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东疆春季一次大风沙尘天气成因分析
The Cause Analysis of a Windy Dust Weather in Spring in Eastern Xinjiang
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Climate Change Research Letters (CCRL) , 2016, DOI: 10.12677/CCRL.2016.52010
Abstract:
本文利用常规观测资料、数值预报和自动气象站资料,对东疆地区2015年春季一次大风沙尘天气进行了分析,结果表明:此次大风沙尘天气是高空低压槽、地面冷锋和冷高压移动过境所致,强的热力和动力条件是大风沙尘形成和维持的主要因素,大风沙尘发生的区域,大气处于高能不稳定状态,涡度、散度、总温度都有明显的指示意义。
Using the conventional observation data, numerical prediction and automatic weather stations data, this paper analyzed the windy dust weather in spring of 2015 in Eastern Xinjiang. The results showed that: the windy dust resulted from the upper low trough, surface cold front and moving cold high pressure, strong thermal and dynamic conditions were the main factors for the formation and maintenance of windy dust. In occurred area, the atmosphere is in a state of high energy. Vorticity, divergence and total temperature have obvious implications.
非线性差分方程Xn=qx-1n-1+pxn-2解的性态
Properties of the Solution of the Nonlinear Difference Equation Xn=qx-1n-1+pxn-2
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, 宇辰
Pure Mathematics (PM) , 2015, DOI: 10.12677/PM.2015.55033
Abstract:
本文给出了差分方程Xn=qx-1n-1+pxn-2解的有界性的一个充分性条件,同时探讨了解了收敛性及二周期点存在的充分必要条件。
In this paper, we obtain one sufficient condition of the boundedness of equation X
n=qx-1n-1+pxn-2 , and discuss the convergence of the solution of equation and the sufficient and necessary condition of existence of the periodic point with period 2 of the equation.
提高自钻式锚杆抗拔力的技术措施
Technical Measures of Improving Self-Drilling Anchor Pullout Resistance
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小冬
Hans Journal of Civil Engineering (HJCE) , 2013, DOI: 10.12677/HJCE.2013.21012
Abstract:
由于受地层条件等诸因素的影响,自钻式锚杆抗拔力达不到设计要求的情况时有出现。如何提高自钻式锚杆抗拔力是采用自钻式锚杆支护时必须考虑的一个重要问题。以承德钢厂烧结机改造工程5#边坡(VK0 + 226.94-K0 + 270.64)支护为例,介绍了影响自钻式锚杆抗拔力的因素,主要从钻进成孔工艺、清孔方法、钻进技术参数选择、注浆控制等方面论述了提高自钻式锚杆抗拔力的技术措施。
Due to the influence of the geological conditions and other factors, pullout resistance of self-drilling anchor can’t achieve the design requirements appearing from time to time. How to improve the self-drilling anchor pullout resistance is an important question that must be considered in the self-drilling anchor supporting. Take Chengde Steel sintering machine renovation project of No.5 slope (VK0 + 226.94-K0 + 270.64) supporting as an example, describing the factors that affecting the self-drilling anchor pullout resistance, discussing technical measures to improve the self- drilling anchor pullout resistance mainly from drilling into the hole process, hole cleaning method, drilling technology parameter selection, grouting control and so on.
并行求解抛物型偏微分方程的一种新ASE-I格式
A New ASE-I Method for Solving Parabolic Equations
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王栋,
Advances in Applied Mathematics (AAM) , 2013, DOI: 10.12677/AAM.2013.21003
Abstract:

通过古典显、隐格式和Saul’yev非对称格式,本文构造了一种并行求解抛物型偏微分方程的一种新的ASE-I格式。这种新的差分格式兼具绝对稳定性和高度并行性,并且分段更加灵活,从而这种新的差分格式应用更加广泛。本文给出这种新的差分格式的数学形式,分析了稳定性并得出了稳定性定理。最后通过数值算例验证了这种新ASE-I格式的稳定性和精确性,数值试验结果和理论分析相符合。
In this paper, I construct a new ASE-I scheme for solving parabolic partial differential equations in parallel through classical explicit-implicit format and the Saul’yev asymmetric formats. This method is absolutely parallel and stable, and the sub-sections are more flexible, so the scheme is more convenient to apply to solve parabolic partial differential equations. In this paper, we list the mathematical form of this finite difference scheme, analyze the stability of the scheme, and verify the stability and accuracy of this scheme through numerical experiments. The results of numerical experiments are consistent with the theoretical analysis.

二维非定常Navier-Stokes方程的Euler隐/显格式子格涡旋粘性非协调有限元法
The Euler Implicit/Explicit Schemes with Nonconforming Finite Element Method of Subgrid Eddy Viscosity Type for the 2D Time-Dependent Navier-Stokes Equations
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郭英文, 民富
Advances in Applied Mathematics (AAM) , 2012, DOI: 10.12677/aam.2012.12008
Abstract:

本文研究了二维高雷诺数情形下,非定常不可压Navier-Stokes方程的Euler/显格式子格涡旋粘性非协调有限元方法。隐式处理线性项,避免了时间步长的苛刻限制,显式处理非线性项,使得对所有时间层求解时,系统矩阵为同一常数矩阵;时间项做向后Euler差分离散,空间用C-R非协调有限元逼近,构造子格涡旋粘性有限元方法,克服了在情形下Galerkin有限元方法的不稳定现象。本文改善了稳定性下对时间步长的限制,并给出了不依赖粘性系数的速度和压力误差估计。

In this paper, an Euler implicit/explicit scheme with nonconforming finite element method of subgrid eddy viscosity type for solving the 2D nonstationary incompressible Navier-Stokes equations under high Reynolds number  is considered. The implicit/explicit scheme which is implicit for the linear terms and explicit for the nonlinear term, avoids the severely restricted time step size from stability requirement and results in a linear system with a same constant matrix at each level of time. The backward Euler scheme is used for time discretization. Crouzeix-Raviart nonconforming finite element approximation is used for the velocity and pressure field with the subgrid eddy viscosity technique, to cope with usual instabilities caused by Galerkin finite element methods. This paper also improved the restricted time step size which under stable conditions and given error estimates of velocity and pressure which independent on the viscosity .

 

基于MATLAB的高压直流输电系统的仿真
The Simulation of HVDC Transmission System Based on MATLAB
 [PDF]

媛硕
Advances in Energy and Power Engineering (AEPE) , 2013, DOI: 10.12677/AEPE.2013.12007
Abstract:
高压直流输电以其传输功率大、线路造价低、控制性能好等优点,在远距离、大功率输电中占有越来越重要的地位,对于高压直流输电系统的研究有重要意义。本文介绍了高压直流输电(HVDC)系统的基本原理,利用Matlab中的SimulinkHVDC系统进行建模和仿真分析。由仿真结果能较准确地观测暂态过程中高压直流输电系统的动态性能。
HVDC (High Voltage Direct Current) transmission takes an increasingly important position in the long distance and high-power transmission project, for its large power of transmission, low cost and good performance advantages of control. The research of high voltage dc transmission system has important significance. The principle of high- voltage direct current (HVDC) transmission system is introduced briefly. Then a simulation model of HVDC system using Matlab/Simulink is established. We can observe the dynamic performance of the high voltage dc transmission system accurately.
北京佛教慈善组织与社会建设的关系探究
The Buddhist Charitable Organizations and Social Construction Relationship
 [PDF]

赵璐,
Advances in Social Sciences (ASS) , 2013, DOI: 10.12677/ASS.2013.22007
Abstract: 社会建设是当代中国现代化建设的主体内容之一,也是重点和难点内容之一。公民社会组织与社会建设的内在关联性目前已经在中国社会学界达成了一定程度的共识。中国民间慈善组织作为公民社会组织的一种形式,内涵着参与社会建设的必然性与必要性。中国民间慈善组织在发展服务社会的公共领域和拓展私人空间方面都发挥了积极的功能。在这些组织中,宗教类慈善公益组织是重要的组成部分,相对于世俗慈善公益组织而言,宗教慈善公益组织除具备一般的公益特性外,还有自己的独特性。以北京仁爱慈善基金会为例,通过对北京仁爱慈善基金会的个案研究,展示宗教慈善公益组织在社会建设方面的探索与实践,以探索北京佛教慈善组织与社会建设的关系,试图为上述必然性与必要性提供一定程度的佐证,以实际地推进社会建设的进程。从理论上看,这种探索对于宗教社会学和社会建设理论也有一定的创新作用。
Social construction is one of the major aspects of modernization construction in contemporary China, as well as one of the difficulties and focuses in this process. To some extent, the sociologists in China have reached a consensus about the internal connection between civil society organization and social con- struction. As a form of civil society organization, the civil charity organization in China embodies the necessity and inevitability of the participation in social construction. The civil charity organization in China plays an important role in the development of public areas of social service and the expansion of private space. Among these organizations, religious charity organization is an integral constituent. Compared with the secular charity organizations, religious organization has its peculiarity, apart from its ordinary cha- racteristics of public welfare. Take Beijing RenAi Charity Organization as an example. From the case study of this organization, the exploration and practice of religious charity organization in social construction are clearly presented. The connection between Beijing Buddhist charity organization and social construction is also explored, which aims to provide evidence to the necessity and inevitability mentioned above, and to practically promote social construction. Theoretically, this exploration has some creative significance to the sociology of religion and the theories of social construction.
三大理论框架下的二语习得研究
Second Language Acquisition Studies under Three Theoretical Frames
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丽娟
Modern Linguistics (ML) , 2014, DOI: 10.12677/ML.2014.22010
Abstract:

本文在介绍普遍语法、认知心理学、社会文化理论的基础上,找到了这三大理论框架与第二语言习得研究的接口,认为二语习得研究如果在这三大理论框架下进行,会更有解释力。最后,我们以普遍语法框架下的结果补语研究为例,介绍了这类二语习得研究的具体操作方法和程序。希望本文的研究可以帮助今后的第二语言习得研究理清思路,提高理论性。
At first, this article introduces three theoretical frames: Universal Grammar, Cognitive Psychology and Sociocultural Theory. Then, we find the interface between these three frames and second language acquisition studies. We claim that if we do second language acquisition research on the basis of these theoretical frames, it will get more persuasive. At last, this article takes a research of Chinese resultatives under the framework of Universal Grammar as an example, and shows me- thod and procedure of second language acquisition studies. We hope this article can help the fol- lowing studies get their thoughts into shape and raise the level of theory.

试论校园足球文化与可持续发展
Research on the Campus Football Culture and Sustainable Development
 [PDF]

崔琳,
Advances in Physical Sciences (APS) , 2015, DOI: 10.12677/APS.2015.32006
Abstract:
构建和谐的校园足球文化,才能培养学生主动参与的兴趣,促进学生体质、心理的健康全面发展。本文以校园足球为研究对象,采用文献资料法,通过中国青少年校园足球官方网站等途径,研究全国校园足球开展现状,构建校园足球文化内容体系,进而探讨校园足球文化建设与校园足球的可持续发展的关联,以期为我国中小学校园足球的健康发展提供参考。
The construction of the harmonious campus football culture to cultivate the students’ active par-ticipation interest promotes students’ physical and mental health development. Taking the campus football as the research object, using the method of literature, by the China Youth campus football official website and other channels, we carry out the research on the current situation of the campus football, construct the campus football culture content system, and explore the relationship between the campus football culture and the sustainable development of the campus football, so as to provide reference for the healthy development of the campus football in primary and middle schools in our country.
一个正定不等式的最佳参数
A Sharp Parameter Value of a Positive Definite Inequality
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贝叶
Advances in Applied Mathematics (AAM) , 2016, DOI: 10.12677/AAM.2016.51006
Abstract: 本文解决了参考文献[1]中提出的一个公开问题,用初等方法确定了一个正定不等式成立的最佳参数值。
In this paper, we solved an open problem proposed in [1]. We get a sharp parameter value of a positive definite inequality by elementary method.
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