Dynamic image stabilization precision of an optical image-stable device is a key technical ***,a fast dynamic image stabilization precision test system for an optical image-stable device is developed.A large-aperture ...
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Dynamic image stabilization precision of an optical image-stable device is a key technical ***,a fast dynamic image stabilization precision test system for an optical image-stable device is developed.A large-aperture collimator with a designed cross divisional board is used to simulate the infinity *** image-stable device is installed on the motion simulator with six degrees of freedom which is used to simulate the moving state of the *** CCD camera installed behind the eyepiece lens of the image-stable device acquires images rapidly and in real *** local energy maxima center of the cross light spot can be acquired accurately through the proposed algorithm using the Hessian *** addition,to deal with the CCD non-uniformity,an adaptive non-uniformity correction algorithm based on bi-dimensional empirical mode decomposition is *** actual test results for the proposed method show that the test error of dynamic image stabilization is less than 0.7,and the time for the frame image acquisition and processing is less than 10 ms,which demonstrates the effectiveness of the test system.
The development of appropriate Electric Vehicle (EV) charging strategies has been identified as an effective way to accommodate an increasing number of EVs on Low Voltage (LV) distribution networks. Most research stud...
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ISBN:
(纸本)9781479925230
The development of appropriate Electric Vehicle (EV) charging strategies has been identified as an effective way to accommodate an increasing number of EVs on Low Voltage (LV) distribution networks. Most research studies to date assume that future charging facilities will be capable of regulating charge rates continuously, while very few papers consider the more realistic situation of EV chargers that support only on-off charging functionality. In this work, a distributed charging algorithm applicable to on-off based charging systems is presented. Then, a modified version of the algorithm is proposed to incorporate real power system constraints. Both algorithms are compared with uncontrolled and centralized charging strategies from the perspective of both utilities and customers.
The low-frequency periodic error of star tracker is one of the most critical problems for high-accuracy satellite attitude *** this paper an approach is proposed to identify and compensate the low-frequency periodic e...
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The low-frequency periodic error of star tracker is one of the most critical problems for high-accuracy satellite attitude *** this paper an approach is proposed to identify and compensate the low-frequency periodic error for star tracker in attitude *** analytical expression between the estimated gyro drift and the low-frequency periodic error of star tracker is derived *** then the low-frequency periodic error,which can be expressed by Fourier series,is identified by the frequency spectrum of the estimated gyro drift according to the solution of the first ***,the compensated model of the low-frequency periodic error is established based on the identified parameters to improve the attitude determination ***,promising simulated experimental results demonstrate the validity and effectiveness of the proposed *** periodic error for attitude determination is eliminated basically and the estimation precision is improved greatly.
An implementation of adaptive filtering, composed of an unsupervised adaptive filter (UAF), a multi-step forward linear predictor (FLP), and an unsupervised multi-step adaptive predictor (UMAP), is built for sup...
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An implementation of adaptive filtering, composed of an unsupervised adaptive filter (UAF), a multi-step forward linear predictor (FLP), and an unsupervised multi-step adaptive predictor (UMAP), is built for suppressing impulsive noise in unknown circumstances. This filtering scheme, called unsupervised robust adaptive filter (URAF), possesses a switching structure, which ensures the robustness against impulsive noise. The FLP is used to detect the possible impulsive noise added to the signal, if the signal is "impulse-free", the filter UAF can estimate the clean sig- nal. If there exists impulsive noise, the impulse corrupted samples are replaced by predicted ones from the FLP, and then the UMAP estimates the clean signal. Both the simulation and experimental results show that the URAF has a better rate of convergence than the most recent universal filter, and is effective to restrict large disturbance like impulsive noise when the universal filter fails.
In order to improve real-time performance of the fire controlsystem, a ballistic resolving method based on the improved particle swarm optimization (PSO) algorithm is proposed, which improves the response speed of th...
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In order to improve real-time performance of the fire controlsystem, a ballistic resolving method based on the improved particle swarm optimization (PSO) algorithm is proposed, which improves the response speed of the system and provides a convenient extension to parallel computing on multicore platforms. First, particles are generated and initialized around the pre-estimated aiming angle. Then each particle is evaluated by an objective function composed of the ballistic differential equation etc. Finally, the position and velocity of particle swarm are updated. In order to accelerate the convergence speed, the correction angle of the global best particle obtained by Zhou's iterative and correction formula is used to guide the update of particle swarm. Experimental results show that the calculation speed is twice that of the iterative and correction method, and the convergence speed of particle swarm is 1.5 times that of the conventional PSO algorithm. Moreover, the proposed method is fully compatible with parallel computing and can further shorten execution time on multicore platforms.
In order to enable the Web data to be applied in a non-Internet environment, overcoming the timeliness of Web data, this study proposes a domain Web data standardization organization method. The domain Web standardiza...
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This paper investigates distributed leader-following swarm stability of heterogeneous multi-agent systems with periodically intermittent control. We assume that the agents in the network are nonidentical and the coupl...
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ISBN:
(纸本)9789881563835
This paper investigates distributed leader-following swarm stability of heterogeneous multi-agent systems with periodically intermittent control. We assume that the agents in the network are nonidentical and the coupling matrix is balanced. Each heterogeneous follower is assumed to obtain some information from the leader and the neighbors only on a series of periodically time intervals. We show that the system will be exponentially stable. The stability properties are proved via theoretical analysis and verified via numerical simulations. The stability of the heterogeneous multi-agent systems is proved based on matrix theory and the Lyapunov stability theorem. A numerical example is shown to demonstrate the effectiveness of the theoretical result.
This paper investigates distributed leader-following swarm of heterogeneous multi-agent systems. Comparing with the existing works on leader-following swarm of homogeneous multi-agent systems, this paper is much more ...
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This paper investigates distributed leader-following swarm of heterogeneous multi-agent systems. Comparing with the existing works on leader-following swarm of homogeneous multi-agent systems, this paper is much more approaching the practical situation because the agents have different dynamics. We show that the heterogeneous followers will gather with a certain error lever under some assumptions and conditions. The stability properties have been proven by theoretical analysis and verified via numerical simulation. The stability of the heterogeneous multi-agent systems has been achieved based on matrix theory and the Lyapunov stability theorem. Numerical simulation is given to demonstrate the effectiveness of the theoretical result.
Vehicle yaw rates were measured by smartphone and high-precision inertial navigation system (INS). The influence of smartphone places on the measurement accuracy of yaw rate was analyzed. A self-adaptive weighted fusi...
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Vehicle yaw rates were measured by smartphone and high-precision inertial navigation system (INS). The influence of smartphone places on the measurement accuracy of yaw rate was analyzed. A self-adaptive weighted fusion algorithm was applied to reduce the measurement error of built-in gyroscope and orientation sensor of smartphone. The extreme value theory of multivariable function was used to obtain the optimal weighting factors of two sensors. The best value of yaw rate was calculated by weighted summation. Analysis result indicates that the impact of smartphone position on the measurement accuracy is very small. When smartphone is not fixed at center of gravity, the maximal relative errors of yaw rates measured by two sensors of smartphone are 0.7397% and 0.9238%, respectively. Average absolute error between fused data and INS data is 0.6077(°)·s-1. Compared with the data measured by two sensors of smartphone, the average absolute error reduces by 34.3% and 50.0%, respectively. The variance of fused data declines and rapidly converges as the number of measurement increases. The convergent time is about 6 s.
This paper proposes the concept of pinning noise and then investigates the phenomenon of stochastic resonance of coupled complexsystems driven by pinning noise, where the noise has an α-stable distribution. Two kind...
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This paper proposes the concept of pinning noise and then investigates the phenomenon of stochastic resonance of coupled complexsystems driven by pinning noise, where the noise has an α-stable distribution. Two kinds of pinning noise are taken into account: partial noise and switching noise. In particular, we establish a connection between switching noise and global noise when Gaussian noise is considered. It is shown that switching noise can not only achieve a stronger resonance effect, but it is also more robust to induce the resonance effect than partial noise.
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