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1.
In this paper, the optimal synchronization controller design problem for complex dynamical networks with unknown system internal dynamics is studied. A necessary and sufficient condition on the existence of the optimal control minimizing a quadratic performance index is given. The optimal control law consists of a feedback control and a compensated feedforward control, and the feedback control gain can be obtained by solving the well-known Algebraic Riccati Equation (ARE). Especially, in the presence of unknown system dynamics, a novel adaptive iterative algorithm using the information of system states and inputs is proposed to solve the ARE to get the optimal feedback control gain. Finally, a simulation example shows the effectiveness of the theoretical results.  相似文献   
2.
针对重庆市308位参与精准扶贫活动的科技特派员的调查数据,建立结构方程模型探讨科技特派员的胜任力特征对精准扶贫过程中帮扶效果的影响关系。研究得出:科技特派员的胜任力模型包括思想意识、工作技能、指导帮扶能力、创业帮扶能力四个维度19项指标。科技特派员的思想意识对其创业帮扶能力具有较强的积极影响,工作技能对其指导帮扶能力和创业帮扶能力均具有积极影响,优秀的帮扶能力可以对精准扶贫帮扶效果产生积极作用。因此,应根据该胜任力模型建立提高科技特派员胜任力的培训长效运行机制,完善其在精准扶贫过程中的创业管理体制。  相似文献   
3.
This article presents a multi-lagged-input based data-driven adaptive iterative learning control (M-DDAILC) method for nonlinear multiple-input-multiple-output (MIMO) systems by virtue of multi-lagged-input iterative dynamic linearization (IDL). The original nonlinear and non-affine MIMO system is equivalently transformed into a linear input-output incremental counterpart without loss of dynamics. The proposed learning law utilizes the desired trajectory to cancel the influence from iteration-by-iteration variations, as well as additional multi-lagged inputs to improve control performance. The developed iterative estimation law is more effective and also makes estimation of the unknown parameters easier because the dynamics for each parameter to represent are decreased by dividing the system into multiple components in the multi-lagged-input IDL formulation. Moreover, the proposed M-DDAILC does not need an explicit and accurate model. It is proved to be iteratively convergent with rigorous analysis. Both a numerical example and a practical application to a permanent magnet linear motor are provided to verify the validity and applicability of the proposed method.  相似文献   
4.
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   
5.
ABSTRACT

Research on teacher education, especially on the development of teacher educators, is limited. This paper considers the role of dispositions in the development of pedagogical knowledge (PK) for science teacher educators (STEs), across stages of career. It argues that beliefs and perceptions shift and change along with, but not directly related to, what STEs pay attention to and when they pay attention to it. The eight participants were asked to identify the critical experiences (CEs) of their career that impacted on their development of PK. CEs were analyzed using Morine-Dershimer and Kent’s (1999) model of PK as a framework, but also to identify common emergent themes across participants and common emergent themes for individuals that led to identification of patterns of actions and finally, participant’s dispositions. The notion that beliefs, dispositions and PK are all developed for each individual at their own pace and in their own way is reinforced.  相似文献   
6.
《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   
7.
The relationship between teaching and learning is a most central issue in education research, but it is yet to be fully understood. Variation Theory provides an explanatory account for teaching and learning and offers a specific view on what it means to learn: to discriminate and to discern critical aspects of the object of learning. This paper explores the use of Variation Theory in a case study of two lessons on density in a secondary science classroom. By explicating what was made possible to learn and what was learned this study demonstrates potentials and limitations offered by Variation Theory in enabling a better understanding of the teaching learning relationship.  相似文献   
8.
Entrenched socioeconomic inequalities in achievement have been observed in international assessments for decades, with previous research suggesting that these inequalities may be exacerbated by differentiation in the opportunities provided to various social groups. Much previous research in this field has been US-based or subject to measurement issues. This study investigated socioeconomic inequalities in outcomes and opportunities using four cycles of international assessment data across 78 countries. Further, the paper questions whether inequalities in opportunities are related to inequalities in outcomes. The findings indicate global social inequalities in mathematics and science outcomes, while inequality of opportunity was particularly concentrated in economically advanced countries. Little evidence of the perpetuation of socioeconomic inequality in achievement through differentiated educational provision was found.  相似文献   
9.
通过分析科技管理中的大数据特征,研究大数据对科技管理决策的作用机理.在此基础上,分析大数据驱动高校科技管理决策的要素、关键环节和特点,研究大数据驱动的科技管理决策模型结构,提出大数据驱动科技管理决策是解决高校科技管理高效精准决策的有效办法,最终给出推动大数据驱动高校科技管理决策的建议.  相似文献   
10.
二十一世纪是海洋的世纪。大学生是社会主义的建设者和接班人,有责任和义务推进我国的海洋强国建设。“海洋科学导论”涵盖海洋科学主要分支学科的基本内容,有利于快速提高大学生的海洋意识。针对非海洋科学专业学生学习“海洋科学导论”以及教师授课过程中遇到的问题展开讨论,结合实例提出了相应的教学改革建议,有助于提高学生的学习热情,使学生更深刻地理解海洋学理论,进而更好地将其应用到自己的专业领域。  相似文献   
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