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排序方式: 共有442条查询结果,搜索用时 15 毫秒
1.
Ari Paasio Adam Dawidziuk Kari Halonen Veikko Porra 《Analog Integrated Circuits and Signal Processing》1997,12(1):59-70
The paper presents a Cellular Neural Network implementation based on a high gain sigmoid operation. The required simplifications to the original theory are described that allow the use of high gain. With this design black and white images can be processed. The basic building blocks in a cell are described. A 16×16 cells network has been designed and processed with 1.2 micron CMOS technology. Measurement results which show the operation of the network are presented. 相似文献
2.
Relaxed stability and performance conditions for Takagi-Sugeno fuzzy systems with knowledge on membership function overlap. 总被引:1,自引:0,他引:1
Antonio Sala Carlos Ari?o 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2007,37(3):727-732
This correspondence presents a relaxation of some earlier linear matrix inequality (LMI) conditions, which allow setting up less conservative stability or performance conditions for Takagi-Sugeno fuzzy models. Unlike the previous literature, this correspondence takes into account the knowledge of the membership functions' shape by considering bounds on them and their cross products (interpreted as an overlap measure), introducing auxiliary LMI variables. Numerical examples illustrate the achieved improvements. 相似文献
3.
DL Lundgren FF Hahn WC Griffith AF Hubbs KJ Nikula GJ Newton RG Cuddihy BB Boecker 《Canadian Metallurgical Quarterly》1996,146(5):525-535
This study was conducted to examine the carcinogenic effects of inhaled beta-particle-emitting radionuclides, particularly in lower dose regions in which there were substantial uncertainties associated with available information. A total of 2751 F344/N rats (1358 males and 1393 females) approximately 12 weeks of age at exposure were used. Of these, 1059 rats were exposed to aerosols of 144CeO2 to achieve mean desired initial lung burdens (ILBs) of 18 kBq (low level), 247 rats to achieve mean ILBs of 60 kBq (medium level) and 381 rats to achieve mean ILBs of 180 kBq (high level). Control rats (total of 1064) were exposed to aerosols of stable CeO2. Based on the 95% confidence intervals of the median survival times and the cumulative survival curves, there were no significant differences in the survival of groups of female and male exposed rats relative to controls. The mean lifetime beta-particle doses to the lungs of the rats in the four groups were: low level, 3.6 +/- 1.3 (+/-SD) Gy; medium level, 12 +/- 4.5 Gy; and high level, 37 +/- 5.9 Gy. The crude incidence of lung neoplasms increased linearly with increasing doses to the lungs (controls, 0.57%; low level, 2.0%; medium level, 6.1%; and high level, 19%). The estimated linear risk coefficients for lung neoplasms per unit of dose to the lung were not significantly different for the three dose levels studied. The risk coefficient at the lower level was 39 +/- 14 (+/-SE) excess lung neoplasms per 10(4) rat Gy; at the medium level the risk was 47 +/- 12; and at the higher level the risk was 50 +/- 9.0. The relationship of beta-particle dose to the lung and the crude incidence of lung neoplasms was described adequately by a linear function. We concluded that the risk of lung neoplasms in rats per unit of radiation dose did not increase with decreasing mean beta-particle dose to the lung over the range of 3.6 to 37 Gy. The weighted average of these three values was 47 +/- 6.4 (+/-SE) excess lung neoplasms per 10(4) rat Gy. To extend the risk coefficients for lung neoplasms to lower doses by experimentation will require much larger numbers of rats than used in this study. 相似文献
4.
Lung surfactant replacement has been tested clinically in recent years. In this study the outcome of 31 premature infants with moderate to severe neonatal respiratory distress syndrome (RDS) treated with surfactant was compared to that of 74 prematures with RDS treated conventionally by positive pressure ventilation and supportive care. The groups were well matched for gestational age, birthweight, sex, and Apgar scores at 1 and 5 min. Surfactant treatment resulted in a significant decrease in mortality--from 36.6% in the untreated group to 12.9% in the surfactant-treated group (P < 0.04). This improvement in survival was seen also in prematures with a birthweight < 1,000 g; in the untreated group mortality was 57.6% compared to 23.5% in the treated group (P < 0.05). The incidence of pneumothorax was lower in the treated group--42% vs. 13% (P < 0.01). Surfactant treatment resulted in a trend of more survivors without bronchopulmonary dysplasia or intraventricular hemorrhage, even though surfactant therapy did not change the incidence of either. 相似文献
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7.
Tiihonen P Kinnunen J Töyräs J Mervaala E Pääkkönen A 《Computer methods and programs in biomedicine》2008,89(1):83-92
Monitoring level of consciousness or depth of sedation is essential in modern intensive care units and emergency rooms. Current methods are based on spontaneous EEG providing only indirect information on the reactivity of the brain. Measurement of auditory event-related potentials (ERPs) has been shown to have additional potential for evaluation of the level of consciousness. Unfortunately, compact and easy-to-use devices are not commercially available. In this study a portable battery-powered device for clinical auditory ERP measurements was designed, constructed and validated. The device consists of a five-channel data logger and a 16-bit stereo audio stimulator. The signals are digitized with a 22-bit sigma-delta analogue-to-digital converter and stored to a PC Card hard disk. Prior to the in vivo application, the device was validated with extensive technical tests. Importantly, the RMS noise amplitude of the EEG channels was found to be less than 1 mivroV and the delivered auditory stimulus intensity corresponded accurately the settings (mean difference 0.2+/-0.5 dB). In addition to technical tests the device was successfully validated in vivo. To summarize, a novel portable instrument for measurement of auditory event-related potentials in intensive care environment is introduced. 相似文献
8.
Hemminki Ari; Hoffren Anna-Marja; Takkinen Kristiina; Vehniainen Markus; Makinen Maija-Liisa; Pettersson Kim; Teleman Olle; Soderlund Hans; Teeri Tuula T. 《Protein engineering, design & selection : PEDS》1995,8(2):185-191
Europium chelates provide a non-radioactive alternative forsensitive labelling of antibodies for diagnostic immunoassays.Lysine residues at antibody surfaces are ready targets for labellingby an isothiocyanate derivative of the europium chelate (Eu3+).Here the labelling efficiency of a recombinant anti-human -fetoprotein(hAFP) Fab fragment has been improved by increasing its lysinecontent by protein engineering. Molecular modelling was usedto identify three light chain constant domain surface arginineresidues, R154, R187 and R210, which were mutated to lysineresidues. The mutations did not influence the affinity of thelysine-enriched Fab fragment and its labelling efficiency wasfound to be 40% higher than that of the wildtype Fab fragmentWith low degree of labelling, the affinities of the two Fabfragments were identical and comparable with that of the originalmonoclonal anti-hAFP IgG. With a higher degree of labellingthe affinities of both Fab fragments decreased more than thatof the intact IgG since more lysine residues are available forlabelling in the additional heavy chain constant domains ofthe larger molecule. Electrostatic adsorption and covalent immobilizationof the Fab fragments were characterized by BIAcoreTM and thelysine-enriched Fab fragment was found to be more efficientlyimmobilized to an activated carboxymethyl surface. 相似文献
9.
During the production and recycling of asphalt concrete, bitumen in contact with inorganic particles is exposed to air at high temperatures. As a result an oxidation of bitumen, also known as aging, occurs. The reaction between bitumen and air at 163 °C was studied insitu with and without the presence of inorganic impurities by means of fourier transform infrared spectroscopy in the attenuated reflectance mode. This oxidation was discovered to be a step-wise reaction facilitated by the oxidation of thiols and creation of peroxides within the system. The rate of reaction was demonstrated to depend on the type of impurity present, of which iron (III) chloride was the strongest catalyst. It was further demonstrated that the oxidation reaction is inhibited by the adsorption of thiol species present in the system on copper particles. Combining copper with the iron (III) chloride-containing system also resulted in the inhibition of signal increase in the sulfoxide region of the spectra. The results of this preliminary research on the bitumen oxidation reaction presented are proposed for further research regarding control of aging of asphalt concrete, especially during the recycling works. 相似文献
10.
Composite Materials Based on Shape‐Memory Ti2NiCu Alloy for Frontier Micro‐ and Nanomechanical Applications 下载免费PDF全文