科学技术对经济全球化的作用

作为全球化的先导和基础,经济全球化的趋势不可逆转。科学技术对全球化的作用首先体现在对社会分工协作的推动上,并最终促成了经济全球化。最后,简要介绍了经济全球化对科学技术的影响。     

对XML存取的研究与实现

该文着重研究了XML的索引结构，并对XML数据库的存取提出了自己的观点。构造了对XML这种半结构化文档建立索引和查询时采用的数据结构和算法。     

智能搜索引擎与数字图书馆个性化服务

智能搜索引擎基于知识(概念)层面实行信息检索，以较强的自然语言理解和知识处理能力，表现出良好的个性化信息服务特色。因此，智能搜索引擎应用于数字图书馆个性化服务体系，不仅有效发挥前者数据挖掘、知识发现的功能，同时能较大地加深后者的主动性、智能性优势。     

创业型大学:概念内涵、组织特征与实践路径

创业型大学的诞生和发展,是20世纪末以来世界高等教育领域出现的新趋势.本文首先通过对创业型大学的两种不同研究路径的分析,探讨了"变革式"和"引领式"两种不同创业型大学的概念内涵;在此基础上,本研究从组织目标、组织构成、运行机制、组织文化等维度,对创业型大学的基本特征进行梳理,归纳总结出创业型大学与此前的教学型大学、研究...     

工程领导力要素研究

本文在综述20世纪初以来领导力理论内涵以及演化脉络的基础上,结合当前工程实践中从管理向领导转变的客观需要,提出了工程领导力构成要素V—AIR模型,兼顾了工程领导力普遍性和特殊性特点。本文的研究结果对在创新型国家建设进程中培养21世纪卓越工程领导人才,具有借鉴作用。     

桂林石刻诗歌在景点中的审美特征

从唐代开始,石刻诗歌便出现在桂林的摩崖、岩洞中,成为桂林石刻的重要组成部分。经过不断的发展,石刻诗歌对桂林景点的审美已形成相对稳定、较为一致的评价,其在景点中的审美特征日渐突出。独秀峰＂高耸擎天、拔地而起、一枝独秀＂的形象,叠彩山＂层峦叠锦彩、边陲辋川图＂的特点,虞山＂帝德泽边、百代犹思＂的人文意义都是石刻诗歌集中呈现的特征。     

Optimal ϵ -stealthy attack in cyber-physical systems

This paper is concerned with the optimal stealthy attack problems of cyber-physical system, which is represented as discrete-time linear systems. It is considered that a deceptive attack assumed to be able to hijack and modify the nominal control signals from the controller-actuator channel with the metric of ? -stealthiness. Different from the existing literatures, some optimal attack strategies with objectives such that maintaining a fixed level of stealthiness and achieving the maximized performance degradation are designed under some constraints. It is further derived that the results of ours are more relaxed than some methods proposed before. Finally, some numerical simulations are given to illustrate the validity of the theoretical results.     

Corresponding drivability control and energy control strategy in uninterrupted multi-speed mining trucks

An hybrid uninterrupted multi-speed transmission (HUMST), based on the integration of a planetary gear set and a 3-speed automatic manual transmission (3-AMT), is developed to satisfy the specific performance indexes of mining trucks. The power-split device can alleviate and eliminate the inherent torque interruption of the 3-AMT during gear shift by implementing the designed cooperative shift control strategy which is optimized by quadratic performance index. In order to achieve fast torque coordination while guaranteeing the driving comfort performance, the torque profiles of the power split device and the traction motor are optimized by Linear-quadratic regulator (LQR) algorithm. Dynamic programming (DP) is implemented as a benchmark to demonstrate the maximum fuel efficiency of the proposed HUMST. Because of the high computational cost of optimal control strategies such as DP, an improved real-time control strategy (IRTCS) using modified Gaussian distribution function is proposed to significantly reduce the computing load. As efficiency-oriented energy control strategy would result in frequent gear shifts, to achieve a desirable tradeoff between the overall efficiency and the shift stability, multi-objective genetic algorithm (MGA) is integrated to optimize the overall performance. The detail mathematical and dynamic model shows that the proposed shifting strategy with LQR can effectively suppress shift jerk, and the proposed IRTCS with MGA can reduce shift frequency by 70.78% to improve the drivability, only sacrificing 4.86% of overall efficiency compared to that of DP.     

对广州高校推广街舞运动的必要性研究

街舞是一项全新的体育锻炼项目,最近几年才真正在中国大陆流行起来,已经受到广大青少年人群的追捧。时尚的服装,个性的展示,随意的身体舞动使参加街舞锻炼的广大青少年身心得到更大放松。为了街舞运动在广州高校得到更长远的发展,增加学生对街舞运动锻炼的兴趣。采用文献资料法、问卷访问法、逻辑分析法等研究方法,剖析街舞运动在广州高校推广的必要性,为街舞运动的发展与推动贡献微薄之力。     

基于Single-Pass的网络话题在线聚类方法研究

基于Single-Pass算法思想,研究网络话题的在线聚类方法,以期及时捕捉网络信息的动态变化在分析该方法聚类流程的基础上,重点研究网络动态信息流的文本特征抽取和权重计算方法,以及话题类表示和更新等关键问题,设计实验对比分析不同的标题中特征加权系数、特征权重计算和标准化方法以及话题类向量维度对话题聚类质量和时间效率的影响。