琼州海峡新海汽车轮渡码头通航水流条件分析

研究采用DELFT3D软件技术建立了工程海区潮流数学模型。首先,采用实测资料对模型进行率定;接着对海域天然工况进行模拟,分析了工程前水域水流特征;最后,对建设方案进行模拟,研究了汽车轮渡进港航道和港区流速分布情况,并对工程引起的粤海铁路轮渡南港进港航道水流条件变化进行了分析,为项目建设提供了科学依据和技术支撑。     

染料木黄酮对大菱鲆生长、消化酶活力和肠道组织结构的影响

以鱼粉为主要蛋白源配制了5种不同剂量的染料木黄酮(0、5、10、20、100mg·kg-1)的实验饲料,来研究其对大菱鲆生长、消化酶活力和肠道组织结构的影响。结果表明:饲料中添加不同剂量的染料木黄酮对大菱鲆幼鱼的存活、终末体重、特定生长率、饲料效率、摄食率以及肥满度、脏体比和肝体比均未产生显著影响(P0.05);饲料中添加染料木黄酮显著降低了鱼体粗蛋白和粗脂肪含量并显著提高了鱼体水分含量(P0.05),但对鱼体灰分含量无显著影响(P0.05);饲料中添加染料木黄酮显著降低了胃蛋白酶、胰蛋白酶和肠淀粉酶的活性(P0.05),但对肠蛋白酶和胃淀粉酶的活性未产生显著影响(P0.05);饲料中染料木黄酮的添加量达100mg/kg时会对鱼的肠道组织结构产生一定的破坏作用,而其他处理组间肠道组织结构没有明显的差异。实验结果表明,饲料中添加高剂量的染料木黄酮对大菱鲆的生长性能和消化吸收会造成一定的负面作用,使用大豆蛋白做蛋白源时,其含有的染料木黄酮的抗营养作用不可忽视。     

浅谈VBA在工作中的应用

笔者根据多年的工作经验,结合具体实例探讨了Excel内置开发工具VBA(Visual Basic for Application)在实际工作中的应用技巧,解决了在数据处理过程中繁杂的操作步骤和大量数据的数学计算,有效杜绝了人工操作带来的错误。     

基于MATLAB图像处理的汽车牌照识别研究

汽车牌照识别是智能交通领域的重要研究课题,整个过程主要分为预处理、车牌定位、字符分割、字符识别4个环节。用MATLAB软件编写代码实现每一个过程,有效地解决恶劣环境下的车牌定位、字符倾斜、字符分割等复杂问题,结果表明MATLAB在彩色汽车牌照的识别中十分有效。     

Morphological and histological changes in the brains of turbot (Scophthalmus maximus) with gonadal development

The brain plays a critical role in controlling reproduction through the hypothalamus-pituitary-gonadal (HPG) axis in vertebrates. Turbot (Scophthalmus maximus) has become an economically important marine fish in Europe and North China. Previous research investigating turbot reproduction has focused on the role of the HPG axis in regulating egg and sperm production. However, the morphology and histology of the organs in the HPG axis have not been studied. In this study, we investigated the morphology and histology of brains in female and male turbot at different stages of gonadal development. The results showed that the brains of both female and male turbot were composed of seven parts that are typical of advanced teleosts: the telencephalon, diencephalon, cerebellum, hypothalamus, pituitary gland, myelencephalon, and olfactory bulbs. The telencephalon was well-developed and contained five distinct lobes, with the contiguous diencephalon at the caudal portion. The torus longitudinales and rostral torus semicircularis of the mesencephalon flattened along the dorsal surface, and the rostral corpus cerebellum was located in the dorsal portion. The actual total brain volume in mature males was significantly greater (p<0.05) than that of females with gonadal development. Notably, the pituitary volume in male turbot significantly increased (p<0.05) from immature to mature stage, but this difference did not occur in females. The data together illustrate a distinct sex difference in the turbot brain during gonadal development, providing insight into their HPG axes.     

红纤维虾形草(Phyllospadix iwatensis)种子形态及内部特征

海草床可以为海洋动物提供产卵、索饵、繁育等场所。目前, 海草床面积急剧下降, 其中我国关于虾形草属(Phyllospadix)海草的研究相对较少, 对于虾形草主要繁育载体种子的描述、显微观察和萌发过程方面存在较多空白。本研究以红纤维虾形草(Phyllospadix iwatensis)为研究对象, 对其生长环境、种子外部特征、内部结构、萌发过程等进行了定性定量描述。结果表明, 虾形草果实种子对于海洋环境有着外部形态与内部结构的适应性, 外部形态特点包括独特的果序和果实形状, 以及翅状结构和内侧鬃毛, 其中果序呈弯虾形, 平均长度3.4cm, 果实呈马掌形, 直径3~4mm, 内部结构特征包括胚乳占比大、果皮种皮解剖结构复杂等, 具有作为海岸带植被修复工具种的优势。本研究补充了目前对虾形草等海洋沉水植物种子的研究资料, 为虾形草海草种质库保护与海草床修复提供了建议和参考。     

Urban accessibility diagnosis from mobile laser scanning data

In this paper we present an approach for automatic analysis of urban accessibility using 3D point clouds. Our approach is based on range images and it consists in two main steps: urban objects segmentation and curbs detection. Both of them are required for accessibility diagnosis and itinerary planning.Our method automatically segments facades and urban objects using two hypotheses: facades are the highest vertical structures in the scene and objects are bumps on the ground on the range image. The segmentation result is used to build an urban obstacle map. After that, the gradient is computed on the ground range image. Curb candidates are selected using height and geodesic features. Then, nearby curbs are reconnected using Bézier curves. Finally, accessibility is defined based on geometrical features and accessibility standards.Our methodology is tested on two MLS databases from Paris (France) and Enschede (The Netherlands). Our experiments show that our method has good detection rates, is fast and presents few false alarms. Our method outperforms other works reported in the literature on the same databases.     

基于分水岭算法的高分遥感图像道路提取优化方法

针对高分辨率遥感图像城市道路提取中存在的问题,在面向对象方法和数学形态学等理论基础上,提出了一种基于改进的分水岭分割算法的道路提取方法.在图像预处理基础上,首先使用改进的分水岭算法分割影像,提取基本的道路信息;然后利用面向对象方法提取道路基元,完善道路信息;最后将道路信息二值化,并采用数学形态学等方法进行优化,去除和修补不完善的道路.结果表明,该方法能有效地提取出城市地区的道路信息,对较复杂的道路环境也有较好的效果.     

Use of geo-spatial information and technologies for analyzing morphological changes in the Greater Visakhapatnam coastal region,east coast of India

The objective of this study was to investigate the land use/land cover, landforms, shoreline and coastal regulation zone (CRZ) changes of Greater Visakhapatnam coastal region using Indian Remote Sensing-IRS P6 (Resourcesat-I) satellite data and collateral information. Prominent changes have been observed during the past 30 years through land use/land cover analyzes which clearly indicate that thecoastal regulatory zones have altered in respect of both natural and anthropogenic activities. Various geomorphic units were identified and confirmed with appropriate field work. Significant changes have been recognized in the shoreline map, which denote that the area of erosional shoreline is larger than the accretional and stable prone shoreline. The availability of high resolution data has helped to prepare large-scale maps for implementation of CRZ measures. The results were promising and suggest that the modern geo-spatial information and technological tools are extremely helpful for conducting coastal morphological studies.     

Pedoiogisk kortlægning og jordbundsbonitering i et geestrandområde ved Tønder

Jakobsen, Bjarne Holm: Pedoiogisk kortlægning og jordbundsbonitering i et geestrandområde ved Tønder. Geografisk Tidsskrift 81: 17–32. København, Juni 1, 1981.

The result is presented of a detailed pedological survey of the geest at the margin of the Tønder Marsh-Area. Maps showing the parents sediments, the pedology and the drainage class have been constructed. Furthermore a soil capability map is shown using the land valuation principles of the Federal Republic of Germany.