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1.
One major problem with purchasing through the Web is locating reliable suppliers that offer the exact product or service you need. In the usual approach, you access an indexing based search engine, specify keywords for the purchase, and initiate the search. The outcome is typically a list ranked according to keyword matches; useful, but not always helpful. Keyword matches provide only one ingredient to finding the right Web sites. The ranking should also consider the satisfaction of previous customers purchasing from those sites, customer profiles, and customer behavior. The Obelix search engine uses reconfigurable technology to apply customer satisfaction data obtained from the Internet service provider infrastructure to refine its search criteria. The Obelix system collects data about customer activities, calculates a customer satisfaction index, and updates the search engines with its findings  相似文献   
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Visualizing multidimensional data such as the mel frequency cepstral coefficients (MFCCs) proves difficult, especially when the number of dimensions is greater than 3. As a result, it becomes extremely difficult to spot trends in high-dimensional signal interactions. Andrews curves seam to aid in the process of performing graphical analysis of high-dimensional data. This study examines the properties of the babble in the feature domain as well as the effect of the babble noise on the MFCCs of clean speech. Experiments have been conducted using two babble models: the overlapping conversation model and the overlapping speaker model. The purpose of this paper was to provide an insight into the effect of the babble noise on the first thirteen MFCCs of clean speech through the use of Andrews curves. The investigations of this paper give a visual comparison of the signals to expose trends, which the conventional visualization methods do not. The use of Andrews curves not only allows the signal to be observed, but also allows for a statistical comparisons between signals. With a better understanding of the difference between the models, it would be possible to develop systems, which are more robust in babble-corrupted environment.  相似文献   
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A systematic approach towards accident analysis and prevention has been developed. It relies on system theory as an incident causation model, and adopts a hybrid model for identifying elements of the safety management system. PDCA (Plan-Do-Check-Act) process, commonly practiced in business for quality control, has been applied to defining components of the system. Using the experts’ judgment, accident data and their reported causes are correlated to the defined components, with RBI (risk-based inspection) defined consequence scores as weighting factors. The application of this approach allows users such as governments and companies to identify and prioritize among causes of accidents and near-misses in the petrochemical industry. A case study using the accident data of Yeosu petrochemical complex from 1990 to 2004 has been applied to illustrate insights readily obtainable by using the developed analysis technique. The results suggest comprehensive identification and ranking of accident causes for effective prevention of accidents in the future.  相似文献   
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Previous studies have demonstrated that, when they are emotional, individuals are more likely to attend to emotional stimuli. However, such work has not established that individuals attend to the emotional dimensions of complex stimuli or that such changes in focus of attention affect judgments. In the present experiments a multidimensional scaling analysis was used to assess the weights that happy, sad, and neutral-emotion participants gave to emotional and nonemotional dimensions of face stimuli in judgments of similarity. Compared to neutral-emotion participants, those in emotional states gave more weight to the emotional dimension of the faces, less weight to other face dimensions, and rated pairs of faces that expressed the same emotion as more similar. Emotion-congruent dimension use was also observed in one experiment. Results are discussed with respect to emotional response categories (P. M. Niedenthal & J. B. Halberstadt, 1995), the tendency for stimuli to cohere as categories on the basis of the emotional response they elicit in the perceiver. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Cortical vein thrombosis without sinus involvement is rarely diagnosed, although it may commonly be overlooked. We report four cases of cerebral venous thrombosis limited to the cortical veins. The diagnosis was made on surgical intervention in one patient and by angiography in three patients. Together with a survey of the published cases, the clinical and neuroimaging patterns of our patients allow delineation of several features suggestive of cortical venous stroke. Focal or generalized seizures followed by hemiparesis, aphasia, hemianopia, or other focal neurologic dysfunction in the absence of signs of increased intracranial pressure should suggest this possibility. Neuroimaging (CT, MRI) shows an ischemic lesion that does not follow the boundary of arterial territories and often has a hemorrhagic component, without signs of venous sinus thrombosis. Conventional angiography demonstrates no arterial occlusion but may show cortical vein thrombosis corresponding to the infarct, although these may also be nonspecific findings. The role of MR angiography, which is well-established in sinus thrombosis, remains to be assessed in patients with brain ischemia due to isolated cortical vein occlusion.  相似文献   
7.
B cells expressing CD5 also carry its ligand, CD72. As an approach to understanding the role of CD5 and CD72 on B cells, we have examined the association of CD72 with CD5 and slgM by modulation/co-modulation and capping/co-capping following ligation of these surface molecules with specific antibodies. Modulation and co-modulation were measured after 24 h, whilst capping was measured after 1 h. CD5 and slgM co-modulated each other, CD72 co-modulated with slgM and CD5, but anti-CD72 did not affect either slgM or CD5. CD5 and slgM co-capped each other, whilst CD72 failed to co-cap with either slgM or CD5. The CD5-induced co-modulation of CD72 was partially blocked by specific protein tyrosine kinase inhibitor, but not the slgM-induced co-modulation, Protein kinase C (PKC) inhibitors abrogated the anti-mu- but not the anti-CD5-triggered modulation of CD72, whereas PKC activators prevented the CD5- but not the slgM-induced 24 h modulation of CD72. None of these drugs was able to modify the anti-CD72-induced modulation of CD72. Our data suggest that CD5 is physically associated with slgM in the B cell receptor complex but not with CD72. Furthermore, from the effect of drugs on modulation, there appears to be different associations of CD72 with slgM and CD5. These two pathways differed in some respects, consistent with a co-stimulatory function of CD72 and CD5 in B cell activation.  相似文献   
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A generalized Helmholtz condition for field uniformity is derived from the closed form solution of the magnetic field in a multilayer rectangular coil pair as a function of coil dimensions and pair separation. The relation among the dimensions satisfying this condition is found and plotted in parametric form for single layer coils and for a multilayer coil with a specific winding thickness. For square coils of cross section small compared to their mean radius, the gap separation approaches half the coil radius, analogous to the classical condition for circular coils. Comparison between theoretical and measured values for tolerances within +/-5% of the field at the system center agree within a 6% maximum deviation. For the experimental coil, the area enclosed by the +/-5% contour was 58% of the area of the full coil.  相似文献   
10.
Yeom D  Kang J  Lee M  Jang J  Yun J  Jeong DY  Yoon C  Koo J  Kim S 《Nanotechnology》2008,19(39):395204
The memory characteristics of ZnO nanowire-based nano-floating gate memory (NFGM) with Pt nanocrystals acting as the floating gate nodes were investigated in this work. Pt nanocrystals were embedded between Al(2)O(3) tunneling and control oxide layers deposited on ZnO nanowire channels. For a representative ZnO nanowire-based NFGM with embedded Pt nanocrystals, a threshold voltage shift of 3.8?V was observed in its drain current versus gate voltage (I(DS)-V(GS)) measurements for a double sweep of the gate voltage, revealing that the deep effective potential wells built into the nanocrystals provide our NFGM with a large charge storage capacity. Details of the charge storage effect observed in this memory device are discussed in this paper.  相似文献   
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