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As an important crypto graphical tool, ring signature is able to realize full anonymity and identity protection. Comparison the traditional PKI, Identity-based (ID-based) cryptography is a very good cryptosystem since it eliminates the need for checking the validity of the certificates of traditional public key system. In this work, we propose an efficient ring signature scheme by combining ID-based cryptography and Schnorr signature conception. Our scheme has some advantages for efficiency. In our proposed scheme, no pairing operators are needed in the whole signing phase and the verifying phase. It reduces the signer’s computation cost and increases the whole signature algorithm’s efficiency. In terms of signature’s length, our scheme only needs (n+1)|G| bits. Our ring signature can achieve full anonymity and unforgeability. The security of the scheme is related to two classical security assumptions: computational diffie-hellman problem and discrete logarithm problem.

There is an increasing interest in tea polyphenols, as natural plant compounds, in food products and also in pharmaceutical products due to their multiple health care functions. In this paper, a microwave-assisted extraction method was employed for the extraction of tea polyphenols. The effects of microwave power, heating time, and ethanol concentration on extraction of tea polyphenols were investigated by single factor experiments and an orthogonal experiment [L9(3)3]. Results showed that the optimum extraction conditions were that the microwave power was 560W, the heating time was 30s, and the ethanol concentration was 40% (v/v). The antimicrobial properties of tea polyphenols were also discussed. Tea polyphenols had bacteriostatic activity against Escherichia coli and Staphylococcus aureus. This study may be valuable for the extraction and application of tea polyphenols.

This study proposes a solution to the problems with electric vehicles, which are characterized by short driving range and long time for charging. The battery fast-swap system we studied includes generality power battery, locking system and auto battery pack fast-swap equipment, which only takes owners about four minutes to finish a completed auto power battery swap procedure. At the same time, we use virtual prototyping software hyperworks to evaluate the strength and stiffness of the structure of the battery fast-swap system, all parameters above can meet requirement of mechanical property for electric vehicles. Moreover, we propose a novel business model of “naked car sales-battery lease-battery swap”, which can improve the problem of energy supply in electric vehicle. Particularly, it has a certain significance to perfect the building of charging/battery swap infrastructure standard system.

Based upon the synopsis of software support of information system, this paper puts forward main factors, integrated model and phase tasks of software support of information system, and gives description to software supportability analysis technology, software fault diagnosis technology, software fast recovery technology and software remote support technology so as to increase software support capabilities and information system effectiveness.

In order to realize the industrial computer can control automatic adjustment of linear motor, design the linear motor control scheme based on virtual instrument technology. System driven by the control card of GE series, based on the LabVIEW development platform, realizes the intelligent control of linear motor.

Numerical investigations of the abrasive influence on material removal efficiency of the micro-hole for AFM process is conducted in this paper. A three-dimensional model is constructed for this process. The abrasive with various particles volume fraction and different micro-holes with various diameters are selected in this study. The simulation results show that the lower particle volume fraction may be in favour of the metal removal uniformity, but the processing time will be too long if too low fraction is selected.

This paper discussed the analysis of the regional airport air volume forecast based on the classic GM (1, 1) model in the grey system theory. Focused on the impact of predict of the data by application of the original data sequence after preprocessing by the strengthen operator and weakening operator in sequence operator. Through the analysis and comparison of the concrete prediction of Beijing-Tianjin-Hebei region airport aviation data, found that in the process of predicting of the region Airport air volume, introduction of weakening/strengthen operator by combination with the area practical situation, as the result of the regional airport aviation prediction is conformity with the practical situation and forecasting precision is better.

The TPMS can not only save fuel and protect the tire, but also make the driver more safety. Tire safety is attracting the driver's attention, the United States had developed laws to enforce the TPMS installation in the car and the deadline is in 2008. In this paper, the basic structure and the implement method of TPMS are introduced. The active sensors are already used in most of the TPMS applications. The SAW theory and some wireless passive SAW pressure and temperature sensors which suit for the TPMS application are illustrated, because the passive sensor is becoming the focus in the TPMS research field. Passive SAW sensor is the good choice for TPMS, according to its wireless, passive, zero age rate, small size etc. The wireless passive SAW TPMS is one of the most important research direction. In this paper, some kinds of passive SAW sensor are introduced, which are used in TPMS.

Based upon the intention summary of software quality management, this paper gives plain description of PDCA circulation, software quality scheme, quality control, quality assurance, and quality improvement. Meanwhile, one quality evaluation is put forward. This will benefit the software quality management of information system.

The heading machine is one of the key equipment of coal mine roadway drivage, and cantilever machine applied most widel, A lot of coal roadway floor condition is very poor in our country, so its travel mechanism performance also have a higher requirements. Especially when driving on slopes, frequently, caterpillar not firm grip, and backward. This article is based on crawler and the ground interaction theory optimization model is established, the crawler structure parameters are optimized in order to obtain maximum tractive force,thereby improving the performance of walking.

This article introduces two ways of calculating the transmission parameter of the mechanical system in the aircraft based on the traditional computational method. One is the method of fixed point coordinate which is based on spatial Analytic Geometry and spatial coordinate transformation can calculate the motion parameter of various links, the effective radius of the limit position rocker as well as the transmission ratio by fixed point coordinate. The other method can establish the model of control system by using the MDT module of the three-dimensional mapping software CATLA. It also can realize analog computation and system optimization which points at the transmission parameter of the mechanical system by using DMU module.

Biosorption of As3+ ions by industrial fermentation waste Aspergillus niger free dry mycelium was investigated in a batch system..The influences of solution pH, biosorbent dose, As3+concentration, and contact time on As3+ were studied.The results indicatd that absorption capacity was strongly affected by the solution pH, the biosobent dose and initial As3+concentration.Optimum biosorption was observed to be 75% at pH 5.0,biosorbent dose 20g/L, initial As3+concentration 800ug/L. Adsorption equilibrium was established in 100 min. Biosorption equilibrium data were best described by Langmuir isotherm model.

Over 600 million square meter heating area use the district heating system in Beijing up to 2013. The construction and operation level of many heating systems are diverse. It leads to the difference in the heating energy consumption and cost. The obstacles that impacts on the energy efficiency improvement for the district heating system in Beijing were presented. The primary job to reduce the gross heating energy consumption is to evaluate the energy efficiency of the heating system, reasonably. The aim of the paper was to provide an improved method to evaluate the energy efficiency of a district heat system.The energy conversion between the different typical parts of a heating system was discussed: the source, the primary network, the secondary network, the heat exchanger station and the building. Also, six district heating system in Beijing was evaluated by the method to illustrate the proposed technique.

In allusion to environmental pollution brought about by wastewater irrigation, EM technology was introduced to study the feasibility of EM application in wastewater irrigation. The results show that EC, NO3--N and TN value of EM treatment in shallow groundwater are all less than those of WW treatment as a whole. In all samples, 59.3% NO3--N values are in the alert status, and when irrigation amount reaches 360mm, treatment WW has caused shallow groundwater pollution. TN concentration in treatment WW-3 on June 27 and July 9 is more than 110 mg/L. It suggests that NO3--N can easily penetrate into shallow groundwater with wastewater irrigation and there is insurance of groundwater pollution in the long-term wastewater irrigation. It also indicates that application of wastewater treated by EM reused for irrigation is feasible. TP values are all very low and suggest the pollution of P does not happen.

The wetting behavior of polymer melts such as HDPE, PP, PC, POM and COC on bulk metallic glass material substrates that are used in polymer micro fabrication like micro injection molding was investigated by sessile drop method at a temperature above the corresponding melting temperatures. Contact wetting angles have been determined on three kinds of bulk metallic glasses: Pd40Cu30Ni10P20, Zr64.8Cu15.5Al8.3Ni11.4and La57.5Al17.5Ni12.5Cu12.5. The equilibrium contact angle has the monotone decrease with the increasing temperature for most polymer melts. Two kinds of wetting behaviors are observed, spanning from 126°, over neutral wetting, to 6°, almost complete wetting. Estimations of the contact wetting angles are presented in different polymer melt temperature. Optimization of process parameter can be chosen according to the wetting ability.

Aiming at the absorption effect of fog suspended in the atmosphere on light, the paper established the removing-fog compensation adaptive model which can improve the atmospheric visibility and restore the normal work of outdoor system. The experimental results show that the removing fog image processed by the method of removing-fog compensation optimization can accord with the requirement of human visual, and it can be used in real-time video monitoring as the fast computing speed. The method not only can be used in foggy video which the fog distributed uniformly, and can assess the visual quality for the images processed.

The thesis presents a set of design scheme of grating displacement measuring system by taking SCM (Single Chip Microcomputer) as the core component. It describes the system design principle and the design process of software and hardware in details, i.e. realizing standard TTL level signal output through the processing of grating output signal amplification, sub-dividing, modulation and driving, so that grating output signal could match the numerical control system. It turns out that the designed grating displacement measuring system is able to satisfy the requirement of high-speed sampling and storage and feasible to be used for the measurement of actual grating displacement. The system has a simple and compact structure and a lower price, and owns favorable practical performance.

The finite element model of the combination bracket about solar collector was built and modal characteristics of the structure were analyzed. Wind speed time series was simulated in a given wind speed of the wind power spectrum by AR mode of linear filtering and fluctuating wind load time samples were got in each node on the windward side. The curve of load time series was took as the power input, and the wind-induced response of structures was calculated under random wind loads by the transient analysis. The results show that the large displacements appears on the edge of Collector components along horizontal and vertical direction in the case of fluctuating wind and the greater stress occurs in the joint of the cantilevered brackets connect and the upper end of the torque box, so it should be noted in the design of brackets of solar collector.

PLC (programmable logic controller) is one type of general industrial control platforms. Based on the PLC of SIMENS S7-200 series, this paper introduces a control scheme of cutting metal plates control system in the flame cutting machine. The hardware design and PLC program are given in details, which achieve accurate position and fixed-length cutting by the stepper motor through the control of PLC. In addition, the configuration simulation of the system is performed by the application of King view software. The control system has multiple operating modes, high reliability, stability and is able to meet the variety of different work requirements. The automatic control of cutting metal plates is achieved. The control system is applied to actual projects and can greatly enhance productivity.

The polymorphism is the one of the main features of the object oriented program. The compiler determines the uniqueness of polymorphism by dynamic binding. In a static source code, there will be one function calling point corresponding to several called functions. As the consequence, there will be many redundant function calling paths. It is the key to improve the efficiency of the path coverage test based function call graph with control logic determining the uniqueness of polymorphism. This paper analyzes the feature of the polymorphism in C++ and proposes an algorithm to determine the uniqueness of polymorphism statically in C++. The algorithm can find the unique called function from the several called functions without running the program. The result shows that the algorithm can obtain the unique called function correctly and eliminate the redundant paths. It improves the testing efficiency and reduces the testing cost.

In order to improve precision, outdated measurement method, complicated structure and weak anti-jam ability in liquid level measurement, a set of liquid level system was designed with the core of high-precision laser displacement sensor. The system adopted non-contact laser trigonometric survey method and powerful virtual instrument techniques. It could conduct online and real-time measurement to infinitesimal displacement on liquid level with high speed and precision. Through measurement experiment, its accuracy and practical applicability is verified.

On-line insulation monitoring of transformer and the fault diagnosis are effective means to avoid sudden accidents happening on the transformer, which are necessary to perform the condition based maintenance (CBM) of transformer. Partial discharge is often accompanied by the external signals of sound, light and electricity as well as some detectable physical phenomena such as characteristic gas and dielectric loss. The partial discharge defects inside the transformer can be found by detecting the external signals. The principle of electro-acoustic monitoring, its monitoring systems and the related judgment technologies are expounded, on the basis of which an outline design of the monitoring system is presented.

The electrolyte optimum composition consists of 1mol/L LiTFSI in the [EMIM]+[TFSI]-mixed with EC and DMC in weight ratio of 60:20:20. The LiFePO4/Li cell using 1 mol/L LiTFSI/([EMIM]+[TFSI]-/EC/DMC) as electrolyte show that the first coulomb efficiency was 90% and the first discharge capacity was 168mAh g-1. The 15th reversible capacities were maintain 157mAh g-1at 0.2C. Compared with traditional organic electrolyte and pure IL electrolyte, IL-based mixed electrolyte have good coulomb efficiencies and higher charge and discharge performances. The lithium transference number of IL-based mixed electrolyte at room temperature are 0.59. Thermal stability of IL-based mixed electrolyte higher than traditional organic electrolyte, and show almost non-flammability by the burning tests.

This paper presents a new cycloid permanent magnet gear(PM gear) based on Halbach array, which has the advantages such as extreme torque density and a very high gearing ratio. And the Halbach array can produce one-sided filed that will increase the magnetic filed intensity. The air-gap magnetic field of cycloid PM gear based on Halbach is got by adopting finite element method. At the same time, to research the torque characteristics, the factors which affect the magnetic torque of cycloid PM gear are studied respectively through the FEM, such as torque angle，offset，thickness of permanent magnets and yoke irons.

This paper presents an algorithm of S-curve profile velocity planning with prediction of deceleration distance dynamically, extended functions including target position or target speed change on-the-fly, motion pausing and resuming are addressed. The algorithm is implemented for high performance multiple axes motion controller where complex paths must be employed for each axis to obtain smooth acceleration, speed, position shapes and target position or speed will be changed during moving to meet the requirement of processing. Application that requires the ability to change the endpoint or moving speed without completing the previous move are applied in varied industrial equipment such as SMT, AOI, product lines, etc.

PrefixSpan algorithm will construct huge amount of projected databases in the process of mining sequence patterns, especially mining dense dataset and long sequence pattern, which will cause decline of the performance of the algorithm. The resource problem can be solved by Projection position-based Sequential Pattern Mining Algorithm so as to reduce time and storage space. In order to avoid producing huge amount of projected databases and reduce unnecessary storage space and scanning time, compared with the others improved algorithm, the PSPM utilizes projected position to locate projected sequence position for mining local frequency items and deletes the non-frequent items. Experiment results demonstrate that PSPM outperforms the PrefixSpan(with pseudo-pro) algorithm in the aspect of Runtime performance.

Kinematic characteristics of Hoeken mechanism is analyzed. Variable ratio transmission characteristics of oval gear is obtained. Oval geared Hoeken mechanism is presented. Kinematic characteristics of oval geared Hoeken mechanism is clarified. Eccentricity is optimized. The oval geared Hoeken mechanism with approximate uniform rectilinear motion is designed. The methods in this paper facilitate the innovation design of the mechanism with approximate uniform rectilinear motion.

Some key components’ failure often occurs in the process of the use of large-scale mining coal machine, and seriously affects the production of the enterprise. So it is necessary that analysis on the failure mechanical reason of guide shoes with the coal-winning machine by the modern mechanics analysis method. The stress diagram of guide shoes could be got by static analysis with MATLAB, and the dangerous parts of the finite element model with guide shoes appeared after loading. Finally, analysis on the fatigue strength and fatigue life of components under various complex condition, which provide some reference theory basis for the future related product designing, Manufacturing and maintenance.

According to the usage of vehicle radar antenna pedestal center frame, this article analyzes and compares the structure characteristic of welding and casting. We decide to adopt the casting structure and use special casting material ductile iron QT450-10. And we describe the casting material ductile iron QT450-10. Based on the center frame of using conditions, we analyze the deformation and stress of center frame by the finite element analysis software. The design is in line with the material allowable requirements and to meet the requirements of the system stiffness.

Damage identification method of space rigid frame was based on change rate with the difference of the first axial modal, which applied to the model of space rigid frame on experiment. With extracting the experimental modal data to calculate the change rate with difference of the first axial model, the result shown that the change rate with difference of first axial model increased significantly in the injury site, and could identify well the damage location of single or multiple injuries, which was an ideal space frame damage labeled amount because of high sensitivity, less work of measure and calculation.

Beijing building energy efficiency work has been carried out for 20 years, which played a significant role in building energy saving. Based on the energy audit which is site test and statistics of building energy consumption analyses the energy consumption of residential building in Beijing. Discusses the residential building energy consumption characteristics and gives the energy consumption tread of residential building in Beijing. The results show that Beijing's residential building energy consumption per unit area is reduced year by year, which is mainly related with the implementation of the Beijing building energy efficiency standards.

Use Kingview to acquire and display the centrifugal pump performance parameters for the real-time data, and will stored the collected experimental data in Access databases, using VB database read, and drawing function for the data processing and rendering performance parameters of relationship curves.

This paper investigates the controllability of discrete-time multi-agent systems with leaders via switching topology. The results show that a multi-agent system can be switching controllable even if each of its subsystem is not controllable, by appropriately selecting some agents as the leaders and suitably designing the neighbor-interaction rules via a switching topology. Meanwhile, the controllability of systems can be only determined by the information from the leaders to the followers. Example and simulations are given to illustrate the theoretical results.

Classroom discipline is a complex and variable dynamic process, classroom problem behavior always leads classroom discipline problem that will affect teaching quality. The simulation on classroom discipline of multiagent system based on complex system theory uses dynamic simulation platform NetLogo. The result of simulation shows that this method can reproduce the dynamics of discipline behavior’s three stages in ecological classroom. This simulation provides forceful support for the classroom discipline management of teachers.

Through analysis of abrasive flow machining principle, this paper explores the design of equipment which is suitable for nozzle micro-hole abrasive flow machining. Based on catia，a cad software, three-dimensional models of the parts are drawn and assembled together. Based on the Finite Element Simulation software ansys, the finite element analysis of the key components of the equipment can be achieved. Through the result of simulation, the design of the equipment is reliable, and is able to satisfy the requirements of strength and rigidity. It offers the theoretical basis for optimizing abrasive flow machining equipment. Through the result of tests, the system of the equipment runs steadily and the ideal abrasive flow machining effects can be achieved.