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Computing Ground State Solution of Bose-Einstein Condensates Trapped in One-Dimensional Harmonic Potential

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Communications in Theoretical Physics 2006年第5X期46卷 873-878页

作者： YUAN Qing-Xin ding guo-hui Department of Mathematics and Physics Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

For Bose-Einstein condensates trapped in a harmonic potential well, we present numerical results from solving the tlme-dependent nonlinear Schrolinger equation based on the Crank-Nicolson method. With this method we are able to find the ground state wave function and energy by evolving the trial initial wave function in real and imaginary time spaces, respectively. In real time space, the results are in agreement with [Phys. Rev. A 51 （1995） 4704], but the trial wave function is restricted in a very small range. On the contrary, in imaginary time space, the trial wave function can be chosen widely, moreover, the results are stable.

关键词： Bose-Einstein condensates nonlinear Schrodinger equation Crank-Nicolson method

Numerical Study of φ^4 Model by Potential Importance Sampling Method

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Communications in Theoretical Physics 2006年第5期45卷 873-876页

We investigate the phenomena of spontaneous symmetry breaking for φ^4 model on a square lattice in the parameter space by using the potential importance samplingmethod, which was proposed by Milchev, Heermann, and Binder [J. Star. Phys. 44 （1986） 749]. The critical values of the parameters allow us to determine the phase diagram of the model. At the same time, some relevant quantifies such as susceptibility and specific heat are also obtained.

关键词： symmetry breaking potential importance sampling method φ4 model

The Edge Magnetization and Strip Phase of Graphene Quantum Dots with Long-Range Coulomb Interaction

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Chinese Physics Letters 2014年第4期31卷 150-154页

作者： LINing ZHU Wen-Huan LIANG Qi ding guo-hui Instrumental Analysis Center Shanghai Jiao Tong University Shanghai 200240 Key Laboratory of Artificial Structures and Quantum Control (Ministry of Bducation) Department of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240

We investigate the magnetism and optical absorption properties of charge neutral hexagonal graphene quantum dots （GODs） terminated with zigzag edges by using a tight-binding Hubbard type model for the 7r electrons. Within the Hartree Fock approximation and taking into account the long-range Coulomb interaction, our cal- culation yields a ferromagnetic ground state with magnetic moments localized on the edges for GODs, and also gives an antiferromagnetism state with the energy very c/ose to the ferromagnetism ground state. We find that both the ferromagnetic and the antiferrornagnetic states have stripe patterned charge density distributions as a result of the long-range Coulomb interaction. The optical conductivity for GQDs has an energy gap in the low frequency regime in contrast to the bulk neutral graphene sheet where a universal constant is approached.

关键词： Interaction The Edge Magnetization magnetism

The Numerical Study of the S = 1/2 XXZ Chain

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Communications in Theoretical Physics 2001年第10期36卷 483-486页

作者： YE Fei ding guo-hui XU Bo-Wei Department of Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

We adopt the Lanczos method combined with the quantum conformal field theory to investigate the S = 1/2XXZ chain in detail. The bulk-limit ground state energy, the anomalous scaling dimension of the spin operators, theFermi velocity and the zero-temperature susceptibility are numerically calculated. The results agree to the exact solution well.

关键词： quantized spin models, strongly correlated electron systems, Lanczos method

Phase Transition of Spin-Peierls Systems with Impurities

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Chinese Physics Letters 2000年第8期17卷 552-554页

作者： XU Bo-Wei ding guo-hui YE Fei Department of Physics Shanghai Jiao Tong UniversityShanghai 200030

The quasi-one-dimensional spin-Peierls(SP)systems with impurities are studied in their bosonized *** spins of the dimerized state are bounded into singlets with an SP gap,while the impurities of doped systems will induce fluctuations of the coupling strength between the spins at different sites and break some pairs of spin *** doping suppresses the dimerized SP state and induces a Kosterlitz-Thouless phase transition from the dimerized state into the undimerized one.

关键词： form. singlet dimer

Study on the off situ reconstruction of the core neutron field based on dual-task hybrid network architecture

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Nuclear Science and Techniques 2025年第1期36卷 175-191页

作者： Pei Cao hui ding Cheng-Long Cao Zi-hui Yang guo-Min Sun School of Artificial Intelligence and Big Data Hefei UniversityHefei 230001China College of Electronic Engineering National University of Defense TechnologyHefei 230001China Institute of Nuclear Energy Safety Technology HFIPSChinese Academy of SciencesHefei 230027China

The off situ accurate reconstruction of the core neutron field is an important step in realizing real-time reactor *** existing off situ reconstruction method of the neutron field is only applicable to cases wherein a single region changes at a specified location of the ***,when the neutron field changes are complex,the accurate identification of the individual changed regions becomes challenging,which seriously affects the accuracy and stability of the neutron field ***,this study proposed a dual-task hybrid network architecture(DTHNet)for off situ reconstruction of the core neutron field,which trained the outermost assembly reconstruction task and the core reconstruction task jointly such that the former could assist the latter in the reconstruction of the core neutron field under core complex ***,to exploit the characteristics of the ex-core detection signals,this study designed a global-local feature upsampling module that efficiently distributed the ex-core detection signals to each reconstruction unit to improve the accuracy and stability of *** experiments were performed on the simulation datasets of the CLEAR-I reactor to verify the accuracy and stability of the proposed *** results showed that when the location uncertainty of a single region did not exceed nine and the number of multiple changed regions did not exceed ***,the reconstructed ARD was within 2%,RD_(max)was maintained within 17.5%,and the number of RD≥10%was maintained within ***,when the noise interference of the ex-core detection signals was within±2%,although the average number of RD≥10%increased to 16,the average ARD was still within in 2%,and the average RD_(max)was within 22%.Collectively,these results show that,theoretically,the DTHNet can accurately and stably reconstruct most of the neutron field under certain complex core changes.

关键词： Real-time reactor monitoring Core neutron field reconstruction Dual-task hybrid network architecture Global-local feature upsampling module

Pharmacological management of portal hypertension:current status and future

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Chinese Medical Journal 2020年第19期133卷 2362-2364页

作者： Zhu-Qing Gao Ying Han Lei Li hui-guo ding Department of Gastroenterology and Hepatology Beijing You'an Hospital Affiliated to Capital Medical UniversityBeijing 100069China.

Portal hypertension(PHT)is the trigger of the severe complications of cirrhosis,in eluding esophagogastric variceal bleeding(EVB),ascites,hepatic encephalopathy,cirrhotic cardiomyopathy,acute kidney injury and hepatorenal syndrome(AKI-HRS),which may cause death or increase the need for liver transplantation.11Of these,EVB remains one of the deadliest complications of *** of now,the most widely accepted measure to assess portal pressure(PP)and PHT is the hepatic venous pressure gradient(HVPG)via transjugular-hepatic vein balloon catheterization?

关键词： hypertension balloon hepatic

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基于直方图互确认的图像阈值化分割

红外与毫米波学报 2011年第1期30卷 80-84页

作者：陈亮丁国辉郭雷西北工业大学自动化学院陕西西安710072 天津津航计算技术研究所天津300141

目前图像阈值化中存在的主要问题是分割结果的有效性以及分割数目的确定,本文提出一种新颖并且原理简单的图像阈值化算法.根据图像在直方图上的直观分布,提出一种新的阈值判断机制,该机制基于峰谷对阈值的影响,累积所有直方图对阈值的... 详细信息

目前图像阈值化中存在的主要问题是分割结果的有效性以及分割数目的确定,本文提出一种新颖并且原理简单的图像阈值化算法.根据图像在直方图上的直观分布,提出一种新的阈值判断机制,该机制基于峰谷对阈值的影响,累积所有直方图对阈值的认可程度,并结合一些加速策略,使得算法具有很强的实用性和适用性.算法结合最终的认可程度的百分比确定取值数目,进而确定分割数目.在实验中,引入两种较新的阈值化方法,本文算法的分割效果在实验比较中表现良好,也很稳定.该方法在红外图像处理中也得到较为显著的分割效果.

关键词：图像处理阈值化直方图互确认

Cylindrical Helix Spline Approximation of Spatial Curves

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International Journal of Plant Engineering and Management 2007年第2期12卷 69-78页

作者： ding guo-long ZHOU hui-cheng CHEN Ji-hong National NC System Engineering Research Center Huazhong University of Science and Technology Wuhan 430074 P. R. China

In this paper, we present a new method for approximating spatial curves with a G^1 cylindrical helix spline within a prescribed tolerance. We deduce the general formulation of a cylindrical helix, which has 11 freedoms. This means that it needs 11 restrictions to determine a cylindrical helix. Given a spatial parametric curve segment, including the start point and the end point of this segment, the tangent and the principal normal of the start point, we can always find a cylindrical segment to interpolate the given direction and position vectors. In order to approximate the known parametric curve within the prescribed tolerance, we adopt the trial method step by step. First, we must ensure the helix segment to interpolate the given two end points and match the principal normal and tangent of the start point, and then, we can keep the deviation between the cylindrical helix segment and the known curve segment within the prescribed tolerance everywhere. After the first segment had been formed, we can construct the next segment. Circularly, we can construct the G^1 cylindrical helix spline to approximate the whole spatial parametric curve within the prescribed tolerance. Several examples are also given to show the efficiency of this method.

关键词： cylindrical helix spline approximation spatial curves method