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Photoproduction of Vector Meson φ off Deuteron in QCD Inspired Model

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Communications in Theoretical Physics 2009年第8期52卷 295-301页

作者： MENG Cheng-Ju pan ji-huan PENG jin-Song MA Wei-Xing YUAN Tong-Quan Department of Physics and Electronic Engineering Hechi College Yizhou 546300 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China

Based on the quark-gluon contents of nucleon and strongly believing that the force mediators,Pomeronand its counterpart in the conventional approach of Regge theory,for high energy diffractive process would be the tensorglueball and Odderon respectively,we discuss photo-production of vector meson φ off the deuteron at energy less than 3GeV in the QCD inspired model in which the quark gluon degrees of freedom and glueball,Odderon exchange are takeninto account.A calculation is performed for γ + D →φ + D,and the theoretical predictions of the differential crosssection dσ^(γD)) /dt,are presented and compared with available experimental *** QCD inspired model reproducesdata quite well in the whole range of the experimental measurements up to |t| ■0.4 *** results can be used toextract γn→φn data,which cannot be measured in experiment.

关键词： photoproduction of vector meson QCD generalized vector meson dominance model QCD

Tensor Susceptibilities of QCD Vacuum and Parameterized Quark Propagator

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Communications in Theoretical Physics 2008年第3期49卷 717-722页

作者： ZHOU Li-Juan MENG Cheng-Ju pan ji-huan LIU Bao-Rong MA Wei-Xing Collaboration Group of Hadron Physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou 545006 China Department of Physics Hechi College Yizhou 546300 China Department of Physics Guangxi University Nanning 530004 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China

Based on the parameterized fully dressed quark propagator proposed by us, the tensor susceptibilities of QCD vacuum and quark vacuum condensates are investigated. Our predicted values of the tensor susceptibilities are in agreement with those predicted by many other theoretical models with QCD feature. The results also show that the tensor susceptibility of QCD vacuum strongly depends on flavor of quark but not sensitive to variation of quark vacuum condensates. However, the quark vacuum condensate is very sensitive to the change of cut-off-parameter μ^2 of the integration, that is, it depends on the separation point of perturbative and non-perturbative QCD region. The successful predictions clearly indicate the extensive validity of our parameterized fully dressed quark propagator used here.

关键词： QCD vacuum tensor susceptibilities quark propagator

A NOTE ON DELTA-PERTURBATION EXpanSION METHOD

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Applied Mathematics and Mechanics(English Edition) 2002年第6期23卷 634-638页

作者： HE ji-huan(何吉欢) Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 P R China

The Delta-perturbation expansion method, a kind of new perturbation technique depending upon an artificial parameter Delta was studied. The study reveals that the method exits some advantages, but also exits some limitations. To overcome the limitations, the so-called linearized perturbation method proposed by HE ji-huan can be powerfully applied.

关键词： perturbation method artificial parameter nonlinear equation homotropy

Uniform and Semi-uniform Convergence for Discontinuous Skew-product Transformation and Observation

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Acta Mathematica Sinica,English Series 2021年第2期37卷 333-344页

作者： Xia pan Zuo huan ZHENG Zhe ZHOU College of Liberal Arts and Sciences National University of Defense TechnologyChangsha 410073P.R.China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190P.R.China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China ollege of Mathematics and Statistics Hainan Normal UniversityHaikou 571158P.R.China

In this paper, for a discontinuous skew-product transformation with the integrable observation function, we obtain uniform ergodic theorem and semi-uniform ergodic theorem. The main assumptions are that discontinuity sets of transformation and observation function are ignorable in some measure-theoretical sense. The theorems extend the classical results which have been established for continuous transformations and continuous observation functions.

关键词： Skew-product transformation uniform ergodicity semi-uniform ergodicity

An Improved Approach for Interaction of Wave with Floating Spheres and Its Applications

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China Ocean Engineering 2023年第1期37卷 115-130页

作者： LIU Can DONG Zhi-yong pan Yun TONG huan-huan YANG li-jing College of Civil Engineering Zhejiang University of TechnologyHangzhou 310023China School of Naval Architecture and Maritime Zhejiang Ocean UniversityZhoushan 316022China School of Marine Engineering Equipments Zhejiang Ocean UniversityZhoushan 316022China

To develop and utilize marine resources in the deep sea, the higher requirements for floating structures, which are operated in marine environment for a long term, have been put forward. Reasonable structure type and accurate force analysis are favorable guarantees to improve the survival performance and working performance of the floating structures. Floating spheres fastened by mooring cable were widely used in floating structures. In this paper, the wave forces of the floating sphere are efficiently and accurately calculated by solving the geometric relationship between the non-submerged floating sphere and wave surface. Combined with the hydrodynamic calculation of mooring cables based on the lumped mass method, the coupled motion model of multi-floating spheres fastened by multi-mooring cable was established under wave action. Furthermore, according to the floating structures fastened by mooring cable in the actual ocean engineering, the topological method of multi-mooring cables fastening the multifloating spheres was expounded from simple to complex. Finally, the modeling method and preliminarily hydrodynamic characteristics of the fastened floating structures, including the mooring system of renewable energy devices, ocean buoy, and coral nursery, were presented and analyzed in detail. The obtained results showed that the method for calculating the wave force on the floating sphere developed in this paper can accurately describe the motion process of the floating mooring sphere and the force on the mooring cable. Also, the topological method of multiple buoys and multiple mooring cables could efficiently establish various numerical hydrodynamic models of fastened buoys in ocean engineering.

关键词： floating sphere mooring cable wave forces hydrodynamic model ocean engineering

A molecular insight into coke formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： ji-Guang Li Xin Guo huan-Di Hou Heavy Oil Processing Department Sinopec Research Institute of Petroleum Processing Co.LtdBeijing100083China

Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the coke formation *** total yields of ideal components including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the conversion ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 *** asphaltene content increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene content occurred at the end of the coking induction *** asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process,and the coke formation pathways were discussed to reveal the coke formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene Coking induction period Sulfur Nitrogen

A method of improving SFDRs of 1-bit signals for a monobit receiver

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Journal of Systems Engineering and Electronics 2022年第2期33卷 330-339页

作者： ji Pengfei SHI Qingzhan LV huan YUAN Naichang School of Electronic Sciences National University of Defense TechnologyChangsha 410073China

This paper proposes a method to improve the spu-rious-free dynamic ranges(SFDRs)of 1-bit sampled signals greatly,which is very beneficial to multi-tone signals ***,the relationship between the fundamental component and the third harmonic component of 1-bit sampled signals is analyzed for determining four contiguous special frequency bands,which do not contain any third harmonics inside and co-ver 77.8%of the whole Nyquist sampling frequency ***,we present a special 4-channel monobit receiver model,where appropriate filter banks are used to obtain four desired pass bands before 1-bit quantization and each channel can sample and process sampled data independently to achieve a good in-stantaneous dynamic range without sacrificing the real-time per-formance or computing *** simulation results show that the proposed method effectively eliminates the effect of the most harmonics on SFDRs and the mean SFDR is increased to to 20 ***,the multi-signals simulation results indicate that the maximum amplitude separation(dynamic range)of two signals in each channel is 12 dB while the proposed monobit re-ceiver can deal with up to eight simultaneous arrival *** general,the designing method proposed in this paper has a po-tential engineering value.

关键词： 1-bit signal monobit third harmonic component spurious-free dynamic range(SFDR)

Leader-following consensus of multi-agent systems with switching topologies and time-delays

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控制理论与应用（英文版） 2013年第2期11卷 306-310页

作者： Ling GUO Xiaohong NIAN huan pan School of Information Science and Engineering Central South University

This paper investigates the leader-following consensus problem of multi-agent systems where the leader is static and the controlling effect of each follower depends on its own state. The control protocols are proposed for two cases： i） for network with switching topologies and undirected information flow; ii） for network with directed information flow and communication time-delays. With the aid of several tools from algebraic graph, matrix theory and stability the- ory, the sufficient conditions guaranteeing leader-following consensus are obtained by constructing appropriate Lyapunov functions. Simulations are presented to demonstrate the effectiveness of our theoretical results.

关键词： Leader-following consensus Multi-agent systems Switching topology Time-delays

Gasser-Leutwyler Coefficients of Chiral Lagrangian for Pseudoscalar Goldstone Bosons

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Communications in Theoretical Physics 2006年第1X期46卷 101-108页

作者： ZHOU Li-Juan WU Qing pan ji-huan MENG Cheng-Ju MA Wei-Xing LI Xi-Guo Collaboration Group of Hadron Physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou 545006 China Department of Physics Qingdao University Qingdao 266071 China Department of Physics Hechi College Yizhou 546300 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000 China

Based on the Dyson-Schwinger equations in raAnbow approximation for quark propagator with an effective gluon propagator, and on the parametrized fully dressed quark propagator proposed by us, the unknown GasserLeutwyler coeiticients of the chiral Lagrangian for pseudoscalar Goldstone bosons, Li, are predicted respectively. The predicted values of Li in the two different ways are not only in reasonable agreement each other but also in agreement with empirical values used widely in literature and the values predicted by many other theoretical models with QCD characteristics. The compatible results of Gasser-Leutwyler coefficients predicted by our parameterized quark propagator, in turn, clearly verify its extensive validity.

关键词： chiral perturbation theory Gasser-Leutwyler coefficient quark propagator Dyson-Schwinger equations