2017 volumne 38卷 Issue 02
Jiang Dongxing1,Wu Haiyan2,Yuan Fang2,Fu Xiaolong2
Abstract: With the deepening application of emerging information technology in education business,the information technology performance-oriented,focus,construction and operation mode has begun a major change,and the informatization in universities has entered the stage of wisdom campus.This paper analyzes the key factors that affect the construction and application of the wisdom campus,and based on this proposes the maturity model and its evaluation index system to guide the orderly evolution of the wisdom campus.
Long Xinzheng; Ouyang Rongbin; Li Ruomiao; Li Tingyan Wang; Qianyi
Abstract: Aiming at the shortage in content and technical aspects of campus mobile information service,this paper proposed a construction scheme of campus mobile information based on wechat public platform.The cture of the campus mobile information service architecture composed of 4 components:wechat public platform,unified identity authentication platform,mobile information service platform,and open service platform.And the core components was implement based on microservices.In additional,this paper solved the key technical problems such as user binding,webpage authorization,notice push and wechat payment based on advanced service API of wechat public platform.The campus mobile information service was widely concerned by the teachers and students,the total number of people reached more than 25 000,the number of binding users reached 15 000,the number of daily traffic was more than 2 000.
Jiao Baochen; Chen Shiming; Liu Zhenchang; Yang Yang; Zhang Sihai
Abstract: An increasing amount of attention was widely drawn to the Graduate Management Information system,which could be considered as an important means of the college graduate educational informatization.Currently,the construction of the graduate system was promoted in most of college.Nevertheless,it was deficient in the application effect evaluation of the graduate system.From the view of the practical application,a way of building the index system was proposed,which was according to the partition and application of the user.The evaluation index of the application effect with the double levels was constructed.The weight parameters were determined by analytic hierarchy process (AHP),through the expert evaluating method.As an example,the Nankai University was taken to proceed the application effect evaluation.The result showed that the application effect of the graduate system of Nankai University reached high level.A feasible project of the application effect evaluation was proposed in the Graduate Management Information system.Through the method of application effect evaluation,the application level could be estimated effectively and directly in the graduate system.Moreover,the indispensable suggestion could be presented for updating and developing the system.
Ouyang Rongbin; Liu Yunfeng; Long Xinzheng
Abstract: PRBAC was always implemented to achieve fine-grained access control.This paper analyzed recent research on data permissions,summarized related experiences,and presented a parameter model of PRBAC based on attribute rules.It presented the model’ s design,including the rule’ s formal form and its components.It also described a general implementation scheme,including the rules’ specification,rule’ s application time choice,algorithm of the rule’ s validation,and some key techniques of the implementation.With the practice on IAAA at PKU,it showed that the model was flexible and the rules’ setting was convenient.This paper also pointed out that rules’ conflict checking should be implemented in future.
Hu Yan, Zhu Xiaoying, Ma Gang
Abstract: Location prediction was critical to mobile service because various kinds of applications were tightly combined with user’s location.However,location prediction was a challenging work because location capturing was always not continuous and user’ s behavior were uncertain and irregular.To improve the location prediction accuracy rate,this paper proposed a location prediction model based on K-Means algorithm and time matching.For the mobile service always region oriented,we first clusted history location using K-Means algorithm to define several regions.Then we divided every day time into several segments and calculated the maximum probability location in every time segment.A trajectory of a user in one day was formed with trajectory model and trajectory updating model which proposed in this paper.We could predict user’ location with time matching method.At last,we did experiments with real location data in campus which captured by APs.The prediction out come with K-Means was compared to the outcome without model based on K-Means algorithm.The experiment result shows that accuracy rate of our model was higher than the prediction without new model.So,more location services could be provided to users with this new model.
Cao Yang
Abstract: In order to realize the harmonious development of high-speed railway station area and urban space,by analyzing the spatial variation characteristics at three levels such as site and the surrounding areas,cities,and regions,this paper classified the relationship between high-speed railway station and existing urban spatial form,and found the internal relations and mutual transformation between various urban spatial forms.The conclusion of the study was that the benign development of urban space under the guidance of high-speed railway station should combine unban elements,locate the function of high-speed rail station area reasonably,and evaluate the location relationship between station area and the original city center beforehand and so on.
Zhang Yunliang1,Zhang Zhicheng2,Yang Weichao1,Ding Minghong2
Abstract: Based on the three-dimensional unsteady viscous incompressible Navier-Stokes equations and the standard turbulence model,using the Fluent computational fluid dynamics software,the situation that the highspeed train intersected in tunnel by the same speed was simulated.Two CRH380HL of same shape were arranged to intersect in the tunnel at four kinds of speed to simulate the changing process of aerodynamic forces,and the data of internal and external pressures of train body was collected.Using the formula to calculate the interior pressure of train body,this paper presented the passenger comfort evaluation of different train speeds.
Zhang Shaonan, Qian Xiaodong
Abstract: The previous method in safety evaluation of urban traffic just proced part of the uncertain information,while the SPA (Set Pair Analysis) theory was able to process and describe all the fuzzification and indeterminacy caused by uncertain factors uniformly.This paper adopted SPA to evaluate the safety of urban traffic.Taking urban traffic system as the object,the evaluation was conducted in the following two aspects.Firstly,it was to build the SPA model of index weight and to analyze the weight of influential factors;Secondly,it was to group the actual targeted value and the standard targeted value into two sets,which were consequently formed as one set pair.Due to the different evaluation criteria,there might be several set pairs.By calculating the connection degrees of those set pairs,the grade with the highest connection degree would be chosen as the final evaluation result.The feasibility and actual value of this method were verified by instance analysis.
Yang Gaofei1,Xu Rui1,Qin Ming1,Zheng Kaili2,Zhang Bing1
Abstract: The traffic prediction was an important component in the intelligent transportation system.The effective short-term traffic flow prediction was conducive to ensure the intersection unimpeded and reduce the traffic delay.According to the uncertainty of road conditions and the nonlinear change of traffic flow,the ARMA model and kalman filter mode was combined through the error magnitude of predicting results to predict the short-term traffic flow in the road.The example indicated that the combined model could achieve the higher prediction precision and made the prediction accuracy up to 5.79 percent.Besides,the combined model had an advantage over the single model in the forecasting accuracy.The combined model can not only predict the short-term traffic flow more accurately,but provided the necessary theoretical basis and technical guidance for the intersection signal timing.Besides,it had definitely application value in reducing the traffic delay and improving the road service level.
Chang Yulin1,Wang Xiaoting2,Zhang Peng2
Abstract: In order to more quickly and accurately search for the optimal path,an improved ant colony algorithm was established through analyzing the process of car arriving and departure in the signalized intersection.First of all,a new pheromone update model was put forward by improving properly the pheromone update function in traditional ant colony algorithm,which used signal control delay in the intersection and the travel time of vehicles in the road section as pheromone update operators.Then,road section incremental allocation process considering intersection delays,which was through partial distributing traffic flow in the network,was designed based on improved ant colony algorithm.Finally,flow distribution in the road network was simulated based on computer language,and the network running quality was compared with traditional ant colony algorithm.The experimental results showed that the improved ant colony algorithm,which could reduce road section and intersection using rate,was of good optimization ability,and could effectively balance the network traffic and alleviate the pressure of intersections.
Li Aizeng1,Jia Junbo1,Zhang Yafei1,Li Wenquan2
Abstract: Reasonable organization of left-turn forbidden traffic flow could effectively reduce the left-turn vehicles delay through signalized intersection.There are barriers between two-direction vehicles,through the queuing and probability theory,the distance of two indirect left-turn modes from the road turn-around position to the intersection stop line was studied.To "right-turn,turn-around and through" mode,considering coordination-control or not for right-turn signal and intersecting-road through signal,the distance calculation model was established.To "through,turn-around and right-turn" mode,taking the two condition weather setting road median-opening signal to coordinate intersection signal into account,the distance calculation model was obtained too.To the "through,turn-around and right-turn" mode,when the coordination-control policy was adopted,the technique of "early-startup and early-stop" of road median-opening signal was put forward,and the calculation method of the time of "early-startup and early-stop" was put forward as well.The case study indicated that the indirect left-turn organization scheme was feasible,and had obvious effect on improving the operation of the signalized intersections.
Jiang Jiandong1,Du Yaoheng1,Yan Yuehao2,Bao Wei2
Abstract: At present,the phase measurement units were not sufficient for static state estimation in most existing power systems.A novel method was proposed to solve the problem in this paper.Realizing that PMU measurements were more accurate than SCADA ones,the proposed approach estimated PMU unobservable states and PMU observable states separately so as to expand the effect of PMU measurements on the result.For the PMU observable states,they were estimated by PMU measurements using a linear estimator.And the PMU unobservable states were estimated by conventional measurements in a reduced-order nonlinear estimator.When compared with conventional approaches the proposed decoupled method features reduced computational complexity and greater numerical stability.In the end,this method was verified that it had more advantages than weighed least square method and fast decomposition algorithm by simulations on standard IEEE test systems.
Liu Chang1,Zhao Junxiang2,Hu Hai3
Abstract: For the issue of motion estimation of underwater dynamic threat,single-stage estimation method is utilized extensively in which velocity is decomposed to three coordinate axes for independent calculation.In order to consider the integrity of the speed,a double Bayesian estimation method is proposed in this paper.In the first stage of the improved approach,the velocity and direction of underwater dynamic threat are estimated by the adaptive Bayesian estimation,and then the position is estimated by the unscented Bayesian estimation in the second stage with the joint efforts of the estimated results in the first stage.Simulation results are provided to verify the feasibility and effectiveness of the proposed method.
Dou Benjun1,Ji Yong2,Zheng Shanggao2,Feng Dongqing1,Rayong1
Abstract: In order to build 3D simulation model of transformer substation,the device should be indentified quickly.But the 3 D data of substation equipment was so large that it was difficult to identify quickly.This paper used dimension reduction to reduce the amount of data.It provided a method to identify equipment quickly using the dimension-reduced data.After analyzing the characteristic of the dimension-reduced data,a method using boundary curvature of dimension reduction point set was proposed.In the process,a rolling method based on principle of Alpha Shapes to extract the boundary points was proposed.The curvature of the boundary point was acquired by point-to-chord distance accumulation.Then equipment was idenfified by using boundary curvature.The simulation results showed that the method was concise and efficient.It could identify different equipment and reduce the amount of calculation greatly.
Shen Peihui1,Lin Shuwen2
Abstract: According to the structural characteristics and double-excitation mode of the double-steel-wheel vibratory roller,a seven-degrees-of-freedom jump-vibration model was established fully considered the nonlinear coupling of apparent soil to the compacted system.Taking YZC12 compactor as an example and basing on the decomposition idea of coupling-decoupling-recoupling,the nonlinear vibration response of the system was analyzed in the three representative compaction conditions of smooth contact,slight impact and strong collision.Results showed that,the kinetic offsets between the front and rear wheels were the main reason of the transmission interference.With the change of soil parameters representing different density,the time domain waveform of system became harmonic distortions.The first order,second order and fourth order frequency would generate sub-harmonics and ultra-harmonics until into continuous spectrum of chaos the compaction process.In addition,driving speed mainly affected the vibratory parameters of the front back apparent soils,and then affected the movement interference of the front and rear wheels.Through active controlling the damping system parameters of the frame and the two wheels,the nonlinear vibration responses of the system could be obviously weakened,as well as the transmission interference of the front and rear wheels.
Chen Huaxin, Niu Changchang, Kuang Dongliang, Tian Junzhuang, Yang Kai
Abstract: In this paper,brookfield viscosity test and repeated creep test were adopted to investigate the viscoelastic properties of recycled asphalt and 3 recycled asphalt cements,the viscosity,ΔEη (viscous flow activation energy),Gv (the viscous part of creep stiffness) and cumulative strain γacc of recycled asphalt cements with different fillers were analysised.The experimental results indicated that the recovery levels of viscosity of asphalt and asphalt mastics showed great difference.The regeneration factors in decreasing order were slag asphalt cement > cement asphalt mortar > lime mortar asphalt > asphalt;the viscous flow activation energies of 3 kinds of recycled asphalt cements were increased to varying degrees as well as the corresponding asphalt cements.But the viscous flow activation energy of recycled asphalts were lower than virgin asphalt,the recovery levels of Gv and γacc also showed great differences between the recycled asphalt and recycled asphalt cements.Based on the above indicators,3 kinds of fillers showed different degrees of positive impact on the restoration of viscoelastic properties of aging asphalt mortar,and the order of influences was slag > cement > lime.
Zhang Weidong1,Wang Zhenbo2,He Weizhong1
Abstract: Through the freezing and thawing tests,the influence of replacement rate of rubber on mechanical properties of rubberized self-compacting concrete (RSCC) under different cycle times of freeze-thaw were studied.The results showed that the replacement rate of rubber had great influence on cubic compressive strength and split strength of RSCC under the same freeze-thaw cycle time,but not in proportional relation;cubic compressive strength and split strength of RSCC under the same replacement rate of rubber decreased with the freeze-thaw cycle times increasing.Based on the analysis of the test data,the change law between tensioncompression ratio and freeze-thaw cycle times was given,and the relevant simple formula were regressed between cubic compressive strength,split strength and freeze-thaw cycle times.This study could serve as a reference for durability of RSCC under freezing and thawing environment.
Wu Haipeng, Li Jie, Chen Huai
Abstract: Based on characteristics of the variable cross-section box girder with corrugated steel webs,considering girderheight and bottom plate from the force equilibrium of thickness,the elastic element,the web’ s shear stress formula was derived.It was shown got that shear stress of variable cross-section composite box girder with corrugated steel webs was sheared by top and bottom concrete plate and corrugated steel webs.It was concluded that the variable cross-section composite box girder’ s shear was caused by the section’s shear force,in addition,also including additional shear stress which was produced by bending moment and axial force.Through comparing of the formula solutions section and variable’ s formula and FEA results of constant section,it is indicated that the shear stress calculation formula has higher calculation precision.Finally,based on testing the formula,taking into account three load cases,variable cross-section box girder with corrugated steel webs shear force transfer efficiency was given.
Xuan Tianmei1,Sun Jianwu1,Ge Meiying2,Yin Guilin2,He Dannon1
Abstract: CuO doped zinc carbonate was fabricated by hydrothermal method with zinc nitrate and urea,acetic acid copper and polyvinylpyrrolidone (PVP) as raw material.And the porous zinc oxide was obtained after calcinating.XRD,SEM were used to characterize the structure and morphology of samples.And the effects of CuO-doping on the properties of sulfide hydrogen sensitivity were studied.The results showed that CuO-doped porous zinc oxide for hydrogen sulfide had the better sensitivity,selectivity and stability.It turned out that the device showed the best response at 180 C and the sensitivity could reach 60 to 10 mg/L hydrogen sulfide.It had almost no response to other gases.The porous structure of copper doped zinc oxide could be used in the preparation of sulfide hydrogen sensor.
Zhang Haojia1,Liu Hanhu1,Xiao Xin1,Sun Xiaofei1,Cai Chengzhe2
Abstract: In this paper,the contents of Pb,Cu and Zn in the plants and soil from a coal mine area in northern Xuzhou were examined,to study the enrichment ability of the dominant plants for different hea y metals.24 species (24 genera,12 families) of herbaceous plants in the region were found,including the 8 dominant plants.The results indicated that the average contents of Pb,Cu and Zn in the soil were 1.56,1.10 and 2.70 times to the background values of Xuzhou,and the content of Pb was positively correlated with Cu and Zn (P <0.01).The transfer coefficient of Erigeron annuus was more than 1.00,being 1.01 for Pb,being 1.42 for Cu and being 1.12 for Zn.The content of Zn in Artemisia lavandulaefolia was higher than the normal range,which reached 164.16 mg/kg.even,the plant’ s transfer coefficient and enrichment factor of Zn were 2.08 and 1.13.This two plants had the ability to enrichment the heavy metal,which can be used as a remediation for the ecological restoration of the local coal mine area.
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