ATLAS: Accelerated torus-like angular source for fusion neutronics applications

There is increasing demand for fast and accurate neutronics analysis to be conducted on specific ITER components. The ATLAS (accelerated torus-like angular source) algorithm has been developed to accelerate such neutronics calculations by approximating the 3-D plasma volume source as a surface source at the first-wall region of interest. The ATLAS routine rapidly calculates the angular distribution of the unscattered neutron flux at the chosen first wall location, on a discrete angular grid, and writes a surface source for both MCNP and Attila. This discretised source can then be used to accurately reproduce the full 3-D toroidal volume source in angle and energy, and to quickly simulate the irradiation of individual components or regions in the ITER model. While designed for ITER, the method is general in implementation and can be applied to any tokamak.     

Effect of dextrans of differing molecular weights on the rheology of wheat flour doughs and the quality characteristics of pan and arabic breads

Dextrans (α-1-6-D-glucans) with weight-average molecular weights (Mw) ranging from 10 to 500 kDa were used at a rate of 20 g kg^?1 (flour basis) in order to modify doughs made from flour of the Australian hard-grained wheat cultivars Banks, Sunco and Hartog. Doughs containing dextran fractions with Mw below 100 kDa showed significant (P ± 0.01) reductions in Farinograph maximal consistency and significant increases in Farinograph development time. Additions of dextrans also resulted in significant increases in maximal resistance and significant reductions in extensibility when doughs were subjected to Extensograph testing. After addition of dextran fractions with Mw of 100 kDa or less, there were significant reductions in loaf volumes in pan bread of the cultivar Hartog manufactured by a rapid dough system and in pan bread of the cultivars Banks and Hartog made by a fermented dough system. Arabic bread supplemented with dextrans had poorer internal and keeping qualities, and reduced bread surface area, leading to significantly decreased quality scores. These observations are discussed in relation to possible interactions between neutral polysaccharides and other flour components.     

Report of the Policy and Planning Board: 1958.

The Policy and Planning Board provides this report to the members of the American Psychological Association (APA) on its activities in 1957. The board met twice, in Chicago: November 8, 1957 and April 2-3, 1958. This year the board put aside any major questions about the organization of the APA--a matter that has occupied much of our time in the past two years. The board turned its attention, rather, to the kind of a role the APA ought to play in the public and professional life of our time. In addition, we acted on a number of limited issues which are summarized in this report. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

全世界的设计都是相通的 2008年Andrew martin室内设计大奖

2008年10月29日,由缤纷杂志与ANDREW MARTIN联合主办的2008 ANDREW MARTIN国际室内设计年奖获奖作品全国巡回展.在北京博洛尼家居体验馆拉开帷幕。并于10月31日在杭州.11月21日在上海、11月25日在深圳、11月26日在广州盛大开展。     

Modelling sweetness and texture perception in model emulsion systems

Model emulsion samples, prepared subject to a d-optimal response surface design, were used to investigate the effect of rapeseed oil, sugar and hydroxypropyl methyl cellulose thickener (HPMC) on perceived sweetness, textural attributes (thickness, stickiness, mouth-coating, dispersing), instrumental measures of apparent viscosity 50 s⁻¹ and Kokini oral shear stress. An increase in oil, sugar and HPMC resulted in an increase in perceived thickness, stickiness and mouth-coating, and a decrease in dispersion; sweetness was enhanced by the addition of both sugar and oil but suppressed by the addition of HPMC. Viscosity and Kokini oral shear stress were well correlated with oral thickness (r ² > 0.9). Validated multiple linear regression models highlighted several 2-factor interactions between ingredients. Model statistics indicated that the variation in data was well explained; the models were predictive and could be used to navigate the design space. Samples predicted to be iso-thick and iso-sweet could not be discriminated (P > 0.10) in a 3-alternative forced choice (3-AFC) test using 35 panellists.     

Feasibility study and tool design of using shape memory alloy as tool-structural elements for forming-error compensation in microforming

Taking advantage of the special properties of shape memory alloys (SMA), a concept of error compensation for microforming with the use of SMA as an actuating/enhancing element was proposed. Simplified analysis of tool structures, FE simulation of forming processes, and experimental tests on the tubular cylinders with SMA enhancement wires showed that the pressures created due to the geometric change of the SMA under the temperature above its transformation value could generate sufficient contraction of the cylinders, compared to the forming-error values predicted for microforming, and hence, they are potentially feasible for the applications to error-compensation in microforming. Based on these results, a detailed microforming-tool design with an SMA-enhanced ring structure has been produced.     

In situ measurements of water transfer due to different mechanisms in a proton exchange membrane fuel cell

Water management is of critical importance in a proton exchange membrane (PEM) fuel cell, in particular, those based on a sulfonic acid polymer, which requires water to conduct protons. Yet there are limited in situ studies of water transfer through the membrane and no data are available for water transfer due to individual mechanisms through the membrane in an operational fuel cell. Thus it is the objective of this study to measure water transfer through the membrane due to each individual mechanism in an operational PEM fuel cell. The three different mechanisms of water transfer, i.e., electro-osmotic drag, diffusion and hydraulic permeation are isolated by specially imposed boundary conditions. Therefore water transfer through the membrane due to each mechanism is measured separately. In this study, all the data is collected in an actual assembled operational fuel cell. The experimental results show that water transfer due to hydraulic permeation, i.e. the pressure difference between the anode and cathode is at least an order of magnitude lower than those due to the other two mechanisms. The data for water transfer due to diffusion through the membrane are in good agreement with some of the ex situ data in the literature. The data for electro-osmosis show that the number of water molecules dragged per proton increases not only with temperature but also with current density, which is different from existing data in the literature. The methodology used in this study is simple and can be easily adopted for in situ water transfer measurement due to different mechanisms in other PEM fuel cells without any cell modifications.     

Measures of larval lake whitefish length and abundance as early predictors of year-class strength in Lake Michigan

Many lake whitefish stocks in Lake Michigan have experienced substantial declines in growth and condition since the 1990s. Reduced growth and condition could result in reduced quality or quantity of eggs produced by spawning females, which in turn could negatively impact recruitment. We evaluated the potential for reduced recruitment by measuring early life stage density and length, and we discuss the utility of these measures as early indicators of lake whitefish year-class strength. Overall, mean larval density (number per 1000 m³ ± SE) in Lake Michigan was greater in 2006 (373.7 ± 28.3) than in 2005 (16.6 ± 24.8); whereas, mean length (mm ± SE) of larval lake whitefish was smaller in 2006 (12.87 ± 0.07) than in 2005 (14.38 ± 0.13). The ratio of zooplankton to fish density did not show an expected relationship with larval fish density or length. Rather, variation in larval density was best explained by a multiple-regression model that included larval length, spring wind intensity, and adult stock density as predictor variables. Our results suggest that the density of larval lake whitefish is not directly regulated by temperature or zooplankton density at the time of emergence, but that a potential for density-dependent regulation exists when larval emergence rates are high. We conclude that the observed declines in growth and condition of adult lake whitefish are not resulting in substantial reductions in recruitment.     

Water Resources Management and Integrated Water Resources Management (IWRM) in Cameroon

Cameroon is blessed with abundant water resources. Rapid population increase, unplanned urbanisation, intensive industrial and socio-economic development have led to poor and unsustainable management of these resources. Integrated Water Resources Management (IWRM) is a promising approach in ensuring sustainable management of Cameroon’s water resources. It entails management of water for various purposes and not for a single purpose which therefore involves different stake holders aiming at achieving sustainable water resources management. This paper seeks to evaluate recent efforts to implement in IWRM in Cameroon by examining the institutional framework for IWRM in Cameroon, conditions for the implementation of IWRM and proposes reforms for improving IWRM in Cameroon. The paper concludes that reforms such as public participation at local council levels, recognition of water as both an economic and a social good, putting IWRM within the larger context of Integrated Natural Resource Management (INRM) and the exploitation of mathematical models within hydrological basins will improve IWRM in Cameroon.