A numerical investigation is conducted on the flow past a transversely oscillating square cylinder at various amplitudes with Reynolds number of 200 in “lock-on” region. Floquet stability analysis was then applied to study three-dimensional instability its wake. The results show that mean recirculating region sizes decrease and force coefficients increase as amplitude increases. dynamic mode decomposition reveals although changes topology high order harmonic modes, primary modes share...

In this paper, an enhanced proportionate normalized least mean square (PNLMS) algorithm with the hybrid l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2,0</sub> -norm constraint is proposed for block-sparse signal processing. The penalizes a mixed on PNLMS to fully exploit sparsity and handle signals, which called norm constrained (L20-PNLMS). L20-PNLMS well derived carefully analyzed. Various experiments have been constructed verify...

Turbulent kinetic energy and turbulent dissipation are important aspects of the flow field characteristics, which can affect wear loss in mixing equipment. In order to increase equipment process, a series fractal impellers were designed based on iteration method, effects dimension number iterations characteristics investigated. Firstly, distribution its uniformity studied. Then, rate studied interpreted using vortex analysis, power device was further The results showed that: for field, an...

A robust sparse least-mean mixture-norm (LMMN) algorithm is proposed, and its performance appraised in the context of estimating a broadband multi-path wireless channel. The proposed implemented via integrating correntropy-induced metric (CIM) penalty into conventional LMMN to modify basic cost function, which denoted as CIM-based (CIM-LMMN) algorithm. CIM-LMMN derived detail within kernel framework. updating equation can provide zero attractor attract non-dominant channel coefficients...

The characteristics of the multiple filaments formed by prefocused and freely propagating femtosecond laser pulses are investigated compared. It is shown in our experiments that diameter, length, stability, interaction for two cases can be quite different. beam indicate dynamic spatial evolution with higher intensity electron density. They have a typical diameter 100 microm shorter length. In free propagation case, exhibit interesting properties such as hundred-meter distance mm-size...

In this paper, a sparse set-membership proportionate normalized least mean square (SM-PNLMS) algorithm integrated with correntropy induced metric (CIM) penalty is proposed for acoustic channel estimation and echo cancellation. The CIM used constructing new cost function within the kernel framework. penalized SM-PNLMS (CIMSM-PNLMS) derived analyzed in detail. A desired zero attraction term put forward updating equation of CIMSM-PNLMS to force inactive coefficients zero. performance...

This work uses the binary target region for synthetic aperture radar (SAR) automatic recognition (ATR). Due to differences of physical sizes and shapes, residuals among same classes those between different targets are distributed in manners. The Euclidean distance transform is then performed on further enhance such differences, which beneficial correctly discriminating targets. Based results, a similarity measure formed according distribution characteristics residuals. In addition, designed...

Abstract Vallisneria spinulosa Yan ( V.spinulosa Yan) with good ability of water purification is often used for ecological restoration polluted bodies. However, it difficult to survive in turbid bodies due the low lighting condition. This study explored feasibility introducing artificial underwater light source into high turbidity strengthen by Yan. Addition promoted clonal reproduction Yan, thus enhancing removal loads total nitrogen (TN), phosphorus (TP), and nitrate...

An improved norm-constrained set-membership normalized least mean square (INCSM-NLMS) algorithm is proposed for adaptive sparse channel estimation (ASCE). The INCSM-NLMS implemented by incorporating an <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:msub><mml:mrow><mml:mi>l</mml:mi></mml:mrow><mml:mrow><mml:mi>p</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math>-norm penalty into the cost function of traditional (SM-NLMS) algorithm, which also denoted as...

In this paper, an improved set-membership proportionate normalized least mean square (SM-PNLMS) algorithm is proposed for block-sparse systems. The algorithm, which named the SM-PNLMS (BS-SMPNLMS), implemented by inserting a penalty of mixed l 2 , 1 norm weight-taps into cost function SM-PNLMS. Furthermore, BS-SMPNLMS (the (BS-SMIPNLMS algorithm) also derived and analyzed. algorithms are well investigated in framework network echo cancellation. results simulations indicate that devised...

Sparse channel estimation has attracted more attention for various broadband wireless communication systems. Square error criterion based adaptive filter algorithms are extensively studied sparse estimations (SCE) such as zero-attracting (ZA) least mean square (ZA-LMS) and reweighting ZA-LMS (RZA-LMS) algorithms. However, these LMS usually sensitive to the scaling of their input signal. In this paper, an improved algorithm is proposed on basis normalized (NLMS) algorithm, reweighted ZA (RZA)...

For compensating the bias caused by noisy input which is always ignored ordinary algorithms, two novel algorithms with zero-attraction (ZA) penalties are proposed in this paper. The first one constructs a bias-compensated term updating recursion of proportionate normalized least mean square (PNLMS) algorithm named BC-ZA-PNLMS algorithm. second employs and correntropy induced metric (CIM) constraint to renew PNLMS BC-CIM-PNLMS Both these derived on basis unbiased criterion. Simulation...

Aiming at the defects of Genetic Algorithm (GA) for solving Maximum Clique Problem (MCP) in more complicated, long-running and poor generality, a fast genetic algorithm (FGA) is proposed this paper. A new chromosome repair method on degree, elitist selection based random repairing, uniform crossover inversion mutation are adopted algorithm. These components can speed up search effectively prevent from trapping into local optimum. The was tested DIMACS benchmark graphs. Experimental results...

Supercontinuum (SC) generation from laser filamentation in air is found to depend strongly on the pulse duration. Rainbow-like SC observed only for a of appropriate negative chirp that agrees with predictions put forward by Golubtsov et al. [Quantum Electron. 33 (2003) 525]. The conversion efficiency an 800-nm light rainbow-like be highest 257 fs pulses initial chirp. A larger will lead surviving at longer distance.

The harmony search (HS) algorithm is a recently developed meta-heuristic algorithm, this paper presents an improved diversified (IDHS) for solving continuous optimization problems. Limiting the number of identical harmonies stored in memory can increase diversity solutions. Pitch adjusting rate (PAR) one parameters HS. Starting with maximal PAR and ending minimal produce better results. A combination above two methods problems investigated paper. Simulation results IDHS are compared other HS...

We have demonstrated an order of magnitude increase in terahertz (THz) power, and showed that such enhancement might be attributed to formation asymmetric plasma profile which the density increases steeply head decreases gradually tail. solved a onedimensional model with without accounting for amplification THz wave. Comparison these two cases implies wave may been amplified during propagation plasma.

A sparsity-aware variable kernel width proportionate affine projection (AP) algorithm is devised for identifying sparse system in impulsive noise environments. For the algorithm, symmetry maximum correntropy criterion (MCC) employed to develop a new cost function improving PAP then and l p -norm-like constraint are incorporated into cost-function, which named as -norm (LP-VPAP) algorithm. The LP-VPAP investigated verified under interference Experimental results show that gets faster...