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91.
SrMgxTi1 - xO3 nanocrystals (x = 0.1–0.6) were synthesized by the stearic acid gel method. Powder samples were characterized by X-ray diffraction and X-ray photoelectron (XP) spectroscopy. The results showed that the lattice parameter a and the O 1s XP spectrum changed not only with the Mg content x but also with the grain size d of the samples. The conductivity of a thick film specimen fabricated on an aluminium oxide wafer was investigated in a nitrogen—oxygen atmosphere.  相似文献   
92.
93.
本文对弧型小方坯连铸机工艺与设备进行了分析,介绍了连铸生产的PLC控制系统。及其软件设计。  相似文献   
94.
本文介绍了用饱和蒸汽对冷凝式汽轮机进行清洗除垢时主要参数的确定、操作要点及清洗方案,清洗后的汽轮机运行正常。  相似文献   
95.
Novel algorithmic features of multimedia applications and advances in VLSI technologies are driving forces behind the new multimedia signal processors. We propose an architecture platform which could provide high performance and flexibility, and would require less external I/O and memory access. It is comprised of array processors to be used as the hardware accelerator and RISC cores to be used as the basis of the programmable processor. It is a hierarchical and scalable architecture style which facilitates the hardware-software codesign of multimedia signal processing circuits and systems. While some control-intensive functions can be implemented using programmable CPUs, other computation-intensive functions can rely on hardware accelerators.To compile multimedia algorithms, we also present an operation placement and scheduling scheme suitable for the proposed architectural platform. Our scheme addresses data reusability and exploits local communication in order to avoid the memory/communication bandwidth bottleneck, which leads to faster program execution. Our method shows a promising performance: a linear speed-up of 16 times can be achieved for the block-matching motion estimation algorithm and the true motion tracking algorithm, which have formed many multimedia applications (e.g., MPEG-2 and MPEG-4).  相似文献   
96.
97.
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 8, pp. 9–11, August, 1993.  相似文献   
98.
The adoption of asymmetrical digital subscriber lines (ADSL) technology in conjunction with the broadcast digital subscriber lines (BDSL) proposed in this paper could provide a cost effective solution for the introduction of digital video services in the near term. BDSL provides the same digital broadcast video programs to all subscribers through existing twisted pair telephone loops. In this paper, the basics of telephone loop-based digital subscriber lines are first discussed. Then the potential of BDSL is explored in the twisted pair loop plant near end crosstalk (NEXT), far end crosstalk (FEXT), and white noise environment. The capability of BDSL is examined with different serving areas and transmit power levels. The possibility of using orthogonal quadrature amplitude modulation (QAM) to implement a zero guard-band BDSL system is studied. Computer BDSL performance simulations are then presented. The combination of high-bit-rate digital subscriber lines (HDSL), ADSL, and BDSL can provide telephone subscribers many digital broadband services  相似文献   
99.
We report a detailed mapping of a 2-D dopant profile on a fully processed industrial sample with large dynamic range and high spatial resolution by utilizing a dopant-selective etching process and Atomic Force Microscopy. The experimental results show excellent agreement with those obtained from SRP and SIMS as corroborative methods. We also discuss the most critical factors which influence the applicability, reproducibility, and reliability of this method  相似文献   
100.
The effects of the plasma etching process induced gate oxide damages on device's low frequency noise behavior are investigated on MOSFET's fabricated with different field plate perimeter to gate area ratio antennas. Abnormal 1/f noise spectrum with a shoulder centered in the frequency range of 100 and to 1 kHz was frequently observed in small geometry devices, and it is attributable to a nonuniform distribution of oxide traps induced by plasma etching process  相似文献   
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