立足高端 自主创新——沈阳机床在航空制造业的发展之路

沈阳机床以紧密联合具有传统学科优势的高校院所为基础、以主动贴近用户深入了解用户工艺需求为途径、以积极承担国家各级政府重大科技项目为载体,着重开展面向航空领域的研究与工作。     

Flight Record of the Long March Series of Launch Vehicles

(Continued)THE 62ND LAUNCH On September 1,2000, a LM-4B launch vehicle lifted off with ZY-2 (01 resources satellite from Taiyuan Satellite Launch     

论中华民族凝聚力的产生

本文在理解中华民族内涵的基础上,探讨了中华民族形成的重要阶段,阐释了中华民族凝聚力的重要标志,重点论述了中华民族凝聚力产生的早期特征。从而论证了中华民族不可分割的文化根源。     

Executive Moves of CASC

On April 15,2013,the central committee of CPC and the State Council of China decided to establish a Board of Executives for China Aerospace Science and Technology(CASC)and Mr.Xu Dazhe was appointed Chairman of CASC     

一种快速的飞行器布局方案优选方法

本文引用系统模糊优选理论与基于数理统计正交表的设计法相结合来处理飞行器布局方案优选问题，并举例说明具体用法，文中方法对整个飞行器方案选择有一定参考价值。     

Solar activity prediction studies and services in NAOC

Solar activity prediction services started in 1960’s in National Astronomical Observatories, Chinese Academy of Sciences (NAOC). As one of the members of the International Space Environment Service (ISES), Regional Warning Center of China (RWC-China) was set up in 1990’s. Solar Activity Prediction Center (SAPC), as one of the four sub-centers of RWC-China, is located in NAOC. Solar activity prediction studies and services in NAOC cover short-term, medium-term, and long-term forecast of solar activities. Nowadays, certain prediction models, such as solar X-ray flare model, solar proton event model, solar 10 cm radio flux model, have been established for the practical prediction services. Recently, more and more physical analyses are introduced in the studies of solar activity prediction, such as the magnetic properties of solar active regions and magnetic structure of solar atmosphere. Besides traditional statistics algorithms, Machine Learning and Artificial Intelligence techniques, such as Support Vector Machine (SVM) method, are employed in the establishment of forecast models. A Web-based integrated platform for solar activity data sharing and forecast distribution is under construction.     

Passive target tracking using maximum likelihood estimation

Estimation of target trajectory from passive sonar bearings and frequency measurements in the presence of multivariate normally distributed noise, with unknown inhomogeneous general covariance, is modeled as a nonlinear multiresponse parameter estimation problem. It is shown that maximum likelihood estimation in this case is identical to optimizing a determinant criterion which has a concise form and contains no elements of unknown covariance matrix. A Gauss-Newton type algorithm using only the first-order derivatives of the model function and a new convergence criterion, is presented to implement such estimation. The simulation results demonstrate that performance of the maximum likelihood estimation method with the above noise model is superior to that with the traditional noise assumption     

箭遥时间指令参数实时处理方法研究

火箭遥测数据的实时挑点处理结果是发射中心实时监视火箭飞行状态的重要依据,尤其是时间指令参数的处理结果为判别运载火箭发动机点火、关机、星箭分离等关键事件发生与否提供主要依据。根据某型号运载火箭时间指令参数在遥测帧格式中的波道和码位分配,分析目前箭遥时间指令实时处理方法存在的缺陷,提出"增加判别帧数,充分利用冗余信息",通过分析"时序指令"与"时串指令"间存在的"关联"建立"关联知识库",使用知识库进行辅助判别,实现不错判、不漏判的改进设想。     

三角带失效概率模型

通过失效物理分析，考虑了挠性传动件-三角带的受力和变形．剖析了其失效形式．根据其特殊的失效物理背景推导了数学模型，提出宜采用最弱环模型，大样本试验证实了上述分析。     

模具约束条件对H96黄铜双脊矩形管E弯截面变形的影响

 双脊矩形管的绕弯成形受内外侧模具的共同约束,不同模具约束下管坯的受力不同,使得其截面变形情况也不相同,而截面变形严重地影响弯管件的成形质量和使用性能。因此,基于ABAQUS有限元平台建立了双脊矩形管E弯成形三维有限元模型,并通过实验验证了模型的可靠性。采用所建模型,研究了内外侧模具约束条件对双脊矩形管E弯截面变形的影响规律,发现当只有内腹板脊槽受约束时,内腹板脊槽的内缩变形可得到较好的控制,而其他部位的变形则有增大的趋势;当只有外腹板脊槽受约束时,内腹板脊槽宽度变形基本不发生变化,而其他部位的变形则有减小的趋势;当内外腹板脊槽均受约束时,可较好地控制双脊矩形管E弯过程中的截面变形。芯头个数对整管截面高度、宽度、外腹板脊槽宽度与两脊槽底部的间距的变形影响较大,但对内腹板脊槽宽度的变形影响不显著。