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991.
Image denoising using derotated complex wavelet coefficients 总被引:2,自引:0,他引:2
A method for removing additive Gaussian noise from digital images is described. It is based on statistical modeling of the coefficients of a redundant, oriented, complex multiscale transform. Two types of modeling are used to model the wavelet coefficients. Both are based on Gaussian scale mixture (GSM) modeling of neighborhoods of coefficients at adjacent locations and scales. Modeling of edge and ridge discontinuities is performed using wavelet coefficients derotated by twice the phase of the coefficient at the same location and the next coarser scale. Other areas are modeled using standard wavelet coefficients. An adaptive Bayesian model selection framework is used to determine the modeling applied to each neighborhood. The proposed algorithm succeeds in providing improved denoising performance at structural image features, reducing ringing artifacts and enhancing sharpness, while avoiding degradation in other areas. The method outperforms previously published methods visually and in standard tests. 相似文献
992.
A multi-time period combined gas and electricity network optimisation model was developed. The optimisation model takes into account the varying nature of gas flows, network support facilities such as gas storage and the power ramping characteristics of electricity generation units. The combined optimisation is performed from an economic viewpoint, minimising the costs associated with gas supplies, linepack management, gas storage operation, electricity generation, and load shedding. It is demonstrated on the GB gas and electricity network. 相似文献
993.
Streptococcus suis present in raw pork meats sold in local retail markets was enumerated by Most Probable Number (MPN)-PCR method. This method combined the conventional MPN technique with a specifically designed PCR assay based on the amplification of a 294-bp S. suis species-specific 16S rRNA gene sequence. A total of 78 raw pork lean meat samples purchased at two different supermarkets (Site A and B) and a wet market (Site C) were tested. Results indicated that S. suis could be detected from the enriched MPN tubes of all, except one, sample homogenates. The concentration of S. suis ranged from <3 to 4600 MPN/g of pork meat, with a total bacterial count (TBC) varying from 3.6 log to 7.4 log CFU/g. Statistical analyses indicated that pork meats purchased from the supermarket at Site B in summer contained significantly higher concentration of S. suis organisms than those from other retailers in any season. A significant correlation existed between log S. suis concentration and log TBC of the samples. This study revealed that raw pork meats available in local supermarkets or wet markets could contain S. suis at concentrations that were usually difficult to detect with traditional culture method. Field application of this method may contribute to a measurable evaluation, and thus the effective control, of human S. suis infection due to raw pork or pig carcass handling. 相似文献
994.
995.
Saara Tuurala Otto-Ville Kaukoniemi Leo von Hertzen Johanna Uotila Anu Vaari Mikael Bergelin Pia Sjöberg Jan-Erik Eriksson Maria Smolander 《Journal of Applied Electrochemistry》2014,44(7):881-892
Production of printable enzymatic power sources was scaled up from laboratory to roll-to-roll (R2R) pilot production. The anode and cathode enzymes were glucose oxidase (GOx) and laccase, respectively. The best laboratory-scale cells had a maximum power and energy density of 1.4 ± 0.1 µW cm?2 and 5.5 ± 0.2 µWh cm?2, respectively. These values are 5 and 28 times higher compared to our previously published values. The R2R-produced cells had a maximum power and energy density of 0.40 ± 0.03 µW cm?2 and 0.6 ± 0.1 µWh cm?2, respectively. This is 11 % of the best laboratory manufactured cells. It is suspected that the decrease in electrochemical performance originates from the lower mediator amount and higher drying temperature than that of the laboratory produced cells. However, the trials conducted in this work showed that printed enzymatic active layers can be fabricated and dried with a rotary screen-printing machine in R2R process. Hence, fully printed GOx//laccase power sources could be produced from R2R on a large scale for printed electronics applications. 相似文献
996.
Ellen Van Droogenbroeck Leo Van Hove Steven Cordemans 《Color research and application》2018,43(1):110-113
In a recent article, Puccinelli et al. examine the effect of the color in which prices appear in print flyers on consumers' perceived savings. Puccinelli et al. find that the effect is moderated by gender: unlike female consumers, men think they are being offered a better deal when prices are presented in red than when they are presented in black. The advertisements with prices in red also put men in a more positive state. This note replicates Puccinelli et al.'s main experiment in a different context (online vs. print) and in a different cultural setting (Belgium vs. the USA). In line with Puccinelli et al., we find that men perceive the online store with red prices as offering better value. But, intriguingly, it does not appear to make men feel more positively. One possible explanation is that red prices work differently online. 相似文献
997.
998.
High‐temperature pyrolysis of natural gas is the basis of the standard method for the manufacture of acetylene. The study of methane pyrolysis was designed to find optimum process conditions that would produce high yields of acetylene with minimal carbon formation. High temperatures and short residence times enhanced the selectivity for acetylene, while hydrogen dilution was found to suppress the generation of carbonous products. Carbon formation on reactor surfaces over time may be mainly responsible for the misalignment of predicted and measured product gas compositions, as the mechanisms reported do not consider the surface chemistry. In essence, the pyrolysis system favors the highest possible temperature and shortest possible residence time, suggesting that the selection of reactor materials is the key for pyrolysis process optimization. The operating temperature is likely dictated by the physical properties of the reactor materials rather than the selection of optimal pyrolysis conditions. 相似文献
999.
Konstantinos Skobridis Prof. Maria Kinigopoulou Vassiliki Theodorou Prof. Emilia Giannousi Alison Russell Rakhee Chauhan Roberta Sala Nicola Brownlow Dr. Serafim Kiriakidis Dr. Jan Domin Dr. Andreas G. Tzakos Dr. Nick J. Dibb Dr. 《ChemMedChem》2010,5(1):130-139
Imatinib is a clinically important ATP analogue inhibitor that targets the tyrosine kinase domain of the intracellular Abl kinase and the PDGF receptor family. Imatinib has revolutionised the treatment of chronic myeloid leukaemia, which is caused by the oncogene Bcr–Abl and certain solid tumours that harbor oncogenic mutations of the PDGF receptor family. As a leading kinase inhibitor, imatinib also provides an excellent model system to investigate how changes in drug design impact biological activity, which is an important consideration for rational drug design. Herein we report a new series of imatinib derivatives that in general have greater activity against the family of PDGF receptors and poorer activity against Abl, as a result of modifications of the phenyl and N‐methylpiperazine rings. These new compounds provide a platform for further drug development against the therapeutically important PDGF receptor family and they also provide insight into the engineering of drugs with altered biological activity. 相似文献
1000.
Ulrike Groenhagen Rita Baumgartner Aurélien Bailly Amber Gardiner Leo Eberl Stefan Schulz Laure Weisskopf 《Journal of chemical ecology》2013,39(7):892-906
Increasing evidence indicates that volatile compounds emitted by bacteria can influence the growth of other organisms. In this study, the volatiles produced by three different strains of Burkholderia ambifaria were analysed and their effects on the growth of plants and fungi, as well as on the antibiotic resistance of target bacteria, were assessed. Burkholderia ambifaria emitted highly bioactive volatiles independently of the strain origin (clinical environment, rhizosphere of pea, roots of maize). These volatile blends induced significant biomass increase in the model plant Arabidopsis thaliana as well as growth inhibition of two phytopathogenic fungi (Rhizoctonia solani and Alternaria alternata). In Escherichia coli exposed to the volatiles of B. ambifaria, resistance to the aminoglycoside antibiotics gentamicin and kanamycin was found to be increased. The volatile blends of the three strains were similar, and dimethyl disulfide was the most abundant compound. Sulfur compounds, ketones, and aromatic compounds were major groups in all three volatile profiles. When applied as pure substance, dimethyl disulfide led to increased plant biomass, as did acetophenone and 3-hexanone. Significant fungal growth reduction was observed with high concentrations of dimethyl di- and trisulfide, 4-octanone, S-methyl methanethiosulphonate, 1-phenylpropan-1-one, and 2-undecanone, while dimethyl trisulfide, 1-methylthio-3-pentanone, and o-aminoacetophenone increased resistance of E. coli to aminoglycosides. Comparison of the volatile profile produced by an engineered mutant impaired in quorum-sensing (QS) signalling with the corresponding wild-type led to the conclusion that QS is not involved in the regulation of volatile production in B. ambifaria LMG strain 19182. 相似文献