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1.
基于视频的路况能见度检测系统的设计与实现   总被引:3,自引:1,他引:2  
能见度涉及高速公路的安全行车,现有气象能见度仪本身样本空间受限,且价格十分昂贵而难以沿途布设,不能真实反映路段的能见度及其分布。为此,提出了基于路况监控视频的能见度检测系统的设计方案,阐述了视频能见度检测的基本原理,给出系统的总体框架,重点研究了能见度检测模块的实现:通过带有距离信息的目标图像块的选取、图像块的匹配、边缘特征的提取,空间亮度对比的计算、曲线拟合得到能见度信息。系统已在江苏省高速公路宁通、宁常路段试用,系统运行良好,检测结果与人眼观察误差符合国际规定(+10%),并具有较好的鲁棒性。  相似文献   

2.
用于辅助和自动驾驶系统的各种传感器中,相机和激光雷达的感知性能受天气影响较大,而车载毫米波雷达是一种低成本且几乎不受天气影响的全天候工作器件,对于运动的物体,可提取丰富的多普勒信息。随着雷达技术和开源标注数据集的发展,基于底层雷达数据的目标检测已经成为一个非常有前景的领域。为解决车载毫米波雷达数据的角度分辨率低导致的目标检测和定位不准确的问题,并提升毫米波雷达目标检测的性能,提出了一种基于先验框距离约束的3D卷积毫米波雷达目标检测方法,以实现多种动态目标的检测及分类。在本文方法中,通过设计3D ResNet的特征提取器来表征距离-角度-多普勒张量中的目标信息,解决现有的模型因忽略来自原始3D雷达信号的多普勒信息而表征不足的问题;其次,添加了绝对距离损失函数来训练模型,克服距离对目标呈现的影响,提高目标检测的准确性和鲁棒性;此外,还提出了分距离单元区间重新设置先验框的方法,解决现有方法中先验框设计不合理的问题。所提出的模型在RADDet数据集上进行训练以及测试,实验结果表明:与目前的最先进的方法相比,本文模型在IoU阈值为0.1、0.3、0.5、0.7时均达到最优,其中IoU为0.1和0...  相似文献   

3.
针对风雨特殊天气数据样本少、负荷变化异常的特点,提出了一种新的负荷与气象敏感度分析方法。首先,基于灰色关联度理论,提出了一种基于相关系数变化率的负荷主要影响因素选择方法;其次,根据不同的气象条件区间,建立负荷与气象的多元线性回归关系,得到了更准确的负荷随气象因素变化的敏感度;最后,利用所提方法对海口电网的负荷和气象因素进行了敏感度分析,揭示了海口电网负荷随气象变化的规律,对提高台风等特殊风雨天气下电网的负荷预测精度和运行安全性具有实用参考价值。  相似文献   

4.
This paper provides a detailed investigation into two potential forms of onboard road departure warning systems. A method known as time-to-lane-crossing (TLC) is compared with rumble strips placed a fixed distance from the road edge, and is found to provide enhanced performance over such static rumble strips in terms of reduced false warnings and increased warning anticipation. A new approach, called the variable rumble strip (VRBS), is proposed, which is an onboard electronic implementation of the static rumble strip where the warning threshold is allowed to vary according to the risk of the vehicle departing the road. Performance of the fuzzy-logic-based VRBS system is similar to that of the TLC-based approach, but requires less sensor information, making it more feasible in a vehicle application. Performance is measured in terms of hits, misses, and false alarms based on a validation warning set comprised of either static rumble strip generated warnings or by a warning set generated by subjective interpretation of the road departure criticality. The algorithms are tested on 2-h driving simulator runs by 12 drivers. This paper also includes an extension to the VRBS system involving the use of an estimate of driver lane-keeping performance to alter the VRBS threshold adjustment.  相似文献   

5.
分析了影响光伏出力的气象因素,结合光伏系统实际运行数据和气象信息,提出一种基于天气类型聚类和LS—SVM的光伏出力预测模型。选取太阳辐照时间、温度、相对湿度等作为气象特征向量,通过计算各向量的加权欧氏距离,筛选出最佳聚类集合,确定训练样本,使样本数据能更好地反映待预测日的实际气象信息。取最佳聚类日气象特征、相应光伏出力及待预测日气象特征输入训练好的LS—SVM模型,输出为待预测日对应时刻的光伏出力。最后通过实际算例分析、评估,验证了所提模型和算法的有效性,并通过增加样本数据点获得了更加精确的预测结果。  相似文献   

6.
降雨导致交通事故频发.分析了降雨对能见度、道路摩擦系数等产生的影响,比较AASHTO,NCHRP停车视距模型,通过停车视距模型得到了不同水膜厚度,不同能见度下的安全限速值.在降雨天气下,对易发生交通事故的路段提出了可变限速控制,采用逐级限速的标准,使汽车从高速区即将驶入异常事故多发路段时之前可以有充分的时间和距离来降低车速,用来提高汽车在雨天行驶的安全性,可以有效避免交通事故的再次发生,提高高速公路对异常情况的应变能力.  相似文献   

7.
Adaptive fuzzy control for inter-vehicle gap keeping   总被引:2,自引:0,他引:2  
There is a broad range of diverse technologies under the generic topic of intelligent transportation systems (ITS) that holds the answer to many of the transportation problems. In this paper, one approach to ITS is presented. One of the most important research topics in this field is adaptive cruise control (ACC). The main features of this kind of controller are the adaptation of the speed of the car to a predefined one and the keeping of a safe gap between the controlled car and the preceding vehicle on the road. We present an ACC controller based on fuzzy logic, which assists the speed and distance vehicle control, offering driving strategies and actuation over the throttle of a car. The driving information is supplied by the car tachometer and a RTK differential GPS, and the actuation over the car is made through an electronic interface that simulates the electrical signal of the accelerator pedal directly to the onboard computer. This control is embedded in an automatic driving system installed in two testbed mass-produced cars instrumented for testing the work of these controllers in a real environment. The results obtained in these experiments show a very good performance of the gap controller, which is adaptable to all the speeds and safe gap selections.  相似文献   

8.
A decentralized communication and control system is presented for driving assistance and automation along designated highway segments. This paper is based on a hybrid dynamical model describing vehicular motion, and the structure of a safe controller is presented. A ranging and communication system provides information for a vehicle and its nearest neighbors. The system is capable of handling sudden changes of regime, overtakes, reentries, as well as a number of maneuvers dictated by safety requirements under partially unpredicted events. A user-friendly interface, based on a palmtop computer, is developed to assist drivers visually and acoustically  相似文献   

9.
This paper presents a method of constructing a probability distribution for the capacity assistance available to a system from its neighboring interconnected areas. The proposed method is capable of dealing with arbitrarily connected networks. Additionally the method considers the correlation between area loads. A discrete joint distribution is used for the multi-area load model, and the capacity assistance distribution is constructed in the form of a joint probability distribution between the assistance levels and the load vectors. The uses of such a joint distribution matrix as a reliability analysis tool as well as an operations planning tool are described. The method is tested using the IEEE-RTS, with 3-area, 4-area, 5-area and 10-area interconnections  相似文献   

10.
利用多普勒天气雷达的探测资料,根据TREC算法自动识别灾害性天气种类并分区,自动进行客观的短时临近预警预报。生成的预警产品通过与地理信息系统(GIS)的有机结合,实现短时灾害性天气的精确预报,并通过空间分析服务引擎准确定位电网设备。  相似文献   

11.
User requirements for the performance of Global Navigation Satellite System (GNSS)-based road applications have been significantly increasing in recent years. Safety systems based on vehicle localization, electronic fee-collection systems, and traveler information services are just a few examples of interesting applications requiring onboard equipment (OBE) capable of offering a high available accurate position, even in unfriendly environments with low satellite visibility such as built-up areas or tunnels and at low cost. In addition to that, users and service providers demand from the OBEs not only accurate continuous positioning but integrity information of the reliability of this position as well. Specifically, in life-critical applications, high-integrity monitored positioning is absolutely required. This paper presents a solution based on the fusion of GNSS and inertial sensors (a Global Positioning System/satellite-based augmentation system/inertial navigation system integrated system) running an extended Kalman filter combined with an interactive multimodel method (IMM-EKF). The solution developed in this paper supplies continuous positioning in marketable conditions and a meaningful trust level of the given solution. A set of tests performed in controlled and real scenarios proves the suitability of the proposed IMM-EKF implementation as compared with low-cost GNSS-based solutions, dead reckoning systems, single-model EKF, and other filtering approaches of the current literature.  相似文献   

12.
特高压输电线路跨越距离长,易受不同气象条件的影响,实现特高压输电线路在不同气象条件下的电气可靠性实时评估与预警对保障电力系统稳定可靠运行具有重要意义。分析了输电线路污闪和风偏闪络的机理,将气象数据引入特高压输电线路电气可靠性实时评估与预警中,结合未来1~72h数值天气预报的结果,建立了基于气象参数的特高压输电线路污闪、风偏风险实时评估与预警模型,预测特高压输电线路在不同气象条件下的污闪和风偏闪络电压,进而得到特高压输电线路在不同气象条件下的污闪和风偏闪络的风险等级,实现评估与预警。  相似文献   

13.
This paper demonstrates the role of connectivity, a concept originally developed by Newnham two decades ago, in improving image quality of infrared (IR) imaging systems by enhancing the thermal modulation transfer function (MTF). IR imaging in the medium wavelength range (7.5 to 14 m), corresponding to the thermal black body maximum near room temperature and to the atmospheric window, is desirable for a wide range of applications. Night vision, target recognition, reconnaissance, driving aids, and navigation in foggy and poor visibility weather are among the applications of this technology. 1:3 arrays fabricated from ceramic barium strontium titanate (BST) have made it possible to produce compact, low-cost, uncooled infrared cameras that are capable of delivering television quality images.  相似文献   

14.
引入越限惩罚型变权熵理论,建立能够综合考虑雷电、降雨、风、气温、相对湿度等多种天气因素的复杂天气风险源模型,利用该模型计算相应的综合气象因子;基于电气设备的健康指数模型,提出天气风险源修正架空线路故障率的方法;采用非序贯蒙特卡罗仿真,对考虑复杂天气风险源的电力系统可用输电能力进行评估。采集我国南方沿海地区实际气象数据,并在IEEE 118节点系统进行仿真,结果表明所提方法是有效的。  相似文献   

15.
ACC+Stop&go maneuvers with throttle and brake fuzzy control   总被引:1,自引:0,他引:1  
Research on adaptive cruise control (ACC) with Stop&Go maneuvers is presently one of the most important topics in the field of intelligent transportation systems. The main feature of such controllers is that there is adaptation to a user-preset speed and, if necessary, speed reduction to keep a safe distance from the vehicle ahead in the same lane of the road, whatever the speed. The extreme case is the stop and go operation in which the lead car stops and the vehicle at the rear must also do so. This paper presents the development of an ACC system and related experiments. The system input information is acquired by a real-time kinematic phase differential global positioning system (GPS) (i.e., centimetric GPS) and wireless local area network links. The outputs are the variables that control the pressure on the throttle and brake pedals, which is calculated by an onboard computer. In addition, the car control is based on fuzzy logic. The system has been installed in two mass-produced Citroe/spl uml/n Berlingo electric vans, in which all the actuators have been automated to achieve humanlike driving. The results from real experiments show that the unmanned vehicles behave very similarly to human-driven cars and are very adaptive to any kind of situation at a broad range of speeds, thus raising the safety of the driving and allowing cooperation with manually driven cars.  相似文献   

16.
由于历史数据和天气因素对光伏出力预测的影响较大,提出了一种日特征相似度与形状相似度相结合的方法,分时段地预测光伏发电功率。该方法首先采用欧式距离法对气象类型进行细分,然后在不同时间段中分别利用两种相似日选取算法选取历史相似日,再利用其对应时段的历史功率值及气象数据,采用BP神经网络对预测日相应时段的功率进行预测,结果表明该方法的预测精度有明显提高。  相似文献   

17.
基于GIS的电网气象灾害监测预警系统的研制   总被引:1,自引:0,他引:1  
基于GIS的电网气象灾害监测预警系统接入多种形式的气象源数据,将气象灾害与电网设备GIS数据进行关联分析,建立电网运行领域可靠的灾害性天气预警模型,对涉及的电网设备进行预警。采用多种数据解析技术将XML、二进制等数据文件解析为预设格式数据;采用时序图技术实现各种气象信息的时序播放,展现其变化趋势;利用基于等值面提取形成的气象色斑图展示气象要素的地区分布情况和变化趋势。系统的研究与应用,对科学安排电网规划、运行,有效实现电力设施的防灾、减灾及电网安全运行精细化管理,具有重要作用和社会价值。  相似文献   

18.
以电网迎峰度冬和迎峰度夏为背景,将电网负荷中的气象敏感负荷作为研究对象,对负荷预测气象指标进行分析,结合天气预报准确性分析,得出累积温度指标的适用性范围。分别采用基于累积温度指标的预测方法和基于综合气象指标的预测方法对气象敏感负荷进行预测,并针对大幅度升温/降温以及天气转化情况时对预测方法进行改进,提出在累积温平均温度变化超过2℃时,宜采用基于累积温度在平日预测时采用变化和平均温度变化加权指标进行负荷预测,在晴雨转换时采用修正后的综合气象指标预测法的综合气象敏感性负荷预测方法。实际算例和应用表明,该预测算法具有更高的准确度,为目前负荷预测提供一定依据。  相似文献   

19.
碳纳米管场致发射显示器因其特有的性质和优良的性能赢得了普遍关注.场致发射显示器的驱动电路设计与制作是场致发射显示器的一个重要部分,使用非专用驱动系统导致驱动部分体积庞大、连线复杂.本文讨论一种驱动碳纳米管场致发射显示器的新方式.由于碳纳米管可以生长在硅基底上,从而可将驱动电路预先制作在硅基底上,然后再利用室温下生长碳纳米管的方法,将碳纳米管和电路集成在同一硅基底上.驱动系统和发射部分集成在一起,可达到使FED轻薄的设计要求.  相似文献   

20.
由于光伏功率波动特征与天气类型紧密相关,且光伏功率短期预测存在功率波动过程预测精度低、气象因素与功率波动过程相关性弱的问题,文中提出了一种基于天气分型的短期光伏功率组合预测方法。首先,基于气象因素与光伏功率波动特征的关联性,将天气过程划分为5种类型,并基于变分模态分解算法将光伏功率分解为类晴空过程和波动过程。然后,利用Granger因果关系算法筛选出与各天气类型下光伏功率波动过程密切相关的关键气象因子。最后,建立基于天气分型的短期光伏功率组合预测模型。模型充分考虑了深度学习算法的特异性,对光伏功率类晴空过程与各天气类型下的光伏功率波动过程进行分类预测。仿真结果表明,文中所提出的短期光伏功率预测方法能够显著提升短期光伏功率预测的精度。  相似文献   

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