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The aim of this paper is to examine a set of wavelet functions (wavelets) for implementation in a still image compression system and to highlight the benefit of this transform relating to today's methods. The paper discusses important features of wavelet transform in compression of still images, including the extent to which the quality of image is degraded by the process of wavelet compression and decompression. Image quality is measured objectively, using peak signal-to-noise ratio or picture quality scale, and subjectively, using perceived image quality. The effects of different wavelet functions, image contents and compression ratios are assessed. A comparison with a discrete-cosine-transform-based compression system is given. Our results provide a good reference for application developers to choose a good wavelet compression system for their application 相似文献
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A numerical model for nonlinear dynamic analysis of planar masonry‐infilled concrete and steel frames strengthened with composites is briefly presented. The model is quite simple and it can simulate main nonlinear effects of these structures. Besides modelling of nonlinear behavior of concrete, steel, masonry, plaster and soil, it can simulate nonlinearities at contact surfaces, changes in structural geometry and construction of a structure over different time phases. The model is based on a relatively small number of material parameters and intended for practical application primarily. The model is verified by using the data of the performed shake‐table tests on masonry‐infilled steel and concrete frames. Numerical results show fairly good agreement with the experimental results. This shows the potential reliability of the developed numerical model for the analysis of planar masonry structures. However, further verifications of the model and corresponding computational software are most welcome. 相似文献
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D. Grgic F. Homand A. Giraud 《International Journal of Rock Mechanics and Mining Sciences》2006,43(3):388-407
Mining collapses currently occur in Lorraine (France) above abandoned room-and-pillar iron mines during the transient stage of mine flooding. The mining rocks are exposed in situ to various hydrous conditions: full saturation–partial saturation (ventilation)–full saturation. In order to explain the mechanisms involved in mining collapses, we have performed one- and two-dimensional numerical simulations based on a poroplastic model and within the framework of partially saturated and continuous porous media. These numerical simulations model the hydrous cycle imposed to the rocks in these underground deep mines. It results from this hydromechanical modelling that the final stage of resaturation induces transient tensile stresses that lead to failures at the roof and at the floor of the galleries. These instabilities appear during the transient stage of resaturation only if the variation of the equivalent interstitial pressure π is important. The studied key points are the complex geometry of the model (rectangular rooms and dissymmetry of the upper and lower boundaries conditions) and the kinetics of the fluids diffusion processes that makes the reversibility very long and induces an important hysteresis in the hydromechanical cycle. The convergence measurements in an in situ experimental site, in which the flooding of the mine has been simulated, are well modelled. 相似文献
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Modern charging systems routinely apply the user, network, and service‐related information while performing online charging. Compared, however, to all the information available to and used in managing the network as a whole, the charging systems only use a limited subset. This work is motivated by the challenge to identify which information is used, and how it is used in online charging‐related processes, and also to explore whether it could be utilized ‘better’ or ‘smarter’ to improve future online charging systems functionality. We do not attempt to predict which information will be utilized in such systems and for what purpose, but instead summarize the open issues in view of the emerging trend of exploiting the user, network and service‐related information in service provisioning. We focus on the most recent 3GPP standards and relevant research papers, and propose three key aspects of online charging, with respect to information utilization: (a) signaling aspect, (b) inter‐domain aspect, and (c) service‐ and component‐based aspect. We present a state‐of‐the‐art review by grouping the works found in the literature based on the aspects they are associated with, and compare them based on the proposed comparison criteria. The discussion presented at the end of the paper indicates three common open issues, namely: (1) lack of common charging information specification and structure; (2) lack of mechanisms for information sharing among stakeholders in the service delivery process; and (3) lack of a common framework for sharing information while protecting user privacy. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Katarina Barbari Star
evi Nina Luka
Mislav Jeli Alan uur Danka Gr
evi Nataa Kova
i 《International journal of molecular sciences》2022,23(20)
Rheumatoid arthritis (RA) is chronic, autoimmune joint inflammation characterized by irreversible joint destruction. Besides increased resorption, destruction is a result of decreased bone formation, due to suppressed differentiation and function of the mesenchymal lineage-derived osteoblasts in inflammatory milieu. In this study, we analyzed the cellular composition of synovial tissue from 11 RA and 10 control patients harvested during planned surgeries in order to characterize resident synovial progenitor populations. Synovial cells were released by collagenase, and labeled for flow cytometry by two antibody panels: 1. CD3-FITC, CD14-PE, 7-AAD, CD11b-PECy7, CD235a-APC, CD19-APCeF780; and 2. 7-AAD, CD105-PECy7, CD45/CD31/CD235a-APC, and CD200-APCeF780. The proportions of lymphocytes (CD3+, CD19+) and myeloid (CD11b+, CD14+) cells were higher in synovial tissue from the patients with RA than in the controls. Among non-hematopoietic (CD45−CD31−CD235a−) cells, there was a decrease in the proportion of CD200+CD105− and increase in the proportion of CD200−CD105+ cells in synovial tissue from the patients with RA in comparison to the control patients. The proportions of both populations were associated with inflammatory activity and could discriminate between the RA and the controls. 相似文献
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Tomislav Sonja Mislav 《AEUE-International Journal of Electronics and Communications》2008,62(2):148-154
This paper presents a novel algorithm for intermodulation products counting in multicarrier systems. Intermodulation products are caused by the nonlinearity of the amplifiers’ transfer characteristic. Along the transmission network, broadband amplifiers are needed to boost up the signal level and compensate the signal attenuation. When the number of carriers increases, the number of intermodulation products also increases extremely fast. In our approach, selective counting procedure by grouping intermodulation products was introduced. The presented solution shows considerable reduction in computational effort in counting the number of intermodulation products in the individual channel, especially if the number of products is very large. 相似文献
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The concentration of reducing sugar in the urine is commonly used in the management of diabetes in children. Supplemental doses of regular insulin are administered in response to the concentration of urine sugar according to a protocol termed the "sliding scale." This practice assumes that the concentration of sugar in urine is a good indicator of the plasma glucose concentration. This assumption was tested by comparing urine sugar concentrations in first and second voided urines with the plasma glucose concentrations in 220 children with diabetes. The correlation was good (r = .92) for both the first and second voided urine specimens. Thus, urine sugar concentrations in general define the level of plasma glucose. The large standard deviation of the plasma glucose at each concentration of urine sugar, however, limits the usefulness of urine sugar as an accurate reflection of the coincident plasma glucose concentration. The urine sugar concentration, although useful for the general management of diabetes, provides significant risk when used to guide frequent adjustments in insulin administration. Therefore, the "sliding scale" should not be used in the treatment of children with diabetes. 相似文献
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In this paper, we present a new full-reference objective image quality measure—IQM2, based on structural similarity index and steerable pyramid wavelet transform. IQM2 is tested using different number of orientation kernels and seven subjective databases. Finally, IQM2 measure is compared with twelve commonly used full-reference objective measures. Results show that proposed IQM2 measure, using kernel with 2 orientations, provides good correlation with the results of subjective evaluation while keeping computational time lower than other similar performing objective measures. 相似文献