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101.
Abstract

On the subject of fuzzy set-based approximate reasoning, this paper attempts to present a perspective that is both rigorously stated and different from the standard approach as stated by Mamdani and many others. Functionally speaking, this alternative perspective produces results essentially the same as the standard one, and in fact we intend to prove that subject to certain assumptions the results will be exactly die same. We feel however that the alternative perspective offers advantages in that it makes a more appropriate and more understandable use of such concepts as fuzzy relations, the extension principle, and fuzzy composition. If indeed it can lead to a clearer and more widespread understanding of the approximate reasoning formalism then this could conceivably spark broader interest in fuzzy control and other applications.  相似文献   
102.
The potential of the natural chabazite for the selective catalytic reduction (SCR) of NOx with NH3 is evaluated in the present work. Activity tests were performed under technically relevant reaction and temperature conditions for the fresh and hydrothermally aged catalysts. The natural chabazite before and after alkaline removal as well as after iron and copper addition were compared. The structural as well as surface and bulk properties were elucidated by a variety of complementary characterization techniques, i.e. XRD, XPS, EPR, BET, NH3‐TPD, ex situ and in situ XAS. The results indicate that an important facet for using the natural chabazite for the standard and fast SCR reactions is the removal of alkaline metals, which at the same time also leads to a partial change of the structure and the size of the iron‐containing particles. The performance and especially the hydrothermal stability can be further improved by copper addition.  相似文献   
103.
This article describes 2 experiments about verb–argument relations in sentence processing in which there is no ambiguity involving the subcategorization of the verb but in which the role that the argument serves is initially unclear. Specifically, a self-paced reading experiment and an eye-tracking experiment investigated the way in which readers form unbounded dependencies when the verb is looking for both a direct object and a clause and when the filler either could be the direct object or could form part of the clause. The results suggested that readers treated the filler as the verb's direct object and probably also considered the clausal analysis at the same time. The results are interpreted with respect to current accounts of parsing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
Dey J  Tran RT  Shen J  Tang L  Yang J 《大分子材料与工程》2011,296(12):1149-1157
We have recently reported upon the development of crosslinked urethane-doped polyester (CUPE) network elastomers, which was motivated by the desire to overcome the drawbacks presented by crosslinked network polyesters and biodegradable polyurethanes for soft tissue engineering applications. Although the effect of the isocyanate content and post-polymerization conditions on the material structure-property relationship was examined in detail, the ability of the diol component to modulate the material properties was only studied briefly. Herein, we present a detailed report on the development of CUPE polymers synthesized using diols 4, 6, 8, 10, or 12 methylene units in length in order to investigate what role the diol component plays on the resulting material's physical properties, and assess their long-term biological performance in vivo. An increase in the diol length was shown to affect the physical properties of the CUPE polymers primarily through lowered polymeric crosslinking densities and elevated material hydrophobicity. The use of longer chain diols resulted in CUPE polymers with increased molecular weights resulting in higher tensile strength and elasticity, while also increasing the material hydrophobicity to lower bulk swelling and prolong the polymer degradation rates. Although the number of methylene units largely affected the physical properties of CUPE, the choice of diol did not affect the overall polymer cell/tissue-compatibility both in vitro and in vivo. In conclusion, we have established the diol component as an important parameter in controlling the structure-property relationship of the polymer in addition to diisocyanate concentration and post-polymerization conditions. Expanding the family of CUPE polymers increases the choices of biodegradable elastomers for tissue engineering applications.  相似文献   
105.
Two chemically modified phenolic resins (PFs) designed and developed for the matrix resins of organic friction materials were characterized. The braking performance of organic brake pads based on the two modified resins and reinforced with hybrid fibers was investigated on a full‐scale test bench. The results indicate that the modified PF with more internal friction units possessed much higher impact and compression strengths, greater toughness, and better braking stability. We concluded that the matrix resin with more adjustable structural units allowed for an adjustable Young's modulus and dynamic mechanical properties and, hence, could indirectly allow an adjustable friction coefficient for organic brake pads during braking process and, furthermore, enable the optimization of braking stability of the friction couples. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012  相似文献   
106.
We generate a sequence using the Newton–Kantorovich method in order to approximate a locally unique solution of an operator equation on a Banach space under Hölder continuity conditions. Using recurrence relations, Hölder as well as centre-Hölder continuity assumptions on the operator involved, we provide a semilocal convergence analysis with the following advantages over the elegant work by Hernánde? in (The Newton method for operators with Hölder continuous first derivative, J. Optim. Theory Appl. 109(3) (2001), pp. 631–648.) (under the same computational cost): finer error bounds on the distances involved, and a more precise information on the location of the solution. Our results also compare favourably with recent and relevant ones in (I.K. Argyros, Concerning the “terra incognita” between convergence regions of two Newton methods, Nonlinear Anal. 62 (2005), pp. 179–194; I.K. Argyros, Computational Theory of Iterative Methods, in Studies in Computational Mathematics, Vol. 15, C.K. Chui and L. Wuytack, eds., Elsevier Publ. Co., New York, USA, 2007; I.K. Argyros, On the gap between the semilocal convergence domain of two Newton methods, Appl. Math. 34(2) (2007), pp. 193–204; I.K. Argyros, On the convergence region of Newton's method under Hölder continuity conditions, submitted for publication; I.K. Argyros, Estimates on majorizing sequences in the Newton–Kantorovich method, submitted for publication; F. Cianciaruso and E. DePascale, Newton–Kantorovich approximations when the derivative is Hölderian: Old and new results, Numer. Funct. Anal. Optim. 24 (2003), pp. 713–723; F. Cianciaruso and E. DePascale, Estimates of majorizing sequences in the Newton–Kantorovich method, Numer. Funct. Anal. Optim. 27(5–6) (2006), pp. 529–538; F. Cianciaruso and E. DePascale, Estimates of majorizing sequences in the Newton–Kanorovich method: A further improvement, J. Math. Anal. Appl. 322 (2006), pp. 329–335; N.T. Demidovich, P.P. Zabreiko, and Ju.V. Lysenko, Some remarks on the Newton–Kantorovich mehtod for nonlinear equations with Hölder continuous linearizations, Izv. Akad. Nauk Belorus 3 (1993), pp. 22–26 (in Russian). (E. DePascale and P.P. Zabreiko, The convergence of the Newton–Kantorovich method under Vertgeim conditions, A new improvement, Z. Anal. Anwendvugen 17 (1998), pp. 271–280.) and (L.V. Kantorovich and G.P. Akilov, Functional Analysis in Normed Spaces, Pergamon Press, Oxford, 1982; J.V. Lysenko, Conditions for the convergence of the Newton–Kantorovich method for nonlinear equations with Hölder linearizations, Dokl. Akad. Nauk BSSR 38 (1994), pp. 20–24 (in Russian); B.A. Vertgeim, On some methods for the approximate solution of nonlinear functional equations in Banach spaces, Uspekhi Mat. Nauk 12 (1957), pp. 166–169 (in Russian); Amer. Math. Soc. Transl. 16 (1960), pp. 378–382. (English Trans.).)  相似文献   
107.
108.
In order to characterize the mechanical behavior of HDPE pipes, the ASTM D 2290-04 standard recommends carrying out tensile tests on notched rings, cut out from the pipe. This very simple test is also utilized to investigate the aging effect of the pipe by determining the strain at failure. Comparison between full ring and notched ring mechanical responses are discussed. Constitutive modeling including strain rate effects was performed by finite element analysis. This allowed a better understanding of the stress state in the cross section perpendicular to the loading direction. Additionally, the influence of a thin layer of oxidized HDPE in the inner wall of the ring was studied in the light of the finite element results.  相似文献   
109.
Decades of research demonstrate that conflict shapes and permeates a broad range of family processes. In the current article, we argue that greater insight, integration of knowledge, and empirical achievement in the study of family conflict can be realized by utilizing a powerful theory from evolutionary biology that is barely known within psychology: parent–offspring conflict theory (POCT). In the current article, we articulate POCT for psychological scientists, extend its scope by connecting it to the broader framework of life history theory, and draw out its implications for understanding conflict within human families. We specifically apply POCT to 2 instances of early mother–offspring interaction (prenatal conflict and weaning conflict); discuss the effects of genetic relatedness on behavioral conflict between parents, children, and their siblings; review the emerging literature on parent–offspring conflict over the choice of mates and spouses; and examine parent–offspring conflict from the perspective of imprinted genes. This review demonstrates the utility of POCT, not only for explaining what is known about conflict within families but also for generating novel hypotheses, suggesting new lines of research, and moving us toward the “big picture” by integrating across biological and psychological domains of knowledge. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
110.
网络信息的传播呈现覆盖面越来越广、速度越来越快、影响力越来越大、衍生信息越来越多的趋势。由于缺乏有效的法律法规来引导和规范网络环境,使信息传播不能完全做到客观、真实和完整。这些问题的存在,是对国有企业危机公关工作提出的新挑战。只有认真分析网络环境下国有企业面临的危机公关新特点,针对网络环境制定适宜的危机公关策略,才能将网络传播的速度和影响力转化为企业发展的契机和助力。  相似文献   
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