2012 volumne 33 Issue 02
WANG Zhongyong,LI Xiang,WANG Xingye,etc;
Abstract: In this paper, a novel separation method for nonlinear non-Gaussian signal is proposed. Accordingto the state space model, the issue of separation was changed into the joint estimation of the parameter andstate of the signal. In order to solve the problem of multi-signal separation for nonlinear systems, the algorithmuses particle filter method, combined the kernel smoothing contraction technique. The simulation results showthat, in nonlinear system, compared with DEKF algorithm, the proposed method can solve the problem ofmulti-signal separation effectively.
SUN Gangcan,DANG Manman,XU Xuefei
Abstract: This paper proposes a new algorithm for blind estimation of parameters of OFDM signals under mul.tipath channel based on the autocorrelation properties and the cyclostationarity of OFDM signals. The autocor.relation of the OFDM signal is firstly applied to estimate the useful data period, then we introduce average ideawhen estimate symbol period based on the second-order cyclostationarity character of OFDM signals in mul.tipath channel, and get more accurate OFDM symbol period by getting the average value of the cyclic frequencies, so the proposed algorithm has better performance. The simulation results show that the blind parametersestimation accuracy rate of this algorithm can reach more than 90% with SNR equals to -2 dB, as well as al-most 100% when SNR equals to 2 dB.
WU Fengxiang,YUE Xiao,XU Jiangfeng
Abstract: A new semi-fragile watermarking authentication algorithm is proposed, the algorithm first dividethe image into four blocks, then the feature of each block of image is extracted from low frequency coefficienof three level wavelet transform, and then the feature as the watermark is embedded into corresponding blockof image, the four blocks embedded into watermark were combined into a new image. The watermark can beextracted without involving either the host image or the original watermark. Theoretical analysis and experi.mental results show that the algorithm can be carriers of images of any size, and with good transparency, andit can not only resist non-malicious attacks, such as noise and lossy compression, it can also efectively detectand locate the cut,replaced, and other malicious attacks.
ZHANG Duanjin,MENG Shan,GUO Hao,etc;
Abstract: This paper studies the design problem of robust fault detection filters for Delta operator discrete sys.tems with state delays. Based on the traditional filter using the shift operator, a new filter model to fault detec.tion for Delta operator systems with time-delay is given. Sufficient conditions for the existence of the robustfault detection filter and its explicit expressions are developed in terms of linear matrix inequalities ( LMls) approach. When [.Mls are feasible, the optimal robust fault detection filters of Delta operator formulated systemsare obtained. The presented results can bring the fault detection for continuous time systems and discrete timesystems into the unified Delta operator framework, The simulations show the effectiveness of the proposed approach.
GAO Xiankun,CUI Yan,YU Yongchang
Abstract: For the co-channel interference in multi-user MIMO system, an improved SLNR ( signal-to-leakageand-noise-ratio) pre-coding scheme is proposed, to solve the problem that the system performance declineswith the increase of interference user. Combining BER performance and channel quality, the proposed schemetakes firstly the known multi-user co-channel interference int SLNR maximization criterion to be suppressed.uses SNR ( signal-to-noise-ratio) sort each user’s pre-coding matrix, then utilizes the known muli-user co-channel interference to iterate and optimize the follow-up user’s pre-coding matrix, which can further improvesystem performance, Without collaboration between base station and user, the proposed scheme merely utilizesthe channel information at transmitter to optimize pre-coding matrix, has low complexity and faster conver-gence. Simulation result shows that both BER performance and system capacity gain are greatly improved compared with the original SLNR, especially in high SNR.
LIU Guangrui,LIU Jun, KONG Lingyun
Abstract: Abstract: Path planning of mobile robot is a hunting for optimal or suboptimalcollisionless path from startingpoint to destination point according to one type of performance index, The ant colony algorithm is applied tothe path planning of mobile robot, the principle of ant colony algorithm of path planning for mobile robot is represented in the first place, then it is pointed out that the interaction course of ant colony algorithm is theMarkov process, the convergence of ant colony algorithm is analyzed, and the improvement method of conver.gence for ant colony algorithm is put forward. The simulation results show that: the algorithm in a short periodof time to plan a better path ,and effectiveness and feasibility of the algorithm is certified by simulation analysis.
WANG Jie,LIU Qi,DANG Qinhua
Abstract: The research of membership function and its determination method is of great signifcance. For de.termining the membership function expressed by Gaussian or sigmoid function ,this paper develops a density in.dex based on single-shot clustering method. The calculation amount depends on the number of input data line.arly and the center and the membership degree of engineering data can be easily obtained. Through simula.tion, membership funetion of the data EB_DaSl from the petroleum drilling in Ebei is established, and theproblem that membership function is hard to be described has been solved in paper.
CHEN Weihang,TAN Meiting,ZHANG Jie
Abstract: On the basis of single-factor test, the response surface methodology( RSM) with 4 factors and 3 lev.els was adopted to optimize ethanol extraction technology of procyanidins from Lotus Seed Pot( LSPC). The in.teractive effects of the parameters on ISPC yield were investigated. Design Expert 7. 1.6 software was used tofit experimental data and a quadratie polynomial regression model was developed for LSPC yield as a responseto the parameters, Results showed that the optimal value of extraction conditions were as follows: ethanol con.centration 50% , solvent/material ratio 25 m[/g, extraction temperature 55℃C and extraction time 60 min. Un-der such conditions and extraction 1 time, the yield of LSPC was up to 6.678 mg/100 g, which is close to thepredictive yield(6. 693 mg/100 g). This model is reasonable and reliable, and can be used in the actual fore-Cast.
HUANG Qiang,MENG Qingyi,NIU Bolin,etc;
Abstract: Two mixed strains of microorganism capable of optically resolving, racemic glycidyl butyrate havebeen isolated from soil and identified to be alkaline lipase , which one strain of lipase has no ideal result fromtens of lipase. The suitable carbon source of the condition was starch and the nitrogen source was beaf extract.The proper temperature and initial pH for enzme formation were 30 ℃ and pH = 8.0 respectively. Rotatingrate was 200 r/min. Under two days fermentation, it can reach 1.5 u/mL. The technology of the two alkalinelipase in the optical resolution of glycidyl butyrate was studied. The condition was pH 6. 0 , 28 ℃ ,200 r/min,0. 50 g substrate added in the alkaline lipase liquid, when the glycidyl butyrate was transformed by 83. 2%,the optical purity of (R)-glycidyl butyrate was 92.8% ee( enantiomeric excess).
GUO Xiali,YANG Xiaoli,WANG Yan
Abstract: By measuring pH,cellulase activity ,microbialcompositionano theefficiency of corn-stalkdegra-dation, the properties of a composite microbial system in decomposing corn stalk were investigated using batchexperiments. The results indicated that the system pH remained stable at between 6. 5 to 7.5 during the cornstalk degradation. C,enzyme ( β-glucosidase), C,enzyme (endo-β-1 , 4-glucanase) and C, enzyme ( exo-β.1 , 4-glucanase) were, in tumn, into highly active stage with the degradation of corn straw. There was a goodsynergic effeet between them, The number of fungi maintained at a high level. The straw degradation efficiencyhad been a steady increase along with the bacteria amount increasing all the time in the whole process of cornstraw degradation, The results showed that the straw-degradation inocula was stable.
ZHANG Yadong,PAN Kailin,LIANG Zhengyong
Abstract: Kineties for synthesizing n-octadecanethiol from 1-chlorooctadecane and thiourea was studied. Thereaction kinetic model of first process was investigated in the condition of homogeneous reaction, It was a firstorder reaction and the kinetics equation was written as ra= -dc /dt =4.602 x 10exp( -13 464. 27/T)CA,the activation energy was determined to be 111.95 kj/mol in the Arhenius equation, the reaction of synthesi.zing n-octadecanethiol belonged to control production of chemical reaction because the apparent activation en-ergy was in the range of 40 ~ 400 kj/mol, Finally, the kinetic model was tested and verified by experimentsThe example systems demonstrated the validity and rationality of the method.
WANG Xunqiu,WANG Hui,YAN Bingli,etc;
Abstract: In order to calculate the vapor-iquid equilibrium ( VLE ) data of the multicomponent system, theVLE data of cyclohexane-cyclohexanone system were determined under normal atmospheric pressure ( 101. 3kPa) by using an improved Rose vapor-liquid equilibrium still, and the thermodynamic consistencies of theobtained data were examined. ’The results show that the experimental data satisfy the examination of the ther.modynamic consistencies. Then the VlE data obtained were correlated with Wilson equation and NRTL equa.tion respectively, and the model parameters of interaction energies between the molecules were determined byusing the error sum squares of vapor phase composition as target function. The comparison of the experimentalVLE data with those calculated with Wilson equation and NRTL equation shows that the deviations are little,which indicates that the models are suitable to be used for the engineering separation design.
ZHOU Junjie,FANG Quanguo,WANG Dingbiao
Abstract: Through simulation software Matlab/Simulink ,this paper gets the Pll controller parameters of fuelflow ,steam pressure and air flow control system by using the method of Ziegler-Nichols,establishes the simula.tion model of combustion process control system. Simulation results show that if the fuel flow and air flow aredisturbed by chip signal, steam pressure maximum overshoot is 0, 36% , and the response time is 46. 5 s,stability and response speed of control system are quite good, MA’TLAB/Simulink software provides an effectiveway for the analysis and evaluation study of combustion process control system
LU Hongxia,YU Xiujun,HAN Yanli,etc;
Abstract: Zno nanorods with 100 ~200nm in diameter and 2.0 ~3.0um in length along [0001 ]orientationwere prepared with simple one-step hydrothermal method using ZnSO, · 7H,0 and NaOH as reactants. Efectsof OH" concentration , reaction time on the morphology and photoeatalytic properties of products were investi-.gated by X-ray diffraction, scanning electron microscopy and UV-vis absorption spectra. The results show thatZn0 nanorods have good photocatalytie properties to methylene blue trihydrate and the controllable synthesiscan be achieved by altering OH" concentration and reaction time. OH" concentration and reaction time havegreat influence on the morphology and photocatalytic properties of products.
CUI Tiebing,ZHANG Chen,XU Li
Abstract: Using V,O, as main active component, silica gel as carrier, the cocatalyst selection was carried outby taking the conversion of the naphthalene and the selectivity of 1 ,4-naphthoquinone as criterion, it was deter.mined that $n$0, , sodium borate was main cocatalyst. Furthermore , the proper quantity of stannous sulfate added in catalyst was determined to be 1.8 96 by mass fraction at the ratio of potass to vanadium of 3. 17 in mole.Reaction based on this catalyst caused 1 ,4-naphthoquinon yield of more than 90% , and its selectivity of almost10096 . Basification of catalyst made the selectivity of 1 ,4-naphthoquinone increase by 15% on average.
MENG Cairu,FENG Zhongxu,LI Lei,etc;
Abstract: The sereening efficiency did not meet the national standards, which made the concrete gradation notexact, It is one of the causes for early damage roads, so the urgent problem to be solved is to improve thescreening efficiency of the vibration sereen. The 5$ZD260 vibration screen was tested about the screening eff.ciency in the asphalt mixing plant. The vibration parameter and the stress parameters on the vibration screenwere tested. The low screening efficiency was mainly due to low amplitude, but improving the amplitude of thescreen directly influenced the intensity of the screen and its service life. In order to make a detailed analysis ofthe vibration screen about its intensity, the vibration screen was simulated in ANSYS about the static stress,thermal stress and model. And then these were tested for inspecting the results. When the amplitude of the vi.bration screen increased to 4mm and the vibration force enhanced on the original 1.6 times, the sereening eff.ciency can reach the national slandard and the intensity of the screen box was also enough.
GAO Liang,LIU Jianxin,GUO Wei
Abstract: Through the section model wind tunnel test, this Paper studies the influence of vibration dampingmeasure to the three-component force coefficient of the structure , in order to improve structural characteristics.The research based on the guide plate position, the central trough opening rate, baluster drafty rate, repair cartrack position , windbreak , vehicle as the influencing factors of three-component force coeficient. The resulteshow that the changes of the three-component force coeficients directly affect the static wind loads, and the in.fluence of changes of these parameters to the static wind load can not be ignored. The most obvious influencepavement to drag coeficient is windbreak, in the large attack angle, the resistanee coefficient rose of comple-ted status with windbreak.
ZHAO Guijuan
Abstract: In order to study the influence of different foam asphalt content and content of milling material fromasphalt pavement ( RAP ) on splitting strength of the foam asphalt recycled mix, two different milling materialfrom asphalt pavement which will be called RAP, and RAP, were chosen. The old material volume which is respectively 0%,20%,40%,60%,80% and the foam asphalt content which is 2%,2.5%,3% ,3.5% ,4%were mixed, and mixed foamed asphalt recycled mix , molded piece, determined dry and wet splitting strength( ITS) and residual spliting strength ratio ( TSR ). The results showed when old material content proportionwas a certain condition, the foam asphalt content of mixture reached an optimum value. As the RAP contentincreased gradually, optimum asphalt content of foamed asphalt recycled mix was reduced gradually, and thevalue changed from 3.5% when RAP was0 to 2% when RAP was 80%. As the RAP content increased, drand wet ITS of foamed asphalt recycled mix decreased, but TSR increased.
WANG Guoyan,ZHAO Pengtuan
Abstract: A telecommunication tower is liable to be overturned under strong wind since the tower body is ahigh-rise structure. Based on inertial wind load method, in consideration of the distribution of multiple spatial6 models and the segment shape coeficients of tower body according numerical wind tunnel, wind-induced re.sponse of tower body in 13 different wind attack angles are calculated, Based on the wind-induced responseand the wind loads on motor room, analysis of anti-overturning of tower is checked. The research results arethe most unfavorable attack angle is 90°direction and the scientific data for the design of mobile foundation is15.8t. The results of analysis show that the method adopted in this paper is reasonable, at the same time themethod is presented for the analysis of wind-induced and anti-overturning of structures such as the telecommu.nication tower.
CHEN Cheng,YANG Ping,ZHANG Ting
Abstract: Liquefied nitrogen freezing replacement shield brushes tail in China is the first application in shieldtunnel excavation. With Qingchun Road cross-river tunnel of Hangzhou as an example, this paper appliesADINA finite element calculation software to compute thermal field for artificial thawing 3-D model, studiesthermal spatial distribution and the variation laws of temperature with time, and makes the sensitivity analysisfor influence factors of thawing temperature field. Through the contrast analysis of numerical simulation andfield measurement, we get the development regularity of artificial thawing temperature field; artificial thawingtime is longer with the increase of thermal conductivity and the increase of heat capacity; the higher the circu.lation hot water temperature is, the shorter the time of thawing is shorter; artificial thawing time is longer withthe increase of latent; which solves the problem of shield brushes tail replacement in high-confined aquifer.
ZHANG Jinping,LIU Junge,GUO Bingtuo,etc;
Abstract: Water is essential to the process of daily consumption, and the change of consumption patterns isdirectly related to water consumption. Virtual water consumption of city and country residents in Zhengzhouwas calculated and analyzed from 1999 to 2008. Results show that, virtual water consumption of Zhengzhouurban residents has a growing trend year by year, whereas the water consumption of Zhengzhou rural residentsdeclines slightly. The virtual water consumption of city per capita is 1.6 times as great as country per capitaconsumption, moreover, the diversity index and evenness index of urban residents is higher than rural resi.dents, Thus, in order to narrow the gap between city and country areas, it is necessary to increase the incomeof rural residents and improve the consumption level; and at the same time people’s consumption habitsshould be correctly guided to improve wgter use efficiency.
SUN Kang,CHEN Wen.
Abstract: The dynamics analysis software ANSYS/LS-DYNA is applied to establish the FSl( fuid and solidinteraction ) model of unloading cartridge valve in a huge metal extruding machine in this paper. Through sludying algorithm and control state equation of the fluid-solid coupling unit and the simulation analysis of fuidsolid coupling, this paper studied the transient mechanical characteristics of cartridge valve and the impactcharacteristics under the interaction of the valve core in unloading process. The results show that: the stabilityof unloading process is related to the contacting time between valve core and valve set, the oil squeezing timehad better not exceed 0.01 second, the peak impact force of oil to valve core is 140 KN in a steady unloadingprocess, and the maximum Von Mises stress between valve core and valve set is 456 Mpa.
ZHAO Jingying,CHANG Liang
Abstract: With existing equipment of AS/RS as the main basis, this paper puts forward oplimization measuresthat can improve automation level of AS/RS , to meet the needs of normal production and achieve the core ob.jective to reduce 10% storage space. Operation results of Flexsim simulation model show the comparison be-tween optimization scheme and current scheme : the maximum utilization rate of single package depot increasesby 12. 3696 , the average utilization rate of multi-body package depot increases by 5. 32%6 , the average utiliza-tion rate of entire board depot increases by l.279% , and the safety stock needs of factory is not affected.
ZHANG Aili,ZHU Tianlong,CAI Wuzhen
Abstract: The dynamics analysis software ANSYS/LS-DYNA is applied to establish the FSl( fuid and solidinteraction ) model of unloading cartridge valve in a huge metal extruding machine in this paper, Through stud-ying algorithm and control state equation of the fuid-solid coupling unit and the simulation analysis of fuid.solid coupling, this paper studied the transient mechanical characteristics of cartridge valve and the impactcharacteristics under the interaction of the valve core in unloading process. The results show that: the stabilityof unloading process is related to the contacting time between valve core and valve set, the oil squeezing timehad better not exceed 0. 01 second, the peak impact force of oil to valve core is 140 KN in a steady unloadingprocess, and the maximum Von Mises stress between valve core and valve set is 456 Mpa.
CHEN Jiangyi,JIAO Liming
Abstract: In this paper, the parameters of machine tool spindle are determined based on the theory of themultidisciplinary design optimization ( MDO). To minimize the weight, the deflection and the shear stress ofspindle synchronously, a two-level optimal model including one system model and three sub-models is con.structed with the collaborative optimization algorithm. Then a commercial software iSIGH’T is employed to solvethe two-level model. it ensures the minimal weight of spindle, while it has better stiffness and strength. Itproved to be better than those provided by the existing literature, This fact also shows that MDO is a valuabletool for multi-objective optimal problem of machinery design.
HU Shicheng,LU Xiaohong,WANG Xiangjun,etc;
Abstract: Compared with the method that power of the hydraulic pump is lower than that of the engine, a newmethod is put forward from the special view point of energy saving in power system of horizontal directiona!driling, and the power of the hydraulic pump is proposed to be higher than that of the engine, according to theanalysis of the power match of horizontal directional drilling. The main controller controls the displaced volumefrom the variable displacement pump when the load pressure changes and the variable displacement pump canabsorb the outputs of the engine entirely. The engine can run stability at the expected speed. Establish theAMESim modal of horizontal directional drilling, the scheme of proportion-integral-differential( PlD ) is appliedto the energy saving system, the emulation and the experimental results show that engine speed fluctuation iscontrolled within 50 r.min-1,which reduces the power loss effectively.
YANG Jiewei, ZHA0 Jiangming
Abstract: In this paper, the characteristics of driving technology used in microrobot are introduced. Somekinds of driving technology based on different principles are summarized and the research advancement is pres.ented. Furthermore, some technology problems and prospects in the future are analyzed, The appropriate pro.pulsion methods in different fields are discussed. One way of microrobot’s development is wireless, With thedevelopment of smart material, micromachining and magnetic field driving technology, microrobots have greatpotential for medical applications in the human body
FAN Aiwan,CHANG Qiang,LU Shuxi,etc;
Abstract: The ECC sequential multiple digital signature scheme is designed based on eleetrical dispatchingsystem, in view of the limitation of low execution speed and great size of memory of RSA in electrical dispatc.hing system. The scheme will process the identity of signer and the dispatching documents by hash function,avoid the attack of alternative identity and ensure the integrity of information; the digital signature process a.voids the inverse operation, and lowers the complication of time; the signing result of each dispatching signerwill be sent to the signature center, avoid joint cheating and ensure the verifiability of valid ticket, and the se-curity of electrical dispatching system is then solved, The application test indicates that the duration of signa.ture and verification of the scheme is short, with relatively small communication and the requirement of real.time for power dispatching is satisfied.
ZHANG Bo,YANG Xinzeng,ZHOU Yong
Abstract: This paper introduces the ampere-second characteristics of fuses and takes the case of an 110kvsubstation in Henan province to analvze the main reasons of its multi-fuse failure: one is improper parametersincluding small rated current of fuses , low rated voltage of capacitors and big capacity of individual capacitors ;the other is the problem of the relaying protection configuration that the overvoltage protection of capacitorsdoes not function properly, With parameters of fuses and capacitors adjusted and zero sequence overvoltageprotection devices for capacitors installed, improved compensation device has not had any multi-fuse failure inoperation so far.
SUN Zhenqi,HUANG Minghui,LIU Changfa
Abstract: Ti-6Al-4V is an important alloy in aviation field. In this paper, orthogonal experiment method wasused to optimize the parameters of surface treatment, which affect the results of the anodization. The best pa*rameters were obtained with this method: 250 g/L of solution concentration, 10 V electric voltage and 15 mi.nutes anodization time, 25 9 experimental temperature. Brown, tight and porous oxide layer was developedon the surface of titanium alloy. This oxide layer increased the surface of the sampld, and enlarged the in.termeshing strength between the cohesive and sample during bonding. Mechanical test results showed that thecohesive joint shear strength comes up to 34.54 MPa according to this optimized program.
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