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排序方式: 共有1893条查询结果,搜索用时 15 毫秒
1.
[目的/意义]作者相似度研究是探测学科知识结构、挖掘潜在合作关系的重要基础。[方法/过程]本文拟构建作者的关键词—文献2模矩阵,通过研究矩阵对应的灰度图像之间的相似性来判定作者相似性,并利用灰色关联理论计算基于合著关系和基于关键词的作者相似度,最后进行实证分析,对比三种作者相似性结果。[结果/结论]实验表明:基于关键词—文献矩阵的作者相似度研究可以减少因作者发文量不同及高频关键词的使用带来的影响,同时可以放大作者间研究内容的差异性与相似性,能较为准确地反映作者的相似度。 相似文献
2.
韩廷俊 《常熟理工学院学报》2020,(3):117-124
《女子世界》是晚清众多女性期刊中的翘楚,其主编丁祖荫始终以敏锐热忱的启蒙眼光和心忧天下的身份自觉,广开稿源,尽力延揽、吸纳和培养优质作者,试图建构一个条修叶贯的稿源系统和一支相对稳定且素质较高的作者队伍;其中蕴含的现代编辑理念,不仅在晚清报刊发展中具有一定的先锋意义,而且对于当下中国报刊业的发展也具有重要的启示价值。 相似文献
3.
Evaluation of fault diagnosability for networked control systems subject to missing measurements 总被引:1,自引:0,他引:1
The evaluation of fault diagnosability for networked control systems subject to missing measurements is addressed in this paper. In particular, the missing probability is assumed to be affected by norm-bounded uncertainties. By considering noise and missing measurements, the quantitative diagnosability problem is investigated via the principle of weight. To quantify the effect of uncertain missing probabilities, an interval criterion is presented and uncertainty ratio is defined. Furthermore, a novel method is proposed to alleviate the computation task of evaluating fault diagnosability. The effectiveness of the proposed method is verified by a numerical example. 相似文献
4.
Shubham Goel Ravinder Kumar Munish Kumar Vikram Chopra 《Information processing & management》2019,56(3):1053-1066
In the whole world, the internet is exercised by millions of people every day for information retrieval. Even for a small to smaller task like fixing a fan, to cook food or even to iron clothes persons opt to search the web. To fulfill the information needs of people, there are billions of web pages, each having a different degree of relevance to the topic of interest (TOI), scattered throughout the web but this huge size makes manual information retrieval impossible. The page ranking algorithm is an integral part of search engines as it arranges web pages associated with a queried TOI in order of their relevance level. It, therefore, plays an important role in regulating the search quality and user experience for information retrieval. PageRank, HITS, and SALSA are well-known page ranking algorithm based on link structure analysis of a seed set, but ranking given by them has not yet been efficient. In this paper, we propose a variant of SALSA to give sNorm(p) for the efficient ranking of web pages. Our approach relies on a p-Norm from Vector Norm family in a novel way for the ranking of web pages as Vector Norms can reduce the impact of low authority weight in hub weight calculation in an efficient way. Our study, then compares the rankings given by PageRank, HITS, SALSA, and sNorm(p) to the same pages in the same query. The effectiveness of the proposed approach over state of the art methods has been shown using performance measurement technique, Mean Reciprocal Rank (MRR), Precision, Mean Average Precision (MAP), Discounted Cumulative Gain (DCG) and Normalized DCG (NDCG). The experimentation is performed on a dataset acquired after pre-processing of the results collected from initial few pages retrieved for a query by the Google search engine. Based on the type and amount of in-hand domain expertise 30 queries are designed. The extensive evaluation and result analysis are performed using MRR, [email protected], MAP, DCG, and NDCG as the performance measuring statistical metrics. Furthermore, results are statistically verified using a significance test. Findings show that our approach outperforms state of the art methods by attaining 0.8666 as MRR value, 0.7957 as MAP value. Thus contributing to the improvement in the ranking of web pages more efficiently as compared to its counterparts. 相似文献
5.
Laure Perrier Erik Blondal Heather MacDonald 《Library & information science research》2018,40(3-4):173-183
Taking on responsibilities in research data management (RDM) has proven to be a significant challenge as libraries have adopted new roles within higher education institutions. A qualitative review using the meta-ethnographic approach was conducted that examined the experiences of academic libraries and provided clarity on contextual influences associated with achievements, as well as illuminating the reasons for deficiencies. Libraries experienced uncertainty around roles and relationships related to RDM yet were recognized positively as a neutral, centralized space within academic institutions. This perception, combined with the current approach of fostering partnerships and collaborations, may prove to be useful for libraries as they strategically consider how best to provide continued support and services in RDM. Understanding the perspectives of academic libraries on how they respond and support the demands related to RDM offers a fuller, more robust insight that is essential for planning and decision-making. 相似文献
6.
Surprisingly little is known about the relationship between perceived work success and information behavior. This study shows that holistic (versus organization-centric) information behavioral preferences are related to interaction and exchange oriented perceptions of the success of work. The findings were drawn from a partial least square structural equation modeling (PLS-SEM) based analysis of the survey data (N?=?305) collected from employees of a large multinational corporation. The findings suggest that holistic information behavior is more strongly related to social measures of success, whereas their association with quantitative measures tends to be lower. From the perspective of information behavior research, the findings suggest that holism seems to be a similar factor to, for instance, task complexity or personality, which influences human information behavior and, for instance, perceptions of relevance. From a practical perspective, the study suggests that the promotion of specific facets of measuring success and patterns of information behavior can be used to influence the orientation of working between centrifugality and openness. 相似文献
7.
Zhipeng Fan Housheng Su Shiming Chen Minghui Yu Jie Ma 《Journal of The Franklin Institute》2019,356(2):1051-1066
This paper addresses the semi-global leader-following coordination problem of general linear multi-agent systems, in which the control input of each agent is steered by aperiodically intermittent saturated actuator. Both the case with only one virtual leader and the case with multiple virtual leaders are discussed. By using multiple Lyapunov stability theory and applying algebraic Riccati equation-based low-gain feedback technique, sufficient conditions guaranteeing semi-global consensus tracking and semi-global containment tracking are provided. Numerical simulations finally verify the theoretical analysis. 相似文献
8.
This paper investigates the stability and stabilization of switched linear singular systems with state reset at switching instants. Based on the dynamics decomposition of singular subsystems, a sufficient stability condition for the system with the given state reset is obtained. Then, the stabilization problem by state reset is investigated and an algorithm for computing the reset matrices is presented. The obtained results extend some previous works on both singular switched systems and reset control for normal switched systems. Finally, a numerical example is presented to illustrate the effectiveness of the proposed approach. 相似文献
9.
10.
Liang Liu Shengyuan Xu Xue-Jun Xie Bing Xiao 《Journal of The Franklin Institute》2019,356(16):9627-9645
This paper investigates the problem of observer-based decentralized control for a class of large-scale stochastic high-order feedforward systems with multi time delays. By using the homogeneous domination idea and constructing the implementable observer, the decentralized output-feedback controller design scheme is firstly proposed. Then, with the aid of stochastic time delay system stability theory, the globally asymptotically stable in probability of the closed-loop system is verified by selecting an appropriate Lyapunov–Krasoviskii functional. Finally, an example is provided to demonstrate the efficiency of the proposed design method. 相似文献