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81.
In this paper we study the existence and the stability of bounded solutions of the following non-linear system of parabolic equations with homogeneous Dirichlet boundary conditions:
82.
根据某探测设备可见光通道光学系统的特点和技术指标要求,详细介绍长焦距大口径连续变焦光学系统结构形式选择、初始结构参数计算及像差平衡的方法,给出运用该方法设计的采用正组机械补偿形式的长焦距大口径连续变焦光学系统的设计结果。对连续变焦光学系统进行了像质检测、实景成像及环境试验考核,其结果表明:该光学系统能满足某探测设备的性能要求。 相似文献
83.
内腔自适应光学系统校正激光器畸变 总被引:3,自引:1,他引:3
固体激光器中,增益介质由于热沉积产生的热畸变严重影响了激光器的稳定性、输出功率和光束质量。研究了一种内腔自适应光学系统校正激光器腔内畸变的方法,利用微机电变形反射镜作为固体激光器的内腔全反射镜,通过控制变形镜的面型改善激光器输出光束的模式及功率。从腔外引入的一束信标光通过激光器内腔后反射出腔外,用波前探测器可测得激光器工作时腔内畸变对此信标光的影响,并通过搭建的自适应光学系统平台可闭环校正此畸变。实验结果表明,闭环校正后,激光器的输出功率提高了近3倍,且激光光束质量得到了明显的改善。 相似文献
84.
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86.
For efficient progress, model properties and measurement needs can adapt to oceanic events and interactions as they occur. The combination of models and data via data assimilation can also be adaptive. These adaptive concepts are discussed and exemplified within the context of comprehensive real-time ocean observing and prediction systems. Novel adaptive modeling approaches based on simplified maximum likelihood principles are developed and applied to physical and physical–biogeochemical dynamics. In the regional examples shown, they allow the joint calibration of parameter values and model structures. Adaptable components of the Error Subspace Statistical Estimation (ESSE) system are reviewed and illustrated. Results indicate that error estimates, ensemble sizes, error subspace ranks, covariance tapering parameters and stochastic error models can be calibrated by such quantitative adaptation. New adaptive sampling approaches and schemes are outlined. Illustrations suggest that these adaptive schemes can be used in real time with the potential for most efficient sampling. 相似文献
87.
In the present work, we have analyzed the use of elliptical beam shaping along with low numerical aperture focusing optics in order to produce circular cross-section waveguides in different materials at large processing depths by direct femtosecond laser writing (100 fs, 800 nm, 1 kHz). A variable slit located before the focusing optics allows to generate a nearly elliptical beam shape and also to reduce the effective numerical aperture of the beam along the shat axis of the ellipse. The focusing optics allows to focus the beam deep inside the sample, which is translated at a constant speed transversely to the writing beam direction. The influence of several experimental parameters (energy per pulse, slit width, processing depth) on the properties of the produced waveguides has been analyzed. The influence of the intrinsic properties of the material (refractive index, composition) has been analyzed by comparing results obtained in fused silica and Er:Yb co-doped phosphate glass. The results obtained show that this approach leads to the successful production of deep subsurface (up to 7 mm) waveguides with circular cross-sections. Preliminary results using chirped pulses in the phosphate glass suggest that temporal pulse shaping can be used as an additional parameter to optimize the guided mode symmetry. 相似文献
88.
Scanning deflectometric profilers based on an f–gθ system are typical optical tools used to measure mirror profiles at many synchrotron facilities. Unlike these profilers, which are based on a pencil beam, here a secondary light source and a pinhole are used to construct a system that automatically selects a beam that will always pass through the pinhole and propagate along the normal direction of the measured area on the surface under test. By measuring the angle variation of the selected beam, slope variations of the surface under test can be measured. Systematic errors introduced by manufacturing defects or aberrations of an optical element, which greatly degrade the performance of traditional profilers, could be minimized by using the developed method. Simulation values of the proposed method and a conventional method are compared. 相似文献
89.
Zhi Zeng Marina Hincapie Brian B. Haab Samir Hanash Sharon J. Pitteri Steven Kluck Jason M. Hogan Jacob Kennedy William S. Hancock 《Journal of chromatography. A》2010,1217(19):3307-3315
Protein glycosylation represents one of the major post-translational modifications and can have significant effects on protein function. Moreover, changes in the carbohydrate structure are increasingly being recognized as an important modification associated with cancer etiology. In this report, we describe the development of a proteomics approach to identify breast cancer related changes in either concentration and/or the carbohydrate structures of glycoprotein(s) present in blood samples. Diseased and healthy serum samples were processed by an optimized sample preparation protocol using multiple lectin affinity chromatography (M-LAC) that partitions serum proteins based on glycan characteristics. Subsequently, three separate procedures, 1D SDS-PAGE, isoelectric focusing and an antibody microarray, were applied to identify potential candidate markers for future study. The combination of these three platforms is illustrated in this report with the analysis of control and cancer glycoproteomic fractions. Firstly, a molecular weight based separation of glycoproteins by 1D SDS-PAGE was performed, followed by protein, glycoprotein staining, lectin blotting and LC–MS analysis. To refine or confirm the list of interesting glycoproteins, isoelectric focusing (targeting sialic acid changes) and an antibody microarray (used to detect neutral glycan shifts) were selected as the orthogonal methods. As a result, several glycoproteins including alpha-1B-glycoprotein, complement C3, alpha-1-antitrypsin and transferrin were identified as potential candidates for further study. 相似文献
90.
O Introduction
We consider the orbital instability of standing waves for the Klein-Gordon-Zakharov system with different propagation speeds in three space dimensions 相似文献