一维链有机锡配合物[(C5H4N-3-CO2)Sn(CH2Ph)3]n的合成、结构和量子化学

通过吡啶-3-甲酸与双三苄基氧化锡反应,合成三苄基锡吡啶-3-羧酸酯.经IR、1H NMR和元素分析表征.并用X-射线单晶衍射仪测定其晶体结构,属单斜晶系,空间群P2(1)/c,晶胞参数为:a=1.06160(7)nm,b=1.46940(10)nm,c=1.60558(11)nm,β=106.4830(10)°,Z=4,V=2.401.6(3)nm3,Dc=1.422 g·cm-3,F(000)=1040,μ(Mo Kα)=1.086 mm-1.R1=0.0247,ωR2=0.0544.中心锡原子与周围原子形成五配位三角双锥结构,N与Sn之间的弱作用形成一维链配聚合物.经分子结构的量子化学计算,探讨化合物的稳定性、分子轨道能量、原子净电荷布居规律以及一些前沿分子轨道的组成特征.     

苯与羰基钼相互作用的密度泛函研究

用密度泛函理论在B3LYP/LANL2DZ基组水平上自由优化(η~x-C_6H_6)Mo(CO)_n(x=1-6;n=1-5)复合物体系的可能构型及计算相互作用能,探索不同羰基数对复合物稳定性、苯和羰基钼相互作用的影响,并分析苯和羰基钼相互作用的NBO。结论(1)苯以η~6与Mo(CO)_n(n=1-3)配位形成的复合物比较稳定,但η~6配位复合物CO的个数越多,则越不稳定;(2)复合物1、2、3和10中,Mo(CO)_n与苯的相互作用拉动电荷由苯的π键电子向Mo(CO)_n的σ_(Mo-CO)~*键转移,而在复合物7中,苯的π键电子向Mo(CO)_n中Mo的孤对电子轨道d转移。     

链表式区域填充算法在三维油藏模型中的应用

分析不同填充方法的特点,针对传统种子填充算法需要静态分配存储空间而造成空间利用率低和不断进出栈操作浪费时间的问题,对种子填充算法进行改进,提出了采用链表存储且对像素点先着色再入链的新方法。该方法根据实际需求动态的分配空间,减少了空间浪费,避免了一些不必要的操作,解决了计算机对大数据处理时由于内存不足而造成死机或处理时间过长的的问题。此方法应用于大模型油藏模型的高速显示系统,提高了空间利用率,实现了三维油藏模型的快速显示。     

Application of VPRS model with enhanced threshold parameter selection mechanism to automatic stock market forecasting and portfolio selection

This study proposes a technique based upon Fuzzy C-Means (FCM) classification theory and related fuzzy theories for choosing an appropriate value of the Variable Precision Rough Set (VPRS) threshold parameter (β) when applied to the classification of continuous information systems. The VPRS model is then combined with a moving Average Autoregressive Exogenous (ARX) prediction model and Grey Systems theory to create an automatic stock market forecasting and portfolio selection mechanism. In the proposed mechanism, financial data are collected automatically every quarter and are input to an ARX prediction model to forecast the future trends of the collected data over the next quarter or half-year period. The forecast data are then reduced using a GM(1, N) model, classified using a FCM clustering algorithm, and then supplied to a VPRS classification module which selects appropriate investment stocks in accordance with a pre-determined set of decision-making rules. Finally, a grey relational analysis technique is employed to weight the selected stocks in such a way as to maximize the rate of return of the stock portfolio. The validity of the proposed approach is demonstrated using electronic stock data extracted from the financial database maintained by the Taiwan Economic Journal (TEJ). The portfolio results obtained using the proposed hybrid model are compared with those obtained using a Rough Set (RS) selection model. The effects of the number of attributes of the RS lower approximation set and VPRS β-lower approximation set on the classification are systematically examined and compared. Overall, the results show that the proposed stock forecasting and stock selection mechanism not only yields a greater number of selected stocks in the β-lower approximation set than in the RS approximation set, but also yields a greater rate of return.     

基于神经网络的系泊系统主动式截断试验仿真

系泊系统主动式截断试验技术对缆索数值模型的求解速度有着较高的要求,而基于集中质量模型或有限元模型的缆索数值模型在计算时需要在每个时间步内迭代求解,因此求解速度缓慢;为解决此问题,采用神经网络辨识得到缆索上端点与截断点运动的时域等价近似模型;该等价模型在每个时间步内无需迭代求解,因此求解速度快于传统的缆索数值模型;同时利用商软OrcaFlex以及Matlab搭建了系泊系统主动式截断试验的仿真平台,将离线辨识得到的神经网络模型代替集中质量模型对缆索截断点运动进行求解;通过对比截断水深以及全水深下张力以及运动结果,说明了神经网络模型代替传统数值模型进行截断点运动计算的可行性。     

区间互补判断矩阵可接受一致性

对区间互补判断矩阵的一致性进行研究,提出一种新的可接受一致性定义,将不满足可接受一致性的矩阵较容易地修正为可接受一致性矩阵.基于凸组合方法,一族明晰数互补判断矩阵的权重向量可被用来求取可接受一致性区间互补判断矩阵的区间权重,并提出了求取可接受一致性区间互补判断矩阵区间权重向量的算法.数值例子显示了所提出的可接受一致性定义以及算法的可行性和有效性.     

基于荧光机理的光纤温度测量技术的研究

本文对应用于生物医学等领域的非接触荧光式温度检测技术进行了系统的理论及技术实验的研究,采用金属镀膜工艺的微小探头制作技术,利用快速傅立叶变换的方法对荧光信号进行处理.利用荧光光纤温度传感器具有测温准确、分辨率高、动态响应好、抗电磁干扰等特点,解决特殊环境下温度的测量.通过实验选择适合20-70℃温度范围的荧光材料,在此基础上设计荧光光纤温度测量系统.     

分布式打印环境和Internet打印技术

该文阐述了分布式打印环境的概念和特点,并对Ｉｎｔｅｒｎｅｔ打印的思想和技术进行了分析和描述,就ＩＰＰ的设计和实现提供了基本方法。     

Performing permutations on interconnection networks by regularlychanging switch states

In this paper, we present an algorithm for performing permutations of messages on multistage interconnection networks. Permutations of messages are needed in many parallel algorithms. The proposed algorithm is feasible for any networks that can connect each input to each output using a set of N nonblocking connections, where N is the number of ports on the network. Messages are segmented into N submessages that are sent independently in each time step. For any permutation, the settings of switches are changed with fixed patterns. Partitioning of the network into independent subnetworks is also supported, each capable of simultaneously routing a different permutation