特种监测网解算中IGS站选取的探讨

利用GAMIT/GLOBK软件处理2011年特种监测网的观测数据,将IGS站的选取分10种方案进行试验,计算结果从基线长度变化、测站坐标、NRMS、基线重复率等方面进行了比较。得出利用GAMIT/GLOBK软件处理该特种监测网时的几点建议:建议选取IGS站为GPS网提供参考框架;IGS站选取的数量不一定最多,但空间上应尽量均匀分布;选取7个IGS站时得到较高精度的结果。在日后处理此类型的特种监测网时对IGS站选取具有一定的参考价值。     

动态环境下矢量化路径规划算法

对全方位机器人在完全未知动态环境下实时路径规划和针对移动障碍物的避障问题进行研究。提出矢量化路径描述方法,并将其与Bug算法思想相结合来解决机器人的路径规划问题。机器人的初始路径由其初始位置和目标位置生成,其运动过程是:首先沿初始路径行进,以规定间隔扫描当前环境,判断是否有障碍物阻挡当前路径,并检测障碍物的位置、移动方向和速度等信息;然后根据障碍物信息和机器人安全距离计算路径中间点,并插入中间点更新路径以实现避障。本文的机器人路径规划结果是以矢量形式进行描述及保存的,降低了对路径存储空间的需求,且按规划结果行进时只需要考虑直线移动距离和转动方向,简化了全方位机器人的控制。仿真结果说明本文方法的可行性及有效性。     

Lopingian mixed floras from Linxi Formation in Soron area,Inner Mongolia

A lot of well-preserved plants from the Linxi Formation are collected in the Soron area,Inner Mongolia,consisting of 34 species of 16 genera. They are Late Permian in age. The flora is characterized by a lot of Angaran plants,such as Paracalamites,Comia,Rhachiphyllum,Iniopteris,Rufloria,etc. Some Cathaysian elements,such as Lobatannularia lingulata,L. multifolia,Fascipteris Cathaysiantus,F. densata,Taeniopteris szei,Cladophlebis liulinensis and C. permica,are also mixed within the present flora. This indicates that the Soron of Inner Mongolia was located in the sector between the Angaran and Cathysian floristic provinces in Lopingian. It is beneficial for depicting the location and the evolution of the Solenker--Xar Moron suture zone in the phytogeographic view. The transmigration of tropical and subtropical Cathaysian plants to the north indicates that the Paleoasian Ocean was closed during the late Permian along the suture zone.     

基于模糊小波网络的伺服系统参数辨识研究

伺服系统大多是非线性系统,难以对其建立准确的控制模型,其位置、和速度检测信号易受干扰,而小波网络具有多分辨率特性和任意逼近能力。利用其非线性映射能力对系统的输入输出关系进行模拟,将小波网络和模糊规则结合对系统的位置和速度进行辨识,动态调整网络的权值W和模糊规则,将非线性映射的问题转化为求解系统最优解,从而产生一种新的系统辨识方法,并以永磁伺服系统为例,设计了辨识的结构模型和策略,实验表明该算法可以达到较高的系统控制要求。     

基于Android的电力规划信息系统设计与实现

智能移动终端的飞速发展为电力规划信息在移动平台的展示提供了新的机遇。本文针对离线式移动GIS的特点和优势,结合电力信息系统移动客户端的建设情况,从移动GIS的架构、应用模式、数据组织方案、移动GIS关键技术及实现等方面进行了探讨建立一个基于Android的电力规划信息系统。     

基于潜标测量的海洋环境噪声谱特性分析

利用海洋环境噪声测量潜标系统对南海典型海域开展了为期3个月的海洋环境噪声测量,16通道海洋环境噪声测量系统每小时测量两分钟噪声信号。数据处理结果表明,800~5 000Hz范围内,噪声谱与风速相关性最好,且风速越大相关性越好,噪声谱与风速的相关性好于与浪高的相关性。风关噪声谱级在海水中部基本不随接收深度发生变化,但由于测量水听器阵长度未能覆盖整个水深,因此未给出海面和海底处谱级变化规律。在400Hz以上的高频段整个风速范围内噪声谱级都随风速发生变化,且噪声谱级与对数风速具有很好的线性关系。     

褐藻纲海带目Laminaria属和Saccharina属基于三个分子标记的系统发育分析

In the past two decades, many studies have focused on the classification within genus Laminaria, ultimately trying to divide it into two subgroups or genera: Laminaria and Saccharina. A significant debate still surrounds the question of its division, as the conflicting phylogenetic hypotheses that have resulted from the classification studies are based on different taxon sampling, molecular markers, or analysis methods. It is aimed at elucidate the molecular phylogeny within Laminaria and Saccharina. The nine species of Laminariales are sampled from northern Asia and Europe, and 23 new sequences in the nuclear, plastid, and mitochondrial genomes are determined to identify their taxonomic status. The phylogenetic analyses of 71 species are performed, including representatives from six of the seven families of the order Laminariales, based on three separate data sets. An evidence is provided to strongly support a clear split that maintains the two recognized genera, Laminaria and Saccharina, with Laminaria appearing to be the ancestor group. Further, analyses indicate that all taxa in Saccharina and Laminaria did not form a monophyletic lineage, instead Laminariaceae and Lessoniaceae grouped together interlacedly, and Costariaceae appeared as the sister taxon of the Lessoniaceae–Laminariaceae clade. In the phylogenetic analysis, mitochondrial c oxidase I(COI) sequences appeared to be the most credible molecular marker which was more befitting than nuclear encoded internal transcribed spacer(ITS) and plastid encoded rbcL for establishment of Laminariales systematics. It is the most comprehensive phylogeny of the order Laminariales, and contributes to an enhanced understanding and estimation of the phylogenetic relationships for the economically important seaweeds, Laminaria and Saccharina.     

Ecological indicators showing the succession of macrofauna communities in Sonneratia apetala artificial mangrove wetlands on Qi’ao Island at Zhuhai, South China

The Sonneratia apetala artificial mangroves in the intertidal zone of Da Wei Bay at Qi’ao Island of Zhu-hai, South China were chosen as the macrofauna succession plots while bare tidal flats of the same size were established as control plots in surrounding interference-free areas. Conventional change indicators of community structure, such as biomass and biodiversity, and indicators, such as exergy and specific exergy, which reflect the information change of overall communities, were used to analyze the succession of macro-fauna communities inS. apetala artificial mangroves. The similarities and differences in variation tendency of the different ecological indicators and their reflected ecological principles were compared. The results showed that from D-1 to D-1275 after plantingS. apetala, the biomass of the macrofauna communities first increased, which was then followed by an increase in the network relationship between the macrofauna communities （analysis of the Pielou evenness index and Shannon-Wiener diversity index）. The system in-formation （specific exergy） increased the slowest. Between D-1460 and D-2370 after plantingS. apetala, there was a decrease in biomass, network structure, and system information in the succession plots. After the decrease in the system information （the specific exergy）, there was a decline in the network relationships （Pielou evenness index and Shannon-Wiener diversity index）. Biomass was the last indicator to decrease. The similarities and differences among the different ecological indicators varied during the succession pro-cess, which reflected the relativity and differences among the indicators. This study suggested that, although the species diversity index can be an effective indicator of two types of changes （network structure and system information）, it was quite clear that species diversity measurement was not suitable for expressing the changes in biomass during the succession process. While exergy and specific exergy can provide useful information     

深海会聚区波导不变量特征研究及应用

为了解决深海会聚区目标及其运动态势难以判断的问题,在研究会聚区形成条件和其声场传播规律以及波导不变量理论的基础上,对典型深海环境不同位置的声强距离-频率分布图中的干涉条纹特征进行理论分析和仿真验证。结果表明,深海会聚区存在与其他区域不同的干涉条纹特征,其对应的波导不变量?值为负。本文提出了利用会聚区特有的干涉条纹特征,对会聚区目标及其运动态势进行初步判断的方法,仿真结果和试验数据表明,判断方法具有可行性和有效性。     

中国区域滨海湿地固碳能力研究现状与提升

对我国滨海湿地的固碳能力进行了评估,同时,对其固碳能力的遥感监测和评估方法进行了总结和分析,最后提出了滨海湿地固碳能力的提升技术。全球看来,我国滨海湿地的固碳能力总体上不高。国内看来,在北方泥炭地和植被覆盖率高,生长茂盛的区域,尤其是有红树林生长的区域固碳能力相对较高。滨海湿地主要分布在潮间带,人为监测困难,卫星遥感的出现为滨海湿地的监测带来很大方便,遥感监测已成为评估湿地固碳能力的一种高时效方法。滨海湿地固碳蕴藏着巨大潜力,提升滨海湿地的固碳能力可以大大降低全球CO2含量,对于改善全球温室效应有不可替代的作用。