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41.
集配货一体化VRP问题的具记忆功能的模拟退火算法研究   总被引:1,自引:0,他引:1  
针对集配货一体化车辆路径问题的特性,建立了考虑配送车辆出行固定成本、车辆出发满载系数等因素的更加符合实际的数学模型;并设计了一种带记忆功能的模拟退火算法求解模型,确保输出结果是每次寻优的最优解;最后通过算例计算,结果表明,算法求解更优,稳定性更好,计算效率也较高。  相似文献   
42.
文章基于主管教学的职能部门和有关院(系)单位之间的沟通协调、合作交流,特别是管理服务的实践经验,先从教学工作的背景分析入手,概括了教学秘书工作的核心内容,初步探索了现代高等学校教学秘书的工作范式。这对深化高校教育教学改革、提高秘书工作品质、提升教学服务及管理效率等具有一定的理论意义和现实意义。  相似文献   
43.
Within the United Kingdom there is growing awareness of the need to identify and support the small number of children who are living in families experiencing multiple problems. Research indicates that adverse experiences in childhood can result in poor outcomes in adulthood in terms of lack of employment, poorer physical and mental health and increases in social problems experienced. It is acknowledged that most of these children are known to child welfare professionals and that some are referred to social services, subsequently entering the child protection system. This paper reports research conducted with 28 experienced child welfare professionals. It explores their views about families known to the child protection system with long‐term and complex needs in relation to the characteristics of children and their families; the process of intervention with families; and the effects of organisational arrangements on practice. The research indicates that these families are characterised by the range and depth of the problems experienced by the adults, such as domestic violence, mental health difficulties and substance misuse problems, and the need for professionals to have good inter‐personal skills and access to specialist therapeutic services if families are to be supported to address their problems. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
44.
This article poses a challenge to the orthodox binary, conceptualization of work–life balance only made possible by relying on the widespread ‘clock time’ worldview, which understands employment practices in terms of the basic time = money equation. In particular, it is the balance metaphor which relies on a quantification of both work and life in order to make sense and can therefore be seen to be based on an understanding of time as a measurable and value‐able unit. This article seeks to begin the exercise of examining the concept of work–life balance through a broader concept of the temporal dimension than simply limited quantitative notions. Two temporal themes are reported from a study which identified employees who had customized their working pattern to suit the various and multi‐dimensional facets of their lifestyles and thereby successfully improved their work–life balance. Participants in this study demonstrated that an improved work–life balance is more about a mind‐set that refuses to be dominated by a work temporality and is determined to create ‘me time’ rather than e.g. simply choosing a four day week or a part‐time job. It is argued that the notion of work–life balance is more usefully conceptualized within a broader notion of ‘livingscapes’ which contain both elements of work and life and that as researchers, our challenge must be to reflect the complexity of this weave within our analyses of individuals’ work–life balance.  相似文献   
45.
在形状记忆合金的相变过程中,如果温度升至TS后停止升温,并降温至马氏体相变结束温度Mf以下,则在下一次完全相变循环中出现动力学停顿,而这一动力学停止温度点与上次的停止温度密切相关,这一现象被称为温度记忆效应。该文通过示差扫描量热法对TiNi和TiNiCu合金薄膜进行一次或连续几次不完全相变,系统地研究了温度记忆效应。结果表明,不仅温度记忆效应是形状记忆合金固有现象,而且温度记忆效应与马氏体变体间的弹性能及母相和马氏体相之间的共格应变密切相关。  相似文献   
46.
以艾宾浩斯的遗忘曲线为基本框架,通过拼图性学习和常规性学习两种不同学习生字方法的实验比较,对儿童识字的一般性规律进行研究。得到结论:拼图性识字在记忆的保持上优于常规性识字;拼图性识字在学习有笔画难度的字上优于常规性识字;拼图性识字同样符合艾宾浩斯的遗忘曲线规律。拼图性识字教学符合儿童以动作思维为主的认识特点,符合儿童心理的年龄特征,能提高对字形记忆的效果,让儿童可以有效、有趣、自主进行早期识字学习。  相似文献   
47.
为探究小功率车载逆变器的散热性能,利用CFD软件对车载逆变器建立有限元三维模型,用笛卡尔网格划分系统对重点部位进行网格加密处理,通过在不同工况下的数值仿真计算,得出逆变器整体及各个元器件的发热情况。在数值仿真结果的基础上,设计相关实验,在不同环境温度的工作条件下,对车载逆变器中各个元器件的工作温度进行实验测试。测试表明各个元器件在不同环境温度、外部负载的工况下,工作温度都控制在100 ℃左右,分析实验值与模拟值的误差,其最大误差在3.4%以内。数值仿真计算结果有较高的精确度。  相似文献   
48.
为了研究不同工作条件下R22替代工质在空气源热泵热水器中所展现的不同系统性能,课题组利用单级压缩制热循环系统对其替代工质做了理论分析,经计算得出R134a和R407C的性能较为优异,但是考虑到2者具有较高的全球变暖潜能值,并不适合作为长期使用的工质,而R32与其他制冷剂相比,除却排气温度稍高的问题以外,其综合性能最佳。随着市场上有效降低压缩机排气温度的技术逐渐成熟,在空气源热泵热水器中,R32作为R22的替代制冷剂将具有很好的应用前景。  相似文献   
49.
Has the image of Che Guevara lost its power to evoke radical politics in the face of pervasive commodification? The commercialization of this 1960s political icon has called into question the power of the market to shape collective memories. Meanwhile, antisystemic movements of the left continue to erect his image at protest events. In light of this contest over how Che Guevara is remembered, we investigate, using data from a survey of Spanish citizens, who is most likely to recall him. We find qualified support for the theory of generational imprinting—Che is more often recalled by those generations who saw him rise to prominence during their formative years, although prominent as a collective symbol rather than as a living person. Our results also corroborate the claim that historical figures or events are more salient for, and therefore more likely to be remembered by, some subgenerational units than others. Thus, although the younger generations are in general more likely than their elders to recall Che, he is most frequently remembered by the highly educated leftists who espouse postmaterialist and posttraditionalist values and identify more with their local regions than with the nation of Spain. These patterns suggest that, in contrast to the dire predictions of mass culture theorists, the memory of Che Guevara has become increasingly tied to markers of social, ethnic‐regional, and political identity.  相似文献   
50.
The contributions that adult men and women make to households in terms of paid and unpaid work have undergone substantial change, particularly in respect of women's responsibility for income generation, and have been seen as part of the processes of individualization. Recent contributions to the literature have suggested that children are now acquiring independence earlier as part of those same processes. The paper uses qualitative methods to explore the way in which parents in two-parent families, where both are employed, perceive the risks attached to children's exercise of greater independence, how they seek to ‘manage’ those risks and how far the perceptions of parents accord with those of children. We find parents’ perceptions of risk to be strong, but to have little to do with working patterns. In addition, they are often at odds with the actual behaviour of the child. Risks are managed by negotiation, in which children played an active part. We are also able to make some preliminary comments on the difficulties of interpreting scale measures in relation to interview evidence.  相似文献   
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