837 research outputs found

    Optimization for efficient structure-control systems

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    The efficiency of a structure-control system is a nondimensional parameter which indicates the fraction of the total control power expended usefully in controlling a finite-dimensional system. The balance of control power is wasted on the truncated dynamics serving no useful purpose towards the control objectives. Recently, it has been demonstrated that the concept of efficiency can be used to address a number of control issues encountered in the control of dynamic systems such as the spillover effects, selection of a good input configuration and obtaining reduced order control models. Reference (1) introduced the concept and presented analyses of several Linear Quadratic Regulator designs on the basis of their efficiencies. Encouraged by the results of Ref. (1), Ref. (2) introduces an efficiency modal analysis of a structure-control system which gives an internal characterization of the controller design and establishes the link between the control design and the initial disturbances to affect efficient structure-control system designs. The efficiency modal analysis leads to identification of principal controller directions (or controller modes) distinct from the structural natural modes. Thus ultimately, many issues of the structure-control system revolve around the idea of insuring compatibility of the structural modes and the controller modes with each other, the better the match the higher the efficiency. A key feature in controlling a reduced order model of a high dimensional (or infinity-dimensional distributed parameter system) structural dynamic system must be to achieve high efficiency of the control system while satisfying the control objectives and/or constraints. Formally, this can be achieved by designing the control system and structural parameters simultaneously within an optimization framework. The subject of this paper is to present such a design procedure

    Super-activation of quantum non-locality

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    In this paper we show that quantum non-locality can be super-activated. That is, one can obtain violations of Bell inequalities by tensorizing a local state with itself. Moreover, previous results suggest that such Bell violations can be very large.Comment: v2: Refs added. Same results, v3: Minor corrections. Close to the published versio

    Contradicted Natural Drugs in Some Specific Conditions: An Ayurveda Review

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    The safety of drugs is considered as one of the prime aspects of medical practice and use of safe is very important to avoid any chances of undesirable side effects. Ayurveda the alternative science of health management described use of various natural drugs for the treatment of different diseases. The safety of ayurveda medicine is also very important therefore it is very important to understand the concept of “drugs interactions” and “contradiction” with respect to natural medicine. The drug interaction can produces harmful effect while use of inappropriate medicine in specific conditions can causes undesired effects. Thus it is very important to acquire knowledge about the possible adverse effect of natural drugs due to the “drugs interactions” and “contradiction”. Considering these all facts present article explored concepts of “drugs interactions” and “contradiction” associated with Ayurveda drugs. Keywords: Ayurveda, Drug Interactions, Contradiction, Viruddha, Ahita and Prakritiviruddh

    Ayurveda Internal Medicine for the Management of Common Metabolic Disorders W.S.R. to Madhumeha and Sthoulya

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    The metabolic disorders are major health issues of today’s scenario and incidences of metabolic diseases increases day by day due to the disturbed pattern of life style. Ayurveda texts have described term “Santarpanjanya Vikaras” which resembles diseases of defective tissue metabolism. Ayurveda mentioned that improper dietary habits and sedentary life style affects state of Agni which resulted Ama production and finally leading to the metabolic syndrome. The vitiation of Dosha, diminish state of Dhatu and blockage of channels, etc. also can initiate pathogenesis of metabolic disorders. The Kayachikitsa branch of Ayurveda recommended use of internal medicine for the management of various metabolic disorders. Considering increased health burden of society due to the metabolic syndrome present article explore role of ayurveda internal medicine for the management of metabolic syndrome. Keywords: Ayurveda, metabolic syndrome, Santarpanjanya, Madhumeha and Sthoulya.      &nbsp

    Optimization of the structural and control system for LSS with reduced-order model

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    The objective is the simultaneous design of the structural and control system for space structures. The minimum weight of the structure is the objective function, and the constraints are placed on the closed loop distribution of the frequencies and the damping parameters. The controls approach used is linear quadratic regulator with constant feedback. A reduced-order control system is used. The effect of uncontrolled modes is taken into consideration by the model error sensitivity suppression (MESS) technique which modified the weighting parameters for the control forces. For illustration, an ACOSS-FOUR structure is designed for a different number of controlled modes with specified values for the closed loop damping parameters and frequencies. The dynamic response of the optimum designs for an initial disturbance is compared

    Speaker Recognition Based Home Automation Using Matlab

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    Due to decline in both physical and mental abilities, some elderly are not allowed to leave the bed without assistance. Some time they are unable to make the desirable bodily movements and repositioning. In this paper the home automation is obtained using MATLAB based speaker recognition. The feature extraction of speech signal is done by using MFCC and for selection of features of speech signal vector quantization is used. By using above two steps the speaker is recognized and then this is given to the microcontroller by using serial communication .Then the particular home appliance get operated

    On the Approximability of Digraph Ordering

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    Given an n-vertex digraph D = (V, A) the Max-k-Ordering problem is to compute a labeling :V[k]\ell : V \to [k] maximizing the number of forward edges, i.e. edges (u,v) such that \ell(u) < \ell(v). For different values of k, this reduces to Maximum Acyclic Subgraph (k=n), and Max-Dicut (k=2). This work studies the approximability of Max-k-Ordering and its generalizations, motivated by their applications to job scheduling with soft precedence constraints. We give an LP rounding based 2-approximation algorithm for Max-k-Ordering for any k={2,..., n}, improving on the known 2k/(k-1)-approximation obtained via random assignment. The tightness of this rounding is shown by proving that for any k={2,..., n} and constant ε>0\varepsilon > 0, Max-k-Ordering has an LP integrality gap of 2 - ε\varepsilon for nΩ(1/loglogk)n^{\Omega\left(1/\log\log k\right)} rounds of the Sherali-Adams hierarchy. A further generalization of Max-k-Ordering is the restricted maximum acyclic subgraph problem or RMAS, where each vertex v has a finite set of allowable labels SvZ+S_v \subseteq \mathbb{Z}^+. We prove an LP rounding based 42/(2+1)2.3444\sqrt{2}/(\sqrt{2}+1) \approx 2.344 approximation for it, improving on the 222.8282\sqrt{2} \approx 2.828 approximation recently given by Grandoni et al. (Information Processing Letters, Vol. 115(2), Pages 182-185, 2015). In fact, our approximation algorithm also works for a general version where the objective counts the edges which go forward by at least a positive offset specific to each edge. The minimization formulation of digraph ordering is DAG edge deletion or DED(k), which requires deleting the minimum number of edges from an n-vertex directed acyclic graph (DAG) to remove all paths of length k. We show that both, the LP relaxation and a local ratio approach for DED(k) yield k-approximation for any k[n]k\in [n].Comment: 21 pages, Conference version to appear in ESA 201

    All quantum states useful for teleportation are nonlocal resources

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    Understanding the relation between the different forms of inseparability in quantum mechanics is a longstanding problem in the foundations of quantum theory and has implications for quantum information processing. Here we make progress in this direction by establishing a direct link between quantum teleportation and Bell nonlocality. In particular, we show that all entangled states which are useful for teleportation are nonlocal resources, i.e. lead to deterministic violation of Bell's inequality. Our result exploits the phenomenon of super-activation of quantum nonlocality, recently proved by Palazuelos, and suggests that the latter might in fact be generic.Comment: 4 pages. v2: Title and abstract changed, presentation improved, references updated, same result

    How to Play Unique Games on Expanders

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    In this note we improve a recent result by Arora, Khot, Kolla, Steurer, Tulsiani, and Vishnoi on solving the Unique Games problem on expanders. Given a (1ε)(1-\varepsilon)-satisfiable instance of Unique Games with the constraint graph GG, our algorithm finds an assignment satisfying at least a 1Cε/hG1- C \varepsilon/h_G fraction of all constraints if ε<cλG\varepsilon < c \lambda_G where hGh_G is the edge expansion of GG, λG\lambda_G is the second smallest eigenvalue of the Laplacian of GG, and CC and cc are some absolute constants

    Hitting Diamonds and Growing Cacti

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    We consider the following NP-hard problem: in a weighted graph, find a minimum cost set of vertices whose removal leaves a graph in which no two cycles share an edge. We obtain a constant-factor approximation algorithm, based on the primal-dual method. Moreover, we show that the integrality gap of the natural LP relaxation of the problem is \Theta(\log n), where n denotes the number of vertices in the graph.Comment: v2: several minor changes
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