Static group synchronization of second-order multi-agent systems via pinning control     

Xiang-Gui Guo  Hong-Jian Li  Jun-Jie Zhao  Wei-Wei Che 《Journal of The Franklin Institute》2019,356(9):4842-4858

This paper investigates the expected static group synchronization problem of the second-order multi-agent systems via pinning control. For directed communication topology with spanning tree, based on Gershgorin disk theorem and the matrix property, a static pinning control protocol with fixed gains is first introduced and some sufficient and necessary static group synchronization criteria are also established. It is worth mentioning that a rigorous proof is also given that only one pinning node is needed to guarantee static group synchronization, which could be inferred that our protocol might be more economical and effective in large scale of multi-agent systems. Then, for weakly connected directed communication topology with nodes of zero in-degree, an adaptive pinning control applied to the node with zero in-degree is also proposed to achieve static group synchronization. Finally, the efficiency of the proposed protocols is verified by two simulation examples.  相似文献   

Output regulation for a class of positive switched systems     

Peng Wang  Dan Ma  Jun Zhao 《Journal of The Franklin Institute》2019,356(8):4513-4529

In this paper, a complete procedure for the study of the output regulation problem is established for a class of positive switched systems utilizing a multiple linear copositive Lyapunov functions scheme. The feature of the developed approach is that each subsystem is not required to has a solution to the problem. Moreover, two types of controllers and switching laws are devised. The first one depends on the state together with the external input and the other depends only the error. The conditions ensuring the solvability of the problem for positive switched systems are presented in the form of linear matrix equations plus linear inequalities under some mild constraints. Two examples are finally given to show the performance of the proposed control strategy.  相似文献   

Dynamics of a stochastic multigroup SIQR epidemic model with standard incidence rates     

Qun Liu  Daqing Jiang  Tasawar Hayat  Ahmed Alsaedi 《Journal of The Franklin Institute》2019,356(5):2960-2993

In this paper, we consider a stochastic multigroup SIQR epidemic model with standard incidence rates. By using the stochastic Lyapunov function method, we establish sufficient conditions for the existence of a stationary distribution of the positive solutions to the model. Then we establish sufficient conditions for extinction of the diseases. A stationary distribution means that all the individuals can be coexistent and persistent in the long term. Finally, some examples and numerical simulations are introduced to illustrate our theoretical results.  相似文献   

Pathogenic organization in science: Division of labor and retractions     

John P. Walsh  You-Na Lee  Li Tang 《Research Policy》2019,48(2):444-461

Science is increasingly a team activity, and the size of the teams has been growing. At the same time, there are concerns about an increasing rate of pathologies in science. The growth of team science suggests the need to look beyond individual-level explanations and focus on organizational structures and institutional contexts to explain pathologies in science. Drawing on the literature on organizational pathologies, we argue that division of labor may be a key factor contributing to pathologies in science. Furthermore, we examine the effects of high-stakes incentives and of institutional corruption as additional predictors of scientific pathologies. Using retractions as an indicator of pathologies, and drawing on a matched sample of 195 retracted papers and 349 paired papers that were not retracted, we develop indicators of the division of labor in the team that produced a paper and find that the rate of retractions is higher as the division of labor increases (net of team size). Additionally, we find that high-stakes incentives and institutional corruption are also associated with increased retractions. We conclude with a discussion of the implications of these findings for science policy, in particular for organizing team science projects.  相似文献   

Methods to account for citation inflation in research evaluation     

《Research Policy》2019,48(7):1855-1865

Quantitative research evaluation requires measures that are transparent, relatively simple, and free of disciplinary and temporal bias. We document and provide a solution to a hitherto unaddressed temporal bias – citation inflation – which arises from the basic fact that scientific publication is steadily growing at roughly 4% per year. Moreover, because the total production of citations grows by a factor of 2 every 12 years, this means that the real value of a citation depends on when it was produced. Consequently, failing to convert nominal citation values into real citation values produces significant mis-measurement of scientific impact. To address this problem, we develop a citation deflator method, outline the steps to generalize and implement it using the Web of Science portal, and analyze a large set of researchers from biology and physics to demonstrate how two common evaluation metrics – total citations and h-index – can differ by a remarkable amount depending on whether the underlying citation counts are deflated or not. In particular, our results show that the scientific impact of prior generations is likely to be significantly underestimated when citations are not deflated, often by 100% or more of the nominal value. Thus, our study points to the need for a systemic overhaul of the counting methods used evaluating citation impact – especially in the case of researchers, journals, and institutions – which can span several decades and thus several doubling periods.  相似文献   

Ethical control of innovation in a globalized and liberal world: Is good science still science?     

《Endeavour》2019,43(4):100709

The independence of science was long seen as of prime importance. This position has become less common today. The perception of scientific research as a public service has led to the opinion that it must be accountable to citizens and produce knowledge and innovation that meet their expectations. Numerous authors have voiced the need for anticipatory ethical control of innovation focusing on the scientific research process. This control is considered as the must-have guarantee for “good science.” The current article attempts to trace the ideological origins of the ethical control of innovation, examines its effectiveness against the challenge of globalization and technology-derived major threats and its compatibility with scientific methodology. It also suggests ways to both regulate the innovation process and preserve the independence of science. On the whole, we conclude that truly effective ethical regulation of innovation, i.e. one that protects the greatest number from its adverse effects, is achieved first and foremost by questioning our liberal economic model and the place given to science in our societies.  相似文献   

Microscopy and literature     

Peter J.F. Harris 《Endeavour》2019,43(3):100695

This article draws attention to literary works which have been influenced by microscopy, or in which microscopy has played a significant role. The work of writers including Jonathan Swift, Voltaire, George Eliot, H. G. Wells and D. H. Lawrence is discussed. In many cases these authors had direct experience of operating microscopes and viewing the wonders of the microscopic world. However, with the increasing separation of the two cultures, recent examples of microscopy in literature are rare.  相似文献   

中国与“一带一路”沿线国家农业科学领域科技合作态势分析     

叶春蕾 《科技管理研究》2019,39(12)

为了全方位地揭示中国与“一带一路”沿线国家在农业科技领域的合作发展态势,本文参考ESI提供的农业科学领域期刊和农业学科高被引文献的百分位数阈值,以Web of Science核心合集中收录的6,658篇中国与“一带一路”沿线国家在农业科学领域合作发表的论文作为数据基础,使用一系列科学计量方法及可视化分析方法,从宏观（国家）、中观（科研机构）以及微观（合作研究内容）三个层次全方位地进行科学计量和可视化分析。研究发现：从国家层面来看,中国在合作关系中占有重要的地位;从合作机构来看,属于中国的科研机构在合作中具有绝对的优势;从合作研究内容来看,不同类型的合作机构,其研究内容有较大的差别。  相似文献   

基于CiteSpace的众包创新研究知识图谱分析     

朱宾欣  马志强 《科技管理研究》2019,39(9)

通过检索Web of Science中有关众包创新的论文,利用知识图谱对该领域的研究现状、发展趋势和当前研究热点进行分析。研究结果表明：(1)以美国为首的西方发达国家是众包创新领域的主要引领国家。我国研究起步稍晚,研究成果数量领先,但高质量文献缺乏;(2)众包创新的研究对象逐渐由众包创新内涵向企业商业模式创新,再向线上众包平台知识交互转变,研究方法从经典的案例分析方法向实证研究转换;(3)众包创新现阶段研究热点方向主要包括众包与开放式创新、众包创新绩效、众包创新社区平台等。  相似文献   

上海与韩国科技创新人才培养政策的比较研究     

李宁 《科技管理研究》2019,(16)

本文通过对上海和韩国现行的主要科技创新人才培养政策进行比较分析,挖掘韩国人才培养政策可借鉴的优势特点,为上海人才培养政策的进一步优化完善提供启示。研究发现,二者在政策对象、政策目标、政策实施和政策评价等方面既有相同之处,也存在一定的差异。上海人才培养政策可以在扩大培养对象范围、优化人才培养模式、构建综合培养体系等方面进一步考虑。  相似文献