It is proposed to set a simple curve between two straight roads. what were the important elements required for setting and on the ground.

Published under licence by IOP Publishing LtdISPECEIOP Conf. Series: Journal of Physics: Conf. Series 1187 (2019) 042073IOP Publishingdoi:10.1088/1742-6596/1187/4/0420731A systematic review: Road infrastructure requirement forConnected and Autonomous Vehicles (CAVs)Yuyan Liu1,2, Miles Tight2, Quanxin Sun1 and Ruiyu Kang31School of Traffic and Transportation, Beijing Jiaotong University, Beijing 100044,China2School of Engineering, University of Birmingham, Birmingham B15 2TT, UnitedKingdom3Drycoolers Inc, Oxford MI 48371, United StateE-mail: [email protected]. There is currently a significant worldwide interest in Connected and AutonomousVehicles (CAVs), not least for the reason that their realisation and implementation wouldtransform the nature of transportation and provide new impetus for social and economic change.However, the road to support CAVs has not been well prepared, at the risk of leaving potentialbarriers to CAVs deployment. This paper, therefore, focuses on the gap between current statusand future requirements of CAV-compliant road infrastructures, summarizes the possibilities ofupgrades, and proposes a three-phase road infrastructure upgrade plan that evolves over time.The first phase is maintenance, followed by a segregated-infrastructure expansion phase leadingto phase three which involves the application of simplified standard. The paper is based on anextensive literature review and evidence synthesis and is intended as a stimulus for future studyand further debate. For objectiveness, the proposal is general but would need to be refined, whenput into practice, to cater for specific implementation contexts.1. IntroductionConnected and Autonomous Vehicles (CAVs) use a variety of devices including radar, lidar, camerasas sensors, to perceive their surroundings [1]. However, current shortcomings in the perception processmay need to be overcome through well-prepared road infrastructure [2]. Otherwise, the realisation of afuture with increased mobility for disabled people, a reduction of road accidents caused by human errorand the mitigation of pollution as well as congestion could remain but a distant aspiration.Currently, the research into road infrastructure to support CAVs is still in its infancy. Even thoughsome reports and white papers containing ‘scattered views’ are slowly being released along with today’sCAVs testing projects (e.g. TSC in the UK), the planning and guidance documents used by the highwayauthorities (e.g. DMRB and WebTAG in the UK) have not taken CAVs into account yet [3]. Therefore,the aim of this paper is to assess the requirement for existing road infrastructure to support CAVs. andthe review question is proposed as:• How should the road infrastructure be upgraded to accommodate and support CAVs?Following on from the Introduction, the paper is laid out as follows: Section 2 provides essentialbackground information of both CAVs and the road. Section 3 is the detailed literature review process,followed by Section 4, which summarises the literature findings into two categories, namely the

What did the speaker notice about the two roads?

. Which one of the following is not influence and control design of Geometric design of Highway?1 pointDesign speedEconomic & Environmental ConsiderationsVehicle size and performance characteristicsStopping Sight DistancesNature of terrain

The changes in gradient and vertical curve are covered under which type of alignment?a.Highway specificationsb.Vertical alignmentc.Horizontal alignmentd.Geometric design

To help with vehicle stability, the outer edge of a road in a curve is raised with respect to the inner edge. This is called superelevation and is specified as the difference in elevation divided by the width of the road. It needs to be higher for faster speeds and sharper curves.The radius of a curve is the radius of the section of a circle along the middle of the road where the curve is constant. See Figure 1 for a drawing of this.Figure 1: Section of a circle along the middle of a road with radius 𝑅.In some cases the curve may need a lower speed limit than straight portions of the road. The superelevation shouldn’t be more than about .12 to keep vehicles from sliding off the road in slippery conditions.Your job is to calculate the maximum speed on a curve given the radius of the curve and the superelevation.The maximum speed is given by this formula:𝑉=(𝑅∗(𝑆+.16))/.067,where 𝑉 is the max speed in miles per hour, 𝑅 is the radius of the curve in feet, and S is the superelevation.InputThe input is a series of lines terminated by end-of-file. Each line will be a test case consisting of 𝑅 and 𝑆 separated by whitespace. 𝑅 will be an integer greater than 99 and less than 5281 and 𝑆 will be a real number greater than .009 and less than 1.0. Neither will have leading zeros. There are at most 100 lines in input.OutputFor each test case output the maximum speed rounded to the nearest integer. It is guaranteed the answer before rounding will not be within 10−3 of a half-integer value.Sample Input 1 Sample Output 11433 .091433 .122000 .09600 .1273778650