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排序方式： 共有9050条查询结果，搜索用时 218 毫秒
1.
In India, more than 276 million children and youth were out of school for extended periods since March 2020 due to school closures in response to COVID-19. A key challenge has been how to measure the impact of responses to continuity of learning both to ensure more effective responses in the event of further disruptions, but also to help the education community conceptualize more creative and effective approaches to learning, through blended and flexible approaches. This study reflects on the findings from a UNICEF survey targeting parents and adolescents across 6 states in India, and identifies lessons learned for addressing learning inequities during future school closures. We focus on measuring three key variables – access to technology, their utilization, and perceived learning for different profiles of children. As students began learning from home, technology access rates in households were initially used to determine the estimated maximum reach of different distance learning modalities during school closures. Beyond access, we find significant variations in adolescents’ use of technology for learning purposes and their perceptions of learning, linked to the type of remote learning modality, gender, location and type of school. We discuss the implications for government strategies and policies to ensure better utilization of technologies which are available in households and to address equity gaps in learning opportunities. 相似文献
2.
在大数据视域下,以档案管理理论和信息系统安全理论为基础,参考国家相关法规及标准,结合档案管理工作实务,研究当下档案管理工作中的风险,在此基础上初步构建起档案安全管理体系,并对可引入该体系的实用技术进行分析。 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
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Extant research on technology acceptance has devoted considerable attention to the relationship between behavioral intention (BI) and system use (SU) over time. However, the empirical results have been mixed—studies have found BI to both influence and not influence SU. Studies that examined the BI→SU relationship have employed different research models and research designs. Prior research models have examined direct effects on SU, indirect effects on SU through BI, the moderator effects on BI→SU, and the mediating role of BI in BI→SU. Studies have employed different types of respondents, information technologies, geographic regions, voluntariness, and measurement designs. This study proposes that such differences in research models and designs contribute to the mixed results for BI→SU, and reports a meta-analysis of findings reported in 113 prior studies along with a critical review of the BI→SU relationship. While no significant differences were found in the results for the BI→SU relationship across various research design characteristics, this study finds that the measurement of SU has been conflated with future and current or past behavior, direct and indirect effects on SU impact BI→SU, BI is modeled to fully and partially mediate the effects of other variables on SU, and moderators for the BI→SU relationship may be necessary. This study identifies several directions for future research and underlines the need to rethink the link between BI and SU. 相似文献
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7.
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
8.
Zhuoyue Song Chao Duan Jianan Wang Qinghe Wu 《Journal of The Franklin Institute》2019,356(2):998-1020
This paper investigates a quaternion-based finite-time cooperative attitude synchronization and tracking of multiple rigid spacecraft with a virtual leader subject to bounded external disturbances. Firstly, the communication network between followers is assumed to be an undirected graph and every follower can get a direct access to the virtual leader, by using two neighborhood attitude error signals, a novel chattering-free recursive full-order sliding mode control algorithm is proposed such that all follower spacecraft synchronize to the virtual leader in finite time. In the proposed algorithm, the sliding mode surface is constructed by two layers of sliding mode surfaces, which are called as the outer and the inner sliding mode surfaces. To achieve finite-time performance of sliding mode dynamics, the outer sliding mode surface is designed as a terminal sliding mode manifold, and the inner one is designed as a fast nonsingular terminal sliding mode manifold, respectively. Then, to reduce the heavy communication burden, a distributed recursive full-order sliding mode control law is designed by introducing a distributed finite-time sliding mode estimator such that only a subset of the group members has access to the virtual leader. Finally, a numerical example is illustrated to demonstrate the validity of the proposed results. 相似文献
9.
This article contributes a conceptual analysis of the power and influence of for- profit philanthropy on educational development during pandemic times. Through highlighting for-profit philanthropy, describing its relevance to educational development, and drawing attention to four aspects that are under-examined as for- profit philanthropists enact their philanthropic agendas in response to the COVID- 19 pandemic, disaster philanthropy is presented as a window of opportunity for elite donors to enact changes in public education based on their distinct donor and institutional agendas. Implications for educational development are discussed including shifts in power, definitions and public vs. private returns. 相似文献
10.
Technology acceptance has spawned considerable research in technology adoption, technology use, and technology switching. However, technology choice—i.e., an individual’s selection of a technology from a set of technologies that support similar tasks—has received limited attention in information systems research. This research was aimed at identifying the drivers of technology choice through a series of activities in two universities, in which students chose an information technology tool from various alternatives to complete the given tasks. A thematic analysis was conducted on the reasons for technology choice reported by 249 students, which yielded 18 technology, user, and environmental drivers that influenced individuals’ technology choice. This study provides insights into the drivers generally applicable for technology choice and drivers applicable in specific contexts. Implications for research and practice are discussed. 相似文献