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Constructing p, n-forms from p-forms via the Hodge star operator and the exterior derivative

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Communications in Theoretical Physics 2020年第6期72卷 97-105页

作者： jun-jin Peng School of Physics and Electronic Science Guizhou Normal UniversityGuiyangGuizhou 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyangGuizhou 550001China

In this paper,we aim to explore the properties and applications on the operators consisting of the Hodge star operator together with the exterior derivative,whose action on an arbitrary p-form field in n-dimensional spacetimes makes its form degree remain *** operations are able to generate a variety of p-forms with the even-order derivatives of the *** do this,we first investigate the properties of the operators,such as the Laplace–de Rham operator,the codifferential and their combinations,as well as the applications of the operators in the construction of conserved *** the basis of two general p-forms,then we construct a general n-form with higher-order ***,we propose that such an n-form could be applied to define a generalized Lagrangian with respect to a p-form field according to the fact that it includes the ordinary Lagrangians for the p-form and scalar fields as special cases.

关键词： p-form Hodge star Laplace–Beltrami operator Lagrangian for p-form

Hydrocarbon generation from Carboniferous-Permian coaly source rocks in the Huanghua depression under different geological processes

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Petroleum Science 2020年第6期17卷 1540-1555页

作者： jin-jun Xu Qiang jin Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShandongChina Pilot National Laboratory for Marine Science and Technology China University of Petroleum(East China)Aoshanwei Wenhai Road 1Qingdao 266237ShandongChina

Natural gas and condensate derived from Carboniferous-Permian(C-P)coaly source rocks discovered in the Dagang Oilfield in the Bohai Bay Basin(east China)have important implications for the potential exploration of C-P coaly source *** study analyzed the secondary,tertiary,and dynamic characteristics of hydrocarbon generation in order to predict the hydrocarbon potentials of different exploration areas in the Dagang *** results indicated that C-P oil and gas were generated from coaly source rocks by secondary or tertiary hydrocarbon generation and characterized by notably different hydrocarbon products and generation *** hydrocarbon generation was completed when the maturity reached vitrinite reflectance(Ro)of 0.7%-0.9%before uplift prior to the *** hydrocarbon generation from the source rocks was limited in deep buried sags in the Oligocene,where the products consisted of light oil and *** activation energies for secondary and tertiary hydrocarbon generation were 260-280 kJ/mol and 300-330 kJ/mol,respectively,indicating that each instance of hydrocarbon generation required higher temperature or deeper burial than the previous *** with secondary or tertiary hydrocarbon generation from C-P coaly source rocks were interpreted as potential oil and gas exploration regions.

关键词： Hydrocarbon generation Thermal simulation Coaly source rocks Carboniferous-Permian Huanghua depression

RESISTANCE OF FLOW OVER ROUGH BED

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Journal of Hydrodynamics 1991年第4期3卷 49-54页

作者： jin-jun, Wang Beijing Univ of Aeronautics and Astronautics Beijing China

In this paper, the flow resistance in a flume with rough bed was studied, and the criteria of 2-dimensional flow were obtained. The effects of bed roughness on Manning coefficient n and Chezy coefficient C were also discussed, and the experimental results indicate that n and C can be taken as constants for small-scale roughness case.

关键词： Flow of Water Channel Flow Flow of Water Mathematical Models Surfaces Roughness Measurement

Distributed Penalized Modal Regression for Massive Data

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Journal of Systems Science & Complexity 2023年第2期36卷 798-821页

作者： jin jun LIU Shuangzhe MA Tiefeng College of Mathematical Sciences Yangzhou UniversityYangzhou 225002China Faculty of Science and Technology University of CanberraACT 2601Australia School of Statistics Southwestern University of Finance and EconomicsChengdu 661130China

Nowadays,researchers are frequently confronted with challenges from massive data computing by a number of limitations of computer primary *** regression(MR)is a good alternative of the mean regression and likelihood based methods,because of its robustness and high *** this end,the authors extend MR to massive data analysis and propose a computationally and statistically efficient divide and conquer MR method(DC-MR).The major novelty of this method consists of splitting one entire dataset into several blocks,implementing the MR method on data in each block,and deriving final results through combining these regression results via a weighted average,which provides approximate estimates of regression results on the entire *** proposed method significantly reduces the required amount of primary memory,and the resulting estimator is theoretically as efficient as the traditional MR on the entire data *** authors also investigate a multiple hypothesis testing variable selection approach to select significant parametric components and prove the approach possessing the oracle *** addition,the authors propose a practical modified modal expectation-maximization(MEM)algorithm for the proposed *** studies on simulated and real datasets are conducted to assess and showcase the practical and effective performance of our proposed methods.

关键词： Asymptotic distribution divide and conquer massive data modal regression multiple hypothesis testing

Size effects on the mixed modes and defect modes for a nano-scale phononic crystal slab

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Applied Mathematics and Mechanics(English Edition) 2023年第1期44卷 21-34页

作者： jun jin Ningdong HU Hongping HU Department of Mechanics School of Aerospace EngineeringHuazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment Huazhong University of Science and TechnologyWuhan 430074China

The size-dependent band structure of an Si phononic crystal(PnC)slab with an air hole is studied by utilizing the non-classic wave equations of the nonlocal strain gradient theory(NSGT).The three-dimensional(3D)non-classic wave equations for the anisotropic material are derived according to the differential form of the *** on the the general form of partial differential equation modules in COMSOL,a method is proposed to solve the non-classic wave *** bands of the in-plane modes and mixed modes are *** in-plane size effect and thickness effect on the band structure of the PnC slab are *** is found that the thickness effect only acts on the mixed *** relative width of the band gap is widened by the thickness *** effects of the geometric parameters on the thickness effect of the mixed modes are further studied,and a defect is introduced to the PnC supercell to reveal the influence of the size effects with stiffness-softening and stiffness-hardening on the defect *** study paves the way for studying and designing PnC slabs at nano-scale.

关键词： band structure phononic crystal(PnC) nonlocal strain gradient theory(NSGT) size effect

Simulation of dual transponder carrier ranging measurements

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1395-1403页

作者： Xiang-yu ZHA Xiao-jun jin Zhong-he jin Department of lnformation Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

The most dominant error source for microwave ranging is the frequency instability of the oscillator that generates the carrier phase signal. The oscillator noise is very difficult to filter due to its extremely low frequency. A dual transponder carrier ranging method can effectively minimize the oscillator noise by combing the reference phase and the to-and-fro measurement phase from the same single oscillator. This method does not require an accurate time tagging system, since it extracts phases on the same satellite. This paper analyzes the dual transponder carrier ranging system by simulation of the phase measurements with comprehensive error models. Both frequency domain and time domain noise transfer characteristics were simulated to compare them with dual one-way ranging. The simulation results in the two domains conformed to each other and demonstrated that a high level of accuracy can also be achieved by use of the dual transponder carder ranging system, with relatively simple instruments.

关键词： Dual transponder carrier ranging Dual one-way ranging Oscillator noise Transfer characteristic

Third-order elastic, piezoelectric, and dielectric constants

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Applied Mathematics and Mechanics(English Edition) 2019年第12期40卷 1831-1846页

作者： Yanming ZHANG jun jin Hongping HU Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Huazhong University of Science and TechnologyWuhan 430074China

The definitions of the third-order elastic,piezoelectric,and dielectric constants and the properties of the associated tensors are *** on the energy conservation and coordinate transformation,the relations among the third-order constants are ***,the relations among the third-order elastic,piezoelectric,and dielectric constants of the seven crystal systems and isotropic materials are listed in *** third-order constants relations play an important role in solving nonlinear problems of elastic and piezoelectric *** is further found that all third-order piezoelectric constants are 0 for 15 kinds of point groups,while all third-order dielectric constants are 0 for 16 kinds of point groups as well as isotropic *** reason is that some of the point groups are centrally symmetric,and the other point groups are high *** results provide the foundation to measure these constants,to choose material,and to research nonlinear ***,these results are helpful not only for the study of nonlinear elastic and piezoelectric problems,but also for the research on flexoelectric effects and size effects.

关键词： third-order elastic constant third-order piezoelectric constant nonlinear third-order dielectric constant crystal coordinate transformation tensor

Hausdorff dimensions of some irregular sets associated with β-expansions

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Science China Mathematics 2016年第3期59卷 445-458页

作者： LI jin jun LI Bing School of Mathematics and Statistics Minnan Normal University School of Mathematics South China University of Technology

The Hausdorff dimensions of some refined irregular sets associated with β-expansions are determined for any β > 1. More precisely, Hausdorff dimensions of the sets {x ∈ [0, 1) :lim inf(n→∞) S_n(x, β)/n= α_1, lim sup (n→∞) S_n(x, β)/n= α_2}, α_1, α_2≥0 are obtained completely, where S_n(x, β) =sum ε_k(x, β) from k=1 to n denotes the sum of the first n digits of the β-expansion of x. As an application, we present another concise proof of that the set of points x ∈ [0, 1) satisfying lim_(n→∞) S_n(x,β)/n does not exist is of full Hausdorff dimension.

关键词： β-expansion irregular sets Hausdorff dimension

Quantum gravity effects on spectroscopy of Kerr-Newman black hole in gravity's rainbow

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Communications in Theoretical Physics 2022年第2期74卷 90-98页

作者： Cheng-Zhou Liu jin-jun Tao Department of Physics Shaoxing UniversityShaoxing 312000China

The effects of quantum gravity on spectroscopy for the charged rotating gravity’s rainbow are investigated in this *** utilizing an action invariant obtained from particles tunneling through the event horizon,the entropy and area spectrum for the modified Kerr-Newman black hole are *** equally spaced entropy spectrum characteristic of Bekenstein’s original derivation is ***,the entropy spectrum is independent of the energy of the test particles,although the gravity’s rainbow itself is the energy *** that,the quantum gravity effects of gravity’s rainbow has no influence on the entropy *** the other hand,due to the spacetime quantum effects,the obtained area spectrum is different from the original Bekenstein *** is not equidistant and is dependent on the horizon *** that,by analyzing the area spectrum from a specific rainbow function,a minimum area with a Planck scale is derived for the event *** this point,the area quantum is zero and the black hole radiation ***,the black hole remnant for the gravity’s rainbow is obtained from the area *** addition,the entropy for the modified Kerr-Newman black hole is calculated and the quantum correction to the area law is obtained and discussed.

关键词： black hole spectroscopy gravity’s rainbow quantum effects