1,912 research outputs found

    Low Cost Swarm Based Diligent Cargo Transit System

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    The goal of this paper is to present the design and development of a low cost cargo transit system which can be adapted in developing countries like India where there is abundant and cheap human labour which makes the process of automation in any industry a challenge to innovators. The need of the hour is an automation system that can diligently transfer cargo from one place to another and minimize human intervention in the cargo transit industry. Therefore, a solution is being proposed which could effectively bring down human labour and the resources needed to implement them. The reduction in human labour and resources is achieved by the use of low cost components and very limited modification of the surroundings and the existing vehicles themselves. The operation of the cargo transit system has been verified and the relevant results are presented. An economical and robust cargo transit system is designed and implemented.Comment: 6 pages, 9 figures, 1 block diagra

    Novel spectral kurtosis technology for adaptive vibration condition monitoring of multi-stage gearboxes

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    In this paper, the novel wavelet spectral kurtosis (WSK) technique is applied for the early diagnosis of gear tooth faults. Two variants of the wavelet spectral kurtosis technique, called variable resolution WSK and constant resolution WSK, are considered for the diagnosis of pitting gear faults. The gear residual signal, obtained by filtering the gear mesh frequencies, is used as the input to the SK algorithm. The advantages of using the wavelet-based SK techniques when compared to classical Fourier transform (FT)-based SK is confirmed by estimating the toothwise Fisher's criterion of diagnostic features. The final diagnosis decision is made by a three-stage decision-making technique based on the weighted majority rule. The probability of the correct diagnosis is estimated for each SK technique for comparison. An experimental study is presented in detail to test the performance of the wavelet spectral kurtosis techniques and the decision-making technique

    Invariant chiral differential operators and the W_3 algebra

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    Attached to a vector space V is a vertex algebra S(V) known as the beta-gamma system or algebra of chiral differential operators on V. It is analogous to the Weyl algebra D(V), and is related to D(V) via the Zhu functor. If G is a connected Lie group with Lie algebra g, and V is a linear G-representation, there is an action of the corresponding affine algebra on S(V). The invariant space S(V)^{g[t]} is a commutant subalgebra of S(V), and plays the role of the classical invariant ring D(V)^G. When G is an abelian Lie group acting diagonally on V, we find a finite set of generators for S(V)^{g[t]}, and show that S(V)^{g[t]} is a simple vertex algebra and a member of a Howe pair. The Zamolodchikov W_3 algebra with c=-2 plays a fundamental role in the structure of S(V)^{g[t]}.Comment: a few typos corrected, final versio

    Existence and optimal regularity theory for weak solutions of free transmission problems of quasilinear type via Leray-Lions method

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    We study existence and regularity of weak solutions for the following PDE -\dive(A(x,u)|\nabla u|^{p-2}\nabla u) = f(x,u),\;\;\mbox{in $B_1$}. where A(x,s)=A+(x)χ{s>0}+A−(x)χ{s≤0}A(x,s) = A_+(x)\chi_{\{s>0\}}+A_-(x)\chi_{\{s\le 0\}} and f(x,s)=f+(x)χ{s>0}+f−(x)χ{s≤0}f(x,s) = f_+(x)\chi_{\{s>0\}}+f_-(x)\chi_{\{s\le 0\}}. Under the ellipticity assumption that 1μ≤A±≤μ\frac{1}{\mu}\le A_{\pm} \le \mu, A_{\pm}\in C(\O) and f_{\pm}\in L^N(\O), we prove that under appropriate conditions the PDE above admits a weak solution in W1,p(B1)W^{1,p}(B_1) which is also Cloc0,αC^{0,\alpha}_{loc} for every α∈(0,1)\alpha\in (0,1) with precise estimates. Our methods relies on similar techniques as those developed by Caffarelli to treat viscosity solutions for fully non-linear PDEs (c.f. \cite{C89}). Other key ingredients in our proofs are the \TT_{a,b} operator (which was introduced in \cite{MS22}) and Leray-Lions method (c.f. \cite{BM92}, \cite{MT03})
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