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排序方式: 共有1303条查询结果,搜索用时 234 毫秒
61.
Holden Ronald R.; Wasylkiw Louise; Starzyk Katherine B.; Book Angela S.; Edwards Melanie J. 《Canadian Metallurgical Quarterly》2006,38(1):24
Four studies investigated the dimensionality of the NEO Five-Factor Inventory (NEO-FFI; P. T. Costa & R. R. McCrae, 1992). In Study 1, four inferential dimensions and four clusters represented the NEO-FFI when 114 undergraduates freely sorted items into categories. Construct validity for four item-clusters derived from the inferential space was obtained in Study 2 based on self-report with 304 undergraduates. Study 3 validated these inferential clusters using self and peer reports for 420 undergraduates. Study 4 validated the cluster scales for predicting quality of life and significant social and cultural behaviours for 110 undergraduates. Implications for implicit personality theory, the number of dimensions issue in personality, and test construction are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Katherine Donaldson Gregory K. Myers 《International Journal on Document Analysis and Recognition》2005,7(2-3):159-167
To increase the range of sizes of video scene text recognizable by optical character recognition (OCR), we developed a Bayesian super-resolution algorithm that uses a text-specific bimodal prior. We evaluated the effectiveness of the bimodal prior, compared and in conjunction with a piecewise smoothness prior, visually and by measuring the accuracy of the OCR results on the variously super-resolved images. The bimodal prior improved the readability of 4- to 7-pixel-high scene text significantly better than bicubic interpolation and increased the accuracy of OCR results better than the piecewise smoothness prior. 相似文献
63.
64.
Medium-sulfur bituminous coal and a mixture of 95 wt.% coal plus 5 wt.% tire-derived fuel (TDF) in the form of shredded automotive tires were combusted in a stoker boiler under the same conditions. This paper presents quantitative chemical compositions of the fuels and of the gaseous and particulate emissions. The coal + TDF mixture is considerably richer in Zn than the pure coal as a result of the high Zn content of the shredded tires (∼1 wt.% Zn). Atmospheric emissions of Zn increased from 15 g/h to nearly 2.4 kg/h when coal + TDF was combusted. Similarly, emissions of most other metals and metalloids, as well as those of HCl increased when TDF (∼3000 ppm Cl) was added. The enhanced metal emissions might be due to formation of gaseous metal chloride species in the stack gases. On the other hand, emissions of CO decreased slightly, whereas those of NOx, SO2, and total particulate matter remained virtually unchanged. These results help in assessing the environmental impact of energy recovery from scrap tires in stoker boilers. 相似文献
65.
Sandi W. Smith Stacy L. Smith Katherine M. Pieper Jina H. Yoo Amber L. Ferris Edward Downs & Becka Bowden 《The Journal of communication》2006,56(4):707-727
Using a representative sample of television content featuring 2,227 programs across different genres and 18 different channels, the frequency and context of altruistic actions were content analyzed. A social cognitive theory approach was taken to guide the selection of contextual variables. The results showed that 73% of the programs in the sample featured instances of helping/sharing at a rate of 2.92 incidents per hour. Further, the actions were most likely to be initiated by adult White males and many acts were depicted in a humorous, realistic, and rewarding context. In terms of channel differences, shows on children's basic cable featured not only the highest proportion of programs with one or more instances of altruism but also the highest rate per hour (4.02 acts). Differences in contextual features and channel type are discussed in terms of social cognitive theory below. 相似文献
66.
Lichtenberg James W.; Wettersten Kara B.; Mull Holly; Moberly Rebecca L.; Merkley Katherine B.; Corey Amy Tiongson 《Canadian Metallurgical Quarterly》1998,45(3):322
This study examined the nature of therapist–client interactions within and across seven psychotherapy cases (a) to test whether therapeutic outcome is a function of a transition from relational incongruence to relational congruence (S. Strong, 1982), and (b) to investigate the relation of relational congruence and control to qualitative aspects of the therapy relationship and to therapy outcome. Measures of therapist and client response patterning served as indices of relational congruence and of relational control. Relationship quality was assessed in terms of therapist and client ratings of their working alliance and of therapy session depth and smoothness. Outcome was operationalized in terms of symptom reduction. Results showed limited support for a relationship between relational congruence and therapy outcome and suggested that relational control is not a significant factor in client or therapist evaluations of relationship quality or therapy outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Dr Katherine Jones 《International Journal of Network Management》1993,3(1):45-48
The third in a serieson the FDDI standard, this article looksatSMT–the Fibre Distributed Data Interface Station Management–and the directions for FDDI over copper cables. 相似文献
68.
This paper examines a variety of outcome indicators that might be used by an engineering program in meeting the assessment requirements of ABET Engineering Criteria 2000. Several categories of indicator are identified and key characteristics of these means of assessment are discussed. Also noted are some of the engineering applications of outcome indicators documented on the World Wide Web. Finally, the results of a recent telephone/fax survey on the use of outcome indicators in engineering program assessment are summarized. 相似文献
69.
Shortencarier MJ Dayton PA Bloch SH Schumann PA Matsunaga TO Ferrara KW 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(7):822-831
We have developed a method using ultrasound and acoustically active lipospheres (AALs) that might be used to deliver bioactive substances to the vascular endothelium. The AALs consist of a small gas bubble surrounded by a thick oil shell and enclosed by an outermost lipid layer. The AALs are similar to ultrasound contrast agents: they can be nondestructively deflected using ultrasound radiation force, and fragmented with high-intensity ultrasound pulses. The lipid-oil complex might be used to carry bioactive substances at high concentrations. An optimized sequence of ultrasound pulses can deflect the AALs toward a vessel wall then disrupt them, painting their contents across the vascular endothelium. This paper presents results from a series of in vitro and ex vivo experiments demonstrating localization of a fluorescent model drug. In experiments using a human melanoma cell (A2085) monolayer, a specific radiation force-fragmentation ultrasound pulse sequence increased cell fluorescence more than 10-fold over no ultrasound or fragmentation pulses alone, and by 50% over radiation force pulses alone. We observe that dye transfer is limited to cells that are in the region of ultrasonic focus, indicating that the application of radiation force pulses to bring the delivery vehicle into proximity with the cell is required for successful adhesion of the vehicle fragments to the cell membrane. We also demonstrate dye transfer from flowing AALs, both in a mimetic vessel and in excised rat cecum. We believe that this method could be successfully used for drug delivery in vivo. 相似文献
70.
A top-down approach based on sustained off-resonance irradiation collision-induced dissociation (SORI-CID) has been implemented on an electrospray ionization (ESI) Fourier transform mass spectrometer (FTMS) to characterize nucleic acid substrates modified by structural probes. Solvent accessibility reagents, such as dimethyl sulfate (DMS), 1-cyclohexyl-3-(2-morpholinoethyl)carbodiimide metho-p-toluenesulfonate (CMCT), and beta-ethoxy-alpha-ketobutyraldehyde (kethoxal, KT) are widely employed to reveal the position of single- vs double-stranded regions and obtain the footprint of bound proteins onto nucleic acids structures. Established methods require end-labeling of the nucleic acid constructs, probe-specific chemistry to produce strand cleavage at the modified nucleotides, and analysis by polyacrylamide gel electrophoresis to determine the position of the susceptible sites. However, these labor-intensive procedures can be avoided when mass spectrometry is used to identify the probe-induced modifications from their characteristic mass signatures. In particular, ESI-FTMS can be directly employed to monitor the conditions of probe application to avoid excessive alkylation, which could induce unwanted distortion or defolding of the substrate of interest. The sequence position of the covalent modifications can be subsequently obtained from classic tandem techniques, which allow for the analysis of individual target adducts present in complex reaction mixtures with no need for separation techniques. Selection and activation by SORI-CID has been employed to reveal the position of adducts in nucleic acid substrates in excess of 6 kDa. The stability of the different covalent modifications under SORI-CID conditions was investigated. Multiple stages of isolation and activation were employed in MS(n)() experiments to obtain the desired sequence information whenever the adduct stability was not particularly favorable, and SORI-CID induced the facile loss of the modified base. A new program called MS2Links was developed for the automated reduction and interpretation of fragmentation data obtained from modified nucleic acids. Based on an algorithm that searches for plausible isotopic patterns, the data reduction module is capable of discriminating legitimate signals from noise spikes of comparable intensity. The fragment identification module calculates the monoisotopic mass of ion products expected from a certain sequence and user-defined covalent modifications, which are finally matched with the signals selected by the data reduction program. Considering that MS2Links can generate similar fragment libraries for peptides and their covalent conjugates with other peptides or nucleic acids, this program provides an integrated platform for the structural investigation of protein-nucleic acid complexes based on cross-linking strategies and top-down ESI-FTMS. 相似文献