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Based on the existing image mosaic technology, this paper introduces the granular computing and obtains a simplified new algorithm. The image mosaic executed by this algorithm at first establishes correlation model on the basis of granular computing theory, and obtains edge map of each image needing mosaic. The new calculation method is used to calculate gradient of in different columns of edge map, to obtain the feature point coordinates with the maximum gradient; meanwhile, all feature points of two images are matched with each other, to acquire the best matching point. In addition, the error-correcting mechanism is introduced in the matching process, which is used to delete feature points with matching error. The correlation calculation is carried out for the matching pixels acquired by the above processing, to get the feature transformational matrix of the two images. According to the matrix, two separated image maps map into the same plane. The slow transitional mosaic method is applied in the aspect of image addition plus overlap removal, so that images have no bulgy boundary after mosaics. The whole image mosaic process shows that the given granular computing algorithm is superior to the traditional one both in the number of processed images and the number of processing, and the mosaic image gained has high quality.

The relative intensity noise (RIN) and relaxation oscillation characteristics of distributed-feedback fiber lasers (DFB-FLs) have been investigated theoretically and experimentally. The effects of Er3+ doping concentration and phase-shift grating parameters such as the coupling coefficient on the RIN and relaxation oscillation characteristics of DFB-FLs are presented by an analytical model. Also, four DFB-FLs with dissimilar coupling coefficients are fabricated and tested to confirm the theoretical results. In addition, the influence of the external environment and the contribution of the pump power fluctuations are analyzed in detail by experiments.

Background Vitamin D deficiency is associated with a variety of chronic metabolic diseases. Limited evidence regarding vitamin D deficiency exists within the Chinese population. The present study aims to examine the association between serum vitamin D concentrations and cardiometabolic risk factors in the young and middle-aged, urban Chinese population Methods The cross-sectional relationships between serum 25-hydroxyvitamin D [25(OH)D] concentrations and indices of adiposity and cardiometabolic risk factors (e.g., body mass index, waist circumference, fasting plasma glucose, etc.) were evaluated in 601 non-diabetic adults. Result Vitamin D deficiency or insufficiency was present in 66% of the tested population, and serum 25(OH)D levels were lower in patients who were overweight/obese or suffered metabolic syndrome when compared to individuals of healthy weight without metabolic syndrome (24.08 ± 8.08 vs 31.70 ± 11.77 ng/ml, 21.52 ± 6.9 vs 31.74 ± 10.21 ng/ml respectively). 25(OH)D was inversely associated with waist circumference, fasting glucose, fasting insulin, triglycerides and LDL-cholesterol, and it was positively associated with HDL-cholesterol in a multivariable-adjusted regression model. Conclusion Vitamin D deficiency is common in the young and middle-aged, urban Chinese population, with high prevalence in overweight/obese individuals and patients with metabolic syndrome. Low vitamin D concentration was associated with indices of adiposity and cardiometabolic risk factors. Further studies are warranted to elucidate the cause-effect relation between vitamin D status, obesity and related metabolic disorders. Trial registration Current Controlled Trials (ISRCTN21527585)

In this paper, a newly developed gateable SEC tube is presented. Structure, operating principle, and performance of the tube are introduced in detail. Features and preparation of a new mesh-supported target are described. An experiment system, in which combination of selectable switching on and integrating capability of the new gateable SEC tube is used for fluorescence image detection, is given.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

On basis of the geometric mean proposed recently by T. Ando, Chi-Kwong Li and Roy Mathias, in this paper we present several kinds of mixed means for three or more positive definite matrices, and prove some related mixed mean inequalities.