基于图像内容自适应矩阵完成的高动态范围成像方法

高动态范围图像合成中容易出现鬼影现象,而传统的矩阵完成算法没有考虑多曝光图像序列的运动特征,导致高动态范围图像中的鬼影未能完全去除。针对这一问题,本文提出一种基于低动态范围图像内容自适应矩阵完成算法以去除高动态范围图像中的鬼影。首先,根据图像的亮度和色度信息,确定低动态范围图像的运动区域;然后根据这一运动先验信息,调整矩阵完成算法过程中的正则化约束强度,从而得到每幅低动态范围图像的背景信息;最后,考虑到不同曝光度的图像在每一区域所包含的细节不同,采用与曝光相关的融合策略合成去鬼影的高动态范围图像。实验分别采用简单背景图像序列和复杂背景图像序列,结果表明,所提出的算法相比于奇异值部分和最小化矩阵完成算法,能取得更好的合成效果,适用于复杂背景下的高动态范围图像合成。     

LIP多重微区域分解算法扩展数字图像动态范围

CCD/CMOS 图像传感器的饱和电流和背景噪音使得一次曝光很难超过 60-80dB 的动态范围。用 LIP(Logarithmic image processing)模式将图像转换为灰色调函数,再将基于 LIP 模式的非线性多重微区域图像分解算法进行改进,可以适应不同亮度的单幅图像处理,提高了可分辨信息量和图像对比度,同时抑止了噪声。质量评价显示,该算法能将 MOS 等级四的源图像提高到等级一。     

The image inpainting algorithm based on pruning samples by referring to four-domains

In order to retrieve large scale damaged image with rich geometry structure and texture information, the novel image inpainting algorithm based on the neighbourhood reference priority can not only maintain image character but also improve image inpainting speed has been proposed in the paper. The problems of an image inpainting process can be translated into the best sample searching process. First, the extracting structure information of image and the dividing sample region into sub-regions server. Second, in order to adjust the neglect of structure of matching method named SSD, introducing structure symmetry matching constraint into matching method, it avoids matching mistakenly and improves sample matching precision and searching efficiency. Then, improving priority equations by bringing in structure weight and confidence, highlighted the effect of structure to inpainting sequence. Finally, computing priority of four-domains neighbour by computation overlapping information between object patch and sample patch, so that referring to secure information of four-domains neighbour, to prune sample dataset and search optimal sample. The experimental results have demonstrated that the proposed algorithm can overcome problems like texture blurring and structure dislocations and so on, the PSNR of the improved algorithm has been increased by 0.5–1?dB comparing other contrast methods while speeding up the image inpainting process, recovered image is much continuous for visuality. Meanwhile, it can recover efficiently common damage images and be more pervasive.     

采用仿射变换的红外与可见光图像配准方法

图像配准是图像融合技术的基本环节和首要问题。针对红外和可见光图像的配准问题,分析了两者配准的特点。引入6参数的仿射变换模型来描述3D空间中的目标,分析了通常采用的4参数模型的不完备性。利用模型计算配准参数,并用最小二乘法达到用多个配准点拟合出最优参数解的目的。实验结果表明,此方法可以很好地消除红外和可见光图像之间的差异。     

Reduced model of discrete‐time dynamic image segmentation system and its bifurcation analysis

We have developed a discrete‐time dynamic image segmentation system consisting of chaotic neurons and a global inhibitor. Our system receives an image with isolated regions and can output segmented images in time series based on oscillatory responses of chaotic neurons. In this article, we derive a reduced model to find intrinsic properties of the system of dynamic image segmentation. Using numerical method for analyzing dynamical systems, we investigated bifurcation phenomena of a fixed point observed in the reduced model. As the results, in a model of two coupled chaotic neurons, we found that a set of Neimark‐Sacker bifurcations causes the generation of an in‐phase oscillatory response, which is unsuitable for the purpose of dynamic image segmentation. The bifurcation analysis gives appropriate parameter values to exclude the generation of in‐phase oscillatory responses, i.e., our dynamic image segmentation system can work well. © 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 283–289, 2009     

基于模态试验与优化的静动力学模型转换

在结构强度分析中,将刚度分布较为准确的静力学模型转换为动力学模型可以大大提高建模效率。提出了一种基于模态试验和优化算法的静、动力学模型转换方法。在调整静力学模型的刚度矩阵基础上,再按照质量、质心、惯矩、单元体积进行节点质量的预分配,最后根据模态试验识别出的模态参数优化节点质量的修正量,如此便可得到其动力学模型。以某飞机翼身组合结构模型的转换为例,证明了该方法的实用性。     

A novel level set method for image segmentation by combining local and global information

A novel level set method integrating local and global statistical information is proposed in this paper. In our method, a new signed pressure force (SPF) function is constructed by two parts. One is the global average intensity of the image, which can accelerate the evolution of the curve when the contour far away from the object boundaries. The other is the intensity average of difference image between the averaging convolution image and the original image, which can guide the evolving curve to catch the boundaries of the objects. In addition, an adaptive weighting function is utilized to adjust the ratio between the global and local terms, which can eliminate the inconvenient selection of weighting parameter. By substituting the new SPF function for the edge stopping function of the geodesic active contour model, we obtain a novel adaptive hybrid segmentation model, which is capable of segmenting the images with intensity inhomogeneity. What is more, in our method, the level set function is initialized with a binary function, which reduces the computational cost for the re-initialization step. The experimental results and comparisons with several popular models on synthetic and real images indicate that our method achieves superior performance in segmenting images with noise, low contrast and intensity inhomogeneity.     

Dynamic image analysis of differently milled talc particles and comparison by various methods

In this study, particle shapes of talc mineral ground by various types of mills were determined using automated dynamic image analyzer by counting averagely 19,000 particles for each mill product. The results were expressed in terms of circularity (C) and bounding rectangle aspect ratio (BRAR). It was concluded that particles created by rod mill had the highest BRAR and the lowest C, while the particles having the highest C and the lowest BRAR were obtained by autogenous milling. The statistical significance of mean shape values of different milled particles was also tested by using one way analysis of variance (ANOVA) and post hoc Tukey test. The ANOVA results showed that there are significant differences among C and BRAR mean values of particles produced by autogenous, ball, and rod mill at 99% level of confidence. The results were in good agreement with the results obtained by other techniques employed previously. Thus, the result of dynamic image analysis (DIA) can be used for quality control of the products of talc mineral as the morphology decides whether specific talc is appropriate for a specific application or not.     

Three-dimensional atomic imaging of Y and (B12)13 clusters in YB56 by HREM and crystallographic image processing

The three-dimensional atomic image of YB₅₆ was obtained by inverse Fourier transformation of three-dimensional phases and amplitudes in three high-resolution images along [100], [110] and [111] of YB₅₆ crystals. After crystallographic image processing, the image directly showed the three-dimensional potential map of the crystal, which showed (B₁₂)₁₃ clusters and Y atom positions. The present method would be useful for three-dimensional structure analysis in nanoscale regions.     

Production management model integrating the principles of lean manufacturing and sustainability supported by the cultural transformation of a company

The search for superior production performance has been used by companies to overcome competition in the current global economic scenario. Efficient manufacturing connected to environmental initiatives provides a company with favourable conditions for maintaining uniform and continuous improvement in its competitive performance, while providing operational versatility to respond quickly to volatile markets. As production is one of the most expensive areas for a company, many organisations have sought a new management model for their production system that provides substantial productivity gains, cost saving opportunities and higher customer satisfaction. This study proposes a model of production management and an implementation method integrating the principles of lean manufacturing and sustainability, supported by cultural transformation at the company. Its objective was to achieve productivity gains and improvements on customer satisfaction, as well as develop the ability to provide quick responses to market changes in a globalised economy. The implementation of the proposed model should be gradual, initially addressing fundamental principles, and should operate simultaneously with, and in the same environment as, workforce development and organisational transformation initiatives, to create sustainable improvements.     

The fracture response of blended formulations containing limestone powder: Evaluations using two-parameter fracture model and digital image correlation

The fracture response of mortars in which OPC is partially replaced by limestone or a combination of limestone and fly ash/metakaolin (i.e., for total OPC replacement levels of 20% and 35% by volume) is reported. The blended mortars demonstrate fracture parameters (fracture toughness, K_IC^S and critical crack tip opening displacement, CTOD_c, determined using the two-parameter fracture model, TPFM) that are comparable to or better than those of pure OPC formulations in spite of having slightly lower compressive strengths than the OPC systems. The ternary blends containing limestone and metakaolin at 20% OPC replacement show the best performance: a consequence of the beneficial limestone–alumina synergy that has been previously established. The strain energy release rates also show trends that are in line with the other fracture parameters. The fracture parameters for selected mixtures evaluated through a non-contact digital image correlation technique are found to correspond well to those determined from TPFM. The outcomes highlight that improved ductility can be attained through the judicious use of limestone and synergistic OPC replacement materials.     

Three-dimensional atomic imaging of Y and (B12)13 clusters in YB56 by HREM and crystallographic image processing

The three-dimensional atomic image of YB₅₆ was obtained by inverse Fourier transformation of three-dimensional phases and amplitudes in three high-resolution images along [100], [110] and [111] of YB₅₆ crystals. After crystallographic image processing, the image directly showed the three-dimensional potential map of the crystal, which showed (B₁₂)₁₃ clusters and Y atom positions. The present method would be useful for three-dimensional structure analysis in nanoscale regions.     

密实型低噪声路面动态模量的超声波法研究

配制了传统的沥青混凝土（AC）、碎石沥青玛蹄脂（SMA）、不同橡胶粉掺量的骨架密实型低噪声路面等3类5个配比的沥青路面，采用超声波法测量了各类沥青路面的动态模量。并且分析了橡胶粉掺量对密实型低噪声路面动态模量的影响，初步得出了以橡胶粉含量为3％的密实型路面的减振降噪效果最好的结论。     

Analysis of cement pastes and mortars by a combination of backscatter-based SEM image analysis and calculations based on the Powers model

Formation of microstructure in cement pastes and mortars were quantitatively analyzed by the SEM-BSE image analysis. Effects of water/cement ratio and of the addition of mineral admixtures on the contents of unhydrated cement particles and pores were discussed. The proportions of each phase obtained by the analyses were compared with proportions calculated on the Powers model. It was found from comparisons that the volume fractions of the residual cement and pores obtained by the image analysis did not contradict those estimated from the Powers model. Lower water/cement ratio pastes and those undergoing pozzolanic reaction showed less fine capillary pores. It was also found that large capillary pores still remained in the mixtures at long ages. The gel/space ratio in the Powers and Brownyard equation was calculated from the phase constituents determined by the image analysis. For mortars without mineral admixture, the gel/space ratio by the image analysis could be related to the strength.