测控装备机内测试设备计量校准技术研究

研究测控装备机内测试设备计量校准方法，获取机内测试设备技术状态的准确信息，是确保测控装备量值准确可靠的基础。以系统理论为指导，研究测控装备机内测试设备的工作运行机理和计量校准方法，选取某型测控装备，分析其技术要求、确定校准点、校准接口和校准设备，明确计量校准项目和参数，对提出的测控装备机内测试设备计量校准方法进行实验验证，为今后开展机内测试设备计量校准提供了方法和依据。     

Assessing ecohydrological factors variations and their relationships at different spatio-temporal scales in semiarid area,northwestern China

As a typical semiarid farming-pastoral ecotone sensitive to the environmennt, the Plain of West Liaohe Basin (WLBP) is currently experiencing drastic environmental changes. To identify how environmental change affect vegetation in the WLBP, we analysed spatiotemporal variation characteristics of Ecological environment factors based on monthly and annual air temperature (T), precipitation (P) and Normalized Difference Vegetation Index (NDVI) from 1982 to 2015. And the correlations between them were investigated by correlation analysis (Simple correlation, partial correlation and complex correlation) at temporal and spatial scale. The results showed that: (1) the vegetation growth of the WLBP showed ameliorated trend, with a change rate of 0.004/yr.; (2) P was more sensitive to NDVI than T; (3) and the influence of hydrothermal changes on vegetation growth was more significant than that of the change of single climate factors at time scales; (4) the effects of anthropogenic factors on vegetation change were 75.07% (1982–1993) and 98.08% (1994–2015), respectively. At the temp-special scales, P&T and land use type change (LUCC) were the main climatic and anthropogenic factors that affect vegetation changes, respectively.     

单通道控制旋转弹系统动力学建模与Hopf分岔

为准确预测旋转弹系统的锥形运动形态并判断其稳定性，提出一对鸭舵引起的气动不对称性以及可能引起复杂非线性动力学特性的非线性因素，建立能准确描述单通道控制旋转弹系统姿态运动的复数形式的动力学模型并分析讨论其动态稳定性条件。利用分岔理论对单通道控制旋转弹系统开展Hopf分岔研究，给出了Hopf分岔发生的判断准则；推导了用于判定极限环稳定的第一Lyapunov系数。数值仿真结果验证了条件的正确性与有效性并发现了拟周期运动及混沌运动。研究结果为旋转弹的控制参数设计及结构参数设计提供理论参考。     

Brief Introduction about the SVOM Mission

SVOM is a mission dedicated for studying γ-Ray Bursts, and will also be a powerful target-ofopportunity observatory for the whole astronomy community. The mission has been approved jointly by both Chinese and French space agencies. It is planned to be in the orbit in 2021 with an altitude ≤ 600 km and an inclination ≤ 30°.      

衣服铺陈的岁月

有着特殊含义的衣服．只生存在某个特定年代的人群的集体记忆中．当记忆的阀门偶然打开．过去的时光就这样带着厚重的灰尘在一件件衣服上铺陈开来。     

STRAIN MEASUREMENT IN THE SMART COMPOSITE

ＳＴＲＡＩＮＭＥＡＳＵＲＥＭＥＮＴＩＮＴＨＥＳＭＡＲＴＣＯＭＰＯＳＩＴＥＬｉａｎｇＤａｋａｉ；ＴａｏＢａｏｑｉ（ＳｅｎｓｏｒｉｎｇａｎｄＴｅｓｔｉｎｇＲｅｓｅａｒｃｈｉｎｓｔｉｔｕｔｅ，ＮａｍｉｎｇＵｎｉｖｅｒｓｉｔｙｏｆＡｅｒｏｎａｕｔｉｃｓａｎｄ...     

智能化传感器综述

本文简要介绍了智能化传感器的基本概念及国内外发展动向.在介绍智能化传感器的类型及主要组成部分的基础上,还以实例说明智能化传感器在航空、航天技术、工业控制、机器人等方面的应用.最后对智能化传感器的优缺点进行了分析,展望了智能化传感器在我国的发展.     

双损耗Al2O3基多孔吸波材料的制备及其吸波性能

基于片状Al₂O₃陶瓷互锁结构强度高的特点,制备出夹杂石墨的高气孔率的Al₂O₃多孔陶瓷,并通过原位还原在多孔骨架中制备出Ni微粒,形成一种轻质的双损耗陶瓷基吸波材料。通过XRD、FE-SEM和EDS研究了还原温度对多孔吸波材料的组成、微观形貌、元素分布和吸波性能的影响。结果表明,还原温度升温至700 ℃可将多孔网络中Ni完全还原,形成以堆叠互锁Al₂O₃为基,夹杂片状石墨和孔表面覆盖Ni微粒的双损耗轻质吸波材料。当复合材料厚度为6.5 mm时,最小反射损耗为-35.01 dB,有效吸收带宽达到1.75 GHz。片状Al₂O₃锁定的石墨片构筑的导电网络,Ni微粒与基体之间的极化效应等共同促进复合材料良好的微波吸收性能。     

关键参数对二冲程煤油发动机爆震的影响

针对二冲程汽油发动机改用航空煤油后的爆震抑制和性能恢复进行了研究,利用GT-Power软件建立发动机的一维仿真模型并对煤油发动机的爆震进行了预测和优化。仿真结果表明:推迟点火时刻、远低于和远大于理论空燃比的混合气对爆震都有一定的抑制作用,试验结果验证了仿真结果的正确性。提出并采用协同推迟点火和增加喷油的控制策略进行试验研究。试验结果表明:在低转速大负荷工况下,爆震可被有效抑制,节气门全开时功率恢复在90%以上。发动机转速为5 500 r/min时,功率恢复能达到原机的95.7%。