共查询到20条相似文献，搜索用时 718 毫秒
1.
提出了一种基于光场渲染的动态3D目标重构的方法.目前基于图像建模的方法对于复杂场景难以建模,而基于图像渲染的方法因数据量大不利于动态场景的实时渲染.因此采用了模型和图像相结合的方法,从多视点视频图像中重建动态3D模型,采用光场映射算法对重建的3D模型进行光场采样,然后对样本分解压缩.实验结果表明,在保证真实感的同时,减少了数据量,并可实现动态3D目标的重构. 相似文献
2.
登机桥全自动接机中飞机舱门运动模糊图像恢复研究 总被引：1，自引：0，他引：1
在基于计算机视觉的登机桥全自动接机过程中,成像设备采集的图像由于和目标之间存在相对运动,会导致图像模糊,提出了一种登机桥在不同运动模式下的点扩散函数(PSF)的参数估计方法,以及对运动模糊图像恢复的方法。试验表明,本文的方法在登机桥全自动接机过程中表现出了很高的性能。 相似文献
3.
Jeong Ah Kim Hong Nam Kim Sun-Kyoung Im Seok Chung Ji Yoon Kang Nakwon Choi 《Biomicrofluidics》2015,9(2)
We present an engineered three-dimensional (3D) in vitro brain microvasculature system embedded within the bulk of a collagen matrix. To create a hydrogel template for the functional brain microvascular structure, we fabricated an array of microchannels made of collagen I using microneedles and a 3D printed frame. By culturing mouse brain endothelial cells (bEnd.3) on the luminal surface of cylindrical collagen microchannels, we reconstructed an array of brain microvasculature in vitro with circular cross-sections. We characterized the barrier function of our brain microvasculature by measuring transendothelial permeability of 40 kDa fluorescein isothiocyanate-dextran (Stoke''s radius of ∼4.5 nm), based on an analytical model. The transendothelial permeability decreased significantly over 3 weeks of culture. We also present the disruption of the barrier function with a hyperosmotic mannitol as well as a subsequent recovery over 4 days. Our brain microvasculature model in vitro, consisting of system-in-hydrogel combined with the widely emerging 3D printing technique, can serve as a useful tool not only for fundamental studies associated with blood-brain barrier in physiological and pathological settings but also for pharmaceutical applications. 相似文献
4.
5.
6.
Shuang Wang Chen-Yu Wang Pengfei Wang Cong Wang Zhu-An Li Chen Pan Yitong Dai Anyuan Gao Chuan Liu Jian Liu Huafeng Yang Xiaowei Liu Bin Cheng Kunji Chen Zhenlin Wang Kenji Watanabe Takashi Taniguchi Shi-Jun Liang Feng Miao 《国家科学评论(英文版)》2021,8(2)
Compared to human vision, conventional machine vision composed of an image sensor and processor suffers from high latency and large power consumption due to physically separated image sensing and processing. A neuromorphic vision system with brain-inspired visual perception provides a promising solution to the problem. Here we propose and demonstrate a prototype neuromorphic vision system by networking a retinomorphic sensor with a memristive crossbar. We fabricate the retinomorphic sensor by using WSe2/h-BN/Al2O3 van der Waals heterostructures with gate-tunable photoresponses, to closely mimic the human retinal capabilities in simultaneously sensing and processing images. We then network the sensor with a large-scale Pt/Ta/HfO2/Ta one-transistor-one-resistor (1T1R) memristive crossbar, which plays a similar role to the visual cortex in the human brain. The realized neuromorphic vision system allows for fast letter recognition and object tracking, indicating the capabilities of image sensing, processing and recognition in the full analog regime. Our work suggests that such a neuromorphic vision system may open up unprecedented opportunities in future visual perception applications. 相似文献
7.
Sachin Nair Jun Gao Qirong Yao Michael H G Duits Cees Otto Frieder Mugele 《国家科学评论(英文版)》2020,7(3):620
Confocal Raman microscopy is important for characterizing 2D materials, but its low throughput significantly hinders its applications. For metastable materials such as graphene oxide (GO), the low throughput is aggravated by the requirement of extremely low laser dose to avoid sample damage. Here we introduce algorithm-improved confocal Raman microscopy (ai-CRM), which increases the Raman scanning rate by one to two orders of magnitude with respect to state-of-the-art works for a variety of 2D materials. Meanwhile, GO can be imaged at a laser dose that is two to three orders of magnitude lower than previously reported, such that laser-induced variations of the material properties can be avoided. ai-CRM also enables fast and spatially resolved quantitative analysis, and is readily extended to 3D mapping of composite materials. Since ai-CRM is based on general mathematical principles, it is cost-effective, facile to implement and universally applicable to other hyperspectral imaging methods. 相似文献
8.
Content-based image retrieval for medical images is a primary technique for computer-aided diagnosis. While it is a premise for computer-aided diagnosis system to build an efficient medical image database which is paid less attention than that it deserves. In this paper, we provide an efficient approach to develop the archives of large brain CT medical data. Medical images are securely acquired along with relevant diagnosis reports and then cleansed, validated and enhanced. Then some sophisticated image processing algorithms including image normalization and registration are applied to make sure that only corresponding anatomy regions could be compared in image matching. A vector of features is extracted by non-negative tensor factorization and associated with each image, which is essential for the content-based image retrieval. Our experiments prove the efficiency and promising prospect of this database building method for computer-aided diagnosis system. The brain CT image database we built could provide radiologists with a convenient access to retrieve pre-diagnosed, validated and highly relevant examples based on image content and obtain computer-aided diagnosis. 相似文献
9.
Ikram Khan Anil Prabhakar Chloe Delepine Hayley Tsang Vincent Pham Mriganka Sur 《Biomicrofluidics》2021,15(2)
Organoids are biological systems grown in vitro and are observed to self-organize into 3D cellular tissues of specific organs. Brain organoids have emerged as valuable models for the study of human brain development in health and disease. Researchers are now in need of improved culturing and imaging tools to capture the in vitro dynamics of development processes in the brain. Here, we describe the design of a microfluidic chip and bioreactor, to enable in situ tracking and imaging of brain organoids on-chip. The low-cost 3D printed microfluidic bioreactor supports organoid growth and provides an optimal imaging chamber for live-organoid imaging, with drug delivery support. This fully isolated design of a live-cell imaging and culturing platform enables long-term live-imaging of the intact live brain organoids as it grows. We can thus analyze their self-organization in a controlled environment with high temporal and spatial resolution. 相似文献
10.
国家重点实验室体系在我国科技创新中发挥重要作用,如何释放其最大效能成为这一领域的研究焦点。以我国中文论文数据库为样本,借助知识图谱技术,结合Citespace可视化软件,通过定量化、可视化已有研究文献的研究热点、研究前沿、研究领域及代表性研究成果,绘制了我国国家重点实验室体系研究现状的系列知识图谱。在此基础上,给出了我国国家重点实验室体系研究急需解决的两个关键性问题。即各类国家重点实验室之间的协同创新问题、国家重点实验室体系研究主题的进一步聚焦及代表性成果的显示度问题。这为深化我国国家重点实验室体系研究奠定了理论基础,同时也为提升我国国家重点实验室体系的创新能力指明了方向。 相似文献
11.
根据多基线合成孔径雷达(SAR)三维成像的信号模型,得到了利用高度向观测数据实现目标三维成像的矩阵方程,并引入QR分解算法求解矩阵方程,形成了多基线SAR三维成像的QR分解算法.使用该算法对多基线SAR仿真数据进行了三维成像实验. 相似文献
12.
对大脑的认知是人类认识自然和自身的终极挑战,脑科学研究的核心是理解脑功能的结构及物质基础。中科院在2012年启动了战略性先导科技专项(B类)"脑功能联结图谱计划"(Mapping Brain Functional Connections;简称:脑联接图谱;MBFC,2012—2020),目标是对特定脑功能的神经联结通路和网络结构的解析及模拟。专项代表了脑科学研究的战略制高点,对揭示脑的工作原理、推动智能科学技术进步、增进人类身心健康等方面都具有十分重要的意义。专项设立以来,在感知觉神经环路发育和功能、视觉与本能恐惧行为的神经环路机制、情绪的神经环路编码机制、成瘾和抑郁症等脑疾病机理、意识的神经基础、基因编译技术及脑疾病的非人灵长类模型、神经元分类和功能分析技术及其应用、神经环路双色钙成像方法、神经环路结构与功能研究工具开发、深度神经网络芯片研制,以及资源库与平台建设等方面取得了一系列重要的科学发现和技术研发进展。我们将进一步按照专项十年规划,开展脑认知科学、类脑人工智能技术、脑疾病早期诊断及干预3个前沿领域的科学研究,以及相关新技术研发和脑科技资源库建设,发挥中科院在脑与认知基础研究和技术研发等领域的引领作用。 相似文献
13.
14.
Yogesh M. Patel Sanidhya Jain Abhishek Kumar Singh Kedar Khare Sarita Ahlawat Supreet Singh Bahga 《Biomicrofluidics》2020,14(6)
We present design, characterization, and testing of an inexpensive, sheath-flow based microfluidic device for three-dimensional (3D) hydrodynamic focusing of cells in imaging flow cytometry. In contrast to other 3D sheathing devices, our device hydrodynamically focuses the cells in a single-file near the bottom wall of the microchannel that allows imaging cells with high magnification and low working distance objectives, without the need for small device dimensions. The relatively large dimensions of the microchannels enable easy fabrication using less-precise fabrication techniques, and the simplicity of the device design avoids the need for tedious alignment of various layers. We have characterized the performance of the device with 3D numerical simulations and validated these simulations with experiments of hydrodynamic focusing of a fluorescently dyed sample fluid. The simulations show that the width and the height of the 3D focused sample stream can be controlled independently by varying the heights of main and side channels of the device, and the flow rates of sample and sheath fluids. Based on simulations, we also provide useful guidelines for choosing the device dimensions and flow rates for focusing cells of a particular size. Thereafter, we demonstrate the applicability of our device for imaging a large number of RBCs using brightfield microscopy. We also discuss the choice of the region of interest and camera frame rate so as to image each cell individually in our device. The design of our microfluidic device makes it equally applicable for imaging cells of different sizes using various other imaging techniques such as phase-contrast and fluorescence microscopy. 相似文献
15.
Kang Kug Lee Toru Matsu-ura Andrew E. Rosselot Taylor R. Broda James M. Wells Christian I. Hong 《Biomicrofluidics》2021,15(1)
Perfused three-dimensional (3D) cultures enable long-term in situ growth and monitoring of 3D organoids making them well-suited for investigating organoid development, growth, and function. One of the limitations of this long-term on-chip perfused 3D culture is unintended and disruptive air bubbles. To overcome this obstacle, we invented an imaging platform that integrates an innovative microfluidic bubble pocket for long-term perfused 3D culture of gastrointestinal (GI) organoids. We successfully applied 3D printing technology to create polymer molds that cast polydimethylsiloxane (PDMS) culture chambers in addition to bubble pockets. Our developed platform traps unintended, or induced, air bubbles in an integrated PDMS pocket chamber, where the bubbles diffuse out across the gas permeable PDMS or an outlet tube. We demonstrated that our robust platform integrated with the novel bubble pocket effectively circumvents the development of bubbles into human and mouse GI organoid cultures during long-term perfused time-course imaging. Our platform with the innovative integrated bubble pocket is ideally suited for studies requiring long-term perfusion monitoring of organ growth and morphogenesis as well as function. 相似文献
16.
全景图像技术及其应用 总被引：2，自引：0，他引：2
全景图像技术是一种通过微透镜阵列来记录和显示全真的三维场景的三维图像技术。这种技术的记录过程不需要采用相干光源,同时对观看者也不要求佩戴特殊眼镜。这些特点使这一技术有着十分广泛的应用前景。本文介绍了全景图像系统及它在三维电视、立体印刷、深度测量方面的应用。 相似文献
17.
2012年1月9日发射的我国首颗民用立体测图卫星“资源三号”是我国自主设计、研制和处理的精度最高的卫星。该卫星充分继承了我国资源卫星系列的平台技术,装载前后下视3台全色相机(下视相机分辨率2.1米,前后视相机分辨率3.5米)、1台多光谱相机(分辨率5.8米)、3台星敏感器和2台双频GPS接收机,实现对地三维摄影和多光谱探测,并获取相机成像时刻的高精度轨道与姿态测量数据。地面处理系统利用定期在轨几何检校成果,研究构建了“资源三号”测绘卫星高精度严密成像几何模型和有理函数模型。建立了满足测绘以及相关行业需求、与国内外成熟先进商业卫星接轨的“资源三号”影像产品体系。生产的“资源三号”影像产品无控制点平面精度达到10米,高程精度达到6米,带控制点平面精度达到3—4米,高程精度达到2—3米,处于国际同类领先水平,全面满足1∶5万和1∶2.5万比例尺的立体测图(平原、丘陵、山地和高山区)的精度要求,并可开拓研究其在1∶1万比例尺困难区测图应用的可行性。目前,“资源三号”测绘卫星在轨运行正常,卫星测绘应用成果丰硕,数据已开始全面应用于我国1∶5万基础地理信息产品生产以及更大比例尺地图的修测更新和地理国情监测,正积极服务于国土、规划、林业、农业、减灾等行业,并参与国际交流和合作。 相似文献
18.
19.