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Abstract: A numerical simulation of trisection-ellipse heat exchangers with helical baffles is carried out， andthe helix angles are 15° and 20° respectively ， and we studied the impact of triangle leakage between continu-ously overlapped and adjacent baffles on heat transfer and resistance performance of heat exchangers.Throughthe comparative analysis about the simulation results of existing triangle leakage and that of blocking trianglearea without leakage , the results show :triangle leakage makes a more serious short circuit flow for the shell-si-ded fluid;Triangle leakage makes heat transfer coefficient，shell-sided pressure drop and comprehensive per-formance of heat exchanger reduce. When triangle leakage is blocked，heat transfer coefficient increases by8.5% ~ 11% , shell-sided pressure drop increases marginally , comprehensive performance increases by 8.1 %~11 . 1 % .

Abstract: In order to enhanee conveclive heat transler of the heat transfer tubes with bigger diameter, a newkind of tube insert, spiral grid twisted tape, was developed for the gas-fired vacuum boiler. 3D geometricmodels of the spiral grid twisted tape and the classie twisted tape with the same twist ratio inserted the tubeswere sel up repeelively. The comprehensive heat transfer charaeteristies in the tube was simulated using theFlUEN’T sofware under the same conditions. The mechanisms of heat transfer enhancement, such as deereasement of hydraulie diameler of flow section, inereasement of spiral flow speed, the secondary llow causedeentrifugal foree ete. are analyzed. The results show that the conveetive heat transfer coefficient of the spiragrid twisted tape deereases 8.6% than that of the classic twisted tapes and pressure drop decreases 32.0%.and comprehensive evaluation factor J is greater than 1. lt shows that the spiral grid twisted tape has a goodcomprehensive heat transter perermance.

Abstract: Flow and heat transfer charaeteristies of convex eorrugated tube, coneave corrugated tube and bel.lows corrugated tube are studied, based on the k-s model with numerieal comparative method, the flow andheat transfer performanee with the changes of Re is obtained; The heat transfer mechanism and the resistaneemechanism are analyzed, the main eauses of loss in heat transfer and pressure drop are detected. The perform.anee of the corrugated tube is analyzed in heat transport potential capacity( Entransy), and the entransy differenee , AE, belween inlet and outlet with the changes of Re is acguired.

Abstract: In this paper, the ( Sm0.5La0.2)2Ce2O2 ceramie was synthesized by solid reacion using La2O3, Sm2O3 and CeO2 as raw materials. lts phase composition mierostruclure and composiion was analyzed by X-raydillraetion, seanning eleetrieal mieroseope ( SEM) and eleetronie difraction spectrum ( EDs), respeetively.Its thermal diffusivity and thermal expansion eoellicient are measured by laser flash method and pushing rodtechnique. Research results show that synthesized ( Sm0.5La0.2)2Ce2O2 ceramie has single fluorite structureand dense mieroslruclure. No other phase or un-reacted oxides exist in the interlaees between grains. lts loweithermal conduelivity and higher thermal expansion coelfcient can be attributed to the La-doping.

Abstract: SAPO-56 moleeular sieve was hydrothermally synthesized with N, N ,N’,N’-tetramehtyl-hexane-1 ,6-diamine ( TMHD) as template agent. The effeets of siliea alumina ratio, propylamine parlly replacing template, and seeding in synthetie system on morphology and size of SAP0-56 were investigated. The resultsshowed that pure SAP0-56 phase with similar erystallinity could be obtained under the experimental condi.tions. With the inerease of siliea alumina ralio, the morphology of SAP0-56 synthesized changed from hexa.gonal llake to disk, and the erystal size was about 20 pm. Propylamine partly replacing the template agenlcould deerease the erystallization time, and the synthesized SAPO-56 changed to thick culter top hexagonal.dipyramidal, but the erystal size showed little change. Further seeding into the synthetie system the SAP0-56changed to hexagonal-dipyramidal, and the erystal size deereased significantly to about 3 um. So the morphology and crystal size of SAPO-56 could be adjusted by changing experimental conditions.

Abstract: The adsorption performanee of pyrolytie carbon from riee husk modified with CaCl, soaking and mi.erowave heated method for aniline from aqueous solution was studied. The experimental results showed thamodified pyrolytie carbon ( MW.PC) exhibited larger adsorption eapacities than unmodified pyrolytie carbon(PC) for aniline. "The adsorplion isotherm of aniline followed the Langmuir model and the maximum adsorption capaeity was 0.623 mmol/g at 298K. The adsorplion of aniline was a process of spontaneity, enthalpy in.erease and enlropy inerease. The experimental data followed the pseudo-second-order kinetie model. The besdesorption reagent for saturated MW.PC with aniline was absolute ethyl aleohol.

Abstract: Extraclive distillation process for separating toluene-N-heptane mixture was simulated by using Aspen Plus proeess simulation soltware and NR’Tl model. Phenol was chosen as the extractant. The elffeets of ma.jor design parameters,such as theoretieal tray number of extractive distillation column,extractant feeding position, material feeding position, rellux ratio, mass ratio of extractant and feed( solvent ratio) and extractantfeeding temperature,on the separation were invesligated. Aimed at the N.heplane mass fraetion of 99%6 andthe reeovery of 9996 in the produet, the oplimal proeess conditions were theoretieal tray number of exlractivedistillation eolumn of 24, extractant feeding posilion of the 6th tray,the mixture feeding position of the 14thtray, rellux ratio of 5.8, solvent ratio of2.5. Under the conditions ,the N-heptane mass fraetion and reeoveryralio in the prduct reached 99.4% and 99% respectively.

Abstract: Fire dynamies software FDS6 is used to simulate the seenarios of tunnel fire , the temperature distribution of the plume and the maximum temperature of plume impingement zone under the aetion of longitudinalwind are obtained with different fire power. With a new turbulent combustion model, the results of FDS6 showthat the high temperature zone of fire souree foeus on the boltom of plume and a considerable part of plumeheat transfer to ambient by thermal radiation. The heat transferred by eonveetion in plume is redueed, and thetemperature of the plume impact region under tunnel ceiling is obviously lower than the results of FDS5. Themaximum temperature of plume impingement zone under the aetion of longitudinal wind obtained by FDS6 issignificantly lower than the Kurioka model predietions and the tunnel fire experimental values.

Abstract: Nilrogen souree is an imporlant raw material lor the production of 1 ,3-propanediol fermentation, ni-trogen eoneentration in the medium direetly inlluenees the fermentation results, from the choiee of nitrogensouree and adding mode, research the use of a variety of organie nilrogen and inorganie nitrogen, the elfeet oladdition on fermentation. Through the sudy, the pure organie nitrogen sourees can nol appease the demand olPDO production, while the corn steep powder 3.0 g/l as organic nitrogen souree can be used in industrialproduetion elfeetively instead of yeast extract. With the compelement model of uniting the PH value controlmodel, the final content of 1 ,3-propylene glyeol glyeerol was inereased to 72.5 g/L.

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Abstract: After a sludy of the classieal clustering algorithms such as ETBG, a clustering topology algorithmBased on Uneven Gradient in WSN was proposed. This algorithm not only uses analytical hierarchy Proeess todetermine the coeflieient of each faetor, but also improves cluster members choiee slrategy based on the idea oluneven gradient, thus the cluster heads closer to the base station can preserve some energy for the inter-clusterdata forwarding. Simulation experiments demonstrate that this algorithm provides an efficient solution to copewith the energy hole problem and prolongs entire network lifetime.

Abstract: This paper presents a new algorithm based on fountain code to improve robustness of the watermarkin digital image watermarking system. Employing the outstanding performance of LT codes in erasure channelthe proposed scheme combines channel coding with spread speclrum watemarking to reeover watermark. lnthe end, this paper makes a series of tests with fountain coding scheme and LDPC eoding scheme and non coding scheme, the result shows the scheme proposed in this paper can raise robusness of the digital watermarking system , lower the bit error rate ( BER) between watermark and reeovered watermark effectively. In addition , fountain coding scheme has lower complexity compared with LDPC coding scheme.

Abstract: The disappearanee of self-mixing interlerenee fringes in the high feedbaek-regime decreases thelisplacement measurement aeeuraey. The proposed method based on Lang-Kobayashi equation deteets thefringe-loss with a large oplical feedback faetor C. And the relationship between C and m which represents thenumber of fringe-loss in half cyele is oblained: C<4.6,m=0:4.6≤C<4.8,m=1:4.8≤C<7.9.m=2. Aself-mixing interferenee displaeement measurement algorithm is presented that is able to remedy the inllueneeof fringe-loss. The measurement accuraey is improved greatly.

Abstract: With the development of the society and the progress of seienee and technology, the Internet ofthings technology by leaps and bounds. The new coneept of Intelligent Medieal is becoming more and more ae-cepted by people, but there are sill the problems of clear network architeeture, real-time transmit data. In or.der to solve these problems, the intelligent Medieal System based on Android Platform was developed. Thissystem monitors the vital signs of body through the sensor nodes on the body, ineluding the blood oxygen satu-ration, body temperature, pulse frequeney, and transfers the data to the Android mobile client for display andanalysis through gateway. The experimental results show that this system network architecture is good and canachieve the goal of the real-lime data lransmission.

Abstract: Aiming at the realistie need of shadow rendering, on the basis of the PCSS algorithm, this paperputs forward a solt shadow generation algorithm based on GPCPU. lt samples a region by poisson disk patterninstead of regular sampling mode, uses depth gradient to deal with the phenomenon of self-shadowing, uses theVSM algorithm to filter the shadow, and uses the summed area table to filter the shadow map dynamieally,which can improve the shadow qualily and rendering efficieney in a certain extent.

Abstract: The feature points matching image mosaie algorithm was found to be sensilive to rolations andnoise , and an automatie image mosaie method based on SURF and Pseudo-Zernike moments algorithm was pro.posed. The improved SURF feature points detector was used to get the comers, then the pseudo-Zemike mo.ments defined on the interest point neighborhood were eomputed. Through comparing the Bray-Curtis similaritymeasure of the pseudo-Zernike moments to extraet the initial feaure points pair, then the spurious featurepoints pair were rejeeted by RANSAC algorithm, then by means of using the geometrie transform of input ima-ges for registration, the overlapping region of two images was fused and the image Mosaie was finished. lm-proved SURF feature detection algorihm extraet feature points are uniform, aeeurate and fast. The proposedmethod of image registration is robust to rotation , lranslalion and noise.

Abstract: Based on the quasi-static test study of seismic performance of HRB500 reinforced concrete piers ,influence law about steel strength ，the spacing，the axial compression ratio on seismic behavior was obtainedaccording to the analysis of its failure characteristics, hysteresis curves，skeleton curves，stiffness degradationunder low eyclic loads. The results show that increasing steel strength can improve components’ bearing ca-pacity and deformation capacity obviously , stirrup ratio can not influence members’ bearing capacity and de-formation capacity ,axial compression ratio can improve components’bearing capacity , but on the other hand,it is useless to improve components’deformation capacity.

Abstract: Aiming at the application of epoxy asphalt in concrete bridge pavement, epoxy asphalt was prepared. The effects of different resin content on viscosity, high and low temperature properties of epoxy asphalt bond, mechanical properties, low temperature crack resistance and high temperature stability of epoxy asphalt mixture were studied.The results show that the addition of epoxy resin can improve the road performance and mechanical properties of asphalt mixture. With the increase of the addition amount, the curing reaction process of epoxy asphalt is accelerated, the high temperature performance and fatigue resistance are enhanced, the stiffness modulus is increased, the creep rate is decreased, the low temperature crack resistance is decreased, and the fatigue resistance and high temperature stability of asphalt mixture are improved.By comprehensive analysis,30% is the best dosage of epoxy resin.

Abstract: The seeurity issues of construetion steel treslle and sealfold platforms for the eross channel bridge ofYangjiang nuclear power under the coupling aetion of the typhon and wave loads are researched. The finite el.ement model about construetion steel trestle and seaffold platforms is built with ANSYS software and the me-chanieal behavior is ealeulated. The results show that the stability of the platform and the strength of the steelpipe pile meet the requirements under three kinds of loading eombinations. Under the eombined effeet of theextreme wind and wave forees , the deformation of the platform is not too much, but the support of both sides olthe steel pipe pile is not enough and the stability is worse.

Abstract: In order to estimate vehicles inventory in high resolution at a mieroseopie seale region, the MOVESmodel of US new version was introdueed and the sensitivity of three tralfie condiions parameters was analyzedTaking a typieal signal interseetion as research objeet, the operalion modes relleeting vehieles running charaeteristies in interseetion were gained through field measurement and statistieal analysis. In eonsideration of timing weight in the different direetions, the PM2.5s and CO inventories of typical intersection were ealeulated byMOVES model. Lastly, the effieieney of compressed nalural gas ( CNG ) in the reduetion of PM2.5 s and CO wasmodeled when the buses conventional fuel was replaced by the altemative fuel (CNG). The results show that.the traffie emission evaluation based on operating mode can better relleet the realistie vehicles" operation na.ture more, and ealeulate out more preeise values. In the case study, the emission inventories of PM2.5 s and CO in the interseetion region were redueed by 66%6 and 596 respectively after the bus fuel of CNG was pulinto use.

Abstract: Based on praetical projeet, the ABAQUS numerieal analysis model is established. After the compa-ring study on numerieal analysis results and the field monitoring ones, the model and corresponding parametersare verified. Then, virtual designs are carried out, with different heights of soil nail wall, pre-stress forees olanchorage, and stiflness of pile. The adequate height of soil nail wall is no more than 6 m. lt shows that thepre-stress foree of anchorage has litle elleet on deformation control. On the contrary, the stillness of pile is vi.tal for delormalion conlrol in this style of soil retaining struelure.

Abstract: Based on the field tests of port road under the vehiele load, a series of numerieal simulation waseonduceted using FLAC3D to analyze the deformation charaeteristies of port reclamation ground under the vehi.ele load. The pavement is modelled by the elastie model and the ground is modelled by the M-C model. A de.tailed analysis of the additional stress and verlieal strain of ground is perormed. Simulation results show thatthe additional stress eoneentrates in shallow ground under the loading position and this phenomenon disappearsgradually along the depth. The vertieal strain of silt soil is larger than the other soil and it deereases slightly along the depth. Lastly, a series of parameters analysis was carried out, such as loading position, wheel pres.sure and sand cushion thickness.

Abstract: Prolective relay setting caleulation plays a very important role in the stability and security of powersystem. The paper has developed a protective relay selling calculation soltware system based on C# language tomeet the requirements of versatility, sealability and maintainability, which improves the speed and accuraey olthe selting caleulation. By using the modular architeeture and database, the paper develops open selting prin-eiples , proposes a super-pipelining low-blocking rate data aeeess technology based on generie type, applies thenon-revisiting breadth first search algorithm to generate zero-sequenee network diagram automatically and teststhe effecliveness of proposed algorithm on five-bus power system.

Abstract: To get belter used for the lPNC in biomedical and robolie systems, the position that we expeet mustbe controlled precisely. Against strong nonlinear properties and model uneerlainties,as a result, an lPMC ari.ficial museles position traeking eontrol system based on sliding mode variable strueture control and Pl controlapproach is proposed. First, the robust stability is achieved by sliding mode control, furthermore, slidingmode variable structure control and Pl control approach which are used to traee the position, finally, the pa.rameters of traeking eontroller are designed by using neural nelwork. The designed system not only can achieveposition tracking, but also guarantee stability in the presenee of elfeet of uneertainlies and exteral perturba.tion, the elfeetiveness of the proposed method is confirmed by simulalion results.

Abstract: Because FEM ( finite element method) cannot simulate a mass of shots impinging the target, theSPH( smoothed particle hydrodynamies) coupled FEM modeling and simulating for shot peening is presented.in which the shols are modeled by two types of SPH particles and the target is modeled by FEM and the twoparts interaet through a contaet algorithm. Combining with the random algorithm, the random model for sholflow is established and the state equations for shot flow are dedueed. The relationships between residual compressive stress and peening veloeity, peening time, and the residual compressive stress at typieal positions areanalyzed. The results show that higher veloeity ean eause deeper residual compressive stress under target’ssubsuraee. After a certain period of shot-peening, the residual compressive has harlly changed, of which themaximum residual compressive stress changes by less than 1096 . The residual stress at the center of impinge.ment reaches the maximum.

Abstract: Heat dissipation capacity of eleelronie equipment inlluenees not only its stability, but the servicelife of the components. E’speeially in the high-altitude area with thin air and low air pressure, heat dissipationperformanee is more likely to deteriorate in closed chassis. In order to study heat dissipation problem of elee.tronie equipment at the high altitude, based on the turbulenee theory, eooling flow mathematieal model olchassis was established. By means of lCEPAK, an eleelronie thermal design specialized soltware , the heat dis.sipation of different altitudes were simulated. The theory that two-equation turbulenee model for eooling ealeu.lation in thin air area should be more aeeurate, was put forward and verified through the simulation. This willprovide a referenee for the thermal design of eleetronie equipment in high altitude areas.

Abstract: Reliculated shell strueture is characterized by simple configuration, the internal foree distribution e-venly, easy to manufacture and assembly, and so on. Aeeording to the prineiple of network shell configura.tion ,a method for single spherical shell configuration of network design was proposed based on CAGD, throughwhich the unneeessary rounding errors brought by conventional computational modeling proeess could be elffee.tively avoided and the complete symmelry of network shell modeling was achieved. Through the research ol240 body surfaee monolayer shells modeling, we analyzed the impaet of rod length ratio with diameter and rola-tion angle of pentagon on the rod length and eventually obtained the conditions of rod length uniformly.

Abstract: Based on a cerlain chassis, an all-wheel steering system is designed by improving its steering sys.tem which is drove by hydraulie power. A three-DOF mathematical model is built for the vehicle and an opli-mal controller is designed for the steering system. "The oplimal eontroller is simulated through this model, com.paring the side-slip angle, yaw rate, body roll angle and body roll angular velocity of the vehicle with the original steering system. The results showed that all-wheel steering system can improve the maneuverability of ve.hicle at low speed and maintain the stability of vehiele at high speed. The results laid a foundation for the de.velopment of all-wheel sleering controller.

Abstract: The comprehensive competitiveness of a logisties park rellecls its ability to survive and progress.Taking into aecount several factors about a logisties park, such as the infrastruclure, the operation manage.ment, the regional transportation , the poliey environment and the development of the hinterland eeonomy, thispaper establishes evaluation index system of the comprehensive compelitiveness. The proposed evaluation mod.el use the AHP and TOPSIS. Finally, the empirical analysis is presented.