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排序方式: 共有2135条查询结果,搜索用时 15 毫秒
131.
This paper introduces local distance-based generalized linear models. These models extend (weighted) distance-based linear models first to the generalized linear model framework. Then, a nonparametric version of these models is proposed by means of local fitting. Distances between individuals are the only predictor information needed to fit these models. Therefore, they are applicable, among others, to mixed (qualitative and quantitative) explanatory variables or when the regressor is of functional type. An implementation is provided by the R package dbstats, which also implements other distance-based prediction methods. Supplementary material for this article is available online, which reproduces all the results of this article. 相似文献
132.
Impact of the Nanoscale Gap Morphology on the Plasmon Coupling in Asymmetric Nanoparticle Dimer Antennas 下载免费PDF全文
Paul S. Popp Janning F. Herrmann Eva‐Corinna Fritz Bart Jan Ravoo Christiane Höppener 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(12):1667-1675
Coupling of plasmon resonances in metallic gap antennas is of interest for a wide range of applications due to the highly localized strong electric fields supported by these structures, and their high sensitivity to alterations of their structure, geometry, and environment. Morphological alterations of asymmetric nanoparticle dimer antennas with (sub)‐nanometer size gaps are assigned to changes of their optical response in correlative dark‐field spectroscopy and high‐resolution transmission electron microscopy (HR‐TEM) investigations. This multimodal approach to investigate individual dimer structures clearly demonstrates that the coupling of the plasmon modes, in addition to well‐known parameters such as the particle geometry and the gap size, is also affected by the relative alignment of both nanoparticles. The investigations corroborate that the alignment of the gap forming facets, and with that the gap area, is crucial for their scattering properties. The impact of a flat versus a rounded gap structure on the optical properties of equivalent dimers becomes stronger with decreasing gap size. These results hint at a higher confinement of the electric field in the gap and possibly a different onset of quantum transport effects for flat and rounded gap antennas in corresponding structures for very narrow gaps. 相似文献
133.
Based on social role theory and uses and gratifications, this study provides insights into the popularity of so-called pink games. This study is the first to examine the roles of identification, playing time, and age in the experience of motivations while playing an online role-playing game. Drawing upon a survey among 2261 girls between10 and 17 of age, our results show that identification with characters in the game is an important process in explaining girls’ gaming motivations. In addition, identification and motivations are intensified with playing time. Although age affects identification negatively, age is not related to the most important motive in playing pink games: social interaction. This study has important theoretical and practical implications for the popularity of pink games among girls. 相似文献
134.
Emotions play a central role in our daily lives, influencing the way we think and act, our health and sense of well-being, and films are by excellence the form of art that exploits our affective, perceptual and intellectual activity, holding the potential for a significant impact. Video is becoming a dominant and pervasive medium, and online video a growing entertainment activity on the web and iTV, mainly due to technological developments and the trends for media convergence. In addition, the improvement of new techniques for gathering emotional information about videos, both through content analysis or user implicit feedback through user physiological signals complemented in manual labeling from users, is revealing new ways for exploring emotional information in videos, films or TV series, and brings out new perspectives to enrich and personalize video access. In this work, we reflect on the power that emotions have in our lives, on the emotional impact of movies, and on how to address this emotional dimension in the way we classify and access movies, by exploring and evaluating the design of iFelt in its different ways to classify, access, browse and visualize movies based on their emotional impact. 相似文献
135.
Youri Plokhenko W. Paul Menzel Henry E. Revercomb Eva Borbas Paolo Antonelli EliSabeth Weisz 《International journal of remote sensing》2013,34(7):2105-2125
An approach using spatial analysis of satellite IR spectral measurements for quality assessment is presented. The second spatial differential is used as a model of measurement noise for spatially smooth radiative fields. Spatial differentiation significantly magnifies the noise contribution and reduces the physical signal amplitude because of differences in spatial distributions of instrument noise and atmospheric thermal fields. The second spatial differential represents a convenient and effective tool for numerical analysis of satellite IR measurements. This paper demonstrates that statistics of the second spatial differential are informative predictors for data‐quality characterization. Statistics of the second spatial differential are used for identifying anomalies in spectral channel data caused by detector noise, sensitivity loss to spatial shortwave thermal variations, and spatially (temporally) correlated noise. 相似文献
136.
The effects of salt-curing and salting procedures on the microstructure of cod (Gadus morhua) muscle
Kristin Anna Thorarinsdottir Sigurjon Arason Sjofn Sigurgisladottir Valur N. Gunnlaugsson Jonina Johannsdottir Eva Tornberg 《Food chemistry》2011
The aim of this study was to investigate the effects of salting and different pre-salting procedures (injection and brining versus brining only) on the microstructure and water retention of heavy salted cod products. Salting resulted in shrinkage of fibre diameter and enlargement of inter-cellular space. Water was expelled from the muscle and a higher fraction became located in the extra-cellular matrix. These changes were suggested to originate from myofibrillar protein aggregation and enzymatic degradation of the connective tissue. During rehydration, the muscle absorbed water again and the fibers swelled up to a similar cross-sectional area as in the raw muscle. However, the inter-cellular space remained larger, resulting in a higher water content of the muscle in the rehydrated stage. The effects of different salting procedures were strongest after salting. At that stage of the process, the inter-cellular space tended to be larger in the injected and brined muscle than in the brined only. 相似文献
137.
This study compares the citations characteristics of researchers in engineering disciplines with other major scientific disciplines,
and investigates variations in citing patterns within subdisciplines in the field of engineering. Utilizing citations statistics
including Hirsch’s (Proc Natl Acad Sci USA 102(46):16569–16572, 2005) h-index value, we find that significant differences in citing characteristics exist between engineering disciplines and
other scientific fields. Our findings also reveal statistical differences in citing characteristics between subdisciplines
found within the same engineering discipline. 相似文献
138.
Ivan Ostrovský Eva Pavlíková Jaroslav Blaško Renáta Górová Róbert Kubinec Milan Margetín Ladislav Soják 《International Dairy Journal》2009,19(9):545-549
The profile variations of approximately 70 fatty acids (FAs) in milk of ewes consuming total mixed rations (TMR) and grazing natural pasture were determined. Milk of ewes grazing pasture in May and September in the Slovak Republic contained 3-times more conjugated linoleic acid (CLA) (P < 0.001) and trans-vaccenic acid (TVA) (P < 0.001), and 2-times more α-linolenic acid (ALA) (P < 0.001) than that of ewes fed TMR. A doubling of the CLA and TVA contents of milk of ewes fed with TMR was achieved by changing to meadow hay containing a higher ALA content. Less availability of vegetation and lower ALA pasture content in summer (P < 0.001) caused a 2-fold decrease (P < 0.001) of CLA and TVA contents when compared with data obtained in May. With grass re-growth and an increase in pasture ALA content in September, the CLA and TVA contents rose to values similar to those obtained in May (P > 0.05). No significant differences in the FA composition in milk of ewes grazing on summer pasture at higher altitude were observed. 相似文献
139.
Currently the Journal Impact Factors (JIF) attracts considerable attention as components in the evaluation of the quality
of research in and between institutions. This paper reports on a questionnaire study of the publishing behaviour and researchers
preferences for seeking new knowledge information and the possible influence of JIF on these variables. 54 Danish medical
researchers active in the field of Diabetes research took part. We asked the researchers to prioritise a series of scientific
journals with respect to which journals they prefer for publishing research and gaining new knowledge. In addition we requested
the researchers to indicate whether or not the JIF of the prioritised journals has had any influence on these decisions. Furthermore
we explored the perception of the researchers as to what degree the JIF could be considered a reliable, stable or objective
measure for determining the scientific quality of journals. Moreover we asked the researchers to judge the applicability of
JIF as a measure for doing research evaluations. One remarkable result is that app. 80% of the researchers share the opinion
that JIF does indeed have an influence on which journals they would prefer for publishing. As such we found a statistically
significant correlation between how the researchers ranked the journals and the JIF of the ranked journals. Another notable
result is that no significant correlation exists between journals where the researchers actually have published papers and
journals in which they would prefer to publish in the future measured by JIF. This could be taken as an indicator for the
actual motivational influence on the publication behaviour of the researchers. That is, the impact factor actually works in
our case. It seems that the researchers find it fair and reliable to use the Journal Impact Factor for research evaluation
purposes. 相似文献
140.
立面、周边环境以及对所在街区的一系列回应,是玛丽蒂姆酒店的设计要点。这个占地约1.2万m2的酒店基地紧邻文化中心(Kulturforum)和著名的文物保护建筑贝壳屋(Shellhaus,建筑师:Emil Fahrenkamp),且距国家美术馆和波茨坦广场不远。 相似文献