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321.
报道了制备较高纯度有机电致发光材料8-羟基喹啉铝(Alq3)及其微晶的方法;通过X射线衍射谱(XRD)、红外吸收光谱、荧光光谱及扫描电子显微镜(SEM)测试分析,对Alq3微晶的结构和特性进行了表征。XRD证实了微晶主要成份为α-Alq3,并含有少量δ-Alq3;红外吸收光谱显示,Al-N键的伸缩振动模式对应谱峰407 cm-1,418 cm-1处,Al-O键的伸缩振动模式对应谱峰523 cm-1,542 cm-1,548 cm-1处,说明晶体中N、O分别与Al3+发生了配位,标定了微晶中喹啉环的存在;荧光光谱检测得到Alq3微晶在固态、(氯仿)溶液中的荧光发射谱峰分别位于500 nm、512 nm处;通过SEM观测了Alq3微晶的形貌,分析得到Alq3晶粒呈现六方形结构。 相似文献
322.
C4ISR互操作框架及信息关系模型研究 总被引:2,自引:0,他引:2
以“平台”为中心C4ISR体系结构在系统互操作和信息共享上存在一定的困难。在分析目前C4ISR系统体系结构和D4ICOE的基础上,提出了一个以“数据”为中心面向服务基于能力应用的C4ISR系统互操作框架,描述了互操作框架每个层次的作用和解决的问题,阐述了互操作框架与C4ISR系统集成之间的关系,并研究框架中的信息分类、信息流和信息关系。从信息组织、使用和验证的角度,提出了“V”信息关系模型。 相似文献
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325.
近年来,随着三维设计理念在船舶行业中的不断推广,船体结构三维建模方法逐渐普及。三维模型虽较二维图纸有着诸多的优势,但目前限于船级社、船东、部分中小船厂的实际情况,“三维设计+二维送审”的工作模式仍然是现阶段的主流形式。因此通过三维模型直接实现二维出图,仍具有十分重要的意义。本文主要介绍了一种基于CATIA V6的结构二维出图的关键技术,以平台原生出图功能为基础,结合CAA二次开发,提出中间模型技术,解决当前结构三维模型二维出图所面临的诸多问题,整体出图效果较CATIA原生出图功能有较大的提升。 相似文献
326.
In this paper, we present results regarding the experimental validation of connected automated vehicle design. In order for a connected automated vehicle to integrate well with human-dominated traffic, we propose a class of connected cruise control algorithms with feedback structure originated from human driving behavior. We test the connected cruise controllers using real vehicles under several driving scenarios while utilizing beyond-line-of-sight motion information obtained from neighboring human-driven vehicles via vehicle-to-everything (V2X) communication. We experimentally show that the design is robust against variations in human behavior as well as changes in the topology of the communication network. We demonstrate that both safety and energy efficiency can be significantly improved for the connected automated vehicle as well as for the neighboring human-driven vehicles and that the connected automated vehicle may bring additional societal benefits by mitigating traffic waves. 相似文献
327.
以连云港徐圩航道回淤观测项目为例,介绍HYPACK综合导航系统中进行水深数据处理时水深选择、成图水深检查校核及水深测量精度的分析功能,提出须注意的问题及解决方法,同时介绍快速绘制批量横断面图及冲淤图,以直观反应航道的冲淤变化规律. 相似文献
328.
Research on connected vehicle environment has been growing rapidly to investigate the effects of real-time exchange of kinetic information between vehicles and road condition information from the infrastructure through radio communication technologies. A fully connected vehicle environment can substantially reduce the latency in response caused by human perception-reaction time with the prospect of improving both safety and comfort. This study presents a dynamical model of route choice under a connected vehicle environment. We analyze the stability of headways by perturbing various factors in the microscopic traffic flow model and traffic flow dynamics in the car-following model and dynamical model of route choice. The advantage of this approach is that it complements the macroscopic traffic assignment model of route choice with microscopic elements that represent the important features of connected vehicles. The gaps between cars can be decreased and stabilized even in the presence of perturbations caused by incidents. The reduction in gaps will be helpful to optimize the traffic flow dynamics more easily with safe and stable conditions. The results show that the dynamics under the connected vehicle environment have equilibria. The approach presented in this study will be helpful to identify the important properties of a connected vehicle environment and to evaluate its benefits. 相似文献
329.
在季节性冰冻河流开江过程中,特别是武开江,较大体积的流凌会对堤防、护岸等水工建筑物构成严重威胁,甚至可聚集成冰塞或冰坝,造成水位短时抬高,导致漫滩或决堤,造成人民生命财产的损失。为探究流凌演进规律,有效预防流凌灾害,建立了流凌演进原型试验方法,开展松花江汤原河段流凌演进原型试验研究。通过RTK测量不同模型粒子的运动轨迹和撞击护岸现象,结合当地风速测量数据,探究流场要素、风速以及河道地形对流凌运动的影响;明晰流凌撞击护岸的影响因素以及堤防可能发生破坏的地点和形式。为揭示冰坝、冰塞形成机理提供理论参考,为堤防合理布局和维护提供指导依据。 相似文献
330.
The Cooperative Awareness Basic Service and Decentralized Environmental Notification Basic Service have been standardized by the European Telecommunications Standards Institute (ETSI) to support vehicular safety and traffic efficiency applications needing continuous status information about surrounding vehicles and asynchronous notification of events, respectively. These standard specifications detail not only the packet formats for both the Cooperative Awareness Message (CAM) and Decentralized Environmental Notification Message (DENM), but also the general message dissemination rules. These basic services, also known as facilities, have been developed as part of a set of standards in which both ISO and ETSI describe the Reference Communication Architecture for future Intelligent Transportation Systems (ITS). By using a communications stack that instantiates this reference architecture, this paper puts in practice the usage of both facilities in a real vehicular scenario. This research work details implementation decisions and evaluates the performance of CAM and DENM facilities through a experimental testbed deployed in a semi-urban environment that uses IEEE 802.11p (ETSI G5-compliant), which is a WiFi-like communication technology conceived for vehicular communications. On the one hand, this validation considers the development of two ITS applications using CAM and DENM functionalities for tracking vehicles and disseminating traffic incidences. In this case, CAM and DENM have demonstrated to be able to offer all the necessary functionality for the study case. On the other hand, both facilities have been also validated in a extensive testing campaign in order to analyze the influence in CAM and DENM performance of aspects such as vehicle speed, signal quality or message dissemination rules. In these tests, the line of sight, equipment installation point and hardware capabilities, have been found as key variables in the network performance, while the vehicle speed has implied a slight impact. 相似文献