Drivers’ comprehension of traffic information on graphical route information panels

The concept of using signs to display graphical traffic information is now becoming increasingly popular. The main objective of this study was to design and undertake laboratory research to examine whether the content of traffic information displayed on graphical route information panel (GRIP) could be readily understood. Six kinds of GRIP signs that composed of three changeable information contents (road color only, road color with journey time, and road color with traffic speed) and two different road network types (triangle and tetragon) were proposed and tested in the experiment. Results showed that GRIP with road color only had the greatest optimum route choice percentage and the fastest response time compared to the other contents. On the contrary, GRIP with traffic speed had the slowest response time and the least optimum route choice percentage. Participants took less response time and greater optimum route choice percentage for triangle road network than for tetragon road network. Further, changeable information content interacted with road network type on response time and optimum route choice percentage. The road network type had little effect on response time and optimum route choice percentage under road color only, whereas under road color with journey time and road color with traffic speed, response times increased and optimum route choice percentage decreased significantly as road network complexity increased. Considering drivers’ comprehension and response, using road color only to present traffic condition on GRIP could be an applicable solution. Road color with traffic speed presented on GRIP was not recommended. Road color with journey time can be used for a simple road network. However, it was not suggested for a complex road network. The findings of this study could assist in displaying suitable traffic information on GRIP and in improving efficient driving for motorists.     

Can anti-speeding messages based on protection motivation theory influence reported speeding intentions?

The study investigated the effects of anti-speeding messages based on protection motivation theory (PMT) components: severity, vulnerability, rewards, self-efficacy, response efficacy, and response cost, on reported speeding intentions. Eighty-three participants aged 18–25 years holding a current Australian driver's license completed a questionnaire measuring their reported typical and recent speeding behaviors. Comparisons were made between 18 anti-speeding messages used on Australian roads and 18 new anti-speeding messages developed from the PMT model. Participants reported their reactions to the 36 messages on the perceived effectiveness of the message for themselves and for the general population of drivers, and also the likelihood of themselves and other drivers driving within the speed limit after viewing each message. Overall the PMT model-derived anti-speeding messages were better than jurisdiction-use anti-speeding messages in influencing participants’ reported intention to drive within the speed limit. Severity and vulnerability were the most effective PMT components for developing anti-speeding messages. Male participants reported significantly lower intention to drive within the speed limit than did female participants. However, males reported significantly higher intention to drive within the speed limit for PMT-derived messages compared with jurisdiction-based messages. Third-person effects were that males reported anti-speeding messages to be more effective for the general driving population than for themselves. Females reported the opposite effect – that all messages would be more effective for themselves than for the general driving population. Findings provided support for using a sound conceptual basis as an effective foundation for anti-speeding message development as well as for evaluating proposed anti-speeding messages on the target driver population.     

基于野外环境的便携式氢燃料电池创新设计研究

目的 探索野外环境下便携式氢燃料电池产品设计研究.方法 以便携性、实用性和安全性为依据展开研究,共设计8种色彩搭配及5种造型方案.邀请被试人员进行实验,通过眼动实验对数据进行分析,评估便携式氢燃料电池产品设计.其中,两根钢管贯穿机身方案的可拎取自由度高,符合军备用品造型定位,还能增强产品的牢固性,是实验中的最优选择.结论 色彩设计方面,稳重、隐蔽、越野的色彩元素是为最优;交互设计方面,易学、圆润为最适合的设计模式,其对提高操作效率与功能辨识度具有一定作用.     

数控设备显示器上的汉字文本阅读工效研究

目的研究影响电子显示器上汉字文本阅读工效的因素并提出建议。方法借鉴人机工程学经典理论,采用正交实验法,以数控机床显示器为对象、office word为载体,研究在显示器上进行单行和多行汉字阅读行为时字号、字距和行距对阅读工效的影响,并通过阅读速度、正确率和眼动指标来衡量阅读工效。结果在单行文本阅读中,最佳工效组合为字号12 pt、字间距2 pt;在多行文本阅读中,最佳工效组合为字号12 pt、字距2 pt、行距20 pt。结论研究得到的结果能为数控机床显示器、自助服务终端等类似机械设备上汉字格式的设置提供有效依据,让操作者能快速准确地理解和掌握文本信息,避免误操作。     

基于PCCS色彩体系和灰色关联分析的产品色彩设计方法

目的 旨在帮助设计人员把握产品色彩属性与用户意象感知间潜在联系,提高产品色彩设计效率。方法 采用多维统计及聚类分析获取PCCS色彩体系下的代表性色彩样本与语汇样本,并设置色彩语义量化实验获取色彩在各语汇尺度上的意象评值。以获取的评值量化数据为基础结合灰色关联分析,通过色彩转置在Lab均匀色彩空间中建立产品的色彩设计评价模型。结果 以双色儿童玩具车为对象进行产品色彩设计实践,构建的色彩设计评价模型良好达成了产品色彩方案的用色筛选、确认及评价优选等目标。结论 结合灰色关联分析,在PCCS色彩体系下构建的产品色彩设计评价模型能够有效提升产品方案的色彩设计效率,并对产品色彩方案的优选给出直观准确的参考标准。     

Prospect theory based estimation of drivers’ risk attitudes in route choice behaviors

This paper applied prospect theory (PT) to describe drivers’ route choice behavior under Variable Message Sign (VMS), which presented visual traffic information to assist them to make route choice decisions. A quite rich empirical data from questionnaire and field spot was used to estimate parameters of PT. In order to make the parameters more realistic with drivers’ attitudes, they were classified into different types by significant factors influencing their behaviors. Based on the travel time distribution of alternative routes and route choice results from questionnaire, the parameterized value function of each category was figured out, which represented drivers’ risk attitudes and choice characteristics. The empirical verification showed that the estimates were acceptable and effective. The result showed drivers’ risk attitudes and route choice characteristics could be captured by PT under real-time information shown on VMS. For practical application, once drivers’ route choice characteristics and parameters were identified, their route choice behavior under different road conditions could be predicted accurately, which was the basis of traffic guidance measures formulation and implementation for targeted traffic management. Moreover, the heterogeneous risk attitudes among drivers should be considered when releasing traffic information and regulating traffic flow.     

Tonpilz piezoelectric transducers with acoustic matching plates for underwater color image transmission

Tonpilz piezoelectric transducers with multiple acoustic matching plates are suitable for color image acoustic transmission, to achieve wideband low-ripple characteristics as well as high-efficiency high-power transmitting capability. The design method for the transducers was investigated on the basis of multiple-mode filter synthesis theory. For transducers with single, double, and triple matching plates, optimum specific acoustic impedances and lengths were calculated. Moreover, based on this design method, a 24 kHz array comprising nine identical transducers with single matching plates was built and evaluated. As a result, this array showed high-efficiency, low-ripple, and wideband characteristics. Excellent agreement between theoretical values and experimental results was obtained. A field test was carried out on color image transmission from a 3500 m sea depth, using the fabricated array, during which good color images were received.     

光信息存储量与真空技术

任何一种ＤＶＤ光盘都是由信息记录层、介质保护层、金属反射层．．．．．．等薄膜组成的二层、三层或多层光匹配的薄膜体系。不同膜系要用不同的真空淀积技术制备,各制备单元最终连成完整的光盘生产线。本文着重讨论各类光盘薄膜材料的真空淀积技术和相应的生产线,旨在探讨光盘生产线国产化的前景。     

Two-color medium-infrared scanning interferometer for the Frascati tokamak upgrade fusion test device

A scanning beam interferometer installed on the Frascati tokamak upgrade (FTU) experiment is presented. The scanning beam scheme combined with the small dimensions of the beams produces a system with very high spatial resolution: more than 30 adjacent (nonoverlapping) chords sample most of the plasma cross section. A good time resolution is achieved by the use of a proper scanning device, with a scanning frequency >or=8 kHz. Very fast events are measured by three additional fixed lines of sight providing a time resolution >or=100 kHz. The instrument is a two-color medium-infrared-compensated-type interferometer; two wavelengths (colors) are used to measure both the density and the mechanical vibrations of optical components. A CO2 laser (lambda=10.6 microm) is the main light source, and a CO laser (lambda=5.4 microm) is the compensation one. The optical scheme is a double pass Mach-Zehnder type. All the retroreflector mirrors are mounted directly on the FTU mechanical structure thanks to the compensation system that allows for large vibration amplitudes of optical components. Heterodyne detection at 30 and 40 MHz is obtained by frequency shifting the reference beams with two acousto-optic modulators (Bragg cells). Many features are implemented to achieve high measurement accuracy and reliability. A real-time system computes the integral density measured on one of the fixed lines of sight and provides an analog signal for density feedback control. The interferometer was used to measure density profiles both in medium-density discharges (n(e) approximately 10(20) m(-3)) and in high-density pellet injected discharges (n(e) approximately 7-8 x 10(20) m(-3)). The measurement error is approximately 2 x 10(18) m(-2) under optimal conditions but can be higher in some cases, mainly because of the large tilt of the retroreflector mirrors.     

The effect of family climate on risky driving of young novices: The moderating role of attitude and locus of control

The aim of the study was to examine the relative importance of young novice drivers’ family climate on their driving behavior. A sample of young novice drivers (N = 171) between the age of 17 and 24, who held their permanent (or temporary) driver's license for no longer than one year, participated. The questionnaire included items related to the participants’ family climate, 3 socio-cognitive determinants (i.e., attitude, locus of control and social norm), and risky driving behaviors. We expected both family climate and the socio-cognitive determinants to exert a direct effect on risky driving. Furthermore we hypothesized that the socio-cognitive determinants would moderate the impact of family climate on risky driving. The results showed that the effect of family climate on risky driving only originated from one single factor (i.e., noncommitment). Besides that, the results confirmed the importance of the three socio-cognitive determinants to the degree that attitude, locus of control, and social norm significantly predicted the self-reported risky driving. In line of what we hypothesized, attitude moderated the relationship between noncommitment and risky driving. Lastly, we found an unexpected three-way interaction which indicated that locus of control moderated the relation between noncommitment and risky driving only when young drivers’ attitude was risk-supportive. We recommend scholars and practitioners to take into account the interaction between external sources of influence (such as an individual's family climate) and more personally oriented dispositions (such as an individual's attitude, social norm and locus of control) when trying to explain and change young novices’ risky driving.     

Auditory detection and localization of approaching vehicles

Pedestrians must use a variety of cues when making safe decisions, many of which require processing of auditory information. We examined detection and localization of approaching vehicles using auditory cues. 50 adults ages 18–49 were presented with actual sounds of vehicles approaching at 5, 12, 25, and 35 mph. Three indices were of interest: the distance at which vehicles were detected, participants’ decision regarding the direction from which vehicles were approaching, and their determination of the vehicles’ arrival at their location. Participants more easily detected vehicles moving at higher speeds and vehicles approaching from the right. Determination of the direction of approach reached 90% accuracy or better when vehicles were traveling at, or greater than, 12 mph, and were more approaching from the right. Determination of vehicle arrival deteriorated significantly as speeds increased. Implications of the use of auditory cues in pedestrian settings, and future directions, are discussed.     

Driver perceptions of the safety implications of quiet electric vehicles

Previous research on the safety implications of quiet electric vehicles (EVs) has mostly focused on pedestrians’ acoustic perception of EVs, and suggests that EVs are more difficult for pedestrians to hear and, therefore, compromise traffic safety. The two German field studies presented here examine the experiences of 70 drivers with low noise emissions of EVs and the drivers’ long-term evaluation of the issue. Participants were surveyed via interviews and questionnaires before driving an EV for the first time, after 3 months of driving, and in the first study, again after 6 months. Based on participants’ reports, a catalogue of safety-relevant incidents was composed in Study 1. The catalogue revealed that low noise-related critical incidents only rarely occur, and mostly take place in low-speed environments. The degree of hazard related to these incidents was rated as low to medium. In Study 1, driver concern for vulnerable road users as a result of low noise diminished with increasing driving experience, while perceived comfort due to this feature increased. These results were replicated in Study 2. In the second study, it was additionally examined, if drivers adjust their perceived risk of harming other road users over time. Results show that the affective assessment of risk also decreased with increased driving experience. Based on individual experience, drivers adjust their evaluation of noise-related hazards, suggesting that dangers associated with low noise emissions might be less significant than previously expected.     

基于波束特征值分析的单双目标分辨技术方法

目标源数估计是基于特征值分析的高分辨谱估计技术中用来划分信号子空间和噪声子空间的关键步骤,现有的估计方法可以工作的最低信噪比大约在0dB左右。通过分析直线阵空间功率谱以及相关函数,给出了波束特征值的概念,并说明了波束特征值是由直线阵阵列流形所决定的,利用这一规律设计了波束特征值分辨波束内多目标的方法,可以在波束内分辨单、双目标,通过仿真分析说明可以在-10dB信噪比条件下工作。     

ESTIMATING SIMULATION METAMODELS USING COMBINED CORRELATION-BASED VARIANCE REDUCTION TECHNIQUES

This paper develops a procedure for jointly applying all of the correlation-based variance reduction techniques (namely, die methods of antithetic variates, common random numbers, and control variates) in a simulation experiment that is designed to estimate a linear metamodel (that is, a linear regression model) for a single response variable expressed in terms of an input vector of design variables for the target system. This procedure combines (a) the Schruben-Margolin strategy for metamodel estimation based on joint application of the methods of common random numbers and antithetic variates, and (b) a metamodel estimation scheme based on the method of control variates. Under specified conditions on the dependency structure of die simulation outputs and with respect to a variety of optimally criteria, the combined procedure is shown to be superior to each of the following conventional correlation-based variance reduction techniques: independent random number streams, common random number streams, control variates, and the original Schruben-Margolin strategy.     

Electro-elastic interaction between a piezoelectric screw dislocation and collinear rigid lines

Electro-elastic stress investigation on the interaction between a piezoelectric screw dislocation and collinear rigid lines under anti-plane mechanical and in-plane electrical loading is carried out. The lines are considered, respectively, as dielectrics or conductors. The screw dislocation is subjected to a line charge and a line force at the core. Closed-form analytical solutions are derived by means of complex variable method. Explicit expressions for the field variables, the singularity of the field variables at the line tip and the force on the dislocation are obtained for a single rigid line.     

The dimension-reduction strategy via mapping for probability density evolution analysis of nonlinear stochastic systems

Dynamic response analysis of nonlinear structures involving random parameters has for a long time been an important and challenging problem. In recent years, the probability density evolution method, which is capable of capturing the instantaneous probability density function (PDF) of the dynamic response and its evolution, has been proposed and developed for nonlinear stochastic dynamical systems. In the probability density evolution method, the strategy of selecting representative points is of critical importance to the efficiency especially when the number of random parameters is large. Enlightened by Cantor’s set theory, a strategy of dimension-reduction via mapping is proposed in the present paper. In the strategy, a two-dimensional domain is firstly considered and discretized such that the grid points are assigned with probabilities associated to the joint PDF. These points are then sorted and set on a virtual line according to a certain principle. Partitioning the sorted points on the virtual line into a certain number of intervals and selecting one single point in each interval, the two random variables can be transformed to a single comprehensive random variable. The associated probability of each point is simultaneously transformed accordingly. In the case of multiple random parameters, the above dimension-reduction procedure from two to one could be used recursively such that the random vector is finally transformed to one single comprehensive random variable. Numerical examples are investigated, showing that the proposed method is of high efficiency and fair accuracy.     

Effect of different breath alcohol concentrations on driving performance in horizontal curves

Driving under the influence of alcohol on curved roadway segments has a higher risk than driving on straight segments. To explore the effect of different breath alcohol concentration (BrAC) levels on driving performance in roadway curves, a driving simulation experiment was designed to collect 25 participants’ driving performance parameters (i.e., speed and lane position) under the influence of 4 BrAC levels (0.00%, 0.03%, 0.06% and 0.09%) on 6 types of roadway curves (3 radii × 2 turning directions). Driving performance data for 22 participants were collected successfully. Then the average and standard deviation of the two parameters were analyzed, considering the entire curve and different sections of the curve, respectively.     

一种可控激励的柔性基础-轴系推进实验系统

 为进行复杂海洋环境中因波浪载荷导致的船体柔性变形状态下的特种船舶-推进装置系统振动实验研究,提出了基于垫升船舶的激励可控的模拟实验系统的设计思想,设计了一种由柔性浮箱、弹性支承、变频电机、风机和空气螺旋桨负载、推进轴以及控制系统构成的船舶轴系推进装置的实验系统.为模拟波浪载荷对柔性船体变形的影响,研究了实验系统的激励控制元件、电路设计和激励控制策略.利用该实验系统,进行了10,20和30 mm等三种中拱变形状态下的基础变形控制测试.测试结果显示：该实验系统能对柔性基础的各弹性支承的高度进行组合调节,并具有良好的变形控制精度,能够模拟海洋环境激励对船体的影响.研究结果表明,该实验系统可为船体刚度较小的特种船舶进行推进装置振动特性研究提供有效的实验研究平台.     

ESR investigations on polyethylene-single wall carbon nanotube composites

Electron spin resonance investigations on single wall carbon nanotubes dispersed in polyethylene are reported. Three resonance lines were observed; a wide line assigned to magnetic iron clusters (catalyst residues), a broad and intense line originating from uncoupled electrons delocalized over the conducting domains of carbon nanotubes (in interaction with the electronic spins assigned to magnetic impurities), and a faint line superimposed on the broad one, assigned to paramagnetic impurities. The temperature dependence of resonance line parameters (resonance line position, width, and double integral) in the range 150–450 K has been analyzed. It was observed that the parameters of the broad and narrow lines are sensitive to the glass and melting relaxations occurring within the polymeric matrix.