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101.
In a marine coastal ocean monitoring and prediction system, multisensor in-situ and remote sensing observations (of coastal currents, fronts, eddies, upwelling patterns, internal waves, phytoplankton distribution, algae patchiness, oil pollution and high-resolution wind fields) need integration and combination with fine resolution numerical ocean models. Only via such integrated systems will realistic representation of the initial state be derived and properly utilized to provide reliable and accurate forecasts of, for instance, location of eddies, upwelling patterns, and high-concentration of toxic algae. The role of sar in such systems is addressed and characterized in terms of current status and further need for research and development. Use of synergetic remote sensing observations, in particular from optical remote sensing, is also considered in this context.  相似文献   
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Exposure assessment of mycotoxins in dairy milk   总被引:1,自引:0,他引:1  
The objective of this study was to develop a quantitative Monte Carlo exposure assessment model for mycotoxins in dairy milk and to assess the potential human exposure levels. Mean concentrations of mycotoxins in milk were estimated using the simulation model (Aflatoxin M1 = 0.0161 μg/kg, Ochratoxin A = 0.0002 μg/kg, Deoxynivalenol = 1 μg/kg, Fumonisin B1 = 0.36 μg/kg, Zearalenone = 0.39 μg/kg, T-2 = 0.0722 μg/kg) while the simulated tolerable daily intakes (TDIs) from milk for males and females all fell below European Union guidelines. Aflatoxin M1 was the toxin of greatest concern as it had potential to exceed the EU limit of 0.05 μg/kg in milk. The sensitivity analysis identified the concentration of toxins in maize as the area which needs most attention in relation to crop management and agricultural practice. The sensitivity analysis assessed also identified the carry over rate as a factor closely related to risk and as a factor which required further research.  相似文献   
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Current transformer saturation can cause protective relay misoperation or even prevent tripping. This paper presents the use of artificial neural networks (ANN) to correct current transformer (CT) secondary waveform distortions. The ANN is trained to achieve the inverse transfer function of iron-core toroidal CTs which are widely used in protective systems. The ANN provides a good estimate of the true (primary) current of a saturated transformer. The neural network is developed using MATLAB and trained using data from EMTP simulations and data generated from actual CTs. In order to handle large dynamic ranges of fault currents, a technique of employing two sets of network coefficients is used. Different sets of network coefficients deal with different fault current ranges. The algorithm for running the network was implemented on an Analog Devices ADSP3101 digital signal processor. The calculating speed and accuracy proved to be satisfactory in real-time application  相似文献   
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Reports an error in the original article by D. D. Cummins (Journal of Experimental Psychology: Learning, Memory, and Cognition, 1992[Sep], Vol 18[5], 1103–2124). On page 1111, there are labeling errors in 2 figures. In Figure 1c, problem 11 should have a "V' in the topic column; that line should read "11 V Fl.' In Figure 1d, problems 2 and 4 should have "CU' in the structure column; those lines should read "2 T CU' and "4 T CU,' respectively. Also in that figure, problems number 8 and 13 should have "Fl' in the structure column; those lines should read "8 V Fl' and "13 W Fl.' (The following abstract of this article originally appeared in record 1993-04297-001.) In 3 experiments, novices were required to answer questions while reading a series of problems. The questions required them either to analyze individual problem structures (intraproblem processing) or compare problem structures (analogical comparison processing) to derive answers … (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
Combining HB vaccine with routine paediatric vaccines has been recognized as the best means of universal vaccination against hepatitis B. Our objective was to evaluate the long-term antibody persistence of such a combined vaccine in an area of high hepatitis B endemicity. We have shown that a DTPw-HB vaccine was safe and immunogenic when given as a booster dose at 18 months of age. One month after the booster dose of DTPw-HB vaccine, at least 97.8% of subjects had seroprotective anti-HBsAg levels, and 1 year later at least 93.9% of these subjects remained seroprotected against HBsAg. Immune responses to the DTPw components were similar or greater than those of the commercial DTPw vaccine given to the control group. This DTPw-HB vaccine, which showed good long-term anti-HBsAg antibody persistence, could advantageously replace separate DTPw and HB vaccines in areas of high hepatitis B endemicity in terms of clinical, economic and strategic benefits.  相似文献   
110.
Silver (Ag) nanoparticles (NPs) were synthesised and characterised, and their antimicrobial activity against Escherichia coli, Staphylococcus aureus, Bacillus cereus, Pseudomonas fluorescens and microflora derived from raw chicken, beef or cooked ham was determined. Polyvinyl chloride (PVC) films or antimicrobial Ag/PVC nanocomposite films were manufactured via a solvent casting method and the mechanical and thermal properties of these materials determined. Manufactured antimicrobial Ag/PVC nanocomposite films were used to wrap chicken breast fillets, followed by modified atmosphere packaging (using conventional laminates and employing a gas mix of 60 % N2/40 % CO2), and compared against PVC control films. In general, Gram-negative bacteria were more sensitive to Ag NPs than Gram-positive bacteria and microflora isolated from meat products were more resistant than pure culture bacteria. However, the most sensitive bacteria to Ag NPs were Pseudomonas fluorescens. No significant differences (p?>?0.05) in tensile strength and elongation at break were observed, but glass transition temperatures (T g) of Ag/PVC nanocomposite films were lower (p?<?0.05) when compared to PVC control films. Results also indicated that antimicrobial Ag/PVC nanocomposite films significantly (p?<?0.05) extended the shelf-life of chicken breast fillets and reduced lipid oxidation of chicken breast fillets compared to PVC-wrapped equivalents. Overall, results indicated that antimicrobial Ag/PVC nanocomposite films can potentially be used as antimicrobial packaging for food packaging applications.  相似文献   
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