Hardy-Hilbert不等式一个新的改进

研究关于重级数型Hardy-Hilbert不等式改进的问题。通过给出如下形式的权系数的估计式∞研究关于重级数型Hardy-Hilbert不等式改进的问题。通过给出如下形式的权系数的估计式ω(q,n)=∑∞m=11m nnm1q<πsinπp-12np1 2en-q1,q>1,1p q1=1,n∈N,从而得到Hardy-Hilbert不等式的一个新的改进形式∑∞m=1∑∞n=1ambnm n<∑∞n=1πsinπp-12n1p 2en-1qanp1p∑∞n=1πsinπp-12n1q 2en-1pbnq1q。     

地下圆形衬砌隧道对沿线地震动的影响(Ⅰ):级数解

利用波函数展开法，给出了地下圆形衬砌隧道对入射平面P波和SV波散射问题的一个级数解答，当衬砌与半空间介质相同时，该解答退化为文献中的无衬砌隧道的解答。级数解答为进一步定量研究隧道对入射平面P波和SV波的放大作用以及入射波长、入射角度、隧道直径和衬砌刚度等参数对隧道沿线地震动的影响奠定了理论基础。     

基于静地特性的GEO带目标混合函数型星历表征设计

地球同步轨道(GEO)卫星带是一类独具高空战略地位的轨道资源.长期以来GEO带编目目标采用双行轨道根数(TLE)和简化常规/深空摄动4模型(SGP4/SDP4)进行通用轨道计算,但该解析算法存在外推精度受限、使用过程复杂、用户难以理解等缺点.本文针对GEO的静地特性,结合经典开普勒根数和多项式-傅里叶级数设计了混合函数型参数星历模型,可用于高精度数值积分轨道的12～24 h轨位拟合和多组星历参数的同步发布,用户计算模型简单.对三颗代表性GEO目标为期一年的星历参数拟合实验表明,1 d拟合均方根(RMS)均值优于20 m;当缩短拟合时长至12 h,拟合精度可优于0.15 m.可为我国空间目标编目库的分级管理提供参考.     

基于改进的突变级数法在复垦区土壤恢复评价中的应用

复垦土壤质量的恢复评价研究主要借鉴土壤质量评价方面的研究。传统的土壤质量评价方法主要有主成分分析法、层次分析法、模糊评价法、熵权法等,这些方法均需要确定权重,而且计算量较大。在突变理论和模糊数学相结合产生出的突变级数法应用到土壤质量评价中,对张集矿区复垦土地进行了评价,并对突变评价值偏高的问题,对其进行改进,通过数值转化的方法来降低评价值。结果表明:经转化后的突变评价值与传统方法(主成分分析法)得到的结果基本一致。并且突变级数法与传统方法相比,具有两个特点:(1)不需要确定权重,减少了人为的主观性问题;(2)突变级数法计算量小,应用较为简便。     

中国地质大学(武汉)王焰新校长指出:地热资源潜力无穷——相当于全世界现产煤炭总发热量的2,000倍

<正>9月12日,"地热资源利用与生态环境保护"主题交流会在内蒙古自治区地质调查院召开。会上,中国地质大学(武汉)王焰新校长指出:地热资源潜力无穷,是新兴的绿色能源。进入21世纪以来,资源和能源问题已成为这个时代人类的重大课题。地热作为一种新资源具有巨大潜力,仅地壳最外层10公里范围内就拥有1,254亿亿亿焦热量,相当于全世界现产煤炭总发热量的2,000倍,地热发电要比水力发电的潜力大100倍,但迄今为止尚未充     

稳恒水波的Fourier近似解研究

A computational method for steady water waves is presented on the basis of potential theory in the physical plane with spatial variables as independent quantities. The finite Fourier series are applied to approximating the free surface and potential function. A set of nonlinear algebraic equations for the Fourier coefficients are derived from the free surface kinetic and dynamic boundary conditions. These algebraic equations are numerically solved through Newton＇s iterative method, and the iterative stability is further improved by a relaxation technology. The integral properties of steady water waves are numerically analyzed, showing that （1） the set-up and the set-down are both non-monotonic quantities with the wave steepness, and （2） the Fourier spectrum of the free surface is broader than that of the potential function. The latter further leads us to explore a modification for the present method by approximating the free surface and potential function through different Fourier series, with the truncation of the former higher than that of the latter. Numerical tests show that this modification is effective, and can notably reduce the errors of the free surface boundary conditions.     

波浪在Jarlan型开孔潜堤上的运动

The wave motion over a submerged Jarlan-type breakwater consisting of a perforated front wall and a solid rear wall was investigated analytically and experimentally. An analytical solution was developed using matched eigenfunction expansions. The analytical solution was confirmed by previously known solutions for single and double submerged solid vertical plates, a multidomain boundary element method solution, and experimental data. The calculated results by the analytical solution showed that compared with double submerged vertical plates, the submerged Jarlan-type perforated breakwater had better wave-absorbing performance and lower wave forces. For engineering designs, the optimum values of the front wall porosity, relative submerged depth of the breakwater, and relative chamber width between front and rear walls were 0.1–0.2, 0.1–0.2, and 0.3–0.4, respectively. Interchanging the perforated front wall and solid rear wall may have no effect on the transmission coefficient. However, the present breakwater with a seaside perforated wall had a lower reflection coefficient.     

基于改进泰勒级数法的总强度磁异常稳健向下延拓

位场向下延拓隶属于经典不适定问题,观测数据中细微的误差在向下延拓过程中都被严重放大,甚至会掩盖真实信息。如何精确地求解总强度磁异常（Bm）在垂直方向的各阶导数,是利用泰勒级数实现稳健向下延拓的关键。为此,本文首先分析了调和函数的相关性质,从理论上证明了Bm为准调和函数的结论,在精确计算各阶垂向导数基础上,提出利用改进泰勒级数实现磁场稳健向下延拓。为降低边界效应对向下延拓计算结果的影响,提出采用半余弦函数对磁场在4个方向上进行平滑扩边处理。通过球体与长方体仿真试验以及航空、船载实测磁场数据对提出方法进行了验证。结论表明,提出的技术方法可实现磁场稳健向下延拓,当观测数据无噪声时,计算结果精度要明显优于现行的FFT法、常规泰勒级数法以及积分-迭代法;当观测数据含有噪声时,本文方法和积分-迭代法计算结果精度相当。     

区域地磁场的连续傅里叶分析建模方法

研究了利用快速傅里叶(FFT)拟合方法建立连续局部地磁场模型,给出了详细的计算方法.建立的局部地磁场表达式是连续的且形式十分简明,有利于地磁匹配辅助惯性导航的实现.最后,给出了某一地磁异常场的实例,用FFT拟合方法建立了局部地磁异常场模型并与传统的Taylor多项式建模方法进行了比较.仿真结果表明,FFT拟合建模方法精...