The analytical algorithm of program quaternion is studied,aiming at the problem of the arbitrary spacecraft attitude-adjusting *** also provides the analytical constructor method of the program quaternion for any give...
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The analytical algorithm of program quaternion is studied,aiming at the problem of the arbitrary spacecraft attitude-adjusting *** also provides the analytical constructor method of the program quaternion for any given initial quaternion and angle velocity,terminal quaternion and angle *** advantages of this method are as follows:(1)Good *** of the initial and terminal conditions are arbitrary;(2)Simple *** calculation process only involves the simple algebraic operation;(3)Easy to *** using the program quaternion model,the time consumption in the process of spacecraft attitude adjustment and the maximum angular velocity can be optimized *** to the Mathematical simulation results,the program quaternion tracking can be realized by a simple PD control law.
The general macroscopic examination of semen evaluation includes sperm density, concentration, motility and morphology. Among these general evaluations, the morphology assessment is widely considered to be one of the ...
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The general macroscopic examination of semen evaluation includes sperm density, concentration, motility and morphology. Among these general evaluations, the morphology assessment is widely considered to be one of the most important evaluations of male sperm characteristics. With the use of computer-assisted sperm analysis (CASA) techniques, more objective, accurate and precise outcomes of sperm morphology assessment can be obtained, comparing to manual methodology. In this article we will make a brief introduction to the common CASA techniques, commercial products and future work.
This paper proposed the a compressed sensing (CS)technique to ultrasound imaging and address the feasibility of compressive sensing theory for RF signal reconstruction in B-model medical ultrasound. with partial Fouri...
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This paper proposed the a compressed sensing (CS)technique to ultrasound imaging and address the feasibility of compressive sensing theory for RF signal reconstruction in B-model medical ultrasound. with partial Fourier sampling, we compare different reconstruction algorithm to the simulation RF signal. reconstruction from 50% of the samples of original numerical cyst phantom show temperate information loss and feasibility of application CS in medical ultrasound.
In this paper, a nonlinear chaotic system is presented, which is derived from the chua's circuit with a memristor. This is a four-dimensional autonomous circuit which exhibits chaotic behavior. The chaotic system ...
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ISBN:
(纸本)9781424494408
In this paper, a nonlinear chaotic system is presented, which is derived from the chua's circuit with a memristor. This is a four-dimensional autonomous circuit which exhibits chaotic behavior. The chaotic system is demonstrated by Lyapunov exponent, and phase portraits. Furthermore, this system can be stabilized by a switched feedback controller which can be obtained by solving a set of LMIs. And the results will be demonstrated by the numerical simulation.
An Echo state Network (ESN) based predictive control method for aircraft system is proposed to increase the flight quality. Aero craft is a nonlinear and time-varying system and its controllers are usually designed by...
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An Echo state Network (ESN) based predictive control method for aircraft system is proposed to increase the flight quality. Aero craft is a nonlinear and time-varying system and its controllers are usually designed by trajectory linearization method. Furthermore, the predictive controller is designed to adjust the current controlled variables by the trend of output to improve the quick responsiveness and traceability. Then, the stability of the system is proved by Lyapunov function. Finally, the numerical simulation results of step-response and attitude tracking illustrate the robustness and effect of the method.
Abstract Joint flexibility is an important factor to consider in the robot control design if high performance is expected for the robot manipulators. In this paper, we propose an adaptive tracking control method which...
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Abstract Joint flexibility is an important factor to consider in the robot control design if high performance is expected for the robot manipulators. In this paper, we propose an adaptive tracking control method which can deal with the kinematics uncertainty and uncertainties in both link and actuator dynamics of the rigid-link flexible-joint (RLFJ) robot system. Adaptive observers are designed to avoid acceleration measurements due to the fourth-order overall system dynamics. Convergence of both end-effector tracking errors and observing errors are proven and sufficient conditions are presented to guarantee system's asymptotic stability.
The potential use of molecular computation in attacking the Data Encryption Standard (DES) is already known, but the used computing models are not autonomous and require many tedious laboratory steps to execute. In th...
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The potential use of molecular computation in attacking the Data Encryption Standard (DES) is already known, but the used computing models are not autonomous and require many tedious laboratory steps to execute. In this paper, a description of attacking DES using tile self assembly models in Θ(1) distinct tile types is given theoretically. The computation takes advantage of tiles' autonomy and the characteristic of highly distributed parallel computation. Each assembly configuration yields the ciphertext in linear time with respect to the times of the round function included in DES. The feasibility of finding the main key of DES in tile assembly models has been discussed. Analysis indicates that the tile assembly models might succeed by using a little of DNA under low error rate.
Auto-Disturbance Rejection controller (ADRC) has been proved to be a capable replacement of PID with unmistakable advantage in performance and practicality. But it is difficult to obtain a set of optimal parameters, f...
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Auto-Disturbance Rejection controller (ADRC) has been proved to be a capable replacement of PID with unmistakable advantage in performance and practicality. But it is difficult to obtain a set of optimal parameters, for ADRC controller has too many parameters and has no deterministic rules to compute the parameters. In this paper, Objective function is constructed based on the control system performance indexes. Combined with experienced parameters of ADRC, an invasive weed optimization algorithm (IWO) is employed to obtain a set of key parameters. The simulation results show the validity of the IWO algorithm.
Polarity shifting has been a challenge to automatic sentiment classification. In this paper, we create a corpus which consists of polarity-shifted sentences in various kinds of product reviews. In the corpus, both the...
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Polarity shifting has been a challenge to automatic sentiment classification. In this paper, we create a corpus which consists of polarity-shifted sentences in various kinds of product reviews. In the corpus, both the sentimental words and shifting trigger words are annotated. Furthermore, we analyze all the polarity shifted sentences and categorize them into five categories: opinion-itself, holder, target, time and hypothesis. Experimental study shows the agreement of annotation and the distribution of the five categories of polarity shifting.
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