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CONSISTENCY BETWEEN INDEPENDENCE THEOREMS AND GENERALIZED SELF-CONSISTENT METHOD 被引量:1
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作者 杜丹旭 郑泉水 高蕴昕 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1997年第4期355-365,共11页
Recently Zheng & Hwang established a series of independence theorems concerning with planar effective elastic properties. It is manifested that the estimation of the effective elastic properties of microcracked so... Recently Zheng & Hwang established a series of independence theorems concerning with planar effective elastic properties. It is manifested that the estimation of the effective elastic properties of microcracked solids through the generalized self-consistent method (GSCM) contradicts with these independence theorems. In this paper it is shown that such contradiction is actually caused by the approximate algorithm adopted, while the exact solution of GSCM is consistent with these rigorously established independence theorems. Since only an approximate algorithm in GCSM is available in dealing with problems involving non-circular inclusions or holes, an intrinsic GSCM is proposed, which can be performed based on an approximate algorithm and the corresponding estimations are consistent with the independence theorems. 展开更多
关键词 intrinsic Generalised self-consistent method INDEPENDENCE energy equivalence effective properties
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Accelerating Hartree-Fock Self-consistent Field Calculation on C86/DCU Heterogenous Computing Platform
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作者 Ji Qi Huimin Zhang +1 位作者 Dezun Shan Minghui Yang 《Chinese Journal of Chemical Physics》 2025年第1期81-94,I0056,共15页
In this study,we investigate the ef-ficacy of a hybrid parallel algo-rithm aiming at enhancing the speed of evaluation of two-electron repulsion integrals(ERI)and Fock matrix generation on the Hygon C86/DCU(deep compu... In this study,we investigate the ef-ficacy of a hybrid parallel algo-rithm aiming at enhancing the speed of evaluation of two-electron repulsion integrals(ERI)and Fock matrix generation on the Hygon C86/DCU(deep computing unit)heterogeneous computing platform.Multiple hybrid parallel schemes are assessed using a range of model systems,including those with up to 1200 atoms and 10000 basis func-tions.The findings of our research reveal that,during Hartree-Fock(HF)calculations,a single DCU ex-hibits 33.6 speedups over 32 C86 CPU cores.Compared with the efficiency of Wuhan Electronic Structure Package on Intel X86 and NVIDIA A100 computing platform,the Hygon platform exhibits good cost-effective-ness,showing great potential in quantum chemistry calculation and other high-performance scientific computations. 展开更多
关键词 quantum chemistry self-consistent field HARTREE-FOCK Electron repulsion inte-grals Heterogenous parallel computing C86/deep computing unit
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Calculation of Valence Subband Structures for Strained Quantum-Wells by Plane Wave Expansion Method Within 6×6 Luttinger-Kohn Model
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作者 国伟华 黄永箴 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第6期577-581,共5页
The valence subband energies and wave functions of a tensile strained quantum well are calculated by the plane wave expansion method within the 6×6 Luttinger Kohn model.The effect of the number and period of pla... The valence subband energies and wave functions of a tensile strained quantum well are calculated by the plane wave expansion method within the 6×6 Luttinger Kohn model.The effect of the number and period of plane waves used for expansion on the stability of energy eigenvalues is examined.For practical calculation,it should choose the period large sufficiently to ensure the envelope functions vanish at the boundary and the number of plane waves large enough to ensure the energy eigenvalues keep unchanged within a prescribed range. 展开更多
关键词 semiconductor optical amplifier strained quantum well plane wave expansion method POLARIZATION
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Quantum Boltzmann equation solved by Monte Carlo method for nano-scale semiconductor devices simulation 被引量:5
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作者 杜刚 刘晓彦 韩汝琦 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第1期177-181,共5页
A two-dimensional (2D) full band self-consistent ensemble Monte Carlo (MC) method for solving the quantum Boltzmann equation, including collision broadening and quantum potential corrections, is developed to exten... A two-dimensional (2D) full band self-consistent ensemble Monte Carlo (MC) method for solving the quantum Boltzmann equation, including collision broadening and quantum potential corrections, is developed to extend the MC method to the study of nano-scale semiconductor devices with obvious quantum mechanical (QM) effects. The quantum effects both in real space and momentum space in nano-scale semiconductor devices can be simulated. The effective mobility in the inversion layer of n and p channel MOSFET is simulated and compared with experimental data to verify this method. With this method 50nm ultra thin body silicon on insulator MOSFET are simulated. Results indicate that this method can be used to simulate the 2D QM effects in semiconductor devices including tunnelling effect. 展开更多
关键词 quantum mechanical effect Monte Carlo method semiconductor device carrier transport
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Preparation of Hadamard Gate for Open Quantum Systems by the Lyapunov Control Method 被引量:3
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作者 Nourallah Ghaeminezhad Shuang Cong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第3期733-740,共8页
In this paper, the control laws based on the Lyapunov stability theorem are designed for a two-level open quantum system to prepare the Hadamard gate, which is an important basic gate for the quantum computers. First,... In this paper, the control laws based on the Lyapunov stability theorem are designed for a two-level open quantum system to prepare the Hadamard gate, which is an important basic gate for the quantum computers. First, the density matrix interested in quantum system is transferred to vector formation.Then, in order to obtain a controller with higher accuracy and faster convergence rate, a Lyapunov function based on the matrix logarithm function is designed. After that, a procedure for the controller design is derived based on the Lyapunov stability theorem. Finally, the numerical simulation experiments for an amplitude damping Markovian open quantum system are performed to prepare the desired quantum gate. The simulation results show that the preparation of Hadamard gate based on the proposed control laws can achieve the fidelity up to 0.9985 for the different coupling strengths. 展开更多
关键词 Lyapunov control method open quantum system operator preparation quantum Hadamard gate vector space dynamics
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Solving ground eigenvalue and eigenfunction of spheroidal wave equation at low frequency by supersymmetric quantum mechanics method 被引量:2
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作者 唐文林 田贵花 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期121-127,共7页
The spheroidal wave functions are found to have extensive applications in many branches of physics and mathematics. We use the perturbation method in supersymmetric quantum mechanics to obtain the analytic ground eige... The spheroidal wave functions are found to have extensive applications in many branches of physics and mathematics. We use the perturbation method in supersymmetric quantum mechanics to obtain the analytic ground eigenvalue and the ground eigenfunction of the angular spheroidal wave equation at low frequency in a series form. Using this approach, the numerical determinations of the ground eigenvalue and the ground eigenfunction for small complex frequencies are also obtained. 展开更多
关键词 spheroidal wave equation the perturbation method in supersymmetric quantum mechanics super-potential eigenvalue and eigenfunction
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Pseudospin symmetric solutions of the Dirac equation with the modified Rosen-Morse potential using Nikiforov-Uvarov method and supersymmetric quantum mechanics approach 被引量:3
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作者 Wen-Li Chen I B Okon 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期107-112,共6页
Employing the Pekeris-type approximation to deal with the pseudo-centrifugal term,we analytically study the pseudospin symmetry of a Dirac nucleon subjected to equal scalar and vector modified Rosen-Morse potential in... Employing the Pekeris-type approximation to deal with the pseudo-centrifugal term,we analytically study the pseudospin symmetry of a Dirac nucleon subjected to equal scalar and vector modified Rosen-Morse potential including the spin-orbit coupling term by using the Nikiforov-Uvarov method and supersymmetric quantum mechanics approach.The complex eigenvalue equation and the total normalized wave functions expressed in terms of Jacobi polynomial with arbitrary spin-orbit coupling quantum number k are presented under the condition of pseudospin symmetry.The eigenvalue equations for both methods reproduce the same result to affirm the mathematical accuracy of analytical calculations.The numerical solutions obtained for different adjustable parameters produce degeneracies for some quantum number. 展开更多
关键词 Dirac equation modified Rosen-Morse potential Nikiforov-Uvarov method supersymmetric quantum mechanics approach
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Security Simulation of Continuous-Variable Quantum Key Distribution over Air-to-Water Channel Using Monte Carlo Method 被引量:1
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作者 Cai-Lang Xie Ying Guo +2 位作者 Yi-Jun Wang Duan Huang Ling Zhang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第9期10-13,共4页
Considering the ocean water's optical attenuation and the roughness of the sea surface, we analyze the security of continuous-variable (CV) quantum key distribution (QKD) based Mr-to-water channel. The effects of... Considering the ocean water's optical attenuation and the roughness of the sea surface, we analyze the security of continuous-variable (CV) quantum key distribution (QKD) based Mr-to-water channel. The effects of the absorp- tion and scattering on the transmittance of underwater quantum channel and the maximum secure transmission distance are studied. Considering the roughness of the sea surface, we simulate the performance bounds of CV QKD with different wind speeds using the Monte Carlo method. The results show that even if the secret key rate gradually reduces as the wind speed increases, the maximum transmission distance will not be affected obviously. Compared to the works regarding short-distance underwater optical communication, our research represents a significant step towards establishing secure communication between air platform and submarine vehicle. 展开更多
关键词 QKD Security Simulation of Continuous-Variable quantum Key Distribution over Air-to-Water Channel Using Monte Carlo method CV
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The Quantum Scattering Study for Ion-pair Formation Reaction Na+I_2→Na^+I_2^- with the LCAC-SW method
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作者 Wan Yong MA Da Cheng FENG +1 位作者 Zheng Ting CAI Cong Hao DENG(Institute of Theoretical Chemistry, Shandong University, Jinan 250100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第4期325-326,共2页
The selected-state probabilities of collinear ion-pair formation process Na+I2→Na++I2-on Aten-Laming-Los two-State potential energy surface have been calculated by using LCAC-SW method. The results show that reaction... The selected-state probabilities of collinear ion-pair formation process Na+I2→Na++I2-on Aten-Laming-Los two-State potential energy surface have been calculated by using LCAC-SW method. The results show that reaction probabilities are oscillatory with collision energy; the threshold energy of this ioniZation reaction is 2.8 ev, which is in modest agreement with experimental result. 展开更多
关键词 Ion-pair formation reaction probability quantum scattering LCAC-SW method
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The Study of Alcoholysis of 1,2-Thiazetidine-l,l-dioxide with Quantum Chemical Method
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作者 MaoXiaHE FengZHU DaChengFENG ZhengTingCAI 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第6期745-748,共4页
The alcoholysis mechanism of 1,2-thiazetidine-1,1-dioxide with methanol, in which the relatively stable product is sulfonate ester, has been investigated by quantum chemical method. Our calculations indicate the react... The alcoholysis mechanism of 1,2-thiazetidine-1,1-dioxide with methanol, in which the relatively stable product is sulfonate ester, has been investigated by quantum chemical method. Our calculations indicate the reaction for alcoholysis of 1,2-thiazetidine-1,1-dioxide proceeds via two possible mechanisms: concerted and stepwise. In the stepwise mechanism, two possible reaction pathways can be followed while only one possible reaction pathway can be followed in the concerted mechanism. 展开更多
关键词 1 2-Thiazetidine-1 1-dioxide ALCOHOLYSIS quantum chemical method.
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The analytical transfer matrix method for quantum reflection
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作者 许田 曹庄琪 方靖淮 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期56-61,共6页
In this paper, the analytical transfer matrix method (ATMM) is applied to study the properties of quantum reflection in three systems: a sech2 barrier, a ramp potential and an inverse harmonic oscillator. Our resul... In this paper, the analytical transfer matrix method (ATMM) is applied to study the properties of quantum reflection in three systems: a sech2 barrier, a ramp potential and an inverse harmonic oscillator. Our results agree with those obtained by Landau and Lifshitz [Landau L D and Lifshitz E M 1977 Quantum Mechanics (Non-relativistic Theory) (New York: Pergamon)], which proves that ATMM is a simple and effective method for quantum reflection. 展开更多
关键词 analytical transfer matrix method quantum reflection reflection coemcient transmission coefficient reflection time
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An optimized encoding method for secure key distribution by swapping quantum entanglement and its extension
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作者 高干 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期183-188,共6页
Song [Song D 2004 Phys. Rev. A69034301] first proposed two key distribution schemes with the symmetry feature.We find that, in the schemes, the private channels which Alice and Bob publicly announce the initial Bell s... Song [Song D 2004 Phys. Rev. A69034301] first proposed two key distribution schemes with the symmetry feature.We find that, in the schemes, the private channels which Alice and Bob publicly announce the initial Bell state or the measurement result through are not needed in discovering keys, and Song’s encoding methods do not arrive at the optimization.Here, an optimized encoding method is given so that the efficiencies of Song’s schemes are improved by 7/3 times. Interestingly, this optimized encoding method can be extended to the key distribution scheme composed of generalized Bell states. 展开更多
关键词 quantum key distribution optimized encoding method entanglement swapping generalized Bell states
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A numerical Hartree self-consistent field calculation of an autoionization resonance parameters for a doubly excited 2s^2, 3s^2, and 4s^2 states of He atom with a complex absorbing potential
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作者 Tsogbayar Tsednee Danny L Yeager 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第8期114-122,共9页
The self-consistent Hartree-Fock equation for the He atom is solved using the pseudospectral method. The Feshbach- type autoionization resonance parameters for doubly excited 2s2, 3s2, and 4s2 IS states of He have bee... The self-consistent Hartree-Fock equation for the He atom is solved using the pseudospectral method. The Feshbach- type autoionization resonance parameters for doubly excited 2s2, 3s2, and 4s2 IS states of He have been determined by adding a complex absorbing potential to the Hamiltonian. The Riss-Meyer iterative and Pad6 extrapolation methods are applied to obtain reliable values for the autoionization resonance parameters, which are compared to previous results in the literature. 展开更多
关键词 self-consistent field Hartree-Fock equation helium autoionization pseudospectral method
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Self-consistent tomography of temporally correlated errors
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作者 Mingxia Huo Ying Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第7期59-74,共16页
The error model of a quantum computer is essential for optimizing quantum algorithms to minimize the impact of errors using quantum error correction or error mitigation.Noise with temporal correlations,e.g.low-frequen... The error model of a quantum computer is essential for optimizing quantum algorithms to minimize the impact of errors using quantum error correction or error mitigation.Noise with temporal correlations,e.g.low-frequency noise and context-dependent noise,is common in quantum computation devices and sometimes even significant.However,conventional tomography methods have not been developed for obtaining an error model describing temporal correlations.In this paper,we propose self-consistent tomography protocols to obtain a model of temporally correlated errors,and we demonstrate that our protocols are efficient for low-frequency noise and context-dependent noise. 展开更多
关键词 self-consistent tomography temporally correlated errors quantum computer
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Energy level of an electron in a saddle-potential quantum dot under a uniform magnetic field obtained by the invariant eigenoperator method
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作者 谢传梅 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期47-51,共5页
We show that the recently proposed invariant eigenoperator method can be successfully applied to solving the energy levels of an electron in a saddle-potential quantum dot under a uniform magnetic field. The Landau di... We show that the recently proposed invariant eigenoperator method can be successfully applied to solving the energy levels of an electron in a saddle-potential quantum dot under a uniform magnetic field. The Landau diamagnetism decreases with the value wy2 - wx2 due to the existence of the saddle potential. 展开更多
关键词 saddle-potential quantum dot energy level of electron invariant eigenoperator method
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An analytical variational method for the biased quantum Rabi model in the ultra-strong coupling regime
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作者 Bin-Bin Mao Maoxin Liu +3 位作者 Wei WU Liangsheng Li Zu-Jian Ying Hong-Gang Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期322-327,共6页
An analytical variational method for the ground state of the biased quantum Rabi model in the ultra-strong coupling regime is presented. This analytical variational method can be obtained by a unitary transformation o... An analytical variational method for the ground state of the biased quantum Rabi model in the ultra-strong coupling regime is presented. This analytical variational method can be obtained by a unitary transformation or alternatively by assuming the form of the ground state wave function. The key of the method is to introduce a variational parameter λ,which can be determined by minimizing the energy functional. Using this method, we calculate the physical observables with high accuracy in comparison with the numerical exact ones. Our method evidently improves over the widely used general rotating-wave approximation(GRWA) in both qualitative and quantitative aspects. 展开更多
关键词 ultra-strong coupling biased quantum Rabi model analytical variational method
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An Entropy Measurement Method of Quantum Information System under Uncertain Environment
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作者 Zijing Li Jiangnan Deng +2 位作者 Bing Zhou Ying Liu Zhengying Cai 《International Journal of Intelligence Science》 2018年第2期29-41,共13页
Under uncertain environment, it is very difficult to measure the entropy of quantum information system, because there is no effective method to model the randomness. First, different from the traditional classic uncer... Under uncertain environment, it is very difficult to measure the entropy of quantum information system, because there is no effective method to model the randomness. First, different from the traditional classic uncertainty, a quantum uncertain model is proposed to simulate a quantum information system under uncertain environment, and to simplify the entropy measurement of quantum information system. Second, different from the classic random seed under uncertain environment which is often called as pseudo-random number, here the quantum random is employed to provide us a true random model for the entropy of quantum information system. Third, the complex interaction and entangling activity of uncertain factors of quantum information is modeled as quantum binary instead of classic binary, which can help us to evaluate the entropy of uncertain environment, to analyze the entropy divergence in quantum information system. This work presents a non-classic risk factor measurement for quantum information system and a helpful entropy measurement. 展开更多
关键词 ENTROPY Measurement method quantum Information System UNCERTAIN ENVIRONMENT quantum ENCRYPTION
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Exact Solutions of Non-isospectral sine-Gordon Equation with Self-consistent Sources
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作者 BI Jin-Bo ZHANG Da-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第12期971-978,共8页
The non-isospectral sine-Gordon equation with self-consistent sources is derived.Its solutions are obtainedby means of Hirota method and Wronskian technique,respectively.Non-isospectral dynamics including one-solitonc... The non-isospectral sine-Gordon equation with self-consistent sources is derived.Its solutions are obtainedby means of Hirota method and Wronskian technique,respectively.Non-isospectral dynamics including one-solitoncharacteristics,two-soliton scattering,and ghost solitons,are investigated. 展开更多
关键词 soliton equations with self-consistent sources bilinear method exact solutions
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KdV Equation with Self-consistent Sources in Non-uniform Media
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作者 HAO Hong-Hai WANG Guang-Sheng ZHANG Da-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第6期989-999,共11页
Two non-isospectral KdV equations with self-consistent sources are derived. Gauge transformation between the first non-isospectral KdV equation with self-consistent sources (corresponding to λt = -2aA) and its isos... Two non-isospectral KdV equations with self-consistent sources are derived. Gauge transformation between the first non-isospectral KdV equation with self-consistent sources (corresponding to λt = -2aA) and its isospectral counterpart is given, from which exact solutions for the first non-isospectral KdV equation with self-consistent sources is easily listed. Besides, the soliton solutions for the two equations are obtained by means of Hirota's method and Wronskian technique, respectively. Meanwhile, the dynamical properties for these solutions are investigated. 展开更多
关键词 non-isospectral KdV equation with self-consistent sources gauge transformation Hirota's method Wronskian technique dynamics
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A method to calculate effective Hamiltonians in quantum information
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作者 Jun-Hang Ren Ming-Yong Ye Xiu-Min Lin 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第11期114-119,共6页
Effective Hamiltonian method is widely used in quantum information.We introduce a method to calculate effective Hamiltonians and give two examples in quantum information to demonstrate the method.We also give a relati... Effective Hamiltonian method is widely used in quantum information.We introduce a method to calculate effective Hamiltonians and give two examples in quantum information to demonstrate the method.We also give a relation between the effective Hamiltonian in the Shr?dinger picture and the corresponding effective Hamiltonian in the interaction picture.Finally,we present a relation between our effective Hamiltonian method and the James–Jerke method which is currently used by many authors to calculate effective Hamiltonians in quantum information science. 展开更多
关键词 effective Hamiltonian method quantum information
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