期刊文献+
共找到1,638篇文章
< 1 2 82 >
每页显示 20 50 100
Relationship between variation of HBV preS function domains and clinical consequences of HBV infection
1
作者 张瑞 顾长海 +2 位作者 赵秋敏 王洪莉 王海涛 《Journal of Medical Colleges of PLA(China)》 CAS 1999年第4期304-306,共3页
Objective:To investigate the relationship between variation of HBV preS genes and clinical consequencesof HBV infection. Methods: We selected 3 groups (3 in each) of HBV infected individuals including those of acutein... Objective:To investigate the relationship between variation of HBV preS genes and clinical consequencesof HBV infection. Methods: We selected 3 groups (3 in each) of HBV infected individuals including those of acuteinfection with complete recovery, chronic HBV carriers and chronic severe hepatitis B. The preS genes were amplified from serum samples with half nested PCR. The PCR products were cloned into M13 vectors and 10 cloneswere randomly selected for each individual and sequenced with standard methods. A total of 90 clones were sequenced and analyzed by DNA homological comparison. Results: The characteristics of the preS genes were significantly different in HBV-infected individuals with different clinical consequences.①As for acute hepatitis B, thepreS function domains were stable and no changes in epitopes for T and B cells were found. ②For chronic HBVcarriers, the function domains within preS proteins showed potentially changes with epitope drifts of T and B cellsbecause of the high variation of HBV preS genes. ③For chronic severe hepatitis B, there were special changes inthe function domains of B cells. The abnormally high immune response would cause severe liver injury in these individuals. Conclusion: This study provides experimental evidence for researches about the possible association ofvariation of preS1/S2 functional regions with clinical consequences. 展开更多
关键词 HBV preS1/S2 function domain CONSEQUENCE VARIATION
下载PDF
SCHWARZ-PICK ESTIMATES FOR BOUNDED HOLOMORPHIC FUNCTIONS ON CLASSICAL DOMAINS 被引量:5
2
作者 刘洋 陈志华 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1377-1382,共6页
In this paper, Schwarz-Pick estimates for high order Fr′echet derivatives of bounded holomorphic functions on three kinds of classical domains are presented. We generalize the early work on Schwarz-Pick estimates of ... In this paper, Schwarz-Pick estimates for high order Fr′echet derivatives of bounded holomorphic functions on three kinds of classical domains are presented. We generalize the early work on Schwarz-Pick estimates of higher order partial derivatives for bounded holomorphic functions on the disk and unit ball. 展开更多
关键词 Schwarz-Pick estimate holomorphic functions classical domains
下载PDF
ON UNIQUENESS OF MEROMORPHIC FUNCTIONS WITH SHARED-SETS IN AN ANGULAR DOMAIN 被引量:4
3
作者 陈省江 林伟川 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期194-206,共13页
In this article, we deal with the uniqueness problems on meromorphic functions sharing two finite sets in an angular domain instead of the whole plane C. In particular, we investigate the uniqueness for meromorphic fu... In this article, we deal with the uniqueness problems on meromorphic functions sharing two finite sets in an angular domain instead of the whole plane C. In particular, we investigate the uniqueness for meromorphic functions of infinite order in an angular domain and obtain some results. Moreover, examples show that the conditions in theorems are necessary. 展开更多
关键词 SHARED-SET UNIQUENESS meromorphic function angular domain infinite order
下载PDF
Fast Evaluation of Time-Domain Green Function for Finite Water Depth 被引量:3
4
作者 滕斌 韩凌 勾莹 《海洋工程:英文版》 2003年第3期417-426,共10页
For computation of large amplitude motions of ships fastened to a dock, a fast evaluation scheme is implemented for computation of the time-domain Green function for finite water depth. Based on accurate evaluation of... For computation of large amplitude motions of ships fastened to a dock, a fast evaluation scheme is implemented for computation of the time-domain Green function for finite water depth. Based on accurate evaluation of the Green function directly, a fast approximation method for the Green function is developed by use of Chebyshev polynomials. Examinations are carried out of the accuracy of the Green function and its derivatives from the scheme. It is shown that when an appropriate number of polynomial terms are used, very accurate approximation can be obtained. 展开更多
关键词 Green function TIME-domain finite water depth
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
5
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
α-CARLESON MEASURE AND BLOCH FUNCTIONS ON BOUNDED SYMMETRIC DOMAINS OF C^n
6
作者 欧阳才衡 《Acta Mathematica Scientia》 SCIE CSCD 1995年第4期385-393,共9页
In this paper we defineα-Carleson measure in the Bergman metric on bounded symmetric domains. Some necessary and sufficient conditions about it and Bloch functions on the domains are given.
关键词 Carleson measure Bloch functions bounded symmetric domains.
下载PDF
A Parallel Global-Local Mixed Evolutionary Algorithm for Multimodal Function Optimization Based on Domain Decomposition 被引量:4
7
作者 Wu Zhi-jian, Tang Zhi-long,Kang Li-shanState Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第S1期253-258,共6页
This paper presents a parallel two-level evolutionary algorithm based on domain decomposition for solving function optimization problem containing multiple solutions. By combining the characteristics of the global sea... This paper presents a parallel two-level evolutionary algorithm based on domain decomposition for solving function optimization problem containing multiple solutions. By combining the characteristics of the global search and local search in each sub-domain, the former enables individual to draw closer to each optima and keeps the diversity of individuals, while the latter selects local optimal solutions known as latent solutions in sub-domain. In the end, by selecting the global optimal solutions from latent solutions in each sub-domain, we can discover all the optimal solutions easily and quickly. 展开更多
关键词 function optimization GT algorithm GLME algorithm evolutionary algorithm domain decomposition
下载PDF
Iterative and adjusting method for computing stream function and velocity potential in limited domains and convergence analysis
8
作者 黎爱兵 张立凤 +1 位作者 臧增亮 张云 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第6期687-700,共14页
The stream function and the velocity potential can be easily computed by solving the Poisson equations in a unique way for the global domain. Because of the var- ious assumptions for handling the boundary conditions, ... The stream function and the velocity potential can be easily computed by solving the Poisson equations in a unique way for the global domain. Because of the var- ious assumptions for handling the boundary conditions, the solution is not unique when a limited domain is concerned. Therefore, it is very important to reduce or eliminate the effects caused by the uncertain boundary condition. In this paper, an iterative and ad- justing method based on the Endlich iteration method is presented to compute the stream function and the velocity potential in limited domains. This method does not need an explicitly specifying boundary condition when used to obtain the effective solution, and it is proved to be successful in decomposing and reconstructing the horizontal wind field with very small errors. The convergence of the method depends on the relative value for the distances of grids in two different directions and the value of the adjusting factor. It is shown that applying the method in Arakawa grids and irregular domains can obtain the accurate vorticity and divergence and accurately decompose and reconstruct the original wind field. Hence, the iterative and adjusting method is accurate and reliable. 展开更多
关键词 limited domain stream function velocity potential iteration and adjust-ment CONVERGENCE
下载PDF
Positively Worded Subscale Score of the Perceived Stress Scale Is Associated with Cognitive Domain Function
9
作者 Julie M. Jiang Elizabeth K. Seng +2 位作者 Molly E. Zimmerman Mimi Kim Richard B. Lipto 《Journal of Behavioral and Brain Science》 2017年第7期311-324,共14页
Objectives: To examine the cross-sectional associations of the separate subscales of the Perceived Stress Scale (PSS) and tests measuring cognitive domains in older adults. Methods: 897 adults over the age of 70 free ... Objectives: To examine the cross-sectional associations of the separate subscales of the Perceived Stress Scale (PSS) and tests measuring cognitive domains in older adults. Methods: 897 adults over the age of 70 free of amnestic mild cognitive impairment and dementia and enrolled in the Einstein Aging Study made up the study sample. The PSS-14 was used to measure stress. Three cognitive domains (language, episodic memory, and frontal-executive) had previously been found using principle component analysis. Linear regression analyses were used to determine the relationship between the PSS subscales and cognitive domain function. Results: The study sample had a mean age of 79.1 years and 62.8% were female. Bivariate correlations show that the PSS-14 positively worded subscale of the PSS (PSS-PW) was significantly associated with all three cognitive domains (language: r = -0.15, p < 0.001;episodic memory: r = -0.16, p < 0.001;frontal-executive: r = -0.21, p <0.001) while the negatively worded subscale of the PSS (PSS-NW) was not significantly associated with any cognitive domain. In linear regression analyses adjusted for age, white race, gender, years of education, and depressive symptoms, the PSS-PW remained significantly associated with each of the cognitive domains. The PSS-NW was not associated with any cognitive domains in any model. The PSS-14 was significantly associated with language and episodic memory, but not the frontal-executive domain. Conclusion: Worse PSS-PW scores are associated with reduced cognitive function in the executive, memory, and language domains in nondemented older adults. The PSS-PW subscale correlated better with cognitive function than the overall PSS-14. Future research should evaluate the temporality of the association and if stress reduction therapies improve cognitive performance. 展开更多
关键词 PERCEIVED STRESS SCALE Cognitive domain function CROSS-SECTIONAL PERCEIVED STRESS SCALE Subscales
下载PDF
DUAL FUNCTIONALS OF SAID-BZIER TYPE GENERALIZED BALL BASES OVER TRIANGLE DOMAIN AND THEIR APPLICATION
10
作者 Wu Hongyi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第1期96-106,共11页
A family of Said-Bézier type generalized Ball (SBGB) bases and surfaces with a parameter H over triangular domain is introduced,which unifies Bézier surface and Said-Ball surface and includes several inter... A family of Said-Bézier type generalized Ball (SBGB) bases and surfaces with a parameter H over triangular domain is introduced,which unifies Bézier surface and Said-Ball surface and includes several intermediate surfaces. To convert different bases and surfaces,the dual functionals of bases are presented. As an application of dual functionals,the subdivision formulas for surfaces are established. 展开更多
关键词 Bézier basis Said-Bézier type generalized Ball (SBGB) basis triangular domain dual functional subdivision formula.
下载PDF
Model-Driven Derivation of Domain Functional Requirements from Use Cases 被引量:1
11
作者 Jianmei Guo Zheying Zhang Yinglin Wang 《Journal of Software Engineering and Applications》 2010年第9期875-881,共7页
Domain analysis is essential to core assets development in software product line engineering. Most existing approaches, however, depend on domain experts’ experience to analyze the commonality and variability of syst... Domain analysis is essential to core assets development in software product line engineering. Most existing approaches, however, depend on domain experts’ experience to analyze the commonality and variability of systems in a domain, which remains a manual and intensive process. This paper addresses the issue by proposing a model-driven approach to automating the domain requirements derivation process. The paper focuses on the match between the use cases of existing individual products and the domain functional requirements of a product line. By introducing a set of linguistic description dimensions to differentiate the sub-variations in a use case, the use case template is extended to model variability. To this end, a transformation process is formulated to sustain and deduce the information in use cases, and to match it to domain functional requirements. This paper also presents a prototype which implements the derivation as a model transformation described in a graphical model transformation language MOLA. This approach complements existing domain analysis techniques with less manual operation cost and more efficiency by automating the domain functional requirements development. 展开更多
关键词 Software Product LINES domain Analysis Model TRANSFORMATION Use CASES functionAL Requirements
下载PDF
Domain boundaries in silicene:Density functional theory calculations on electronic properties
12
作者 肖红君 张礼智 +1 位作者 杜世萱 高鸿钧 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期116-119,共4页
By using density functional theory(DFT)-based first-principles calculations, the structural stability and electronic properties for two kinds of silicene domain boundaries, forming along armchair edge and zigzag edge,... By using density functional theory(DFT)-based first-principles calculations, the structural stability and electronic properties for two kinds of silicene domain boundaries, forming along armchair edge and zigzag edge, have been investigated. The results indicate that a linkage of tetragonal and octagonal rings(4|8) appears along the armchair edge, while a linkage of paired pentagonal and octagonal rings(5|5|8) appears along the zigzag edge. Different from graphene, the buckling properties of silicene lead to two mirror symmetrical edges of silicene line-defect. The formation energies indicate that the 5|5|8 domain boundary is more stable than the 4|8 domain boundary. Similar to graphene, the calculated electronic properties show that the 5|5|8 domain boundaries exhibit metallic properties and the 4|8 domain boundaries are half-metal.Both domain boundaries create the perfect one-dimensional(1D) metallic wires. Due to the metallic properties, these two kinds of nanowires can be used to build the silicene-based devices. 展开更多
关键词 domain boundaries SILICENE line defect density functional theory
下载PDF
Evaluation of strongly singular domain integrals for internal stresses in functionally graded materials analyses using RIBEM
13
作者 Hai-Feng Peng Jian Liu +1 位作者 Qiang-Hua Zhu Ch.Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第6期917-926,共10页
An accurate evaluation of strongly singular domain integral appearing in the stress representation formula is a crucial problem in the stress analysis of functionally graded materials using boundary element method.To ... An accurate evaluation of strongly singular domain integral appearing in the stress representation formula is a crucial problem in the stress analysis of functionally graded materials using boundary element method.To solve this problem,a singularity separation technique is presented in the paper to split the singular integral into regular and singular parts by subtracting and adding a singular term.The singular domain integral is transformed into a boundary integral using the radial integration method.Analytical expressions of the radial integrals are obtained for two commonly used shear moduli varying with spatial coordinates.The regular domain integral,after expressing the displacements in terms of the radial basis functions,is also transformed to the boundary using the radial integration method.Finally,a boundary element method without internal cells is established for computing the stresses at internal nodes of the functionally graded materials with varying shear modulus. 展开更多
关键词 Stress integral equations functionally graded materials Strongly singular domain integral Singularity separation technique Radial integration method
下载PDF
基于原子/分子团簇结构的材料与器件制造
14
作者 邵金友 宋凤麒 +8 位作者 李祥明 杨扬 谭新峰 詹东平 金明尚 孙頔 付德君 谭元植 许辉 《中国科学基金》 CSCD 北大核心 2024年第1期115-131,共17页
原子/分子团簇是物质结构的一种新形态,具有独特的本征性质。从原子/分子团簇到器件的跨尺度制造,将为国防高端装备和新兴电子等产业发展带来深刻变革。团簇的多物质构效关系、宏量制造、团簇结构跨尺度构筑以及团簇器件的高性能制造等... 原子/分子团簇是物质结构的一种新形态,具有独特的本征性质。从原子/分子团簇到器件的跨尺度制造,将为国防高端装备和新兴电子等产业发展带来深刻变革。团簇的多物质构效关系、宏量制造、团簇结构跨尺度构筑以及团簇器件的高性能制造等是原子/分子团簇器件制造的关键发展方向,主导着从原子到产品制造的发展历程。把握这些发展背后的重要机遇,将有助于占领原子级制造研究的制高点,引领原子级制造方法的变革。本文从团簇新材料的宏量制造、新型功能器件的原子/分子团簇构筑、团簇—器件的跨尺度制造工艺和装备等三个方面概括了原子/分子团簇与器件制造领域的主要研究进展,总结了原子/分子团簇与器件领域的关键科学问题及面临的挑战,并对其未来发展方向和发展战略给出了建议。 展开更多
关键词 原子/分子团簇 功能器件 定域组装 异质/异构界面 构效关系 宏量制造
下载PDF
UNIQUENESS OF MEROMORPHIC FUNCTIONS WHOSE NONLINEAR DIFFERENTIAL POLYNOMIALS SHARE ONE VALUE OR HAVE THE SAME FIXED POINTS IN AN ANGULAR DOMAIN 被引量:1
15
作者 李效敏 仪洪勋 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期593-609,共17页
In this article, we study the uniqueness question of nonconstant meromorphic functions whose nonlinear differential polynomials share 1 or have the same fixed points in an angular domain. The results in this article i... In this article, we study the uniqueness question of nonconstant meromorphic functions whose nonlinear differential polynomials share 1 or have the same fixed points in an angular domain. The results in this article improve Theorem 1 of Yang and Hua [26], and improve Theorem 1 of Fang and Qiu [6]. 展开更多
关键词 Meromorphic functions shared values singular directions uniqueness theo-reins in the angular domain
下载PDF
NEW SUBCLASS OF ANALYTIC FUNCTIONS IN CONICAL DOMAIN ASSOCIATED WITH A LINEAR OPERATOR
16
作者 Muhammed ARIF Shahid MAHMOOD +1 位作者 Janusz SOKOL Jacek DZIOK 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期704-716,共13页
The main object of the present paper is to investigate a number of useful properties such as inclusion relations, distortion bounds, coefficient estimates, subordination results, the Fekete-Szego problem and some othe... The main object of the present paper is to investigate a number of useful properties such as inclusion relations, distortion bounds, coefficient estimates, subordination results, the Fekete-Szego problem and some other for a new subclass of analytic functions, which are defined here by means of linear operator. Relevant connections of the results presented here with those obtained in earlier works are also pointed out. 展开更多
关键词 analytie functions SUBORDINATION functions with positive real part linear operators conic domains
下载PDF
数据-知识融合的水利工程建设安全风险灰色因子分解机预测模型 被引量:2
17
作者 张可 张政 金伟 《水利水电技术(中英文)》 北大核心 2024年第1期134-143,共10页
【目的】已有的数据驱动的水利工程建设安全风险预测方法对领域知识的挖掘和利用不足,预测结果的准确性和可解释性有待进一步提高。为了构建数据-知识融合的水利工程建设安全风险预测模型,【方法】将灰色聚类与因子分解机相结合,提出了... 【目的】已有的数据驱动的水利工程建设安全风险预测方法对领域知识的挖掘和利用不足,预测结果的准确性和可解释性有待进一步提高。为了构建数据-知识融合的水利工程建设安全风险预测模型,【方法】将灰色聚类与因子分解机相结合,提出了一种融合领域知识的灰色因子分解机。首先,引入基于可能度函数的灰色聚类表征水利工程建设领域专家有关安全风险的先验知识。然后,将先验知识以参数的形式嵌入到因子分解机中,构建出数据-知识融合的灰色因子分解机。最后,基于随机梯度下降构造模型参数的求解算法,并结合实例对模型的有效性进行验证。【结果】实例应用结果显示,与传统因子分解机相比,灰色因子分解机的准确率、精确率、召回率和F_(1)值均得到了不同程度的提升。与支持向量机、深度因子分解机等其他基准模型相比,灰色因子分解机同样具有更好的预测性能。【结论】这表明,数据-知识融合驱动的灰色因子分解机模型能够更加准确地预测出安全风险,从而为水利工程建设安全风险管控提供更好的决策支持。 展开更多
关键词 因子分解机 风险交互 领域知识 可能度函数 灰色聚类 影响因素
下载PDF
基于资源感知的多域服务功能链编排成本优化
18
作者 徐九韵 脱颖超 +1 位作者 赵耀鹏 李世宝 《计算机系统应用》 2024年第5期178-186,共9页
网络功能虚拟化技术的兴起使得实例化为服务功能链(SFC)的网络服务能够共享基底网络,缓解了传统网络体系结构僵化的问题.然而,网络中大量服务请求给多域SFC编排带来了新的挑战.首先由于域内网络资源信息及内部策略的保密性,使得多域SFC... 网络功能虚拟化技术的兴起使得实例化为服务功能链(SFC)的网络服务能够共享基底网络,缓解了传统网络体系结构僵化的问题.然而,网络中大量服务请求给多域SFC编排带来了新的挑战.首先由于域内网络资源信息及内部策略的保密性,使得多域SFC的编排更为复杂.其次多域SFC编排要确定最佳候选编排域集,先前的研究较少考虑域间负载的均衡性,对服务接受率造成了消极影响.此外跨网络域编排服务请求对服务的成本和响应时间提出了更严格的要求.为解决上述挑战,在本文中,我们首先针对多域网络隐私性需求,提出了域级图的构造方法;然后基于域间负载均衡提出了域权重的计算方法进行SFC编排域的选择;最后,针对多域网络成本和响应时间需求,提出编排算法.实验结果表明,提出的算法有效地权衡了平均服务成本和接受率,并且在服务平均响应时间方面也得到了优化. 展开更多
关键词 网络功能虚拟化 多域网络 服务功能链编排 资源感知编排 成本优化
下载PDF
一类华罗庚域的Bergman核函数的显式表达
19
作者 程晓亮 付瑀 《华南师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期105-109,共5页
在任意不可约有界圆型齐性域上考虑一类华罗庚域E(q 1,…,q m,Ω;p 1,…,p m),其中Ω是指任意不可约有界圆型齐性域,q 1,…,q m都是自然数,m,p 1,…,p m都是正整数,N(Z,Z)是Ω的一般范数。利用完备正交函数系和多元极坐标变换,给出了该... 在任意不可约有界圆型齐性域上考虑一类华罗庚域E(q 1,…,q m,Ω;p 1,…,p m),其中Ω是指任意不可约有界圆型齐性域,q 1,…,q m都是自然数,m,p 1,…,p m都是正整数,N(Z,Z)是Ω的一般范数。利用完备正交函数系和多元极坐标变换,给出了该域的Bergman核函数的显式表达。 展开更多
关键词 BERGMAN核函数 semi-Reinhardt域 华罗庚域
下载PDF
三维时域自由面格林函数法的时域绕射力计算研究
20
作者 鲁江 张楠 +1 位作者 张新曙 顾民 《船舶力学》 EI CSCD 北大核心 2024年第7期981-994,共14页
船舶工业CAE软件势流求解器的开发对势流计算方法的可靠性提出要求,本文针对三维时域面元法开展绕射力计算研究。首先引入三维时域自由面格林函数,其瞬时项的求解采用Hess&Smith方法,记忆项的求解采用Beck团队的方法;其次,推导出全... 船舶工业CAE软件势流求解器的开发对势流计算方法的可靠性提出要求,本文针对三维时域面元法开展绕射力计算研究。首先引入三维时域自由面格林函数,其瞬时项的求解采用Hess&Smith方法,记忆项的求解采用Beck团队的方法;其次,推导出全浪向绕射力脉冲函数法编程所用的数学表达式;然后,采用分布源模型求解源强和速度势,并采用压力直接积分法求出时域绕射力;最后,针对Wigley I船型开展绕射力和FK力计算,并与公开的试验和计算结果进行对比,验证本文方法的可靠性。本文方法和代码可用于船舶工业CAE软件势流求解器和波浪中船舶非线性失稳运动预报。 展开更多
关键词 三维时域面元法 三维时域格林函数 绕射力 船舶CAE自主软件
下载PDF
上一页 1 2 82 下一页 到第
使用帮助 返回顶部