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.
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.
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.
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.
Solving the optimal control problem with a free final time, such as suborbital launch vehicle (SLV) trajectory optimization with two control variables and multi-constraints ones based on particle swarm optimization (P...
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Solving the optimal control problem with a free final time, such as suborbital launch vehicle (SLV) trajectory optimization with two control variables and multi-constraints ones based on particle swarm optimization (PSO), the smoothness of control variable can not be satisfied by linear interpolation method. A novel method including some improving strategies based on PSO for trajectory optimization is proposed, named LCPSO which is a kind of Cooperate PSO based on Legendre orthogonal polynomials. An additional control variable is introduced and transcribes the original optimal problem to a problem with fixed final time, and one dimension searching method based on interval analysis is used to optimize the additional control variable. Furthermore, a theorem on how to find the boundaries of the coefficient of polynomials is proved. Compared with basic PSO, LCPSO has traits of lower dimensions and smoother control variable. An example of trajectory optimization shows the effectiveness of the LCPSO algorithm.
Common algorithmic problem is an optimization problem, which has the nice property that several other NP-complete problems can be reduced to it in linear time. A tissue P system with cell division is a computing model...
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Common algorithmic problem is an optimization problem, which has the nice property that several other NP-complete problems can be reduced to it in linear time. A tissue P system with cell division is a computing model which has two basic characters: intercellular communication and the ability of cell division. The ability of cell division allows us to obtain an exponential amount of cells in linear time and to design cellular solutions to computationally hard problems in polynomial time. We here present an effective solution to the common algorithmic decision problem using a family of recognizer tissue P systems with cell division.
In this paper, we formulate and investigate a memristor-based switching network which is directly extended from Itoh and Chua's chaotic circuit. Conditions are derived which ensure the existence of an equilibrium ...
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ISBN:
(纸本)9781424494408
In this paper, we formulate and investigate a memristor-based switching network which is directly extended from Itoh and Chua's chaotic circuit. Conditions are derived which ensure the existence of an equilibrium point and the uniformly stable for state trajectories of the memristor-based switching network. The analysis in the paper employs results from the theory of differential equations with discontinuous right-hand side as introduced by Filippov. It is believed that the criteria in this paper is also valuable in the design of memristor-based switching network which can be used to solve efficiently classes of optimization problems arising in practical engineering applications.
Speckle is a granular noise that inherently exists in all types of coherent imaging systems. This paper presents a quantitative study on five despeckling methods such as frost filter, kuan filter, speckle reducing an ...
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Speckle is a granular noise that inherently exists in all types of coherent imaging systems. This paper presents a quantitative study on five despeckling methods such as frost filter, kuan filter, speckle reducing an isotropic diffusion, homomorphic filter and wavelet filter. We select six objective evaluation parameters, such as signal-to-ratio, contrast signal-to-noise ratio, figure of merit, least absolute error, edge protection factor, signal-to-minimum mean square error ratio, to quantify the performance of these filters. The comparative study will provide some parameter comparative reference for selecting a suitable filter in the ultrasound image processing.
Heart rate (HR) signal analysis is widely used in the medicine and medical research area. Physical activities (PA) are commonly recognized to greatly affect the changes of heart rate. A method of Evolutionary Neural N...
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Heart rate (HR) signal analysis is widely used in the medicine and medical research area. Physical activities (PA) are commonly recognized to greatly affect the changes of heart rate. A method of Evolutionary Neural Network - Neuro-evolution of Augmenting Topologies (NEAT) is used to build a PA-based HR predictor model. Through special coding, crossover and mutation operator, NEAT can implement network topology and connectivity weights evolution simultaneously. The common problem in evolutionary neural network, like competing conventions, how to protect the new innovation are effectively solved. The experimental results demonstrated the application potential of the approach.
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