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Abstract:

Abstract: Through the experiments of eight FRP-eonerete-steel tube eomposite square columns subjeeted toeyelie axial compression, the effeets of the loading scheme, the void ratio and the diameter-to-thiekness raticof the inner steel tube on the axial compression behavior were investigated. The test results show that the elffeetof loading seheme on the axial stress-strain envelope and peak load is insignifieant, and ultimate state of FRPconerete-steel tube composile square columns subjected to eyelie axial compression is very similar to that olcomposite square columns subjeeted to monolonous axial eompression. Compared with the void ratio , the diam.eter-to-thickness ratio of the inner steel tube has apparent inlluenee on the peak load of FRP-conerete-steeltube composite square columns subjected to cyelie axial compression.

Abstract: Based on silty sand roadbed of Zhengmin( From Zhengzhou to Minquan)Expressway Kaifeng see-tion, the DCP, long rod penetrometer and field CBR point comparison test was perfored and on three kinds ofmeasured data eorrelation is studied. Finally ,the relationships among DCP, long road penetration instrument,field CBR values was established. The results show that good correlation exists between the three test methods.and use the DCP, a long rod penetration instrument technology for rapid deteetion of silty sand roadbed qualitlycontrol is feasible method, and also can be useful referenee for practical use.

Abstract: The road disease in permafrost regions is related to the thawing deformation of the underlying per.mafrost, as well as to the weakening the embankment strength caused by freezing-hawing eyeles. In this stud.y, in order to investigate the inluenee of freezing-thawing cyeles on the strength of coarse-grain fill, the inllu.enee of freezing-thawing eyeles on the modulus of resilienee of coarse-grain fill with dilferent water contentswas studied with laboratory experiments. The results showed that, both freezing-thawing eyeles and water con.tent weakened the modulus of resilienee of eoarse-grain soil, which could not be negleeted. With the inereaseof water content of coarse-grain soil, the modulus of resilienee did not deerease rapidly, the reason of whichwas related to the frame slructure formed by coarse grain.

Abstract: The dilferenee of physieal properies between biodiesel and diesel has impact on the spray charae-teristies of diesel engines. In this paper, diesel and biodiesel made from soybean erude oil were blended indiferent proportions. The physical properly indexes of blended fuel such as density , kinematie viseosity, sur.laee tension and distillation temperalure were tested. Meanwhile, spray charaeteristies of biodiesel and diesewere measured in amosphere environment by sporls cameras and Malvern pariele size analyzer. The resultindieate that the density, kinematie viseosity, surfaee tension and distillation temperature of biodiesel are high.er than those of diesel. The spray eone angle of biodiesel at different time is less than that of diesel. Converse.ly, penelration distanee is longer than that of diesel. Compared with diesel, biodiesel’s Sauter mean diameterand representative diameter inerease. Simultaneously , the curve of drop size distribution and aecumulative vol.ume distribution shifl to the direetion of large particles, which indieates that atomization quality of biodiesel ispoorer than that of diesel.

Abstract: To explore the distribution of internal foree in pavement struetures on stone roadbed, the model wasbuilt. The strueture is made up of4 em AC-13 +6 em AC-20 asphalt surlaee course, eement eonerete, gradedgravel, graded broken stone leveling layer, basement layer of cement conerete and ATB-25. Based on themodel, the elleels of subgrade modulus on tensile stress and shear stress were studied. Results show that changes of subgrade modulus have litle elfeet on pavement strueture stress. Commonly, compressive stress only exists inside the pavement strueture layer. Tensile stress inereases gradually with depth , and tends to zero final.ly. The tensile slress easier appears in the cirele center of load, but it is less. The compressive stress is moreprone to generation at the edge of load round; then, the tensile stress appears in some depth with a bigger value. Shear stress inereases with the loads, and suddenly drops in certain depth; then, gradually it deereasesand tends to be slable.

Abstract: In view of the simply supported hollow slab common diseases,such as horizontal contaet due to thelack of hollow slab delleetion inereases , single plate bearing and other problems, with the finite element soltware ,a simulation study was carried out for the hollow slab bridge ,extemal prestressing steel reinforeement olthe. Change of displacement of strueture before and after applying transversely prestressing assembly type hol.low slab bridge through eomparison and analysis ,to analyze the elleet of reinforeement theory ,and diseusses thetransversely prestress ean improve the whole bridge. The beam boltom transversely preslressed reinforeementfor assembly type hollow slab is verified , transversely load distribution cean improve elfeetively ,inerease the hol.low plate struclure of transversely eonneetion ,thereby reducing the phenomenon of stress of single board.

Abstract: This paper focuses on dangerous rock body of Yonglan expressway. The author studies causes of thedangerous rock disasters of highway slope and puts forward suggestions for disaster prevention by means of fieldinvestigation and theoretieal analysis. lt also identilfies the disaster-causing environment of dangerous rock masson the north side of Heyetang viaduet, and analyzes topography , meteorology and hydrology , lithology , geologieal structure, hydrogeologieal conditions, ete; it also finds out the reasons for disasters by field survey: thestudy shows that the conditions of formation lithology and geologieal structures are main factors affecting the de.velopment of dangerous rock mass; disaster prevention measures against the dangerous rock mass of “ bolt an-choring + drainage + linked network prolection" are put forward through mechanies caleulations. The re-seareh provides a basis for disaster prevenlion of highway engineering.

Abstract: The black pollution of waste tires around the world has exerted large stress on environment. Themixtures of clay, cement and waste tire granules have so many advantages, such as light quality, high strengthand toughness, good seismic resistanee and impermeability ete. , which ean be used for coating material olbank or slope to reduee eraek and deformation. There are some triaxial testes on strength properties of mixturesoil and influence of waste tire granules. Test results have shown that the properties of clay mixed with litlecement and some waste tire granules can be improved greatly and shear strength inereases obviously. The criti.eal value of the tire granules is about 20%6 wih the cement content being constant, when the cohesion and thestrength ofthe mixtures can reach the maximum.

Abstract: To meet the requirements of roeket sled rails preeision fine-luning measurement, a method based onlaser tracker to precision measurement track geomelry was proposed. The method based on laser tracker to de.teet traek geometry deviations with the slide eontrol network Cpll points as measurement referenee point, u-sing conversion prineiple of spherieal coordinates conversion to spatial Cartesian coordinate system and differ-ent spalial Cartesian coordinate system conversion based on Bursa, proposed to convert the laser tracker systemcoordinates into orbit spaee coorlinates method, and the method was applied to a rocket sled test rail fine-tuning measurement. The results show that this method can meet the design requirements of rocket sled test slidefor fine-luning measurement, and the proposed testing the rocket sled test rail geomelry based on laser traekeideleetion technology is promising for track geomelry fine-tuning measurement of rocket sled test slide rail andhigh-speed test railways with an high elficieney and high aeeuraey statie measurement techniques.

Abstract: The CFD method was applied to investigate the preformanee of heat transfer and fluid fow in spiral.ly inner finned tubes with different baflle spaeing, spiral angle, and fin height for 27 different groups combina.tion. The numerieal simulation results show that deereasing balle spacing can improve the performanee of healtransfer on shell side. However, the pressure drop of fluid flow inereases with deereasing of balle spacingBut the performanee of heat transfer inereases greater than the pressure drop dose with Reynolds number inereasing, and the enhaneed tube has better performanee compared with the smooth tube. With the fin heighiinerease, the comprehensive perormanee of enhaneed tube inerease more obviously at high Reynolds numberregion. The formulae of heat transfer and fluid flow are fitted and the comprehensive perormanee of the en.haneed tube is evaluated.

Abstract: Abstract: Thermoeleetrie materials Ca3Co4O9 doped with Y in the composilion of Y0.2Ca2.8Co4O9 were prepared by sol-gel method combined high - pressure compacting technique followed by pressureless sinteringThe mierostruetures of the oxides were investigated and the eleetrical properies ( including of Seebeck coelfieient and eleetrieal conduetivity) were measured from room temperature to 1000 K. lt was found that highpressure compacling helps to improve the density and texture of Ca3Co4o9 . The eleelrical resistivity deereaseswith an inerease of temperalure, while the Seebeck eoelficient inereases with an inerease of temperature. Themaximum power factor 3.9 pW/emK2 at 973K is obtained for the sample pressed by high pressure.

Abstract: By means of tests, this paper verified the aceuracy and feasibility of a combined separator which akey projeet develop based on PDPA. The results showed that the combined separator efliciently realized muli.stage gas-liquid separation, and the separation efficieney of the combined separator was got through tested par.ticles size of export , liquid water content of import and export. By means of multiple data test method, the re-lationship between the input parameters and the gas-liquid separation efficieney, the input parameters and theoutlet LWC, the input parameters and outlet diameter was established by using the combined separator.

Abstract: Natural resourees of halloysite nanolubes and chitosan were used to prepare CiS/HNT hybrid por.ous beads with reversed-phase cross-linking and freeze drying technique, using glutaradehyde as a cross-linkerand ’Tween80 as the emulsifier. The hybrid beads were charaeterized by seanning eleetron microseope(SEM). The SEM image shows that hybrid bead is a porous structure comprised of chitosan and aceumulatedhalloysite nanolubes. The CTS/HN’T porous beads were used as adsorbent to remove anionie dye of methyl or.ange ( MO ) from aqueous solution. The elfeet of pH , MO initial eoneentration and eontaet time were investigated. The adsorbent exhibited good stability, relatively high adsorplion eapacity and eould maintain high remov.al efficieney of above 88% afer 10 times of cyclie utilization.

Abstract: In view of the uneertainty characteristies of heating nelworks leakage fault, such as randomnessfuzziness and variability, traditional fault-diagnosis method can not adapt well to the demands of heating net.works seeurily moniloring. Adaplive neural-fuzzy inerenee system ( ANFlS) eombines the adaplive and learn.ing capabililies of neural nelwork and the transparent knowledge representalion of fuzzy system. This paperpresents a two stage leakage fault diagnosis model of heating nelworks based on adaplive neural-fuzzy infereneesystem, which can diagnose the leakage pipe and rate and loeate the leakage point, aecording to the changesin the pressure of all nodes of the heating network. A comparalive example has been given wih the BP neuralnetwork. lt is shown that the ANFlS model provides high diagnosis accuracy and stability results.

Abstract: A clean diesel fuel additive is got by transesterilieation, which name is earbonie acid, 2ethoxyethylmethyl ester, which raw materials are dimethyl carbonate and glyeol ether, and which catalyst is KOH . itsstrueture is characterized by IR, 1HNMR, 13CNMR ,refraetive index and so on ,and the results show that thesynthetie material is the target product. lt is sludied the elfeets of some factors on the reaction ,which ineludesthe molar ratio of dimethyl earbonate and ethylene glyeol diethyl ether, the type and amount of the catalyst andthe reaetion time. The Optimal reaction conditions are (the datum is 0.05mol glyeol ether)as follows: n( dimethyl carbonate ): n ( glyeol ether) is 4: 1 , the quality of KOH is ten pereent of the glyeol ether, the rangeof the reaction temperalure is 90 degrees to 105 degrees ,the reaetion is continued for 3 hours. Under the aboveconditions, the average yield of Carbonie aeid, 2 ethoxyethyl methyl ester is 76.7896 with 3 parallel tests.

Abstract: A qualitative method to determine eyelohexylbenzene content in alkylation reaclion solution cata.lyzed by ionie liquid was developed, with gas chromatogram and n-deeane as interal standard material. Thecorrelation coellicient of standard curves of benzene and eyelohexylbenzene are both more than 0. 999. The analysis result shows that the relalive devialions belween real values and measured values of benzene and cyclyhexylbenzene are less than 5.2%6 , recoveries range from 97.96 %6 to 105.13%, and precision are 1.60%and 1.62% ,respeclively, which shows high stabilily and reliability.

Abstract: To salisly the sensorless veclor conlrol perlormanee lor permanent magnel synchronous motor(PMSM), a sensorless control method based on oplimal adaptive CDKF algorithm applied on nonlinearPMSM’s parameters estimation is presented, which is based on Bayesian oplimal estimation frame and seeond.order Stirling polynomial interpolation approximation method to determine Sigma points and its weight eoellicient, and meanwhile the stalistical charaeteristies changing over time of the system and measurement noisesealeulated adaptively. With the ACDKF algorithm and the current signals of the PMSM under complieated conditions it ealeulates the speed and magnet angle displacement, then the speed and magnet angle displaeementof veetor eontrol system are obtained. The simulation data demonstrate that the proposed method has belter estimation precision and computation elicieney and numerical stability than others CDKF algorithms.

Abstract: In this paper, we propose an opportunistie spectrum sharing ( OSS ) algorithm with quality-of -service ( QoS) support to coorlinate the spectrum aecess of primary users ( PUs) and secondary users ( SUs)for cognitive radio nelworks ( CRNs). We also analyze its performanee in the presenee of two secondary users(SUs) groups with different terminated-priorities and aeeess-priorities, which are defined to saisly differenlQoS requirements of SUs. In addition, we use a six-dimensional Markov approach to derive system perform.anee , such as SU foreed termination probability, blocking probability and system throughput. Numerieal re.sults show that the QoS requirements of dilerent SUs can be guaranteed in the presence of guaranteeing thecommunieation quality of PUs, and the system throughput is signifieantly improved compared with other typieaspectrum sharing schemes.

Abstract: Reaclive power oplimizalion problem is a muli-bound, muli-variable mixed integer programmingproblem, and the operating variables inelude continuous and diserete variables, so the optimization problembecomes complex. In view of the diserete charaeteristies of and compensation capacitor sets, this paper adoplsa simple and practieal approach, an auxiliary funetion is structured to express the input or withdrawal of capae-itor sets. This method transorms diserete variables into continuous variables. The oplimal objeetive is to mini.mize the competitive expenses of power loss and the cost of equipment regulation. Variable metrie algorithm isadopted to solve the oplimal problem. Proposed approach is examined on one system ; eomputed results providethe active power losses and capaeitor states. The proposed approach is examined in one testing system.

Abstract: In the modulation classilieation of MOAM signals, clustering points based on traditional clusteringalgorithm is nol aeeurate. The number of iterations of the algorithm is more and the error sum of squares fune.tion curve is not smooth. To solve this problem, this paper presents a MOAM signal modulation recognitionmethod based on semi-supervised clustering theory to reeonstruet signal constellation diagram. By markingsome sample points to guide the membership and updates of the cluster centers, combined with SVM classifiea.tion , the different levels of MOAM signal’s reeognition are realized. The simulation results show that the algo.rithm for MOAM signal recognition rate is greater than 90% , has less iteration and the error sum of squaresfunclion curve is smooth.

Abstract: To solve the problem that the study of the capaeity in distributed networks was consirainted in thesingle hop case, a strategy of selecling relay was proposed to analyze the random aeeess transport capacity inthe distributed networks with multi-hop ease, by using which the transmitted data would arrive at the final re.ceiver within finite hops, and the expression for the random aeeess transport capacity was derived. Numeriealand simulation results showed that the random aeeess transport eapacity inereased with the maximum probabili.ly of outage, and inereased with the lransmission distance.

Abstract: This paper addresses the network selection problem in Cogniive Radio Networks( CRNs) based onprice and 0oS requirements. Evolutionary game is used to model the nelwork seleetion problem in our paper tochoose the best aeeess nelwork for all users to maximize the revenue of the nelwork. Based on our model, ourwork took some 0oS requirements into aeeount and proposed an algorihm based on price and users’Qos re-quirements. Simulation results show that our algorithm can eapture the main faetors in network selection inCRNs and oblain a belter performance in a more realistie system.

Abstract: The Environmental Eeonomie Dispateh ( EED) model integrating wind power is established. TheMulti-objeetive Evolutionary Algorithm based on Deeomposition ( MOEA/D) is proposed to solve the modelwith the constraint handling methods, normalization and mutation operation to improve the perormanee of thealgorithm and maintain the diversity of solutions, which ean obtain the ideal Pareto oplimal front. Simulationtesls were perlormed and the results show that, through comparative analysis with other oplimizalion algorithms.the MOEA/D is more feasible and effective in solving EED problems with wind power.

Abstract: A struclure plan is raised about hydraulie manipulator for viseose staple pulp feeding machine feed.ing oecasion. Funetions of locating, reelaimering, settling, finishing down stockpiles, lifting, feeding and oth.er funetions can be realized. Feeding eage as core component and main stressed member of feeding manipula.tor, so copper bush getling the largest torque is performed Mises stress analysis when main body and supporttube of cage reached the limit position. The analysis results show that the maximum stress fits the preseribedlimits and all data are conform to requirements. Further oplimization is performed about the sulfered maximumstress site on the basis of above results. "Theory basis is obtained and used for the development of hydraulie manipulator of pulp feeding machine.

Abstract: High resolution range profile ( HRRP) contains abundant target strueture information, and is widelused in radar automatie target reeognition ( RATR) area. Traditional Bayes classifier or kernel classifier basedreeognition method suffers from the model - data mismateh or huge computational burden. To solve this prob.lem, a random forest ( RF) based HRRP recognition method is proposed. Both the prineiple and algorithmproeedure of RF are introdueed in detail. Experimental results based on simulated data show that RF is superior in recognition perormanee and computation elficieney compared wih Baves classifier and kemel classifer.

Abstract: By means of intersection of covering, two kinds of eovering rough set models are delined in the easeof absenee of equivalenee relations in addition to covering relations between the data elements. The properiesof lower approximation operator and upper approximation operator are diseussed by using comparable methodsin two covering rough set model, and the correetness of the corresponding point is proved by using mathematieal theory. Through analysis of the delinitions of two kinds of covering rough set models, the relationships olthe lower approximation operator and upper approximation operator and with other rough set models are illustra.ted. Through these researches, the rough set theory is expanded, the theory and method of knowledge diseovery is improved, and a simple way is provided for data mining of large databases.

Abstract: The hybrid eleclrie bus with the new general arrangement causes the vehicle sruelure changes.Considering that the kinematie charaeteristies of the suspension system has the exlremely important inlluenee tovehicle handling stability, on the basis of multi-body dynamies theory by using the ADAMS/Car software, theresearch on modeling and simulation of the independent front suspension of a hybrid eleetrie bus is perormedand the change rule of the main wheel alignment parameters along with wheels beating stroke about molioncharacteristies was analyzed. lt turned out that the properlies of alignment parameters of front wheel on the hy.brid eleetrie bus are close to these of the original vehicle, and meet the requirements of design , which providesa theorelical basis for real vehiele researeh and development later.

Abstract: In order to obtain the saueer-shaped lifting body’s flow filed fealures and development law, theeomputational fluid dynamies method was taken to simulate the saucer-shaped lifing body’s flow field, as wellas its stalling characteristies. "The simulation was validated by the wind tunnel experiments. The simulation re.sults show that the saucer-shaped lifing body’s llow field has a steady vortex structure , bring a signifieant vor.tex lift, which inereases with the inereasing of altack angle. The vortex lift to tolal lift ratio is 8%6 when the attack angle is 4°, and the ratio is 30%6 when the allack angle is 40°. The stalling angle of the saueer-shapedlifing body is 40°, which is beller than the conventional aireraft.

Abstract: On the basis of the working principle of a new hydro-pneumatie pile hammer impactor control system, we made the dynamie modeling for its impactor system piling process. Finally, each dynamie modeling issimulated and analyzed with Matlab soltware, and the result of simulation research is helpful for improving andoplimizing key design parameters of pile hammer impactor system.

Abstract: In order to study the cooling proeess the temperature field ealeulation and analysis area first, andthen temperature field results data in the form of temperature load in structure analysis. Utilizing the general finite element analysis soltware ANSYS thermal stress forming proeess of TC4 titanium alloy droplets depositionchanges are simulated. Based on the parametrie design language APDl of ANSYS finite element analysis model, adopt the way of indireet coupling simulation of the thermal stress, the researeh on muli - laver droplet in.ternal residual stress distribution alter cooling to room temperalure , and a new layer when the droplet drips andoriginal cooling region has been completely between the residual slress distribution. The result shows that thefinished temperature diflusion degree of molten droplels is small in the equivalent temperature from differenttime ; Afer a period of time after cooling, heat from the droplet area to have the cooling area, temperature fur.ther proliferation ; The last is close to room temperalure. From the verieal and horizontal analysis of stress andstrain , lt can be seen the subsequent droplet drip area middle sag down , eontraction deformation emerge. Between different lavers in horizontal direetion, the temperature differenee is small. The stress distribution ismore uniform at the lale overall cooling.