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排序方式: 共有1734条查询结果,搜索用时 46 毫秒
921.
Hamzaoglu F. Zhang K. Yih Wang Ahn H.J. Bhattacharya U. Zhanping Chen Yong-Gee Ng Pavlov A. Smits K. Bohr M. 《Solid-State Circuits, IEEE Journal of》2009,44(1):148-154
A high-performance low-power 153 Mb SRAM is developed in 45 nm high-k Metal Gate technology. Dynamic SRAM PMOS forward-body-bias (FBB) and Active-Controlled SRAM VCC in Sleep are integrated in the design to lower Active-VCCmin and Standby Leakage, respectively. FBB improves the Active-VCCmin by up to 75 mV, and Active-Controlled SRAM VCC distribution tightened by 100 mV, both of which result in further power reduction. A 0.346 mum2 6T-SRAM bit-cell is used which is optimized for VCCmin, performance, leakage and area. The design operates at high-speed over a wide voltage range, and has a maximum frequency of 3.8 GHz at 1.1 V. The 16 KB Subarray was also used as the building block in on-die 6 MB Cache for Intel Core 2 Duo CPU in 45 nm technology. 相似文献
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Jaroszynski DA Bingham R Brunetti E Ersfeld B Gallacher J van der Geer B Issac R Jamison SP Jones D de Loos M Lyachev A Pavlov V Reitsma A Saveliev Y Vieux G Wiggins SM 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2006,364(1840):689-710
Plasma waves excited by intense laser beams can be harnessed to produce femtosecond duration bunches of electrons with relativistic energies. The very large electrostatic forces of plasma density wakes trailing behind an intense laser pulse provide field potentials capable of accelerating charged particles to high energies over very short distances, as high as 1GeV in a few millimetres. The short length scale of plasma waves provides a means of developing very compact high-energy accelerators, which could form the basis of compact next-generation light sources with unique properties. Tuneable X-ray radiation and particle pulses with durations of the order of or less than 5fs should be possible and would be useful for probing matter on unprecedented time and spatial scales. If developed to fruition this revolutionary technology could reduce the size and cost of light sources by three orders of magnitude and, therefore, provide powerful new tools to a large scientific community. We will discuss how a laser-driven plasma wakefield accelerator can be used to produce radiation with unique characteristics over a very large spectral range. 相似文献
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JW Durkee PP Antich EN Tsyganov A Constantinescu JL Fernando PV Kulkarni BJ Smith GM Arbique MA Lewis T Nguyen A Raheja G Thambi RW Parkey 《Canadian Metallurgical Quarterly》1998,43(10):2949-2974
An electronic collimation technique is developed which utilizes the chi-square goodness-of-fit measure to filter scattered gammas incident upon a medical imaging detector. In this data mining technique, Compton kinematic expressions are used as the chi-square fitting templates for measured energy-deposition data involving multiple-interaction scatter sequences. Fit optimization is conducted using the Davidon variable metric minimization algorithm to simultaneously determine the best-fit gamma scatter angles and their associated uncertainties, with the uncertainty associated with the first scatter angle corresponding to the angular resolution precision for the source. The methodology requires no knowledge of materials and geometry. This pattern recognition application enhances the ability to select those gammas that will provide the best resolution for input to reconstruction software. Illustrative computational results are presented for a conceptual truncated-ellipsoid polystyrene position-sensitive fibre head-detector Monte Carlo model using a triple Compton scatter gamma sequence assessment for a 99mTc point source. A filtration rate of 94.3% is obtained, resulting in an estimated sensitivity approximately three orders of magnitude greater than a high-resolution mechanically collimated device. The technique improves the nominal single-scatter angular resolution by up to approximately 24 per cent as compared with the conventional analytic electronic collimation measure. 相似文献
930.
VP Pavlov 《Canadian Metallurgical Quarterly》1998,(12):47-49
The paper gives the results of conservative and surgical rehabilitation of patients over 38 years after the foundation of an orthopedic service at the Institute of Rheumatology. Conservative treatments for rheumatic diseases (RD) such as position treatment, formation of a correct stereotype, treatment of the cervical portion of the spine in rheumatic arthritis (RA) and osteoarthrosis derformans (OAD) are evaluated. The author's own experience involving over 5000 operations on the locomotor apparatus in RD, which permits assessment of the most common and successful operations, such as sinovectomy, arthroplasty, arthrodesis, endoprosthesis. Rheumoorthopedics is a part of complex rehabilitative treatment for RD as it enables one to infer actively at different stages of RD and to achieve high results in patients, including those who unresponsive to medical treatment. 相似文献