一种局部和全局相结合的光流计算方法

光流场是计算机视觉的一个研究方向,微分法是计算光流场的一个常用方法,它分为全局方法和局部方法,全局方法能够得到100％的致密的光流场,而局部方法大多只能得到稀疏的光流场,但它在噪声情况下具有更好的鲁棒性。本文提出一种局部和全局相结合的方法．首先给出五点光流约束的局部方法,再结合全局方法,计算得到了既致密又 鲁棒的光流场。     

三边测量法的结果稳定性研究

定位技术作为网络应用和服务的支撑技术,是无线传感器网络研究的热点问题之一。其中,三边测量法是定位技术的基础,是构建复杂定位系统的基本模块。本文针对三边测量法最优化过程对迭代初值敏感的问题,对结果的稳定性展开研究,提出一种新的三边测量法的迭代最优化的初值选择算法GICC。对比多种三边测量法的实现技术,GICC算法能够自适应地寻找全局最优解,使得三边测量法通过简单下降法即可得到全局最优解,从而避免陷入局部极小解。通过仿真实验证明该算法能有效保证三边测量法结果的稳定性,即保证三边测量法的结果误差一直保持在较低的水平上,从而显著减小全网定位的误差。     

重金属离子的光学检测方法综述

研究了环境和食品中重金属离子的检测方法。介绍了电化学分析法等非光学检测方法,较深入地分析了原子吸收光谱法、原子荧光光度法、原子发射光谱法、紫外可见分光光度法、表面等离子体共振技术测量法、试纸—光电反射测量法、共振光散射技术测量法以及激光诱导击穿光谱法等光学检测方法,给出了重金属离子检测的研究重点与发展方向。     

局部尺寸在功能公差设计中的应用和替代标注研究

为了更好地运用现行公差标准中局部尺寸的定义进行尺寸公差设计,首先以一种自动上料机构为例介绍了ASME Y14.5和ISO/GPS公差标准中局部尺寸的概念及不同之处,分析了在两个不同标准体系下设定局部尺寸、采用公差原则和附加符号来实现几何功能的差异;随后,以电机轴的几何规范为例,分析了当采用两点测量法无法检测局部尺寸的情况下,在保证几何功能的同时采用几何公差项目进行替代标注,以规避检测局部尺寸。正确理解局部尺寸的概念、相关符号及其检测特点,避免歧义性的标注,对合理保证零件的功能、可装配性和控制制造成本有积极意义。     

微小电阻的测量及提高精度的方法

论述了在微小电阻直流恒流源测量法中获取直流恒流源的两种方法.针对微小电阻精确测量的应用需求,提出了3种提高测量精度的方法:四线制法、比例法、滤波和FFT法.通过对双线测量法的研究,得出了四线制法,四线制测量法减小导线电阻对测量的影响.为了降低恒流源对测量精度的影响,改进直流电流测量法,提出了比例法.滤波与FFT法则有效减小了纹波对测量精度的影响,进一步提高了测量精度.测试结果表明,这3种测量微小电阻的方法,具有精度高、稳定性好等特点.因此可对微小电阻进行精确稳定的测量.     

局部体样条函数法可视化建模的模拟退火途径

局部体样条函数法是当前用于大尺寸散乱体数据可视化建模的主要方法之一，与其它方法相比，它有较高的建模精度，又易于实现，但必须首先解决建模区域的恰当划分，文中提出一个模拟退火算法实现区域的优化划分，解决了这一关键问题，通过实验及与Nielson所得结果的对比，证明了这一途径的有效性，并同时时确定了局部体样条函数法建模的适用范围，最后，利用一个海洋调查数据可视化实例显示了局部体样条函数法的应用潜力。     

基于小波和Otsu法的二维条码图像二值化

针对光照不均或背景十分复杂的情况下,全局阈值法无法正确对二维条码图像进行二值化而局部阈值法又会出现块效应的问题,提出一种基于小波分解和大津法的条码图像二值化方法。利用小波分解获得物体表面光照的近似分布进而消除光照不均的影响,并用大津法对获得的图像二值化。该方法既可以消除光照不均的影响,又可以通过选择合适的小波函数使得物体表面光照的近似分布尽量平滑,避免了局部阈值法出现的块效应。     

基于相关函数的航空发动机自整角机信号测试

根据某型发动机自整角机传感器的工作原理,提出了一种新型的基于相关函数法测量该传感器信号的方法。实验和仿真结果表明:该测量法对信号中的随机干扰噪声有极强的抑制能力;对比传统的硬件测量法,该法克服了相位移动明显、响应速度慢等缺点,误差减小为硬件测量法误差的5. 24%,收到了良好的控制效果。     

关于人工势场法局部极小问题的一种解决方法

利用人工势场法进行移动机器人路径规划是十分有效的,在使用人工势场法进行避障的时候,由于移动机器人对周围环境信息的感知具有局限性,容易导致局部极小问题的出现。针对此问题提出一种基于“沿边行为”的方法,当移动机器人进入局部极小状态时激活该行为,使机器人沿着障碍物的边缘运动,使移动机器人在只感知局部信息的条件下,能迅速地摆脱局部极小的状态。仿真实验表明这种方法是可行的,可以有效地解决移动机器人因获取的环境信息不足而陷入局部极小点。     

关于人工势场法局部极小问题的一种解决方法

利用人工势场法进行移动机器人路径规划是十分有效的，在使用人工势场法进行避障的时候，由于移动机器人对周围环境信息的感知具有局限性，容易导致局部极小问题的出现。针对此问题提出一种基于“沿边行为”的方法，当移动机器人进入局部极小状态时激活该行为，使机器人沿着障碍物的边缘运动，使移动机器人在只感知局部信息的条件下，能迅速地摆脱局部极小的状态。仿真实验表明这种方法是可行的，可以有效地解决移动机器人因获取的环境信息不足而陷入局部极小点。     

SOFTSUSY: A program for calculating supersymmetric spectra

SOFTSUSY is a program which accurately calculates the spectrum of superparticles in the Minimal Supersymmetric Standard Model (MSSM). The program solves the renormalisation group equations with theoretical constraints on soft supersymmetry breaking terms provided by the user. Weak-scale gauge coupling and fermion mass data (including one-loop finite MSSM corrections) are used as a boundary condition, as well as successful radiative electroweak symmetry breaking. The program can also calculate a measure of fine-tuning. The program structure has been designed to easily generalize to extensions of the MSSM . This article serves as a self-contained guide to prospective users, and indicates the conventions and approximations used. Sample results are compared with similar calculations in the literature.     

非智能电池在笔记本电脑中的应用

目前笔记本电脑大多采用智能锂电池,之所以称为智能是因为电池中有一个被称为Gas Gauge的处理器,处理器负责收集及处理电池状态,通过Gas Gauge笔记本电脑可以获取到电池的电量、电压、电流、温度等信息。而笔记本电脑系统除了CPU有处理数据的能力外还有另一颗嵌入式控制器（Embedded Controller）,其拥有一些人机交互及电源管理功能,探讨一种方法能简化电池控制板,省去电池中的Gas Gauge而采用嵌入式控制器来代替其功能。     

Towards Increased Understanding of Open Data Use for Software Development

Information Systems Frontiers - The way open data resources of varied type and volume are used by software applications remains only partly known. In this study, following CRoss-Industry Standard...     

Robust pose estimation

Standard least-squares (LS) methods for pose estimation of objects are sensitive to outliers which can occur due to mismatches. Even a single mismatch can severely distort the estimated pose. This paper describes a least-median of squares (LMedS) approach to estimating pose using point matches. It is both robust (resistant to up to 50% outliers) and efficient (linear in the number of points). The basic algorithm is then extended to improve performance in the presence of two types of noise: 1) type I which perturbs all data values by small amounts (e.g., Gaussian) and 2) type II which can corrupt a few data values by large amounts     

Modified Characteristics Gauge–Uzawa Finite Element Method for Time Dependent Conduction–Convection Problems

In this paper, we give the modified characteristics Gauge–Uzawa finite element method (MCGUFEM) for time dependent conduction–convection problems, which is gotten by combining the modified characteristics finite element method and the Gauge–Uzawa method. The stability analysis and the error analysis, which shows that our method is stable and has optimal convergence order, are given. In order to show the effect of MCGUFEM, some numerical results are presented. From the numerical results, we can see that MCGUFEM can simulate the fluid field, temperature field and pressure field very well, and MCGUFEM works better for high Grashoff number $\kappa $ than GUFEM.     

基于高分辨率遥感影像的城市建筑容积率估算方法研究——以上海市中心城区为例

在总结目前常用的建筑容积率估算方法基础上，以高分辨率遥感影像为数据基础，提出了一种新的、适用于大范围建筑容积率估算的方法——阴影面积法。以上海市中心城区为例，详细阐述了阴影面积法在图像处理软件及GIS技术支撑下的实施方案。对估算中可能产生的问题以及估算精度进行了分析。实验表明：阴影面积法对大都市区的建筑容积率估算具有速度快、效率高的特点，基本能够满足中尺度大都市空间建设动态监测的需要。     

Bayesian analysis of two dependent 2×2 contingency tables

Bayesian analysis of correlated binary data when individual information is not available is considered. In particular, a binary outcome is measured on the same subjects of two independent groups at two separate occasions (usually time points). The groups are formulated through a binary exposure or a prognostic factor. Interest lies in estimating the association between exposure and outcome over time. Standard methods for this purpose apply on the individual item responses and are insufficient in case these are missing. Moreover it is assumed that the only available information is the marginal 2×2 cross-tabulations between the grouping variable and the response for each occasion. Assuming independent binomial distributions for the two groups, the success probabilities for each occasion as well as the associations between exposure and outcome, based on the corresponding odds ratios, are estimated. In order to deal with the missing information of each item’s response and to estimate the corresponding transition probabilities, a Bayesian procedure is adopted.     

Motion parameters from right angles

We consider the two-frame problem of estimating the motion of a rigid object in 3D from its noisy 2D perspective images. We assume that the object has straight edges meeting at right angles. The typical object is a rectangle, perhaps partly occluded, or a corner of a box. The accuracy of the obtained motion parameters is compared with that obtained from an object defined as a set of points.     

Control of Robotic Vehicles with Actively Articulated Suspensions in Rough Terrain

Future robotic vehicles will perform challenging tasks in rough terrain, such as planetary exploration and military missions. Rovers with actively articulated suspensions can improve rough-terrain mobility by repositioning their center of mass. This paper presents a method to control actively articulated suspensions to enhance rover tipover stability. A stability metric is defined using a quasi-static model, and optimized on-line. The method relies on estimation of wheel-terrain contact angles. An algorithm for estimating wheel-terrain contact angles from simple on-board sensors is developed. Simulation and experimental results are presented for the Jet Propulsion Laboratory Sample Return Rover that show the control method yields substantially improved stability in rough-terrain.     

Perceptual analysis of gray and color scale measurements

Recently, the gamma subcommittee of the International Committee for Display Metrology has adopted various gamma measurement methods in Information Display Measurements Standard. This article describes further tests including perceptual verification of the suggested measurement methods. In order to verify the suggested measurement method, visual assessment has been carried out. The results of visual assessment can be applied to provide gamma distortion threshold values of the suggested metrology in Information Display Measurements Standard.