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Collaborative research, defined as research involving actors participating in the problem situation under study, has an important role in operational research, strategic management and systems thinking. In a recent study, we found that a strong organizational focus incorporated into many soft operational research (OR) approaches is inadequate for studying societal problem situations, which are fragmented and have no clear boundary. Specifically, we failed to find a process of identifying individuals that is capable of representing the perspectives of actors and sufficient for research into societal problem situations. We found no clear terminology accounting for ontological differences between actors, individuals representing them and conceptual representations of acting entities. In response to this gap in the literature, we propose terminology that differentiates among actors (individuals or collective entities in the real world), experts (individuals capable of representing the perspective of an actor) and agents (ideal-typical representations of actors). Based on this terminology, we propose an iterative method to guide the assembly of an expert group to undertake collaborative research into societal problem situations. To demonstrate the application of our method, we present selected insights from our study in an electronic supplement.  相似文献   
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首先对Web Services的安全技术和访问控制的研究情况进行简单回顾,介绍XACML(eXtensibleAcces s Control Markup language)中的常用术语,然后介绍了一个Web Services的面向服务的基于角色的访问控制系统和安全结构模型,从服务方面和属性方面加强对服务的访问控制.在该体系结构模型中,使用SOAPProxy加强对Web Services的访问控制.通过设计安全cookies和安全SOAP消息,在Web Services上实现基于角色的访问控制.最后给出此系统有待解决的问题.  相似文献   
3.
This study was to evaluate acoustic changes in student actors' voices after 12 months of actor training. The design used was a longitudinal study. Eighteen students enrolled in an Australian tertiary 3-year acting program (nine male and nine female) were assessed at the beginning of their acting course and again 12 months later using a questionnaire, interview, maximum phonation time (MPT), reading, spontaneous speaking, sustained phonation tasks, and a pitch range task. Samples were analyzed for MPT, fundamental frequency across tasks, pitch range for speaking and reading, singing pitch range, noise-to-harmonic ratio, shimmer, and jitter. After training, measures of shimmer significantly increased for both male and female participants. Female participants' pitch range significantly increased after training, with a significantly lower mean frequency for their lowest pitch. The finding of limited or negative changes for some measures indicate that further investigation is required into the long-term effects of actor voice training and which parameters of voicing are most targeted and valued in training. Particular investigation into the relationship between training targets and outcomes could more reliably inform acting programs about changes in teaching methodologies. Further research into the relationship between specific training techniques, physiological changes, and vocal changes may also provide information on implementing more evidence-based training methods.  相似文献   
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The recent development of cloud computing is touted to offer promising opportunities for service delivery to organizations and communities by sharing computing power, storage and network infrastructure in a more effective and efficient manner. Cloud computing also bears many other issues, particularly in the context of non-democratic countries. These issues may include security concerns associated with the use of shared resources, embedded control and monitoring systems, physical storage locations and their management as well as the tools and services that otherwise may give oppressive regimes the ability to impose yet more restrictive Internet access on their citizens.  相似文献   
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This paper demonstrates that it is possible to produce automatic, reconfigurable, and portable implementations of multimedia decoders onto platforms with the help of the MPEG Reconfigurable Video Coding (RVC) standard. MPEG RVC is a new formalism standardized by the MPEG consortium used to specify multimedia decoders. It produces visual representations of decoder reference software, with the help of graphs that connect several coding tools from MPEG standards. The approach developed in this paper draws on Dataflow Process Networks to produce a Minimal and Canonical Representation (MCR) of MPEG RVC specifications. The MCR makes it possible to form automatic and reconfigurable implementations of decoders which can match any actual platforms. The contribution is demonstrated on one case study where a generic decoder needs to process a multimedia content with the help of the RVC specification of the decoder required to process it. The overall approach is tested on two decoders from MPEG, namely MPEG-4 part 2 Simple Profile and MPEG-4 part 10 Constrained Baseline Profile. The results validate the following benefits on the MCR of decoders: compact representation, low overhead induced by its compilation, reconfiguration and multi-core abilities.  相似文献   
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For any object L in the category of precrossed modules in Lie algebras PXLie, we construct the object Act(L), which we call the actor of this object. From this construction, we derive the notions of action, center, semidirect product, derivation, commutator, and abelian precrossed module in PXLie. We show that the notion of action is equivalent to the one given in semi-abelian categories, and Act(L) is the split extension classifier for L. In the case of a crossed module in Lie algebras we show how to recover its actor in the category of crossed modules from its actor in the category of precrossed modules.  相似文献   
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Public policy analysts use methods rooted in OR and systems analysis to support policy makers in their judgement. In doing so, most policy analysts recognize the value of a certain understanding of the role of actors in policy making processes. Different methods are available to aid such understanding and, although they all focus on actors, there are important differences between them. Insight into the range of available methods and their characteristics will thus help policy analysts to learn more about the potential and limitations involved in analyzing multi-actor processes. This article provides such an overview, based on the main requirements these methods should meet. This overview is used to discuss some of the implications for policy analysts who are interested in analyzing multi-actor processes, focusing specifically on trade-offs between analytic quality and practical usability.  相似文献   
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