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481.
A new approach to constrained state estimation for discrete‐time linear systems with unknown inputs 下载免费PDF全文
Jose Fernando Garcia Tirado Alejandro Marquez‐Ruiz Hector Botero Castro Fabiola Angulo 《国际强度与非线性控制杂志
》2018,28(1):326-341
》2018,28(1):326-341
This paper addresses the problem of estimating the state for a class of uncertain discrete‐time linear systems with constraints by using an optimization‐based approach. The proposed scheme uses the moving horizon estimation philosophy together with the game theoretical approach to the filtering to obtain a robust filter with constraint handling. The used approach is constructive since the proposed moving horizon estimator (MHE) results from an approximation of a type of full information estimator for uncertain discrete‐time linear systems, named in short ‐MHE and –full information estimator, respectively. Sufficient conditions for the stability of the ‐MHE are discussed for a class of uncertain discrete‐time linear systems with constraints. Finally, since the ‐MHE needs the solution of a complex minimax optimization problem at each sampling time, we propose an approximation to relax the optimization problem and hence to obtain a feasible numerical solution of the proposed filter. Simulation results show the effectiveness of the robust filter proposed. 相似文献
482.
O'Donnell James P.; Stein Mark A.; Machabanski Hector; Cress Joseph N. 《Canadian Metallurgical Quarterly》1982,50(5):643
Compared the factor structure of a modified Behavior Problem Checklist for 208 Mexican-American (MA) and 208 Anglo-American 3–5 yr olds from low socioeconomic class families. Of the 5 factors extracted for each group, only the Anxiety-Withdrawal dimension exhibited strong cross-cultural similarity. Two other MA factors, Distractible-Hypoactive and Anxious-Negativism, were interpretable within the framework of MA culture. Results suggest that emergent classification systems should allow for cultural variation in symptom expression. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
483.
The basic building blocks for resonant tunneling diode (RTD) logic circuits are threshold gates (TGs) instead of the conventional Boolean gates (AND, OR, NAND, NOR) due to the fact that, when designing with RTDs, TGs can be implemented as efficiently as conventional ones, but realize more complex functions. Recently, RTD structures implementing multi-threshold threshold gates (MTTGs) have been proposed which further increase the functionality of the original TGs while maintaining their operating principle and allowing also the implementation of nanopipelining at the gate level. This paper describes the design of n-bit adders using these MTTGs. A comparison with a design based on TGs is carried out showing advantages in terms of power consumption and power delay product. 相似文献
484.
Biological evaluation and quantitative analysis of antioxidant compounds in pulps of the Amazonian fruits bacuri (Platonia insignis Mart.), ingá (Inga edulis Mart.), and uchi (Sacoglottis uchi Huber) by UHPLC‐ESI‐MS/MS 下载免费PDF全文
Flávio A. de Freitas Rafael C. Araújo Elzalina R. Soares Rita C. S. Nunomura Felipe M. A. da Silva Sarah R. S. da Silva Antonia Q. L. de Souza Afonso D. L. de Souza Francisco Franco‐Montalbán Leonard D. R. Acho Emerson S. Lima Giovana A. Bataglion Hector H. F. Koolen 《Journal of Food Biochemistry》2018,42(1)
Bacuri, ingá, and uchi are Amazon fruits consumed specially in the North region of Brazil. Due to their large consumption and the lack of knowledge regarding its chemical composition, these fruits were studied in relation to their Antioxidant chemical constitution. The total phenolic content ranged from 3.86 ± 0.47 to 33.38 ± 1.51 mg GAE/100 g, and the total flavonoid content ranged from 1.75 ± 0.22 to 19.44 ± 0.87 mg QUERE/100 g, where the contents showed a significant correlation with DPPH and ABTS antioxidant assays. Thus, UHPLC‐MS/MS was applied do quantify selected compounds, been citric acid the most abundant for all fruits. Furthermore, samples were screened for their α‐glycosidase and lipase inhibitory effects, in addition to their antimicrobial potentials. Bacuri showed the highest antioxidant and α‐glycosidase inhibitory capacity (IC50 15.20 μg/mL), whereas uchi and its main metabolite bergenin displayed moderate antimicrobial activities. The results shed light into the potentials of Amazonian fruit sources.
Practical applications
Plant phenolics are essential components of functional foods, due to their antioxidant and enzyme inhibition activities, which are directly linked to several diseases prevention. This is the first study about the quantification of antioxidant compounds in the Amazonian fruits: bacuri, ingá, and uchi. Although they are quite consumed in the North region of Brazil, there are no bio‐products made from them. This study aimed to elucidate the knowledge about the chemical composition and potentialities within these fruits with the practical purpose of highlighting them to future commercial applications. In addition, once we indicate their capabilities, we contribute with local populations in respect to the production of such fruits, which still is a family activity. 相似文献485.
The present study investigated the influence of air temperature on the drying kinetics, color, rehydration, total volatile basic nitrogen (TVBN), antioxidant capacity and texture of osmosed jumbo squid fillets during convective dehydration at 50, 60, 70, 80 and 90 °C. The Logarithmic and Two-term models could be used to describe the squid experimental drying curves. Discoloration of product was more noticeable at high drying temperatures where combined effects of non-enzymatic browning as well as protein denaturation modified the original color of the squid samples. Rehydration indexes showed a decrease while texture presented an increase with increasing air-drying temperature probably due to changes in food protein matrix. Total volatile basic nitrogen increased with process temperature. Antioxidant activity presented a decrease with temperature, especially at high drying temperatures. Results of this study demonstrated that the drying kinetics together with the reported quality attributes of the dried squid can be used to improve the final characteristics of the product. 相似文献
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Ponomaryov Volodymyr Montenegro Hector Rosales Alberto Duchen Gonzalo 《Journal of Real-Time Image Processing》2015,10(2):313-328
Journal of Real-Time Image Processing - A novel fuzzy 3D filter designed to suppress impulsive noise in color video sequences is proposed. In contrast to other state-of-the-art algorithms, the... 相似文献