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排序方式: 共有1077条查询结果,搜索用时 11 毫秒
81.
This paper estimates the price-induced impacts of decarbonization policy on CO2 emissions in California and the Pacific Northwest. We document that retail demands for electricity and natural gas by customer class are highly price-inelastic. Based on the heat rates of natural-gas-fired generation, we find that a 10% electricity rate increase due to electricity decarbonization may not have the consumption effects of further reducing the region’s CO2 emissions. 相似文献
82.
Dr. Francesco A. Greco Dr. Elisa Albini Dr. Alice Coletti Dr. Daniela Dolciami Prof. Andrea Carotti Dr. Ciriana Orabona Prof. Ursula Grohmann Prof. Antonio Macchiarulo 《ChemMedChem》2019,14(24):2084-2092
Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the oxidative cleavage of l -Tryptophan (l -Trp) to yield N-formyl-kynurenine in the first and rate limiting step of the kynurenine pathway. Bioactive metabolites, involved in the regulation of important immunological responses and neurological processes, are then produced by downstream enzymes along the pathway. Inhibitors of IDO1 are being designed and developed as therapeutic agents for immuno-oncology. In this work, we investigated the molecular recognition path of l -Trp to IDO1, integrating biophysical methods with supervised molecular dynamics (suMD) and mutagenesis experiments. Results allowed disclosing for the first time high and low dissociation constants of l -Trp to IDO1, and the presence of a metastable interaction site located at the upper part of a channel whose borders are defined by the EF-loop and the C-terminal part of the JK-loop. Collectively, our results provide new clues for the design of next-generation IDO1 ligands. 相似文献
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Reports 2 studies, using a total of 304 university students, in which a likable or unlikable communicator delivered a persuasive message via writing, audiotape, or videotape. In both studies the likable communicator was more persuasive in video- and audiotape than in writing, but the unlikable communicator was more persuasive in writing. Thus, communicator likability was a significant determinant of persuasion only in the broadcast modalities. Other findings suggest that Ss process more communicator cues when exposed to video- and audiotape messages than when exposed to written ones and that communicator-based (rather than message-based) cognitions predicted opinion change primarily in video and audiotape conditions rather than in written ones. It is concluded that video- and audiotapes enhance communicator-related information, so that communicator characteristics exert a disproportionate effect on persuasion when messages are broadcast. Findings are also discussed in relation to "vividness" phenomena. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
A video database of moving faces and people 总被引:3,自引:0,他引:3
O'Toole AJ Harms J Snow SL Hurst DR Pappas MR Ayyad JH Abdi H 《IEEE transactions on pattern analysis and machine intelligence》2005,27(5):812-816
We describe a database of static images and video clips of human faces and people that is useful for testing algorithms for face and person recognition, head/eye tracking, and computer graphics modeling of natural human motions. For each person there are nine static "facial mug shots" and a series of video streams. The videos include a "moving facial mug shot," a facial speech clip, one or more dynamic facial expression clips, two gait videos, and a conversation video taken at a moderate distance from the camera. Complete data sets are available for 284 subjects and duplicate data sets, taken subsequent to the original set, are available for 229 subjects. 相似文献
86.
Zhao Ren Kun Qian Zixing Zhang Vedhas Pandit Alice Baird Bj?rn Schuller 《IEEE/CAA Journal of Automatica Sinica》2018,5(3):662-669
Spectrogram representations of acoustic scenes have achieved competitive performance for acoustic scene classification. Yet, the spectrogram alone does not take into account a substantial amount of time-frequency information. In this study, we present an approach for exploring the benefits of deep scalogram representations, extracted in segments from an audio stream. The approach presented firstly transforms the segmented acoustic scenes into bump and morse scalograms, as well as spectrograms; secondly, the spectrograms or scalograms are sent into pre-trained convolutional neural networks; thirdly, the features extracted from a subsequent fully connected layer are fed into (bidirectional) gated recurrent neural networks, which are followed by a single highway layer and a softmax layer; finally, predictions from these three systems are fused by a margin sampling value strategy. We then evaluate the proposed approach using the acoustic scene classification data set of 2017 IEEE AASP Challenge on Detection and Classification of Acoustic Scenes and Events (DCASE). On the evaluation set, an accuracy of 64.0% from bidirectional gated recurrent neural networks is obtained when fusing the spectrogram and the bump scalogram, which is an improvement on the 61.0% baseline result provided by the DCASE 2017 organisers. This result shows that extracted bump scalograms are capable of improving the classification accuracy, when fusing with a spectrogram-based system. 相似文献
87.
Auditory perception based system for age classification and estimation using dynamic frequency sound
Ilyas Muhammad Othmani Alice Nait-ali Amine 《Multimedia Tools and Applications》2020,79(29-30):21603-21626
Multimedia Tools and Applications - Human age is a crucial factor in social interaction. It determines the way we interact with others. It is also a relevant forensic issue that can provide helpful... 相似文献
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Sónia Cláudia Vitorino Cristina Gerald Francis Moore Priscila Raquel Fernandes Costa Goela John David Icely Alice Newton 《International journal of remote sensing》2013,34(6):2347-2377
Water-leaving reflectance (ρw) data from the European Space Agency ocean colour sensor Medium Resolution Imaging Spectrometer (MERIS) was validated with in situ ρw between October 2008 and November 2011, off Sagres on the southwest coast of the Iberian Peninsula. The study area is exceptional, since Stations A, B, and C at 2, 10, and 18 km offshore are in optically deep waters at approximately 40, 100, and 160 m, respectively. These stations showed consistently similar bio-optical properties, characteristic of Case 1 waters, enabling the evaluation of adjacency effects independent of the usual co-varying inputs of coastal waters. Using the third reprocessing of MERIS with the standard MEGS 8.1 processor, four different combinations of procedures were tested to improve the calibration between MERIS products and in situ data. These combinations included no vicarious adjustment (NoVIC), vicarious adjustment (VIC), and, for mitigating the effects of land adjacency on MERIS ρw, the improved contrast between ocean and land (ICOL) processor (version 2.7.4) and VIC + ICOL. Out of approximately 130 potential matchups for each station, 38–77%, 74–86%, and 88–90% were achieved at Stations A, B, and C, respectively, depending on which of the four combinations were used. Analyses of ρw comparing these various procedures, including statistics, scatter plots, histograms, and MERIS full-resolution images, showed that the VIC procedure compared with NoVIC produced minimal changes to the calibration. For example, at the oceanic Station C, the regression slope was closer to unity at all wavelengths with NoVIC compared to VIC, whereas, with the exception of wavelengths 412 and 443 nm, the intercept, mean ratio (MR), absolute percentage difference (APD), and relative percentage difference (RPD) were better with NoVIC. The differences for MR and APD indicate that there was marginal improvement for these two bands with VIC, and an over-adjustment with RPD. ICOL also showed inconsistent results for improving the retrieval of the near-shore conditions, but under some conditions, such as ρw at wavelength 560 nm, the improvement was striking. VIC + ICOL showed results intermediate between those of VIC and ICOL implemented separately. In relation to other validation sites, the offshore Station C at Sagres had much in common with the Mediterranean deep water, BOUSSOLE buoy, although the matchup statistics between MERIS ρw and in situ ρw were much better for Sagres than for BOUSSOLE. Strikingly, the matchup statistics for ρw at Sagres were very similar to those for the Acqua Alta Oceanographic Tower (AAOT), where the AAOT showed more scatter at 412 nm, probably because of the atmospheric correction where the aerosol optical thickness is higher at the AAOT. Conversely, Sagres showed much greater scatter at 665 nm in the red as the values were generally close to the limits of detection owing to the clearer waters at Sagres compared to the more turbid waters at the AAOT. 相似文献