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THE ABSENCE OF SINGULAR CONTINUOUS SPECTRUM FOR PERTURBED JACOBI OPERATORS
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作者 傅钲淇 黎雄 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期515-531,共17页
This paper is mainly about the spectral properties of a class of Jacobi operators(H_(c,b)u)(n)=c_(n)u(n+1)+c_(n-1)u(n-1)+b_(n)u(n),.where∣c_(n)−1∣=O(n^(−α))and b_(n)=O(n^(−1)).We will show that,forα≥1,the singula... This paper is mainly about the spectral properties of a class of Jacobi operators(H_(c,b)u)(n)=c_(n)u(n+1)+c_(n-1)u(n-1)+b_(n)u(n),.where∣c_(n)−1∣=O(n^(−α))and b_(n)=O(n^(−1)).We will show that,forα≥1,the singular continuous spectrum of the operator is empty. 展开更多
关键词 Jacobi operator singular continuous spectrum Prüfer variables
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The Continuous Wavelet Transform Associated with a Dunkl Type Operator on the Real Line
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作者 E. A. Al Zahrani M. A. Mourou 《Advances in Pure Mathematics》 2013年第5期443-450,共8页
We consider a singular differential-difference operator Λ on R which includes as a particular case the one-dimensional Dunkl operator. By using harmonic analysis tools corresponding to Λ, we introduce and study a ne... We consider a singular differential-difference operator Λ on R which includes as a particular case the one-dimensional Dunkl operator. By using harmonic analysis tools corresponding to Λ, we introduce and study a new continuous wavelet transform on R tied to Λ. Such a wavelet transform is exploited to invert an intertwining operator between Λ and the first derivative operator d/dx. 展开更多
关键词 Differential-Difference operator GENERALIZED WAVELETS GENERALIZED continuous WAVELET TRANSFORM
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Continuous query scheduler based on operators clustering
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作者 M.Sami Soliman 谭冠政 《Journal of Central South University》 SCIE EI CAS 2011年第3期782-790,共9页
Data stream management system (DSMS) provides convenient solutions to the problem of processing continuous queries on data streams.Previous approaches for scheduling these queries and their operators assume that each ... Data stream management system (DSMS) provides convenient solutions to the problem of processing continuous queries on data streams.Previous approaches for scheduling these queries and their operators assume that each operator runs in separate thread or all operators combine in one query plan and run in a single thread.Both approaches suffer from severe drawbacks concerning the thread overhead and the stalls due to expensive operators.To overcome these drawbacks,a novel approach called clustered operators scheduling (COS) is proposed that adaptively clusters operators of the query plan into a number of groups based on their selectivity and computing cost using S-mean clustering.Experimental evaluation is provided to demonstrate the potential benefits of COS scheduling over the other scheduling strategies.COS can provide adaptive,flexible,reliable,scalable and robust design for continuous query processor. 展开更多
关键词 data stream management systems operators scheduling continuous query CLUSTERING
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Continuous Multipartite Entangled Representation and Its Wigner Operator and Marginal Distribution
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作者 YUAN Hong-Chun LI Heng-Mei QI Kai-Guo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期1015-1020,共6页
By extending the EPR bipartite entanglement to multipartite case, we briefly introduce a continuous multipartite entangled representation and its canonical conjugate state in the multi-mode Fock space, analyze their S... By extending the EPR bipartite entanglement to multipartite case, we briefly introduce a continuous multipartite entangled representation and its canonical conjugate state in the multi-mode Fock space, analyze their Schmidt decompositions and give their entangling operators. Furthermore, based on the above analysis we also find the n-mode Wigner operator. In doing so we may identify the physical meaning of the marginal distribution of the Wigner function. 展开更多
关键词 continuous multipartite entangled representation Wigner operator marginal distribution
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Structure of continuous matrix product operator for transverse field Ising model:An analytic and numerical study
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作者 Yueshui Zhang Lei Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期121-142,共22页
We study the structure of the continuous matrix product operator(cMPO)^([1]) for the transverse field Ising model(TFIM).We prove TFIM’s cMPO is solvable and has the form T=e^(-1/2H_(F)).H_(F) is a non-local free ferm... We study the structure of the continuous matrix product operator(cMPO)^([1]) for the transverse field Ising model(TFIM).We prove TFIM’s cMPO is solvable and has the form T=e^(-1/2H_(F)).H_(F) is a non-local free fermionic Hamiltonian on a ring with circumferenceβ,whose ground state is gapped and non-degenerate even at the critical point.The full spectrum of H_(F) is determined analytically.At the critical point,our results verify the state–operator-correspondence^([2]) in the conformal field theory(CFT).We also design a numerical algorithm based on Bloch state ansatz to calculate the lowlying excited states of general(Hermitian)cMPO.Our numerical calculations coincide with the analytic results of TFIM.In the end,we give a short discussion about the entanglement entropy of cMPO’s ground state. 展开更多
关键词 continuous matrix product operator transverse field Ising model state-operator-correspondence
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Regularity of Continuous Linear Operators on Banach Function Spaces
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作者 JIANGNian-shengt ChenZi-li 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第1期51-56,共6页
In this paper we present some characterizations of Banach function spaces on which every continuous linear operator is regular.
关键词 Banach function space continuous linear operator REGULAR
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The Representation of Continuous Linear Operator by Integral
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作者 曾韧英 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第3期41-44, ,共4页
In this paper,we study the representation of linear operator on but abandom the Radon-Nikodym property and give a necessary and sufficient condition for representability of linear operator on by integral.
关键词 Frechet space μ-integral continuous linear operator
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Semigroup of Weakly Continuous Operators Associated to a Generalized Schrödinger Equation
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作者 Yolanda Silvia Santiago Ayala 《Journal of Applied Mathematics and Physics》 2023年第4期1061-1076,共16页
In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger equation in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously r... In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger equation in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously respect to the initial data in P’. Introducing a family of weakly continuous operators, we prove that this family is a semigroup of operators in P’. Then, with this family of operators, we get a fine version of the existence and dependency continuous theorem obtained. Finally, we provide some consequences of this study. 展开更多
关键词 Semigroups Theory Weakly continuous operators Existence of Solution Generalized Schrödinger Equation Distributional Problem Periodic Distributional Space
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Group of Weakly Continuous Operators Associated to a Generalized Schrödinger Type Homogeneous Model
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作者 Yolanda Silvia Santiago Ayala 《Journal of Applied Mathematics and Physics》 2023年第4期919-932,共14页
In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger type homogeneous model in the periodic distributional space P’. Furthermore, we prove that the solution depends ... In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger type homogeneous model in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously respect to the initial data in P’. Introducing a family of weakly continuous operators, we prove that this family is a group of operators in P’. Then, with this family of operators, we get a fine version of the existence and dependency continuous theorem obtained. Finally, we give some remarks derived from this study. 展开更多
关键词 Groups Theory Weakly continuous operators Existence of Solution Generalized Schrödinger Type Equation Homogeneous Equation Periodic Distributional Space
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Effects of operating parameters on the flow field in slab continuous casting molds with narrow widths 被引量:10
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作者 Tao Zhang Jian Yang +3 位作者 Gang-jun Xu Hong-jun Liu Jun-jun Zhou Wei Qin 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第2期238-248,共11页
Computational simulations and high-temperature measurements of velocities near the surface of a mold were carried out by using the rod deflection method to study the effects of various operating parameters on the flow... Computational simulations and high-temperature measurements of velocities near the surface of a mold were carried out by using the rod deflection method to study the effects of various operating parameters on the flow field in slab continuous casting(CC)molds with narrow widths for the production of automobile exposed panels.Reasonable agreement between the calculated results and measured subsurface velocities of liquid steel was obtained under different operating parameters of the CC process.The simulation results reveal that the flow field in the horizontal plane located 50 mm from the meniscus can be used as the characteristic flow field to optimize the flow field of molten steel in the mold.Increases in casting speed can increase the subsurface velocity of molten steel and shift the position of the vortex core downward in the downward circulation zone.The flow field of liquid steel in a 1040 mm-wide slab CC mold can be improved by an Ar gas flow rate of 7 L·min^−1 and casting speed of 1.7 m·min^−1.Under the present experimental conditions,the double-roll flow pattern is generally stable at a submerged entry nozzle immersion depth of 170 mm. 展开更多
关键词 flow field rod deflection method continuous casting narrow width numerical simulation operating parameters
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Quantitative evaluation of multi-process collaborative operation in steelmaking–continuous casting sections 被引量:4
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作者 Jian-ping Yang Qing Liu +1 位作者 Wei-da Guo Jun-guo Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第8期1353-1366,共14页
The quantitative evaluation of multi-process collaborative operation is of great significance for the improvement of production planning and scheduling in steelmaking–continuous casting sections(SCCSs). However, this... The quantitative evaluation of multi-process collaborative operation is of great significance for the improvement of production planning and scheduling in steelmaking–continuous casting sections(SCCSs). However, this evaluation is difficult since it relies on an in-depth understanding of the operating mechanism of SCCSs, and few existing methods can be used to conduct the evaluation, due to the lack of full-scale consideration of the multiple factors related to the production operation. In this study, three quantitative models were developed, and the multiprocess collaborative operation level was evaluated through the laminar-flow operation degree, the process matching degree, and the scheduling strategy availability degree. Based on the evaluation models for the laminar-flow operation and process matching levels, this study investigated the production status of two steelmaking plants, plants A and B, based on actual production data. The average laminar-flow operation(process matching) degrees of SCCSs were obtained as 0.638(0.610) and 1.000(0.759) for plants A and B, respectively, for the period of April to July 2019. Then, a scheduling strategy based on the optimization of the furnace-caster coordinating mode was suggested for plant A. Simulation experiments showed higher availability than the greedy-based and manual strategies. After the proposed scheduling strategy was applied,the average process matching degree of the SCCS of plant A increased by 4.6% for the period of September to November 2019. The multi-process collaborative operation level was improved with fewer adjustments and interruptions in casting. 展开更多
关键词 steelmaking–continuous casting multi-process collaborative operation quantitative evaluation model laminar-flow operation process matching scheduling strategy
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Elements and Experiments of Shenzhen Continuous Operating Reference Stations (SZCORS) System 被引量:3
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作者 LUOHeping SHIXiaoyan LIUHui 《Geo-Spatial Information Science》 2005年第1期19-22,共4页
Real-time kinematic GPS precise positioning has been playing an increasing role in both surveying and navigation. Based on the city’s fibre LAN network, Shenzhen Continuous Operating Reference Stations (SZCORS) syste... Real-time kinematic GPS precise positioning has been playing an increasing role in both surveying and navigation. Based on the city’s fibre LAN network, Shenzhen Continuous Operating Reference Stations (SZCORS) system has been established and consists of GPS reference stations, system control center, user’s data center, and real-time datacom network. The SZCORS system provides users the real-time centimeter positioning or post-processing millimeter positioning. This paper makes discussion on the structure of SZCORS system. Some experiments have been made to test the usablity, and then the data has been analyzed. 展开更多
关键词 GPS continuous operating reference stations system virtual referencestation(VRS)
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L^p CONTINUITY OF HRMANDER SYMBOL OPERATORS OpS_(0,0) ~m AND NUMERICAL ALGORITHM
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作者 杨奇祥 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1517-1534,共18页
If we use Littlewood-Paley decomposition, there is no pseudo-orthogonality for Ho¨rmander symbol operators OpS m 0 , 0 , which is different to the case S m ρ,δ (0 ≤δ 〈 ρ≤ 1). In this paper, we use a spec... If we use Littlewood-Paley decomposition, there is no pseudo-orthogonality for Ho¨rmander symbol operators OpS m 0 , 0 , which is different to the case S m ρ,δ (0 ≤δ 〈 ρ≤ 1). In this paper, we use a special numerical algorithm based on wavelets to study the L p continuity of non infinite smooth operators OpS m 0 , 0 ; in fact, we apply first special wavelets to symbol to get special basic operators, then we regroup all the special basic operators at given scale and prove that such scale operator’s continuity decreases very fast, we sum such scale operators and a symbol operator can be approached by very good compact operators. By correlation of basic operators, we get very exact pseudo-orthogonality and also L 2 → L 2 continuity for scale operators. By considering the influence region of scale operator, we get H 1 (= F 0 , 2 1 ) → L 1 continuity and L ∞→ BMO continuity. By interpolation theorem, we get also L p (= F 0 , 2 p ) → L p continuity for 1 〈 p 〈 ∞ . Our results are sharp for F 0 , 2 p → L p continuity when 1 ≤ p ≤ 2, that is to say, we find out the exact order of derivations for which the symbols can ensure the resulting operators to be bounded on these spaces. 展开更多
关键词 Ho¨rmander symbol class wavelet and numerical algorithm basic operators and scale operators approximation by compact operator and operator’s continuity
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Continuous-variable quantum key distribution based on photon addition operation
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作者 Xiao-Ting Chen Lu-Ping Zhang +2 位作者 Shou-Kang Chang Huan Zhang Li-Yun Hu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期126-132,共7页
It is shown that the non-Gaussian operations can not only be used to prepare the nonclassical states, but also to improve the entanglement degree between Gaussian states. Thus these operations are naturally considered... It is shown that the non-Gaussian operations can not only be used to prepare the nonclassical states, but also to improve the entanglement degree between Gaussian states. Thus these operations are naturally considered to enhance the performance of continuous variable quantum key distribution(CVQKD), in which the non-Gaussian operations are usually placed on the right-side of the entangled source. Here we propose another scheme for further improving the performance of CVQKD with the entangled-based scheme by operating photon-addition operation on the left-side of the entangled source.It is found that the photon-addition operation on the left-side presents both higher success probability and better secure key rate and transmission distance than the photon subtraction on the right-side, although they share the same maximal tolerable noise. In addition, compared to both photon subtraction and photon addition on the right-side, our scheme shows the best performance and the photon addition on the right-side is the worst. 展开更多
关键词 non-Gaussian operations continuous variable quantum key distribution photon-addition operation
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Deterministic Quantum Secure Direct Communication with Dense Coding and Continuous Variable Operations
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作者 HAN Lian-Fang CHEN Yue-Ming YUAN Hao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期648-652,共5页
We propose a deterministic quantum secure direct two check photon sequences are used to check the securities of the communication protocol by using dense coding. The channels between the message sender and the receive... We propose a deterministic quantum secure direct two check photon sequences are used to check the securities of the communication protocol by using dense coding. The channels between the message sender and the receiver. The continuous variable operations instead of the usual discrete unitary operations are performed on the travel photons so that the security of the present protocol can be enhanced. Therefore some specific attacks such as denial-of-service attack, intercept-measure-resend attack and invisible photon attack can be prevented in ideal quantum channel. In addition, the scheme is still secure in noise channel. Furthurmore, this protocol has the advantage of high capacity and can be realized in the experiment. 展开更多
关键词 ping-pong protocol continuous variable operations quantum secure direct communication SECURITY capacity
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A continuous-time formulation for refinery production scheduling problems involving operational transitions in mode switching
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作者 Lei Shi Yongheng Jiang +1 位作者 Ling Wang Dexian Huang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第8期1020-1031,共12页
In the refinery scheduling, operational transitions in mode switching are of great significance to formulate dynamic nature of production and obtain efficient schedules. The discrete-time formulation meets two main ch... In the refinery scheduling, operational transitions in mode switching are of great significance to formulate dynamic nature of production and obtain efficient schedules. The discrete-time formulation meets two main challenges in modeling: discrete approximation of time and large size of mixed-integer linear problem(MILP).In this article, a continuous-time refinery scheduling model, which involves transitions of mode switching, is presented due to these challenges. To reduce the difficulty in solving large scale MILPs resulting from the sequencing constraints, the global event-based formulation is chosen. Both transition constraints and production transitions are introduced and the numbers of key variables and constraints in both of the discrete-time and continuous-time formulations are analyzed and compared. Three cases with different lengths of time horizons and different numbers of orders are studied to show the efficiency of the proposed model. 展开更多
关键词 REFINERY SCHEDULING operATIONAL TRANSITIONS continuous-TIME REPRESENTATION
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Tianwan sets a national record for continuous and safe operation in first fuel cycle
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《Electricity》 2008年第2期40-,共1页
On May 1st, China National Nuclear Corporation(CNNC) announced in Beijing that unit 1 and unit 2 ofTianwan Nuclear Power Plant cooperatively constructedby China and Russia have completed in succession thefirst fuel cy... On May 1st, China National Nuclear Corporation(CNNC) announced in Beijing that unit 1 and unit 2 ofTianwan Nuclear Power Plant cooperatively constructedby China and Russia have completed in succession thefirst fuel cycle operation continuously and safely. It is 展开更多
关键词 Tianwan sets a national record for continuous and safe operation in first fuel cycle
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EXACT CONTROLLABILITY AND CONTINUOUS DEPENDENCE OF FRACTIONAL NEUTRAL INTEGRO-DIFFERENTIAL EQUATIONS WITH STATE-DEPENDENT DELAY 被引量:17
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作者 马和平 刘斌 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期235-258,共24页
In the present paper,with the help of the resolvent operator and some analytic methods,the exact controllability and continuous dependence are investigated for a fractional neutral integro-differential equations with ... In the present paper,with the help of the resolvent operator and some analytic methods,the exact controllability and continuous dependence are investigated for a fractional neutral integro-differential equations with state-dependent delay.As an application,we also give one example to demonstrate our results. 展开更多
关键词 CONTROLLABILITY continuous dependence fractional neutral integro-differentialequations state-dependent delay resolvent operator
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Boundary properties for several singular integral operators in real Clifford analysis 被引量:7
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作者 YANG He-ju XIE Yong-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第3期349-358,共10页
On the basis of the Cauchy integral formulas for regular and biregular functions, we define some Cauchy-type singular integral operators. Then we discuss the Holder continuous property of some singular integral operat... On the basis of the Cauchy integral formulas for regular and biregular functions, we define some Cauchy-type singular integral operators. Then we discuss the Holder continuous property of some singular integral operators with one integral variable. Then we divide a singular integral operator with two variables into three parts and prove its Holder continuous property on the boundary. 展开更多
关键词 Singular integral operator Holder continuous function boundary property.
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Simulation of Continuous Esterification Process of Polyester Polyols 被引量:2
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作者 陈礼科 奚桢浩 +2 位作者 秦榛 赵玲 袁渭康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第3期246-252,共7页
Based on the kinetic and thermodynamic equations, a comprehensive mathematical model for the con- tinuous esterification process of polyester polyols was developed, which was carried out in an innovational bub- bling ... Based on the kinetic and thermodynamic equations, a comprehensive mathematical model for the con- tinuous esterification process of polyester polyols was developed, which was carried out in an innovational bub- bling reactive distillation tower (BRDT) at atmospheric pressure. In this new type of reactor, direct esterification between ethylene glycol and adipic acid was accomplished efficiently and rapidly. A bench BRDT with the height of 2 m was applied for the esteriflcation process of l^oly (ethylene adlpate) (P'EA). In the continuous operation, Hn- ear oligomers were discharged from the bottom of the column, while water passed a few column trays and a pack- ing section as a condensation byproduct. The influence of major operating conditions on reactor performance was also simulated. Simulation results were in good agreement with experimental data, providing a strategy for devel- oping and optimizing this process. 展开更多
关键词 poly (ethylene adipate) ESTERIFICATION continuous operation mathematical model reactive distillation
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