Finding a fixed point to nonexpansive operator, i.e., $x^*=Tx^*$, abstracts many problems in numerical linear algebra, optimization, and other areas of scientific computing. To solve fixed-point problems, we propose ARock, an algorithmic framework which multiple agents (machines, processors, or cores) update $x$ asynchronous parallel fashion. Asynchrony is crucial computing since it reduces synchronization wait, relaxes communication bottleneck, thus speeds up significantly. At each step...

This paper proposes parallel and distributed algorithms for solving very large-scale sparse optimization problems on computer clusters clouds. Modern datasets usually have a large number of features or training samples, they are stored in manner. Motivated by the need with datasets, we propose two approaches including (i) implementations prox-linear (ii) GRock, greedy block coordinate descent method. Different separability properties objective terms problem enable different data schemes...

This paper focuses on coordinate update methods, which are useful for solving problems involving large or high-dimensional datasets.They decompose a problem into simple subproblems, where each updates one, small block of, variables while fixing others.These methods can deal with linear and nonlinear mappings, smooth nonsmooth functions, as well convex nonconvex problems.In addition, they easy to parallelize.The great performance of depends subproblems.To derive subproblems several new...

Although atmospheric pressure dielectric barrier discharges (DBDs) have a long history, the effects of water vapor on discharge morphology and kinetics not been studied intensively. We report simultaneous investigation morphology, OH H2O2 production in Ar He DBDs operated at different concentrations powers. The combined study allows us to assess impact power concentration dependence production. is investigated by ICCD images current–voltage waveforms. These diagnostics are complemented...

The relationship between the stability of tool materials and their cutting performance is a critical technical challenge for manufacturing industry, which essential selecting appropriate treatment processes to achieve superior performance. In this paper, standard experiment was used study sharpness knife with different residual austenite content. edges were characterized by an optical microscope (OM), scanning electron (SEM), back scattering diffraction (EBSD), transmission (TEM), analyze...

Cutting-edge wear is inevitable in the cutting process of knife. Studying relationship between performance knife and cutting-edge conducive to optimizing design increasing its service life. The micro-morphology edge during was systematically characterized by optical microscopy (OM) scanning electron (SEM). strength material matrix nanoindentation, microstructure X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), transmission (TEM). influence different microstructures geometry...

This paper studies the convergence of adaptively iterative thresholding (AIT) algorithm for compressed sensing. We first introduce a generalized restricted isometry property (gRIP). Then, we prove that AIT converges to original sparse solution at linear rate under certain gRIP condition in noise free case. While noisy case, its is also until attaining error bound. Moreover, as by-products, provide some sufficient conditions based on two well-known properties, i.e., coherence and (RIP),...

This paper introduces a parallel and distributed extension to the alternating direction method of multipliers (ADMM) for solving convex problem: minimize $\sum_{i=1}^N f_i(x_i)$ subject A_i x_i=c, x_i\in \mathcal{X}_i$. The algorithm decomposes original problem into N smaller subproblems solves them in at each iteration. Jacobian-type is well suited computing particularly attractive certain large-scale problems. few novel results. Firstly, it shows that extending ADMM straightforwardly from...

A highly sensitive, calibration-free method, wavelength modulation - direct absorption spectroscopy (WM-DAS), is proposed by extracting the characteristic frequencies of modulated laser intensity. This method combines advantages measuring absolute absorbance profile from DAS with enhanced noise rejection and high sensitivity WMS. The preliminary validation experiment H2O transitions shows that WM-DAS improves accuracy measurement a best-fit standard residual 4.9 × 10-5. new might inspire...

A novel method with high accuracy and easy implementation was proposed based on the sinewave-scanned direct absorption spectroscopy (DAS) in this paper. fitting routine time domain developed to simultaneously deduce baseline more importantly, absorbance through explicit expression offered by sinewave scan. This effectively solves difficulties of determination provides accurate wavelength calibration compared conventional DAS. The performance narrow scans frequency were experimentally...

The absorbance is of great importance in the tunable diode laser absorption spectroscopy (TDLAS) as it contains information both gas properties and spectroscopic parameters. A novel, calibration-free wavelength modulation-direct (WM-DAS) proposed experimentally verified this two-part paper. This method combines capability measurement from DAS advantages enhanced noise rejection high sensitivity WMS. In Part I, we focus on full theoretical basis procedures following three aspects:...