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101.
从理论上探讨了磁阻率效应,叙述了精密角位移传感器的工作原理及结构设计。传感器的分辨率已达0.01°,通过可靠性寿命试验,传感器的失效率λ(t)<1×10-7/h。  相似文献   
102.
本文利用选区电子衍射,并结合X射线衍射对六种不同成份的急冷合金及其退火后的相组成进行了鉴定,得到了它们的相组成。  相似文献   
103.
提出了红外加热胶接的思想,并对红外加热胶接技术作了简单阐述。介绍了一种红外加热胶接矿用阻燃、防腐、橡塑风筒布的装置。  相似文献   
104.
文章叙述了中央人民广播电台新业务楼空调工程中采用蓄冰空调制冷新技术的情况。文章讲解了蓄冰空调原理,并对蓄冰制冷与常规制冷技术进行比较,指出:从节电上来考虑,前者具有经济性。文章最后列举了今后在设计和维护上,还有待解决的一些问题。  相似文献   
105.
An athermal 40-channel dense wavelength-division-multiplexing multi/demultiplexer using a novel combination technology is proposed. It consists of one 1times4 100- to 400-GHz spacing interleaver filter and four sub-arrayed-waveguide gratings (AWGs). The temperature-dependent wavelength shift of the combined device is successfully suppressed to 0.058 nm in the -20degC to 70degC temperature range. Moreover, the combined device's adjacent crosstalk (typically -35 dB) is much better than conventional AWGs (typically -25 dB).  相似文献   
106.
A 4-MB L2 data cache was implemented for a 64-bit 1.6-GHz SPARC(r) RISC microprocessor. Static sense amplifiers were used in the SRAM arrays and for global data repeaters, resulting in robust and flexible timing operation. Elimination of the global clock grid over the SRAM array saves power, enabled by combining the clock information with array select signals. Redundancy was implemented flexibly, with shift circuits outside the main data array for area efficiency. The chip integrates 315 million transistors and uses an 8-metal-layer 90-nm CMOS process.  相似文献   
107.
A novel configuration of balanced frequency InGaAs pseudomorphic high electron mobility transistor (PHEMT) monolithic microwave integrated circuit (MMIC) tripler is proposed. A resonant LC filter is used to eliminate the fundamental frequency and a phase delay line is employed to suppress the second harmonic. The separation of the independent phase shifters makes the tripler more compact and flexible. The conversion loss of the tripler operating from 12 to 36GHz is less than 9.4dB at 9-dBm input power. As compared to the third-harmonic frequency, the fundamental frequency is suppressed more than 21.4dB while for the second harmonic is more than 22.3dB at 36GHz.  相似文献   
108.
A set of robust MPEG-2 video watermarking techniques is proposed, focusing on commonly used typical geometric processing for bit-rate reduction, cropping, removal of any rows, arbitrary-ratio downscaling, and frame dropping. Both the embedding and the extraction of watermarks are done in the compressed domain, so the computational cost is low. Moreover, the watermark extraction is blind, i.e., no original unwatermarked MPEG-2 video is needed for watermark extraction. The presented technique is applicable not only to MPEG-2 video, but also to other DCT-based coding videos. Selected experimental results validate our techniques.  相似文献   
109.
An analytical current-voltage (I-V) model for planar-doped HEMTs is developed. This compact model covers the complete range of I-V characteristics, including the current saturation region and parasitic conduction in the electron-supplying layer. Analytical expressions for the small-signal parameters and current-gain cutoff frequency are derived from the I-V model. Modeling results for a 0.1-μm-gate planar-doped AlInAs-GaInAs HEMT show excellent agreement with measured characteristics. Threshold voltages and parasitic conduction in planar-doped and uniformly doped HEMTs are also compared and discussed  相似文献   
110.
Multicasting in a class of multicast-capable WDM networks   总被引:1,自引:0,他引:1  
Multicast is the ability to transmit information from a single source node to multiple destination nodes. Multicast can be supported more efficiently in optical domain by utilizing the inherent light-splitting capacity of optical switches than by copying data in electronic domain. In this paper, we study multicast communication in a class of multicast-capable WDM networks (i.e., the networks that have light splitting switches) with regular topologies under some commonly used routing algorithms. Upper and lower bounds on the minimum number of wavelengths required are determined for a network to be rearrangeable for arbitrary multicast assignments, and compared with those WDM networks without light splitting switches. Our results indicate that in most of the networks we study, the number of wavelengths required can be significantly reduced by utilizing light splitting switches  相似文献   
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