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Ag/AgCl electrodes as an important sensor are used in modern clinical detection and biomedical measurement, which have been widely applied in electrocardiograph (ECG), electroencephalogram (EEG), electromyography (EMG), electricity impedance technology (EIT) and so on. In this study, the electrode pairs were gel-to-gel connected. After a stimulating current, the alternating current (AC) or the direct current (DC), was injected through the electrode pair, the electrical potential was recorded, then impedance data of Ag/AgCl electrode was obtained. The results showed that the AC impedance of electrode increased, and then gradually decreased with the increase of current size. It was found that the DC impedance data of Ag/AgCl electrode was changed greatly after the electrode pair was injected into the alternating current. With the long time continuous measurement, the AC impedance of electrode pair gradually increased within the 12 hours. However, the significant fluctuations of AC impedance were observed after 12 hours. Comparing with the AC impedance, the DC impedance of electrode pair exhibited a great increase with the increase of measurement time.

A hybrid mobile power supply is developed based on air-cooled Proton Exchange Membrane Fuel Cell (PEMFC) and lithium battery. Pure fuel cell provides a rated output of 25W. With the assistance of lithium battery, the system provides instantaneous power of 50W. The system consists of fuel cell and its controller, lithium battery and its management circuit, power switching circuit, system control circuit and DC/DC convert circuit. The system is designed and realized, the measurement results show that the system works steadily below 50W.

Harmonics of power system seriously affected the quality of electric power. Shunt Active Power Filter (SAPF) [1] which overcomes the shortcomings of passive filter (PF) has become main technology to suppress harmonic. In this paper, structure, mathematic model, detection method and control of SAPF are mainly analyzed and reviewed. With development of key technology of APF, it will have a better application prospect.

Aiming at the problem of the lack of a type of ordnance equipment unit fault location method and based on μC/GUI embedded graphical user interface, a new detection and diagnosis system is designed, which integrates self-inspection, spare part detection, real equipment detection and teaching into one. The system adopts C8051F020 MCU and S3C2440 ARM9 microprocessor, combines the application of data acquisition, LCD touch control & display, serial communications and other technologies to build the hardware system, and constructs a new menu system based on μC/GUI.

The initial buckling displacements are taken as initial conditions to solve the dynamic postbuckling problem. Non-dimensional dynamic postbuckling equilibrium equations denoted by the displacements are derived and solved by use of the finite difference method. The results reveal the regulation that the dynamic postbuckling deformation develops from the initial low step mode to the subsequent higher step modes under elastic compression wave.

The laser welding system is used to weld vacuum glass,the organizational structure of welding joint and the combining performance of the laser welding in different speeds are studied in this text. Under the same laser output power,welding combining performance and organizational structure are ideal both in the speed of 5mm/s and 10mm/s. It shows that laser welding is an effective method of the edge welding of vacuum glass. By comparison with experimental results, better solder welding joint organizational structure and combining performance can be obtained when the welding speed is 5mm/s than the welding speed is 10mm/s. It explains that appropriate laser welding speed is one of the effective methods of optimizing vacuum glass welding under certain laser output power.

The tunnel sprayer with no drift, pesticide recycling as the main feature, reflected increasingly its superiority to improve the efficiency of spray in the hedge frame crop and reduce pesticide pollution. In this paper, it’s infrastructure to tunnel frame stress distribution and optimum design that is static analysis and experimental research on self-propelled tunnel sprayer frame in the ultimate torsion condition.

Trust management is one of the most challenging issues in the emerging cloud computing. A distributed way is adopted to manage and store trust feedbacks data. We propose a credibility-based trust management model that not only distinguishes between credible trust feedbacks, but also has the ability to detect the malicious trust feedbacks from attackers .On this basis, we also present a replication determination model that dynamically decides the optimal replica number of the trust management service so that the trust management service can be always maintained at a desired availability level. The research results have been validated by experimental results.

To solve the problem of long time consuming in the fractal encoding process, a fast fractal encoding algorithm based on RMSE (Root mean square error) and DCT (Discrete Cosine Transform) classification is proposed. During the encoding process, firstly, the image is divided into range blocks and domain blocks by quadtree partition according to RMSE, then, according to DCT coefficients of image block, three classes of image blocks are defined, which are smooth class, horizontal/vertical edge class, diagonal/sub-diagonal class. At last, every range block is limited to search the best matched block in the corresponding domain block class, and the fractal coding are recorded until the process is completed. When searching the best matched block, the nearest neighbor block will be found in the sense of RMSE in the ordered codebook, and the best matched block will be further found in the vicinity of the nearest neighbor block. The experimental results show that the proposed algorithm can efficiently reduce the search space and shorten the encoding time, while achieving the same reconstructed image quality as that of the full search method.

WMN is the abbreviations of Wireless mesh networks. Along with the evolution of WMN, there appears single-radio mode WMN ,dual-radio mode WMN ,multi-radio mode WMN and their mixed mode WMN. Single-radio mode WMN network has the lowest capacity and the lowest cost, dual-radio and multi-radio mode WMN are better than single-radio mode WMN, multi-radio mode WMN has the largest bandwidth and flexibility, and has obtained the large-scale application.

Wireless communications test set is a test instrument widely used in the field of telecommunication test, but it costs much. To satisfy the actual needs of University's practical teaching, the wireless test simulation software is designed and developed. The simulation system uses C# language for development and design. In term of technical implementation, methods such as object-oriented simulation, GDI+ and Monte Carlo methods are used to deal with the complicated design during the simulation. It realizes the simulation test process of the test set, getting the same results between simulation test results and actual test effects. In term of simulation teaching, the system provides several practical teaching and management functions by combining with the actual conditions of university. The simulation system is of strong practicality to be applied in college teaching as wireless measurement simulation teaching software.

Mitsubishi FX2n series PLC's CPU module comes with high-speed pulse output channels. Using these channels, you can achieve position control of stepper motor. This article describes the use of high-speed pulse output instruction on the stepper motor control to achieve the design points. Contents include: key issues of PLC equipment selection, use of pulse command, and the stepper motor selection and setting.

How to model a dynamic road network has great practical significance in a vehicle navigation system. This paper has proposed a simplified time-division based on road network model which implicitly takes into account the delay time at various intersections, the degree of a road congestion and the different road quality, but avoids a complicated calculation and collection for these traffic data. An improved Dijkstra algorithm based on the new model has also been given. The simulation results show that the model can work well and the algorithm is efficient.