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1.
Advances in our basic scientific understanding at the molecular and atomic level place us on the verge of engineering designer structures with key features at the single nanometer scale. This offers us the opportunity to design computing systems at what may be the ultimate limits on device size. At this scale, we are faced with new challenges and a new cost structure which motivates different computing architectures than we found efficient and appropriate in conventional very large scale integration (VLSI). We sketch a basic architecture for nanoscale electronics based on carbon nanotubes, silicon nanowires, and nano-scale FETs. This architecture can provide universal logic functionality with all logic and signal restoration operating at the nanoscale. The key properties of this architecture are its minimalism, defect tolerance, and compatibility with emerging bottom-up nanoscale fabrication techniques. The architecture further supports micro-to-nanoscale interfacing for communication with conventional integrated circuits and bootstrap loading.  相似文献   

2.
Multireader multicase (MRMC) variance analysis has become widely utilized to analyze observer studies for which the summary measure is the area under the receiver operating characteristic (ROC) curve. We extend MRMC variance analysis to binary data and also to generic study designs in which every reader may not interpret every case. A subset of the fundamental moments central to MRMC variance analysis of the area under the ROC curve (AUC) is found to be required. Through multiple simulation configurations, we compare our unbiased variance estimates to na?ve estimates across a range of study designs, average percent correct, and numbers of readers and cases.  相似文献   

3.
Abstract

Two kinds of binary optical elements used in multi-channel one-dimensional Fourier spectrum analysis are introduced. One is equivalent to two overlapped line-type zone plates that are in two different orientations, and the other is composed of a line-type zone plate and a circular zone plate. In the output plane, the designed elements can simultaneously perform one-dimensional imaging of the input object in one direction and one-dimensional Fourier transformation in the perpendicular direction, respectively. Consequently, a series of one-dimensional spectra along different sectional lines of the object can be produced in the output plane. The elements are fabricated using the binary optical technique. Experiments show that these binary optical elements work well and are suitable for lensless optical processing systems.  相似文献   

4.
5.
Thermal decomposition in three binary monomer mixture systems containing an experimentally synthesized monomer (EXP3) and a commercial polyfunctional urethane monomer (U–4TXA) was examined in terms of differential thermal analysis (DTA) and simultaneous thermogravimetry (TG) analysis when a sample was heated to 800°C. The binary EXP3/U–4TXA monomer mixtures were visible light-cured (VLC) resins which included CQ (camphorquinone=0.5 wt%) and DMAEMA (dimethylaminoethyl methacrylate=0.5 wt%) as the photoinitiator. Their DTA curves showed that thermal decomposition initiated at around 300°C and finished at around 500°C. TG curves showed complete weight loss at 800°C during thermally induced decomposition: the decomposition reaction at weight losses of 5 to 50% was calculated from the slope of the (1/T) versus log10(Hr) diagram, because the exothermic decomposition temperature shown on DTA curves increased with increasing heating rate from 2 to 20°C/min. Thermal decomposition analysis showed that a decomposition with weight change had exothermic heats ranging from 0.38 to 1.07 kJ/g for the EXP U1 mixture, 1.06 to 1.76 kJ/g for EXP U2 and 1.74 to 2.02 kJ/g for EXP U3. Activation energy ranged from 1.42 to 1.89 kJ/mol at weight losses of 5 to 50% in the three binary EXP3/U–4TXA monomer mixture systems.  相似文献   

6.
A minisonicator to rapidly disrupt bacterial spores for DNA analysis.   总被引:9,自引:0,他引:9  
Concerns about the use of anthrax spores as a weapon of mass destruction have motivated the development of portable instruments capable of detecting and monitoring a suspected release of the agent. Optimal detection of bacterial spores by PCR requires that the spores be disrupted to make the endogenous DNA available for amplification. The entire process of spore lysis, PCR, and detection can take several hours using conventional methods and instruments. In this report, a minisonicator and prototype spore lysis cartridge were built to disrupt Bacillus spores in 30 s for rapid, real-time PCR analysis. Utilization of the minisonicator improved PCR analysis by decreasing the limit of detection, reducing the time of detection, and increasing the signal amplitude. Total time of spore disruption and detection using the minisonicator and a microchip PCR instrument was less than 15 min.  相似文献   

7.
This communication demonstrates the feasibility of the gel-clot method for the analysis of bacterial endotoxins in water extracts of perfluorocarbon which is a water insoluble liquid medical device. Perfluorocarbon (10 mL) was shaken with 10 mL water for 15 min at 2000 r/min and the endotoxin present was extracted to the aqueous phase without interference inhibition/enhancement of the product and the recovery of endotoxin added to perfluorocarbon was determined, A validation study confirmed that endotoxins presented in perfluorocarbon pass over into the aqueous phase at concentrations of 20, 10 and 5EU/mL with recoveries from 86.8% to 96.8%. Therefore, the gel-clot test is suitable for detecting bacterial endotoxins in perfluorocarbon which is a water insoluble medical device.  相似文献   

8.
The use of binary decision diagrams (BDDs) in fault tree analysis provides both an accurate and efficient means of analysing a system. There is a problem, however, with the conversion process of the fault tree to the BDD. The variable ordering scheme chosen for the construction of the BDD has a crucial effect on its resulting size and previous research has failed to identify any scheme that is capable of producing BDDs for all fault trees. This paper proposes an analysis strategy aimed at increasing the likelihood of obtaining a BDD for any given fault tree, by ensuring the associated calculations are as efficient as possible. The method implements simplification techniques, which are applied to the fault tree to obtain a set of ‘minimal’ subtrees, equivalent to the original fault tree structure. BDDs are constructed for each, using ordering schemes most suited to their particular characteristics. Quantitative analysis is performed simultaneously on the set of BDDs to obtain the top event probability, the system unconditional failure intensity and the criticality of the basic events.  相似文献   

9.
Matalgah MM  Knopp J  Eifler L 《Applied optics》1998,37(35):8233-8246
An analytic solution for real optimal filters is known, and the special case of optimal binary phase-only filters can be solved by a fast binning algorithm but no analytic solution is known. We establish a geometric solution for the design of optimal binary amplitude filters (OBAF's) and optimal binary phase-only filters (OBPOF's) for any object. The optimal filter is found in terms of maximizing the field strength at the origin in the correlation plane. We found that it is possible to construct a unique convex polygon by using an ordered set of phasors from the filter object's Fourier transform. This process leads eventually to an exact solution for the filter-design problem. We show that the maximum distance across the polygon divides the phasors into two groups: For the OBAF, it determines the group that is passed or blocked; for the OBPOF, it determines which group is passed with a zero or a pi phase shift. The shape of the convex polygon gives qualitative information on the criticalness and the tightness needed in the design process. It provides good insight into the binning-process algorithm and permits us to bound the error in the binning process. Design examples through computer simulation and applications in fingerprint identification are presented.  相似文献   

10.
The performance of the ordered-statistic greatest of (OSGO) constant false alarm rate (CFAR) scheme with binary integration for M non-coherent sweeps in Weibull background was investigated for homogeneous and non-homogeneous backgrounds, with an assumption of known shape parameter. This kind of processing is based on the fact that the clutter can be segmented in regions in many real radar scenarios where a timevarying two-parameter distribution function family can be fitted, but the clutter power may vary locally inside the region. Under the assumption of known shape parameter, the authors examined the changes of the false alarm rate and detection probability of the OSGO-CFAR with binary integration when the shape parameter differs from the nominal one, and compared them to those of the OSGO-CFAR with single pulse processing. The authors have derived analytic expressions of the detection probability and false alarm rate during clutter power transitions for the OSGO-CFAR with binary integration in Weibull background. It is shown that the OSGO-CFAR with binary integration can not only improve the detection performance significantly, but it also control the rise of the false alarm rate at clutter edges more effectively compared to the OSGO-CFAR with single pulse processing. Moreover, it exhibits a good immunity to the variation of the shape parameter.  相似文献   

11.
《Advanced Powder Technology》2021,32(10):3869-3884
The current numerical paper introduces the flow and heat transfer characteristics across a new configuration channel, namely: the curved-corrugated channel, using binary hybrid nanofluid. E-shaped baffles with different geometrical parameters have been employed while CuO / MgO-water nanofluid is experimentally prepared with different volume fractions 0.0–5%. Measured thermophysical properties is utilized to simulate the flow and heat transfer characteristics by adopting the κ-ε model. The influences of corrugations, baffles, and geometric parameters; gap ratio (GR = 0.2,0.3,0.4, and 0.5), blockage ratio (BR = 0.2,0.25,0.3, and 0.35), and pitch angle (β = 10°, 12.5°, and 15°) at different Reynolds number (8000–28000) are evaluated using thermal–hydraulic performance method. The outcomes show that vortex flow and increased turbulence will increase heat transfer due to influences of corrugations and baffles. It is confirmed that the flow variations governed by the geometric parameters of the design and the best performance produce at lowest pitch angle 10°, lowest gap ratio (GR = 0.2) and highest blocking ratio (BR = 0.35). Regards the fluid medium, CuO / MgO particles improve the thermophysical properties of the base fluid and thereby boost the thermal performance of the system. It has found new correlations between the Nusselt number, friction Factor and design parameters of tested channel with using binary hybrid nanofluid.  相似文献   

12.
In this communication we introduce the augmented-space recursion method coupled with the orbital peeling technique, as a powerful tool for the calculation of effective cluster interactions, useful for the study of alloy phase stability. An application to the well studied PdV system has been carried out. This work was done in collaboration with Tanusri Saha and Indra Dasgupta, S N Bose National Centre for Basic Sciences, Calcutta  相似文献   

13.
We developed and validated a new paper-based assay for the detection of human blood type. Our method involves spotting a 3 μL blood sample on a paper surface where grouping antibodies have already been introduced. A thin film chromatograph tank was used to chromatographically elute the blood spot with 0.9% NaCl buffer for 10 min by capillary absorption. Agglutinated red blood cells (RBCs) were fixed on the paper substrate, resulting in a high optical density of the spot, with no visual trace in the buffer wicking path. Conversely, nonagglutinated RBCs could easily be eluted by the buffer and had low optical density of the spot and clearly visible trace of RBCs in the buffer wicking path. Different paper substrates had comparable ability to fix agglutinated blood, while a more porous substrate like Kleenex paper had enhanced ability to elute nonagglutinated blood. Using optimized conditions, a rapid assay for detection of blood groups was developed by spotting blood to antibodies absorbed to paper and eluted with 200 μL of 0.9% NaCl buffer directly by pipetting. RBCs fixation on paper accurately detected blood groups (ABO and RhD) using ascending buffer for 10 min or using a rapid elution step in 100/100 blood samples including 4 weak AB and 4 weak RhD samples. The assay has excellent reproducibility where the same blood group was obtained in 26 samples assessed in 2 different days. Agglutinated blood fixation on porous paper substrate provides a new, simple, and sensitive assay for rapid detection of blood group for point-of-care applications.  相似文献   

14.
15.
《成像科学杂志》2013,61(5):408-418
Abstract

This paper proposes an objective distortion measure for binary images. Whereas most previously proposed measures decide the distortion weight of a distorted pixel based on the relationship with the neighbouring pixels in the spatial domain, we observe the characteristics of distorted pixels in multi-spectral spatial-frequency bands. Similarities between the binary wavelet transform and the human visual system are utilised to obtain the distortion weight. When we decide the distortion weight of a distorted pixel, we consider flatness, edge orientation and texture complexity of the distorted pixel at each level of binary wavelet decomposition. Experimental results on various sample images show that the proposed measure is more adequate to human than previously proposed measures.  相似文献   

16.
We demonstrate a novel array-based diagnostic platform comprising lipid/polydiacetylene (PDA) vesicles embedded within a transparent silica-gel matrix. The diagnostic scheme is based upon the unique chromatic properties of PDA, which undergoes blue-red transformations induced by interactions with amphiphilic or membrane-active analytes. We show that constructing a gel matrix array hosting PDA vesicles with different lipid compositions and applying to blood plasma obtained from healthy individuals and from patients suffering from disease, respectively, allow distinguishing among the disease conditions through application of a simple machine-learning algorithm, using the colorimetric response of the lipid/PDA/gel matrix as the input. Importantly, the new colorimetric diagnostic approach does not require a priori knowledge on the exact metabolite compositions of the blood plasma, since the concept relies only on identifying statistically significant changes in overall disease-induced chromatic response. The chromatic lipid/PDA/gel array-based "fingerprinting" concept is generic, easy to apply, and could be implemented for varied diagnostic and screening applications.  相似文献   

17.
A diffusionlike equation is derived within the coherent potential approximation (CPA) for type II (or inhomogeneous), superconducting binary alloys. Diagrammatic formulation of the CPA is employed to extend the derivations of Eilenberger and Usadel to nondilute random substitutional alloys A 1?s B s having arbitrary concentrations and scattering strength. The generalized diffusion coefficient satisfies a simple algebraic equation, the coefficients of which are connected to measurable physical quantities. The diffusionlike equation is valid for arbitrary values of the order parameter at arbitrary temperatures belowT c . When the order parameter Δ is small, simple expansions in terms of Δ would lead immediately to the generalized Landau-Ginzburg equations. The upper critical magnetic field and magnetization are expressed as functions of concentrations of the binary alloy.  相似文献   

18.
Spores from a variety of Bacillus species were analyzed with direct probe mass spectrometry using an electron monochromator to select electrons of distinct energies for ionization. Electron energies were chosen to match the electron capture energies of taxonomically important compounds such as dipicolinic acid and fatty acids. Previous negative ion interferences were not observed when the monochromator was used, and the signal-to-noise ratio of targeted compounds was significantly enhanced using this approach. To demonstrate the selectivity of the technique, the monochromator was swept over a range of electron energies while monitoring the masses of compounds with known electron capture energies. Scanning the monochromator while the mass spectrometer was operated in single-ion mode enabled dipicolinic acid to be detected in 10(5) spores. The results presented here demonstrate the utility of the electron monochromator for selectively ionizing compounds directly in bacteria and bacterial spores.  相似文献   

19.
Accurate assessment of liberation state of ore sample is important in mineral processing. In practice, the ore sample is mounted in resin, sectioned, and polished before its liberation state is measured by sectional analysis. This approach typically overestimates the degree of liberation in two-dimensional (2D) measurements. Several models have been proposed to overcome this stereological bias and correct this error in well-examined samples. However, their versatility remains poorly understood. Herein, a stereological correction method was developed for the liberation distribution. First, the complexity of particle sectional texture was assessed using the fractal dimension of the image intensity. Next, the magnitude of stereological bias and 2D measureable parameters such as fractal dimension was correlated by an all-encompassing simulation of various texture types. Finally, stereological correction indices were exclusively estimated from 2D measureable parameters obtained through the correlation. This model exhibited high versatility based on the all-encompassing simulation. The model was validated using nine different irregularly shaped binary particle systems and assessed using areal difference and maximum difference between liberation distribution curves in two and three dimensions. This error indices improved by approximately 80% for the former error index and 90% for the latter index.  相似文献   

20.
Block-diagonalization of the machine-component incidence matrix is the first step in the implementation of group technology. Even powerful algorithms will fail to achieve this if the matrix itself is not amenable to block-diagonalization. The present work analyses the properties of the matrix and identifies the standard deviation of the pairwise similarities (Jaccard7rpar; of the vectors as the major factor that decides the groupability of the data set. Many data sets ranging from the perfectly groupable to the most ill structured ones are analysed and presented. The groupability curves show the variation of the property against the relevant factors.  相似文献   

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