基于VRML的三维虚拟场景的构建与优化

本文对基于VRML的虚拟场景的设计与实现进行了研究,并从减少文件长度,提高渲染速度两方面提出了优化场景的方法。     

强$J$-Semiclean环

We in this note introduce a new concept, so called strongly J-semiclean ring, that is a generalization of strongly J-clean rings. We first observe the basic properties of strongly J-semiclean rings, constructing typical examples. We next investigate conditions on a local ring R that imply that the upper triangular matrix ring T_n(R) is a strongly J-semiclean ring. Also,the criteria on strong J-semicleanness of 2 × 2 matrices in terms of a quadratic equation are given. As a consequence, several known results relating to strongly J-clean rings are extended to a more general setting.     

将生产资料分类的社会扩大再生产图解法

运用空间解析几何的作图方法,直观并且简便地获得将生产资料分类的社会扩大再生产的解,以及有解的充分必要条件.     

浅谈排列组合中的分书问题

引例1停车场上有7个空位,3辆车去停,有几种方法？     

超声拉拔振动系统研究

根据传统解析法、四端网络和有限元分析法综合设计了超声拉拔振动系统,利用有限元软件ANSYS对振动系统进行了模态分析和谐响应分析,得到了振动系统的振型、谐振频率和振幅放大系数。利用阻抗分析仪和工具显微镜对振动系统进行了测试。实验结果表明,理论设计、分析与实际情况符合良好,且此振动系统在超声拉拔实验中正常工作。     

基于知识图谱的西藏旅游问答系统设计与实现

针对传统搜索引擎无法仅凭关键字准确理解用户意图的问题,构建了基于知识图谱的问答系统,问答系统主要面向西藏旅游领域。首先通过爬虫技术获取西藏旅游景点数据,完成知识图谱的构建。其次,通过bert＿bigru＿crf、bert＿textcnn模型,使系统理解用户问句语义信息。最后,通过构造cypher查询语句返回问答结果。通过语料测试,所构建的系统在回答西藏旅游问题的平均F1值达到了91.74%,实验结果良好,可供相关研究者参考。     

非线性脉冲向量双曲型微分方程解的H-振动性

研究一类具脉冲时滞的非线性双曲型向量泛函微分方程解的H-振动性.方法是采用由Domslak引进的H-振动性的概念,将向量微分方程解的振动问题转化为纯量微分不等式正解和负解的不存在性问题.得到了解的H-振动性的若干判别准则.     

The stability of a non-extensive relativistic Fermi system

Based on the statistical theory of non-extensive relativity,and using theoretical analysis and numerical simulation,the non-extensive mechanical stability of ultra-relativistic free Fermi gas is investigated.The expressions of the stability conditions under high and low temperatures are given,and the mechanisms of the influences of temperature,ultrarelativistic effect,and non-extensive parameter q on stability are analysed.Our results show that at high temperature and under the condition of q < 1,the stability of a non-extensive system is weaker than that of an extensive system,and the relativistic effect reduces system stability as compared with a non-relativistic system.However,under the condition of q > 1,the stability of the non-extensive system is stronger than that of the extensive system,and the relativistic effect strengthens the system stability as compared with the non-relativistic system.In addition,under the condition of low temperature,the variation of the stability of the non-extensive system with temperature has a turning point.