地球反照对数字太阳敏感器的影响分析

地球反照对太阳敏感器性能有重要影响,同时也制约着太阳敏感器在卫星上的安装。由于数字太敏感器本身独特的结构模型,所以需要采取有针对性的方法对其进行影响分析。本文在此模型基础上提出了利用图像技术的地球反照影响分析方法,为太阳敏感器在航天器上的应用与安装提供了技术支持。     

椭圆回路下暗条电流的特性

给出了椭圆暗条电流回路下暗条垂直平衡方程,并用它计算了NOAA131活动区暗条的平衡电流,分析了其暗条电流的特性.      

飞机座舱显示界面脑力负荷测量与评价

脑力负荷是影响飞行安全的重要因素之一,对飞行员脑力负荷进行客观测量,对于飞机座舱显示界面脑力任务的工效评价与优化设计具有重要意义.基于ERP（Eveat Related Potential）技术,选取失匹配负波（MMN,Mismatch Negativity）和P3a成分为指标,采用三刺激“oddball”模式,在飞行模拟任务条件下开展了三级脑力负荷的测量与评价研究.实验结果表明,MMN峰值和P3a峰值对脑力负荷变化敏感,随着脑力负荷的增加,MMN峰值显著增加,而P3a峰值显著降低,反应了被试者对异常信息的自动加工能力的提高以及朝向注意能力的减弱.与新异刺激相比,由偏差刺激所诱发的MMN与P3a成分对于与飞行任务相关的脑力负荷具有更好的敏感性,将可用于进一步的脑力负荷分级评价.      

低速风洞均匀吸气地板下阻塞对地板边界层影响的研究

为了研究低速风洞地板下部阻塞对地板上表面边界层的影响以及控制方法,在国防科技大学KD-03低速风洞利用均匀吸气地板系统进行了实验研究.地板下部阻塞对地板上表面主流区的流动产生干扰,并影响边界层的分布和发展,随着地板下部阻塞度的增加,地板上表面边界层的厚度有增加的趋势;在某一阻塞度和吸气系数下,来流速度越大,地板下部的阻塞对主流区流动的影响越小;地板的均匀吸气使边界层的厚度显著降低,也有效减小因地板下部阻塞引起的主流区流动的不均匀性.该实验的研究结论为8m×6m风洞均匀吸气地板系统研制提供了参考.     

内圣外王

内圣是人格主体在德、能、学三个基本方面的自我修养,其至高境界是"极高明而道中庸";外王则是指卓越的"治平"社会功德.内圣是外王的前提和基础,外王是内圣的实践归宿和社会价值体现.内圣外王具有道德的、政治的和学术的三重理想人格涵义.内圣外王人格论的思想理论基础是传统的民本思想、"人贵论"和"人性论".     

剪切流场中液滴形变的三维力学模型初探

分析了油水乳化液中分散相液滴的受力及形变,从理论上提出了剪切流场中液滴形变的三维力学模型.通过实验观测了液滴在由两个同心圆筒形成的旋转剪切流场中的变形情况,并对建立的三维力学模型进行了验证.测量结果表明:实验观测值和理论值有较好的一致性.未加乳化剂时,在z方向上,随着液滴拉伸率的增加,液滴的变形收缩系数也随之增加;与未加乳化剂时相比,加入乳化剂时液滴的变形收缩系数偏离理论值更大;对于有表面活性剂的自由液滴来说,液滴破裂所需要的临界剪切率比没有表面活性剂时要低.     

Profile error compensation in precision grinding of ellipsoid optical surface

Optical glass elements with the ellipsoidal surface are used in many critical aerospace instruments, such as satellites, telescope and cameras. Their optical performance is mainly affected by profile accuracy and surface quality. In this paper, a rectangular ellipsoid surface is precisely ground on a BK7 optical glass blank by grating scanning grinding path with a three-axis CNC precision surface grinder. A profile error compensation procedure for ellipsoidal grinding is proposed based on the error analysis about the primary error sources in the XY and YZ projection planes during the grinding process. The mathematical prediction models of the wheel arc profile error, the measurement and wear error of the grinding wheel radiuses are established. By applying the proposed error compensation procedure, the profile accuracy of the ellipsoidal surface was improved from 4 μm to 2 μm in the XY plane, and improved from 15 μm to 5 μm in the YZ plane.     

Radio emission from coronal streamers

Different models of coronal streamers are used to calculate the radio brightness temperature at the wavelengths of observation of the Nançays Radioheliograph. Calculation are performed assuming the location of the streamer both on the disk and at the limb. Their comparison with observations show that a satisfactory agreement with a particular model can be found in the shape and in the relative enhacement of the streamer with respect to the quiet Sun, although the absolute values of the computed brightness temperatures are much higher than the observed ones.     

Magnetic fine structures in coronal loops

The formation of magnetic fine structures and associated electric currents is considered in the context of the coronal heating problem. The penetration of field-aligned electric currents into the lower atmosphere is discussed. It is argued that currents strong enough to heat the corona can persist only for short periods of time. The formation of thin current sheets is discussed. It is argued that photospheric magnetic structures (flux tubes) play an important role in the generation of coronal currents.     

亚声速圆柱绕流的摄动Galerkin杂交解

本文采用摄动伽辽金杂交方法，应用计算机代数与符号运算求解亚声速圆柱绕流。对给定的马赫数，获得了速度势的近似解表达式，并与Ｊａｎｚｅｎ－Ｒａｙｌｅ－ｉｇｈ方法进行了对比。计算结果表明本方法精度高，计算工作量小，解的表达式简洁。