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FIXED POINTS FOR WEAKLY INWARD MAPPINGS IN BANACH SPACES (Ⅱ)
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作者 Shaoyuan Xu Wangbin Xu Guanghui Zhou 《Analysis in Theory and Applications》 2010年第4期308-319,共12页
S. Hu and Y. Sun[1] defined the fixed point index for weakly inward mappings, investigated its properties and studied fixed points for such mappings. In this paper, following S. Hu and Y. Sun, we further investigate b... S. Hu and Y. Sun[1] defined the fixed point index for weakly inward mappings, investigated its properties and studied fixed points for such mappings. In this paper, following S. Hu and Y. Sun, we further investigate boundary conditions, under which the fixed point index for i(A, Ω, p) is equal to nonzero, where i(A, Ω, p) is the completely continuous and weakly inward mapping. Correspondingly, we can obtain many new fixed point theorems of the completely continuous and weakly inward mapping, which generalize some famous theorems such as Rothe's theorem, Altman's theorem, Petryshyn's theorem etc. in the case of weakly inward mappings. In addition, our conclusions extend the famous fixed point theorem of cone expansion and compression to the case of weakly inward mappings. Moreover, the main results contain and generalize the corresponding results in the recent work[2]. 展开更多
关键词 fixed point and fixed point index weakly inward mapping completely contin-uous operator real Banach space cone
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Applicability of the Arrhenius model for Ammonia Oxidizing Bacteria subjected to temperature time gradients 被引量:2
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作者 Alberto MANNUCCI Giulio MUNZ +2 位作者 Gualtiero MORI Claudio LUBELLO Jan A. OLESZKIEWICZ 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2015年第6期988-994,共7页
The aim of this work is to identify the range of applicability of Arrhenius type temperature dependence for Ammonia Oxidizing Bacteria (AOB) subjected to tem- perature time gradients through continuous titrimetric t... The aim of this work is to identify the range of applicability of Arrhenius type temperature dependence for Ammonia Oxidizing Bacteria (AOB) subjected to tem- perature time gradients through continuous titrimetric tests. An innovative online differential titrimetric technique was used to continuously monitor the maximum biologic ammonia oxidation rate of the biomass selected in a pilot scale membrane bioreactor, as a function of temperature time gradients. The monitoring technique is based on the measurement of alkalinity and hydrogen peroxide con- sumption rates in two parallel reactors operated in non- limiting substrate conditions for AOB; both reactors were continuously fed with mixed liquor and in one of them AOB were inhibited with allylthiourea. The effects of temperature decrease rates in the range 1 to 4℃h^-1 were evaluated by controlling the titrimetric reactor in the temperature range 10℃-20℃. The dependence of growth kinetics on temperature time gradients and the range of applicability of Arrhenius model for temperature depen- dency of AOB growth kinetics were assessed. The Arrhenius model was found to be accurate only with temperature gradients lower than 2℃·h^-1. The estimated Arrhenius coefficients (θ) were shown to increase from 1.07 to 1.6 when the temperature decrease rate reached 4℃.h^-1. 展开更多
关键词 nitrification rate temperature effect contin-uous tilrimetric tests time-gradient temperature variations Ammonia Oxidizing Bacteria (AOB)
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Robust switched fractional controller for performance improvement of single phase active power filter under unbalanced conditions
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作者 H. AFGHOUL F. KRIM +1 位作者 D. CHIKOUCHE A. BEDDAR 《Frontiers in Energy》 SCIE CSCD 2016年第2期203-212,共10页
A novel controller is proposed to regulate the DC-link voltage of a single phase active power filter (SPAPF). The proposed switched fractional controller (SFC) consists of a conventional PI controller, a fractiona... A novel controller is proposed to regulate the DC-link voltage of a single phase active power filter (SPAPF). The proposed switched fractional controller (SFC) consists of a conventional PI controller, a fractional order PI (FO-PI) controller and a decision maker that switches between them. Commonly, the conventional PI controller is used in regulation loops due to its advantages in steady-state but it is limited in transient state. On the other hand, the FO-PI controller overcomes these draw- backs but it causes dramatic degradation in control performances in steady-state because of the fractional calculus theory and the approximation method used to implement this kind of controller. Thus, the purpose of this paper is to switch to the PI controller in steady-state to obtain the best power quality and to switch to the FO-PI controller when external disturbances are detected to guarantee a fast transient state. To investigate the efficiency and accuracy of the SFC considering all robustness tests, an experimental setup has been established. The results of the SFC fulfill the requirements, confirm its high performances in steady and transient states and demon- strate its feasibility and effectiveness. The experiment results have satisfied the limit specified by the IEEE harmonic standard 519. 展开更多
关键词 conventional PI controller fractional calculus(FC) total harmonic distortion (THD) Oustaloup contin-uous approximation (OCA) single phase active power filter(SPAPF)
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