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991.
通过对国有化工流通企业现状的分析。了解其在计划经济与市场经济中的不同表现,并试图找到阻碍其生存与发展的症结所在,提出国有化工企业生存与发展的对策。 相似文献
992.
Herein, we report an efficient process for preparing monodisperse Au@SiO2 nanoparticles using homogeneous shaking and without the use of surface‐coupling silane agents or large stabilizers. The resulting pure‐silica surface of the Au@SiO2 nanoparticles is very important for straightforward surface functionalization with different functional groups via well‐established silica surface chemistry. Subsequent covalent bioconjugation of the aldehyde‐functionalized Au@SiO2 nanoparticles with various biomolecules is successfully employed to make robust nanoprobes for fast, colorimetric DNA and protein detection based on the sequence‐specific hybridization properties of DNA and the specific binding affinity between proteins, respectively. 相似文献
993.
The Testbed for Distributed Processing, or Ted, consists of Intel Corp.'s iSBC 8086 single board computers (SBCs) organized into groups or clusters. Each cluster consists of several SBCs that communicate via a shared memory. Intercluster communication occurs through an Ethernet interface. A hardware monitor designed and implemented to handle the monitoring activities within a cluster in the Ted system is described. By using specified patterns and don't-care masks, the system can detect accesses to selected data, addresses, or blocks of addresses. This function helps monitor events such as the access or usage of a memory location or a group of mailbox addresses. It also determines the amount of time consumed by the performance of specific operations 相似文献
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997.
本文借助图论的理论,通过识别回路和不包含回路的由起始状态到终止状态的路径的方法,提出一种构造给定有穷自动机对应的正则表达式的新算法,并给出具体实例。 相似文献
998.
Kovsh D.I. Li Liu Bakhshi B. Pilipetskii A.N. Golovchenko E.A. Bergano N.S. 《IEEE journal of selected topics in quantum electronics》2002,8(3):597-602
Nonlinear interaction between signal channels may result in significant performance degradation in transoceanic dense wavelength-division-multiplexing (WDM) transmission systems operated at high bit rates. In this paper, we report that the nonlinear crosstalk for systems with high spectral efficiency can be suppressed if WDM channels are launched with orthogonal relative states of polarization. It is shown that for adjacent channels (that experience the strongest nonlinear interaction) the launched relative state of polarization is maintained over the large distance of low polarization-mode dispersion fiber typically used in undersea systems. Numerical studies, as well as experimental results, are presented for standard and dispersion slope-matched dispersion maps 相似文献
999.
Shen-Iuan Liu Dong-Shiuh Wu 《IEEE transactions on instrumentation and measurement》1995,44(4):915-917
A new universal biquadratic filter configuration using two current feedback amplifiers (CFA's) is presented. The proposed configuration can realize the second-order lowpass, bandpass, highpass, notch and allpass filters. Both the active and passive sensitivities are no more than unity. The natural frequency ω0 can be controlled by a grounded capacitor. The quality factor Q can also be independently controlled by a resistor. Moreover, the quality factor will be insensitive to the current tracking errors and output voltage tracking errors of the CFA's. Experimental results that confirm the theoretical analysis are obtained. The results are useful in analog filtering applications 相似文献
1000.