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51.
In this paper, we propose a numerically robust blind equalization scheme to mitigate cochannel and intersymbol interferences and separate signals from a convolutive mixture in multiple-input multiple-output (MIMO) communication systems. The robustness of the proposed scheme is achieved through a particular dual-mode operation applied to a constant-modulus-based space-time algorithm that corrects phase rotations. In the first mode of operation, the consistency in the nonlinear estimates of the transmitted signals is ensured. In the second mode, the Euclidean norms of the equalizer coefficient vectors decrease along the iterations, which allows the algorithm to return to the first mode of operation, where the estimation of the transmitted signals really occurs. In particular, we apply this scheme to a multimodulus version of the multiuser Shalvi-Weinstein algorithm (MU-SWA). By means of a deterministic stability analysis assuming the persistence of excitation condition, we show that the dual-mode MU-SWA does not diverge.  相似文献   
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This study evaluated the effect of a multi-component intervention on motor performance (MP) and metabolic risk markers (MRM) in overweight/obese youth. A secondary aim was to examine whether changes in MP are associated to changes in MRM. A 3-month multi-component intervention was performed, consisting of physical exercise sessions (twice/week;1h), nutritional education sessions (once/month), and parental support (twice/week). The sample included 35 volunteers (7–13 y.o), allocated to intervention (INT, n = 17) and control (CONT, n = 18) group. Variables were measured pre (T0) and post intervention (T1). Fasting blood samples were analyzed for MRM. MP tests included the measurement of health related physical fitness components and motor coordination performance (KTK battery). To assess food intake, a 24-hour recall diary was used. GLM-ANCOVA was performed. Standardized scores were calculated for the outcome variables, and multilinear regressions were applied to analyze associations between the key variables. INT group showed improvements in MP, glycolytic and hepatic profiles. After adjustments for MVPA, SB, total intake and maturational stage, negative associations between %ΔMP and %Δglycolytic (β = -.424; 95%CI:-0.343:-0.022), and %Δhepatic scores (β = -.382 95%CI:-0.001:-0.009) were observed. The intervention produced a moderate-to-high effect on the MP and some MRM. Changes in MP were inversely associated with changes in glycolytic and hepatic markers.  相似文献   
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Recognition memory in Down's syndrome and normal infants   总被引:2,自引:0,他引:2  
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Objective. The aims of this article were to test the measurement invariance of the Italian and American versions of the Adult Parental Acceptance–Rejection Questionnaire and to compare adults’ remembrances of parental acceptance–rejection across the two nations. Design. The Adult Parental Acceptance–Rejection Questionnaire was administered to 564 Italian adults (M = 23.04 years) and 509 U.S. American adults (M = 22.09 years), matched by gender and age. The measurement invariance of the Parental Acceptance–Rejection Questionnaire was first established by means of multi-group confirmatory factor analyses. Results. The Parental Acceptance–Rejection Questionnaire is fully invariant across the two cultures, and adults organize their remembrances of mothers’ and fathers’ parenting around the same four classes of behavior in both nations. Italian and American adults tend to remember their parents as having been quite loving, with Italian parents being remembered as slightly less warm and more hostile than American parents. Conclusions. The full invariance of the Parental Acceptance–Rejection Questionnaire across the two populations represents additional strong evidence for the universality of interpersonal acceptance–rejection theory. Measurement invariance also confirmed that the Adult Parental Acceptance–Rejection Questionnaire (short form) can be used to measure adult remembrances of parental acceptance–rejection across these two populations.  相似文献   
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Review papers tend to be cited more frequently than regular research articles. This fact, together with the continuous increase of the share of reviews in scientific literature, can have important consequences for the measurement of individuals’ research output, usually based on citation analysis. However, studies evaluating the differences in citations of review papers compared to original research articles are almost non-existing in the literature. This paper presents a thorough analysis of the overcitation and overrepresentation of review papers in the most cited papers of the 35 largest subject categories in Science Citation Index-Expanded. Results indicate the average citations received by reviews depends largely on the research area considered, varying from 1.34 to 6.74 times the citations received by original research articles (average value is 2.95). Correlated with this overcitation, there is an important overrepresentation of reviews in the most cited papers, this overrepresentation being greater when the most highly cited papers are considered, i.e. 0.05% and 0.1% most cited papers, where the share of reviews have increased from 16 to 18% in 1990 to around 40% in 2010. Interestingly, the overcitation and overrepresentation in the most cited papers is more important in the areas with the lowest shares of reviews in total publications.  相似文献   
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The current study examined the prevalence of ethnic incongruence in three school psychological services: assessment, consultation, and counseling; the prevalence of diversity training among school psychologists; and practitioners' attitudes about their training experiences. A mail survey was sent to a random sample of 500 school psychologists drawn from the 1999 membership roster of the National Association of School Psychologists (NASP). Ethnic incongruence, defined as ethnic differences between a professional and a client, was commonly reported for assessment, consultation, and counseling cases. Diversity training was reported by 90.7% of participating school psychologists in the form of graduate coursework, internship experiences, or continuing education. Though most respondents rated their training experiences positively, improvements were suggested. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 419–432, 2005.  相似文献   
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