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261.
Video shot characterization 总被引:1,自引:0,他引:1
This paper presents a practical approach to detecting shot cuts and extracting keyframes from video sequences. Shot cut detection has two stages - global motion compensation, followed by an adaptive thresholding algorithm. The motion information is further utilized to extract representative keyframes. Special consideration has been given to achieving real-time performance on a regular PC, which led to a motion estimation algorithm of linear complexity.Received: 1 September 2003, Accepted: 12 March 2004, Published online: 8 June 2004
Correspondence to: Mihai OsianResearch supported by the EC project VIBES 相似文献
262.
263.
Mihai Oltean 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2007,11(6):503-518
A new model for evolving evolutionary algorithms (EAs) is proposed in this paper. The model is based on the multi expression
programming (MEP) technique. Each MEP chromosome encodes an evolutionary pattern which is repeatedly used for generating the
individuals of a new generation. The evolved pattern is embedded into a standard evolutionary scheme which is used for solving
a particular problem. Several evolutionary algorithms for function optimization are evolved by using the considered model.
The evolved evolutionary algorithms are compared with a human-designed genetic algorithm. Numerical experiments show that
the evolved evolutionary algorithms can compete with standard approaches for several well-known benchmarking problems. 相似文献
264.
In this paper, the length scaling of the silicon Double Gate Tunnel Field Effect Transistor (DG Tunnel FET) is studied. It is found that scaling limits are reached sooner by Tunnel FETs with an SiO2 gate dielectric, while those with a high-K dielectric can be scaled further before threshold voltage, and average and point subthreshold swing are affected. It is demonstrated that the scaling of the high-K Tunnel FET is completely different than that of conventional MOS transistors. An outstanding feature of the Tunnel FET switch is that length scaling has a much weaker impact on device characteristics than does gate control (e.g. the use of a high-K dielectric), which primarily dictates the tunneling barrier width and consequently, device conduction. This paper demonstrates that while some improvements are observed, the length scaling does not dramatically affect switch figures of merit such as subthreshold slope, Ion and Ioff down to about 20 nm, and an optimized device design can be extended over a much larger window of sub-micron dimensions, compared to the MOSFET. A discussion of the length dependence of the transconductance, gm, and output conductance, gds of the Tunnel FET is presented for the first time. 相似文献
265.
Luminita L. Ionescu-Vasii Mihai D. Dimonie Marc J. M. Abadie 《Polymer International》1998,47(2):221-225
A kinetic model for the photoinduced polymerization of phenyl glycidyl ether with a sulphonium salt as photoinitiator obtained from Union Carbide is presented. The kinetics of the photoinduced reactions were monitored by differential photocalorimetry (DPC). © 1998 Society of Chemical Industry 相似文献
266.
Mark Ainsworth L. Angela Mihai 《International journal for numerical methods in engineering》2009,78(10):1135-1163
We present an adaptive multi‐scale approach for predicting the mechanical behaviour of masonry structures modelled as dynamic frictional multi‐body contact problems. In this approach, the iterative splitting of the contact problem into normal contact and frictional contact is combined with a semismooth Newton/primal‐dual active‐set procedure to calculate deformations and openings in the model structures. This algorithm is then coupled with a novel adaptive multi‐scale technique involving a macroscopic scale, which is the size of the masonry structure, and a mesoscopic scale, which is the size of the constituents (bricks, stone‐blocks), to predict appearance of dislocations and stress distribution in large‐scale masonry structures. Comparisons of the numerical results with data from experimental tests and from practical observations illustrate the predictive capability of the multi‐scale algorithm. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
267.
Claudia Gordin Christelle Delaite Sophie Bistac Daniela Rusu Mihai Rusu 《Polymer Bulletin》2009,63(4):517-529
Poly(vinyl chloride)/poly(ε-caprolactone)/poly(ε-caprolactone)-b-poly(dimethylsiloxane) [PVC/PCL/(PCL-b-PDMS)] blends were
prepared by solvent casting from tetrahydrofuran. The content of PVC was kept constant (60 wt%); the PCL and PCL-b-PDMS contents
were varied by replacing different amounts of PCL [0–20 wt% from the PVC/PCL (60/40) blend] with PCL-b-PDMS copolymer having
different molecular weights of the PCL blocks. The thermal properties of prepared blends were investigated by differential
scanning calorimetry in order to analyse miscibility (through glass transition temperature) and crystallinity. Differential
scanning calorimetry analyses show that the PVC/PCL/PCL-b-PDMS blends are multi-phase materials which contain a PVC plasticized
with PCL phase, a block copolymer PCL-b-PDMS phase (with crystalline and amorphous PCL and PDMS domains) and a PCL phase (preponderantly
crystalline). 相似文献
268.
269.
Ionut Luchian Ancuta Goriuc Darius Sandu Mihai Covasa 《International journal of molecular sciences》2022,23(3)
Severe periodontitis, a destructive inflammatory disease of the supporting tissues of the teeth, ranks sixth in terms of global spread, affecting about 11% of the population. Metalloproteinases (MMPs) are extracellular matrix (ECM) macromolecules that are important in cellular development and morphogenesis, and they are capable of activating growth factors in their proximity, cell surface receptors, and adhesion molecules. MMPs are part of a major family of zinc-dependent endopeptidases, and their activity is modulated and regulated by certain inhibitors known as tissue metalloproteinase inhibitors (TIMPs). Because type I collagen is the major component of the periodontal extracellular matrix, special attention has been paid to the role of collagenases, especially MMP-8 and MMP-13 and gelatinases, MMP-2 and MMP-9, in periodontal diseases. In fact, MMP-8 (or collagenase 2) is currently one of the most promising biomarkers for periodontitis in oral fluids. Among them, salivary MMP-9 has been shown to be a more sensitive marker for periodontal inflammation during orthodontic treatment, which opens new perspectives in reducing periodontal hazards during such treatments. Both MMP-8 and MMP-9 are extremely valuable diagnostic tools in treating periodontitis, and future studies and healthcare policies should focus on implementing more accessible methods of chairside testing in order to reduce the prevalence of this disease. 相似文献
270.
Valentina Anua Marina-Theodora Talianu Cristina-Elena Dinu-Pîrvu Mihaela Violeta Ghica Rzvan Mihai Prisada Mdlina Georgiana Albu Kaya Lcrmioara Popa 《International journal of molecular sciences》2022,23(14)
Oral candidiasis has a high rate of development, especially in immunocompromised patients. Immunosuppressive and cytotoxic therapies in hospitalized HIV and cancer patients are known to induce the poor management of adverse reactions, where local and systemic candidiasis become highly resistant to conventional antifungal therapy. The development of oral candidiasis is triggered by several mechanisms that determine oral epithelium imbalances, resulting in poor local defense and a delayed immune system response. As a result, pathogenic fungi colonies disseminate and form resistant biofilms, promoting serious challenges in initiating a proper therapeutic protocol. Hence, this study of the literature aimed to discuss possibilities and new trends through antifungal therapy for buccal drug administration. A large number of studies explored the antifungal activity of new agents or synergic components that may enhance the effect of classic drugs. It was of significant interest to find connections between smart biomaterials and their activity, to find molecular responses and mechanisms that can conquer the multidrug resistance of fungi strains, and to transpose them into a molecular map. Overall, attention is focused on the nanocolloids domain, nanoparticles, nanocomposite synthesis, and the design of polymeric platforms to satisfy sustained antifungal activity and high biocompatibility with the oral mucosa. 相似文献