预处理实时数字仿真方法

本文对半实物数字仿真的数学模型提出了一种预处理实时数字仿真方法。在保持原模型精度的基础上,该方法将在每帧内的数字仿真时间由作四次右函数计算的时间减少到作一次计算的时间。本文阐明了推导这种方法的思路、步骤,给出了误差估计并指出了这种方法计算的复杂性。     

撩起"人性自私论"的面纱

随着我国社会改革的深入,"人性论"之争再次成为理论界关注的热点,这一争论,实质上是关系"举什么旗,走什么路"的问题.由于争论双方对"自私"含义的不同理解,往往使得争论成了两股道上跑的车.因此,撩起"人性自私论"的面纱,科学界定并明晰"自私"内涵,不仅是理论界统一思想,科学认识"人性"的前提,而且也是引导社会形成正确的价值理念,自觉抵制"人性自私论"侵蚀的重要保证.     

数控车床长度补偿功能的使用研究

数控车床上坐标指令（G92、G54～G59）与刀具长度补偿功能（Txxyy,调用xx号刀具和yy号刀补）不能同时使用,当调用后者时,前者指定的工件原点自动失去作用,与数控铣床上两者的使用方法不同.数控车床的对刀方法有其特殊性.本文介绍数控车床上对刀操作,长度补偿值的设置方法,说明长度补偿与编程坐标系原点的关系,长度补偿功能的使用技巧.     

质子交换膜燃料电池及其空间应用

介绍了质子交换膜燃料电池(PEMFC)、可再生燃料电池(RFC)的工作原理、性能和空间应用特点，以及发展航空航天器用可再生PEMFC系统的必要性和可行性。讨论了PEMFC和可再生PEMFC系统所面临的技术难点。最后，针对我国的实际情况，提出了分阶段发展PEMFC和可再生PEMFC的建议。     

准分子激光矫正屈光不正的原理及其实现

研究了准分子激光治疗屈光不正的原理及其实现方法，介绍了准分子激光治疗屈光不正的原理及其种类。在初始角膜模型假设的基础上，提出了能够用于近视、远视和散光等屈光手术的数学模型，计算出切削量和切削的层数，并给出了相应的算法框图。就准分子激光角膜切削机理和“飞点扫描”等关键技术进行了研究。研究成果直接用于准分子激光眼科治疗机，并给出了准分子激光眼科治疗机的原理框图。实验和临床数据表明。取得了满意的手术效果。     

Factors influencing the heating of the auroral electrojet by high power radio waves

Results are presented from recent ionospheric modification experiments in which the EISCAT UHF radar measured the E-region temperature and density response to high power RF heating above Tromsø. A variety of electrojet conditions were encountered during these experiments. In particular, the electron drift velocity varied considerably allowing the heating efficiency of the RF heater to be investigated as a function of electron flow velocity. These observations constitute the first direct investigation of electrojet temperature modifications by high power radio waves and provide a test of a recent theoretical model in which the combined effects of RF heating and of natural plasma turbulence associated with the Farley-Buneman instability have been considered.     

Autonomous navigation using the TDRSS Onboard Navigation System (TONS)

The National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) is currently developing a Tracking and Data Relay Satellite (TDRS) System (TDRSS) Onboard Navigation System (TONS) to provide onboard knowledge of highly accurate navigation products autonomously to users of TDRSS. The TONS I operational system processes Doppler data derived from scheduled forward-link S-band services to provide onboard orbit and frequency determination and time maintenance. TONS I is implemented using a stable onboard frequency reference, a Doppler measurement capability in the user transponder, and onboard navigation/signal acquisition software. The success of the TONS experiment (1992/1993), which was implemented on the Explorer Platform/Extreme Ultraviolet Explorer (EP/EUVE) spacecraft, demonstrated the flight readiness of TONS I. TONS II-A provides the user with additional Doppler data derived from an S-band beacon signal, available approximately 80 percent of the time. This paper describes the TONS operational capabilities, configurations, and expected performance.     

基于三因素模型的企业持续经营高风险预测研究

随着竞争的日趋激烈，企业持续经营不确定性显著增加，尽旱识别企业持续经营面临的风险，对于企业管理者、投资者来说都具有重要意义。现有的持续经营高风险研究依然没有摆脱“资料驱动型”的困境，文章根据三因素模型建立持续经营高风险预测模型。     

测微目镜-TV测读系统在测量金属线胀系数中的应用

鉴于光杠杆法测量金属线膨胀系数的缺点,依据金属线膨胀系数测量原理,采用测微目镜-TV测读系统测量金属线膨胀系数,并做了可行性分析,在此基础上,设计出了一整套完整的测量金属线膨胀系数的方法,进行了大量的实验,取得了较多的实验数据,并进行了数据分析,最后认为运用测微目镜-TV测读系统测量金属线胀系数,提高了被测物体微小位移的可视度,大大降低了系统误差.