A real-time multi-vehicle simulator for longitudinal controller design

This paper presents a new multi-vehicle simulator for platoon simulation. The main new feature of the developed simulator is a network structure for the real-time simulation of multiple vehicles, each with a detailed powertrain and engine model. It has a small initial delay, which is determined by the number of connected PCs, but the actual simulation is performed and displayed in real-time after this initial and one-time delay. Several longitudinal controllers, including a PID controller with gain scheduling, an adaptive controller, and a fuzzy controller, are also implemented in the simulator. Various system parameters can be modified interactively in the simulator screen, which is very useful for simulating a platoon of heterogeneous vehicles, in which vehicles with different dynamics and different longitudinal controllers may be involved. The simulator provides an excellent tool to develop vehicle longitudinal controllers and to study platoon behaviors. The developed simulator is also effective in testing the effects of nonlinearities neglected in the controller design phase, such as actuator delays and gear shifting schedule.     

Numerical Analysis of Thermal Distortion and Residual Stresses in H13 Steel Due to Vacuum Gas Quenching

IntroductionVacuumgasquenchinginvolvinghighpressuregasasacoolingmedium,is.anincreasinglypoPularheattreatffienttechniquefor1argesteeldieblocks,forexamPleHl3die.ItisconsideredessefltialtounderstandthentheeofthegasflowandtheinfiuencethishasontemPeratureprofilesandresultaflresidualstresseswithintheheattTeatedcomPonent.SimulatingthisprocessinvolvesthesimulationofgasflowinthefurnaceaswellasthesimulationofthethermalbehaviourofthecomPoneni.However,thereisnosinglecomPatersoftwarepackageavailabletot…     

基于优化支持向量机-混沌BP神经网络的基坑变形预测研究

为解决基坑变形预测精度低的问题,采用小波去噪分离基坑变形的趋势项及误差项序列,并利用多种优化的支持向量机对趋势项序列进行预测,采用混沌BP神经网络对误差项序列进行预测,将两者预测结果进行叠加即得到变形预测值,且可根据后期监测数据的更新,实时增加数据信息,达到跟踪预测的目的。经过3个实例检验,得出小波函数的去噪效果相对较优,且预测结果的相对误差均值均小于2%,验证了优化支持向量机-混沌BP神经网络模型的有效性,且该模型具有预测精度高、适用性强等优点,对掌握基坑变形的发展趋势及评价基坑的稳定性具有重要意义。     

基于游客需求的云南高速公路服务区文旅提升研究

随着交通和旅游消费结构的不断升级,云南高速公路对于旅游型服务区的建设需求不断加大,对既有和规划建设的高速公路服务区提出了文化旅游融合提升的更高要求.从游客需求侧的角度,采用RP/SP调查法收集多个云南高速公路服务区游客数据,分析云南高速公路服务区游客个人属性和出行特征,从5个维度分析评价游客关于服务区的水平感知度.研究...     

Examining the effect of speed,roadside features,and roadway geometry on crash experience along a rural corridor

This paper presents a current investigation into crash experience along a 15.7-mile rural corridor in southwest Montana with the aim of better understanding crash causal factors along the corridor. The study utilized ten years of crash data, geometric data, and observed freeflow speed data along the corridor. A systematic approach was used where every tenth of a mile was described in term of the crash experience, speed, alignment, and roadside features. Using bivariate and multivariate statistical anal-yses, the study investigated the crash experience along the corridor as well as some of the underlying relationships which could explain some of the crash causal factors. Results show a strong association between crash rates and horizontal curvatures even for flat curves that can be negotiated at speeds above the posted speed limit, per the highway design equations. Higher crash rates were also found to be associated with the difference between the observed free-flow speeds and the speed dictated by the curve radius or sight distance as per the design equations. Further, results strongly support the safety benefits of guardrails as evidenced by the lower crash rates and severities. The presence of fixed objects and the steepness of side slopes were also found to have an effect on crash rates and severities.     

Improving the stab-resistance performance of ultra high molecular weight polyethylene fabric intercalated with nano-silica-fluid

High performance fibers impregnated by shear thickening fluids （STFs） have been recognized as a kind of latent stab-resistant materials. In our work, the rheological properties of various nano-silica particles in different carriers were first investigated, some of which showed the typical characteristic of shear thickening phenomena. And then, the effects of add-on and surface hydrophilicity of silica particles, the type and concentration of the carriers were discussed in detail. It was found that the systems of hydrophilic silica in ethylene glycol, butylenes glycol and polyethylene glycol （PEG） demonstrated shear thickening; moreover, the reversibility of rheological behaviors of hydrophilic silica-PEG300 suspensions indicated energy dissipation existed within a circulation of shear stress. Furthermore, the detail mechanism of STF based nano-silica particles was explored and a process diagram was presented. Finally, the stab-resistance and morphology of cutting edge of ultra high molecular weight polyethylene （UHMWPE） fabric impregnated STF composites were investigated and the results were analyzed. The higher silica add-on was benefit to the improvement of the stab resistance of the composites.     

从对教材的评价探讨构建高职英语教材体系

本文从教材改革的角度出发,结合我院——"南京工业职业技术学院"(国家首批示范高职院)长期以来高职公共英语教材选用和使用的具体情况,采用问卷调查和访谈的方式,通过分析和评价不同教材的特点,探讨构建我院高职英语教材体系。     

THE EFFECT OF VITAMIN C INTAKE ON GLYCOHEMOGLOBIN MEASUREMENTS

ＴＨＥＥＦＦＥＣＴＯＦＶＩＴＡＭＩＮＣＩＮＴＡＫＥＯＮＧＬＹＣＯＨＥＭＯＧＬＯＢＩＮＭＥＡＳＵＲＥＭＥＮＴＳＦａｎｇＺｈｉｙｕ；ＳｕＭｉｎｇ，Ｒ．Ｒ．Ｌｉｔｔｌｅ，Ｈ．Ｍ．Ｗｉｅｄｍｅｙｅｒ，Ｄ．Ｅ．Ｇｏｌｄｓｔｅｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｉ...     

“基础英语＋行业英语”教学模式的改革

高职英语教学正由单一的＂基础英语＂向＂基础英语＋行业英语＂的模式转变,本文从高职英语如何定位、如何设计、如何实施等几方面阐述了新形势下高职英语教学改革新思路。     

高职计算机基础教育的困境与对策研究

以培养学生具备一定计算机应用能力为主要目的的高职计算机基础教育目前存在有因学生计算机知识基础不同出现的教学效率低下,因目标不明确和缺乏与专业之间的必要沟通造成的理论知识偏多、针对性不强,因一定程度上的教学资源缺乏造成的教学改革举步维艰、教学方式相对单一.要突破计算机基础教育的困境需从明确教学目标、改革考核方式,实行分层...