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In this note, simple symmetric interval bounds on the singular values of a matrix based on its Gershgorin disks are proposed. This allows the Gershgorin theorem to be used not only to provide information about the location of the eigenvalues of a matrix but also its singular values. This is utilized for the proposition of a new design technique for singular value loop shaping based on the diagonal dominance methodology for design of linear multivariable plants. In return, this allows multiple-channel simply structured controllers to be designed with a view to robustness and to meet constraints and specifications on the behavior of its singular values. A design example is given demonstrating the effectiveness of this approach.  相似文献   
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The ACTS program is moving the results of the R&D of the parent RACE program nearer to realization through technology and user trials. Particularly in the mobile domain of ACTS, several projects have been investigating the user dimension in the context of the third-generation Universal Mobile Telecommunications Service. Results so far suggest many opportunities to broaden participation, exploit the inherent benefits of the mobile environment, and take advantage of the enormous improvements in wireless communications to realize the potential of global multimedia mobility. This article considers the needs of users for mobile multimedia applications and the consequences of those needs on the equipment, supporting services and teleservices, and communications bearers  相似文献   
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Qualitative performance features and extended-time effects on the Block Design subtest of the Wechsler Adult Intelligence Scale—Revised (WAIS—R) were examined in 145 healthy Ss (aged 50–95 yrs). Raw scores were calculated at standard and extended time limits; error types and starting points were recorded for a subgroup of Ss. In Ss age 60 yrs and older, there was a consistent decline with age in overall scores at both time limits. Extra time allotments resulted in modest but significant increases in scores. Older and younger Ss benefited equally from the extra time, indicating that the age-related decline on this task cannot be accounted for by general age-related psychomotor slowing. Single- and multiblock rotation errors were relatively common, whereas stimulus boundedness and broken configurations were rare. Despite some potential limitations in generalizability, the results suggest that the incorporation of qualitative scoring procedures in the assessment of visuoconstructional skills may enhance understanding of normal and abnormal brain–behavior relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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O'Meara GM  Munro PA 《Meat science》1985,12(2):91-103
The enzymic hydrolysis and solubilisation of the three meat protein fractions have been investigated in order to elucidate some aspects of the hydrolysis of whole beef protein. Much of the water-soluble sarcoplasmic protein fraction was insolubilised on heating for 25 min at 60°C. While most of this insoluble protein was easily resolubilised enzymically, some of it remained insoluble after 5 hours' hydrolysis. Solubilisation of connective tissue by Alcalase after a 3 h reaction increased markedly from 23% at 55°C to 99% at 60°C. This explains the high optimum temperature for solubilisation of whole beef by Alcalase. A significant portion of myofibrillar tissue remained insoluble after 3 hours' reaction. indicating that the majority of the insoluble solids remaining after whole meat hydrolysis at 60°C derived from myofibrillar tissue. There was good agreement between an experimental reaction progress curve for whole beef hydrolysis and one estimated from progress curves for hydrolysis of the three meat protein fractions.  相似文献   
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Amnestic mild cognitive impairment (aMCI) often is an early stage of Alzheimer's disease (AD). MCI is characterized by cognitive decline departing from normal cognitive aging but that does not significantly interfere with daily activities. This study explores the potential of scalp EEG for early detection of alterations from cognitively normal status of older adults signifying MCI and AD. Resting 32-channel EEG records from 48 age-matched participants (mean age 75.7 years)—15 normal controls (NC), 16 early MCI, and 17 early stage AD—are examined. Regional spectral and complexity features are computed and used in a support vector machine model to discriminate between groups. Analyses based on three-way classifications demonstrate overall discrimination accuracies of 83.3%, 85.4%, and 79.2% for resting eyes open, counting eyes closed, and resting eyes closed protocols, respectively. These results demonstrate the great promise for scalp EEG spectral and complexity features as noninvasive biomarkers for detection of MCI and early AD.  相似文献   
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We propose a uniform method to encode various types of trees succinctly. These families include ordered (ordinal), k-ary (cardinal), and unordered (free) trees. We will show the approach is intrinsically suitable for obtaining entropy-based encodings of trees (such as the degree-distribution entropy). Previously-existing succinct encodings of trees use ad hoc techniques to encode each particular family of trees. Additionally, the succinct encodings obtained using the uniform approach improve upon the existing succinct encodings of each family of trees; in the case of ordered trees, it simplifies the encoding while supporting the full set of navigational operations. It also simplifies the implementation of many supported operations. The approach applied to k-ary trees yields a succinct encoding that supports both cardinal-type operations (e.g. determining the child label i) as well as the full set of ordinal-type operations (e.g. reporting the number of siblings to the left of a node). Previous work on succinct encodings of k-ary trees does not support both types of operations simultaneously (Benoit et al. in Algorithmica 43(4):275–292, 2005; Raman et al. in ACM-SIAM Symposium on Discrete Algorithms (SODA), pp. 233–242, 2002). For unordered trees, the approach achieves the first succinct encoding. The approach is based on two recursive decompositions of trees into subtrees. Recursive decomposition of a structure into substructures is a common technique in succinct encodings and has even been used to encode (ordered) trees (Geary et al. in ACM Trans. Algorithms 2(4):510–534, 2006; He et al. in ICALP, pp. 509–520, 2007) and dynamic binary trees (Munro et al. in ACM-SIAM Symposium on Discrete Algorithms (SODA), pp. 529–536, 2001; Storm in Representing dynamic binary trees succinctly, Master’s thesis, 2000). The main distinction of the approach in this paper is that a tree is decomposed into subtrees in a manner that the subtrees are maximally isolated from each other. This intermediate decomposition result is interesting in its own right and has proved useful in other applications (Farzan et al. in ICALP (1), pp. 451–462, 2009; Farzan and Munro in ICALP (1), pp. 439–450, 2009; Farzan and Kamali in ICALP, 2011).  相似文献   
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