Auto-scanning and visualizing system for the acoustic field of transducer

This paper presents an automatic scanning and visualizing system for ultrasound field of a planar piston transducer. This system consists of a water tank with wedge absorber, stepper motors driver, system controller, a planar piston transducer, a needle-type hydrophone and data processing software. Our software realizes the processing and displaying of ultrasonic data, which are acquired by adjusting accurately positions of the hydrophone and transducer that are driven by stepper motors. And the ultrasonic field is represented by employing 1D, 2D or 3D graphs of data, respectively. Experimental results show that this auto-scanning and visualizing system provides a more spatial structure of ultrasonic field and reveals a more characteristic of ultrasonic beam radiated by the planar piston transducer.     

基于WINCE5.0的差分接口LCD驱动的实现

该文以S3C2440A为核心,以友达G065VN01 V2型号的差分信号接口TFT_LCD为例,阐述了LCD控制器的工作原理,实现了从控制器的CMOS/TTL信号到LCD接口LVDS(低压差分信号)的转换;同时介绍了在嵌入式操作系统WINCE 5.0下LCD驱动程序的结构模型,以及如何在S3C2440A平台上实现LCD驱动移植.     

无线遥控循迹机器人的设计与实现

本文介绍了整个测量系统的组成和原理,并进行了系统硬件和软件设计,包括单片机最小系统、L298N电机驱动电路、RS232串口电路、循迹电路等的设计;软件设计包括数据处理部分、遥控部分和循迹部分等的设计。在AT89S52单片机中,以RS232串口和XL02～232API无线模块作为传输通道,实现了通过电脑遥控控制机器人运行以及自动寻迹的功能,具有实时性好,工作效率高等优点。     

Participation of Danish and immigrant cleaners in a 1-year worksite intervention preventing physical deterioration

Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group.     

Haptic gas pedal feedback

Active driver support systems either automate a control task or present warnings to drivers when their safety is seriously degraded. In a novel approach, utilising neither automation nor discrete warnings, a haptic gas pedal (accelerator) interface was developed that continuously presents car-following support information, keeping the driver in the loop. This interface was tested in a fixed-base driving simulator. Twenty-one drivers between the ages of 24 and 30 years participated in a driving experiment to investigate the effects of haptic gas pedal feedback on car-following behaviour. Results of the experiment indicate that when haptic feedback was presented to the drivers, some improvement in car-following performance was achieved, while control activity decreased. Further research is needed to investigate the effectiveness of the system in more varied driving conditions. Haptics is an under-used modality in the application of human support interfaces, which usually draw on vision or hearing. This study demonstrates how haptics can be used to create an effective driver support interface.     

双车道公路驾驶员超车行为试验研究

通过利用高精度全球定位系统(global positioning system,GPS)动态数据采集仪,结合驾驶员超车过程的感受度,设计了双车道公路上测量可回车车头时距和可超车车头时距的试验方案,获得的实验数据可为研究双车道公路通行能力、驾驶员超车行为、设计超车视距以及构建智能交通系统提供实测数据依据.     

用于爆胎车辆仿真的驾驶员模型

分析了驾驶员模型在汽车爆胎仿真应用中存在的问题及爆胎后车辆响应特性的变化,指出爆胎后车辆响应特性发生改变是导致驾驶员模型不能控制爆胎后汽车回到原路径的根本原因。建立了考虑爆胎后车辆左、右转向特性不对称的驾驶员模型,并进行了仿真。最后在原驾驶员模型中加入状态参考器,并对不同车速下的状态参考器参数进行辨识。解决了驾驶员模型在汽车爆胎仿真中的应用问题,为进一步研究汽车爆胎后驾驶员的操作规律及爆胎后汽车的稳定性控制提供了参考。     

步进电机式汽车仪表机芯的细分驱动

方案基于51单片机,通过驱动芯片ULN2003A,以软件模拟PWM的方法实现对步进电机式汽车仪表机芯的细分驱动,从而使步进电机式汽车仪表机芯的细分能在常见的51单片机上得以实现．方案详细介绍了电路的组成、工作原理及编程思想．     

家居物联实时终端设计与实现

物联网已成为当今各国重点科技发展战略。家居物联网因与人类生活密切相关,具有广阔的市场空间,在业界引起了广泛关注和积极研究。立足于实际家居物联网需求,特别考虑到实时性能和成本因素,设计了一套针对家居物联网的终端系统。该系统采用eCos(嵌入式可配置操作系统)作为嵌入式操作系统,开展了系统移植和驱动移植工作,利用eCos的实时功能设计来满足终端的实时性需求,以其开源性节约成本,为家居物联终端普及提供条件。此外结合家居物联网结构特点,通过在eCos系统上移植OLSR路由协议来实现家居网络的路由,增强网络的鲁棒性,为家居物联网的实时传输应用提供了良好支撑。总体看来,该家居物联终端具有优异的系统实时性和较高的经济适用性。     

基于VxWorks系统的二维硬件加速显示驱动技术

针对当前VxWorks系统图形显示驱动已无法满足用户需求的问题,提出了一种基于二维(2D)硬件加速引擎的图形显示驱动技术,实现了UGL的二维硬件加速、硬件光标、硬件双缓冲、Overlay覆盖等功能,提高了VxWorks系统的图形显示性能,满足了实时系统的应用需求.目前该设计已在多型海军装备中得到应用验证.