在普通铣床上镗阶梯孔的铣夹头设计

在机加工过程中经常遇到在普通机床上不好加工的一些表面，需要设计一些简单实用的工艺装备。本文介绍一种在普通铣床上加工阶梯孔专用夹头的设计方法。     

Learning-based summarisation of XML documents

Documents formatted in eXtensible Markup Language (XML) are available in collections of various document types. In this paper, we present an approach for the summarisation of XML documents. The novelty of this approach lies in that it is based on features not only from the content of documents, but also from their logical structure. We follow a machine learning, sentence extraction-based summarisation technique. To find which features are more effective for producing summaries, this approach views sentence extraction as an ordering task. We evaluated our summarisation model using the INEX and SUMMAC datasets. The results demonstrate that the inclusion of features from the logical structure of documents increases the effectiveness of the summariser, and that the learnable system is also effective and well-suited to the task of summarisation in the context of XML documents. Our approach is generic, and is therefore applicable, apart from entire documents, to elements of varying granularity within the XML tree. We view these results as a step towards the intelligent summarisation of XML documents.

浅析高职《机械设计基础》课程设计改革

高职《机械设计基础》课程设计按传统的课程设计方式进行,已不能适应教学改革与发展的需求。采用增加实践环节,变“设计”为“测绘”,变“二维设计”为“三维设计”的方法,可提高课程设计的应用性、实践性,提高教学效果贴近高职教育的需要。     

数控机床之数控系统的诊断与维护

通过对数控机床的构成与特点的概述,进而对数控系统的常见故障进行了分析,并对数控系统的故障诊断与维护方法,以及应注意的事项作了较为详细的阐述。     

相关反馈技术在知识检索中的应用

本文从相关反馈技术的基本原理出发，综合应用信息管理与机器学习，探讨了相关反馈技术在知识检索中的应用模式、相关反馈检索算法和相关反馈学习算法，最后提出了对该领域研究的建议。     

Supervised sentiment analysis in Czech social media

This article describes in-depth research on machine learning methods for sentiment analysis of Czech social media. Whereas in English, Chinese, or Spanish this field has a long history and evaluation datasets for various domains are widely available, in the case of the Czech language no systematic research has yet been conducted. We tackle this issue and establish a common ground for further research by providing a large human-annotated Czech social media corpus. Furthermore, we evaluate state-of-the-art supervised machine learning methods for sentiment analysis. We explore different pre-processing techniques and employ various features and classifiers. We also experiment with five different feature selection algorithms and investigate the influence of named entity recognition and preprocessing on sentiment classification performance. Moreover, in addition to our newly created social media dataset, we also report results for other popular domains, such as movie and product reviews. We believe that this article will not only extend the current sentiment analysis research to another family of languages, but will also encourage competition, potentially leading to the production of high-end commercial solutions.     

选号式双工制架线调频载波机设计

本文介绍一种采用导频、锁相环调频、鉴频等技术来实现选号功能的双工制架线电机车载载波机,总机对15台分机能进行选号通信,解决了异频单工制载波机总机与某一分机通话时其他分机也能听到的缺点,提高了载波电话的通信质量。     

宁夏水资源可持续利用评价研究

本文在吸收前人研究成果的基础上,首先对水资源可持续利用评价指标体系进行了分析,确立了适合宁夏区情的初始指标,其次利用聚类法从初始指标里筛选得到15个评价指标,采用SVM对宁夏2002—2011年的水资源可持续利用状况进行了评价,并与传统的BP-ANN的评价结果加以比较,结果表明:两者评价结论基本一致;与ANN相比,SVM模型简单,泛化性强,分类精度高。该结果对宁夏水资源的调控和分配具有一定的意义。     

软件还原与虚拟机技术在计算机实验教学中的应用

针对计算机实验教学中普遍存在的局限性,提出一种基于软件还原与虚拟机技术的解决方案。利用多种技术有机结合构建实验教学环境,可以开展多门课程的实验教学,并能改善现有教学环境,提高学习和工作效率。     

基于MATLAB的无刷双馈风力发电机的控制策略研究

在传统风力发电的基础上,以作为风力发电机用的无刷双馈电机为主要研究对象,进行了深入的研究,研究了无刷双馈电机的转子侧和网侧PWM变换器的控制策略,建立转子侧和网侧PWM变换器控制策略的结构模型,把功率绕组和控制绕组分别建立在各自的同步坐标系下,分别进行磁场定向和电压定向矢量控制,从而简化了数学模型,获得了适合的控制策略。最后采用Matlab/Simulink仿真软件建立相应的控制系统仿真模型,模拟三种情景,进行仿真实验,分析实验结果。