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991.
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993.
Concern over increased demand for petroleum, reliable fuel supply, and global climate change has resulted in the US government passing new Corporate Average Fuel Economy standards and a Renewable Fuels Standard. Consequently, the fuel mix for light duty vehicle (LDV) travel in the United States will change over the coming years. This paper explores the embodied water consumption and withdrawal associated with two projections for future fuel use in the US LDV sector. This analysis encompasses conventional and unconventional fossil fuels, corn ethanol, cellulosic ethanol, soy biodiesel, electricity, and hydrogen. The existing mandate in the US to blend ethanol into gasoline had effectively committed 3300 billion liters of irrigation water in 2005 (approximately 2.4% of US 2005 fresh water consumption) for producing fuel for LDVs. With current irrigation practices, fuel processing, and electricity generation, it is estimated that by 2030, approximately 14,000 billion liters of water per year will be consumed and 23,000–27,000 billion liters withdrawn to produce fuels used in LDVs. Irrigation for biofuels dominates projected water usage for LDV travel, but other fuels (coal to liquids, oil shale, and electricity via plug-in hybrid vehicles) will also contribute appreciably to future water consumption and withdrawal, especially on a regional basis. 相似文献
994.
Ilia Nouretdinov Dmitry Devetyarov Volodya Vovk Brian Burford Stephane Camuzeaux Aleksandra Gentry-Maharaj Ali Tiss Celia Smith Zhiyuan Luo Alexey Chervonenkis Rachel Hallett Mike Waterfield Rainer Cramer John F. Timms Ian Jacobs Usha Menon Alex Gammerman 《Annals of Mathematics and Artificial Intelligence》2015,74(1-2):203-222
995.
Thomas D. Weddell Yury M. Yarin Markus Drexl Ian J. Russell Stephen J. Elliott Andrei N. Lukashkin 《Journal of the Royal Society Interface》2014,11(93)
The round window (RW) membrane provides pressure relief when the cochlea is excited by sound. Here, we report measurements of cochlear function from guinea pigs when the cochlea was stimulated at acoustic frequencies by movements of a miniature magnet which partially occluded the RW. Maximum cochlear sensitivity, corresponding to subnanometre magnet displacements at neural thresholds, was observed for frequencies around 20 kHz, which is similar to that for acoustic stimulation. Neural response latencies to acoustic and RW stimulation were similar and taken to indicate that both means of stimulation resulted in the generation of conventional travelling waves along the cochlear partition. It was concluded that the relatively high impedance of the ossicles, as seen from the cochlea, enabled the region of the RW not occluded by the magnet, to act as a pressure shunt during RW stimulation. We propose that travelling waves, similar to those owing to acoustic far-field pressure changes, are driven by a jet-like, near-field component of a complex pressure field, which is generated by the magnetically vibrated RW. Outcomes of research described here are theoretical and practical design principles for the development of new types of hearing aids, which use near-field, RW excitation of the cochlea. 相似文献
996.
Nicholas Merriam Peter Gliwa Ian Broster 《International Journal on Software Tools for Technology Transfer (STTT)》2013,15(1):9-28
Observing the timing properties of actual software provides information not derivable from pure modelling of the hardware, software and test data. Equally, modelling provides worst-case timing values that cannot be realistically determined from only testing and measurement. From this observation, we develop a combined methodology, where measured and modelled results are used in turn to build a complete, unified approach to software timing analysis. Beyond this, we develop toward a powerful and symbiotic process, where that data can be freely and reliably exchanged, and that is greater than the obvious sum of the parts. 相似文献
997.
Christopher J. Pillidge Lucy M. Sheehy Amal Shihata Zhao-Yan Pu Marian Dobos Ian B. Powell 《International Dairy Journal》2009,19(4):222-227
Partial 16S rRNA gene sequencing of Lactococcus lactis subsp. cremoris strains from our collection identified strains containing sequences diagnostic of both subspecies L. lactis subsp. lactis and L. lactis subsp. cremoris together in the same strain. The presence of a plasmid-encoded 16S rRNA pseudogene partly explained this result. Twenty-four out of 46 L. lactis subsp. cremoris strains tested by PCR contained this pseudogene. However, further analysis showed that five of these 24 strains also contained chromosomal 16S rRNA genes with sequences typical of L. lactis subsp. lactis. Genetic and phenotypic tests indicated these strains were otherwise normal L. lactis subsp. cremoris strains. Past recombination events between the 16S rRNA pseudogene and chromosomal 16S rRNA genes may explain this phenomenon. Genomic heterogeneity for both 16S rRNA and other gene sequences was observed for L. lactis subsp. cremoris SK11 from different laboratories, indicating caution is needed when integrating data from diverse sources for nominally the same strain. 相似文献
998.
Economic performance assessment of control systems is receiving increasing attention in both academia and industry. A relevant framework is proposed in Bauer and Craig (Bauer, M., Craig, I.K., 2008. Economic assessment of advanced process control – a survey and framework. Journal of Process Control 18 (1), 2–18) based on a comprehensive survey of the methods for economic analysis of advanced process control systems. The framework provides a formal procedure for the economic assessment of control systems. A practically motivated simulation study is used to cast the economic performance assessment of a nonlinear model predictive controller and three single-loop PID controllers for a run-of-mine milling circuit into this framework. Performance functions of the milling circuit, which dynamically relate the circuit process variables to monetary values, are developed based on a survey study on milling circuits and an in-depth literature study. 相似文献
999.
Daniel Cozzolino Allison Chree Ian Murray Jeff R. Scaife 《International Journal of Food Science & Technology》2009,44(8):1579-1584
The objective of this study was to explore the use of near infrared (NIR) spectroscopy and chemometrics to monitor the degree of heat treatment of fish meal. Six batches of fish meal (approximately 500 g) were split in sub‐samples of 50 g and heated at constant temperature (60 ± 5 °C) for different periods of time (15 and 30 min, 1, 2, 3, 4, 5, 6, 8, 48 and 72 h) in a force air oven and scanned in the NIR region (1100–2500 nm) in a monochromator instrument in reflectance. Principal component analysis (PCA), stepwise discriminant analysis (SLDA) and partial least square regression (PLS) models were used to interpret, classify and predict the extent to heat treatment in fish meal samples. The SLDA models correctly classified 80% and 100% of fish meal samples belonging to the untreated fish meal and after 4, 5 and 6 h of heat treatment. However, samples heated for 30 min, 1, 2 and 3 h yield poor classification rates (less than 50%). This study demonstrated the potential ability of NIR spectroscopy to predict and classify the extent of heat treatment during the production of fish meal. However, further research must carry out in order to validate the NIR calibrations to predict the degree of heat treatment in fish meal expose to a shorter time. 相似文献
1000.
New Zealand has an array of geothermal systems with distinctive ecological features, with many occurring in the Taupo Volcanic Zone in the Central North Island. Associated with these geothermal features are characteristic geophysical and geochemical components, and distinctive terrestrial and aquatic ecosystems with many attributes that are common across a range of the biotic groups. Zonation amongst vegetation communities is closely related to soil temperature and these associations generally occur in a predictable sequence along the soil temperature gradient. Similarly, clear distinctions in aquatic flora and fauna occur longitudinally downstream from the source of thermal springs and vertically on geyser mounds. 相似文献