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11.
李超 《科技广场》2014,(6):72-75
本文阐述了无人机在安防监控领域的优势与背景。无人机安防监控系统的构建主要为三个模块:首先介绍了无人机的机体设计与内部系统设计;接着阐述了安防监控后台系统的主要功能,以及无人机如何与后台系统进行无线通信;最后总结了无人机安防监控系统的优势,并提出了该系统目前存在的缺陷与改进方法。  相似文献   
12.
Multi-document discourse parsing aims to automatically identify the relations among textual spans from different texts on the same topic. Recently, with the growing amount of information and the emergence of new technologies that deal with many sources of information, more precise and efficient parsing techniques are required. The most relevant theory to multi-document relationship, Cross-document Structure Theory (CST), has been used for parsing purposes before, though the results had not been satisfactory. CST has received many critics because of its subjectivity, which may lead to low annotation agreement and, consequently, to poor parsing performance. In this work, we propose a refinement of the original CST, which consists in (i) formalizing the relationship definitions, (ii) pruning and combining some relations based on their meaning, and (iii) organizing the relations in a hierarchical structure. The hypothesis for this refinement is that it will lead to better agreement in the annotation and consequently to better parsing results. For this aim, it was built an annotated corpus according to this refinement and it was observed an improvement in the annotation agreement. Based on this corpus, a parser was developed using machine learning techniques and hand-crafted rules. Specifically, hierarchical techniques were used to capture the hierarchical organization of the relations according to the proposed refinement of CST. These two approaches were used to identify the relations among texts spans and to generate multi-document annotation structure. Results outperformed other CST parsers, showing the adequacy of the proposed refinement in the theory.  相似文献   
13.
分析了线切割参数对线切割加工工艺指标的影响,指明了怎样合理选择切割线参数。  相似文献   
14.
INTRODUCTIONCorrectlypinpointingsplicing sitesingenomicDNAsequencesisnotaneasytask ,whichisofgreatimportancetothegenomeannotationandgenefinding .Intronsaregenerallydividedinto3classes,namelycalssI,classIIandcommonnu cleuspre mRNA .IntronofclassIandIIcango…  相似文献   
15.
论文针对图书馆用户流失问题,基于图书馆用户数据,构建用户特征矩阵,利用深度神经网络预测用户流失风险;将存在流失风险的用户作为重点研究对象,根据用户特征,结合S-O-R理论设计图书馆用户流失影响因素模型。采用扎根理论方法设计问卷,提取影响图书馆用户流失的指标因素,并构建结构方程模型进行分析,将技术研究与质性研究相结合,挖掘影响用户流失的核心因素,并在此基础上,构建了图书馆智慧型服务空间设计模型,为图书馆创新服务提供决策支持。  相似文献   
16.
Research and development activities are regarded as one of the most influencing factors of the future of a country. Large investments in research can yield a tremendous outcome in terms of a country’s overall wealth and strength. However, public financial resources of countries are often limited which calls for a wise and targeted investment. Scientific publications are considered as one of the main outputs of research investment. Although the general trend of scientific publications is increasing, a detailed analysis is required to monitor the research trends and assess whether they are in line with the top research priorities of the country. Such focused monitoring can shed light on scientific activities evolution as well as the formation of new research areas, thus helping governments to adjust priorities, if required. But monitoring the output of the funded research manually is not only very expensive and difficult, it is also subjective. Using structural topic models, in this paper we evaluated the trends in academic research performed by federally funded Canadian researchers during the time-frame of 2000–2018, covering more than 140,000 research publications. The proposed approach makes it possible to objectively and systematically monitor research projects, or any other set of documents related to research activities such as funding proposals, at large-scale. Our results confirm the accordance between the performed federally funded research projects and the top research priorities of Canada.  相似文献   
17.
虚拟技术在计算机实验教学中的应用   总被引:1,自引:0,他引:1  
针对当前计算机实验资源缺乏和计算机更新快的问题,提出以虚拟技术构建虚拟机试验平台的解决办法。实践证明,虚拟技术可为实验教学和科研构建一个集约高效的计算机实验平台,以VMware公司的VMware Workstation软件创建的虚拟机是对现有计算机实验资源的有力补充,且可随时更新,符合低碳环保的要求。利用虚拟机可方便开展许多传统实验环境下难以开展的计算机实验教学。  相似文献   
18.
OSPF路由协议是计算机网络技术专业重要的知识点之一,对Windows Server 2003下OSPF路由协议的实现进行了研究,提出了运用虚拟机提供的虚拟平台进行Windows Server 2003下OSPF路由实现教学设计,设计了网络拓扑结构,构建了虚拟网络平台,配置了Windows Server 2003下OSPF路由协议,最终对实训的结果进行了验证.  相似文献   
19.
浙江省普通话水平测试"机助人测"系统,经过几年的运行,发现其有利于节约测试时间,有利于测试员灵活掌握测试节奏,有利于学生测试状态的正常发挥和应试心理的调适;但也存在着测试过程中学生的应试节奏把握不太好,测试员的测试状态和测试水准难以均衡,测试题目和测试系统不够完善等弊端。  相似文献   
20.
有线电视网络采用机卡分离方式实现了基于PCMCIA(Personal Computer Memory Card International Association)技术的条件接收系统。目前基于PCMCIA技术来实现机卡分离的方案可行性最强。本文进行了基于PCMCIA技术公共接口CI(Common Interface)的软件、硬件设计,实现了基于PCMCIA技术的条件接收系统,同时考虑PCMCIA技术在物联网中的运用。  相似文献   
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