Bayesian network based general correspondence retrieval method for depth sensing with single-shot structured light

This study reinvestigated one of the most fundamental problems in structure light depth sensing field: correspondence retrieval of features between patterns and images. We formulate the global optimum correspondence retrieval by maximizing a conditional probability of correspondence given observed features, which is depicted by a Bayesian network. Different from traditional “code-only” based correspondence retrieval methods, the proposed Bayesian network based method exploits the positional correlations of correspondences of neighboring features, namely, the correspondences of poorly detected features are estimated with the aid of the correspondences of well detected features. The method performs especially well on challenging scenes with rich depth variations, abrupt depth changes, edges, etc. Experiments show that the proposed method increase the correspondence accuracy by about 40% on challenging scenes, compared with traditional “code-only” based correspondence retrieval methods.     

Film and television industry cloud exhibition design based on 3D imaging and virtual reality

The three-dimensional virtual scene can provide users with a visual three-dimensional virtual environment, with various multimedia channels such as sound, video, force feedback equipment, etc., to bring users a completely immersive interactive experience. This paper introduces 3D imaging and virtual reality technology in the film and television industry cloud exhibition, and develops a virtual display platform. First of all, this paper divides the registration into two processes: camera calibration and joint calibration of the camera and laser scanner based on the calibration results. Camera calibration can determine the plane model of the calibration board in the camera coordinate system, and the joint calibration uses the RANSAC algorithm to extract the point cloud of the plane model of the calibration board, and then optimizes the distance between the points in the plane model point cloud and the corresponding plane in the camera coordinate system Find the optimal transformation between the two sets of data, and then calculate the registration relationship between the point cloud and the image. Secondly, this article conducts a demand analysis of the film and television industry cloud exhibition platform based on virtual reality technology, including the business goals set by the platform, platform system analysis, overall design, and system operating environment and configuration requirements. This model provides a feasible solution for the visual interaction of the cloud exhibition design of the film and television industry.     

ASRNet: Adversarial Segmentation and Registration Networks for Multispectral Fundus Images

Multispectral imaging (MSI) technique is often used to capture images of the fundus by illuminating it with different wavelengths of light. However, these images are taken at different points in time such that eyeball movements can cause misalignment between consecutive images. The multispectral image sequence reveals important information in the form of retinal and choroidal blood vessel maps, which can help ophthalmologists to analyze the morphology of these blood vessels in detail. This in turn can lead to a high diagnostic accuracy of several diseases. In this paper, we propose a novel semi-supervised end-to-end deep learning framework called “Adversarial Segmentation and Registration Nets” (ASRNet) for the simultaneous estimation of the blood vessel segmentation and the registration of multispectral images via an adversarial learning process. ASRNet consists of two subnetworks: (i) A segmentation module S that fulfills the blood vessel segmentation task, and (ii) A registration module R that estimates the spatial correspondence of an image pair. Based on the segmention-driven registration network, we train the segmentation network using a semi-supervised adversarial learning strategy. Our experimental results show that the proposed ASRNet can achieve state-of-the-art accuracy in segmentation and registration tasks performed with real MSI datasets.     

放电故障紫外检测系统及其状态识别方法

紫外成像检测技术是一种检测高压设备故障的新方法;在此技术上研究设计了一种放电故障紫外检测系统,该系统能对实时采集的紫外图像进行相关的技术处理,同时可对故障点进行准确定位;根据数据建立了设备状态模型并提出一种基于人工神经网络的状态识别方法,应用MATLAB工具进行神经网络的设计和模拟,仿真结果达到预期效果;该系统可以准确地诊断设备的故障和运行状况,有较好运用前景和理论意义。     

红外图像处理在墙体空鼓检测上的应用研究

提出了一种基于红外图像的建筑物墙体空鼓检测方法,不但可以远距离、无损地对建筑物空鼓等缺陷进行定性检测,还能对建筑物热工缺陷进行定量分析;采用一种红外图像处理方法来消除墙体温度分布中梯度干扰的影响;通过自适应地调整参数对红外图像进行图像增强处理,有效地排除了环境干扰;通过基于空鼓缺陷边缘轮廓的连通域计算,可直接得到空鼓面积的大小数据;建筑物缺陷现场检测实验结果表明,提出的检测方法既能快速定位出建筑物空鼓等缺陷位置又能以78.3%的精度检测出空鼓面积大小,具有较高的工程应用性。     

成像卫星星地联合成像调度

成像卫星星地联合调度问题,涉及调度对象众多,约束条件复杂,需要考虑任务的观测、回传2个过程,是一个具有两层时间窗口约束的双层优化问题,统一建模困难。根据问题的特点,采用基于阶段优化的方式,降低了问题的复杂性。把问题分为观测调度阶段和数据回传调度阶段,分别给出了优化目标和约束条件,建立了基于阶段优化的成像卫星星地联合调度模型,实现了从任务观测到数据回传的全过程调度。仿真实例表明,该方法能够有效解决多星多站的协同任务调度问题。     

Photothermal radiometric detection and imaging of surface cracks

This paper discusses surface crack detection by photothermal radiometric imaging (PRI). In PRI, also called dynamic infrared scanning, a surface is scanned with a spot of heat. Imperfections are detected by radiometrically sensing changes in the surface temperature of a small area in the vicinity of this spot. In the work described, cracks narrower than 25 µm (0.001 in.) in a lightly rusted steel surface have been detected. Indiscrete scanning an amplitude modulated heating beam is moved in steps, remaining at each location long enough to measure amplitude and phase of the AC temperature. Incontinuous scanning a constant intensity heating beam is moved continuously while the temperature deviations are measured. This paper presents methods of calculating amplitude and phase of surface temperature for discrete scanning and instantaneous temperature for continuous scanning across a surface crack. For a steel surface scanned by a watt-level laser beam, predicted surface temperature deviations when crossing the crack are several degrees Celsius, with expected radiometrically detected power several orders of magnitude above the detector noise. In experiments performed, both techniques easily detected narrow cracks in a smooth, clean surface. Discolorations and pits, on the other hand, generate a disturbing type of surface noise. This noise was minimized by differential detection. Based on results obtained, continuously scanned PRI with a fan-type heating beam and array detection could become a viable way of mapping surface cracks at practical scanning speeds.     

Sex-Related Differences in Regional Blood–Brain Barrier Integrity in Non-Demented Elderly Subjects

The role of the blood–brain barrier (BBB) breakdown has been recognized as being important in Alzheimer’s disease pathogenesis. We aimed to evaluate whether regional BBB integrity differed according to sex and whether differences in BBB integrity changed as a consequence of aging or cognitive decline, using dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI). In total, 75 participants with normal cognition (NC) or mild cognitive impairment (MCI) underwent cognitive assessments and MRI examination including DCE-MRI. Regional K_trans was calculated in cortical regions and the Patlak permeability model was used to calculate BBB permeability (K_trans, min⁻¹). Females had a lower median K_trans in the cingulate and occipital cortices. In the “older old” group, sex differences in K_trans were only observed in the occipital cortex. In the MCI group, sex differences in K_trans were only observed in the occipital cortex. Age was the only predictor of cognitive assessment scores in the male MCI group; however, educational years and K_trans in the occipital cortex could predict cognitive scores in the female MCI group. Our study revealed that females may have better BBB integrity in cingulate and occipital cortices. We also found that sex-related differences in BBB integrity are attenuated with aging or cognitive decline.     

Novel (Phenothiazinyl)Vinyl-Pyridinium Dyes and Their Potential Applications as Cellular Staining Agents

We report here the synthesis and structural characterization of novel cationic (phenothiazinyl)vinyl-pyridinium (PVP) dyes, together with optical (absorption/emission) properties and their potential applicability as fluorescent labels. Convective heating, ultrasound irradiation and mechanochemical synthesis were considered as alternative synthetic methodologies proficient for overcoming drawbacks such as long reaction time, nonsatisfactory yields or solvent requirements in the synthesis of novel dye (E)-1-(3-chloropropyl)-4-(2-(10-methyl-10H-phenothiazin-3-yl)vinyl)pyridin-1-ium bromide 3d and its N-alkyl-2-methylpyridinium precursor 1c. The trans geometry of the newly synthesized (E)-4-(2-(7-bromo-10-ethyl-10H-phenothiazin-3-yl)vinyl)-1-methylpyridin-1-ium iodide 3b and (E)-1-methyl-4-(2-(10-methyl-10H-phenothiazin-3-yl)vinyl)pyridin-1-ium tetrafluoroborate 3a′ was confirmed by single crystal X-ray diffraction. A negative solvatochromism of the dyes in polar solvents was highlighted by UV-Vis spectroscopy and explanatory insights were supported by molecular modeling which suggested a better stabilization of the lowest unoccupied molecular orbitals (LUMO). The photostability of the dye 3b was investigated by irradiation at 365 nm in different solvents, while the steady-state and time-resolved fluorescence properties of dye 3b and 3a′ in solid state were evaluated under one-photon excitation at 485 nm. The in vitro cytotoxicity of the new PVP dyes on B16-F10 melanoma cells was evaluated by WST-1 assay, while their intracellular localization was assessed by epi-fluorescence conventional microscopy imaging as well as one- and two-photon excited confocal fluorescence lifetime imaging microscopy (FLIM). PVP dyes displayed low cytotoxicity, good internalization inside melanoma cells and intense fluorescence emission inside the B16-F10 murine melanoma cells, making them suitable staining agents for imaging applications.     

Design of the broadband microstrip array antenna for blast furnace surface monitoring

Aiming at the requirements of high-resolution imaging and high integration of the blast furnace radar,this paper presents a method for designing a wideband microstrip array antenna,which broadens the antenna bandwidth through the design of parasitic patches and air layers.By combining multi-input multi-output (MIMO) radar and synthetic aperture radar (SAR) imaging principles,a linear MIMO array is designed,and a near-field simulation imaging experiment is performed on the simulated feed line through the wave number domain imaging algorithm.Simulation results show that the gain of the main lobe of the antenna can reach 14.05 dBi,the reflection coefficient is less than -10 dB,the absolute bandwidth is 5.25 GHz,the operating frequency is 20.67~25.92 GHz,and the range resolution is increased to 3 cm compared with the existing blast furnace radar.The average error of the azimuth direction of the simulated material line imaging is 0.008 m,and the range direction is 0.0011 m.Compared with the traditional microstrip array antenna,this antenna effectively widens the bandwidth,and the range resolution is higher than that of the traditional blast furnace radar.It can accurately obtain the shape information on the simulated material line,and has an engineering application value for blast furnace surface monitoring.