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61.
Animal groups in nature often display an enhanced collective information-processing capacity. It has been speculated that natural selection will tune this response to be optimal, ensuring that the group is reactive while also being robust to noise. Here, we show that this is unlikely to be the case. By using a simple model of decision-making in a dynamic environment, we find that when individuals behave rationally and are subject to selection based on their accuracy, optimality of collective decision-making is not attained. Instead, individuals overly rely on social information and evolve to be too readily influenced by their neighbours. This is due to a classic evolutionary conflict between individual and collective interest. The result is a sub-optimal system that is poised on the cusp of total unresponsiveness. Individuals in the evolved group exhibit delayed reactions to changes in the environment, before responding with rapid, socially reinforced transitions, reminiscent of familiar human and animal social systems (markets, stampedes, fashions, etc.). Our results demonstrate that behaviour of this type may not be pathological, but instead could represent an evolutionary attractor for such collective systems.  相似文献   
62.
论文从硬件设备、软件服务、数据资源和任务调度等几个方面对美国海军在开发构建全舰计算环境基础设施过程中标准化的设计方法进行深入分析。通过采用标准化的计算、显示、存储等硬件资源并进行整合,提升硬件资源的利用效率和共用水平;开发各个层次的公共应用功能软件并形成标准化的服务,将软件和硬件解耦,达到应用与数据分离,使得基于TSCEI的信息化装备的构建更加快速灵活,开放性更好,可扩展性及升级能力大为增强。标准化在 TSCEI的推行和实施中起着至关重要的作用。标准化设计方法对构建我军新型信息基础设施具有较重要的借鉴作用。  相似文献   
63.
WIDESTAR II系统为了更好的满足用户需求,在WIDESTAR系统的基础之上对移动终端、基站设备以及核心网节点进行了再次开发,从而实现了更高的传输速率以及与IMS或其他通用IP技术的灵活兼容。本文中,将首先对WIDESTAR II系统进行简要的介绍与分析,然后,对此系统所采用频谱效率提高方法、IP兼容技术以及时延降低策略等卫星移动通信机制进行研究与验证。  相似文献   
64.
如今我国信息化技术全面发展,尤其对于工程测量工作领域来讲,不管是在工程建设和管理方面都产生不小的支撑引导效用。由此,笔者具体结合如今工程建设信息化测绘核心任何以及设备布置细节,进行结构整体安全管理周期和周边地理空间信息技术发展能效整理解析,试图将工程测量最新发展机遇和技术挑战问题处理完全。希望能够借此为日后一定时期范围内相关工程测量规划主体提供合理指导性建议内容,最终为我国各类工程事业可持续发展前景绽放奠定深刻适应基础。  相似文献   
65.
The objective of this study was to investigate the impact of functional labelling on the consumers acceptability and purchase intentions of blueberry functional beverages (BFB). A 2‐day consumer acceptance test was conducted independently with functional information (n = 60) and without any information (n = 80). The presence of functional labelling did not influence the liking attributes of BFBs (P > 0.05). However, functional information positively affected consumer perception of health‐related perceptions associated with BFBs, such as ‘aiding eye health improvement’ and ‘eye fatigue relief’. Subjects perceived more health‐related perceptions when informed test was conducted. The first‐order effect was observed, in which the degree of the first‐order effect was greater for BFBs that had a thicker mouthfeel. Findings from the results can practically guide product developers and marketers in the functional drink industry by providing the strategy for how to evaluate reformulated functional beverages for the consumer acceptance test by warning a counter‐balanced sample presentation.  相似文献   
66.
论述了现有配电网自动化系统的基本特征、广义特征及发展中遇到的信息系统悖论问题,分析配电网自动化及其信息系统实施的必要条件,针对重庆城乡"二元化"结构提出因地制宜的实现方式和实用化条件,考虑了网络、设备、通道、投资、客户、运维等多方面因素,旨在基于现有理论和经验分析并避免配电网自动化应用中的典型误区。从自动化及相关系统的实施条件、实现方式和实用化等方面进行深入剖析,以新的角度重新认识配电网自动化,对技术、管理和理念等方面问题逐一解析,力图破解配电网自动化领域的信息系统悖论,最终加快实现配电运维水平大幅度提升。  相似文献   
67.
This paper reviews the literature related to the concept of information quality (IQ) in the context of the online environment to understand how it has been conceptualised in the Information Systems (IS) literature, to identify gaps in the literature, and to make recommendations for future research. This study also extends the Information Processing Model (IPM) and proposes a novel dynamic model of online IQ perceptions and impacts. To understand the online IQ construct, an in-depth review of the literature is conducted. Overall, we reviewed 508 journal articles published between 1995 and 2016. This study found that there is a substantial gap in the IS literature in regards to a full understanding of the online IQ construct and its relation with the IPM. More research is needed to understand the way individuals process and respond to online information. Further, although the importance of context in theory development has been emphasised in the literature, very few empirical articles have explored the impact of contextual factors on the IPM as well as perceived online IQ. The findings provide online vendors with important guidelines that should be considered to motivate individuals to acquire more information from their websites that could lead to more satisfied and loyal users.  相似文献   
68.
ABSTRACT

This special issue of Review of Communication presents new offerings of the study of communication, forging present and future humanities. This Introduction engages the six essays in this special issue—which extend and intersect across categories of the humanistic study of communication: communication philosophy and ethics, rhetorical theory, history, pedagogy, criticism, and digital humanities—to explore their contributions in defense of the humanities. Taken together, these essays explore the study of communication as (1) a resource for inquiring and exchanging with concepts, practices, and embodiments of difference, the other, and the posthuman; (2) a means of examining the ontological, epistemological, technological, existential, performative, and ethical implications of our communicative being, our being constituted by symbolic action and mediated exchange in ever-present yet always variant material and affective environments, spaces, and places; (3) a discipline emerging from rhetoric, one of the original liberal arts, yet developing in transdisciplinary ways, transforming the binary of humanities and sciences; (4) a tool for decolonizing knowledge(s); (5) a tool for exploring, critiquing, engaging, and creating with the new media of our digital lives together; (6) a long-standing yet ever inventive method and mode for public humanities; and (7) a praxis of resistance. These essays bring to light what studying communication offers the humanities: a plural, public, reflexive, and ever inventive enterprise for examining being human together on this planet.  相似文献   
69.
Information‐Centric Networking (ICN) has been accepted to overcome some weaknesses of the current Internet architecture, showing that “what is being exchanged” is more important than “who are exchanging information.” Given the inadequate considerations on Quality of Service (QoS) and energy saving in ICN routing, we propose in this paper a routing algorithm to enhance the two aspects. At first, on one hand, Cauchy distribution is used as a fuzzy model to evaluate users' QoS requirements, such as bandwidth, delay, and error rate; on the other hand, we formulate energy saving problem to evaluate the green quality of routing algorithm. Then, we design a link selection approach by considering QoS and energy saving, which belongs to a multi‐objective decision problem resolved by intelligent drops algorithm. Finally, we implement the proposed algorithm and compare it with the famous adaptive forwarding mechanism in terms of some significant metrics, and the experimental results reveal that the proposed algorithm is more efficient.  相似文献   
70.
机载空间激光通信视轴稳定是激光通信链路建立的前提。在视轴稳定平台中应用自抗扰控制方法取得了良好的控制效果,但自抗扰控制需调整参数众多且缺乏规范的调整手段。针对自抗扰控制调参难的问题,本文提出了一种利用双态混沌粒子群算法优化自抗扰控制参数的方法。仿真结果表明,与PSO-PID控制方法相比,该方法具有更快的响应速度,更强的抗干扰能力和更好的鲁棒性。  相似文献   
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