期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
Blind recognition of k/n rate convolutional encoders from noisy observation 被引量:14
1
作者 Li Huang Wengu Chen +1 位作者 Enhong Chen Hong Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期235-243,共9页
Blind recognition of convolutional codes is not only essential for cognitive radio, but also for non-cooperative context. This paper is dedicated to the blind identification of rate k/n convolutional encoders in a noi... Blind recognition of convolutional codes is not only essential for cognitive radio, but also for non-cooperative context. This paper is dedicated to the blind identification of rate k/n convolutional encoders in a noisy context based on Walsh-Hadamard transformation and block matrix (WHT-BM). The proposed algorithm constructs a system of noisy linear equations and utilizes all its coefficients to recover parity check matrix. It is able to make use of fault-tolerant feature of WHT, thus providing more accurate results and achieving better error performance in high raw bit error rate (BER) regions. Moreover, it is more computationally efficient with the use of the block matrix (BM) method. © 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 Cognitive radio CONVOLUTION Convolutional codes Error correction Hadamard matrices Hadamard transforms Linear transformations mathematical transformations Matrix algebra Signal encoding
在线阅读 下载PDF
Distributed tracking control of unmanned aerial vehicles under wind disturbance and model uncertainty 被引量:3
2
作者 Kun Zhang Xiaoguang Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第6期1262-1271,共10页
A distributed robust method is developed for cooperative tracking control of unmanned aerial vehicles under unknown wind disturbance and model uncertainty. The communication network among vehicles is a directed graph ... A distributed robust method is developed for cooperative tracking control of unmanned aerial vehicles under unknown wind disturbance and model uncertainty. The communication network among vehicles is a directed graph with switching topology. Each vehicle can only share its states with its neighbors. Dynamics of the vehicles are nonlinear and affected by the wind disturbance and model uncertainty. Feedback linearization is adopted to transform the dynamics of vehicles into linear systems. To account for the wind disturbance and model uncertainty, a robust controller is designed for each vehicle such that all vehicles ultimately synchronize to the virtual leader in the three-dimensional path. It is theoretically shown that the position states of the vehicles will converge to that of the virtual leader if the communication network has a directed spanning tree rooted at the virtual leader. Furthermore, the robust controller is extended to address the formation control problem. Simulation examples are also given to illustrate the effectiveness of the proposed method. © 2016 Beijing Institute of Aerospace Information. 展开更多
关键词 Aircraft control Controllers Directed graphs Feedback linearization Linear systems mathematical transformations NAVIGATION TOPOLOGY Uncertainty analysis Unmanned aerial vehicles (UAV) VEHICLES
在线阅读 下载PDF
Near field 3-D imaging approach for joint high-resolution imaging and phase error correction 被引量:2
3
作者 Yang Fang Baoping Wang +2 位作者 Chao Sun Zuxun Song Shuzhen Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期199-211,共13页
This paper combines compressed sensing (CS) imaging theory and range migration algorithm (RMA), and then proposes a near-field three-dimensional (3-D) imaging approach for joint high-resolution imaging and phase error... This paper combines compressed sensing (CS) imaging theory and range migration algorithm (RMA), and then proposes a near-field three-dimensional (3-D) imaging approach for joint high-resolution imaging and phase error correction. Firstly, a sparse measurement matrix construction method based on a logistic sequence is proposed, which conducts nonlinear transformation for the determined logistic sequence, making it obey uniform distribution, then conducts sign function mapping, and generates the pseudorandom sequence with Bernoulli distribution, thus leading to good signal recovery under down-sampling and easy availability for engineering realization. Secondly, in combination with the RMA imaging approach, the dictionary with all scene information and phase error correction is constructed for CS signal recovery and error correction. Finally, the non-quadratic solution model jointing imaging and phase error correction based on regularization is built, and it is solved by two steps - the separable surrogate functionals (SSF) iterative shrinkage algorithm is adopted to realize target scattering estimate; the iteration mode is adopted for the correction of the dictionary model, so as to achieve the goal of error correction and highly-focused imaging. The proposed approach proves to be effective through numerical simulation and real measurement in anechoic chamber. The results show that, the proposed approach can realize high-resolution imaging in the case of less data; the designed measurement matrix has better non-coherence and easy availability for engineering realization. The proposed approach can effectively correct the phase error, and achieve highly-focused target image. © 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 Compressed sensing Error correction Image reconstruction Iterative methods Linear transformations mathematical transformations Signal reconstruction Signal sampling
在线阅读 下载PDF
An Algorithm for Ship Wake Detection from the SAR Images Using the Radon Transform and Morphological Image Processing 被引量:2
4
作者 金亚秋 王世庆 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第4期7-12,共6页
Using the Radon transform and morphological image processing, an algorithm for ship's wake detection in the SAR (synthetic aperture radar) image is developed. Being manipulated in the Radon space to invert the gra... Using the Radon transform and morphological image processing, an algorithm for ship's wake detection in the SAR (synthetic aperture radar) image is developed. Being manipulated in the Radon space to invert the gray-level and binary images, the linear texture of ship wake in oceanic clutter can be well detected. It has been applied to the automatic detection of a moving ship from the SEASAT SAR image. The results show that this algorithm is well robust in a strong noisy background and is not very sensitive to the threshold parameter and the working window size. 展开更多
关键词 ALGORITHMS Image processing mathematical transformations Radar clutter Radar target recognition Spurious signal noise Synthetic aperture radar
在线阅读 下载PDF
Evolutionary Programming for IP/MIP Problems with Linear Constraints 被引量:2
5
作者 Ren, Qingsheng Zeng, Jin Qi, Feihu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第3期59-64,共6页
In this paper, we propose a modified evolutionary programming with dynamic domain for solving nonlinear IP/MIP problems with linear constraints, without involving penalty function or any transformation for the problem... In this paper, we propose a modified evolutionary programming with dynamic domain for solving nonlinear IP/MIP problems with linear constraints, without involving penalty function or any transformation for the problem to a linear model or others. The numerical results show that the new algorithm gives a satisfactory performance in which it works of high speed, and accuracy in IP/MIP problems. 展开更多
关键词 ALGORITHMS Constraint theory mathematical models mathematical transformations Problem solving
在线阅读 下载PDF
Some Equivalence Transform Methods for Simulating Models in Control Systems
6
作者 Degui, Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第4期32-42,共11页
In this paper two classes of equivalence transform methods for solving ordinary differential equations are proposed. One class of method is the equivalence integral transform method for special differential algebraic ... In this paper two classes of equivalence transform methods for solving ordinary differential equations are proposed. One class of method is the equivalence integral transform method for special differential algebraic problems. The advantage of this class of method is such that the amount of work calculating one integration with parameters becomes that of two interpolations, when the system of nonlinear equations is solved on the right hand side function. The other class of method is the equivalence substitution method for avoiding calculating derivative on the right hand side function. In order to avoid calculation derivatives, two equivalence substitution methods are proposed here. The application instances of some special effect of the equivalence substitution methods are given. 展开更多
关键词 ALGEBRA Calculations Computer simulation Control systems Differential equations Integration Interpolation mathematical models mathematical transformations Nonlinear equations Numerical methods
在线阅读 下载PDF
Yes, Science is Confronted by a Great Revolution
7
作者 Smulsky, Jozeph J. 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第2期72-76,共5页
An equation is derived to explain the General Theory of Relativity and the effects of GTR: the rotations of planets' perihilion, deflects of star light by a gravitational mass, and the existence of gravitational w... An equation is derived to explain the General Theory of Relativity and the effects of GTR: the rotations of planets' perihilion, deflects of star light by a gravitational mass, and the existence of gravitational waves. Differentiation was used in the derivation but without the dependence of mass, space and time on velocity. The general postulates that are the bases of the new approach to electrodynamics were stated. 展开更多
关键词 Charged particles Differentiation (calculus) Electromagnetic field effects Electromagnetic waves Equations of motion Error analysis Errors GRAVITATION mathematical models mathematical transformations Velocity
在线阅读 下载PDF
Decision Making as Theorem Proving
8
作者 Zhu, Mingyuan Wang, Chengwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第1期3-32,共30页
We present a method for using type theory to solve decision making problem. Our method is based on the view that decision making is a special kind of theorem proving activity. An isomorphism between problems and types... We present a method for using type theory to solve decision making problem. Our method is based on the view that decision making is a special kind of theorem proving activity. An isomorphism between problems and types, and solutions and programs has been established to support this view which is much similar to the Curry-Howard isomorphism between propositions and types, and proofs and programs. To support our method, a proof development system called PowerEpsilon has been developed, and the synthesis of a decision procedure for validity of first-order propositional logic is discussed to show the power of the system. 展开更多
关键词 Computer programming languages Computer software Decision theory Formal logic mathematical transformations Recursive functions Theorem proving
在线阅读 下载PDF
Conversion Technique of Vector Wave Functions:Formulas and Applications
9
作者 Xu, Penggen Lu, Shu Xu, Ying 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1997年第3期6-15,共10页
The conversion theory of vector wave function is one of important problems in electromagnetic. This paper presents a systematic treatment of the conversion technique and some applications. In this paper, the conversio... The conversion theory of vector wave function is one of important problems in electromagnetic. This paper presents a systematic treatment of the conversion technique and some applications. In this paper, the conversion relations of standard and non-standard spherical vector wave functions, standard and non-standard cylindrical vector wave functions, and spherical and cylindrical vector wave functions are developed. As an example of application of vector wave function expansion, the expansion of plane wave and dipole field in two-medium half-spaces are given. As an example of application of vector wave function conversion, the scattering patterns of buried conducting and dielectric spheres are presented. Inspection on the numerical results shows that the technique and associated programs presented in this paper are efficient. 展开更多
关键词 Boundary conditions Boundary value problems Dielectric devices Electromagnetic wave scattering mathematical transformations VECTORS
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部