Let C be a nonempty closed convex subset of a real Hilbert space H. Let S : C -> C be a non-expansive mapping and{T(i)}(i=1)(infinity) : C -> C be an infinite family of non-expansive mappings. The purpose of thi...
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Let C be a nonempty closed convex subset of a real Hilbert space H. Let S : C -> C be a non-expansive mapping and{T(i)}(i=1)(infinity) : C -> C be an infinite family of non-expansive mappings. The purpose of this paper is to find the minimum norm solution of the following general hierarchical fixed point problem Find (x) over tilde is an element of boolean AND(infinity)(n=1) Fix(T(n)) such that <(x) over tilde - S (x) over tilde, (x) over tilde - x > <= 0, for all x is an element of boolean AND(infinity)(n=1) Fix(T(n)). We introduce an explicit regularized algorithm with strong convergence for finding the minimum norm solution of the above hierarchical fixed point problem. (C) 2011 Elsevier Ltd. All rights reserved.
Purpose: To investigate influences of reconstruction algorithms and count statistics variation on quantification and treatment response assessment in cancer patients, by using a large field of view-FOV scanner. Method...
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Purpose: To investigate influences of reconstruction algorithms and count statistics variation on quantification and treatment response assessment in cancer patients, by using a large field of view-FOV scanner. Methods: 54 cancer patients underwent PET/CT scan: 1) at baseline: 1.5 min/FOV, reconstructed by ordered-subset expectation maximization + point-spread-function-OSEM-PSF and bayesian penalised-likelihood-BPL algorithm 2) at restaging: 2 min/FOV, reconstructed also at 1.5 and 1 min/FOV, using OSEM-PSF and BPL. SUL (lean-body mass SUV) peak and max were measured for each target-lesion (n = 59). Differences in quantification obtained from datasets with different reconstruction algorithms and different time/FOV were evaluated. For any pair of PET datasets, metabolic response was assessed by using SULpeak, with a threshold of 30% in variation considered as significant. Results: Both at baseline and restaging, SULpeak and max values were higher in BPL reconstructions than in OSEM-PSF (p < 0.0001). SULpeak at different time/FOV reconstructions showed no statistically significant differences both with OSEM-PSF and BPL;SULmax depended on acquisition time (p < 0.05). In 56/59 lesions (95%) therapy response was concordant regardless count statistics variation and reconstruction algorithm;2/59 (3%) showed different responses according to count statistics, both for OSEM-PSF and BPL;in 1/59 lesion (2%) response was different depending on reconstruction algorithm used. Conclusions: BPL provided higher SULpeak and max than OSEM-PSF. With a large FOV/high sensitivity scanner, variation of time/FOV in restaging PET scans gave stable and reproducible results in terms of SULpeak, both for OSEM-PSF and BPL. Thus, metabolic response defined by SULpeak variation proved to be quite independent from count statistics.
Research on inverse problems of textile material design, which are motivated from functional clothing industry, is an inspiring and promising research field in the inverse problems family. It is important to reveal he...
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Research on inverse problems of textile material design, which are motivated from functional clothing industry, is an inspiring and promising research field in the inverse problems family. It is important to reveal heat and moisture transfer characteristics in the system of human body-clothing-environment, which directly determines clothing heat-moisture comfort level. We present a comprehensive description on the mixed problems for coupled partial differential equations (in abbreviation, Direct Problems) based on dynamic heat and moisture transfer law with condensation in porous fabric. More importantly, we mathematically formulate novel inverse problems of textile material determination (in abbreviation, IPTMD) based on heat-moisture comfort indexes. The unique existence for the direct problems and numerical algorithms for IPTMD is reviewed. The further research topics are concluded to promote more fruitful achievements in the research of IPTMD in the near future.
Aiming at the problem that the multi-hop range-free wireless localization algorithm is sensitive to the influence of the anisotropic sensor network factors, we propose a new approach for localization in wireless senso...
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ISBN:
(纸本)9783319685052;9783319685045
Aiming at the problem that the multi-hop range-free wireless localization algorithm is sensitive to the influence of the anisotropic sensor network factors, we propose a new approach for localization in wireless sensor networks based on regularization algorithm. We first construct the mapping model using the hop-counts and the distance between anchors, and regularization algorithm is used to describe the optimal linear transformations between the hop-counts and the distance. We then use the hop-counts of no-anchors to anchors and this mapping model to the locations of the non-anchors. We evaluate our algorithm under irregular distribution of nodes and the uneven deployment of nodes, and analyze its performance. We also compare our approach with several existing approaches, and demonstrate our proposed algorithm can effectively avoid the network anisotropy.
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