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141.
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Some ideas relevant to the prevailing viscoelasticity interpretations of dynamic mechanical thermal analysis (DMTA) experiments
are presented. The main aspect is the inclusion of kinetic energy and inertia as variables, seeing the relaxing mass constantly
increasing during strain, assigning inertial variation and not viscosity to energy dissipation. The equations developed make
it possible to obtain the values of important viscoelastic properties, under in any experimental condition, with the data
taken from previous experiments. 相似文献
144.
The Helium Cooled Lithium Lead (HCLL) blanket is one of the two blanket concepts selected by the European Union to be tested in ITER. It is based on the use of Eurofer as structural material, helium as coolant and eutectic lithium–lead as breeder/neutron multiplier material. The design of the corresponding Test Blanket Module (TBM) for ITER has undergone several revisions in the last years. This paper presents an alternative cooling scheme for the HCLL-TBM, where the First Wall (FW) is cooled by vertical (poloidal) instead of horizontal (toroidal) channels. New Finite Element models have been developed and thermal and thermo-hydraulical analyses of the new design have been performed. Results show that the new cooling scheme presents several advantages with respect to the previous one: (i) the total number of cooling channels in the FW can be reduced; (ii) the overall pressure drops in one cooling channel are lower; (iii) the temperature profile in the breeding zone is more uniform. 相似文献
145.
Trautwein Ulrich; Lüdtke Oliver; Marsh Herbert W.; Nagy Gabriel 《Canadian Metallurgical Quarterly》2009,101(4):853
Results from prior research indicate that a student’s academic self-concept is negatively influenced by the achievement of others in his or her school (a frame of reference effect) and that this negative frame of reference effect is not or only slightly reduced by the quality, standing, or prestige of the track or school attended (a “reflected glory” effect). Going beyond prior studies, the present research used both between-school and within-school approaches to investigate frame of reference and reflected glory effects in education, incorporating students’ own perceptions of the standing of their school and class. Multilevel analyses were performed with data from 3 large-scale assessments with 4,810, 1,502, and 4,247 students, respectively. Findings from all 3 studies showed that, given comparable individual achievement, placement in high-achieving learning groups was associated with comparatively low academic self-concepts. However, students’ academic self-concept was not merely a reflection of their relative position within the class but also substantively associated with their individual and shared perceptions of the class’s standing. Moreover, the negative effects of being placed in high-achieving learning groups were weaker for high-achieving students. Overall, the studies support both educational and social psychology theorizing on social comparison. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
Dianini Hüttner Kringel Gabriel da Silva Filipini Myriam de las Mercedes Salas‐Mellado 《International Journal of Food Science & Technology》2017,52(5):1291-1298
The chemical modification of rice flour by phosphorylation is an alternative to improve the technological quality of bakery products. The aim of this study was to investigate the effect of phosphorylation process of rice flour on technological properties (specific volume, crumb and crust colour) of gluten‐free breads and the hardening of these breads during two storage temperatures (21 °C and ?24 °C). Breads were made with native rice flour, with phosphorylated rice flour and with wheat flour, used as control. The phosphorylation causes significant reduction in the synaeresis of pastes and in retrogradation tendency of rice flours, varying from 258.7 cP (native rice flour) to 122 cP (phosphorylated rice flour). The breads prepared with phosphorylated rice flour showed reduction in the hardness in both storage temperatures studied and effect on rice bread volume, crumb appearance and colour, demonstrating the possibility of use of the phosphorylated rice flour in gluten‐free breads. 相似文献
147.
Steven A. Gabriel 《Optimization and Engineering》2017,18(3):631-658
In this paper we present a novel formulation based on a median function to solve discretely constrained mixed complementarity problems (MCPs). Such problems seek to combine integer (discrete) solutions that are also equilibrium ones and have applications in engineering and economics. Several theoretical results show the correspondence between the easier-to-solve formulations presented and the original discretely constrained MCP. Lastly, the approach is successfully tested on a variety of illustrative examples. 相似文献
148.
Juan Gabriel Brida Marta Disegna Linda Osti 《Expert systems with applications》2012,39(13):11349-11356
Considering the importance of market segmentation as a marketing tool to determine promotional policies, this paper aims to contribute to the tourism literature using the two-level approach proposed by Vesanto and Alhoniemi (2000) as an alternative and effective method to conduct cluster analyses.For this purpose, an empirical study was conducted interviewing tourists who visited three different Christmas Markets in Northern Italy. The two-level approach is based on two clustering techniques used in sequence: a Self-Organizing Map (SOM) followed by a clustering algorithm. The Silhouette index (Rousseeuw, 1987) is used as a guideline during the second level in the selection process of both the best clustering techniques (between hierarchical and non-hierarchical) and the best partition.The analysis identified three cluster segments and this paper demonstrates the suitability of the clustering method adopted. In the discussion of the results, marketing and managerial implications are also highlighted. 相似文献
149.
Gabriel Henrique Horta de Oliveira Paulo Cesar Corrêa Emílio de Souza Santos Pedro Casanova Treto Mayra Darliane Martins Silva Diniz 《International Journal of Food Science & Technology》2011,46(10):2077-2084
The desorption isotherms and thermodynamic properties of cocoa beans were obtained during the drying process of this product. The isotherms were determined by dynamic method for various temperature (25, 35, 45 and 55 °C) and relative humidity (RH) conditions (30, 40, 50, 60, 70 and 80%). Equilibrium moisture content data were correlated by the Guggenheim–Anderson–de Boer (GAB) model, which presented good fit to the data, according to statistical procedures. Equilibrium moisture content ranged from 5.90 to 16.67 d.b.; it increased with an increment in the RH and decreased with increased temperature at a constant RH. Enthalpy values for each model coefficient were encountered, ranging from ?90.05 to 545.96 kJ kg?1. The integral isosteric heat of desorption and differential entropy increased with decreased equilibrium moisture content, a tendency also found for Gibbs free energy. 相似文献
150.
Schlomer Gabriel L.; Del Giudice Marco; Ellis Bruce J. 《Canadian Metallurgical Quarterly》2011,118(3):496
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