惯性、刚性振动出矿机合理振动形态设计理论探讨

简要地讨论了惯性、刚性振动出矿机在三个自由度下运动的解答;并根据实际使用情况,提出了振动出矿机合理振动形态的概念及条件。从理论上导出了求得合理振动形态的设计方法及计算公式。     

Shape design of cerium oxide nanoparticles for enhancement of enzyme mimetic activity in therapeutic applications

Cerium oxide nanoparticles (CONPs), widely used in catalytic applications owing to their robust redox reaction, are now being considered in therapeutic applications based on their enzyme mimetic properties such as catalase and super oxide dismutase (SOD) mimetic activities. In therapeutic applications, the emerging demand for CONPs with low cytotoxicity, high cost efficiency, and high enzyme mimetic capability necessitates the exploration of alternative synthesis and effective material design. This study presents a room temperature aqueous synthesis for low-cost production of shape-selective CONPs without potentially harmful organic substances, and additionally, investigates cell viability and catalase and SOD mimetic activities. This synthesis, at room temperature, produced CONPs with particular planes: {111}/{100} nanopolyhedra, {100} nano/submicron cubes, and {111}/{100} nanorods that grew in [110] longitudinal direction. Enzymatic activity assays indicated that nanopolyhedra with a high concentration of Ce⁴⁺ ions promoted catalase mimetic activity, while nanocubes and nanorods with high Ce³⁺ ion concentrations enhanced SOD mimetic activity. This is the first study indicating that shape and facet configuration design of CONPs, coupled with the retention of dominant, specific Ce valence states, potentiates enzyme mimetic activities. These findings may be utilized for CONP design aimed at enhancing enzyme mimetic activities in therapeutic applications.

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规范化分段线性化算法的改进及其在IBM—PC机上的实现

本文指出文献[5]所提出的非线性电阻网络规范化分段线性化算法的欠缺,並对解的条件和解曲线与算法间的关系方面做了较大的改进,使算法达到实用阶段。作者在 IBM-PC 机上实现了改进后的算法。     

434铀矿床控矿层形态特征与矿体分布的关系

本文依据434铀矿床钻孔资料,运用趋势面分析的方法,对控矿层的形态特征进行了定量模拟研究,指出控矿层形态明显地受基底地貌特征的控制,并且在控矿层中存在一凹洼带(古河道).进一步地研究表明:控矿层的沉积环境为山前冲积扇环境,产于控矿层中的铀矿体其分布严格受凹洼带控制.这对于矿床成因认识和矿床评价工作具有较大意义.     

A Complex View of Barycentric Mappings

Barycentric coordinates are very popular for interpolating data values on polyhedral domains. It has been recently shown that expressing them as complex functions has various advantages when interpolating two‐dimensional data in the plane, and in particular for holomorphic maps. We extend and generalize these results by investigating the complex representation of real‐valued barycentric coordinates, when applied to planar domains. We show how the construction for generating real‐valued barycentric coordinates from a given weight function can be applied to generating complex‐valued coordinates, thus deriving complex expressions for the classical barycentric coordinates: Wachspress, mean value, and discrete harmonic. Furthermore, we show that a complex barycentric map admits the intuitive interpretation as a complex‐weighted combination of edge‐to‐edge similarity transformations, allowing the design of “home‐made” barycentric maps with desirable properties. Thus, using the tools of complex analysis, we provide a methodology for analyzing existing barycentric mappings, as well as designing new ones.     

Acquisition of 2D Shape Models from Scenes with Overlapping Objects using String Matching

In this paper we describe a system that is able to acquire models of 2D shapes from cluttered scenes. The input of the system is a sequence of images, each of which shows an unknown number of overlapping unknown 2D objects. The system identifies matching partial shapes across different images and combines them into complete 2D shape models, thus giving a complete interpretation of the input scenes. The identification of partial shapes is based on string matching, whereas a graph search procedure is used for shape model generation. The system has been fully implemented and tested on images containing parts of a jigsaw puzzle. Received: 20 November 1998?Received in revised form: 24 December 1998?Accepted: 4 January 1999     

Efficient processing of spatial joins with DOT-based indexing

A spatial join is a query that searches for a set of object pairs satisfying a given spatial relationship from a database. It is one of the most costly queries, and thus requires an efficient processing algorithm that fully exploits the features of the underlying spatial indexes. In our earlier work, we devised a fairly effective algorithm for processing spatial joins with double transformation (DOT) indexing, which is one of several spatial indexing schemes. However, the algorithm is restricted to only the one-dimensional cases. In this paper, we extend the algorithm for the two-dimensional cases, which are general in Geographic Information Systems (GIS) applications. We first extend DOT to two-dimensional original space. Next, we propose an efficient algorithm for processing range queries using extended DOT. This algorithm employs the quarter division technique and the tri-quarter division technique devised by analyzing the regularity of the space-filling curve used in DOT. This greatly reduces the number of space transformation operations. We then propose a novel spatial join algorithm based on this range query processing algorithm. In processing a spatial join, we determine the access order of disk pages so that we can minimize the number of disk accesses. We show the superiority of the proposed method by extensive experiments using data sets of various distributions and sizes. The experimental results reveal that the proposed method improves the performance of spatial join processing up to three times in comparison with the widely-used R-tree-based spatial join method.     

非圆曲线的数控处理及程序实现

引用优化设计中一维搜索和黄金分割法,针对数控加工中非圆曲线的处理,给出实用、简洁和新颖的宏程序实现方法,解决在数控系统中求解方程组的问题,是数控用户快速解决相关应用问题的有效手段。     

Grouping parts based on geometrical shapes and manufacturing attributes using a neural network

This paper proposes a new part family classification system (IPFACS: Image Processing and Fuzzy ART based Clustering System), which incorporates image processing techniques and a modified Fuzzy ART neural network algorithm. IPFACS can classify parts based on geometrical shape and manufacturing attributes, simultaneously. With a proper reduction and normalization of an image data through the image processing methods and scaling capability in the modified Fuzzy ART, different types of geometrical shape data and manufacturing attribute data can be simultaneously classified in the same system. IPFACS has been tested for an example set of hypothetical parts. The results show that IPFACS provides a good feasible approach to form part families based on both geometrical shape and manufacturing attributes.     

井点降水计算中关键技术分析

在分析潜水完整井井点系统涌水量计算方法的基础上,分析了确定渗透系数“ Ｋ”和抽水影响半径“ Ｒ”的方法及需要注意的问题,并对环状布置井点系统的水面曲线提出了新的看法。