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1.
This paper presents a zero‐padding and cross‐correlation technique‐based correlation mapping optical coherence tomography (ZPCC‐cmOCT) to reconstruct microcirculation maps of human skin in vivo, which can remove the background decorrelation noise caused by motion artefacts. In conventional correlation mapping optical coherence tomography method, the correlation degree of static tissue may be lowered by the motion artefacts due to cardiac and respiratory motion, resulting in background decorrelation noise in microcirculation maps. In zero‐padding and cross‐correlation technique‐based correlation mapping optical coherence tomography method, structural images are first obtained by performing Fourier transform on zero‐padded interference fringes, and then cross‐correlation‐based image registration is utilized to align local areas in two adjacent structural images. Finally, correlation mapping optical coherence tomography method is performed to generate microcirculation maps. Both phantom experiments and in vivo experiments were implemented and the results demonstrate that the proposed method is capable of providing microcirculation maps with the background decorrelation noise removed.  相似文献   

2.
A method is described for transmission electron microscopy which allows high resolution mapping of three lectin receptors on the same cell. As a model, receptors for Concanavalin A, soya bean and wheat germ agglutinins have been simultaneously localized on human erythrocytes using lectin-labelled gold markers of different sizes (5, 17 and 26 nm, respectively). Quantitative binding data and examination of stereoscopic micrographs of thin sections of marked erythrocytes indicated that the greatest part of these lectin markers was bound by receptors spatially separated. As gold granules are electron dense and uniform in size, they are well suited for multiple marking of cell surface components. The method is simple and leads to a better understanding of the topography of cell membranes.  相似文献   

3.
含故障齿轮非线性系统的全局性态分析是对齿轮正确故障诊断的状态依据,运用能够反映非线性系统复杂全局性态的简单胞映射方法,把故障齿轮非线性系统所处的状态空间转化为胞空间,对齿轮非线性系统在不同程度磨损故障状态下的动力系统的全局特性进行了分析,通过对比不同程度故障下系统的吸引域及其吸引胞,得到磨损故障齿轮非线性系统全局特性的变化规律,为齿轮非线性系统的故障诊断提供了另一种研究思路和方法。  相似文献   

4.
Aiming at the problem of structure design in reverse-design of mechanism, a structure mapping method based on reverse solving of locus and motion (RSLM) is presented. The mechanism scheme meeting the requirements of geometric and structural features is obtained through RSLM. The element instance subsets related to component are established based on the element type mapping, pair structure type mapping and design knowledge mapping between components and elements layer by layer. The assembly position mapping of elements is established based on the topological structure information of mechanism scheme, and the product modeling of structure mapping is realized. The algorithm program and prototype system of product structure mapping based on RSLM are developed. Application samples show that the method implements the integration of scheme design, assembly design and structure design, and modeling for product structure mapping based on RSLM. The feasibility of assembly is analyzed in scheme design that contributes to reducing the design error, and raising the design efficiency and quality.  相似文献   

5.
基于映射原理和遗传算法提出了一种判别图同构特征的复合算法,该算法通过研究两个图的映射关系并进行编码,结合遗传算法构建同构判别问题的模型。针对同构识别中码元不能重复的特征,提出了交叉算子和变异算子的重新设计对策;引入模拟退火算法确定了从当前解到新解转移的概率,从而避免陷入局部最优;基于数学实验提出了一些模型参数的选择原则以提高算法效率。算例表明,该复合算法可有效地应用于机构图的同构判别,为机构创新设计智能CAD研究提供了一种有效的同构识别方法。  相似文献   

6.
A method of cell surface mapping has been developed on spermatozoa. Concanavalin A binding sites have been simultaneously revelaed both by peroxidase DAB reaction and by iron dextran coupling. The areas are examined in scanning and transmission electron microscopes and submitted to electron probe X-ray microanalysis.  相似文献   

7.
Previous work using focused ion beam (FIB) analysis of osteoblasts on smooth and microrough Ti surfaces showed that the average cell aspect ratio and distance from the surface are greater on the rough surface. In order to better interrogate the relationship between individual cells and their substrate using multiple imaging modalities, we developed a method that tracks the same cell across confocal laser scanning microscopy (CLSM) to correlate surface microroughness with cell morphology and cytoskeleton; scanning electron microscopy (SEM) to provide higher resolution for observation of nanoroughness as well as chemical mapping via energy dispersive X‐ray spectroscopy; and transmission electron microscopy (TEM) for high‐resolution imaging. FIB was used to prepare thin sections of the cell‐material interface for TEM, or for three‐dimensional electron tomography. Cells were cultured on laser‐sintered Ti‐6Al‐4V substrates with polished or etched surfaces. Direct cell to surface attachments were observed across surfaces, though bridging across macroscale surface features occurred on rough substrates. Our results show that surface roughness, cell cytoskeleton and gross morphology can be correlated with the cell‐material cross‐sectional interface at the single cell level across multiple high‐resolution imaging modalities. This work provides a platform method for further investigating mechanisms of the cell‐material interface.  相似文献   

8.
传输型立体测绘卫星利用测绘相机进行摄影测量时,需要确定测绘相机在惯性坐标系中的姿态。确定姿态时,首先由星敏感器测量得到星敏测量坐标系在惯性坐标系中的姿态,然后通过星敏测量坐标系与星敏立方镜的转换矩阵、星敏立方镜与测绘相机立方镜的转换矩阵,得到测绘相机测量坐标系在惯性坐标系中的姿态。文中介绍了各坐标系的定义,根据星敏立方镜与测绘相机立方镜坐标系的关系,利用4台经纬仪测量系统分别建立星敏立方镜和测绘相机立方镜的坐标系以及2坐标系间的转换矩阵,介绍了2个立方镜坐标系的标定方法,多次测量结果表明,最大标定误差为1.011 6",优于2"(1σ),满足立体测绘精度的要求。  相似文献   

9.
Two-dimensional temperature mapping of laser heated diamond anvil cell samples is performed by processing a set of four simultaneous images of the sample, each obtained at a narrow spectral range in the visible to near infrared. The images are correlated spatially, and each set of four points is fitted to the Planck radiation function to determine the temperature and the emissivity of the sample, using the gray body approximation. The method is tested by measuring the melting point of Pt at 1 bar and measuring laser heated Fe at 20 GPa in the diamond anvil cell. The accuracy and precision are shown to compare well to standard spectroradiometry, and the effect of imaging resolution on the measured distribution is evaluated. The principal advantages of the method are (1) the temperature and emissivity of the sample are mapped in two dimensions; (2) chromatic aberrations are practically eliminated by independent focusing of each spectral band; and (3) all of the spectral images are obtained simultaneously, allowing temporal variations to be studied. This method of measuring temperature distributions can be generalized to other hot objects besides laser heated spots.  相似文献   

10.
基于Web的定单配置系统的相关技术和应用方案的研究   总被引:4,自引:1,他引:4  
针对大规模定制生产的特点,提出基于产品特征分离的BOM结构和产品结构单元库。基于客户需求和产品结构单元配置特征之间的映射关系,提出产品配置器来完成对客户配置需求的快速响应,以实现对设计过程的重组,并给出了需求特征匹配算法。对于配置产品的可视化表达,提出了基于VRML和SVG相结合的表达方案。给出了基于Web的定单配置系统的三层应用框架结构。  相似文献   

11.
新型的一步模拟法通用初始域求解方法   总被引:1,自引:0,他引:1  
比较目前在板料成形一步模拟法中常用到的初始域计算方法的特点,针对这些方法的缺点提出采用基于能量理论的空间网格映射法与反向变形法相结合的初始域计算方法.该算法可克服垂直投影法因零投映面积而不能迭代计算的问题,并能解决几何映射法需要寻找对称线、断面线展开法无法解决局部网格畸变的问题.复杂拉延件的实例中,通过对各种结合方案的比较得知:尽管它们获得的最终初始域是一致的,但Desbrun二次能量法及一致参数化法与反向变形法相结合的方案具有较高的稳定性和较好的计算效率,并能解决无法获取通用并高效的一步模拟法初始域求解问题.  相似文献   

12.
基于成像光线空间追踪的摄像机标定方法研究   总被引:2,自引:0,他引:2  
摄像机测量模型和标定方法是视觉测量的关键,直接影响视觉测量系统的测量精度。针对这个问题,借鉴非成像模型的摄像机校准的思想,提出了基于成像光线追踪的摄像机标定方法。分析测量点经摄像机镜头成像的规律,通过空间直线确定摄像机图像坐标与测量空间的映射关系。使用像平面和两个空间平面的映射关系,建立空间直线表达方式,完成基于成像追踪方法的摄像机测量参数标定。通过噪声分析和精度测量实验对基于成像追踪的摄像机标定方法进行精度验证,实验结果表明该方法可以有效抑制标定数据噪声对测量结果的影响,提高摄像机标定精度。  相似文献   

13.
We present a sample preparation method for measuring magnesium in individual whole lymphocytes by electron probe X-ray microanalysis. We use Burkitt's lymphoma cells in culture as the test sample and compare X-ray microanalysis of individual cells with atomic absorption analysis of pooled cell populations. We determine the magnesium peak-to-local continuum X-ray intensity ratio by electron probe X-ray microanalysis and calculate a mean cell magnesium concentration of 39± 19 mmol/kg dry weight from analysis of 100 cells. We determine a mean cell magnesium concentration of 34 ±4 mmol/kg dry weight by atomic absorption analysis of pooled cells in three cell cultures. The mean cell magnesium concentrations determined by the two methods are not significantly different. We find a 10% coefficient of variation for both methods of analysis and a 30% coefficient of variation in magnesium concentration among individual cells by electron probe X-ray microanalysis. We wash cells in ammonium nitrate for microanalysis or in buffered saline glucose for atomic absorption analysis. We find cells washed in either solution have the same cell viability (85%), recovery (75%), cell volume (555 μm3) and cytology. We air dry cells on thin film supports and show by magnesium X-ray mapping that magnesium is within the cells. We conclude that: (a) our microanalysis cell preparation method preserves whole intact lymphocytes; (b) there is no systematic difference in results from the two methods of analysis; (c) electron probe X-ray microanalysis can determine the variation in magnesium concentration among individual cells.  相似文献   

14.
Aiming at the problem of abstract and polytype information modeling in product conceptual design, a method of conceptual modeling based on logical expression and evolvement is presented. Based on the logic expressions of the product conceptual design information, a function/logic/structure mapping model is set up. First, the function semantics is transformed into logical expressions through function/logic mapping. Second, the methods of logical evolvement are utilized to describe the function analysis, function/structure mapping and structure combination. Last, the logical structure scheme is transformed into geometrical sketch through logic/structure mapping. The conceptual design information and modeling process are described uniformly with logical methods in the model, and an effective method for computer aided conceptual design based on the model is implemented.  相似文献   

15.
一种三线阵测绘相机CCD像面的装调方法   总被引:6,自引:0,他引:6  
为了保证三线阵测绘相机装调后相机之间的空间位置关系,保证三线阵测绘相机应用时的测绘精度和图像质量,对三线阵测绘相机CCD像面的装调方法进行研究.首先,根据测绘精度和图像质量的要求,明确了三线阵测绘相机的装调指标.其次,确定了装调方案,对装调要点进行了叙述,为三线阵测绘相机的装调提供了一种装调方法.实际装调检测结果表明,应用该方法可以将相机之间空间位置关系安装到α≤3"、β≤5"、γ≤5".该方法可以满足三线阵测绘相机之间的空间位置关系装调,具有实际应用价值.  相似文献   

16.
针对飞机装配过程中壁板铆接变形预测仿真计算周期长的问题,依据局部-整体映射的思想,提出了基于局部位移场的分层映射方法,建立了映射模型,并将所提模型与三维动态模型的有限元分析结果进行了对比。研究结果表明:所提方法可有效地缩短仿真计算时间及提高模拟实际钻铆过程的可靠性;采用所提方法时的轴向位移相对误差为2.2%;当映射区域为2.5R(R为钉孔半径)时,单钉铆接的计算时间由45.56 min缩短至3.33 min。通过三钉模型验证了所提方法的有效性。  相似文献   

17.
科学计算可视化智能映射技术的研究   总被引:1,自引:0,他引:1  
分析了可视化映射的特点,提出了一种在可视化映射问题进行方案设计时,将神经网络用于类比和联想,在可视化映射方案进行选择与调整时,将专家系统用于逻辑推理的可视化智能映射技术。  相似文献   

18.
一种新的红细胞沉降率测定方法   总被引:1,自引:0,他引:1  
血红细胞沉降率是临床诊断中需测试的一项重要参数 ,传统的魏氏法是一种手工测量方法且测试周期长 ,不适应大批量测试。运用映射函数和回归分析原理 ,提出了一种新的测试方法 ,该方法测试时间是魏氏法的一半、与魏氏法的相关性好。使用该方法构成的测试仪器经临床使用 ,测试稳定 ,效果良好。  相似文献   

19.
An electrochemical method for loading electroactive materials over the TEM grid is reported. The protocol has been demonstrated using polyaniline as an example. The electroactive polymer was directly deposited over the Au TEM grid, used as working electrode in a 3 electrode electrochemical cell. The undisturbed as‐deposited morphologies under the influence of various counter ions and ex situ electrochemical states have been studied and compared. Contrary to behaviour in bulk the individual polyaniline fibre was found thinner at anodic potentials. The movement of counter ions as a function of the electrochemical state of the polymer was studied using STEM‐EDX elemental mapping.  相似文献   

20.
Topological analysis of cells and subcellular structures on the basis of image data, is one of the major trends in modern quantitative biology. However, due to the dynamic nature of cell biology, the optical appearance of different cells or even time-series of the same cell is undergoing substantial variations in shape and texture, which makes a comparison of shapes and distances across different cells a nontrivial task. In the absence of canonical invariances, a natural approach to the normalization of cells consists of spherical mapping, enabling the analysis of targeted regions in terms of canonical spherical coordinates, that is, radial distances and angles. In this work, we present a physically-based approach to spherical mapping, which has been applied for topological analysis of multichannel confocal laser scanning microscopy images of human fibroblast nuclei. Our experimental results demonstrate that spherical mapping of entire nuclear domains can automatically be obtained by inverting affine and elastic transformations, performed on a spherical finite element template mesh.  相似文献   

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