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This paper focuses on developing a novel control strategy of synchronizer for dual clutch transmission. The synchronization process is investigated and a mathematical model of synchronizer is proposed. The paper proposes a switch control method for synchronizer which is a hybrid dynamical system. The simulation results demonstrate that the performance of the switch controller is reasonable and effective.

Hood is an important part of the automobile, which directly affects the vehicle performance. This paper takes the hood as an example, first of all the three-dimensional model in CATIA was imported into Hypermesh, then it was simplified and meshed, the constrained mode and the stiffness of several conditions were calculated by Optistruct. By using the Size Optimization based on sensitivity analysis, the minimum hood mass is defined as the objective function; each component’s thickness was optimized under the prerequisite of ensuing stiffness and the first modal of hood. The results show that: the optimized hood meets stiffness requirements, the whole vehicle performance can be improved, therefore, the lightweight design in this paper is effective.

In accordance to the drawback of amphibious vehicle's low speed in water, a new kind of folding mechanism based on double wishbone suspension is proposed. Referring to the working conditions of the wheel lifted mechanism, the hydraulic circuit, which provides with the functions of pressure limiting, locked and pressure retaining, is designed to ensure the accuracy of wheel lifted and the driving safety. The appropriate hydraulic cylinders, hydraulic components and auxiliary components are chosen due to the hydraulic system load and the maximum flow rate.

In combustion of a circulating fluidized bed, primary air plays a key role in keeping materials fluidized and regulating bed temperature. This report provides a design of reference governor for primary air fans to amend their control commands. That will improve the combustion efficiency via regulating primary air flow rate timely according to the changes of coal feed flow rate and bed temperature. To deal with the large inertia and slow response feature of primary air fans, a rule-based control method was used to design the reference governor. Based on the experiences of technical experts and operation data analysis, an expert rules system with wide coverage range was developed, which composed of the logical relationships between the coal feed flow rate, bed temperature and the primary air flow rate in various operation conditions. Test results show that designed reference governor can improve the control performance of primary air flow rate obviously.

One of the major challenges in constructing wireless sensor networks (WSNs) is to ensure the quality of coverage (QoC) as well as save energy. Considering the cooperative sensing model and the random deployment policy, the judgment model of redundant node without location information is presented. Furthermore, the distributed collaborative scheduling algorithm (DCSA) is designed to guarantee the QoC of networks with the least number of nodes. It chooses the uniformly-located working nodes and makes sure that the energy consumption of each node consumes homogeneously. Simulation results show that the DCSA policy not only provides the desired QoC of networks, but also reduces the number of working nodes significantly, saves the energy of the networks, and extends the network lifetime.

In order to resolve the modelling problem of business processes collaboration, especially, the asynchronous communication mechanism problem and the verification problem, combining the respective strengths of Petri Nets and the classical process algebra CCS, a modeling method is proposed in this paper. First of all, modelling the internal view of cross-organization based on Petri Nets, extracting the communication interface and mapping to internal transition to get the public view; Secondly, researching on the asynchronous communication mechanism and modelling the communication process by CCS to get communication behavior view, thus making the verification of collaboration converts to the CCS derivation; Finally, an algorithm is proposed to generate automatically the behaviors possessed by every transition in model view. The modelling method proposed is not only to analyze and verify the structure properties in collaboration, but also to analyze and verify the behavior properties, which brings a huge convenience for further analysis and verification in cross-organizational business process collaboration.

Nowadays, fuzzing is one of the most effective ways to identify software security vulnerabilities, especially when we want to discover vulnerabilities about documents. According to the principles and ideas of Fuzzing, a vulnerability discovery system named WFuzzer is developed. This system can overcome the disadvantage of old ways; it also effectively improves the detection of potential unknown security vulnerabilities. This system is more automated and performs better in finding new security vulnerabilities.

The quantitative classification of transformer supervision can improve the quality of transformer supervision. For the contents of transformer supervision, this paper establishes an index system of transformer supervision. Example results show that the extension matter-element theory which is applied to transformer supervision quantitative evaluation is more reasonable. According to the categories of transformer supervision, this paper quantifies the uncertainty and builds the evaluation system of transformer supervision. It realizes the evaluation of transformer supervision and gets the key factors which influence the transformer supervision. This evaluation system is conducive to guide the transformer supervision to be more scientific and effective.

In the mechanical processing, fixture has an irreplaceable role, but in the traditional design methods, there are many shortcomings, the rapid prototyping technology is used in the design of fixture was mainly introduced. The defects of fixture design was introduced at this stage, the rationality of rapid prototyping technology used in fixture design was analyzed, then, the advantages of rapid prototyping technology used for fixture design was highlighted, through the concrete example and the forming process of display.

The acquisition of information about channel coding sequences is the research emphasis and difficulties at present, and recognizing the channel coding parameters is the prerequisite for information acquisition. RS Codes are a class of linear block codes as well as a special class of BCH Codes and cyclic codes. It regards a group of symbols with a length of n as a unit to process with, and the n symbols are generated by k transmitting information symbols under some proper associated rules. RS Codes are widely used in various communication systems. In this paper, an algorithm of RS Codes blind recognition is researched. And a blind recognition model is established on MATLAB. At last, the paper presents the recognition rates of situations with different error rates.

Amount of legacy systems in early stages are fall behind multi-core ages, and these legacy systems were designed for single processor which can not expand the computing power of the multi-core hardware. In this paper, we employ aspect oriented programming technology and design the crosscutting concerns for the potentially parallelizable software components of legacy systems. We propose a new multi-core programming model which can change the single thread of legacy systems into multi-threads for multi-core hardware platform without revising the source code of legacy systems. The proposed method can enhance the performance of software and utilization of hardware.

A theoretical model is developed for the analysis of piston secondary motion. Based on this model, the slap force of a specific L6 diesel engine was compared when considering different boundary conditions, such as lubricating oil on cylinder liner, surface roughness, deformation of cylinder liner and piston skirt. It is concluded that it is necessary to consider the secondary motion of piston in the analysis of the inner excitation for an internal combustion engine. A more comprehensive consideration of the boundary condition (i.e., more close to the actual condition) will lead to a smaller maximum slap force, and among all boundary conditions considered in this paper, the structural deformation of the piston skirt and cylinder liner is the most influential factor. The theoretical model developed and findings obtained in this study will benefit the future analysis and design of advanced internal combustion engine structures.

The mathematical model based on graph theory and the refrigerant natural cycle system of gas-liquid two-phase flow network is established. Incidence matrix was used to describe the relationships between the various components. The node conservation equations, branch equations, momentum conservation equation in return circuit and mass conservation equations of system are established. The model was solved by using variable step gird iterative method. Then refrigerant state of each node and refrigerant flow of each branch in network model are obtained. Establishment and solution of the RNC network model provides an effective way for the further performance analysis of system.

In order to improve the personification of human-robot emotion interaction, this paper based on the Euclidean space emotion model and Ekman theory of emotion, deduces the general formula of emotion characteristic value, establishes a improvement model of robot which can express the robots emotion through the body language. The general formula of emotional feature value make the models suitable for the expression of various emotions, and through body language to express the emotions, improves the emotion expression model generality and adaptability.

Based on the transformation project of rain and sewage diversion in a city, the optimized design of Larsen steel sheet pile supporting structure in pipe-pit excavation was made. Using three-dimensional finite element method to analyze the retaining characteristics of Larsen steel sheet pile, soil deformation of adjacent transverse brace in the middle position and surface subsidence were regarded as design control indicators; through numerical analysis of the geological conditions, load, pile length, horizontal interval of transverse brace and other factors on the sensitivity of the design control indicators, horizontal displacement of brace was regarded as a key factor in the optimal design, and accordingly, related optimized program was proposed. The implementation results show that the optimized scheme can improve the efficiency of construction, protect the safety of construction, and provide a reference for the design and construction of similar projects.

To tackle the problems brought by the wired terminal multiplying and complexity of the wireless terminal cluster, the thesis designed handheld terminal design based on the wireless sensor Internet for contestants. It solves problems such as complex cluster and bad communication performance of the terminals in traditional contests with the help of zigbee technology. Besides the common function, it possesses extra functions, such as voice prompting, judge scoring and audience voting. The thesis mainly deals with the hardware and software design. The test result shows such design can better meet the needs of sorts of contests with the advantages of automatic networking, multiple function and stable performance, etc.

This paper proposes a face recognition algorithm based on the combination of local binary pattern (LBP) texture features and extreme learning machine (ELM). The face image is divided into several regions, and the LBP features are extracted from these regions and combined together to form a feature vector which will be the input data of ELM. It shows that ELM performs well in classification applications, and ELM and support vector machine (SVM) are equivalent from the optimization point of view. But ELM has milder optimization constraints and much less training time. Our experiments are carried out on two well-known face databases, and the results show that compared with compared to PCA+NN, PCA+SVM and PCA+ELM the proposed method can achieve higher recognition rates.

The problem of robustly non-fragile guaranteed cost control for a class of uncertain time-delay switched singular systems under arbitrary switching laws is considered. By means of matrix equivalent transformation and the relationship between the norm and the matrix, based on linear matrix inequality tools, a sufficient condition on the existence of non-fragile guaranteed cost state feedback controllers is derived, which ensures that uncertain time-delay switched singular system is admissible, and a corresponding cost index can be guaranteed. The design problem of the non-fragile guaranteed cost controller can be turned into the feasibility problem of a set of linear matrix inequalities. Finally, an illustrative example is given to demonstrate the effectiveness of proposed method.

Because of speediness urbanization, the numerous greenhouse gas is being let because of human activity. The impact of the associated factors on the metropolitan area is the hot research area. This paper focuses on the numerical simulation of weihais meteorological parameters, including atmosphere temperature and rainfall, trying to find establish a method to research the relationship between the urbanization and the climate change.

The problem of robustly asymptotic stability and controller design for a class of switched uncertain singular systems with time-delay is considered. By means of Lyapunov function and Matrix equivalent transformation, based on multiple Lyapunov function techniques, a delay-dependent sufficient condition is deduced, such that the solution of the switched singular system with time-delay is robustly asymptotic stable for all admissible uncertainties under an appropriate switching law. Furthermore, a convex optimization problem with LMI constraints is formulated such that the maximum bound on the admissible delay can be determined by using the LMI toolbox in MATLAB. Finally, an illustrative example is given to demonstrate the effectiveness of proposed method.

A designed scheme of Vehicle navigation terminal interface Based on QT is presented. According to the current high cost of vehicle navigation terminal is common problem. The paper focuses on the design process of the Linux OSQT GUI and electronic map. The establishment of the communication way of GPRS and the analysis of the GPS data is finished in this paper. The design options of software, combining with hardware, is effective to solve real-time and dynamic update problem of electronic map display, data update, path query functions , The design of the Vehicle navigation terminal provides an important prerequisite for realizing the urban traffic vehicle global optimization and dynamic navigation.

The working condition of the condenser in power plant is an important factor that affects the economic operation of the power plant. Rubber ball cleaning is a main method to deal with the condenser fouling. The thesis, dealing with the problem of counting errors of rubber ball in the process of condenser cleaning, based on CPLD(Complex Programmable Logic Device) technology, designs a programme have rubber balls checking and counting automatically. The program takes use of the controlled laser sensors to count the number of rubber balls in every single pipe and the parallel processing capacity of CPLD,and have the number of different pipes counted and shown. Experiments have proved its constancy and accuracy.

“Internet of things” (IOT) is a very new concept created and developed in recent years. It had not been paid front attention until one or two years ago, when Chinese and US leaders announced emphasis on the development of IOT. To recover global economy under the economic and monetary crisis background, innovative technologies such as IOT are critical to create new economic development growth points. This paper first introduces the concept and origin of IOT, then describes basic principles of IOT, next illustrates the framework of IOT, and finally takes two examples to suggest applications of IOT. The paper intends to help readers recognize IOT as a whole, to hold the clue and venation of the development of IOT, and to forecast future trends of IOT development.

The purpose and meaning of bridge health monitoring is sketched in this paper. In order to study of the structure of the bridge health monitoring problems, First of all, a finite element model for simply supported steel beam is set up on the basis of the Finite Element Theory and the software ANSYS in response to laboratory of the finite Element Theory and the software ANSYS in response to laboratory experient. Identify the different injury by comparing the index value and the rate of change. Through adding instantaneous excitation to the mid-span, do Harmony Response analysis for different injury of steel bridge model to reveal the frequency amplitude diagrams, from these diagrams can be found on the "peak" response. We can identify the different injury by comparing the index value and the rate of change.

Based on the input-output theory, the paper using the comparable price energy input-output table,quantitatively estimates the implicit carbon emissions of each industrial department,and analyzes the growth of the implicit carbon emissions of the resident consumption through the structure decomposition.Conclusion indicates:From 1992 to 1997, the mean of the implicit carbon emissions of each industrial department in Xinjiang had been rising; From 1997 to 2007, the mean of the implicit carbon emissions of each industrial department had been declining;The implicit carbon emissions of Hydropower industry, the fire power and other seven similar industrial department were higher than that of each industrial department so that Xinjiang should strengthen monitoring on the high energy consumption.The implicit carbon emissions of the resident consumption was still in the trend of ceaseless growth and all of that states clearly that the economic grows at the cost of the increase of the greenhouse gas emissions.Xinjiang should introduce foreign advanced production technology,further optimizing the structure of the resident consumption.

In this paper, we have investigated the impulsive controller of suspension system of single magnet. The variable system parameters are formulated through matrix analysis. The sufficient conditions of the robust asymptotical stability are established by employing the method of Lyapunov functions, so as to be applied more flexibly. The effectiveness of our methods has been shown by computer simulation.

This paper presents a timing extraction algorithm which is based on the near optimum criterion, the near optimum phase appear when the spectrum of sampling signals maximum at f=1/2T.The algorithm has some features, such as fast convergence, the jitter is small, a small amount of computing and so on. This algorithm easily implements on the DSP and has a good application in the all-digital receivers.

Two S-type thermocouples connected to paperless recorder are used to record the temperature change during solidification of the wedge spheroidal-graphite casing. The cool-down time and eutectic temperature are obtained from the cooling curves which are calculated by Pro CAST software. Aided by the image-pro plus software, graphite nodules’ mean diameter and amount can be obtained. Carbon diffusion coefficient of graphite nodule is calculated according to the spherulite growth model. The result is in good agreement with the reference date which shows the validity of parameters. It could provide the parameters for simulation of casting solidification.

To investigate the effect of laminar cooling parameters on temperature field and heat transfer coefficient, an experiment platform for analyzing laminar cooling is designed and made by the author. Making use of the equipment, the cooling experiments with the various cooling conditions have been carried. Based on the experimental results, the effects of different water flows and water temperature on cooling rate are presented in this study. And it can be found that adding impurities into cooling medium is an effective way to improving the cooling rate. The research achievements have a certain reference value for setting parameters in laminar cooling process of heavy plate.

In order to study the distribution of indoor air from wind distributor, the velocity field and temperature field in the room are simulated with AIRPAK software which uses indoor zero-equation turbulent model. To simplify the physical model of wind distributor, five model methods have been used in the modeling process. The indoor temperature and velocity distribution characteristics were obtained and did a comparative study with the experiment. The results of the study show that the model can be simplified largely, simplified model consistent with the experimental data can also save computing resources and computing time in modeling process of wind distributor.

To extend the service life of the equipment, a novel, efficient and cost-effective method is used to recover the damaged component of the equipment. The mechanical properties of unidirectional M40J/epoxy composites, prepared by molding process, were studied. Then the centre-cracked thick LC52CS aluminum plates were single and double side repaired with the composites patches by vacuum bagging technology in which three cure cycles were applied. Results show that a low cure temperature induce a small thermal residual stress. Choosing the cure cycle with the highest tensile strength of single-side repaired specimens, the tensile strength of single-side and double-side repaired specimens enhance 31.50% and 47.29% of that of the unrepaired specimens, respectively. And fatigue life of the double-side repaired specimens extends that of the cracked aluminum plate over 76 times, which is also significantly better than that of the single-side repaired specimen.

A numerical simulation model for vertical-horizontal rolling process in roughing trains is built according to 3-D rigid-plastic finite element method (FEM), which is validated by comparing the simulation results with measured ones of industrial production. The principle of width deviation appearing on head and tail of slab is investigated by the finite element (FE) simulations. A new polynomial short stroke control (SSC) model is developed based on the comprehensive simulation results and the analyzed results show that, at the aspect of width control, the new SSC model is more effective than the two line one.

With the development of the heating industry, the higher level of operation and management are required. Therefore it needs more accurate values of nodes pressure and flow. In this paper, based on the genetic algorithm, In order to realize the improved algorithm, change the rate of cross and mutation according to the fitness. After revising the resistance characteristic coefficient, we can get the more accurate values of nodes pressure. Finally, an example is given to verify the feasibility and validity of this method.

A high precision reverse engineering design method for complex structural component which based on the meta feature is presented. The defining method for minimal discretization meta feature is studied through the case study of an axial compressor’s impeller. Then the evaluation model of matching quality between RE planning and meta features on the basis of feature analysis and fuzzy synthesis evaluation method is put forward to select the optimal RE planning for different kinds of meta features. Combined with the split silicone mould replication method in engineering, the 3D geometry data acquisition is accurately accomplished and the reconstruction of the impeller’s model is realized from the geometric constraint angle of view and the point cloud registration of multiple views technology based on characteristic constraint. The results indicate that this method is effective for improving the measuring efficiency and quality.

The full flow field numerical simulation of the axial-flow pump model is carried out to predict the pump performance based on RNG k-ε model and SIMPLE algorithm and the method of calculating head and efficiency. The numerical results show that the head and efficiency prediction curves have a good agreement with the experimental results. In the optimal operating condition, the prediction error of head is 0.04% and the efficiency error is 0.39% which could meet the requirements of engineering applications. The prediction error based on RNG k-ε turbulence model is larger in the off-design condition owing to the complex flow field of axial-flow pump. The predicted head is lower than the experimental results in the small flow rate conditions and its maximum error is 5.12%, while is higher than the experimental data in the large flow rate conditions and its maximum error is 17.39%. The conclusions will provide the basis and reference for the performance prediction of axial-flow pumps based on CFD.

This study is carried out to characterize the size distribution of exhaust particulate from gasoline engine. Accordingto the results,particulate number concentrations show bimodal size distribution including nucleation and accumulation mode below the range of 50nm in coldstarting. While in hot start state, number concentration with bimodal size distribution different from coldstarting are less than 40nm in size.The distribution of particulate number,surface area and particulate mass characterized by nucleation and accumulation distribution mode goes below 40nm,and the trends go up with the increase of engine speed.

The use of a variety of means of control in the engine combustion temperature in the low load has been more widely used. Although the opacity of the filter paper on smoke (FSN) was used as a standard in many laboratories PM quality parameters measured, but cannot be measured under different conditions the engine size and number of particles in a major change, especially in smaller size The particles on the human body more dangerous trends. So a study of particle size distribution of a heavy diesel engine emission was investigated under the condition of different intake valve closing timing, different EGR, different injection timing and multiple injections.

With the high-speed development of science and technology, the research and application of the humanoid robot receive more and more attention in the field of intelligent robot.Firstly, the important characters of the humanoid robot are introduced in this paper.Then the architecture of the human robot is analyzed and the research works around the world are overviewed.At last, the prospects for the future research and development are described.

After Ni-Al mixed powder is sprayed on surface of pure Fe using oxy-fuel spraying, the as-sprayed coatings are processed by median temperature sintering in hydrogen atmosphere. SEM image and element distributions cross the interface of sintering coating are characterized using scanning electron microscopy (SEM). The results show that the sintering coating have a good combinaton and there is a transition zones of about 10 μm in width with metallurgical binding cross the coating interface. Under the protection of hydrogen, the oxidation-reduction reaction of Fe, Ni and Al could be occurred cross the coating interface, and contribute to combination of the coating interface. In view of the low sterngth of glue, the high adhesion strength coating could not be evaluated by ASTM C633-79. As a result, a modified experimental method and corresponding finite element (FE) analysis was conducted to evaluate the adhesion strength of high-strength coating. The parallel testing between the new method and ASTM C633-79 on specimens with same condition for low adhesion strength coatings has been conducted and the valid is proved.