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Identifying indigenous tree species for land reforestation,forest restoration, and plantation transformation on Hainan Island, China

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Journal of Mountain Science 2018年第11期15卷 2433-2444页

作者： WANG Jian-jun MENG jing-hui Key Laboratory for Forest Resources and Ecosystem Processes of Belling Belling Forestry University Beijing 100083 China

Selecting suitable species is the most important issue for bare land reforestation, degraded secondary forest restoration, and single-species plantation transformation. However, little information has been documented related to tree species selection for these silvicultural endeavors on tropical Hainan Island of Southern China. The present study employed Baisha County, the ecological core area of Hainan Island, as a case study area. We initially inventoried a slightly disturbed primary forest and attempted to produce diameter distribution curves for each tree species. Second, the tree species were classified into shade intolerant, opportunist, and shade tolerant species based on shape of their diameter distribution curves. Third, market value was determined for each tree species based on published literature and on-site investigations at local wood trading companies. Totally 118 tree species were encountered in the inventoried forest and 13 tree species present were finally identified as potential tree species for our silvicultural endeavor on Hainan Island, of which 3 species are shade intolerant, 5 species are opportunist and 5 species are shade tolerant. Additionally, we also selected 12 tree species that were not in the inventoried forest but were extremely economically valuable and ecologically important. This study should contribute to the formulation of a sustainable forest management strategy on Hainan Island and the methodology might be replicated in other tropical region where suitable species also need to be identified for silvicultural endeavor.

关键词： Diameter distribution curves Primary forest Shade intolerant Opportunist species Shade tolerant Forest management

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A Generalized Vector-valued Variational Principle in Fréchet Spaces

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Acta Mathematica Sinica,English Series 2010年第11期26卷 2145-2156页

作者： jing hui QIU Xin Qing YANG Department of Mathematics Suzhou University Suzhou 215006 P. R. China

In the framework of Frechet spaces, we give a generalized vector-valued Ekeland＇s variational principle, where the perturbation involves the subadditive functions of countable generating semi-norms. By modifying and developing the method of Cammaroto and Chinni, we obtain a density theorem on extremal points of the vector-valued variational principle, which extends and improves the related known results.

关键词： Locally convex space Fr^chet space vector-valued variational principle extremal point density

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Weak-force sensing with squeezed optomechanics

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Science China(Physics,Mechanics & Astronomy) 2020年第2期63卷 71-81页

作者： Wen Zhao Sheng-Dian Zhang Adam Miranowicz hui jing Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China College of Physics and Materials Science Henan Normal UniversityXinxiang 453007China Faculty of Physics Adam Mickiewicz UniversityPozna´n 61-614Poland

We investigate quantum-squeezing-enhanced weak-force sensing via a nonlinear optomechanical resonator containing a movable mechanical mirror and an optical parametric amplifier(OPA). Herein, we determined that tuning the OPA parameters can considerably suppress quantum noise and substantially enhance force sensitivity, enabling the device to extensively surpass the standard quantum limit. This indicates that under realistic experimental conditions, we can achieve ultrahigh-precision quantum force sensing by harnessing nonlinear optomechanical devices.

关键词： weak-force sensing squeezing optomechanics

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Numerical investigation of a muzzle multiphase flow field using two underwater launch methods

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Defence Technology（防务技术） 2022年第8期18卷 1454-1469页

作者： jing-hui Zhang Yong-gang Yu Xin-wei Zhang School of Energy and Power Engineering Nanjing University of Science&TechnologyNanjing210094China

A two-dimensional axisymmetric model, employing a dynamic mesh and user-defined functions, is used to numerically simulate the transient multiphase flow field produced by an underwater gun. Furthermore, a visualized shooting experiment platform with a high-speed camera is built to observe the evolution process of such a multiphase flow field. The simulated phase distribution diagram is agreed well with the shadow photo of the experiment, indicating that the numerical model is reasonable. Further examinations of the multiphase flow fields by using the submerged and sealed launch methods show that use of the sealed launch can significantly improve the interior ballistic performance of an underwater gun. In the cases by using these two types of underwater launch methods, the displacement of the projectile within the range of the muzzle flow field meets the exponential law over time. Moreover, a not fully developed bottle-shaped shock wave is formed when t = 0.4 ms, but this bottle-shaped shock wave expands more rapidly for the sealed launch. In addition, the amplitude of pressure oscillation for the sealed launch is larger than that of the submerged launch, but the pressure oscillation of the sealed launch lasts shorter.

关键词： Underwater launch Multiphase flow Muzzle flow field Numerical simulation Mach disk

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Thermo-field Dynamics of the Casimir Effect and Its Quantum Deformation

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Chinese Physics Letters 2001年第6期18卷 740-742页

作者： jing hui XIE Bing-Hao CHEN jing-Ling Theoretical Physics Division Nankai Institute of MathematicsNankai UniversityTianjin 300071 Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088

The Casimir effect of the deformed cavity field at finite temperature is investigated by generalizing the thermo field dynamics formalism into q-deformed *** has been shown that the impact of q-deformation on the Casimir force only manifests in the finite temperature case and the expression for the ideal pure vacuum remains unchanged,which just coincides with the suggestions of Man’ko et al.[***.A 176(1993)173]about the nature of q-oscillators as the nonlinear vibrations of electromagnetic field.

关键词： field deformed Casimir

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Net Voltage and Phenomenon of Resonance Induced by Chaotic Signal for a Superconducting Junctions Device

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Communications in Theoretical Physics 2006年第4X期46卷 647-650页

作者： LI jing-hui HAN Yin-Xia Department of Physics Ningbo University Ningbo 315211 China

The effects of a quenched chaotic signal on the over-damped motion of the electron pairs of a superconducting junctions device are studied. It is shown that the chaotic signal can induce the net voltage and the phenom... 详细信息

关键词： superconducting junction electron pairs noise

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ENHANCING CHAIN SEGMENTS MOBILITY TO IMPROVE THE FRACTURE TOUGHNESS OF POLYPROPYLENE

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Chinese Journal of Polymer Science 2013年第2期31卷 232-241页

作者： jing-wei Chen Jian Dai jing-hui Yang Nan Zhang Ting Huang 王勇 Key Laboratory of Advanced Technologies of Materials (Ministry of Education) School of Materials Science & Engineering Southwest Jiaotong University

As a part of a serial work about the annealing inducing improvement of fracture toughness of polypropylene （PP） articles, in this work, a highly efficient mobilizer was introduced into PP and the injection-molded samples were annealed at different temperatures. The mobility of chain segments of PP was investigated by measuring the glass transition temperature. Differential scanning calorimetry （DSC） and wide angle X-ray diffraction （WAXD） were used to characterize the variation of crystalline structure of PP during the annealing process. The fracture behaviors including notched Izod impact fracture and universal tensile fracture were investigated to detect the mechanical properties in response to the variations of both chain segments mobility and crystalline structures. It was found that the mobilizer greatly improved the chain segments mobility. Further results showed that the mobilizer also induced apparent changes of the glass transition temperature and the degree of crystallinity of PP during the annealing process. Consequently, the annealed PP samples containing a few amount of mobilizer exhibited largely increased fracture toughness.

关键词： Chain segments mobility Fracture toughness Mobilizer Annealing.

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Transport of Electron Pairs in a Superconducting Junction Device： Underdamped Case

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Communications in Theoretical Physics 2006年第6期45卷 1031-1034页

作者： LI jing-hui HAN Yin-Xia Faculty of Science Ningbo University Ningbo 315211 China

Transport of electron pairs in a superconducting junction device in the underdamped case is investigated. It is shown that the capacitance of the junctions can slow the movement of the electron pairs and reduce the net voltage. It is also shown that, for the underdamped case and the overdamped case, the movement of the electron pairs in this superconducting junctions device has some similar features. By controlling the correlation between the additive and multiplicative noise, the flux can be reversed. In addition, if the additive noise strength （or the temperature T） is large enough, a reversal can also be induced.

关键词： superconducting junction electron pairs noise

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Resonance, Multi-resonance, and Reverse-resonance Induced by Multiplicative Dichotomous Noise

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Communications in Theoretical Physics 2007年第4X期48卷 605-609页

作者： LI jing-hui HAN Yin-Xia Faculty of Science Ningbo University Ningbo 315211 China

A constant-potential system driven by multiplicative dichotomous noise and subject to an input oscillatory signal is investigated. Two phenomena of stochastic resonance are observed. One is the response as a function of the noise＇s parameters; the other is that as a function of the input signal frequency. A phenomenon of multi-resonance （there are three or four peaks） is found for the response as a function of a parameter of the noise. A phenomenon of reverse-resonance is found, for which the response of the system to the signal can be weakened by the presence of the noise （there is an optimal minimum）. These results help in studies of the systems with multiplicative dichotomous noise, such as the semiconductor, the proteins motor, the chemical reaction, and so on.

关键词： stochastic resonance dichotomous noise

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Giant-Resonance for a Four-Dimensionally Coupled System with Dichotomous Noise

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Communications in Theoretical Physics 2007年第4期47卷 672-674页

作者： LI jing-hui HAN Yin-Xia Faculty of Science Ningbo University Ningbo 315211 China

In this paper, we investigate a four-dimensionally coupled system driven by dichotomous noise. A new kind of stochastic resonance is found, for which the response of the system to the input signal can be hugely intens... 详细信息

关键词： super-conducting junction electron pairs spatial-temporal noise

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