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131.
驱动开发程序包(DDK)是TI公司提供的一套标准的DSP/BIOS驱动开发模型,基于此模型做视频驱动开发可简化驱动开发过程,增加代码的可移植性和兼容性。以TMS320DM642视频专用板为例,详述了视频驱动开发方法和开发过程,并以实例给出了调试结果。实践证明,基于TMS320DM642的DDK的视频驱动开发能为视频应用提供稳定的底层支持。 相似文献
132.
Over the last decade, driver distractions, such as cell phone use and texting, have become a significant contributor to roadway crashes. Some states now have legislation that severely restricts or bans driver activities deemed distracting. However, many policies and engineered countermeasures are based on self-reported crash data. This raises the issue of potential bias and when not controlled for in analysis supporting policy decisions, can lead to poor allocation of public resources. This study explores the impact of self-reporting driver distraction on the likelihood estimates of the injury severity category of vehicle crashes. Using a two-step correction technique, the presence of bias is tested, when present corrected, and its impact is interpreted. The findings show that self-reporting bias is present in the national database, a database often used to help evaluate policy and engineering options, self-reporting bias understates the true effect of driver distraction on injury severity, and it is not uniform across injury categories. As a result, the forecast of potential savings of countermeasure policies or in-vehicle devices will be distorted leading to inefficient allocation of public resources. 相似文献
133.
Abstract— By applying an energy‐recovery method to their driver circuits, the circuit power consumption of plasma displays can be reduced. However, further power reduction is necessary for large‐sized higher‐resolution displays such as used for Super HDTV. The ideal adiabatic charge method has been proven to be able to minimize circuit resistive element power consumption to 81 % of the conventional energy‐recovery‐circuit resistive‐element loss. An experimental pseudo‐adiabatic charge circuit that reduces the power consumption to about 90% of a conventional circuit has been demonstrated. The power consumption caused by both the resistance loss and the discharge loss of the switching‐element parasitic capacitances was analyzed. 相似文献
134.
分析了智能终端技术在矿用平台的可行性,并根据矿业生产的实际需求,提出了引进传统键盘输入技术作为输入系统的补充技术,替代无法在矿业环境使用的触摸屏技术,实现Android系统终端在矿业生产领域的引进,促进了以高速CPU、智能控制技术为代表的先进平台在矿业环境使用,逐步实现矿场设备的更新升级。 相似文献
135.
136.
Previous research on driver drowsiness detection has focused on developing in-car systems that continuously monitor the driver while driving and warn him/her when drowsiness compromises safety. In occupational settings a simple test of postural control has showed sensitivity to work shift induced fatigue in drivers. Whether the test is feasible for surveillance purposes in roadside settings is unknown. The present research sought to evaluate the feasibility of using a force platform test of postural control as a breathalyzer-like drowsiness-test at the roadside. 相似文献
137.
Since its publication, the Driver Behavior Questionnaire (DBQ) has been used for comparing subgroups of respondents on the constructs formed through factor analyzing the questionnaire items. However, not enough attention has been paid to ascertaining that the instrument actually measures the same constructs in the same way in all respondent groups. I recently published an article (Mattsson, 2012) that aimed to do this for the Finnish 28-item version of the DBQ using the stage-wise factorial invariance approach in the Exploratory Structural Equation Modeling (ESEM) context. de Winter (2013) commented on the publication, arguing that the results were artifacts due to measurement error that too many factors were extracted and that too strict criteria for invariance were applied. In this contribution, I reply to each criticism and suggest methodological approaches for ensuring the measurement invariance of self-report instruments such as the DBQ. 相似文献
138.
Personality traits are meaningful predictors of many significant life outcomes, including mortality. Several studies have investigated the relationship between specific personality traits and driving behaviours, e.g., aggression and speeding, in an attempt to identify traits associated with elevated crash risk. These studies, while valuable, are limited in that they examine only a narrow range of personality constructs and thus do not necessarily reveal which traits in constellation best predict aberrant driving behaviours. The primary aim of this study was to use a comprehensive measure of personality to investigate which personality traits are most predictive of four types of aberrant driving behaviour (Aggressive Violations, Ordinary Violations, Errors, Lapses) as indicated by the Manchester Driver Behaviour Questionnaire (DBQ). We recruited 285 young adults (67% female) from a university in the southeastern US. They completed self-report questionnaires including the DBQ and the Personality Inventory for DSM-5, which indexes 5 broad personality domains (Antagonism, Detachment, Disinhibition, Negative Affectivity, Psychoticism) and 25 specific trait facets. Confirmatory factor analysis showed adequate evidence for the DBQ internal structure. Structural regression analyses revealed that the personality domains of Antagonism and Negative Affectivity best predicted both Aggressive Violations and Ordinary Violations, whereas the best predictors of both Errors and Lapses were Negative Affectivity, Disinhibition and to a lesser extent Antagonism. A more nuanced analysis of trait facets revealed that Hostility was the best predictor of Aggressive Violations; Risk-taking and Hostility of Ordinary Violations; Irresponsibility, Separation Insecurity and Attention Seeking of Errors; and Perseveration and Irresponsibility of Lapses. 相似文献
139.
Introduction
Technical systems that warn or brake for vehicle–pedestrian encounters reduce injuries more effectively the earlier an intervention is initiated. However, premature intervention can irritate drivers, leading to system deactivation and, consequently, no injury reduction whatsoever. It has been proposed that no intervention should be initiated as long as attentive drivers are within their comfort zones. This study aims at quantifying driver comfort boundaries for pedestrian crossing situations to offer guidance for the appropriate timing of interventions.Methods
Sixty two volunteers drove through an intersection on a test track at 30 and 50 km/h. A pedestrian dummy was launched from behind an obstruction towards the driving path of the approaching car. Brake onset indicated discomfort. Time to collision (TTC), longitudinal and lateral distance were measured at brake onset.Results
TTC was independent of driving speed ranging from 2.1 to 4.3 s with a median of 3.2 s. Longitudinal distance ranged from 19 to 48 meters with an apparent difference between driving speeds. Lateral distances differed slightly, but significantly between driving speeds. The median was 3.1 m (3.2 m for 30 km/h and 2.9 m for 50 km/h) and values ranged from 1.9 to 4.1 m. Lateral distance in seconds ranged from 1.9 to 4.3 s with a median value of 3.1 s (3.2 s for 30 km/h and 3.0 s for 50 km/h).Discussion
TTC was independent of driving speed, trial order and volunteer age. It might be considered suitable to intervene in situations where, for example, 90% of drivers have exceeded their comfort boundary, i.e. when drivers have already initiated braking. This percentile value translates to intervention at a TTC of 2.5 s (95% confidence 2.4–2.7 s). The study was limited to Swedish nationals, fully aware drivers, and two driving speeds, but did not investigate behavioural changes due to system interaction.Conclusion
This study showed that TTC at brake onset was a suitable measure for the quantification of driver comfort boundaries in pedestrian crossing situations. All drivers applied their brakes prior to 2.1 s TTC. 相似文献140.
提出并设计了一种高精度、高效率LED照明驱动电路.采用平均电流控制模式代替峰值电流的控制模式;同时,采用低阶低侧的Buck拓扑结构,使输出驱动电流的精度误差控制在1%之内.整体电路的转换效率最高可达96%以上,输出驱动电流为350 mA,可驱动8个1W的HBLED灯.该设计基于CSMC 0.5μm 40 V BCD工艺,版图尺寸约为1.4 mm×1.4 mm.通过流片验证了设计的可行性. 相似文献