Constructing permutation polynomials from piecewise permutations

We present a construction of permutation polynomials over finite fields by using some piecewise permutations. Based on a matrix approach and an interpolation approach, several classes of piecewise permutation polynomials are obtained.     

分子模拟实验课程建设的探索与实践

We put forward the idea of building a molecular simulation experiment course. After two-year teaching practice, we write the experiment textbook which not only covers the classic experimental projects, but also includes the frontier hot issues, and open exploration experiment. This article summarizes the teaching requirements, basic content, assessment methods, the initial achievements made so far and the prospects for the future.     

地方综合性大学化学创新人才培养课程新体系的建设

构建课程新体系和改革教学内容是高等教育改革永恒的主题。本文立足于地方综合性大学的特点,通过构建"四位一体"课程新体系,形成三层次的课程模块,进行多角度、多层面的课程内容改革,为化学创新型人才的培养奠定了基础。     

A refined cavity construction algorithm for the conductor‐like screening model

A cavity construction algorithm based on the triangulation of an iso‐surface is introduced as a new standard for dielectric continuum solvation calculations with the Conductor‐like Screening Model COSMO. It overcomes deficiencies which have become apparent for the original COSMO standard cavity, especially in concave regions of the molecular shaped cavity. The new standard, called FINE Cavity, is described in this article with several application examples. The earlier COSMO cavity construction algorithms are described for comparison. © 2018 Wiley Periodicals, Inc.     

A quantum similarity matrix (QSM) Aufbau procedure

An Aufbau recursive algorithm, leading to the construction of molecular Quantum similarity matrices (QSM) with positive definite structure is described. As a consequence, Molecular Quantum Similarity measures optimization has to be restricted by a recursive constraint, related to the Euclidian norm of the QSM column elements in Quantum Object density tag reciprocal space.     

几种建筑材料的氡射气系数研究

通过天然γ能谱测量方法测定建材样品中的镭含量,计算理论上衰变产生的氡密度,以及用硫化锌闪烁法测定由样品释放到空气中的氡密度的方法来计算氡的射气系数。通过改变样品的颗粒度大小,以及改变样品的灼烧温度等条件,来研究氡射气系数的变化规律。结果表明,土坯砖射气系数在8.5%~29.4%,红砖射气系数在0.031%~3.5%之间,瓷砖射气系数在0.74%~4.5%之间;建筑材料的氡射气系数随着其自身颗粒度的增大而减小,随加工(灼烧)温度升高而减小。     

On optimal modularity for system construction

Modularity is a natural instrument and a ubiquitous practice for the engineering of human‐made systems. However, modularization remains more of an art than a science; to the extent that the notion of optimal modularity is rarely used in engineering design. We prove that optimal modularity exists (at least for construction)—and is achieved through balanced modularization as structural symmetry in the distribution of the sizes of modules. We show that system construction cost is highly sensitive to both the number of modules and the modularization structure. However, this sensitivity has an inverse relationship with process capability and is minimal for highly capable construction processes with small process uncertainties. Conclusions are reached by a Bayesian estimation technique for a relatively simple construction model originally introduced by Herbert Simon for the hypothetical production of a linear structure, taking into account errors that may occur in the work associated with the production of the links between the nodes in the structure for varied numbers of modules. © 2015 Wiley Periodicals, Inc. Complexity 21: 176–189, 2016     

基于主成分分析的建筑工程成本影响因素分析

影响建筑工程成本的因素众多,这些因素在某种程度上是相关联的,甚至有些是冗余的.运用主成分分析法对影响建筑工程成本的因素进行归纳分析,将影响建筑工程成本17个因素通过主成分分析用5个主成分表示并构造出影响建筑工程成本的主成分综合评价函数,使在工程成本领域多维指标实现综合分析得以实现,为建筑工程成本的研究提供参考.     

面向成本-收益好的无标度耦合网络构建方法

较大平均路径长度的网络会带来较大的网络延迟, 难以支持时间敏感业务与应用. 通过增加连接可以降低源和目的节点之间的跳数, 进而降低网络平均延迟, 使得更加快速地传播信息, 但是增加连接的同时也增加了网络构建成本. 分层网络是研究网络耦合的一个有效方法, 但目前网络构建过程中将每层网络分别处理并认为每层网络之间没有强相关性. 本文提出了一种面向成本-收益的无标度网络动态构建方法. 此方法将网络分为多层, 基于连续论在高层网络中添加连接, 使得网络演化为无标度网络. 此连续过程包括节点度增加过程和局部网络半径增长两个连续过程, 在增加连接的过程中引入表征网络构建成本和收益的成本-收益指标. 模拟结果表明引入成本-收益指标的无标度耦合网络构建方法能够在合理范围内有效降低网络平均路径长度, 提升网络性能, 并且本文给出了耦合网络的动态业务性能, 通过调整高层网络避免网络拥塞.     

光栅投影轮廓测量的系统标定技术

针对在光栅投影轮廓测量术中系统标定可操作性不强、精度不高的问题进行了全面的分析 ,在此基础上提出一种新的系统结构 ,并推导了物相关系。由于去掉了传统结构的平行和垂直两个约束条件 ,测量系统中摄像机和投影装置可以采取任意相对位置 ,操作十分灵活。对新系统提出了方便实用的标定方法 ,在其中引入了摄像机定标技术。应用该测量系统和标定技术进行实例检测 ,测量结果证明 :与传统方法相比 ,可操作性和检测精度得到了提高