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61.
《Medical reference services quarterly》2013,32(2):87-92
No abstract available for this article. 相似文献
62.
科技期刊的稿件处理结果是否实行反馈进行了长期的探索和研究,分析了实现反馈的可能性,指出了稿件处理意见实行反馈的积极意义,得出了在目前科技高速发展的情况下,科技期刊的稿件处理该实行反馈的结论。最后简要介绍了实施反馈的一些做法。 相似文献
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64.
Recent developments have shown that entity-based models that rely on information from the knowledge graph can improve document retrieval performance. However, given the non-transitive nature of relatedness between entities on the knowledge graph, the use of semantic relatedness measures can lead to topic drift. To address this issue, we propose a relevance-based model for entity selection based on pseudo-relevance feedback, which is then used to systematically expand the input query leading to improved retrieval performance. We perform our experiments on the widely used TREC Web corpora and empirically show that our proposed approach to entity selection significantly improves ad hoc document retrieval compared to strong baselines. More concretely, the contributions of this work are as follows: (1) We introduce a graphical probability model that captures dependencies between entities within the query and documents. (2) We propose an unsupervised entity selection method based on the graphical model for query entity expansion and then for ad hoc retrieval. (3) We thoroughly evaluate our method and compare it with the state-of-the-art keyword and entity based retrieval methods. We demonstrate that the proposed retrieval model shows improved performance over all the other baselines on ClueWeb09B and ClueWeb12B, two widely used Web corpora, on the [email protected], and [email protected] metrics. We also show that the proposed method is most effective on the difficult queries. In addition, We compare our proposed entity selection with a state-of-the-art entity selection technique within the context of ad hoc retrieval using a basic query expansion method and illustrate that it provides more effective retrieval for all expansion weights and different number of expansion entities. 相似文献
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66.
Dylan Poulsen Michael Defoort Mohamed Djemai 《Journal of The Franklin Institute》2019,356(16):9076-9094
We consider the leader–follower consensus problem for a multi-agent system where information is exchanged only on a non-uniform discrete stochastic time domain. For a second-order multi-agent system subject to intermittent information exchange, we model the tracking error dynamics as a varying linear system on a discrete stochastic time scale, where μ is the graininess operator. Based on a Lyapunov operator and a positive perturbation operator on the space of symmetric matrices, we derive necessary and sufficient conditions to design a decentralized consensus protocol. This protocol allows us to cast the mean-square exponential consensus problem within the framework of dynamic equations on stochastic time scales. We establish some theoretical results which allow for the computation of the control gain matrix which guarantees the mean-square exponential stability with a given decay rate for the error dynamics. To show the effectiveness of the theoretical results, some simulation and experimental results on multi-robot systems have been performed. 相似文献
67.
Marcelo Menezes Morato Manh Quan Nguyen Olivier Sename Luc Dugard 《Journal of The Franklin Institute》2019,356(3):1196-1224
This article is concerned with the control of a Semi-Active suspension system of a 7DOF Full Vehicle model, equipped with four Electro Rheological (ER) dampers, taking into account their incipient dissipativity constraints. Herein, a real-time, fast, advanced control structure is presented within the Model Predictive Control framework for Linear Parameter Varying (LPV) systems. The control algorithm is developed to provide a suitable trade-off between comfort and handling performances of the vehicle in a very limited sampling period (), in view of a possible realtime implementation on a real vehicle. The control structure is tested and compared to other standard fast control approaches. Full nonlinear realistic simulation results illustrate the overall good operation and behaviour of the proposed control approach. 相似文献
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黄滔 《四川教育学院学报》2011,(10):92-95
对学生演讲稿的写作过程及成稿文本研究和分析表明,学生演讲中存在清晰的隐含作者。由于演讲是一种公共传播行为,学生演讲中的隐含作者与媒体叙事中的隐含作者较为相似,表现为更优秀、更强大的“第二自我”和文本所体现的、同时也是环境和社会意识形态所要求的价值观和道德观这两个层次。真实作者(学生)与隐含作者的互动、互融过程,就是学生进步、提高的过程。在演讲教学中正确运用隐含作者的作用,将对学生成长产生深远的积极作用。 相似文献
70.
通过分析和研究《西安科技大学学报》创办特色栏目的条件及实践,探讨用特色栏目凸显高校学报的鲜明特征。研究认为:学科优势是特色栏目发展的决定性条件,专家优势是特色栏目发展的核心,稳定的作者群是特色栏目发展的必备条件。同时,高校学报依靠高校的学术优势和区位优势,确立特色栏目、吸纳优质稿件、吸引校外优质作者群,用特色栏目打造期刊的鲜明个性。高校学报特色栏目的发展模式,不仅可以为同类学报的特色发展提供经验,还可以为不同类型的学术期刊提供借鉴。 相似文献