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排序方式: 共有601条查询结果,搜索用时 0 毫秒
91.
This paper describes the Automated Reasoning for Mizar ( $\textsf{Miz}\mathbb{AR}$ ) service, which integrates several automated reasoning, artificial intelligence, and presentation tools with Mizar and its authoring environment. The service provides ATP assistance to Mizar authors in finding and explaining proofs, and offers generation of Mizar problems as challenges to ATP systems. The service is based on a sound translation from the Mizar language to that of first-order ATP systems, and relies on the recent progress in application of ATP systems in large theories containing tens of thousands of available facts. We present the main features of $\textsf{Miz}\mathbb{AR}$ services, followed by an account of initial experiments in finding proofs with the ATP assistance. Our initial experience indicates that the tool offers substantial help in exploring the Mizar library and in preparing new Mizar articles. 相似文献
92.
Fletcher Garth J. O.; Simpson Jeffry A.; Thomas Geoff 《Canadian Metallurgical Quarterly》2000,79(6):933
This research examined partner and relationship perceptions and ideal standards in 100 individuals over time, from the 1st to the 12th month of their dating relationships. As expected, the results revealed that (a) individuals evaluated their relationships on both distinct evaluative components and global evaluative dimensions, (b) higher ideal-perception consistency was associated with higher perceived quality of relationships and partners, (c) more positive perceptions of partners and relationships at earlier points in time were associated with more importance being placed on relevant ideals over time but not vice versa, and (d) higher levels of ideal-perception consistency predicted lower rates of relationship dissolution but were mediated through perceptions of relationship quality. These results support the ideal standards model (Fletcher & Simpson, in press). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Geoff Kelly 《Renewable & Sustainable Energy Reviews》2012,16(9):6851-6860
Residential energy consumption is now an important component of total energy consumption and its related emissions. In addition, this consumption has significant potential for growth in both developed and developing countries, as average incomes increase, and domestic appliance numbers rise. Reduction in this energy use may be achieved both through conservation measures, and through increased efficiency in its use. This paper focuses on energy efficiency in appliances—those many devices through which household energy is consumed. The policy instruments available to promote the uptake of more efficient devices, and issues associated with their use, are reviewed, drawing on developed country experiences to date. The instruments available are more limited than in other energy applications, and largely comprise information dissemination, forms of subsidy, and regulation. The last is commonly used in the form of minimum energy performance standards. Assessment of the three instrument types and issues with their use suggests that regulation is the most important measure—albeit with several qualifications on the manner of its use. 相似文献
94.
Near-Surface Wind-Induced Mixing in a Mine Lake 总被引:2,自引:0,他引:2
Anita Huber Gregory N. Ivey Geoff Wake Carolyn E. Oldham 《Canadian Metallurgical Quarterly》2008,134(10):1464-1472
Wind sheltering can have a strong effect in small, sheltered water bodies; wind-induced mixing in the surface layer of a small mine lake has been investigated using field measurements. Wind speed was recorded at three locations and data suggested sheltering by topography and surface roughness changes with both fetch and the land–water transition. Wind sheltering effects in the near-surface waters were assessed using turbulent microstructure profiler measurements, providing an estimate of the sheltering distance consistent with the literature on “backward-facing” steps. A numerical simulation of the annual density stratification cycle was then performed, using the model DYRESM. Simulations indicated that inclusion of a sheltering algorithm based on the results of the field campaign significantly improved the model’s performance in capturing the surface mixed layer deepening associated with strong wind events. 相似文献
95.
96.
There are great interests to capture the CO_2 to control the greenhouse gas emission. Amine absorption of CO_2 is being taken as an effective way to capture CO_2 in industry. However, the amine absorption of CO_2 is cost-ineffective due to great energy consumption and solution consumption. In order to reduce the capture cost, catalyst fluidization is proposed here to intensify the mass transfer and heat transfer. Catalyst fluidization with field synergy and DFT model is developed by incorporating the effects of catalyst reaction kinetics, drag force and multi-field into the mass transfer, heat transfer, fluid flow and catalyst collision. Experiments with an improved distributor are performed well to validate the model. The reaction kinetics is determined by the DFT simulation and experiment. The mass transfer coefficient in the fluidized reactor is identified as 17% higher than the conventional packed reactor. With the field synergy of catalyst fluidization, the energy consumption for CO_2 desorption is reduced by 9%. Stepwise operation and inclination reactor are used to improve catalyst fluidization process. 相似文献
97.
98.
Hynes EF Rudd CD Temple-Smith PD Sofronidis G Paris D Shaw G Renfree MB 《Reproduction (Cambridge, England)》2005,130(1):123-130
The tammar wallaby (Macropus eugenii) is a small, promiscuous, macropodid marsupial. Females usually produce a single young each year and there is a clear dominance hierarchy between adult males. The dominant male usually mates first and then guards the female to prevent access to her by other males. In this study, agonistic encounters and mating behaviour were observed to determine male dominance hierarchies in six groups of captive tammars consisting of a total of 23 males and 50 females. Mating behaviour was observed immediately post-partum when females were in oestrus and was correlated with plasma testosterone concentrations. Male mating sequences were recorded, and the paternity of offspring was determined by using seven macropodid marsupial microsatellites. Rates of sexual checking and aggression by males housed with females in oestrus in the non-breeding season were lower than in the breeding season. These males also had lower concentrations of testosterone, but were still able to sire young. High testosterone concentrations neither ensured dominance nor appeared to control directly the level of sexual activity. Females usually mated with more than one male. The dominant male most often secured the initial copulation (60%), but the first-mating male did not always secure parentage, with second and third matings resulting in as many young as first matings. Using these data, we were unable to discount first sire, last sire or equal chance models of paternity in this species. Half the young (50%) were sired by the dominant alpha male, but of the remaining progeny, the beta male sired more (35%) than gamma and delta males (15%). Dominance therefore is only a moderately effective predictor of paternity in the tammar. Although the dominant males gained most first matings and individually sired half of the offspring, the subdominant males still contributed significantly to the population, at least in captivity. 相似文献
99.
Bárbara E. Meza Amy K.S. ChestertonRoxana A. Verdini Amelia C. RubioloPeter A. Sadd Geoff D. MoggridgeD. Ian Wilson 《Journal of food engineering》2011,104(4):592-602
The rheological behaviour of high ratio cake batters prepared with untreated and heat-treated wheat flours was analysed at different stages of the manufacturing process, namely slurry, (on aeration) foams and (with fat addition) aerated emulsions, featuring air volume fractions up to 0.50. Both steady shear and viscoelastic behaviours were studied. All materials exhibited shear-thinning behaviour at 20 °C over the shear rate range studied (0.07-10 s−1). The generalised Cox-Merz rule could be applied to all samples. Materials prepared with heat-treated flours exhibited greater stability, as indicated by slurry thixotropy and cohesive energy, and the change in apparent viscosity and air content of foams and aerated emulsions on extended mixing. Foams and aerated emulsions showed significant elastic behaviour with G′∼G″. The temperature dependency of aerated emulsions was studied by oscillatory shear testing from 20 to 100 °C and indicated three regimes in temperature dependence: below 40 °C G′and G″ were insensitive to temperature; between 40 and 70 °C the complex viscosity exhibited Arrhenius-type behaviour, while above 70 °C G′ and G″ increased as expected for gelatinisation and foam setting. The weak gel model for foods was used to analyse the latter data sets and confirmed that the gel network generated in aerated emulsions prepared with heat-treated flours was significantly stronger than those made with unheated flours. The differences between flour types were also observed in tests on un- and heat-treated flours obtained from a second and third harvest. The impact of these quantifiable differences in rheology on performance during baking is discussed. 相似文献
100.