Mammalian Exocrine Secretions. XVIII: Chemical Characterization of Interdigital Secretion of Red Hartebeest, Alcelaphus buselaphus caama

Gas chromatography, coupled gas chromatography-mass spectrometry (electron impact mode and chemical ionization with methane as reactant gas), gas chromatography-infrared spectroscopy, and derivatization techniques were used to identity 53 compounds in the interdigital secretion of the red hartebeest, Alcelaphus buselaphus caama. These compounds included alkanes, isoalkanes, alcohols, ketones, carboxylic acids, oxiranes, furanoid linalool oxides, and a large number of branched and unbranched saturated and unsaturated aldehydes. The secretion probably plays a role in demarcation of territories by dominant bulls.     

基于多通道分离整合的多尺度单幅图像去雨算法

由于密度不同的雨对图像造成的遮挡不同,图像去雨一直都是一项极具挑战性的任务。目前,基于深度学习的图像去雨算法已经成为主流。然而,多数深度学习的架构都是通过堆叠卷积层来设计的,执行去雨任务后图像仍存在着大小不一的雨痕,这些方法并不能很好地关注训练中雨图的局部信息和上下文信息。为了解决上述问题,本文设计一种基于多通道分离整合的卷积神经网络用于图像去雨。第一步通过通道分离,再利用卷积层间的层级连接,构成多尺度模块,最终将不同通道的输出进行整合。该模块可以增大感受野,探索特征图之间的空间信息,更好地提取特征。第二步利用渐进网络来反复计算挖掘上下文信息,能够很好关联到全局特征。整体模型易于实施,可以端对端训练。在常用的数据集以及自建的自动驾驶雨天数据集上的大量实验表明,本文方法比现有方法取得了明显的改进。     

Partial correction for turbulent distortions in telescopes

To provide complete compensation for turbulent distortions in the visible range at aperture dimensions typical for modern telescopes (6-10 m), one needs to develop adaptive systems with hundreds of control channels. More simple adaptive systems that provide complete compensation in the infrared range can give an essential advantage in angular resolution in the visible range too. In this case the image brightness characterized by the Strehl ratio remains much less than that in the diffraction-limited case, i.e., the system provides only partial compensation. We present the results of numerical calculations of the partially corrected point-spread function and discuss possible approaches to composing the adaptive system configuration.     

Modeling the Wavelength Dependence of the Index of Refraction of Water in the Range 200 nm to 200 mum

We modeled the index of refraction of water at a temperature of25 degrees C, employing a Lorentz model for wavelengths ranging from 200 nmto 200 mum. We determined model parameters by minimizingdiscrepancies between calculated and experimental data, using an elitegenetic algorithm with adaptive mutations. We found that a Lorentzmodel with six oscillators fits the available data well in the wholerange of interest.     

Multiple circular-harmonic-function correlation filter providing specified response to in-plane rotation

The circular-harmonic-function correlation filter originally proposed by Hsu and Arsenault [Appl. Opt. 21, 4016 (1982)] for in-plane rotation invariance uses only one harmonic, which results in poor discrimination capability of the filter. Various methods to use multiple harmonics were explored previously by different researchers. We present a new method to combine multiple circular harmonics into a single filter that can provide the desired correlation response to in-plane rotation while minimizing the correlation-plane energy. Since multiple harmonics are included, the filter can discriminate well, and since correlation-plane energy is minimized, correlation peaks tend to be sharp. Since the designer can specify the desired in-plane rotation response, a variety of filter behaviors (including complete invariance to input rotations) can be obtained. Underlying theory is discussed, and simulation results are presented.     

Wide-angle stray-light reduction for a spaceborne optical hemispherical imager

We describe a simple visible-light stray-background-reducing baffle, suitable for use on a stabilized interplanetary platform. The design is a corrallike enclosure with five concentric walls. The baffle reduces direct sunlight and reflections from illuminated portions of the spacecraft by a factor of 10(-12), provided that all these lie beyond at least a hemisphere centered on the viewing aperture. With this condition these bright sources do not directly illuminate within the outermost wall of the corral, and diffraction over the wall tops is the dominant mechanism by which light reaches the corral interior. We present design calculations for such a corral, as well as a laboratory measurement confirming the basic design assumption.     

A bayesian approach to deformed pattern matching of iris images

We describe a general probabilistic framework for matching patterns that experience in-plane nonlinear deformations, such as iris patterns. Given a pair of images, we derive a maximum a posteriori probability (MAP) estimate of the parameters of the relative deformation between them. Our estimation process accomplishes two things simultaneously: it normalizes for pattern warping and it returns a distortion-tolerant similarity metric which can be used for matching two nonlinearly deformed image patterns. The prior probability of the deformation parameters is specific to the pattern-type and, therefore, should result in more accurate matching than an arbitrary general distribution. We show that the proposed method is very well suited for handling iris biometrics, applying it to two databases of iris images which contain real instances of warped patterns. We demonstrate a significant improvement in matching accuracy using the proposed deformed Bayesian matching methodology. We also show that the additional computation required to estimate the deformation is relatively inexpensive, making it suitable for real-time applications     

新型城镇化导向下传统乡镇转型发展路径的探讨——以富阳永昌镇总体规划为例

以富阳永昌镇为例,分析了传统乡镇由乡村工业化带动的城镇化方式转变为依托本土资源诱导推动和借助区域协同融合拉动,提出并重点探讨了新型城镇化导向下,传统乡镇转型发展的动力研判、目标导向和空间落实等一系列实现路径。