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61.
This analysis explores the impact that the evolution of retail electricity tariffs can have on the deployment of solar photovoltaics. It suggests that ignoring the evolution of tariffs resulted in up to a 36% higher prediction of the capacity of distributed PV in 2050, compared to scenarios that represented tariff evolution. Critically, the evolution of tariffs had a negligible impact on the total generation from PV—both utility-scale and distributed—in the scenarios that were examined. 相似文献
62.
An understanding of land use/land cover change at local, regional, and global scales is important in an increasingly human-dominated biosphere. Here, we report on an under-appreciated complexity in the analysis of land cover change important in arid and semi-arid environments. In these environments, some land cover types show a high degree of inter-annual variability in productivity. In this study, we show that ecosystems dominated by non-native cheatgrass (Bromus tectorum) show an inter-annual amplified response to rainfall distinct from native shrub/bunch grass in the Great Basin, US. This response is apparent in time series of Landsat and Advanced Very High Resolution Radiometer (AVHRR) that encompass enough time to include years with high and low rainfall. Based on areas showing a similar amplified response elsewhere in the Great Basin, 20,000 km2, or 7% of land cover, are currently dominated by cheatgrass. Inter-annual patterns, like the high variability seen in cheatgrass-dominated areas, should be considered for more accurate land cover classification. Land cover change science should be aware that high inter-annual variability is inherent in annual dominated ecosystems and does not necessarily correspond to active land cover change. 相似文献
63.
64.
Rittle-Johnson Bethany; Star Jon R.; Durkin Kelley 《Canadian Metallurgical Quarterly》2009,101(4):836
Comparing multiple examples typically supports learning and transfer in laboratory studies and is considered a key feature of high-quality mathematics instruction. This experimental study investigated the importance of prior knowledge in learning from comparison. Seventh- and 8th-grade students (N = 236) learned to solve equations by comparing different solution methods to the same problem, comparing different problem types solved with the same solution method, or studying the examples sequentially. Unlike in past studies, many students did not begin the study with equation-solving skills, and prior knowledge of algebraic methods was an important predictor of learning. Students who did not attempt algebraic methods at pretest benefited most from studying examples sequentially or comparing problem types, rather than from comparing solution methods. Students who attempted algebraic methods at pretest learned more from comparing solution methods. Students may need sufficient prior knowledge in a domain before they benefit from comparing alternative solution methods. These findings are in line with findings on the expertise-reversal effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
Riefer David M.; Knapp Bethany R.; Batchelder William H.; Bamber Donald; Manifold Victor 《Canadian Metallurgical Quarterly》2002,14(2):184
This article demonstrates how multinomial processing tree models can be used as assessment tools to measure cognitive deficits in clinical populations, This is illustrated with a model developed by W. H. Batchelder and D. M. Riefer (1980) that separately measures storage and retrieval processes in memory. The validity of the model is tested in 2 experiments, which show that presentation rate affects the storage of items (Experiment 1) and part-list cuing hurts item retrieval (Experiment 2). Experiments 3 and 4 examine 2 clinical populations: schizophrenics and alcoholics with organic brain damage. The model reveals that each group exhibits deficits in storage and retrieval, with the retrieval deficits being stronger and occurring more consistently over trials. Also, the alcoholics with organic brain damage show no improvement in retrieval over trials, although their storage improves at the same rate as a control group. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
Olatunji Bunmi O.; Ciesielski Bethany G.; Armstrong Thomas; Zald David H. 《Canadian Metallurgical Quarterly》2011,11(5):1073
Although facial expressions are thought to vary in their functional impact on perceivers, experimental demonstration of the differential effects of facial expressions on behavior are lacking. In the present study, we examined the effects of exposure to facial expressions on visual search efficiency. Participants (n = 31) searched for a target in a 12 location circle array after exposure to an angry, disgusted, fearful, happy, or neutral facial expression for 100 ms or 500 ms. Consistent with predictions, exposure to a fearful expression prior to visual search resulted in faster target identification compared to exposure to other facial expressions. The effects of other facial expressions on visual search did not differ from each other. The fear facilitating effect on visual search efficiency was observed at 500-ms but not at 100-ms presentations, suggesting a specific temporal course of the facilitation. Subsequent analysis also revealed that individual differences in fear of negative evaluation, trait anxiety, and obsessive–compulsive symptoms possess a differential pattern of association with visual search efficiency. The experimental and clinical implications of these findings are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
67.
Propene is widely used in smog chamber experiments to increase the hydroxyl radical (OH) level based on the assumption that the formation of secondary organic aerosol (SOA) from parent hydrocarbon is unaffected. A series of m-xylene/NO(x) photooxidation experiments were conducted in the presence of propene in the University of California CE-CERT atmospheric chamber facility. The experimental data are compared with previous m-xylene/N0(x) photooxidation work performed in the same chamber facility in the absence of propene (Song et al. Environ. Sci. Technol. 2005, 39, 3143-3149). The result shows that, for similar initial conditions, experiments with propene have lower reaction rates of m-xylene than those without propene, which indicates that propene reduces OH in the system. Furthermore, experiments with propene showed more than 15% reduction in SOA yield compared to experiments in the absence of propene. Additional experiments of m-xylene/ NO(x) with CO showed similar trends of suppressing OH and SOA formation. These results indicate that SOA from m-xylene/NO(x) photooxidation is strongly dependent on the OH level present, which provides evidence for the critical role of OH in SOA formation from aromatic hydrocarbons. 相似文献
68.
The application of single photon ionization in combination with mass-selective detection by time-of-flight mass spectrometry is described for the rapid detection of the nitro-containing explosives and explosives-related compounds nitrobenzene, 1,3-dinitrobenzene, o-nitrotoluene, 2,4-dinitrotoluene, and 2,4,6-trinitrotoluene, as well as the peroxide-based explosive triacetone triperoxide in the gas phase. The technique is demonstrated to be a plausible approach for laser-based rapid detection of explosives. The limits of detection for nitrobenzene and 2,4-dinitrotoluene using SPI were also measured and determined to be 17-24 (S/N approximately 2:1) and approximately 40 ppb (S/N approximately 2:1), respectively. 相似文献
69.
Brand Bethany L.; Armstrong Judith G.; Loewenstein Richard J.; McNary Scot W. 《Canadian Metallurgical Quarterly》2009,1(3):188
Patients with dissociative identity disorder (DID) are often diagnosed with borderline personality disorder (BPD) and misdiagnosed with psychotic illnesses. This study is designed to determine whether the Rorschach protocols of 67 patients with DID differ from those of 40 patients with BPD and 43 patients with psychotic disorder (PSD) in variables reflecting capacity for working alliance, complexity of experience, and ability to reason despite traumatic flooding. As theoretically and clinically predicted, the DID group could be distinguished from the PSD sample by the DID group’s significantly higher level of traumatic associations alongside their more logical reasoning (e.g., Trauma Content Index [TCI], WSUM6). In comparison to the BPD group who, by definition, were also likely to dissociate and struggle with other trauma based symptoms, the DID sample showed greater social interest (Sum H), self-reflective capacity (FD; Form Dimension), ability to perceive more accurately and think more logically (X-, WSUM6). The authors discuss the treatment applications of these findings and make suggestions for further research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献