期刊文献+
共找到4,189篇文章
< 1 2 210 >
每页显示 20 50 100
On the Weyl’s Lemma for Triharmonic Functions
1
作者 ZHENG Run-jie ZENG Jia-min FANG Yi 《Chinese Quarterly Journal of Mathematics》 2024年第3期288-294,共7页
In this paper,by choosing some appropriate test functions,we prove the Weyl’s lemma for triharmonic functions based on the new type of mean value formulas.
关键词 Weyl’s lemma Harmonic functions Triharmonic functions Test functions Mean value formulas
下载PDF
A Set of Almost Automorphic Functions and Applications
2
作者 William Dimbour Vincent Valmorin 《Applied Mathematics》 2024年第1期9-21,共13页
For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-al... For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem. 展开更多
关键词 Almost Automorphic functions s-Almost Automorphic functions Differential Equation with Piecewise Constant Argument of Generalized Type
下载PDF
Deep brain implantable microelectrode arrays for detection and functional localization of the subthalamic nucleus in rats with Parkinson’s disease 被引量:1
3
作者 Luyi Jing Zhaojie Xu +11 位作者 Penghui Fan Botao Lu Fan Mo Ruilin Hu Wei Xu Jin Shan Qianli Jia Yuxin Zhu Yiming Duan Mixia Wang Yirong Wu Xinxia Cai 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期439-452,共14页
The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep location.Multichannel micr... The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep location.Multichannel microelectrode arrays(MEAs)can rapidly and precisely locate the STN,which is important for precise stimulation.In this paper,16-channel MEAs modified with multiwalled carbon nanotube/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(MWCNT/PEDOT:PSS)nanocomposites were designed and fabricated,and the accurate and rapid identification of the STN in PD rats was performed using detection sites distributed at different brain depths.These results showed that nuclei in 6-hydroxydopamine hydrobromide(6-OHDA)-lesioned brains discharged more intensely than those in unlesioned brains.In addition,the MEA simultaneously acquired neural signals from both the STN and the upper or lower boundary nuclei of the STN.Moreover,higher values of spike firing rate,spike amplitude,local field potential(LFP)power,and beta oscillations were detected in the STN of the 6-OHDA-lesioned brain,and may therefore be biomarkers of STN localization.Compared with the STNs of unlesioned brains,the power spectral density of spikes and LFPs synchronously decreased in the delta band and increased in the beta band of 6-OHDA-lesioned brains.This may be a cause of sleep and motor disorders associated with PD.Overall,this work describes a new cellular-level localization and detection method and provides a tool for future studies of deep brain nuclei. 展开更多
关键词 functional localization Implantable microelectrode arrays Parkinson’s disease subthalamic nucleus
下载PDF
Functions of Allusions from Leppihalme’s model
4
作者 倪志莉 《魅力中国》 2009年第15期188-189,共2页
The general function of allusions is often thought to add clarity and significance to ideas and descriptions.However,it would be difficult to establish an exhaustive list of mutually exclusive category
关键词 functions of Allusions from Leppihalme’s model
下载PDF
SOME INEQUALITIES OF HERMITE-HADAMARD TYPE FOR s-CONVEX FUNCTIONS 被引量:9
5
作者 Mohammad W. Alomari Maslina Darus Ugur S. Kirmaci 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1643-1652,共10页
In this paper several inequalities of the left-hand side of Hermite-Hadamard’s inequality are obtained for s-convex functions.
关键词 convex function s-convex function Hadamard’s inequality
下载PDF
Green's functions for uniformly distributed loads acting on an inclined line in a poroelastic layered site 被引量:15
6
作者 梁建文 尤红兵 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第2期233-241,共9页
Based on one type of practical Biot's equation and the dynamic-stiffness matrices ofa poroelastic soil layer and half-space, Green's functions were derived for unitformly distributed loads acting on an inclined line... Based on one type of practical Biot's equation and the dynamic-stiffness matrices ofa poroelastic soil layer and half-space, Green's functions were derived for unitformly distributed loads acting on an inclined line in a poroelastie layered site. This analysis overcomes significant problems in wave scattering due to local soil conditions and dynamic soil-structure interaction. The Green's functions can be reduced to the case of an elastic layered site developed by Wolf in 1985. Parametric studies are then carried out through two example problems. 展开更多
关键词 Green's function poroelastic layered site Biot's equation uniformly distributed load wave scattering
下载PDF
Integral Inequalities of Hermite-Hadamard Type for Functions Whose 3rd Derivatives Are <i>s</i>-Convex 被引量:4
7
作者 Ling Chun Feng Qi 《Applied Mathematics》 2012年第11期1680-1685,共6页
In the paper, the authors find some new inequalities of Hermite-Hadamard type for functions whose third derivatives are s-convex and apply these inequalities to discover inequalities for special means.
关键词 INTEGRAL INEQUALITY Hermite-Hadamard’s INTEGRAL INEQUALITY s-Convex function Derivative Mean
下载PDF
ON THE LOWER BOUND FOR A CLASS OF HARMONIC FUNCTIONS IN THE HALF SPACE 被引量:4
8
作者 张艳慧 邓冠铁 高洁欣 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1487-1494,共8页
The main objective is to derive a lower bound from an upper one for harmonic functions in the half space, which extends a result of B. Y. Levin from dimension 2 to dimension n 〉 2. To this end, we first generalize th... The main objective is to derive a lower bound from an upper one for harmonic functions in the half space, which extends a result of B. Y. Levin from dimension 2 to dimension n 〉 2. To this end, we first generalize the Carleman's formula for harmonic functions in the half plane to higher dimensional half space, and then establish a Nevanlinna's representation for harmonic functions in the half sphere by using HSrmander's theorem. 展开更多
关键词 harmonic function Carleman's formula Nevanlinna's representation for halfsphere lower bound
下载PDF
Decoupling coefficients of dilatational wave for Biot's dynamic equation and its Green's functions in frequency domain 被引量:2
9
作者 Boyang DING A.H.D.CHENG Zhanglong CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第1期121-136,共16页
Green's functions for Blot's dynamic equation in the frequency domain can be a highly useful tool for the investigation of dynamic responses of a saturated porous medium. Its applications are found in soil dynamics,... Green's functions for Blot's dynamic equation in the frequency domain can be a highly useful tool for the investigation of dynamic responses of a saturated porous medium. Its applications are found in soil dynamics, seismology, earthquake engineering, rock mechanics, geophysics, and acoustics. However, the mathematical work for deriving it can be daunting. Green's functions have been presented utilizing an analogy between the dynamic thermoelasticity and the dynamic poroelasticity in the frequency domain using the u-p formulation. In this work, a special term "decoupling coefficient" for the decomposition of the fast and slow dilatational waves is proposed and expressed to present a new methodology for deriving the poroelastodynamic Green's functions. The correct- ness of the solution is demonstrated by numerically comparing the current solution with Cheng's previous solution. The separation of the two waves in the present methodology allows the more accurate evaluation of Green's functions, particularly the solution of the slow dilatational wave. This can be advantageous for the numerical implementation of the boundary element method (BEM) and other applications. 展开更多
关键词 decoupling coefficient dilatational wave Biot's equation poroelastodynamic Green's function frequency domain
下载PDF
TIME-HARMONIC DYNAMIC GREEN'S FUNCTIONS FOR ONE-DIMENSIONAL HEXAGONAL QUASICRYSTALS 被引量:3
10
作者 Wang Xu 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第4期302-306,共5页
Quasicrystals have additional phason degrees of freedom not found in conventional crystals. In this paper, we present an exact solution for time-harmonic dynamic Green's function of one-dimensional hexagonal quasicry... Quasicrystals have additional phason degrees of freedom not found in conventional crystals. In this paper, we present an exact solution for time-harmonic dynamic Green's function of one-dimensional hexagonal quasicrystals with the Laue classes 6/mh and 6/mhmm. Through the introduction of two new functions φ and ψ, the original problem is reduced to the determination of Green's functions for two independent Helmholtz equations. The explicit expressions of displacement and stress fields are presented and their asymptotic behaviors are discussed. The static Green's function can be obtained by letting the circular frequency approach zero. 展开更多
关键词 dynamic Green's function one-dimensional hexagonal quasicrystal Helmholtz equation
下载PDF
In-plane dynamic Green's functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic half-space 被引量:3
11
作者 Ba Zhenning Kang Zeqing Liang Jianwen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第2期293-309,共17页
The dynamic stiffness method combined with the Fourier transform is utilized to derive the in-plane Green’s functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic(TI)half-s... The dynamic stiffness method combined with the Fourier transform is utilized to derive the in-plane Green’s functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic(TI)half-space.The loaded layer is fixed to obtain solutions restricted in it and the corresponding reactions forces,which are then applied to the total system with the opposite sign.By adding solutions restricted in the loaded layer to solutions from the reaction forces,the global solutions in the wavenumber domain are obtained,and the dynamic Green’s functions in the space domain are recovered by the inverse Fourier transform.The presented formulations can be reduced to the isotropic case developed by Wolf(1985),and are further verified by comparisons with existing solutions in a uniform isotropic as well as a layered TI halfspace subjected to horizontally distributed loads which are special cases of the more general problem addressed.The deduced Green’s functions,in conjunction with boundary element methods,will lead to significant advances in the investigation of a variety of wave scattering,wave radiation and soil-structure interaction problems in a layered TI site.Selected numerical results are given to investigate the influence of material anisotropy,frequency of excitation,inclination angle and layered on the responses of displacement and stress,and some conclusions are drawn. 展开更多
关键词 Green's functions transversely isotropic medium multi-layered half-space stiffness method dynamic response
下载PDF
Effect of vegetation on soil bacteria and their potential functions for ecological restoration in the Hulun Buir Sandy Land,China 被引量:3
12
作者 YAN Ru FENG Wei 《Journal of Arid Land》 SCIE CSCD 2020年第3期473-494,共22页
To date,much of research on revegetation has focused on soil microorganisms due to their contributions in the formation of soil and soil remediation process.However,little is known about the soil bacteria and their fu... To date,much of research on revegetation has focused on soil microorganisms due to their contributions in the formation of soil and soil remediation process.However,little is known about the soil bacteria and their functions respond to the diverse vegetational types in the process of vegetation restoration.Effects of dominated vegetation,i.e.,Artemisia halodendron Turcz Ex Bess,Caragana microphylla Lam.,Hedysarum fruticosum Pall.and Pinus sylvestris L.on bacterial community structures and their potential functions in the Hulun Buir Sandy Land,China were determined using high-throughput 16S rRNA gene sequencing and phylogenetic investigation of communities by reconstruction of unobserved states(PICRUSt)in 2015.Although the dominant phyla of soil bacterial community among different types of vegetation,including Proteobacteria,Actinobacteria,Acidobacteria,Bacteroidetes and Firmicutes,were similar,the relative abundance of these dominant groups significantly differed,indicating that different types of vegetation might result in variations in the composition of soil bacterial community.In addition,functional genes of bacterial populations were similar among different types of vegetation,whereas its relative abundance was significantly differed.Most carbon fixation genes showed a high relative abundance in P.sylvestris,vs.recalcitrant carbon decomposition genes in A.halodendron,suggesting the variations in carbon cycling potential of different types of vegetation.Abundance of assimilatory nitrate reduction genes was the highest in P.sylvestris,vs.dissimilatory nitrate reduction and nitrate reductase genes in A.halodendron,indicating higher nitrogen gasification loss and lower nitrogen utilization gene functions in A.halodendron.The structures and functional genes of soil bacterial community showed marked sensitivities to different plant species,presenting the potentials for regulating soil carbon and nitrogen cycling. 展开更多
关键词 bacterial taxonomic composition functional gene vegetational type soil carbon and nitrogen 16s rRNA
下载PDF
THE WETLAND TYPES,FUNCTIONS ANDCONSERVATION IN CHINA 被引量:1
13
作者 ZHAO Kui-yi, HE Chi-quan( Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2001年第4期14-19,共6页
ABSTRACT: According to preliminary statistics, there are 9. 4 ×106ha of mire, 8. 0 × 106ha of lake, 2. 1 × 106ha of salt marsh, 2.1 × 107ha of shallow sea (0 - 5m), and 3. 8 × 107ha of paddyfi... ABSTRACT: According to preliminary statistics, there are 9. 4 ×106ha of mire, 8. 0 × 106ha of lake, 2. 1 × 106ha of salt marsh, 2.1 × 107ha of shallow sea (0 - 5m), and 3. 8 × 107ha of paddyfield, their total area amounts to 8. 45× 107ha. Wetland consists of natural wetland system and man-made wetland system. According to hydrology, landform, soil and vegetation etc., natural wetland can be divided into the following types: marine, esturine, riverine, lacustrine, palustrine subsystems. On the basis of the wetland bottom compound, waterlogged state and vegetation forms, it can be subdivided into 26 wetland classes. Man-made wetland can be subdivided into 4 wetland classes. Wetland is a unique landscape in the earth and one of the most important living environment with rich resources and many functions. At present, 262 different types of Wetland Natural Reserves have been established in China, in which 7 Wetland Nature Reserves have been listed in international important wetlands of The Wetland 展开更多
关键词 WETLAND type WETLAND function WETLAND CONsERVATION China’s WETLAND
下载PDF
Hyperbolic Fibonacci and Lucas Functions, “Golden” Fibonacci Goniometry, Bodnar’s Geometry, and Hilbert’s Fourth Problem—Part III. An Original Solution of Hilbert’s Fourth Problem 被引量:3
14
作者 Alexey Stakhov Samuil Aranson 《Applied Mathematics》 2011年第3期283-293,共11页
This article refers to the “Mathematics of Harmony” by Alexey Stakhov [1], a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries—New Geom... This article refers to the “Mathematics of Harmony” by Alexey Stakhov [1], a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries—New Geometric Theory of Phyl-lotaxis (Bodnar’s Geometry) and Hilbert’s Fourth Problem based on the Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci -Goniometry ( is a given positive real number). Although these discoveries refer to different areas of science (mathematics and theoretical botany), however they are based on one and the same scien-tific ideas—The “golden mean,” which had been introduced by Euclid in his Elements, and its generalization—The “metallic means,” which have been studied recently by Argentinian mathematician Vera Spinadel. The article is a confirmation of interdisciplinary character of the “Mathematics of Harmony”, which originates from Euclid’s Elements. 展开更多
关键词 Euclid’s Fifth Postulate Lobachevski’s GEOMETRY HYPERBOLIC GEOMETRY Phyllotaxis Bodnar’s GEOMETRY Hilbert’s FOURTH Problem the “Golden” and “Metallic” Means Binet Formulas HYPERBOLIC FIBONACCI and Lucas functions Gazale Formulas “Golden” FIBONACCI -Goniometry
下载PDF
Comprehensive form of solution for Lamb's dynamic problem expressed by Green's functions 被引量:1
15
作者 丁伯阳 徐庭 +1 位作者 陈军 欧阳明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第12期1543-1552,共10页
By the analysis for the vectors of a wave field in the cylindrical coordinate and Sommerfeld's identity as well as Green's functions of Stokes' solution pertaining the conventional elastic dynamic equation, the res... By the analysis for the vectors of a wave field in the cylindrical coordinate and Sommerfeld's identity as well as Green's functions of Stokes' solution pertaining the conventional elastic dynamic equation, the results of Green's function in an infinite space of an axisymmetric coordinate are shown in this paper. After employing a supplementary influence field and the boundary conditions in the free surface of a senti-space, the authors obtain the solutions of Green's function for Lamb's dynamic problem. Besides, the vertical displacement uzz and the radial displacement urz can match Lamb's previous results, and the solutions of the linear expansion source u^r and the linear torsional source uee are also given in the paper. The authors reveal that Green's function of Stokes' solution in the semi-space is a comprehensive form of solution expressing the dynamic Lamb's problem for various situations. It may benefit the investigation of deepening and development of Lamb's problems and solution for pertinent dynamic problems conveniently. 展开更多
关键词 Lamb's problem Green's function comprehensive form of solution
下载PDF
<i>Ratanasampil</i>(Tibetan Medicine, RNSP) Reduces <i>β</i>-Amyloid Protein (Aβ) and Pro-Inflammatory Factor Levels and Improves Cognitive Functions in Mild-to-Moderate Alzheimer’s Disease (AD) Patients Living at High Altitude 被引量:5
16
作者 Aiqin Zhu Aiqi Xi +7 位作者 Guofeng Li Yinglan Li Baoxia Liao Xing Zhong Jingping Zhou Sonqin Gu Meihua Yu Yide Chu 《Journal of Behavioral and Brain Science》 2012年第1期82-91,共10页
Ratanasampil (RNSP) is a traditional Tibetan medicine used for the treatment of stroke and cerebrovascular diseases. Previous discoveries that RNSP can reduce β-amyloid protein levels and increase learning and memory... Ratanasampil (RNSP) is a traditional Tibetan medicine used for the treatment of stroke and cerebrovascular diseases. Previous discoveries that RNSP can reduce β-amyloid protein levels and increase learning and memory in Alzheimer’s mouse models (Tg2576) led us to investigate whether RNSP can improve cognitive functions in Alzheimer’s patients. In this study, 146 AD patients living in Qinghai province received either one gram or 0.33 gram daily of RNSP for 16 weeks. Placebo patients received Piracetam. Serum Aβ40 and Aβ42 levels were measured at the beginning of the study and after 4 and 16 weeks of treatment. Compared to the same group before treatment, MMSE scores, ADAS-cog scores and ADL scores were significantly improved (p 0.05, p > 0.05). After 16-week treatment, serum TNF-α, IL-1β, IL-6 and Aβ42 levels were significantly decreased (p < 0. 01) in the high-dose RNSP group, whereas no significant differences were found in the low-dose and placebo groups. The Aβ42/Aβ40 ratio was significantly decreased after 4-week and 16-week treatment in the high-dose RNSP group (p < 0. 05, p < 0.01). Furthermore, serum Aβ42 concentrations had a strong positive correlation with TNF-α, IL-1β and IL-6 levels. There were no observable adverse effects in either treatment or control groups. We conclude that further clinical trials of RNSP in Alzheimer disease are warranted. 展开更多
关键词 Ratanasampil (RNsP Tibetan Medicine) Alzheimer’s Disease Β-AMYLOID Peptide Aβ42/Aβ40 Ratio PRO-INFLAMMATORY Factors Cognitive function
下载PDF
Evaluation of Generalized Error Function via Fast-Converging Power Series
17
作者 Serdar Beji 《Advances in Pure Mathematics》 2024年第6期495-514,共20页
A generalized form of the error function, Gp(x)=pΓ(1/p)∫0xe−tpdt, which is directly associated with the gamma function, is evaluated for arbitrary real values of p>1and 0x≤+∞by employing a fast-converging power... A generalized form of the error function, Gp(x)=pΓ(1/p)∫0xe−tpdt, which is directly associated with the gamma function, is evaluated for arbitrary real values of p>1and 0x≤+∞by employing a fast-converging power series expansion developed in resolving the so-called Grandi’s paradox. Comparisons with accurate tabulated values for well-known cases such as the error function are presented using the expansions truncated at various orders. 展开更多
关键词 Generalized Error function Gamma function Grandi’s Paradox Fast-Converging Power series
下载PDF
A hybrid method integrating Green's function Monte Carlo and projected entangled pair states
18
作者 He-Yu Lin Rong-Qiang He +1 位作者 Yibin Guo Zhong-Yi Lu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期75-81,共7页
This paper introduces a hybrid approach combining Green’s function Monte Carlo(GFMC)method with projected entangled pair state(PEPS)ansatz.This hybrid method regards PEPS as a trial state and a guiding wave function ... This paper introduces a hybrid approach combining Green’s function Monte Carlo(GFMC)method with projected entangled pair state(PEPS)ansatz.This hybrid method regards PEPS as a trial state and a guiding wave function in GFMC.By leveraging PEPS’s proficiency in capturing quantum state entanglement and GFMC’s efficient parallel architecture,the hybrid method is well-suited for the accurate and efficient treatment of frustrated quantum spin systems.As a benchmark,we applied this approach to study the frustrated J_(1)–J_(2) Heisenberg model on a square lattice with periodic boundary conditions(PBCs).Compared with other numerical methods,our approach integrating PEPS and GFMC shows competitive accuracy in the performance of ground-state energy.This paper provides systematic and comprehensive discussion of the approach of our previous work[Phys.Rev.B 109235133(2024)]. 展开更多
关键词 projected entangled pair states Green’s function Monte Carlo frustrated J_(1)-J_(2)Heisenberg model
下载PDF
Hyperbolic Fibonacci and Lucas Functions, “Golden” Fibonacci Goniometry, Bodnar’s Geometry, and Hilbert’s Fourth Problem—Part II. A New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) 被引量:2
19
作者 Alexey Stakhov Samuil Aranson 《Applied Mathematics》 2011年第2期181-188,共8页
This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries–New ... This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries–New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) and Hilbert’s Fourth Problem based on the Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci λ-Goniometry (λ > 0 is a given positive real number). Although these discoveries refer to different areas of science (mathematics and theoretical botany), however they are based on one and the same scientific ideas-the “golden mean,” which had been introduced by Euclid in his Elements, and its generalization—the “metallic means,” which have been studied recently by Argentinian mathematician Vera Spinadel. The article is a confirmation of interdisciplinary character of the “Mathematics of Harmony”, which originates from Euclid’s Elements. 展开更多
关键词 Euclid’s Fifth Postulate Lobachevski’s GEOMETRY HYPERBOLIC GEOMETRY PHYLLOTAXIs Bodnar’s GEOMETRY Hilbert’s Fourth Problem The “Golden” and “Metallic” Means Binet Formukas HYPERBOLIC FIBONACCI and Lucas functions Gazale Formulas “Golden” FIBONACCI λ-Goniometry
下载PDF
Refinements to Hadamard’s Inequality for Log-Convex Functions 被引量:1
20
作者 Waadallah T. Sulaiman 《Applied Mathematics》 2011年第7期899-903,共5页
In this paper we show that a log-convex function satisfies Hadamard's inequality, as well as we give an extension for this result in several directions.
关键词 Log-Convex functions Hadamard’s INEQUALITY INTEGRAL INEQUALITY
下载PDF
上一页 1 2 210 下一页 到第
使用帮助 返回顶部