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991.
In this paper we investigate the position of a review network within a research specialty; the network of scholars who write
reviews of their colleagues’ work. This is one of the voluntary activities that researchers perform as a prerequisite for
the functioning of the invisible college. We compare this network to other networks within the specialty, and this allows
us to distinguish various roles: stars, influentials, members, reviewers and juniors. As scholars are characterized by different role-configurations, the invisible college becomes stratified. We discuss the
implications for the development of a referee factor and review factor, norms for refereeing and reviewing, and the development
of systems-based research evaluations. 相似文献
992.
993.
Juan Xing Pham Van Hung Stephen Symons Muhammad Shahin David Hatcher 《Sensing and Instrumentation for Food Quality and Safety》2009,3(4):211-218
Sprout damage (pre-harvest germination) in wheat results in highly deleterious effects on end-product quality. Alpha-amylase,
the pre-dominant enzyme in the early stage of sprouting has the most damaging effect. This paper introduces a new method using
a SWIR hyperspectral imaging system (1000–2500 nm) to predict the α-amylase activity of individual wheat kernels. Two classes
of Canadian wheat, Canada Western Red Spring (CWRS) and Canada Western Amber Durum (CWAD), with samples of differing degrees
of sprout damage were investigated. Individual kernels were first imaged with the hyperspectral imaging system and then the
α-amylase activity of each kernel was determined analytically. Individual kernel α-amylase activity prediction was significant
(R
2 0.54 and 0.73) for CWAD and CWRS, respectively using Partial Least Square regression on the hyperspectral data. A classification
method is proposed to separate CWRS kernels with high α-amylase activity level from those with low α-amylase activity giving
an accuracy of above 80%. This work shows that hyper/multi-spectral imaging techniques can be used for rapidly predicting
the α-amylase activity of individual kernels, detecting sprouting at early stage. 相似文献
994.
Bogdan C. Donose Elena Taran Marc A. Hampton Stoyan I. Karakashev Anh V. Nguyen 《Advanced Powder Technology》2009,20(3):257-261
Interaction forces between a multi-walled carbon nanotube (MWCNT) and an air-bubble in pure deionized water and methyl isobutyl carbinol (MIBC) solutions were measured by atomic force microscopy (AFM). The MWCNT terminated probe was brought into contact with the bubble at controlled applied forces. The repulsive steps followed by attractive jumps recorded in the approach force curves correspond to changes in the MWCNT diameter along its length, an observation confirmed by transmission electron microscopy (TEM) data. By processing the retraction part of the force curves obtained in pure water it is possible to estimate the end diameter of the carbon nanotube with nanometer resolution using a capillary force model. 相似文献
995.
Nguyen Thi Huong Lien Hajime Nobuhara Fangyan Dong Kaoru Hirota 《Signal, Image and Video Processing》2009,3(2):115-126
To robustly and imperceptibly embed copyright information as a watermark into music clips, a two channel digital watermarking
system based on the least significant bit (LSB) method and echo hiding (EH) with a new exponential time-spread echo kernel
(ETEK) is proposed. By spreading the echo so that it seems like natural room reverberation, as well as the use of two channels
to separately watermark by the LSB method and the EH method which have complementary characteristics, the system provides
satisfactory sound quality and exhibits both efficient retrieval capacity and robustness against attacks. Experiments show
that the proposed system retrieves watermarks with 100% accuracy for all clips and is almost imperceptible. With a set of
42 attacks supplied by the StirMark Benchmark for Audio (SMBA), the proposed system has an average robustness of 0.98 where
the ideal value is 1.00, and higher than any conventional methods. With these results, the proposed system is shown to be
possible for the application to music distribution over the Internet. 相似文献
996.
997.
In this paper, we consider the problem of scheduling lightpaths and computing resources for sliding grid demands in WDM networks. Each sliding grid demand is represented by a tuple (v,R,c,p,q,l) , where v is the client node, R is the resource-group which includes a group of predefined resource nodes, c is the required amount of computing resources, [p,q] is the time window and l is the demand duration. With each demand, the scheduling algorithm is required to decide the start time t (p les t les q - l), reserve an amount of c computing resources at a resource node v ' isin R and provision a primary lightpath as well as a backup lightpath from v ' to v . The reserved computing resources and lightpaths are used during [t,t + l]. Unlike the sequential approach wherein the start time, the network resources (lightpaths) and the computing resources are considered one after another, in our work we use the joint scheduling approach wherein the resources and the start time are examined jointly. We consider sliding demands with static and dynamic arrival patterns. We develop an integer linear programming (ILP) formulation to obtain optimal results. For the reason of scalability, we propose heuristic algorithms based on joint resource scheduling and study their effectiveness through simulation experiments. 相似文献
998.
Min Li Bruno Bougard Liesbet Van Der Perre Francky Catthoor 《Journal of Signal Processing Systems》2009,56(2-3):327-340
The flexibility and programmability of SDR come at the expense of reduced efficiency and increased energy consumption. This is usually considered as the penalty of SDR. However, the flexibility and programmability have great potentials for improving the system-wide efficiency if they are properly exploited. In this paper, we present a HSDPA chip equalizer that is explicitly designed for SDR implementations. The first SDR-specific feature of our work is the multi-mode operation based on heterogeneous algorithms. The proposed equalizer combines an optimized LMS variant (with subspace-aware extension) and an optimized SRI-RLS algorithm based on QRD. Instead of always applying the powerful SRI-RLS algorithm, the equalizer switches to simple LMS-variant when possible. With negligible BER degradation, the multi-mode operation can reduce 60% of the cycle-count on TI TMS320C6713 for 3GPP case 4 with 16QAM modulation. The proposed equalizer framework also incorporates a generic, robust and efficient scheme for equalization-length adaptation. The length-adaptation scheme can make very fast run-time decision based on an efficient policy-template, which is optimized with large training set at design time. We test 14 representative channel profiles specified in ITU-R M.1225, 3GPP TR 25.943 and 3GPP TS 25.101. Comparing to worst-case based design the length-adaptation achieves more than 10× cycle-count reductions for ten of the cases. 相似文献
999.
Two experiments examined solicitation of information in a group structured as a judge–advisor system (JAS) with 1 group member designated as the decision maker and the other 2 members as advisors. The decision maker solicited information from 2 advisors. One advisor's information was shared in common with the decision maker, and the other's information was predominantly unshared. In 2 experiments, decision makers asked for more information from the advisor with unshared information and rated this advisor's information as more important and influential than the advisor with only redundant, shared information. When decision makers were not limited in the amount of information they could ask for, decision makers significantly increased requests for information from the advisor with shared information but not the advisor with unshared information. Experiment 2 found that whether or not an advisor agreed with the decision maker did not affect decision makers' preference for the advisor with unshared information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
R. Adam Rebeles P. Van den Winkel F. Tárkányi 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(3):457-461
One of the radioisotopes for which a growing interest exists in nuclear medicine is 64Cu. Its branched decay makes it suitable for both diagnostic and therapeutic purposes. Activation cross sections of the proton induced reaction on enriched 64Ni have been studied using the stacked foil technique up to 24 MeV. The experimental cross sections are compared with values available from literature. Thick target yields, based on the discrete measured values of the cross sections are calculated and allow a better estimation of the optimum production parameters. 相似文献