A geometric proof of the definability of Hausdorff limits

We give a geometric proof of the following well-established theorem for o-minimal expansions of the real field: the Hausdorff limits of a compact, definable family of sets are definable. While previous proofs of this fact relied on the model-theoretic compactness theorem, our proof explicitly describes the family of all Hausdorff limits in terms of the original family.     

TMS320C64x系列DSP的UTOPIA接口设计与实现

ATM传输是宽带综合业务数字网的重要技术,为使DSP能接入ATM系统,利用TMS320C64x特有的UTOPIA接口构建了一个ATM系统的从设备.介绍了UTOPIA接口基本的发送和接收操作流程,设计了与主控制器MPC8260连接的接口电路,重点探讨了UTOPIA从设备端的参数设置要点,并给出部分程序段代码.     

基于PIC24FJ64GA002的车辆轴载质量静态称量系统设计

介绍了一种基于PIC24FJ64GA002和24位A/D转换器ADS1232的车辆轴载质量静态称量系统。该系统在车辆静态情况下称量其轴载质量、总质量。系统的工作原理为：A/D转换器ADS1232在PIC24FJ64GA002的控制下采集质量传感器输出的信号，并把转换后的数据传送到PIC24FJ64GA002进行相应的处理和存储：然后再把存储在PIC24FJ64GA002内部SRAM中的数据送到计算机进行显示、打印、存储等处理。系统可应用于大型地磅称量的场合，也可应用于高速公路收费站，用于检查过往的超载车辆。     

On lovely pairs of geometric structures

We study the theory of lovely pairs of geometric structures, in particular o-minimal structures. We use the pairs to isolate a class of geometric structures called weakly locally modular which generalizes the class of linear structures in the settings of SU-rank one theories and o-minimal theories. For o-minimal theories, we use the Peterzil-Starchenko trichotomy theorem to characterize for a sufficiently general point, the local geometry around it in terms of the thorn U-rank of its type inside a lovely pair.     

High-pressure high-temperature behavior of nitrogen-doped zirconia

The stability of nitrogen-doped zirconia/zirconium oxonitride Zr₇O₁₁N₂ has been studied at pressures up to 20 GPa and temperatures up to 2273 K using a multi-anvil press and X-ray powder diffraction. Depending on pressure and temperature it was found to decompose into the respective stable oxides and nitrides. Therefore the critical influence of temperature, pressure and consequently mechanical tension on doped materials have been revealed. The transition pressures of some oxidic and nitridic high-pressure modifications have been confirmed. The coefficient of thermal expansion of Zr₇O₁₁N₂ was determined to α(T)=17.94(20)×10⁻⁶ K⁻¹+6.35(14)×10⁻⁹ K⁻²×T.     

基于TMS320C64XX和有限状态机的高速多通道RS译码器设计

RS码是一种纠错能力很强的码,广泛应用于通信、数字存储等领域中.文中提出了一种新的基于有限状态机结构的高速多通道RS译码器的设计方法,并且在TMS320C64XX系列DSP上对其进行了优化设计.测试结果表明采用采用该方法设计的RS译码器可以在单片DSP中实现高速多通道实时系统的需求.     

Internet上电子邮件的安全机制

近年来，Internet用户已不满足于简单电子邮件．要求提供多用途的和安全的电子邮件，为此出现了MIME，PEM，PGP和MOSS，S/MIME，PGP／MIMF，MIMEWithMSP等多种方案、本文综述了这些方案，尤其对安全机制进行了详细的讨论。     

Irreducible representations of the quantum analogue of SU(2)

We give the complete set of irreducible representations of U(SU(2))_q when q is a mth root of unity. In particular, we show that their dimensions are less or equal to m. Some of them are not highest-weight representations.     

Equilibrium phase behavior of aqueous two-phase systems containing 17R4/L64 and citrates

The cloud points (CPs) of the copolymers 17R4 and L64 were first measured, and then the effects of salts ((NH₄)₃C₆H₅O₇, K₃C₆H₅O₇) on 17R4 and L64 were researched. After finishing the work described above, the temperature (278.15, 283.15, and 288.15) K of aqueous two-phase systems was determined, which consist of 17R4-(NH₄)₃C₆H₅O₇, 17R4-K₃C₆H₅O₇, L64-(NH₄)₃C₆H₅O₇, and L64-K₃C₆H₅O₇. Finally, the liquid–liquid equilibrium (LLE) data of binodal curve and the tie line for 17R4-(NH₄)₃C₆H₅O₇ aqueous two- phase systems (ATPSs) 17R4-K₃C₆H₅O₇ ATPSs, L64-(NH₄)₃C₆H₅O₇ ATPSs, and L64-K₃C₆H₅O₇ ATPSs were obtained. Nonlinear fitting of the empirical equation was used for making the diagram. The results showed that the change in the size of the two-phase areas increases with the increase of temperature. The capacity of the salts to induce phase segregation follows the Hofmeister series, that is, K₃C₆H₅O₇?>?(NH₄)₃C₆H₅O₇. In addition, the findings also showed that the phase separation ability of 17R4 is better than that of L64.