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11.
Oversampled Gabor representation for transient signals   总被引:2,自引:0,他引:2  
Considers the Gabor representation that uses a one-sided exponential window for detection and analysis of transient signals. Earlier results on the critically sampled case are extended to the more practically useful oversampled case. For oversampling by an integer factor, the authors derive an explicit analytical expression for the dual window (dual frame) function required for computing the Gabor representation. Based on this expression they develop an efficient procedure for computing the Gabor coefficients. Finally, they demonstrate the performance of the method by numerical examples  相似文献   
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The pressure-flow (P-F) relationship in intravenous catheters is shown to be represented by the predictive model P = RLF + RTF2. The pressure loss due to F, calculated from experimental data, was found to equal the expected Poiseuille laminar flow loss. Pressure loss due to F2 was found to be the sum of turbulent P losses due to entrance length flow disturbance, kinetic energy at the outflow, and minor shape change losses. Analysis of the flow capabilities of intravenous catheters can be used to evaluate suitability for specific intravenous infusion needs.  相似文献   
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Although it rejects self-awareness as psychological bedrock, behavior-analytic theory can be stated self-inclusively, keeping the theorist within view. Its principles of discrimination and generalization have been elaborated to include concepts and higher order conditionalities, including those of logic and of awareness. Its violating a cultural bias that is called the "fundamental attribution error" may be a primary source of controversies. Its other disagreements with mainstream psychologies hinge more on contiguous vs remote causation than on mentalism vs antimentalism, which Skinner emphasized. The nonmediational, Skinnerian theorist is a participation in the world rather than an isolated self. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Continuous surface boundaries, object shape, and global motion can be perceived from information that is fragmentary in both space and time. The authors report investigations indicating that accretion and deletion of texture is only 1 member of a broader class of element transformations that produce boundaries, shape, and motion, through spatiotemporal boundary formation (SBF). Four experiments exploring SBF are reported. The 1st 3 examine the class of transformations producing SBF, indicating that local element changes in color, orientation, or location are all effective. A 4th experiment examines temporal constraints on SBF. Integration of local element changes to produce boundaries, form, and global motion appears to be confined to a 165-msec window. Two classes of spatiotemporal integration models are considered; the relation between SBF and other cases of boundary interpolation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Political economists agree that a trade-off exists between equality and efficiency. Using a hypothetical society paradigm, the mean income (representing efficiency) and income variability (representing equality) of distributions of wealth and the correlation between wealth and effort within a society were manipulated. Ss made all pairwise comparisons of distributions within societies of differing meritocracy. A "maximin" principle best described trade-off resolution strategies when effort and outcome were weakly linked: People maximized the minimum standard of living within a society. A compromise principle best described preferences when income was tightly linked to effort: People rejected distributions in which some citizens fell below the "poverty line" but maximized efficiency above this constraint. Ideological polarization was pronounced under moderate meritocracy; here liberals could focus on the role of chance and conservatives on the role of effort and ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Electron-impact excitation cross sections are presented for the dipole- and spin allowed transitions from the ground states to the np 2P states for hydrogen and lithium, and to the 1snp 1P states for helium, n = 2 through 10. Two scaling formulas developed earlier by Kim [Phys. Rev. A 64, 032713 (2001)] for plane-wave Born cross sections are used. The scaled Born cross sections are in excellent agreement with available theoretical and experimental data.  相似文献   
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Examined intake profiles of 54 depressed women survivors of child sexual abuse presenting for a specialized group therapy program at a community mental health center. The 32 therapy completers were compared with the 22 dropouts. Both groups possessed extensive and severe childhood and adult abuse histories. Both were extremely socially disadvantaged and clinically impaired as measured on the Millon Clinical Multiaxial Inventory (MCMI). Dropouts were more likely to have been battered as children and to have been sexually abused only within the family. Completers were more likely to have been multiply offended both by intrafamilial and extrafamilial perpetrators. The groups differed in terms of marital status and extent of economic dependence on spouse. Dropouts appeared to be more actively enmeshed in the abuse cycle at the time of therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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