Review of Secure Communication Approaches for In-Vehicle Network

In the connected vehicles, connecting interfaces bring threats to the vehicles and they can be hacked to impact the vehicles and drivers. Compared with traditional vehicles, connected vehicles require more information transfer. Sensor signals and critical data must be protected to ensure the cyber security of connected vehicles. The communications among ECUs, sensors, and gateways are connected by in-vehicle networks. This paper discussed the state-of-art techniques about secure communication for in-vehicle networks. First, the related concepts in automotive secure communication have been provided. Then we have compared and contrasted existing approaches for secure communication. We have analyzed the advantages/disadvantages of MAC and digital signatures for message authentication and compared the performance and limitations of different cryptographic algorithms. Firewall and intrusion detection system are introduced to protect the networks. The constraints and features of different intrusion detection approaches are presented. After that, the technical requirements for cryptographic mechanism and intrusion detection policy are concluded. Based on the review of current researches, the future development directions of the automotive network security have been discussed. The purpose of this paper is to review current techniques on automotive secure communication and suggest suitable secure approaches to implement on the in-vehicle networks.     

纯电骡子车开发及试制新方法应用

通过对比燃油汽车与纯电动汽车整车架构,分析燃油车改制纯电动骡子车的可行性。利用现有车型完成纯电动骡子车改制,不仅可以节省开发成本,还可以加快新产品升级换代。同时基于两种车型的差异性,制定相应的车型改制方案。阐述常见的改制内容与创新方法应用,为后续同平台新车型开发提供参考。     

摩托车和轻便摩托车用喇叭性能测试分析

摩托车和轻便摩托车用喇叭的性能测试主要包括基本声学性能和耐久性能测试,建立并执行统一、科学、合理的测试标准,是检测和评价喇叭品质的先决条件,是喇叭产品设计开发、合格检测及调试的基础,不同的试验方法,会给喇叭单品或装车性能的检测带来不同的结果,会给摩托车产品的生产、销售和出口造成一定的影响。     

浅谈新双积分法规下乘用车降油耗方案研究

乘用车燃油经济性是评价车辆性能的重要指标,通常以在一定循环行驶试验工况下,行驶100km所消耗燃油升数(单位为L/100km)作为评价指标。影响乘用车燃油经济性的因素很多,文章以公司某在研SUV为例,通过仿真及转鼓油耗测试手段,在保证车辆驾驶体验体验前提下,研究如何降低整车燃油经济性。     

基于机器人的车身焊接技术研究

目前,机器人在我国应用的范围相对比较广阔,在一定程度上能够取代人工的操作。工业机器人在实际的发展过程中是一种集机械以及电子计算技术等为于一体的人工智能的产品。本文研究分析了机器人的车身焊接技术研究。希望在一定的程度上能够为相关的工作人员提供一定的理论支持和实践参考。     

THE COLONIC TRANSIT TEST IN THE ASSESSMENT OF CHRONIC CONSTIPATION

In order to assess colonic motility of chronic constipation, colonic transit test was carried out in 34 patients with chronic constipation and in 20 healthy subjects. 20 radiopaque markers are ingested at 8 am before the day test, and plain abdominal films were obtained at 24 h, 48 h and 72 h. The normal value of colonic transit test was 16(80%), or more markers passed after 72 h. By means of transit time study, 34 constipated patients were classified into 2 groups: 12 normal transit patients and 22 slow transit patients. There was no difference in colonic transit time between normal transit patients and controls (P＞0.05). Patients with slow transit had more markers left in right colon, left colon and rectosigmoid colon at 48 h (P＜0.01, respectively) and 72 h (P＜0.01, respectively). According to the transit index, 22 slow transit patients were divided into 3 types: 10 cases colonic stasis, 8 cases outlet obstruction and 4 cases colorectal stasis. The study suggests that chronic constipated patients have abnormalbilities of colonic transit.     

城市客车助力离合器早期磨损的原因与处理

介绍城市客车助力离合器早期磨损的原因及处理方法.     

水运企业筹资风险的简易度量方法及资本结构优化

针对水运企业的特点，提出水运企业筹资风险的简易度量方法，并对筹资如何有利于优化水运企业资本结构进行探讨。     

A game-theoretic analysis of competition among container port hubs: the case of Busan and Shanghai 1

Countries throughout the world, and especially within Asia, are investing heavily in container port infrastructure in the hopes of capturing a larger share of global shipping activity for their economies. Many existing ports are emphasizing developing the capacity to serve as a hub port, building deepwater berths with large terminals to facilitate transfer of containers from feeder ships to mother ships for intercontinental transport. We develop a game-theoretic best response framework for understanding how competitor ports will respond to development at a focus port, and whether the focus port will be able to capture or defend market share by building additional capacity. We apply this model to investment and competition currently occurring between the ports of Busan and Shanghai.     

移动式非现场交通执法的证据采集与处理方法初探

在分析讨论移动与固定设备之间的差异性、移动式设备种类等问题的基础上,初步提出以图片为证据存储模式的移动式非现场执法的处理流程及方法,为相关工作提供参考。