诊断学之未来

直至今日，医学诊断依然是一项艰苦的劳动高度密集型工作。血液与其它体液或组织样本被送往实验室进行分析，根据所采用分析方法的不同，有的需要几个小时，而有的则需要几天，甚至几个星期。现有技术往往花费昂贵，同时需要很长的等待时间，样本有可能发生变质，另外，如果取样小的话，则往往会导致错误的结果。通过多种方法获得数据很难被整合，而且很难对采样实施标准化。     

优秀汽车驾驶员的努力方向

随着我国社会主义经济建设的不断发展．机动车驾驶员人数在不断地增加，据有的城市统计．持机动车驾照人数占该城市人口的30％以上。全国驾驶员行业中又没有一个统一的优秀汽车驾驶员的评定标准．很难促进驾驶员自身的学习和进一步发展。为提高驾驶员的驾驶能力，笔者经过长期的思考，提出优秀汽车驾驶员应从以下几个方面进行努力．     

轿车常见漆膜缺陷分析与防治(上)

轿车常见漆膜缺陷的产生原因、预防与清除方法是涂装工作者需要了解和掌握的技术难题。例如，有许多漆膜缺陷，需要具有丰富操作经验的漆工才可以预防；对一般漆工来说，想让缺陷完全消灭在喷漆之前是不现实的。又如，缩孔、颗粒一直是高级技师的主攻难题，缺陷现象一旦产生，很难在短时间内找到缺陷原因。有时即使找到污染源，但消除污染源和返修需要几个星期，才能使车辆竣工。     

电子秤1.4e的实际应用及合理性

对于非自动电子衡器（主要数显秤），无论是检定规程、标准，还是国际建议都提出：其鉴别力不大于１．４ｅ，可是在实际工作中，变化一个检定分度值ｅ的鉴别力，有的只需要１．４ｅ的几分之一，有的要加到１．４ｅ附近，有的则真加或减到１．４ｅ砝码，衡器示值已变化了２个分度值ｅ。     

桑塔纳轿车发动机配气机构中的几个重要零件

桑塔纳轿车发动机的配气机构采用顶置凸轮轴的设计,凸轮轴直接通过杯状液压挺杆驱动进气门和排气门,见图示。至1993年年底,虽然桑塔纳轿车的国产零件的认可率和减货率分别超过了90％和80％,但发动机配气机构中的几个小零件至今尚未认可。其中有的零件未完成工装样品的试制工作,有的零件虽送样多次,却屡次过不了工装样品的验     

沥青混凝土桥面铺装早期病害原因分析和结构设计方法综述

本文对钢筋混凝土桥柔性桥面铺装的早期病害及其原因进行了分析与研究，在总结当前国内桥面铺装结构分析主要方法的基础上，通过理论分析，提出了用有限元进行结构分析时，需要重点研究的几个问题，指出了今后主要的研究方向。     

直读光谱法分析铸铁样品的实验研究

直读光谱法分析铸铁样品存在以下两个难点：一是直读光谱分析用的铸铁试样要求分析面的碳都以碳化物的形式存在，不能有游离石墨，即分析面必须完全白口，二是如何消除分析试样和标准样品由于冶金过程和某些物理状态的差异导致的分析误差。本文通过对铸铁样品和类型标准化样品的制备方法的研究，成功实现用直读光谱法进行铸铁炉前样品分析。     

用简单方法解决疑难问题

在日常的汽车维修工作中，有些故障看似很难解决，但如果开动脑筋，一些看似简单的方法却能解决疑难问题。下面是笔者处理过的几个故障实例，供同行们参考。     

汽车空调制冷剂泄漏的六种简易检测方法

夏季，制冷剂泄漏是汽车空调使用中最为常见的故障。制冷剂有的需要一年添加一次，有的可能2个月添加一次。制冷剂泄漏容易造成环境污染，另外增加车主维护车辆的费用和时间。现将车空调检漏的六种方法介绍如下。     

城市交通规划理论与模型

本文通过对城市交通规划现有方法的研究分析，提出我国交通规划面临的几个需要优先研究的问题。     

Driver recognition of a run-over accident

If a driver passes over a pedestrian lying on the road and flees, it is considered a crime. In several cases, even if the driver fled and was arrested, he/she often asserts that they did not know that the victim was a human being. However, the investigation agency often believes that a driver can certainly recognize when he/she passes over a person. Accordingly, such cases frequently lead to disputes due to the lack of criteria for recognizing when a driver was involved in run-over accidents. In this study, tests were conducted both to identify if drivers can recognize whether their vehicles passed over a person and to examine how they feel at the time. A silicon dummy, which was manufactured to have the same characteristic as the human chest, was used in this study. According to the method specified in ISO2631, the vibration delivered to the driver was measured, and eighteen participants drove a vehicle over the silicon dummy to experience how the vibrations felt. When the passenger car for the test ran over the dummy at speeds ranging from 10 km/h to 60 km/h, all participants recognized the delivered vibration, and the VDV that was delivered to the participants ranged from 1.81 m/s ^1.75 to 2.38 m/s ^1.75. The participants thought that the object they drove over was a stone or a piece of wood. This indicates that the driver certainly can recognize the vibrations generated from passing over a human chest even though it feels like a solid object.     

International and intercultural differences in arguments used against road safety policy measures

Policy measures in the field of road safety are not easily implemented for several reasons. Interventions can be undertaken in a multitude of policy areas, but it is often uncertain how effective the measures are. Moreover, policymakers may be reluctant to implement road safety policy measures because of the expected high costs and/or perceived low public support. To understand the arguments used against policy measures for road safety, a survey was conducted in ten countries (China, the United States, the United Kingdom, Belgium, Austria, Sweden, Greece, France, Nigeria, and Argentina). Respondents were presented with ten possible road safety measures and asked whether they would support or oppose them, what arguments their opinion was based on, and what the consequence of the measure would be on them individually. This paper describes the main findings of the research and then zooms in on three counterarguments: restriction of mobility, discrimination, and unjustifiability of state interventions, as well as on three of the measures considered—compulsory use of ISA systems, mandatory cycle helmets, and screening of older motorists. With this research, previous results on the level of public support have been confirmed, and new insights have been gained. If people feel safe when using a particular transport mode, they are less conscious of the need for additional or stricter measures affecting their transport mode. The perceived restriction of human liberties, fear of discrimination, and resistance to state interventions fuel opposition against measures. Moreover, people from different countries vary in what they consider fair and unfair, which is linked to the national culture and social organization. Even if a measure was perceived to be unfair from a certain perspective (e.g., discrimination), some respondents supported the measure. Our research also illustrates that even people who recognize that a measure would be effective might oppose it because they think it is not justified from at least one perspective, for instance, an excessive restriction of freedom.     

隧道地下水处治的国内外研究现状分析

为深入研究隧道设计、施工面临的地下水处治难题,为高压富水隧道设计、施工提供理论依据,对隧道地下水处治技术的现状进行分析。不同部门在不同时期和社会经济条件下,提出了不同规范和地下水处理措施。针对隧道工程设计、施工过程所遭遇的地下水问题,尤其是隧道衬砌水压力荷载问题,各行业部门在隧道(洞)工程支护结构设计中对富水地层地下水压力对支护结构的影响认识并不一致,尤其是对外水压力能否折减仍存在一定争议,对地下水作用的认识仍未达成共识。为此,对隧道地下水问题从概念和方法上进行研究,在研究现状及存在的主要问题分析基础上,提出了下一步研究思路。     

On Inverse Equations for Vehicle Dynamics

Instead of writing equations which when solved yield the response of a vehicle to an input such as the front wheel steer angle, one can often invert the equations so that a response quantity is specified as an input and a new set of equations is solved yielding the steer angle required as an output. Using these equations one can discover the input steer angle a driver would need to impose in order to accomplish a specific maneuver for various vehicles.

It is shown that there are many possible inverse equation sets and that the eigenvalues of the inverse equations are hard to interpret since they may have little to do with the vehicle parameters. The linear single-input single-output case is studied first to fix ideas using a simple example. For the bicycle model vehicle, it is shown that any vehicle may have unstable inverse equations depending upon the response quantity used. Extensions to nonlinear and multiple-input multiple output systems are discussed.     

Energy Flow in Active Attitude Control Suspensions: A Bond Graph Analysis

Fully active ground vehicle suspensions which completely replace the passive spring and damper elements with a force generating actuator have required a significant amount of power. Alternative systems which retain compliant elements to handle high frequency isolation but include active elements to control the vehicle body attitude have been developed to reduce the power requirements. These suspensions are called “low bandwidth” or “fast load leveler” systems and they often incorporate semi-active dampers which produce high frequency controllable forces with low power requirements. Here, two contrasting attitude control systems are studied to show that actuator power can be significantly reduced if the actuator is used to vary a lever ratio instead of being used to compress the suspension spring directly. Both types of systems have been successfully implemented in prototype form. Bond graphs for idealized versions of the suspensions show clearly the significant differences in actuator power and energy requirements even though the abstract mathematical structures of the two systems are remarkably similar. Computer simulations confirm the analytical results.     

基于WLF公式确定DSR中不同平行板的温度适用范围

动态剪切流变仪不仅可以用来对沥青的路用性能进行分级,也可以在大温度范围内测定沥青的性能。采用动态剪切流变仪对沥青材料进行试验时,不同平行板在相同试验条件下对同种试样进行试验的数据不一定相同,并且不同半径的平行板有各自的温度实用范围,本文从时间温度等效原理入手,采用数据分析软件,对采用不同平行板进行试验得到的频率-模量曲线进行拟合,从而得到模量主曲线,确定出不同平行板的试验结果在一定频率范围内的互用范围。采用WLF公式计算出不同温度条件下对应的基准温度TS值,研究结果表明:在沥青模量一定的范围内,8 mm平行板与25 mm平行板相比更适合20℃以下的动态剪切试验,而在20℃以上,二者可以互用,这对于以后的研究提供了不同条件下选择仪器的一个参考。     

摩托车车架弯管技术探讨

摩托车车架弯管件在弯曲过程中,会出现椭圆变形、壁厚变薄和回弹等现象。基于对上述现象产生原理的分析和相应的试验,提出一些切合实际的解决方法:弯管件设计时,尽量增大弯管件的弯曲半径,这样有助于减小椭圆变形率、壁厚变薄率;在生产时选用合适的芯棒,可以有效减小椭圆变形;按公式计算弯曲模的半径;按公式或20/120方法计算角度回弹值来修正弯管机的加工程序。     

On Inverse Equations for Vehicle Dynamics

Abstract

Instead of writing equations which when solved yield the response of a vehicle to an input such as the front wheel steer angle, one can often invert the equations so that a response quantity is specified as an input and a new set of equations is solved yielding the steer angle required as an output. Using these equations one can discover the input steer angle a driver would need to impose in order to accomplish a specific maneuver for various vehicles.

It is shown that there are many possible inverse equation sets and that the eigenvalues of the inverse equations are hard to interpret since they may have little to do with the vehicle parameters. The linear single-input single-output case is studied first to fix ideas using a simple example. For the bicycle model vehicle, it is shown that any vehicle may have unstable inverse equations depending upon the response quantity used. Extensions to nonlinear and multiple-input multiple output systems are discussed.     

The evaluation of tactile ground surface indicator condition and effectiveness on the sidewalk in Yogyakarta City,Indonesia

Installed on sidewalks, Tactile Ground Surface Indicators (TGSI) aims to help people with visual impairments so that they can be more independent, mobile, confident, and safe when passing the road on which they often or even first-time pass. Improper installation of TGSI will make people with visual impairments confused and potentially cause accidents. This study aims to evaluate and discuss the existing conditions of TGSI installations on secondary arterial roads in Yogyakarta City, Indonesia and their impact on people with visual impairments. A field survey was conducted to answer this research question through measurements and photo documentation to discover the length of the installed TGSI and the condition of the existing of TGSI installation. The results indicated that out of the 14 secondary arterial road segments in Yogyakarta City, only 6 road segments or 43% of the roads had been installed with TGSI and the road sections had not been connected between each other. In addition, the major issues of existing TGSI installation are low connectivity, dangerous paths, inconsistent installations, and sidewalk facilities that did not consider people with visual impairments. Therefore, it can be said that the use of the TGSI facilities on secondary arterial roads in Yogyakarta City, Indonesia, has not been effective and dangerous for people with visual impairments.