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Learning object detection models from weakly labeled data is an important topic in computer vision. Among various types of weak annotations, image-level object labeling is a natural one that tells the existence, but not the precise locations, of object instances in images. Learning object detectors from image-level labels can be naturally cast as a multiple instance learning (MIL) problem. Existing...
Ultrasonic examination is a routine inspection technology. It has several merits, such as no harm to human body, cheap and relative high precision inspection. So it is widely used in physical examination and various types of organ inspections. In order to increase the detection rate of liver disease in ultrasound images, a method extracting the liver region from ultrasound images is proposed in this...
Image fusion in remote sensing is an issue to fuse the texture information of panchromatic (PAN) channel and the spectral information of multispectral (MS) channels with lower spatial resolution (LR). In this paper, a method named SPCA is proposed to deal with image fusion from the perspective of sparse representation and PCA, in which the correlations both within and between channels are effectively...
In this paper, a method for lighting directions estimation of the uniform texture images has been proposed. The proposed algorithm does not require training database, and only utilizes one input image for estimating the lighting directions. By detecting the largest direction of the brightness changes of the input image, the azimuth angle of the light source can be estimated. The slant angle is estimated...
A new design method of guidance and control system for the submarine-to-air missile based on optimal theory is presented in this paper. Firstly, the small perturbation linearized state space models of pitch channel for both torpedo underwater mechanics and missile flight mechanics are established. Then the guidance and control system is designed by linear quadratic (LQ) soft terminal controller and...
In order to solve the control problem of parallel inverters for large-capacity motor drive system, a controlling means is studied which can change the instantaneous reference voltage of parallel inverters. Based on the equivalent circuit models and the control principles of the motor current and circulating current, the master-slave control system of changing the instantaneous reference voltage of...
The transport of an elliptic sheet electron beam with uniform density in uniform magnetic field is investigated by making use of a macroscopic cold-fluid model. General envelope equations and beam twisted angles are derived. In particular, the tilt of the elliptic sheet beam was numerically calculated by an example of W-band sheet beam klystron.
In this paper, the ponderomotive focusing forces are derived for a sheet electron beam in both periodic cusped magnetic and wiggler magnetic field configurations, which has a large aspect ratio, using two-time scale analytical method.
By using daily data of India market, an effort has been made to investigate the possible volatility and price-discovery relationships between the NIFTY spot index and index futures market with techniques of ARCH/GARCH model, Johansen's Cointegration test and Granger Causality test. The main conclusions of this paper are as follows: firstly, the introduction of stock index future (SIF) helps reduce...
The diocotron instability of a relativistic sheet electron beam propagating through a uniform magnetic field is studied using a macroscopic cold fluid model. The general eigenvalue equation is obtained for low-frequency perturbations. In the limit of a long axial wavelength, a dispersion relation is derived for the special case of a sharp boundary density profile and used to study stability properties...
Absorbing exchange rate as exogenous disturbance, a mixed GARCH-jump model is proposed to compare return series fluctuation of Shanghai composite index with that of Dow Johns Index. It also incorporates properties of asymmetry, clustering, leptokurtosis and fat-tail of index series fluctuation into an integrated analytic frame of so-called diffusion-jump. Fitness test of GARCH-jump model proves that...
In order to measure the open-ended fund's liquidity risk accurately, the method of non-liquidity and VaR are used in this paper. We measure the liquidity risk of open-ended fund with non-liquidity indicators, fitting these non-liquidity indicators of sample funds with GARCH model under normal distribution, t-distribution and generalized error distribution (GED), then put the fitting parameters into...
Both finite volume method and finite difference method are adopted to disperse 1-D unsteady flow and sediment equations, for establishing 1-D dam-break flow and sediment numerical model. Based on the sediment data of Xinji reservoir of different operating years, the flood after dam-break is simulated by using this model. Compared with dam break results of initial impoundment period, it shows the influence...
The thermal pollution due to the cooling water project of the phase IV expansion project of Yangluo power plant is studied using a 2-D horizontal mathematical model, to predict the flow and temperature fields of the warm water outflow from the power plant. Based on the calculated area of thermal pollution of this cooling water project, proposals to reduce the influences of the thermal pollution of...
The mathematical models of five-phase permanent magnet synchronous motor (PMSM) in abc frame and alphabeta frame are established, and the relationships between the torque and fundamental components, loss and harmonic components are revealed. To suppress the high third harmonic current appeared in five-phase machine especially, a novel space vector pulse width modulation (SVPWM) method which has a...
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