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A Nonlocal Operator Method for Partial Differential Equations with Application to Electromagnetic Waveguide Problem 被引量:38
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作者 Timon Rabczuk Huilong Ren Xiaoying Zhuang 《Computers, Materials & Continua》 SCIE EI 2019年第4期31-55,共25页
A novel nonlocal operator theory based on the variational principle is proposed for the solution of partial differential equations.Common differential operators as well as the variational forms are defined within the ... A novel nonlocal operator theory based on the variational principle is proposed for the solution of partial differential equations.Common differential operators as well as the variational forms are defined within the context of nonlocal operators.The present nonlocal formulation allows the assembling of the tangent stiffness matrix with ease and simplicity,which is necessary for the eigenvalue analysis such as the waveguide problem.The present formulation is applied to solve the differential electromagnetic vector wave equations based on electric fields.The governing equations are converted into nonlocal integral form.An hourglass energy functional is introduced for the elimination of zeroenergy modes.Finally,the proposed method is validated by testing three classical benchmark problems. 展开更多
关键词 Nonlocal operator method Variational principle Nonlocal operators Hourglass mode
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ADJOINT OPERATOR METHOD AND NORMAL FORMS OF HIGHER ORDER FOR NONLINEAR DYNAMICAL SYSTEM
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作者 张伟 陈予恕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第5期449-461,共13页
Normal form theory is a very effective method when we study degenerate bifurcations of nonlinear dynamical systems. In this paper by using adjoint operator method, normal forms of order 3 and 4 for nonlinear dynamical... Normal form theory is a very effective method when we study degenerate bifurcations of nonlinear dynamical systems. In this paper by using adjoint operator method, normal forms of order 3 and 4 for nonlinear dynamical system with nilpotent linear part and Z(2)-asymmetry are computed. According to normal forms obtained, universal unfoldings for some degenerate bifurcation cases of codimension 3 and simple global characterizations, are studied. 展开更多
关键词 nonlinear dynamical system adjoint operator method normal forms of order 3 and 4 degenerate bifurcation of codimension 3 universal unfolding
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Optical Operator Method in Two-Mode Case and Entangled Fresnel Operator's Decomposition
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作者 马善钧 胡利云 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期907-912,共6页
Based on the entangled Fresnel operator (EFO) proposed in [Commun. Theor. Phys. 46 (2006) 559], the optical operator method studied by the IWOP technique (Ma et al., Commun. Theor. Phys. 49 (2008) 1295) is ext... Based on the entangled Fresnel operator (EFO) proposed in [Commun. Theor. Phys. 46 (2006) 559], the optical operator method studied by the IWOP technique (Ma et al., Commun. Theor. Phys. 49 (2008) 1295) is extended to the two-mode case, which gives the decomposition of the entangled Fresnel operator, corresponding to the decomposition of ray transfer matrix [A, B, C, D]. The EFO can unify those optical operators in two-mode case. Various decompositions of EFO into the exponential canonical operators are obtained. The entangled state representation is useful in the research. 展开更多
关键词 optical operator method entangled Fresnel operator IWOP technique
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Optical Operator Method Studied via Fresnel Operator Decomposition and Coherent State Representation
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作者 MA Shan-Jun HU Li-Yun FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1295-1298,共4页
We find that the mapping from classical optical transformations to the optical operator method can be realized by using the coherent state representation and the technique of integration within an ordered product of o... We find that the mapping from classical optical transformations to the optical operator method can be realized by using the coherent state representation and the technique of integration within an ordered product of operators. The optical Fresnel operator derived in (Commun. Theor. Phys. (Beijing, China) 38 (2002) 147) can unify those frequently used optical operators. Various decompositions of Fresnel operator into the exponential canonical operators are obtained. 展开更多
关键词 optical operator method optical Fresnel operator IWOP technique
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No-core Monte Carlo shell model calculations with unitary correlation operator method and similarity renormalization group
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作者 刘朗 《Chinese Physics C》 SCIE CAS CSCD 2015年第5期28-32,共5页
The unitary correlation operator method (UCOM) and the similarity renormalization group theory (SRG) are compared and discussed in the framework of the no-core Monte Carlo shell model (MCSM) calculations for ^3H... The unitary correlation operator method (UCOM) and the similarity renormalization group theory (SRG) are compared and discussed in the framework of the no-core Monte Carlo shell model (MCSM) calculations for ^3H and ^4He. The treatment of spurious center-of-mass motion by Lawson's prescription is performed in the MCSM calculations. These results with both transformed interactions show good suppression of spurious center-of-mass motion with proper Lawson's prescription parameter βc.m. values. The UCOM potentials obtain faster convergence of total energy for the ground state than that of SRG potentials in the MCSM calculations, which differs from the cases in the no-core shell model calculations (NCSM). These differences are discussed and analyzed in terms of the truncation scheme in the MCSM and NCSM, as well as the properties of the potentials of SRG and UCOM. 展开更多
关键词 Monte Carlo shell model unitary correlation operator method similarity renormalization group theory
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ELEMENT FUNCTIONS OF DISCRETE OPERATOR DIFFERENCE METHOD
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作者 田中旭 唐立民 刘正兴 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第6期619-626,共8页
The discrete scheme called discrete operator difference for differential equations was given. Several difference elements for plate bending problems and plane problems were given. By investigating these elements, the ... The discrete scheme called discrete operator difference for differential equations was given. Several difference elements for plate bending problems and plane problems were given. By investigating these elements, the ability of the discrete forms expressing to the element functions was talked about. In discrete operator difference method, the displacements of the elements can be reproduced exactly in the discrete forms whether the displacements are conforming or not. According to this point, discrete operator difference method is a method with good performance. 展开更多
关键词 discrete operator difference method element function reproduce exactly
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Quantum mechanical operator realization of the Stirling numbers theory studied by virtue of the operator Hermite polynomials method
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作者 范洪义 楼森岳 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期102-105,共4页
Based on the operator Hermite polynomials method(OHPM), we study Stirling numbers in the context of quantum mechanics, i.e., we present operator realization of generating function formulas of Stirling numbers with s... Based on the operator Hermite polynomials method(OHPM), we study Stirling numbers in the context of quantum mechanics, i.e., we present operator realization of generating function formulas of Stirling numbers with some applications.As a by-product, we derive a summation formula involving both Stirling number and Hermite polynomials. 展开更多
关键词 operator Hermite polynomials method(OHPM) Stirling numbers
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The Operator Splitting Method for Black-Scholes Equation
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作者 Yassir Daoud Turgut Ozis 《Applied Mathematics》 2011年第6期771-778,共8页
The Operator Splitting method is applied to differential equations occurring as mathematical models in financial models. This paper provides various operator splitting methods to obtain an effective and accurate solut... The Operator Splitting method is applied to differential equations occurring as mathematical models in financial models. This paper provides various operator splitting methods to obtain an effective and accurate solution to the Black-Scholes equation with appropriate boundary conditions for a European option pricing problem. Finally brief comparisons of option prices are given by different models. 展开更多
关键词 operator Splitting method Black-Scholes Equation European Option Pricing
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Satellite remote sensing of sea-ice and its operational monitoring method along the coast of China 被引量:3
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作者 Gong Jialong National Marine Environment Forecasting Center, SOA, Beijing. China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第3期379-390,共12页
Sea-ice is an important operational item for real timely monitoring and forecasting marine environment of China. This paper introduces an operational method of satellite remote sensing to monitor sea- ice using quanti... Sea-ice is an important operational item for real timely monitoring and forecasting marine environment of China. This paper introduces an operational method of satellite remote sensing to monitor sea- ice using quantitative data of NOAA, and its contents include computer processing of AVHRR sounding data of NOAA and its program design, imagery processing of sea-ice imagery from satellite and their thematic analysis. The sea-ice satellite colour imageries processed via this software system are able to interpret sea-ice pattern, characterizing it by thickness, maximum position of ice boundary, floe concentration and dynamic process of ice changing. At the same time, analyses of the ice condition of the Bohai Sea for the two-year period (1986-1988) as monitored by satellite have been summarized. 展开更多
关键词 In Satellite remote sensing of sea-ice and its operational monitoring method along the coast of China
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Choice of operative method for pancreaticojejunostomy and a multivariable study of pancreatic leakage in pancreaticoduodenectomy 被引量:1
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作者 Hui Liang Jian-Guo Wu +4 位作者 Fei Wang Bo-Xuan Chen Shi-Tian Zou Cong Wang Shuai-Wu Luo 《World Journal of Gastrointestinal Surgery》 SCIE 2021年第11期1405-1413,共9页
BACKGROUND As one of the major abdominal operations,pancreaticoduodenectomy(PD)involves many organs.The operation is complex,and the scope of the operation is large,which can cause significant trauma in patients.The o... BACKGROUND As one of the major abdominal operations,pancreaticoduodenectomy(PD)involves many organs.The operation is complex,and the scope of the operation is large,which can cause significant trauma in patients.The operation has a high rate of complications.Pancreatic leakage is the main complication after PD.When pancreatic leakage occurs after PD,it can often lead to abdominal bleeding and infection,threatening the lives of patients.One study found that pancreatic leakage was affected by many factors including the choice of pancreaticojejunostomy method which can be well controlled.AIM To investigate the choice of operative methods for pancreaticojejunostomy and to conduct a multivariate study of pancreatic leakage in PD.METHODS A total of 420 patients undergoing PD in our hospital from January 2014 to March 2019 were enrolled and divided into group A(n=198)and group B(n=222)according to the pancreatointestinal anastomosis method adopted during the operation.Duct-to-mucosa pancreatojejunostomy was performed in group A and bundled pancreaticojejunostomy was performed in group B.The operation time,intraoperative blood loss,and pancreatic leakage of the two groups were assessed.The occurrence of pancreatic leakage after the operation in different patients was analyzed.RESULTS The differences in operative time and intraoperative bleeding between groups A and B were not significant(P>0.05).In group A,the time of pancreatojejunostomy was 26.03±4.40 min and pancreatic duct diameter was 3.90±1.10 mm.These measurements were significantly higher than those in group B(P<0.05).The differences in the occurrence of pancreatic leakage,abdominal infection,abdominal hemorrhage and gastric retention between group A and group B were not significant(P>0.05).The rates of pancreatic leakage in patients with preoperative albumin<30 g/L,preoperative jaundice time≥8 wk,and pancreatic duct diameter<3 mm,were 23.33%,33.96%,and 19.01%,respectively.These were significantly higher than those in patients with preoperative albumin≥30 g/L,preoperative jaundice time<8 wk,and pancreatic duct diameter≥3 cm(P<0.05).Logistic regression analysis showed that preoperative albumin<30 g/L,preoperative jaundice time≥8 wk,and pancreatic duct diameter<3 mm were risk factors for pancreatic leakage after PD(odds ratio=2.038,2.416 and 2.670,P<0.05).CONCLUSION The pancreatointestinal anastomosis method during PD has no significant effect on the occurrence of pancreatic leakage.The main risk factors for pancreatic leakage include preoperative albumin,preoperative jaundice time,and pancreatic duct diameter. 展开更多
关键词 PANCREATODUODENECTOMY Pancreatojejunostomy Choice of operative methods Pancreatic leakage Multivariate analysis
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Efficient hybrid method for time reversal superresolution imaging 被引量:1
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作者 Xiaohua Wang Wei Gao Bingzhong Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期32-37,共6页
An efficient hybrid time reversal(TR) imaging method based on signal subspace and noise subspace is proposed for electromagnetic superresolution detecting and imaging. First, the locations of targets are estimated b... An efficient hybrid time reversal(TR) imaging method based on signal subspace and noise subspace is proposed for electromagnetic superresolution detecting and imaging. First, the locations of targets are estimated by the transmitting-mode decomposition of the TR operator(DORT) method employing the signal subspace. Then, the TR multiple signal classification(TR-MUSIC)method employing the noise subspace is used in the estimated target area to get the superresolution imaging of targets. Two examples with homogeneous and inhomogeneous background mediums are considered, respectively. The results show that the proposed hybrid method has advantages in CPU time and memory cost because of the combination of rough and fine imaging. 展开更多
关键词 time reversal(TR) decomposition of the time-reversal operator(DORT) method multiple signal classification(MUSIC) method SUPERRESOLUTION IMAGING
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Uncertain optimal model and solving method to platform scheduling problem in battlefield 被引量:2
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作者 Yu Sun Peiyang Yao +1 位作者 Dongdong Shui Jieyong Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期157-165,共9页
The platform scheduling problem in battlefield is one of the important problems in military operational research.It needs to minimize mission completing time and meanwhile maximize the mission completing accuracy with... The platform scheduling problem in battlefield is one of the important problems in military operational research.It needs to minimize mission completing time and meanwhile maximize the mission completing accuracy with a limited number of platforms.Though the traditional certain models obtain some good results,uncertain model is still needed to be introduced since the battlefield environment is complex and unstable.An uncertain model is prposed for the platform scheduling problem.Related parameters in this model are set to be fuzzy or stochastic.Due to the inherent disadvantage of the solving methods for traditional models,a new method is proposed to solve the uncertain model.Finally,the practicability and availability of the proposed method are demonstrated with a case of joint campaign. 展开更多
关键词 operational research platform scheduling uncertain model solving method.
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Operator health risk evaluation of off-highway dump truck under shovel loading condition 被引量:1
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作者 申焱华 许敏 +2 位作者 金纯 高玉 魏福林 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2655-2664,共10页
To evaluate the operator health risk exposed to whole-body vibration(WBV) while the electric-shovel loads the ore on the truck body, the semi-truck mathematical model and 3-D virtual prototype were built to simulate t... To evaluate the operator health risk exposed to whole-body vibration(WBV) while the electric-shovel loads the ore on the truck body, the semi-truck mathematical model and 3-D virtual prototype were built to simulate the high shockwave of truck cab under the shovel loading. Discrete element method was utilized to accurately estimate the impacting force on the truck body. Based on the ISO 2631-5 criteria, the Sed is about 0.56 MPa in both models, which means that the dump operators have a high probability of adverse health effects over long-term exposure to these vibrations. The 4-DOF operator model was built to investigate the biodynamic response of seated-human body exposed to WBV in terms of the transmission of vibrations through the body. The results show that the response peak is in the frequency range of 4-6 Hz corresponding to the primary body resonant frequency. 展开更多
关键词 dump truck loading operation impacting force discrete element method
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Operational Methods for Ships in Waves From Perspectives of Structure Health and Maneuvering Convenience
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作者 ZHOU Feng ZHOU Junwei +1 位作者 CHEN Yuli WANG Deling 《Journal of Shipping and Ocean Engineering》 2017年第3期100-107,共8页
Based on the stress-strain data collected by a CSSMAS (container ship structure monitoring and analyzing system) onboard a container vessel, stress-strain responses of the ship's structure in high wave were analyze... Based on the stress-strain data collected by a CSSMAS (container ship structure monitoring and analyzing system) onboard a container vessel, stress-strain responses of the ship's structure in high wave were analyzed and illustrated for the identification of reasonable safe course sections. Besides the ship's structure safety, the maneuvering convenience is also deemed as a main concern which influences the safety of vessels in heavy waves. In order to develop a comprehensive guidance in adverse weather condition, the basic requirements on maneuvering convenience for vessels in storm were further discussed. In combination of the two requirements, namely structure health and maneuvering convenience, a proposed operational method was thus developed, which was an amendment to the traditional navigational method for ship in extreme weather. At the end of this paper, an example of optimal course planning in bad weather was illustrated by using the operational method proposed. 展开更多
关键词 Structural health maneuvering convenience extreme weather operational method
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Research on Controlled Volume Operation Method of Large-scale Water Transfer Canal
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作者 DING Zhiliang WANG Changde +1 位作者 XU Duo XIAO Hua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期47-59,共13页
The controlled volume method of operation is especially suitable for large-scale water delivery canal system with complex operation requirements. An operating simulation model based on the storage volume control metho... The controlled volume method of operation is especially suitable for large-scale water delivery canal system with complex operation requirements. An operating simulation model based on the storage volume control method for multi-reach canal system in series was established. In allusion to the deficiency of existing controlled volume algorithm, the improved controlled volume algorithm of the whole canal pools was proposed, and the simulation results indicated that the storage volume and water level of each canal pool could be accurately controlled after the improved algorithm had been adopted. However, for some typical discharge demand operating conditions, if the previously mentioned algorithm was adopted, then it certainly would cause some unnecessary gate adjustments, and consequently the disturbed canal pools would be increased. Therefore, the idea of controlled volume operation method of continuous canal pools was proposed, and corresponding algorithm was designed. Through simulating practical project, the results indicated that the new controlled volume algorithm proposed for typical operating conditions could comparatively and obviously reduce the number of regulated check gates and disturb canal pools for some typical discharge demand operating conditions, thus the control efficiency of canal system could be improved. 展开更多
关键词 canal operation controlled volume method of operation control algorithm SIMULATION
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Recast combination functions of coordinate and momentum operators into their ordered product forms
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作者 Lei Wang Xiang-Guo Meng Ji-Suo Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第5期85-91,共7页
By using the parameter differential method of operators,we recast the combination function of coordinate and momentum operators into its normal and anti-normal orderings,which is more ecumenical,simpler,and neater tha... By using the parameter differential method of operators,we recast the combination function of coordinate and momentum operators into its normal and anti-normal orderings,which is more ecumenical,simpler,and neater than the existing ways.These products are very useful in obtaining some new differential relations and useful mathematical integral formulas.Further,we derive the normally ordered form of the operator(fQ+gP)^-n with n being an arbitrary positive integer by using the parameter tracing method of operators together with the intermediate coordinate-momentum representation.In addition,general mutual transformation rules of the normal and anti-normal orderings,which have good universality,are derived and hence the anti-normal ordering of(fQ+gP)^-n is also obtained.Finally,the application of some new identities is given. 展开更多
关键词 normal and anti-normal orderings parameter differential method of operators intermediate coordinate-momentum representation
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Multi-Waves,Breathers,Periodic and Cross-Kink Solutions to the(2+1)-Dimensional Variable-Coefficient Caudrey-Dodd-Gibbon-Kotera-Sawada Equation
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作者 LIU Dong JU Xiaodong +2 位作者 ILHAN Onur Alp MANAFIAN Jalil ISMAEL Hajar Farhan 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第1期35-44,共10页
The present article deals with multi-waves and breathers solution of the(2+1)-dimensional variable-coefficient CaudreyDodd-Gibbon-Kotera-Sawada equation under the Hirota bilinear operator method.The obtained solutions... The present article deals with multi-waves and breathers solution of the(2+1)-dimensional variable-coefficient CaudreyDodd-Gibbon-Kotera-Sawada equation under the Hirota bilinear operator method.The obtained solutions for solving the current equation represent some localized waves including soliton,solitary wave solutions,periodic and cross-kink solutions in which have been investigated by the approach of the bilinear method.Mainly,by choosing specific parameter constraints in the multi-waves and breathers,all cases the periodic and cross-kink solutions can be captured from the 1-and 2-soliton.The obtained solutions are extended with numerical simulation to analyze graphically,which results in 1-and 2-soliton solutions and also periodic and cross-kink solutions profiles.That will be extensively used to report many attractive physical phenomena in the fields of acoustics,heat transfer,fluid dynamics,classical mechanics,and so on.We have shown that the assigned method is further general,efficient,straightforward,and powerful and can be exerted to establish exact solutions of diverse kinds of fractional equations originated in mathematical physics and engineering.We have depicted the figures of the evaluated solutions in order to interpret the physical phenomena. 展开更多
关键词 variable-coefficient Caudrey-Dodd-Gibbon-Kotera-Sawada equation Hirota bilinear operator method soliton multi-waves and breathers periodic and cross-kink solitray wave solutions
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Non-Markovian dynamics of two non-coupled qubits interacting with two separate reservoirs with different spectral densities
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作者 王小云 丁邦福 赵鹤平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期128-132,共5页
The dynamics of two non-coupled qubits independently interacting with their reservoirs is solved by the time convolutionless projection operator method. We study two-qubit quantum correlation dynamics for two differen... The dynamics of two non-coupled qubits independently interacting with their reservoirs is solved by the time convolutionless projection operator method. We study two-qubit quantum correlation dynamics for two different types of spectral densities, which are a Lorentzian distribution and an Ohmic spectral density with a Lorentzian–Drude cutoff function. For two qubits initially prepared in the initial Bell state, quantum discord can keep longer time and reach larger values in nonMarkovian reservoirs for the first spectral distribution or by reducing the cutoff frequency for the second case. For the initial Bell-like state, the dynamic behaviors of quantum discord and entanglement are compared. The results show that a long time of quantum correlation can be obtained by adjusting some parameters in experiment and further confirm that the discord can capture quantum correlation in addition to entanglement. 展开更多
关键词 Lorentzian and Ohmic spectral densities the time convolution-less projection operator method non-Markovian and Markovian regime quantum discord and entanglement
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Parallel Techniques for Frame Synchronous Scrambler
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作者 Xiaoru, Zh. Lieguang, Z. 《High Technology Letters》 EI CAS 1995年第1期51-54,共4页
In high speed transmission system such as SDH,parallel scrambling technique is re-quired.This paper presents a method of expanding matrix,which makes the traditional ma-trix method capable of realizing parallel scramb... In high speed transmission system such as SDH,parallel scrambling technique is re-quired.This paper presents a method of expanding matrix,which makes the traditional ma-trix method capable of realizing parallel scramblers of any size.A novel method called delayoperator method is also described in this paper.The 8-bit parallel scrambling circuitry ofSDH has been realized with the two methods. 展开更多
关键词 Parallel scramble Matrix method Delay operator method
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Novel Superpotentials for Supersymmetric Quantum Mechanics: A New Mathematical Investigation and Study
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作者 Alireza Heidari Seyedali Vedad Mohammadali Ghorbani 《Journal of Modern Physics》 2012年第4期304-311,共8页
The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari... The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari and Seyedali Vedad. The scientific community takes a very strong view on this matter and we treat all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No.4 304-311, 2012, has been removed from this site. 展开更多
关键词 SUPERPOTENTIALS SUPERSYMMETRIC Quantum Mechanics Schr?dinger Equation operator method Coulomb Superpotential Klein-Gordon Energies
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