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加速度计数学模型成员集辨识
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作者 刘西河 《战术导弹控制技术》 1994年第1期27-31,共5页
关键词 加速度计 数学模型 成员集 系统辨识
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基于布隆过滤器的零知识集成员证明效率提升
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作者 杨书鑫 李鹏 《软件工程》 2024年第7期47-51,60,共6页
针对区块链中数据的安全验证问题(数据的动态增加导致零知识集成员证明参数更新频繁、参数生成和验证时间变长),进行了创新性的完善。提出了一种新型的数据存储模型,结合优化的跳表索引,提高了数据验证的安全性和效率。实验结果表明,基... 针对区块链中数据的安全验证问题(数据的动态增加导致零知识集成员证明参数更新频繁、参数生成和验证时间变长),进行了创新性的完善。提出了一种新型的数据存储模型,结合优化的跳表索引,提高了数据验证的安全性和效率。实验结果表明,基于布隆过滤器的新型数据存储模型和外部索引,虽然增加了空间复杂度,但是借助预校验机制,提高了约45%的安全校验速度。此外,优化后的时间跳表总体上提高了约50%的区块检索速度,并且索引更新更加便捷。 展开更多
关键词 区块链 零知识成员证明 数据存储模型 布隆过滤器 跳表
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自适应人工免疫网络算法的无线传感网络拓扑结构优化 被引量:13
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作者 韦运玲 《电子测量技术》 2020年第1期85-89,共5页
无线传感器网络(MWSN)具有动态拓扑的特性,因而节点移动、能量消耗等影响因素会导致传感器网络的寿命。在现有层次型拓扑控制算法的基础上,借鉴adhoc网络层次拓扑生成算法WCA的设计原理,提出一种应用于无线传感器网络的新型层次型拓扑... 无线传感器网络(MWSN)具有动态拓扑的特性,因而节点移动、能量消耗等影响因素会导致传感器网络的寿命。在现有层次型拓扑控制算法的基础上,借鉴adhoc网络层次拓扑生成算法WCA的设计原理,提出一种应用于无线传感器网络的新型层次型拓扑结构优化算法。该算法综合考虑节点的能量和位置状况,为每个节点定义不同的权值,从中选出性能优越的节点担任簇首,同时通过设置节点度参数来确保最优的拓扑结构。同时依托自适应人工免疫网络算法,用于实现MWSNs的目标。仿真结果表明,改进的人工免疫网络算法(KC-AAINA)有助于找到良好的聚类配置和簇头数量,限制了节点能耗,改善了MWSN的网络寿命、能量消耗和分组传输,从而提高网络生命周期。 展开更多
关键词 能耗 簇头 成员 动态拓扑 人工免疫网络
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Interactive Multimodal Narrative as an Approach to Developing Emergent Literacy in Early Childhood Education
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作者 Adila Ferreira Lopes de Faria Paulo Manuel Miranda Faria Maria Altina Silva Ramos 《Sino-US English Teaching》 2013年第4期328-333,共6页
At present, the Portuguese education system promotes the development of new literacies in all education levels in response to new requirements of the digital world which imply changes in children's education. In fact... At present, the Portuguese education system promotes the development of new literacies in all education levels in response to new requirements of the digital world which imply changes in children's education. In fact, reading and writing are no longer limited exclusively to books, rather they are associated with diversified digital media integrating text, sound, image, and video. In this context, we developed an exploratory study in a kindergarten with the children and their family members. Data were collected through participant observation, children conversational interviews, and digital narratives produced by children. Data analysis is based on content analysis with NVivo software support. The emergence of literacy is evident in verbal interactions in peer-group work, in contact with the written text, in "writing" in various media, and in sharing knowledge, discoveries, and digital narratives produced in an online community (http://janelajardim.ning.com). This paper presents: (1) a systematic literature review in the field of digital narrative and emergent literacy; (2) the description of children's activities concerning interactive multimodal narrative; (3) the results of this work; and (4) the conclusion about contribution of multimodal narratives to the emergence of reading, writing, and digital skills 展开更多
关键词 emergent literacy multimodal narrative systematic literature review NVivo
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Optimal operating policy for a controllable queueing model with a fuzzy environment 被引量:3
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作者 Chuen-horng LIN Jau-chuan KE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第2期311-318,共8页
We construct the membership functions of the fuzzy objective values of a controllable queueing model,in which cost elements,arrival rate and service rate are all fuzzy numbers. Based on Zadeh's extension principle... We construct the membership functions of the fuzzy objective values of a controllable queueing model,in which cost elements,arrival rate and service rate are all fuzzy numbers. Based on Zadeh's extension principle,a set of parametric nonlinear programs is developed to find the upper and lower bounds of the minimal average total cost per unit time at the possibility level. The membership functions of the minimal average total cost are further constructed using different values of the possibility level. A numerical example is solved successfully to illustrate the validity of the proposed approach. Because the object value is expressed and governed by the membership functions,the optimization problem in a fuzzy environment for the controllable queueing models is represented more accurately and analytical results are more useful for system designers and practitioners. 展开更多
关键词 Controllable queue Fuzzy sets Membership function Nonlinear programming
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Discovery of eight lensing clusters of galaxies 被引量:2
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作者 LIANG SuMing WEN ZhongLue +1 位作者 HAN JinLin JIANG YunYing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第9期1809-1815,共7页
Clusters of galaxies have a huge mass which can act as gravitational lenses.Galaxies behind clusters can be distorted by the lenses to form arcs in images.Herein a search was done for giant lensed arcs using the SDSS ... Clusters of galaxies have a huge mass which can act as gravitational lenses.Galaxies behind clusters can be distorted by the lenses to form arcs in images.Herein a search was done for giant lensed arcs using the SDSS data.By visually inspecting SDSS images of newly identified clusters in the SDSS DR8 and Stripe 82 data,we discover 8 strong lensing clusters together with additional 3probable and 6 possible cases.The lensed arcs show bluer colors than the member galaxies of clusters.The masses and optical luminosities of galaxy clusters interior to the arcs are calculated.The mass-to-light ratios are found to be in the range of a few tens of M⊙/L⊙,consistent with the distribution of previously known lensing clusters. 展开更多
关键词 galaxy clusters gravitational lenses and luminous arcs photography and photometry
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