一类Koblitz椭圆曲线的快速点乘

考虑一类特征3的Koblitz椭圆曲线的快速点乘算法.在这类曲线上适合建立低带宽的、可证明安全的密码体制.结果显示,利用这类曲线的复乘性质,使用模约减和Frobenius展开技巧,这类曲线上存在一种不带预计算的快速点乘算法,其运算速度是通常的重复加倍-点加算法的6倍.该算法的快速优化原理与有限域算术优化和椭圆曲线点的坐标表示的选取无关.

在Qt上实现蒙文显示的设计与实现

随着软件产业国际化进程的发展,在操作系统中实现对我国少数民族文字的显示是一项具有挑战性和刻不容缓的任务,针对这项任务先分析了少数民族文字中蒙古文的语法特点和书写特点、桌面系统平台库QT的体系结构特点以及OpenType字体文件的特点,在此基础之上提出在QT中使用OpenType字体文件来实现蒙古文显示的详细实现方案,最后给出了目前该方案在项目中的实现情况和效果,并阐述了还有哪些地方需要进一步研究和改进。

PHOTOVOLTAIC EFFECT AND ITS POLARITY IN SI DOPING SUPERLATTICES

We have studied the photovoltaic effects in Si doping superlattices (nipi) under different excitation conditions with and without additional cw optical biasing using a He-Ne laser. On the basis of the photovoltaic theory of carrier spatial separation in superlattices, we propose the concept of spatial fixity of the photovoltage polarity in type-II superlattices and examine the experimental results. The photovoltaic effect in Si nipi is found mainly from the direct transitions related with shallow impurities in real space, not the electron-hole band-to-band process as in GaAs nipi.

Ordering along <111> and <100> directions in GaInP demonstrated by photoluminescence under hydrostatic pressure

Photoluminescence of GaInP epilayers under hydrostatic pressure is investigated. The Gamma valley of disordered GaInP shifts sublinearly upwards with respect to the top of the valence band with increasing pressure and this sublinearity is caused by the nonlinear dependence of lattice constant on the hydrostatic pressure. The Gamma valleys of ordered GaInP epilayers rise slower than that of the disordered one. Considering the interactions between the Gamma valley and folded L and X valleys, the pressure dependence of the band gap of ordered GaInP is calculated and fitted. The results demonstrate that not only ordering along [111] directions but also sometimes simultaneous ordering along [111] and [100] directions can occur in ordered GaInP. (C) 1996 American Institute of Physics.

非掺杂LEC砷化镓晶体中砷沉淀和位错关联性质

通过使用激光散射扫描的方法,定性地研究非掺杂半绝缘LEC砷化镓（100）方向生产的晶体中砷沉淀在晶体径向截面分布,得到了在一种特定热场中生长的晶体中存在4个砷沉淀的聚集中心结论,而这4个聚集中心却正好是晶体上位错密度相对较低的区域.作者主要研究了这种分布和位错之间的关系,分析其形成过程,并得出在晶体生长及后期退火过程中,位错在晶体中起到了输送砷原子的管道作用,加速了砷原子在晶体中的扩散过程,导致网格位错密集区的大直径砷沉淀的密度相对位错稀疏区和位错线区的砷沉淀密度较低.

A New Method to Investigate InGaAsP Single-Photon Avalanche Diodes Using a Digital Sampling Oscilloscope

A near-infrared single-photon detection system is established by using pigtailed InGaAs/InP avalanche photodiodes. With a 50GHz digital sampling oscilloscope, the function and process of gated-mode (Geiger-mode) single-photon detection are intuitionally demonstrated for the first time. The performance of the detector as a gated-mode single-photon counter at wavelengths of 1310 and 1550nm is investigated. At the operation temperature of 203K,a quantum efficiency of 52% with a dark count probability per gate of 2. 4 * 10~(-3), and a gate pulse repetition rate of 50kHz are obtained at 1550nm. The corresponding parameters are 43% , 8. 5 * 10~(-3), and 200kHz at 238K.

扩展OSL方法校准微波双口测试夹具

常规的OSL（open-short-load）校准方法具有简便易行的特点，被广泛应用于单端口测量的测试夹具的校准。在本文中，OSL方法被首次扩展应用于双端口夹具的校准，并消除该方法带来的相位不确定问题。通过实验证明这种方法与SOLT（short-open-load-thru）方法同样精确。

日本、华北落叶松幼——成龄相关选择模型及早期选择

为了加速日本、华北落叶松的遗传改良进程，缩短育种周期，本文建立了用于早期选择的年遗传增益最大模型 (MAGG) 和最大未来净值模型 (MFNW)。遗传力平方根比率(g)、幼-成龄遗传相关系统(r) 和遗传预测系数等参数可用8种随时间函数来逼近，根据残差平方和与非线性回归相关指数，以二次抛物线式拟合的精度最高。不同模型利用的评价标准及参数逼近的函数不同，估算的最佳选择年龄 (tmax) 也不同。对于 MFNW模型，tmax的确定受生物学因子和经济学因子的共同影响。估算的结果表明，日本、华北落叶松的早期选择都是有效的。如果轮伐期（T）为20年，考虑改良的性状为材积，对于日本落叶松可用早期的树高作为选择指标，初选在2龄进行，第二次选择在7－8龄，早期选择的相对效率 (RSE) 分别为 14.2037 和 2.5017－1.9378；对于华北落叶松，当用树高作为早期选择指标时，第一次选择在3龄 (RSE=3.1711)，第二次选择在 9－10 (RSE=1.5492－1.4561)，当用树高年生长最作为早期选择指标时，第一次选择在4龄 (RSE=1.1276)，第二次选择在 7－8 (RSE=1.3343－1.3436)。本文对不同轮伐期的tmax和其他性状的早期选择也作了探讨。