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991.
Caprara Gian Vittorio; Barbaranelli Claudio; Consiglio Chiara; Picconi Laura; Zimbardo Philip G. 《Canadian Metallurgical Quarterly》2003,84(4):849
A rare collection of personality assessments from 103 Italian politicians revealed predictable patterns of contrasts and similarities with personality dimensions from a large normative sample (N = 4,578). Three modal personality characteristics distinguished politicians, with their significantly higher levels of Energy, Agreeableness, and Social Desirability, from the general public. Comparability between politicians and the public existed on dimensions of Emotional Stability, Conscientiousness, and Openness (Big Five Questionnaire assessment). Politicians from rival coalitions differed on several dimensions; center-right was higher than center-left in Energy and Conscientiousness. Congruencies emerged between politicians and voters for their coalition on all personality dimensions, except that center-left politicians were higher in Energy than center-left voters, and center-right politicians were higher than voters in both Energy and Agreeableness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Terranova Maria Livia; Laviola Giovanni; de Acetis Luigi; Alleva Enrico 《Canadian Metallurgical Quarterly》1998,112(1):3
The development of agonistic behavior was characterized in outbred Swiss CD-1 male Mus domesticus. At weaning (postnatal day [PND] 21), mice were housed either individually or as male pairs. Social encounters were carried out between dyads of initially unfamiliar same-age and same-housing subjects every 3rd day, from PND 23 to 47. The majority of both offensive and defensive elements had their onset around PND 29. Overall, their expression increased around puberty (i.e., on PND 35), which also represented the peak of an inverted U-shaped profile for the frequency of the "ambivalent" tail rattling behavior. A stability of dominance–submission relationships over development appeared, and early short latencies to display either the first crouched posture (subordinate) or the first attack (dominant) turned out to be possible predictors of adult social status. Ongoing individual housing was associated with a greater expression and an earlier onset of fighting behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Marco Cadoli Luigi Palopoli Francesco Scarcello 《Annals of Mathematics and Artificial Intelligence》1999,27(1-4):129-148
Propositional greatest lower bounds (GLBs) are logically‐defined approximations of a knowledge base. They were defined in the context of Knowledge Compilation, a technique developed for addressing high computational cost of logical inference. A GLB allows for polynomial‐time complete on‐line reasoning, although soundness is not guaranteed. In this paper we propose new algorithms for the generation of a GLB. Furthermore, we give precise characterization of the computational complexity of the problem of generating such lower bounds, thus addressing in a formal way the question “how many queries are needed to amortize the overhead of compilation?” 相似文献
994.
Close relationship partners often share successes and triumphs with one another, but this experience is rarely the focus of empirical study. In this study, 79 dating couples completed measures of relationship well-being and then participated in videotaped interactions in which they took turns discussing recent positive and negative events. Disclosers rated how understood, validated, and cared for they felt in each discussion, and outside observers coded responders' behavior. Both self-report data and observational codes showed that 2 months later, responses to positive event discussions were more closely related to relationship well-being and break-up than were responses to negative event discussions. The results are discussed in terms of the recurrent, but often overlooked, role that positive emotional exchanges play in building relationship resources. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
On the information throughput and optimized power allocation for MIMO wireless systems with imperfect channel estimation 总被引:1,自引:0,他引:1
In this paper, we focus on the throughput analysis, outage evaluation and optimized power allocation for Multiple-Input Multiple-Output (MIMO) pilot-based wireless systems subject to short-term constraints on the radiated power and equipped with a feedback-path for communicating back to the transmitter the imperfect MIMO channel estimates available at the receiver. The case of the ergodic throughput for Gaussian distributed input signals is analyzed, and the conditions for the (asymptotical) achievement of the Shannon capacity are pointed out. The main contributions of this work may be so summarized. First, we develop closed-form analytical expressions for the computation of the ergodic information throughput conveyed by the considered MIMO system for the case of ideal feedback link. Second, we present an iterative algorithm for the optimized power allocation over the transmit antennas that explicitly accounts for the imperfect MIMO channel estimates available at the receiver. Third, after relaxing the assumption of ideal feedback link, we test the sensitivity of the proposed power allocation algorithm on errors possibly introduced by the feedback channel, and then, we numerically evaluate the resulting throughput loss. Finally, we develop closed-form upper and lower bounds on the outage probability that are asymptotically tight. 相似文献
996.
Luigi Pistoni Massimiliano Merisio 《电子与电脑》2006,(8):86-90
为提高能效和电池利用率,缩减设备尺寸,意法半导体(ST)针对便携设备新开发出一个完全单片的降压升压转换器。本文详细介绍了新产品的主要特性与性能,重点讲解降压到升压软转换和自动转换的创新体系结构,并于文末列举了几个应用创意。 相似文献
997.
Anna Tonazzini Luigi Bedini Emanuele Salerno 《IEEE transactions on image processing》2006,15(2):473-482
This paper deals with blind separation of images from noisy linear mixtures with unknown coefficients, formulated as a Bayesian estimation problem. This is a flexible framework, where any kind of prior knowledge about the source images and the mixing matrix can be accounted for. In particular, we describe local correlation within the individual images through the use of Markov random field (MRF) image models. These are naturally suited to express the joint pdf of the sources in a factorized form, so that the statistical independence requirements of most independent component analysis approaches to blind source separation are retained. Our model also includes edge variables to preserve intensity discontinuities. MRF models have been proved to be very efficient in many visual reconstruction problems, such as blind image restoration, and allow separation and edge detection to be performed simultaneously. We propose an expectation-maximization algorithm with the mean field approximation to derive a procedure for estimating the mixing matrix, the sources, and their edge maps. We tested this procedure on both synthetic and real images, in the fully blind case (i.e., no prior information on mixing is exploited) and found that a source model accounting for local autocorrelation is able to increase robustness against noise, even space variant. Furthermore, when the model closely fits the source characteristics, independence is no longer a strict requirement, and cross-correlated sources can be separated, as well. 相似文献
998.
Fernanda Andreola Maria Cristina D'Arrigo Cristina Leonelli Cristina Siligardi Gian Carlo Pellacani 《Journal of the American Ceramic Society》2003,86(5):864-866
In the present work thermal and chemical properties of a glass-ceramic frit containing zirconium oxide are evaluated after milling in various polar and nonpolar solvents. Particle-size distribution is one of the main variables investigated to evaluate the efficiency of several solvents. Milling in various solvents does not affect the thermal properties of the glass while the presence of polar groups in the solvent molecule increases the cation release from the glass. 相似文献
999.
After an earthquake, which struck the Eastern part of Sicily in 1990, some structural elements of the Church of S. Nicolò l'Arena in Catania, as the dome and the vaults, were damaged; vertical cracks on the two pillars were detected. It is not clear whether those cracks were already visible and were simply propagating during the earthquake. It is known that the two pillars probably belong to the original construction of the church.An investigation programme (including historical research and experimental investigation with sonic, radar, flat-jack, coring, boroscopy, etc.) has been recently planned to design the preservation and restoration actions.The results obtained from sonic tests were compared to the results of the other type of tests in order to set up an investigation procedure useful for these cases. The paper presents and discusses the preliminary results of the research carried out by the authors. 相似文献
1000.