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The broaching process is widely used to generate irregular internal and external part features, therefore there is a demand for a broach with good broaching performance. Aiming at slowing broach surface wear degree and improving the tool life, this paper puts forward a inverted triangle textured broach which is based on the theory of metal cutting, friction study and contact mechanics. The broaching 45# steel load experiment was carried out. The broaching force and surface morphological changes were measured, and the cutting performance and wear characteristics of the textured broach tooth were analyzed by comparing with ordinary broach. Results show that the inverted triangle textured broach can reduce broaching load by 5%, and improve the response performance of broach for broaching load. The wear area and wear quantity of ordinary broach were larger than textured broach. The textured broach can greatly improve the cutting efficiency, reduce the tool wear and increase lifespan.

When using the laser displacement sensor to measure distance, there is a deflection angle which exites between the direction of the laser beam and the direction of axis, this deflection angle has an impact on the final measurement result. This paper presented a calibration method of the laser beam’s direction, designed calibration device and ceramic calibration plate. In the process of calibrating, laser displacement sensor moves along Z-axis and Y-axis of machine, CCD camera takes the image of the spot projected by laser beam on the calibration plate, then calculate the laser beam’s direction based on the movement distance of laser displacement sensor and the spot’s position on calibration plate. Depend on the Mikron five-axis CNC machine tools, this paper describes the whole calibration process in details, the feasibility and accuracy of the method has been verified by experiment. Experimental results show that when the machine tool’s accuracy is within 0.002mm, the calibration error of laser beam’s direction can be controlled within the range of 0.05°.

There is an increasing concern about the threat of Waste Electrical and Electronic Equipments (WEEE) generating in China. The Chinese government had made a series of regulations and policies to address this problem. However, these practices are more focusing on the environmental protection rather than the resource utilization. Since WEEE is also a valuable kind of renewable resource, this essay will try to understand the current situation of WEEE recycling and resource utilization technologies and equipments. In the year of 2014, China Household Electric Appliance Research Institute conducted a questioner research targeting the 91 subsidy funded companies, which received 50 responses. By the comparison of previous studies of this issue and the analysis of the data collected, resource utilization situation of the industry can be addressed. This essay will also explore an evaluation model to assess the resource utilization standard of WEEE recycling. Based on the analysis, nine outcome criteria and evaluation strategies are formed to judge the resource utilization standards of WEEE recycling companies. This evaluation model will target all the life cycle of WEEE, and include criteria such as recycling technology and equipment, management standard, and resource utilization level.

The performance of automobile drive axle housing structure affects whether the automobile design is successful or not. In this paper, the author built the FEA model of a automobile drive axle housing with shell elements by ANSYS. In order to building the optimization model of the automobile drive axle housing, the author studied the static and dynamic performance of it’s structure based on the model.

Based on the coupling of PC-Crash program and MADYMO software, thekinematics laws of pedestrian in the contact process for automobile-pedestrian collision are analyzed through modeling and simulation by establishing vehicle model and pedestrian model, and selecting main influencing factors on contact phase as independent variables for simulation tests.

Software engineering risk is an important issue in software engineering research and the formation and measuring of software risk is also a difficulty. Since the risk transmission effect is not considered in traditional software projects, based on risk element transmission theory and hidden Markov model, a new model called Hidden Risk Markov Model was proposed. The model takes into account the effect of software engineering risk transmission in different prototype stages on final software engineering risk and uses the observable risk element transmission to calculate the degree of engineering risk. Finally, an example of software engineering risk control was presented.

In this paper, we focus on the defects of traditional business model, and give the self-similar process definition and significance of research. The self-similar process and characteristics is introduced, and the affected network performance is presented. In order to better understand the network model, we establish an effective business model based on the Poisson and Markov model. A novel iteration approach is introduced to solve the deficiencies problem of traditional approach, it is quite suitable for the dynamic p-cycle application and can accurately describe the actual network traffic for real network. Finally, the precision of different prediction algorithms are compared and analyzed.

With the increase of requirement for the quality of raw materials in industry, surface defect inspection of steel bar has been an essential part of industrial production. The characteristics of vision-based detection technology for steel bar surface defect and the newest research development were introduced. The working principle of vision inspection technology and key issues were analyzed. Finally, the current domestic research emphases and development trends were proposed.

Saddle-shaped cable structure is a new form of prestressed structure. Its reliability need to be analyzed for a new type structure. According to the different failure modes, the finite element model of prestressed steel structure is established. By using APDL language, the program is created. Finally, the reliability index of the model for different failure modes is got by reliability analysis. The results Provides reference basis for mechanics performance evaluation of prestressed structure.

The subject of this paper was the presentation of a holistic, fully-temperature-coupled FE model of inertia friction welding based on the modified friction law, which divided the friction welding process into beginning friction stage and steady equilibrium friction stage. At each of the stage Coulomb friction model and shear friction model were adopted respectively. The present FE model predicted the temperature of the welding joint as well as variation of friction torque and relative rotating velocity of the work-piece during the welding process. The evolution of friction torque and rotating velocity were compared with the experimental measurement. They showed a good agreement between them.

This paper analyzed the mechanical properties of the web opening nodes on the steel frame which considered the combined effects, with the finite element analysis software ABAQUS . When the structure with the web openings withstood static loads,formation process of plastic hinge was also analyzed. By applying a load-displacement curve at the endpoint of the main beam, the impact of the flange thickness ratio on the seismic performance was researched. The results showed that reducing the flange thickness will decrease the structural capacity, while the improvement of hysteretic performance was not significant. However, reducing the flange thickness and increasing width of the flange at the same time would not only increase the structural capacity, but also improve the hysteretic behavior and the seismic performance of the structure.

This template explains and demonstrates the interactive mode between electric vehicle and household electricity including photovoltaic power generation.The paper explores it from background and basic conditions, interaction analysis and control strategy, simulation and benefit calculation.

Based on the experiments on noise and vibration of turbocharger, useful information of these signals were extracted. It is found that the noise distribution, loudness, axial vibration and other information could be used to monitor the turbocharger’s quality.

In this paper, an automobile collision avoidance system based on video image processing is proposed for vehicle active safety. Firstly, considering the requirement of real-time system, FPGA is responsible for the core task of video image processing. In the process, this paper introduces an image segmentation algorithm to extract the Region of Interest, a fast median filtering algorithm and an improved adaptive threshold Ostu segmentation algorithm. Secondly, in the design of alarm system, we use the STM32 chip which is based on Cortex-M3 kernel as the embedded platform. Finally, in order to analyze the data obtained by image processing and make smart decisions on the embedded platform, we establish a double parameter alarm mechanism of automobile security model. It can help the drivers to take appropriate hedging measures. The system in this paper has the characteristics of low cost, real-time and high reliability. Through the debugging and experiments, the system has reached the expected effect and met the requirements of automobile collision avoidance system.

A kind of breakdown diagnosis algorithm was proposed based on Ant colony algorithm. The problem of fault identification and classification was translated to a constrained optimized clustering problem under certain conditions in this algorithm. It was applied to the process of fault diagnosis of a hydraulic system. The results show the algorithm is valid and reasonable.

This paper takes Unit Commitment with Wind Power Electric Systems for instance and studies the application of relevant indicators in the short run adequacy decisions. It first conducted running adequacy assessment of the RBTS system, and then given unit combination solutions in the ample index constraints. The results show that the relevant indicators can be more accurately to depict the influence of random factors on system operation adequacy, and Unit Commitment decisions based adequacy index is able to give a unit commitment program at different adequacy levels. The research results provide a set of assessment indicators and assessment methods for short running adequacy problems of random fluctuations power accessing to large-scale power systems..

This paper discusses the necessity of the management for power enterprise trainer. It proposed the use of intelligent computer technology to build electric power enterprise trainer management system according to the current status of the work of power. This paper analysis the current needs of the power of corporate trainer and proposed the overall architecture of power enterprise trainer management system, and design the function of each subsystem.

The semisolid shear rheological characteristic of AZ91D alloy were investigated. The results show that: during the shear rheological test at 570 °C, a critical shear stress and a maximum shear stress are happened. And with holding time increasing, the solid fraction decreasing and the solid particles distributing more uniformly, the rheological rate increases but the critical and maximum shear stress decrease. At last, based on rheological theory, a five-component rheological model of the semisolid AZ91D alloy is established, which is H1 - (N1 / H2) - (N2 / S).

The application prospect of conductive rubber composite is introduced. The mechanism of resistance relaxation of conductive rubber composite was expounded. Several representative mathematical models of the resistance relaxation effect of conductive rubber composite were introduced. The influence of external temperature, heat treatment temperature, the amount of conductive filler, the type and the size of stress, nanomodified materials and dispersing additives on the resistance relaxation effect of the conductive rubber composite were discussed respectively. Finally, a brief description of the application status of conductive rubber composite and its summary and outlook were made.

Since the maritime traffic accidents and oil spill risk problem is getting increasingly serious, on the base of the maritime and oil spill accidents historical data analysis, the risk source in the Bohai Sea is discretized into finite cell. The risk analysis in matter element analysis method has been used to determine every cell’s level of risk and the demand for cruising power of each risk point has been evaluated. The specific location to build maritime unmanned aerial vehicle (UAV) cruise base needs to go through a cost-effectiveness analysis. Taking the relationship between risk point and cruise base’s location into consideration, the multi-target site selection model of UAV cruise base has been established. In this model, genetic algorithm has been used to optimize the site selection and finally, it is able to provide decision-making suggestions for the planning and construction of the Bohai maritime UAV cruise base.

The conductive silicon rubber samples have been prepared in different filler ingredients, the platform is builded for testing the piezoresistive characteristics of conductive silicon rubber when the material is under water pressure and the test methods are designed, the body piezoresistive properties and surface piezoresistive properties under the water pressure within a certain range are studied respectively. The results show that, the sample of 6% acetylene black/2% nanoSiO2 blends exhibit the best piezoresistive performance when the samples are under water pressure, the piezoresistive properties of the material can be improved with the increase of the thickness of the materials (2mm-4mm), and the conductive silicon rubber used for the pressure-sensitive materials of piezoresistive gauge is feasible.

The fault diagnosis of electrical control system of certain type mine sweeping vehicle is difficult due to its complex structure and advanced technique. So in the multi-sensor failure diagnosis process, as a result of various reasons, such as the existence of measurement noise, diagnosis knowledge incomplete and so on, it makes the fault diagnosis uncertainty and affects the reliability and the accuracy of the diagnosis result. This article according to the analysis of electrical control system's fault characteristic of the mine sweeping plough’s, proposes a technique based on data fusion fault diagnosis method. The diagnosis process is divided into the sub system and the system-level, the subsystem uses the BP neural network to classify the fault mode, the system-level uses the D-S evidence theory carries on the comprehensive decision judgment for the whole system's fault. Application shows if some sub-neural network diagnosis has error, using D-S evidence theory fusion can effectively improve the accuracy of diagnosis.

The stability of the concrete shear wall is composed of the overall stability and wall limb local stability, the overall stability and local stability calculation formula can be used the same form of expression. Based on the theory of stability calculation of elastic thin plate, the trilateral bearing and quadrilateral bearing wall limb length factor is derived. And then, it pointes out the disadvantages of the current code and design software, and gives the corresponding solution.

Based on one 240-meter-high special-shaped RC chimney, the structure’s dynamic performance and elastic-plastic seismic response analysis has been studied in detail. From the analysis, it demonstrates the weak areas in the chimney. The interlayer displacement angle about corresponding performance points under four kinds of loading mode were also acuired, and the response of four loading patterns were analyzed.

The paper introduces a disaster tolerant system based on B/S mode and proposes a safe and effective communication protocol that combines with communicational needs. The protocol has been realized in this paper. This system has adopted remote management based on Web so that its construction is reasonable and operation is convenient. Through test,the system which is excellent in performance and stable in working is considered to be valuable for application and promotion.

Demand response provides many benefits in financial and operational aspects for the power user, load management unit and the grid operator. In this paper, we have extended the traditional specification in distribution system automation IEC 61968 to support further demand response service. There are some basic modules and packets have been defined to update traditional metering device, and also the newly added controlled object have been involved. At last, we have take time of use price to illustrate the performance of a wide area demand system by integrating a new controlling algorithm and the results show that it can significantly improve the performance of electricity devices in a home area network.

In order to induce embryo from callus and set up the integral somatic embryo induction system from monoclonal cell, the differences of cell morphology and structure from different types of alfalfa callus were observed and compared by quick section and microscopic examination. The results show that giant callus cells were larger, elongated and yellow-white; loose callus cells were smaller, spherical, soft and yellow-green; hard-type callus cells were round, hard and dark green. The cell volume of giant callus was 4.5 times more than loose callus cells and 9 times more than hard-type callus cells. The biggest change of vacuole number and form were giant callus cells, which had 48%cells of 5-8 big vacuoles. Loose callus cells had 89%cells of 2-4 small vacuoles and hard-type callus cells had 97% cells with one large central vacuole. Loose callus cells had more chloroplast, which were 4.65 times more than giant callus cells. The chloroplast of hard-type callus cells was gathered into groups, which had 3-5 chloroplasts in it. The most nucleuses of giant callus cells and loose callus cells were located in the central of cell and 96.8% nucleus of hard-type callus cells were located on the edge. In hard-type callus cells there were different number of rings, thread and textured ducts. In short, there were lower cell differentiation and clearer vacuolization in giant callus, and high degree of differentiation and tissue aging in hard-type callus. The loose callus was undifferentiated, was lower on vacuolization and apparent on characteristics of embryonic callus, so that it was more suitable for induction of somatic embryos.

This paper studies the different diameters of tube outlet how to affect the gas flow pressure and velocity distribution in nanofiber catalytic converter by CFD (Computational Fluid Dynamics) method. Geometric model of the catalytic converter has been established and meshed by the pre-processing tool of FLUENT. The distribution of velocity and pressure in the converter which outlet diameter is 70 mm is more evenly than the converter which outlet diameter is 50 mm. It is conducive to reducing airflow static pressure in the catalytic converter that expanding the outlet diameter in the case of other conditions remains unchanged. Therefore, the larger outlet diameter is beneficial to exhaust catalytic reaction.

The dry sliding friction test of normalized T10 steel against hardened quenched and tempered 20CrMnTi steel under normal load of 60 N and sliding speed of 0.29m/s was carried out on a pin-on-disc tribo-tester. The microstructures in the worn surface layer of T10 steel pin and 20CrMnTi steel disc were analyzed by OM, SEM, and TEM, which were all severely plastically deformed. The ultrafine and even nanoferrite grains (5 nm to 200 nm) were observed in the worn surface layer of T10 steel pin, which was considered to be the result of severely shear deformation.

As for MEMS Micro machined accelerometer, biases characteristic always varies with temperature fluctuations. Through establishing the error model between the MEMS accelerometer biases and the temperature variation in the temperature range of-20 °C ~ 60 °C, studying on the bias changed with thermal variation of MEMS accelerometer, and the test results show that MEMS accelerometer bias caused by temperature change have decreased from more than 5mg to lessen than 1mg before and after compensation. Also based on the temperature error model of the MEMS accelerometer bias in static and dynamic condition, the whole temperature characteristics have been improved to some extent, which would improve the precision in the inertial navigation systems.

This paper reports a study on vertical distribution characteristics of phosphorus speciation in samples collected at four sites from Baihua Lake, based on the Standards, Measurements and Testing (SMT) programme. In this study, the total phosphorus (TP) concentrations of these sediments samples varied from 944.86 to 2591.56 mg/kg and inorganic phosphorus (IP) was the main phosphorus fraction. For this heavily contaminated sediment, the IP mainly consisted of the Fe/Al-P. The vertical variation of the phosphorus had a tendency to decrease with the depth at sites JYS and YPZ. Since the concentrations of the TP in sediments were high and the phosphorus release potential and bioavailability were significant, the lake is still facing an ecological risk.

In recent years, construction enterprises’ poor economic performance and the drain of senior technical personnel have been two cause-and-effect problems, which seriously restrict the enterprises’ long-term development, and the existing researches contribute little to solve the problems for managers. Considering the uncertainties of talents resource demand resulting from the difference of Multi-project schedule, a cyclic queuing theory of fixed number of customers was introduced from the enterprise management level. Then the risk loss curve and waiting loss curve could be simulated according to historical data and management experience. Finally, a best method to allocate the shortage of technical talents came out. The model was built throughout the management processes, so it owned not only high theoretical basis but also high operability, and has a better reference on solving the two construction enterprises problems.

This paper studies on the eigenvalue[1-5] of the a class of upper triangular matrix with linear relation. It discusses the feature of existence and uniqueness of matrix via two given two characteristic pairs(λ,χ),(μ,γ) . Solutions and expressions are provided under satisfied conditions. The possibilities are exanimated by numerical example.

In China, closed caption is the latest technology standard separating the caption from the image. In current digital television system, it is an urgent issue to be resolved that how to implement the real-time transmission of closed caption with its host video. This paper proposed a kind of closed caption and its representation method. It also designed a closed caption data structure based on XML and provided a solution about how to package XML file and XML Schema file into MXF files.

Partial discharge (PD) detection using UHF signal is a well known advanced detecting method in GIS and has been actively studied. Numerical simulation using finite difference time domain (FDTD) algorithm is performed to investigate the transmission characteristics of W-M waves excited by partial discharge through straight closed tank of a GIS bus in. The time domain decaying characteristics and frequency domain resonance characteristics is studied in this paper. The simulation results shown that for the closed tank, E-M waves attenuate little during transmission and distribute oscillating in the tank. The distributions are symmetrical at 0 degree and 180 degrees and the energy at the two types of degrees is the same.

Three model specimens of alkali-activated slag concrete filled steel tube (AAS-CFST) with different axial compression ratio and steel ratio were designed and tested in the present study. The seismic performance of the structures were evaluated by testing them with combined lateral constant compression and vertical cyclic loads. The structural performance, such as the testing observations, hysteretic behavior, skeleton curve, stiffness degradation, energy dissipation capacity and ductility performance was discussed in detailed. The results show that all the specimens’ damage were bending deformation mode, and the hysteretic curves are relatively smooth. Test data indicated that increased the axial compression ratio improved the load bearing capacity, initial stiffness.

The rudder and steering gear is the most widely used ship maneuvering equipment. It consists of the maneuvering device, transmission mechanism, steering gear, steering mechanism and the rudder blade. MV "TANSUO HAO" is a scientific research ship of 30 years old. The scientific exploration missions require a very high accuracy of the ship’s course, so the ship has to constantly adjust her course and steer frequently. On that day, the duty officer found the steering gear failure to turn left in the rough sea condition. The engineering crew members had to make an emergency repair. It took plenty of time to locate the trouble of the steering gear in the repair process, because the valve plate deformation problem on the solenoid reversing valve was very hard to find out. By exploring the obscure steering gear failure reason and special troubleshooting process on MV "TANSUO HAO", this thesis provides some repair experience for the hydraulic system management and proposes flexible and patient failure analysis as well as some preventive maintenance measures against the problem.

Facial region detection has broad application prospects, but existing human face region detection methods have some rigorous requirements for the light conditions. Error detection about face area caused by the poor light conditions has a great bad effect on the follow-up processing, such as face recognition, fatigue degree evaluation based on visual. So face region detection in complex lighting conditions has always been the difficult problem. Therefore a self-adaptive illumination compensation method for color images has been proposed. Select the color face images database of the California Institute of Technology to test the method dealing with the face region detection by original image and the image after illumination compensation. In the simulation experiment, the method of Illumination compensation can effectively improve the detection accuracy. Lay the foundation for driver fatigue detection based on visual.

Currently shipping costs are increasing sharply due to the rising oil prices. In order to reduce shipping costs, most low-speed two-stroke diesel engines run at low speeds to reduce fuel oil consumption, and this measure might result turbocharger surge. For modern marine diesel engines, the exhaust gas turbochargers are becoming more and more important; their working conditions have a direct impact on the performance of diesel engines, consequently affecting the operation of the ship. Surge will fail a turbocharger to achieve the supercharging ratio, damage the turbocharger components and even lead to a damage accident of the whole turbocharger. Therefore, a good understanding of the reasons for marine diesel engine turbocharger surge will help to prevent and eliminate turbocharger surge in operation. This paper is to make an analysis on the special surge mechanism occurred to the turbocharger on MV "Crystal Star", and propose some appropriate supervisory and preventive measures against the problem.

The election of cluster head (CH) in LEACH lead to CHs nonuniformed distribution and energy consumption disequilibrium and some of the network nodes dead earlier. For the disadvantage, a kind of improvement algorithm based on geography and energy for LEACH router protocol was put forward in this paper, and simulated in the NS2.The new algorithm makes the CHs located in the center of the cluster, avoiding part of nodes far from CH wasting too much energy,and then.The simulation shows that the improved LEACH protocol is more energy-efficient than LEACH, and can prolong the network lifecycle.

With the development of national fitness activities, stadiums with all kinds of standards are established across the country. The functions of illumination and refrigeration inside stadiums have applied electricity. In order to save the consumption of energy, keep the sustainable development of society, as well as reinforce the consciousness of environmental protection, the thesis designs a set of novel light guided automatic lighting system of solar energy. The system realizes indoor illumination with controlling system. In the daytime, the system uses optical materials with automatic following lighting for indoor illumination, while uses stored energy of storage battery provided by daytime solar panel for LED illumination. The solar cell also provides energy for daytime automatic following lighting device. This device can take full advantage of solar energy to deal with the problem of energy waste, as well as proposes a new idea for energy conservation and emission reduction for stadiums.

A novel composite catalytic membrane as heterogeneous acid catalyst for biodiesel production was prepared from zirconium sulfate (Zr (SO4)2) and sulfonated poly (vinyl alcohol) (SPVA) solution supported on/inside PET non-woven fabrics by the phase inversion method. Membrane structure was characterized by Field Emission scanning electron microscope (FESEM). The effect of polymer concentration on membrane morphologies was investigated. The catalytic performance of the composite membrane demonstrated an increasing from 73.04% to 56.72% with the increasing the membranes porosities increased from 37% to 68%. And the optimum molar ratio of methanol/oleic acid to produce methyl esters was 3:1.

The exhaust heat loss of the power plant boiler can account for more half of the boiler heat loss, exhaust gas temperature is 110~160 °Ccommonly, so the exhaust gas heat can be used to reduce the coal consumption, raise the economic benefits. Before and after the desulfurization tower of a 350 MW unit, there installs two plate heat exchangers, heating condensation water respectively, which can improve the thermal efficiency. With two heat exchangers working under the design conditions, a test was carried out based on a 350 WM unit simulation system in order to test the influence of system for unit operation characteristics. Referring to the data, the investment of the heat exchanger can achieve 2.68 g/kWh coal saving during the non-heating period and 0.2531 g/kWh during the heating period.

A kind of design scheme of PTZ control system based on DC torque motor was proposed to improve fast tracking ability and tracking accuracy of moving target. The mathematical modeling methods for each link were given and the parameters were determined with the help of engineering design method. The simulation results showed that the system had higher location accuracy, better tracking performance and could satisfy the design request.

Dynamic characteristics of the structure have a significant effect on the performance of the structure. Modal test is a common method to obtain structural dynamic characteristics. However, due to the mass effect of the transducer, the measured results of lightweight structure are inaccurate. This paper proposes using strain gauges to test the mode of lightweight structures, and we take the cantilever beam as an example. The paper derived strain modal expressions. We use the strain gauges, the accelerometers and the finite element simulation to test the modal of the cantilever. To compare and analyze the experimental data, it illustrates that the strain modal test methods can measure the bending mode of the beam effectively.

A sulfonated polyethersulfone (SPES)/polyethersulfone (PES) blend catalytic membrane was prepared and used as a heterogeneous catalyst in the esterification of oleic acid with methanol for producing biodiesel. Response surface methodology (RSM) based on central composite design (CCD) was used to optimize the three important reaction variables methanol/oleic acid mass ratio, catalytic membrane loading and reaction time for the esterification by SPES/PES blend catalytic membrane. The optimum condition for the esterification was as follows: methanol/oleic acid mass ratio 1:1, catalytic membrane loading 1.66 meq/g, reaction time 6 h. The optimum predicted fatty acid methyl ester (FAME) yield was 97.44% and the actual value was 98.64%. The above results shows that the RSM study based on CCD is adaptable for FAME yield studied for the current esterification system.

Under the bad environment, high polymer wear-resistant material has more superior erosion wear resistant performance than metal. It can replace wear-resistant metal material partly. In this paper, high polymer wear-resistant coat has been prepared with the epoxy resin, low molecular polyamide, nanoAl2O3coupling agent. The shear strength and wear resistant test has been carried out under different elements content, and the test curve of coat is given. The results are analyzed. By the experiment result, the optimum coat formula is: low molecular polyamide content is 60% relative to E – 51; and the content of MoS2is 12%. The result shows that the coat erosion wear resistance is 9 times of 45# steel under the best recipe. The coat is used to repair a worn mortar pump impeller, and the effect is obvious.

Though Cloud storage has developed rapidly in recent years, there still exist some problems obviously. Provable Data Possession (PDP) is proposed to solve the problem of data integrity verification at untrusted cloud stores. This study built a new delegation Provable Data Possession (delegation-PDP), which solves problem when the client has no ability to check its remote data. We study the delegation-PDP and use proxy re-encryption to design it. Then we use the improved Elgamal-based algorithm to implement the scheme. Through security analysis and performance analysis, our protocol is provable secure and efficient.

Simulations on the dynamics for the transmission shaft-rear driving axle of minibus were conducted with ADAMS. By using ADAMS software, the multi-dynamic model of the transmission shaft-rear driving axle was set up and then effects of the equivalent transmission shaft angle’s variation and transmission shaft rotating speeds on the rear driving axle’s vibration were analyzed. With the increase of the equivalent transmission shaft angle’s variation and transmission shaft rotating speeds, the vibration of the rear driving axle will also increase. These simulation results will give help to further study of the NVH characteristic of the rear driving axle.

At present, hierarchical routing protocols have been the main solution of routing scalability problem in MANET. Based on the deep research on hierarchical routing protocols, hierarchical routing protocols were divided into two parts. The situations of the main routing protocols of each part were reviewed and analyzed. This work will contribute to the further study of hierarchical routing protocols.