为了解决Vehicle to Everything(V2X)毫米波通信系统延时高、链路易阻塞等问题,基于车辆和用户终端周围环境状态信息的感知,提出一种视觉辅助的能效最大阻塞预测方法。利用视觉感知模型实现系统对目标用户以及周围障碍物的精准感知,结...为了解决Vehicle to Everything(V2X)毫米波通信系统延时高、链路易阻塞等问题,基于车辆和用户终端周围环境状态信息的感知,提出一种视觉辅助的能效最大阻塞预测方法。利用视觉感知模型实现系统对目标用户以及周围障碍物的精准感知,结合深度强化学习设计了一种融合特征和时间注意力的DA-DBLSTM网络预测未来链路阻塞到达时间,与传统注意力相比,该融合注意力不仅可以关注每个时间单元中的不同特征,而且关注不同时间单元的时序信息,使检测效果更优。仿真和分析结果表明,提出的DA-DBLSTM网络预测链路阻塞效果明显,在均方误差(Mean Square Error,MSE)、均方根误差(Root Mean Square Error,RMSE)、平均绝对误差(Mean Absolute Error,MAE)和平均绝对百分比误差(Mean Absolute Percentage Error,MAPE)方面均优于现有方法。展开更多
车路协同是信息通信、智能汽车、交通运输和交通管理等行业深度融合的新型产业业态,处于人工智能、5G和交通三大国家战略的交汇点。5G V2X无线通信技术作为关键赋能型技术,将有助于构建“路-云-车-人-网”协同的车联网生态体系。该文首...车路协同是信息通信、智能汽车、交通运输和交通管理等行业深度融合的新型产业业态,处于人工智能、5G和交通三大国家战略的交汇点。5G V2X无线通信技术作为关键赋能型技术,将有助于构建“路-云-车-人-网”协同的车联网生态体系。该文首先介绍车路协同系统的定义、主要建设内容及其典型应用场景。其次以应用牵引,针对5G新空口-车用无线通信(NR-V2X)技术中的直连通信应用于自动驾驶场景的具体需求进行研究,给出不同业务场景下对通信性能和安全的需求说明。最后,针对车路协同系统低时延、高可靠和高并发的系统需求,分析5G NR V2X物理层、资源分配、拥塞控制和Qos与安全设计的相关原理。展开更多
Purpose: To report an unusual case of retinal microvasculopathy secondary to mixed connective tissue disease (MCTD) on a background history of fragile-X syndrome (FXS). Methods: Case report and literature review. Resu...Purpose: To report an unusual case of retinal microvasculopathy secondary to mixed connective tissue disease (MCTD) on a background history of fragile-X syndrome (FXS). Methods: Case report and literature review. Results: A cotton wool spot was discovered in a 29-year-old female who presented with an ischaemic digit secondary to Raynaud’s phenomenon. She also has a background history of MCTD and FXS. Fundus examination and automated perimetry findings were normal. Magnet resonance imaging and computed tomography aortogram did not demonstrate any evidence of vasculitis in the head and neck. She was tested positively for U1-ribonuclear peptide. Interestingly, the re-distribution of Fragile-X related gene 1 has been suggested to trigger autoimmune responses in experiments. This finding makes the case peculiar as it suggests an alternate explanation for this patient’s clinical findings. Conclusion: Retinal vasculopathy is a rare complication of MCTD. The background history of FXS potentially highlights an alternate autoimmune pathogenetic mechanism.展开更多
In order to solve negative phase sequence problem of V connection transformer in the high speed and heavy haul electrical railway of China, the hybrid compensative co-phase traction power supply system which based on ...In order to solve negative phase sequence problem of V connection transformer in the high speed and heavy haul electrical railway of China, the hybrid compensative co-phase traction power supply system which based on passive and active compensation is proposed. Firstly, There construction and capacity distribution are analyzed, and the compensation current of active equipment is gave;Second, the feature of the hybrid compensative schemes are discussed. In the end, the related simulation results have confirmed the effectiveness of the compensation schemes in this paper.展开更多
文摘车路协同是信息通信、智能汽车、交通运输和交通管理等行业深度融合的新型产业业态,处于人工智能、5G和交通三大国家战略的交汇点。5G V2X无线通信技术作为关键赋能型技术,将有助于构建“路-云-车-人-网”协同的车联网生态体系。该文首先介绍车路协同系统的定义、主要建设内容及其典型应用场景。其次以应用牵引,针对5G新空口-车用无线通信(NR-V2X)技术中的直连通信应用于自动驾驶场景的具体需求进行研究,给出不同业务场景下对通信性能和安全的需求说明。最后,针对车路协同系统低时延、高可靠和高并发的系统需求,分析5G NR V2X物理层、资源分配、拥塞控制和Qos与安全设计的相关原理。
文摘Purpose: To report an unusual case of retinal microvasculopathy secondary to mixed connective tissue disease (MCTD) on a background history of fragile-X syndrome (FXS). Methods: Case report and literature review. Results: A cotton wool spot was discovered in a 29-year-old female who presented with an ischaemic digit secondary to Raynaud’s phenomenon. She also has a background history of MCTD and FXS. Fundus examination and automated perimetry findings were normal. Magnet resonance imaging and computed tomography aortogram did not demonstrate any evidence of vasculitis in the head and neck. She was tested positively for U1-ribonuclear peptide. Interestingly, the re-distribution of Fragile-X related gene 1 has been suggested to trigger autoimmune responses in experiments. This finding makes the case peculiar as it suggests an alternate explanation for this patient’s clinical findings. Conclusion: Retinal vasculopathy is a rare complication of MCTD. The background history of FXS potentially highlights an alternate autoimmune pathogenetic mechanism.
文摘In order to solve negative phase sequence problem of V connection transformer in the high speed and heavy haul electrical railway of China, the hybrid compensative co-phase traction power supply system which based on passive and active compensation is proposed. Firstly, There construction and capacity distribution are analyzed, and the compensation current of active equipment is gave;Second, the feature of the hybrid compensative schemes are discussed. In the end, the related simulation results have confirmed the effectiveness of the compensation schemes in this paper.