一种基于虚拟页地址映射的NAND Flash管理算法

本文提出了一种基于虚拟页地址映射的NAND Flash管理算法.该算法通过定义坏块表、对应表等结构，以及设计的坏块替换策略和虚拟页地址到实际物理页地址的转换算法，实现上层软件采用虚拟地址对NAND Flash的无坏块连续页地址访问.该算法是一种高效的地址映射算法，能高效地对数据进行索引，占用SRAM空间较少，使系统达到高性能，并使得闪存使用的更加稳定持久.     

一类拟线性椭圆型方程分歧点的存在性

本文讨论了下面问题的分歧点的存在性：－ｐｘｉ〔（１＋｜ｕ｜２）ｐ２－１ｕｘｉ〕＝μｕ＋ｆ（ｘ，ｕ），ｘ∈ＲＮｕ（ｘ）→０，当｜ｘ｜→＋∞时，ｕ０，μ∈Ｒ１，Ｎ＞ｐ≥２｛证明了μ＝０是上述问题的分歧点。     

一种可伸缩空间机械臂及其应用分析

介绍一种能够完成多关节型空间机械臂所能承担的大部分空间任务 ,而且应用更简便的可伸缩空间机械臂 ,对其空间应用做出了一些设想 ,简单讨论了其应用的一些相关问题 ,肯定了其可行性和实用性。     

含有任意多个椭圆孔弹性板的应力场计算

本文应用弹性力学的复变函数理论,用多保角变换的方法,导出了含有任意多个椭圆孔的无限大弹性板多复变量应力函数的表达式。每个孔的大小、位置和孔边作用的载荷均为任意指定。板的无限远处作用有和坐标轴方向一致的均匀拉压载荷P_x,P_y和均匀剪切载荷P_(xy)。并在孔边进行复Fourier级数展开,用待定系数法确定应力函数的未知系数,从而计算弹性板的应力场。编制了相应的FORTRAN77标准化程序,进行了考题和算例分析,给出了级数的收敛状况和孔边周向应力的分布图。     

Public Attitudes Towards Space Science

Astronomy and space science, including their associated basic research activities, enjoy broad popular backing. People generally support them, and say that they follow their results with interest. This article summarizes some of the detailed results of public surveys in the United States, focusing on popular opinions and attitudes, and the somewhat paradoxical finding that despite being interested and supportive, people are often ignorant about the basic facts. I explore some of the reasons for the popularity of space science, and suggest ways of justifying space science research in the broader context of science research. I argue that vigorous and innovative education and outreach programs are important, and can be made even more effective. This revised version was published online in June 2006 with corrections to the Cover Date.     

Calculation of the transonic dip of airfoils using viscous-inviscid aerodynamic interaction method

A numerical procedure for the calculation of the transonic dip of airfoils in the time domain is presented. A viscous-inviscid aerodynamic interaction method is taken to calculate the unsteady aerodynamic loads. In the present case the integral boundary layer equations are coupled with the Transonic Small Disturbance (TSD) Potential Equation. The coupling between structural motion and aerodynamic loads is carried out using State Space equation. It is solved by State Transition Matrix technique. Results are presented for NACA 64A010 and NLR 7301 airfoils with structural data from Isogai and DLR, respectively. Comparisons show good agreement with other numerical results. Certain deviations of experimental data taken from literature need more insight in the detailed test conditions.     

High energy-density propulsion—reducing the risk to humans in planetary exploration

The potential benefits to humankind of space exploration are tremendous. Space is not only the final frontier but is also the next marketplace. The orbital space above Earth offers tremendous opportunities for both strategic assets and commercial development. The critical obstacle retarding the use of the space around the Earth is the lack of low cost access to orbit. Further out, the next giant leap for mankind will be the human exploration of Mars. Almost certainly within the next 30 years, a human crew will brave the isolation, the radiation, and the lack of gravity to walk on and explore the Red planet. Both of these missions will change the outlook and perspective of every human being on the planet. However, these missions are expensive and extremely difficult. Chemical propulsion has demonstrated an inability to achieve orbit cheaply and is a very high-risk option to accomplish the Mars mission. An alternative solution is to develop a high performance propulsion system. Nuclear propulsion has the potential to be such a system. The question will be whether humanity is willing to take on the challenge.     

关于Nielsen数的注记

通过构造基本群的正规子群，得到有限复迭空间和自映射的提升。并定义了NL数，指出用NL数可以估算自映射的Nielsen数。     

现代激励理论在规范地方政府行为中的作用研究

分析现代激励理论在研究地方政府行为中的作用，并运用现代激励理论提出了规范地方政府经济行为的若干建议。     

波导分支线定向耦合器计算方法

利用模匹配方法和网络理论分析计算了一种卫星天线系统中常用的波导分支线定向耦合器,计算结果与实验结果非常吻合。该方法为波导分支线定向耦合器提供一种有力的设计手段。它可直接用于设计Ku 波段通信卫星天线的波束形成网络,也可以用来设计各种耦合度的波导分支线定向耦合器。