The decreasing influence of the air content on the Young’s modulus of the concrete is studied by HS estimation method. Basing on the assumption of the DP yield criterion of concrete matrix, the macroscopic stress states on the yield surface can be theoretically obtained from the solution to a sequence of viscoplastic problems defined on the representative volume element. Introducing the energy density supporting function and constructing the approximating function sequence solve the non derivable problem on the boundary of the air hole. Finally, the macroscopic DP yield criterion of airentrained concrete is derived and the influence of the air content on the macroscopic friction coefficient and the dilatant coefficient of concrete is studied.

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Risk Analysis of Vshaped Pier in Construction Process by Means of RBF Artificial Neural Network

WANG Lifeng, XIAO Ziwang, WANG Ziqiang

. 2011, (5): 137-141.

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By taking finite element analysis results as sample data, an invisible mapping relationship between basic variables and structural response is established and a risk quantitative analysis method of highrisk location identification during Vshaped pier construction, by using RBF (Radial Basis Function) artificial neuron network is presented. Through a numerical simulation based on the principle of Monte Carlo, structural failure probability of each checking section of Vshaped pier during construction is calculated. It is proved by engineering project and concluded that, the method of construction risk analyzing based on radial basis function neural network can be used as an efficient reliability analysis method. It is reasonable and applicable, which can provide a theoretical basis for riskdecision during Vshaped pier construction.

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Higherorder Polynomial Optimization of Small Flow RateAeroengine Airinlet Simulated Test

HUANG Zhennan, ZHAO Yong, XIONG Jingqi, HUANG Hongzhong,
HUANG Li, ZHANG Zhong

. 2011, (5): 142-146.

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This research tackles with the small flow rate aeroengine airinlet system using the feedback control of airintake flow rate. Firstly, carry out the high altitude platform semiphysic simulated test on airinlet system. Secondly, establish the airinlet gate upward regulation, downward regulation and PID compensation models, then optimize the model parameters by higher order polynomial using simulated test data. Finally, all control models are combined under different work states to carry out the full process simulation. Its dynamic error is fluctuating within 0.471%, while its stable error is fluctuating within 0.096%.

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Experimental Research of Electronic Differential Control forInwheel Motor Drive Electric Vehicle

YU Houyu， HUANG Miaohua，ZHANG Zhenguo

. 2011, (5): 147-151.

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The inwheel motor drive electric vehicle is a novel electric vehicle and the electronic differential control is one of its key technologies. For the low speed fourwheel independent drive electric vehicle, the differential relationship among four wheels is analyzed according to the Ackerman steer model, and then is determined through the push and steer test at different steering wheel angles. The electronic differential among four wheels is achieved through four parallel PID control closed loops of inwheel motor speed. The proposed electronic differential control based on the differential relationship among four wheels determined through the push and steer test for the inwheel motor drive electric vehicle is validated through the actual road test.

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Chaos Control in Oscillating Circuit with Random Parameter

MA Shaojuan, ZHAO Tingting

. 2011, (5): 152-155.

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Based on the Chebyshev polynomial approximation, the chaos control of the oscillating circuit with random parameter subjected to vaulted distribution is considered. Firstly, the oscillating circuit with random parameter, according to the theory of orthogonal polynomial, is transformed into the equivalent deterministic one, which is weighting mean approximation under tiny mean square residual error in comparison with the original system. Secondly, the nonlinear differential feedback controllers are designed to control the system into the unstable periodic orbit by adjusting the control intensity according to the parameter bifurcation picture. Finally, the numerical results show the effectiveness of this method.

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Performance Analysis of Differential Frequency Hopping System with Linear Combining Receive Diversity

QU Xiaoxu， WANG Shu,LOU Jingyi

. 2011, (5): 156-160.

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A differential frequency hopping (DFH) system utilizing receive diversity based on multiple receive antenna is proposed to improve the antinoise performance of DFH system. Squarelaw detection linear combination rule is used in signal combination. Performance of this system under Rayleigh fading channel is analyzed with momentgenerating function method. Symbol error rate (SER) in closed form is derived with the general case when fading parameters and background noise levels of signals of different branches are all nonidentical considered. Numerical and simulation results show that space diversity using multiple receive antennas can improve the antinoise performance of DFH system remarkably. The performance improvement is approximately 7 dB better than system without diversity at SER of 10-4 when double receive antenna applied. Performance improvement increases with the number of receive antennas but the further improvement extent decreases. Branches with much lower signaltonoise ratio than other branches should be removed from combining otherwise system performance may be decreased comparing with systems without these branches.

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Simulated Annealing and Genetic Algorithms Based on Image Segment with Partially Evolved Hopfield Neural Network

HE Hanqing，NI Xianggang，LI Zhijun

. 2011, (5): 161-164.

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A combined optimization of genetic algorithms with simulated annealing
has been applied to image segmentation with good results in this paper. The def
ect of Hopfield neural network is being captured by local optimal solutions, whi
le the defect of genetic algorithms is the low speed of convergence. Both disadv
antages mentioned above have been overcome here. Solutions obtained with the con
verged Hopfield neural network are applied to the genetic algorithm to search fo
r the optimization on the plane of threshold value.

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