元学习算法选择机制及关联对性能的影响

提出一种元学习定义,从偏差/方差分解角度对元学习中学习算法的选取机制进行研究,得出了元级选用错误率低且偏差小的学习算法、基级学习算法按照错误率及方差从低到高排列的结论。鉴于标准数据集不能充分评估关联对元学习性能的影响,设计了一种模拟算法以产生模拟数据集。在UCI标准数据集和模拟数据集上的实验表明,同常用的多数投票等组合方法相比,基于算法选择机制的元学习表现出优良的性能,且分类器之间的负关联有助于性能的改进。     

The achievable region approach to the optimal control of stochastic systems

The achievable region approach seeks solutions to stochastic optimization problems by characterizing the space of all possible performances (the achievable region) of the system of interest and optimizing the overall system-wide performance objective over this space. This is radically different from conventional formulations based on dynamic programming. The approach is explained with reference to a simple two-class queueing system. Powerful new methodologies due to the authors and co-workers are deployed to analyse a general multi-class queuing system with parallel servers and then to develop an approach to optimal load distribution across a network of interconnected stations. Finally, the approach is used for the first time to analyse a class of intensity control problems.     

DVS系统硬实时周期任务动态调度算法

与实时任务的可调度分析不同,实时DVS调度在保证任务截止时间限制同时,还要关注任务执行的处理器功耗。功耗研究一段时间的累积效果,传统基于最坏执行时间的任务调度模型不能满足实时DVS调度需要。该文采用实际执行时间(AET)概率分布建立实时任务调度模型,利用随机分析的方法分析AET分布对实时DVS调度算法性能的影响,提出了基于平均执行时间的实时DVS动态调度算法。实验结果表明,该算法在任务具有不同AET分布情况下可保持稳定的功耗性能。     

The largest SNR distribution

The probability distribution of the maximum of normalized SNRs (signal-to-noise ratios) is studied for wireless systems with multiple branches. Explicit expressions and bounds are derived for the cumulative distribution function, probability density function, hazard rate function, moment generating function, nth moment, variance, skewness, kurtosis, mean deviation, Shannon entropy, order statistics and the asymptotic distribution of the extreme order statistics. Estimation procedures are derived by the methods of moments and maximum likelihood. An application is illustrated with respect to performance assessment of wireless systems.     

对采暖系统失水问题的探讨

从高校后勤采暖的实际状况出发,分析了采暖系统失水的主要原因和危害,提出了失水和节约用水的措施、途径,以求获得更佳的供暖效果。     

Multi-criteria decision support and evaluation of strategies for nuclear remediation management

Environmental emergency situations can differ in many ways, for instance according to their causes and the dimension of their impacts. Yet, they share the characteristic of sudden onset and the necessity for a coherent and effective emergency management. In this paper we consider decision support in the event of a nuclear or radiological accident in Europe. RODOS, an acronym for real-time on-line decision support system, is a decision support system designed to provide support from the early phases through to the medium and long-term phases. This work highlights the role of multi-criteria decision analysis (MCDA) within RODOS in ensuring the transparency of decision processes within emergency and remediation management. Special emphasis is placed on the evaluation of alternative remediation or countermeasure strategies using the multi-criteria decision support tool Web-HIPRE in scenario focused decision making workshops involving different stakeholder and expert groups. Decision support is enhanced by a module that generates natural language explanations to facilitate the understanding of the evaluation process, therefore contributing to the direct involvement of the decision makers, with the aim of increasing their confidence in the results of the analyses carried out, forming an audit trail for the decision making process and improving the acceptability of the system as a whole.     

论特别行政区制度的中国特色

特别行政区制度的宪制基础、政策基础和核心内容所体现的中国特色,说明特别行政区制度构成了有中国特色的单一制国家结构形式的重要组成部分,是中国特色政治文明的重大制度创新.     

'I'm Like a Tree a Million Miles from the Water's Edge': Social Care and Inclusion of Older People with Visual Impairment

The care and support of older people with visual impairmentis a neglected public-policy issue, despite the growing numbersaffected by sight loss in later life. A recently completed studyof four hundred people aged over fifty-five has gathered dataabout experiences of sight loss, coping strategies, supportneeds, home environments, social contacts and information needs.This paper reports on a prominent concern arising from research—theconnection between unmet social-care needs and social exclusion.Discussion focuses on identifying and assessing needs, majorproblems and priorities raised by interviewees, and serviceinitiatives that promote inclusive social care. Conclusionsare reached that social workers and other allied professionalscan best promote socially inclusive support through inter-agencyco-operation, and practical suggestions are presented as tothe possible shape and direction of collaborative work.     

我国现代大学制度创建的文化困境与路径依赖

现代大学制度创建与创新关乎大学共同体的发展,在大学制度创生中,会面临种种文化困境:对历史文化传统的继承和创新、人与制度的和谐与冲突、文化前提与制度环境的不同。而文化传统的不同,制度的差异,造成我们对大学制度的路径依赖。     

Nested or Networked? Future Directions for Ecological Systems Theory

Bronfenbrenner's ecological systems theory (EST) is among the most widely adopted theoretical frameworks for studying individuals in ecological contexts. In its traditional formulation, different levels of ecological systems are viewed as nested within one another. In this article, we use Simmel's notion of intersecting social circles and Bronfenbrenner's earlier writing on social networks to develop an alternative ‘networked’ model that instead views ecological systems as an overlapping arrangement of structures, each directly or indirectly connected to the others by the direct and indirect social interactions of their participants. We redefine each of the systems discussed by EST—micro, meso, exo, macro, and chrono—based on patterns of social interaction, and then illustrate how this alternative model might be applied in the classic context of the developing child. We conclude by discussing future directions for how the networked model of EST can be applied as a conceptual framework, arguing that this approach offers developmental researchers with a more precise and flexible way to think about ecological contexts. We also offer some initial suggestions for moving a networked EST model from theory to method.