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This study explores the curvature and mechanical sensitivity of a pre-stressed layered plate embedded with a piezoelectric layer in large deflection. Piezoelectric effect was included in deriving the nonlinear governing equations but the arising nonlinear terms are neglected, yielding a standard Bessel equation or a modified Bessel equation for the lateral slope. Analytical solutions are developed and further manipulated to obtain lateral curvature and mechanical sensitivity. The results for a nearly monolithic plate under low pretension and low voltage applied across the piezoelectric layer agree well with those of CPT for a single-layered plate under pure mechanical loading. For typical symmetric 3-layered piezoelectric plates, the solutions show that, piezoelectric effect is apparent only up to a moderate initial tension. Beyond a moderate threshold value, the pretension turns to be dominant, resulting in nearly zero curvature and uniform mechanical sensitivity throughout the entire plate.

A 2-covered path routing method providing each path with redundant antennas to provide high availability ensures reliable multi-hop communication under practical conditions. In real life, the transmission range of an antenna increases at a rate proportionate to its input power. This paper focuses on the 2-covered path problem in which antennas have discrete transmission power levels. Given a set of n antennas with m available radii, a source point A and a destination B on the plane, we propose three power-aware methods that construct the 2-covered paths between endpoints A and B. These methods are called 2-covered area stretching planning (TASP), and radii shrinking planning (RSP) to reduce power consumption. RSP and TASP are polynomial-time algorithms and save energy up to 96% of that achieved by optimum solutions.

Combined with the finite element method (FEM) and the field data of Shenyang Metro NTR engineering for pipe jacking process, the variation of surface deformation and influence factors of NTR construction are systematically analyzed. The result is shown that the curves of the lateral surface subsidence produced by pipe jacking process are accord with the normal distribution curves put forward by Peck .When the top steel pipes are jacked , the surface subsidence develops rapidly and the rate of deformation is larger. In addition , grouting behind the wall and the sequence of the pipe jacking all have a greater impact on the deformation of the layer.

In the modern Human-Machine interactive interface, symbol is used to express ideas, and is an important component of information visualization. By analyzing the style of interface design of "skeuomorphism" and "flat" that are two typical symbol designs, we analyze the differences between them, find out the user cases of these two symbols, and explore the future trends of the basic theories about symbol in the contemporary interactive interface. The experimental results show that skeuomorphism is different from flat in terms of five aspects including identity, interest, timeliness, familiarity, and simplicity. At last, we expect our research to provide guidance for the design of interface icons.

Cubic rocksalt (RS) AlN film was grown on MgO (100) substrate by laser molecular beam epitaxy (LMBE) technique, and its bandgap was determined experimentally and theoretically. Based on the analysis of optical transmittance spectrum, the RS AlN film shows an indirect bandgap of 4.807 eV. Using the Cambridge sequential total energy package (CASTEP) module of materials studio (MS) software, an indirect bandgap of RS AlN is predicted as observed experimentally. While the calculated bandgap is smaller than the experimental value, which can be ascribed to the inaccurately handled exchange-correlation energy in the calculations.

The continuity characteristics of spiral space is extremely suitable for function of exhibition buildings. Under the background of rapid development of technology and information, the forms of spiral spaces are becoming more sophisticated and creative. In this paper, we introduce the concept of “topology” and set the latest and most classic cases of spiral space form in Exhibition building, and make a meta-analysis of the idea of spiral space of exhibition buildings in two ways which are geometric topology and natural bionic, and aiming to study the homogeneity feature of the form.

Reasonable color design in medical space can play an auxiliary role in patients’ treatment by researching and analyzing the differences of color psychological needs during patients with different age groups being treated. So this paper proposes a medical space oriented color psychology perception model to present how color design in medical space affects patients’ therapeutic benefits. This model can figuratively reflect the color needs of patients with different age groups and affects patients’ therapeutic benefits by triggering patients’ psychology perception. At last, the experimental results validate the effectiveness of medical space oriented color psychology perception model and present the color need tendency in medical space of patients with different age groups, which plays an important role to improve and perfect health system.

High strength aluminum alloys which improve mechanical properties through heat treatment have been widely used in aviation manufacturing. However, residual stresses that are harmful to the materials are brought in during the heat treatment process. By means of the analysis of micro-indentation method and ANSYS finite element method, the residual stress distribution in 2A02aluminum forgings after water quenching were systematically investigated, mainly considering two factors of the symmetry of structure and the variation of surface constraint. The results of micro-indentation method show that the absolute value of the residual stress within the sample tends to decrease as the condition of constraint increase at the location of the same thickness; the absolute value of the surface residual stress also tends to decrease as the thickness of the sample increase with the same constraint conditions, the absolute value of the residual stress in the symmetrical sample is lower than that in the asymmetrical sample. The results of finite element simulation are as follows: for 2A02 aluminum alloy, the stress field distribution during the process of quenching is mainly influenced by the thickness of the samples. After the quenching process, the stress state at the components surface are controlled by compressive stress in the direction of both thickness and width, while the residual stress within the samples is dominated by tensile stress.

How to effectively control the cost of engineering in-construction is the urgent problem to be solved for highway enterprise. In order to maximize the enterprise profit, cost control measures are discussed in this paper as following aspects, human resources, raw materials and project management. This can be used as reference for highway enterprise.

The speed is the most common frequency signal among a lot of the automotive signal which may be collected, Acquisition for frequency signal generally use the counter input capture. The number of sampling rate not only depends on clock frequency counter, but mainly the number of the frequency of the signal itself, it is bound to take a very long time to collect speed signal when the speed is very low. For most of the data acquisition card, which usually adopt asynchronous acquisition between various channels, that is, only one channel can collect data at any time, so for the multi-signal acquisition system which has a high requirement for real-time, it is undue to collect directly low frequency signal. This paper adopt method of frequency-voltage converter to change the frequency signal to analog signal and collect data, thus, which can greatly improve the system's sampling rate.

This paper reports two films, Ti/a-C and Ti/a-C:H, prepared on the Ti-6Al-4V alloys by magnetron sputtering in PVD and CVD process, respectively. The morphology and microstructure were characterized by Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. Both films show nanosized Ti clusters incorporated into the amorphous carbon matrix. Mechanical properties of the films were investigated by nanoindentation and ball-on-disk tribo-test. Ti/a-C film shows a hardness as high as 40.9 GPa, while that of Ti/a-C:H is 12.2 GPa. Both films show reduced friction and high wear resistance.

Based on the fluid-structure interaction theory, FLAC3D was adopted to conduct a numerical simulation on the excavation of hong shigou hard rock tunnel. The basic mechanical properties for rock mass changed significantly during the process of secondary stress adjustments, and the rock deterioration constitutive model (RDM) can accurately reflect both the abruptness of the rock yield failure and the changes of mechanical parameters after yield. On the basis of RDM, the permeability coefficient with equivalent plastic strain function was introduced which can update the permeability coefficient. The results showed that both the surrounding rock displacement and the volume of plastic zone increased significantly because of the seepage action. Therefore, the seepage of fissure water on the hard rock should be fully considered during excavating and supporting in order to prevent accidents such as water inrush and sudden collapse.

Advanced small pipe support is one of the advanced support patterns in tunnel engineering construction for weak and fractured surrounding rock. The support effect cannot be predicted because of depending on engineering experiences. Efforts are made to study and analyze the support mechanism of advanced small pipe in the excavation of soft - fracture wall rock. By the numerical simulation of FLAC3D of Dawangou tunnel based on rock mass deterioration model (RDM), the plastic zone, displacement and stress filed of the surrounding rock are simulated with and without the advanced small pipe support. The support effect of advanced small ducts in tunnels during excavation by steps is presented.

Based on Ježek method of computing the elastic-plastic buckling of the member under the axial compressive load and the bending moment, considering the initial geometric imperfection, the analytical expressions of calculating the ultimate load of buckling about the neutral axis with the maximum moment of inertia for a square steel tube member with flange outsides wrapped by carbon fibre are derived. Using the elastic-plastic finite element method and the theory of nonlinear buckling, the impact of the initial geometric imperfection on the square steel tube steel member wrapped by carbon fibre under the axial compressive load and the bending moment are analyzed and the numerical solutions of ultimate bearing capacity are obtained. By compared with the values of the finite element method (FEM), it shows that the analytical method in this paper is valid. Compared the reinforced effect of the carbon fibrer to the perfection member with the defect member, we find that the former is higher than the latter. The results of the example also show that the presence of initial geometric imperfection reduces the ultimate bearing capacity of the steel member to a great extent. The influence of defect member gradually decreases when the given moment rises.

Based on Ježek method of computing the elastic-plastic buckling of the member under the axial compressive load and the bending moment, considering the initial imperfection, the analytical expressions of calculating the ultimate load of buckling about the neutral axis with the maximum moment of inertia for a square steel tube member are derived. Using the elastic-plastic finite element method and the theory of nonlinear buckling, the impact by initial geometric imperfections on the square steel tube member under the axial compressive load and the bending moment are analyzed and the numerical solutions of ultimate bearing capacity are obtained. By compared with the values of the finite element method (FEM), it shows that the analytical method in this paper is valid. The results of the example show that the presence of initial imperfections reduces the ultimate bearing capacity of the steel member to a great extent. It is also found that the influence of the initial geometric imperfection on the ultimate bearing capacity of member is smaller when the M increases.

In response to the limitation of conventional index for stability and optimal design of underground rock mass engineering. The new evaluating indicator, local energy release rate, which can analysis the energy release intensity in the process of the brittle failure of hard rock is used in numerical analysis. Numerical simulation of construction sequence was studied for Dawangou tunnel using energy release rate index and a new constitutive model reflecting the brittle failure of hard rock. Based on the change trend of energy release rate, rock displacement and plastic zone, an optimization excavation is suggested. The optimal excavating sequence could serve as reference in the design and construction.

Reasonable evaluation for weak surrounding rock of shallow tunnel under unsymmetrical pressure is very important for the design and construction of tunnel project. The evolvement rule and space distribution characteristic of surrounding rock under different thickness of side covering soil were gained, which include the stress field and plastic zone by adopting rock mass deterioration model, to reveal the instability and failure mechanisms of surrounding rock. And then through analyzing and calculating the measured data in site, the stress characteristics of surrounding rock and supporting structure were gained. The conclusion can be a reference for the design and construction of Hongshigou Tunnel and other similar engineering projects.

The direct mode shape expansion method is an iterative technique, then one can conclude that the convergence performance maybe challenged when applied to three-dimensional structures. In addition, mode shape values at different DOFs (degrees-of-freedom) sometimes are not in a same order of magnitude, which will produce much error for the estimation of small values of unmeasured mode components. Thus, this paper proposed a non-iterative mode shape expansion method based on coordinate decomposition and neglecting modelling errors between the finite element model and the experimental structure. The advantage of coordinate decomposition is that the unmeasured components of mode shape values could be estimated with different weighting coefficients, even in a physical meaningful interval. Numerical studies in this paper are conducted for a 30-DOF (degree-of-freedom) cantilever beam with multiple damaged elements, as the measured modes are synthesized from finite element models. The results show that the approach can estimate unmeasured mode shape values at translational and rotational DOFs in x, y and z directions with different weighting coefficients, respectively; and better mode shape expansion results can be obtained when proper constraints are employed.

An efficient data acquisition system for electronic automatic transmission test, which makes use of American NI’s data acquisition card, is designed based on Virtual Instrument. The data can be collected by the data acquisition system include automatic transmission oil pressure, solenoid duty, as well as engine speed ，turbine speed ，output shaft speed and throttle degree，and so on. The key problems of the system design are measurement method of automatic transmission solenoid duty, signal conditioning circuit design and multi-signal acquisition synchronization. Test platform is North-Benz dump truck 2627K (Its power-train assembly is replaced), of which transmission and engine use respectively HD4070PR electronic automatic transmission and BF6M1015CP electronic diesel engine. The automatic transmission shift control strategy and oil pressure characteristics of clutch or brake etc can be analyzed through test data acquisition.

It is the key to success or failure of the construction that we control the ground surface settlement, vault sink and supporting force by the choice of the reasonable construction method in the subway construction process. Based on the project profiles of the tunnel in Nanjing orbit traffic line 1 from South Yan'an road to NingDan road, the article mainly carries on the numerical simulation to construction program by using ANSYS finite element software according to the joint arch tunnel construction of the double and triple arch in the entry end .The article mainly has an analysis from the ground surface settlement, the strata, axial force of supporting structure, bending moment and other aspects. The results show that the program is feasible. The article provids guidance to the future construction of similar projects .

A data acquisition system for electronic automatic transmission test, which makes use of American NI’s data acquisition card, is designed based on Virtual Instrument. The data can be collected by the data acquisition system include automatic transmission oil pressure, solenoid duty, as well as speed of turbine and output shaft of transmission and throttle degree of engine and so on. The key problems of the system design are measurement method of automatic transmission solenoid duty, signal conditioning circuit design and how to improve sampling rate of the system. Test platform is of a armored vehicle which has equipped a high-power electronic automatic transmission. The automatic transmission shift control strategy and characteristics of throttle oil pressure etc can be obtained through test data acquisition.

Based on Ježek method of computing the elastic-plastic buckling of the member under the axial compressive load and the bending moment, considering the initial imperfection, the analytical expressions of calculating the ultimate load of buckling about the neutral axis with the maximum moment of inertia for an H-shaped member are derived. Using the elastic-plastic finite element method and the theory of nonlinear buckling, the impact by initial geometric imperfections on the H-shaped steel member under the axial compressive load and the bending moment are analyzed and the numerical solutions of ultimate bearing capacity are obtained. By compared with the values of the finite element method (FEM), it shows that the analytical method in this paper is valid. The results of the example show that the presence of initial imperfections reduces the ultimate bearing capacity of the steel member to a great extent. It is also found that the influence of the initial geometric imperfection on the ultimate bearing capacity of member is smaller when the bending moment increases.

This study simulates the slope stability at Jiu-Fen, using the limit equilibrium method and the finite element method. The limit equilibrium method can find potential slide surfaces and safety factors rapidly. The advantage of the finite element method is that it utilizes more reasonable soil behavior and boundary conditions. A critical slide surface obtained by the limit equilibrium method can be compared with the displacement vector, stress field and location of plastic zone obtained by the finite element method. Furthermore, we can compare the safety factors produced by the two methods. This study shows that the safety factor from the limit equilibrium method is higher than that from the finite element method. The displacement analysis by the finite element method agrees well with the progressive slope failure. So, if we combine the two methods using monitored data in the field, we can analyze slope stability clearly.

Based on Ježek method of computing the elastic-plastic buckling of the member under the axial compressive load and the bending moment, considering the initial geometric imperfection, the analytical expressions of calculating the ultimate load of buckling about the neutral axis with the maximum moment of inertia for an H-shaped member with flange outsides wrapped by carbon fibre are derived. Using the elastic-plastic finite element method and the theory of nonlinear buckling, the impact of the initial geometric imperfection on the H-shaped steel member wrapped by carbon fibre under the axial compressive load and the bending moment are analyzed and the numerical solutions of ultimate bearing capacity are obtained. By compared with the values of the finite element method (FEM), it shows that the analytical method in this paper is valid. Compared the reinforced effect of the carbon fibrer to the perfection member with the defect member, we find that the former is higher than the latter. The results of the example also show that the presence of initial geometric imperfection reduces the ultimate bearing capacity of the steel member to a great extent. The influence of defect member gradually decreases when the given moment rises.

Model which depends on historical data of Jiangxi Province ，grey system and Brown nonlinearity exponential smoothing has been constructed, then the paper uses of MATLAB software integration to calculate parameters, precision testing and result graphical output process to program the forecasting model .By establishing the future energy combination forecasting model of Jiangxi province with the standard deviation method, it can predict the energy gap of Jiangxi Province in following 12 year. The result shows that the whole energy gap will reach 561.206 million tons tce in 2009-2020.

After making deep analysis of the geospatial data organization mode, data clipping, data extraction, data mosaic of terrain original data, which are based on geospatial database theories such as ArcGis, GeoDataBase, are studied in detail. This research, beneficial for sharing and inter-operation of spatial information, makes it possible the realization of the three-dimensional visualization in Yuntai Mountain area of Jiaozuo.

Considering the requirements for efficiency and precision in the forklift styling, the authors developed the forklift optimizing system for its styling based on the interactive genetic algorithms (IGA). The system includes parameter optimization, color optimization and part combination three modules. The parameter optimization module can find the user defined parameters of the forklift 3D models and generate new models. Color optimization module can group the model surfaces and render the groups with different color. New color plans are generated through random changing of the colors in each group. The parts combination module divides forklift into several parts and build lib for each part. The module can pick parts from the lib and assemble them into a whole forklift and demonstrate them. The thesis developed a protosystem on the Solidworks platform with VBA programming tools. Interactive genetic algorithms are applied to realize the three module’s function.

The nonlinear problem of large deflection of an elastically-bossed layered plate under pretension due to lateral load is studied. The approach follows von Karman plate theory for large deflection for a symmetrically layered isotropic case. The thus derived nonlinear governing equations are solved using a numerical finite difference method with the aid of an iteration scheme. For a nearly monolithic plate with a thin boss, the obtained solutions correlate well with those available in literature for a single-layered flat plate, thus validates the presented approach. For three layered symmetric plates made of typical silicon based materials, various initial tension and lateral pressure are implemented. The results indicate that, edge behavior may appear at both the boss edge and the clamped end of the plate, thereby revealing severe variations for the structural responses. Varying the central boss size and relative thickness may have a sensible influence upon the behavior of the bossed layered plate. Furthermore, lateral pressure appears to have a sensible effect upon the nonlinear behavior of the bossed layered plate. For a relatively large initial tension, however, the pretension effect dominates, yielding a total membrane behavior for the bossed plate, regardless of the size of the center boss, except in the vicinity of the clamped edge.

The transportation network dynamic port and the correlation question are in the intelligence transportation system the transportation flow the induction the core theory. This article has first studied the immediate road section transportation time dynamic user most superior assignment characteristic and the road section equation of state, and has established the immediate road section transportation time dynamic user most superior assignment model. In the third part, mainly discussed but should grasp for the time discrimination and the Frank-Wolfe algorithm which the solution immediate dynamic user route selection model; the article finally uses the example through the test, to the model which establishes has carried on the simulation.

The non-fragile guaranteed cost control is discussed for the polytopically uncertain switched discrete time systems with multi-delays in states and inputs. Based on the piecewise quadratic Lyapunov functions, the synthesis approach of the delay-dependent non-fragile guaranteed cost controllers is proposed. By the obtained control law, the perturbed switched discrete time systems can be asymptotically stabilized and the close loop cost is not greater than a specified upper limit for all admissible uncertainties. The numerical example is given to illustrate the validity of the presented controller design method.

This paper takes a certain solid rocket engine as the research object, and studies the optimal measuring techniques of static trust line based on coordinate conversion. A simulation was taken to measure the thrust line of a rocket motor which has concave arc-paraboloid structure. The experiment proved that the technique proposed in this paper provided higher measuring efficiency and better accuracy.

End-hopping is a technique proposed in the study of active defense in network security. In this paper, core technology analysis is made to the conception of “End-hopping” based on the previous research of our group. And the formal description is put forward. Methods are discussed and comparative analysis is made to implement End-hopping for active defense.

The non-fragile robust H∞ control problem is investigated for the uncertain switched discrete time systems with multiple state and input time delays. As the system and controller parameters are polytopically uncertain, the delay-dependent sufficient conditions for the existence of the non-fragile robust H∞ controller via state feedback are presented for the systems based on the multiple Lyapunov functions and state dependent switching rules. By using the cone complementarity linearization algorithm, the nonlinear matrix inequalities relevant to the controller design can be transformed into the nonlinear programming problems constrained by the linear matrices. The simulation results show the effectiveness of the controller design method.

The power generation characteristics of electroactive acrylic elastomer (EAE) were studied by experiments based on theoretical analysis. The generator mode theory fundamentals of EAE were discussed and studied. A power conversion control system for EAE was designed. The experimental results show that energy generated as nearly incompressible elastomer layers increase in area and decrease in thickness when EAE stretched, and power generated when EAE relaxed. The voltage of generation increased with the bias voltage increasing. The experimental results accorded with analytical model and lay the foundation for generator of EAE.