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11.
Zellini (1979, Theorem 3.1) has shown how to decompose an arbitrary symmetric matrix of ordern ×n as a linear combination of 1/2n(n+1) fixed rank one matrices, thus constructing an explicit tensor basis for the set of symmetricn ×n matrices. Zellini's decomposition is based on properties of persymmetric matrices. In the present paper, a simplified tensor basis is given, by showing that a symmetric matrix can also be decomposed in terms of 1/2n(n+1) fixed binary matrices of rank one. The decomposition implies that ann ×n ×p array consisting ofp symmetricn ×n slabs has maximal rank 1/2n(n+1). Likewise, an unconstrained INDSCAL (symmetric CANDECOMP/PARAFAC) decomposition of such an array will yield a perfect fit in 1/2n(n+1) dimensions. When the fitting only pertains to the off-diagonal elements of the symmetric matrices, as is the case in a version of PARAFAC where communalities are involved, the maximal number of dimensions can be further reduced to 1/2n(n–1). However, when the saliences in INDSCAL are constrained to be nonnegative, the tensor basis result does not apply. In fact, it is shown that in this case the number of dimensions needed can be as large asp, the number of matrices analyzed.  相似文献   
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In the present research, we investigated the modification of the strength of the Poggendortf illusion as a function of different densities ofrandom dot textures failing the space between the verticals. The results ofExperiment 1 show that the illusory effect is a nonlinear function ofthe texture parameterr, the ratio of black pixels to white and black pixels, with a minimum forr=0.5, approximately, and a maximum forr=0 andr=1. The results may be interpreted by an analytical model of perceptual space dynamics, in which the effect dependson the amount of interaction between points of different light intensity. A computer simulation performed by applying the analytical model to different values ofr shows a good agreement between the predictions and the experimental data. To test the hypothesis underlying the model, a second experiment was carried out to measure the magnitude of the expansion ofthe space between the verticals as a function of the parameterr. The results are consistent with the hypothesis of the model. The overall data are discussed in terms of their implications on various theories proposed for the Poggeadorff illusion.  相似文献   
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Quantum MV algebras   总被引:1,自引:0,他引:1  
We introduce the notion of quantum MV algebra (QMV algebra) as a generalization of MV algebras and we show that the class of all effects of any Hilbert space gives rise to an example of such a structure. We investigate some properties of QMV algebras and we prove that QMV algebras represent non-idempotent extensions of orthomodular lattices.I should like to thank Prof. M.L. Dalla Chiara and Dr. P. Minari for many interesting comments and remarks. Daniele Mundici  相似文献   
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Medicine is arriving at a new millenium. One of its most urgent tasks is to reconcile social health demands with a renewed medical paradigm capable of including them. This challenge requires a reexamination of the definition of medicine. This work takes up the original greek definition of medicine (Tekhne Iatrike) and the Medical Act according to P. Lain Entrago, and analyzes Heidegger's interpretation of Tekhne. It points out the two main ways in which current medical practice is sustained: the Instrumental Medical Act (IMA), which organizes medical production, and the Productive Medical Act (PMA), which motivates it. An overwhelmed Medical Act, fighting but incapable of optimizing an insufficient medical production, is observed. This medical act is searching for foundations: an hegemonic IMA, associated disciplines and a new medical hierarchy.  相似文献   
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In four studies, we investigated the role of remembering, reflecting on, and mutating personal past moral transgressions to learn from those moral mistakes and to form intentions for moral improvement. Participants reported having ruminated on their past wrongdoings, particularly their more severe transgressions, and they reported having frequently thought about morally better ways in which they could have acted instead (i.e., morally upward counterfactuals; Studies 1–3). The more that participants reported having mentally simulated morally better ways in which they could have acted, the stronger their intentions were to improve in the future (Studies 2 and 3). Implementing an experimental manipulation, we then found that making accessible a morally upward counterfactual after committing a moral transgression strengthened reported intentions for moral improvement—relative to resimulating the remembered event and considering morally worse ways in which they could have acted instead (Study 4). We discuss the implications of these results for competing theoretical views on the relationship between memory and morality and for functional theories of counterfactual thinking.  相似文献   
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The goal of this study was to assess the effect of intercessory prayer in the psychological, spiritual and biological scores of breast cancer patients who are undergoing radiotherapy. Double-blind RCT comprising a sample of 31 participants (15 in the Control Group and 16 in the Intervention Group). Data collection was performed in three time points (T0, T1 and T2). Significant changes have been identified in the intra-group analysis, concerning the decrease in spiritual distress score; negative religious/spiritual coping prevailed, while the total religious/spiritual coping increased between the posttest T2 to T0. Intercessory prayer was effective in religious and spiritual scores.

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