基于素数的混沌伪随机数发生器的安全性分析

分析了一类基于素数的混沌伪随机数发生器的安全性问题。分析表明,此类混沌伪随机数发生器的输出不是密码学安全的伪随机序列,在截获不长的一段序列的基础上即可很容易地恢复此类PRNGs的全部密鈅。虽然基于素数的方法在改善混沌序列相关性能、周期长度等方面具有一定的优势,但是却不能增加序列的不可预测性,这就限制了此类混沌伪随机数发生器在诸多应用领域中的应用前景。     

小型汽油发电机组智能式电子调速系统方案设计

汽油机调速性能是影响小型汽油发电机组电气性能指标的重要因素。目前,使用机械式转速调整装置的小型汽油机的转速调整率较大,从而严重影响了小型汽油发电机组电气性能。提出了基于PIC单片机智能式数字步进电机调速系统去解决小型汽油发电机组中汽油机转速稳定性问题,给出了调速系统详细硬件和软件设计方案。该方案经实际验证是可行的。     

Investigation on energy output structure of explosives near-ground explosion

In order to give the energy output structure of typical explosives near-ground explosion in real ground conditions, the free-field shockwave, ground reflection shockwave and Mach wave overpressure time history of composition B explosive, RDX explosive and aluminized explosive were measured by air pressure sensors and ground pressure sensors. The shape of the free-field shock wave, ground reflection shock wave, and Mach wave and explosion flame were captured by high-speed camera. The experimental results show that, at the same horizontal distance from the initiation point, the peak overpressure of explosive shock wave of composition B explosive, both in the air and on the ground, is less than that of RDX and aluminized explosives. At a distance of 3.0 m from the initiation point, the peak overpressure of aluminized explosives is slightly less than that of RDX explosives. Owing to the exothermic effect of aluminum powder, the pressure drop of aluminized explosives is slower than that of RDX explosives. At 5.0 m from the initiation point, the peak overpressure of aluminized explosives is larger than that of RDX explosives. At the same position from the initiation point, among the three kinds of explosives, the impulse of aluminized explosives is the maximum and the impulse of composition B explosives is the minimum. With the increase of the horizontal distance from the initiation point, the height of Mach triple-points (Mach steam) of the three explosives increases gradually. At the same horizontal distance from the initiation point, there is poorly difference in the height of Mach triple-points between aluminized explosive and RDX explosive, and the height of Mach triple-points of composition B explosive is much smaller than that of other two explosives. The maximum diameter and duration of the fireball formed by aluminized explosives are the largest, followed by composition B explosive, and the maximum diameter and duration of the fireball formed by RDX explosive are the smallest.     

基于GUI和矢量信号源的微波着陆信号模拟器设计

提出了基于GUI和矢量信号源的微波着陆信号模拟器设计方法。首先利用MATLAB图形用户界面开发环境设计了集信号参数设置、干扰模拟和基带数据生成于一体的基带波形仿真功能;其次提出了一种改进的扫描波束模拟方法,实现了对微波着陆扫描信号的精确模拟;最后利用矢量信号源MG3700A对基带数据进行混合调制。测试结果表明,该信号模拟器达到设计要求。     

平视显示器教学模拟器改进设计研究

用80C196单片机作为显示处理机构成一块基于AT总线的插卡,用以取代原平视显示器教学模拟器显控计算机和矢量产生器插件板,使系统结构简化、成本降低,并提高系统可靠性。部分设计实例已应用在某型飞机模型器火控系统部件、某型平视显示器电子部件改进设计中。     

舰船汽力装置变工况性能的图形化处理

应用现代计算机图形处理方法动态地描述舰用蒸汽动力装置及其设备的变工况性能数据,包括用图形交互的方式输入、显示和保存数据等关键内容．该方法已用于实际工程分析．     

舰船蒸汽动力装置热线图优化的程序设计与研究

介绍了用于舰船蒸汽动力装置热线图优化的可视化程序设计与研究.阐述了软件的主要功能、开发环境、数据库设计以及关键技术问题的解决途径.程序能通过调整各种设计参数来得到良好的热线图.