Abstract:还未完成，以后补齐

Abstract:The paper presents a theoretical study of the temporal features of deformation and fracture of rock and rock mass and an investigation of the strain rate dependence of strength and its mechanism.The paper also presents the Mohr-Coulomb constitutive relations with a consideration of strain rate dependence and the relationship between the size of blocks of fractured rock mass and the strain rate.Several temporal fracture criteria are discussed,and their intrinsic relationship is revealed.Finally,the application of dynamic strength theories is discussed.

Abstract:通过高含盐水泥土室内无侧限抗压强度试验,研究了Mg2 ,Cl-,SO42-离子含量变化对高含盐水泥土强度的影响及其变化规律;利用X射线衍射和扫描电子显微技术,分析了不同离子含量下水泥土的微观结构特征及其与水泥土强度的内在联系.研究结果表明,水泥土强度与C—S—H及C—A—H总含量存在很好的线性相关性;高含盐软土中Mg2 ,Cl-,SO42-含量变化不仅引起水泥土微观结构的差异,而且高含量对水泥土强度有不同程度的负面影响,这应引起工程应用中的重视.

Abstract:Cyclic loading tests on structural members are carried out on different boundary conditions.The equivalence of the boundary condition is discussed by analyzing the results of 5 steel reinforced concrete(SRC) columns subject to cyclic loadings,which are respectively fixed at two ends or pin-restrained at two ends.A comparative study is made on the skeleton curves,key points and characteristics of hysteretic curves of specimens on different boundary conditions .Based on the numerical analysis of the mechanical model,the phenomena of test results are explained.The study shows that boundary condition has no evident effect on the ultimates and deformation capacity,however nonideal boundary restraint has certain influence on the initial stiffness,shape of the skeleton curve and energy dissipation capacity.

Abstract:The effectiveness of storm rope for long suspension bridge's flutter control is investigated by comparing different tension forces and anchoring positions.With finite element method(FEM) and Rayleigh method,the varied tendency of frequencies is examined,which is followed up by a full-scale aeroelastic model test in wind tunnel TJ-3 in Tongji University.The study shows a notable increase of natural frequencies of bridge just by applying storm ropes to the mid-span.However,special attention should be paid to the storm rope's anchoring position at the main cable,which would induce more instability of the structure during some certain periods of construction.Because of the complexity of this issue,it is strongly recommended that wind tunnel testing be conducted before the application of storm ropes.

Abstract:14 global positioning system(GPS) receivers were employed to monitor the deformations of the Nanpu Bridge in Shanghai for 4 consecutive days in September 2006.A dedicated bridge coordinate system was established to analyze and relevant algorithm was used for the coordinate transformation.The precision of the resulting coordinate time series and the static and dynamic characteristics of the bridge deformation were analyzed.Analysis results show that GPS positioning is fully capable to monitor the deformations of medium to large size bridges and the critical parameters about the structural health conditions of these bridges can be reliably extracted from the 3D coordinate time series.Through the trial,it further proves that GPS positioning technique has unique merits over other traditional monitoring tools.

Abstract:Methods of aircraft repeat load analyses are discussed in this paper, which are used in mechanistic-empirical pavement design procedure.According to the general pavement design concept advanced by Monismith,the load repetition calculating methods for fatigue and rut analysis are put forward based on a study of the spatial pavement responses.For fatigue analyses,the specific formulas of single axle about stress and strain repetition are put forward,along with the load repetition calculating methods under the impact of mutiple axles.Based on a study of A380's complex gear,the calculating methods for the new generation large aircraft are proposed.The load repetition calculating methods of flexible pavement for rut analyses are similar to that for fatigue analysis.For the semi-rigid asphalt pavement,its load repetition calculating methods can be established according to the maximum trace trip and total loading time.

Abstract:This paper presents an introduction to the approach to the calculation of fractal dimension of grain size distribution and also an analysis of the fractal characteristics of asphalt mixture aggregate.The fractal of dense-graded aggregate is one-dimensional,but the fractal of gap-graded aggregate is two-dimensional.Dc(fractal dimension of coarse aggregate) and Df(dimension of fine aggregate) are used as the indexes to describe the fractal characteristics of asphalt mixture aggregate.Additionally,the fractal gradation theory is put forward,not only used for the design of dense-graded aggregate,but also for gap-graded aggregate.An analysis is made of the relationship between the fractal gradation theory and other gradation theories.The results show that the fractal gradation theory covers the existing gradation methods.The cause lies in the fact that fractal is the essence of aggregate.

Abstract:A series of tests,such as fatigue test,reflective cracking modeling test and impact ductility test,are jconducted to compare the ability of high elasticity asphalt,AH-70 asphalt and AH50 asphalt to resist reflective cracking.Tests results show that the fatigue life of high elasticity asphalt hot mix asphalt(HMA) is 88 times as long as that of AH-70 asphalt and 55 times al long as that of the AH-50 asphalt.The corresponding load cycle of initial cracking of high elasticity asphalt HMA is 2 times lager than AH-70 and AH-50 asphalt HMA.High elasticity asphalt HMA is about 2 times stronger than AH-70 and AH50 asphalt HMA in the impact ductility.As a result,high elasticity asphalt is more resistant than the other two materials to resist the reflective cracking.

Abstract:Since operation mechanism of traffic flow has not been given enough emphasis to the management and control strategy of on ramp is short of pertinence and maneuverability.Models were built on the basis of the kinematic wave theory to study the operation station and evolvement rule of traffic flow in the join area of expressway and on ramp together with traffic flow of upstream,downstream and ramp under different flow rate.The formation and transmission rule of traffic jam in the join area without any control strategy are also studied.Analysis with actual traffic data shows that the operation mechanism proposed in this paper agrees well with the actual traffic operation in the join area.

Abstract:A quantitative analysis is made of street networks of Beijing,Shanghai,Tokyo,Osaka,Washington,D.C.and New York City.The structures of town block were reviewed and the relationship between the street/town block and the address indication were revealed as well.The results show that the average area of town block in Chinese cities is the largest;the town block is composed as a whole structure in Chinese city,while the buildings are located separately in the town block of Japanese city;the street system of address indication is mainly applied in Chinese cities,while the block system is applied in Japanese cities.

Abstract:采用模拟试验的方法,考察混凝剂与粉末活性炭(PAC)投加去除姚江原水溶解性有机物(DOC)的效果.试验结果表明,表征活性炭吸附性能的碘值与亚甲基兰值与有机物去除效果无显著相关性;混凝处理主要去除的是分子质量1×104~3×104u区段的有机物,而粉末活性炭处理其他区段的有机物效果较好,尤其是分子质量小于1×104u区段,去除率均在40%以上;混凝处理分子质量小于3×103u区段的有机物效果较差,几乎全部依赖粉末活性炭去除,该区段质量分数占姚江原水的70%,这是处理姚江原水时粉末活性炭投加量相对较大的主要原

Abstract:研究了酸化浓度、温度与时间等条件对海泡石在恒温密闭空间内调湿性能的影响.利用X射线衍射仪、扫描电子显微镜和比表面积仪等测试了处理前后的海泡石的微观结构并分析了其与调湿性能的关系.结果表明,酸化条件对海泡石在密闭空间内的调湿性能有明显的影响,酸化处理后的海泡石纤维变细变短,层间和孔道中的碳酸盐被溶解,孔道被疏通.试验获得的最佳酸化条件为用1.2 mol.L-1的盐酸在95℃下处理6 h.经最佳酸化处理后,海泡石的5~10 nm的微孔体积增大,累积孔容积增大,比表面积略有下降.

Abstract:Based on Landsat ETM and SPOT image taken in 2002,other chart or text information and field investigation,spatial attribute database for landscape evaluation indices in the Three Gorges of the Yangtze River(Chongqing Areas) of China is established with geographical information system(GIS) technique.The evaluation model of the landscape visual sensitivity of the valley is defined on the basis of fuzzy mathematics theory,the degrees of membership of each single index are obtained using map algebra of GIS,and fuzzy relationship matrix is set up for each grid as well.The weight value distribution set of evaluation indices is established by means of Delphi investigation procedure.In order to get a combined index representing the degree of membership of the various factors for each grid,weight-operation is conducted on each index of the specific sensitive level with GIS grid calculator,and then the landscape visual sensitivity is determined for each grid following the maximum principle.The results show that landscape visual sensitivity can be classified into four levels in Three Gorges of the Yangtze River(Chongqing Areas),of which the first-sensitivity-level(the highest sensitive) area accounts for 2.38% in the region;the landscape visual sensitivity is strongly related to the horizontal distance form a viewer;and generally,the well-known landscapes have higher landscape visual sensitivity.Finally,this paper presents some strategies and measures for landscape protection,conservation management,and planning and design.

Abstract:A tire-suspension-body mathematical model is established based on the twist-beam suspension with time delay being considered.Polygonal wear of tire based on self-excitation theory is discussed.The results show that the polygonal wear is a typical nonlinear self-excited vibration and the frequency range of self-excited vibration fluctuates according to vehicle types and the status of tire worn.The common range of the frequency is from 100 Hz to 400 Hz;polygonal wear of tire(self-excited vibration) occurs when the velocity of a car reaches a given range;the polygonal number of the polygonal wear of tire is equivalent to the ratio of the natural frequency of the system of the selfexcited vibration to the rotational frequency of tire;within the given range,the natural frequencies of tire have a great effect on the system of the self-excited vibration;the twist-beam suspension has little effect on tire polygonal wear.

Abstract:A theoretical thermo-mechanical coupling dynamical model was established,which consists of road irregularity excitation model,two-degree-of-freedom suspension vibration model,empirical shock absorber damping force model by taking temperature effect into consideration and shock absorber thermodynamic model.The empirical shock absorber damping force model was formed as a nonlinear look-up-table by using the damping force,relative velocity and temperature measured under various sine and stochastic displacement excitation.And the parameters of the shock absorber thermodynamic model were identified based on the shock absorber thermodynamic characteristics test.Using the thermo-mechanical coupling dynamics model,shock absorber's operational temperature was predicted and the influence of factors was also numerically investigated.Results show that the thermo-mechanical coupling effect of shock absorber is obvious when vehicle runs on low-grade pavement with high speed.And the simulation results show that vehicle speed,pavement grade,ambient temperature and air flow rate around shock absorber,unsprung mass,shock absorber tube radiating area have great effect on equilibrium temperature,while sprung mass,suspension stiffness and shock absorber thermal capacity coefficient have little effect on equilibrium temperature.

Abstract:Based on the self-designed 100 kW fuel cell test bench,a test is carried out on the polarization curve,current density and single cell consistency of two types of proton exchange membrane fuel cell(PEMFC).A method to evaluate the single cell consistency is put forward.The test results show that there is a great difference between these two PEMFCs in their performances.When applied to automobile,the PEMFC has a better adaptability to the environment under higher pressure operation.

Abstract:The paper first presents a new space vector pulse width modulation method(SVPWM),and then the deduction,verification and simulation based on the software of Matlab.The novel SVPWM and the classical SVPWM were implemented in the digital signal processor(DSP) of TMS320LF2407,and the execution time of two programs were compared.Simulation and experiment results show that the new method features easy computation and higher utilization of the DC-link voltage,and optimizable switching frequency,so it promises wide application in future.

Abstract:The recent research progress of Petri-net-based modeling for semiconductor wafer fabrication is presented,including the important characteristics of semiconductor wafer fabrication,modeling approach,modes of Petri-net,scheduling methods and real application.Finally,the paper presents some problems worthy of further study and probably developing trends in the semiconductor manufacturing field.

Abstract:The main problem with the text clustering algorithm based on vector space model(VSM) is that semantic information between words and the link between the various dimensions are overlooked,resulting in inaccuracy in the text similarity calculation.A method based on computing the text similarity using semantic distance and two-phrase clustering is proposed to improve the text clustering algorithm.First,the text analyzed according to its semantic,with nearest neighbor algorithm used for the first cluster.Some feature words are chosen according to the similarity weight to represent the cluster with the remaining feature words similar to the main themes of the cluster,and then class combination is carried out.Finally,the second clustering is carried out to improve the nearest neighbor clustering which is sensitive to the input order of the document.Simulation experiments indicate that the proposed algorithm can solve these problems and performs better than the text clustering algorithm based on VSM in the clustering precision and recall rate.

Abstract:The paper presents a new filter algorithm based on the sequential systems of linear equations,and infeasible QP-free method.The new algorithm just needs to solve two systems of linear equations with the same nosingular coefficient matrix and avoids large computational amount and infeasiblility of quadratic subproblems,which are the defects of the existing sequential quadratic programming type algorithms.The X-active set procedure is used to improve the computational effect,and the global convergence of the proposed algorithm is given.Finally,the paper presents the numerical results to validate the efficiency of this new algorithm.

Abstract:Two stochastic seismic-geological models and one stochastic model for well Zh1 are set up based on the type and characteristics of dolomite Peleokarst reservoir(depth>5 000 m) in Tazhong area,China.Using high-order finite difference method of first-order elastic wave equation,the seismic forward modeling is carried out to determine the seismic response.The results show seismic response is characterized by peakvalley-peak which is like strings of beads when thickness of peleokarst reservoir is not less than 7 m and the wavelet frequency changes from 20 to 30 Hz.The reflection amplitude and strength increases obviously if the filled materials become softer and even become the fluid content or the wavelet frequency increases.It also reveals that seismic resolving power for a single layer of peleokarst reservoir is better than that with a stack of peleokarst reservoir beddings of the same net thickness.

Abstract:Laser frequency stabilization derived from Cr atomic beam laser induced fluorescence is a good way to solve excursion of laser frequency in Cr atom lithography.Calculation and experiments are conducted to reveal the effects of laser power and crucible temperature on the induced fluorescence intensity .With fixed crucible temperature,the central intensity of fluorescence doesn't change very much after the laser power reaches 6mW due to the Cr saturation absorption.In addition,the higher power the laser has,the larger full width at half maximum(FWHM),and the lower contrast the fluorescence will have.With fixed laser power,the higher temperature the crucible is at,the higher central intensity fluorescence will have due to the fact that the higher temperature of crucible can make more atoms,and the sharper contrast it will have,but the FWHM doesn't change much with crucible temperature.The experiment result agrees with calculation well.

Abstract:An improved model based on acoustical radiosity was proposed to investigate sound decays in a system of two coupled spaces.The coupling aperture was assumed to be two virtual surfaces and the acoustical radiosity on these surfaces was employed to implement sound energy exchange between two subspaces.Therefore,the computation of acoustical radiosity can be individually conducted in each subspace,and the computational expense is reduced significantly.Moreover,the improved model avoids errors due to visibility checking for elements on different subspace boundaries.Comparisons with field measurements show that the improved acoustical radiosity model can predict sound decays accurately in coupled spaces and has satisfactory convergence.