奥氏体不锈钢温加工新技术的研究

奥氏体不锈钢 1Cr18NigTi 的温加工温度范围以 200—400℃为宜。在此温度范围内加工时,钢具有较低的变形抗力、较高的工艺塑性,加工后具有良好的力学性能。当变形速率一定时,真应力的大小取决于变形温度和变形程度。当 T=200—400℃ 时,σ=Kε~n;当 T=400—600℃ 时,σ=K_1ε~ne~(B/T_K)。钢的变形抗力、塑性和加工后室温力学性能的变化主要是由钢组织中的双晶界间距和位错密度的变化所决定。     

高斯和估计Kalman滤波在多平台空战对抗评估数据预处理中的应用

针对多平台空战对抗评估数据预处理中的过程积累误差问题进行研究。通过构建多平台空战对抗系统,分析不同平台间实时数据交互关系和相应的数据类型,采用最小二乘法和坐标变换实现不同平台间的时空配准,并对多平台空战对抗评估过程进行误差分析,将其状态误差和观测误差表示为高斯和形式,并选用Kalman滤波方法对过程积累误差进行滤波。实例仿真实验结果表明:经过滤波后的估计轨迹与真实轨迹之间的拟合效果较好,进一步完善了原有多平台空战对抗数据预处理过程。     

化学改性聚丙烯腈原丝热应力的研究

采用对比的方法,研究了在热氧稳定化过程中,经高锰酸钾（ＫＭｎＯ４）改性的纤维与未改性纤维的热应力变化。实验表明,两咎纤维在稳定化过程听热应力变化可分为物理和化学变化两个阶段。在相同热氧稳定化条件下,要使两种纤维在物理变化范围内得到相同内和,改性纤维所需负荷较小;在化学变化区,改性纤维所对应的热应力峰值温度较低,表明改性对热氧稳定化反应具有一定的催化作用。     

基于进化神经网络的入侵检测方法

将神经网络与遗传算法结合,提出入侵检测的进化神经网络方法,它是个高效并行非线性动态处理系统,可以满足实时处理要求·首先用遗传算法优化神经网络结构,然后用优化的神经网络进行入侵检测预测、预警·用进化神经网络方法不断演化,寻找最优的网络结构·当进化神经网络学会系统正常工作模式后,能够对偏离系统正常工作的事件做出反应,进而可以发现一些新的攻击模式·实验表明预警率是很高的     

无粘结预应力砼框架梁施工工艺的保证和改进措施

以贵阳龙洞堡机场航站楼等工程为例，讨论后张法无粘结钢绞线预应力砼框架梁施工中的钢绞线，钢丝束、锚夹具等材质检验，以及准确控制张拉力，施工中伸长值，摩阻、变形等参数的定量监测。工程实践表明，自行组装的实验装置及专用机具使用方便可靠，施工中改进措施简便可行，各项指标符合（JGJ／T92－93）《无粘结预应力砼结构技术规程》及设计要求。     

The 1997-1998 warm event in the South China Sea

A strong warm event happens during spring 1997 to spring 1999 in the South China Sea. Its intensity and duration show that it is the strongest event on the record over the past decades. It also corresponds with the severe flood over the valley of the Yangtze River and a couple of marine environmental events. This note addressed the evolution process by using several data sets, such as sea surface temperature, height and wind stress in addition to subsurface temperature. The onset of the warm event almost teleconnects with the El Ni?o event in the tropical Pacific Ocean. Summer monsoon is stronger and winter monsoon is weaker in 1997 so that there are persistent westerly anomalies in the South China Sea. During the development phase, the warm advection caused by southerly anomalies is the major factor while the adjustment of the thermocline is not obvious. Subsequently, the southerly anomalies decay and even northerly anomalies appear in the summer of 1998 resulting from the weaker than normal summer monsoon in 1998 in the South China Sea. The thermocline develops deeper than normal, which causes the downwelling pattern and the start of the maintaining phase of the warm event. Temperature anomalies in the southern South China Sea begin to decay in the winter of 1998-1999 and this warm event ends in the May of 1999.     

师范院校高级英语教学策略分析

师范院校的高级英语课的教学,一直面临一个师生两难的教学状况.为提高教学质量,应更新教学理念,改进教学方法.同时,还要体现师范特色,增加职训力度.     

2002： The extra-strong warm winter event in North Asia and its accompanying anomalous atmospheric circulation

Features of an extra-strong warm winter event in North Asia in 2002 and its accompanying anomalous atmospheric circulation were studied through diagnosis on the atmospheric reanalysis data set. Results show that the winter of 2002 is of the warmest in the recent 54 years in North Asia, which was caused by both decadal scale and interannual scale variability. The interannual variability is proved to be as the main cause for the event, and it is related to the global scale atmospheric circulation anomalies, with the strongest of them in the Eastern Hemisphere and in the middle and high latitude region of the Southern Hemisphere.     

L波段数字微波本振源设计

叙述了集成锁相本振源的原理、关键技术及设计过程 ,并应用Motorola大规模集成电路 ,采用“脉冲吞食”可变分频技术设计L波段锁相本振源 ,达到了很好的指标     

基于小波变换的ECG信号消噪

以小波变换的多分辨率分析为理论基础 ,依据信噪在小波分析下的分离性 ,对体表心电信号 (ECG信号 )进行了消噪算法的设计与实现 ,并着重强调了其中双尺度预处理算法的重要性 .实验表明 ,本消噪算法不仅能实时有效地降噪 ,还能对原信号突变点进行定位