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101.
《International journal of human-computer studies》2014,72(2):207-223
Unhealthy eating behavior is a major contributing factor to the onset of several diseases and health conditions (e.g., obesity, type 2 diabetes). It is therefore not surprising that health interventions aimed at modifying dietary behavior have been identified as the cornerstone treatment for many health conditions. Interventions that use persuasive technology can be effective for motivating healthy eating behavior, and recent years have witnessed an increasing number of persuasive technologies with the purpose of promoting healthy eating behavior or attitude by manipulating various determinants of healthy behavior. However, these applications generally take a one-size-fits-all approach that is biased toward individualistic cultures. To resolve this problem, we propose culturally relevant design approaches for tailoring persuasive technology interventions to collectivists and individualistic cultures. Our guidelines are based on a large-scale survey of 554 participants' (collectivist=306 and individualist=247) eating behavior and associated determinants – identified by Health Belief Model – to understand how healthy eating behavior relates to various cultural groups and sub-groups. We developed two models of healthy eating behavior for the collectivist and individualistic cultural groups identified by Hofstede, and an additional eight models to investigate the moderating effect of gender and age on healthy eating behavior. We then explored the similarities and differences between the models and developed persuasive profiles of motivators of healthy eating behavior for each group. Additionally, we proposed two approaches for designing culturally relevant persuasive applications based on our results. The first is a one-size-fits-all approach that will motivate the majority of the population, while not demotivating any user. The second is a personalized approach that will best motivate a particular cultural group. Finally, to make our approaches actionable in persuasive intervention design, we map the theoretical determinants of healthy eating behavior as identified by Health Belief Model to common persuasive system design strategies. 相似文献
102.
现有的频谱感知算法主要在时间、频率以及地理空间维度进行检测,对角度维的利用尚不成熟。将多天线技术中的到达角（AOA, angle of arrival）估计算法应用到频谱感知领域,提出了2种基于空间谱的盲频谱感知算法,分别为最大—最小延迟相加谱值比检测和平均—最小延迟相加谱值比检测。利用空域匹配滤波的优势,新算法在低信噪比下得到了较高的检测概率,同时为角度维的频谱接入提供了AOA信息,从而提高了频谱利用率。此外,运用随机矩阵理论,推导了检测阈值和检测概率的理论值。仿真结果表明,在Nakagami-m信道下,提出的算法具有比现有盲感知算法更优的检测性能。 相似文献
103.
Dines Bjorner 《International Journal of Software and Informatics》2011,5(3):509-523
Boehm[13,37] is credited to have formulated the \"Two Rights\" of software: the problem of getting the right software and the problem of getting the software right. The development processes needed to achieve software that is right, to us, requires that a proper study of the application domain be done before a serious requirements study is attempted;and to achieve the right software, that is, software that is correct, to us, requires that a proper engineering degree of formalism be applied to the entire development process; that is, that we re-interpret classical development processes[14]. We shall in this paper focus only on the issue of obtaining the right software. In this paper talk we shall outline what we mean by a proper study of the application domain and how it influences the requirementsdevelopment. 相似文献
104.
Margus Veanes Nikolaj Bjφrner Yuri Gurevich Wolfram Schulte 《International Journal of Software and Informatics》2009,3(2):149-170
Abstract State Machines (ASMs) allow modeling system behaviors at any desired level of abstraction, including a level with rich data types, such as sets, sequences, maps, and user-de.ned data types. The availability of high-level data types allow state elements to be represented both abstractly and faithfully at the same time. In this paper we look at symbolic analysis of ASMs. We consider ASMs over a .xed state background T that includes linear arithmetic, sets, tuples, and maps. For symbolic analysis, ASMs are translated into guarded update systems called model programs. We formulate the problem of bounded path exploration of model programs, or the problem of Bounded Model Program Checking (BMPC) as a satis.ability problem modulo T . Then we investigate the boundaries of decidable and undecidable cases for BMPC. In a general setting, BMPC is shown to be highly undecidable (Σ11-complete); and even when restricting to .nite sets the problem remains re-hard (Σ01-hard). On the other hand, BMPC is shown to be decidable for a class of basic model programs that are common in practice. We use Satis.ability Modulo Theories (SMT) for solving BMPC; an instance of the BMPC problem is mapped to a formula, the formula is satis.able modulo T if and only if the corresponding BMPC problem instance has a solution. The recent SMT advances allow us to directly analyze speci.cations using sets and maps with specialized decision procedures for expressive fragments of these theories. Our approach is extensible; background theories need in fact only be partially solved by the SMT solver; we use simulation of ASMs to support additional theories that are beyond the scope of available decision procedures. 相似文献
105.
交通荷载下层状道路系统动应力特征分析 总被引：2，自引：1，他引：1
通过原位监测试验的相关数据,总结出层状道路系统在交通荷载下的动应力时空分布规律。在现有弹性层状体系理论基础上,采用传递矩阵方法,结合黏弹性运动方程,推导交通荷载下三维黏弹性层状道路系统的动力响应解答,采用Matlab矩阵分析软件进行数值计算,和原位监测试验的结果进行对比分析。在上述分析的基础上采用快速拉格朗日有限差分程序FLAC3D编制交通荷载下层状道路系统动力响应分析程序,对层状道路系统进行三维数值模拟计算,分析层状道路系统内部动应力和动位移时空分布规律,并将计算结果与现场原位监测试验进行对比分析,证明计算程序的有效性。研究结果表明：(1) 浅层动附加应力随深度增加加速衰减,而深层动附加应力的衰减率不大;(2) 路面结构能有效扩散动应力;(3) 车辆自身振动将使动应力明显增大;(4) 动附加应力具有累积效应。 相似文献
106.
增量式设计方法是软件开发中常用的一种设计方法,但是对其进行形式化研究的并不多。论文研究用多项式动态系统方法开发软件时是否可以用增量式设计方法。首先通过一个反例说明并不是在任何情况下都可以用增量式设计方法,然后通过定义软件需求的继承性,得到增量式软件设计的一个充分条件：当已经设计的软件需求具有继承性时,可以对新的软件需求采用增量式设计。 相似文献
107.
陈剑 《岩石力学与工程学报》2005,24(1):154-159
在工程地质学和岩体力学的基础上发展形成了一门新的学科——地质工程学。从工程地质发展到地质工程,是从认识世界走向改造世界,是一个质的飞跃。地质工程学的产生反过来将大大推进地质学和岩石力学等学科的发展。论述了地质工程学的产生、理论与技术、最新进展以及目前存在的问题,并对其今后的发展趋势进行了展望。 相似文献
108.
109.
本文概述了教育技术的新形势 ,提出了在新形势下电化教育的六项基本建设 :建设现代化的教育技术环境 ;建设新型的现代化教材体系 ;建设和探索新型的教学模式 ;建立现代化教学理论体系 ;建设新型的现代化教师队伍 ;建立现代化教育网络系统 相似文献
110.
首次在命题逻辑系统中引入理论的真度概念,使得真度的概念由公式的真度推广为公式集的真度,从而简化了发散度的概念;在逻辑系统Gn中讨论了理论Γ1、Γ2和Γ1∪Γ2的真度、相容度和发散度之间的关系。 相似文献