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91.
分辨率增强技术(RET)设计流程中聚集了各式各样的点工具和方法。当前对深亚波长可制造性(DFM)设计的要求迫使设计与制造行业必须建立十分密切的合作关系。同时也促使EDA行业提供一种平台,以促进这些行业间的密切交流。合理利用这一平台将会对产能和品质产生直接的影响。 相似文献
92.
Vortex pinning in type-II superconducting films can be effectively controlled by combining these films with different ferromagnetic
nanostructures. In this article an overview is presented of different types of ferromagnetic pinning centers. The investigated
hybrid structures consist of Pb films that are deposited on top of arrays of ferromagnetic dots with in-plane magnetization
(IMP) or out-of-plane magnetization (OPM), ferromagnetic films with IPM or OPM that contain arrays of submicron holes (antidots),
or continuous films with OPM and a magnetic domain structure. Interesting effects such as field-polarity dependent vortex
pinning and the dependence of the pinning strength on the domain structure of the ferromagnet are observed. Our experiments
demonstrate that vortex pinning in superconductors is strongly influenced by the magnetic properties of the different ferromagnetic
pinning centers. 相似文献
93.
This paper presents a method to measure the sensitivity of microwave components to memory effects caused by the dc biasing circuit. This allows us to determine the required (impedance) properties of the dc biasing circuit to reduce slow dynamics under a certain level. The proposed measurement technique is based on the nonlinear vectorial network analyzer, which allows us to measure not only the absolute magnitude but also the absolute phase relations between the waves. Superimposing a multisine excitation signal on the dc bias allows us to measure the slow dynamics caused by the dc biasing circuit as a function of frequency and input power. Furthermore, it is verified whether or not the measured phenomena depend on the type of excitation signal. 相似文献
94.
Varghese B Rajan V Van Leeuwen TG Steenbergen W 《The Review of scientific instruments》2007,78(12):126103
The performance of a graded index multimode fiber optic low coherence Mach-Zehnder interferometer with phase modulation is analyzed. Investigated aspects were its ability to measure path length distributions and to perform path length resolved Doppler measurements of multiple scattered photons in a turbid suspension of particles undergoing Brownian and translational motion. The path length resolution of this instrument is compared with a system using single mode fibers for illumination and detection. The optical path lengths are determined from the zero order moment of the phase modulation peak in the power spectrum. The weighted first moment, which is equal to the average Doppler shift, shows a linear response for different mean flow velocities within the physiological range. 相似文献
95.
An extension to model-based electron energy loss spectroscopy (EELS) quantification is reported to improve the possibility of modelling fine structure changes in electron energy loss spectra. An equalisation function is used in the energy loss near edge structure (ELNES) region to model the differences between a single atom differential cross section and the cross section for an atom in a crystal. The equalisation function can be shown to approximate the relative density of unoccupied states for the given excitation edge. On a set of 200 experimental h-BN spectra, this technique leads to statistically acceptable models resulting into unbiased estimates of relative concentrations and making the estimated precisions come very close to the Cramér-Rao lower bound (CRLB). The method greatly expands the useability of model-based EELS quantification to spectra with pronounced fine structure. Another benefit of this model is that one also gets an estimate of the unoccupied density of states for a given excitation edge, without having to do background removal and deconvolution, making the outcome intrinsically more reliable and less noisy. 相似文献
96.
Broersen B Van Krevelen F van Heusden JT van Heukelom JS 《The Review of scientific instruments》1979,50(7):897-899
A method is described for building a low-voltage-drift differential dc amplifier featuring automatic zero adjustment, a high input impedance, and a bandwidth of 10 kHz. This is achieved by an asymmetric two-step process between the input signal and ground. Bandwidth can be extended by the use of a second amplifier during the ground-sampling time. The amplifier can be made with standard electronic components. A major advantage of this method is that an existing amplifier can easily be converted into a low-voltage-drift amplifier by adding the essential elements of the described automatic zero-adjusting amplifier to its input stage. To illustrate the method a practical example is constructed featuring a drift of 0.2 microV/ degrees C. 相似文献
97.
98.
99.
G E Tanner D G Angers D M Van Ess C A Ward 《Computer methods and programs in biomedicine》1986,23(3):237-242
Simulations based on physiologic modeling have been used for over twenty years to clarify the pharmacokinetics of inhaled anesthetics. We describe ANSIM, an anesthesia simulator for the IBM PC. ANSIM uses established modeling techniques to create a life-like anesthesia simulator. ANSIM is useful as an educational tool for demonstrating classic concepts of uptake and distribution of inhaled anesthetics. 相似文献
100.
Structural serviceability problems such as excessive vibrations and deflections associated with human movements have recently become of great concern. The recommended design values for human loading in the current U.S. building codes and standards were developed over half a century ago and are based on strength requirements alone. Recent investigations have led to load models for individuals and small groups of people using laboratory measurements on small and medium size force platforms. The current project has been directed towards testing the group load model. We designed and built a floor system instrumented with strain gages and displacement transducers to measure dynamic loads due to large groups of people. We investigated the floor system experimentally and analytically. The input dynamic forces were determined using data from the displacement transducers and also from the strain gages. The measured results compared closely with the predicted group loads obtained from our computer simulation model developed previously. 相似文献