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231.
Jesus Gonzalez-Trejo Jose Alvarez Ramirez Guillermo Fernandez 《Journal of Process Control》1999,9(3):221-231
The goal of this paper is to describe a linearizing feedback adaptive control structure which leads to a high quality regulation of the output error in the presence of uncertainties and external disturbances. The controller consists of three elements: a nominal input–output linearizing compensator, a state observer and an uncertainty estimator, which provides the adaptive part of the control structure. In this way, the feedback controller, based on the disturbance observer, compensates for external disturbances and plant uncertainties. The effectiveness of the controller is demonstrated on a distillation column via numerical simulations. © 相似文献
232.
The developmental expression of salivary glycoconjugates was investigated in the rat submandibular and sublingual glands by conventional and lectin histochemistry. By the time of the first differentiation of secretory structures, in spite of similar morphological features, a different histochemical reactivity was detected, accounting for a relevant content of neutral glycoconjugates in the submandibular gland and the occurrence of both neutral and acidic glycoconjugates in the sublingual one. The use of lectins allowed the main changes of secretory components to be noted around gestational day 18. DBA and WGA lectins seemed to act as pre- and post-natal development markers while Con A lectin was indicative of post-natal differentiation. Taken together, data from lectin histochemistry indicated the transitional occurrence of glycoconjugates, probably involved in temporally restricted functions, as well as the co-existence of different secretory components that might also reflect maturational changes of single products. 相似文献
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234.
Di Pasquale F. Hui Fang Deng Anibal Fernandez F. Day S.E. Davies J.B. Johnson M.T. van der Put A.A. van de Eerenbeemd J.M.A. van Haaren J.A.M.M. Chapman J.A. 《Electron Devices, IEEE Transactions on》1999,46(4):661-668
In this paper a two-dimensional (2-D) dynamic model, based on a tensor formulation and solved numerically by combining finite elements and finite differences, is proposed and used for analyzing nematic liquid crystal (LC) test cells with interdigital electrodes. We compare theoretical and experimental results concerning the switching behavior, response mechanism, and viewing angle characteristics of nematic LC pixel structures which use the in-plane-switching (IPS) mode. The good agreement observed between theory and experiment in terms of electro-optical properties validates our modeling and demonstrates its potential for design optimization. We show that the proposed LC test cells, using the in-plane-switching mode, ensure switching-ON and -OFF response times of 22 and 28 ms, respectively, and excellent viewing angle characteristics 相似文献
235.
X Fernandez J Mourot B Lebret S Gilbert G Monin 《Journal of the science of food and agriculture》2000,80(6):705-710
The present study is part of a project which aims to examine the influence of intramuscular fat (IMF) content on the sensory attributes and consumer acceptability of pork. An experiment was conducted to evaluate the influence of IMF level in muscle semimembranosus (SM) on the composition of its lipid fraction and on the sensory qualities and consumer acceptability of cured cooked hams. Thirty‐two carcasses were selected 24 h after slaughter from 125 Duroc × Landrace castrated male pigs showing large variability in SM muscle IMF content and were assigned to four IMF groups: ≤2%, 2–3%, 3–4% and >4%. Cured cooked ham slices were evaluated by a trained expert panel of 12 members and by a group of 56 consumers. Results from lipid analyses indicate that (i) an increase in IMF content was almost entirely reflected by an increase in the triglyceride content of the muscle and (ii) higher IMF levels were associated with higher free fatty acid and monoglyceride and lower cholesterol levels. The sensory evaluation of marbling significantly increased with IMF level, whereas other sensory qualities were unaffected. High IMF levels significantly depreciated the consumer perception of fat, aspect, taste and smell of ham slices. Overall, slices with the highest IMF levels got the least favourable rating by consumers. The present study indicates that increased IMF levels in muscle semimembranosus do not have significant effects on the sensory attributes of cured cooked hams, apart from the perception of marbling. However, high IMF levels have detrimental effects on the acceptability by consumers. © 2000 Society of Chemical Industry 相似文献
236.
Critical review on improved electrochemical impedance spectroscopy-cuckoo search-Elman neural network modeling methods for whole-life-cycle health state estimation of lithium-ion battery energy storage systems
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Ran Xiong Shunli Wang Paul Takyi-Aninakw Siyu Jin Member IEEE Carlos Fernandez Qi Huang Fellow IEEE Weihao Hu Senior Member IEEE Wei Zhan 《电力系统保护与控制》2024,9(2):75-100
Efficient and accurate health state estimation is crucial for lithium-ion battery (LIB) performance monitoring and economic evaluation. Effectively estimating the health state of LIBs online is the key but is also the most difficult task for energy storage systems. With high adaptability and applicability advantages, battery health state estimation based on data-driven techniques has attracted extensive attention from researchers around the world. Artificial neural network (ANN)-based methods are often used for state estimations of LIBs. As one of the ANN methods, the Elman neural network (ENN) model has been improved to estimate the battery state more efficiently and accurately. In this paper, an improved ENN estimation method based on electrochemical impedance spectroscopy (EIS) and cuckoo search (CS) is established as the EIS-CS-ENN model to estimate the health state of LIBs. Also, the paper conducts a critical review of various ANN models against the EIS-CS-ENN model. This demonstrates that the EIS-CS-ENN model outperforms other models. The review also proves that, under the same conditions, selecting appropriate health indicators (HIs) according to the mathematical modeling ability and state requirements are the keys in estimating the health state efficiently. In the calculation process, several evaluation indicators are adopted to analyze and compare the modeling accuracy with other existing methods. Through the analysis of the evaluation results and the selection of HIs, conclusions and suggestions are put forward. Also, the robustness of the EIS-CS-ENN model for the health state estimation of LIBs is verified. 相似文献
237.
This article describes the results of an analysis of the assimilation of ergonomic knowledge by nonergonomists during participatory ergonomics projects whose aim is the prevention of work-related musculoskeletal disorders (WMSDs). In two plants producing electrical consumer products and telecommunications equipment, ergonomic groups were established and trained. The groups analyzed seven working situations resulting in 50 implemented proposals. A reduction in WMSD risk factors was observed. The analysis of the assimilation of ergonomic knowledge by the groups and their members was based on two sources: analysis of the groups' working sessions, and independent interviews of group members. The results show that group members master most phases of the formalized ergonomic analysis. The interviews revealed that several factors influence knowledge transfer: prior training and organizational status of the group members, the didactic method used, company culture, support by management, and attitudes of coworkers. © 1997 John Wiley & Sons, Inc. 相似文献
238.
Bibian M. E. Tullemans Alicia Veninga Delia I. Fernandez Maureen J. B. Aarts Johannes A. Eble Paola E. J. van der Meijden Johan W. M. Heemskerk Marijke J. E. Kuijpers 《International journal of molecular sciences》2021,22(20)
Current antiplatelet drugs for the treatment of arterial thrombosis often coincide with increased bleeding risk. Several tyrosine kinase inhibitors (TKIs) for cancer treatment inhibit platelet function, with minor reported bleeding symptoms. The aim of this study was to compare the antiplatelet properties of eight TKIs to explore their possible repurposing as antiplatelet drugs. Samples of whole blood, platelet-rich plasma (PRP), or isolated platelets from healthy donors were treated with TKI or the vehicle. Measurements of platelet aggregation, activation, intracellular calcium mobilization, and whole-blood thrombus formation under flow were performed. Dasatinib and sunitinib dose-dependently reduced collagen-induced aggregation in PRP and washed platelets; pazopanib, cabozantinib, and vatalanib inhibited this response in washed platelets only; and fostamatinib, axitinib, and lapatinib showed no/limited effects. Fostamatinib reduced thrombus formation by approximately 50% on collagen and other substrates. Pazopanib, sunitinib, dasatinib, axitinib, and vatalanib mildly reduced thrombus formation on collagen by 10–50%. Intracellular calcium responses in isolated platelets were inhibited by dasatinib (>90%), fostamatinib (57%), sunitinib (77%), and pazopanib (82%). Upon glycoprotein-VI receptor stimulation, fostamatinib, cabozantinib, and vatalanib decreased highly activated platelet populations by approximately 15%, while increasing resting populations by 39%. In conclusion, the TKIs with the highest affinities for platelet-expressed molecular targets most strongly inhibited platelet functions. Dasatinib, fostamatinib, sunitinib, and pazopanib interfered in early collagen receptor-induced molecular-signaling compared with cabozantinib and vatalanib. Fostamatinib, sunitinib, pazopanib, and vatalanib may be promising for future evaluation as antiplatelet drugs. 相似文献
239.
240.
Antimicrobial packaging based on ɛ‐polylysine bioactive film for the control of mycotoxigenic fungi in vitro and in bread
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C. Luz J. Calpe F. Saladino Fernando B. Luciano M. Fernandez‐Franzón J. Mañes G. Meca 《Journal of Food Processing and Preservation》2018,42(1)
?‐Poly‐l‐ lysine (?‐PL) is a cationic peptide with a broad‐spectrum antimicrobial activity. This study investigates the use of ?‐PL as natural antimicrobial to inhibit fungal growth and to reduce aflatoxins (AFs) production. Antifungal activity of starch biofilms with different concentrations of ?‐Poly‐l‐ lysine (?‐PL) was determined in solid medium against Aspergillus parasiticus (AFs producer) and Penicillium expansum. Then, biofilms were tested as antimicrobial devices for the preservation of bread loaf inoculated with A. parasiticus CECT 2681 and P. expansum CECT 2278. Shelf life and AFs content were examined. Biofilms with concentrations of ?‐PL less than 1.6 mg/cm2 showed no fungal growth inhibition in solid medium, while the antifungal activity of the films with greater than 1.6 mg/cm2 of ?‐PL was dose dependent. The shelf life of bread inoculated with A. parasiticus was increased by 1 day with the use of films containing 1.6–6.5 mg ?‐PL/cm2, while shelf life of bread tainted with P. expansum was increased by 3 day with 6.5 mg ?‐PL/cm2. AFs production was greatly inhibited by ?‐PL biofilms (93–100%). Thus, ?‐PL biofilms could be potentially used as antimicrobial device during bread storage as a natural alternative to the synthetic preservatives.