气压传动与控制在电子专用设备上的应用

气压传动与控制已成为电子专用设备研制过程中一项不可缺少的内容 ,必须进行合理的气动系统设计及其控制 ,选择相应的气动元件以满足设备的功能要求。概述了气压传动与控制在电子专用设备上的应用。     

Saccadic velocity and activation: development of a diagnostic tool for assessing energy regulation

The hypothesis was tested that peak velocity of saccadic eye movements in visual motor tasks varies with variables related to energy regulation. The hypothesis is based on the cognitive-energetical performance model of Sanders. An experimental paradigm was developed in which saccadic peak velocity of task-relevant eye movements is measured while a choice reaction task is carried out. Confounding factors of saccadic amplitude and movement direction were controlled. The task was designed in such a way that in each trial subjects performed a target saccade towards an imperative stimulus and a return saccade after the manual response back to the centre of the screen. For both types of saccades the experimental variables were foreperiod duration (short versus long), knowledge of results (with versus without), postsaccadic demand (low versus high) and time on task (five 30-min intervals). In two experiments, there are main and interaction effects of the task variables on peak saccadic velocity. Return saccades are slower than target saccades, but not in the case of high postsaccadic demand. Knowledge of results increases peak saccadic velocity, but more so for return than for target saccades. Time on task leads to a decrease in peak saccadic velocity, which is much stronger for return than for target saccades; furthermore this effect is more pronounced after short than after long foreperiods. Peak saccadic velocity is changed within seconds. The results support the hypothesis. Peak saccadic velocity of task related eye movements reflects energy regulation during task performance. The paradigm will be developed as a diagnostic tool in workload measurement.     

人工神经网络专家系统在门窗选型中的应用

本文提出了一个将神经网络专家系统的设计思想引入门窗选型过程的应用模型,从而提高了门窗选型的合理性,也充分发挥了神经网络及专家系统的各自优点。文中主要介绍了基于神经网络专家系统的门窗选型模型的结构和推导过程,此模型在实际应用中确实取得了令人满意的效果。     

轨迹与选择:从政治民主到行政民主

政治民主给人民管理国家的可能性与现实性存在很大距离。必须同时实行行政民主,让公民渗透到行政权力行使的始终,才能保证行政权力始终行驶在民意的轨道上。制度选择与价值回归是行政民主的重要内容。各国公共行政都进行了适应性变革。     

高维数据空间金字塔技术研究

被视为破解“维度灾”的金字塔技术是有效的高维空间数据索引方法之一,它是基于一种依赖数据维度的非平均分割策略,先对d维数据按维度进行空间分割成具有公共顶点的2d个金字塔,然后提供d维数据点到1维金字塔值的一一映射,通过一种有序的一维索引结构建立有效的索引。文章结合高维数据空间索引的建立,提出金字塔技术所依赖的维度的选维策略和域外插入处理所需的适应性处理方法,实际效果较好。     

以太网交换机的选择

本文对以太网交换机的分类和性能参数进行了讨论，在此基础上给出了选择交换机的基本原则和主要依据。     

Speed choice by drivers: The issue of driving too slowly

Quite correctly, the majority of road safety speeding initiatives focus on drivers travelling at excessive speeds. This study, however, focused on the potential problem of driving too slowly. Six thousand, four hundred and eighty vehicles from around the Perth metropolitan area in Western Australia had their speeds recorded; observations were also made of these vehicles to identify characteristics of the driver and vehicle. In addition, a community survey with 240 members of the public was conducted to examine their attitudes towards slow drivers. As expected, results showed that older drivers drove more slowly than the other age brackets, women drove more slowly than men, and that heavily laden vehicles drove more slowly than other types of vehicles. Additionally, the slowest days were weekdays and the quickest were Saturdays. Community attitudes, generally mirrored the observational findings, and indicated that the public believed that slow driving was sometimes a safety problem causing some accidents. These data are discussed, and some possible countermeasures are briefly introduced to address the problem.     

Food4Me study: Validity and reliability of Food Choice Questionnaire in 9 European countries

This analysis has been conducted to explore the validity and reliability of the Food Choice Questionnaire (FCQ) across 9 European countries. Variation in the factor structure and the perceived importance of food choice motives have been compared cross-nationally. Volunteers (N = 9381) were recruited from an existing panel of a social research agency to take part in the Food4Me survey in Germany, Greece, Ireland, Poland, Portugal, Spain, the Netherlands, the UK and Norway. The survey was administered on-line. Configural, metric and scalar invariance fell within acceptable limits and were consistent across the 9 countries. All reliability parameters were above acceptable levels. Factor analysis confirmed that all items loaded onto the same 9 factors established by Steptoe and Pollard (1995). There was highly significant agreement in the relative importance of food choice factors between countries. Price was ranked as most important food choice factor in five countries (Spain, Greece, Ireland, Portugal and the Netherlands), sensory appeal was ranked first for three countries (Norway, Germany and the UK) while natural content was ranked as the most important factor in Poland. Familiarity and ethical concern were consistently ranked as least important in all countries. These data suggest that the FCQ is a suitable tool for exploring food choice motives across different European populations. Differences in relative importance of factors within countries may need to be taken into account in dietary health intervention and food product development.     

An efficient methodology for assessing attention to and effect of nutrition information displayed front-of-pack

A methodology for assessing attention to and effect of nutrition information displayed front-of-pack is presented. The methodology is based on an integration of the visual search paradigm, the choice paradigm and eye-tracking measures, and moves beyond reliance on self-report measures for attention and choice. Rather the following measures are obtained: (1) respondents’ eye-movements, in terms of dwell time, fixation duration, number of fixations, and saccade size; (2) response times indicating the speed with which choice decisions are made; and (3) consumers’ actual choices from an assortment. The efficiency and sensitivity of the methodology is illustrated in a small scale empirical application. Overall, the methodology seems to be a promising tool for answering puzzling questions in consumer attention and decision making with straightforward potential extensions to enlarge its scope.     

A CONTINGENCY APPROACH TO CHOICE

The moment of choice, when a decision option is identified as being preferred, is a key stage in a decision-making process. Some explicit or implicit mechanism, be it optimising, satisficing or a combination of the two, is required to make a choice. Dependable decision-making requires an appropriate choice mechanism, but the process and criteria by which a choice mechanism is selected are seldom addressed. A contingency approach to choice is proposed in which a choice mechanism is selected according to the characteristics of the information available and the meta-level constraints and objectives of the decision-maker. Information used in the choice is characterised according to the extent and type of uncertainty. The importance in effective decision-making of meta-level requirements, for example for inclusive and transparent mechanisms, is discussed. Normative and fuzzy choice mechanisms are cast within a generic framework of choice mechanisms. A new theory of choice based on interval probabilities is introduced for use in some situations where existing theories of choice are inappropriate.