DNA计算求解连续空间优化问题

首先构造了二进制编码的网络空间,其两个节点连接权的四条边对应到DNA编码,设计了相应的算子起到DNA计算酶的作用,该算法设计使得DNA计算能够求解连续空间优化问题。通过测试函数表明该算法具有较好的收敛速度和稳定性,求解结果非常好。     

中科院声学所知识创新工程项目基于内容分析的中文问答处理算法及系统实现*

提出了一种基于HNC自然语言理解框架下的中文问答处理算法,并在此算法基础上加以系统实现。试验证明,该系统在中等规模常识库基础上效果显著、准确率高。     

Web文本特征选择算法的研究

以向量空间模型作为Web文本的表示方法,结合Web文本的结构特征对向量空间模型中的特征选择算法进行了分析并加以改进。在改进的算法中,体现出了特征词在Web文档结构中的位置信息;引入了信息论中熵的概念,用词的熵函数对权值进行调整,从而更加准确地选取有效的特征词。实验验证了改进算法的可行性和有效性。     

一种虚拟场景控制方法的研究与实现

针对虚拟场景中视点控制和模型控制两种情况,研究了应用二维鼠标和三维输入设备拾取三维对象模型、移动对象模型和在虚拟场景中漫游的方法,提出了一种用二维鼠标拾取三维模型的方法——粗区域判断、最近拾取,并基于Vega视景仿真开发平台和VC++提出了一种基于二维鼠标拾取、三维输入设备移动的虚拟场景控制方法。     

Incompressible Navier–Stokes solutions by a triangular spectral/p element projection method

The application of the fractional step projection method recently proposed by Guermond and Quartapelle to the numerical approximation of unsteady Navier–Stokes solutions by means of a spectral/p element method is considered. In particular we illustrate the second-order pressure correction technique and evaluate its accuracy properties in some test cases. Stability with respect to the compatibility condition between the approximation spaces for velocity and pressure is also addressed. The high (spectral) accuracy in space and the second-order accuracy in time are verified by two simple test cases with analytical solution. A more interesting problem is solved showing the ability of the method to produce very accurate results also for problems in complex geometries.     

一种基于LUV均匀颜色空间的彩色分割方法

本文提出一种通过转换颜色空间和颜色聚类的方法来实现对彩色图像的分割。由于RGB颜色空间是非均匀空间,算法首先把RGB颜色空间转换到LUV均匀颜色空间,然后对颜色进行相似合并,最终由几种颜色表示待分割的图像,从而实现对彩色图像的色彩分割。     

中小山水城市绿地系统塑造城市特色的途径和方法

绿地是形成城市特色的重要组成部分,城市绿地系统与城市自然人文环境相结合是城市特色构建的一个重要方面。中小山水城市绿地系统规划在塑造城市特色方面具有独特的代表性。文章总结了中小山水城市的特色,提出绿地系统塑造城市特色的手法,并且以泾县为例来分析绿地系统塑造中小山水城市特色的手法。首先分析整理城市特色资源,对主要的关键词进行抽取比较,得到主要的城市特色;然后从整体出发为绿地系统定位,通过城市绿地系统结构布局强化城市山水环境;通过绿道体系的构建打造城市特色的展示体系;最后从树种规划的角度出发塑造城市的宣纸之都的城市特色.     

Chance-constrained model predictive control for spacecraft rendezvous with disturbance estimation

A robust Model Predictive Controller (MPC) is used to solve the problem of spacecraft rendezvous, using the Hill-Clohessy-Wiltshire model with additive disturbances and line-of-sight constraints. Since a standard (non-robust) MPC is not able to cope with disturbances, a robust MPC is designed using a chance-constrained approach for robust satisfaction of constraints in a probabilistic sense. Disturbances are modeled as Gaussian allowing for an explicit transformation of the probabilistic constraints into simple algebraic constraints. To estimate the distribution parameters a predictor of disturbances is proposed. Both robust and non-robust MPC control laws are compared using the Monte Carlo method, which shows the superiority of the robust MPC.     

基于关联规则和粗糙集的话题特征提取方法

针对话题分类文本训练集少、主题相似度大的特点,提出一种基于关联规则和粗糙集的话题特征提取方法。在向量空间模型的基础上,采用挖掘关联规则的方式生成规则集与文本主体,通过调节事务主体的最小支持度与最小置信度查找不同颗粒层次的话题,利用粗糙集理论对词语特征与关联特征进行属性约简。实验结果表明,该方法能提取文本集中描述的评论主题,具有较高的话题分类准确率。     

Structure quantitative map in application for AB2X4 system

Structure maps are constructed for AB₂X₄ (A = metal, B = three-valency element and X = O, S, Se, Te) system (>490 compounds). A way to improve the resolution of the maps is proposed. Crystal structure characteristic (symmetry) is represented on a quantitative scale (coordinate axe Z). The 3D structure diagram with approximating integral plane is constructed and a field of high symmetry compounds is specified with ion radii ratio R(A)/R(X) ≈ 0.60–0.85 and R(B)/R(X) ≈ 0.55–0.70.