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81.
Overweight and obesity are global public-health problems and unhealthy restaurant meals have been identified as one contributing factor. Given the increase in restaurant meals and the number of chefs and restaurants throughout the world, small changes in restaurant meals can have a large public health impact. However, to ensure that chefs and operators are able to provide changes that diners will accept and find appealing, an understanding of diners’ desire for healthier menus items and the barriers faced in choosing healthier meals is required. As such we conducted an international consumer study to identify these barriers and needs. A cohort of restaurant diners was recruited from ten countries: United Kingdom, United States of America, Germany, Poland, Turkey, Russia, Brazil, South Africa, Indonesia and China (n = 5000, aged 18–65 years, 50% females). Participants completed a comprehensive web-based questionnaire on aspects related to healthy eating at restaurants. Globally only 18% of the sampled diners were strongly satisfied with current healthy options on restaurant menus. Among the diners there was a preference to have “slightly healthier” options. The top 3 small changes that these diners wanted to see included on restaurant menus to make them healthier included: steamed, baked or grilled instead of fried, fresh ingredients used, and served with plenty of vegetables. Taste, price and satiation were seen as key barriers to current healthy options. Diners had clear preferences for when they wanted to see healthy items on the menu in terms of time of day, time of the week and occasions. Country, age and gender had a large influence on preferences, while personal factors such as diet type, family status and food reactions had minimal influence. In the current study, diners were largely unsatisfied with current healthy options and clear barriers and triggers for healthier meals were identified. Nutritionists, dietitian, chefs and managers working for restaurants and other out of home food services can leverage these insights to provide healthier and appealing meals. 相似文献
82.
In Part I of the paper ((1999), Trib. Trans., 42, pp. 851–859) we investigated the effect of the polyethylene concentration on the film forming properties in a rolling bearing. This second part presents the influence of the polymer additive concentration on the traction behavior experienced using a two-disk machine at different temperatures and contact pressures. By using the traction data, a semi-empirical approach for determining the effective lubricant theological parameters in EHL contacts was performed. Using this approach, the effect of polymer concentration upon rheological parameters that appear in the Johnson and Tevaarwerk model with Eyring stress was quantified. 相似文献
83.
邵蓉 《石油化工高等学校学报》2005,18(2):76-79
基于集成电路进行数字系统设计时,依据电路性能指标的描述,首先构造输入输出关系的真值表,建立算法模型,直接依据行为描述的真值表而设计的电路结构不明确,不利于逻辑综合;在行为域分析基础上优化设计,可得数据流描述模型,使VHDL描述模型简化,但其描述对所设计电路结构不明确,VHDL描述过程中要考虑一系列不适用于逻辑综合的约束条件的限制;门级结构域层次化优化描述模型给出明确的设计电路结构,通过描述模型对逻辑门级仿真可得到精确的电路的时序信息。 相似文献
84.
网络发展对大学生行为及道德的影响 总被引:1,自引:0,他引:1
本文从大学生效率观念、平权意识、社会交往、学习行为等四个方面,展开论述了网络发展对大学生的行为及道德的影响,并着重从正面影响和反面影响相对比进行论述,最后提出了应对策略. 相似文献
85.
Isaac Rudomín Erik Milln Benjamín Hernndez 《Simulation Modelling Practice and Theory》2005,13(8):741-751
In a previous paper we generated animated agents and their behavior using a combination of XML and images. The behavior of agents was specified as a finite state machine (FSM) in XML. We used images to determine properties of the world that agents react to. While this approach is very flexible, it can be made much faster by using the power available in modern GPUs. In this paper we implement FSMs as fragment shaders using three kinds of images: world space images, agent space images and FSM table images. We show a simple example and compare performance of CPU and GPU implementations. Then we examine a more complex example involving more maps and two types of agents (predator–prey). Furthermore we explore how to render agents in 3D more efficiently by using a variation on pseudoinstancing. 相似文献
86.
Duetotheirhighstrength,modulusandfracture toughnessaswellasgoodadhesionandthermalre sistance[1],epoxyresinsasmatricesarewidelyused inaeronautics,astronautics,transportation,sports andotherindustry.Standardepoxyresinsareusually basedonDGEBA(diglycidyletherofbisphenolA),whichneedsactivehydrogenorotheractivegroupsto opentwoepoxyrings.Four functionalepoxylike TGMDA(tetraglycidylmethylenedianiline)isoften usedforhigh performanceepoxymatrixcomposites becauseofitsrelativelyhighercross linkingdens… 相似文献
87.
A. Pretschner O. Slotosch E. Aiglstorfer S. Kriebel 《International Journal on Software Tools for Technology Transfer (STTT)》2004,5(2-3):140-157
Model-based testing relies on abstract behavior models for test case generation. These models are abstractions, i.e., simplifications. For deterministic reactive systems, test cases are sequences of input and expected output. To bridge the different levels of abstraction, input must be concretized before being applied to the system under test. The systems output must then be abstracted before being compared to the output of the model.The concepts are discussed along the lines of a feasibility study, an inhouse smart card case study. We describe the modeling concepts of the CASE tool AutoFocus and an approach to model-based test case generation that is based on symbolic execution with Constraint Logic Programming.Different search strategies and algorithms for test case generation are discussed. Besides validating the model itself, generated test cases were used to verify the actual hardware with respect to these traces. 相似文献
88.
This work presents a new methodology of approximation of functions. The identification is done graphically, stage-by-stage, taking into account the form of the generating functions. The above method is developed in this article within the scope of an efficient tool for modeling physical systems and as a reliable curve-fitting method that can use any basic function. Thus, it represents a non-linear identification procedure. On the one hand, simulated cases that do not represent any physical model are studied, and on the other hand, real cases that model physical systems as rubber behavior law are illustrated. The Ogden hyperelastic and the extended Gent–Thomas models for rubber materials are shown to give an accurate prediction of Treloars classical data with the help of mechanical parameters evaluated by the stage approach. Critical and comparative analyses of the stage approach are presented with the usual non-linear iterative procedures such as the non-linear least squares. 相似文献
89.
The service oriented architecture of grid computing has been thoughtfully engineered to achieve a service level virtualization: not only should a grid be a virtual machine (also known as a virtual organization, VO) of unbounded computational power and storage capacity, but also should the virtual machine be serviceable in all circumstances independent from serviceability of any of its component. At present, a grid VO as a result of service level virtualization only is more or less confined to participants from scientific computing communities, i.e., can have a limited scale. It is widely agreed that for a grid to pool resources of truly unbounded scale, commercial enterprises and in particular server-abundant financial institutions, should also “go for the grid,” i.e., open up their servers for being used by grid VO constructions. We believed that it is today's inadequate strength of the grid security practice that is the major hurdle to prevent commercial organizations from serving and participating the grid.This article presents the work of Daonity which is our attempt to strengthening grid security. We identify that a security service which we name behavior conformity be desirable for grid computing. Behavior conformity for grid computing is an assurance that ad hoc related principals (users, platforms or instruments) forming a grid VO must each act in conformity with the rules for the VO constitution. We apply trusted computing technologies to achieve two levels of virtualization: resource virtualization and platform virtualization. The former is about behavior conformity in a grid VO and the latter, that in an operating system. With these two levels of virtualization working together it is possible to build a grid of truly unbounded scale by VO including servers from commercial organizations. 相似文献
90.