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Fault diagnosis based on adaptive observer for a class of non-linear systems with unknown parameters
Bin Jiang Marcel Staroswiecki Vincent Cocquempot 《International journal of control》2013,86(4):367-383
In this paper, the fault diagnosis problem for a class of non-linear systems with uncertainty which depends on states, inputs and unknown constant parameters is discussed. Under some geometric conditions, the system is transformed into two different subsystems. One is not affected by actuator faults, so a non-linear adaptive observer can be designed based on the assumption of the strictly positive realness (SPR). The other whose states can be measured is affected by the faults. Actuator fault diagnosis is based on estimations of both the state and the unknown parameters with good accuracy. Discussions on release of SPR requirement and extension to the sensor fault case are also made. Finally, two examples are given in order to illustrate the applicability of the proposed methods for actuator fault diagnosis and sensor fault diagnosis respectively. 相似文献
23.
Marcel Wild 《Journal of Mathematical Imaging and Vision》2013,46(1):66-73
Many nonlinear filters used in practise are stack filters. An algorithm is presented which calculates the output distribution of an arbitrary stack filter S from the disjunctive normal form (DNF) of its underlying positive Boolean function (PBF). Our algorithm avoids to enumerate the models of the PBF one by one, and thus is considerably more efficient than previous methods. The so called rank selection probabilities can be computed along the way. 相似文献
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Zvolensky Michael J.; Marshall Erin C.; Johnson Kirsten; Hogan Julianna; Bernstein Amit; Bonn-Miller Marcel O. 《Canadian Metallurgical Quarterly》2009,17(1):31
The present investigation examines anxiety sensitivity, distress tolerance, and fear reactivity to bodily sensations in relation to Coping and Conformity marijuana use motives among a sample of young adult marijuana users (n = 135; 46.7% women; Mage = 20.45, SD = 5.0). After controlling for current marijuana use frequency (past 30 days), daily cigarette smoking rate, average volume of alcohol used over the past year, negative affectivity, and other marijuana use motives, anxiety sensitivity was significantly and uniquely associated with Coping and Conformity motives for marijuana use. Distress tolerance evidenced significant and unique incremental relations to Coping motives, whereas fear reactivity to bodily sensations was unrelated to any marijuana use motive. These results provide novel information related to the role of emotional sensitivity and tolerance factors as they pertain to specific types of motives for marijuana use among young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Wesley Pacheco Calixto A. Paulo Coimbra Jesus Carlos da Mota Marcel Wu Wander G. da Silva Bernardo Alvarenga Leonardo da Cunha Brito Aylton Jose Alves Elder Geraldo Domingues Daywes Pinheiro Neto 《International Journal of Numerical Modelling》2015,28(1):78-95
This work presents a genetic operator developed from mathematical methods of curve extrapolation applied in solving problems in geoelectrical prospection. This operator will assist the production of fitter individuals in the population of a genetic algorithm in which inherent patterns of the best individuals of each generation are recognized. The proposed operator in conjunction with a real‐coded genetic algorithm is compared to five alternative optimization techniques known and used in the application to problems in geoelectrical prospection. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
28.
A paradoxical situation exists where vernacular building traditions are in a state of decline and are being replaced by modern counterparts, but they are repeatedly cited in the academic literature as exemplary models of environmental practice. This paradox is examined through research on whether vernacular passive cooling systems in the hot and dry climates of present-day Iran are practicable for the provision of comfortable indoor temperatures. Investigating their technical thermal performance as well as user perceptions and behaviour, positive and negative attributes of the cooling systems are identified. If conclusions about the long-term viability of vernacular buildings are to be drawn, then social, cultural, economic and environmental attributes need to be taken into consideration. Despite rather widespread and persistent assumptions, vernacular building traditions are not necessarily able to survive and the choices made by local people regarding the continuation or abandonment of specific traditions are influenced by a variety of cultural and practical factors. This substantiates the necessity of an integrated and holistic approach that engages with these variables in order to acquire a better understanding of the conditions for the survival of vernacular traditions. Le fait que les traditions architecturales vernaculaires se trouvent dans un état de déclin et sont remplacées par leurs équivalents modernes, alors même qu'elles sont citées à maintes reprises dans la littérature universitaire comme des modèles exemplaires de pratique environnementale, constitue une situation paradoxale. Ce paradoxe est étudié au travers de recherches visant à déterminer si les systèmes de refroidissement passif vernaculaires sous les climats chauds et secs de l'Iran d'aujourd'hui peuvent être mis en pratique pour assurer des températures intérieures confortables. L’étude de leurs performances thermiques techniques aussi bien que des perceptions et du comportement des utilisateurs permet d'identifier les attributs positifs et négatifs des systèmes de refroidissement. S'il faut tirer des conclusions concernant la viabilité à long terme des bâtiments vernaculaires, il est alors nécessaire de prendre en considération les attributs sociaux, culturels, économiques et environnementaux. En dépit de présomptions plutôt répandues et tenaces, les traditions architecturales vernaculaires ne sont pas nécessairement capables de survivre et les choix opérés par les populations locales quant à la poursuite ou l'abandon de traditions spécifiques sont influencés par divers facteurs culturels et pratiques. Ceci confirme la nécessité d'une approche intégrée et holistique qui, par ces variables, incite à acquérir une meilleure compréhension des conditions propres à assurer la survie des traditions vernaculaires. Mots clés: confort adaptatif, performances des bâtiments, attentes, traditions locales, occupants, refroidissement passif, architecture vernaculaire, Iran 相似文献
29.
Structure–Activity Relationships of JMV4463, a Vectorized Cathepsin D Inhibitor with Antiproliferative Properties: The Unique Role of the AMPA‐Based Vector 下载免费PDF全文
Dr. Lubomir L. Vezenkov Clément A. Sanchez Dr. Virginie Bellet Dr. Vincent Martin Dr. Marie Maynadier Dr. Nadir Bettache Prof. Vincent Lisowski Prof. Jean Martinez Dr. Marcel Garcia Dr. Muriel Amblard Dr. Jean‐François Hernandez 《ChemMedChem》2016,11(3):302-308
Cathepsin D (CathD) is overexpressed and secreted by several solid tumors and stimulates their growth, the mechanism of which is still not understood. In this context, the pepstatin bioconjugate JMV4463 [Ac‐arg‐O2Oc‐(Val)3‐Sta‐Ala‐Sta‐(AMPA)4‐NH2; O2Oc=8‐amino‐3,6‐dioxaoctanoyl, Sta=statine, AMPA=ortho‐aminomethylphenylacetyl], containing a new kind of cell‐penetrating vector, was previously shown to exhibit potent antiproliferative effects in vitro and to delay the onset of tumors in vivo. In this study, we performed a structure–activity relationship analysis to evaluate the significance of the inhibitor and vector moieties of JMV4463. By modifying both statine residues of pepstatin we found that the antiproliferative activity is correlated with CathD inhibition, supporting a major role of the catalytic activity of intracellular CathD in cancer cell proliferation. Replacing the vector composed of four AMPA units with other vectors was found to abolish cytotoxicity, although all of the conjugates enabled pepstatin transport into cells. In addition, the AMPA4 vector must be localized at the C terminus of the bioconjugate. The unexpected importance of the vector structure and position for cytotoxic action suggests that AMPA4 enables pepstatin to inhibit the proteolysis of critical CathD substrates involved in cell proliferation via a unique mechanism of action. 相似文献
30.
Marcel Richter Yuriy Zakrevskyy Michael Eisele Nino Lomadze Svetlana Santer Regine v. Klitzing 《Polymer》2014
The contraction/swelling transition of anionic PNIPAM-co-AAA particles can be manipulated by light using interactions with cationic azobenzene-containing surfactant. In this study the influence of pH-buffers and their concentrations, the charge density (AAA content) in microgel particles as well as the spacer length of the surfactant on the complex formation between the microgel and surfactant is investigated. It is shown that the presence of pH buffer can lead to complete blocking of the interactions in such complexes and the resulting microgel contraction/swelling response. There is a clear competition between the buffer ions and the surfactant molecules interacting with microgel particles. When working in pure water solutions with fixed concentration (charge density) of microgel, the contraction/swelling of the particles is controlled only by relative concentration (charge ratio) of the surfactant and AAA groups of the microgel. Furthermore, the particle contraction is more efficient for shorter spacer length of the surfactant. The onset point of the contraction process is not affected by the surfactant hydrophobicity. This work provides new insight into the interaction between microgel particles and photo-sensitive surfactants, which offers high potential in new sensor systems. 相似文献