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1.
An accurate printer model that is efficient enough to be used by halftoning algorithms is proposed. The proposed signal processing model (SPM) utilizes a physical model to train adaptive linear combiners (ALCs), after which the average exposure of each subpixel for any input pattern can be calculated using the optimized weight vector. The SPM can be used to model multi-level halftoning and resolution enhancement, as well as traditional halftoning. The SPM is comprised of a single ALC layer followed by a peak-to-average ratio (PAR) correction layer, which serves to produce a PAR of less than 1.5 in the modeled exposure. The PCN (PAR correction network) employs one ALC/pixel and exploits the physics governing the characteristics of exposure in small regions. A relatively small number of training patterns suffices to train the SPM. 相似文献
2.
NP Kirilenko 《Canadian Metallurgical Quarterly》1993,38(9):13-15
Levels of temporary invalidity because of catching cold were analyzed in 101 working women over two years and these women's levels of serum iron, total iron-binding capacity of the serum, transferrin saturation with iron, serum ferritin, and red cell ferritin measured. Women with stable iron reserves in the body virtually have no sick leaves because of catching cold, whereas in those with iron deficiency susceptibility to catching cold is increased, and if iron metabolism intensity in the body grows, invalidity periods are much longer. Normalization of not only iron reserves in the body, but correction of iron metabolism as well should be regarded as a factor exerting a favorable effect on body resistance to catching cold. 相似文献
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JC Posnick MD Wells JM Drake JR Buncic D Armstrong 《Canadian Metallurgical Quarterly》1993,19(5):260-266
Fibrous dysplasia is an abnormal fibroosseous process of bone of unknown cause. The incidence of skull involvement varies, painless enlargement being the most common presenting symptom. Change in vision is a rare but recognized finding. We report a 3-year-old boy with extreme fibrous dysplasia involving the skull base, who presented with blindness. He underwent exposure osteotomies of the frontal bones and orbits to provide access for skull base tumor removal. The orbital roofs were reconstructed with microplate-fixed cranial grafts. One and one half years after tumor excision followed by immediate reconstruction, the boy retains facial symmetry, and his ocular function has not deteriorated. 相似文献
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Continuous simulation is performed using the US Environmental Protection Agency (USEPA) Storm Water Management Model (SWMM) to evaluate regional differences around the United States in hydrologic and water quality performance of wet-weather controls. Controls are characterised as being limited by peak inflow rate (i.e. any device with little or no storage, such as screens, filters and some proprietary devices) or by storage capacity (e.g., ponds, tanks). For flow-limited devices, results are presented in the form of percentage of annual runoff volume captured (passing through the device) for a given inflow capacity. For storage-limited devices, results are presented in two forms: percentage of annual runoff volume captured as a function of unit basin size and drawdown (drain) time, and as a percentage of total suspended solids captured, for the same two variables. Regional differences are apparent, driven mainly by variations in rainfall patterns around the country. 相似文献
7.
The Magtalo prototype environment harnesses dialogue protocols to support flexible, intuitive interaction with data in complex, contentious domains and provides mechanisms for eliciting structured knowledge. Magtalo represents the first example of an implemented online system that uses a closely specified argument-based dialogue protocol combined with a rich language for representing monologic argument to provide a tool for intuitive user exploration of a disagreement space. This approach also enables the expansion of argument resources through knowledge elicitation, which is structured by the argument dialogue protocol. The continuing aim of our research is to use advances in argumentation theory to push the practice of argumentation technology in providing tools and interfaces that have wide appeal. 相似文献
8.
We describe in this report a sensitive and direct method for the analysis of tamoxifen (TAM) in microsamples of plasma. The drug and internal standard (quinine bisulfate, I.S.) were separated on a 10-microm particle, 10 cm X 8 mm CN cartridge in conjunction with a radial compression system. The mobile phase was a mixture of 0.1 M sodium acetate in 0.001 M tetrabutylammonium phosphate solution (pH 6) and methanol (30:70, v/v) at a flow-rate of 4 ml/min. After addition of I.S. and o-phosphoric acid in acetonitrile (0.6 M) to the plasma (30 microl), the mixture was placed in an ultraviolet shortwave transluminator for 2 min prior to injection into the chromatograph. The compounds were detected in the effluent fluorometrically at excitation and emission wavelengths of 258 and 378 nm, respectively. Under these conditions, no interference in the assay from any endogenous substance or other concurrently used drugs was observed and the retention times of I.S. and TAM were 4.4 and 10.15 min, respectively. The concentration of TAM in plasma was linearly (r>0.9983) related to the peak height ratio (TAM/I.S.) in the range 0.01-2.0 microg ml(-1) and C.V. at 0.075, 0.4 and 1.2 microg ml(-1) was < or = 4.96%. We are currently using this assay for monitoring TAM in plasma and investigating its pharmacokinetics in cancer patients receiving cytotoxic drugs in addition to TAM as a multi-drug resistance modifier. 相似文献
9.
Examined the job performance of 420 credit managers (mean age at hiring 25 yrs) from a large finance company who either quit their job, were fired, or were promoted to a higher position in the company. Six biographical variables and 12 performance appraisal scores accumulated from data in employee files were used in a cross-validated multiple discriminant analysis to predict membership in the 3 classification groups. Results reveal a systematic relation between the performance appraisal variables and the classification groups: The performance of promoted Ss was significantly superior to that of Ss who quit, which in turn was significantly superior to the performance of the fired Ss. 18 discriminating variables accounted for a 46.7% hit rate in group membership. Findings are discussed in the context of research on performance antecedents of voluntary and involuntary turnover, as well as the feedback properties of performance appraisal information. It is suggested that no single performance–turnover relation exists. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
A Fassati A Bardoni M Sironi DJ Wells N Bresolin G Scarlato M Hatanaka S Yamaoka G Dickson 《Canadian Metallurgical Quarterly》1998,9(17):2459-2468