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41.
42.
Physical, chemical and palynological characterization of avocado (Persea americana Mill.) honey in Israel 总被引:1,自引:0,他引:1
Arnon Dag Ohad Afik Yelena Yeselson Arthur Schaffer & Sharoni Shafir 《International Journal of Food Science & Technology》2006,41(4):387-394
Various methods were used to characterize avocado honey in Israel. Perseitol, a unique sugar present only in avocado honey, served as an indicator for the degree of purity of avocado honey. Low avocado pollen counts made the common melissopalynology method ineffective at predicting the contribution of avocado nectar to honey. It was also found that the levels of fructose, sucrose and glucose do not uniquely characterize avocado honey. Potassium content and eight other minerals were linearly highly correlated to perseitol content. Moreover, pH level, absorbance and degree of darkness were significantly correlated to perseitol content, and can therefore be used to characterize avocado honey. 相似文献
43.
Secure reliable multicast protocols in a WAN 总被引:1,自引:0,他引:1
Summary. A secure reliable multicast protocol enables a process to send a message to a group of recipients such that all correct destinations
receive the same message, despite the malicious efforts of fewer than a third of the total number of processes, including
the sender. This has been shown to be a useful tool in building secure distributed services, albeit with a cost that typically
grows linearly with the size of the system. For very large networks, for which this is prohibitive, we present two approaches
for reducing the cost: First, we show a protocol whose cost is on the order of the number of tolerated failures. Secondly,
we show how relaxing the consistency requirement to a probabilistic guarantee can reduce the associated cost, effectively
to a constant.
Received: August 1997 / Accepted: July 1999 相似文献
44.
The authors consider a selective repeat (SR) automatic-repeat-request (ARQ) protocol with one source and multiple receivers. Each receiver acknowledges all packets and handles its resequencing buffer based only on the packets that it receives error-free. An analysis of the resequencing delay and buffer occupancy at a receiver is presented. The authors construct a model that makes it possible to derive steady-state results, taking into consideration such system parameters as number of receivers, propagation delay, packet error probabilities, and acknowledgments. The authors focus on two measures of occupancy. The first measure corresponds to the number of packets waiting to be resequenced whereas the second measure includes, in addition, the buffer space reserved for packets that cause resequencing delays. The main results are the distribution of the resequencing delay and the distribution of the number of packets occupying the receiver's buffer 相似文献
45.
A communications system in which multiple parallel channels are available to carry traffic from a transmitter to a receiver is considered, and an extension of the selective-repeat automatic repeat request (SR-ARQ) protocol that dynamically assigns packets to channels for each (re)transmission is presented. Because of selective retransmission, packets arrive at the receiver out of order and must be stored in a resequencing buffer. A queuing model for the resequencing buffer is constructed. The generating function of the buffer occupancy and the packet-delay distribution are derived, and procedures for simplifying the computation are presented. The dynamic assignment scheme is compared with, and shown to have performance superior to, a static assignment scheme 相似文献
46.
In this paper we introduce an imaging system based on a reflective phase-only spatial light modulator (SLM) in order to perform imaging with improved geometric resolution. By using the SLM, we combine the realization of two main abilities: a lens with a tunable focus and a phase function that, after proper free-space propagation, is projected as an amplitude distribution on top of the inspected object. The first ability is related to the realization of a lens function combined with a tunable prism that yields a microscanning of the inspected object. This by itself improves the spatial sampling density. The second ability is related to a projection of a phase function that is computed using an iterative beam-shaping Gerchberg-Saxton algorithm. After the free-space propagation from the SLM toward the inspected object, an amplitude pattern is generated on top of the object. This projected pattern and a set of low-resolution images with relative shift are interlaced and, after applying the proper regularization method, a geometrically superresolved image is reconstructed. 相似文献
47.
Mordechai Shacham Inga Paster Neima Brauner 《American Institute of Chemical Engineers》2013,59(2):420-428
Data analysis and prediction of pure component properties of long‐chain substances is considered. The emphasis is on homologous series and properties for which insufficient data are available. A two‐stage procedure is recommended, whereby a linear (or nonlinear) quantitative structure–property relationship (QSPR) is fitted to a “reference” series, for which an adequate amount of precise data is available. This QSPR should represent correctly both the available data and the asymptotic behavior of the property. In the second stage a quantitative property‐property relationship (QPPR) is derived to represent the predicted property values of a “target” series in terms of the property values of the reference series. The procedure is applied for properties which are highly correlated with the number methylene groups in homologous series: and . It is shown that the method is very useful for consistency analysis of property data and enables a reliable prediction of and , and, thus, also of for long‐chain substances. © 2012 American Institute of Chemical Engineers AIChE J, 59: 420–428, 2013 相似文献
48.
Dr. Emmanuelle Briard Dr. Aniket D. Joshi Dr. Shiva Shanmukhappa Dr. Ohad Ilovich Dr. Yves P. Auberson 《ChemMedChem》2019,14(16):1493-1502
Autotaxin (ATX) is a secreted enzyme with tissue levels associated with tissue injury, which increase during wound healing and chronic fibrotic diseases. We selected [18F](R,E)-3-(4-chloro-2-((5-methyl-2H-tetrazol-2-yl)methyl)phenyl)-1-(4-((5-(2-fluoroethoxy)pyridin-2-yl)methyl)-2-methylpiperazin-1-yl)prop-2-en-1-one ([18F]PRIMATX, [18F] 2 ), a tracer for positron emission tomography, to image ATX expression in vivo. It successfully differentiates expression levels in lung tissue samples from idiopathic pulmonary fibrosis patients, and allows the detection of ATX-expressing tumors in living mice, confirming its potential for development as a clinical imaging agent. 相似文献
49.
An Experimental Validation of a Wavelength-Striped, Packet Switched, Optical Interconnection Network
We experimentally validate a complete optical packet switched interconnection network, implementing the SPINet architecture. The scalable photonic integrated network (SPINet) architecture capitalizes on wavelength division multiplexing (WDM) to provide very large transmission bandwidths, simplify network design, and reduce the network's power dissipation. Contention resolution is performed in the optical domain, and a novel physical layer acknowledgement protocol is employed to mitigate the associated latency and performance penalties. Moreover, the SPINet architecture is specifically designed to enable on-chip integration by not using any kind of optical delay lines. Experiments presented include a complete functionality verification, error-free routing of 80 Gb/s wavelength-striped optical packets (8 wavelengths each modulated at 10 Gb/s) with a bit-error rate (BER) better than 10-12, and novel performance-enhancement techniques such as path adjustments and load balancing. 相似文献
50.
Neurons in primary visual cortex respond selectively to oriented stimuli such as edges and lines. The long-range horizontal connections between them are thought to facilitate contour integration. While many physiological and psychophysical findings suggest that collinear or association field models of good continuation dictate particular projection patterns of horizontal connections to guide this integration process, significant evidence of interactions inconsistent with these hypotheses is accumulating. We first show that natural random variations around the collinear and association field models cannot account for these inconsistencies, a fact that motivates the search for more principled explanations. We then develop a model of long-range projection fields that formalizes good continuation based on differential geometry. The analysis implicates curvature(s) in a fundamental way, and the resulting model explains both consistent data and apparent outliers. It quantitatively predicts the (typically ignored) spread in projection distribution, its nonmonotonic variance, and the differences found among individual neurons. Surprisingly, and for the first time, this model also indicates that texture (and shading) continuation can serve as alternative and complementary functional explanations to contour integration. Because current anatomical data support both (curve and texture) integration models equally and because both are important computationally, new testable predictions are derived to allow their differentiation and identification. 相似文献