An approach for user’s trajectory prediction based on the trajectory cluster

The existing user’s trajectory prediction methods considered little about the interrelation among users and would fail if the user historical trajectory data were lack. This paper presents a user’s trajectory prediction model and corresponding algorithms by the historical trajectories of users based on the trajectory cluster. The experimental results on MDC dataset show that the proposed method has great improvement in efficiency, accuracy, and scalability comparing with the traditional methods, and it also be applied to the situation where user’s historical trajectory data are lacked.     

Seminar模式实施中课外阅读的养成教育

针对Seminar模式实施中学生在课外阅读存在的问题,有针对性的提出相应的解决方案,并从理论高度指导学生的课外阅读。     

Pre-processing for time domain image formation in SS-BSAR system

A pre-processing procedure is designed for a space-surface bistatic synthetic aperture radar (SS-BSAR) system when a time domain image formation algorithm is employed. Three crucial technical issues relating to the procedure are fully discussed. Firstly, unlike image formation algorithms operating in the frequency domain, a time domain algorithm requires the accurate global navigation satellite system (GNSS) time and position. This paper proposes acquisition of this information using a time-and-spatial transfer with precise ephemeris and interpolation. Secondly, synchronization errors and compensation methods in SS-BSAR are analyzed. Finally, taking the non-ideal factors in the echo and the compatibility of image formation algorithms into account, a matched filter based on the minimum delay is constructed. Experimental result using real data suggest the pre-processing is functioning properly.     

Preparation and performance of dye-sensitized solar cells based on ZnO-modified TiO<Subscript>2</Subscript> electrodes

The ZnO-modified TiO₂ electrode was prepared by adding Zn(CH₃COO)₂·2H₂O to the TiO₂ colloid during the sol-gel production process, and was used in dye-sensitized solar cells (DSCs). The open circuit voltage (V _OC) and fill factor (ff) of the cells were improved significantly. The performances of the ZnO-modified TiO₂ electrode such as dark current, transient photocurrent, impedance, absorption spectra, and flat band potential (V _fb) were investigated. It is found that the interface charge recombination impedance increases and V _fb shifts about 200 mV toward the cathodic potential. The effect mechanism of ZnO modification on the performance of DSCs may be that ZnO occupies the surface states of the TiO₂ film.     

Syntheses,structure and photoluminescent properties of lanthanide oxalatosulfocarboxylate coordination polymers

Hydrothermal reactions of oxalic acid(H2ox) and 2-sulfobenzoic acid(H2L) with lanthanide oxide or hydroxide yielded five lanthanide oxalatosulfocarboxylates.They have a general formula [Ln2L2(ox)(H2O)6]n[Ln = La(1),Nd(2),Eu(3),Gd(4),Tb(5)].Their structures were characterized by single crystal X-ray diffraction,powder X-ray diffraction(PXRD),infrared(IR) spectroscopy,elemental analysis(EA),and thermogravimetric analysis(TGA).1-5 are isostructural coordination polymers and feature one-dimensional(1D) chains,which are extended into 3D supramolecular frameworks through inter-chain hydrogen bonds between coordinated H2O donors and oxygen acceptors from carboxylate,sulfonate and oxalate groups.In addition,the solid-state photoluminescence properties of the Nd(2),Eu(3) and Tb(5) derivatives have been measured at room temperature.The Eu and Tb-containing coordination polymers(CPs) exhibit intense red and green luminescence emissions,respectively,with lifetimes in the order of millisecond.     

考虑蒙皮效应的高层结构有限元分析

文章将蒙皮效应引入高层钢结构的计算分析中 ,对结构各组成部分进行有限元分析。在分析过程中将压型钢板等价为正交各向异性平板 ,并对其引入壳体概念。在推导单元刚度矩阵时 ,着重阐述了压型钢板等效剪切模量的形成。最后通过算例 ,将计算结果与参考结果相比较 ,充分验证了蒙皮效应在高层结构中可有效控制建筑物的侧移     

FTIR光谱仪定镜准直误差分析及动态校正

通过对动镜倾斜时迈克尔逊干涉仪系统模型的理论分析,建立了干涉仪动镜与定镜的非准直状态下干涉光强分布的二维数学模型.得出干涉函数,进而得知动镜与定镜相对倾斜对干涉图的影响.从调制度和相位误差两方面对因动镜倾斜造成的准直误差进行了理论分析,得到各值最大误差容限的计算方法.最后提出实际定镜动态准直校正系统的参考激光干涉和定镜姿态控制系统的实现方案,并推导出动镜和定镜相对倾斜角度的理论计算方法.     

发动机瞬态油耗测量系统研制

介绍以W77C32单片机为核心的发动机瞬态油耗测量系统的主要特点、功能、技术指标、硬软件组成，并分析该系统的误差，该系统不仅测量柴油机发动机的瞬诚油耗和转速，而且可定时间或定质量测量发支机的稳态油耗。     

外翅片管加工时飞边的形成机理

建立了挤压犁削加工外翅片管过程中的飞边的生成模型，给出了产生飞边的判定准则，并对影响飞边产生的因素进行了研究，理论分析及实验结果表明，当刀具挤压挤起的金属边脊的体积大于顶刃切出的翅片体积时，会形成飞边而失稳，反之，则挤压犁削过程稳定，无飞边产生。     

基于Agent技术的企业业务过程管理系统

以三峡工程的物资供应部门为背景，设计了一个基于MAS的企业业务过程管理系统，系统的核心服务合同，反映了Agent的信念，目标，意图，规划，能力和承诺等思维态度，系统的运行通过服务合同的生命周期过程来实现，较好地解决了传统企业管理信息系统难以适应业务模式变化的问题。