改进NS2对局域网分布式系统在线仿真的实现

目前大多数仿真系统采用流量发生器等模拟l离散事件的发生,为了充分模拟网络环境中分布式系统各子系统的并发运行和彼此之间依据算法的实时交互,设有虚拟局域网VLAN的IEEE802.1Q协议。提出一种改进NS2模拟局域网分布式系统实际运行的在线仿真的集成方法,将各分布式应用对象移植为NS2的C++扩展对象,执行实际算法,构造一个模拟中心调度对象,管理各分布式对象的并发运行、转发各分布式对象之间的消息交给NS2以模拟其网络延迟,与领域仿真软件交换数据等。对NS2中共享式以太网协议模块改造,添加VLAN802.1Q协议模块,分别实现对交换式局域网和多播报文的模拟。变电站自动化系统的通信网络仿真实验结果,验证了在线仿真方法是有效的、所扩展的NS2模块是正确的。     

Study on Recognition Method of Similar Weather Scenes in Terminal Area

Weather is a key factor affecting the control of air traffic. Accurate recognition and classification of similar weather scenes in the terminal area is helpful for rapid decision-making in air traffic flow management. Current researches mostly use traditional machine learning methods to extract features of weather scenes, and clustering algorithms to divide similar scenes. Inspired by the excellent performance of deep learning in image recognition, this paper proposes a terminal area similar weather scene classification method based on improved deep convolution embedded clustering (IDCEC), which uses the combination of the encoding layer and the decoding layer to reduce the dimensionality of the weather image, retaining useful information to the greatest extent, and then uses the combination of the pre-trained encoding layer and the clustering layer to train the clustering model of the similar scenes in the terminal area. Finally, terminal area of Guangzhou Airport is selected as the research object, the method proposed in this article is used to classify historical weather data in similar scenes, and the performance is compared with other state-of-the-art methods. The experimental results show that the proposed IDCEC method can identify similar scenes more accurately based on the spatial distribution characteristics and severity of weather; at the same time, compared with the actual flight volume in the Guangzhou terminal area, IDCEC's recognition results of similar weather scenes are consistent with the recognition of experts in the field.     

地铁站场景下的可行驶区域检测

在室内环境下的机器人视觉导航任务中,可行驶区域检测是不可或缺的一部分,这是保证自动驾驶任务实现的基础.目前较多的解决方法是对数据集中出现过的障碍物进行识别来检测可行驶区域,缺乏灵活性,因此本文提出了一种针对地铁站等室内平坦地面的可行驶区域检测方法,提高实用性.本文采用经典的MobileNetV3网络对采集到的前方图像进行分类,判断是否为地面区域.由于室内地面的地标、箭头等贴纸的影响,因此需要对非地面区域进一步判断,与常规的立体障碍物进行区分.本文利用连续帧之间的特征点匹配获得相机移动距离,并利用直线拟合计算斜率的方法达到区分立体障碍物与平面地标的目的.实验表明,本文提出的方法能较好地检测机器人前方可行驶区域,具有较高的实用价值.     

Operational active fire mapping and burnt area identification applicable to Mexican Nature Protection Areas using MODIS and NOAA-AVHRR direct readout data

Since 1999, the National Commission for the Knowledge and Use of the Biodiversity (CONABIO) in Mexico has been developing and managing the “Operational program for the detection of hot-spots using remote sensing techniques”. This program uses images from the MODerate resolution Imaging Spectroradiometer (MODIS) onboard the Terra and Aqua satellites and from the Advanced Very High Resolution Radiometer of the National Oceanic and Atmospheric Administration (NOAA-AVHRR), which are operationally received through the Direct Readout station (DR) at CONABIO. This allows the near-real time monitoring of fire events in Mexico and Central America. In addition to the detection of active fires, the location of hot spots are classified with respect to vegetation types, accessibility, and risk to Nature Protection Areas (NPA). Besides the fast detection of fires, further analysis is necessary due to the considerable effects of forest fires on biodiversity and human life. This fire impact assessment is crucial to support the needs of resource managers and policy makers for adequate fire recovery and restoration actions. CONABIO attempts to meet these requirements, providing post-fire assessment products as part of the management system in particular for satellite-based burnt area mapping. This paper provides an overview of the main components of the operational system and will present an outlook to future activities and system improvements, especially the development of a burnt area product. A special focus will also be placed on the fire occurrence within NPAs of Mexico.     

谈局域网的性能优化

在局域网运行和维护的过程中,网络管理员不仅要确保网络能够提供正常的服务,还要采取各种措施保证网络能够可靠、安全、高效地运行,从整个网络的角度提高网络的性能。     

认真深入做好前期工作确保三峡工程顺利兴建

三峡工程建设,无论是防洪,发电、航运其工程规模极其巨大,而且工程建设地处我国人口密集、经济相对较发达的长江干流上游最下部河段上;为此,工程建设的前期工作更应较全面深入周密细致,充分考虑方方面面的利害得失,正确地反映工程建设的经济效益。在开发性移民方针下,做好水库淹没损失的合理补偿和移民安置,不留后患。长江上游年年发生洪水造成灾害,工程设计应考虑在水库调洪运行中给上游带来的洪涝灾害淹没损失应得到相应的赔偿。执行《水法)对水资源的有偿使用经济收益的分配是一个有待探讨的问题。     

广西镇龙山金（银）矿的构造控制特征

本文阐述了广西镇龙山金（银）矿化集中区内主要断裂构造的基本特征,并指出,其中规模较大的,与矿化关系较密切的主要是近ＥＷ向,次为近ＳＮ向断裂,它们组合成线状,交叉状和放射状断裂带,并严格控制着区内岩浆岩、矿化带、矿脉、矿体和“富矿包“的空间展布。这对找矿评价和预测盲矿体都具有实际意义。     

Modeling deterministic echo state network with loop reservoir

Echo state network (ESN),which efficiently models nonlinear dynamic systems,has been proposed as a special form of recurrent neural network.However,most of the proposed ESNs consist of complex reservoi...     

中国西南易旱地区识别的探讨

利用中国西南地区13个气象站56年以上的长系列月降雨量资料,统计分析了降雨的多年变化、季节变化特征,以及连续少雨时间段事件,探讨了易旱区识别的定性定量分析方法,初步建立了气象易旱区识别指标及标准,将5个地区识别为易旱地区,5个地区识别为较易旱地区,3个地区识别为不易旱地区,将6个地区识别为易发长时间干旱地区,并对识别方法进行了讨论,为进一步的易旱区综合识别研究提出了建议。