利用格壁安装角对栅格舵展开折叠压心控制的工程方法研究探索

随着技术的发展，在工程设计中，对于巡航迎角下栅格舵导弹的展开与折叠的压心变化控制对于控制系统来说尤为重要。本文创新性的首次提出利用栅格舵的内壁单元的偏转，即相对于水平面的夹角来实现在设计点下的压心控制。由于设计过程需要多次迭代，本文利用计算在所关注的设计点处对展开折叠压心进行了验证，创造性的利用了等效代替的方法提出了一种新型的计算折叠状态压心的快速工程方法。     

Single track and single layer formation in selective laser melting of niobium solid solution alloy

Selective laser melting (SLM) was employed to fabricate Nb-37Ti-13Cr-2Al-1Si (at%) alloy, using pre-alloyed powders prepared by plasma rotating electrode processing (PREP). A series of single tracks and single layers under different processing parameters was manufactured to evaluate the processing feasibility by SLM, including laser power, scanning speed, and hatch distance. Results showed that continuous single tracks could be fabricated using proper laser powers and scanning velocities. Both the width of a single track and its penetration depth into a substrate increased with an increase of the linear laser beam energy density (LED), i.e., an increase of the laser power and a decrease of the scanning speed. Nb, Ti, Si, Cr, and Al elements distributed heterogeneously over the melt pool in the form of swirl-like patterns. An excess of the hatch distance was not able to interconnect neighboring tracks. Under improper processing parameters, a balling phenomenon occurred, but could be eliminated with an increased LED. This work testified the SLM-processing feasibility of Nb-based alloy and promoted the application of SLM to the manufacture of niobium-based alloys.     

Noise analysis of continuous GPS coordinate time series for CMONOC

The Crustal Movement Observation Network of China (CMONOC) is one of the major scientific infrastructures, mainly using Global Positioning System (GPS) measurements, to monitor crustal deformation in the Chinese mainland. In this paper, decade-long coordinate time series of 26 continuous GPS sites of CMONOC are analyzed for their noise content using maximum likelihood estimation (MLE). We study the noise properties of continuous GPS time series of CMONOC for the unfiltered, filtered solutions and also the common mode signals in terms of power law plus white noise model. In the spatial filtering, we remove for every time series a common mode error that was estimated from a modified stacking of position residuals from other sites within ∼1000 km of the selected site. We find that the common mode signal in our network has a combination of spatially correlated flicker noise and a common white noise with large spatial extent. We demonstrate that for the unfiltered solutions of CMONOC continuous GPS sites the main colored noise is a flicker process, with a mean spectral index of ∼1. For the filtered solutions, the main colored noise is a general power law process, indicating that a major number of the filtered regional solutions have a combination of noise sources or local effects. The velocity uncertainties from CMONOC continuous GPS coordinate time series may be underestimated by factors of 8–16 if a pure white noise model is assumed. In addition, using a white plus flicker noise model, the median values of velocity errors for the unfiltered solutions are 0.16 (north), 0.17 (east) and 0.58 (vertical) mm/yr, and the median values for the filtered solutions are 0.09 (north), 0.10 (east) and 0.40 (vertical) mm/yr.     

复合材料缠绕气瓶可靠性验证技术

根据航天器用复合材料气瓶高可靠性特点,对复合材料气瓶的可靠性进行了分析,气瓶的失效模式主要为泄漏和爆破,影响因素分别为疲劳寿命和承压能力,其中疲劳寿命主要受内衬影响,而承压能力主要由复合层性能决定。最后对气瓶的可靠性试验进行了描述,举例说明了气瓶的可靠度试验验证方法。     

Lateral Flight Technical Error Estimation Model for Performance Based Navigation

Flight technical error (FTE) combined with navigation system error (NSE) is the main part of total system error (TSE) in performance based navigation (PBN).The implementation of PBN requires pre-flight prediction and en-route short-term dynamical prediction of the TSE.Once the sum of predicted lateral FTE and NSE is greater than the specified PBN value,the PBN cannot operate.Thus,accurate modeling and thorough analysis of lateral FTE are indispensible.Multiple-input multiple-output (MIMO) lateral track control system of a transport aircraft is designed using linear quadratic Gaussian and loop transfer recovery (LQG/LTR) method,and the lateral FTE of a turbulence disturbed approach operation is analyzed.The error estimation mapping function of latera FTE and its bound estimation algorithm are proposed based on singular value theory.According to the forming mechanism of lateral FTE,the algorithm considers environmental turbulence fluctuation disturbance,aircraft dynamics and control system parameters.Real-data-based Monte-Carlo simulation validates the theoretical analysis of FTE.It also shows that FTE is mainly caused by turbulence fluctuation disturbance when automatic flight control system (AFCS) is engaged and would increase with escalating environmental turbulence intensity.     

一种用于液晶曝光中的激光检测系统

介绍了一种非接触式激光检测系统，可用于检测液晶曝光中液晶模板与基板之间的间隙，给出了该种系统的测量原理、硬件系统、信号处理方法、测量结果、分辨力和误差分析，并指出了这种测量系统的应用。     

关于推动国内奖励旅游发展的若干思考

文章阐述了奖励旅游的概念及其规模大、消费高且稳定等特点,分析了奖励旅游对企业员工、出资企业以及旅行企业所产生的综合效应,最后结合奖励旅游市场目前所存在的市场培育及旅游产品设计的问题进行分析,并对旅游政策、经营观念的转变及产品的设计思路等方面提出了见解.     

建立中小企业诊断专家系统的构想

运用考试法、直接认定法、临时聘请法遴选专家，组建由政府、企业和民间协会共同组成的专家系统，对中小企业（宏观）发展与（微观）运行中的问题进行咨询和诊断，是我国中小企业快速、健康发展不可缺少的条件。作者对建立这一专家系统的有关问题，提出了自己的看法。     

两级运载火箭回收方案设想

文章通过对K—1运载火箭的回收方案进行分析研究,提出回收质量分别为10t和20t的两级运载火箭的回收方案设想。文章指出,根据现有的回收技术水平,对运载火箭的回收是完全可行的。     

管道振动问题中一种辛变换的计算方法

以符合哈密顿(Hamiltonian)特性的管道振动方程的简化问题给出了一种具体的计算方法.为了保持原方程哈密顿结构,这种简化过程中使用的矩阵必须是辛矩阵(sympletic matrix).针对管道振动方程给出一种辛矩阵的计算方法,该方法利用了哈密顿方程线性部分的特征空间,用特征空间的一些性质来完成辛矩阵的计算.