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The audiometry of the signals of VTAMVDR trackable targets is studied. The process of the audiometric signals of VTAMVDR trackable targets is presented. Applying the linear proportional overlap-add method to acquiring audiometric signals output from vector linear array beams ensures the extracted signals are continuous data streams, solves the problems about splicing points in audiometry by use of VTAMVDR and retain the better detection performance of VTAMVDR.

The control precision of gimbal system for a Control Moment Gyro(CMG) is a main factor affecting the output torque accuracy of the CMG.Generally,a harmonic driver a harmonic driver is adopted to improve the dynamic response ability of the gimbal system,however,the induced mechanical resonance seriously reduces the control precision of the gimbal system.In order to eliminate the resonance and satisfy the control precision of the gimbal system,a kinetic model was set up.A proper damping ratio was chosen to design the dominating poles according to the demands of gimbal system for dynamic performance.The zeroes induced by a controller were calculated to be equal to the poles induced by mechanical resonance,so that the mechanical resonance was eliminated.Simulation and experiment results show that the proposed method eliminates the gimbal resonance of the CMG,and the control precision of 0.175 rad/s is 0.002.When the gimbal system tracks a 0.175 sin(2πt) rad/s sine given velocity,the relative amplitude error is 3.28% and the phase error is 0.13 rad.The control performance satisfies the demands of CMG for high output torque precision very well.

A CMOS full differential interface circuit with low noise and high linearity was presented for closed-loop capacitive micro-accelerometers.Based on switched-capacitor detection,the circuit was designed to improve its linearity by a 0.5 μm n-well CMOS process technology.The simulation result shows that the proposed two-path feedback structure provides a good system linearity of 0.01%.The optimized designed PID controller was added into the system,which decreases the stabilization error effectively,increases the system responding speed by 31%,and the linearity by 66.7%.With a ±5 V supply and a sampling frequency of 64 kHz,the circuit can offer the equivalent input noise in 8 μg·Hz-1 2,system sensitivity in 1.22 V/g,system linearity in 0.03%,and the work range in ±2 g.These results prove that this circuit is suitable for applications of high performance micro-accelerometers to seism detection,oil exploration,etc..

To overcome the influence of the nonlinear friction on the gimbal servo-system of a double gimbal control moment gyro with harmonic drivers,the methods of modeling and compensation of the nonlinear friction are proposed.Firstly,the relationships between the nonlinear friction torque and the angle acceleration of a gimbal motor and the friction torque and the current of the gimbal motor are deduced according to the mathematical model of gimbal servo-system.Then,based on the angle position measured by encoders,the angle velocities of the motor and loader sides are calculated and an angle acceleration estimator is designed to estimate the angle accelerations of the motor and loader sides.Furthermore,the nonlinear friction torque is calculated and modeled as the Coulomb,viscous and Stribeck friction model.Finally,a feedforward compensation controller based on the model is designed to restrain the nonlinear friction and to improve the control precision.Experimental results indicate that compared with those of the conventional PID control method,the peak-peak value of angle velocity error curve has decreased by 28.2% and the mean squared error decreased by 25.7% after the feedforward compensation controller is added.It concludes that the feedforward compensation controller decreases the angle velocity error caused by nonlinear friction and improves the control precision of the servo-system.

Inorganic-organic metal halide perovskite solar cells (PSCs) have drawn tremendous attention as a promising next-generation solar-cell technology because of their high efficiencies and low production cost. Since the first report in 2009, the recorded power conversion efficiency (PCE) of PSCs has rapidly risen to 22.1% by using 2, 2', 7, 7'-tetrakis (N,Ndi-p-methoxyphenyl-amine) 9,9-spirobifluorene (spiro-MeoTAD) as hole transport material (HTM), with the efforts devoted to the device architecture optimization, material compositional engineer and interface engineering. Nevertheless, the synthesis and cost of the organic HTM (OHTM) become a major challenging issue and therefore alternative materials are required. In the past few years, the applications of inorganic HTMs (IHTMs) in PSCs have shown large improvement in PCE and stability. For example, PSCs with CuOx as IHTM reached a PCE of 19.0% with better stability. Even more exciting, the theoretical PCE of PSC based on Cu2O HTM reaches 24.4%. So, Cu2O is a promising IHTM for future optimized PSC and the large area uniform preparation is very important. In this paper, Cu2O films have been successfully prepared using electron beam evaporation followed by air annealing. The influences of annealing temperature and time on the composition, structure, and photoelectric characteristics of film are investigated in detail. It is found that the as-deposited film is a mixture of Cu2O and Cu. With the increase of annealing temperature, material composition is transformed from mixture to pure Cu2O phase, and then to CuO, due to the oxidation in air. In an annealing temperature between 100℃ to 150℃, pure Cu2O film can be obtained with an average transmission rate over 70%, optical band-gap of 2.5 eV, HOMO level of -5.32 eV, and a carrier mobility of 30 cm2·V-1·s-1. When the film is treated with a UV lamp, the structure and composition of the film can be changed more easily because of the enhancement of oxidation. Finally, reverted planar PSCs with the structure of Ag/PCBM/CH3NH3PbI3/HTMs/ITO are constructed and compared carefully based on HTMs of Cu2O, with poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS), and Cu2O/PEDOT:PSS layers, respectively. An optimum thickness of 40 nm of Cu2O HTM is achieved with high carrier extraction rate. However, the performances of all of the PSCs are inferior to those of PEDOT:PSS-based devices, due to the formation of pinholesin absorber layer resulting from the strong hydrophobicity of Cu2O film. However, the efficiency of PSC based on Cu2O/PEDOT:PSS double-HTM is deteriorated because of the chemical interaction between PEDOT:PSS and Cu2O. These findings provide some important guidelines for the design of HTMs.

In cognitive radio networks,We usually use nine scaling law based on multi-attribute utility theory as a common spectrum decision mechanism.the traditional scale method only consider the spectrum own objective properties and then makes judgments is not comprehensive enough. This paper through researched the mechanism of scaling judgment in psychology, a new and improved scale method were proposed, and the new scale method applied to spectrum decisions ofcognitive radio networks, So that the measure of subjective judgment factors are more scientific and makes more explicit determination in spectrum decisions. Finally through calculate consistency index to verify the superiority of the improved scaling.

To improve the efficiency of energy harvesting, this paper presents a tri-stable energy harvesting device, which can realize inter-well oscillation at low-frequency base excitation and obtain a high harvesting efficiency by tri-stable coherence resonance. First, the model of a magnetic coupling tri-stable piezoelectric energy harvester is established and the corresponding equations are derived. The formula for the magnetic repulsion force between three magnets is given. Then, the dynamic responses of a system subject to harmonic excitation and Gaussian white noise excitation are explored by a numerical method and validated by experiments. Compared with a bi-stable energy harvester, the threshold for inter-well oscillation to occur can be moved forward to the low frequency, and the tri-stable device can create a dense high output voltage and power at the low intensity of stochastic excitation. Results show that for a definite deterministic or stochastic excitation, the system can be optimally designed such that it increases the frequency bandwidth and achieves a high energy harvesting efficiency at coherence resonance.

The underwater sound radiated by vessels consists of deterministic mechanical sounds, propeller noise and hydrodynamic noise. Though many methods have been done to control the sound radiated by vessels, flow noise is always present around a moving vessel. Time-frequency analysis is often used as a method to observe energy distribution of ship noise. In the time-frequency distribution picture of surface ship noise, parabolic patterns are evident. They are caused by multipath transmission of vessel noise. In the paper, using interference spectrum for target detection is discussed. And the superimposed interference pattern is utilized to find moving vessel range. Finally the speed and the closet point of approach estimation of a moving vessel is given using the method.

This paper describes the architecture of a ship monitoring system based on WebGIS and how we solved two critical problems we encountered during the development — integrated reading of three formats of maps (S-57, TAB and Shapefile) and dynamical display of 3000 ships on the maps. The platform(MapServer) and libraries(OpenLayers and ExtJS) we used for developing are all open-source.

With the development of market economy and the urbanization advancement, the 'unit person' transforms to the 'social person', the importance of community informationization construction highlights unceasingly. This paper takes communities in Wuhan as an example, investigating the main public groups who need the GCI and the main information they need by empirical research methods. Finally it points out some problems on the service of the GCI and gives countermeasures guided by the results of the survey.

PID controller has the problems of inferior dynamic quality and bad anti-interference ability. However, variable structure controller has the disadvantages of chattering and big steady-state error. A new controller combines variable structure and PID control method for brushless DC motor (BLDCM) of magnetic suspended reaction flywheel (MSRW) is designed. It is based on analyzing of the MSRW system and modeling on BLDCM. The variable structure controller and the PID controller are combined to make a quite high precision speed controller. The simulation results prove that the new controller has the advantages of chattering and steady-state error reduction, system dynamic response improvement, invariance to the disturbances compared with the variable structure controller and the PID controller. Furthermore, this new controller has the features of simplicity of design and implement, which will be important for realizing the high precision and high stability satellite attitude control.

In this paper, some simulation results of 3D imaging of ground moving target are presented. Chirp stepped-frequency signal is transmitted in the interferometric inverse synthetic aperture radar system. Before the processing of 3D imaging, the strong ground clutter has been removed by using a new chirp stepped-frequency signal format. Then the 3D images of the ground moving targets can be achieved according to the principle of the interferometric 3D imaging.

Objectives To analyse the prevalence and risk factors of prehypertension among normal blood pressure diabetic patients. To assess the renal function of prehypertensive diabetic patients. To compare the cumulative incidence of hypertension between prehypertension and ideal blood pressure groups after 5 years followed up and analyse risk factors of it in prehypertensive diabetic patients. Methods A combination methods of retrospective and prospective analysis was applied to carried out the study. 3 481 type 2 diabetes with normal blood pressure were selected as the research object and devided into the ideal blood pressure and prehypertension groups according to th level of blood pressure. To analyse the prevalence, risk factors and renel damage of prehypertensive diabetic patients. These patients were followed up for five years and the cumulative incidence of hypertension were analyse. Risk factors for hypertension in prehypertensive diabetic patients were evaluated. Excel software was applied for databases and SPSS13.0 software was applied for statistical analysis. Results Among 3 481 normal blood pressure patients with diabetes, 943 patients (27.1%) belong to the ideal blood pressure group and 2 538 patients (72.9%) belong to prehypertension group. 2 855 cases (82.0%) were male and 626 cases (18.0%) were female. The range of their aged was from 22 to 91 years old and their average age was 57.4 ± 10.6 years old. Results of single factor analysis showed that prevalence of prehypertension in male and female patients was 74.2% vs 67.3%, in snoring and not snoring patients was 74.8% vs 70.0%, in the smoking and nonsmoking patients was 74.4% vs 69.9%. Their difference were significant (P 2 . Their difference were significant (P Conclusions Male, snoring, smoking, high levels of TG, LDL-C and BMI were risk factors of prehypertensive diabetic patients. Prehypertension was a risk factor of renal insufficiency. For diabetic patients. The 5-years cumulative incidence of hypertension in the prehypertensive diabetic patients was more higher than that in ideal blood pressure diabetic patients. Male and overweight were risk factors of 5-years cumulative incidence of hypertension in prehypertensive diabetic patients. We should further strengthen integrated control of risk factors in prehypertensive diabetic patients and improve the prognosis of patients by comprehensive prevention.