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991.
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Wang K. Bryant C. Carlson M. Elmer T. Harris A. Garcia M. Hui C.S. Leong C.K. Reynolds B. Tang R. Weber L. Wenzel J. Wilson G. Becker M. 《Micro, IEEE》1995,15(2):44-49
The MPC105 peripheral component interconnection bridge/memory controller provides a platform-specification-compliant bridge between Power PC microprocessors and the PCI bus. With it, designers can create systems using peripherals already designed for a variety of standard PC interfaces. This bridge chip also integrates a secondary cache controller and high-performance memory controller that supports DRAM or synchronous DRAM and ROM or flash ROM 相似文献
994.
The Sabra salt-sensitive SBH/y and salt-resistant SBN/y rats constitute a unique experimental model of hypertension in which salt-susceptibility is genetically determined and expressed only after salt-loading, without the development of spontaneous hypertension. To determine the genetic basis of salt-susceptibility in the Sabra rats, the candidate gene and total genome screen approaches were adopted. The likely candidate genes in this model incorporate salt-related physiological mechanisms such as the nitric oxide system, the arginine vasopressin axis and the epithelial sodium channel. In the random genome search scheme for culprit genes, SBH/y and SBN/y were cross-bred. A highly unusual and composite mode of transmission of salt-susceptibility was found in this cross, emphasizing the complexity of the genetic basis of salt-susceptibility. Linkage analysis of the entire rat genome with a large number of widely distributed microsatellite markers identified three putative gene loci on chromosomes 1 and 17 that contribute importantly to salt-sensitivity and/or resistance, and uncovered sex specificity in the role that salt-susceptibility genes fulfill in the development of hypertension. 相似文献
995.
Application of the Taguchi Method to the Optimization of the Submerged Arc Welding Process 总被引:2,自引:0,他引:2
Application of the Taguchi method to the optimization of the submerged arc welding process is reported. The Taguchi method is used to formulate the experimental layout, to analyze the effect of each welding parameter on welding performance, and to predict the optimal setting for each welding parameter. Experimental results are provided to confirm the effectiveness of this approach. 相似文献
996.
Minimally perturbing, resistive, nonferrous probes were developed for noninvasively measuring hazardous currents induced in the human body by electromagnetic fields at 1-200 MHz. Each probe has a resistive toroidal coil that is placed around the leg or other body member. An electrostatic shield is required to limit capacitive coupling. A new shielded test fixture provides TEM fields for calibration with a voltage standing wave ratio (VSWR) less than 1.1 from 1 to 200 MHz. A man-sized phantom was exposed to the near field of a vertical monopole antenna at 29.9 MHz, and the value of the current measured in the leg with the probe is in reasonable agreement with measured heating. Analyses and experiments show that commercial ferrous current probes modify the circuit in which they are used, changing the current being measured. Less change is caused by the authors' nonferrous current probes 相似文献
997.
Shealy J.B. Hashemi M.M. Kiziloglu K. DenBaars S.P. Mishra U.K. Liu T.K. Brown J.J. Lui M. 《Electron Device Letters, IEEE》1993,14(12):545-547
A technology for increasing both the two-terminal gate-drain breakdown and subsequently the three-terminal-off-state breakdown of AlInAs/GaInAs high-electron-mobility transistors (HEMTs) to record values without substantial impact on other parameters is presented. The breakdown in these structures is dependent on the multiplication of electrons injected from the source (channel current) and the gate (gate leakage) into the channel. In addition, holes are generated by high fields at the drain and are injected back into the gate and source electrodes. These phenomena can be suppressed by increasing the gate barrier height and alleviating the fields at the drain. Both have been achieved by incorporating a p+-2DEG junction as the gate that modulates the 2DEG gas and by utilizing selective regrowth of the source and drain regions by MOCVD. The 1-μm-gate-length devices fabricated have two-terminal gate-drain and three-terminal-off-state breakdown voltages of 31 V and 28 V, respectively 相似文献
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1000.
The effects of nitric oxide (NO) annealing on conventional thermal oxides are reported in this letter. The oxide thickness increase, resulting from NO annealing, is found to be only a few angstroms (<0.5 nm) and independent on the initial oxide thickness. Furthermore, both the electrical and physical characteristics are improved. This technique is expected to achieve sub-5 nm high quality ultrathin dielectric films for the applications in EEPROM's and ULSI 相似文献