Academic literature on the topic 'LINEAR POSITIVE OPERATORS'

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Journal articles on the topic "LINEAR POSITIVE OPERATORS"

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Pethe, S. "Corrigendum: ‘On Linear Positive Operators’." Journal of the London Mathematical Society s2-40, no. 2 (October 1989): 267–68. http://dx.doi.org/10.1112/jlms/s2-40.2.267-s.

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Özarslan, Mehmet. "q -Laguerre type linear positive operators." Studia Scientiarum Mathematicarum Hungarica 44, no. 1 (March 1, 2007): 65–80. http://dx.doi.org/10.1556/sscmath.44.2007.1.7.

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The main object of this paper is to define the q -Laguerre type positive linear operators and investigate the approximation properties of these operators. The rate of convegence of these operators are studied by using the modulus of continuity, Peetre’s K -functional and Lipschitz class functional. The estimation to the difference | Mn +1, q ( ƒ ; χ )− Mn , q ( ƒ ; χ )| is also obtained for the Meyer-König and Zeller operators based on the q -integers [2]. Finally, the r -th order generalization of the q -Laguerre type operators are defined and their approximation properties and the rate of convergence of this r -th order generalization are also examined.
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Popa, Dorian, and Ioan Raşa. "Steklov averages as positive linear operators." Filomat 30, no. 5 (2016): 1195–201. http://dx.doi.org/10.2298/fil1605195p.

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Duman, O., and C. Orhan. "Statistical approximation by positive linear operators." Studia Mathematica 161, no. 2 (2004): 187–97. http://dx.doi.org/10.4064/sm161-2-6.

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Park, Choon-Kil, and Jong-Su An. "POSITIVE LINEAR OPERATORS IN C*-ALGEBRAS." Bulletin of the Korean Mathematical Society 46, no. 5 (September 30, 2009): 1031–40. http://dx.doi.org/10.4134/bkms.2009.46.5.1031.

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Gadjiev, Akif, Oktay Duman, and A. M. Ghorbanalizadeh. "Ideal Convergence ofk-Positive Linear Operators." Journal of Function Spaces and Applications 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/178316.

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We study some ideal convergence results ofk-positive linear operators defined on an appropriate subspace of the space of all analytic functions on a bounded simply connected domain in the complex plane. We also show that our approximation results with respect to ideal convergence are more general than the classical ones.
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Demirci, Kamil, and Sevda Karakuş. "StatisticalA-summability of positive linear operators." Mathematical and Computer Modelling 53, no. 1-2 (January 2011): 189–95. http://dx.doi.org/10.1016/j.mcm.2010.08.003.

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Atlihan, Ö. G., and C. Orhan. "Summation process of positive linear operators." Computers & Mathematics with Applications 56, no. 5 (September 2008): 1188–95. http://dx.doi.org/10.1016/j.camwa.2008.02.020.

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Gavrea, I., H. H. Gonska, and D. P. Kacsó. "Positive linear operators with equidistant nodes." Computers & Mathematics with Applications 32, no. 8 (October 1996): 23–32. http://dx.doi.org/10.1016/0898-1221(96)00163-0.

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Atlihan, Özlem G., and Cihan Orhan. "Matrix Summability and Positive Linear Operators." Positivity 11, no. 3 (August 2007): 387–98. http://dx.doi.org/10.1007/s11117-007-2049-y.

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Dissertations / Theses on the topic "LINEAR POSITIVE OPERATORS"

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Eveson, S. P. "Theory and application of Hilbert's projective metric to linear and nonlinear problems in positive operator thoery." Thesis, University of Sussex, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316513.

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Gosselin, Frédéric. "Modèles stochastiques d'extinction de population : propriétés mathématiques et leurs applications." Paris 6, 1997. http://www.theses.fr/1997PA066358.

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Des modeles d'extinction de population sont frequemment employes comme outils d'aide a la decision pour la gestion de populations animales ou vegetales menacees. Le but de cette these est de prouver des resultats mathematiques decrivant la maniere dont se passe l'extinction dans la plupart de ces modeles, et de les appliquer a quelques cas particuliers. Apres une revue bibliographique sur l'extinction de populations et les modeles utilises pour l'apprehender, je propose une serie de resultats mathematiques, pour la plupart asymptotiques, generalisant au cadre plus etendu des chaines de markov a espace d'etats denombrable des resultats connus pour les chaines de markov finies ou les processus de ramification. Je prouve l'extinction certaine de ces modeles et deux types de stabilisation stochastique et asymptotique conditionnellement a la non-extinction. C'est l'utilisation de resultats d'analyse lineaire qui aura permis une telle extension. Je presente ensuite deux manieres de simuler numeriquement ces modeles, dont l'une est en partie nouvelle, puis j'etudie a la lumiere des resultats de cette these un modele d'extinction correspondant a une population reelle. Je clos ce travail par une discussion sur l'applicabilite, l'utilisation et l'utilite de mes resultats pour la modelisation de l'extinction, mais aussi dans d'autres domaines biologiques. Les principales conclusions sont que mes resultats s'appliquent a un grand nombre de modeles d'extinction existants et possedent des applications conceptuelles interessantes en ecologie theorique, concernant les notions d'equilibre et de stabilite, mais qu'ils ne sont pas systematiquement utiles dans l'interpretation des simulations et qu'ils doivent etre utilises avec une certaine rigueur mathematique
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Bai, Guo-Deng, and 白國燈. "Rate of convergence of positive linear operators for." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/90535227167951811421.

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碩士
國立中央大學
數學系
86
In the present paper we estimate convergence rates of approximation for functions of bounded variation, for functions which are exponentially bounded and locally of bounded variation, for functions with derivatives of bounded vairation, and for functions which are exponentially bounded and with derivatives locally of bounded variation, using general integral operators with probability kernels. Let $L_n(f,x):=\int_D f( t) d_t m_n(x,t)$ be the sequence of positive linear operators where $D=[0,\infty)$ or $D=R$, and $m_n(x,\cdot)$ is a probability measure$D$ for each $x \in D$. The rate of convergence are determined by estimating $|L_n(f,x)-{1 \over 2} (f(x+)+f(x-))|$ and $|L_n(f,x)-f(x)|$ in terms of certain bounds. The generalesult is then applied to produce estimate for particular operators, such as Phillips operators, Baskakov operators, Mirakjan-Sz\''asz operators, Post-Widder operators, and Gauss-Weierstrass operators. Application to them indicates that our methods cannot be asymptotically improved.
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PRATAP, RAM. "CERTAIN APPROXIMATION METHODS OF CONVERGENCE FOR LINEAR POSITIVE OPERATORS." Thesis, 2020. http://dspace.dtu.ac.in:8080/jspui/handle/repository/18097.

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The present thesis deals with the approximation behavior of various linear positive operators, their modifications, and approximation properties like rate of convergence, error estimation, and graphical comparison. We segregate the thesis in seven chapters. Chapter 1 is an introduction that contains a history of approximation theory, basic definitions, and converging tools which play an important role in approximation theory. Chapter 2 is divided into three sections. In the first section, we have considered the Kantorovich form of α−Bernstein operators introduced by Chen et al. [36]. We discussed some auxiliary properties and study the direct local approximation theorem, Voronovskaya type asymptotic, and function of bounded variation for α−BernsteinKantorovich operators. In the second section, we have considered the q-analogue of α-Bernstein Kantorovich operators. For these proposed operators, we studied some convergence properties by using first and second-order modulus of continuity. In the last section, we have proposed the Stancu type generalization of the family of Bernstein Kantorovich operators involving parameter α ∈ [0,1] with Shifted Knots. These operators provide the pliability to approximate on the interval [0,1] and over its subintervals. For the proposed operators, we investigate some basic results of approximation and their rate of convergence in terms of first and second-order modulus of continuity, Lipschitz class, and Lipschitz-type function. We also estimate the global rate of convergence of the operators with the help of the Ditzian-Totik modulus of smoothness. Moreover, the p th order generalization of the operators is established. Some numerical simulation and graphical comparisons are given for a better depiction of theoretical results. xiii In chapter 3, we propose the Kantorovich type generalized Szász-Mirakyan operators based on Jain and Pethe operators [101]. We study local approximation results in terms of classical modulus of continuity as well as Ditzian-Totik moduli of smoothness. Further, we establish the rate of convergence in a class of absolutely continuous functions having a derivative coinciding a.e. with a function of bounded variation. In chapter 4, we propose the integral form of Jain and Pethe operators associated with the Baskakov operators and study some basic properties. We estimate the rate of convergence, Voronovskaja type asymptotic estimate formula, and weighted approximation of these operators. In chapter 5, we consider new operators, which are defined by Gupta and Srivastava [90]. They considered a general sequence of positive linear operators and gave the modified form of their previous operators [142]. As these operators preserve linear functions, we call these operators as genuine Gupta-Srivastava operators. Here we discuss some basic properties, direct results, rate of convergence for a class of functions whose derivatives are of bounded variation, and weighted approximation for our considered operators. In chapter 6, we propose the Bézier variant of the Gupta-Srivastava operators [90] and discuss some direct convergence results by using Lipschitz type spaces, Ditzian-Totik modulus of smoothness, weighted modulus of continuity, and for functions whose derivatives are of bounded variation. In the end, some graphical representation for comparison with other variants has been presented. In chapter 7, we consider mixed approximation operators based on the second-kind beta transform by using Szász-Mirakyan operators. For the proposed operators, we establish direct result, Voronovskaya type theorem, quantitative Voronovskaya type theorem, Grüss Voronovskaya type theorem, weighted approximation, and functions of bounded variation.
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蔡明誠. "Approximation of Unbounded Continuous Functions by Some Positive Linear Operators." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/77662911293417442059.

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Ru, Huang Yi, and 黃怡儒. "Rates of Approximation for Positive Linear Operators via Maximal Functions." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/92805795847474695219.

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碩士
國立中央大學
數學系
81
Weierstrass 在 1885 年証明了定義在閉區間[a,b]的連續實函數可以用 多項式均勻逼近。S. N. Bernstein 更証明了定義在[0,1]上的連續實函 數可以用 Bernstein 多項式均勻逼近。在 1952 年 Bohman和 Korovkin 更進一步地將它推廣到一般的正線性算子。Bohman-Koro- vkin 定理証明 了如果 {L} 是由定義在所有在 [a,b] 上連續的函數所成的集合 C[a,b] 上的正線性算子所組成的數列,並滿足 L(1,x).arrl r.1, L(t,x).arrlr. x, L(t^2,x).arrlr.x^2 在 [a,b] 上均勻收斂,則對所有在 C[a,b] 上 的函數 f,L(f,x) 在 [a,b] 上均勻收斂到 f(x)。自從此定理建立後,有 許多人開始著手於逼近速度的建立。其中 B. Lenze 在 1991 年用 Lipschitz-type 和 Calderon-Scott-type 極值函數對 Bernstein 算子 和 Kantorovic 算子求得個別的逼近速度。本文的目的是推廣 Lenze 的 方法對一般的正線性算子做估計,求出利用 Lipschitz-type 極值函數所 得的一般正線性算子的逼近速度。並推廣 Lenze 的結果求出利用 Lipschitz-type 極值函數所得的 k 維擴展的 Bernstein 算子的逼近速 度和利用 Calderon-Scott-type 極值函數所得的 k 維擴展的 Kantorovic 算子的逼近速度。另外我們也將實際應用這些結果來估計一 些算子的逼近速度。例如 Durrymeyer 算子, Szasz-Mirakjan 算子,以及 算子 Q 。
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Piţul, Paula [Verfasser]. "Evaluation of the approximation order by positive linear operators / von Paula Anamaria Piţul." 2007. http://d-nb.info/988401487/34.

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Tasi, Yu-Dian, and 蔡育典. "Certain Positive Linear Operators Constructed by Some Special Functions and Some Difference Equations." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/86791135148341087296.

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碩士
淡江大學
數學學系碩士班
99
For sequence , {c_(n)}, we consider the following difference equation. a_(n)=a_(n+1)-c_(n){[a_(n+1)]^2-S^2}. We will apply the method of backward induction to establish the existence, the uniqueness and behavior of the solution under certain conditions. We know that the difference equation has bounded monotone solution if the positive series sum_{n=1}^infinity c_(n) is convergent. However, the difference equation has no unbounded solution if the positive series sum_{n=1}^infinity c_(n) is divergent. Finally, we consider the existence, the uniqueness and behavior of the solution of the difference equation under sum_{n=1}^infinity c_(n) is not positive series.
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Books on the topic "LINEAR POSITIVE OPERATORS"

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Gupta, Vijay, and Gancho Tachev. Approximation with Positive Linear Operators and Linear Combinations. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-58795-0.

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Păltănea, Radu. Approximation Theory Using Positive Linear Operators. Boston, MA: Birkhäuser Boston, 2004. http://dx.doi.org/10.1007/978-1-4612-2058-9.

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Positive transfer operators and decay of correlations. Singapore: World Scientific Pub. Co., 2000.

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Gupta, Vijay, and Michael Th Rassias. Moments of Linear Positive Operators and Approximation. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-19455-0.

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Krasnosel'skij, M. A. Postive linear systems: The method of positive operators. Berlin: Heldermann Verlag, 1989.

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Karim, Boulabiar, Buskes Gerard, and Triki Abdelmajid, eds. Positivity. Basel: Birkhäuser, 2007.

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Størmer, Erling. Positive Linear Maps of Operator Algebras. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-34369-8.

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Størmer, Erling. Positive Linear Maps of Operator Algebras. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013.

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Keimel, Klaus. Ordered cones and approximation. Berlin: Springer-Verlag, 1992.

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Aliprantis, Charalambos D., and Owen Burkinshaw. Positive Operators. Springer, 2006.

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Book chapters on the topic "LINEAR POSITIVE OPERATORS"

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Simons, Stephen. "Discontinuous positive linear operators." In Lecture Notes in Mathematics, 141–51. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/bfb0093642.

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Bhatia, Rajendra, and Ludwig Elsner. "Positive Linear Maps and the Lyapunov Equation." In Linear Operators and Matrices, 107–20. Basel: Birkhäuser Basel, 2002. http://dx.doi.org/10.1007/978-3-0348-8181-4_9.

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Gupta, Vijay, and Gancho Tachev. "Moments and Combinations of Positive Linear Operators." In Approximation with Positive Linear Operators and Linear Combinations, 1–14. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-58795-0_1.

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Gupta, Vijay, and Gancho Tachev. "Direct Estimates for Some New Operators." In Approximation with Positive Linear Operators and Linear Combinations, 117–55. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-58795-0_7.

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Katkova, Olga M., and Anna M. Vishnyakova. "Linear Operators Preserving the Set of Positive (Nonnegative) Polynomials." In Positive Systems, 83–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-02894-6_8.

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Păltănea, Radu. "Estimates for the Bernstein Operators." In Approximation Theory Using Positive Linear Operators, 89–129. Boston, MA: Birkhäuser Boston, 2004. http://dx.doi.org/10.1007/978-1-4612-2058-9_4.

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Soybaş, Danyal, and Neha Malik. "Results Concerning Certain Linear Positive Operators." In Computational Mathematics and Variational Analysis, 441–64. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44625-3_24.

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Mursaleen, M., and S. A. Mohiuddine. "Statistical Approximation of Positive Linear Operators." In Convergence Methods for Double Sequences and Applications, 133–48. New Delhi: Springer India, 2014. http://dx.doi.org/10.1007/978-81-322-1611-7_8.

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Agrawal, P. N., and Meenu Goyal. "Bivariate Extension of Linear Positive Operators." In Mathematical Analysis, Approximation Theory and Their Applications, 15–62. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-31281-1_2.

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Gupta, Vijay, and Michael Th Rassias. "Some Positive Linear Operators and Moments." In SpringerBriefs in Mathematics, 1–24. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-19455-0_1.

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Conference papers on the topic "LINEAR POSITIVE OPERATORS"

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Ünver, Mehmet. "Abel transforms of positive linear operators." In 11TH INTERNATIONAL CONFERENCE OF NUMERICAL ANALYSIS AND APPLIED MATHEMATICS 2013: ICNAAM 2013. AIP, 2013. http://dx.doi.org/10.1063/1.4825711.

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Özger, Faruk. "Statistical Approximation Properties of Some Positive Linear Operators." In International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.032.

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Statistical convergence is an important concept in functional analysis. In this work, we give a short survey about statistical convergence and statistical convergence of some positive linear operators to approximate functions.
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Mishra, Lakshmi Narayan, A. Srivastava, T. Khan, S. A. Khan, and Vishnu Narayan Mishra. "Inverse theorems for some linear positive operators using Beta and Baskakov basis functions." In INTERNATIONAL CONFERENCE ON RECENT TRENDS IN APPLIED MATHEMATICAL SCIENCES (ICRTAMS-2020). AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0062925.

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Fortin, Marie, Boris Konev, Vladislav Ryzhikov, Yury Savateev, Frank Wolter, and Michael Zakharyaschev. "Unique Characterisability and Learnability of Temporal Instance Queries." In 19th International Conference on Principles of Knowledge Representation and Reasoning {KR-2022}. California: International Joint Conferences on Artificial Intelligence Organization, 2022. http://dx.doi.org/10.24963/kr.2022/17.

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We aim to determine which temporal instance queries can be uniquely characterised by a (polynomial-size) set of positive and negative temporal data examples. We start by considering queries formulated in fragments of propositional linear temporal logic LTL that correspond to conjunctive queries (CQs) or extensions thereof induced by the until operator. Not all of these queries admit polynomial characterisations, but by imposing a further restriction to path-shaped queries we identify natural classes that do. We then investigate how far the obtained characterisations can be lifted to temporal knowledge graphs queried by 2D languages combining LTL with concepts in description logics EL or ELI (i.e., tree-shaped CQs). While temporal operators in the scope of description logic constructors can destroy polynomial characterisability, we obtain general transfer results for the case when description logic constructors are within the scope of temporal operators. Finally, we apply our characterisations to establish (polynomial) learnability of temporal instance queries using membership queries in the active learning framework.
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Lin, Shing-Hong, Thomas F. Krile, and John F. Walkup. "Optical polynomial processing based on the bilinear transform." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.thl1.

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With the motivation to extend linear/bilinear operators to a more general class of nonlinear operators via a Volterra series (polynomial) approximation, we look into optical polynomial implementations using a factored representation so that presently known bilinear techniques can be employed. Since there are two inputs and one kernel in the generalized bilinear transform, the two inputs act as polynomial input variables and the elements in the kernel represent coefficients of the quadratic polynomial. Thus higher polynomial processing can be realized by iterating the bilinear transform. A dual-LCLV system is proposed to form such a quadratic polynomial. With electronic or optical feedback, a general optical polynomial processor is achievable. The work has been extended to perform bipolar complex analog and binary digital polynomial operations. The analog operations are performed by using separate parallel channels for real/imaginary and positive/negative numbers and making use of triple matrix-matrix product processing. Systolic and wavefront processors and a triple product processor are used to implement binary digital polynomial processing.
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Georgiou, Ioannis T., and Christos I. Papadopoulos. "Developing Pod Over the Complex Plane to Form a Data Processing Tool for Finite Element Simulations of Steady State Structural Dynamics." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-15359.

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To analyze the steady state response of structural dynamical systems with multi-field response (example, Timoshenko shearable rod) given complex-valued databases (finite element simulations of complexified equations of motion), we have developed a Complex Proper Orthogonal Decomposition (CPOD) transform. Like the regular multi-field POD, the development of the C-POD is based on the primitive space and frequency auto-correlation operations. These data fusion operations give rise to complex Hermitian operators whose solution determines the C-POD transform. The eigen-values of the complex Hermitian operators are strictly positive and it is shown that they represent the energy fractions of the auto-correlation energy contained in the POD modes. The POD modes have both amplitudes and shapes that are complex-valued scalar functions. The C-POD transform is verified by applying it to characterize the finite element simulations of the steady state dynamics of planar beams and arches. It turns out that the real part of the shape of a POD mode coincides with the shape of the linear POD; whereas its amplitude is a localized function of frequency at a critical frequency which is identical to a natural frequency.
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Berry, L. A. "Positive Quasi Linear Operator Formulation." In RADIO FREQUENCY POWER IN PLASMAS: 16th Topical Conference on Radio Frequency Power in Plasmas. AIP, 2005. http://dx.doi.org/10.1063/1.2098192.

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Balas, Mark J., and Susan A. Frost. "A Stabilization of Fixed Gain Controlled Infinite Dimensional Systems by Augmentation With Direct Adaptive Control." In ASME 2017 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/smasis2017-3726.

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Linear infinite dimensional systems are described by a closed, densely defined linear operator that generates a continuous semigroup of bounded operators on a general Hilbert space of states and are controlled via a finite number of actuators and sensors. Many distributed applications are included in this formulation, such as large flexible aerospace structures, adaptive optics, diffusion reactions, smart electric power grids, and quantum information systems. We have developed the following stability result: an infinite dimensional linear system is Almost Strictly Dissipative (ASD) if and only if its high frequency gain CB is symmetric and positive definite and the open loop system is minimum phase, i.e. its transmission zeros are all exponentially stable. In this paper, we focus on infinite dimensional linear systems for which a fixed gain linear infinite or finite dimensional controller is already in place. It is usually true that fixed gain controllers are designed for particular applications but these controllers may not be able to stabilize the plant under all variations in the operating domain. Therefore we propose to augment this fixed gain controller with a relatively simple direct adaptive controller that will maintain stability of the full closed loop system over a much larger domain of operation. This can ensure that a flexible structure controller based on a reduced order model will still maintain closed-loop stability in the presence of unmodeled system dynamics. The augmentation approach is also valuable to reduce risk in loss of control situations. First we show that the transmission zeros of the augmented infinite dimensional system are the open loop plant transmission zeros and the eigenvalues (or poles) of the fixed gain controller. So when the open-loop plant transmission zeros are exponentially stable, the addition of any stable fixed gain controller does not alter the stability of the transmission zeros. Therefore the combined plant plus controller is ASD and the closed loop stability when the direct adaptive controller augments this combined system is retained. Consequently direct adaptive augmentation of controlled linear infinite dimensional systems can produce robust stabilization even when the fixed gain controller is based on approximation of the original system. These results are illustrated by application to a general infinite dimensional model described by nuclear operators with compact resolvent which are representative of distributed parameter models of mechanically flexible structures. with a reduced order model based controller and adaptive augmentation.
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Law, C. K., and Phoenix S. Y. Poon. "Negativity of Gaussian states in noisy environment: Interpretations and Applications." In Workshop on Entanglement and Quantum Decoherence. Washington, D.C.: Optica Publishing Group, 2008. http://dx.doi.org/10.1364/weqd.2008.edd3.

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We reexamine the interpretation of negativity of a generally mixed two-mode Gaussian state by diagonalizing ρ TA (the partial transposition of density matrix ρ) directly. We show that negativity can be explicitly expressed in terms of an optimal uncertainty product corresponding to the greatest violation of a separability criterion based on positive partial transposition [1], In addition, the explicit form of the eigenvectors of ρ ta provides a way to construct entanglement witness operators [2]. We apply our analysis of negativity to disentanglement dynamics in two physical situations in optics. First, we study two-mode squeezed states interacting with symmetric linear baths. Second, we study the decoherence of hyper-entangled two-photon states due to polarization mode dispersion in optical fibers. In both problems, we present the time-dependence of negativity and indicate how the disentanglement times depend on system parameters.
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Shan, Youngbin, Yaoguang Wu, Aiguo Hu, and Fanlei Li. "Interactive Analysis (IRA) Determining Focal Reservoir Parameters Dominating Estimated Ultimate Recovery (EUR)." In Gas & Oil Technology Showcase and Conference. SPE, 2023. http://dx.doi.org/10.2118/214115-ms.

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Abstract Interactive Analysis (IRA) is a new reservoir study method which applies to both condensate oil & gas reservoir and conventional oil & gas reservoir. IRA establishes the correspondence between stage EUR equivalents and reservoir parameters. Often, reservoir parameters include but not limited to porosity, permeability, burst pressure, Poisson rate, Oil saturation or Gas content, Free gas content and adsorption gas content, pay zone thickness, resistivity, mud content, etc. In a specific compartmentalization, it is important to decide which parameter is the focal parameter dominating the productivity. If the focal parameters can be decided, operators can use this evidence to decide which zone and which sub-zone drilling must fully penetrate through. Additional, when well is designed for hydraulic fracturing, engineers can use this data to design stages and clusters. Designing of higher focal parameter quality in stage and cluster is certainly a contribution to better frac efficiency and EUR. IRA is expressed that the Normalized Correlated Coefficient (NCC) Vector is equal to the Moore-Penrose inverse of the Normalized Reservoir Parameter Quality Factors (NRPQF) matrix multiplying the Normalized EUR equivalent (NEE) vector. NCC deriving from the IRA represents the weight of productivity contribution to EUR. Analyzing IRA equation, the focal parameters dominating the well EUR can be determined. With focal parameters available, operators can optimize the drilling criteria and optimize frac design. For a specific compartmentalization, the focal parameters derived from IRA shall give consistent focal parameters which dominate the higher productivity and lower productivity. When a well is hydraulic fractured, the NEE can be tested and analyzed. To input the NEE into IRA equation, the frac efficiency is also reflected by NEE. Three shale gas wells in a compartmentalization are analyzed via IRA analysis. The positive focal parameters, irrelevant parameters and negative focal parameters in each well and overall averaging give good convergence. Two wells in condensate oil pay zone in a compartmentalization are also analyzed via IRA analysis. The positive focal parameters, irrelevant parameters and negative focal parameters in each well and overall averaging give some convergence. If a NCC is bigger, it dominates EUR. If it is small or very small, the contribution to EUR is less or measily. On the other hand, if a NCC is positive, it increases the productivity when the parameter quality is higher. If a NCC is negative, it decreases the productivity when the parameter quality is higher. No focal parameter dominating EUR can be understood until IRA is proposed. Rather than reservoir mechanics analysis, IRA gives explicit linear mathematical expression which makes engineers easier to calculate by aid of Matlab coding. IRA analysis is a breakthrough to understand the intrinsic structure between reservoir parameters and EUR.
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Reports on the topic "LINEAR POSITIVE OPERATORS"

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McPhedran, R., K. Patel, B. Toombs, P. Menon, M. Patel, J. Disson, K. Porter, A. John, and A. Rayner. Food allergen communication in businesses feasibility trial. Food Standards Agency, March 2021. http://dx.doi.org/10.46756/sci.fsa.tpf160.

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Background: Clear allergen communication in food business operators (FBOs) has been shown to have a positive impact on customers’ perceptions of businesses (Barnett et al., 2013). However, the precise size and nature of this effect is not known: there is a paucity of quantitative evidence in this area, particularly in the form of randomised controlled trials (RCTs). The Food Standards Agency (FSA), in collaboration with Kantar’s Behavioural Practice, conducted a feasibility trial to investigate whether a randomised cluster trial – involving the proactive communication of allergen information at the point of sale in FBOs – is feasible in the United Kingdom (UK). Objectives: The trial sought to establish: ease of recruitments of businesses into trials; customer response rates for in-store outcome surveys; fidelity of intervention delivery by FBO staff; sensitivity of outcome survey measures to change; and appropriateness of the chosen analytical approach. Method: Following a recruitment phase – in which one of fourteen multinational FBOs was successfully recruited – the execution of the feasibility trial involved a quasi-randomised matched-pairs clustered experiment. Each of the FBO’s ten participating branches underwent pair-wise matching, with similarity of branches judged according to four criteria: Food Hygiene Rating Scheme (FHRS) score, average weekly footfall, number of staff and customer satisfaction rating. The allocation ratio for this trial was 1:1: one branch in each pair was assigned to the treatment group by a representative from the FBO, while the other continued to operate in accordance with their standard operating procedure. As a business-based feasibility trial, customers at participating branches throughout the fieldwork period were automatically enrolled in the trial. The trial was single-blind: customers at treatment branches were not aware that they were receiving an intervention. All customers who visited participating branches throughout the fieldwork period were asked to complete a short in-store survey on a tablet affixed in branches. This survey contained four outcome measures which operationalised customers’: perceptions of food safety in the FBO; trust in the FBO; self-reported confidence to ask for allergen information in future visits; and overall satisfaction with their visit. Results: Fieldwork was conducted from the 3 – 20 March 2020, with cessation occurring prematurely due to the closure of outlets following the proliferation of COVID-19. n=177 participants took part in the trial across the ten branches; however, response rates (which ranged between 0.1 - 0.8%) were likely also adversely affected by COVID-19. Intervention fidelity was an issue in this study: while compliance with delivery of the intervention was relatively high in treatment branches (78.9%), erroneous delivery in control branches was also common (46.2%). Survey data were analysed using random-intercept multilevel linear regression models (due to the nesting of customers within branches). Despite the trial’s modest sample size, there was some evidence to suggest that the intervention had a positive effect for those suffering from allergies/intolerances for the ‘trust’ (β = 1.288, p<0.01) and ‘satisfaction’ (β = 0.945, p<0.01) outcome variables. Due to singularity within the fitted linear models, hierarchical Bayes models were used to corroborate the size of these interactions. Conclusions: The results of this trial suggest that a fully powered clustered RCT would likely be feasible in the UK. In this case, the primary challenge in the execution of the trial was the recruitment of FBOs: despite high levels of initial interest from four chains, only one took part. However, it is likely that the proliferation of COVID-19 adversely impacted chain participation – two other FBOs withdrew during branch eligibility assessment and selection, citing COVID-19 as a barrier. COVID-19 also likely lowered the on-site survey response rate: a significant negative Pearson correlation was observed between daily survey completions and COVID-19 cases in the UK, highlighting a likely relationship between the two. Limitations: The trial was quasi-random: selection of branches, pair matching and allocation to treatment/control groups were not systematically conducted. These processes were undertaken by a representative from the FBO’s Safety and Quality Assurance team (with oversight from Kantar representatives on pair matching), as a result of the chain’s internal operational restrictions.
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2

Crouch, Alfred E. PR-15-923-R01 Planning Strategy on In-Line Inspection Tool to Detect and Size Longitudinal Cracks. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), January 1990. http://dx.doi.org/10.55274/r0011386.

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Pipeline operators, through several industry surveys, have expressed a need for in-line inspection services to detect and size stress-corrosion cracking (SCC). The reality of the SCC situation has become apparent in published literature and has been acknowledged by the NDT Supervisory Committee of the Pipeline Research Committee (PRC) in a position paper that calls for support of a cooperative program to develop SCC ILl by 1995. The project reported in this document was designed to help structure that program. The project objectives were to identify and recommend needed nondestructive evaluation (NUE) research and to conceive a cooperative financing plan by which the costs of development could be shared by all industry components.
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Tetreault, Brian, Marin Kress, and Patricia DiJoseph. AIS data case study : evaluating reception of AIS position reports on the Missouri River by LOMA AIS sites in April and August 2020. Engineer Research and Development Center (U.S.), January 2022. http://dx.doi.org/10.21079/11681/42980.

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This Coastal and Hydraulics Engineering Technical Note (CHETN) describes a method for evaluating the received coverage from Automatic Identification System (AIS) shoreside sites along the Missouri River managed by the US Army Corps of Engineers (USACE) Lock Operations Management Application (LOMA), and presents the results of that analysis. The purpose is to identify AIS coverage gaps in the current system. Reception of AIS transmissions between shore-based transceivers and vessels is generally line-of-sight between the vessel and the AIS site antenna. However, signal reception may be affected by factors such as the distance and terrain between the vessel and the transceiver site, quality of the transceiver installation, state of the equipment either aboard the vessel or at the shore transceiver station, and atmospheric phenomena. Quantifying coverage gaps along the inland waterways system can inform research that uses AIS data, provide information on the performance of the AIS network, and provide guidance for efforts to address coverage gaps to improve navigation safety. In autumn 2020, severe shoaling was occurring on the Missouri River. As the shoals were identified, the Kansas City District requested the LOMA system transmit AIS Aid to Navigation (AtoN) to mark the shoals in several critical areas. However, vessel pilots sometimes reported that they were not receiving the AIS AtoN being transmitted. At the request of the Kansas City District, the US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory (ERDC-CHL), conducted a coverage analysis using data collected from the LOMA AIS transceivers in the area to determine if there were coverage issues and their extent and to aid in determining the best means of addressing any coverage gaps.
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Hailiang, Zhang, Wang Fuxiang, Sha Shengyi, Dai Lianshuang, Xuan Wenbo, and Ren Zhong. PR-469-173823-R01 In Line Inspection and Evaluation of Pinholes in Oil and Gas Pipelines. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 2019. http://dx.doi.org/10.55274/r0011604.

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Pinhole leaks have been reported as a significant cause of oil and gas pipeline failures in recent years. From 2010 to 2015, at least 131 significant incidents involving oil and gas pipelines in the United States (101 and 30, respectively) were attributed to pinhole leaks. The 9th European Gas Pipeline Incident Data Group Report states that as of 2013, the five-year moving average failure frequency for pinholes was equal to an approximate annual rate of 0.105 failures per 1,000 kilometers of pipeline(1). Pinholes may result from normal pipeline corrosion during routine operations, such as microbiologically induced corrosion, or can be created by third-party activities, such as illegal tapping. These small leaks have become a major risk for many pipeline companies. Pinhole leaks are more likely to lead to serious consequences than larger leaks because they are difficult to discover through normal monitoring and patrolling. An undetected pinhole leak can lead to significant soil and groundwater pollution over time. The research objective of this project was to investigate the applicability of magnetic flux leakage (MFL) to the inspection of oil and gas pipelines for pinhole defects. The MFL signal may be affected by pinhole diameter, depth, position, and so on. MFL inline inspection (ILI) technologies from five vendors were tested in blind scenarios involving pipeline with manufactured defects. Multiple pull through tests, field dig verification, and sampling were conducted to assess the effectiveness of MFL-ILI in pinhole detection. An optimal practice was developed by comparing the gap between MFL tracks, sampling frequency, intensity of magnetic field, etc. This report also outlines tests conducted to investigate the feasibility of using hydrostatic testing to detect pinholes.
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Yatsymirska, Mariya. Мова війни і «контрнаступальна» лексика у стислих медійних текстах. Ivan Franko National University of Lviv, March 2023. http://dx.doi.org/10.30970/vjo.2023.52-53.11742.

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The article examines the language of the russian-ukrainian war of the 21st century based on the materials of compressed media texts; the role of political narratives and psychological-emotional markers in the creation of new lexemes is clarified; the verbal expression of forecasts of ukrainian and foreign analysts regarding the course of hostilities on the territory of Ukraine is shown. Compressed media texts reflect the main meanings of the language of the russian-ukrainian war in relation to the surrounding world. First of all, the media vocabulary was supplemented with neologisms – aggressive and sad: “rashism”, “denazification”, “katsapstan”, “orks”, “rusnia”, “kremlins”, “parebrik”, “in the swamps”, “nuclear dictator”, “putinism”, “two hundred” and others. Numerals acquired new expressive and evaluative meanings: “200s” (dead), “300s” (wounded), “400s” (russian military personnel who filed reports for termination of the contract), “500s” (hopelessly drunk russian soldiers, alcoholics who are unable to perform combat tasks). The language of war intensified the slogans of the struggle for state independence and people’s freedom. The scope of the greeting “Glory to Ukraine! – Glory to Heroes!”. New official holidays have appeared in the history of Ukraine since 2014: “Heroes of the Heavenly Hundred” Day (February 20), “Ukrainian Volunteer Day” (March 14), “Defenders and Defenders of Ukraine Day” (October 14), “Volunteer Day” (5 December). As you know, the professional holiday of the military is the Day of the Armed Forces of Ukraine” (December 6). A special style is characteristic of media texts on military topics: “Iron Force of Ukraine” (Iron Force of Ukraine), “digitize the Army” (for effective simulation of military operations); “grain corridor” (export of Ukrainian grain to African and European countries); “don’t let Ukraine lose” (the position of the Allies at the first stage of the war), “Ukraine must win!” (the position of the Allies in the second stage of the war); “in the Russian-Ukrainian war, the thinking of the 19th century collided with the thinking of the 21st century”, “a politician is a person who understands time” (Grigori Yavlinskyy, Russian oppositionist); “aggressive neutrality” (about Turkey’s position); “in Russia”, “there, in the swamps” (in Russia), “weak, inadequate evil” (about Russia), “behind the fence”; “a great reset of the world order”; “technology of military creativity”; “they are not Russian and not Ukrainian, they are Soviet”, “people without mentality”, “in Ukraine and without Ukraine” (Vitaly Portnikov about a separate category of Russian-speaking citizens in Ukraine); “information bed of Ukraine” (about combat operations on the front line; “when a descendant asks me what I did in those terrifying moments, I will know what to answer. At the very least, I did not stand aside” (opinion of a Ukrainian fighter). Compressed in media texts is implemented in the headline, note, infographic, chronicle, digest, help, caption for photos, blitz poll, interview, short articles, caricature, visual text, commercial, etc. Researchers add “nominative-representative text (business card text, titles of sections, pages, names of presenters, etc.) to concise media texts for a functional and pragmatic purpose.” accent text (quote, key idea); text-navigator (content, news feed, indication of movement or time); chronotope”. A specific linguistic phenomenon known as “language compression” is widespread in media texts. Language compression is the art of minimization; attention is focused on the main, the most essential, everything secondary is filtered out. Compression uses words succinctly and sparingly to convey the meaning as much as possible. For example, the headline “Racism. What is the essence of the new ideology of the Russian occupiers?”. The note briefly explains the meaning of this concept and explains the difference from “nazism” and “fascism”. Key words: compressed media text, language compression, language of war, emotional markers, expressive neologisms, political journalism.
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Plueddemann, Albert, Benjamin Pietro, and Emerson Hasbrouck. The Northwest Tropical Atlantic Station (NTAS): NTAS-19 Mooring Turnaround Cruise Report Cruise On Board RV Ronald H. Brown October 14 - November 1, 2020. Woods Hole Oceanographic Institution, January 2021. http://dx.doi.org/10.1575/1912/27012.

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The Northwest Tropical Atlantic Station (NTAS) was established to address the need for accurate air-sea flux estimates and upper ocean measurements in a region with strong sea surface temperature anomalies and the likelihood of significant local air–sea interaction on interannual to decadal timescales. The approach is to maintain a surface mooring outfitted for meteorological and oceanographic measurements at a site near 15°N, 51°W by successive mooring turnarounds. These observations will be used to investigate air–sea interaction processes related to climate variability. This report documents recovery of the NTAS-18 mooring and deployment of the NTAS-19 mooring at the same site. Both moorings used Surlyn foam buoys as the surface element. These buoys were outfitted with two Air–Sea Interaction Meteorology (ASIMET) systems. Each system measures, records, and transmits via Argos satellite the surface meteorological variables necessary to compute air–sea fluxes of heat, moisture and momentum. The upper 160 m of the mooring line were outfitted with oceanographic sensors for the measurement of temperature, salinity and velocity. Deep ocean temperature and salinity are measured at approximately 38 m above the bottom. The mooring turnaround was done on the National Oceanic and Atmospheric Administration (NOAA) Ship Ronald H. Brown, Cruise RB-20-06, by the Upper Ocean Processes Group of the Woods Hole Oceanographic Institution. The cruise took place between 14 October and 1 November 2020. The NTAS-19 mooring was deployed on 22 October, with an anchor position of about 14° 49.48° N, 51° 00.96° W in 4985 m of water. A 31-hour intercomparison period followed, during which satellite telemetry data from the NTAS-19 buoy and the ship’s meteorological sensors were monitored. The NTAS-18 buoy, which had gone adrift on 28 April 2020, was recovered on 20 October near 13° 41.96° N, 58° 38.67° W. This report describes these operations, as well as other work done on the cruise and some of the pre-cruise buoy preparations.
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