基于灰度图像边缘提取的建筑外形尺寸测量方法

目前建筑施工测绘存在效率低下的问题。通过对目标图像进行灰度变换,以及包括图像校正、对比度展宽、灰度窗切片等图像处理方法对摄像机采集到的建筑外形目标图像边缘进行提取,从而获取目标结构的外形尺寸信息这一方法,可以有效解决该问题并且提升建筑结构检验的工作效率。MATLAB仿真实验结果表明这一方法取得了令人较为满意的结果。     

图像增强算法及实现研究探讨

本文着重对图像增强方法中的灰度变换、直方图均衡化进行了深入的研究,针对增强过程中遇到的一些问题,提出了相应的解决方法。对于分段线性变换方法中如何划分规划灰度区间进行变换这一关键问题,给出了基于区域分割的分段线性变换方法,加快了调整灰度区间的过程,提高了算法的执行效率。通过调整直方图均衡化后像素的灰度值,给出了保留灰度级的直方图均衡化方法,丰富了图像的灰度层次,一定程度上消除了灰阶合并现象对图像带来的影响。实验表明,本文给出的图像增强方法对于一些图像取得了比现有的一些增强方法更好的增强效果。     

大型场景内一种目标对象空间定位方法

大型场景内目标对象空间定位成为近年来的研究热点,其重要任务是对目标对象的精确定位,方便工作人员及时找到目标,甚至跟踪目标对象。在实际工程中,由于费用或监控场景太大等问题,很难实时地监控跟踪目标对象。本文提出在大型场景内一种目标对象空间定位方法,该方法在大型场景内使用多台普通摄像机,通过控制点信息,间接地建立图像坐标系和世界坐标系之间的转换关系,在某种程度上实现目标对象的空间定位。     

浅析内浮顶罐浮盘和密封形式发展趋势

本文介绍并分析了石化行业内浮顶罐常见浮盘和边缘密封形式及其优缺点,得出了全接液浮盘和全补偿边缘密封技术组合优于普通浮盘和普通边缘密封组合这一结论,提出了全接液浮盘和全补偿密封密封组合是未来行业发展的趋势论断。     

一种智能定位大型场景内目标对象的方法

近年来,基于单幅图像的空间定位技术扮演着重要角色,它给人们生活带来方便,但是其应用场景往往只是监控场所一角落。为此,本文提出在一监控场所内对任意目标空间定位。在忽略图像畸变变形,本方法几乎同一时间内,使用多台数码相机对一大型监控场所内获取不同角度图像,建立双灭点透视校正模型,再将其拼接成一幅全景图,通过控制点坐标信息,间接地建立图像坐标系和世界坐标系之间的转换关系,实验结果表明,该方法在一定程度上实现了对大型监控场所内目标的智能定位。     

差分盒维法在焊缝边缘检测上的应用研究

提出了利用分形几何的盒子维数检测焊缝图像边缘的方法,分析并比较了各种计算盒子维数方法的优缺点,利用焊缝X射线图像进行实验,结果证明差分盒维法(DBC)检测焊缝边缘效果较好,能得到单一、连续的焊缝边缘和其内包含的缺陷边缘。     

基于最优梯度估计及小波变换的图象边缘检测技术

基于信号在不同尺度下小波变换系数模不同的变化特征，结合最优梯度估计算法提出了 种边缘检测方法，实验结果说明这种边缘提取方法可以较准确地提取出有较大噪声的图象的边缘。     

主调门内漏缺陷原因分析与处理

针对发电机组主调门内漏缺陷,通过排查确认阀芯回座自定位能力差为内漏原因,并提出多项改进措施,最终消除内漏缺陷。     

海底管道机器人定位信号传播特性实验研究

针对双层海底管道机器人定位的需要,提出了一种基于低频电磁信号的管道内机器人的定位方法.研制了低频电磁发射器和电磁信号接收器,通过仿真分析的方法,分析了电磁信号强度在空间的衰减规律,并据此搭建实验系统,对穿透双层金属管道、海水以及空气3种介质后的信号强度分别进行了实验研究.实验结果表明,电磁信号穿过双层金属管道后有效接收...     

16位位图的灰度化处理方法

灰度化处理是图像处理中很重要的一步,它的结果是后续处理的基础。本文首先介绍了位图的基本结构和色彩系统,然后,着重介绍了十六位位图的灰度化处理方法。     

对三柱体绕流流场和压力场的研究

采用边界元方法对三柱体绕流问题进行了研究,得到了速度场、内点的压力场及边界的压力分布；为了提高计算的精度,在边界积分离散化时采用线单元法,并用混合单元法对边界角点进行了处理, 计算表明结果是合理的。     

Effective technology and design teaching: getting it right in the classroom

Technology and design was added to the Northern Ireland curriculum in September 1992 and through it, teachers seek to address the need for pupils to understand the ever-changing man-made world by developing skills and understanding in its four elements of designing, communicating, manufacturing and the use of energy and control. To be effective in attaining these goals, it is important that teachers allow pupils to have a voice in their learning. They should do this by taking account of pupil responses to the tasks they issue and using those responses as a basis for making choices about instruction and support strategies. This is particularly important in technology and design as pupils need to interpret instructions in light of their design ideas. This paper outlines how three case studies of technology and design teaching were used to identify a range of teaching and learning strategies and evaluate them for their potential to create a learning dialogue with pupils. Drawing on aspects of the effective teaching debate, this learning dialogue was then applied to how teachers exploited pupil histories, managed a range of collaboration strategies and provided effective task orientation. The case studies were based on observations, interviews and content analysis of work over a complete design-and-make project in each school. The paper outlines three continua for effectiveness in each of the three areas observed. The first continuum shows that teachers need a more individualised view of building on pupil histories, the second outlines a range of strategies for the management of pupil collaboration in learning and the third suggests that pupils need to be orientated into complex tasks in ways that support a progressively increasing level of independence in their thinking.     

Help with solving technological problems in project activities

In France, project activities figure predominantly in technology education. The general idea behind learning based on project activity is to allow the pupil to get involved in the activity in question, with the pupil tackling real situations rather than ones of an abstract nature. But too often, we notice that the pedagogical strategies used by teachers in project activities are not particularly effective from a learning point of view. What must be done in order to render project work in technology teaching genuinely effective? In this article, we make the following suggestion: if specific help, based on the pupil’s level of understanding of the activity relating to technologically based problem solving in project work, is made available by the teacher, then project activity can become much more effective from a learning point of view. By using situations highlighting project activities in the technology teaching domain, we analyse the knowledge used by pupils. We then present the specific help used by the teacher as well as the resulting effects upon student activity. We highlight the fact that if specific help conceived as a result of analysing student activity is put in place, the pupil learns more effectually.     

神华集团煤炭产运销一体化运营模式分析

文章结合分工理论、运输经济学理论以及交易费用理论分别从分工演进、生产性质、交易性质等3个视角对神华集团的煤炭产运销一体化运营模式进行了分析。认为,神华集团煤炭产运销一体化运营属于一种链网组织,在我国经济发展的现阶段,神华集团的链网组织是分工演进的必然结果,并且该组织形式有效降低了生产成本和交易费用。但是,神华集团链网组织与市场之间的边界需要通过权衡内部生产成本与交易费用之和与市场交易费用之间的差异来进行界定。     

基于像素级估计的视频显著性检测

为了减少背景噪声干扰,准确地从复杂视频中提取显著目标,提出一种具有时空一致性的视频显著区域检测算法。将视频帧划分为超像素,以超像素为基本单元提取光流特征,在时空一致性原则指导下动态融合颜色、边界信息和光流特征,获取视频显著图。在此基础上,借助视频帧的细节和区域特征对视频显著图进行细化增强。实验结果表明,算法的准确率[CD*2]召回率曲线在复杂图像数据库中高于传统经典算法,具有足够高的鲁棒性,能够减少相机运动和背景运动以及突变情况对跟踪检测的影响。所提方法能够在各种运动模式下和外观复杂场景中较为完整地提取显著目标,可作为预处理技术,改善目标跟踪、行为检测、视频压缩等的性能。     

School meals and pupil satisfaction. Evidence from Italian primary schools

This paper aims to analyse to what extent pupils value the characteristics of the state school foodservice and identify which variables affect the degree of pupils’ satisfaction with the quality of school meals. A representative sample of 33 state primary schools providing meals was extracted for the metropolitan city of Naples. Two questionnaires were distributed, one to the headteachers concerned and the other to 5th grade pupils (10–11 years old). Information about the catering companies was mainly sourced from the AIDA database. Pupil satisfaction was measured by two key variables: pleasantness of eating at school and food tastiness. Controlling for pupil, family, school, foodservice and catering company characteristics, the paper shows that the catering company size negatively impacts upon pupil satisfaction with the foodservice, whereas the estimated meal average production cost is positively associated with pupil satisfaction. The study could assist city boroughs in devising meal quality indicators to be taken into account in designing competitive tendering.     

浅议基于绩效考核视角的煤炭企业内部控制体系创新

对影响内控运行效率的因素进行了分析,进而提出应当建立基于绩效考核的内部控制指标评价体系,形成激励与惩罚功能并存的约束机制,从根本上提高内控系统运行效率。     

异型钛材金相检测探讨

钛材内部的组织结构对材料性能的影响十分重大。针对异型钛材尺寸小，精度高，内在质量及表面质量要求高的特点，探讨了相应金相样品的制备、化学浸蚀的方法及应该注意的问题，制得了清晰的金相照片，为实现异型钛材生产中的内部质量控制提供了保证。     

甜加糯型鲜食玉米留层加工关键工艺研究

为了最大程度延长并保持甜加糯型鲜食玉米的营养成分和口感,对玉米加工工艺进行研究。首先,确定了需要保留玉米内部2～4片苞叶的加工要求;其次,以冀糯173甜加糯型鲜食玉米为研究对象,掌握了鲜食玉米苞叶包覆状态及其在穗柄上的生长分布规律,提出了先定位切割再利用内外层苞叶附着力的差异去除外层苞叶的加工工艺;然后,在开展鲜食玉米外部形态尺寸测量实验的基础上,设计了一种环状定位结构,并搭建了去苞叶设备;最后,通过合理留层试验对所提出的加工工艺进行了验证。结果表明：先经定位环定位切割穗柄,再经去苞叶设备处理的玉米能够苞叶合理留层2～4片,定位环参数为大内径53 mm、小内径41 mm、接触区8 mm、保护区2 mm、厚度2.5 mm。先定位切割再去除外层苞叶的加工工艺合理可行,能够实现甜加糯型鲜食玉米合理保留内层苞叶的加工目标。鲜食玉米留层加工工艺可为甜加糯型鲜食玉米留层加工生产线的设计和改进提供参考。     

彩色复制中颜色信息传递算法的研究进展

本文深入分析了彩色复制过程中造成阶调失真的主要原因,重点阐述了颜色传递过程中引入误差的影响。将颜色传递过程分解为色域映射和色空间转换两大类算法,首先对色域映射边界的描述以及基于图像的色域映射算法的选择问题进行了分析;对色空间转换常用的三种算法,即多项式回归、神经网络和三维插值等算法进行了对比和分析,并列举了当前这一领域的研究现状和今后的发展方向。