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61.
M. Trunk J. Popp I. Hartmann M. Lankers E. Urlaub W. Kiefer 《Fresenius' Journal of Analytical Chemistry》1996,355(3-4):354-356
In situ measurements of gas-liquid surface reactions of single aerosol microdroplets are presented. By means of optical levitation in combination with elastic (Mie) and inelastic (Raman) light scattering it is possible to get information on the chemistry of e.g. acid/base reactions as well as the physical behavior of single microparticles. 相似文献
62.
Arafa M. Fay P. Ismail K. Chu J.O. Meyerson B.S. Adesida I. 《Electron Device Letters, IEEE》1996,17(3):124-126
We report on the fabrication and characterization of high-speed p-type modulation-doped field-effect transistors (MODFETs) with 0.7-μm and 1-μm gate-lengths having unity current-gain cut-off frequencies (fT) of 9.5 GHz and 5.3 GHz, respectively. The devices were fabricated on a high hole mobility SiGe heterostructure grown by ultra-high-vacuum chemical vapor deposition (UHV-CVD). The dc maximum extrinsic transconductance (gm) is 105 mS/mm (205 mS/mm) at room temperature (77 K) for the 0.7-μm gate length devices. The fabricated devices show good pinch-off characteristics and have a very low gate leakage current of a few μA/mm at room temperature and a few nA/mm at 77 K 相似文献
63.
Li Z.-M. Landheer D. Veilleux M. Conn D.R. Surridge R. Xu J.M. McDonald R.I. 《Photonics Technology Letters, IEEE》1992,4(5):473-476
The authors have developed a 2-D device simulator for heterostructure metal-semiconductor-metal (MSM) photodetectors. They have incorporated a model of multilayer optics into the simulator and used it to analyze the temporal response of a resonant-cavity enhanced heterostructure with a confining buffer layer and a distributed Bragg reflector (DBR). The authors show that through fine tuning the layer thicknesses, optical resonance enhancement of the light absorption can be obtained 相似文献
64.
65.
I. Havezov 《Fresenius' Journal of Analytical Chemistry》1996,355(5-6):452-456
AAS as a highly sensitive and specific single element technique is ideally suited as a detector for speciation analysis. The combinations of chromatographic separation with element specific detectors (flame AAS, electrothermal AAS (ETAAS), hydride generation AAS (HGAAS)) provide powerful approaches to the determination of all species. Sample stabilisation is the area that requires most attention as it still represents the main source of problems encountered in speciation work. The correct speciation depends on how the sample is handled prior to analysis. Unfortunately, no universal procedure has been found. Anything that changes redox conditions, pH or complexation equilibrium is clearly unacceptable. 相似文献
66.
Dynamic Programming (DP) applies to many signal and image processing applications including boundary following, the Viterbi algorithm, dynamic time warping, etc. This paper presents an array processor implementation of generic dynamic programming. Our architecture is a SIMD array attached to a host computer. The processing element of the architecture is based on an ASIC design opting for maximum speed-up. By adopting a torus interconnection network, a dual buffer structure, and a multilevel pipeline, the performance of the DP chip is expected to reach the order of several GOPS. The paper discusses both the dedicated hardware design and the data flow control of the DP chip and the total array.This work was supported in part by the NATO, Scientific and Environmental Affairs Division, Collaborative Research Grant SA.5-2-05(CRG.960201)424/96/JARC-501. 相似文献
67.
V. V. Veremey A. A. Kostenko I. K. Kuz'michev A. E. Poyedinchuk G. I. Khlopov 《Journal of Infrared, Millimeter and Terahertz Waves》1994,15(7):1283-1295
Reported here are the results on level and structure of the radiated field of an open resonator at and off resonance. On the basis of the modelling problem rigorous solution and the measurements at 4-millimeter wavelength we find there are no ways to compensate the radiated field from an open electromagnetic structure at resonance. Analysis of open resonator excitation efficiency shows that the mismatch loss of a slot-fed open resonator runs to 34% while at the aperture-feed excitation this is not more than 6% for the same-geometry resonator. 相似文献
68.
Obridko I. Ginosar R. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2006,14(9):1043-1047
In battery-operated portable or implantable digital devices, where battery life needs to be maximized, it is necessary to minimize not only power consumption but also energy dissipation. Typical energy optimization measures include voltage reduction and operating at the slowest possible speed. We employ additional methods, including hybrid asynchronous dynamic design to enable operating over a wide range of battery voltage, aggregating large combinational logic blocks, and transistor sizing and reordering. We demonstrate the methods on simple adders, and discuss extension to other circuits. Three novel adders are proposed and analyzed: a 2-bit pass transistor logic (PTL) adder and two dynamic 2-bit adders. Circuit simulations on a 0.18-mum process at low voltage show that leakage energy is below 1%. The proposed adders achieve up to 40% energy savings relative to previously published results, while also operating faster 相似文献
69.
QUALITATIVE AND QUANTITATIVE ANALYSIS OF STOCHASTIC PROCESSES BASED ON MEASURED DATA, II: APPLICATIONS TO EXPERIMENTAL DATA 总被引:1,自引:0,他引:1
Analysis of stochastic processes governed by the Langevin equation is discussed. The analysis is based on a general method for non-parametric estimation of deterministic and random terms of the Langevin equation directly from given data. Separate estimation of the terms corresponds to the decomposition of process dynamics into deterministic and random components. Part I of the paper presented several possibilities for qualitative and quantitative analysis of process dynamics based on such decomposition. In Part II, some of these analysis possibilities are applied to experimental datasets from metal cutting and laser-beam welding. 相似文献
70.
A. I. Makarov 《Journal of Applied Mechanics and Technical Physics》2002,43(5):694-700
Aeroacoustic resonant oscillations (aeolian tones) are studied for flow past two plates forming a cross in a square cross section channel. Possible oscillation modes are classified on the basis of admissible symmetry groups and the existence of the modes is proved. The infinite linear system of equations for these modes obtained by the sewing method was simplified and studied numerically. Curves of eigenfrequency versus plate length are constructed. The form of the eigenfunctions is studied. 相似文献