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71.
Michael Jiang Michael Groble Andrij Neczwid Allan Willey 《Journal of Visual Languages and Computing》2006,17(6):584
Visual modeling languages and techniques have been increasingly adopted for software specification, design, development, and testing. With the major improvements of UML 2.0 and tools support, visual modeling technologies have significant potential for simplifying design, facilitating collaborations, and reducing development cost. In this paper, we describe our practices and experiences of applying visual modeling techniques to the design and development of real-time wireless communication systems within Motorola. A model-driven engineering approach of integrating visual modeling with development and validation is described. Results, issues, and our viewpoints are also discussed. 相似文献
72.
Design and Use of Linear Models for Image Motion Analysis 总被引:7,自引:1,他引:6
Fleet David J. Black Michael J. Yacoob Yaser Jepson Allan D. 《International Journal of Computer Vision》2000,36(3):171-193
Linear parameterized models of optical flow, particularly affine models, have become widespread in image motion analysis. The linear model coefficients are straightforward to estimate, and they provide reliable estimates of the optical flow of smooth surfaces. Here we explore the use of parameterized motion models that represent much more varied and complex motions. Our goals are threefold: to construct linear bases for complex motion phenomena; to estimate the coefficients of these linear models; and to recognize or classify image motions from the estimated coefficients. We consider two broad classes of motions: i) generic motion features such as motion discontinuities and moving bars; and ii) non-rigid, object-specific, motions such as the motion of human mouths. For motion features we construct a basis of steerable flow fields that approximate the motion features. For object-specific motions we construct basis flow fields from example motions using principal component analysis. In both cases, the model coefficients can be estimated directly from spatiotemporal image derivatives with a robust, multi-resolution scheme. Finally, we show how these model coefficients can be use to detect and recognize specific motions such as occlusion boundaries and facial expressions. 相似文献
73.
Neutral glycolipids (NGL) are promising diagnostic markers of human gliomas, but differences in NGL with age and sex have
not been examined. Previous work demonstrated that ceramide dihexosides (CDH) levels in mouse kidney are age- and sex-dependent,
probably due to levels of sex hormones. We quantitated CDH in 181 human gliomas and found significant differences with sex
and age, particularly menopause and male puberty. This emphasizes the importance of assessing results of studies on glycolipids
in disease states with respect to age and sex in order to avoid erroneous conclusions concerning the relationship of glycolipid
composition with diagnosis and pathogenesis. 相似文献
74.
Rios M.A. Kirschen D.S. Jayaweera D. Nedic D.P. Allan R.N. 《Power Systems, IEEE Transactions on》2002,17(3):543-548
Deterministic security criteria provide a degree of security that may be insufficient under some operating conditions and excessive for others. To determine an appropriate level of security, one should perform a probabilistic cost/benefit analysis that balances the cost of the security margin against its benefits, i.e., the expected societal cost of the avoided outages. This paper shows how a previously published method based on Monte Carlo simulation can be enhanced to take into account time-dependent phenomena (TDP) such as cascade tripping of elements due to overloads, malfunction of the protection system, and potential power system instabilities. In addition, the importance of using failure rates that reflect the weather conditions is discussed. Studies based on the South-Western part of the transmission network of England and Wales demonstrate the validity of the models that have been developed. 相似文献
75.
76.
In Alberta, cellulitis condemnations average 0.5% and are among the highest in Canada. Presently, all cellulitis-affected birds are condemned for fear of systemic infections and public health implications. In a slaughterhouse sample of 102 birds condemned with cellulitis, Escherichia coli was isolated from 83.3% of the lesions. All hearts were cultured and from 11.2% E. coli was recovered. Gross lesions of perihepatitis, infected oviducts, and arthritis were found in 11.2%, 6.7%, and 2.9% of the birds, respectively. Serotyping suggested that visceral infection occurs independent of cellulitis in at least half of the cases. There was no correlation between microscopic visceral lesions and positive bacterial cultures. Two E. coli isolates of serogroup 0157 produced no toxin and neither isolate produced CS31A, F107, or F1845 fimbriae. Cellulitis lesions ranged from 0.55 to 218.9 cm2. All lesions under 16 cm2 and 64% of lesions up to 48 cm2 were considered suitable for trimming. 相似文献
77.
AIM: The study of clinical running of gastric or duodenal ulcer in associated coronary heart disease (CHD). MATERIALS AND METHODS: 209 CHD patients with gastric ulcer (GU) or duodenal ulcer (DU) were examined clinically plus histological examination of gastric or duodenal mucosa biopsies was made. RESULTS: In CHD patients GU occurred more frequently (56%) than DU. The lesions involved more frequently lesser curvature of the stomach and pyloric part of the stomach. Males developed ulcers 3.5 times more frequently than females. Ulcers tended to a painless course without season exacerbations. The disease manifested first with gastric bleeding in 52% of the patients. GU and DU ran with frequent recurrences and long-term exacerbations (76% of patients) which coincided in time with CHD exacerbations. 68% of patients developed exacerbations within 10 days after myocardial infarction or aortocoronary bypass operation. Helicobacter pylori was present as a resolving factor in arising ulcer in 26% of patients. Microcirculatory disorders, reduced blood flow speed in gastric or duodenal mucosa, hypocoagulation syndrome, dyslipidemia provoked exacerbations in 62% of patients. Examinations of biopsies from gastric and duodenal mucosa showed marked dystrophic changes in the mucosa, its connective tissue basis in the vessels in the presence of mild inflammation at ulcer site. CONCLUSION: The onset of ulcers and erosions in the mucosa of the gastrointestinal tract in CHD may be due to circulatory disorders in gastric mucosa. The main factors of aggression are hypoxia, hypoxia-induced trophic defects in gastric and duodenal mucosa, circulatory disorders. 相似文献
78.
LA Pagan-Carlo JJ Allan KT Spencer CL Birkett R Myers RE Kerber 《Canadian Metallurgical Quarterly》1998,32(7):2065-2071
OBJECTIVES: This study was performed to determine the efficacy of new encircling overlapping multipulse, multipathway waveforms for transthoracic defibrillation. BACKGROUND: Alternative waveforms for transthoracic defibrillation may improve shock success. METHODS: First, we determined the shock success achieved by three different waveforms at varying energies (18-150 J) in 21 mongrel dogs after short-duration ventricular fibrillation. The waveforms tested included the traditional damped sinusoidal waveform, a single pathway biphasic waveform, and a new encircling overlapping multipulse waveform delivered from six electrode pads oriented circumferentially. Second, in 11 swine we compared the efficacy of encircling overlapping multipulse shocks given from six electrode pads and three capacitors versus encircling overlapping shocks given from a device utilizing three electrodes and one capacitor. RESULTS: In the first experiment, the encircling overlapping waveform performed significantly better than biphasic and damped sinusoidal waveforms at lower energies. The shock success rate of the overlapping waveform (six pads) ranged from 67+/-4% (at 18-49 J energy) to 99+/-3% at > or = 150 J; at comparable energies biphasic waveform shock success ranged from 26+/-5% (p < 0.01 vs. encircling overlapping waveforms) to 99+/-5% (p = NS). Damped sinusoidal waveform shock success ranged from 4+/-1% (p < 0.01 vs. encircling overlapping waveform) to 73+/-9% (p = NS). In the second experiment the three electrode pads, one capacitor encircling waveform achieved shock success rates comparable with the six-pad, three-capacitor waveform; at 18-49 J, success rates were 45+/-15% versus 57+/-12%, respectively (p = NS). At 100 J, success rates for both were 100%. CONCLUSIONS: We conclude that encircling overlapping multipulse multipathway waveforms facilitate transthoracic defibrillation at low energies. These waveforms can be generated from a device that requires only three electrodes and one capacitor. 相似文献
79.
80.
Results of a survey of 19 doctoral psychology programs indicate that the majority of faculty in university-affiliated free-standing professional programs are part-time, and their primary income and professional identity are outside the educational program. Questions are raised concerning faculty commitment to student education, financial viability and institutional stability, the history of free-standing schools in other professions, and whether psychology should continue to be based in the university. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献