2014 volumne 35 Issue 05
SHI Li,CHEN Jian-wei, WANG Song-wei
Abstract: Electrodes were expensive consumables of electrophysiological experiments. Cheap and homemademicrowire electrodes had been widely applied, but their implantation performanee was not good. To fabricatelow cost and aeceptable performanee of microwire electrode, first, the key factors affecting the longtemm re-cording performance was analyzed and the direction of the enhaneement of eleetrode was determined. The ex-isting fabrication process was improved through electrode fabrication and the eleetrode tip surface modification,and the impedanee model modified electrode was established and its properties, signal acquisition ability andbiocompatibility was systematically evaluated. The result showed that the improved electrode tip surface wassmooth and tidy, and its model was effective and its impedance decreased by 56.196 on average; record signal-to-noise ratio was higher; recording longevity reached 45 days ; biocompatibility was better. It met the re-quirement of the general eleetrophysiological experiment.
LI Jianyong,ZHAO Feng,DING Qingqing
Abstract: The exeilation conlrol of power systems under generator tripping emergeney measurement is invesli-gated. First, a switched dynamie model for a typieal lEEE three-machine multi-area power system is devel.oped. Then , the switched power system is transformed to an equivalent switched dissipative Hamiltonian sys.tem via pre-feedback control. A state feedbaek switching eontroller is constructed based on the dissipativeHamiltonian realization. Using the Hamiltonian funetions of the subsysems as multiple Lyapunov funetions, itis shown that the closed-loop system is asymptotically stable under arbitrary switching path. Simulation resultsdemonstrate that the proposed eontroller ean elfeclively improve the transient stability of the power system.
Ll Haoliang,SHUI Qinghe,FAN Wenbing,
Abstract: Since outdoor sports vehicle shadows exist in the proeess of vehicle detection, this paper proposes anovel method of vehicle shadow elimination. With the adaptive Gaussian mixture model ( AGMM) for back-ground modeling, we can get the background and the frame of the video sequenee, we can use the improvedLaplaee of Gaussian funetion ( L0G) edge deteetion operator to conduct two times edge deteelion to the fore.ground image and the foreground of threshold segmentation. Finally , for keeping the vehiele movement area, weshould have the foreground edges of the two times deteeting results subtracted. This experimental result showsthat the novel algorithm ean elfeetively remove the light shadow which is close to the vehicle characteristies.
MAO Xiaobo,ZHANG Zhichao
Abstract: Aiming at the problem that most learning-based super-resolution algorithms are not eompetent totake both the reconstruction quality and eomputing speed into aecount, a novel single image super-resolutionreeonstruetion based on Bidimensional Empirical Mode Decomposition ( BEMD) is proposed. Firstly, a low.resolution image is decomposed into several layers with different complexities by BEMD, which contains vari-ous details. Then, the first lMF be reconstrueted with high frequeney details by improved kernel ridge regres.sion algorithm in order to ensure the quality of image and the other lMFs eontaining fewer details be reeonstruelby bicubie interpolation in order to improve the speed. Finally, the reeonstructed IMF’s are merged into a high.resolution image. Experimental results demonstrate that the proposed method make full use of the advantages olthe above algorithms, which not only ensure the quality of the reeonstruction image, but also improves theeomputational speed.
LI Jiyun,NIU Zhiling,PEI Hong-xing
Abstract: A design method of serial communieation protoeol was developed between PC and lower computer torealize graphies processing control in self-developed laser miero processing system. Through the image proeess.ing, irregular pieture was changed into binary image formed by m rows and n columns. Each row consists ofmany segments with alterate need and need nol machined. All the rows were selting value. A frame, trans.ferred to lower controller using serial communieation, was composed of start text (STX ), bytes, funetioneode, data, cheek-sum and end text ( ETX ). Before exeeution, each reeeived frame would be checked. Theresult of review and execution need feedback to PC. The feedback frame was the evidenee determined if theframe needs to be resent. The data frame feedback method ean improve the reliability of eommunieation.
ZHOU Yong,ZHU Mingli,DU Xia,etc;
Abstract: In order to realize the online remote monitoring of power quality, the 32-bi TMS320F283335 floal.ing-point digital signal proeessor is applied to collect on-site voltage and current data, which is uploaded to thehost computer through the wireless transmission unit, and the real-time power quality monitoring and analysisis realized in LabVlEW environment. Test results show that the system have advantages such as stabilitly of operation and geographieal adaptability, and can thus well meet the requirements of power quality monitoring andtransient event recording.
WANG Dongshu,ZHU Xunlin
Abstract: Suitable path planning is precondition of autonomous robot exploration in unknown complex environ.ments. Traditional path planning methods focus partieularly on planning an un-eolliding path from the start po.sition to the goal and robot attitude stability is selom considered. A new path planning approach consideringrobot’s attitude stability and energy consumed in outdoor complex environment is proposed, which consists olthree steps; (1) gradient caleulation , gradients of the rough terrain are ealeulated: (2) node deteetion, terrain is divided into llat regions and rough regions aeeording to height threshold; central position of each lat re-gion is reeognized as the node; (3) path evaluation, the oplimal path from current position to destinationthrough intermediate nodes is planned based on the cost evaluation funelion. Compared with the conventionalapproach, the effectiveness of the proposed method is demonstrated through simulations.
LUO Shuzhen,GENG Hengshan,XU Xiangnan,etc;
Abstract: This paper systematically introduces the working prineiple and structure of streaming media livingsystem based on H’TTp live streaming protoeol( also known as HIS). lt makes a deep research on interacttransmission proeess belween client and server with the network data analyzer and analyzes detailedly the re.dundaney problem of video index files being repeatedly downloaded when applying this technology in networktelevision broadeast. But the current technology brings about the waste of nelwork trallie and the reduclion otransmission eflicieney. In view of these problems, we put forward an improved mark-method technique whichadd a new tag in m3u8 file. A ealeulation was carried out to testily the method and it proved it ean elfeetivelyreduee the waste of net flow rate , improve the transmission performanee and have great feasibility.
LI Anxin,ZHANG Jiangfei,ZHANG Zulong
Abstract: With the magnetie resonant coupling wireless power transfer system as the research objeet in thispaper, the magnelie resonanee system dynamie model is made by using coupling mode theory, from the energyfield eoupling and deeay charaeteristie angle explains the cireuit meaning of the key parameters, and then thesystem oulput power and transmission efficieney expression are derived in this paper. Through contrast analysisof the output power and transmission ellieieney expression which is derived by equivalent cireuit method, it iseoneluded that the two kinds of modeling method with consisteney eonclusion as to the same coupling system.Finally, the quantitative relationships between the output power and eoupling eoelficient and between thetransfer ellicieney and coupling eoelfieient are given, which verily the correetness of the theorelieal analysis re.sults, and the eonsisteney of two kinds of modeling method in the output power and transmission efficieney isverifed indirectly.
XU Zhihong,ZHANG Yuemei,WANG Yi
Abstract: The topie search’s eore is the contents of the mateh which is based on the Chinese word segmenta.tion , but the Chinese word segmentation’s aeeuraey and unregistered word’s reeognition is still the bouleneckof the topie seareh. This paper proposed an improved maximum matching of word segmentation algorithmIMMM. In improved algorithm designed thesaurus pretreatment, unknown word proeessing and disambiguationstrategy, combined subjeet categories and sub-word dietionary storage , finally construet a topie search systemThe algorithm results show that the improved algorithm is better than traditional algorihms, and the search ae.curaey rate has been greatly improved, The system’s efficieney is improved.
CAI Lina,CHEN Shuwei,ZHOU Wei
Abstract: In order to aggregate the information expressed in the form of interval-valued hesitant fuzzy sets, wepropose in this paper an interval-valued hesitant fuzzy WOWA ( Weighted Ordered Weighted Average) opera.tor. The novelty of this operator is that it not only considers the importance of data, but also considers the importanee of loeation where the data is sorted. Then, some properties of interval-valued hesitant fuzzy WOWAoperator are diseussed, and one deeision making method based on the interval-valued hesitant fuzzy WOWAoperator is presented. Finally, an illustrative example is provided to verily the rationality and effeetiveness olthe proposed operator and decision making method. The research in this paper has certain theoretieal valueand application prspect.
LIU Haitao,GUO Yuancheng
Abstract: There is an obvious yield stress for struclural solt soil, and extemal disturbanees result yield stressdecrease and compression inerease. Five-seelion line was used to simulate the compression curve of disturbedsoil, and virtual pre-consolidation pressure was put up aler the varied characteristies of pore ratio and stresswere analyzed in the proeess of deformation. Disturbed degree of solt soil that defined of logarithmie form waselosely connected with e-lgp curve, and thus conduetive to strength caleulation and deformation analysis of dis.turbed soil. Engineering praeliee showed that inadequate consolidation of soft soil should be considered whendisturbanee degree was ealeulated, and this method in the assay could reasonably prediet the ultimate setlle-ment of disturbed soil.
WANG Yanping,HUANG Youqin,WU Jiurong,etc;
Abstract: The light-weight portal frames are commonly used in single floor industrial buildings, and wind loadis one of the most important design loads. However, previous studies on structural wind effeet oplimizalion onlyconsidered the equivalent statie wind loads ( ESWLs) for a single-target, which might cause inaecurate resultsunder multiple constraints. In this paper, the ESWLs for multi-targets are constructed based on the database olwind tunnel tests, and the Optimum Criterion (OC) method is adopted to oplimize the wind elfeet of a portalframe with varying seetions. The height of web plates of the joist steel are selected as the design variables, theminimum weight of steel is the obieelive under the constraints of horizontal displaeement at the column top andthe vertical delleetion in the mid-span. The code is writen on the platform of MATLAB. Studies show thatconstrained displaeements under ESWLs for multi-targels are consistent with the peak random displacements.The oplimization makes the tolal weight deerease by 23. 296 , generating obvious economie benelits. Moreover.the oplimized sectional dimensions conform to the mechanieal characteristies of portal frames.
JIA Shanpo,LUO Jinze,WU Bo,etc;
Abstract: In view of the failure characteristies of layered roek mass, a series of physical experiments were car.ried out in this paper. The disruplion and strength fealures of the layered rock in the case of uniaxial eompres.sive are diseussed to explore the diseipline of the dip angle and interlayer changes elleet on strength and breakage of roek mass. The test results show that the roek mass destruetion modes are mainly rock destruetion fosmall dip angle (0 <45°), interlaminar shear failure with the dip angle inereases (45°≤θ<75°)and layerdireetly damage with loeal spliting failure for the dip angle of 90°. Abaqus soltware was used for the numeriealsimulation on the above model tests. The theoretieal analysis and numerieal simulation show that the compres.sive strength of rock is first deereased and then inereased with the “["-shaped disribution. The ealeulationresults are consistent with the resulls of laboralory test.
ZHAO Gengqi,LI Qing,QUAN Jiangwei
Abstract: With problems of shear wall with openings appearing in existing buildings, I analyze its impaet onthe overall strueture by PKPM after the openings of shear wall, and foues on bonding steel to reinforee shearwall with openings by the method of iso-strength exchangable. From the natural period, and displacement olthe strueture, and the ratio of rigidity-to-gravity, and the shear bearing capacity to verily the reinforeementelfeet. The results show that reinforeement ratio of the shear wall with openings redueed more, need reinforee.ment. The shear wall with openings bonded steel reinforeement has less effeet on the overall strueture in theaelual engineering, which is even able to reach the level before its opening. Using this kind of bonding steestrengthening method makes up for short of atlas of 06SG311-1. Therefore , this method can be applied to theactual projeet.
CHEN Weihong,MA Jingming,CUI Shuangshuang
Abstract: Organie epoxy adhesives are usually used in strengthening conerete structures with carbon fiber re-inforeed polymer (CFRP) sheets. However, due to the low soltening points of organie adhesives which are a.bout 60 9℃ , conerete structures strengthened with CFRP sheets bonded with organie epoxy adhesives can nomeet the heat resisting requirements. In this paper, an inorganie adhesive, which can resist at least 600 9high temperature, was prepared to paste CFRP sheets to strengthen four simply supported bonded prestressedeomposite beams eneased cireular steel tube truss after ulimate limit slate, and test on lexural behavior olthese four beams was also performed. Moreover, normal section load-bearing capacity of these beams and theeurve load-delleetion at mid-span were obtained. Experimental results show that it is feasible to strengtheneonerete members with CFRP sheets bonded with inorganie adhesive. Based on the experimental results andtheoretieal study, computational method of stiflness is proposed for caleulating bending rigidity and normal see.tion load-bearing capacity of conerete simply supported beams strengthened with CFRP sheets bonded with in.organie adhesive. The formula of ben
GAN Xinli,ZHANG Nan,LU Yu
Abstract: For the researeh of the technology performanee of PEG modified asphalt, the brookfield viseosity.penetration, softening point and duetility was determined, and the performanee of the PEG modified asphalwas analyzed. Through the determination of residual penetration ratio and residual ductility, the aging perform-anee of PEG modilfied asphalt was analyzed ; through the viseosity-shear rate curve, the rheologieal properly olasphalt was analyzed; the construetion temperalure of PEG modified asphalt mixture was obtained through theviseosity-temperature curve and it was analyzed. The results show that with the inerease of the blending rate olPEG, viseosity and sofiening point inereases and penelralion and ductility deerease; the ageing performanee olPEG modified asphalt is beter than the matrix asphalt; the PEG modified asphalt under 163’℃ presents thenon-newtonian feature ; the construetion temperature of PEG modified asphalt mixture obtained through the vis.cosity-temperature curve slightly higher than the common asphalt mixlure.
ZHANG Weidong,WANG Zhenbo,SUN Wenbin
Abstract: Based on axially compressive tests of conerete filled steel tubes short columns with waste conereteblock , the inlluenee of ineorporation rate of lower compressive slrength to maeroseopie charaeters of deforma.tion, load - vertical deformation curves and bearing capaeity-ineorporation rate were studied, and applicabilityof three theorelieal ealeulation formulas of conerete filled seel tubes were analyzed. The test results demon.strate that failure mode, duetility and later bearing eapacity of conerete filled steel tubes short columns withwaste conerete block is similar to conerete filled steel tubes, but the bearing eapacity will deerease when ineor.poralion rate of waste conerete block inereases, and the maximum amplitude is 14%. Based on the comparisonbelween the results of three caleulation theories and test results, different caeulation formulas are recommen-ded from different aspects.
LI Dalei,DAI Chaolei,NIU Penghui
Abstract: The new-lype vertieal milling machine was taken as the research objeet, and the 3D model of gear.box was ereated by SolidWorks and the model was simplified. By using the finite element analysis softwareANSYS Workbench ,we established the finite element model of gearbox . After the modal analysis and harmonicresponse analysis for the finite element model of gearbox, we could obtain nalural frequeney of preeeding sixorders , vibration mode and harmonie response curve. Aeeording to the nalural frequeney and main vibrationmode analysis , meanwhile the analysis of experiments verified the eorreetness of the simulation results and thecorresponding measures were put forward to avoid the resonance.
LI Yinxia,LIU Manman,GAO Junjie
Abstract: According to the in-depth analysis and study the eorrelated inlormation such as standards and normsof vehiele human-machine both in domestie and abroad, a five stratifieation tree evaluation indexes system ovehicle ergonomies which contains 105 indexes is built, then 15 expert drivers are referred twiee as the speeialized consultants upon preliminary index system with the modified Delphi method. Based on statistie treatment of consulting results, 86 indexes are chosen. The research and building of the indexes system providesbasis to the comprehensive evaluation of vehicle ergonomies, and provides some guidanee to the vehicle designand evaluation.
ZHAO Zhike,ZHANG Xiaoguang,WANG Xin
Abstract: A novel method of trend elimination for mechanieal vibration signal by loeal mean decomposition isproposed in this paper. LMD is a deereasing deeomposition proeess from high-frequeney component to low-fre.queney component step by step, and both in amplitude and frequenee of the residual component which is veryweak. In view of the low frequeney for the trend of mechanieal vibration signals, and the residual componenfrom LMD has litle impaet on the trend. Therefore, the last PF component could be the trend for mechanieavibration signals. In order to validate the correctness of proposed method in this paper, by using the method olnumerical simulation to build the common linear trends, polynomial and exponential trend for loading on thesimulation signal and the measured vibration signals of rolling bearings. The proposed LMD method, the con-ventional least square fitting method, the wavelet analysis and the EMD method can be used to extract thetrends respeclively. Numerical simulation test and the measured data processing results show that this methocean aeeurately extract the trend of the mechanieal vibration signal, compared with the other methods to extractthe trend, and LMD has a certain advantage.
ZHANG Xiang,WEI Haodong,YA0 Jilei
Abstract: Monodisperse size-controlled polystyrene mierospheres were prepared by dispersion polymerizationof styrene in ethanol dispersion medium, using PVP as a stabilizer and AlBN as the initiator. The inlueneefaclors, such as monomer coneentration , stabilizer coneeniralion , iniliator eoneentration and reaction temperature on the size and size distribution were invesligated. The morphology and size of PSt mierospheres was charaeterized by SEM , partiele size analyzer and oplieal mieroseope. And the Fourier transorm infrared ( FTlR )spectra of PSt mierospheres were also reeorded by a FTlR speelrometer. The results showed that monodispersePSt mierospheres in the size of 3.55 pm with smooth surlaee were prepared when the monomer coneentration is22%, slabilizer PVP is 0.65% , iniliator AlBN is 0.32% and reaelion temperalure is 70 ℃.
ZHAO Hongliang,DING Ziyang,LI Huaiwu,etc;
Abstract: The hypereuteclie Al-Si alloys were modified with Al-P master alloy and evaluation of machinabilitby comparing the tool life and surface quality at room temperature. The experimental results show that after AlP master alloy modilication, primary silieon becomes small, seattered and round passivation, the tool life is1.75 times than before , frietion-time curve becomes smooth and weight loss becomes small, and those resultsshow that materials hard particles for tool wear beeome smaller and modifieation improves machinability.
LU Guangxi,WANG Peng,GUAN Shaokang,etc;
Abstract: This paper studied the dross composition and dross Mechanism of nozze cavity on Hazelett continu-ous casted and rolled AA5052 aluminum alloy by seanning electron mieroseopy (SEM ),energy dispersive a.nalysis ( EDS ) ,X-ray diffraetion ( XRD), ete. Using The Gibbs free energy thermodynamie funetion ealeulat.ed driving forees of forming dross compound of nozzle cavity and analyzed formation on reaclion of dross compound of nozzle cavity. The results showed that dross eompound of nozzle eavity consisted of spinel, forsteriteFlorisil,ete. The Si0, or Al,0, in nozzle cavity reacted with Al, Mg and Mg0 in AA5052 aluminum alloy melto MgAl204,Mg2SiO4 , MgSiO3, which were mainly spinel composition during casting process, eventually lead.ing to drss of nozzle cavity.
GUO Xiali,WANG Xingsheng,ZHU Zhengwei,etc;
Abstract: In order to study the nitrogen translormation and composting period in high temperalure aerobiecomposting of vinasse, an experiment was carried out on the condiion of an open environment and natural ven-tilation, which is expeeted to provide seientilie basis and technieal guidanee for vinasse resouree utilization.results showed that: in the 28-day process of composting, temperalure reached 50 on the seventh day, thetemperature above 50 9 lasted 10 days; the content of NH4+-N ollered upgrade firstly and then deseendinglatter tendeney. Until the end of composting, the content of NH3- -N inereased by 82.0%. The content tend.eney of NO4+-N was eontrary to NH3--N and NO,-N content was redueed by 44.5%6 compared with theinitial stage. The content of Org-N and ’T’N had the same variation trend, olered upgrade firstly and then deseending later tendeney. Until the end of composing, the contents of Org-N and TN were 17.19% and 1.9%higher than initial stage respectively. On the 28th day, germination index reached 90.4%6 , compost maturityfully met the requirements. In consideration of the change of temperature and pH in the proeess of composting,it can be concluded that the period of vinasse compost is 22 days on the condition of open environment, naturalventilation and once artifieial turning every 3 days.
CHEN Weihang,LI Qingya,JlANG Yuanli,etc;
Abstract: Large amount of byproduets ( 1,4-Butylene glyeol and Diethylene glyeol) are generated in theprocess of eoal glyeol. The basie data were inadequate for separation and purifieation proeess design. We usedonly vapor phase cireulation method to measure vapor-liquid equilibrium values of 1 ,4-Butylene glyeol and Di.ethylene glyeol at 6. 67KPa. Thermodynamie consisteney test was conducted with area test method, and theexperimental data of the binary system measured in our work passed the test. WLSON and NR’Tl activity coef.ficient models were respectively applied to correlate the experimental data. The results showed that these twomodels both had very small deviation from the experimental results, which can meet the separation require.ments of the process.
DOU Ming,ZHANG Yan,MI Qingbin,etc;
Abstract: As a new energy technology, the ground temperature air-conditioning has been the rapid development and applieation in reeent years. However, the dynamie equilibrium of groundwater system is very easy tobe broken because large-seale development and utilization, which can cause a series of negative elfeets. In or-der to assess the impaet of different layouts for the groundwater, Anyang as the research objeet in the paper, anumerieal model of groundwater is established. There are three layouts, which are 1 to 1, 1 to 2, 2 to 3 forground temperature air-conditioning system. The simulation analysis is done for groundwater llow field andtemperature field with ground temperature air-eonditioning system. The simulation results show that there is agreat inlluenee for groundwater llow field and temperature field in reasonable proportion and layout of the pum.ping and injection wells, the most suitable layout of the region is 1 to 2.
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