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71.
72.
Interpreting and extracting fuzzy decision rules from fuzzy information systems and their inference 总被引:1,自引:0,他引:1
Information systems, which contain only crisp data, precise and unique attribute values for all objects, have been widely investigated. Due to the fact that in realworld applications imprecise data are abundant, uncertainty is inherent in real information systems. In this paper, information systems are called fuzzy information systems, and formalized by (objects; attributes; f), in which f is a fuzzy set and expresses some uncertainty between an object and its attribute values. To interpret and extract fuzzy decision rules from fuzzy information systems, the meta-theory based on modal logic proposed by Resconi et al. is modified. The modified meta-theory not only expresses uncertainty between objects and their attributes, but also uncertainty in the process of recognizing fuzzy information systems. In addition, according to perception computing (proposed by Zadeh), granules of fuzzy information systems can be represented by fuzzy decision rules, so that, fuzzy inference methods can be used to obtain the decision attribute of a new object. Finally, a novel way of combining evidences based on the modified meta-theory is introduced, which extends the concept of combining evidences based on Dempster-Shafer theory. 相似文献
73.
Maurizio Canetti Alberto Seves Laura Bergamasco Germano Munaretto Pier Luigi Beltrame 《应用聚合物科学杂志》1998,68(11):1877-1882
Ternary blends containing polypropylene, poly(1-butene), and hydrogenated oligo(cyclopentadiene) have been studied using microscopic, calorimetric, and X-ray diffraction techniques. While no phase separation was found to occur in the melt for all the considered compositions, demixing phenomena were observed by scanning electron microscopy in the ternary blends after crystallization of both polyolefins. On the other hand, a homogeneous surface without the presence of separate domains was observed for blends quenched avoiding the crystallization of polypropylene. The composition has been found to affect the crystallization and the melting properties of the ternary blends and the crystal modification of polypropylene. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1878–1882, 1998 相似文献
74.
Yang Song Chengqun Huang Jon Sin Juliana de F. Germano David J. R. Taylor Reetu Thakur Roberta A. Gottlieb Robert M. Mentzer Jr. Allen M. Andres 《International journal of molecular sciences》2022,23(1)
Sodium–glucose cotransporter 2 (SGLT2) inhibitors such as empagliflozin are known to reduce the risk of hospitalizations related to heart failure irrespective of diabetic state. Meanwhile, adverse cardiac remodeling remains the leading cause of heart failure and death in the USA. Thus, understanding the mechanisms that are responsible for the beneficial effects of SGLT2 inhibitors is of the utmost relevance and importance. Our previous work illustrated a connection between adverse cardiac remodeling and the regulation of mitochondrial turnover and cellular energetics using a short-acting glucagon-like peptide-1 receptor agonist (GLP1Ra). Here, we sought to determine if the mechanism of the SGLT2 inhibitor empagliflozin (EMPA) in ameliorating adverse remodeling was similar and/or to identify what differences exist, if any. To this end, we administered permanent coronary artery ligation to induce adverse remodeling in wild-type and Parkin knockout mice and examined the progression of adverse cardiac remodeling with or without EMPA treatment over time. Like GLP1Ra, we found that EMPA affords a robust attenuation of PCAL-induced adverse remodeling. Interestingly, unlike the GLP1Ra, EMPA does not require Parkin to improve/maintain mitochondria-related cellular energetics and afford its benefits against developing adverse remodeling. These findings suggests that further investigation of EMPA is warranted as a potential path for developing therapy against adverse cardiac remodeling for patients that may have Parkin and/or mitophagy-related deficiencies. 相似文献
75.
Lara PC Fabrino HJ Germano A Silva JB 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2012,29(4):609-616
A method for the determination of As, Cd and Pb in bovine, equine and poultry liver by ICP-MS was developed and validated. Samples were digested in a microwave oven using a 10% HNO(3) solution. A set of experiments was made according to a central composite design (CCD) for optimisation of the plasma argon flow, nebuliser argon flow and radiofrequency power applied to the plasma. During the validation, Rh and Ru were evaluated as internal standards and, after validation, the best was Rh for Pb and Cd analysis, but for As better results were obtained without an internal standard. The method allowed As, Cd and Pb determination with a 3.3% HNO(3) solution for the calibration curves ranging from 0 to 40 μg l(-1) for As and from 0 to 20 μg l(-1) for Cd and Pb. The recovery values obtained showed averages of 100%, 106% and 96% for As, Cd and Pb, respectively. Limits of quantification obtained were 85 μg kg(-1) for As, 6.5 μg kg(-1) for Cd and 12.5 μg kg(-1) for Pb. Repeatability and within-laboratory reproducibility were evaluated through the indicators HORRAT(r) and HORRAT(R), and the results were less than 0.30. The method is simple, fast and showed adequate precision and accuracy for the determination of As, Cd and Pb in bovine, equine and poultry liver. The precision, recovery, uncertainties, and limits of detection and quantification for each analyte were in accordance to European Union Commission Regulation 2007/333/EC. 相似文献
76.
Thermally induced chemical evolution in polyimide films investigated by X‐ray photoelectron spectroscopy 下载免费PDF全文
Liliane C. Battirola Petra Rudolf Germano Tremiliosi‐Filho Ubirajara P. Rodrigues‐Filho 《Polymer Engineering and Science》2018,58(6):943-951
Thermally modified polyimide films based on 1,4‐Phenylene diamine (p‐PDA) and 3,3′,4,4′ – Benzophenone tetracarboxylic dianhydride (BTDA) were prepared and their chemical structure transformation after thermal treatment at 350 °C–500 °C was investigated. X‐ray diffraction results revealed an increase in the polymer chain order for all treated PI samples as a consequence of the thermal treatment and chain interaction. TGA analysis showed that the heat treatment promoted different thermal degradation profiles. Electron spin resonance evidenced a large population of free radicals as a result of homogeneous bond cleavage when the thermal treatment was performed at 500 °C. X‐ray photoelectron spectroscopy analysis indicated that the chemical structure transformation not only occurs on the outer surface but also in the sub‐surface layer. These results show that controlled fast thermal treatment can produce materials with specific characteristics and may serve as a general strategy for changing both structural and chemical properties of the polymers. POLYM. ENG. SCI., 58:943–951, 2018. © 2017 Society of Plastics Engineers 相似文献
77.
78.
Caira S Ferranti P Gatti M Fornasari ME Barone F Lilla S Mucchetti G Picariello G Chianese L Neviani E Addeo F 《The Journal of dairy research》2003,70(3):315-325
Four Lactobacillus helveticus strains were studied for proteolytic capacity and general aminopeptidase (AP) and X-Pro dipeptidyl aminopeptidase (DAP) activity. The rate of hydrolysis and the activity against synthetic substrates with N-terminal residues of Arg, Lys, Leu, Glu or Pro, varied markedly among the strains. The X-Pro DAP activity was consistently high. The crude cell-wall and cytoplasm extracts from strain Lb. helveticus ISLC59 were analysed thoroughly for their proteolysis ability by using four synthetic peptide substrates, including alpha(s)1-CN(f1-23). Peptides formed during in vitro hydrolysis of the synthetic substrates by cell wall and cytoplasm preparations were identified by LC-ESI/MS. In doing so, it was possible to infer a prevalent endopeptidase activity splitting Lys7-His8 and Gln13-Glu14 bonds in the cytoplasm, and to deduce a secondary activity, which hydrolysed Glu14-Val15, Leu16-Asn17, Glu18-Asn19 and Lys3-His4 bonds lacking in the cell-wall. The presence of exopeptidases, as mainly AP, DAP, and carboxypeptidase (CPase) was deduced from the formation of several N- and C-terminally truncated peptides sets. The AP activity was higher in the cell-wall layer, where CPase activity was absent. The in vitro assays with cell extracts of the Lb. helveticus ISLC59 strain revealed extensive exopeptidase and endopeptidase activities. In several cases, the hydrolytic system of Lb. helveticus that splits in vitro alpha(s)1-CN(f1-23) peptide bonds was similar to that of Lactococcus lactis. The effects were also compared with those occurring in vivo in hard cheese such as Grana Padano. 相似文献
79.
The current restructuring of the U.S. health care delivery system is driven primarily by economic forces. Although primary care providers may understand the roles of technology and advocacy in fostering fundamental change, they may not be familiar with the issues related to financing of health care and, thus, may not fully appreciate the extent to which economic factors influence the character of their professional lives and the services they provide. Analysis of the loss of the home birth option in the 1950s provides a method for understanding and influencing the factors driving health care restructuring today. In examining short-stay delivery in the 1990s, this article also addresses ways in which managed health care systems may improve or restrict women's access to a variety of primary care services. 相似文献
80.
Senderowicz D. Nicollini G. Pernici S. Nagari A. Confalonieri P. Dallavalle C. 《Solid-State Circuits, IEEE Journal of》1997,32(12):1907-1919
An obvious way of achieving higher signal-to-noise ratio in oversampled data converters is by increasing the effective sampling rate. If all other components are kept constant, this translates into integrators with larger bandwidth that in turn results in higher overall power consumption. This work introduces the fully floating switched-capacitor configuration as a simple and robust technique to effectively double the sampling rate of oversampled data converters without compromising any aspect of the performance and yet maintaining the power levels of the conventional approach. The use of internal decimation in the switched-capacitor ladder structure of the digital-to-analog converter further helps in achieving the power budget goals. These converters have been implemented with circuitry capable of operating at a minimum supply voltage of 1.8 V under worst case process and temperature conditions and using clock bootstrapping for the transfer gates. The bootstrapping circuit described here uses a single internal capacitor and has functionality that limits the maximum clock voltage to safe levels under a wide range of supply voltages. The prototype was fabricated in a 0.5-μm CMOS double-poly technology. The analog-to-digital converter occupies a die area of 0.11 mm2 dissipating 550 μW while the digital-to-analog converter occupies 0.28 mm2 dissipating 600 μW 相似文献