期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
可调节经线收敛度和经纬线间隔的伪圆柱投影 被引量:3
1
作者 钟业勋 胡毓钜 《海洋测绘》 2011年第3期8-11,共4页
令纬度φj转换为ψj后,中央经线方程用一个ψj的7次幂方程表示,中央经线方程的系数关联着纬线间隔。令经度λi转换为iξ后,赤道方程用一个iξ的7次幂方程表示,赤道方程的系数关联着经线间隔。经线的收敛度由经线方程的收敛系数调节。由... 令纬度φj转换为ψj后,中央经线方程用一个ψj的7次幂方程表示,中央经线方程的系数关联着纬线间隔。令经度λi转换为iξ后,赤道方程用一个iξ的7次幂方程表示,赤道方程的系数关联着经线间隔。经线的收敛度由经线方程的收敛系数调节。由此构建可调节经线收敛度和经纬线间隔的伪圆柱投影。用一实例阐释了投影的设计过程和方法。 展开更多
关键词 伪圆柱投影 经线收敛度 中央经线方程 赤道方程 经线间隔 纬线间隔 变形计算
下载PDF
圆柱与伪圆柱组合投影
2
作者 童新华 钟业勋 《海南师范大学学报(自然科学版)》 CAS 2012年第1期32-35,共4页
根据圆柱投影和伪圆柱投影的变形分布和互补性,提出了圆柱与伪圆柱组合投影概念.推导了中央经线方程,赤道方程和伪圆柱投影的非中央经线方程.通过系数K1,K2和K3分别调节纬线间隔、经线间隔和伪圆柱投影的非中央经线收敛度.用系数K4确保... 根据圆柱投影和伪圆柱投影的变形分布和互补性,提出了圆柱与伪圆柱组合投影概念.推导了中央经线方程,赤道方程和伪圆柱投影的非中央经线方程.通过系数K1,K2和K3分别调节纬线间隔、经线间隔和伪圆柱投影的非中央经线收敛度.用系数K4确保伪圆柱投影的经线与接合纬线正交.用一实例阐释了圆柱与伪圆柱组合投影的设计程序和方法.本例中,在南纬60°到北纬60°之间,面积比在1.5以下,最大角度变形在15°以下.这投影适于用作小比例尺世界地图的数学基础. 展开更多
关键词 圆柱投影 伪圆柱投影 组合投影 中央经线方程 赤道方程 接合纬线 变形
下载PDF
Motion of Relativistic Strings on the Equatorial Plane in the Schwarzschild Space-Time
3
作者 孔德兴 李晓燕 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第1期80-86,共7页
In this paper, we investigate the basic equations of the motion for relativistic strings on the equatorial plane in the Schwarzsehild space-time, discuss smooth solutions of the motion equations for closed strings, an... In this paper, we investigate the basic equations of the motion for relativistic strings on the equatorial plane in the Schwarzsehild space-time, discuss smooth solutions of the motion equations for closed strings, and obtain some interesting physical results. 展开更多
关键词 Schwarzschild space-time relativistic string black hole event horizon
原文传递
Nonlinearly Coupled KdV Equations Describing the Interaction of Equatorial and Midlatitude Rossby Waves 被引量:1
4
作者 Joseph A. BIELLO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2009年第5期483-504,共22页
Amplitude equations governing the nonlinear resonant interaction of equatorial baroclinic and barotropic Rossby waves were derived by Majda and Biello and used as a model for long range interactions (teleconnections... Amplitude equations governing the nonlinear resonant interaction of equatorial baroclinic and barotropic Rossby waves were derived by Majda and Biello and used as a model for long range interactions (teleconnections) between the tropical and midlatitude troposphere. An overview of that derivation is nonlinear wave theory, but not in atmospheric presented and geared to readers versed in sciences. In the course of the derivation, two other sets of asymptotic equations are presented: the long equatorial wave equations and the weakly nonlinear, long equatorial wave equations. A linear transformation recasts the amplitude equations as nonlinear and linearly coupled KdV equations governing the amplitude of two types of modes, each of which consists of a coupled tropical/midlatitude flow. In the limit of Rossby waves with equal dispersion, the transformed amplitude equations become two KdV equations coupled only through nonlinear fluxes. Four numerical integrations are presented which show (i) the interaction of two solitons, one from either mode, (ii) and (iii) the interaction of a soliton in the presence of different mean wind shears, and (iv) the interaction of two solitons mediated by the presence of a mean wind shear. 展开更多
关键词 Coupled KdV equations Equatorial Rossby waves Solitary waves Atmospheric teleconnections
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部