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REFINEMENTS OF THE NORM OF TWO ORTHOGONAL PROJECTIONS
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作者 Xiaohui LI Meiqi LIU Chunyuan DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1229-1243,共15页
In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm ineq... In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm inequalities for combination of orthogonal projections on a Hilbert space.Furthermore,we give necessary and sufficient conditions under which the norm of the above combination of o`rthogonal projections attains its optimal value. 展开更多
关键词 NORM orthogonal projection positive operator SPECTRAL block operator valued matrix
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Association between operative position and postoperative nausea and vomiting in patients undergoing laparoscopic sleeve gastrectomy
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作者 Zhao-Peng Li Yan-Cheng Song +3 位作者 Ya-Li Li Dong Guo Dong Chen Yu Li 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2088-2095,共8页
BACKGROUND Bariatric surgery is one of the most effective ways to treat morbid obesity,and postoperative nausea and vomiting(PONV)is one of the common complications after bariatric surgery.At present,the mechanism of ... BACKGROUND Bariatric surgery is one of the most effective ways to treat morbid obesity,and postoperative nausea and vomiting(PONV)is one of the common complications after bariatric surgery.At present,the mechanism of the high incidence of PONV after weight-loss surgery has not been clearly explained,and this study aims to investigate the effect of surgical position on PONV in patients undergoing bariatric surgery.AIM To explore the effect of the operative position during bariatric surgery on PONV.METHODS Data from obese patients,who underwent laparoscopic sleeve gastrectomy(LSG)in the authors’hospital between June 2020 and February 2022 were divided into 2 groups and retrospectively analyzed.Multivariable logistic regression analysis and the t-test were used to study the influence of operative position on PONV.RESULTS There were 15 cases of PONV in the supine split-leg group(incidence rate,50%)and 11 in the supine group(incidence rate,36.7%)(P=0.297).The mean operative duration in the supine split-leg group was 168.23±46.24 minutes and 140.60±32.256 minutes in the supine group(P<0.05).Multivariate analysis revealed that operative position was not an independent risk factor for PONV(odds ratio=1.192,95%confidence interval:0.376-3.778,P=0.766).CONCLUSION Operative position during LSG may affect PONV;however,the difference in the incidence of PONV was not statistically significant.Operative position should be carefully considered for obese patients before surgery. 展开更多
关键词 Postoperative nausea and vomiting Bariatric surgery Laparoscopic sleeve gastrectomy Operative positions OBESITY
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Feynman Path Integral Using Operator Integration in Banach Space
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作者 Reza R. Ahangar Erbil Cetin Serife Muge Ege 《Journal of Applied Mathematics and Physics》 2024年第2期432-444,共13页
Feynman-Path Integral in Banach Space: In 1940, R.P. Feynman attempted to find a mathematical representation to express quantum dynamics of the general form for a double-slit experiment. His intuition on several slits... Feynman-Path Integral in Banach Space: In 1940, R.P. Feynman attempted to find a mathematical representation to express quantum dynamics of the general form for a double-slit experiment. His intuition on several slits with several walls in terms of Lagrangian instead of Hamiltonian resulted in a magnificent work. It was known as Feynman Path Integrals in quantum physics, and a large part of the scientific community still considers them a heuristic tool that lacks a sound mathematical definition. This paper aims to refute this prejudice, by providing an extensive and self-contained description of the mathematical theory of Feynman Path Integration, from the earlier attempts to the latest developments, as well as its applications to quantum mechanics. About a hundred years after the beginning of modern physics, it was realized that light could in fact show behavioral characteristics of both waves and particles. In 1927, Davisson and Germer demonstrated that electrons show the same dual behavior, which was later extended to atoms and molecules. We shall follow the method of integration with some modifications to construct a generalized Lebesgue-Bochner-Stieltjes (LBS) integral of the form , where u is a bilinear operator acting in the product of Banach spaces, f is a Bochner summable function, and μ is a vector-valued measure. We will demonstrate that the Feynman Path Integral is consistent and can be justified mathematically with LBS integration approach. 展开更多
关键词 Feynman Path Integral Lebesgue-Bochner-Stieltjes Integral Operator Integral Particle-Wave Function Operator Integration Position and Momentum Operators
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Evaluation index system for positive operation of water conservancy projects 被引量:3
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作者 Qing-yuan ZHU Guo-hua FANG 《Water Science and Engineering》 EI CAS 2009年第4期110-117,共8页
The conditions for the positive operation of water conservancy projects are described in this paper. A scientific and effective evaluation index system was established based on frequency analysis, theoretical analysis... The conditions for the positive operation of water conservancy projects are described in this paper. A scientific and effective evaluation index system was established based on frequency analysis, theoretical analysis, and expert consultation. This evaluation index system can be divided into six first-level indices: the degree to which facilities are intact and functionality standards are reached, the status of operation and management funds, the rationality and degree of advancement of the management team structure, the adaptability and rationality of the water conservancy project management system, the degree of automatization and informationization of the management techniques, and the conduciveness of the exterior environment. The weights for evaluation indices were obtained through the analytic hierarchy process method with consideration of the difference between public welfare and profit-oriented water conservancy projects. This study provides a scientific method for evaluating the positive operation of water conservancy projects. 展开更多
关键词 water conservancy project positive operation evaluation index system analytic hierarchy process WEIGHT
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Reliability Analysis of a Cold Standby Repairable System with Repairman Extra Work 被引量:14
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作者 ZHANG Xin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第5期1015-1032,共18页
This paper deals with a cold standby repairman who can do extra work in idle time. The repairable system with two identical units and one authors are devoted to studying the unique existence and exponential stability ... This paper deals with a cold standby repairman who can do extra work in idle time. The repairable system with two identical units and one authors are devoted to studying the unique existence and exponential stability of the system solution. C0-semigroup theory is used to prove the existence of a unique nonnegative time-dependent solution of the system. Then by using the theory of resolvent positive operator, the authors derive that dynamic solution of the system exponentially converges to its steady-state one which is the eigenfunction corresponding to eigenvalue 0 of the system operator. Some reliability indices of the system are discussed with a different method from traditional one. The authors also make a profit analysis to determine the optimal service time outside the system to maximize the system profit. 展开更多
关键词 C0-SEMIGROUP exponential stability repairable system resolvent positive operator.
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EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTIONS TO A CLASS OF SEMILINEAR ELLIPTIC SYSTEMS 被引量:9
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作者 钟金标 陈祖墀 《Acta Mathematica Scientia》 SCIE CSCD 2002年第4期451-458,共8页
In this paper an existence and uniqueness theorem of positive solutions to a class of semilinear elliptic systems is proved. Also, a necessary condition for the existence of the positive solution is obtained. As the a... In this paper an existence and uniqueness theorem of positive solutions to a class of semilinear elliptic systems is proved. Also, a necessary condition for the existence of the positive solution is obtained. As the application of the main theorem, two examples are given. 展开更多
关键词 positive solution semilinear elliptic system compact and positive operator
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Operator Matrix Forms of Positive Operators 被引量:4
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作者 杜鸿科 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第4期9-12,共4页
If a 3-tuple (A:H_1→H_1,B:H_2→H_1,C:H_2→H_2) of operators on Hilbert spaces is given,we proved that the operator A:= on H=H_1⊕H_2 is≥0 if and only if A≥0,R(B) R(A1/2)and C≥B~* A^+ B, where A^+ is the generalize... If a 3-tuple (A:H_1→H_1,B:H_2→H_1,C:H_2→H_2) of operators on Hilbert spaces is given,we proved that the operator A:= on H=H_1⊕H_2 is≥0 if and only if A≥0,R(B) R(A1/2)and C≥B~* A^+ B, where A^+ is the generalized inverse of A. In general,A^+ is a closed operator,but since R(B) R(A1/2),B~* A^+ B is bounded yet. 展开更多
关键词 positive operator range of operator
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THE RELATION BETWEEN SIGN-CHANGING SOLUTION AND POSITIVE-NEGATIVE SOLUTIONS FOR NONLINEAR OPERATOR EQUATIONS AND ITS APPLICATIONS 被引量:1
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作者 张克梅 孙经先 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期463-468,共6页
By fixed point index theory and a result obtained by Amann, existence of the solution for a class of nonlinear operator equations x = Ax is discussed. Under suitable conditions, a couple of positive and negative solut... By fixed point index theory and a result obtained by Amann, existence of the solution for a class of nonlinear operator equations x = Ax is discussed. Under suitable conditions, a couple of positive and negative solutions are obtained. Finally, the abstract result is applied to nonlinear Sturm-Liouville boundary value problem, and at least four distinct solutions are obtained. 展开更多
关键词 CONE fixed point index theory uniformly positive operator.
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ASYMPTOTIC APPROXIMATION OF FUNCTIONS AND THEIR DERIVATIVES BY GENERALIZED BASKAKOV-SZAZS-DURRMEYER OPERATORS 被引量:1
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作者 Ulrich Abel Vijay Gupta Mircea Ivan 《Analysis in Theory and Applications》 2005年第1期15-26,共12页
We present the complete asymptotic expansion for a generalization of the Baskakov-Szasz-Durrmeyer operators and their derivatives.
关键词 approximation by positive operators rate of convergence degree of approximation asymptotic expansion Stirling numbers
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On the Method of Multiplier-enlargement and Approximation of Unbounded Continuous Functions 被引量:1
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作者 郑成德 王仁宏 《Northeastern Mathematical Journal》 CSCD 2001年第2期231-235,共5页
By combining the classical appropriate functions “1, x, x 2” with the method of multiplier enlargement, this paper establishes a theorem to approximate any unbounded continuous functions with modified positive... By combining the classical appropriate functions “1, x, x 2” with the method of multiplier enlargement, this paper establishes a theorem to approximate any unbounded continuous functions with modified positive linear operators. As an example, Hermite Fejér interpolation polynomial operators are analysed and studied, and a general conclusion is obtained. 展开更多
关键词 positive linear operator approximation of unbounded continuous function method of multiplier enlargement Hermite Fejér interpolation polynomial operator
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The Spectrum of Positive Operators on Hilbert Lattices
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作者 DENG Chun-yuan DU Hong-ke 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期52-56,共5页
Some spectral characterizations of positive operators on Hilbert lattices are presented. The application of these results can yield some equivalent relations of an irreducible positive operator. Some related results f... Some spectral characterizations of positive operators on Hilbert lattices are presented. The application of these results can yield some equivalent relations of an irreducible positive operator. Some related results for positive operators on Hilbert lattice are also obtained. 展开更多
关键词 Hilbert lattice positive operator IDEAL IRREDUCIBLE OPERATOR
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Remote interactions on two distributed quantum systems:nonlocal unambiguous quantum-state discrimination
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作者 陈立冰 金锐博 路洪 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期778-784,共7页
Remote quantum-state discrimination is a critical step for the implementation of quantum communication network and distributed quantum computation. We present a protocol for remotely implementing the unambiguous discr... Remote quantum-state discrimination is a critical step for the implementation of quantum communication network and distributed quantum computation. We present a protocol for remotely implementing the unambiguous discrimination between nonorthogonal states using quantum entanglements, local operations, and classical communications. This protocol consists of a remote generalized measurement described by a positive operator valued measurement (POVM). We explicitly construct the required remote POVM. The remote POVM can be realized by performing a nonlocal controlled-rotation operation on two spatially separated qubits, one is an ancillary qubit and the other is the qubit which is encoded by two nonorthogonal states to be distinguished, and a conventional local Von Neumann orthogonal measurement on the ancilla. The particular pair of states that can be remotely and unambiguously distinguished is specified by the state of the ancilla. The probability of successful discrimination is not optimal for all admissible pairs. However, for some subset it can be very close to an optimal value in an ordinary local POVM. 展开更多
关键词 remote quantum-state discrimination positive operator valued measure nonlocal controlled-rotation ENTANGLEMENT
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Teleporting a quantum controlled-Not with one target/two targets gate using two partially entangled states
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作者 陈立冰 金锐博 路洪 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期30-34,共5页
This paper considers the teleportation of quantum controlled-Not (CNOT) gate by using partially entangled states. Different from the known probability schemes, it presents a method for teleporting a CNOT gate with u... This paper considers the teleportation of quantum controlled-Not (CNOT) gate by using partially entangled states. Different from the known probability schemes, it presents a method for teleporting a CNOT gate with unit fidelity and unit probability by using two partially entangled pairs as quantum channel. The method is applicable to any two partially entangled pairs satisfying the condition that their smaller Schmidt coefficients μ and ν are (2μ + 2ν - 2μν - 1) ≥ 0. In this scheme, the sender's local generalized measurement described by a positive operator valued measurement (POVM) lies at the heart. It constructs the required POVM. It also puts forward a scheme for teleporting a CNOT with two targets gate with unit fidelity by using same quantum channel. With assistance of local operations and classical communications, three spatially separated users are able to complete the teleportation of a CNOT with two targets gate with probability of (2μ + 2ν - 1). With a proper value of μ and ν, the probability could reach nearly 1. 展开更多
关键词 partially entangled state TELEPORTATION CNOT gate positive operator valued measurement
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AN ORDER PRESERVING INEQUALITY FOR THREE OPERATORS VIA FURUTA INEQUALITY
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作者 杨长森 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期998-1002,共5页
Furuta showed that if A≥B≥0,then for each r≥0,f(p)=(A^r/2 B^p A^r/2)^t+r/p+r is decreasing for p≥t≥0.Using this result,the following inequality(C^r/2(AB^2A)^δC^ r/2)^ p-1+r/4δ+r ≤C^p-1+r is obtain... Furuta showed that if A≥B≥0,then for each r≥0,f(p)=(A^r/2 B^p A^r/2)^t+r/p+r is decreasing for p≥t≥0.Using this result,the following inequality(C^r/2(AB^2A)^δC^ r/2)^ p-1+r/4δ+r ≤C^p-1+r is obtained for 0〈p ≤1,r≥1,1/4≤δ≤1 and three positive operators A, B, C satisfy(A^1/2BA^1/2)^p/2≤A^p,(B^1/2AB^1/2)^p/2≥B^p,(C^1/2AC^1/2)^p/2≤C^p,(A^1/2CA^1/2)^p/2≥A^p. 展开更多
关键词 Positive operator Furuta inequality operator inequality
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MEAN CONVERGENCE OF SOME POSITIVE OPERATORS
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作者 史应光 《Acta Mathematica Scientia》 SCIE CSCD 1995年第2期136-143,共8页
L'convergence with 0<p<infinity of the positive operators F.(da,f) and G.(da,f), introduced by Nevai P. [3], and Qn,8(da,f), introduced by Hermann T. and Vertesi P. [1] to f is an element of C[-1,1] is prove... L'convergence with 0<p<infinity of the positive operators F.(da,f) and G.(da,f), introduced by Nevai P. [3], and Qn,8(da,f), introduced by Hermann T. and Vertesi P. [1] to f is an element of C[-1,1] is proved to hold for very general measures. 展开更多
关键词 POSITIVE OPERATORS MEAN CONVERGENCE ORTHOGONAL POLYNOMIALS
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A Note on Generalized Aluthge Transformation for p-hyponormal and Log-hyponormal Operators
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作者 DAI Hui-ya YANG Chang-sen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期525-532,共8页
We shall give some results on generalized aluthge transformation for phyponormal and log-hyponormal operators. We shall also discuss the best possibility of these results.
关键词 positive operator Furuta inequality Aluthge transformation best possibility
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ON THE TRANSPORT EQUATION WITH INTEGRAL BOUNDARY CONDITIONS AND ITS CONSERVAIVE LAW
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作者 ZHANG XIANWEN LIANG BENZHONG Department of Mathematics, Xinyang Teacher’s College, Xinyang 464000 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第1期33-42,共10页
The well-posedness for the time-dependent neutron transport equationwith integral boundary conditions is established in L^1 space. Some spectral propertiesof the transport operator are discussed, the dominant eigenval... The well-posedness for the time-dependent neutron transport equationwith integral boundary conditions is established in L^1 space. Some spectral propertiesof the transport operator are discussed, the dominant eigenvalue is proved existing,and furthermore, the conservative law of migrating particle numbers is established. 展开更多
关键词 Transport equation resolvent positive operator dominant eigenvalue stochastic C_0-semigroup.
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Dynamical time versus system time in quantum mechanics
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作者 Duan Arsenovi Nikola Buri +1 位作者 Dragomir Davidovi Slobodan Prvanovi 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期101-107,共7页
Properties of an operator representing the dynamical time in the extended parameterization invariant formulation of quantum mechanics are studied. It is shown that this time operator is given by a positive operator me... Properties of an operator representing the dynamical time in the extended parameterization invariant formulation of quantum mechanics are studied. It is shown that this time operator is given by a positive operator measure analogously to the quantities that are known to represent various measurable time operators. The relation between the dynamical time of the extended formulation and the best known example of the system time operator, i.e., for the free one- dimensional particle, is obtained. 展开更多
关键词 time operators extended state space positive operator valued measure
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An application of Furuta inequality and its best possibility
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作者 YANG Chang-sen DAI Hui-ya 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第3期326-330,共5页
This paper shows the best possibility for outer exponents of some inequalities under some conditions, and a counter example is obtained.
关键词 positive operator Furuta inequality operator inequality best possibility
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Multi-Attribute Selection Procedures Based on Regret and Rejoice for the Decision-Maker
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作者 Hanan Abdullah Mengash Manel Farouk Ayadi 《Computers, Materials & Continua》 SCIE EI 2022年第2期2777-2795,共19页
Feelings influence human beings’decision-making;therefore,incorporation of feeling factors in decision-making is very important.Regret and rejoice are very important emotional feelings that can have a great impact on... Feelings influence human beings’decision-making;therefore,incorporation of feeling factors in decision-making is very important.Regret and rejoice are very important emotional feelings that can have a great impact on decision-making if they are considered together.While regret has received most of the attention in related research,rejoice has been less considered even though it can greatly influence people’s preferences in decision-making.Furthermore,systematically incorporating regret and rejoice in the multicriteria decision-making(MCDM)modeling frameworks for decision-making has received little research attention.In this paper,we introduce a new multiattribute selection procedure that incorporates both regret and rejoice to select the best choice.We utilize the positional advantage operator concept to develop regret and rejoice mathematical equations,and prove them.The proposed MCDM procedure that incorporates these two emotional factors offers a decision-maker the flexibility to trade off some benefits in order to gain a state of psychological satisfaction.More specifically,regret and rejoice are presentedmathematically to enable the decision-maker to determine the values of regret and rejoice,and then make the decision in which the rejoice value is higher than the regret value.To test the performance of this new procedure,we apply it to three numerical examples proposed in previous works.The results are matched with those obtained by other methods such as the regret model,VIKOR,PROMETHEE I,and PROMETHEE II,thereby proving the efficacy of the new procedure. 展开更多
关键词 Multi-criteria decision-making positional advantage operator REGRET rejoice
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