BEAM DYNAMICS STUDIES OF A HIGH-REPETITION RATE LINAC-DRIVER FOR A 4TH GENERATION LIGHT SOURCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ventturini, M.; Corlett, J.; Emma, P.

2012-05-18

We present recent progress toward the design of a super-conducting linac driver for a high-repetition rate FEL-based soft x-ray light source. The machine is designed to accept beams generated by the APEX photo-cathode gun operating with MHz-range repetition rate and deliver them to an array of SASE and seeded FEL beamlines. We review the current baseline design and report results of beam dynamics studies.

Design of laser diode driver with constant current and temperature control system

NASA Astrophysics Data System (ADS)

Wang, Ming-cai; Yang, Kai-yong; Wang, Zhi-guo; Fan, Zhen-fang

2017-10-01

A laser Diode (LD) driver with constant current and temperature control system is designed according to the LD working characteristics. We deeply researched the protection circuit and temperature control circuit based on thermos-electric cooler(TEC) cooling circuit and PID algorithm. The driver could realize constant current output and achieve stable temperature control of LD. Real-time feedback control method was adopted in the temperature control system to make LD work on its best temperature point. The output power variety and output wavelength shift of LD caused by current and temperature instability were decreased. Furthermore, the driving current and working temperature is adjustable according to specific requirements. The experiment result showed that the developed LD driver meets the characteristics of LD.

Speech-based E-mail and driver behavior: effects of an in-vehicle message system interface.

PubMed

Jamson, A Hamish; Westerman, Stephen J; Hockey, G Robert J; Carsten, Oliver M J

2004-01-01

As mobile office technology becomes more advanced, drivers have increased opportunity to process information "on the move." Although speech-based interfaces can minimize direct interference with driving, the cognitive demands associated with such systems may still cause distraction. We studied the effects on driving performance of an in-vehicle simulated "E-mail" message system; E-mails were either system controlled or driver controlled. A high-fidelity, fixed-base driving simulator was used to test 19 participants on a car-following task. Virtual traffic scenarios varying in driving demand. Drivers compensated for the secondary task by adopting longer headways but showed reduced anticipation of braking requirements and shorter time to collision. Drivers were also less reactive when processing E-mails, demonstrated by a reduction in steering wheel inputs. In most circumstances, there were advantages in providing drivers with control over when E-mails were opened. However, during periods without E-mail interaction in demanding traffic scenarios, drivers showed reduced braking anticipation. This may be a result of increased cognitive costs associated with the decision making process when using a driver-controlled interface when the task of scheduling E-mail acceptance is added to those of driving and E-mail response. Actual or potential applications of this research include the design of speech-based in-vehicle messaging systems.

High performance thyratron driver with low jitter.

PubMed

Verma, Rishi; Lee, P; Springham, S V; Tan, T L; Rawat, R S

2007-08-01

We report the design and development of insulated gate bipolar junction transistor based high performance driver for operating thyratrons in grounded grid mode. With careful design, the driver meets the specification of trigger output pulse rise time less than 30 ns, jitter less than +/-1 ns, and time delay less than 160 ns. It produces a -600 V pulse of 500 ns duration (full width at half maximum) at repetition rate ranging from 1 Hz to 1.14 kHz. The developed module also facilitates heating and biasing units along with protection circuitry in one complete package.

It Comes With the Job: Work Organizational, Job Design, and Self-Regulatory Barriers to Improving the Health Status of Train Drivers.

PubMed

Naweed, Anjum; Chapman, Janine; Allan, Matthew; Trigg, Joshua

2017-03-01

This study aimed to examine the impacts of key barriers to improving the occupational health status of Australian train drivers. From May to June, 2015, five semi-structured qualitative focus groups were conducted with 29 train drivers from South Australian, Victorian, and New South Wales-based rail organizations in Australia. Occupational health was impeded by multiple barriers regarding sleep (patterns/fatigue), diet (planning/context), mental health (occupational stress), rostering (low autonomy), sedentary time, low fitness motivation, and family/social life conflicts. Work organizational barriers included communication issues, low organizational support, and existing social norms. Job design barriers included rostering, fatigue, stimulant reliance, and family/social life imbalances. Self-regulatory barriers included dietary and exercise patterns habits and patterns. Occupational health interventions for Australian train drivers must address work organizational, job design, and self-regulatory barriers to healthier lifestyle behaviors.

Comprehending Consumption: The Behavioral Basis and Implementation of Driver Feedback for Reducing Vehicle Energy Use

NASA Astrophysics Data System (ADS)

Stillwater, Tai

A large body of evidence suggests that drivers who receive real-time fuel economy information can increase their vehicle fuel economy by 5%, a process commonly known as ecodriving. However, few studies have directly addressed the human side of the feedback, that is, why drivers would (or would not) be motivated to change their behavior and how to design feedback devices to maximize the motivation to ecodrive. This dissertation approaches the question using a mixed qualitative and quantitative approach to explore driver responses and psychology as well as to quantify the process of behavior change. The first chapter discusses the use of mile-per-gallon fuel economy as a metric for driver feedback and finds that an alternative energy economy metric is superior for real-time feedback. The second chapter reviews behavioral theories and proposes a number of practical solutions for the ecodriving context. In the third chapter the theory of planned behavior is tested against driver responses to an existing feedback system available in the 2008 model Toyota Prius. The fourth chapter presents a novel feedback design based on behavioral theories and drivers' responses to the feedback. Finally, chapter five presents the quantitative results of a natural-driving study of fuel economy feedback. The dissertation findings suggest that behavior theories such as the Theory of Planned Behavior can provide important improvements to existing feedback designs. In addition, a careful analysis of vehicle energy flows indicates that the mile-per-gallon metric is deeply flawed as a real-time feedback metric, and should be replaced. Chapters 2 and 3 conclude that behavior theories have both a theoretical and highly practical role in feedback design, although the driving context requires just as much care in the application. Chapters 4 and 5 find that a theory-inspired interface provides drivers with engaging and motivating feedback, and that integrating personal goal into the feedback is the most motivating theory-based addition. Finally, the behavioral model results in chapter 5 suggest that driver goals not only influence in-vehicle energy use, but are themselves flexible constructs that can be directly influenced by energy feedback.

Effect of changing driving conditions on driver behavior towards design of a safe and efficient traffic system.

DOT National Transportation Integrated Search

2013-12-01

This simulation-based study explores the effects of different work zone configurations, varying distances : between traffic signs, traffic density and individual differences on drivers behavior. Conventional Lane : Merge (CLM) and Joint Lane Merge...

Driver Vision Based Perception-Response Time Prediction and Assistance Model on Mountain Highway Curve.

PubMed

Li, Yi; Chen, Yuren

2016-12-30

To make driving assistance system more humanized, this study focused on the prediction and assistance of drivers' perception-response time on mountain highway curves. Field tests were conducted to collect real-time driving data and driver vision information. A driver-vision lane model quantified curve elements in drivers' vision. A multinomial log-linear model was established to predict perception-response time with traffic/road environment information, driver-vision lane model, and mechanical status (last second). A corresponding assistance model showed a positive impact on drivers' perception-response times on mountain highway curves. Model results revealed that the driver-vision lane model and visual elements did have important influence on drivers' perception-response time. Compared with roadside passive road safety infrastructure, proper visual geometry design, timely visual guidance, and visual information integrality of a curve are significant factors for drivers' perception-response time.

The effects of social interactions with in-vehicle agents on a driver's anger level, driving performance, situation awareness, and perceived workload.

PubMed

Jeon, Myounghoon; Walker, Bruce N; Gable, Thomas M

2015-09-01

Research has suggested that interaction with an in-vehicle software agent can improve a driver's psychological state and increase road safety. The present study explored the possibility of using an in-vehicle software agent to mitigate effects of driver anger on driving behavior. After either anger or neutral mood induction, 60 undergraduates drove in a simulator with two types of agent intervention. Results showed that both speech-based agents not only enhance driver situation awareness and driving performance, but also reduce their anger level and perceived workload. Regression models show that a driver's anger influences driving performance measures, mediated by situation awareness. The practical implications include design guidelines for the design of social interaction with in-vehicle software agents. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

The utility of the AusEd driving simulator in the clinical assessment of driver fatigue.

PubMed

Desai, Anup V; Wilsmore, Brad; Bartlett, Delwyn J; Unger, Gunnar; Constable, Ben; Joffe, David; Grunstein, Ronald R

2007-08-01

Several driving simulators have been developed which range in complexity from PC based driving tasks to advanced "real world" simulators. The AusEd driving simulator is a PC based task, which was designed to be conducive to and test for driver fatigue. This paper describes the AusEd driving simulator in detail, including the technical requirements, hardware, screen and file outputs, and analysis software. Some aspects of the test are standardized, while others can be modified to suit the experimental situation. The AusEd driving simulator is sensitive to performance decrement from driver fatigue in the laboratory setting, potentially making it useful as a laboratory or office based test for driver fatigue risk management. However, more research is still needed to correlate laboratory based simulator performance with real world driving performance and outcomes.

Exploring Challenges in Developing a Smart and Effective Assistive System for Improving the Experience of the Elderly Drivers

NASA Astrophysics Data System (ADS)

Jung, Sebin; Meng, Hong-Ying; Qin, Sheng-Feng

2017-09-01

As the overall population ages, driving-related accidents and injuries, associated with elderly drivers, have risen. Existing research about elderly drivers mainly focuses on factual data collection and analysis, indicating the elderly's growing fatal accident rates and their different behaviours compared to younger drivers. However, few research has focused on design-led practical solutions to mitigate the elderly's growing fatal accidents, by considering their usability and body conditions, afflicting the elderly, such as decreased vision, hearing, and reaction times. In this paper, first, current worldwide situations on growing fatal accident rates for elderly drivers is reviewed and the key impact factors are identified and discussed with regarding to usability and design trend in the automotive technology for elderly. Second, existing smart vehicle technology-based solutions to promote safe driving are explored and their pros and cons are discussed and analysed. Most of solutions are not created by people with driving difficulties, which are caused by health problems most commonly afflicting the elderly. Thirdly, diverse design-led research activities are taken, such as a survey, observation, and interviews to gain new understanding of what kinds of driving problems elderly drivers have and demonstrate how new system concepts could be developed for the elderly's benefits. Finally, it is found that the elderly's low vision and late reaction are main factors causing their driving difficulties. Based on this finding, usable vehicle system design ideas have been proposed, by utilising facial expression sensing technology as a solution. The proposed solutions would ensure reducing both the elderly's driving problems and high fatal accident rates and provide a more enjoyable driving environment for the elderly population.

Prediction of safe driving Behaviours based on health belief model: the case of taxi drivers in Bandar Abbas, Iran.

PubMed

Razmara, Asghar; Aghamolaei, Teamur; Madani, Abdoulhossain; Hosseini, Zahra; Zare, Shahram

2018-03-20

Road accidents are among the main causes of mortality. As safe and secure driving is a key strategy to reduce car injuries and offenses, the present research aimed to explore safe driving behaviours among taxi drivers based on the Health Belief Model (HBM). This study was conducted on 184 taxi drivers in Bandar Abbas who were selected based on a multiple stratified sampling method. Data were collected by a questionnaire comprised of a demographic information section along with the constructs of the HBM. Data were analysed by SPSS ver19 via a Pearson's correlation coefficient and multiple regressions. The mean age of the participants was 45.1 years (SD = 11.1). They all had, on average, 10.3 (SD = 7/5) years of taxi driving experience. Among the HBM components, cues to action and perceived benefits were shown to be positively correlated with safe driving behaviours, while perceived barriers were negatively correlated. Cues to action, perceived barriers and perceived benefits were shown to be the strongest predictors of a safe drivers' behaviour. Based on the results of this study in designing health promotion programmes to improve safe driving behaviours among taxi drivers, cues to action, perceived benefits and perceived barriers are important. Therefore, advertising, the design of information campaigns, emphasis on the benefits of safe driving behaviours and modification barriers are recommended.

Design of a Fatigue Detection System for High-Speed Trains Based on Driver Vigilance Using a Wireless Wearable EEG

PubMed Central

Zhang, Xiaoliang; Li, Jiali; Liu, Yugang; Zhang, Zutao; Wang, Zhuojun; Luo, Dianyuan; Zhou, Xiang; Zhu, Miankuan; Salman, Waleed; Hu, Guangdi; Wang, Chunbai

2017-01-01

The vigilance of the driver is important for railway safety, despite not being included in the safety management system (SMS) for high-speed train safety. In this paper, a novel fatigue detection system for high-speed train safety based on monitoring train driver vigilance using a wireless wearable electroencephalograph (EEG) is presented. This system is designed to detect whether the driver is drowsiness. The proposed system consists of three main parts: (1) a wireless wearable EEG collection; (2) train driver vigilance detection; and (3) early warning device for train driver. In the first part, an 8-channel wireless wearable brain-computer interface (BCI) device acquires the locomotive driver’s brain EEG signal comfortably under high-speed train-driving conditions. The recorded data are transmitted to a personal computer (PC) via Bluetooth. In the second step, a support vector machine (SVM) classification algorithm is implemented to determine the vigilance level using the Fast Fourier transform (FFT) to extract the EEG power spectrum density (PSD). In addition, an early warning device begins to work if fatigue is detected. The simulation and test results demonstrate the feasibility of the proposed fatigue detection system for high-speed train safety. PMID:28257073

Improving drivers' knowledge of road rules using digital games.

PubMed

Li, Qing; Tay, Richard

2014-04-01

Although a proficient knowledge of the road rules is important to safe driving, many drivers do not retain the knowledge acquired after they have obtained their licenses. Hence, more innovative and appealing methods are needed to improve drivers' knowledge of the road rules. This study examines the effect of game based learning on drivers' knowledge acquisition and retention. We find that playing an entertaining game that is designed to impart knowledge of the road rules not only improves players' knowledge but also helps them retain such knowledge. Hence, learning by gaming appears to be a promising learning approach for driver education. Copyright © 2013 Elsevier Ltd. All rights reserved.

Can we estimate plasma density in ICP driver through electrical parameters in RF circuit?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bandyopadhyay, M., E-mail: mainak@iter-india.org; Sudhir, Dass, E-mail: dass.sudhir@iter-india.org; Chakraborty, A., E-mail: arunkc@iter-india.org

2015-04-08

To avoid regular maintenance, invasive plasma diagnostics with probes are not included in the inductively coupled plasma (ICP) based ITER Neutral Beam (NB) source design. Even non-invasive probes like optical emission spectroscopic diagnostics are also not included in the present ITER NB design due to overall system design and interface issues. As a result, negative ion beam current through the extraction system in the ITER NB negative ion source is the only measurement which indicates plasma condition inside the ion source. However, beam current not only depends on the plasma condition near the extraction region but also on the perveancemore » condition of the ion extractor system and negative ion stripping. Nevertheless, inductively coupled plasma production region (RF driver region) is placed at distance (∼ 30cm) from the extraction region. Due to that, some uncertainties are expected to be involved if one tries to link beam current with plasma properties inside the RF driver. Plasma characterization in source RF driver region is utmost necessary to maintain the optimum condition for source operation. In this paper, a method of plasma density estimation is described, based on density dependent plasma load calculation.« less

DIRECT operational field test evaluation : natural use study : part 2 : driver satisfaction in DIRECT controlling for reliability

DOT National Transportation Integrated Search

1998-08-01

This report describes the DIRECT field test which was designed to evaluate the user benefits, institutional issues, and technical issues of en-route driver advisory and traveler information services. Focus was on testing and evaluating the voice-base...

CMOS output buffer wave shaper

NASA Technical Reports Server (NTRS)

Albertson, L.; Whitaker, S.; Merrell, R.

1990-01-01

As the switching speeds and densities of Digital CMOS integrated circuits continue to increase, output switching noise becomes more of a problem. A design technique which aids in the reduction of switching noise is reported. The output driver stage is analyzed through the use of an equivalent RLC circuit. The results of the analysis are used in the design of an output driver stage. A test circuit based on these techniques is being submitted to MOSIS for fabrication.

Driver-centred vehicle automation: using network analysis for agent-based modelling of the driver in highly automated driving systems.

PubMed

Banks, Victoria A; Stanton, Neville A

2016-11-01

To the average driver, the concept of automation in driving infers that they can become completely 'hands and feet free'. This is a common misconception, however, one that has been shown through the application of Network Analysis to new Cruise Assist technologies that may feature on our roads by 2020. Through the adoption of a Systems Theoretic approach, this paper introduces the concept of driver-initiated automation which reflects the role of the driver in highly automated driving systems. Using a combination of traditional task analysis and the application of quantitative network metrics, this agent-based modelling paper shows how the role of the driver remains an integral part of the driving system implicating the need for designers to ensure they are provided with the tools necessary to remain actively in-the-loop despite giving increasing opportunities to delegate their control to the automated subsystems. Practitioner Summary: This paper describes and analyses a driver-initiated command and control system of automation using representations afforded by task and social networks to understand how drivers remain actively involved in the task. A network analysis of different driver commands suggests that such a strategy does maintain the driver in the control loop.

Optical design of MOEMS-based micro-mechatronic modules for applications in spectroscopy

NASA Astrophysics Data System (ADS)

Tortschanoff, A.; Kremer, M.; Sandner, T.; Kenda, A.

2014-05-01

One of the important challenges for widespread application of MOEMS devices is to provide a modular interface for easy handling and accurate driving of the MOEMS elements, in order to enable seamless integration in larger spectroscopic system solutions. In this contribution we present in much detail the optical design of MOEMS driver modules comprising optical position sensing together with driver electronics, which can actively control different electrostatically driven MOEMS. Furthermore we will present concepts for compact spectroscopic devices, based on different MOEMS scanner modules with lD and 2D optical elements.

Detecting Driver Drowsiness Based on Sensors: A Review

PubMed Central

Sahayadhas, Arun; Sundaraj, Kenneth; Murugappan, Murugappan

2012-01-01

In recent years, driver drowsiness has been one of the major causes of road accidents and can lead to severe physical injuries, deaths and significant economic losses. Statistics indicate the need of a reliable driver drowsiness detection system which could alert the driver before a mishap happens. Researchers have attempted to determine driver drowsiness using the following measures: (1) vehicle-based measures; (2) behavioral measures and (3) physiological measures. A detailed review on these measures will provide insight on the present systems, issues associated with them and the enhancements that need to be done to make a robust system. In this paper, we review these three measures as to the sensors used and discuss the advantages and limitations of each. The various ways through which drowsiness has been experimentally manipulated is also discussed. We conclude that by designing a hybrid drowsiness detection system that combines non-intusive physiological measures with other measures one would accurately determine the drowsiness level of a driver. A number of road accidents might then be avoided if an alert is sent to a driver that is deemed drowsy. PMID:23223151

A simulator-based analysis of engineering treatments for right-hook bicycle crashes at signalized intersections.

PubMed

Warner, Jennifer; Hurwitz, David S; Monsere, Christopher M; Fleskes, Kayla

2017-07-01

A right-hook crash is a crash between a right-turning motor vehicle and an adjacent through-moving bicycle. At signalized intersections, these crashes can occur during any portion of the green interval when conflicting bicycles and vehicles are moving concurrently. The objective of this research was to evaluate the effectiveness of four types of engineering countermeasures - regulatory signage, intersection pavement marking, smaller curb radius, and protected intersection design - at modifying driver behaviors that are known contributing factors in these crashes. This research focused on right-hook crashes that occur during the latter stage of the circular green indication at signalized intersections with a shared right-turn and through lane. Changes in driver performance in response to treatments were measured in a high-fidelity driving simulator. Twenty-eight participants each completed 22 right-turn maneuvers. A partially counterbalanced experimental design exposed drivers to critical scenarios, which had been determined in a previous experiment. For each turn, driver performance measures, including visual attention, crash avoidance, and potential crash severity, were collected. A total of 75 incidents (47 near-collisions and 28 collisions) were observed during the 616 right turns. All treatments had some positive effect on measured driver performance with respect to the right-turn vehicle conflicts. Further work is required to map the magnitude of these changes in driver performance to crash-based outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Google glass: a driver distraction cause or cure?

PubMed

Sawyer, Ben D; Finomore, Victor S; Calvo, Andres A; Hancock, P A

2014-11-01

We assess the driving distraction potential of texting with Google Glass (Glass), a mobile wearable platform capable of receiving and sending short-message-service and other messaging formats. A known roadway danger, texting while driving has been targeted by legislation and widely banned. Supporters of Glass claim the head-mounted wearable computer is designed to deliver information without concurrent distraction. Existing literature supports the supposition that design decisions incorporated in Glass might facilitate messaging for drivers. We asked drivers in a simulator to drive and use either Glass or a smartphone-based messaging interface, then interrupted them with an emergency brake event. Both the response event and subsequent recovery were analyzed. Glass-delivered messages served to moderate but did not eliminate distracting cognitive demands. A potential passive cost to drivers merely wearing Glass was also observed. Messaging using either device impaired driving as compared to driving without multitasking. Glass in not a panacea as some supporters claim, but it does point the way to design interventions that effect reduced load in multitasking. Discussions of these identified benefits are framed within the potential of new in-vehicle systems that bring both novel forms of distraction and tools for mitigation into the driver's seat.

Risk management algorithm for rear-side collision avoidance using a combined steering torque overlay and differential braking

NASA Astrophysics Data System (ADS)

Lee, Junyung; Yi, Kyongsu; Yoo, Hyunjae; Chong, Hyokjin; Ko, Bongchul

2015-06-01

This paper describes a risk management algorithm for rear-side collision avoidance. The proposed risk management algorithm consists of a supervisor and a coordinator. The supervisor is designed to monitor collision risks between the subject vehicle and approaching vehicle in the adjacent lane. An appropriate criterion of intervention, which satisfies high acceptance to drivers through the consideration of a realistic traffic, has been determined based on the analysis of the kinematics of the vehicles in longitudinal and lateral directions. In order to assist the driver actively and increase driver's safety, a coordinator is designed to combine lateral control using a steering torque overlay by motor-driven power steering and differential braking by vehicle stability control. In order to prevent the collision while limiting actuator's control inputs and vehicle dynamics to safe values for the assurance of the driver's comfort, the Lyapunov theory and linear matrix inequalities based optimisation methods have been used. The proposed risk management algorithm has been evaluated via simulation using CarSim and MATLAB/Simulink.

Compact, Intelligent, Digitally Controlled IGBT Gate Drivers for a PEBB-Based ILC Marx Modulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, M.N.; Burkhart, C.; Olsen, J.J.

2010-06-07

SLAC National Accelerator Laboratory has built and is currently operating a first generation prototype Marx klystron modulator to meet ILC specifications. Under development is a second generation prototype, aimed at improving overall performance, serviceability, and manufacturability as compared to its predecessor. It is designed around 32 cells, each operating at 3.75 kV and correcting for its own capacitor droop. Due to the uniqueness of this application, high voltage gate drivers needed to be developed for the main 6.5 kV and droop correction 1.7 kV IGBTs. The gate driver provides vital functions such as protection of the IGBT from over-voltage andmore » over-current, detection of gate-emitter open and short circuit conditions, and monitoring of IGBT degradation (based on collector-emitter saturation voltage). Gate drive control, diagnostic processing capabilities, and communication are digitally implemented using an FPGA. This paper details the design of the gate driver circuitry, component selection, and construction layout. In addition, experimental results are included to illustrate the effectiveness of the protection circuit.« less

Safety reliability evaluation when vehicles turn right from urban major roads onto minor ones based on driver's visual perception.

PubMed

Yu, Bo; Chen, Yuren; Wang, Ruiyun; Dong, Yongjie

2016-10-01

Turning right has a significant impact on urban road traffic safety. Driving into the curve inappropriately or with improper turning speed often leads to a series of potential accidents and hidden dangers. For a long time, the design speed at intersections has been used to determine the physical radius of curbs and channelization, and drivers are expected to drive in accordance with the design speed. However, a large number of real vehicle tests show that for the road without an exclusive right-turn lane, there is not a good correlation between the physical radius of curbs and the turning right speeds. In this paper, shape parameters of the driver's visual lane model are put forward and they have relatively high correlations with right-turn speeds. Hence, an evaluation method about safety reliability of turning right from urban major roads onto minor ones based on driver's visual perception is proposed. For existing roads, the evaluation object could be real driving videos; for those under construction roads, the evaluation object could be visual scenes obtained from a driving simulation device. Findings in this research will make a contribution to the optimization of right-turn design at intersections and lead to the development of auxiliary driving technology. Copyright © 2015 Elsevier Ltd. All rights reserved.

Design of a quasi-CW laser diode driver for space-based laser transmitter

NASA Astrophysics Data System (ADS)

Singh, Ravindra; Dangwal, Nishma; Chandraprakash, .; Agrawal, Lalita; Pal, Suranjan; Kamlakar, J. A.

2006-12-01

LASTEC Delhi in a joint collaborative activity with LEOS, Bangalore is developing a space qualified diode array pumped Nd:YAG laser transmitter delivering 30 mJ @ 10 pps of 10 ns duration. For space applications laser diodes are preferred because of their excellent reliability with lifetimes exceeding 100,000 hours. However, they are extremely sensitive to electro-static discharge, excessive current levels, and current spikes and transients. Small variations in bias voltage may produce large fluctuations in the current causing instability and damage to the device. Hence instead of the traditional power supplies a current controlled laser diode driver is required. This paper presents the design of a Q-CW laser diode driver based on closed loop current regulator, capable of driving 24 QCW laser diode bars each with 75W peak power at 70 A. The driver can generate up to 100 Amp peak current and 200μsec pulse width operating at 10 Hz. The current source design includes special circuits for low noise operation, slow turn-on and turn-off, circuits for over voltage and transient current protection; and good regulation. Space qualified and radiation hardened components are required to be used to sustain stringent space environment requirements during mission life of two years.

On the feasibility of a fiber-based inertial fusion laser driver

NASA Astrophysics Data System (ADS)

Labaune, C.; Hulin, D.; Galvanauskas, A.; Mourou, G. A.

2008-08-01

One critical issue for the realization of Inertial Fusion Energy (IFE) power plants is the driver efficiency. High driver efficiency will greatly relax the driver energy requested to produce a fusion gain, resulting in more compact and less costly facilities. Among lasers, systems based on guided wave such as diode pumped Yb:glass fiber-amplifiers with a demonstrated overall efficiency close to 70% as opposed to few percents for systems based on free propagation, offer some intriguing opportunities. Guided optics provides the enormous advantage to directly benefit from the telecommunication industry where components are made cheap, rugged, well tested, environmentally stable, with lifetimes measured in tens of years and compatible with massive manufacturing. In this paper, we are studying the possibility to design a laser driver solely based on guided wave optics. We call this concept FAN for Fiber Amplification Network. It represents a profound departure from already proposed laser drivers all based on free propagation optics. The system will use a large number of identical fibers to combines long (ns) and short (ps) pulses that are needed for the fast ignition scheme. Technical details are discussed relative to fiber type, pump, phasing, pulse shaping and timing as well as fiber distribution around the chamber. The proposed fiber driver provides maximum and independent control on the wavefront, pulse duration, pulse shape, timing, making possible reaching the highest gain. The massive manufacturing will be amenable to a cheaper facility with an easy upkeep.

Negotiating a Systems Development Method

NASA Astrophysics Data System (ADS)

Karlsson, Fredrik; Hedström, Karin

Systems development methods (or methods) are often applied in tailored version to fit the actual situation. Method tailoring is in most the existing literature viewed as either (a) a highly rational process with the method engineer as the driver where the project members are passive information providers or (b) an unstructured process where the systems developer makes individual choices, a selection process without any driver. The purpose of this chapter is to illustrate that important design decisions during method tailoring are made by project members through negotiation. The study has been carried out using the perspective of actor-network theory. Our narratives depict method tailoring as more complex than (a) and (b) show the driver role rotates between the project members, and design decisions are based on influences from several project members. However, these design decisions are not consensus decisions.

Gigascale Silicon Photonic Transmitters Integrating HBT-based Carrier-injection Electroabsorption Modulator Structures

NASA Astrophysics Data System (ADS)

Fu, Enjin

Demand for more bandwidth is rapidly increasing, which is driven by data intensive applications such as high-definition (HD) video streaming, cloud storage, and terascale computing applications. Next-generation high-performance computing systems require power efficient chip-to-chip and intra-chip interconnect yielding densities on the order of 1Tbps/cm2. The performance requirements of such system are the driving force behind the development of silicon integrated optical interconnect, providing a cost-effective solution for fully integrated optical interconnect systems on a single substrate. Compared to conventional electrical interconnect, optical interconnects have several advantages, including frequency independent insertion loss resulting in ultra wide bandwidth and link latency reduction. For high-speed optical transmitter modules, the optical modulator is a key component of the optical I/O channel. This thesis presents a silicon integrated optical transmitter module design based on a novel silicon HBT-based carrier injection electroabsorption modulator (EAM), which has the merits of wide optical bandwidth, high speed, low power, low drive voltage, small footprint, and high modulation efficiency. The structure, mechanism, and fabrication of the modulator structure will be discussed which is followed by the electrical modeling of the post-processed modulator device. The design and realization of a 10Gbps monolithic optical transmitter module integrating the driver circuit architecture and the HBT-based EAM device in a 130nm BiCMOS process is discussed. For high power efficiency, a 6Gbps ultra-low power driver IC implemented in a 130nm BiCMOS process is presented. The driver IC incorporates an integrated 27-1 pseudo-random bit sequence (PRBS) generator for reliable high-speed testing, and a driver circuit featuring digitally-tuned pre-emphasis signal strength. With outstanding drive capability, the driver module can be applied to a wide range of carrier injection modulators and light-emitting diodes (LED) with drive voltage requirements below 1.5V. Measurement results show an optical link based on a 70MHz red LED work well at 300Mbps by using the pre-emphasis driver module. A traveling wave electrode (TWE) modulator structure is presented, including a novel design methodology to address process limitations imposed by a commercial silicon fabrication technology. Results from 3D full wave EM simulation demonstrate the application of the design methodology to achieve specifications, including phase velocity matching, insertion loss, and impedance matching. Results show the HBT-based TWE-EAM system has the bandwidth higher than 60GHz.

Are drivers with CVD more at risk for motor vehicle crashes? Study of men aged 45 to 70.

PubMed Central

Guibert, R.; Potvin, L.; Ciampi, A.; Loiselle, J.; Philibert, L.; Franco, E. D.

1998-01-01

OBJECTIVE: To examine whether male drivers aged 45 to 70 years suffering from cardiovascular disease (CVD) are more likely to be involved in motor vehicle crashes (MVC) that are reported to the police. DESIGN: Population-based case-control study. SETTING: Data on drivers' ages and medical conditions were compiled from the Societé de l'assurance automobile du Québec's (SAAQ) computerized files. A questionnaire was mailed to all subjects to collect additional information on annual distances driven and various driving behaviours. PARTICIPANTS: Age-stratified population-based random sample. Subjects were 2504 drivers involved in MVCs during a 6-month period; controls were 2520 drivers not involved in crashes. MAIN OUTCOME MEASURES: Proportion of drivers with CVD involved in MVCs. RESULTS: Response rate to the questionnaire was 35.5%. Analysis of the SAAQ files' entire sample of 5024 drivers showed that drivers suffering from CVD were less likely to be involved in MVCs (odds ratio [OR] 0.82, 95% confidence interval [CI] 0.67 to 0.99) than drivers without CVD. Although the estimate of risk remains unchanged when adjusted for age, it becomes statistically insignificant. It also remains unchanged and statistically insignificant when adjusted for yearly distance driven and driver behaviour, as shown by responses to the questionnaire. Drivers suffering from CVD drove significantly less each year (8900 km) than drivers without medical conditions (13,000 km). CONCLUSION: This study shows no increased risk of motor vehicle crashes for drivers suffering from CVD. PMID:9585850

Simulation-based evaluation of an in-vehicle smart situation awareness enhancement system.

PubMed

Gregoriades, Andreas; Sutcliffe, Alistair

2018-07-01

Situation awareness (SA) constitutes a critical factor in road safety, strongly related to accidents. This paper describes the evaluation of a proposed SA enhancement system (SAES) that exploits augmented reality through a head-up display (HUD). Two SAES designs were evaluation (information rich vs. minimal information) using a custom-made simulator and the Situation Awareness Global Assessment Technique with performance and EEG measures. The paper describes the process of assessing the SA of drivers using the SAES, through a series of experiments with participants in a Cave Automatic Virtual Environment. The effectiveness of the SAES was tested in a within-group research design. The results showed that the information rich (radar-style display) was superior to the minimal (arrow hazard indicator) design and that both SAES improved drivers' SA and performance compared to the control (no HUD) design. Practitioner Summary: Even though driver situation awareness is considered as one of the leading causes of road accidents, little has been done to enhance it. The current study demonstrates the positive effect of a proposed situation awareness enhancement system on driver situation awareness, through an experiment using virtual prototyping in a simulator.

Integrated control design for driver assistance systems based on LPV methods

NASA Astrophysics Data System (ADS)

Gáspár, Péter; Németh, Balázs

2016-12-01

The paper proposes a control design method for a driver assistance system. In the operation of the system, a predefined trajectory required by the driver with a steering command is followed. During manoeuvres the control system generates differential brake moment and the auxiliary front-wheel steering angle and changes the camber angles of the wheels in order to improve the tracking of the road trajectory. The performance specifications are guaranteed by the local controllers, i.e. the brake, the steering, and the suspension systems, while the coordination of these components is provided by the supervisor. The advantage of this architecture is that local controllers are designed independently, which is ensured by the fact that the monitoring signals are taken into consideration in the formalisation of their performance specifications. The fault-tolerant control can be achieved by incorporating the detected fault signals in their performance specifications. The control system also uses a driver model, with which the reference signal can be generated. In the control design, the parameter-dependent linear parameter-varyingmethod, which meets the performance specifications, is used. The operation of the control system is illustrated through different normal and emergency vehicle manoeuvres with a high-accuracy simulation software.

A Smartphone-Based Driver Safety Monitoring System Using Data Fusion

PubMed Central

Lee, Boon-Giin; Chung, Wan-Young

2012-01-01

This paper proposes a method for monitoring driver safety levels using a data fusion approach based on several discrete data types: eye features, bio-signal variation, in-vehicle temperature, and vehicle speed. The driver safety monitoring system was developed in practice in the form of an application for an Android-based smartphone device, where measuring safety-related data requires no extra monetary expenditure or equipment. Moreover, the system provides high resolution and flexibility. The safety monitoring process involves the fusion of attributes gathered from different sensors, including video, electrocardiography, photoplethysmography, temperature, and a three-axis accelerometer, that are assigned as input variables to an inference analysis framework. A Fuzzy Bayesian framework is designed to indicate the driver’s capability level and is updated continuously in real-time. The sensory data are transmitted via Bluetooth communication to the smartphone device. A fake incoming call warning service alerts the driver if his or her safety level is suspiciously compromised. Realistic testing of the system demonstrates the practical benefits of multiple features and their fusion in providing a more authentic and effective driver safety monitoring. PMID:23247416

Toward best practice in Human Machine Interface design for older drivers: A review of current design guidelines.

PubMed

Young, K L; Koppel, S; Charlton, J L

2017-09-01

Older adults are the fastest growing segment of the driving population. While there is a strong emphasis for older people to maintain their mobility, the safety of older drivers is a serious community concern. Frailty and declines in a range of age-related sensory, cognitive, and physical impairments can place older drivers at an increased risk of crash-related injuries and death. A number of studies have indicated that in-vehicle technologies such as Advanced Driver Assistance Systems (ADAS) and In-Vehicle Information Systems (IVIS) may provide assistance to older drivers. However, these technologies will only benefit older drivers if their design is congruent with the complex needs and diverse abilities of this driving cohort. The design of ADAS and IVIS is largely informed by automotive Human Machine Interface (HMI) guidelines. However, it is unclear to what extent the declining sensory, cognitive and physical capabilities of older drivers are addressed in the current guidelines. This paper provides a review of key current design guidelines for IVIS and ADAS with respect to the extent they address age-related changes in functional capacities. The review revealed that most of the HMI guidelines do not address design issues related to older driver impairments. In fact, in many guidelines driver age and sensory cognitive and physical impairments are not mentioned at all and where reference is made, it is typically very broad. Prescriptive advice on how to actually design a system so that it addresses the needs and limitations of older drivers is not provided. In order for older drivers to reap the full benefits that in-vehicle technology can afford, it is critical that further work establish how older driver limitations and capabilities can be supported by the system design process, including their inclusion into HMI design guidelines. Copyright © 2016 Elsevier Ltd. All rights reserved.

A wide bandgap silicon carbide (SiC) gate driver for high-temperature and high-voltage applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lamichhane, Ranjan; Ericson, Milton Nance; Frank, Steven Shane

2014-01-01

Limitations of silicon (Si) based power electronic devices can be overcome with Silicon Carbide (SiC) because of its remarkable material properties. SiC is a wide bandgap semiconductor material with larger bandgap, lower leakage currents, higher breakdown electric field, and higher thermal conductivity, which promotes higher switching frequencies for high power applications, higher temperature operation, and results in higher power density devices relative to Si [1]. The proposed work is focused on design of a SiC gate driver to drive a SiC power MOSFET, on a Cree SiC process, with rise/fall times (less than 100 ns) suitable for 500 kHz tomore » 1 MHz switching frequency applications. A process optimized gate driver topology design which is significantly different from generic Si circuit design is proposed. The ultimate goal of the project is to integrate this gate driver into a Toyota Prius plug-in hybrid electric vehicle (PHEV) charger module. The application of this high frequency charger will result in lighter, smaller, cheaper, and a more efficient power electronics system.« less

Pay as You Speed, ISA with incentives for not speeding: a case of test driver recruitment.

PubMed

Lahrmann, Harry; Agerholm, Niels; Tradisauskas, Nerius; Næss, Teresa; Juhl, Jens; Harms, Lisbeth

2012-09-01

The Intelligent Speed Adaptation (ISA) project we describe in this article is based on Pay as You Drive principles. These principles assume that the ISA equipment informs a driver of the speed limit, warns the driver when speeding and calculates penalty points. Each penalty point entails the reduction of a 30% discount on the driver's car insurance premium, which therefore produced the name, Pay as You Speed. The ISA equipment consists of a GPS-based On Board Unit with a mobile phone connection to a web server. The project was planned for a three-year test period with 300 young car drivers, but it never succeeded in recruiting that number of drivers. After several design changes, the project eventually went forward with 153 test drivers of all ages. This number represents approximately one thousandth of all car owners in the proving ground of North Jutland in Denmark. Furthermore the project was terminated before its scheduled closing date. This article describes the project with an emphasis on recruitment efforts and the project's progress. We include a discussion of possible explanations for the failure to recruit volunteers for the project and reflect upon the general barriers to using ISA with ordinary drivers. Copyright © 2011 Elsevier Ltd. All rights reserved.

U.S. truck driver anthropometric study and multivariate anthropometric models for cab designs.

PubMed

Guan, Jinhua; Hsiao, Hongwei; Bradtmiller, Bruce; Kau, Tsui-Ying; Reed, Matthew R; Jahns, Steven K; Loczi, Josef; Hardee, H Lenora; Piamonte, Dominic Paul T

2012-10-01

This study presents data from a large-scale anthropometric study of U.S. truck drivers and the multivariate anthropometric models developed for the design of next-generation truck cabs. Up-to-date anthropometric information of the U.S. truck driver population is needed for the design of safe and ergonomically efficient truck cabs. We collected 35 anthropometric dimensions for 1,950 truck drivers (1,779 males and 171 females) across the continental United States using a sampling plan designed to capture the appropriate ethnic, gender, and age distributions of the truck driver population. Truck drivers are heavier than the U.S.general population, with a difference in mean body weight of 13.5 kg for males and 15.4 kg for females. They are also different in physique from the U.S. general population. In addition, the current truck drivers are heavier and different in physique compared to their counterparts of 25 to 30 years ago. The data obtained in this study provide more accurate anthropometric information for cab designs than do the current U.S. general population data or truck driver data collected 25 to 30 years ago. Multivariate anthropometric models, spanning 95% of the current truck driver population on the basis of a set of 12 anthropometric measurements, have been developed to facilitate future cab designs. The up-to-date truck driver anthropometric data and multivariate anthropometric models will benefit the design of future truck cabs which, in turn, will help promote the safety and health of the U.S. truck drivers.

The overall program effects of California's 3-Tier Assessment System pilot on crashes and mobility among senior drivers.

PubMed

Camp, Bayliss J

2013-12-01

In 2007, the California Department of Motor Vehicles (DMV) undertook a pilot study of the 3-Tier Assessment System, the purpose of which was to examine, in a large-scale real-time public agency setting, the effectiveness of this method for both reducing the crash risk of individual drivers and for extending the safe driving years of Californian drivers of all ages. The 3-Tier Assessment System consisted of tiered series of screening tools incorporated into the in-office driver's license renewal process. These screening tools identified drivers with various kinds of functional limitations (physical, visual, and cognitive/perceptual), that might impact safe driving. Paired with the screening tools were educational materials designed to improve drivers' knowledge of their own limitations, including compensating techniques. The present study is a population-based evaluation of the effects of the pilot on subsequent crash risk and mobility outcomes (including delicensure) of participating drivers age 70 and older. Pilot participants were compared with two control groups processed according to standard California DMV license renewal procedures. Because the 3-Tier Assessment System was designed to identify limitations normally associated with aging, the present analyses focus on drivers age 70 and older. However, it should be emphasized that during the 3-Tier pilot the screening tools were applied to drivers of all ages. There were two main findings. First, there were no consistent, statistically significant differences between the pilot and control groups in crash risk in the two years following screening. Second, pilot participants experienced statistically significant effects on mobility. These effects included delays in time to complete their license renewal, an increase in the number of assigned license restrictions, and an increase in the number of customers failing to renew their driving privilege. Based on these findings, suggestions for further research are made. None. © 2013.

Use patterns among early adopters of adaptive cruise control.

PubMed

Xiong, Huimin; Boyle, Linda Ng; Moeckli, Jane; Dow, Benjamin R; Brown, Timothy L

2012-10-01

The objective of this study was to investigate use patterns among early adopters of adaptive cruise control (ACC). Extended use ofACC may influence a driver's behavior in the long-term, which can have unintended safety consequences. The authors examined the use of a motion-based simulator by 24 participants (15 males and 9 females). Cluster analysis was performed on drivers' use of ACC and was based on their gap settings, speed settings, number of warnings issued, and ACC disengaged. The data were then examined on the basis of driving performance measures and drivers' subjective responses to trust in ACC, understanding of system operations, and driving styles. Driving performance measures included minimum time headway, adjusted minimum time to collision, and drivers' reaction time to critical events. Three groups of drivers were observed on the basis of risky behavior, moderately risky behavior, and conservative behavior. Drivers in the conservative group stayed farther behind the lead vehicle than did drivers in the other two groups. Risky drivers responded later to critical events and had more ACC warnings issued. Safety consequences with ACC may be more prevalent in some driver groups than others. The findings suggest that these safety implications are related to trust in automation, driving styles, understanding of system operations, and personalities. Potential applications of this research include enhanced design for next-generation ACC systems and countermeasures to improve safe driving with ACC.

Quantifying driver's field-of-view in tractors: methodology and case study.

PubMed

Gilad, Issachar; Byran, Eyal

2015-01-01

When driving a car, the visual awareness is important for operating and controlling the vehicle. When operating a tractor, it is even more complex. This is because the driving is always accompanied with another task (e.g., plough) that demands constant changes of body postures, to achieve the needed Field-of-View (FoV). Therefore, the cockpit must be well designed to provide best FoV. Today, the driver's FoV is analyzed mostly by computer simulations of a cockpit model and a Digital Human Model (DHM) positioned inside. The outcome is an 'Eye view' that displays what the DHM 'sees'. This paper suggests a new approach that adds quantitative information to the current display; presented on three tractor models as case studies. Based on the results, the design can be modified. This may assist the engineer, to analyze, compare and improve the design, for better addressing the driver needs.

The strength of graduated drivers license programs and fatalities among teen drivers and passengers.

PubMed

Morrisey, Michael A; Grabowski, David C; Dee, Thomas S; Campbell, Christine

2006-01-01

The purpose of this study is to investigate the effects of differentially stringent graduated drivers license programs on teen driver fatalities, day-time and night-time teen driver fatalities, fatalities of teen drivers with passengers present, and fatalities among teen passengers. The study uses 1992-2002 data on motor vehicle fatalities among 15-17-year-old drivers from the Fatality Analysis Reporting System to identify the effects of "good", "fair", and "marginal" GDL programs based upon designations by the Insurance Institute for Highway Safety. Analysis is conducted using conditional negative binomial regressions with fixed effects. "Good" programs reduce total fatalities among young drivers by 19.4% (c.i. -33.0%, -5.9%). "Fair" programs reduce night-time young driver fatalities by 12.6% (c.i. -23.9%, -1.2%), but have no effect on day-time fatalities. "Marginal" programs had no statistically meaningful effect on driver fatalities. All three types of programs reduced teen passenger fatalities, but the effects of limitations on the number of passengers appear to have had only minimal effects in reducing fatalities among young drivers themselves. Stronger GDL programs are more effective than weaker programs in reducing teenage motor vehicle fatalities.

Informational Report on Lighting Design for Midblock Crosswalks

DOT National Transportation Integrated Search

2008-04-01

This report provides information on lighting parameters and design criteria that should be considered when installing fixed roadway lighting for midblock crosswalks. The information is based on static and dynamic experiments of driver performance wit...

Speech-based interaction with in-vehicle computers: the effect of speech-based e-mail on drivers' attention to the roadway.

PubMed

Lee, J D; Caven, B; Haake, S; Brown, T L

2001-01-01

As computer applications for cars emerge, a speech-based interface offers an appealing alternative to the visually demanding direct manipulation interface. However, speech-based systems may pose cognitive demands that could undermine driving safety. This study used a car-following task to evaluate how a speech-based e-mail system affects drivers' response to the periodic braking of a lead vehicle. The study included 24 drivers between the ages of 18 and 24 years. A baseline condition with no e-mail system was compared with a simple and a complex e-mail system in both simple and complex driving environments. The results show a 30% (310 ms) increase in reaction time when the speech-based system is used. Subjective workload ratings and probe questions also indicate that speech-based interaction introduces a significant cognitive load, which was highest for the complex e-mail system. These data show that a speech-based interface is not a panacea that eliminates the potential distraction of in-vehicle computers. Actual or potential applications of this research include design of in-vehicle information systems and evaluation of their contributions to driver distraction.

Relationships of working conditions, health problems and vehicle accidents in bus rapid transit (BRT) drivers.

PubMed

Gómez-Ortiz, Viviola; Cendales, Boris; Useche, Sergio; Bocarejo, Juan P

2018-04-01

The aim of this study was to estimate accident risk rates and mental health of bus rapid transit (BRT) drivers based on psychosocial risk factors at work leading to increased stress and health problems. A cross-sectional research design utilized a self-report questionnaire completed by 524 BRT drivers. Some working conditions of BRT drivers (lack of social support from supervisors and perceived potential for risk) may partially explain Bogota's BRT drivers' involvement in road accidents. Drivers' mental health problems were associated with higher job strain, less support from co-workers, fewer rewards and greater signal conflict while driving. To prevent bus accidents, supervisory support may need to be increased. To prevent mental health problems, other interventions may be needed such as reducing demands, increasing job control, reducing amount of incoming information, simplifying current signals, making signals less contradictory, and revising rewards. © 2018 Wiley Periodicals, Inc.

Drivers within natural drinking groups: an exploration of role selection, motivation, and group influence on driver sobriety.

PubMed

Lange, James E; Johnson, Mark B; Reed, Mark B

2006-01-01

Young people consume alcohol almost exclusively in social contexts, but natural drinking group dynamics are poorly understood. Our research focuses on the drivers' role within natural drinking groups. We conducted breath-test surveys of existing groups of young people at the US/Mexico border crossing before they headed to Tijuana bars, and surveyed them again upon their return. Results indicated an individual's perception of other group member's drinking plans predicts drinking intentions to a greater degree for passengers than drivers. Additionally, drivers who anticipated heavy drinking among other group members returned to the United States with BACs nearly identical to drivers who reported that other group members would not drink at all. This suggests drivers were resistant to normative pressures to drink. Evidence that group-dynamic variables may impact drinking behavior underscores the importance of systematic exploration of natural drinking groups. Furthermore, the knowledge gleaned from studying the dynamics and decision making processes of natural drinking groups could be used to design intervention designed to increase designated driver use and to reduce drinking among designated drivers.

Attitudes of Greek Drivers with Focus on Mobile Phone Use While Driving.

PubMed

Yannis, George; Theofilatos, Athanasios; Marinou, Paraskevi

2015-01-01

This article investigates the attitudes and behavior of Greek drivers with specific focus on mobile phone use while driving. The research is based on the data of the pan-European SARTRE 4 survey, which was conducted on a representative sample of Greek drivers in 2011. Analysis of the drivers' behavior was carried out by the statistical methods of factor and cluster analysis. According to the results of factor analysis, Greek drivers' responses in the selected questions were summarized into 4 factors, describing road behavior and accident involvement probability as well as their views on issues concerning other drivers' road behaviors, fatigued driving, enforcement of road safety, and mobile phone use while driving. The results of cluster analysis indicated 5 different groups of Greek drivers--the moderate, the optimistic, the conservative, the risky, and the reasonably cautious--and the characteristics of each group where identified. These results may be useful for the appropriate design of targeted road safety campaigns and other countermeasures.

The prevalence of and factors associated with tobacco smoking behavior among long-distance drivers in Lagos, Nigeria.

PubMed

Ozoh, Obianuju B; Akanbi, Maxwell O; Amadi, Casmir E; Vollmer, William; Bruce, Nigel

2017-09-01

Factors associated with tobacco smoking are useful in designing tobacco control programs. To estimate the prevalence of and factors associated with tobacco smoking among long-distance drivers. This was a cross-sectional study. Stratified cluster sampling approach was used to select drivers based on if they received annual health screening (AHS) or not (non AHS). We used a structured questionnaire to obtain information and weighted the resulting observations to derive population based estimates. Association between tobacco smoking and socio-demographic factors was explored in multivariate models. 414 male drivers, mean age 43.6 (standard error 0.6) years. Population weighted prevalence of current smoking was 18.9% (95% CI: 14.3-23.4) of all drivers, 6.5% (95% CI: 2.6-10.4) of AHS drivers and 19.5 (95% CI: 14.7-24.2) of non AHS drivers (p<0.001). In multivariate models, having close friends that smoked (OR= 6.36, 95% CI= 2.49 - 16.20) cargo driving (OR= 2.58, 95% CI= 1.29 - 5.15) and lower education levels (OR for post-secondary education vs. primary education or less= 0.17, 95% CI= 0.04 - 0.81) were associated with current smoking. Prevalence of tobacco smoking is higher among non AHS compared to AHS drivers. Having close friends that smoked, cargo driving, and lower education levels were associated with current smoking.

A Vehicle Active Safety Model: Vehicle Speed Control Based on Driver Vigilance Detection Using Wearable EEG and Sparse Representation.

PubMed

Zhang, Zutao; Luo, Dianyuan; Rasim, Yagubov; Li, Yanjun; Meng, Guanjun; Xu, Jian; Wang, Chunbai

2016-02-19

In this paper, we present a vehicle active safety model for vehicle speed control based on driver vigilance detection using low-cost, comfortable, wearable electroencephalographic (EEG) sensors and sparse representation. The proposed system consists of three main steps, namely wireless wearable EEG collection, driver vigilance detection, and vehicle speed control strategy. First of all, a homemade low-cost comfortable wearable brain-computer interface (BCI) system with eight channels is designed for collecting the driver's EEG signal. Second, wavelet de-noising and down-sample algorithms are utilized to enhance the quality of EEG data, and Fast Fourier Transformation (FFT) is adopted to extract the EEG power spectrum density (PSD). In this step, sparse representation classification combined with k-singular value decomposition (KSVD) is firstly introduced in PSD to estimate the driver's vigilance level. Finally, a novel safety strategy of vehicle speed control, which controls the electronic throttle opening and automatic braking after driver fatigue detection using the above method, is presented to avoid serious collisions and traffic accidents. The simulation and practical testing results demonstrate the feasibility of the vehicle active safety model.

A Roadmap for Interpreting the Literature on Vision and Driving

PubMed Central

Owsley, Cynthia; Wood, Joanne M.; McGwin, Gerald

2015-01-01

Over the past several decades there has been a sharp increase in the number of studies focused on the relationship between vision and driving. The intensified scientific attention to this topic has most likely been stimulated by the lack of an evidence-basis for determining vision standards for driving licensure and a poor understanding about how vision impairment impacts driver safety and performance. Clinicians depend on the scientific literature on vision and driving as a resource to appropriately advise visually impaired patients about driving fitness. Policy makers also depend on the scientific literature in order to develop guidelines that are evidence-based and are thus fair to persons who are visually impaired. Thus it is important for clinicians and policy makers alike to understand how various study designs and measurement methods should be appropriately interpreted so that the conclusions and recommendations they make based on this literature are not overly broad, too narrowly constrained, or even misguided. In this overview, based on our 25 years of experience in this field, we offer a methodological framework to guide interpretations of studies on vision and driving, which can also serve as a heuristic for researchers in the area. Here we discuss research designs and general measurement methods for the study of vision as they relate to driver safety, driver performance, and driver-centered (self-reported) outcomes. PMID:25753389

Changing drivers' minds: the evaluation of an advanced driver coaching system.

PubMed

Stanton, N A; Walker, G H; Young, M S; Kazi, T; Salmon, P M

2007-08-01

This paper reports on the study of an advanced driver coaching system. The study distinguishes between different types of post-licensure programmes in order to explore a system based on a model of identifying and responding to hazards, called 'information, position, speed, gear and acceleration' (IPSGA). Previous literature has been sceptical about the benefits of advanced driver education; thus, the current study was designed to control for the effects of coaching drivers in the 'IPSGA' system (the treatment group) against the effects of being accompanied (control group 1), as well as the mere effects of time (control group 2). Measures were taken before the driver coaching began (as a baseline measure) and again after 8 weeks (to see if any changes had occurred). These measures included driver knowledge via a post-drive interview, observations of driving skill and driver attitude using a locus of control scale. The results suggest that advanced driver coaching using the IPSGA system had a beneficial effect on all of these measures. Drivers in the coaching condition improved their situation awareness, driving skills and reduced attributions of external locus of control. The study lends support to the case for one-to-one individualized driver coaching using a systematic model of driving.

Preface to the special section on human factors and automation in vehicles: designing highly automated vehicles with the driver in mind.

PubMed

Merat, Natasha; Lee, John D

2012-10-01

This special section brings together diverse research regarding driver interaction with advanced automotive technology to guide design of increasingly automated vehicles. Rapidly evolving vehicle automation will likely change cars and trucks more in the next 5 years than the preceding 50, radically redefining what it means to drive. This special section includes 10 articles from European and North American researchers reporting simulator and naturalistic driving studies. Little research has considered the consequences of fully automated driving, with most focusing on lane-keeping and speed control systems individually. The studies reveal two underlying design philosophies: automate driving versus support driving. Results of several studies, consistent with previous research in other domains, suggest that the automate philosophy can delay driver responses to incidents in which the driver has to intervene and take control from the automation. Understanding how to orchestrate the transfer or sharing of control between the system and the driver, particularly in critical incidents, emerges as a central challenge. Designers should not assume that automation can substitute seamlessly for a human driver, nor can they assume that the driver can safely accommodate the limitations of automation. Designers, policy makers, and researchers must give careful consideration to what role the person should have in highly automated vehicles and how to support the driver if the driver is to be responsible for vehicle control. As in other domains, driving safety increasingly depends on the combined performance of the human and automation, and successful designs will depend on recognizing and supporting the new roles of the driver.

Driver Behavior During Overtaking Maneuvers from the 100-Car Naturalistic Driving Study.

PubMed

Chen, Rong; Kusano, Kristofer D; Gabler, Hampton C

2015-01-01

Lane changes with the intention to overtake the vehicle in front are especially challenging scenarios for forward collision warning (FCW) designs. These overtaking maneuvers can occur at high relative vehicle speeds and often involve no brake and/or turn signal application. Therefore, overtaking presents the potential of erroneously triggering the FCW. A better understanding of driver behavior during lane change events can improve designs of this human-machine interface and increase driver acceptance of FCW. The objective of this study was to aid FCW design by characterizing driver behavior during lane change events using naturalistic driving study data. The analysis was based on data from the 100-Car Naturalistic Driving Study, collected by the Virginia Tech Transportation Institute. The 100-Car study contains approximately 1.2 million vehicle miles of driving and 43,000 h of data collected from 108 primary drivers. In order to identify overtaking maneuvers from a large sample of driving data, an algorithm to automatically identify overtaking events was developed. The lead vehicle and minimum time to collision (TTC) at the start of lane change events was identified using radar processing techniques developed in a previous study. The lane change identification algorithm was validated against video analysis, which manually identified 1,425 lane change events from approximately 126 full trips. Forty-five drivers with valid time series data were selected from the 100-Car study. From the sample of drivers, our algorithm identified 326,238 lane change events. A total of 90,639 lane change events were found to involve a closing lead vehicle. Lane change events were evenly distributed between left side and right side lane changes. The characterization of lane change frequency and minimum TTC was divided into 10 mph speed bins for vehicle travel speeds between 10 and 90 mph. For all lane change events with a closing lead vehicle, the results showed that drivers change lanes most frequently in the 40-50 mph speed range. Minimum TTC was found to increase with travel speed. The variability in minimum TTC between drivers also increased with travel speed. This study developed and validated an algorithm to detect lane change events in the 100-Car Naturalistic Driving Study and characterized lane change events in the database. The characterization of driver behavior in lane change events showed that driver lane change frequency and minimum TTC vary with travel speed. The characterization of overtaking maneuvers from this study will aid in improving the overall effectiveness of FCW systems by providing active safety system designers with further understanding of driver action in overtaking maneuvers, thereby increasing system warning accuracy, reducing erroneous warnings, and improving driver acceptance.

Development of Accomodation Models for Soldiers in Vehicles: Driver

DTIC Science & Technology

2014-09-01

human needs and performance. A small section of this standard addresses the design of vehicle seats and the layout of the driver workstation...drivers and passengers (squad). The study was designed to focus on tactical vehicle (truck) designs with fixed driver heel points and H30 values...fore-aft and vertically, along with adjusting the seat back angle, to obtain a comfortable driving position. The Soldier’s posture and seat adjustments

An Analysis of a Contingency Program on Designated Drivers at a College Bar

ERIC Educational Resources Information Center

Kazbour, Richard R.; Bailey, Jon S.

2010-01-01

The present study evaluated the effects of prompts and incentives on designated drivers in a bar. We defined the dependent variable as the percentage of customers either functioning as or riding with a designated driver. We used an ABCA design to evaluate the effectiveness of prompts and incentives on the dependent variable. Results indicated that…

Present status and future prospects of heavy ion beams as drivers for ICF

NASA Astrophysics Data System (ADS)

Godlove, Terry F.

1986-01-01

A candidate driver for a practical inertial fusion reactor system must, among other characteristics, be cost effective and reliable for the parameters required by the fusion target and the remainder of the system. Although the history of large particle accelerators provides abundant evidence of their reliability at high repetition rates, their capital cost for the fusion application has been open to question. Attempts to design cost effective systems began with accelerators based on currently available technology such as RF linacs and storage rings. The West German HIBALL and the Japanese HIBLIC are examples of this initial effort. These designs are sufficiently credible that a strong argument can be made for the heavy ion method in general, but to reduce the cost per unit power it was found necessary to design for large scale, hence high capital cost. Emphasis in the U.S. shifted to newer technologies which offer hope of significant improvement in cost. In this paper the status of various heavy ion driver designs are compared with currently perceived requirements in order to illustrate their potential and assess their development needs.

Evaluation of insight training of ambulance drivers in Sweden using DART, a new e-learning tool.

PubMed

Albertsson, Pontus; Sundström, Anna

2011-12-01

The aim of the study was to evaluate whether a new e-learning tool for insight training of ambulance drivers can have an effect on drivers' driving behaviors, perceived driving competence, competence to assess risks, self-reflection, and safety attitudes. A quasi-experimental study design, with participants nonrandomly assigned into a control and intervention group, was used. The intervention group participated in the insight-training course and the control group did not. Both groups completed a self- and peer assessment online questionnaire before and after the training. The main finding is that the ambulance drivers assessed themselves through the instruments after the training, with the e-learning tool Driver Access Recording Tool (DART), as safer drivers in the areas of speed adaptation, closing up, and overtaking. In the answers from the group-based evaluation, the ambulance drivers responded that they were more reflective/analytical, had increased their risk awareness, and had changed their driving behaviors. After insight training, the ambulance drivers in this study assessed themselves as safer drivers in several important areas, including speed adaptation, closing up, and overtaking. In future training of ambulance drivers there should be more focus on insight training instead of previous training focusing on maneuvering capabilities.

Directing driver attention with augmented reality cues

PubMed Central

Rusch, Michelle L.; Schall, Mark C.; Gavin, Patrick; Lee, John D.; Dawson, Jeffrey D.; Vecera, Shaun; Rizzo, Matthew

2013-01-01

This simulator study evaluated the effects of augmented reality (AR) cues designed to direct the attention of experienced drivers to roadside hazards. Twenty-seven healthy middle-aged licensed drivers with a range of attention capacity participated in a 54 mile (1.5 hour) drive in an interactive fixed-base driving simulator. Each participant received AR cues to potential roadside hazards in six simulated straight (9 mile long) rural roadway segments. Drivers were evaluated on response time for detecting a potentially hazardous event, detection accuracy for target (hazard) and non-target objects, and headway with respect to the hazards. Results showed no negative outcomes associated with interference. AR cues did not impair perception of non-target objects, including for drivers with lower attentional capacity. Results showed near significant response time benefits for AR cued hazards. AR cueing increased response rate for detecting pedestrians and warning signs but not vehicles. AR system false alarms and misses did not impair driver responses to potential hazards. PMID:24436635

Conceptual design of data acquisition and control system for two Rf driver based negative ion source for fusion R&D

NASA Astrophysics Data System (ADS)

Soni, Jigensh; Yadav, R. K.; Patel, A.; Gahlaut, A.; Mistry, H.; Parmar, K. G.; Mahesh, V.; Parmar, D.; Prajapati, B.; Singh, M. J.; Bandyopadhyay, M.; Bansal, G.; Pandya, K.; Chakraborty, A.

2013-02-01

Twin Source - An Inductively coupled two RF driver based 180 kW, 1 MHz negative ion source experimental setup is initiated at IPR, Gandhinagar, under Indian program, with the objective of understanding the physics and technology of multi-driver coupling. Twin Source [1] (TS) also provides an intermediate platform between operational ROBIN [2] [5] and eight RF drivers based Indian test facility -INTF [3]. A twin source experiment requires a central system to provide control, data acquisition and communication interface, referred as TS-CODAC, for which a software architecture similar to ITER CODAC core system has been decided for implementation. The Core System is a software suite for ITER plant system manufacturers to use as a template for the development of their interface with CODAC. The ITER approach, in terms of technology, has been adopted for the TS-CODAC so as to develop necessary expertise for developing and operating a control system based on the ITER guidelines as similar configuration needs to be implemented for the INTF. This cost effective approach will provide an opportunity to evaluate and learn ITER CODAC technology, documentation, information technology and control system processes, on an operational machine. Conceptual design of the TS-CODAC system has been completed. For complete control of the system, approximately 200 Nos. control signals and 152 acquisition signals are needed. In TS-CODAC, control loop time required is within the range of 5ms - 10 ms, therefore for the control system, PLC (Siemens S-7 400) has been chosen as suggested in the ITER slow controller catalog. For the data acquisition, the maximum sampling interval required is 100 micro second, and therefore National Instruments (NI) PXIe system and NI 6259 digitizer cards have been selected as suggested in the ITER fast controller catalog. This paper will present conceptual design of TS -CODAC system based on ITER CODAC Core software and applicable plant system integration processes.

ISG hybrid powertrain: a rule-based driver model incorporating look-ahead information

NASA Astrophysics Data System (ADS)

Shen, Shuiwen; Zhang, Junzhi; Chen, Xiaojiang; Zhong, Qing-Chang; Thornton, Roger

2010-03-01

According to European regulations, if the amount of regenerative braking is determined by the travel of the brake pedal, more stringent standards must be applied, otherwise it may adversely affect the existing vehicle safety system. The use of engine or vehicle speed to derive regenerative braking is one way to avoid strict design standards, but this introduces discontinuity in powertrain torque when the driver releases the acceleration pedal or applies the brake pedal. This is shown to cause oscillations in the pedal input and powertrain torque when a conventional driver model is adopted. Look-ahead information, together with other predicted vehicle states, are adopted to control the vehicle speed, in particular, during deceleration, and to improve the driver model so that oscillations can be avoided. The improved driver model makes analysis and validation of the control strategy for an integrated starter generator (ISG) hybrid powertrain possible.

Modeling The Frontal Collison In Vehicles And Determining The Degree Of Injury On The Driver

NASA Astrophysics Data System (ADS)

Oţăt, Oana Victoria

2015-09-01

The present research study aims at analysing the kinematic and the dynamic behaviour of the vehicle's driver in a frontal collision. Hence, a subsequent objective of the research paper is to establish the degree of injury suffered by the driver. Therefore, in order to achieve the objectives set, first, we had to define the type of the dummy placed in the position of the driver, and then to design the three-element assembly, i.e. the chair-steering wheel-dashboard assembly. Based on this model, the following step focused on the positioning of the dummy, which has also integrated the defining of the contacts between the components of the dummy and the seat elements. Seeking to model such a behaviour that would highly accurately reflect the driver's movements in a frontal collision, passive safety systems have also been defined and simulated, namely the seatbelt and the frontal airbag.

The effects of focused attention training (FOCAL) on the duration of novice drivers' glances inside the vehicle

PubMed Central

Pradhan, A.K.; Divekar, G.; Masserang, K.; Romoser, M.; Zafian, T.; Blomberg, R.D.; Thomas, F.D.; Reagan, I.; Knodler, M.; Pollatsek, A.; Fisher, D.L.

2011-01-01

Several studies have documented that the failure of drivers to attend to the forward roadway for a period lasting longer than 2-3 seconds is a major cause of highway crashes. Moreover, several studies have demonstrated that novice drivers are more likely to glance away from the roadway than experienced drivers for extended periods when attempting to do a task inside the vehicle. The present study examines the efficacy of a PC-based training program (FOCAL) designed to teach novice drivers not to glance away for these extended periods of time. A FOCAL-trained group was compared to a placebo-trained group in an on-road test, and the FOCAL-trained group made significantly fewer glances away from the roadway that were more than 2 seconds than the placebo-trained group. Other measures indicated an advantage for the FOCAL-trained group as well. PMID:21973003

Prevalence of drug use among drivers based on mandatory, random tests in a roadside survey

PubMed Central

Alcañiz, Manuela; Guillen, Montserrat

2018-01-01

Background In the context of road safety, this study aims to examine the prevalence of drug use in a random sample of drivers. Methods A stratified probabilistic sample was designed to represent vehicles circulating on non-urban roads. Random drug tests were performed during autumn 2014 on 521 drivers in Catalonia (Spain). Participation was mandatory. The prevalence of drug driving for cannabis, methamphetamines, amphetamines, cocaine, opiates and benzodiazepines was assessed. Results The overall prevalence of drug use is 16.4% (95% CI: 13.9; 18.9) and affects primarily younger male drivers. Drug use is similarly prevalent during weekdays and on weekends, but increases with the number of occupants. The likelihood of being positive for methamphetamines is significantly higher for drivers of vans and lorries. Conclusions Different patterns of use are detected depending on the drug considered. Preventive drug tests should not only be conducted on weekends and at night-time, and need to be reinforced for drivers of commercial vehicles. Active educational campaigns should focus on the youngest age-group of male drivers. PMID:29920542

The driver, the road, the rules … and the rest? A systems-based approach to young driver road safety.

PubMed

Scott-Parker, B; Goode, N; Salmon, P

2015-01-01

The persistent overrepresentation of young drivers in road crashes is universally recognised. A multitude of factors influencing their behaviour and safety have been identified through methods including crash analyses, simulated and naturalistic driving studies, and self-report measures. Across the globe numerous, diverse, countermeasures have been implemented; the design of the vast majority of these has been informed by a driver-centric approach. An alternative approach gaining popularity in transport safety is the systems approach which considers not only the characteristics of the individual, but also the decisions and actions of other actors within the road transport system, along with the interactions amongst them. This paper argues that for substantial improvements to be made in young driver road safety, what has been learnt from driver-centric research needs to be integrated into a systems approach, thus providing a holistic appraisal of the young driver road safety problem. Only then will more effective opportunities and avenues for intervention be realised. Copyright © 2014 Elsevier Ltd. All rights reserved.

Process-based Cost Estimation for Ramjet/Scramjet Engines

NASA Technical Reports Server (NTRS)

Singh, Brijendra; Torres, Felix; Nesman, Miles; Reynolds, John

2003-01-01

Process-based cost estimation plays a key role in effecting cultural change that integrates distributed science, technology and engineering teams to rapidly create innovative and affordable products. Working together, NASA Glenn Research Center and Boeing Canoga Park have developed a methodology of process-based cost estimation bridging the methodologies of high-level parametric models and detailed bottoms-up estimation. The NASA GRC/Boeing CP process-based cost model provides a probabilistic structure of layered cost drivers. High-level inputs characterize mission requirements, system performance, and relevant economic factors. Design alternatives are extracted from a standard, product-specific work breakdown structure to pre-load lower-level cost driver inputs and generate the cost-risk analysis. As product design progresses and matures the lower level more detailed cost drivers can be re-accessed and the projected variation of input values narrowed, thereby generating a progressively more accurate estimate of cost-risk. Incorporated into the process-based cost model are techniques for decision analysis, specifically, the analytic hierarchy process (AHP) and functional utility analysis. Design alternatives may then be evaluated not just on cost-risk, but also user defined performance and schedule criteria. This implementation of full-trade study support contributes significantly to the realization of the integrated development environment. The process-based cost estimation model generates development and manufacturing cost estimates. The development team plans to expand the manufacturing process base from approximately 80 manufacturing processes to over 250 processes. Operation and support cost modeling is also envisioned. Process-based estimation considers the materials, resources, and processes in establishing cost-risk and rather depending on weight as an input, actually estimates weight along with cost and schedule.

A Driving Simulator Evaluation of Cross-Sectional Design Elements and the Resulting Driving Behaviors

DOT National Transportation Integrated Search

2017-09-01

This research explores the relationship between the cross-sectional design elements and the impact on selected driver attributes such as speed profiles and lateral positioning. In this experiment a traditional collector-type base roadway of 1.5 miles...

Vehicle-to-Grid Automatic Load Sharing with Driver Preference in Micro-Grids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yubo; Nazaripouya, Hamidreza; Chu, Chi-Cheng

Integration of Electrical Vehicles (EVs) with power grid not only brings new challenges for load management, but also opportunities for distributed storage and generation. This paper comprehensively models and analyzes distributed Vehicle-to-Grid (V2G) for automatic load sharing with driver preference. In a micro-grid with limited communications, V2G EVs need to decide load sharing based on their own power and voltage profile. A droop based controller taking into account driver preference is proposed in this paper to address the distributed control of EVs. Simulations are designed for three fundamental V2G automatic load sharing scenarios that include all system dynamics of suchmore » applications. Simulation results demonstrate that active power sharing is achieved proportionally among V2G EVs with consideration of driver preference. In additional, the results also verify the system stability and reactive power sharing analysis in system modelling, which sheds light on large scale V2G automatic load sharing in more complicated cases.« less

Redesign of Transjakarta Bus Driver's Cabin

NASA Astrophysics Data System (ADS)

Mardi Safitri, Dian; Azmi, Nora; Singh, Gurbinder; Astuti, Pudji

2016-02-01

Ergonomic risk at work stations with type Seated Work Control was one of the problems faced by Transjakarta bus driver. Currently “Trisakti” type bus, one type of bus that is used by Transjakarta in corridor 9, serving route Pinang Ranti - Pluit, gained many complaints from drivers. From the results of Nordic Body Map questionnaires given to 30 drivers, it was known that drivers feel pain in the neck, arms, hips, and buttocks. Allegedly this was due to the seat position and the button/panel bus has a considerable distance range (1 meter) to be achieved by drivers. In addition, preliminary results of the questionnaire using Workstation Checklist identified their complaints about uncomfortable cushion, driver's seat backrest, and the exact position of the AC is above the driver head. To reduce the risk level of ergonomics, then did research to design the cabin by using a generic approach to designing products. The risk analysis driver posture before the design was done by using Rapid Upper Limb Assessment (RULA), Rapid Entire Body Assessment (REBA), and Quick Exposure Checklist (QEC), while the calculation of the moment the body is done by using software Mannequin Pro V10.2. Furthermore, the design of generic products was done through the stages: need metric-matrix, house of quality, anthropometric data collection, classification tree concept, concept screening, scoring concept, design and manufacture of products in the form of two-dimensional. While the design after design risk analysis driver posture was done by using RULA, REBA, and calculation of moments body as well as the design visualized using software 3DMax. From the results of analysis before the draft design improvements cabin RULA obtained scores of 6, REBA 9, and the result amounted to 57.38% QEC and moment forces on the back is 247.3 LbF.inch and on the right hip is 72.9 LbF.in. While the results of the proposed improvements cabin design RULA obtained scores of 3, REBA 4, and the moment of force on the back is 90.3 LbF.in and on the right hip is 70.6 LbF.in. This indicated improvement cabin design can reduce ergonomic risk with lower scores on several parts of the body.

The California corridor transportation system: A design summary

NASA Technical Reports Server (NTRS)

1990-01-01

A design group was assembled to find and research criteria relevent to the design of a California Corridor Transportation System. The efforts of this group included defining the problem, conducting a market analysis, formulation of a demand model, identification and evaluation of design drivers, and the systematic development of a solution. The problems of the current system were analyzed and used to determine design drivers, which were divided into the broad categories of cost, convenience, feasibility, environment, safety, and social impact. The relative importance of individual problems was addressed, resulting in a hierarchy of design drivers. Where possible, methods of evaluating the relative merit of proposed systems with respect to each driver were developed. Short takeoff vertical landing aircraft concepts are also discussed for supersonic fighters.

Design of a steering stabilizer based on CAN bus

NASA Astrophysics Data System (ADS)

Zhan, Zhaomin; Yan, Yibin

2018-04-01

This design realizes a posture correction device of griping steering wheel based on CAN bus, which is embedded in the steering wheel of vehicles. The system aims to detect the drivers' abnormal griping postures and provides drivers with classification alerts, by combining the recorded griping postures data and the vehicle speed data that are obtained via the CAN bus. The warning information are automatically stored and retained in the device for 12 months. To enhance the alerting effect, the count of this warning message for both the latest month and the last 12 months are displayed on the dashboard panel. In addition to prevent itself from being blocked and self-detect any faults in advance, the appliance also provide a self-test function, which will communicate with the integrated instrument system in vehicle and do simulation test right after the vehicle power on. This appliance can help to urge and ensure drivers to operate the steering wheel correctly, effectively, and timely; prevent some typical incorrect behaviors which commonly happen along with the change of griping postures, such as the using cellphone, and ultimately, reduce the incidence of traffic accidents.

A mediation model linking dispatcher leadership and work ownership with safety climate as predictors of truck driver safety performance.

PubMed

Zohar, Dov; Huang, Yueng-hsiang; Lee, Jin; Robertson, Michelle

2014-01-01

The study was designed to test the effect of safety climate on safety behavior among lone employees whose work environment promotes individual rather than consensual or shared climate perceptions. The paper presents a mediation path model linking psychological (individual-level) safety climate antecedents and consequences as predictors of driving safety of long-haul truck drivers. Climate antecedents included dispatcher (distant) leadership and driver work ownership, two contextual attributes of lone work, whereas its proximal consequence included driving safety. Using a prospective design, safety outcomes, consisting of hard-braking frequency (i.e. traffic near-miss events) were collected six months after survey completion, using GPS-based truck deceleration data. Results supported the hypothesized model, indicating that distant leadership style and work ownership promote psychological safety climate perceptions, with subsequent prediction of hard-braking events mediated by driving safety. Theoretical and practical implications for studying safety climate among lone workers in general and professional drivers in particular are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Work, Train, Win: Work-Based Learning Design and Management for Productivity Gains. OECD Education Working Papers, No. 135

ERIC Educational Resources Information Center

Kis, Viktoria

2016-01-01

Realising the potential of work-based learning schemes as a driver of productivity requires careful design and support. The length of work-based learning schemes should be adapted to the profile of productivity gains. A scheme that is too long for a given skill set might be unattractive for learners and waste public resources, but a scheme that is…

[Determining the car driver's position at the moment of the frontal crash with a moving KAMAZ truck].

PubMed

Gusarov, A A; Fetisov, V A; Smirenin, S A

2016-01-01

This article is designed to report the results of the comprehensive forensic medical and autotechnical expertise for determining the positions of the driver and the first seat passenger of the GAS-3110 car at the moment of the frontal crash with a KAMAZ-5312 truck. The comparative analysis of the injuries in two subjects one of whom died as a result of the given accident made it possible to conclude that he had occupied the driver's seat in the car. The differential diagnosis was based on the peculiarities of the injuries to the upper extremities with the predominance of the most severe wounds at the right side of the body. Also taken into consideration were the specific conditions of the given frontal collision, design of the GAS-3110 passenger compartment, winter season, night time, and possible neglect of the passive safety means, etc.

Human Factors Design Of Automated Highway Systems: Scenario Definition

DOT National Transportation Integrated Search

1995-09-01

Attention to driver acceptance and performance issues during system design will be key to the success of the Automated Highway System (AHS). A first step in the process of defining driver roles and driver-system interface requirements of AHS is the d...

Evaluation of four steering wheels to determine driver hand placement in a static environment.

PubMed

Mossey, Mary E; Xi, Yubin; McConomy, Shayne K; Brooks, Johnell O; Rosopa, Patrick J; Venhovens, Paul J

2014-07-01

While much research exists on occupant packaging both proprietary and in the literature, more detailed research regarding user preferences for subjective ratings of steering wheel designs is sparse in published literature. This study aimed to explore the driver interactions with production steering wheels in four vehicles by using anthropometric data, driver hand placement, and driver grip design preferences for Generation-Y and Baby Boomers. In this study, participants selected their preferred grip diameter, responded to a series of questions about the steering wheel grip as they sat in four vehicles, and rank ordered their preferred grip design. Thirty-two male participants (16 Baby Boomers between ages 47 and 65 and 16 Generation-Y between ages 18 and 29) participated in the study. Drivers demonstrated different gripping behavior between vehicles and between groups. Recommendations for future work in steering wheel grip design and naturalistic driver hand positioning are discussed. Copyright © 2014. Published by Elsevier Ltd.

Wildlife Warning Signs: Public Assessment of Components, Placement and Designs to Optimise Driver Response.

PubMed

Bond, Amy R F; Jones, Darryl N

2013-12-17

Wildlife warning signs are the most commonly used and widespread form of road impact mitigation, aimed at reducing the incidence of wildlife-vehicle collisions. Evidence of the effectiveness of currently used signs is rare and often indicates minimal change in driver behaviour. Improving the design of these signs to increase the likelihood of appropriate driver response has the potential to reduce the incidence of wildlife-vehicle collisions. This study aimed to examine and assess the opinions of drivers on wildlife warning sign designs through a public opinion survey. Three currently used sign designs and five alternative sign designs were compared in the survey. A total of 134 drivers were surveyed. The presence of temporal specifications and an updated count of road-killed animals on wildlife warning signs were assessed, as well as the position of the sign. Drivers' responses to the eight signs were scaled separately at three speed limits and participants indicated the sign to which they were most likely to respond. Three signs consistently ranked high. The messages conveyed by these signs and their prominent features were explored. Animal-activated and vehicle speed-activated signs were ranked very highly by participants. Extensive field trials of various sign designs are needed to further this research into optimizing wildlife warning sign designs.

Design and Qualification of a SmallSat Stepper Motor Driver, Flight Results On-Board the Yes2 Satellite

NASA Astrophysics Data System (ADS)

Graczyk, R.; Kruijff, M.; Spiliotopoulos, I.

2008-08-01

Drivers for stepper motors are a commonly required critical technology for small satellites. This paper highlights the stepper driver design, test, and mission performance for the second Young Engineers' Satellite (YES2). The unit integrates the required digital and power parts and was developed with generic low-cost satellite applications in mind. One of the key mechanisms in YES2 is a friction brake containing a stepper motor which is in turn controlled by a stepper driver. The friction brake was used to control the deployment speed such that the tether deployed according to a pre-described two-stage trajectory. The stepper driver was itself commanded by an on-board computer that used tether deployment data as input and provided the new required position of the brake as output. The stepper driver design was driven by the requirements of a low cost yet reliable redundant design, use of a micro-controller and software commonly known to students, very small dimension, good thermal behavior and capable of delivering high torque at high efficiency. The work followed as much as possible ESA's design standards and was qualified by electromagnetic compatibility, thermal vacuum and shaker tests. It was functionally tested in real-time ground tether deployments. Mission data shows the stepper driver performed well in flight.

Augmented reality cues to assist older drivers with gap estimation for left-turns.

PubMed

Rusch, Michelle L; Schall, Mark C; Lee, John D; Dawson, Jeffrey D; Rizzo, Matthew

2014-10-01

The objective of this study was to assess the effects of augmented reality (AR) cues designed to assist middle-aged and older drivers with a range of UFOV impairments, judging when to make left-turns across oncoming traffic. Previous studies have shown that AR cues can help middle-aged and older drivers respond to potential roadside hazards by increasing hazard detection without interfering with other driving tasks. Intersections pose a critical challenge for cognitively impaired drivers, prone to misjudge time-to-contact with oncoming traffic. We investigated whether AR cues improve or interfere with hazard perception in left-turns across oncoming traffic for drivers with age-related cognitive decline. Sixty-four middle-aged and older drivers with a range of UFOV impairment judged when it would be safe to turn left across oncoming traffic approaching the driver from the opposite direction in a rural stop-sign controlled intersection scenario implemented in a static base driving simulator. Outcome measures used to evaluate the effectiveness of AR cueing included: Time-to-Contact (TTC), Gap Time Variation (GTV), Response Rate, and Gap Response Variation (GRV). All drivers estimated TTCs were shorter in cued than in uncued conditions. In addition, drivers responded more often in cued conditions than in uncued conditions and GRV decreased for all drivers in scenarios that contained AR cues. For both TTC and response rate, drivers also appeared to adjust their behavior to be consistent with the cues, especially drivers with the poorest UFOV scores (matching their behavior to be close to middle-aged drivers). Driver ratings indicated that cueing was not considered to be distracting. Further, various conditions of reliability (e.g., 15% miss rate) did not appear to affect performance or driver ratings. Copyright © 2014 Elsevier Ltd. All rights reserved.

AUGMENTED REALITY CUES TO ASSIST OLDER DRIVERS WITH GAP ESTIMATION FOR LEFT-TURNS

PubMed Central

Rusch, Michelle L.; Schall, Mark C.; Lee, John D.; Dawson, Jeffrey D.; Rizzo, Matthew

2014-01-01

The objective of this study was to assess the effects of augmented reality (AR) cues designed to assist middle-aged and older drivers with a range of UFOV impairments, judging when to make left-turns across oncoming traffic. Previous studies have shown that AR cues can help middle-aged and older drivers respond to potential roadside hazards by increasing hazard detection without interfering with other driving tasks. Intersections pose a critical challenge for cognitively impaired drivers, prone to misjudge time-to-contact with oncoming traffic. We investigated whether AR cues improve or interfere with hazard perception in left-turns across oncoming traffic for drivers with age-related cognitive decline. Sixty-four middle-aged and older drivers with a range of UFOV impairment judged when it would be safe to turn left across oncoming traffic approaching the driver from the opposite direction in a rural stop-sign controlled intersection scenario implemented in a static base driving simulator. Outcome measures used to evaluate the effectiveness of AR cueing included: Time-to-Contact (TTC), Gap Time Variation (GTV), Response Rate, and Gap Response Variation (GRV). All drivers estimated TTCs were shorter in cued than in uncued conditions. In addition, drivers responded more often in cued conditions than in uncued conditions and GRV decreased for all drivers in scenarios that contained AR cues. For both TTC and response rate, drivers also appeared to adjust their behavior to be consistent with the cues, especially drivers with the poorest UFOV scores (matching their behavior to be close to middle-aged drivers). Driver ratings indicated that cueing was not considered to be distracting. Further, various conditions of reliability (e.g., 15% miss rate) did not appear to affect performance or driver ratings. PMID:24950128

77 FR 19026 - Designation of Syrian Arab Republic for Temporary Protected Status

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-29

...\\ The Secretary can designate a foreign state for TPS based on one of three circumstances. One... Syrian military have also shot unarmed protestors, including children, medical doctors, ambulance drivers...--Syria.'' Do I need to submit additional supporting documentation? If one or more of the questions listed...

The Role of Designated Driver Programs in the Prevention of Alcohol-Impaired Driving: A Critical Reassessment [and] Designated Driver Programs: A Commentary on the DeJong and Wallack Article.

ERIC Educational Resources Information Center

DeJong, William; And Others

1992-01-01

Focus on the designated driver strategy by broadcasters and the alcohol industry deflects attention from other alcohol-related problems and the factors influencing underage alcohol consumption. Strategies should emphasize sobriety checkpoints, no sales to minors, advertising reform, and excise taxes on alcohol. (SK)

Lane change warning threshold based on driver perception characteristics.

PubMed

Wang, Chang; Sun, Qinyu; Fu, Rui; Li, Zhen; Zhang, Qiong

2018-08-01

Lane Change Warning system (LCW) is exploited to alleviate driver workload and improve the safety performance of lane changes. Depending on the secure threshold, the lane change warning system could transmit caution to drivers. Although the system possesses substantial benefits, it may perturb the conventional operating of the driver and affect driver judgment if the warning threshold does not conform to the driver perception of safety. Therefore, it is essential to establish an appropriate warning threshold to enhance the accuracy rate and acceptability of the lane change warning system. This research aims to identify the threshold that conforms to the driver perception of the ability to safely change lanes with a rear vehicle fast approaching. We propose a theoretical warning model of lane change based on a safe minimum distance and deceleration of the rear vehicle. For the purpose of acquiring the different safety levels of lane changes, 30 licensed drivers are recruited and we obtain the extreme moments represented by driver perception characteristics from a Front Extremity Test and a Rear Extremity Test implemented on the freeway. The required deceleration of the rear vehicle corresponding to the extreme time is calculated according to the proposed model. In light of discrepancies in the deceleration in these extremity experiments, we determine two levels of a hierarchical warning system. The purpose of the primary warning is to remind drivers of the existence of potentially dangerous vehicles and the second warning is used to warn the driver to stop changing lanes immediately. We use the signal detection theory to analyze the data. Ultimately, we confirm that the first deceleration threshold is 1.5 m/s 2 and the second deceleration threshold is 2.7 m/s 2 . The findings provide the basis for the algorithm design of LCW and enhance the acceptability of the intelligent system. Copyright © 2018 Elsevier Ltd. All rights reserved.

Scoping the parameter space for demo and the engineering test facility (ETF)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meier, Wayne R.

1999-01-19

In our IFE development plan, we have set a goal of building an Engineering Test Facility (ETF) for a total cost of $2B and a Demo for $3B. In Mike Campbell' s presentation at Madison, we included a viewgraph with an example Demo that had 80 to 250 MWe of net power and showed a plausible argument that it could cost less than $3B. In this memo, I examine the design space for the Demo and then briefly for the ETF. Instead of attempting to estimate the costs of the drivers, I pose the question in a way to definemore » R&D goals: As a function of key design and performance parameters, how much can the driver cost if the total facility cost is limited to the specified goal? The design parameters examined for the Demo included target gain, driver energy, driver efficiency, and net power output. For the ETF; the design parameters are target gain, driver energy, and target yield. The resulting graphs of allowable driver cost determine the goals that the driver R&D programs must seek to meet.« less

Evaluating large-scale health programmes at a district level in resource-limited countries.

PubMed

Svoronos, Theodore; Mate, Kedar S

2011-11-01

Recent experience in evaluating large-scale global health programmes has highlighted the need to consider contextual differences between sites implementing the same intervention. Traditional randomized controlled trials are ill-suited for this purpose, as they are designed to identify whether an intervention works, not how, when and why it works. In this paper we review several evaluation designs that attempt to account for contextual factors that contribute to intervention effectiveness. Using these designs as a base, we propose a set of principles that may help to capture information on context. Finally, we propose a tool, called a driver diagram, traditionally used in implementation that would allow evaluators to systematically monitor changing dynamics in project implementation and identify contextual variation across sites. We describe an implementation-related example from South Africa to underline the strengths of the tool. If used across multiple sites and multiple projects, the resulting driver diagrams could be pooled together to form a generalized theory for how, when and why a widely-used intervention works. Mechanisms similar to the driver diagram are urgently needed to complement existing evaluations of large-scale implementation efforts.

Evaluation of the driver's cab in the Rc5 engine.

PubMed

Hedberg, G

1987-03-01

The opinion of engine drivers concerning the design of the cab in a new engine (Rc5, ASEA, Sweden) is surveyed in the present study, which is aimed at recommendations for further improvements of the new cab. Fifty engine drivers from the northern part of Sweden (Ange, Vannas and Boden), who had been driving the new engine, were selected at random to answer a specially designed questionnaire. Most of the drivers considered the new cab as better than the old one (Rc4) in several respects. Particularly appreciated was an adjustable footrest, on which the safety regulator pedal was fitted, which enabled an individually adjusted position for driving. They also preferred the automatic brake valve located close to the driver and with its movements in a sagittal direction. A number of proposals for further improvement of the cab are presented in order to attain an optimally designed driver's cab.

Image processing system design for microcantilever-based optical readout infrared arrays

NASA Astrophysics Data System (ADS)

Tong, Qiang; Dong, Liquan; Zhao, Yuejin; Gong, Cheng; Liu, Xiaohua; Yu, Xiaomei; Yang, Lei; Liu, Weiyu

2012-12-01

Compared with the traditional infrared imaging technology, the new type of optical-readout uncooled infrared imaging technology based on MEMS has many advantages, such as low cost, small size, producing simple. In addition, the theory proves that the technology's high thermal detection sensitivity. So it has a very broad application prospects in the field of high performance infrared detection. The paper mainly focuses on an image capturing and processing system in the new type of optical-readout uncooled infrared imaging technology based on MEMS. The image capturing and processing system consists of software and hardware. We build our image processing core hardware platform based on TI's high performance DSP chip which is the TMS320DM642, and then design our image capturing board based on the MT9P031. MT9P031 is Micron's company high frame rate, low power consumption CMOS chip. Last we use Intel's company network transceiver devices-LXT971A to design the network output board. The software system is built on the real-time operating system DSP/BIOS. We design our video capture driver program based on TI's class-mini driver and network output program based on the NDK kit for image capturing and processing and transmitting. The experiment shows that the system has the advantages of high capturing resolution and fast processing speed. The speed of the network transmission is up to 100Mbps.

Facilitating telemedicine project sustainability in medically underserved areas: a healthcare provider participant perspective.

PubMed

Paul, David L; McDaniel, Reuben R

2016-04-26

Very few telemedicine projects in medically underserved areas have been sustained over time. This research furthers understanding of telemedicine service sustainability by examining teleconsultation projects from the perspective of healthcare providers. Drivers influencing healthcare providers' continued participation in teleconsultation projects and how projects can be designed to effectively and efficiently address these drivers is examined. Case studies of fourteen teleconsultation projects that were part of two health sciences center (HSC) based telemedicine networks was utilized. Semi-structured interviews of 60 key informants (clinicians, administrators, and IT professionals) involved in teleconsultation projects were the primary data collection method. Two key drivers influenced providers' continued participation. First was severe time constraints. Second was remote site healthcare providers' (RSHCPs) sense of professional isolation. Two design steps to address these were identified. One involved implementing relatively simple technology and process solutions to make participation convenient. The more critical and difficult design step focused on designing teleconsultation projects for collaborative, active learning. This learning empowered participating RSHCPs by leveraging HSC specialists' expertise. In order to increase sustainability the fundamental purpose of teleconsultation projects needs to be re-conceptualized. Doing so requires HSC specialists and RSHCPs to assume new roles and highlights the importance of trust. By implementing these design steps, healthcare delivery in medically underserved areas can be positively impacted.

Validation of the Health-Promoting Lifestyle Profile II for Hispanic male truck drivers in the Southwest.

PubMed

Mullins, Iris L; O'Day, Trish; Kan, Tsz Yin

2013-08-01

The aims of the study were to validate the English and Spanish Versions of the Health-Promoting Lifestyle Profile II (HPLP II) with Hispanic male truck drivers and to determine if there were any differences in drivers' responses based on driving responsibility. The methods included a descriptive correlation design, the HPLP II (English and Spanish versions), and a demographic questionnaire. Fifty-two Hispanic drivers participated in the study. There were no significant differences in long haul and short haul drivers' responses to the HPLP II. Cronbach's alpha for the Spanish version was .97 and the subscales alphas ranged from .74 to .94. The English version alpha was .92 and the subscales ranged from .68 to .84. Findings suggest the subscales of Health Responsibility, Physical Activities, Nutrition, and Spirituality Growth on the HPLP II Spanish and English versions may not adequately assess health-promoting behaviors and cultural influences for the Hispanic male population in the southwestern border region.

Development of an errorable car-following driver model

NASA Astrophysics Data System (ADS)

Yang, H.-H.; Peng, H.

2010-06-01

An errorable car-following driver model is presented in this paper. An errorable driver model is one that emulates human driver's functions and can generate both nominal (error-free), as well as devious (with error) behaviours. This model was developed for evaluation and design of active safety systems. The car-following data used for developing and validating the model were obtained from a large-scale naturalistic driving database. The stochastic car-following behaviour was first analysed and modelled as a random process. Three error-inducing behaviours were then introduced. First, human perceptual limitation was studied and implemented. Distraction due to non-driving tasks was then identified based on the statistical analysis of the driving data. Finally, time delay of human drivers was estimated through a recursive least-square identification process. By including these three error-inducing behaviours, rear-end collisions with the lead vehicle could occur. The simulated crash rate was found to be similar but somewhat higher than that reported in traffic statistics.

Driver Performance in the Moments Surrounding a Microsleep

PubMed Central

Boyle, Linda Ng; Tippin, Jon; Paul, Amit; Rizzo, Matthew

2009-01-01

This study examined if individuals who are at increased risk for drowsy-driving because of obstructive sleep apnea syndrome (OSAS), have impairments in driving performance in the moments during microsleep episodes as opposed to during periods of wakefulness. Twenty-four licensed drivers diagnosed with OSAS based on standard clinical and polysomnographic criteria, participated in an hour-long drive in a high-fidelity driving simulator with synchronous electroencephalographic (EEG) recordings for identification of microsleeps. The drivers showed significant deterioration in vehicle control during the microsleep episodes compared to driving performance in the absence of microsleeps on equivalent segments of roadway. The degree of performance decrement correlated with microsleep duration, particularly on curved roads. Results indicate that driving performance deteriorates during microsleep episodes. Detecting microsleeps in real-time and identifying how these episodes of transition between wakefulness and sleep impair driver performance is relevant to the design and implementation of countermeasures such as drowsy driver detection and alerting systems that use EEG technology. PMID:20090864

Contributory fault and level of personal injury to drivers involved in head-on collisions: Application of copula-based bivariate ordinal models.

PubMed

Wali, Behram; Khattak, Asad J; Xu, Jingjing

2018-01-01

The main objective of this study is to simultaneously investigate the degree of injury severity sustained by drivers involved in head-on collisions with respect to fault status designation. This is complicated to answer due to many issues, one of which is the potential presence of correlation between injury outcomes of drivers involved in the same head-on collision. To address this concern, we present seemingly unrelated bivariate ordered response models by analyzing the joint injury severity probability distribution of at-fault and not-at-fault drivers. Moreover, the assumption of bivariate normality of residuals and the linear form of stochastic dependence implied by such models may be unduly restrictive. To test this, Archimedean copula structures and normal mixture marginals are integrated into the joint estimation framework, which can characterize complex forms of stochastic dependencies and non-normality in residual terms. The models are estimated using 2013 Virginia police reported two-vehicle head-on collision data, where exactly one driver is at-fault. The results suggest that both at-fault and not-at-fault drivers sustained serious/fatal injuries in 8% of crashes, whereas, in 4% of the cases, the not-at-fault driver sustained a serious/fatal injury with no injury to the at-fault driver at all. Furthermore, if the at-fault driver is fatigued, apparently asleep, or has been drinking the not-at-fault driver is more likely to sustain a severe/fatal injury, controlling for other factors and potential correlations between the injury outcomes. While not-at-fault vehicle speed affects injury severity of at-fault driver, the effect is smaller than the effect of at-fault vehicle speed on at-fault injury outcome. Contrarily, and importantly, the effect of at-fault vehicle speed on injury severity of not-at-fault driver is almost equal to the effect of not-at-fault vehicle speed on injury outcome of not-at-fault driver. Compared to traditional ordered probability models, the study provides evidence that copula based bivariate models can provide more reliable estimates and richer insights. Practical implications of the results are discussed. Published by Elsevier Ltd.

[Development and evaluation of a small group-based cardiocerebrovascular disease prevention education program for male bus drivers].

PubMed

Kim, Eun Young; Hwang, Seon Young

2012-06-01

This study was conducted to examine effects of a small group-based cardiocerebrovascular disease (CVD) prevention education program on knowledge, stage of change and health behavior among male bus drivers with CVD risk factors. A non-equivalent control group pretest-posttest design was used. Participants were 68 male bus drivers recruited from two urban bus companies. Participants from the two groups were selected by matching age, education and risk factors. Experimental group (n=34) received a small group-based CVD prevention education program 8 times over 6 weeks and 3 times through telephone interviews at 2-week intervals. Data were collected between December, 2010 and March, 2011, and were analyzed using chi-square test, t-test, and repeated measure analysis of variance with SPSS/Win18.0. Experimental group showed significantly higher scores in CVD prevention knowledge (p<.001) and health behavior (p<.001) at 6 and 12 weeks after intervention. Participants in pre-contemplation and contemplation stages made progress to contemplation and action. This was significantly better at 6 and 12 weeks after intervention (p<.001). Results suggest that small group-based education programs for CVD prevention are effective in increasing knowledge, stage of change, and health behavior to prevent CVD among male bus drivers with CVD risk.

Predicting drowsy driving in real-time situations: Using an advanced driving simulator, accelerated failure time model, and virtual location-based services.

PubMed

Wang, Junhua; Sun, Shuaiyi; Fang, Shouen; Fu, Ting; Stipancic, Joshua

2017-02-01

This paper aims to both identify the factors affecting driver drowsiness and to develop a real-time drowsy driving probability model based on virtual Location-Based Services (LBS) data obtained using a driving simulator. A driving simulation experiment was designed and conducted using 32 participant drivers. Collected data included the continuous driving time before detection of drowsiness and virtual LBS data related to temperature, time of day, lane width, average travel speed, driving time in heavy traffic, and driving time on different roadway types. Demographic information, such as nap habit, age, gender, and driving experience was also collected through questionnaires distributed to the participants. An Accelerated Failure Time (AFT) model was developed to estimate the driving time before detection of drowsiness. The results of the AFT model showed driving time before drowsiness was longer during the day than at night, and was longer at lower temperatures. Additionally, drivers who identified as having a nap habit were more vulnerable to drowsiness. Generally, higher average travel speeds were correlated to a higher risk of drowsy driving, as were longer periods of low-speed driving in traffic jam conditions. Considering different road types, drivers felt drowsy more quickly on freeways compared to other facilities. The proposed model provides a better understanding of how driver drowsiness is influenced by different environmental and demographic factors. The model can be used to provide real-time data for the LBS-based drowsy driving warning system, improving past methods based only on a fixed driving. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inhibition of Return and Object-Based Attentional Selection

ERIC Educational Resources Information Center

List, Alexandra; Robertson, Lynn C.

2007-01-01

Visual attention research has revealed that attentional allocation can occur in space- and/or object-based coordinates. Using the direct and elegant design of R. Egly, J. Driver, and R. Rafal (1994), the present experiments tested whether space- and object-based inhibition of return (IOR) emerge under similar time courses. The experiments were…

49 CFR Appendix B to Part 236 - Risk Assessment Criteria

Code of Federal Regulations, 2010 CFR

2010-10-01

... results of the application of safety design principles as noted in Appendix C to this part. The MTTHE is... fault/failure analysis must be based on the assessment of the design and implementation of all safety... associated device drivers, as well as historical performance data, analytical methods and experimental safety...

49 CFR Appendix B to Part 236 - Risk Assessment Criteria

Code of Federal Regulations, 2013 CFR

2013-10-01

... results of the application of safety design principles as noted in Appendix C to this part. The MTTHE is... fault/failure analysis must be based on the assessment of the design and implementation of all safety... associated device drivers, as well as historical performance data, analytical methods and experimental safety...

The role of personality traits and driving experience in self-reported risky driving behaviors and accident risk among Chinese drivers.

PubMed

Tao, Da; Zhang, Rui; Qu, Xingda

2017-02-01

The purpose of this study was to explore the role of personality traits and driving experience in the prediction of risky driving behaviors and accident risk among Chinese population. A convenience sample of drivers (n=511; mean (SD) age=34.2 (8.8) years) completed a self-report questionnaire that was designed based on validated scales for measuring personality traits, risky driving behaviors and self-reported accident risk. Results from structural equation modeling analysis demonstrated that the data fit well with our theoretical model. While showing no direct effects on accident risk, personality traits had direct effects on risky driving behaviors, and yielded indirect effects on accident risk mediated by risky driving behaviors. Both driving experience and risky driving behaviors directly predicted accident risk and accounted for 15% of its variance. There was little gender difference in personality traits, risky driving behaviors and accident risk. The findings emphasized the importance of personality traits and driving experience in the understanding of risky driving behaviors and accident risk among Chinese drivers and provided new insight into the design of evidence-based driving education and accident prevention interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Acquisition of business intelligence from human experience in route planning

NASA Astrophysics Data System (ADS)

Bello Orgaz, Gema; Barrero, David F.; R-Moreno, María D.; Camacho, David

2015-04-01

The logistic sector raises a number of highly challenging problems. Probably one of the most important ones is the shipping planning, i.e. plan the routes that the shippers have to follow to deliver the goods. In this article, we present an artificial intelligence-based solution that has been designed to help a logistic company to improve its routes planning process. In order to achieve this goal, the solution uses the knowledge acquired by the company drivers to propose optimised routes. Hence, the proposed solution gathers the experience of the drivers, processes it and optimises the delivery process. The solution uses data mining to extract knowledge from the company information systems and prepares it for analysis with a case-based reasoning (CBR) algorithm. The CBR obtains critical business intelligence knowledge from the drivers experience that is needed by the planner. The design of the routes is done by a genetic algorithm that, given the processed information, optimises the routes following several objectives, such as minimise the distance or time. Experimentation shows that the proposed approach is able to find routes that improve, on average, the routes made by the human experts.

How to assess driver's interaction with partially automated driving systems - A framework for early concept assessment.

PubMed

van den Beukel, Arie P; van der Voort, Mascha C

2017-03-01

The introduction of partially automated driving systems changes the driving task into supervising the automation with an occasional need to intervene. To develop interface solutions that adequately support drivers in this new role, this study proposes and evaluates an assessment framework that allows designers to evaluate driver-support within relevant real-world scenarios. Aspects identified as requiring assessment in terms of driver-support within the proposed framework are Accident Avoidance, gained Situation Awareness (SA) and Concept Acceptance. Measurement techniques selected to operationalise these aspects and the associated framework are pilot-tested with twenty-four participants in a driving simulator experiment. The objective of the test is to determine the reliability of the applied measurements for the assessment of the framework and whether the proposed framework is effective in predicting the level of support offered by the concepts. Based on the congruency between measurement scores produced in the test and scores with predefined differences in concept-support, this study demonstrates the framework's reliability. A remaining concern is the framework's weak sensitivity to small differences in offered support. The article concludes that applying the framework is especially advantageous for evaluating early design phases and can successfully contribute to the efficient development of driver's in-control and safe means of operating partially automated vehicles. Copyright © 2016 Elsevier Ltd. All rights reserved.

The American Medical Association Older Driver Curriculum for health professionals: changes in trainee confidence, attitudes, and practice behavior.

PubMed

Meuser, Thomas M; Carr, David B; Irmiter, Cheryl; Schwartzberg, Joanne G; Ulfarsson, Gudmundur F

2010-01-01

Few gerontology and geriatrics professionals receive training in driver fitness evaluation, state reporting of unfit drivers, or transportation mobility planning yet are often asked to address these concerns in the provision of care to older adults. The American Medical Association (AMA) developed an evidence-based, multi-media Curriculum to promote basic competences. This study evaluated reported changes in practice behaviors 3 months posttraining in 693 professionals trained via the AMA approach. Eight Teaching Teams, designated and trained by AMA staff, offered 22 training sessions across the United States in 2006 to 2007. Trainees (67% female; mean age 46) completed a pretest questionnaire and a posttest administered by mail. Physicians were the largest professional group (32%). Although many trainees acknowledged having conversations with patients about driving at pretest, few endorsed utilizing specific techniques recommended by the AMA prior to this training. The posttest response rate was 34% (n = 235). Significant improvements in reported attitudes, confidence, and practices were found across measured items. In particular, posttest data indicated new adoption of in-office screening techniques, chart documentation of driver safety concerns, and transportation alternative planning strategies. Findings suggest that a well-designed, one-time continuing education intervention can enhance health professional confidence and clinical practice concerning driver fitness evaluation and mobility planning. Targeted dissemination of this Curriculum (in-person and online) will allow more to benefit in the future.

A novel estimating method for steering efficiency of the driver with electromyography signals

NASA Astrophysics Data System (ADS)

Liu, Yahui; Ji, Xuewu; Hayama, Ryouhei; Mizuno, Takahiro

2014-05-01

The existing research of steering efficiency mainly focuses on the mechanism efficiency of steering system, aiming at designing and optimizing the mechanism of steering system. In the development of assist steering system especially the evaluation of its comfort, the steering efficiency of driver physiological output usually are not considered, because this physiological output is difficult to measure or to estimate, and the objective evaluation of steering comfort therefore cannot be conducted with movement efficiency perspective. In order to take a further step to the objective evaluation of steering comfort, an estimating method for the steering efficiency of the driver was developed based on the research of the relationship between the steering force and muscle activity. First, the steering forces in the steering wheel plane and the electromyography (EMG) signals of the primary muscles were measured. These primary muscles are the muscles in shoulder and upper arm which mainly produced the steering torque, and their functions in steering maneuver were identified previously. Next, based on the multiple regressions of the steering force and EMG signals, both the effective steering force and the total force capacity of driver in steering maneuver were calculated. Finally, the steering efficiency of driver was estimated by means of the estimated effective force and the total force capacity, which represented the information of driver physiological output of the primary muscles. This research develops a novel estimating method for driver steering efficiency of driver physiological output, including the estimation of both steering force and the force capacity of primary muscles with EMG signals, and will benefit to evaluate the steering comfort with an objective perspective.

Teaching Driver Education Technology to Novice Drivers.

ERIC Educational Resources Information Center

Young, Anthony

A cybernetic unit in driver education was developed to help grade 10 students develop the skills needed to acquire and process driver education information and prepare for the driving phase of driver education in grade 11. Students used a simulator to engage in a series of scenarios designed to promote development of social, behavioral, and mental…

78 FR 76392 - Hours of Service of Drivers: Application for Exemption; David Muresan

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-17

...-0047] Hours of Service of Drivers: Application for Exemption; David Muresan AGENCY: Federal Motor... of service (HOS) rules. Mr. Muresan is a long-haul truck driver who teams with a second driver in... co-driver be permitted to operate under HOS rules that he has designed. He believes that his...

OSIRIS and SOMBRERO Inertial Fusion Power Plant Designs, Volume 2: Designs, Assessments, and Comparisons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meier, W. R.; Bieri, R. L.; Monsler, M. J.

1992-03-01

This is a comprehensive design study of two Inertial Fusion Energy (IFE) electric power plants. Conceptual designs are presented for a fusion reactor (called Osiris) using an induction-linac heavy-ion beam driver, and another (called SOMBRERO) using a KrF laser driver. The designs covered all aspects of IFE power plants, including the chambers, heat transport and power conversion systems, balance-of-plant facilities, target fabrication, target injection and tracking, as well as the heavy-ion and KrF drivers. The point designs were assessed and compared in terms of their environmental & safety aspects, reliability and availability, economics, and technology development needs.

Calibration of the inertial consistency index to assess road safety on horizontal curves of two-lane rural roads.

PubMed

Llopis-Castelló, David; Camacho-Torregrosa, Francisco Javier; García, Alfredo

2018-05-26

One of every four road fatalities occurs on horizontal curves of two-lane rural roads. To this regard, many studies have been undertaken to analyze the crash risk on this road element. Most of them were based on the concept of geometric design consistency, which can be defined as how drivers' expectancies and road behavior relate. However, none of these studies included a variable which represents and estimates drivers' expectancies. This research presents a new local consistency model based on the Inertial Consistency Index (ICI). This consistency parameter is defined as the difference between the inertial operating speed, which represents drivers' expectations, and the operating speed, which represents road behavior. The inertial operating speed was defined as the weighted average operating speed of the preceding road section. In this way, different lengths, periods of time, and weighting distributions were studied to identify how the inertial operating speed should be calculated. As a result, drivers' expectancies should be estimated considering 15 s along the segment and a linear weighting distribution. This was consistent with drivers' expectancies acquirement process, which is closely related to Short-Term Memory. A Safety Performance Function was proposed to predict the number of crashes on a horizontal curve and consistency thresholds were defined based on the ICI. To this regard, the crash rate increased as the ICI increased. Finally, the proposed consistency model was compared with previous models. As a conclusion, the new Inertial Consistency Index allowed a more accurate estimation of the number of crashes and a better assessment of the consistency level on horizontal curves. Therefore, highway engineers have a new tool to identify where road crashes are more likely to occur during the design stage of both new two-lane rural roads and improvements of existing highways. Copyright © 2018 Elsevier Ltd. All rights reserved.

Alternative design consistency rating methods for two-lane rural highways

DOT National Transportation Integrated Search

2000-08-01

Design consistency refers to the conformance of a highway's geometry with driver expectancy. Drivers make fewer errors in the vicinity of geometric features that conform with their expectations. Techniques to evaluate the consistency of a design docu...

Effect of directional speech warnings on road hazard detection.

PubMed

Serrano, Jesús; Di Stasi, Leandro L; Megías, Alberto; Catena, Andrés

2011-12-01

In the last 2 decades, cognitive science and the transportation psychology field have dedicated a lot of effort to designing advanced driver support systems. Verbal warning systems are increasingly being implemented in modern automobiles in an effort to increase road safety. The study presented here investigated the impact of directional speech alert messages on the participants' speed to judge whether or not naturalistic road scenes depicted a situation of impending danger. Thirty-eight volunteers performed a computer-based key-press reaction time task. Findings indicated that semantic content of verbal warning signals can be used for increasing driving safety and improving hazard detection. Furthermore, the classical result regarding signal accuracy is confirmed: directional informative speech messages lead to faster hazard detection compared to drivers who received a high rate of false alarms. Notwithstanding some study limitations (lack of driver experience and low ecological validity), this evidence could provide important information for the specification of future Human-Machine-interaction (HMI) design guidelines.

The Effects of Vehicle Redesign on the Risk of Driver Death.

PubMed

Farmer, Charles M; Lund, Adrian K

2015-01-01

This study updates a 2006 report that estimated the historical effects of vehicle design changes on driver fatality rates in the United States, separate from the effects of environmental and driver behavior changes during the same period. In addition to extending the period covered by 8 years, this study estimated the effect of design changes by model year and vehicle type. Driver death rates for consecutive model years of vehicle models without design changes were used to estimate the vehicle aging effect and the death rates that would have been expected if the entire fleet had remained unchanged from the 1985 calendar year. These calendar year estimates are taken to be the combined effect of road environment and motorist behavioral changes, with the difference between them and the actual calendar year driver fatality rates reflecting the effect of changes in vehicle design and distribution of vehicle types. The effects of vehicle design changes by model year were estimated for cars, SUVs, and pickups by computing driver death rates for model years 1984-2009 during each of their first 3 full calendar years of exposure and comparing with the expected rates if there had been no design changes. As reported in the 2006 study, had there been no changes in the vehicle fleet, driver death risk would have declined during calendar years 1985-1993 and then slowly increased from 1993 to 2004. The updated results indicate that the gradual increase would have continued through 2006, after which driver fatality rates again would have declined through 2012. Overall, it is estimated that there were 7,700 fewer driver deaths in 2012 than there would have been had vehicle designs not changed. Cars were the first vehicle type whose design safety generally exceeded that of the 1984 model year (starting in model year 1996), followed by SUVs (1998 models) and pickups (2002 models). By the 2009 model year, car driver fatality risk had declined 51% from its high in 1994, pickup driver fatality risk had declined 61% from its high in 1988, and SUV risk had declined 79% from its high in 1988. The risk of driver death in 2009 model passenger vehicles was 8% lower than that in 2008 models and about half that in 1984 models. Changes in vehicles, whether from government regulations and consumer testing that led to advanced safety designs or from other factors such as consumer demand for different sizes and types of vehicles, have been key contributors to the decline in U.S. motor vehicle occupant crash death rates since the mid-1990s. Since the early 1990s, environmental and behavioral risk factors have not shown similar improvement, until the recession of 2007, even though there are many empirically proven countermeasures that have been inadequately applied.

Heavy ion driven LMF design concept

NASA Astrophysics Data System (ADS)

Lee, E. P.

1991-08-01

The US Department of Energy has conducted a multi-year study of the requirements, designs and costs for a Laboratory Microfusion Facility (LMF). The primary purpose of the LMF would be testing of weapons physics and effects simulation using the output from microexplosions of inertial fusion pellets. It does not need a high repetition rate, efficient driver system as required by an electrical generating plant. However there would be so many features in common that the design, construction and operation of an LMF would considerably advance the application of inertial confinement fusion to energy production. The DOE study has concentrated particularly on the LMF driver, with design and component development undertaken at several national laboratories. Principally, these are LLNL (Solid State Laser), LANL (Gas Laser), and SNLA (Light Ions). Heavy Ions, although considered a possible LMF driver did not receive attention until the final stages of this study since its program management was through the Office of Energy Research rather than Defense Programs. During preparation of a summary report for the study it was decided that some account of heavy ions was needed for a complete survey of the driver candidates. A conceptual heavy ion LMF driver design was created for the DOE report which is titled LMC Phase II Design Concepts. The heavy ion driver did not receive the level of scrutiny of the other concepts and, unlike the others, no costs analysis by an independent contractor was performed. Since much of heavy ion driver design lore was brought together in this exercise it is worthwhile to make it available as an independent report. This is reproduced here as it appears in the DOE report.

IIHS side crash test ratings and occupant death risk in real-world crashes.

PubMed

Teoh, Eric R; Lund, Adrian K

2011-10-01

To evaluate how well the Insurance Institute for Highway Safety (IIHS) side crash test ratings predict real-world occupant death risk in side-impact crashes. The IIHS has been evaluating passenger vehicle side crashworthiness since 2003. In the IIHS side crash test, a vehicle is impacted perpendicularly on the driver's side by a moving deformable barrier simulating a typical sport utility vehicle (SUV) or pickup. Injury ratings are computed for the head/neck, torso, and pelvis/leg, and vehicles are rated based on their ability to protect occupants' heads and resist occupant compartment intrusion. Component ratings are combined into an overall rating of good, acceptable, marginal, or poor. A driver-only rating was recalculated by omitting rear passenger dummy data. Data were extracted from the Fatality Analysis Reporting System (FARS) and National Automotive Sampling System/General Estimates System (NASS/GES) for the years 2000-2009. Analyses were restricted to vehicles with driver side air bags with head and torso protection as standard features. The risk of driver death was computed as the number of drivers killed (FARS) divided by the number involved (NASS/GES) in left-side impacts and was modeled using logistic regression to control for the effects of driver age and gender and vehicle type and curb weight. Death rates per million registered vehicle years were computed for all outboard occupants and compared by overall rating. Based on the driver-only rating, drivers of vehicles rated good were 70 percent less likely to die when involved in left-side crashes than drivers of vehicles rated poor, after controlling for driver and vehicle factors. Compared with vehicles rated poor, driver death risk was 64 percent lower for vehicles rated acceptable and 49 percent lower for vehicles rated marginal. All 3 results were statistically significant. Among components, vehicle structure rating exhibited the strongest relationship with driver death risk. The vehicle registration-based results for drivers were similar, suggesting that the benefit was not due to differences in crash risk. The same pattern of results held for outboard occupants in nearside crashes per million registered vehicle years and, with the exception of marginally rated vehicles, also held for other crash types. Results show that IIHS side crash test ratings encourage designs that improve crash protection in meaningful ways beyond encouraging head protection side air bags, particularly by promoting vehicle structures that limit occupant compartment intrusion. Results further highlight the need for a strong occupant compartment and its influence in all types of crashes.

Preliminary design approach for large high precision segmented reflectors

NASA Technical Reports Server (NTRS)

Mikulas, Martin M., Jr.; Collins, Timothy J.; Hedgepeth, John M.

1990-01-01

A simplified preliminary design capability for erectable precision segmented reflectors is presented. This design capability permits a rapid assessment of a wide range of reflector parameters as well as new structural concepts and materials. The preliminary design approach was applied to a range of precision reflectors from 10 meters to 100 meters in diameter while considering standard design drivers. The design drivers considered were: weight, fundamental frequency, launch packaging volume, part count, and on-orbit assembly time. For the range of parameters considered, on-orbit assembly time was identified as the major design driver. A family of modular panels is introduced which can significantly reduce the number of reflector parts and the on-orbit assembly time.

Static Anthropometric Characteristics of Bangladeshi Vehicle Driver: A Case Study

PubMed Central

Sarker, E.

2016-01-01

Background. Inappropriate design of sitting furniture and working equipment causes the serious musculoskeletal injuries and various pains as well as reducing working efficiency. Uncomfortable sitting posture in prolonged driving in Bangladesh is an issue to be solved immediately. Therefore, anthropometric databank of user population is significantly essential for the suitable dimensional design for avoiding these remarkable problems. Methods. This study analyses the anthropometric data of the Bangladeshi male vehicle driver aged between 30 and 60 years. A total of 210 Bangladeshi healthy drivers are considered for 15 anthropometric measurements and compared with the similar anthropometrics of other nationalities. Results. The mean stature and sitting height erect of Bangladeshi driver are 1645 mm and 843 mm, respectively. The mean of body mass index (BMI) of the drivers is 26.09 kg/m2, which indicates that the drivers are overweight. The mean stature of Bangladeshi driver is 17 mm shorter than the driver of Korea and 115 mm shorter than the driver of Iran. Conclusion. There are substantial differences between the body dimensions of Bangladeshi driver and similar dimensions of other countries. In comparison, Bangladeshi driver is found to be the shortest compared with the sample of other nationalities. PMID:27579216

The Alabama VIP older driver study rationale and design: examining the relationship between vision impairment and driving using naturalistic driving techniques.

PubMed

Owsley, Cynthia; McGwin, Gerald; Antin, Jonathan F; Wood, Joanne M; Elgin, Jennifer

2018-02-07

Older drivers aged ≥70 years old have among the highest rates of motor vehicle collisions (MVC) compared to other age groups. Driving is a highly visual task, and older adults have a high prevalence of vision impairment compared to other ages. Most studies addressing visual risk factors for MVCs by older drivers utilize vehicle accident reports as the primary outcome, an approach with several methodological limitations. Naturalistic driving research methods overcome these challenges and involve installing a high-tech, unobtrusive data acquisition system (DAS) in an older driver's own vehicle. The DAS continuously records multi-channel video of driver and roadway, sensor-based kinematics, GPS location, and presence of nearby objects in front of the vehicle, providing an objective measure of driving exposure. In this naturalistic driving study, the purpose is to examine the relationship between vision and crashes and near-crashes, lane-keeping, turning at intersections, driving performance during secondary tasks demands, and the role of front-seat passengers. An additional aim is to compare results of the on-road driving evaluation by a certified driving rehabilitation specialist to objective indicators of driving performance derived from the naturalistic data. Drivers ≥70 years old are recruited from ophthalmology clinics and a previous population-based study of older drivers, with the goal of recruiting persons with wide ranging visual function. Target samples size is 195 drivers. At a baseline visit, the DAS is installed in the participant's vehicle and a battery of health and functional assessments are administered to the driver including visual-sensory and visual-cognitive tests. The DAS remains installed in the vehicle for six months while the participant goes about his/her normal driving with no imposed study restrictions. After six months, the driver returns for DAS de-installation, repeat vision testing, and an on-road driving evaluation by a certified driving rehabilitation specialist (CDRS). The data streams recorded by the DAS are uploaded to the data coordinating center for analysis. The Alabama VIP Older Driver Study is the first naturalistic older driver study specifically focused on the enrollment of drivers with vision impairment in order to study the relationship between visual dysfunction and driver safety and performance.

Crash probability estimation via quantifying driver hazard perception.

PubMed

Li, Yang; Zheng, Yang; Wang, Jianqiang; Kodaka, Kenji; Li, Keqiang

2018-07-01

Crash probability estimation is an important method to predict the potential reduction of crash probability contributed by forward collision avoidance technologies (FCATs). In this study, we propose a practical approach to estimate crash probability, which combines a field operational test and numerical simulations of a typical rear-end crash model. To consider driver hazard perception characteristics, we define a novel hazard perception measure, called as driver risk response time, by considering both time-to-collision (TTC) and driver braking response to impending collision risk in a near-crash scenario. Also, we establish a driving database under mixed Chinese traffic conditions based on a CMBS (Collision Mitigation Braking Systems)-equipped vehicle. Applying the crash probability estimation in this database, we estimate the potential decrease in crash probability owing to use of CMBS. A comparison of the results with CMBS on and off shows a 13.7% reduction of crash probability in a typical rear-end near-crash scenario with a one-second delay of driver's braking response. These results indicate that CMBS is positive in collision prevention, especially in the case of inattentive drivers or ole drivers. The proposed crash probability estimation offers a practical way for evaluating the safety benefits in the design and testing of FCATs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dynamic high-speed acquisition system design of transmission error with USB based on LabVIEW and FPGA

NASA Astrophysics Data System (ADS)

Zheng, Yong; Chen, Yan

2013-10-01

To realize the design of dynamic acquisition system for real-time detection of transmission chain error is very important to improve the machining accuracy of machine tool. In this paper, the USB controller and FPGA is used for hardware platform design, combined with LabVIEW to design user applications, NI-VISA is taken for develop USB drivers, and ultimately achieve the dynamic acquisition system design of transmission error

A 10 Gb/s laser driver in 130 nm CMOS technology for high energy physics applications

DOE PAGES

Zhang, T.; Tavernier, F.; Moreira, P.; ...

2015-02-19

The GigaBit Laser Driver (GBLD) is a key on-detector component of the GigaBit Transceiver (GBT) system at the transmitter side. We have developed a 10 Gb/s GBLD (GBLD10) in a 130 nm CMOS technology, as part of the design efforts towards the upgrade of the electrical components of the LHC experiments. The GBLD10 is based on the distributed-amplifier (DA) architecture and achieves data rates up to 10 Gb/s. It is capable of driving VCSELs with modulation currents up to 12 mA. Furthermore, a pre-emphasis function has been included in the proposed laser driver in order to compensate for the capacitivemore » load and channel losses.« less

Driver-Array Based Flat-Panel Loudspeakers: Theoretical Background and Design Guidelines

NASA Astrophysics Data System (ADS)

Anderson, David Allan

This thesis relates to the simulation and design of flat-panel loudspeakers using moving-coil driver elements. A brief history of the industry is given, including a collection of products and patents from 1925 until the present, an overview of research papers, and a discussion of current products available. The mechanics of bending flat panels are developed with respect to localized driving forces, both in the frequency domain and the time domain as an impulse response. These simulations are compared to measurements on prototype panels. Additional resonant elements influence the behavior of the system: an optional ported rear enclosure and the resonant characteristics of the drivers. The governing equations for these systems are derived and solutions are implemented using equivalent mechanical circuits and numerical methods. The idea of using driver arrays to independently actuate modes of the panel is discussed at length with respect to modal addressability, modal spillover, and experimental validation. The numerical approach to determining the optimal driver placement for a given set of modes is derived and experimentally validated. An investigation of the acoustic behavior of flat panel loudspeakers is presented, using mechanical simulation results to predict the acoustic radiation. The simulations are compared to measurements and found to accurately predict important mechanical and acoustical behaviors. It is demonstrated that a driver array, with the proper biasing, is capable of creating a flat panel loudspeaker which acts more like a piston than a "diffuse radiator" flat panel loudspeaker. The techniques of "Modal Crossover Networks" are introduced, which use multi-band filters to bias the driver array differently for different frequency bands, optimized for audio reproduction. The question of how many drivers are necessary for a modal crossover network is addressed and found to be dependent on the estimated quality factor (Q) of the panel material and edge conditions.

An installed nacelle design code using a multiblock Euler solver. Volume 1: Theory document

NASA Technical Reports Server (NTRS)

Chen, H. C.

1992-01-01

An efficient multiblock Euler design code was developed for designing a nacelle installed on geometrically complex airplane configurations. This approach employed a design driver based on a direct iterative surface curvature method developed at LaRC. A general multiblock Euler flow solver was used for computing flow around complex geometries. The flow solver used a finite-volume formulation with explicit time-stepping to solve the Euler Equations. It used a multiblock version of the multigrid method to accelerate the convergence of the calculations. The design driver successively updated the surface geometry to reduce the difference between the computed and target pressure distributions. In the flow solver, the change in surface geometry was simulated by applying surface transpiration boundary conditions to avoid repeated grid generation during design iterations. Smoothness of the designed surface was ensured by alternate application of streamwise and circumferential smoothings. The capability and efficiency of the code was demonstrated through the design of both an isolated nacelle and an installed nacelle at various flow conditions. Information on the execution of the computer program is provided in volume 2.

Perception and biodynamics in unalerted precrash response.

PubMed

McGehee, Daniel V; Carsten, Oliver M J

2010-01-01

This research seeks to better understand unalerted driver response just prior to a serious vehicle crash. Few studies have been able to view a crash from the inside-with a camera focused on the driver and occupants. Four studies are examined: 1) a high-fidelity simulator study with an unalerted intersection incursion crash among 107 drivers; 2) four crashes from the Virginia Tech Transportation Institute (VTTI) 100 car study; 3) 58 crashes from vehicles equipped with an event triggered video recorder; and 4) a custom-designed high-fidelity simulator experiment that examined unalerted driver response to a head-on crash with a heavy truck. Analyses concentrate on decomposing driver perception, action, facial and postural changes with a focus on describing the neurophysiologic mechanisms designed to respond to danger. Results indicate that drivers involved in severe crashes generally have preview that an impact is about to occur. They respond first with vehicle control inputs (accelerator pedal release) along with facial state changes and withdrawal of the head back towards the head restraint. These responses frequently occur almost simultaneously, providing safety system designers with a number of reliable driver performance measures to monitor. Understanding such mechanisms may assist future advanced driver assistance systems (ADAS), advanced restraints, model development of advanced anthropomorphic test dummies (ATDs), injury prediction and the integration of active and passive safety systems.

Indigenous Manufacturing realization of TWIN Source

NASA Astrophysics Data System (ADS)

Pandey, R.; Bandyopadhyay, M.; Parmar, D.; Yadav, R.; Tyagi, H.; Soni, J.; Shishangiya, H.; Sudhir Kumar, D.; Shah, S.; Bansal, G.; Pandya, K.; Parmar, K.; Vuppugalla, M.; Gahlaut, A.; Chakraborty, A.

2017-04-01

TWIN source is two RF driver based negative ion source that has been planned to bridge the gap between single driver based ROBIN source (currently operational) and eight river based DNB source (to be operated under IN-TF test facility). TWIN source experiments have been planned at IPR keeping the objective of long term domestic fusion programme to gain operational experiences on vacuum immersed multi driver RF based negative ion source. High vacuum compatible components of twin source are designed at IPR keeping an aim on indigenous built in attempt. These components of TWIN source are mainly stainless steel and OFC-Cu. Being high heat flux receiving components, one of the major functional requirements is continuous heat removal via water as cooling medium. Hence for the purpose stainless steel parts are provided with externally milled cooling lines and that shall be covered with a layer of OFC-cu which would be on the receiving side of high heat flux. Manufacturability of twin source components requires joining of these dissimilar materials via process like electrode position, electron beam welding and vacuum brazing. Any of these manufacturing processes shall give a vacuum tight joint having proper joint strength at operating temperature and pressure. Taking the indigenous development effort vacuum brazing (in non-nuclear environment) has been opted for joining of dissimilar materials of twin source being one of the most reliable joining techniques and commercially feasible across the suppliers of country. Manufacturing design improvisation for the components has been done to suit the vacuum brazing process requirement and to ease some of the machining without comprising over the functional and operational requirements. This paper illustrates the details on the indigenous development effort, design improvisation to suits manufacturability, vacuum brazing basics and its procedures for twin source components.

Performance of an Additional Task During Level 2 Automated Driving: An On-Road Study Comparing Drivers With and Without Experience With Partial Automation.

PubMed

Solís-Marcos, Ignacio; Ahlström, Christer; Kircher, Katja

2018-05-01

To investigate the influence of prior experience with Level 2 automation on additional task performance during manual and Level 2 partially automated driving. Level 2 automation is now on the market, but its effects on driver behavior remain unclear. Based on previous studies, we could expect an increase in drivers' engagement in secondary tasks during Level 2 automated driving, but it is yet unknown how drivers will integrate all the ongoing demands in such situations. Twenty-one drivers (12 without, 9 with Level 2 automation experience) drove on a highway manually and with Level 2 automation (exemplified by Volvo Pilot Assist generation 2; PA2) while performing an additional task. In half of the conditions, the task could be interrupted (self-paced), and in the other half, it could not (system-paced). Drivers' visual attention, additional task performance, and other compensatory strategies were analyzed. Driving with PA2 led to decreased scores in the additional task and more visual attention to the dashboard. In the self-paced condition, all drivers looked more to the task and perceived a lower mental demand. The drivers experienced with PA2 used the system and the task more than the novice group and performed more overtakings. The additional task interfered more with Level 2 automation than with manual driving. The drivers, particularly the automation novice drivers, used some compensatory strategies. Automation designers need to consider these potential effects in the development of future automated systems.

Landscape-based upstream-downstream prevalence of land-use/cover change drivers in southeastern rift escarpment of Ethiopia.

PubMed

Temesgen, Habtamu; Wu, Wei; Legesse, Abiyot; Yirsaw, Eshetu; Bekele, Belew

2018-02-23

Characterized by high population density on a rugged topography, the Gedeo-Abaya landscape dominantly contains a multi-strata traditional agroforests showing the insight of Gedeo farmers on natural resource management practices. Currently, this area has been losing its resilience and is becoming unable to sustain its inhabitants. Based on both RS-derived and GIS-computed land-use/cover changes (LUCC) as well as socioeconomic validations, this article explored the LUCC and agroecological-based driver patterns in Gedeo-Abaya landscape from 1986 to 2015. A combination of geo-spatial technology and cross-sectional survey design were employed to detect the drivers behind these changes. The article discussed that LUCC and the prevalence of drivers are highly diverse and vary throughout agroecological zones. Except for the population, most downstream top drivers are perceived as insignificant in the upstream region and vice versa. In the downstream, land-use/cover (LUC) classes are more dynamic, diverse, and challenged by nearly all anticipated drivers than are upstream ones. Agroforestry LUC has been increasing (by 25% of its initial cover) and is becoming the predominant cover type, although socioeconomic analysis and related findings show its rapid LUC modification. A rapid reduction of woodland/shrubland (63%) occurred in the downstream, while wetland/marshy land increased threefold (158%), from 1986 to 2015 with annual change rates of - 3.7 and + 6%, respectively. Land degradation induced by changes in land use is a serious problem in Africa, especially in the densely populated sub-Saharan regions such as Ethiopia (FAO 2015). Throughout the landscape, LUCC is prominently affecting land-use system of the study landscape due to population pressure in the upstream region and drought/rainfall variability, agribusiness investment, and charcoaling in the downstream that necessitate urgent action.

Preliminary design considerations for 10 to 40 meter-diameter precision truss reflectors

NASA Technical Reports Server (NTRS)

Mikulas, Martin M., Jr.; Collins, Timothy J.; Hedgepeth, John M.

1990-01-01

A simplified preliminary design capability for erectable precision segmented reflectors is presented. This design capability permits a rapid assessment of a wide range of reflector parameters as well as new structural concepts and materials. The preliminary design approach was applied to a range of precision reflectors from 10 meters to 100 meters in diameter while considering standard design drivers. The design drivers considered were: weight, fundamental frequency, launch packaging volume, part count, and on-orbit assembly time. For the range of parameters considered, on-orbit assembly time was identified as the major design driver. A family of modular panels is introduced which can significantly reduce the number of reflector parts and the on-orbit assembly time.

Low power laser driver design in 28nm CMOS for on-chip and chip-to-chip optical interconnect

NASA Astrophysics Data System (ADS)

Belfiore, Guido; Szilagyi, Laszlo; Henker, Ronny; Ellinger, Frank

2015-09-01

This paper discusses the challenges and the trade-offs in the design of laser drivers for very-short distance optical communications. A prototype integrated circuit is designed and fabricated in 28 nm super-low-power CMOS technology. The power consumption of the transmitter is 17.2 mW excluding the VCSEL that in our test has a DC power consumption of 10 mW. The active area of the driver is only 0.0045 mm2. The driver can achieve an error-free (BER < 10 -12) electrical data-rate of 25 Gbit/s using a pseudo random bit sequence of 27 -1. When the driver is connected to the VCSEL module an open optical eye is reported at 15 Gbit/s. In the tested bias point the VCSEL module has a measured bandwidth of 10.7 GHz.

Handbook for designing roadways for the aging population.

DOT National Transportation Integrated Search

2014-06-01

The original Older Driver Highway Design Handbook was published by FHWA in 1998 (FHWA-RD-97-135). The : 2nd edition, titled Highway Design Handbook for Older Drivers and Pedestrians (FHWA-RD-01-103) was published in : 2001. This 3rd edition, under a ...

How to identify the key factors that affect driver perception of accident risk. A comparison between Italian and Spanish driver behavior.

PubMed

de Oña, Juan; de Oña, Rocio; Eboli, Laura; Forciniti, Carmen; Mazzulla, Gabriella

2014-12-01

Road crashes can be caused by different factors, including infrastructure, vehicles, and human variables. Many research studies have focused solely on identifying the key factors that cause road crashes. From these studies, it emerged that human factors have the most relevant impact on accident severity. More specifically, accident severity depends on several factors related directly to the driver, i.e., driving experience, driver's socio-economic characteristics, and driving behavior and attitudes. In this paper, we investigate driver behaviors and attitudes while driving and specifically focus on different methods for identifying the factors that most affect the driver's perception of accident risk. To this end, we designed and conducted a survey in two different European contexts: the city of Cosenza, which is located in the south of Italy, and the city of Granada, which is located in the south of Spain. Samples of drivers were contacted for their opinions on certain aspects of driving rules and attitudes while driving, and different types of questions were addressed to the drivers to assess their judgments of these aspects. Consequently, different methods of data analysis were applied to determine the aspects that heavily influence driver perception of accident risk. An experiment based on the stated preferences (SP) was carried out with the drivers, and the SP data were analyzed using an ordered probit (OP) model. Interesting findings emerged from different analyses of the data and from the comparisons among the data collected in the two different territorial contexts. We found that both Italian and Spanish drivers consider driving in an altered psychophysical state and violating the overtaking rules to be the most risky behaviors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Designing a System for Computer-Assisted Instruction in Road Education: A First Evaluation.

ERIC Educational Resources Information Center

Garcia-Ros, Rafael; Montoro, Luis; Valero, Pedro; Bayarri, Salvador; Martinez, Tomas

1999-01-01

Describes SIVAS, a computer-based system for driver education based on visual simulation that was developed in Spain to support theoretical concepts about driving in driving schools. Explains how teachers can select pre-built scenarios related to driving lessons in order to make up a lecture. (Author/LRW)

A Design Rationale Capture Tool to Support Design Verification and Re-use

NASA Technical Reports Server (NTRS)

Hooey, Becky Lee; Da Silva, Jonny C.; Foyle, David C.

2012-01-01

A design rationale tool (DR tool) was developed to capture design knowledge to support design verification and design knowledge re-use. The design rationale tool captures design drivers and requirements, and documents the design solution including: intent (why it is included in the overall design); features (why it is designed the way it is); information about how the design components support design drivers and requirements; and, design alternatives considered but rejected. For design verification purposes, the tool identifies how specific design requirements were met and instantiated within the final design, and which requirements have not been met. To support design re-use, the tool identifies which design decisions are affected when design drivers and requirements are modified. To validate the design tool, the design knowledge from the Taxiway Navigation and Situation Awareness (T-NASA; Foyle et al., 1996) system was captured and the DR tool was exercised to demonstrate its utility for validation and re-use.

Effectiveness evaluation of simulative workshops for newly licensed drivers.

PubMed

Rosenbloom, Tova; Eldror, Ehud

2014-02-01

The current study set to examine the effects of simulator use in driving instruction on newly licensed drivers, comparing the road safety knowledge and reported intended behavior, as well as the actual driving performance of new drivers. Participants consisted of 280 newly licensed driver, of which 140 whose drivers license training included additional simulator-based lessons, and 140 drivers whose training precluded simulator-based lessons. All drivers answered questionnaires pertaining to their intended safe driving behaviors (according to Ajzen's (2000) theory of planned behavior), and to their traffic safety knowledge. Of the initial sample, 40 drivers received actual driving performance evaluation by an expert driving instructor, as well as by in-vehicle data recorders (IVDRs). We assumed that safer drivers report safer driving intentions, demonstrate greater traffic safety knowledge, evaluated as safer drivers by the driving instructor, and display lower and stable driving parameters on the IVDRs. We hypothesized that theoretical driving studies combined with practical training on simulators will elevate the safety level of novices driving. Hierarchical regression analyses on driving intentions indicated that drivers who did not receive simulator-based lessons demonstrated safer driving intentions compared to drivers who received simulator-based lessons. This pattern possibly indicating the drivers who received simulator-based lessons felt more confident in their driving abilities compared to drivers who did not receive simulated training. No significant difference was found in traffic safety knowledge, or in the evaluation of the expert driving instructor. IDVR data comparisons indicated drivers who received simulator-based lessons braked more often and were less prone to headway events, suggesting a more responsive driving style. These findings do not point to any significant advantage or disadvantage of the current simulator-based driving training over other driving training methods. Copyright © 2013 Elsevier Ltd. All rights reserved.

Intelligent vehicle safety control strategy in various driving situations

NASA Astrophysics Data System (ADS)

Moon, Seungwuk; Cho, Wanki; Yi, Kyongsu

2010-12-01

This paper describes a safety control strategy for intelligent vehicles with the objective of optimally coordinating the throttle, brake, and active front steering actuator inputs to obtain both lateral stability and longitudinal safety. The control system consists of a supervisor, control algorithms, and a coordinator. From the measurement and estimation signals, the supervisor determines the active control modes among normal driving, longitudinal safety, lateral stability, and integrated safety control mode. The control algorithms consist of longitudinal and lateral stability controllers. The longitudinal controller is designed to improve the driver's comfort during normal, safe-driving situations, and to avoid rear-end collision in vehicle-following situations. The lateral stability controller is designed to obtain the required manoeuvrability and to limit the vehicle body's side-slip angle. To obtain both longitudinal safety and lateral stability control in various driving situations, the coordinator optimally determines the throttle, brake, and active front steering inputs based on the current status of the subject vehicle. Closed-loop simulations with the driver-vehicle-controller system are conducted to investigate the performance of the proposed control strategy. From these simulation results, it is shown that the proposed control algorithm assists the driver in combined severe braking/large steering manoeuvring so that the driver can maintain good manoeuvrability and prevent the vehicle from crashing in vehicle-following situations.

A roadmap for interpreting the literature on vision and driving.

PubMed

Owsley, Cynthia; Wood, Joanne M; McGwin, Gerald

2015-01-01

Over the past several decades there has been a sharp increase in the number of studies focused on the relationship between vision and driving. The intensified attention to this topic has most likely been stimulated by the lack of an evidence basis for determining vision standards for driving licensure and a poor understanding about how vision impairment impacts driver safety and performance. Clinicians depend on the literature on vision and driving to advise visually impaired patients appropriately about driving fitness. Policy makers also depend on the scientific literature in order to develop guidelines that are evidence-based and are thus fair to persons who are visually impaired. Thus it is important for clinicians and policy makers alike to understand how various study designs and measurement methods should be interpreted so that the conclusions and recommendations they make are not overly broad, too narrowly constrained, or even misguided. We offer a methodological framework to guide interpretations of studies on vision and driving that can also serve as a heuristic for researchers in the area. Here, we discuss research designs and general measurement methods for the study of vision as they relate to driver safety, driver performance, and driver-centered (self-reported) outcomes. Copyright © 2015 Elsevier Inc. All rights reserved.

Research and Design of Embedded Wireless Meal Ordering System Based on SQLite

NASA Astrophysics Data System (ADS)

Zhang, Jihong; Chen, Xiaoquan

The paper describes features and internal architecture and developing method of SQLite. And then it gives a design and program of meal ordering system. The system realizes the information interaction among the users and embedded devices with SQLite as database system. The embedded database SQLite manages the data and achieves wireless communication by using Bluetooth. A system program based on Qt/Embedded and Linux drivers realizes the local management of environmental data.

Online Detection of Driver Fatigue Using Steering Wheel Angles for Real Driving Conditions.

PubMed

Li, Zuojin; Li, Shengbo Eben; Li, Renjie; Cheng, Bo; Shi, Jinliang

2017-03-02

This paper presents a drowsiness on-line detection system for monitoring driver fatigue level under real driving conditions, based on the data of steering wheel angles (SWA) collected from sensors mounted on the steering lever. The proposed system firstly extracts approximate entropy (ApEn)featuresfromfixedslidingwindowsonreal-timesteeringwheelanglestimeseries. Afterthat, this system linearizes the ApEn features series through an adaptive piecewise linear fitting using a given deviation. Then, the detection system calculates the warping distance between the linear features series of the sample data. Finally, this system uses the warping distance to determine the drowsiness state of the driver according to a designed binary decision classifier. The experimental data were collected from 14.68 h driving under real road conditions, including two fatigue levels: "wake" and "drowsy". The results show that the proposed system is capable of working online with an average 78.01% accuracy, 29.35% false detections of the "awake" state, and 15.15% false detections of the "drowsy" state. The results also confirm that the proposed method based on SWA signal is valuable for applications in preventing traffic accidents caused by driver fatigue.

Online Detection of Driver Fatigue Using Steering Wheel Angles for Real Driving Conditions

PubMed Central

Li, Zuojin; Li, Shengbo Eben; Li, Renjie; Cheng, Bo; Shi, Jinliang

2017-01-01

This paper presents a drowsiness on-line detection system for monitoring driver fatigue level under real driving conditions, based on the data of steering wheel angles (SWA) collected from sensors mounted on the steering lever. The proposed system firstly extracts approximate entropy (ApEn) features from fixed sliding windows on real-time steering wheel angles time series. After that, this system linearizes the ApEn features series through an adaptive piecewise linear fitting using a given deviation. Then, the detection system calculates the warping distance between the linear features series of the sample data. Finally, this system uses the warping distance to determine the drowsiness state of the driver according to a designed binary decision classifier. The experimental data were collected from 14.68 h driving under real road conditions, including two fatigue levels: “wake” and “drowsy”. The results show that the proposed system is capable of working online with an average 78.01% accuracy, 29.35% false detections of the “awake” state, and 15.15% false detections of the “drowsy” state. The results also confirm that the proposed method based on SWA signal is valuable for applications in preventing traffic accidents caused by driver fatigue. PMID:28257094

A Vehicle Active Safety Model: Vehicle Speed Control Based on Driver Vigilance Detection Using Wearable EEG and Sparse Representation

PubMed Central

Zhang, Zutao; Luo, Dianyuan; Rasim, Yagubov; Li, Yanjun; Meng, Guanjun; Xu, Jian; Wang, Chunbai

2016-01-01

In this paper, we present a vehicle active safety model for vehicle speed control based on driver vigilance detection using low-cost, comfortable, wearable electroencephalographic (EEG) sensors and sparse representation. The proposed system consists of three main steps, namely wireless wearable EEG collection, driver vigilance detection, and vehicle speed control strategy. First of all, a homemade low-cost comfortable wearable brain-computer interface (BCI) system with eight channels is designed for collecting the driver’s EEG signal. Second, wavelet de-noising and down-sample algorithms are utilized to enhance the quality of EEG data, and Fast Fourier Transformation (FFT) is adopted to extract the EEG power spectrum density (PSD). In this step, sparse representation classification combined with k-singular value decomposition (KSVD) is firstly introduced in PSD to estimate the driver’s vigilance level . Finally, a novel safety strategy of vehicle speed control, which controls the electronic throttle opening and automatic braking after driver fatigue detection using the above method, is presented to avoid serious collisions and traffic accidents. The simulation and practical testing results demonstrate the feasibility of the vehicle active safety model. PMID:26907278

An exploration of the potential impact of the designated driver campaign on bartenders' willingness to over-serve.

PubMed

Reiling, Denise M; Nusbaumer, Michael R

2007-12-01

Much has been written about the impact of the presence of a designated driver on patrons' consumption, but heretofore, its impact on the behaviour of the server has been virtually ignored. The goal of this paper, then, was to explore the potential impact of the presence of a designated driver on alcoholic beverage servers' self-reported willingness to knowingly serve an already intoxicated customer. chi(2) analysis of survey data collected from 938 licensed servers, in the state of Indiana, USA, was performed. Approximately 43% of the bartenders surveyed reported that they either would be or might be willing to over-serve an already intoxicated customer. Of those who answered the follow-up question as to under what conditions they would be willing to over-serve, almost 80% reported that they would do so if the patron were accompanied by a designated driver. The statistical significance of the relationship between these two variables (.000) raises the question of whether the Designated Driver Campaign has the latent function of enabling some servers to neutralize their responsibility for over-serving by disregarding other types of intoxication-related harm.

Keep the driver in control: Automating automobiles of the future.

PubMed

Banks, Victoria A; Stanton, Neville A

2016-03-01

Automated automobiles will be on our roads within the next decade but the role of the driver has not yet been formerly recognised or designed. Rather, the driver is often left in a passive monitoring role until they are required to reclaim control from the vehicle. This research aimed to test the idea of driver-initiated automation, in which the automation offers decision support that can be either accepted or ignored. The test case examined a combination of lateral and longitudinal control in addition to an auto-overtake system. Despite putting the driver in control of the automated systems by enabling them to accept or ignore behavioural suggestions (e.g. overtake), there were still issues associated with increased workload and decreased trust. These issues are likely to have arisen due to the way in which the automated system has been designed. Recommendations for improvements in systems design have been made which are likely to improve trust and make the role of the driver more transparent concerning their authority over the automated system. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

A very demanding spectrometer optical design for ExoMars Mission

NASA Astrophysics Data System (ADS)

Belenguer, T.; Fernandez-Rodriguez, M.; Colombo, M.; Diaz-Catalá, E.; Sanchez-Páramo, J.

2017-11-01

The objective of this report is to present the study performed for a specially demanding solution of a spectrometer [1] design based on a transmissive holographic grating especially designed to actuate as the dispersion element. The main driver of the design has been to obtain a device with a clear reduction in mass, power and mechanical envelope with respect to the previous configuration based on a prism and/or Echelle grating. This simplification is produced mainly at expense of the waveband range. This study has been carried out by Laboratorio de Instrumentación Espacial (LINES) optical designers from Instituto Nacional de Técnica Aeroespacial (INTA).

Perception and Biodynamics in Unalerted Precrash Response

PubMed Central

McGehee, Daniel V.; Carsten, Oliver M.J.

2010-01-01

This research seeks to better understand unalerted driver response just prior to a serious vehicle crash. Few studies have been able to view a crash from the inside—with a camera focused on the driver and occupants. Four studies are examined: 1) a high-fidelity simulator study with an unalerted intersection incursion crash among 107 drivers; 2) four crashes from the Virginia Tech Transportation Institute (VTTI) 100 car study; 3) 58 crashes from vehicles equipped with an event triggered video recorder; and 4) a custom-designed high-fidelity simulator experiment that examined unalerted driver response to a head-on crash with a heavy truck. Analyses concentrate on decomposing driver perception, action, facial and postural changes with a focus on describing the neurophysiologic mechanisms designed to respond to danger. Results indicate that drivers involved in severe crashes generally have preview that an impact is about to occur. They respond first with vehicle control inputs (accelerator pedal release) along with facial state changes and withdrawal of the head back towards the head restraint. These responses frequently occur almost simultaneously, providing safety system designers with a number of reliable driver performance measures to monitor. Understanding such mechanisms may assist future advanced driver assistance systems (ADAS), advanced restraints, model development of advanced anthropomorphic test dummies (ATDs), injury prediction and the integration of active and passive safety systems. PMID:21050614

Transition in Gas Turbine Engine Control System Architecture: Modular, Distributed, Embedded

DTIC Science & Technology

2009-08-01

Design + Development + Certification + Procurement + Life Cycle Cost = Net Savings for our Customers Approved for Public Release 16 Economic ...Supporting Small Quantity Electronics Need Broadly Applicable High Temperature Electronics Supply Base Approved for Public Release 17 Economic ...rc ec ures Approved for Public Release 18 Economic Drivers for New FADEC Designs FADEC Implementation Time Pacing Engine Development Issues • FADEC

Optimization of eyesafe avalanche photodiode lidar for automobile safety and autonomous navigation systems

NASA Astrophysics Data System (ADS)

Williams, George M.

2017-03-01

Newly emerging accident-reducing, driver-assistance, and autonomous-navigation technology for automobiles is based on real-time three-dimensional mapping and object detection, tracking, and classification using lidar sensors. Yet, the lack of lidar sensors suitable for meeting application requirements appreciably limits practical widespread use of lidar in trucking, public livery, consumer cars, and fleet automobiles. To address this need, a system-engineering perspective to eyesafe lidar-system design for high-level advanced driver-assistance sensor systems and a design trade study including 1.5-μm spot-scanned, line-scanned, and flash-lidar systems are presented. A cost-effective lidar instrument design is then proposed based on high-repetition-rate diode-pumped solid-state lasers and high-gain, low-excess-noise InGaAs avalanche photodiode receivers and focal plane arrays. Using probabilistic receiver-operating-characteristic analysis, derived from measured component performance, a compact lidar system is proposed that is capable of 220 m ranging with 5-cm accuracy, which can be readily scaled to a 360-deg field of regard.

Experimental testing of designated driver cues

DOT National Transportation Integrated Search

2000-07-27

In theory, the designated-driver concept holds great promise for reducing the incidences of drunk driving. It is simple, inexpensive, almost universally recognized, and generally positively regarded by the U.S. population as a means for avoiding drun...

Roundabout design and elderly drivers.

DOT National Transportation Integrated Search

2011-10-01

Many drivers are apprehensive to accept a roundabout as a viable form of intersection, but their : safety and mobility benefits are increasing their popularity among designers. This thesis is an indepth study of a specific approach at a roundabout in...

Driver expectancy in highway design and traffic operations

DOT National Transportation Integrated Search

1986-05-01

Expectancy relates to a driver's readiness to respond to situations, events, and information in predictable and successful ways. It influences the speed and accuracy of information handling, and affects all aspects of highway design and operations, a...

Modelling how drivers respond to a bicyclist crossing their path at an intersection: How do test track and driving simulator compare?

PubMed

Boda, Christian-Nils; Dozza, Marco; Bohman, Katarina; Thalya, Prateek; Larsson, Annika; Lubbe, Nils

2018-02-01

Bicyclist fatalities are a great concern in the European Union. Most of them are due to crashes between motorized vehicles and bicyclists at unsignalised intersections. Different countermeasures are currently being developed and implemented in order to save lives. One type of countermeasure, active safety systems, requires a deep understanding of driver behaviour to be effective without being annoying. The current study provides new knowledge about driver behaviour which can inform assessment programmes for active safety systems such as Euro NCAP. This study investigated how drivers responded to bicyclists crossing their path at an intersection. The influences of car speed and cyclist speed on the driver response process were assessed for three different crossing configurations. The same experimental protocol was tested in a fixed-base driving simulator and on a test track. A virtual model of the test track was used in the driving simulator to keep the protocol as consistent as possible across testing environments. Results show that neither car speed nor bicycle speed directly influenced the response process. The crossing configuration did not directly influence the braking response process either, but it did influence the strategy chosen by the drivers to approach the intersection. The point in time when the bicycle became visible (which depended on the car speed, the bicycle speed, and the crossing configuration) and the crossing configuration alone had the largest effects on the driver response process. Dissimilarities between test-track and driving-simulator studies were found; however, there were also interesting similarities, especially in relation to the driver braking behaviour. Drivers followed the same strategy to initiate braking, independent of the test environment. On the other hand, the test environment affected participants' strategies for releasing the gas pedal and regulating deceleration. Finally, a mathematical model, based on both experiments, is proposed to characterize driver braking behaviour in response to bicyclists crossing at intersections. This model has direct implications on what variables an in-vehicle safety system should consider and how tests in evaluation programs should be designed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prevalence of alcohol-impaired drivers based on random breath tests in a roadside survey in Catalonia (Spain).

PubMed

Alcañiz, Manuela; Guillén, Montserrat; Santolino, Miguel; Sánchez-Moscona, Daniel; Llatje, Oscar; Ramon, Lluís

2014-04-01

Sobriety checkpoints are not usually randomly located by traffic authorities. As such, information provided by non-random alcohol tests cannot be used to infer the characteristics of the general driving population. In this paper a case study is presented in which the prevalence of alcohol-impaired driving is estimated for the general population of drivers. A stratified probabilistic sample was designed to represent vehicles circulating in non-urban areas of Catalonia (Spain), a region characterized by its complex transportation network and dense traffic around the metropolis of Barcelona. Random breath alcohol concentration tests were performed during spring 2012 on 7596 drivers. The estimated prevalence of alcohol-impaired drivers was 1.29%, which is roughly a third of the rate obtained in non-random tests. Higher rates were found on weekends (1.90% on Saturdays and 4.29% on Sundays) and especially at night. The rate is higher for men (1.45%) than for women (0.64%) and it shows an increasing pattern with age. In vehicles with two occupants, the proportion of alcohol-impaired drivers is estimated at 2.62%, but when the driver was alone the rate drops to 0.84%, which might reflect the socialization of drinking habits. The results are compared with outcomes in previous surveys, showing a decreasing trend in the prevalence of alcohol-impaired drivers over time. Copyright © 2014 Elsevier Ltd. All rights reserved.

Driving Performance among Bioptic Telescope Users with Low Vision Two Years after Obtaining Their Driver's License: A Quasi-Experimental Study

ERIC Educational Resources Information Center

Vincent, Claude; Lachance, Jean-Paul; Deaudelin, Isabelle

2012-01-01

This study sought to compare road safety of new drivers with low vision who have followed a specific pilot bioptic training program with other groups of drivers all matched for age and driving experience. A quasi-experimental design was used two years after drivers obtained their license. Drivers were classified in the experimental group (n = 10,…

Fighting against a shortage of truck drivers in logistics: Measures that employers can take to promote drivers' work ability and health.

PubMed

Staats, Ulrike; Lohaus, Daniela; Christmann, Alina; Woitschek, Michèle

2017-01-01

For several years, the transportation industry has been concerned about a severe shortage of professional truck drivers. Studies investigating the reasons found that poor working conditions and stresses and strains resulting from physiological and psychological job demands have had a negative impact on drivers' health and ability to work. Nevertheless, until now, most employers have refrained from offering measures to support the work ability and well-being of drivers, mainly due to financial pressures in the industry. The present study was aimed at designing adequate and affordable measures to support drivers' health. With reference to the Work Ability Index and the house of work ability (Ilmarinen & Tuomi, 2004), 56 truck drivers participated in guided interviews about their working conditions and health-related problems as well as their attitudes, experiences, and desires with respect to being offered supportive measures by their employers. The measures derived are specific and realizable and expected to be widely accepted by professional drivers. They are designed to elicit a positive attitude in the drivers toward exercising and to help them overcome related psychological barriers. The implementation of the recommended measures can be expected to support drivers' work ability and help reduce the frictional costs of their employers.

Wildlife Warning Signs: Public Assessment of Components, Placement and Designs to Optimise Driver Response

PubMed Central

Bond, Amy R. F.; Jones, Darryl N.

2013-01-01

Simple Summary Wildlife warning signs are aimed at reducing wildlife–vehicle collisions but there is little evidence that they are effective. Improving these sign designs to increase driver response may reduce wildlife–vehicle collisions. We examined drivers’ responses to different wildlife warning sign designs through a public survey. The presences of some sign components and sign position were assessed. Drivers’ responses to eight graphically displayed signs and animal- and vehicle-activated signs were ranked and participants indicated the sign to which they were most likely to respond. Three signs ranked highly. Animal- and vehicle-activated signs were also ranked highly by participants. More research into optimising wildlife warning sign designs is needed. Abstract Wildlife warning signs are the most commonly used and widespread form of road impact mitigation, aimed at reducing the incidence of wildlife–vehicle collisions. Evidence of the effectiveness of currently used signs is rare and often indicates minimal change in driver behaviour. Improving the design of these signs to increase the likelihood of appropriate driver response has the potential to reduce the incidence of wildlife–vehicle collisions. This study aimed to examine and assess the opinions of drivers on wildlife warning sign designs through a public opinion survey. Three currently used sign designs and five alternative sign designs were compared in the survey. A total of 134 drivers were surveyed. The presence of temporal specifications and an updated count of road-killed animals on wildlife warning signs were assessed, as well as the position of the sign. Drivers’ responses to the eight signs were scaled separately at three speed limits and participants indicated the sign to which they were most likely to respond. Three signs consistently ranked high. The messages conveyed by these signs and their prominent features were explored. Animal-activated and vehicle speed-activated signs were ranked very highly by participants. Extensive field trials of various sign designs are needed to further this research into optimizing wildlife warning sign designs. PMID:26479756

Behavioral modeling of VCSELs for high-speed optical interconnects

NASA Astrophysics Data System (ADS)

Szczerba, Krzysztof; Kocot, Chris

2018-02-01

Transition from on-off keying to 4-level pulse amplitude modulation (PAM) in VCSEL based optical interconnects allows for an increase of data rates, at the cost of 4.8 dB sensitivity penalty. The resulting strained link budget creates a need for accurate VCSEL models for driver integrated circuit (IC) design and system level simulations. Rate equation based equivalent circuit models are convenient for the IC design, but system level analysis requires computationally efficient closed form behavioral models based Volterra series and neural networks. In this paper we present and compare these models.

A call to improve sampling methodology and reporting in young novice driver research.

PubMed

Scott-Parker, B; Senserrick, T

2017-02-01

Young drivers continue to be over-represented in road crash fatalities despite a multitude of research, communication and intervention. Evidence-based improvement depends to a great extent upon research methodology quality and its reporting, with known limitations in the peer-review process. The aim of the current research was to review the scope of research methodologies applied in 'young driver' and 'teen driver' research and their reporting in four peer-review journals in the field between January 2006 and December 2013. In total, 806 articles were identified and assessed. Reporting omissions included participant gender (11% of papers), response rates (49%), retention rates (39%) and information regarding incentives (44%). Greater breadth and specific improvements in study designs and reporting are thereby identified as a means to further advance the field. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

A three-channel LED driver with single line transportation technique

NASA Astrophysics Data System (ADS)

Yu, Caideng; Du, Yiying; Jiang, Qiao; Zhou, Yun; Lv, Jian

2012-10-01

Designed a three-channel LED driver, realized the single-wire transmission of cascade signal between the drive IC of LED. Including the MCU digital interface, date register, clock synchronization, PWM grayscale adjustment circuit, as well as high voltage driver circuit for LED, etc… The driver control LED displaying 256 gray. Chip will generate synchronous sampling clock signals according to the received serial signals, when 24 bits dates have been received, the output pin begins to transport the dates followed-up which are automotive shaped to the input of the next chip. When the date receiving becomes low level that represent RESET, the red, green and blue channels will export different signals based on different input dates. Through the external MCU, it is realized the Separate luminance, and by connecting chips in series it achieved the control of outdoor big screen' colorful display. The automatic shaping forward technique makes the number of chips cascading immune to the limitations of signal transmission, but only limited by the refresh speed.

Comparing statistical and machine learning classifiers: alternatives for predictive modeling in human factors research.

PubMed

Carnahan, Brian; Meyer, Gérard; Kuntz, Lois-Ann

2003-01-01

Multivariate classification models play an increasingly important role in human factors research. In the past, these models have been based primarily on discriminant analysis and logistic regression. Models developed from machine learning research offer the human factors professional a viable alternative to these traditional statistical classification methods. To illustrate this point, two machine learning approaches--genetic programming and decision tree induction--were used to construct classification models designed to predict whether or not a student truck driver would pass his or her commercial driver license (CDL) examination. The models were developed and validated using the curriculum scores and CDL exam performances of 37 student truck drivers who had completed a 320-hr driver training course. Results indicated that the machine learning classification models were superior to discriminant analysis and logistic regression in terms of predictive accuracy. Actual or potential applications of this research include the creation of models that more accurately predict human performance outcomes.

Human Factors in the Automated Highway System: Transferring Control to the Driver

DOT National Transportation Integrated Search

1995-10-01

Driver capabilities and limitations must be considered to ensure successful implementation of the Automated Highway System (AHS). Human factors investigations of driver performance characteristics provide the basis for determining system design confi...

The relation between driving experience and recognition of road signs relative to their locations.

PubMed

Borowsky, Avinoam; Shinar, David; Parmet, Yisrael

2008-04-01

Examine how driving experience and expectations affect the ability of experienced drivers to identify traffic signs--specifically, no right turn (NRT) and no left turn (NLT) at intersections. Failure to heed signs is a frequent cause of accidents, and the authors focused on the contributions of experience and expectancy to sign identification. Inexperienced and experienced drivers were connected to an eye tracker system and briefly exposed to various traffic scenes. Some of the pictures included an NRT sign at the expected location (on the right), and some included the same sign at an unexpected location (on the left). The same procedure was used with an NLT traffic sign. Experienced drivers identified traffic signs better than inexperienced drivers did when the signs were posted at the expected location but identified them worse than did inexperienced drivers when they were at unexpected locations. With experience, drivers' expectations regarding the expected location of traffic signs become so strong that violating these expectancies results in more identification errors among experienced drivers than among inexperienced drivers. To optimize experienced drivers' traffic sign identification, signs must be located in accordance with drivers' expectations--specifically, on the right side of the road. When signs are misplaced, crashes can be caused by inappropriate placement rather than inappropriate driving. Highway designers should ensure that their design conforms to standards that shape experienced drivers' expectations.

A Context-Aware EEG Headset System for Early Detection of Driver Drowsiness.

PubMed

Li, Gang; Chung, Wan-Young

2015-08-21

Driver drowsiness is a major cause of mortality in traffic accidents worldwide. Electroencephalographic (EEG) signal, which reflects the brain activities, is more directly related to drowsiness. Thus, many Brain-Machine-Interface (BMI) systems have been proposed to detect driver drowsiness. However, detecting driver drowsiness at its early stage poses a major practical hurdle when using existing BMI systems. This study proposes a context-aware BMI system aimed to detect driver drowsiness at its early stage by enriching the EEG data with the intensity of head-movements. The proposed system is carefully designed for low-power consumption with on-chip feature extraction and low energy Bluetooth connection. Also, the proposed system is implemented using JAVA programming language as a mobile application for on-line analysis. In total, 266 datasets obtained from six subjects who participated in a one-hour monotonous driving simulation experiment were used to evaluate this system. According to a video-based reference, the proposed system obtained an overall detection accuracy of 82.71% for classifying alert and slightly drowsy events by using EEG data alone and 96.24% by using the hybrid data of head-movement and EEG. These results indicate that the combination of EEG data and head-movement contextual information constitutes a robust solution for the early detection of driver drowsiness.

A Context-Aware EEG Headset System for Early Detection of Driver Drowsiness

PubMed Central

Li, Gang; Chung, Wan-Young

2015-01-01

Driver drowsiness is a major cause of mortality in traffic accidents worldwide. Electroencephalographic (EEG) signal, which reflects the brain activities, is more directly related to drowsiness. Thus, many Brain-Machine-Interface (BMI) systems have been proposed to detect driver drowsiness. However, detecting driver drowsiness at its early stage poses a major practical hurdle when using existing BMI systems. This study proposes a context-aware BMI system aimed to detect driver drowsiness at its early stage by enriching the EEG data with the intensity of head-movements. The proposed system is carefully designed for low-power consumption with on-chip feature extraction and low energy Bluetooth connection. Also, the proposed system is implemented using JAVA programming language as a mobile application for on-line analysis. In total, 266 datasets obtained from six subjects who participated in a one-hour monotonous driving simulation experiment were used to evaluate this system. According to a video-based reference, the proposed system obtained an overall detection accuracy of 82.71% for classifying alert and slightly drowsy events by using EEG data alone and 96.24% by using the hybrid data of head-movement and EEG. These results indicate that the combination of EEG data and head-movement contextual information constitutes a robust solution for the early detection of driver drowsiness. PMID:26308002

Weight Control Intervention for Truck Drivers: The SHIFT Randomized Controlled Trial, United States

PubMed Central

Wipfli, Brad; Thompson, Sharon V.; Elliot, Diane L.; Anger, W. Kent; Bodner, Todd; Hammer, Leslie B.; Perrin, Nancy A.

2016-01-01

Objectives. To evaluate the effectiveness of the Safety and Health Involvement For Truckers (SHIFT) intervention with a randomized controlled design. Methods. The multicomponent intervention was a weight-loss competition supported with body weight and behavioral self-monitoring, computer-based training, and motivational interviewing. We evaluated intervention effectiveness with a cluster-randomized design involving 22 terminals from 5 companies in the United States in 2012 to 2014. Companies were required to provide interstate transportation services and operate at least 2 larger terminals. We randomly assigned terminals to intervention or usual practice control conditions. We assessed participating drivers (n = 452) at baseline and 6 months. Results. In an intent-to-treat analysis, the postintervention difference between groups in mean body mass index change was 1.00 kilograms per meters squared (P < .001; intervention = −0.73; control = +0.27). Behavioral changes included statistically significant improvements in fruit and vegetable consumption and physical activity. Conclusions. Results establish the effectiveness of a multicomponent and remotely administered intervention for producing significant weight loss among commercial truck drivers. PMID:27463067

Weight Control Intervention for Truck Drivers: The SHIFT Randomized Controlled Trial, United States.

PubMed

Olson, Ryan; Wipfli, Brad; Thompson, Sharon V; Elliot, Diane L; Anger, W Kent; Bodner, Todd; Hammer, Leslie B; Perrin, Nancy A

2016-09-01

To evaluate the effectiveness of the Safety and Health Involvement For Truckers (SHIFT) intervention with a randomized controlled design. The multicomponent intervention was a weight-loss competition supported with body weight and behavioral self-monitoring, computer-based training, and motivational interviewing. We evaluated intervention effectiveness with a cluster-randomized design involving 22 terminals from 5 companies in the United States in 2012 to 2014. Companies were required to provide interstate transportation services and operate at least 2 larger terminals. We randomly assigned terminals to intervention or usual practice control conditions. We assessed participating drivers (n = 452) at baseline and 6 months. In an intent-to-treat analysis, the postintervention difference between groups in mean body mass index change was 1.00 kilograms per meters squared (P < .001; intervention = -0.73; control = +0.27). Behavioral changes included statistically significant improvements in fruit and vegetable consumption and physical activity. Results establish the effectiveness of a multicomponent and remotely administered intervention for producing significant weight loss among commercial truck drivers.

Material selection indices for design of surgical instruments with long tubular shafts.

PubMed

Nelson, Carl A

2013-02-01

In any medical device design process, material selection plays an important role. For devices which sustain mechanical loading, strength and stiffness requirements can be significant drivers of the design. This paper examines the specific case of minimally invasive surgical instruments, including robotic instruments, having long, tubular shafts. Material properties-based selection indices are derived for achieving high performance of these devices in terms of strength and stiffness, and the use of these indices for informing the medical device design problem is illustrated.

Design reuse experience of space and hazardous operations robots

NASA Technical Reports Server (NTRS)

Oneil, P. Graham

1994-01-01

A comparison of design drivers for space and hazardous nuclear waste operating robots details similarities and differences in operations, performance and environmental parameters for these critical environments. The similarities are exploited to provide low risk system components based on reuse principles and design knowledge. Risk reduction techniques are used for bridging areas of significant differences. As an example, risk reduction of a new sensor design for nuclear environment operations is employed to provide upgradeable replacement units in a reusable architecture for significantly higher levels of radiation.

Available sight distance on existing highways: Meeting stopping sight distance requirements of an aging population.

PubMed

Gargoum, Suliman A; Tawfeek, Mostafa H; El-Basyouny, Karim; Koch, James C

2018-03-01

An important element of highway design is ensuring that the available sight distance (ASD) on a highway meets driver needs. For instance, if the ASD at any point on a highway is less than the distance required to come to a complete stop after seeing a hazard (i.e. Stopping Sight Distance (SSD)), the driver will not be able to stop in time to avoid a collision. SSD is function of a number of variables which vary depending on the driver, the vehicle driven and surface conditions; examples of such variables include a driver's perception reaction time or PRT (i.e. the time required by the driver to perceive and react to a hazard) and the deceleration rate of the vehicle. Most design guides recommend deterministic values for PRT and deceleration rates. Although these values may serve the needs of the average driver, they may not satisfy the needs of drivers with limited abilities. In other words, even if the ASD exceeds required SSD defined in the design guide, it might not always satisfy the needs of all drivers. While it is impossible to design roads that satisfy the needs of all drivers, the fact that most developed countries suffer from an aging population, means that the number of old drivers on our roads is expected to increase. Since a large proportion of old drivers often have limited abilities, it is expected that the general population of drivers with limited abilities on our roads will increase with time. Accordingly, more efforts are required to ensure that existing road infrastructure is prepared to handle such a change. This paper aims to explore the extent to which ASD on highways satisfies the needs of drivers with limited abilities. The paper first develops MATLAB and Python codes to automatically estimate the ASD on highway point cloud data collected using Light Detection and Ranging (LiDAR) remote sensing technology. The developed algorithms are then used to estimate ASD on seven different crash prone segments in the Province of Alberta, Canada and the ASD is compared to the required SSD on each highway. Three different levels of SSD are defined (SSD for drivers with limited ability, AASHTOs SSD requirements and SSD for drivers with high skill). The results show that, when compared to SSD requirements which integrate limitations in cognitive abilities, a substantial portion of the analyzed segments do not meet the requirements (up to 20%). Similarly, when compared to AASHTO's SSD requirements, up to 6% of the analyzed segments do not meet the requirements. In an attempt to explore the effects of such design limitations on safety, the paper also explores crash rates in noncompliant regions (i.e. regions that do not provide sufficient SSD) and compares them to crash rates in compliant regions. On average, it was found that noncompliant regions experience crash rates that are 2.15 and 1.25 times higher than compliant regions for AASHTO's SSD requirements and those integrating driver limitations, respectively. Furthermore, the study found that a significantly higher proportion of drivers involved in collisions in the noncompliant regions were old drivers. Copyright © 2018 Elsevier Ltd. All rights reserved.

Building Work-Based Learning into the School Curriculum

ERIC Educational Resources Information Center

Asher, Jenny

2005-01-01

Purpose - The purpose of this article is to examine the increasing number of opportunities for pre-16 young people at schools in England to become involved in work related and work based programmes and to look at the key drivers of change and their impact. Design/methodology/approach - The approach is descriptive, covering current trends and also…

Driving difficulties in Parkinson's disease

PubMed Central

Rizzo, Matthew; Uc, Ergun Y; Dawson, Jeffrey; Anderson, Steven; Rodnitzky, Robert

2011-01-01

Safe driving requires the coordination of attention, perception, memory, motor and executive functions (including decision-making) and self-awareness. PD and other disorders may impair these abilities. Because age or medical diagnosis alone is often an unreliable criterion for licensure, decisions on fitness to drive should be based on empirical observations of performance. Linkages between cognitive abilities measured by neuropsychological tasks, and driving behavior assessed using driving simulators, and natural and naturalistic observations in instrumented vehicles, can help standardize the assessment of fitness-to-drive. By understanding the patterns of driver safety errors that cause crashes, it may be possible to design interventions to reduce these errors and injuries and increase mobility. This includes driver performance monitoring devices, collision alerting and warning systems, road design, and graded licensure strategies. PMID:20187237

Comparison of a Virtual Older Driver Assessment with an On-Road Driving Test.

PubMed

Eramudugolla, Ranmalee; Price, Jasmine; Chopra, Sidhant; Li, Xiaolan; Anstey, Kaarin J

2016-12-01

To design a low-cost simulator-based driving assessment for older adults and to compare its validity with that of an on-road driving assessment and other measures of older driver risk. Cross-sectional observational study. Canberra, Australia. Older adult drivers (N = 47; aged 65-88, mean age 75.2). Error rate on a simulated drive with environment and scoring procedure matched to those of an on-road test. Other measures included participant age, simulator sickness severity, neuropsychological measures, and driver screening measures. Outcome variables included occupational therapist (OT)-rated on-road errors, on-road safety rating, and safety category. Participants' error rate on the simulated drive was significantly correlated with their OT-rated driving safety (correlation coefficient (r) = -0.398, P = .006), even after adjustment for age and simulator sickness (P = .009). The simulator error rate was a significant predictor of categorization as unsafe on the road (P = .02, sensitivity 69.2%, specificity 100%), with 13 (27%) drivers assessed as unsafe. Simulator error was also associated with other older driver safety screening measures such as useful field of view (r = 0.341, P = .02), DriveSafe (r = -0.455, P < .01), and visual motion sensitivity (r = 0.368, P = .01) but was not associated with memory (delayed word recall) or global cognition (Mini-Mental State Examination). Drivers made twice as many errors on the simulated assessment as during the on-road assessment (P < .001), with significant differences in the rate and type of errors between the two mediums. A low-cost simulator-based assessment is valid as a screening instrument for identifying at-risk older drivers but not as an alternative to on-road evaluation when accurate data on competence or pattern of impairment is required for licensing decisions and training programs. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

Supplemental Driver Safety Program Development. Volume I--Development Research and Evaluation. Final Report.

ERIC Educational Resources Information Center

McPherson, Kenard; And Others

Instructional modules for driver education programs were prepared to improve safe driving knowledge, attitudes, and performances of 16- to 18-year-old drivers. These modules were designed to provide supplementary instruction in five content areas critical to the safe and efficient operation of motor vehicles by young drivers--speed management,…

Driver license testing of young novice drivers : traffic tech.

DOT National Transportation Integrated Search

2010-11-01

Driver license tests are designed to ensure that people using : public roadways have a minimum level of driving skill and : an awareness of safe driving practices and road laws. License : applicants proceed through the administrative processes of : t...

Vehicle emission implications of drivers' smart advisory system for traffic operations in work zones.

PubMed

Li, Qing; Qiao, Fengxiang; Yu, Lei

2016-05-01

Wireless communication systems have been broadly applied in various complicated traffic operations to improve mobility and safety on roads, which may raise a concern about the implication of the new technology on vehicle emissions. This paper explores how the wireless communication systems improve drivers' driving behaviors and its contributions to the emission reduction, in terms of Operating Mode (OpMode) IDs distribution used in emission estimation. A simulated work zone with completed traffic operation was selected as a test bed. Sixty subjects were recruited for the tests, whose demographic distribution was based on the Census data in Houston, Texas. A scene of a pedestrian's crossing in the work zone was designed for the driving test. Meanwhile, a wireless communication system called Drivers Smart Advisory System (DSAS) was proposed and introduced in the driving simulation, which provided drivers with warning messages in the work zone. Two scenarios were designed for a leading vehicle as well as for a following vehicle driving through the work zone, which included a base test without any wireless communication systems, and a driving test with the trigger of the DSAS. Subjects' driving behaviors in the simulation were recorded to evaluate safety and estimate the vehicle emission using the Environmental Protection Agency (EPA) released emission model MOVES. The correlation between drivers' driving behavior and the distribution of the OpMode ID during each scenario was investigated. Results show that the DSAS was able to induce drivers to accelerate smoothly, keep longer headway distance and stop earlier for a hazardous situation in the work zone, which driving behaviors result in statistically significant reduction in vehicle emissions for almost all studied air pollutants (p-values range from 4.10E-51 to 2.18E-03). The emission reduction was achieved by the switching the distribution of the OpMode IDs from higher emission zones to lower emission zones. Transportation section is a significant source of greenhouse gas emissions. Many studies demonstrate that the wireless communication system dedicated for safety and mobility issues may contribute to the induction in vehicle emissions through changing driving behaviors. An insight into the correlation between the driving behaviors and the distribution of Operating Mode (OpMode) IDs is essential to enhance the emission reduction. The result of this study shows that with a Drivers Smart Advisory System (DSAS) drivers accelerated smoothly and stopped earlier for a hazardous situation, which induce the switch of the OpMode IDs from high emission zones to lower emission zones.

New amplifying laser concept for inertial fusion driver

NASA Astrophysics Data System (ADS)

Mourou, G. A.; Labaune, C.; Hulin, D.; Galvanauskas, A.

2008-05-01

This paper presents a new amplifying laser concept designed to produce high energy in either short or long pulses using coherent or incoherent addition of few millions fibers. These are called respectively CAN for Coherent Amplification Network and FAN for Fiber Amplification Network. The fibers would be large core or Large Mode Area (LMA) which have demonstrated up to 10, mJ output energy per fiber1. Such a system could meet the driver criteria of Inertial Fusion Energy (IFE) power plants based on Inertial Confinement Fusion (ICF), in particular high efficiency and high repetition rate.

Multi-Attribute Tradespace Exploration in Space System Design

NASA Astrophysics Data System (ADS)

Ross, A. M.; Hastings, D. E.

2002-01-01

The complexity inherent in space systems necessarily requires intense expenditures of resources both human and monetary. The high level of ambiguity present in the early design phases of these systems causes long, highly iterative, and costly design cycles. This paper looks at incorporating decision theory methods into the early design processes to streamline communication of wants and needs among stakeholders and between levels of design. Communication channeled through formal utility interviews and analysis enables engineers to better understand the key drivers for the system and allows a more thorough exploration of the design tradespace. Multi-Attribute Tradespace Exploration (MATE), an evolving process incorporating decision theory into model and simulation- based design, has been applied to several space system case studies at MIT. Preliminary results indicate that this process can improve the quality of communication to more quickly resolve project ambiguity, and enable the engineer to discover better value designs for multiple stakeholders. MATE is also being integrated into a concurrent design environment to facilitate the transfer knowledge of important drivers into higher fidelity design phases. Formal utility theory provides a mechanism to bridge the language barrier between experts of different backgrounds and differing needs (e.g. scientists, engineers, managers, etc). MATE with concurrent design couples decision makers more closely to the design, and most importantly, maintains their presence between formal reviews.

Multi-hazard Assessment and Scenario Toolbox (MhAST): A Framework for Analyzing Compounding Effects of Multiple Hazards

NASA Astrophysics Data System (ADS)

Sadegh, M.; Moftakhari, H.; AghaKouchak, A.

2017-12-01

Many natural hazards are driven by multiple forcing variables, and concurrence/consecutive extreme events significantly increases risk of infrastructure/system failure. It is a common practice to use univariate analysis based upon a perceived ruling driver to estimate design quantiles and/or return periods of extreme events. A multivariate analysis, however, permits modeling simultaneous occurrence of multiple forcing variables. In this presentation, we introduce the Multi-hazard Assessment and Scenario Toolbox (MhAST) that comprehensively analyzes marginal and joint probability distributions of natural hazards. MhAST also offers a wide range of scenarios of return period and design levels and their likelihoods. Contribution of this study is four-fold: 1. comprehensive analysis of marginal and joint probability of multiple drivers through 17 continuous distributions and 26 copulas, 2. multiple scenario analysis of concurrent extremes based upon the most likely joint occurrence, one ruling variable, and weighted random sampling of joint occurrences with similar exceedance probabilities, 3. weighted average scenario analysis based on a expected event, and 4. uncertainty analysis of the most likely joint occurrence scenario using a Bayesian framework.

Improved self-confidence was a mechanism of action in two geriatric trials evaluating physical interventions.

PubMed

Peduzzi, Peter; Guo, Zhenchao; Marottoli, Richard A; Gill, Thomas M; Araujo, Katy; Allore, Heather G

2007-01-01

To evaluate the mechanisms of action in two successful geriatric clinical trials that tested multicomponent physical conditioning programs and to determine whether the pathways for overall benefit were through improvement in physical ability and/or self-confidence. PREHAB and DRIVER were conducted by the Yale Pepper Center. PREHAB participants received an individualized program that focused on the impairments present (standardly tailored design); DRIVER participants received the entire intervention (global design). PREHAB enrolled 188 community-living persons, aged 75 years or older, who were physically frail but ambulatory; DRIVER enrolled 178 drivers aged 70 years or older with physical impairments associated with poor driving performance. The primary outcome for PREHAB was a disability score and for DRIVER it was a driving score; potential mediators were measures of physical ability and self-confidence. In PREHAB, pathways for the intervention were established through improvement in physical ability and self-confidence. In DRIVER, there was some evidence for a pathway through improved driving self-confidence but not through physical ability; however, the intervention effect was largely unexplained. Multicomponent physical interventions may operate through psychological mechanisms, and these mechanisms should be anticipated in trial designs so that the component effects can be suitably evaluated.

Injury mitigation estimates for an intersection driver assistance system in straight crossing path crashes in the United States.

PubMed

Scanlon, John M; Sherony, Rini; Gabler, Hampton C

2017-05-29

Accounting for one fifth of all crashes and one sixth of all fatal crashes in the United States, intersection crashes are among the most frequent and fatal crash modes. Intersection advanced driver assistance systems (I-ADAS) are emerging vehicle-based active safety systems that aim to help drivers safely navigate intersections. The objective of this study was to estimate the number of crashes and number of vehicles with a seriously injured driver (Maximum Abbreviated Injury Scale [MAIS] 3+) that could be prevented or reduced if, for every straight crossing path (SCP) intersection crash, one of the vehicles had been equipped with an I-ADAS. This study retrospectively simulated 448 U.S. SCP crashes as if one of the vehicles had been equipped with I-ADAS. Crashes were reconstructed to determine the path and speeds traveled by the vehicles. Cases were then simulated with I-ADAS. A total of 30 variations of I-ADAS were considered in this study. These variations consisted of 5 separate activation timing thresholds, 3 separate computational latency times, and 2 different I-ADAS response modalities (i.e., a warning or autonomous braking). The likelihood of a serious driver injury was computed for every vehicle in every crash using impact delta-V. The results were then compiled across all crashes in order to estimate system effectiveness. The model predicted that an I-ADAS that delivers an alert to the driver has the potential to prevent 0-23% of SCP crashes and 0-25% of vehicles with a seriously injured driver. Conversely, an I-ADAS that autonomously brakes was found to have the potential to prevent 25-59% of crashes and 38-79% of vehicles with a seriously injured driver. I-ADAS effectiveness is a strong function of design. Increasing computational latency time from 0 to 0.5 s was found to reduce crash and injury prevention estimates by approximately one third. For an I-ADAS that delivers an alert, crash/injury prevention effectiveness was found to be very sensitive to changes in activation timing (warning delivered 1.0 to 3.0 s prior to impact). If autonomous braking was used, system effectiveness was found to largely plateau for activation timings greater than 1.5 s prior to impact. In general, the results of this study suggest that I-ADAS will be 2-3 times more effective if an autonomous braking system is utilized over a warning-based system. This study highlights the potential effectiveness of I-ADAS in the U.S. vehicle fleet, while also indicating the sensitivity of system effectiveness to design specifications. The results of this study should be considered by designers of I-ADAS and evaluators of this technology considering a future I-ADAS safety test.

Last Call: decreasing drunk driving among 21-34-year-old bar patrons.

PubMed

Rivara, Frederick P; Boisvert, Deanne; Relyea-Chew, Annemarie; Gomez, Tony

2012-01-01

Any effort to decrease the toll of drunk driving must include efforts directed at people who drink in bars, particularly young adults who use motor vehicles after drinking. We designed a multifaceted social marketing campaign, Last Call, to increase the use of designated drivers and safe rides homes among 21-34-year olds. There were three components to the intervention: (1) use of taxi stands to promote taxi use; (2) point-of-sale information to patrons at partner bars and (3) a mass media campaign to support the designated driver/safe ride home message. Among the heaviest drinkers, the programme significantly increased the use of designated drivers and increased the use of taxis by 63%.

Assessment of truck driver distraction problem and research needs

DOT National Transportation Integrated Search

2005-05-01

The issue of driver distraction associated with the use of in-vehicle devices in heavy vehicles was explored through interviews with truck drivers and safety regulators. In order to characterize some of the interface designs and better understand the...

How shall we design the future vehicle for Chinese market.

PubMed

Chen, Fang; Wang, Minjuan; Zhu, Xi Chan; Li, Jiaqi

2012-01-01

Surface transportation system is developing very fast in China and the number of vehicles is increasing quickly as well. This development creates a lot of problems on traffic safety and the number of accident is also increasing. In this paper, we made deep analysis of different possible causes of safety problems through three aspects: the traffic environment and infrastructure, in-vehicle information system design and the characteristics of drivers. There are many factors in each aspects may contribute to the transportation safety problems. Problems with infrastructure design and traffic design contribute over 50% of the traffic accident. Another important factor is that people has very little traffic safety concept and very weak on understanding the important of right behavior on the road. This paper has pointed the urgent needs to study the human factors in road and transportation system and vehicle HMI design, as there are very few such studies available in literature based on Chinese situation. The paper also proposed the needs to develop proactive educational system that can promote driver's understanding of traffic safety and to take the right action during drive.

Let Them Through.... It Could Be You

DOT National Transportation Integrated Search

1996-06-17

A major challenge for designers of ATIS is to design displays that do not overload the driver. This is a particular concern for older drivers who may have decrements in the abilities required for safe driving. To compare information provided by an AT...

Review and assessment of designated driver programs as an alcohol countermeasure approach

DOT National Transportation Integrated Search

1987-02-01

Many drinking establishments have instituted designated driver programs (DDPs) which encourage one person in a group of patrons to remain sober and drive the others home. The primary objectives of this exploratory study were to: 1) identify DDPs thro...

Design, development, and evaluation of truck and bus driver wellness programs

DOT National Transportation Integrated Search

2000-06-01

In May 1997, the Federal Motor Carrier Safety Administration (FMCSA) began a research project to design, develop, and evaluate a model truck and bus driver wellness program. This wellness program was developed to provide a resource for addressing tru...

49 CFR 571.126 - Standard No. 126; Electronic stability control systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... driver on the previous ignition cycle that is designed for low-speed, off-road driving, or (b) the... is designed for operation at higher speeds on snow-, sand-, or dirt-packed roads and that has the... dealer, fully fueled, with a 73 kg (160 lb) driver. Standard outriggers shall be designed with a maximum...

Virtual testing of speed reduction schemes on urban collector roads.

PubMed

Domenichini, Lorenzo; Branzi, Valentina; Meocci, Monica

2018-01-01

Urban collector roads are complex driving environments often encompassing both the mobility and the access road functions. In these conditions motorized traffic and vulnerable road users compete continually. Speed reduction measures may play a relevant role in these contexts, provided that such measures are also designed in compliance with the driver's capabilities and expectations. The paper describes a test procedure using driving simulation experiments, designed to evaluate the reconfiguration project of Via Pistoiese, an urban road collector located in Florence (Italy). The road improvement design consisted of several engineering treatments aimed to reduce and homogenize the driving speed, as well as to manage the co-existence of the different road users and mainly to protect pedestrians. The main focus of the research was to understand if the drivers' behaviour was according to the design hypothesis before the safety treatments are implemented in the real world. Due to the multiple engineering treatments included in the reconfiguration project, the evaluation of the overall safety effectiveness of the project rather than the single treatment safety impact was the main concern of the research study. In addition, the study aimed to assess the usefulness of the considered testing method to understand how to integrate road design with drivers' performances, especially in heterogeneous traffic environments where drivers' behaviour plays a decisive role in the success of the proposed design solutions. Fifty-eight participants drove through two immersive virtual environments, reproducing the existing configuration and the project reconfiguration, while data relating to different driving aspects were collected. Two analyses were performed. The first was focused on the analysis of the mean speed profiles and revealed that the considered engineering treatments are able to control the speeding behaviour without providing a too high discomfort to the drivers. The second analysis was finalized to evaluate the driver's behaviour approaching zebra crossing, evaluating the impact of countermeasures allowing the drivers to perceive in advance a critical situation (a pedestrian that suddenly crossed the street) and consequently to perform a smoother and safer manoeuvre. The experiments confirmed the validity of the considered engineering treatments, allowing expecting the improvement of the traffic safety in via Pistoiese, and support the usefulness of virtual reality experimentations to predict of the safety effectiveness of design solutions, taking into account the drivers' behaviour. Copyright © 2017 Elsevier Ltd. All rights reserved.

Parents' and peers' contribution to risky driving of male teen drivers.

PubMed

Taubman - Ben-Ari, Orit; Kaplan, Sigal; Lotan, Tsippy; Prato, Carlo Giacomo

2015-05-01

The current study joins efforts devoted to understanding the associations of parents' personality, attitude, and behavior, and to evaluating the added contribution of peers to the driving behavior of young drivers during their solo driving. The study combines data gathered using in-vehicle data recorders from actual driving of parents and their male teen driver with data collected from self-report questionnaires completed by the young drivers. The sample consists of 121 families, who participated in the study for 12 months, beginning with the licensure of the teen driver. The current examination concentrates on the last 3 months of this first year of driving. The experimental design was based on a random control assignment into three treatment groups (with different forms of feedback) and a control group (with no feedback). Findings indicate that the parents' (especially the fathers') sensation seeking, anxiety, and aggression, as well as their risky driving events rate were positively associated with higher risky driving of the young driver. In addition, parents' involvement in the intervention, either by feedback or by training, led to lower risky driving events rate of young drivers compared to the control group. Finally, higher cohesion and adaptability mitigated parents' model for risky driving, and peers norms' of risky driving were associated with higher risk by the teen drivers. We conclude by claiming that there is an unequivocal need to look at a full and complex set of antecedents in parents' personality, attitudes, and behavior, together with the contribution of peers to the young drivers' reckless driving, and address the practical implications for road safety. Copyright © 2015 Elsevier Ltd. All rights reserved.

Designing Fatigue Warning Systems: The perspective of professional drivers.

PubMed

Meng, Fanxing; Li, Shuling; Cao, Lingzhi; Peng, Qijia; Li, Musen; Wang, Chunhui; Zhang, Wei

2016-03-01

Professional drivers have been characterized as experiencing heavy fatigue resulting from long driving time in their daily work. This study aimed to explore the potential demand of Fatigue Warning Systems (FWSs) among professional drivers as a means of reducing the danger of fatigue driving and to examine their opinions regarding the design of FWSs. Six focus groups with 35 participants and a questionnaire survey with 600 respondents were conducted among Chinese truck and taxi drivers to collect qualitative and quantitative data concerning the current situation of fatigue driving and opinions regarding the design of FWSs. The results revealed that both truck and taxi drivers had a positive attitude toward FWSs, and they hoped this system could not only monitor and warn them regarding their fatigue but also somewhat relieve their fatigue before they could stop and rest. As for warning signals, participants preferred auditory warnings, as opposed to visual, vibrotactile or electric stimuli. Interestingly, it was proposed that verbal warnings involving the information regarding consequences of fatigue driving or the wishes of drivers' family members would be more effective. Additionally, different warning patterns, including graded, single and continuous warnings, were discussed in the focus group. Finally, the participants proposed many other suggestions, as well as their concerns regarding FWSs, which will provide valuable information for companies who wish to develop FWSs for professional drivers. Copyright © 2015. Published by Elsevier Ltd.

Understanding driver performance variability and perception of risk : driver hazard perception research plan

DOT National Transportation Integrated Search

1998-01-01

The objectives of this research project were to develop a comprehensive and clearly defined research program to define, : measure, and quantify driver perception of hazards as it relates to highway design, operations, and safety, standards This was :...

Increasing the default interletter spacing of words can help drivers to read traffic signs at longer distances.

PubMed

Tejero, Pilar; Insa, Beatriz; Roca, Javier

2018-08-01

Would an increase in the default interletter spacing improve the legibility of words in traffic signs? Previous evidence on traffic sign design and recent studies on the cognitive processes involved in visual word recognition have provided conflicting results. The present work examined whether an increase in the default interletter spacing would improve the search of a word in direction traffic signs. To achieve this objective, twenty-two drivers participated in a driving simulation experiment. They followed a highway route and indicated whether a target place name was present among a set of distractors shown on direction traffic signs along the route. We compared the default interletter spacing of the Spanish "CC Rige" font (which is based on the internationally-used Transport font) and a 2.5-times expanded interletter spacing. The results revealed that the drivers were able to give a correct response at a distance to the traffic sign that was on average longer in the expanded than in the default spacing condition. This advantage in the legibility distance was observed in the absence of significant differences in reading accuracy, gaze behavior, or driving performance measures. Therefore, the evidence provided supports that drivers can benefit from a slight increase in interletter spacing relative to the standard spacing. Some of the design factors influencing this effect are discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Classification of driving workload affected by highway alignment conditions based on classification and regression tree algorithm.

PubMed

Hu, Jiangbi; Wang, Ronghua

2018-02-17

Guaranteeing a safe and comfortable driving workload can contribute to reducing traffic injuries. In order to provide safe and comfortable threshold values, this study attempted to classify driving workload from the aspects of human factors mainly affected by highway geometric conditions and to determine the thresholds of different workload classifications. This article stated a hypothesis that the values of driver workload change within a certain range. Driving workload scales were stated based on a comprehensive literature review. Through comparative analysis of different psychophysiological measures, heart rate variability (HRV) was chosen as the representative measure for quantifying driving workload by field experiments. Seventy-two participants (36 car drivers and 36 large truck drivers) and 6 highways with different geometric designs were selected to conduct field experiments. A wearable wireless dynamic multiparameter physiological detector (KF-2) was employed to detect physiological data that were simultaneously correlated to the speed changes recorded by a Global Positioning System (GPS) (testing time, driving speeds, running track, and distance). Through performing statistical analyses, including the distribution of HRV during the flat, straight segments and P-P plots of modified HRV, a driving workload calculation model was proposed. Integrating driving workload scales with values, the threshold of each scale of driving workload was determined by classification and regression tree (CART) algorithms. The driving workload calculation model was suitable for driving speeds in the range of 40 to 120 km/h. The experimental data of 72 participants revealed that driving workload had a significant effect on modified HRV, revealing a change in driving speed. When the driving speed was between 100 and 120 km/h, drivers showed an apparent increase in the corresponding modified HRV. The threshold value of the normal driving workload K was between -0.0011 and 0.056 for a car driver and between -0.00086 and 0.067 for a truck driver. Heart rate variability was a direct and effective index for measuring driving workload despite being affected by multiple highway alignment elements. The driving workload model and the thresholds of driving workload classifications can be used to evaluate the quality of highway geometric design. A higher quality of highway geometric design could keep driving workload within a safer and more comfortable range. This study provided insight into reducing traffic injuries from the perspective of disciplinary integration of highway engineering and human factor engineering.

Autonomous Driver Based on an Intelligent System of Decision-Making.

PubMed

Czubenko, Michał; Kowalczuk, Zdzisław; Ordys, Andrew

The paper presents and discusses a system ( xDriver ) which uses an Intelligent System of Decision-making (ISD) for the task of car driving. The principal subject is the implementation, simulation and testing of the ISD system described earlier in our publications (Kowalczuk and Czubenko in artificial intelligence and soft computing lecture notes in computer science, lecture notes in artificial intelligence, Springer, Berlin, 2010, 2010, In Int J Appl Math Comput Sci 21(4):621-635, 2011, In Pomiary Autom Robot 2(17):60-5, 2013) for the task of autonomous driving. The design of the whole ISD system is a result of a thorough modelling of human psychology based on an extensive literature study. Concepts somehow similar to the ISD system can be found in the literature (Muhlestein in Cognit Comput 5(1):99-105, 2012; Wiggins in Cognit Comput 4(3):306-319, 2012), but there are no reports of a system which would model the human psychology for the purpose of autonomously driving a car. The paper describes assumptions for simulation, the set of needs and reactions (characterizing the ISD system), the road model and the vehicle model, as well as presents some results of simulation. It proves that the xDriver system may behave on the road as a very inexperienced driver.

Organizational Design Drivers to Enable Emergent Creativity in Web-Based Communities

ERIC Educational Resources Information Center

De Toni, Alberto F.; Biotto, Gianluca; Battistella, Cinzia

2012-01-01

Purpose: In the stream of works studying complexity from an organizational viewpoint, literature is focused mainly on describing new organizational forms (holonic organization, circular organization, virtual corporation, ...) and on conceptual works identifying new managerial principles to manage emergence (job enrichment, de-regulation, ...). But…

Effects of electronic billboards on driver distraction.

PubMed

Dukic, Tania; Ahlstrom, Christer; Patten, Christopher; Kettwich, Carmen; Kircher, Katja

2013-01-01

There is an increase in electronic advertising billboards along major roads, which may cause driver distraction due to the highly conspicuous design of the electronic billboards. Yet limited research on the impact of electronic billboards on driving performance and driver behavior is available. The Swedish Transport Administration recently approved the installation of 12 electronic billboards for a trial period along a 3-lane motorway with heavy traffic running through central Stockholm, Sweden. The aim of this study was to evaluate the effect of these electronic billboards on visual behavior and driving performance. A total of 41 drivers were recruited to drive an instrumented vehicle passing 4 of the electronic billboards during day and night conditions. A driver was considered visually distracted when looking at a billboard continuously for more than 2 s or if the driver looked away from the road for a high percentage of time. Dependent variables were eye-tracking measures and driving performance measures. The visual behavior data showed that drivers had a significantly longer dwell time, a greater number of fixations, and longer maximum fixation duration when driving past an electronic billboard compared to other signs on the same road stretches. No differences were found for the factors day/night, and no effect was found for the driving behavior data. Electronic billboards have an effect on gaze behavior by attracting more and longer glances than regular traffic signs. Whether the electronic billboards attract too much attention and constitute a traffic safety hazard cannot be answered conclusively based on the present data.

X-Band, 17-Watt Solid-State Power Amplifier

NASA Technical Reports Server (NTRS)

Mittskus, Anthony; Stone, Ernest; Boger, William; Burgess, David; Honda, Richard; Nuckolls, Carl

2005-01-01

An advanced solid-state power amplifier that can generate an output power of as much as 17 W at a design operating frequency of 8.4 GHz has been designed and constructed as a smaller, lighter, less expensive alternative to traveling-wave-tube X-band amplifiers and to prior solid-state X-band power amplifiers of equivalent output power. This amplifier comprises a monolithic microwave integrated circuit (MMIC) amplifier module and a power-converter module integrated into a compact package (see Figure 1). The amplifier module contains an input variable-gain amplifier (VGA), an intermediate driver stage, a final power stage, and input and output power monitors (see Figure 2). The VGA and the driver amplifier are 0.5-m GaAs-based metal semiconductor field-effect transistors (MESFETs). The final power stage contains four parallel high-efficiency, GaAs-based pseudomorphic high-electron-mobility transistors (PHEMTs). The gain of the VGA is voltage-variable over a range of 10 to 24 dB. To provide for temperature compensation of the overall amplifier gain, the gain-control voltage is generated by an operational-amplifier circuit that includes a resistor/thermistor temperature-sensing network. The driver amplifier provides a gain of 14 dB to an output power of 27 dBm to drive the four parallel output PHEMTs, each of which is nominally capable of putting out as much as 5 W. The driver output is sent to the input terminals of the four parallel PHEMTs through microstrip power dividers; the outputs of these PHEMTs are combined by microstrip power combiners (which are similar to the microstrip power dividers) to obtain the final output power of 17 W.

Design and Implementation of Vehicle Navigation System in Urban Environments using Internet of Things (Iot)

NASA Astrophysics Data System (ADS)

Godavarthi, Bhavana; Nalajala, Paparao; Ganapuram, Vasavi

2017-08-01

Advanced vehicle monitoring and tracking system based on embedded Linux board and android application is designed and implemented for monitoring the school vehicle from any location A to location B at real time. The present system would make good use of new technology that based on embedded Linux namely Raspberry Pi and Smartphone android application. This system works on GPS/GPRS/GSM SIM900A. GPS finds the current location of the vehicle, GPRS sends the tracking information to the server and the GSM is used for sending alert message to vehicle’s owner mobile. This system is placed inside the vehicle whose position is to be determined on the web page and monitored at real time. There is a comparison between the current vehicle path already specified paths into the file system. Inside the raspberry pi’s file system taken from vehicle owners through android phone using android application. Means the selection of path from location A to B takes place from vehicle owner’s android application which gives more safety and secures traveling to the traveler. Hence the driver drives the vehicle only on the vehicle owner’s specified path. The driver drives the vehicle only on the vehicle owner’s specified path but if the driver drives in wrong path the message alert will be sent from this system to the vehicle owners mobile and also sent speakers alert to driver through audio jack. If the vehicles speed goes beyond the specified value of the speed, then warning message will be sent to owner mobile. This system also takes care of the traveler’s safety by using Gas leakage and Temperature sensors

Driver training interests of a Spanish sample of young drivers and its relationship with their self-assessment skills concerning risky driving behavior.

PubMed

Molina, J Gabriel; Sanmartín, Jaime; Keskinen, Esko

2013-03-01

Poor driving self-assessment skills (e.g., over-confidence) have been pointed out as an important explanatory factor behind young drivers' accident involvement. This paper explores (1) what young drivers miss in their training as drivers in order to analyze whether an assessment of one's own driving skills plays an important role in their desire to improve as drivers, and (2) how these training interests are related to an estimate of their self-assessment skills concerning risky driving behavior. For this purpose, a study was conducted using a survey with a blocked sampling design of novice drivers. The survey solicited respondents' self-report about (1) the contents of training courses that they feel would improve their driving, (2) their risky driving behavior, and (3) their likelihood of being involved in a risky driving situation. From the initial sample invited to participate, of nearly 1300 people, we finally obtained complete data from 321 young Spanish drivers. Two main results were apparent from our data analysis: (1) the novice drivers were mainly interested in improving their ability to recognize their strengths and weaknesses as drivers (i.e., self-assessment skills); (2) a significant relationship was found between novice drivers' interests and their current self-assessment skills concerning risky driving behavior. Specifically, there was greater general interest expressed in post-license training by the under-confident self-assessors than the over-confident ones. These results provide a relevant input which should be taken into account when designing driver training programs for novice drivers. Moreover, the relationship between their training interests and their risky driving self-assessment skills introduces an additional factor to be considered in the implementation of these training programs. Copyright © 2012 Elsevier Ltd. All rights reserved.

Investigating the value of time and value of reliability for managed lanes : [summary].

DOT National Transportation Integrated Search

2015-09-01

Managed lanes employ various operational and design strategies to improve highway : efficiency by moving traffic to lanes that are restricted, for example, to drivers with one or : more passengers or to drivers that pay a fee. A drivers decision t...

Post driver for steel guardrail posts : final report.

DOT National Transportation Integrated Search

2003-01-01

The objective of this research project was to locate an existing product, or if necessary, design and develop a product for use as a driver for steel guardrail posts. The post driver would also be able to minimize the bending and twisting of the stee...

Modelling the influence of sensory dynamics on linear and nonlinear driver steering control

NASA Astrophysics Data System (ADS)

Nash, C. J.; Cole, D. J.

2018-05-01

A recent review of the literature has indicated that sensory dynamics play an important role in the driver-vehicle steering task, motivating the design of a new driver model incorporating human sensory systems. This paper presents a full derivation of the linear driver model developed in previous work, and extends the model to control a vehicle with nonlinear tyres. Various nonlinear controllers and state estimators are compared with different approximations of the true system dynamics. The model simulation time is found to increase significantly with the complexity of the controller and state estimator. In general the more complex controllers perform best, although with certain vehicle and tyre models linearised controllers perform as well as a full nonlinear optimisation. Various extended Kalman filters give similar results, although the driver's sensory dynamics reduce control performance compared with full state feedback. The new model could be used to design vehicle systems which interact more naturally and safely with a human driver.

FInal Technical Repot of the Project: Design and Implementation of Low-Power 10Gb/s/channel Laser/Silicon Photonics Modulator Drivers with SEU Tolerance for HL-LHC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gui, Ping

During the funding period of this award from May 1, 2014 through March 30, 2016, we have accomplished the design, implementation and measurement results of two laser driver chips: LpGBLD10+ which is a low-power single-channel 10Gb/s laser driver IC, and LDQ10P, which is a 4x10Gb/s driver array chip for High Energy Physics (HEP) applications. With new circuit techniques, the driver consumes a record-low power consumption, 31 mW @10Gb/s/channel and occupies a small area of 400 µm × 1750 µm for the single-channel driver IC and 1900umx1700um for the LDQ10P chip. These characteristics allow for both the LpGBLD10+ ICs and LDQ10P suitable candidatemore » for the Versatile Link PLUS (VL+) project, offering flexibility in configuring multiple Transmitters and receivers.« less

A randomized trial to evaluate the effectiveness of an individual, education-based safe transport program for drivers aged 75 years and older

PubMed Central

2013-01-01

Background There are concerns over safety of older drivers due to increased crash involvement and vulnerability to injury. However, loss of driving privileges can dramatically reduce independence and quality of life for older members of the community. The aim of this trial is to examine the effectiveness of a safe transport program for drivers aged 75 years and older at reducing driving exposure but maintaining mobility. Methods and design A randomised trial will be conducted, involving 380 drivers aged 75 years and older, resident in urban and semi-rural areas of North-West Sydney. The intervention is an education program based on the Knowledge Enhances Your Safety (KEYS) program, adapted for the Australian context. Driving experience will be measured objectively using an in-vehicle monitoring device which includes a global positioning system (GPS) to assess driving exposure and an accelerometer to detect rapid deceleration events. Participation will be assessed using the Keele Assessment of Participation (KAP). Data will be analysed on an intention-to-treat basis; the primary outcomes include driving exposure, rapid deceleration events and scores for KAP. Secondary outcomes include self-reported measures of driving, socialisation, uptake of alternative forms of transport, depressive symptoms and mood. A detailed process evaluation will be conducted, including examination of the delivery of the program and uptake of alternative forms of transport. A subgroup analysis is planned for drivers with reduced function as characterized by established cut-off scores on the Drivesafe assessment tool. Discussion This randomised trial is powered to provide an objective assessment of the efficacy of an individually tailored education and alternative transportation program to promote safety of older drivers but maintain mobility. Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12612000543886. PMID:23379593

Proposed BISOL Facility - a Conceptual Design

NASA Astrophysics Data System (ADS)

Ye, Yanlin

2018-05-01

In China, a new large-scale nuclear-science research facility, namely the "Beijing Isotope-Separation-On-Line neutron-rich beam facility (BISOL)", has been proposed and reviewed by the governmental committees. This facility aims at both basic science and application goals, and is based on a double-driver concept. On the basic science side, the radioactive ion beams produced from the ISOL device, driven by a research reactor or by an intense deuteron-beam ac- celerator, will be used to study the new physics and technologies at the limit of the nuclear stability in the medium mass region. On the other side regarding to the applications, the facility will be devoted to the material research asso- ciated with the nuclear energy system, by using typically the intense neutron beams produced from the deuteron-accelerator driver. The initial design will be outlined in this report.

Pixel parallel localized driver design for a 128 x 256 pixel array 3D 1Gfps image sensor

NASA Astrophysics Data System (ADS)

Zhang, C.; Dao, V. T. S.; Etoh, T. G.; Charbon, E.

2017-02-01

In this paper, a 3D 1Gfps BSI image sensor is proposed, where 128 × 256 pixels are located in the top-tier chip and a 32 × 32 localized driver array in the bottom-tier chip. Pixels are designed with Multiple Collection Gates (MCG), which collects photons selectively with different collection gates being active at intervals of 1ns to achieve 1Gfps. For the drivers, a global PLL is designed, which consists of a ring oscillator with 6-stage current starved differential inverters, achieving a wide frequency tuning range from 40MHz to 360MHz (20ps rms jitter). The drivers are the replicas of the ring oscillator that operates within a PLL. Together with level shifters and XNOR gates, continuous 3.3V pulses are generated with desired pulse width, which is 1/12 of the PLL clock period. The driver array is activated by a START signal, which propagates through a highly balanced clock tree, to activate all the pixels at the same time with virtually negligible skew.

Fifty years of driving safety research.

PubMed

Lee, John D

2008-06-01

This brief review covers the 50 years of driving-related research published in Human Factors, its contribution to driving safety, and emerging challenges. Many factors affect driving safety, making it difficult to assess the impact of specific factors such as driver age, cell phone distractions, or collision warnings. The author considers the research themes associated with the approximately 270 articles on driving published in Human Factors in the past 50 years. To a large extent, current and past research has explored similar themes and concepts. Many articles published in the first 25 years focused on issues such as driver impairment, individual differences, and perceptual limits. Articles published in the past 25 years address similar issues but also point toward vehicle technology that can exacerbate or mitigate the negative effect of these issues. Conceptual and computational models have played an important role in this research. Improved crash-worthiness has contributed to substantial improvements in driving safety over the past 50 years, but future improvements will depend on enhancing driver performance and perhaps, more important, improving driver behavior. Developing models to guide this research will become more challenging as new technology enters the vehicle and shifts the focus from driver performance to driver behavior. Over the past 50 years, Human Factors has accumulated a large base of driving-related research that remains relevant for many of today's design and policy concerns.

Far-Infrared Based Pedestrian Detection for Driver-Assistance Systems Based on Candidate Filters, Gradient-Based Feature and Multi-Frame Approval Matching

PubMed Central

Wang, Guohua; Liu, Qiong

2015-01-01

Far-infrared pedestrian detection approaches for advanced driver-assistance systems based on high-dimensional features fail to simultaneously achieve robust and real-time detection. We propose a robust and real-time pedestrian detection system characterized by novel candidate filters, novel pedestrian features and multi-frame approval matching in a coarse-to-fine fashion. Firstly, we design two filters based on the pedestrians’ head and the road to select the candidates after applying a pedestrian segmentation algorithm to reduce false alarms. Secondly, we propose a novel feature encapsulating both the relationship of oriented gradient distribution and the code of oriented gradient to deal with the enormous variance in pedestrians’ size and appearance. Thirdly, we introduce a multi-frame approval matching approach utilizing the spatiotemporal continuity of pedestrians to increase the detection rate. Large-scale experiments indicate that the system works in real time and the accuracy has improved about 9% compared with approaches based on high-dimensional features only. PMID:26703611

Far-Infrared Based Pedestrian Detection for Driver-Assistance Systems Based on Candidate Filters, Gradient-Based Feature and Multi-Frame Approval Matching.

PubMed

Wang, Guohua; Liu, Qiong

2015-12-21

Far-infrared pedestrian detection approaches for advanced driver-assistance systems based on high-dimensional features fail to simultaneously achieve robust and real-time detection. We propose a robust and real-time pedestrian detection system characterized by novel candidate filters, novel pedestrian features and multi-frame approval matching in a coarse-to-fine fashion. Firstly, we design two filters based on the pedestrians' head and the road to select the candidates after applying a pedestrian segmentation algorithm to reduce false alarms. Secondly, we propose a novel feature encapsulating both the relationship of oriented gradient distribution and the code of oriented gradient to deal with the enormous variance in pedestrians' size and appearance. Thirdly, we introduce a multi-frame approval matching approach utilizing the spatiotemporal continuity of pedestrians to increase the detection rate. Large-scale experiments indicate that the system works in real time and the accuracy has improved about 9% compared with approaches based on high-dimensional features only.

Improvement of older driver safety through self-evaluation : the development of a self-evaluation instrument

DOT National Transportation Integrated Search

2000-03-01

This research project was designed to increase safety in the older driver population by developing and testing a self-evaluation instrument. The instrument is intended for drivers who may be starting to experience declines in driving abilities or los...

Emergency Vehicle Alarm System for Deaf Drivers by Using LEDs and Vibration Devices

NASA Astrophysics Data System (ADS)

Kuwahara, Noriaki; Morimoto, Kazunari; Kozuki, Kazumasa; Kawamura, Tomonori

We are developing the emergency vehicle alarm system for deaf drivers by using LEDs and vibration devices. In order to design the alarm for deaf drivers, we have conducted basic experiment in order to evaluate perceptual characteristic on visibility of LED.

Meta-Abstract for the EnviroAtlas Poster Block at the 2013 ESRI International User Conference (7/12/13)

EPA Science Inventory

The EPA is launching a web-based mapping application—EnviroAtlas—which is designed to communicate ecosystem services, their drivers, societal benefits, and potential future status in a user-friendly manner. EnviroAtlas includes a coarse-scale national component, with...

Predicting Entrepreneurial Motivation among University Students: The Role of Entrepreneurship Education

ERIC Educational Resources Information Center

Farhangmehr, Minoo; Gonçalves, Paulo; Sarmento, Maria

2016-01-01

Purpose: The purpose of this paper is to better understand the main drivers of entrepreneurial motivation among university students and to determine whether entrepreneurship education has a moderating effect on improving the impact of knowledge base and entrepreneurship competencies on entrepreneurial motivation. Design/methodology/approach: This…

Designing for Quality: The Understanding Dementia MOOC

ERIC Educational Resources Information Center

King, Carolyn; Kelder, Jo-Anne; Doherty, Kathleen; Phillips, Rob; McInerney, Fran; Walls, Justin; Robinson, Andrew; Vickers, James

2014-01-01

The introduction of Massive Open Online Courses (MOOCs) as a vehicle for education delivery presents opportunities and challenges. In the context of the Wicking Dementia Research and Education Centre (Wicking Centre), the driver to develop a MOOC was the promise of addressing the international deficit in evidence-based dementia education, as well…

Integrated vehicle-based safety systems (IVBSS) : human factors and driver-vehicle interface (DVI) summary report

DOT National Transportation Integrated Search

2008-02-01

The IVBSS program is a four-year, two-phase project to design and evaluate an integrated crash warning system for forward collision, lateral drift, lane-change merge, and curve speed warnings for both light vehicles and heavy trucks. This report, cov...

Specifying Software Behavior for Requirements and Design

DTIC Science & Technology

2013-01-01

e.g., Behavior Hiding is comprised of the Function Driver and Shared Services modules. Blacked-out modules, which are concerned with mechanisms for...and Shared Services modules. “The Func- tion Driver Module consists of a set of modules called Func- tion Drivers; each Function Driver is the sole...system environment. Functions that capture the rules determining these output values specify that behavior. The Shared Services module concerns aspects of

Model for understanding consumer textural food choice.

PubMed

Jeltema, Melissa; Beckley, Jacqueline; Vahalik, Jennifer

2015-05-01

The current paradigm for developing products that will match the marketing messaging is flawed because the drivers of product choice and satisfaction based on texture are misunderstood. Qualitative research across 10 years has led to the thesis explored in this research that individuals have a preferred way to manipulate food in their mouths (i.e., mouth behavior) and that this behavior is a major driver of food choice, satisfaction, and the desire to repurchase. Texture, which is currently thought to be a major driver of product choice, is a secondary factor, and is important only in that it supports the primary driver-mouth behavior. A model for mouth behavior is proposed and the qualitative research supporting the identification of different mouth behaviors is presented. The development of a trademarked typing tool for characterizing mouth behavior is described along with quantitative substantiation of the tool's ability to group individuals by mouth behavior. The use of these four groups to understand textural preferences and the implications for a variety of areas including product design and weight management are explored.

Understanding the Linkage between Charging Network Coverage and Charging Opportunity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Changzheng; Lin, Zhenhong; Kontou, Eleftheria

2016-01-01

Using GPS-based travel survey data, this paper estimates the relationship between public charging network coverage and charging opportunity, defined as the probability of being able to access public charging for a driver at one of his/her stops or at one travel day. Understanding this relationship is of important interests to the electric vehicle industry and government in determining appropriate charging infrastructure deployment level and estimating the impact of public charging on market adoption of electric vehicles. The analysis finds that drivers trip destinations concentrate on a few popular places. If top 1% of most popular places are installed with publicmore » chargers, on average, drivers will be able to access public charging at 20% of all their stops and 1/3 of their travel days; If 20% of most popular places are installed with public chargers, drivers will be able to access public charging at 89% of all their stops and 94% of their travel days. These findings are encouraging, implying charging network can be efficiently designed by concentrating at a few popular places while still providing a high level of charging opportunity.« less

Multiple vehicle tracking in aerial video sequence using driver behavior analysis and improved deterministic data association

NASA Astrophysics Data System (ADS)

Zhang, Xunxun; Xu, Hongke; Fang, Jianwu

2018-01-01

Along with the rapid development of the unmanned aerial vehicle technology, multiple vehicle tracking (MVT) in aerial video sequence has received widespread interest for providing the required traffic information. Due to the camera motion and complex background, MVT in aerial video sequence poses unique challenges. We propose an efficient MVT algorithm via driver behavior-based Kalman filter (DBKF) and an improved deterministic data association (IDDA) method. First, a hierarchical image registration method is put forward to compensate the camera motion. Afterward, to improve the accuracy of the state estimation, we propose the DBKF module by incorporating the driver behavior into the Kalman filter, where artificial potential field is introduced to reflect the driver behavior. Then, to implement the data association, a local optimization method is designed instead of global optimization. By introducing the adaptive operating strategy, the proposed IDDA method can also deal with the situation in which the vehicles suddenly appear or disappear. Finally, comprehensive experiments on the DARPA VIVID data set and KIT AIS data set demonstrate that the proposed algorithm can generate satisfactory and superior results.

Use and misuse of automobile child restraint devices.

PubMed

Margolis, L H; Wagenaar, A C; Molnar, L J

1992-03-01

To determine demographic, social, and behavioral characteristics that are associated with correct child restraint device (CRD) use. Cross-sectional. Fast-food restaurant parking lots in southeastern Michigan. Children younger than age 4 years and their drivers. Consecutive sample. None. Seven hundred seventeen child passengers were observed for 11 dimensions of CRD use and 661 of their drivers were interviewed. Three hundred ninety-four (55%) of the children were in CRDs, but 248 (63%) of those children were incorrectly restrained. A 43-point misuse index was constructed based on scores assigned for different types of misuse. Seven variables (ie, age of child, race of parent, driver as a parent, days driving, number of occupants, perceived comfort of CRDs, and belief that the social norm supports CRD use) were highly predictive of CRD use. In contrast, only three factors (ie, age of child, education of the driver, and knowledge of the CRD law) were minimally predictive of correct use. Since correct use of CRDs represents such a complex behavior, the best strategy to address the widespread problem of CRD use may be through the design of less complicated CRDs.

The somatic mutation profiles of 2,433 breast cancers refines their genomic and transcriptomic landscapes

PubMed Central

Pereira, Bernard; Chin, Suet-Feung; Rueda, Oscar M.; Vollan, Hans-Kristian Moen; Provenzano, Elena; Bardwell, Helen A.; Pugh, Michelle; Jones, Linda; Russell, Roslin; Sammut, Stephen-John; Tsui, Dana W. Y.; Liu, Bin; Dawson, Sarah-Jane; Abraham, Jean; Northen, Helen; Peden, John F.; Mukherjee, Abhik; Turashvili, Gulisa; Green, Andrew R.; McKinney, Steve; Oloumi, Arusha; Shah, Sohrab; Rosenfeld, Nitzan; Murphy, Leigh; Bentley, David R.; Ellis, Ian O.; Purushotham, Arnie; Pinder, Sarah E.; Børresen-Dale, Anne-Lise; Earl, Helena M.; Pharoah, Paul D.; Ross, Mark T.; Aparicio, Samuel; Caldas, Carlos

2016-01-01

The genomic landscape of breast cancer is complex, and inter- and intra-tumour heterogeneity are important challenges in treating the disease. In this study, we sequence 173 genes in 2,433 primary breast tumours that have copy number aberration (CNA), gene expression and long-term clinical follow-up data. We identify 40 mutation-driver (Mut-driver) genes, and determine associations between mutations, driver CNA profiles, clinical-pathological parameters and survival. We assess the clonal states of Mut-driver mutations, and estimate levels of intra-tumour heterogeneity using mutant-allele fractions. Associations between PIK3CA mutations and reduced survival are identified in three subgroups of ER-positive cancer (defined by amplification of 17q23, 11q13–14 or 8q24). High levels of intra-tumour heterogeneity are in general associated with a worse outcome, but highly aggressive tumours with 11q13–14 amplification have low levels of intra-tumour heterogeneity. These results emphasize the importance of genome-based stratification of breast cancer, and have important implications for designing therapeutic strategies. PMID:27161491

Assessing contextual factors that influence acceptance of pedestrian alerts by a night vision system.

PubMed

Källhammer, Jan-Erik; Smith, Kip

2012-08-01

We investigated five contextual variables that we hypothesized would influence driver acceptance of alerts to pedestrians issued by a night vision active safety system to inform the specification of the system's alerting strategies. Driver acceptance of automotive active safety systems is a key factor to promote their use and implies a need to assess factors influencing driver acceptance. In a field operational test, 10 drivers drove instrumented vehicles equipped with a preproduction night vision system with pedestrian detection software. In a follow-up experiment, the 10 drivers and 25 additional volunteers without experience with the system watched 57 clips with pedestrian encounters gathered during the field operational test. They rated the acceptance of an alert to each pedestrian encounter. Levels of rating concordance were significant between drivers who experienced the encounters and participants who did not. Two contextual variables, pedestrian location and motion, were found to influence ratings. Alerts were more accepted when pedestrians were close to or moving toward the vehicle's path. The study demonstrates the utility of using subjective driver acceptance ratings to inform the design of active safety systems and to leverage expensive field operational test data within the confines of the laboratory. The design of alerting strategies for active safety systems needs to heed the driver's contextual sensitivity to issued alerts.

The effect of feedback on attitudes toward cellular phone use while driving: a comparison between novice and experienced drivers.

PubMed

Wang, Ying; Zhang, Wei; Reimer, Bryan; Lavallière, Martin; Lesch, Mary F; Horrey, William J; Wu, Su

2010-10-01

To assess and compare the effectiveness of a simulation-based approach to change drivers' attitudes toward cellular phone use while driving for younger novice and older experienced drivers. Thirty young novice drivers were tested on a driving simulator in this study. Their performance in dealing with driving tasks was measured for a single task and dual tasks (driving while using a cellular phone) and compared to 30 older experienced drivers tested previously in another study. Half of the younger drivers received video-based feedback regarding their performance in the two conditions, with an emphasis on the contribution of dual-tasking to degraded performance. The other half did not receive any performance feedback. Drivers' perceptions and attitudes toward cellular phone use while driving were investigated by a questionnaire before, immediately after, and again one month following the simulation-based testing for both groups of drivers (feedback; no feedback). All drivers (including the novice and experienced) reported willingness to engage in driving and talking on a cellular phone in some situations. The simulated driving test showed that a secondary cellular phone task significantly degraded driving performance for both the novice and the experienced drivers. The feedback treatment group (both the novice and the experienced) showed significant attitude change toward cellular phone use while driving (toward being less favorable), whereas the control group had no attitude change. At the one-month follow-up, the benefit of feedback was sustained more so in the experienced driver group than the novice driver group, although both groups still benefited relative to the control conditions. Simulation-based feedback training is promising for short-term education in novice drivers but may be more effective in the long-term for drivers with higher levels of experience. Drivers with more experience appear to have a greater, more sustained benefit from the training than novices. Additional research is needed to better tailor this education method toward novice drivers. Simulation-based participative education approach through feedback needs to be better tailored toward novice drivers.

California's Bus Driver's Training Course. Instructor's Manual.

ERIC Educational Resources Information Center

California State Dept. of Education, Sacramento.

This instructor's manual was designed to help graduates of the California Bus Driver Instructor Course provide effective instruction to school bus driver trainees. It contains enough material for 20-30 hours of classroom training. The information is organized in 12 instructional units that cover the following topics: introduction to the course;…

Westinghouse ICF power plant study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sucov, E. W.

1980-10-01

In this study, two different electric power plants for the production of about 1000 MWe which were based on a CO/sub 2/ laser driver and on a heavy ion driver have been developed and analyzed. The purposes of this study were: (1) to examine in a self consistent way the technological and institutional problems that need to be confronted and solved in order to produce commercially competitive electricity in the 2020 time frame from an inertial fusion reactor, and (2) to compare, on a common basis, the consequences of using two different drivers to initiate the DT fuel pellet explosions.more » Analytic descriptions of size/performance/cost relationships for each of the subsystems comprising the power plant have been combined into an overall computer code which models the entire plant. This overall model has been used to conduct trade studies which examine the consequences of varying critical design values around the reference point.« less

Professional drivers: protection needed for a high-risk occupation.

PubMed Central

Baker, S P; Wong, J; Baron, R D

1976-01-01

"On the job" motor vehicle deaths number more than 4,000 annually in the U.S. and comprise nearly one-third of all work-related deaths. Yet the Department of Labor has set no standards relating to on-the-road safety of the millions of workers whose jobs entail large amounts of driving, and Department of Transportation standards affecting occupational safety cover only drivers in interstate commerce. Drivers of some commercial vehicles, such as heavy trucks, are at special risk of injury because trucks have usually been exempted for many years from federal motor vehicle safety standards--such as standards for brakes and seatbelts--designed to prevent crashes or protect occupants in crashes. Observations based on a series of 150 fatal crashes involving tractor trailers illustrate the need for better protection of this large population of high-risk workers. Clarification of responsibility within the various federal agencies and application of available knowledge and technology are essential. PMID:937611

Using driving simulators to assess driving safety.

PubMed

Boyle, Linda Ng; Lee, John D

2010-05-01

Changes in drivers, vehicles, and roadways pose substantial challenges to the transportation safety community. Crash records and naturalistic driving data are useful for examining the influence of past or existing technology on drivers, and the associations between risk factors and crashes. However, they are limited because causation cannot be established and technology not yet installed in production vehicles cannot be assessed. Driving simulators have become an increasingly widespread tool to understand evolving and novel technologies. The ability to manipulate independent variables in a randomized, controlled setting also provides the added benefit of identifying causal links. This paper introduces a special issue on simulator-based safety studies. The special issue comprises 25 papers that demonstrate the use of driving simulators to address pressing transportation safety problems and includes topics as diverse as neurological dysfunction, work zone design, and driver distraction. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Characterization of low-mass deformable mirrors and ASIC drivers for high-contrast imaging

NASA Astrophysics Data System (ADS)

Mejia Prada, Camilo; Yao, Li; Wu, Yuqian; Roberts, Lewis C.; Shelton, Chris; Wu, Xingtao

2017-09-01

The development of compact, high performance Deformable Mirrors (DMs) is one of the most important technological challenges for high-contrast imaging on space missions. Microscale Inc. has fabricated and characterized piezoelectric stack actuator deformable mirrors (PZT-DMs) and Application-Specific Integrated Circuit (ASIC) drivers for direct integration. The DM-ASIC system is designed to eliminate almost all cables, enabling a very compact optical system with low mass and low power consumption. We report on the optical tests used to evaluate the performance of the DM and ASIC units. We also compare the results to the requirements for space-based high-contrast imaging of exoplanets.

Takeover Time in Highly Automated Vehicles: Noncritical Transitions to and From Manual Control.

PubMed

Eriksson, Alexander; Stanton, Neville A

2017-06-01

The aim of this study was to review existing research into driver control transitions and to determine the time it takes drivers to resume control from a highly automated vehicle in noncritical scenarios. Contemporary research has moved from an inclusive design approach to adhering only to mean/median values when designing control transitions in automated driving. Research into control transitions in highly automated driving has focused on urgent scenarios where drivers are given a relatively short time span to respond to a request to resume manual control. We found a paucity in research into more frequent scenarios for control transitions, such as planned exits from highway systems. Twenty-six drivers drove two scenarios with an automated driving feature activated. Drivers were asked to read a newspaper, or to monitor the system, and to relinquish, or resume, control from the automation when prompted by vehicle systems. Significantly longer control transition times were found between driving with and without secondary tasks. Control transition times were substantially longer than those reported in the peer-reviewed literature. We found that drivers take longer to resume control when under no time pressure compared with that reported in the literature. Moreover, we found that drivers occupied by a secondary task exhibit larger variance and slower responses to requests to resume control. Workload scores implied optimal workload. Intra- and interindividual differences need to be accommodated by vehicle manufacturers and policy makers alike to ensure inclusive design of contemporary systems and safety during control transitions.

What drives technology-based distractions? A structural equation model on social-psychological factors of technology-based driver distraction engagement.

PubMed

Chen, Huei-Yen Winnie; Donmez, Birsen

2016-06-01

With the proliferation of new mobile and in-vehicle technologies, understanding the motivations behind a driver's voluntary engagement with such technologies is crucial from a safety perspective, yet is complex. Previous literature either surveyed a large number of distractions that may be diverse, or too focuses on one particular activity, such as cell phone use. Further, earlier studies about social-psychological factors underlying driver distraction tend to focus on one or two factors in-depth, and those that examine a more comprehensive set of factors are often limited in their analyses methods. The present work considers a wide array of social-psychological factors within a structural equation model to predict their influence on a focused set of technology-based distractions. A better understanding of these facilitators can enhance the design of distraction mitigation strategies. We analysed survey responses about three technology-based driver distractions: holding phone conversations, manually interacting with cell phones, and adjusting the settings of in-vehicle technology, as well as responses on five social-psychological factors: attitude, descriptive norm, injunctive norm, technology inclination, and a risk/sensation seeking personality. Using data collected from 525 drivers (ages: 18-80), a structural equation model was built to analyse these social-psychological factors as latent variables influencing self-reported engagement in these three technology-based distractions. Self-reported engagement in technology-based distractions was found to be largely influenced by attitudes about the distractions. Personality and social norms also played a significant role, but technology inclination did not. A closer look at two age groups (18-30 and 30+) showed that the effect of social norms, especially of injunctive norm (i.e., perceived approvals), was less prominent in the 30+ age group, while personality remained a significant predictor for the 30+ age group but marginally significant for the younger group. Findings from this work provide insights into the social-psychological factors behind intentional engagement in technology-based distractions and in particular suggesting that these factors may be sensitive to demographic differences. Copyright © 2016. Published by Elsevier Ltd.

Driver electronics design and control for a total artificial heart linear motor.

PubMed

Unthan, Kristin; Cuenca-Navalon, Elena; Pelletier, Benedikt; Finocchiaro, Thomas; Steinseifer, Ulrich

2018-01-27

For any implantable device size and efficiency are critical properties. Thus, a linear motor for a Total Artificial Heart was optimized with focus on driver electronics and control strategies. Hardware requirements were defined from power supply and motor setup. Four full bridges were chosen for the power electronics. Shunt resistors were set up for current measurement. Unipolar and bipolar switching for power electronics control were compared regarding current ripple and power losses. Here, unipolar switching showed smaller current ripple and required less power to create the necessary motor forces. Based on calculations for minimal power losses Lorentz force was distributed to the actor's four coils. The distribution was determined as ratio of effective magnetic flux through each coil, which was captured by a force test rig. Static and dynamic measurements under physiological conditions analyzed interaction of control and hardware and all efficiencies were over 89%. In conclusion, the designed electronics, optimized control strategy and applied current distribution create the required motor force and perform optimal under physiological conditions. The developed driver electronics and control offer optimized size and efficiency for any implantable or portable device with multiple independent motor coils. Graphical Abstract ᅟ.

A novel approach to the design of a needle driver with multiple DOFs for pediatric laparoscopic surgery.

PubMed

Fujii, Masahiro; Sugita, Naohiko; Ishimaru, Tetsuya; Iwanaka, Tadashi; Mitsuishi, Mamoru

2013-02-01

The objective of our research was to design and develop a novel needle driver with multiple degrees of freedom (DOFs) for pediatric laparoscopic surgery. Pediatric laparoscopic surgery has many advantages for patients, but the difficulty of the operation is increased due to many restrictions. For example, the motion of the needle driver is restricted by the insertion points, and the operation workspace is smaller in children than in adults. A needle driver with 3 DOFs and a 3.5-mm diameter is proposed and implemented in this study. Grasping DOF is achieved using a piston mechanism actuated by a wire. Deflection and rotation DOFs are actuated by gears. Experiments were conducted to evaluate the workspace and ligation force, and the results confirmed that the needle driver meets all the necessary requirements. Finally, a first reaction of a pediatric surgeon on the suturing and ligaturing capabilities of the prototype is reported. A multi-DOF needle driver with a new mechanism was proposed for pediatric laparoscopic surgery and a first prototype was developed. It is expected that further elaboration of the developed first prototype of the needle driver may contribute to the advancement of pediatric laparoscopic surgery.

Beam wavefront and farfield control for ICF laser driver

NASA Astrophysics Data System (ADS)

Dai, Wanjun; Deng, Wu; Zhang, Xin; Jiang, Xuejun; Zhang, Kun; Zhou, Wei; Zhao, Junpu; Hu, Dongxia

2010-10-01

Five main problems of beam wavefront and farfield control in ICF laser driver are synthetically discussed, including control requirements, beam propagation principle, distortions source control, system design and adjustment optimization, active wavefront correction technology. We demonstrate that beam can be propagated well and the divergence angle of the TIL pulses can be improved to less than 60μrad with solving these problems, which meets the requirements of TIL. The results can provide theoretical and experimental support for wavefront and farfield control designing requirements of the next large scale ICF driver.

Low Cost, Low Complexity Sensor Design for Non-Cooperative Geolocation via Received Signal Strength

DTIC Science & Technology

2012-03-01

6 IOT&E Initial Operational Test and Evaluation . . . . . . . . . . 6 LBS Location - Based Services . . . . . . . . . . . . . . . . . . . 6 LOS Line-of...subscribers. Location - Based Services (LBS) are poised to become a significant growth driver for the US wireless industry. While deployments have been slow...Markets”. PELOUS Group, NJ, Tech. Rep., 2001. 9. “Wi-Fi Location - Based Services (4.1 Desing Guidie)”, May 2008. URL http: //www.cisco.com/en/US/docs

Investigating cognitive ability and self-reported driving performance of post-stroke adults in a driving simulator.

PubMed

Blane, Alison; Falkmer, Torbjörn; Lee, Hoe C; Dukic Willstrand, Tania

2018-01-01

Background Safe driving is a complex activity that requires calibration. This means the driver can accurately assess the level of task demand required for task completion and can accurately evaluate their driving capability. There is much debate on the calibration ability of post-stroke drivers. Objectives The aim of this study was to assess the cognition, self-rated performance, and estimation of task demand in a driving simulator with post-stroke drivers and controls. Methods A between-groups study design was employed, which included a post-stroke driver group and a group of similarly aged older control drivers. Both groups were observed driving in two simulator-based driving scenarios and asked to complete the NASA Task Load Index (TLX) to assess their perceived task demand and self-rate their driving performance. Participants also completed a battery of psychometric tasks to assess attention and executive function, which was used to determine whether post-stroke cognitive impairment impacted on calibration. Results There was no difference in the amount of perceived task demand required to complete the driving task. Despite impairments in cognition, the post-stroke drivers were not more likely to over-estimate their driving abilities than controls. On average, the post-stroke drivers self-rated themselves more poorly than the controls and this rating was related to cognitive ability. Conclusion This study suggests that post-stroke drivers may be aware of their deficits and adjust their driving behavior. Furthermore, using self-performance measures alongside a driving simulator and cognitive assessments may provide complementary fitness-to-drive assessments, as well as rehabilitation tools during post-stroke recovery.

The risk of a safety-critical event associated with mobile device use in specific driving contexts.

PubMed

Fitch, Gregory M; Hanowski, Richard J; Guo, Feng

2015-01-01

We explored drivers' mobile device use and its associated risk of a safety-critical event (SCE) in specific driving contexts. Our premise was that the SCE risk associated with mobile device use increases when the driving task becomes demanding. Data from naturalistic driving studies involving commercial motor vehicle drivers and light vehicle drivers were partitioned into subsets representative of specific driving contexts. The subsets were generated using data set attributes that included level of service and relation to junction. These attributes were selected based on exogenous factors known to alter driving task demands. The subsets were analyzed using a case-cohort approach, which was selected to complement previous investigations of mobile device SCE risk using naturalistic driving data. Both commercial motor vehicle and light vehicle drivers varied as to how much they conversed on a mobile device but did not vary their engagement in visual-manual subtasks. Furthermore, commercial motor vehicle drivers conversed less frequently as the driving task demands increased, whereas light vehicle drivers did not. The risk of an SCE associated with mobile device use was dependent on the subtask performed and the driving context. Only visual-manual subtasks were associated with an increased SCE risk, whereas conversing was associated with a decreased risk in some driving contexts. Drivers' engagement in mobile device subtasks varies by driving context. The SCE risk associated with mobile device use is dependent on the types of subtasks performed and the driving context. The findings of this exploratory study can be applied to the design of driver-vehicle interfaces that mitigate distraction by preventing visual-manual subtasks while driving.

Effect of Maryland's 2011 Alcohol Sales Tax Increase on Alcohol-Positive Driving.

PubMed

Lavoie, Marie-Claude; Langenberg, Patricia; Villaveces, Andres; Dischinger, Patricia C; Simoni-Wastila, Linda; Hoke, Kathleen; Smith, Gordon S

2017-07-01

The 2011 Maryland alcohol sales tax increase from 6% to 9% provided an opportunity to evaluate the impact on rates of alcohol-positive drivers involved in injury crashes. Maryland police crash reports from 2001 to 2013 were analyzed using an interrupted time series design and a multivariable analysis employing generalized estimating equations models with a negative binomial distribution. Data were analyzed in 2014-2015. There was a significant gradual annual reduction of 6% in the population-based rate of all alcohol-positive drivers (p<0.03), and a 12% reduction for drivers aged 15-20 years (p<0.007), and 21-34 years (p<0.001) following the alcohol sales tax increase. There were no significant changes in rates of alcohol-positive drivers aged 35-54 years (rate ratio, 0.98; 95% CI=0.89, 1.09). Drivers aged ≥55 years had a significant immediate 10% increase in the rate of alcohol-positive drivers (rate ratio, 1.10; 95% CI=1.04, 1.16) and a gradual increase of 4.8% per year after the intervention. Models using different denominators and controlling for multiple factors including a proxy for unmeasured factors found similar results overall. The 2011 Maryland alcohol sales tax increase led to a significant reduction in the rate of all alcohol-positive drivers involved in injury crashes especially among drivers aged 15-34 years. This is the first study to examine the impact of alcohol sales taxes on crashes; previous research focused on excise tax. Increasing alcohol taxes is an important but often neglected intervention to reduce alcohol-impaired driving. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Design and construction of the X-2 two-stage free piston driven expansion tube

NASA Technical Reports Server (NTRS)

Doolan, Con

1995-01-01

This report outlines the design and construction of the X-2 two-stage free piston driven expansion tube. The project has completed its construction phase and the facility has been installed in the new impulsive research laboratory where commissioning is about to take place. The X-2 uses a unique, two-stage driver design which allows a more compact and lower overall cost free piston compressor. The new facility has been constructed in order to examine the performance envelope of the two-stage driver and how well it couple to sub-orbital and super-orbital expansion tubes. Data obtained from these experiments will be used for the design of a much larger facility, X-3, utilizing the same free piston driver concept.

Designing for auto safety

NASA Technical Reports Server (NTRS)

Driver, E. T.

1971-01-01

Safety design features in the motor vehicle and highway construction fields result from systems analysis approach to prevent or lessen death, injury, and property damage results. Systems analysis considers the prevention of crashes, increased survivability in crashes, and prompt medical attention to injuries as well as other postcrash salvage measures. The interface of these system elements with the driver, the vehicle, and the environment shows that action on the vehicle system produces the greatest safety payoff through design modifications. New and amended safety standards developed through hazard analysis technique improved accident statistics in the 70'; these regulations include driver qualifications and countermeasures to identify the chronic drunken driver who is involved in more than two-thirds of all auto deaths.

The role of illicit, licit, and designer drugs in the traffic in Hungary.

PubMed

Institóris, László; Hidvégi, Előd; Dobos, Adrienn; Sija, Éva; Kereszty, Éva M; Tajti, László Balázs; Somogyi, Gábor Pál; Varga, Tibor

2017-06-01

The aim of this study was to investigate the prevalence and pattern of psychoactive substances among suspected DUID (Driving Under the Influence of Drugs) drivers in Hungary in 2014 and 2015. Blood and/or urine samples of 1252 suspected drivers (600 in 2014 and 652 in 2015) were analyzed for classical illicit and licit drugs, stimulant designer drugs (SDDs), and for synthetic cannabinoids, with 78.3% and 79.6% positive cases for at least one substance in 2014, and 2015, respectively. Impairment was proven in 39.2% (2014) and 35.7% (2015) of all drivers tested, based on the legal criteria of Hungary. Classical illicit drugs were found to be present in blood or urine of 89-61%, drivers tested. Drivers also tested positive for legal medications in 20-22%, SDDs in 21-28%, and synthetic cannabinoids in 15-19% of all cases. This indicates a drop in prevalence for classical illicit drugs and a slight but statistically non-significant increase for the other three substance groups. The distribution of drug types in each category were: [1] classical illicit drugs: cannabis (432), amphetamine (321), and cocaine (79); [2] medicines: alprazolam (94) and clonazepam (36); [3] SDDs: pentedrone (137) and α-PVP (33); [4] synthetic cannabinoids: AB-CHMINACA (46) and MDMB-CHMICA (30). The average age of illicit drug and SDD users was 30 years, while legal medications users were 36 years old on average, and the mean age of synthetic cannabinoid users was 26.5 years. The presence of both alcohol and at least one drug in samples was found in about 10% of the cases, both years. The ratio of multi-drug use was 33.0% in 2014 and 41.3% in 2015. Compared to former years the number of drivers who tested positive for drugs doubled in Hungary, but it is still low compared to alcohol positive cases. The relatively low detected rate of DUID can be explained by (1) combined alcohol consumption masking drug symptoms, (2) the absence of road-side tests for illicit and designer drugs and, (3) police officers not adequately trained to recognize milder symptoms of impairment. Targeted education of police officers, prompt medical examination and the use of a symptom-focused on-site survey, could improve the efficacy of DUID investigations. Our findings are not comparable with drug consumption habits of the general driving population. The last roadside survey (DRUID EU-6 Project) was performed in Hungary in 2008-2009, prior to the mass spreading of designer drugs. As their appearance has drastically changed the pattern of drug consumption of the population, a new roadside survey, targeting general drivers, would be necessary. Copyright © 2017 Elsevier B.V. All rights reserved.

Driver sleepiness and risk of serious injury to car occupants: population based case control study

PubMed Central

Connor, Jennie; Norton, Robyn; Ameratunga, Shanthi; Robinson, Elizabeth; Civil, Ian; Dunn, Roger; Bailey, John; Jackson, Rod

2002-01-01

Objectives To estimate the contribution of driver sleepiness to the causes of car crash injuries. Design Population based case control study. Setting Auckland region of New Zealand, April 1998 to July 1999. Participants 571 car drivers involved in crashes where at least one occupant was admitted to hospital or killed (“injury crash”); 588 car drivers recruited while driving on public roads (controls), representative of all time spent driving in the study region during the study period. Main outcome measures Relative risk for injury crash associated with driver characteristics related to sleep, and the population attributable risk for driver sleepiness. Results There was a strong association between measures of acute sleepiness and the risk of an injury crash. After adjustment for major confounders significantly increased risk was associated with drivers who identified themselves as sleepy (Stanford sleepiness score 4-7 v 1-3; odds ratio 8.2, 95% confidence interval 3.4 to 19.7); with drivers who reported five hours or less of sleep in the previous 24 hours compared with more than five hours (2.7, 1.4 to 5.4); and with driving between 2 am and 5 am compared with other times of day (5.6, 1.4 to 22.7). No increase in risk was associated with measures of chronic sleepiness. The population attributable risk for driving with one or more of the acute sleepiness risk factors was 19% (15% to 25%). Conclusions Acute sleepiness in car drivers significantly increases the risk of a crash in which a car occupant is injured or killed. Reductions in road traffic injuries may be achieved if fewer people drive when they are sleepy or have been deprived of sleep or drive between 2 am and 5 am. What is already known on this topicDriver sleepiness is considered a potentially important risk factor for car crashes and related injuries but the association has not been reliably quantifiedPublished estimates of the proportion of car crashes attributable to driver sleepiness vary from about 3% to 30%What this study addsDriving while feeling sleepy, driving after five hours or less of sleep, and driving between 2 am and 5 am were associated with a substantial increase in the risk of a car crash resulting in serious injury or deathReduction in the prevalence of these three behaviours may reduce the incidence of injury crashes by up to 19% PMID:12003884

A Study of Alcohol Use by Designated Drivers among College Students

ERIC Educational Resources Information Center

Dermody, Sarah S.; Cheong, JeeWon; Walther, Christine A.

2012-01-01

Objective: College students tend to drink while serving as a designated driver (DD). The predictors of alcohol use by DDs among college students were examined. Participants: Participants were 119 undergraduate students in introductory psychology courses who had experience with DD use. Methods: Survey data were analyzed to examine the predictors of…

Evaluation of a Local Designated Driver and Responsible Server Program to Prevent Drinking and Driving.

ERIC Educational Resources Information Center

Simons-Morton, Bruce G.; Cummings, Sharon Snider

1997-01-01

Evaluates the impact of beverage servers' interventions at five establishments participating in the Houston Techniques for Effective Alcohol Management (TEAM) program. The intervention included server training, a designated-driver program, and "Safe Ride Home" taxi vouchers. Findings are discussed within the context of scant public and…

Prevalence of sleep-related accidents among drivers in Saudi Arabia

PubMed Central

BaHammam, Ahmad S.; Alkhunizan, Muath A.; Lesloum, Rabea H.; Alshanqiti, Amer M.; Aldakhil, Abdulrahman M.; Pandi-Perumal, Seithikurippu R.; Sharif, Munir M.

2014-01-01

INTRODUCTION: The prevalence of sleepy driving and sleep-related accidents (SRA) varies widely, and no data exist regarding the prevalence of sleepy driving in Saudi Arabia. Therefore, this study was designed to determine the prevalence and predictors of sleepy driving, near-misses, and SRA among drivers in Saudi Arabia. MATERIALS AND METHODS: A questionnaire was developed to assess sleep and driving in detail based on previously published data regarding sleepy driving. The questionnaire included 50 questions addressing socio-demographics, the Epworth Sleepiness Scale (ESS), driving items, and the Berlin Questionnaire. In total, 1,219 male drivers in public places were interviewed face-to-face. RESULTS: The included drivers had a mean age of 32.4 ± 11.7 years and displayed a mean ESS score of 7.2 ± 3.8. Among these drivers, 33.1% reported at least one near-miss accident caused by sleepiness. Among those who had actual accidents, 11.6% were attributed to sleepiness. In the past six months, drivers reported the following: 25.2% reported falling asleep at least once during, driving and 20.8% had to stop driving at least once because of severe sleepiness. Young age, feeling very sleepy during driving, and having at least one near-miss accident caused by sleepiness in the past six months were the only predictors of accidents. CONCLUSION: Sleepy driving is prevalent among male drivers in Saudi Arabia. Near-miss accidents caused by sleepiness are an important risk factor for car accidents and should be considered as a strong warning signal of future accidents. PMID:25276244

TARDEC FIXED HEEL POINT (FHP): DRIVER CAD ACCOMMODATION MODEL VERIFICATION REPORT

DTIC Science & Technology

2017-11-09

SUPPLEMENTARY NOTES N/A 14. ABSTRACT Easy-to-use Computer-Aided Design (CAD) tools, known as accommodation models, are needed by the ground vehicle... designers when developing the interior workspace for the occupant. The TARDEC Fixed Heel Point (FHP): Driver CAD Accommodation Model described in this...is intended to provide the composite boundaries representing the body of the defined target design population, including posture prediction

Training Manual: Driver Education. Vocational Strategies for Special Needs Students.

ERIC Educational Resources Information Center

Blanc, Doreen V.

Lessons presented in this manual, developed as part of the vocational strategies project, are designed to provide driver education for mildly handicapped special needs students placed in jobs that require a driver's license. The guide is intended for use in conjunction with a vocational program in automotive mechanics, or integrated into a…

Driving Procedures. A Resource Guide for Driver Education Teachers.

ERIC Educational Resources Information Center

Texas State Dept. of Public Safety, Austin.

Designed to provide instructors with resource materials for driver education, this book contains mainly materials on established safe driving procedures. An introduction defines a procedure as describing ways in which a driver can comply with the law to do something extra that will increase his/her safety and prevent congestion and collision.…

Development of high precision digital driver of acoustic-optical frequency shifter for ROG

NASA Astrophysics Data System (ADS)

Zhang, Rong; Kong, Mei; Xu, Yameng

2016-10-01

We develop a high precision digital driver of the acoustic-optical frequency shifter (AOFS) based on the parallel direct digital synthesizer (DDS) technology. We use an atomic clock as the phase-locked loop (PLL) reference clock, and the PLL is realized by a dual digital phase-locked loop. A DDS sampling clock up to 320 MHz with a frequency stability as low as 10-12 Hz is obtained. By constructing the RF signal measurement system, it is measured that the frequency output range of the AOFS-driver is 52-58 MHz, the center frequency of the band-pass filter is 55 MHz, the ripple in the band is less than 1 dB@3MHz, the single channel output power is up to 0.3 W, the frequency stability is 1 ppb (1 hour duration), and the frequency-shift precision is 0.1 Hz. The obtained frequency stability has two orders of improvement compared to that of the analog AOFS-drivers. For the designed binary frequency shift keying (2-FSK) and binary phase shift keying (2-PSK) modulation system, the demodulating frequency of the input TTL synchronous level signal is up to 10 kHz. The designed digital-bus coding/decoding system is compatible with many conventional digital bus protocols. It can interface with the ROG signal detecting software through the integrated drive electronics (IDE) and exchange data with the two DDS frequency-shift channels through the signal detecting software.

Survey of health and licensing policies for taxi drivers in Singapore, Hong Kong and Australia: a perspective from evidence on older drivers.

PubMed

Chan, M L; Gustafsson, L; Liddle, J

2010-12-01

With an ageing population, policy makers need to balance active ageing needs with older driver safety. In 2009, a survey of licensing policies for taxi drivers in Singapore, Hong Kong and Australia was undertaken for an evidence-based review of policies. Licensing requirements collected using semi-structured questionnaires were compared descriptively and with evidence from licensing policies on older drivers. All the regions used medical certifications with vision screening. The frequency of medical certification varied according to the renewal cycle and age. Medical guidelines on fitness to drive were available in Australia and Singapore. Legislation for self-reporting of medical conditions by drivers existed in Australia and Hong Kong. Legislation for reporting at-risk drivers by doctors was limited to two Australian states. There were differences in the minimum age and driving experience criteria, the use of practical training, written and English tests, age-based screening, mandatory retirement age, refresher courses, off- and on-road tests. Medical screening for at-risk drivers remains crucial. Age-based mandatory retirement policy at 73 years in Singapore is contrary to evidence-based practice. The lack of legislation for self-reporting of illness by drivers, the high minimum age criteria and therapy driving assessments for healthy taxi drivers are also unique to Singapore. There was stricter age-based relicensing from the age of 65 years in some Australian states and in Singapore. Continuing education for doctors, multi-tier screening for at-risk drivers and licensing policy changes are indicated.

Improving socket design to prevent difficult removal of locking screws.

PubMed

Lin, Chen-Huei; Chao, Ching-Kong; Tang, Yi-Hsuan; Lin, Jinn

2018-03-01

Reports of driver slippage leading to difficult locking screw removals have increased since the adoption of titanium for screw fabrication; the use of titanium is known to cause cross-threading and cold welding. Such problems occur most frequently in screws with hex sockets, and may cause serious surgical complications. This study aimed to improve screw socket design to prevent slippage and difficult screw removal. Three types of small sockets (hex, Torx, and cruciate) and six types of large sockets (hex, Torx, Octatorx, Torx+ I, Torx+ II, and Torx+ III) with screw head diameters of 5.5 mm were manufactured from titanium, and corresponding screwdrivers were manufactured from stainless steel. The screw heads and drivers were mounted on a material testing machine, and torsional tests were conducted to simulate screw usage in clinical settings at two insertion depths: 1 and 2 mm. Ten specimens were tested from each design, and the maximum torque and failure patterns were recorded and compared. For small sockets in 2 mm conditions, the hex with the largest driver core had the highest torque, followed by Torx and cruciate. In these tests, the drivers were twisted off in all specimens. However, under the 1 mm condition, the hex slipped and the torque decreased markedly. Overall, torque was higher for large sockets than for small sockets. The Octatorx, with a large core and simultaneous deformation of the driver and socket lobes, had the highest torque at almost twice that of the small hex. The hex had the lowest torque, a result of slippage in both the 1 and 2 mm conditions. Torx plus designs, with more designed degrees of freedom, were able to maintain a higher driving angle and larger core for higher torque. The hex design showed slipping tendencies with a marked decrease in torque, especially under conditions with inadequate driver engagement. Large sockets allowed for substantial increases in torque. The Torx, Octatorx, and Torx plus designs displayed better performance than the hexes. Improvements to the socket design could effectively prevent slippage and solve difficult screw removal problems. Copyright © 2018. Published by Elsevier Ltd.

Optimization of robustness of interdependent network controllability by redundant design

PubMed Central

2018-01-01

Controllability of complex networks has been a hot topic in recent years. Real networks regarded as interdependent networks are always coupled together by multiple networks. The cascading process of interdependent networks including interdependent failure and overload failure will destroy the robustness of controllability for the whole network. Therefore, the optimization of the robustness of interdependent network controllability is of great importance in the research area of complex networks. In this paper, based on the model of interdependent networks constructed first, we determine the cascading process under different proportions of node attacks. Then, the structural controllability of interdependent networks is measured by the minimum driver nodes. Furthermore, we propose a parameter which can be obtained by the structure and minimum driver set of interdependent networks under different proportions of node attacks and analyze the robustness for interdependent network controllability. Finally, we optimize the robustness of interdependent network controllability by redundant design including node backup and redundancy edge backup and improve the redundant design by proposing different strategies according to their cost. Comparative strategies of redundant design are conducted to find the best strategy. Results shows that node backup and redundancy edge backup can indeed decrease those nodes suffering from failure and improve the robustness of controllability. Considering the cost of redundant design, we should choose BBS (betweenness-based strategy) or DBS (degree based strategy) for node backup and HDF(high degree first) for redundancy edge backup. Above all, our proposed strategies are feasible and effective at improving the robustness of interdependent network controllability. PMID:29438426

Driving simulator evaluation of drivers' response to intersections with dynamic use of exit-lanes for left-turn.

PubMed

Zhao, Jing; Yun, Meiping; Zhang, H Michael; Yang, Xiaoguang

2015-08-01

With the worsening of urban traffic congestion in large cities around the world, researchers have been looking for unconventional designs and/or controls to squeeze more capacity out of intersections, the most common bottlenecks of the road network. One of these innovative intersection designs, known as the exit-lanes for left-turn (EFL), opens up exit-lanes to be used by left-turn traffic with the help of an additional traffic light installed at the median opening (the pre-signal). This paper studies how drivers respond to EFL intersections with a series of driving simulator experiments. In our experiments, 64 drivers were recruited and divided into two groups. One group is trained to use the EFL while the other group is not. In addition, four scenarios were considered with different sign and marking designs and traffic conditions in the experiments. Results indicate that drivers show certain amount of confusion and hesitation when encountering an EFL intersection for the first time. They can be overcome, however, by increasing exposure through driver education or by cue provided from other vehicles. Moreover, drivers unfamiliar with EFL operation can make a left turn using the conventional left-turn lanes as usual. The EFL operation is not likely to pose any serious safety risk of the intersection in real life operations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Using Pair Programming to Teach CAD Based Engineering Graphics

ERIC Educational Resources Information Center

Leland, Robert P.

2010-01-01

Pair programming was introduced into a course in engineering graphics that emphasizes solid modeling using SolidWorks. In pair programming, two students work at a single computer, and periodically trade off roles as driver (hands on the keyboard and mouse) and navigator (discuss strategy and design issues). Pair programming was used in a design…

What Makes Your Wheels Turn?

ERIC Educational Resources Information Center

DiJulio, Betsy

2010-01-01

In the author's ongoing attempt to design creative challenges that are relevant, based on observational drawing, and that place students squarely in the creative problem-solving driver's seat, she chose cars and engines as subjects. After all, they have a parking lot full of them and their administrative staff members, who park side-by-side, were…

Design of DroDeASys (Drowsy Detection and Alarming System)

NASA Astrophysics Data System (ADS)

Juvale, Hrishikesh B.; Mahajan, Anant S.; Bhagwat, Ashwin A.; Badiger, Vishal T.; Bhutkar, Ganesh D.; Dhabe, Priyadarshan S.; Dhore, Manikrao L.

The paper discusses the Drowsy Detection & Alarming System that has been developed, using a non-intrusive approach. The system is basically developed to detect drivers dozing at the wheel at night time driving. The system uses a small infra-red night vision camera that points directly towards the driver`s face and monitors the driver`s eyes in order to detect fatigue. In such a case when fatigue is detected, a warning signal is issued to alert the driver. This paper discusses the algorithms that have been used to detect drowsiness. The decision whether the driver is dozing or not is taken depending on whether the eyes are open for a specific number of frames. If the eyes are found to be closed for a certain number of consecutive frames then the driver is alerted with an alarm.

Operations Assessment of Launch Vehicle Architectures using Activity Based Cost Models

NASA Technical Reports Server (NTRS)

Ruiz-Torres, Alex J.; McCleskey, Carey

2000-01-01

The growing emphasis on affordability for space transportation systems requires the assessment of new space vehicles for all life cycle activities, from design and development, through manufacturing and operations. This paper addresses the operational assessment of launch vehicles, focusing on modeling the ground support requirements of a vehicle architecture, and estimating the resulting costs and flight rate. This paper proposes the use of Activity Based Costing (ABC) modeling for this assessment. The model uses expert knowledge to determine the activities, the activity times and the activity costs based on vehicle design characteristics. The approach provides several advantages to current approaches to vehicle architecture assessment including easier validation and allowing vehicle designers to understand the cost and cycle time drivers.

The ironies of vehicle feedback in car design.

PubMed

Walker, Guy H; Stanton, Neville A; Young, Mark S

2006-02-10

Car drivers show an acute sensitivity towards vehicle feedback, with most normal drivers able to detect 'the difference in vehicle feel of a medium-size saloon car with and without a fairly heavy passenger in the rear seat' (Joy and Hartley 1953-54). The irony is that this level of sensitivity stands in contrast to the significant changes in vehicle 'feel' accompanying modern trends in automotive design, such as drive-by-wire and increased automation. The aim of this paper is to move the debate from the anecdotal to the scientific level. This is achieved by using the Brunel University driving simulator to replicate some of these trends and changes by presenting (or removing) different forms of non-visual vehicle feedback, and measuring resultant driver situational awareness (SA) using a probe-recall method. The findings confirm that vehicle feedback plays a key role in coupling the driver to the dynamics of their environment (Moray 2004), with the role of auditory feedback particularly prominent. As a contrast, drivers in the study also rated their self-perceived levels of SA and a concerning dissociation occurred between the two sets of results. Despite the large changes in vehicle feedback presented in the simulator, and the measured changes in SA, drivers appeared to have little self-awareness of these changes. Most worryingly, drivers demonstrated little awareness of diminished SA. The issues surrounding vehicle feedback are therefore similar to the classic problems and ironies studied in aviation and automation, and highlight the role that ergonomics can also play within the domain of contemporary vehicle design.

Driver performance and attention allocation in use of logo signs on freeway exit ramps.

PubMed

Zahabi, Maryam; Machado, Patricia; Lau, Mei Ying; Deng, Yulin; Pankok, Carl; Hummer, Joseph; Rasdorf, William; Kaber, David B

2017-11-01

The objective of this research was to quantify the effects of driver age, ramp signage configuration, including number of panels, logo format and sign familiarity, on driver performance and attention allocation when exiting freeways. Sixty drivers participated in a simulator study and analysis of variance models were used to assess response effects of the controlled manipulations. Results revealed elderly drivers to demonstrate worse performance and conservative control strategies as compared to middle-aged and young drivers. Elderly drivers also exhibited lower off-road fixation frequency and shorter off-road glance durations compared to middle-aged and young drivers. In general, drivers adopted a more conservative strategy when exposed to nine-panel signs as compared to six-panel signs and were more accurate in target detection when searching six-panels vs. nine and with familiar vs. unfamiliar logos. These findings provide an applicable guide for agency design of freeway ramp signage accounting for driver demographics. Copyright © 2017 Elsevier Ltd. All rights reserved.

A fuzzy gear shifting strategy for manual transmissions

NASA Astrophysics Data System (ADS)

Mashadi, B.; Kazemkhani, A.

2005-12-01

Governing parameters in decision making for gear changing of an automated manual transmission are discussed based on two different criteria, namely engine working conditions and driver's intention. By taking into consideration the effects of these parameters, gear shifting strategy is designed with the application of Fuzzy control method. The controller structure is formed in two layers. In the first layer two fuzzy inference modules are used to determine necessary outputs. In second layer a fuzzy inference module makes the decision of shifting by up-shift, downshift or maintain commands. The quality of Fuzzy controller behavior is examined by making use of ADVISOR software. It is shown that at different driving conditions the controller makes correct decisions for gear shifting accounting for dynamical requirements of vehicle. It is also shown that the controller based on both engine state and driver's intention eliminates unnecessary shiftings that are present when the intention is ignored. A micro-trip is designed in which a required speed in the form of a step function is demanded for the vehicle. Starting from rest both strategies change the gear to reach maximum speed more or less in a similar fashion. In deceleration phase, however, large differences are observed between the two strategies. The engine-state strategy is less sensitive to downshift, taking even unnecessary up shift decisions. The state-intention strategy, however, correctly interprets the driver's intention for decreasing speed and utilizes engine brake torque to reduce vehicle speed in a shorter time.

The Balsa bullet: A high speed, low-cost general aviation aircraft for Aeroworld

NASA Technical Reports Server (NTRS)

Eastland, Kevin; Greenwood, Sean; Kelly, Dan; Leonard, Chuck; Rooff, John; Scherock, Jeff

1994-01-01

The Balsa Bullet is a high speed, low cost six passenger general aviation aircraft. It will cruise at a speed of 55 ft/s with a maximum speed of 75 ft/s for distances in excess of 27000 feet. This range and speed combination provide The Balsa Bullet with the capability to service any two existing airports in Aeroworld in an efficient and timely manner. Overall, three major design drivers have been identified by the design team. The first is to provide a low cost airplane to the Aeroworld market. Maintaining the low cost objective will not simply meet the mission objective, but will also make the Bullet an economically viable option for a wide number of consumers. The Balsa Bullet has a total manufacturing cost of $1000 with a price to the consumer of only $2562. The second major driver is high speed performance. Once again this driver exists not only to meet the mission objective given Long Shot Aeronautics but it provides a desirable feature to the consumer, pride in owning the fastest aircraft in Aeroworld. The third design driver identified is the capability to service any runway in Aeroworld necessitating the ability to takeoff within 28 ft, the length of the shortest runways in Aeroworld. These design drivers provide three great reasons for the general public to purchase a Bullet.

3D Printed Fluidic Hardware for DNA Assembly

DTIC Science & Technology

2015-04-10

A3909 stepper motor driver, were soldered onto the milled circuit board (Supplementary Figure 8). Custom Arduino - based firmware was written to take...initiatives such as the FabLab Foundation10. Access to digital fabrication tools and open electronics, such as Arduino and Raspberry Pi, enables access to...hardware for assembly of DNA- based genetic circuits. Solid-phase DNA synthesis has declined in price, enabling researchers to routinely design and

RF Bearing Estimation in Wireless Sensor Networks

DTIC Science & Technology

2010-01-01

are the main design drivers. Techniques based on ultrasonic and infrared signal modalities have short range and require line-of-sight. Clearly, RF...generating a Doppler shifted RF signal . The small frequency change can be measured even on low cost resource constrained nodes using a radio...is already included in the power budget and RF range is superior to most other signals . Radio signal strength (RSS) based approaches are the most

A programmable CCD driver circuit for multiphase CCD operation

NASA Technical Reports Server (NTRS)

Ewin, Audrey J.; Reed, Kenneth V.

1989-01-01

A programmable CCD (charge-coupled device) driver circuit was designed to drive CCDs in multiphased modes. The purpose of the drive electronics is to operate developmental CCD imaging arrays for NASA's tiltable moderate resolution imaging spectrometer (MODIS-T). Five objectives for the driver were considered during its design: (1) the circuit drives CCD electrode voltages between 0 V and +30 V to produce reasonable potential wells, (2) the driving sequence is started with one input signal, (3) the driving sequence is started with one input signal, (4) the circuit allows programming of frame sequences required by arrays of any size, (5) it produces interfacing signals for the CCD and the DTF (detector test facility). Simulation of the driver verified its function with the master clock running up to 10 MHz. This suggests a maximum rate of 400,000 pixels/s. Timing and packaging parameters were verified. The design uses 54 TTL (transistor-transistor logic) chips. Two versions of hardware were fabricated: wirewrap and printed circuit board. Both were verified functionally with a logic analyzer.

Flip-chip bonded optoelectronic integration based on ultrathin silicon (UTSi) CMOS

NASA Astrophysics Data System (ADS)

Hong, Sunkwang; Ho, Tawei; Zhang, Liping; Sawchuk, Alexander A.

2003-06-01

We describe the design and test of flip-chip bonded optoelectronic CMOS devices based on Peregrine Semiconductor's 0.5 micron Ultra-Thin Silicon on sapphire (UTSi) technology. The UTSi process eliminates the substrate leakage that typically results in crosstalk and reduces parasitic capacitance to the substrate, providing many benefits compared to bulk silicon CMOS. The low-loss synthetic sapphire substrate is optically transparent and has a coefficient of thermal expansion suitable for flip-chip bonding of vertical cavity surface emitting lasers (VCSELs) and detectors. We have designed two different UTSi CMOS chips. One contains a flip-chip bonded 1 x 4 photodiode array, a receiver array, a double edge triggered D-flip flop-based 2047-pattern pseudo random bit stream (PRBS) generator and a quadrature-phase LC-voltage controlled oscillator (VCO). The other chip contains a flip-chip bonded 1 x 4 VCSEL array, a driver array based on high-speed low-voltage differential signals (LVDS) and a full-balanced differential LC-VCO. Each VCSEL driver and receiver has individual input and bias voltage adjustments. Each UTSi chip is mounted on different printed circuit boards (PCBs) which have holes with about 1 mm radius for optical output and input paths through the sapphire substrate. We discuss preliminary testing of these chips.

New geometric design consistency model based on operating speed profiles for road safety evaluation.

PubMed

Camacho-Torregrosa, Francisco J; Pérez-Zuriaga, Ana M; Campoy-Ungría, J Manuel; García-García, Alfredo

2013-12-01

To assist in the on-going effort to reduce road fatalities as much as possible, this paper presents a new methodology to evaluate road safety in both the design and redesign stages of two-lane rural highways. This methodology is based on the analysis of road geometric design consistency, a value which will be a surrogate measure of the safety level of the two-lane rural road segment. The consistency model presented in this paper is based on the consideration of continuous operating speed profiles. The models used for their construction were obtained by using an innovative GPS-data collection method that is based on continuous operating speed profiles recorded from individual drivers. This new methodology allowed the researchers to observe the actual behavior of drivers and to develop more accurate operating speed models than was previously possible with spot-speed data collection, thereby enabling a more accurate approximation to the real phenomenon and thus a better consistency measurement. Operating speed profiles were built for 33 Spanish two-lane rural road segments, and several consistency measurements based on the global and local operating speed were checked. The final consistency model takes into account not only the global dispersion of the operating speed, but also some indexes that consider both local speed decelerations and speeds over posted speeds as well. For the development of the consistency model, the crash frequency for each study site was considered, which allowed estimating the number of crashes on a road segment by means of the calculation of its geometric design consistency. Consequently, the presented consistency evaluation method is a promising innovative tool that can be used as a surrogate measure to estimate the safety of a road segment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Issues and Design Drivers for Deep Space Habitats

NASA Technical Reports Server (NTRS)

Rucker, Michelle A.; Anderson, Molly

2012-01-01

A cross-disciplinary team of scientists and engineers applied expertise gained in Lunar Lander development to the conceptual design of a long-duration, deep space habitat for Near Earth Asteroid (NEA) missions. The design reference mission involved two launches to assemble 5-modules for a 380-day round trip mission carrying 4 crew members. The conceptual design process yielded a number of interesting debates, some of which could be significant design drivers in a detailed Deep Space Habitat (DSH) design. These issues included: Design to minimize crew radiation exposure, launch loads, communications challenges, docking system and hatch commonality, pointing and visibility, consumables, and design for contingency operations.

Accident Prevention through Driving Skills Assessment and Interventions for Older Drivers: A Programmatic Research Project.

ERIC Educational Resources Information Center

Yee, Darlene; Melichar, Joseph F.

A study examined the effectiveness of a new computer-based multiphasic approach to identifying "at-risk" older drivers and remediating deficits in their driving and traffic safety attitudes, knowledge, and skills. Data collected from 250 older drivers in 3 states were used to develop specifications for computer-based driver improvement modules.…

Hatch latch mechanism for Spacelab scientific airlock

NASA Technical Reports Server (NTRS)

Terhaar, G. R.

1979-01-01

The requirements, design tradeoff, design, and performance of the Spacelab scientific airlock hatch latching mechanisms are described. At space side the hatch is closed and held against internal airlock/module pressure by 12 tangential overcenter hooks driven by a driver. At module side the hatch is held by 4 hooks driven by rollers running on a cammed driver.

User-controlled photographic animations, photograph-based questions, and questionnaires: three Internet-based instruments for measuring drivers' risk-taking behavior.

PubMed

Horswill, M S; Coster, M E

2001-02-01

The Internet has been exploited successfully in the past as a medium for behavioral research. This paper presents a series of studies designed to assess Internet-based measures of drivers' risk-taking behavior. First, we compared responses from an Internet sample with a traditional pencil-and-paper sample using established questionnaire measures of risk taking. No significant differences were found. Second, we assessed the validity of new Internet-based instruments, involving photographs and photographic animations, that measured speed, gap acceptance, and passing. Responses were found to reflect known demographic patterns of actual behavior to some degree. Also, a roadside survey of speeds was carried out at the locations depicted in the photographic measure of speeding and, with certain exceptions, differences between the two appeared to be constant. Third, a between-subject experimental manipulation involving the photographic animation measure of gap acceptance was used to demonstrate one application of these techniques.

Long-Term Benefits of Prompts to Use Safety Belts among Drivers Exiting Senior Communities

ERIC Educational Resources Information Center

Cox, Cory D.; Cox, Brian S.; Cox, Daniel J.

2005-01-01

Senior drivers are vulnerable to automobile crashes and subsequent injury and death. Safety belts reduce health risks associated with auto crashes. Therefore, it is important to encourage senior drivers to wear safety belts while driving. Using a repeated baseline design (AAB), we previously reported that motivating signs boosted safety belt usage…

Bicycles in Traffic. A North Carolina Driver Education Handbook.

ERIC Educational Resources Information Center

East Carolina Univ., Greenville, NC.

This unit is designed to provide driver educators with information for teaching automobile drivers about the traffic-mix problem between bicycles and motor vehicles on roadways. The purpose of the unit is to improve the safety of bicyclists on North Carolina highways and help to decrease the number of bicycle deaths and injuries caused by traffic…

Design optimization of space structures

NASA Technical Reports Server (NTRS)

Felippa, Carlos

1991-01-01

The topology-shape-size optimization of space structures is investigated through Kikuchi's homogenization method. The method starts from a 'design domain block,' which is a region of space into which the structure is to materialize. This domain is initially filled with a finite element mesh, typically regular. Force and displacement boundary conditions corresponding to applied loads and supports are applied at specific points in the domain. An optimal structure is to be 'carved out' of the design under two conditions: (1) a cost function is to be minimized, and (2) equality or inequality constraints are to be satisfied. The 'carving' process is accomplished by letting microstructure holes develop and grow in elements during the optimization process. These holes have a rectangular shape in two dimensions and a cubical shape in three dimensions, and may also rotate with respect to the reference axes. The properties of the perforated element are obtained through an homogenization procedure. Once a hole reaches the volume of the element, that element effectively disappears. The project has two phases. In the first phase the method was implemented as the combination of two computer programs: a finite element module, and an optimization driver. In the second part, focus is on the application of this technique to planetary structures. The finite element part of the method was programmed for the two-dimensional case using four-node quadrilateral elements to cover the design domain. An element homogenization technique different from that of Kikuchi and coworkers was implemented. The optimization driver is based on an augmented Lagrangian optimizer, with the volume constraint treated as a Courant penalty function. The optimizer has to be especially tuned to this type of optimization because the number of design variables can reach into the thousands. The driver is presently under development.

Survival pattern of first accident among commercial drivers in the Greater Accra Region of Ghana.

PubMed

Nanga, Salifu; Odai, Nii Afotey; Lotsi, Anani

2017-06-01

In this study, the average accident risk of commercial drivers in the Greater Accra region of Ghana and its associated risks were examined based on a survey data collected using paper-based questionnaires from 204 commercial drivers from the Greater Accra Region of Ghana. The Cox Proportional Hazards Model was used for multivariate analysis while the Kaplan-Meier (KM) Model was used to study the survival patterns of the commercial drivers. The study revealed that the median survival time for an accident to happen is 2.50 years. Good roads provided a better chance of survival than bad roads and experienced drivers have a better chance of survival than the inexperienced drivers. Age of driver, alcohol usage of driver, marital status, condition of road and duration of driver's license were found to be related to the risk of accident. Copyright © 2017 Elsevier Ltd. All rights reserved.

23 CFR 1327.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-04-01

... RECEIVING INFORMATION FROM THE NATIONAL DRIVER REGISTER PROBLEM DRIVER POINTER SYSTEM § 1327.3 Definitions... drivers who are, based on their records, suspected of being or known to be problem drivers. (d) Driver... personal identifying information in an inquiry compares with the personal identifying information on a...

Ergonomic evaluation of interior design of Shoka vehicle and proposing recommendations for improvement.

PubMed

Mazloumi, Adel; Mohammadreze, Fallah

2012-01-01

One of the applications of ergonomics disciplinary is designing driver workstation compatible to users' characteristics. The aim of this study was evaluation of interior design of Shoka vehicle with respect to the accommodation for Iranian population and proposing suggestions for customizing design of this vehicle. This study was a descriptive-analytical study conducted among thirty men from Iranian drivers population in 5, 50, 95 percentiles of the stature variable. Objective variables related to the occupant packaging and vehicle visual aspects including anthropometric variables, frontal, lateral, and side view and so on were investigated first. Then, subjective variables related to the driver mental workload and body comfort discomfort were studied using BMDMW and comfort questionnaires during 2-hour driving trial sessions. Occupant packaging variables and hand-arm angle showed the least accommodation percent (%53). Seating angles showed low accommodation as well (%73). Among three percentile groups there were no significant differences between the mean values of mental workload during two hours driving task. And, the mean value related to the comfort discomfort was 3.9 during driving sessions. Considering the findings in this study, it can be conclude that seating angles need correction and optimization. Taking mental workload results into account, it can be concluded that the interior design of the studied car had no influence on drivers' mental workload. From the aspect of comfort discomfort, Shoka vehicle showed neutral state among drivers. Optimizing seating angles, decreasing vibration, correcting stiffness of seating pan are suggested for customization of the ergonomics aspect of this vehicle.

A Fast Pulse, High Intensity Neutron Source Based Upon The Dense Plasma Focus

NASA Astrophysics Data System (ADS)

Krishnan, M.; Bures, B.; Madden, R.; Blobner, F.; Elliott, K. Wilson

2009-12-01

Alameda Applied Sciences Corporation (AASC) has built a bench-top source of fast neutrons (˜10-30 ns, 2.45 MeV), that is portable and can be scaled to operate at ˜100 Hz. The source is a Dense Plasma Focus driven by three different capacitor banks: a 40 J/30 kA/100 Hz driver; a 500 J/130 kA/2 Hz driver and a 3 kJ/350 kA/0.5 Hz driver. At currents of ˜130 kA, this source produces ˜1×107 (DD) n/pulse. The neutron pulse widths are ˜10-30 ns and may be controlled by adjusting the DPF electrode geometry and operating parameters. This paper describes the scaling of the fast neutron output with current from such a Dense Plasma Focus source. For each current and driver, different DPF head designs are required to match to the current rise-time, as the operating pressure and anode radius/shape are varied. Doping of the pure D2 gas fill with Ar or Kr was shown earlier to increase the neutron output. Results are discussed in the light of scaling laws suggested by prior literature.

Were they in the loop during automated driving? Links between visual attention and crash potential.

PubMed

Louw, Tyron; Madigan, Ruth; Carsten, Oliver; Merat, Natasha

2017-08-01

A proposed advantage of vehicle automation is that it relieves drivers from the moment-to-moment demands of driving, to engage in other, non-driving related, tasks. However, it is important to gain an understanding of drivers' capacity to resume manual control, should such a need arise. As automation removes vehicle control-based measures as a performance indicator, other metrics must be explored. This driving simulator study, conducted under the European Commission (EC) funded AdaptIVe project, assessed drivers' gaze fixations during partially-automated (SAE Level 2) driving, on approach to critical and non-critical events. Using a between-participant design, 75 drivers experienced automation with one of five out-of-the-loop (OOTL) manipulations, which used different levels of screen visibility and secondary tasks to induce varying levels of engagement with the driving task: 1) no manipulation, 2) manipulation by light fog, 3) manipulation by heavy fog, 4) manipulation by heavy fog plus a visual task, 5) no manipulation plus an n-back task. The OOTL manipulations influenced drivers' first point of gaze fixation after they were asked to attend to an evolving event. Differences resolved within one second and visual attention allocation adapted with repeated events, yet crash outcome was not different between OOTL manipulation groups. Drivers who crashed in the first critical event showed an erratic pattern of eye fixations towards the road centre on approach to the event, while those who did not demonstrated a more stable pattern. Automated driving systems should be able to direct drivers' attention to hazards no less than 6 seconds in advance of an adverse outcome. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Designing Inquiry for Upper Elementary Students: Lessons Learned from Driver's Ed

ERIC Educational Resources Information Center

Rabbat, Suzy

2014-01-01

One of the most memorable achievements of adolescence is the independence gained from obtaining a driver's license. Students are highly motivated to study the rules of the road, hone their skills behind the wheel, and meet all the state requirements to reach their goal. They are invested in the process because they value the outcome. The Driver's…

Safe Driving in Illinois. A Manual to Accompany the Illinois Rules of the Road.

ERIC Educational Resources Information Center

Rice, Gail; Nowack, Linda

Designed to accompany and supplement the Illinois Rules of the Road manual, this book is intended to better prepare future drivers for the written test for the instruction permit or driver's license. It includes many pictures and shows and describes driving situations a driver will probably face when behind the wheel. Parts dealing with important…

Driver's Enhanced Vision System (DEVS)

DOT National Transportation Integrated Search

1996-12-23

This advisory circular (AC) contains performance standards, specifications, and : recommendations for Drivers Enhanced Vision sSystem (DEVS). The FAA recommends : the use of the guidance in this publication for the design and installation of : DEVS e...

Driving Behavior among Different Groups of Iranian Drivers Based on Driver Coping Styles

PubMed Central

Lotfi, Saeid; Yazdanirad, Saeid; Pourabdiyan, Siyamak; Hassanzadeh, Akbar; Lotfi, Aliakbar

2017-01-01

Background: This study aimed to assess driving behavior of Iranian drivers based on their coping styles (problem-oriented, emotion-oriented, and avoiding). Methods: This study was conducted on 610 drivers divided into four different groups. The drivers’ behaviors and coping styles were evaluated using driver behavior questionnaire (DBQ) and coping inventory for stressful situations. Results: The results showed a significant difference among the three coping styles regarding the mean scores of DBQ dimensions (P < 0.001). In addition, the emotion-oriented drivers obtained higher mean scores compared to those with other coping styles. Conclusions: It can be concluded that emotion-oriented drivers were more susceptible to crashes compared to those with problem-solving and avoidance coping styles. PMID:28757929

Modifying behaviour to reduce over-speeding in work-related drivers: an objective approach.

PubMed

Newnam, Sharon; Lewis, Ioni; Warmerdam, Amanda

2014-03-01

The goal of this study was to utilise an objective measurement tool, via an on-board Diagnostic tool (OBDII), to explore the effectiveness of a behaviour modification intervention designed to reduce over-speed violations in a group of work-related drivers. It was predicted that over-speed violations would be decreased following participation in a behaviour modification intervention where drivers received weekly feedback on their speeding performance and goal setting exercises. The final analysis included the on-road behaviour of 16 drivers, all of whom completed each stage of the intervention programme. As predicted, over-speed violations significantly decreased from pre-test to post-test, after controlling for kilometres driven. These findings offer practical guidance for industry in developing interventions designed to improve work-related driving behaviour. Copyright © 2013 Elsevier Ltd. All rights reserved.

Re-occupancy of breeding territories by ferruginous hawks in Wyoming: Relationships to environmental and anthropogenic factors

Treesearch

Zachary P. Wallace; Patricia L. Kennedy; John R. Squires; Robert J. Oakleaf; Lucretia E. Olson; Katie M. Dugger

2016-01-01

Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by nonanthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models.We used design-based sampling and occupancy models to test relationships of...

A numerical tool for reproducing driver behaviour: experiments and predictive simulations.

PubMed

Casucci, M; Marchitto, M; Cacciabue, P C

2010-03-01

This paper presents the simulation tool called SDDRIVE (Simple Simulation of Driver performance), which is the numerical computerised implementation of the theoretical architecture describing Driver-Vehicle-Environment (DVE) interactions, contained in Cacciabue and Carsten [Cacciabue, P.C., Carsten, O. A simple model of driver behaviour to sustain design and safety assessment of automated systems in automotive environments, 2010]. Following a brief description of the basic algorithms that simulate the performance of drivers, the paper presents and discusses a set of experiments carried out in a Virtual Reality full scale simulator for validating the simulation. Then the predictive potentiality of the tool is shown by discussing two case studies of DVE interactions, performed in the presence of different driver attitudes in similar traffic conditions.

Using Self-Reliance Factors to Decide How to Share Control Between Human Powered Wheelchair Drivers and Ultrasonic Sensors.

PubMed

Sanders, David A

2017-08-01

A shared-control scheme for a powered wheelchair is presented. The wheelchair can be operated by a wheelchair driver using a joystick, or directed by a sensor system, or control can be combined between them. The wheelchair system can modify direction depending on the local environment. Sharing the control allows a disabled wheelchair driver to drive safely and efficiently. The controller automatically establishes the control gains for the sensor system and the human driver by calculating a self-reliance factor for the wheelchair driver. The sensor system can influence the motion of the wheelchair to compensate for some deficiency in a disabled driver. Practical tests validate the proposed techniques and designs.

The effects of sleep loss on young drivers' performance: A systematic review.

PubMed

Shekari Soleimanloo, Shamsi; White, Melanie J; Garcia-Hansen, Veronica; Smith, Simon S

2017-01-01

Young drivers (18-24 years) are over-represented in sleep-related crashes (comprising one in five fatal crashes in developed countries) primarily due to decreased sleep opportunity, lower tolerance for sleep loss, and ongoing maturation of brain areas associated with driving-related decision making. Impaired driving performance is the proximal reason for most car crashes. There is still a limited body of evidence examining the effects of sleep loss on young drivers' performance, with discrepancies in the methodologies used, and in the definition of outcomes. This study aimed to identify the direction and magnitude of the effects of sleep loss on young drivers' performance, and to appraise the quality of current evidence via a systematic review. Based on the Preferred Reporting Items for Systematic Reviews and Meta- Analyses (PRISMA) approach, 16 eligible studies were selected for review, and their findings summarised. Next, critical elements of these studies were identified, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines augmented to rate those elements. Using those criteria, the quality of individual papers was calculated and the overall body of evidence for each driving outcome were assigned a quality ranking (from 'very low' to 'high-quality'). Two metrics, the standard deviation of lateral position and number of line crossings, were commonly reported outcomes (although in an overall 'low-quality' body of evidence), with significant impairments after sleep loss identified in 50% of studies. While speed-related outcomes and crash events (also with very low- quality evidence) both increased under chronic sleep loss, discrepant findings were reported under conditions of acute total sleep deprivation. It is crucial to obtain more reliable data about the effects of sleep loss on young drivers' performance by using higher quality experimental designs, adopting common protocols, and the use of consistent metrics and reporting of findings based on GRADE criteria and the PRISMA statement. Key words: Young drivers, sleep loss, driving performance, PRISMA, the GRADE, systematic review.

Speed behaviour in work zone crossovers. A driving simulator study.

PubMed

Domenichini, Lorenzo; La Torre, Francesca; Branzi, Valentina; Nocentini, Alessandro

2017-01-01

Reductions in speed and, more critically, in speed variability between vehicles are considered an important factor to reduce crash risk in work zones. This study was designed to evaluate in a virtual environment the drivers' behaviour in response to nine different configurations of a motorway crossover work zone. Specifically, the speed behaviour through a typical crossover layout, designed in accordance with the Italian Ministerial Decree 10 July 2002, was compared with that of eight alternative configurations which differ in some characteristics such as the sequence of speed limits, the median opening width and the lane width. The influence of variable message signs, of channelizing devices and of perceptual treatments based on Human Factor principles were also tested. Forty-two participants drove in driving simulator scenarios while data on their speeds and decelerations were collected. The results indicated that drivers' speeds are always higher than the temporary posted speed limits for all configurations and that speeds decreases significantly only within the by-passes. However the implementation of higher speed limits, together with a wider median opening and taller channelization devices led to a greater homogeneity of the speeds adopted by the drivers. The presence of perceptual measures generally induced both the greatest homogenization of speeds and the largest reductions in mean speed values. Copyright © 2016 Elsevier Ltd. All rights reserved.

Experimental research on safety impacts of the inside shoulder based on driving simulation.

PubMed

Zhao, Xiaohua; Ding, Han; Wu, Yiping; Ma, Jianming; Zhong, Liande

2015-03-01

Statistical data shows that single-vehicle crashes account for half of all traffic crashes on expressways in China, and previous research has indicated that main contributing factors were related to whether and how the inside shoulder was paved. The inside shoulder provides space for drivers to make evasive maneuvers and accommodate driver errors. However, lower-cost construction solutions in China have resulted in the design of numerous urban expressway segments that lack inside shoulders. This paper has two objectives. The first is to reveal the safety impacts of inside shoulders on urban expressways by driving simulator experiment. The second objective is to propose optimal range and recommended value of inside shoulder width for designing inside shoulders of urban expressways. The empirical data, including subjects' eye movement data, heart rate (HR) and the lateral position of vehicles, were collected in a driving simulator. The data were analyzed to evaluate the safety impacts of the inside shoulder. The results have revealed that the inside shoulder has an impact on drivers' visual perception, behaviors, and psychology; in particular, it has a significant effect on vehicle operations. In addition, this paper recommends the desired and optimal inside shoulder widths for eight-lane, two-way divided expressways. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nuclear characteristics of a fissioning uranium plasma test reactor with light-water cooling

NASA Technical Reports Server (NTRS)

Whitmarsh, C. L., Jr.

1973-01-01

An analytical study was performed to determine a design configuration for a cavity test reactor. Test section criteria were that an average flux of 10 to the 15th power neutrons/sq cm/sec (E less than or equal to 0.12 eV) be supplied to a 61-cm-diameter spherical cavity at 200-atm pressure. Design objectives were to minimize required driver power, to use existing fuel-element technology, and to obtain fuel-element life of 10 to 100 full-power hours. Parameter calculations were made on moderator region size and material, driver fuel arrangement, control system, and structure in order to determine a feasible configuration. Although not optimized, a configuration was selected which would meet design criteria. The driver fuel region was a cylindrical annular region, one element thick, of 33 MTR-type H2O-cooled elements (Al-U fuel plate configuration), each 101 cm long. The region between the spherical test cavity and the cylindrical driver fuel region was Be (10 vol. % H2O coolant) with a midplane dimension of 8 cm. Exterior to the driver fuel, the 25-cm-thick cylindrical and axial reflectors were also Be with 10 vol. % H2O coolant. The entire reactor was contained in a 10-cm-thick steel pressure vessel, and the 200-atm cavity pressure was equalized throughout the driver reactor. Fuel-element life was 50 hr at the required driver power of 200 MW. Reactor control would be achieved with rotating poison drums located in the cylindrical reflector region. A control range of about 18 percent delta k/k was required for reactor operation.

High- and Low-Order Overtaking-Ability Affordances: Drivers Rely on the Maximum Velocity and Acceleration of Their Cars to Perform Overtaking Maneuvers.

PubMed

Basilio, Numa; Morice, Antoine H P; Marti, Geoffrey; Montagne, Gilles

2015-08-01

The aim of this study was to answer the question, Do drivers take into account the action boundaries of their car when overtaking? The Morice et al. affordance-based approach to visually guided overtaking suggests that the "overtake-ability" affordance can be formalized as the ratio of the "minimum satisfying velocity" (MSV) of the maneuver to the maximum velocity (V(max)) of the driven car. In this definition, however, the maximum acceleration (A(max)) of the vehicle is ignored. We hypothesize that drivers may be sensitive to an affordance redefined with the ratio of the "minimum satisfying acceleration" (MSA) to the A(max) of the car. Two groups of nine drivers drove cars differing in their A(max). They were instructed to attempt overtaking maneuvers in 25 situations resulting from the combination of five MSA and five MSV values. When overtaking frequency was expressed as a function of MSV and MSA, maneuvers were found to be initiated differently for the two groups. However, when expressed as a function of MSV/V(max) and MSA/A(max), overtaking frequency was quite similar for both groups. Finally, a multiple regression coefficient analysis demonstrated that overtaking decisions are fully explained by a composite variable comprising MSA/A(max) and the time required to reach MSV. Drivers reliably decide whether overtaking is safe (or not) by using low- and high-order variables taking into account their car's maximum velocity and acceleration, respectively, as predicted by "affordance-based control" theory. Potential applications include the design of overtaking assistance, which should exploit the MSA/A(max) variables in order to suggest perceptually relevant overtaking solutions. © 2015, Human Factors and Ergonomics Society.

What the drivers do and do not tell you: using verbal protocol analysis to investigate driver behaviour in emergency situations.

PubMed

Banks, Victoria A; Stanton, Neville A; Harvey, Catherine

2014-01-01

Although task analysis of pedestrian detection can provide us with useful insights into how a driver may behave in emergency situations, the cognitive elements of driver decision-making are less well understood. To assist in the design of future Advanced Driver Assistance Systems, such as Autonomous Emergency Brake systems, it is essential that the cognitive elements of the driving task are better understood. This paper uses verbal protocol analysis in an exploratory fashion to uncover the thought processes underlying behavioural outcomes represented by hard data collected using the Southampton University Driving Simulator.

Simple, low-noise piezo driver with feed-forward for broad tuning of external cavity diode lasers.

PubMed

Doret, S Charles

2018-02-01

We present an inexpensive, low-noise (<260 μV rms , 0.1 Hz-100 kHz) design for a piezo driver suitable for frequency tuning of external-cavity diode lasers. This simple driver improves upon many commercially available drivers by incorporating circuitry to produce a "feed-forward" signal appropriate for making simultaneous adjustments to the piezo voltage and laser current, enabling dramatic improvements in a mode-hop-free laser frequency tuning range. We present the theory behind our driver's operation, characterize its output noise, and demonstrate its use in absorption spectroscopy on the rubidium D 1 line.

Using the centre of percussion to design a steering controller for an autonomous race car

NASA Astrophysics Data System (ADS)

Kritayakirana, Krisada; Gerdes, J. Christian

2012-01-01

Understanding how a race car driver controls a vehicle at its friction limits can provide insights into the development of vehicle safety systems. In this paper, a race car driver's behaviour inspires the design of an autonomous racing controller. The resulting controller uses the vehicle's centre of percussion (COP) to design feedforward and feedback steering. At the COP, the effects of rotation and translation from the rear tire force cancel each other out; consequently, the feedforward steering command is robust to the disturbances from the rear tire force. Using the COP also simplifies the equations of motion, as the vehicle's lateral motion is decoupled from the vehicle's yaw motion and highlights the challenge of controlling a vehicle when the rear tires are highly saturated. The resulting dynamics can be controlled with a linear state feedback based on a lane-keeping system with additional yaw damping. Utilising Lyapunov theory, the closed-loop system is shown to remain stable even when the rear tires are highly saturated. The experimental results demonstrate that an autonomous vehicle can operate at its limits while maintaining a minimal lateral error.

Osiris and SOMBRERO inertial confinement fusion power plant designs. Volume 2, Designs, assessments, and comparisons, Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meier, W.R.; Bieri, R.L.; Monsler, M.J.

1992-03-01

The primary objective of the of the IFE Reactor Design Studies was to provide the Office of Fusion Energy with an evaluation of the potential of inertial fusion for electric power production. The term reactor studies is somewhat of a misnomer since these studies included the conceptual design and analysis of all aspects of the IFE power plants: the chambers, heat transport and power conversion systems, other balance of plant facilities, target systems (including the target production, injection, and tracking systems), and the two drivers. The scope of the IFE Reactor Design Studies was quite ambitious. The majority of ourmore » effort was spent on the conceptual design of two IFE electric power plants, one using an induction linac heavy ion beam (HIB) driver and the other using a Krypton Fluoride (KrF) laser driver. After the two point designs were developed, they were assessed in terms of their (1) environmental and safety aspects; (2) reliability, availability, and maintainability; (3) technical issues and technology development requirements; and (4) economics. Finally, we compared the design features and the results of the assessments for the two designs.« less

Using naturalistic driving films as a design tool for investigating driver requirements in HMI design for ADAS.

PubMed

Wang, Minjuan; Sun, Dong; Chen, Fang

2012-01-01

In recent years, there are many naturalistic driving projects have been conducted, such as the 100-Car Project (Naturalistic Driving study in United State), EuroFOT(European Large-Scale Field Operational Tests on Vehicle Systems), SeMi- FOT(Sweden Michigan Naturalistic Field Operational Test and etc. However, those valuable naturalistic driving data hasn't been applied into Human-machine Interaction (HMI) design for Advanced Driver Assistance Systems (ADAS), a good HMI design for ADAS requires a deep understanding of drive environment and the interactions between the driving car and other road users in different situations. The results demonstrated the benefits of using naturalistic driving films as a mean for enhancing focus group discussion for better understanding driver's needs and traffic environment constraints. It provided an efficient tool for designers to have inside knowledge about drive and the needs for information presentation; The recommendations for how to apply this method is discussed in the paper.

Young drivers' optimism bias for accident risk and driving skill: Accountability and insight experience manipulations.

PubMed

White, Melanie J; Cunningham, Lauren C; Titchener, Kirsteen

2011-07-01

This study aimed to determine whether two brief, low cost interventions would reduce young drivers' optimism bias for their driving skills and accident risk perceptions. This tendency for such drivers to perceive themselves as more skillful and less prone to driving accidents than their peers may lead to less engagement in precautionary driving behaviours and a greater engagement in more dangerous driving behaviour. 243 young drivers (aged 17-25 years) were randomly allocated to one of three groups: accountability, insight or control. All participants provided both overall and specific situation ratings of their driving skills and accident risk relative to a typical young driver. Prior to completing the questionnaire, those in the accountability condition were first advised that their driving skills and accident risk would be later assessed via a driving simulator. Those in the insight condition first underwent a difficult computer-based hazard perception task designed to provide participants with insight into their potential limitations when responding to hazards in difficult and unpredictable driving situations. Participants in the control condition completed only the questionnaire. Results showed that the accountability manipulation was effective in reducing optimism bias in terms of participants' comparative ratings of their accident risk in specific situations, though only for less experienced drivers. In contrast, among more experienced males, participants in the insight condition showed greater optimism bias for overall accident risk than their counterparts in the accountability or control groups. There were no effects of the manipulations on drivers' skills ratings. The differential effects of the two types of manipulations on optimism bias relating to one's accident risk in different subgroups of the young driver sample highlight the importance of targeting interventions for different levels of experience. Accountability interventions may be beneficial for less experienced young drivers but the results suggest exercising caution with the use of insight type interventions, particularly hazard perception style tasks, for more experienced young drivers typically still in the provisional stage of graduated licensing systems. Copyright © 2011 Elsevier Ltd. All rights reserved.

Central Heat and Power Plant Coal Dust and Silica Risk Management, Eielson Air Force Base, Alaska

DTIC Science & Technology

2014-12-11

the dump truck driver, lowers the telescopic chute into a hole at the top of the ash box on the dump truck and then activates the screw conveyor ...addition to the main ammonia health risk assessment letter and designed to inform EAFB of the status of the pending silica rule, exposure assessment...main ammonia health risk assessment letter, AFRL- SA-WP-CL-2014-0014, and designed to inform EAFB of the status of the pending silica rule, exposure

Population distributions of time to collision at brake application during car following from naturalistic driving data.

PubMed

Kusano, Kristofer D; Chen, Rong; Montgomery, Jade; Gabler, Hampton C

2015-09-01

Forward collision warning (FCW) systems are designed to mitigate the effects of rear-end collisions. Driver acceptance of these systems is crucial to their success, as perceived "nuisance" alarms may cause drivers to disable the systems. In order to make customizable FCW thresholds, system designers need to quantify the variation in braking behavior in the driving population. The objective of this study was to quantify the time to collision (TTC) that drivers applied the brakes during car following scenarios from a large scale naturalistic driving study (NDS). Because of the large amount of data generated by NDS, an automated algorithm was developed to identify lead vehicles using radar data recorded as part of the study. Using the search algorithm, all trips from 64 drivers from the 100-Car NDS were analyzed. A comparison of the algorithm to 7135 brake applications where the presence of a lead vehicle was manually identified found that the algorithm agreed with the human review 90.6% of the time. This study examined 72,123 trips that resulted in 2.6 million brake applications. Population distributions of the minimum, 1st, and 10th percentiles were computed for each driver in speed ranges between 3 and 60 mph in 10 mph increments. As speed increased, so did the minimum TTC experience by drivers as well as variance in TTC. Younger drivers (18-30) had lower TTC at brake application compared to older drivers (30-51+), especially at speeds between 40 mph and 60 mph. This is one of the first studies to use large scale NDS data to quantify braking behavior during car following. The results of this study can be used to design and evaluate FCW systems and calibrate traffic simulation models. Copyright © 2015 Elsevier Ltd and National Safety Council. All rights reserved.

The Effect of Differences in Day and Night Lighting Distributions on Drivers' Speed Perception.

PubMed

Kim, Jonathan D; Perrone, John A; Isler, Robert B

2017-06-01

Previous research has shown that changes to contrast levels in the visual environment caused by fog can affect drivers' perceptions of speed. It is not easy, however, to extrapolate these results to other driving scenarios in which contrast is affected, such as during nighttime driving, because the measure of contrast is more complex when considering factors such as the illumination provided by headlights. Therefore, we investigated the differences in lighting distribution patterns between day- and nighttime driving on speed perception using prerendered 3D scenarios representing driving on a rural road. A two-alternative forced-choice design based on the method of constant stimuli was utilised, with 32 participants viewing a series of pairs of scenarios (day vs. night driving) from a driver's perspective while indicating for each pair whether the second scenario was faster or slower than the first scenario. Our results indicated that speed discrimination accuracy was minimally affected by changes in lighting distribution patterns between day and night.

Policy prescriptions to preserve mobility for seniors--A dose of realism.

PubMed

Staplin, Loren; Freund, Katherine

2013-12-01

This paper advocates policy change in three key areas: infrastructure, driver licensing, and access to private resources for transportation alternatives. Policy makers are encouraged to plan for the transportation future of our aging society by prioritizing public expenditures for roads and highways according to design and engineering practices already proven to assist older drivers and pedestrians. By adopting minimum, evidence-based requirements for visual, mental and physical capability for licensure and uniformly applying them at all ages, across all states, policy makers can improve the safety of older drivers without unfairly restricting their mobility-and need not increase the regulatory burden in doing so. By reviewing and replicating already successful state policies that either create incentives or remove barriers to the use of private resources for non-profit, senior transportation, policy makers can help communities access the labor and capital, as well as manage the risks of market-oriented, non-profit mobility solutions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Decentralised systems - definition and drivers in the current context.

PubMed

Sharma, Ashok K; Tjandraatmadja, Grace; Cook, Stephen; Gardner, Ted

2013-01-01

This paper explores the current context for decentralised approaches in the provision of urban water services. It examines the recent history of decentralised systems' implementation in Australia and identifies its drivers. The drivers included addressing capacity constraints of centralised systems, mitigating the environmental impact of urban development, and increasing the resilience of urban water systems to episodic droughts and the projected impacts of climate change. The concepts of integrated urban water management and water sensitive urban design were prevalent in many of the innovative approaches used for the provision of decentralised urban water services. However, there remains a degree of confusion among water professionals in the terminology adopted for on-site and decentralised systems. Based on a literature review, consultation with water industry professionals and examination of decentralised urban developments in Australia, this paper has developed a generalised definition of decentralised systems for adoption across the water sector. The definition encompasses the various development scales in which decentralised systems are implemented, and reflects the new functions and characteristics inherent to those systems.

Intelligent behaviors through vehicle-to-vehicle and vehicle-to-infrastructure communication

NASA Astrophysics Data System (ADS)

Garcia, Richard D.; Sturgeon, Purser; Brown, Mike

2012-06-01

The last decade has seen a significant increase in intelligent safety devices on private automobiles. These devices have both increased and augmented the situational awareness of the driver and in some cases provided automated vehicle responses. To date almost all intelligent safety devices have relied on data directly perceived by the vehicle. This constraint has a direct impact on the types of solutions available to the vehicle. In an effort to improve the safety options available to a vehicle, numerous research laboratories and government agencies are investing time and resources into connecting vehicles to each other and to infrastructure-based devices. This work details several efforts in both the commercial vehicle and the private auto industries to increase vehicle safety and driver situational awareness through vehicle-to-vehicle and vehicle-to-infrastructure communication. It will specifically discuss intelligent behaviors being designed to automatically disable non-compliant vehicles, warn tractor trailer vehicles of unsafe lane maneuvers such as lane changes, passing, and merging, and alert drivers to non-line-of-sight emergencies.

An examination of the relationship between measures of impulsivity and risky simulated driving amongst young drivers.

PubMed

Hatfield, Julie; Williamson, Ann; Kehoe, E James; Prabhakharan, Prasannah

2017-06-01

The risky driving of young drivers may owe in part to youthful motivations (such as experience-seeking, authority rebellion, desire for peer approval) combined with incompletely developed impulse control. Although self-reported impulsiveness has been positively associated with self-reports of risky driving, results based on objective measures of response inhibition (e.g., Go/No-go tasks) have been inconclusive. The present study examined interrelationships between measures of response inhibition, self-report impulsiveness scales, and responses to events during a simulated drive that were designed to detect impulsive, unsafe behaviours (e.g., turning across on-coming traffic). Participants were 72 first-year Psychology students. More speeding and "Unsafe" responding to critical events during simulated driving were associated with poorer impulse control as assessed by commission errors during a Go/No-Go task. These results consolidate evidence for a relationship between impulse control and risky driving amongst young drivers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Holography: Use in Training and Testing Drivers on the Road in Accident Avoidance.

ERIC Educational Resources Information Center

Frey, Allan H.; Frey, Donnalyn

1979-01-01

Defines holography, identifies visual factors in driving and the techniques used in on-road visual presentations, and presents the design and testing of a holographic system for driver training. (RAO)

Prevalence of driver physical factors leading to unintentional lane departure crashes.

PubMed

Cicchino, Jessica B; Zuby, David S

2017-07-04

Some lane-keeping assist systems in development and production provide autonomous braking and steering to correct unintentional lane drift but otherwise require drivers to fully control their vehicles. The goal of this study was to quantify the proportion of drivers involved in unintentional lane drift crashes who would be unable to regain control of their vehicles to inform the design of such systems. The NHTSA's National Motor Vehicle Crash Causation Survey collected in-depth, on-scene data for a nationally representative sample of 5,470 U.S. police-reported passenger vehicle crashes during 2005-2007 that occurred between 6 a.m. and midnight and for which emergency medical services were dispatched. The physical states of drivers involved in the 631 lane drift crashes in the sample, which represented 259,034 crashes nationally, were characterized. Thirty-four percent of drivers who crashed because they drifted from their lanes were sleeping or otherwise incapacitated. These drivers would be unlikely to regain full control of their vehicles if an active safety system prevented their initial drift. An additional 13% of these drivers had a nonincapacitating medical issue, blood alcohol concentration (BAC) ≥ 0.08%, or other physical factor that may not allow them to regain full vehicle control. When crashes involved serious or fatal injuries, 42% of drivers who drifted were sleeping or otherwise incapacitated, and an additional 14% were impacted by a nonincapacitating medical issue, BAC ≥ 0.08%, or other physical factor. Designers of active safety systems that provide autonomous lateral control should consider that a substantial proportion of drivers at risk of lane drift crashes are incapacitated. Systems that provide only transient corrective action may not ultimately prevent lane departure crashes for these drivers, and drivers who do avoid lane drift crashes because of these systems may be at high risk of other types of crashes when they attempt to regain control. Active lane-keeping assist systems may need to be combined with in-vehicle driver monitoring to identify incapacitated drivers and safely remove them from the roadway if the systems are to reach their maximum potential benefit.

An Australasian model license reassessment procedure for identifying potentially unsafe drivers.

PubMed

Fildes, Brian N; Charlton, Judith; Pronk, Nicola; Langford, Jim; Oxley, Jennie; Koppel, Sjaanie

2008-08-01

Most licensing jurisdictions in Australia currently employ age-based assessment programs as a means to manage older driver safety, yet available evidence suggests that these programs have no safety benefits. This paper describes a community referral-based model license re assessment procedure for identifying and assessing potentially unsafe drivers. While the model was primarily developed for assessing older driver fitness to drive, it could be applicable to other forms of driver impairment associated with increased crash risk. It includes a three-tier process of assessment, involving the use of validated and relevant assessment instruments. A case is argued that this process is a more systematic, transparent and effective process for managing older driver safety and thus more likely to be widely acceptable to the target community and licensing authorities than age-based practices.

Shuttle's 160 hour ground turnaround - A design driver

NASA Technical Reports Server (NTRS)

Widick, F.

1977-01-01

Turnaround analysis added a new dimension to the Space Program with the advent of the Space Shuttle. The requirement to turn the flight hardware around in 160 working hours from landing to launch was a significant design driver and a useful tool in forcing the integration of flight and ground systems design to permit an efficient ground operation. Although there was concern that time constraints might increase program costs, the result of the analysis was to minimize facility requirements and simplify operations with resultant cost savings.

Dominant role of drivers' attitude in prevention of road traffic crashes: a study on knowledge, attitude, and practice of drivers in Iran.

PubMed

Mirzaei, Ramazan; Hafezi-Nejad, Nima; Sadegh Sabagh, Mohammad; Ansari Moghaddam, Alireza; Eslami, Vahid; Rakhshani, Fatemeh; Rahimi-Movaghar, Vafa

2014-05-01

Evaluating the relation between Iranian drivers' knowledge, attitude, and practice (KAP) regarding traffic regulations, and their deterministic effect on road traffic crashes (RTCs). Two cities of Tehran and Zahedan, Iran. A cross-sectional study was designed. Using a simplified cluster sampling design, 2200 motor vehicle drivers including 1200 in Tehran and 1000 in Zahedan were selected. Sixty locations in Tehran and 50 in Zahedan were chosen. In each pre-identified location, 20 adult drivers were approached consecutively. A questionnaire developed by researchers was filled by each participant. The questionnaire had four sections including items assessing the demographics, knowledge, attitude and practice of drivers toward traffic regulations. Logistic regression analysis was used to evaluate the relationship between the RTCs and KAP variables. The study sample consisted of 619 (28.1%) occupational and 1580 (71.8%) private drivers. Among them, 86.4% were male. The median age was 33.6 ± 10.83. Drivers in Tehran and Zahedan had no significant differences between their mean scores of KAP items of the questionnaire. Higher knowledge, safer attitude, and safer practice were associated with a decreased number of RTC. After adjusting for possible confounders, increase of one standard deviation in attitude and practice scores (but not knowledge) resulted in 26.4% and 18.5% decrease in RTC, respectively. Finally, considering knowledge, attitude and practice of drivers in one model to assess their mutual effect, it was shown that only attitude is significantly associated with a decrease of RTC (OR=0.76, P=0.007). Increase in attitude and practice accompanied with decreased number of RTCs in Iranian drivers. Specifically, drivers' attitude had the crucial effect. It is not knowledge and standard traffic education; rather it is how such education is registered as an attitude that translates what is being learned into actions. Without safer attitude, even safer self-reported practice will not result in lower RTCs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Developing and evaluating a mobile driver fatigue detection network based on electroencephalograph signals

PubMed Central

Yin, Jinghai; Mu, Zhendong

2016-01-01

The rapid development of driver fatigue detection technology indicates important significance of traffic safety. The authors’ main goals of this Letter are principally three: (i) A middleware architecture, defined as process unit (PU), which can communicate with personal electroencephalography (EEG) node (PEN) and cloud server (CS). The PU receives EEG signals from PEN, recognises the fatigue state of the driver, and transfer this information to CS. The CS sends notification messages to the surrounding vehicles. (ii) An android application for fatigue detection is built. The application can be used for the driver to detect the state of his/her fatigue based on EEG signals, and warn neighbourhood vehicles. (iii) The detection algorithm for driver fatigue is applied based on fuzzy entropy. The idea of 10-fold cross-validation and support vector machine are used for classified calculation. Experimental results show that the average accurate rate of detecting driver fatigue is about 95%, which implying that the algorithm is validity in detecting state of driver fatigue. PMID:28529761

Developing and evaluating a mobile driver fatigue detection network based on electroencephalograph signals.

PubMed

Yin, Jinghai; Hu, Jianfeng; Mu, Zhendong

2017-02-01

The rapid development of driver fatigue detection technology indicates important significance of traffic safety. The authors' main goals of this Letter are principally three: (i) A middleware architecture, defined as process unit (PU), which can communicate with personal electroencephalography (EEG) node (PEN) and cloud server (CS). The PU receives EEG signals from PEN, recognises the fatigue state of the driver, and transfer this information to CS. The CS sends notification messages to the surrounding vehicles. (ii) An android application for fatigue detection is built. The application can be used for the driver to detect the state of his/her fatigue based on EEG signals, and warn neighbourhood vehicles. (iii) The detection algorithm for driver fatigue is applied based on fuzzy entropy. The idea of 10-fold cross-validation and support vector machine are used for classified calculation. Experimental results show that the average accurate rate of detecting driver fatigue is about 95%, which implying that the algorithm is validity in detecting state of driver fatigue.

A VxD-based automatic blending system using multithreaded programming.

PubMed

Wang, L; Jiang, X; Chen, Y; Tan, K C

2004-01-01

This paper discusses the object-oriented software design for an automatic blending system. By combining the advantages of a programmable logic controller (PLC) and an industrial control PC (ICPC), an automatic blending control system is developed for a chemical plant. The system structure and multithread-based communication approach are first presented in this paper. The overall software design issues, such as system requirements and functionalities, are then discussed in detail. Furthermore, by replacing the conventional dynamic link library (DLL) with virtual X device drivers (VxD's), a practical and cost-effective solution is provided to improve the robustness of the Windows platform-based automatic blending system in small- and medium-sized plants.

The anti-fatigue driving system design based on the eye blink detect

NASA Astrophysics Data System (ADS)

Yang, Shuyu; Song, Xin; Zhang, Li; Yu, Jie

2017-01-01

Traffic accident is one of the severe social problems in the world, but the appraisal and prevention of the fatigue driving is still a difficult problem that can not be solved. This paper is to study the results of fatigue driving and the existing antifatigue driving products, collecting brain wave with the TGAM (ThinkGear AM) Brain Wave Sensor Chip. We analyze the collected waveform based on eye blink detect algorithm to work out current situation of the driver. According to the analysis results, Sound Module and controllable speed car will make a series of feedback. Finally, an effective Anti- Fatigue Driving System is designed based on all above.

Diode-pumped solid state lasers (DPSSLs) for Inertial Fusion Energy (IFE)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krupke, W.F.

The status of diode-pumped, transverse-gas-flow cooled, Yb-S-FAP slab lasers is reviewed. Recently acquired experimental performance data are combined with a cost/performance IFE driver design code to define a cost-effective development path for IFE DPSSL drivers. Specific design parameters are described for the Mercury 100J/10 Hz, 1 kW system (first in the development scenario).

Classifying visuomotor workload in a driving simulator using subject specific spatial brain patterns

PubMed Central

Dijksterhuis, Chris; de Waard, Dick; Brookhuis, Karel A.; Mulder, Ben L. J. M.; de Jong, Ritske

2013-01-01

A passive Brain Computer Interface (BCI) is a system that responds to the spontaneously produced brain activity of its user and could be used to develop interactive task support. A human-machine system that could benefit from brain-based task support is the driver-car interaction system. To investigate the feasibility of such a system to detect changes in visuomotor workload, 34 drivers were exposed to several levels of driving demand in a driving simulator. Driving demand was manipulated by varying driving speed and by asking the drivers to comply to individually set lane keeping performance targets. Differences in the individual driver's workload levels were classified by applying the Common Spatial Pattern (CSP) and Fisher's linear discriminant analysis to frequency filtered electroencephalogram (EEG) data during an off line classification study. Several frequency ranges, EEG cap configurations, and condition pairs were explored. It was found that classifications were most accurate when based on high frequencies, larger electrode sets, and the frontal electrodes. Depending on these factors, classification accuracies across participants reached about 95% on average. The association between high accuracies and high frequencies suggests that part of the underlying information did not originate directly from neuronal activity. Nonetheless, average classification accuracies up to 75–80% were obtained from the lower EEG ranges that are likely to reflect neuronal activity. For a system designer, this implies that a passive BCI system may use several frequency ranges for workload classifications. PMID:23970851

Evaluating the Effects of Traffic on Driver Stopping and Turn Signal Use at a Stop Sign: A Systematic Replication

ERIC Educational Resources Information Center

Lebbon, Angela R.; Austin, John; Van Houten, Ron; Malenfant, Louis E.

2007-01-01

The current analyses of observational data found that oncoming traffic substantially affected driver stopping patterns and turn signal use at the target stop sign. The percentage of legal stops and turn signal use by drivers in the presence and absence of traffic was analyzed using a multi-element design. The results showed that legal stops were…

A contribution to the availability of lunar resources for powered construction

NASA Technical Reports Server (NTRS)

Heppenheimer, T. A.

1980-01-01

The use of lunar resources to construct solar power satellites wherein the resources are transported by a lunar mass driver is discussed. The minimization of cross track errors in the launch of payloads by mass driver is emphasized. The design and construction of the mass driver is outlined. Features of the proposed system addressed include passive magnetic damping, separation and snapout, and downrange correction.

Backing collisions: a study of drivers’ eye and backing behaviour using combined rear-view camera and sensor systems

PubMed Central

Hurwitz, David S; Pradhan, Anuj; Fisher, Donald L; Knodler, Michael A; Muttart, Jeffrey W; Menon, Rajiv; Meissner, Uwe

2012-01-01

Context Backing crash injures can be severe; approximately 200 of the 2,500 reported injuries of this type per year to children under the age of 15 years result in death. Technology for assisting drivers when backing has limited success in preventing backing crashes. Objectives Two questions are addressed: Why is the reduction in backing crashes moderate when rear-view cameras are deployed? Could rear-view cameras augment sensor systems? Design 46 drivers (36 experimental, 10 control) completed 16 parking trials over 2 days (eight trials per day). Experimental participants were provided with a sensor camera system, controls were not. Three crash scenarios were introduced. Setting Parking facility at UMass Amherst, USA. Subjects 46 drivers (33 men, 13 women) average age 29 years, who were Massachusetts residents licensed within the USA for an average of 9.3 years. Interventions Vehicles equipped with a rear-view camera and sensor system-based parking aid. Main Outcome Measures Subject’s eye fixations while driving and researcher’s observation of collision with objects during backing. Results Only 20% of drivers looked at the rear-view camera before backing, and 88% of those did not crash. Of those who did not look at the rear-view camera before backing, 46% looked after the sensor warned the driver. Conclusions This study indicates that drivers not only attend to an audible warning, but will look at a rear-view camera if available. Evidence suggests that when used appropriately, rear-view cameras can mitigate the occurrence of backing crashes, particularly when paired with an appropriate sensor system. PMID:20363812

Older adult opinions of "advance driving directives".

PubMed

Betz, Marian E; Lowenstein, Steven R; Schwartz, Robert

2013-01-01

Discussions about driving cessation are difficult. "Advance driving directives" (ADDs), like advance directives for end-of-life care, would allow drivers to designate someone to help make driving decisions for them in the future. It is not known if older drivers support the concept of ADDs. Cross-sectional study of a convenience sample of English-speaking drivers (55+ years) at 2 independent living facilities and 2 community centers who completed anonymous surveys. Of 168 participants, 80% were female; the median age was 76.5 years (range = 56-93 years). Most (74%) drove daily or almost daily, and 7% reported a crash in the past year. Few had spoken with someone about driving safety (5%) or their wishes when driving skills decline (21%). Of the few who had discussed this topic, 83% had spoken with a family member; only 17% had spoken with a health care provider. However, participants were open to driving discussions, and 54% said they would be willing to complete an ADD if recommended. Of these, 79% said it was "likely" or "very likely" they would comply with the directive in the future. Most (73%) supported mandatory, age-based retesting; the median recommended testing age suggested was 80 years. More participants thought the driver (71%), a family member (61%), or a physician (59%) should determine license revocation for an unsafe driver, rather than the department of motor vehicles (32%). Many older drivers may be open to discussing their driving plans with physicians and family members. ADDs may facilitate these discussions in the present and help define driving-related wishes in the future.

Evaluating the Impact of Whole-Body Vibration (WBV) on Fatigue and the Implications for Driver Safety.

PubMed

Troxel, Wendy M; Helmus, Todd C; Tsang, Flavia; Price, Carter C

2016-05-09

Driver fatigue is a significant contributor to motor vehicle accidents and fatalities, although the exact share of those events attributable to fatigue is still uncertain. In 2013, accidents involving heavy trucks killed more than 3,944 people in the United States, with over 80 percent of those killed not in the truck. Numerous factors contribute to driver fatigue among commercial drivers, including shiftwork schedules; high prevalence of alcohol and substance use; extended hours; comorbid medical conditions, such as pain; and high prevalence of sleep disorders. Many of these factors have been studied extensively in the trucking industry. Whole-body vibration (WBV) is another potential factor that may contribute to driver fatigue, but it has received little attention. Beginning in January 2015, Bose Corporation and AIG commissioned the RAND Corporation to study the link between WBV and driver fatigue. This article summarizes the findings from RAND's systematic review of the literature on WBV and fatigue as well as considers appropriate study designs and methodology that will inform new areas of research focused on improving the safety of truckers and those who share the road with them. The literature review identified 24 studies examining the impact of WBV on fatigue or sleepiness. The majority of studies (n = 18) found a significant association between WBV and fatigue or sleepiness; however, there are several limitations of the existing literature that preclude definitive conclusions regarding the impact of WBV on these outcomes. This research concludes with recommendations for future studies to strengthen the evidence base.

Color adjustable LED driver design based on PWM

NASA Astrophysics Data System (ADS)

Du, Yiying; Yu, Caideng; Que, Longcheng; Zhou, Yun; Lv, Jian

2012-10-01

Light-emitting diode (LED) is a liquid cold source light source that rapidly develops in recent years. The merits of high brightness efficiency, long duration, high credibility and no pollution make it satisfy our demands for consumption and natural life, and gradually replace the traditional lamp-house-incandescent light and fluorescent light. However, because of the high cost and unstable drive circuit, the application range is restricted. To popularize the applications of the LED, we focus on improving the LED driver circuit to change this phenomenon. Basing on the traditional LED drive circuit, we adopt pre-setup constant current model and introduce pulse width modulation (PWM) control method to realize adjustable 256 level-grays display. In this paper, basing on human visual characteristics and the traditional PWM control method, we propose a new PWM control timing clock to alter the duty cycle of PWM signal to realize the simple gamma correction. Consequently, the brightness can accord with our visual characteristics.

A multiyear assessment of a hospital-school program to promote teen motor vehicle safety.

PubMed

Unni, Purnima; Estrada, Cristina M; Chung, Dai H; Riley, Emily B; Worsley-Hynd, Lesley; Stinson, Neil

2017-08-01

Motor vehicle crashes are the leading cause of death among teen drivers. The main goal of this program was to reduce texting while driving among high school teens through a unique peer-generated anti-texting campaign. The program consisted of two phases. In phase 1, student leaders participated in a half-day, hospital-based experiential program that emphasized safe teen driving. In phase 2, these students conceptualized and implemented an anti-texting while driving campaign during the school year. The program enrolled 32 schools with 137 student participants in phase 1.This study uses a prospective quasi-experimental pre-post design. A presurvey and a follow-up online survey were used. Response rate was 81%. In phase 2, two rounds of observations of drivers were made near the participating schools at the beginning and end of the phase 2 campaign. The results were analyzed using proportion tests. There was a strong belief (6.49 on a seven-point scale) that texting while driving could result in a crash. About 58% had texted while driving in the previous 7 days in the pre-survey. This proportion decreased significantly to 44% in the follow-up (p < 0.05). Knowledge of Tennessee Graduated Driver Licensing laws and feeling of empowerment to take action with a teen driver who was texting improved significantly (p < 0.05). In phase 2, 12,309 drivers (adults and teens) were observed in the first round, and 13,153 were observed in the second round of observations. Significant reduction in the proportion of drivers texting while driving (from 13% to 9%; p < 0.0001) was observed. Results of driver observations support the effectiveness of this program in meeting the key objective of reducing texting while driving. The program also influenced teenagers' willingness to take positive steps when faced with a driver who was texting. Future efforts should aim to influence social and peer norms. Therapeutic study, level III.

A multiyear assessment of a hospital-school program to promote teen motor vehicle safety.

PubMed

Unni, Purnima; Estrada, Cristina M; Chung, Dai H; Riley, Emily B; Worsley-Hynd, Lesley; Stinson, Neil

2017-11-01

Motor vehicle crashes are the leading cause of death among teen drivers. The main goal of this program was to reduce texting while driving among high school teens through a unique peer-generated anti-texting campaign. The program consisted of two phases. In phase 1, student leaders participated in a half-day, hospital-based experiential program that emphasized safe teen driving. In phase 2, these students conceptualized and implemented an anti-texting while driving campaign during the school year. The program enrolled 32 schools with 137 student participants in phase 1. This study uses a prospective quasi-experimental pre-post design. A presurvey and a follow-up online survey were used. Response rate was 81%. In phase 2, two rounds of observations of drivers were made near the participating schools at the beginning and end of the phase 2 campaign. The results were analyzed using proportion tests. There was a strong belief (6.49 on a seven-point scale) that texting while driving could result in a crash. About 58% had texted while driving in the previous 7 days in the pre-survey. This proportion decreased significantly to 44% in the follow-up (p < 0.05). Knowledge of Tennessee Graduated Driver Licensing laws and feeling of empowerment to take action with a teen driver who was texting improved significantly (p < 0.05). In phase 2, 12,309 drivers (adults and teens) were observed in the first round, and 13,153 were observed in the second round of observations. Significant reduction in the proportion of drivers texting while driving (from 13% to 9%; p < 0.0001) was observed. Results of driver observations support the effectiveness of this program in meeting the key objective of reducing texting while driving. The program also influenced teenagers' willingness to take positive steps when faced with a driver who was texting. Future efforts should aim to influence social and peer norms. Therapeutic study, level IV.

Assessing Chinese coach drivers' fitness to drive: The development of a toolkit based on cognition measurements.

PubMed

Wang, Huarong; Mo, Xian; Wang, Ying; Liu, Ruixue; Qiu, Peiyu; Dai, Jiajun

2016-10-01

Road traffic accidents resulting in group deaths and injuries are often related to coach drivers' inappropriate operations and behaviors. Thus, the evaluation of coach drivers' fitness to drive is an important measure for improving the safety of public transportation. Previous related research focused on drivers' age and health condition. Comprehensive studies about commercial drivers' cognitive capacities are limited. This study developed a toolkit consisting of nine cognition measurements across driver perception/sensation, attention, and reaction. A total of 1413 licensed coach drivers in Jiangsu Province, China were investigated and tested. Results indicated that drivers with accident history within three years performed overwhelmingly worse (p<0.001) on dark adaptation, dynamic visual acuity, depth perception, attention concentration, attention span, and significantly worse (p<0.05) on reaction to complex tasks compared with drivers with clear accident records. These findings supported that in the assessment of fitness to drive, cognitive capacities are sensitive to the detection of drivers with accident proneness. We first developed a simple evaluation model based on the percentile distribution of all single measurements, which defined the normal range of "fit-to-drive" by eliminating a 5% tail of each measurement. A comprehensive evaluation model was later constructed based on the kernel principal component analysis, in which the eliminated 5% tail was calculated from on integrated index. Methods to categorizing qualified, good, and excellent coach drivers and criteria for evaluating and training Chinese coach drivers' fitness to drive were also proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Behavioral Economics of Drunk Driving

PubMed Central

Sloan, Frank A.; Eldred, Lindsey; Xu, Yanzhi

2014-01-01

This study investigates whether drinker-drivers attributes are associated with imperfect rationality or irrationality. Using data from eight U.S. cities, we determine whether drinker-drivers differ from other drinkers in cognitive ability, ignorance of driving while intoxicated (DWI) laws, have higher rates of time preference, are time inconsistent, and lack self-control on other measures. We find that drinker-drivers are relatively knowledgeable about DWI laws and do not differ on two of three study measures of cognitive ability from other drinkers. Drinker-drivers are less prone to plan events involving drinking, e.g., selecting a designated driver in advance of drinking, and are more impulsive. Furthermore, we find evidence in support of hyperbolic discounting. In particular, relative to non-drinker-drivers, the difference between short- and long-term discount rates is much higher for drinker-drivers than for other drinkers. Implications of our findings for public policy, including incapacitation, treatment, and educational interventions, are discussed. PMID:24603444

DriveID: safety innovation through individuation.

PubMed

Sawyer, Ben; Teo, Grace; Mouloua, Mustapha

2012-01-01

The driving task is highly complex and places considerable perceptual, physical and cognitive demands on the driver. As driving is fundamentally an information processing activity, distracted or impaired drivers have diminished safety margins compared with non- distracted drivers (Hancock and Parasuraman, 1992; TRB 1998 a & b). This competition for sensory and decision making capacities can lead to failures that cost lives. Some groups, teens and elderly drivers for example, have patterns of systematically poor perceptual, physical and cognitive performance while driving. Although there are technologies developed to aid these different drivers, these systems are often misused and underutilized. The DriveID project aims to design and develop a passive, automated face identification system capable of robustly identifying the driver of the vehicle, retrieve a stored profile, and intelligently prescribing specific accident prevention systems and driving environment customizations.

Guidelines For The Use, Design, And Construction Of Bridge Approach Slabs

DOT National Transportation Integrated Search

1999-11-01

Differential settlement at the roadway/bridge interface typically results in an abrupt grade change, causing driver discomfort impairing driver safety, and exerting potentially excessive impact traffic loading on the abutment. Bridge approach slabs a...

Design and evaluation of steering protection for avoiding collisions during a lane change.

PubMed

Itoh, Makoto; Inagaki, Toshiyuki

2014-01-01

This paper discusses the design of a driver assistance system for avoiding collisions with vehicles in blind spots. The following three types of support systems are compared: (1) a warning system that provides the driver with an auditory alert, (2) a 'soft' protection system that makes the steering wheel stiffer to tell the driver that a lane-change manoeuvre is not recommended and (3) a 'hard' protection system that cancels the driver's input and controls the tyre angle autonomously to prevent lane departure. The results of an experiment showed that the hard protection system was more effective for collision avoidance than either the warning or the soft protection system. The warning and soft protection systems were almost the same in terms of collision avoidance. The results suggest that the human-centred automation principle, which requires the human to have the final authority over the automation, can be violated depending on the context.

Understanding commercial truck drivers' decision-makin process concerning distracted driving.

PubMed

Swedler, David I; Pollack, Keshia M; Gielen, Andrea C

2015-05-01

A concurrent mixed methods design was used to explore personal and workplace factors, informed by the Theory of Planned Behavior, that affect truck drivers' decision-making about distracted driving on the job. Qualitative data were collected via semi-structured interviews with experts in truck safety and distracted driving, and quantitative data were collected via online survey of truck drivers in the United States. Findings from the interviews illustrated how drivers perceived distractions and the importance of supervisors enforcing organizational distracted driving policies. Survey results found that behavioral intentions were most important in regards to texting and crash and near-crash outcomes, while perceived norms from management best described the correlation between dispatch device use and negative crash-related outcomes. By using a mixed methods design, rather than two separate studies, these findings revealed nuanced differences into the influence of supervisors on distracted driving. Copyright © 2015 Elsevier Ltd. All rights reserved.

IGBT Gate Driver Upgrades to the HVCM at the SNS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Solley, Dennis J; Anderson, David E; Patel, Gunjan P

2012-01-01

The SNS at ORNL has been fully operational since 2006 and in September 2009, the design goal of 1MW of sustained beam power on target was achieved. Historically, the high voltage converter modulators (HVCM) have been a known problem area and, in order to reach another SNS milestone of 90% availability, a new gate driver was one of several areas targeted to improve the overall reliability of the HVCM systems. The drive capability and fault protection of the large IGBT modules in the HVCM were specifically addressed to improve IGBT switching characteristics and provide enhanced troubleshooting and monitoring capabilities formore » the critical IGBT/driver pair. This paper outlines the work involved; the result obtained and documents the driver s long-term performance. Enhanced features, designed to be used in conjunction with a new controller presently under development, will also be discussed.« less

Design of Low Inductance Switching Power Cell for GaN HEMT Based Inverter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gurpinar, Emre; Iannuzzo, Francesco; Yang, Yongheng

Here in this paper, an ultra-low inductance power cell is designed for a three-Level Active Neutral Point Clamped (3LANPC) based on 650 V gallium nitride (GaN) HEMT devices. The 3L-ANPC topology with GaN HEMT devices and the selected modulation scheme suitable for wide-bandgap (WBG) devices are presented. The commutation loops, which mainly contribute to voltage overshoots and increase of switching losses, are discussed. The ultra-low inductance power cell design based on a fourlayer Printed Circuit Board (PCB) with the aim to maximize the switching performance of GaN HEMTs is explained. The design of gate drivers for the GaN HEMT devicesmore » is presented. Parasitic inductance and resistance of the proposed design are extracted with finite element analysis and discussed. Common mode behaviours based on the SPICE model of the converter are analyzed. Experimental results on the designed 3L-ANPC with the output power of up to 1 kW are presented, which verifies the performance of the proposed design in terms of ultra-low inductance.« less

The influence of highly automated driving on the self-perception of drivers in the context of Conduct-by-Wire.

PubMed

Kauer, Michaela; Franz, Benjamin; Maier, Alexander; Bruder, Ralph

2015-01-01

Today, new driving paradigms are being introduced that aim to reduce the number of standalone driver assistance systems by combining these into one overarching system. This is done to reduce the demands on drivers but often leads to a higher degree of automation. Feasibility and driver behaviour are often the subject of studies, but this is contrasted by a lack of research into the influence of highly automated driving on the self-perception of drivers. This article begins to close this gap by investigating the influences of one highly automated driving concept--Conduct-by-Wire--on the self-perception of drivers via a combined driving simulator and interview study. The aim of this work is to identify changes in the role concept of drivers indicated by highly automated driving, to evaluate these changes from the drivers' point of view and to give suggestions of possible improvements to the design of highly automated vehicles.

A Comparison of Golf Shoe Designs Highlights Greater Ground Reaction Forces with Shorter Irons

PubMed Central

Worsfold, Paul; Smith, Neal A.; Dyson, Rosemary J.

2007-01-01

In an effort to reduce golf turf damage the traditional metal spike golf shoe has been redesigned, but shoe-ground biomechanical evaluations have utilised artificial grass surfaces. Twenty-four golfers wore three different golf shoe traction designs (traditional metal spikes, alternative spikes, and a flat-soled shoe with no additional traction) when performing shots with a driver, 3 iron and 7 iron. Ground action forces were measured beneath the feet by two natural grass covered force platforms. The maximum vertical force recorded at the back foot with the 3 iron and 7 iron was 0.82 BW (body weight) and at the front foot 1.1 BW approximately in both the metal spike and alternative spike golf shoe designs. When using the driver these maximal vertical values were 0.49 BW at the back foot and 0.84 BW at the front foot. Furthermore, as performance of the backswing and then downswing necessitates a change in movement direction the range of force generated during the complete swing was calculated. In the metal spike shoe the vertical force generated at the back foot with both irons was 0.67 BW and at the front foot 0.96 BW with the 3 iron and 0.92 BW with the 7 iron. The back foot vertical force generated with the driver was 0.33 BW and at the front foot 0.83 BW wearing the metal spike shoe. Results indicated the greater force generation with the irons. When using the driver the more horizontal swing plane associated with the longer club reduced vertical forces at the back and front foot. However, the mediolateral force generated across each foot in the metal and alternative spike shoes when using the driver was greater than when the irons were used. The coefficient of friction was 0. 62 at the back and front foot whichever shoe was worn or club used. Key pointsDuring the golf swing ground reaction forces at the golf shoe to natural grass turf interface were greater with irons than with the longer driver.In the golf swing maximal vertical forces were greater at the front (left) foot in the than at the back foot for a right handed golfer.Similar maximum vertical ground reaction forces were recorded with each club when a 8 mm metal spike golf shoe or an alternative spike golf shoe were worn.Force generation and coefficients of friction were similar for the alternative spike design and traditional metal seven spike golf shoe on natural grass turf.Data collection possible due to application of technical developments to golf from work on other natural turf based sports. PMID:24149482

Efficient Visible Light Communication Transmitters Based on Switching-Mode dc-dc Converters.

PubMed

Rodríguez, Juan; Lamar, Diego G; Aller, Daniel G; Miaja, Pablo F; Sebastián, Javier

2018-04-07

Visible light communication (VLC) based on solid-state lighting (SSL) is a promising option either to supplement or to substitute existing radio frequency (RF) wireless communication in indoor environments. VLC systems take advantage of the fast modulation of the visible light that light emitting diodes (LEDs) enable. The switching-mode dc-to-dc converter (SMC dc-dc ) must be the cornerstone of the LED driver of VLC transmitters in order to incorporate the communication functionality into LED lighting, keeping high power efficiency. However, the new requirements related to the communication, especially the high bandwidth that the LED driver must achieve, converts the design of the SMC dc-dc into a very challenging task. In this work, three different methods for achieving such a high bandwidth with an SMC dc-dc are presented: increasing the order of the SMC dc-dc output filter, increasing the number of voltage inputs, and increasing the number of phases. These three strategies are combinable and the optimum design depends on the particular VLC application, which determines the requirements of the VLC transmitter. As an example, an experimental VLC transmitter based on a two-phase buck converter with a fourth-order output filter will demonstrate that a bandwidth of several hundred kilohertz (kHz) can be achieved with output power levels close to 10 W and power efficiencies between 85% and 90%. In conclusion, the design strategy presented allows us to incorporate VLC into SSL, achieving high bit rates without damaging the power efficiency of LED lighting.

Efficient Visible Light Communication Transmitters Based on Switching-Mode dc-dc Converters

PubMed Central

2018-01-01

Visible light communication (VLC) based on solid-state lighting (SSL) is a promising option either to supplement or to substitute existing radio frequency (RF) wireless communication in indoor environments. VLC systems take advantage of the fast modulation of the visible light that light emitting diodes (LEDs) enable. The switching-mode dc-to-dc converter (SMCdc-dc) must be the cornerstone of the LED driver of VLC transmitters in order to incorporate the communication functionality into LED lighting, keeping high power efficiency. However, the new requirements related to the communication, especially the high bandwidth that the LED driver must achieve, converts the design of the SMCdc-dc into a very challenging task. In this work, three different methods for achieving such a high bandwidth with an SMCdc-dc are presented: increasing the order of the SMCdc-dc output filter, increasing the number of voltage inputs, and increasing the number of phases. These three strategies are combinable and the optimum design depends on the particular VLC application, which determines the requirements of the VLC transmitter. As an example, an experimental VLC transmitter based on a two-phase buck converter with a fourth-order output filter will demonstrate that a bandwidth of several hundred kilohertz (kHz) can be achieved with output power levels close to 10 W and power efficiencies between 85% and 90%. In conclusion, the design strategy presented allows us to incorporate VLC into SSL, achieving high bit rates without damaging the power efficiency of LED lighting. PMID:29642455

Modeling of driver's collision avoidance maneuver based on controller switching model.

PubMed

Kim, Jong-Hae; Hayakawa, Soichiro; Suzuki, Tatsuya; Hayashi, Koji; Okuma, Shigeru; Tsuchida, Nuio; Shimizu, Masayuki; Kido, Shigeyuki

2005-12-01

This paper presents a modeling strategy of human driving behavior based on the controller switching model focusing on the driver's collision avoidance maneuver. The driving data are collected by using the three-dimensional (3-D) driving simulator based on the CAVE Automatic Virtual Environment (CAVE), which provides stereoscopic immersive virtual environment. In our modeling, the control scenario of the human driver, that is, the mapping from the driver's sensory information to the operation of the driver such as acceleration, braking, and steering, is expressed by Piecewise Polynomial (PWP) model. Since the PWP model includes both continuous behaviors given by polynomials and discrete logical conditions, it can be regarded as a class of Hybrid Dynamical System (HDS). The identification problem for the PWP model is formulated as the Mixed Integer Linear Programming (MILP) by transforming the switching conditions into binary variables. From the obtained results, it is found that the driver appropriately switches the "control law" according to the sensory information. In addition, the driving characteristics of the beginner driver and the expert driver are compared and discussed. These results enable us to capture not only the physical meaning of the driving skill but the decision-making aspect (switching conditions) in the driver's collision avoidance maneuver as well.

A demonstration of motion base design alternatives for the National Advanced Driving Simulator

NASA Technical Reports Server (NTRS)

Mccauley, Michael E.; Sharkey, Thomas J.; Sinacori, John B.; Laforce, Soren; Miller, James C.; Cook, Anthony

1992-01-01

A demonstration of the capability of NASA's Vertical Motion Simulator to simulate two alternative motion base designs for the National Advanced Driving simulator (NADS) is reported. The VMS is located at ARC. The motion base conditions used in this demonstration were as follows: (1) a large translational motion base; and (2) a motion base design with limited translational capability. The latter had translational capability representative of a typical synergistic motion platform. These alternatives were selected to test the prediction that large amplitude translational motion would result in a lower incidence or severity of simulator induced sickness (SIS) than would a limited translational motion base. A total of 10 drivers performed two tasks, slaloms and quick-stops, using each of the motion bases. Physiological, objective, and subjective measures were collected. No reliable differences in SIS between the motion base conditions was found in this demonstration. However, in light of the cost considerations and engineering challenges associated with implementing a large translation motion base, performance of a formal study is recommended.

Wheat stress indicator model, Crop Condition Assessment Division (CCAD) data base interface driver, user's manual

NASA Technical Reports Server (NTRS)

Hansen, R. F. (Principal Investigator)

1981-01-01

The use of the wheat stress indicator model CCAD data base interface driver is described. The purpose of this system is to interface the wheat stress indicator model with the CCAD operational data base. The interface driver routine decides what meteorological stations should be processed and calls the proper subroutines to process the stations.

Cyclotrons and FFAG Accelerators as Drivers for ADS

DOE PAGES

Calabretta, Luciano; Méot, François

2015-01-01

Our review summarizes projects and studies on circular accelerators proposed for driving subcritical reactors. The early isochronous cyclotron cascades, proposed about 20 years ago, and the evolution of these layouts up to the most recent solutions or designs based on cyclotrons and fixed field alternating gradient accelerators, are reported. Additionally, the newest ideas and their prospects for development are discussed.

Does order matter? Investigating the effect of sequence on glance duration during on-road driving

PubMed Central

Roberts, Shannon C.; Reimer, Bryan; Mehler, Bruce

2017-01-01

Previous literature has shown that vehicle crash risks increases as drivers’ off-road glance duration increases. Many factors influence drivers’ glance duration such as individual differences, driving environment, or task characteristics. Theories and past studies suggest that glance duration increases as the task progresses, but the exact relationship between glance sequence and glance durations is not fully understood. The purpose of this study was to examine the effect of glance sequence on glance duration among drivers completing a visual-manual radio tuning task and an auditory-vocal based multi-modal navigation entry task. Eighty participants drove a vehicle on urban highways while completing radio tuning and navigation entry tasks. Forty participants drove under an experimental protocol that required three button presses followed by rotation of a tuning knob to complete the radio tuning task while the other forty participants completed the task with one less button press. Multiple statistical analyses were conducted to measure the effect of glance sequence on glance duration. Results showed that across both tasks and a variety of statistical tests, glance sequence had inconsistent effects on glance duration—the effects varied according to the number of glances, task type, and data set that was being evaluated. Results suggest that other aspects of the task as well as interface design effect glance duration and should be considered in the context of examining driver attention or lack thereof. All in all, interface design and task characteristics have a more influential impact on glance duration than glance sequence, suggesting that classical design considerations impacting driver attention, such as the size and location of buttons, remain fundamental in designing in-vehicle interfaces. PMID:28158301

A driving simulator study of driver performance on deceleration lanes.

PubMed

Calvi, A; Benedetto, A; De Blasiis, M R

2012-03-01

Deceleration lanes are important because they help drivers transition from high-speed lanes to low-speed ramps. Although they are designed to allow vehicles to depart the freeway safely and efficiently, many studies report high accident rates on exit ramps with the highest percentage of crashes taking place in deceleration lanes. This paper describes the results of a driving simulator study that focused on driving performance while approaching a divergence area and decelerating during the exiting maneuver. Three different traffic scenarios were simulated to analyze the influence of traffic volume on driving performance. Thirty drivers drove in the simulator in these scenarios while data on their lateral position, speed and deceleration were collected. Our results indicate there are considerable differences between the main assumptions of models generally used to design deceleration lanes and actual driving performance. In particular, diverging drivers begin to decelerate before arriving at the deceleration lane, causing interference with the main flow. Moreover, speeds recorded at the end of the deceleration lane exceed those for which the ramp's curves are designed; this creates risky driving conditions that could explain the high crash rates found in studies of exit ramps. Finally, statistical analyses demonstrate significant influences of traffic volume on some aspects of exiting drivers' performance: lower traffic volume results in elevated exiting speed and deceleration, and diverging drivers begin to decelerate earlier along the main lane when traffic volume is low. However, speeds at the end of the deceleration lane and the site of lane changing are not significantly influenced by traffic volume. Copyright © 2011 Elsevier Ltd. All rights reserved.

Performance of an SOI Boot-Strapped Full-Bridge MOSFET Driver, Type CHT-FBDR, under Extreme Temperatures

NASA Technical Reports Server (NTRS)

Patterson, Richard; Hammoud, Ahmad

2009-01-01

Electronic systems designed for use in deep space and planetary exploration missions are expected to encounter extreme temperatures and wide thermal swings. Silicon-based devices are limited in their wide-temperature capability and usually require extra measures, such as cooling or heating mechanisms, to provide adequate ambient temperature for proper operation. Silicon-On-Insulator (SOI) technology, on the other hand, lately has been gaining wide spread use in applications where high temperatures are encountered. Due to their inherent design, SOI-based integrated circuit chips are able to operate at temperatures higher than those of the silicon devices by virtue of reducing leakage currents, eliminating parasitic junctions, and limiting internal heating. In addition, SOI devices provide faster switching, consume less power, and offer improved radiation-tolerance. Very little data, however, exist on the performance of such devices and circuits under cryogenic temperatures. In this work, the performance of an SOI bootstrapped, full-bridge driver integrated circuit was evaluated under extreme temperatures and thermal cycling. The investigations were carried out to establish a baseline on the functionality and to determine suitability of this device for use in space exploration missions under extreme temperature conditions.

How to create successful Open Hardware projects — About White Rabbits and open fields

NASA Astrophysics Data System (ADS)

van der Bij, E.; Arruat, M.; Cattin, M.; Daniluk, G.; Gonzalez Cobas, J. D.; Gousiou, E.; Lewis, J.; Lipinski, M. M.; Serrano, J.; Stana, T.; Voumard, N.; Wlostowski, T.

2013-12-01

CERN's accelerator control group has embraced ''Open Hardware'' (OH) to facilitate peer review, avoid vendor lock-in and make support tasks scalable. A web-based tool for easing collaborative work was set up and the CERN OH Licence was created. New ADC, TDC, fine delay and carrier cards based on VITA and PCI-SIG standards were designed and drivers for Linux were written. Often industry was paid for developments, while quality and documentation was controlled by CERN. An innovative timing network was also developed with the OH paradigm. Industry now sells and supports these designs that find their way into new fields.

The Influence of Motion Cues on Driver-Vehicle Performance in a Simulator

NASA Technical Reports Server (NTRS)

Repa, B. S.; Leucht, P. M.; Wierwille, W. W.

1981-01-01

Four different motion base configurations were studied on driving simulator. Differently responding vehicles were simulated on each motion configurations and the effects of the vehicle characteristics on driver vehicle system performance, driver control activity, and driver opinion ratings of vehicle performance during driving are compared for different motion configurations. Data show that: (1)) the effects of changes in vehicle characteristics on the different objective and subjective measures of driver vehicle performance are not disguised by the lack of physical motion; (2) fixed base simulator can be used to draw inferences despite the lack of motion; (3) the presence of motion tends to reduce path keeping errors and driver control activity; (4) roll and yaw motions are recommended because of their marked influence on driver vehicle performance (5) the importance of motion increases as the driving maneuvers become more extreme.

Real-time driver fatigue detection based on face alignment

NASA Astrophysics Data System (ADS)

Tao, Huanhuan; Zhang, Guiying; Zhao, Yong; Zhou, Yi

2017-07-01

The performance and robustness of fatigue detection largely decrease if the driver with glasses. To address this issue, this paper proposes a practical driver fatigue detection method based on face alignment at 3000 FPS algorithm. Firstly, the eye regions of the driver are localized by exploiting 6 landmarks surrounding each eye. Secondly, the HOG features of the extracted eye regions are calculated and put into SVM classifier to recognize the eye state. Finally, the value of PERCLOS is calculated to determine whether the driver is drowsy or not. An alarm will be generated if the eye is closed for a specified period of time. The accuracy and real-time on testing videos with different drivers demonstrate that the proposed algorithm is robust and obtain better accuracy for driver fatigue detection compared with some previous method.

Critical review and analysis of the impact of the physical infrastructure on the driving ability, performance, and safety of older adults.

PubMed

Bohr, Paula Christine

2008-01-01

Literature on the impact of physical infrastructure on older adult safe driving performance was reviewed in 2005 as part of the American Occupational Therapy Association's Evidence-Based Literature Review Project. Existing guidelines for driving environments, related to changes in visual, cognitive, and psychomotor abilities associated with the aging process (as published in the Highway Design Handbook for Older Drivers and Pedestrians, Federal Highway Administration, 2001), are exhaustive, but the authors made no attempt to critically assess the strength of the study design or level of evidence. In laboratory studies since 1999, the interventions lacked applicability to real-life driving environments. Further investigation of the effectiveness of best practice interventions and how the driving environment can better accommodate the needs of older drivers is needed. Occupational therapy interventions that focus on the occupation of driving and compensation and education strategies that allow older adults to drive safely as long as possible are included.

Bridgeless SEPIC PFC Converter for Multistring LED Driver

NASA Astrophysics Data System (ADS)

Jha, Aman; Singh, Bhim

2018-05-01

This paper deals with Power Factor Correction (PFC) in Low Voltage High Current (LVHC) multi-string light emitting diode (LED) using a bridgeless (BL) single ended primary inductance converter (SEPIC). This application is designed for large area LED lighting with illumination control. A multi-mode LED dimming technique is used for the lighting control. The BL-SEPIC PFC converter is used as a load emulator for high power factor. The regulated low voltage from flyback converter is a source power to the synchronous buck converters for multi-string LED driver and forced cooling system for LED junction. The BL-SEPIC PFC converter inductor design is based on Discontinuous Inductor Current Modes (DICM) which provides good PFC at low cost. Test results are found quite satisfactory for universal input AC (90-265 V). There is significant improvement in the power factor and input current Total Harmonic Distortion (THD) with good margin of harmonic limits for lighting IEC 61000-3-2 Class C.

Parametric Cost Models for Space Telescopes

NASA Technical Reports Server (NTRS)

Stahl, H. Philip; Henrichs, Todd; Dollinger, Courtney

2010-01-01

Multivariable parametric cost models for space telescopes provide several benefits to designers and space system project managers. They identify major architectural cost drivers and allow high-level design trades. They enable cost-benefit analysis for technology development investment. And, they provide a basis for estimating total project cost. A survey of historical models found that there is no definitive space telescope cost model. In fact, published models vary greatly [1]. Thus, there is a need for parametric space telescopes cost models. An effort is underway to develop single variable [2] and multi-variable [3] parametric space telescope cost models based on the latest available data and applying rigorous analytical techniques. Specific cost estimating relationships (CERs) have been developed which show that aperture diameter is the primary cost driver for large space telescopes; technology development as a function of time reduces cost at the rate of 50% per 17 years; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; and increasing mass reduces cost.

An empirical assessment of driver motivation and emotional states in perceived safety margins under varied driving conditions.

PubMed

Zhang, Yu; Kaber, David B

2013-01-01

Motivation models in driving behaviour postulate that driver motives and emotional states dictate risk tolerance under various traffic conditions. The present study used time and driver performance-based payment systems to manipulate motivation and risk-taking behaviour. Ten participants drove to a predefined location in a simulated driving environment. Traffic patterns (density and velocity) were manipulated to cause driver behaviour adjustments due to the need to conform with the social norms of the roadway. The driving environment complexity was investigated as a mediating factor in risk tolerance. Results revealed the performance-based payment system to closely relate to risk-taking behaviour as compared with the time-based payment system. Drivers conformed with social norms associated with specific traffic patterns. Higher roadway complexity led to a more conservative safety margins and speeds. This research contributes to the further development of motivational models of driver behaviour. This study provides empirical justification for two motivation factors in driver risk-taking decisions, including compliance with social norm and emotions triggered by incentives. Environment complexity was identified as a mediating factor in motivational behaviour model. This study also recommended safety margin measures sensitive to changes in driver risk tolerance.

Guidelines and Recommendations to Accommodate Older Drivers and Pedestrians

DOT National Transportation Integrated Search

2001-05-01

This project updated, revised, and expanded the scope of the "Older Driver Highway Design Handbook" published by the Federal Highway Administration (FHWA) in 1998. Development of the updated Handbook (FHWA-RD-01-103) was complemented by a technology ...

Guidelines and Recommendations to Accommodate Older Drivers and Pedestrians

DOT National Transportation Integrated Search

2001-10-01

This project updated, revised, and expanded the scope of the "Older Driver Highway Design Handbook" published by the Federal Highway Administration (FHWA) in 1998. Development of the updated Handbook (FHWA-RD-01-103) was complemented by a technology ...

Investigation Of Alternative Displays For Side Collision Avoidance Systems, Final Report

DOT National Transportation Integrated Search

1996-12-01

DRIVER-VEHICLE INTERFACE OR DVI, HUMAN FACTORS, DRIVER PREFERENCES, INTELLIGENT VEHICLE INITIATIVE OR IVI : SIDE COLLISION AVOIDANCE SYSTEMS (SCAS) ARE DESIGNED TO WARN OF IMPENDING COLLISIONS AND CAN DETECT NOT ONLY ADJACENT VEHICLES BUT VEHICLES...

On an efficient and effective intelligent transportation system (ITS) safety and traffic efficiency application with corresponding driver behavior

NASA Astrophysics Data System (ADS)

Ekedebe, Nnanna; Yu, Wei; Lu, Chao

2015-06-01

Driver distraction could result in safety compromises attributable to distractions from in-vehicle equipment usage [1]. The effective design of driver-vehicle interfaces (DVIs) and other human-machine interfaces (HMIs) together with their usability, and accessibility while driving become important [2]. Driving distractions can be classified as: visual distractions (any activity that takes your eyes away from the road), cognitive distraction (any activity that takes your mind away from the course of driving), and manual distractions (any activity that takes your hands away from the steering wheel [2]). Besides, multitasking during driving is a distractive activity that can increase the risks of vehicular accidents. To study the driver's behaviors on the safety of transportation system, using an in-vehicle driver notification application, we examined the effects of increasing driver distraction levels on the evaluation metrics of traffic efficiency and safety by using two types of driver models: young drivers (ages 16-25 years) and middle-age drivers (ages 30-45 years). Our evaluation data demonstrates that as a drivers distraction level is increased, less heed is given to change route directives from the in-vehicle on-board unit (OBU) using textual, visual, audio, and haptic notifications. Interestingly, middle-age drivers proved more effective/resilient in mitigating the negative effects of driver distraction over young drivers [2].

Research On Vehicle-Based Driver Status/Performance Monitoring; Development, Validation, And Refinement Of Algorithms For Detection Of Driver Drowsiness, Final Report

DOT National Transportation Integrated Search

1994-12-01

THIS REPORT SUMMARIZES THE RESULTS OF A 3-YEAR RESEARCH PROJECT TO DEVELOP RELIABLE ALGORITHMS FOR THE DETECTION OF MOTOR VEHICLE DRIVER IMPAIRMENT DUE TO DROWSINESS. THESE ALGORITHMS ARE BASED ON DRIVING PERFORMANCE MEASURES THAT CAN POTENTIALLY BE ...

The impact of raising the minimum drinking age on driver fatalities.

PubMed

MacKinnon, D P; Woodward, J A

1986-12-01

Time series analysis was used to obtain statistical tests of the impact of raising the drinking age on monthly driver fatalities in Illinois, Michigan, and Massachusetts. A control series design permitted comparison between younger drivers (21 or less years) and older drivers (25 and older) within states where the minimum drinking age was raised. Since the two groups share the same driving conditions, it was important to demonstrate that any reduction in fatalities was limited to the young age group within which the drinking age change occurred. In addition, control states were selected to permit a comparison between driver fatalities of the young age group (21 or less) in states with the law change and young drivers in states without the law change. Significant immediate reductions in fatalities among 21 and younger drivers in Illinois and Michigan were observed after these states raised their minimum drinking age. No significant reductions in any control series were observed. A linear decrease in young driver fatalities was observed after the drinking age was raised in Massachusetts. There was also a significant linear decrease in young driver fatalities in the Connecticut control series, perhaps due to increasing awareness among young drivers of the dangers of drinking and driving.

Older drivers, the age factor in traffic safety

DOT National Transportation Integrated Search

1989-02-01

The report presents an overview of the traffic safety problem in relation to the age of the driver. Emphasis is placed on the older drivers. Crash involvement rates are developed for each age group of drivers based on their estimated annual travel. T...

Supporting anticipation in driving through attentional and interpretational in-vehicle displays.

PubMed

Stahl, Patrick; Donmez, Birsen; Jamieson, Greg A

2016-06-01

This paper evaluates two different types of in-vehicle interfaces to support anticipation in driving: one aids attention allocation and the other aids interpretation of traffic in addition to attention allocation. Anticipation is a competency that has been shown to facilitate safety and eco-driving through the efficient positioning of a vehicle for probable, upcoming changes in traffic. This competency has been shown to improve with driving experience. In an earlier simulator study, we showed that compared to novice drivers, experienced drivers exhibited a greater number of timely actions to avoid upcoming traffic conflicts. In this study, we seek to facilitate anticipation in general and for novice drivers in particular, who appear to lack the competency. We hypothesize that anticipation depends on two major steps and that it can be supported by aiding each: (1) conscious perception of relevant cues, and (2) effective processing of these cues to create a situational assessment as a basis for anticipation of future developments. We conducted a simulator experiment with 24 experienced and 24 novice drivers to evaluate two interfaces that were designed to aid the two hypothesized steps of anticipation. The attentional interface was designed to direct attention toward the most relevant cue. The interpretational interface represented several cues, and in addition to directing attention also aimed to aid sense-making of these cues. The results confirmed our hypothesis that novice drivers' anticipation performance, as measured through timely actions to avoid upcoming traffic conflicts, would be improved with either interface type. However, results contradicted our expectation that novice drivers would obtain larger improvements with the interpretational interface. Experienced drivers performed better than novice drivers to begin with and did not show any statistically significant improvements with either interface. Both interfaces improved anticipation performance for novice drivers. Future research should evaluate the effectiveness of these interfaces in a wider variety of driving conditions, such as when the driver is multitasking. Copyright © 2016 Elsevier Ltd. All rights reserved.

Young drivers and their cars: Safe and sound or the perfect storm?

PubMed

Oviedo-Trespalacios, Oscar; Scott-Parker, Bridie

2018-01-01

Consistent with the experiences in high-income countries, young drivers remain overrepresented in road trauma statistics in low- and middle-income countries. This article pursues the emerging interest of approaching the young driver problem from a systems thinking perspective in order to design and deliver robust countermeasures. Specifically, the focus of this paper is the cars driven by young drivers. The study of vehicles' characteristics and their interaction with driving behaviour is, more often than not, considered a minor concern when developing countermeasures in young drivers' safety not only in developed nations, but especially in developing nations. Participants completed an online survey containing the 44-item Behaviour of Young Novice Drivers Scale Spanish version (BYNDS-Sp), in addition to providing information regarding their vehicle, any crash involvement, and driving offences. Based on the vehicle model information, the assessment of vehicle safety was conducted for three safety programs (ANCAP, Latin NCAP, U.S. NCAP). Young drivers in Colombia reported a breadth of risky driving behaviours worth targeting in broader interventions. For example, interventions can target speeding, particularly as three quarters of the participants drove small-medium cars associated with poorer road safety outcomes. Moreover, risky driving exposure was highly prevalent amongst the young driver participants, demonstrating the need for them to be driving the safest vehicles possible. It is noteworthy that few cars were able to be assessed by the Latin NCAP (with half of the cars rated having only 0-2 star ratings), and that there was considerable discrepancy between ANCAP, U.S. NCAP, and Latin NCAP ratings. The need for system-wide strategies to increase young driver road safety-such as improved vehicle safety-is vital to improve road safety outcomes in jurisdictions such as Colombia. Such improvements may also require systemic changes such as enhanced vehicle safety rating scales and investigation of the nature of vehicles sold in developing nations, particularly as these vehicles typically contain fewer safety features than their counterparts sold in developed nations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Steering disturbance rejection using a physics-based neuromusculoskeletal driver model

NASA Astrophysics Data System (ADS)

Mehrabi, Naser; Sharif Razavian, Reza; McPhee, John

2015-10-01

The aim of this work is to develop a comprehensive yet practical driver model to be used in studying driver-vehicle interactions. Drivers interact with their vehicle and the road through the steering wheel. This interaction forms a closed-loop coupled human-machine system, which influences the driver's steering feel and control performance. A hierarchical approach is proposed here to capture the complexity of the driver's neuromuscular dynamics and the central nervous system in the coordination of the driver's upper extremity activities, especially in the presence of external disturbance. The proposed motor control framework has three layers: the first (or the path planning) plans a desired vehicle trajectory and the required steering angles to perform the desired trajectory; the second (or the musculoskeletal controller) actuates the musculoskeletal arm to rotate the steering wheel accordingly; and the final layer ensures the precision control and disturbance rejection of the motor control units. The physics-based driver model presented here can also provide insights into vehicle control in relaxed and tensed driving conditions, which are simulated by adjusting the driver model parameters such as cognition delay and muscle co-contraction dynamics.

Design of 3x3 Focusing Array for Heavy Ion Driver Final Report on CRADA TC-02082-04

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martovetsky, N.

This memo presents a design of a 3x3 quadrupole array for HIF. It contains 3 D magnetic field computations of the array build with racetrack coils with and without different shields. It is shown that it is possible to have a low error magnetic field in the cells and shield the stray fields to acceptable levels. The array design seems to be a practical solution to any size array for future multi-beam heavy ion fusion drivers.

Integration of ATIS and crash avoidance in-vehicle information : preliminary simulator study

DOT National Transportation Integrated Search

1999-12-01

This study investigated three issues relevant to Advanced Traveler Information System (ATIS) design: (1) the influence of an ATIS on driver performance in reduced visibility conditions, (2) the influence of an ATIS on drivers' reactions to unexpected...

Guidelines and recommendations to accommodate older driver and pedestrians

DOT National Transportation Integrated Search

2001-05-01

This project updated, revised, and expanded the scope of the Older Driver Highway Design Handbook published by FHWA in 1998. Development of the updated Handbook (FHWA-RD-01-103) was complemented by a technology transfer initiative to make practitione...

Note: An improved solenoid driver valve for miniature shock tubes.

PubMed

Lynch, P T

2016-05-01

A solenoid driver valve has been built to improve the operating performance of diaphragmless shock tubes, which are used for high pressure, high temperature chemical kinetics, and fluid mechanics studies. For shock tube driver application, the most important characteristics are those of sealing, strength, and quality of the generated shock waves and repeatability of opening characteristics and therefore subsequent post-shock conditions. The main features of the new driver valve are a face o-ring sealing design of the valve, the large internal volume, and through inserts near the solenoid core: adjustable opening characteristics of the valve.

An approach to vehicle design: In-depth audit to understand the needs of older drivers.

PubMed

Karali, Sukru; Mansfield, Neil J; Gyi, Diane E

2017-01-01

The population of older people continues to increase around the world, and this trend is expected to continue; the population of older drivers is increasing accordingly. January 2012 figures from the DVLA in the UK stated that there were more than 15 million drivers aged over 60; more than 1 million drivers were aged over 80. There is a need for specific research tools to understand and capture how all users interact with features in the vehicle cabin e.g. controls and tasks, including the specific needs of the increasingly older driving population. This paper describes an in-depth audit that was conducted to understand how design of the vehicle cabin impacts on comfort, posture, usability, health and wellbeing in older drivers. The sample involved 47 drivers (38% female, 62% male). The age distribution was: 50-64 (n = 12), 65-79 (n = 20), and those 80 and over (n = 15). The methodology included tools to capture user experience in the vehicle cabin and functional performance tests relevant to specific driving tasks. It is shown that drivers' physical capabilities reduce with age and that there are associated difficulties in setting up an optimal driving position such that some controls cannot be operated as intended, and many adapt their driving cabins. The cabin set-up process consistently began with setting up the seat and finished with operation of the seat belt. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Microcontroller based driver alertness detection systems to detect drowsiness

NASA Astrophysics Data System (ADS)

Adenin, Hasibah; Zahari, Rahimi; Lim, Tiong Hoo

2018-04-01

The advancement of embedded system for detecting and preventing drowsiness in a vehicle is a major challenge for road traffic accident systems. To prevent drowsiness while driving, it is necessary to have an alert system that can detect a decline in driver concentration and send a signal to the driver. Studies have shown that traffc accidents usually occur when the driver is distracted while driving. In this paper, we have reviewed a number of detection systems to monitor the concentration of a car driver and propose a portable Driver Alertness Detection System (DADS) to determine the level of concentration of the driver based on pixelated coloration detection technique using facial recognition. A portable camera will be placed at the front visor to capture facial expression and the eye activities. We evaluate DADS using 26 participants and have achieved 100% detection rate with good lighting condition and a low detection rate at night.

Obstructive sleep apnea among commercial motor vehicle drivers: using evidence-based practice to identify risk factors.

PubMed

Olszewski, Kimberly; Wolf, Debra

2013-11-01

Commercial motor vehicle driving is a hazardous occupation, having the third highest fatality rate among common U.S. jobs. Among the estimated 14 million U.S. commercial motor vehicle drivers, the prevalence of obstructive sleep apnea is reported to be 17% to 28%. Despite the identified increased prevalence of obstructive sleep apnea among commercial motor vehicle drivers, federal law does not require that they be screened for obstructive sleep apnea. This article presents an evidence-based practice change project; the authors developed, implemented, and evaluated a screening program to identify commercial motor vehicle drivers' risk for obstructive sleep apnea during commercial driver medical examinations. The results of this practice change indicated screening for obstructive sleep apnea during the commercial driver medical examination led to improved identification of obstructive sleep apnea risk among commercial motor vehicle drivers and should be a clinical standard in occupational health clinics. Copyright 2013, SLACK Incorporated.

Driver's mental workload prediction model based on physiological indices.

PubMed

Yan, Shengyuan; Tran, Cong Chi; Wei, Yingying; Habiyaremye, Jean Luc

2017-09-15

Developing an early warning model to predict the driver's mental workload (MWL) is critical and helpful, especially for new or less experienced drivers. The present study aims to investigate the correlation between new drivers' MWL and their work performance, regarding the number of errors. Additionally, the group method of data handling is used to establish the driver's MWL predictive model based on subjective rating (NASA task load index [NASA-TLX]) and six physiological indices. The results indicate that the NASA-TLX and the number of errors are positively correlated, and the predictive model shows the validity of the proposed model with an R 2 value of 0.745. The proposed model is expected to provide a reference value for the new drivers of their MWL by providing the physiological indices, and the driving lesson plans can be proposed to sustain an appropriate MWL as well as improve the driver's work performance.

77 FR 12907 - Visual-Manual NHTSA Driver Distraction Guidelines for In-Vehicle Electronic Devices

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-02

... impact of task performance while driving on driving safety and time-based acceptance criteria for... feedback). The proposed NHTSA Guidelines list certain secondary, non-driving related tasks that, based on... cannot be used by the driver to perform such tasks while the driver is driving. For all other secondary...

Major Design Drivers for LEO Space Surveillance in Europe and Solution Concepts

NASA Astrophysics Data System (ADS)

Krag, Holger; Flohrer, Tim; Klinkrad, Heiner

Europe is preparing for the development of an autonomous system for space situational aware-ness. One important segment of this new system will be dedicated to surveillance and tracking of space objects in Earth orbits. First concept and capability analysis studies have led to a draft system proposal. This proposal foresees, in a first deployment step, a groundbased system consisting of radar sensors and a network of optical telescopes. These sensors will be designed to have the capability of building up and maintaining a catalogue of space objects. A number of related services will be provided, including collision avoidance and the prediction of uncontrolled reentry events. Currently, the user requirements are consolidated, defining the different services, and the related accuracy and timeliness of the derived products. In this consolidation process parameters like the lower diameter limit above which catalogue coverage is to be achieved, the degree of population coverage in various orbital regions and the accuracy of the orbit data maintained in the catalogue are important design drivers for the selection of number and location of the sensors, and the definition of the required sensor performance. Further, the required minimum time for the detection of a manoeuvre, a newly launched object or a fragmentation event, significantly determines the required surveillance performance. In the requirement consolidation process the performance to be specified has to be based on a careful analysis which takes into account accuracy constraints of the services to be provided, the technical feasibility, complexity and costs. User requirements can thus not be defined with-out understanding the consequences they would pose on the system design. This paper will outline the design definition process for the surveillance and tracking segment of the European space situational awareness system. The paper will focus on the low-Earth orbits (LEO). It will present the core user requirements and the definition of the derived services. The de-sired performance parameters will be explained together with presenting their rationale and justification. This will be followed by an identification of the resulting major design drivers. The influence of these drivers on the system design will be analysed, including limiting object diameter, population coverage, orbit maintenance accuracy, and the minimum time to detect events like manoeuvres or breakups. The underlying simulation and verification concept will be explained. Finally, a first compilation of performance parameters for the surveillance and tracking segment will be presented and discussed.

The impact of driver age on lost life years for other road users in France: A population based study of crash-involved road users.

PubMed

Lafont, Sylviane; Amoros, Emmanuelle; Gadegbeku, Blandine; Chiron, Mireille; Laumon, Bernard

2008-01-01

One of the concerns in road safety is the threat older drivers may pose to other road users. Using the rate of lost life years, the present study provides a public health approach to quantify this potential threat. A total of 1570686 motorised vehicle drivers or motorcycle riders and 652246 non-drivers, i.e. vehicle passengers, pedestrians and cyclists involved in injury crashes in France between 1996 and 2004, were included in a population based cross-sectional study. Fatality rates and rate of lost life years for each crash-involved driver age class were calculated for the drivers themselves and for other road users. The study has shown a significant reduction in the rate of lost life years for crash-involved other road users (whether passengers, pedestrians, cyclists or opposing drivers) as driver age increases. Other road users lost half as many years of life when involved in crashes with drivers aged over 85 than with drivers under 65 (1.26 and 2.32 per 100 expected remaining life years, respectively). Our findings suggest that among road users involved in injury crashes, older drivers are less dangerous for the other road users. By attributing other road users' lost life years to each driver age, this study represents a new contribution to the debate about ageing and road safety.

Comparison of human driver dynamics in simulators with complex and simple visual displays and in an automobile on the road

NASA Technical Reports Server (NTRS)

Mcruer, D. T.; Klein, R. H.

1975-01-01

As part of a comprehensive program exploring driver/vehicle system response in lateral steering tasks, driver/vehicle system describing functions and other dynamic data have been gathered in several milieu. These include a simple fixed base simulator with an elementary roadway delineation only display; a fixed base statically operating automobile with a terrain model based, wide angle projection system display; and a full scale moving base automobile operating on the road. Dynamic data with the two fixed base simulators compared favorably, implying that the impoverished visual scene, lack of engine noise, and simplified steering wheel feel characteristics in the simple simulator did not induce significant driver dynamic behavior variations. The fixed base vs. moving base comparisons showed substantially greater crossover frequencies and phase margins on the road course.

Nighttime driving and fatal crash involvement of teenagers.

PubMed

Williams, A F

1985-02-01

Data from the 1977 National Personal Transportation Survey and from the Fatal Accident Reporting System were used to compute mileage-based fatal crash involvement rates of drivers, by age, sex, and time of day. Teenagers drive less than older drivers but do more of their driving at night. They have much higher numbers of drivers in fatal crashes based on miles driven than do older drivers; their nighttime rates are particularly high. Sixteen year olds, especially males, have by far the highest fatal crash rates per mile, both nighttime and daytime. More widespread adoption of driving curfew laws would very likely produce substantial reductions in fatalities involving 16 yr old drivers.

Adult Competency Education Kit. Basic Skills in Speaking, Math, and Reading for Employment. Part Q. ACE Competency Based Job Descriptions: #91--Meat Cutter; #92--Shipping Clerk; #93--Long Haul Truck Driver; #94--Truck Driver--Light.

ERIC Educational Resources Information Center

San Mateo County Office of Education, Redwood City, CA. Career Preparation Centers.

This fourteenth of fifteen sets of Adult Competency Education (ACE) Based Job Descriptions in the ACE kit contains job descriptions for Meat Cutter, Shipping Clerk, Long Haul Truck Driver, and Truck Driver--Light. Each begins with a fact sheet that includes this information: occupational title, D.O.T. code, ACE number, career ladder, D.O.T.…

Naturalistic distraction and driving safety in older drivers.

PubMed

Aksan, Nazan; Dawson, Jeffrey D; Emerson, Jamie L; Yu, Lixi; Uc, Ergun Y; Anderson, Steven W; Rizzo, Matthew

2013-08-01

In this study, we aimed to quantify and compare performance of middle-aged and older drivers during a naturalistic distraction paradigm (visual search for roadside targets) and to predict older drivers performance given functioning in visual, motor, and cognitive domains. Distracted driving can imperil healthy adults and may disproportionally affect the safety of older drivers with visual, motor, and cognitive decline. A total of 203 drivers, 120 healthy older (61 men and 59 women, ages 65 years and older) and 83 middle-aged drivers (38 men and 45 women, ages 40 to 64 years), participated in an on-road test in an instrumented vehicle. Outcome measures included performance in roadside target identification (traffic signs and restaurants) and concurrent driver safety. Differences in visual, motor, and cognitive functioning served as predictors. Older drivers identified fewer landmarks and drove slower but committed more safety errors than did middle-aged drivers. Greater familiarity with local roads benefited performance of middle-aged but not older drivers.Visual cognition predicted both traffic sign identification and safety errors, and executive function predicted traffic sign identification over and above vision. Older adults are susceptible to driving safety errors while distracted by common secondary visual search tasks that are inherent to driving. The findings underscore that age-related cognitive decline affects older drivers' management of driving tasks at multiple levels and can help inform the design of on-road tests and interventions for older drivers.

Laser targets compensate for limitations in inertial confinement fusion drivers

NASA Astrophysics Data System (ADS)

Kilkenny, J. D.; Alexander, N. B.; Nikroo, A.; Steinman, D. A.; Nobile, A.; Bernat, T.; Cook, R.; Letts, S.; Takagi, M.; Harding, D.

2005-10-01

Success in inertial confinement fusion (ICF) requires sophisticated, characterized targets. The increasing fidelity of three-dimensional (3D), radiation hydrodynamic computer codes has made it possible to design targets for ICF which can compensate for limitations in the existing single shot laser and Z pinch ICF drivers. Developments in ICF target fabrication technology allow more esoteric target designs to be fabricated. At present, requirements require new deterministic nano-material fabrication on micro scale.

The characteristics and use patterns of all-terrain vehicle drivers in the United States.

PubMed

Rodgers, G B

1999-07-01

The consent decrees between the US Consumer Product Safety Commission and the major distributors of all-terrain vehicles (ATV), which were designed to address ATV-related injuries and deaths, expired in April, 1998. While national estimates of nonfatal and fatal injuries involving ATVs declined after the consent decrees went into effect 10 years ago, the injury estimates have stabilized in recent years. To gain a better understanding of current ATV use patterns, the CPSC sponsored a national probability survey of ATV drivers in the fall of 1997. The survey was designed to collect information about the characteristics and use patterns of ATV drivers and to quantify the numbers and types of ATVs in use. It employed a single stage list-assisted random-digit-dial sample design. This article describes the results of the survey, and discusses long term ATV usage trends.

[Artefacts of questionnaire-based psychological testing of drivers].

PubMed

Łuczak, Anna; Tarnowski, Adam

2014-01-01

The purpose of this article is to draw attention to a significant role of social approval variable in the qustionnaire-based diagnosis of drivers' psychological aptitude. Three questionnaires were used: Formal Characteristics of Behavior - Temperament Inventory (FCB-TI), Eysenck Personality Questionnaire (EPQ-R(S) and Impulsiveness Questionnaire (Impulsiveness, Venturesomeness, Empathy - IVE). Three groups of drivers were analyzed: professional "without crashes" (N = 46), nonprofessional "without crashes" (N = 75), and nonprofessional "with crashes" (N = 75). Nonprofessional drivers "without crashes" significantly stood up against other drivers. Their personality profile, indicating a significantly utmost perseveration, emotional reactivity, neuroticism, impulsiveness and the lowest endurance did not fit in to the requirements to be met by drivers. The driver safety profile was characteristic of professional drivers (the lowest level of perseveration, impulsiveness and neuroticism and the highest level of endurance). Similar profile occurred among nonprofessional drivers--the offenders of road crashes. Compared to the nonprofessional "without crashes" group, professional drivers and offenders of road crashes were also characterized by a significantly higher score on the Lie scale, determining the need for social approval. This is likely to result from the study procedure according to which the result of professional drivers testing had an impact on a possible continuity of their job and that of nonprofessional drivers "with crashes" decided about possible recovery of the driving license. The variable of social approval can be a significant artifact in the study of psychological drivers' testing and reduce the reliability of the results of questionnaire methods.

Real-time qualitative reasoning for telerobotic systems

NASA Technical Reports Server (NTRS)

Pin, Eancois G.

1993-01-01

This paper discusses the sensor-based telerobotic driving of a car in a-priori unknown environments using 'human-like' reasoning schemes implemented on custom-designed VLSI fuzzy inferencing boards. These boards use the Fuzzy Set theoretic framework to allow very vast (30 kHz) processing of full sets of information that are expressed in qualitative form using membership functions. The sensor-based and fuzzy inferencing system was incorporated on an outdoor test-bed platform to investigate two control modes for driving a car on the basis of very sparse and imprecise range data. In the first mode, the car navigates fully autonomously to a goal specified by the operator, while in the second mode, the system acts as a telerobotic driver's aid providing the driver with linguistic (fuzzy) commands to turn left or right, speed up, slow down, stop, or back up depending on the obstacles perceived by the sensors. Indoor and outdoor experiments with both modes of control are described in which the system uses only three acoustic range (sonar) sensor channels to perceive the environment. Sample results are presented that illustrate the feasibility of developing autonomous navigation modules and robust, safety-enhancing driver's aids for telerobotic systems using the new fuzzy inferencing VLSI hardware and 'human-like' reasoning schemes.

Effectiveness of mandatory license testing for older drivers in reducing crash risk among urban older Australian drivers.

PubMed

Langford, Jim; Fitzharris, Michael; Koppel, Sjaanie; Newstead, Stuart

2004-12-01

Most licensing jurisdictions in Australia maintain mandatory assessment programs targeting older drivers, whereby a driver reaching a specified age is required to prove his or her fitness to drive through medical assessment and/or on-road testing. Previous studies both in Australia and elsewhere have consistently failed to demonstrate that age-based mandatory assessment results in reduced crash involvement for older drivers. However studies that have based their results upon either per-population or per-driver crash rates fail to take into account possible differences in driving activity. Because some older people maintain their driving licenses but rarely if ever drive, the proportion of inactive license-holders might be higher in jurisdictions without mandatory assessment relative to jurisdictions with periodic license assessment, where inactive drivers may more readily either surrender or lose their licenses. The failure to control for possible differences in driving activity across jurisdictions may be disguising possible safety benefits associated with mandatory assessment. The current study compared the crash rates of drivers in Melbourne, Australia, where there is no mandatory assessment and Sydney, Australia, where there is regular mandatory assessment from 80 years of age onward. The crash rate comparisons were based on four exposure measures: per population, per licensed driver, per distance driven, and per time spent driving. Poisson regression analysis incorporating an offset to control for inter-jurisdictional road safety differences indicated that there was no difference in crash risk for older drivers based on population. However drivers aged 80 years and older in the Sydney region had statistically higher rates of casualty crash involvement than their Melbourne counterparts on a per license issued basis (RR: 1.15, 1.02-1.29, p=0.02) and time spent driving basis (RR: 1.19, 1.06-1.34, p=0.03). A similar trend was apparent based on distance travelled but was of borderline statistical significance (RR: 1.11, 0.99-1.25, p=0.07). Collectively, it can be inferred from these findings that mandatory license re-testing schemes of the type evaluated have no demonstrable road safety benefits overall. Further research to resolve this on-going policy debate is discussed and recommended.

Analyzing fault in pedestrian-motor vehicle crashes in North Carolina.

PubMed

Ulfarsson, Gudmundur F; Kim, Sungyop; Booth, Kathleen M

2010-11-01

Crashes between pedestrians and motor vehicles are an important traffic safety concern. This paper explores the assignment of fault in such crashes, where observed factors are associated with pedestrian at fault, driver at fault, or both at fault. The analysis is based on police reported crash data for 1997 through 2000 in North Carolina, U.S.A. The results show that pedestrians are found at fault in 59% of the crashes, drivers in 32%, and both are found at fault in 9%. The results indicate drivers need to take greater notice of pedestrians when drivers are turning, merging, and backing up as these are some of the prime factors associated with the driver being found at fault in a crash. Pedestrians must apply greater caution when crossing streets, waiting to cross, and when walking along roads, as these are correlated with pedestrians being found at fault. The results suggest a need for campaigns focused on positively affecting pedestrian street-crossing behavior in combination with added jaywalking enforcement. The results also indicate that campaigns to increase the use of pedestrian visibility improvements at night can have a significant positive impact on traffic safety. Intoxication is a concern and the results show that it is not only driver intoxication that is affecting safety, but also pedestrian intoxication. The findings show in combination with other research in the field, that results from traffic safety studies are not necessarily transferable between distant geographic locations, and that location-specific safety research needs to take place. It is also important to further study the specific effects of the design of the pedestrian environment on safety, e.g. crosswalk spacing, signal timings, etc., which together may affect pedestrian safety and pedestrian behavior. 2010 Elsevier Ltd. All rights reserved.

Biomechanical and ergonomic assessment of urban transit operators.

PubMed

Albert, Wayne J; Everson, Donald; Rae, Michelle; Callaghan, Jack P; Croll, Jim; Kuruganti, Usha

2014-01-01

The prevalence of neck and low back musculoskeletal injuries in transit operators has been shown to be high; with work absences exceeding double the National average. There is a lack of biomechanical data generated from field researches to inform on musculoskeletal risk associated with transportation and driving occupations. Instead there has been a reliance on simulated driving and questionnaire-based research. This study was designed to examine the musculoskeletal and biomechanical stresses experienced by urban bus drivers. The main objective was to obtain a baseline understanding of sitting posture, muscle activiation and subjective ratings of stress during regular driving tasks. Fifteen urban city bus drivers were recruited for this study. Bus drivers drove the same 65-minute bus route once, at the same time of day, in the same preselected bus. Wireless surface electromyography monitored muscular activity of the drivers' neck, upper trapezius, and erector spinae and video analysis and seat pressure mapping was used to monitor changes in driving posture. A health and lifestyle questionnaire was administered to record specific neck and back pain experienced by drivers as well as to provide lifestyle habits. Drivers were found to exhibit non-neutral postures for less than 30% of the time while conducting routine tasks of turning and stopping for passenger loading and unloading. The neck posture was the greatest concern in terms of non-neutral posture and this was supported by the higher muscle activation to the neck musculature. There was significant posture adjustment made during the one-hour driving period with the adjustments increasing with driving time. Activities associated with bus driving appear to require the use of non-neutral postures an increase in muscle activation. Significant postural adjustments were needed over the one-hour observation period suggesting that the musculoskeletal demands may increase over a regular 12-hour shift.

Hazard perception skills of young drivers with Attention Deficit Hyperactivity Disorder (ADHD) can be improved with computer based driver training: An exploratory randomised controlled trial.

PubMed

Bruce, C R; Unsworth, C A; Dillon, M P; Tay, R; Falkmer, T; Bird, P; Carey, L M

2017-12-01

Young drivers with Attention Deficit Hyperactivity Disorder (ADHD) are at higher risk of road traffic injuries than their peers. Increased risk correlates with poor hazard perception skill. Few studies have investigated hazard perception training using computer technology with this group of drivers. *Determine the presence and magnitude of the between-group and within- subject change in hazard perception skills in young drivers with ADHD who receive Drive Smart training. *Determine whether training-facilitated change in hazard perception is maintained over time. This was a feasibility study, randomised control trial conducted in Australia. The design included a delayed treatment for the control group. Twenty-five drivers with a diagnosis of ADHD were randomised to the Immediate Intervention or Delayed Intervention group.The Immediate Intervention group received a training session using a computer application entitled Drive Smart. The Delayed Intervention group watched a documentary video initially (control condition), followed by the Drive Smart computer training session. The participant's hazard perception skill was measured using the Hazard Perception Test (HPT). After adjusting for baseline scores, there was a significant betweengroup difference in post-intervention HPT change scores in favour of the Immediate Intervention group. The magnitude of the effect was large. There was no significant within-group delayed intervention effect. A significant maintenance effect was found at 6-week follow-up for the Immediate Intervention group. The hazard perception skills of participants improved following training with large effect size and some maintenance of gain. A multimodal approach to training is indicated to facilitate maintenance. A full-scale trial is feasible. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reusable Launch Vehicle Tank/Intertank Sizing Trade Study

NASA Technical Reports Server (NTRS)

Dorsey, John T.; Myers, David E.; Martin, Carl J.

2000-01-01

A tank and intertank sizing tool that includes effects of major design drivers, and which allows parametric studies to be performed, has been developed and calibrated against independent representative results. Although additional design features, such as bulkheads and field joints, are not currently included in the process, the improved level of fidelity has allowed parametric studies to be performed which have resulted in understanding of key tank and intertank design drivers, design sensitivities, and definition of preferred design spaces. The sizing results demonstrated that there were many interactions between the configuration parameters of internal/external payload, vehicle fineness ratio (half body angle), fuel arrangement (LOX-forward/LOX-aft), number of tanks, and tank shape/arrangement (number of lobes).

Final report : model deployment of a regional, multi-modal 511 traveler information system

DOT National Transportation Integrated Search

1999-02-01

A survey was designed and conducted, to extend prior work discussed in the Driver Fatigue and Alertness Study literature review, by collecting additional data about commercial motor vehicle (CMV) drivers and their job characteristics. It also sought ...

A peer-to-peer traffic safety campaign program.

DOT National Transportation Integrated Search

2014-06-01

The purpose of this project was to implement a peer-to-peer drivers safety program designed for high school students. : This project builds upon an effective peer-to-peer outreach effort in Texas entitled Teens in the Driver Seat (TDS), the : nati...

Seat Belts: Are They the Best Solution to the Real Problem?

ERIC Educational Resources Information Center

Comeau, Lee F.

1985-01-01

More children are killed outside their school buses than inside. To solve this problem, we should improve bus design, provide driver training programs for all school bus drivers, utilize the latest safety devices available, and improve ridership safety curriculum. (MLF)

Evaluation of an updated version of the risk awareness and perception training program for young drivers.

DOT National Transportation Integrated Search

2017-03-01

Previous research suggests newly licensed teen drivers often fail to anticipate where unexpected hazards might materialize. One : training program designed to address these apparent deficiencies in knowledge and skills that has shown promise in previ...

Improving Night Time Driving Safety Using Vision-Based Classification Techniques.

PubMed

Chien, Jong-Chih; Chen, Yong-Sheng; Lee, Jiann-Der

2017-09-24

The risks involved in nighttime driving include drowsy drivers and dangerous vehicles. Prominent among the more dangerous vehicles around at night are the larger vehicles which are usually moving faster at night on a highway. In addition, the risk level of driving around larger vehicles rises significantly when the driver's attention becomes distracted, even for a short period of time. For the purpose of alerting the driver and elevating his or her safety, in this paper we propose two components for any modern vision-based Advanced Drivers Assistance System (ADAS). These two components work separately for the single purpose of alerting the driver in dangerous situations. The purpose of the first component is to ascertain that the driver would be in a sufficiently wakeful state to receive and process warnings; this is the driver drowsiness detection component. The driver drowsiness detection component uses infrared images of the driver to analyze his eyes' movements using a MSR plus a simple heuristic. This component issues alerts to the driver when the driver's eyes show distraction and are closed for a longer than usual duration. Experimental results show that this component can detect closed eyes with an accuracy of 94.26% on average, which is comparable to previous results using more sophisticated methods. The purpose of the second component is to alert the driver when the driver's vehicle is moving around larger vehicles at dusk or night time. The large vehicle detection component accepts images from a regular video driving recorder as input. A bi-level system of classifiers, which included a novel MSR-enhanced KAZE-base Bag-of-Features classifier, is proposed to avoid false negatives. In both components, we propose an improved version of the Multi-Scale Retinex (MSR) algorithm to augment the contrast of the input. Several experiments were performed to test the effects of the MSR and each classifier, and the results are presented in experimental results section of this paper.

Dead-blow hammer design applied to a calibration target mechanism to dampen excessive rebound

NASA Technical Reports Server (NTRS)

Lim, Brian Y.

1991-01-01

An existing rotary electromagnetic driver was specified to be used to deploy and restow a blackbody calibration target inside of a spacecraft infrared science instrument. However, this target was much more massive than any other previously inherited design applications. The target experienced unacceptable bounce when reaching its stops. Without any design modification, the momentum generated by the driver caused the target to bounce back to its starting position. Initially, elastomeric dampers were used between the driver and the target. However, this design could not prevent the bounce, and it compromised the positional accuracy of the calibration target. A design that successfully met all the requirements incorporated a sealed pocket 85 percent full of 0.75 mm diameter stainless steel balls in the back of the target to provide the effect of a dead-blow hammer. The energy dissipation resulting from the collision of balls in the pocket successfully dampened the excess momentum generated during the target deployment. The disastrous effects of new requirements on a design with a successful flight history, the modifications that were necessary to make the device work, and the tests performed to verify its functionality are described.

Manned spacecraft automation and robotics

NASA Technical Reports Server (NTRS)

Erickson, Jon D.

1987-01-01

The Space Station holds promise of being a showcase user and driver of advanced automation and robotics technology. The author addresses the advances in automation and robotics from the Space Shuttle - with its high-reliability redundancy management and fault tolerance design and its remote manipulator system - to the projected knowledge-based systems for monitoring, control, fault diagnosis, planning, and scheduling, and the telerobotic systems of the future Space Station.

Driver Support Functions under Resource-Limited Situations

NASA Astrophysics Data System (ADS)

Inagaki, Toshiyuki; Itoh, Makoto; Nagai, Yoshitomo

This paper reports results of an experiment with a driving simulator in order to answer the following question: What type of support should be given to an automobile driver when it is determined, via some monitoring method, that the driver's situation awareness may not be appropriate to a given traffic condition? This paper compares (a) warning type support in which an auditory warning is given to the driver to enhance situation awareness and (b) action type support in which an autonomous safety control is executed as a soft protection for avoiding an accident. Although the both types of driver support are effective, the former sometimes fail to assure safety, which suggests a limitation of the human locus of control assumption, while efficacy of the latter may be degraded by an incorrect human reasoning that can happen under uncertainty. This paper discusses viewpoints needed in the design of systems for supporting drivers in resource-limited situations in which information or time available for a driver is limited in a given traffic condition.

The behavioral economics of drunk driving.

PubMed

Sloan, Frank A; Eldred, Lindsey M; Xu, Yanzhi

2014-05-01

This study investigates whether drinker-drivers attributes are associated with imperfect rationality or irrationality. Using data from eight U.S. cities, we determine whether drinker-drivers differ from other drinkers in cognitive ability, ignorance of driving while intoxicated (DWI) laws, have higher rates of time preference, are time inconsistent, and lack self-control on other measures. We find that drinker-drivers are relatively knowledgeable about DWI laws and do not differ on two of three study measures of cognitive ability from other drinkers. Drinker-drivers are less prone to plan events involving drinking, e.g., selecting a designated driver in advance of drinking, and are more impulsive. Furthermore, we find evidence in support of hyperbolic discounting. In particular, relative to non-drinker-drivers, the difference between short- and long-term discount rates is much higher for drinker-drivers than for other drinkers. Implications of our findings for public policy, including incapacitation, treatment, and educational interventions, are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

Graduated Driver Licensing

PubMed Central

Bates, Lyndel J.; Allen, Siobhan; Armstrong, Kerry; Watson, Barry; King, Mark J.; Davey, Jeremy

2014-01-01

Graduated driver licensing (GDL) aims to gradually increase the exposure of new drivers to more complex driving situations and typically consists of learner, provisional and open licence phases. The first phase, the learner licence, is designed to allow novice drivers to obtain practical driving experience in lower risk situations. The learner licence can delay licensure, encourage novice drivers to learn under supervision, mandate the number of hours of practice required to progress to the next phase and encourage parental involvement. The second phase, the provisional licence, establishes various driving restrictions and thereby reduces exposure to situations of higher risk, such as driving at night, with passengers or after drinking alcohol. Parental involvement with a GDL system appears essential in helping novices obtain sufficient practice and in enforcing compliance with restrictions once the new driver obtains a provisional licence. Given the significant number of young drivers involved in crashes within Oman, GDL is one countermeasure that may be beneficial in reducing crash risk and involvement for this group. PMID:25364543

Obstructive sleep apnea among express bus drivers in Malaysia: important indicators for screening.

PubMed

Yusoff, M Fadhli Mohd; Baki, Marina Mat; Mohamed, Norlen; Mohamed, A Sani; Yunus, M Razif Mohamad; Ami, Mazita; Othman, Ilhamah; Ishak, Azlan I

2010-12-01

Obstructive sleep apnea (OSA) has been identified as one of the significant risk factors for motor vehicle crashes (MVCs). In the interest of public safety, this study was conducted to determine the prevalence of OSA and its associated factors among express bus drivers in Malaysia. Identifying factors or conditions related with OSA is very important because they can be used as indicators to subject a person to a confirmatory diagnosis using polysomnography testing. Two hundred eighty-nine randomly selected express bus drivers from 5 express bus companies participated in the study. Information on demography, medical history, clinical symptoms, and signs of OSA were collected by a designated medical officer and the diagnosis of OSA was done based on the Apnea Hypopnoea Index (AHI) from polysomnography testing. Based on AHI, 128 (44.3%) subjects were diagnosed as having OSA with 83 (28.7%), 26 (9.0%), and 26 (6.6%) classified as mild, moderate, and severe OSA, respectively. Multiple logistic regression analysis results showed that age (odds ratio [OR] = 1.05, 95% confidence interval [CI] 1.01-1.09), snoring (OR = 3.54, 95% CI 1.91-6.57), body mass index (BMI; OR = 1.17, 95% CI 1.09-1.25), hypertension (OR = 1.87, 95% CI 1.02-3.40), and neck circumference (OR = 1.31, 95% CI 1.18-1.46) were significantly associated with OSA status. The results supported the need for identifying the risk group for OSA among express bus drivers and the need to diagnose them early for an early intervention.

A Modular GIS-Based Software Architecture for Model Parameter Estimation using the Method of Anchored Distributions (MAD)

NASA Astrophysics Data System (ADS)

Ames, D. P.; Osorio-Murillo, C.; Over, M. W.; Rubin, Y.

2012-12-01

The Method of Anchored Distributions (MAD) is an inverse modeling technique that is well-suited for estimation of spatially varying parameter fields using limited observations and Bayesian methods. This presentation will discuss the design, development, and testing of a free software implementation of the MAD technique using the open source DotSpatial geographic information system (GIS) framework, R statistical software, and the MODFLOW groundwater model. This new tool, dubbed MAD-GIS, is built using a modular architecture that supports the integration of external analytical tools and models for key computational processes including a forward model (e.g. MODFLOW, HYDRUS) and geostatistical analysis (e.g. R, GSLIB). The GIS-based graphical user interface provides a relatively simple way for new users of the technique to prepare the spatial domain, to identify observation and anchor points, to perform the MAD analysis using a selected forward model, and to view results. MAD-GIS uses the Managed Extensibility Framework (MEF) provided by the Microsoft .NET programming platform to support integration of different modeling and analytical tools at run-time through a custom "driver." Each driver establishes a connection with external programs through a programming interface, which provides the elements for communicating with core MAD software. This presentation gives an example of adapting the MODFLOW to serve as the external forward model in MAD-GIS for inferring the distribution functions of key MODFLOW parameters. Additional drivers for other models are being developed and it is expected that the open source nature of the project will engender the development of additional model drivers by 3rd party scientists.

A New Conception of Bucket Wheel Excavator Cab and Seat Mounting

NASA Astrophysics Data System (ADS)

Blekta, J.; Mevald, J.; Petríková, I.; Petříček, J.; Lufinka, A.

One of the most important problem of coal mining by bucket wheel excavators is how to minimize influence of vibrations on driver's body. Project of Ministry of Trade and Industry of the Czech Republic solved in Technical University of Liberec was engaged in this problem. The aim of this project was to design a new cab and seat mounting of wheel excavator Schrs 1320. A suitable possibilities of cab suspensions were investigated to minimize driver body vibrations and to improve influence of mining process to drivers health. After optimization one concept was chosen. A new methodic of measured data evaluation was created for using in excavators as well as in laboratory. The new concept of dynamic seat absorber were designed also.

250 kA compact linear transformer driver for wire array z-pinch loads

NASA Astrophysics Data System (ADS)

Bott, S. C.; Haas, D. M.; Madden, R. E.; Ueda, U.; Eshaq, Y.; Collins, G., IV; Gunasekera, K.; Mariscal, D.; Peebles, J.; Beg, F. N.; Mazarakis, M.; Struve, K.; Sharpe, R.

2011-05-01

We present the application of a short rise (˜150ns) 250 kA linear transformer driver (LTD) to wire array z-pinch loads for the first time. The generator is a modification of a previous driver in which a new conical power feed provides a low inductance coupling to wire loads. Performance of the new design using both short circuit and plasma loads is presented and discussed. The final design delivers ˜200kA to a wire array load which is in good agreement with SCREAMER calculations using a simplified representative circuit. Example results demonstrate successful experiments using cylindrical, conical, and inverse wire arrays as well as previously published work on x-pinch loads.

The environmental control and life-support system for a lunar base: What drives its design

NASA Technical Reports Server (NTRS)

Hypes, Warren D.; Hall, John B., Jr.

1992-01-01

The purpose of this paper is to identify and briefly discuss some of the ground rules and mission scenario details that become drivers of the environmental control and life support (ECLS) system design and of the logistics related to the design. This paper is written for mission planners and non-ECLS system engineers to inform them of the details that will be important to the ECLS engineer when the design phase is reached. In addition, examples illustrate the impact of some selected mission characteristics on the logistics associated with ECLS systems. The last section of this paper focuses on the ECLS system technology development sequence and highlights specific portions that need emphasis.

Representative Agricultural Pathways: A Trans-Disciplinary Approach to Agricultural Model Inter-comparison, Improvement, Climate Impact Assessment and Stakeholder Engagement

NASA Astrophysics Data System (ADS)

Antle, J. M.; Valdivia, R. O.; Claessens, L.; Nelson, G. C.; Rosenzweig, C.; Ruane, A. C.; Vervoort, J.

2013-12-01

The global change research community has recognized that new pathway and scenario concepts are needed to implement impact and vulnerability assessment that is logically consistent across local, regional and global scales. For impact and vulnerability assessment, new socio-economic pathway and scenario concepts are being developed. Representative Agricultural Pathways (RAPs) are designed to extend global pathways to provide the detail needed for global and regional assessment of agricultural systems. In addition, research by the Agricultural Model Inter-comparison and Improvement Project (AgMIP) shows that RAPs provide a powerful way to engage stakeholders in climate-related research throughout the research process and in communication of research results. RAPs are based on the integrated assessment framework developed by AgMIP. This framework shows that both bio-physical and socio-economic drivers are essential components of agricultural pathways and logically precede the definition of adaptation and mitigation scenarios that embody associated capabilities and challenges. This approach is based on a trans-disciplinary process for designing pathways and then translating them into parameter sets for bio-physical and economic models that are components of agricultural integrated assessments of climate impact, adaptation and mitigation. RAPs must be designed to be part of a logically consistent set of drivers and outcomes from global to regional and local. Global RAPs are designed to be consistent with higher-level global socio-economic pathways, but add key agricultural drivers such as agricultural growth trends that are not specified in more general pathways, as illustrated in a recent inter-comparison of global agricultural models. To create pathways at regional or local scales, further detail is needed. At this level, teams of scientists and other experts with knowledge of the agricultural systems and regions work together through a step-wise process. Experiences from AgMIP Regional Teams, and from the project on Regional Approaches to Climate Change in the Pacific Northwest, are used to discuss how the RAPs procedures can be further developed and improved, and how RAPs can help engage stakeholders in climate-related research throughout the research process and in communication of research results.

Cell Phone Ring Suppression and HUD Caller ID: Effectiveness in Reducing Momentary Driver Distraction under Varying Workload Levels

NASA Astrophysics Data System (ADS)

Nowakowski, C.; Friedman, D.; Green, P.

2001-10-01

The purpose of the current experiment is to provide a preliminary driving simulator assessment of several hands-free design solutions with regard to the task of answering the phone while driving. Specifically, the following questions were examined: (1) Does the location of a caller ID display and the phone buttons (two HUD (Head Up Display) locations vs. phone cradle) affect either the time to answer the phone or driving performance; (2) Does the presence or absence of a ring affect either the time to answer the phone or driving performance; (3) Does increased driving workload (visual demand) affect either the time to answer the phone or driving performance; (4) What were the initial driver reactions to a HUD-based call timer.

Techniques for predicting high-risk drivers for alcohol countermeasures. Volume 2, User manual

DOT National Transportation Integrated Search

1978-06-01

This user manual, a companion to the Volume I Technical Report by the same name, is designed to aid the alcohol program administrator in his decisions concerning implementation of countermeasures to selected individuals or small groups of drivers. Vo...

Identifying compensatory driving behavior among older adults using the situational avoidance questionnaire.

PubMed

Davis, Jessica J; Conlon, Elizabeth G

2017-12-01

Driving self-regulation is considered a means through which older drivers can compensate for perceived declines in driving skill or more general feelings of discomfort on the road. One form of driving self-regulation is situational avoidance, the purposeful avoidance of situations perceived as challenging or potentially hazardous. This study aimed to validate the Situational Avoidance Questionnaire (SAQ, Davis, Conlon, Ownsworth, & Morrissey, 2016) and identify the point on the scale at which drivers practicing compensatory avoidance behavior could be distinguished from those whose driving is unrestricted, or who are avoiding situations for other, non-compensatory reasons (e.g., time or convenience). Seventy-nine Australian drivers (M age =71.48, SD=7.16, range: 55 to 86years) completed the SAQ and were classified as a compensatory-restricted or a non-restricted driver based on a semi-structured interview designed to assess the motivations underlying avoidance behavior reported on the SAQ. Using receiver-operator characteristic (ROC) analysis, the SAQ was found to have high diagnostic accuracy (sensitivity: 85%, specificity: 82%) in correctly classifying the driver groups. Group comparisons confirmed that compensatory-restricted drivers were self-regulating their driving behavior to reduce the perceived demands of the driving task. This group had, on average, slower hazard perception reaction times, and reported greater difficulty with driving, more discomfort when driving due to difficulty with hazard perception skills, and greater changes in cognition over the past five years. The SAQ is a psychometrically sound measure of situational avoidance for drivers in baby boomer and older adult generations. Use of validated measures of driving self-regulation that distinguish between compensatory and non-compensatory behavior, such as the SAQ, will advance our understanding of the driving self-regulation construct and its potential safety benefits for older road users. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

Real-time driver drowsiness feedback improves driver alertness and self-reported driving performance.

PubMed

Aidman, Eugene; Chadunow, Carolyn; Johnson, Kayla; Reece, John

2015-08-01

Driver drowsiness has been implicated as a major causal factor in road accidents. Tools that allow remote monitoring and management of driver fatigue are used in the mining and road transport industries. Increasing drivers' own awareness of their drowsiness levels using such tools may also reduce risk of accidents. The study examined the effects of real-time blink-velocity-derived drowsiness feedback on driver performance and levels of alertness in a military setting. A sample of 15 Army Reserve personnel (1 female) aged 21-59 (M=41.3, SD=11.1) volunteered to being monitored by an infra-red oculography-based Optalert Alertness Monitoring System (OAMS) while they performed their regular driving tasks, including on-duty tasks and commuting to and from duty, for a continuous period of 4-8 weeks. For approximately half that period, blink-velocity-derived Johns Drowsiness Scale (JDS) scores were fed back to the driver in a counterbalanced repeated-measures design, resulting in a total of 419 driving periods under "feedback" and 385 periods under "no-feedback" condition. Overall, the provision of real-time feedback resulted in reduced drowsiness (lower JDS scores) and improved alertness and driving performance ratings. The effect was small and varied across the 24-h circadian cycle but it remained robust after controlling for time of day and driving task duration. Both the number of JDS peaks counted for each trip and their duration declined in the presence of drowsiness feedback, indicating a dynamic pattern that is consistent with a genuine, entropy-reducing feedback mechanism (as distinct from random re-alerting) behind the observed effect. Its mechanisms and practical utility have yet to be fully explored. Direct examination of the alternative, random re-alerting explanation of this feedback effect is an important step for future research. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Examination of drivers' cell phone use behavior at intersections by using naturalistic driving data.

PubMed

Xiong, Huimin; Bao, Shan; Sayer, James; Kato, Kazuma

2015-09-01

Many driving simulator studies have shown that cell phone use while driving greatly degraded driving performance. In terms of safety analysis, many factors including drivers, vehicles, and driving situations need to be considered. Controlled or simulated studies cannot always account for the full effects of these factors, especially situational factors such as road condition, traffic density, and weather and lighting conditions. Naturalistic driving by its nature provides a natural and realistic way to examine drivers' behaviors and associated factors for cell phone use while driving. In this study, driving speed while using a cell phone (conversation or visual/manual tasks) was compared to two baselines (baseline 1: normal driving condition, which only excludes driving while using a cell phone, baseline 2: driving-only condition, which excludes all types of secondary tasks) when traversing an intersection. The outcomes showed that drivers drove slower when using a cell for both conversation and visual/manual (VM) tasks compared to baseline conditions. With regard to cell phone conversations, drivers were more likely to drive faster during the day time compared to night time driving and drive slower under moderate traffic compared to under sparse traffic situations. With regard to VM tasks, there was a significant interaction between traffic and cell phone use conditions. The maximum speed with VM tasks was significantly lower than that with baseline conditions under sparse traffic conditions. In contrast, the maximum speed with VM tasks was slightly higher than that with baseline driving under dense traffic situations. This suggests that drivers might self-regulate their behavior based on the driving situations and demand for secondary tasks, which could provide insights on driver distraction guidelines. With the rapid development of in-vehicle technology, the findings in this research could lead the improvement of human-machine interface (HMI) design as well. Copyright © 2015 Elsevier Ltd and National Safety Council. All rights reserved.

Numerical assessment of fore-and-aft suspension performance to reduce whole-body vibration of wheel loader drivers

NASA Astrophysics Data System (ADS)

Fleury, Gérard; Mistrot, Pierre

2006-12-01

While driving off-road vehicles, operators are exposed to whole-body vibration acting in the fore-and-aft direction. Seat manufacturers supply products equipped with fore-and-aft suspension but only a few studies report on their performance. This work proposes a computational approach to design fore-and-aft suspensions for wheel loader seats. Field tests were conducted in a quarry to analyse the nature of vibration to which the driver was exposed. Typical input signals were recorded to be reproduced in the laboratory. Technical specifications are defined for the suspension. In order to evaluate the suspension vibration attenuation performance, a model of a sitting human body was developed and coupled to a seat model. The seat model combines the models of each suspension component. A linear two-degree-of-freedom model is used to describe the dynamic behaviour of the sitting driver. Model parameters are identified by fitting the computed apparent mass frequency response functions to the measured values. Model extensions are proposed to investigate postural effects involving variations in hands and feet positions and interaction of the driver's back with the backrest. Suspension design parameters are firstly optimized by computing the seat/man model response to sinusoidal acceleration. Four criteria including transmissibility, interaction force between the driver's back and the backrest and relative maximal displacement of the suspension are computed. A new suspension design with optimized features is proposed. Its performance is checked from calculations of the response of the seat/man model subjected to acceleration measured on the wheel loader during real work conditions. On the basis of the computed values of the SEAT factors, it is found possible to design a suspension that would increase the attenuation provided by the seat by a factor of two.

Model for understanding consumer textural food choice

PubMed Central

Jeltema, Melissa; Beckley, Jacqueline; Vahalik, Jennifer

2015-01-01

The current paradigm for developing products that will match the marketing messaging is flawed because the drivers of product choice and satisfaction based on texture are misunderstood. Qualitative research across 10 years has led to the thesis explored in this research that individuals have a preferred way to manipulate food in their mouths (i.e., mouth behavior) and that this behavior is a major driver of food choice, satisfaction, and the desire to repurchase. Texture, which is currently thought to be a major driver of product choice, is a secondary factor, and is important only in that it supports the primary driver—mouth behavior. A model for mouth behavior is proposed and the qualitative research supporting the identification of different mouth behaviors is presented. The development of a trademarked typing tool for characterizing mouth behavior is described along with quantitative substantiation of the tool's ability to group individuals by mouth behavior. The use of these four groups to understand textural preferences and the implications for a variety of areas including product design and weight management are explored. PMID:25987995

Greater cerebellar gray matter volume in car drivers: an exploratory voxel-based morphometry study

PubMed Central

Sakai, Hiroyuki; Ando, Takafumi; Sadato, Norihiro; Uchiyama, Yuji

2017-01-01

Previous functional neuroimaging studies have identified multiple brain areas associated with distinct aspects of car driving in simulated traffic environments. Few studies, however, have examined brain morphology associated with everyday car-driving experience in real traffic. Thus, the aim of the current study was to identify gray matter volume differences between drivers and non-drivers. We collected T1-weighted structural brain images from 73 healthy young adults (36 drivers and 37 non-drivers). We performed a whole-brain voxel-based morphometry analysis to examine between-group differences in regional gray matter volume. Compared with non-drivers, drivers showed significantly greater gray matter volume in the left cerebellar hemisphere, which has been associated with cognitive rather than motor functioning. In contrast, we found no brain areas with significantly greater gray matter volume in non-drivers compared with drivers. Our findings indicate that experience with everyday car driving in real traffic is associated with greater gray matter volume in the left cerebellar hemisphere. This brain area may be involved in abilities that are critical for driving a car, but are not commonly or frequently used during other daily activities. PMID:28417971

Greater cerebellar gray matter volume in car drivers: an exploratory voxel-based morphometry study.

PubMed

Sakai, Hiroyuki; Ando, Takafumi; Sadato, Norihiro; Uchiyama, Yuji

2017-04-18

Previous functional neuroimaging studies have identified multiple brain areas associated with distinct aspects of car driving in simulated traffic environments. Few studies, however, have examined brain morphology associated with everyday car-driving experience in real traffic. Thus, the aim of the current study was to identify gray matter volume differences between drivers and non-drivers. We collected T1-weighted structural brain images from 73 healthy young adults (36 drivers and 37 non-drivers). We performed a whole-brain voxel-based morphometry analysis to examine between-group differences in regional gray matter volume. Compared with non-drivers, drivers showed significantly greater gray matter volume in the left cerebellar hemisphere, which has been associated with cognitive rather than motor functioning. In contrast, we found no brain areas with significantly greater gray matter volume in non-drivers compared with drivers. Our findings indicate that experience with everyday car driving in real traffic is associated with greater gray matter volume in the left cerebellar hemisphere. This brain area may be involved in abilities that are critical for driving a car, but are not commonly or frequently used during other daily activities.

Argonne simulation framework for intelligent transportation systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ewing, T.; Doss, E.; Hanebutte, U.

1996-04-01

A simulation framework has been developed which defines a high-level architecture for a large-scale, comprehensive, scalable simulation of an Intelligent Transportation System (ITS). The simulator is designed to run on parallel computers and distributed (networked) computer systems; however, a version for a stand alone workstation is also available. The ITS simulator includes an Expert Driver Model (EDM) of instrumented ``smart`` vehicles with in-vehicle navigation units. The EDM is capable of performing optimal route planning and communicating with Traffic Management Centers (TMC). A dynamic road map data base is sued for optimum route planning, where the data is updated periodically tomore » reflect any changes in road or weather conditions. The TMC has probe vehicle tracking capabilities (display position and attributes of instrumented vehicles), and can provide 2-way interaction with traffic to provide advisories and link times. Both the in-vehicle navigation module and the TMC feature detailed graphical user interfaces that includes human-factors studies to support safety and operational research. Realistic modeling of variations of the posted driving speed are based on human factor studies that take into consideration weather, road conditions, driver`s personality and behavior and vehicle type. The simulator has been developed on a distributed system of networked UNIX computers, but is designed to run on ANL`s IBM SP-X parallel computer system for large scale problems. A novel feature of the developed simulator is that vehicles will be represented by autonomous computer processes, each with a behavior model which performs independent route selection and reacts to external traffic events much like real vehicles. Vehicle processes interact with each other and with ITS components by exchanging messages. With this approach, one will be able to take advantage of emerging massively parallel processor (MPP) systems.« less

System study of a diode-pumped solid-state-laser driver for inertial fusion energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orth, C.D.; Payne, S.A.

The present a conceptual design of a diode-pumped solid-state-laser (DPSSL) driver for an inertial fusion energy (IFE) power plant based on the maximized cost of electricity (COE) as determined in a comprehensive systems study. This study contained extensive detail for all significant DPSSL physics and costs, plus published scaling relationships for the costs of the target chamber and the balance of plant (BOP). Our DPSSL design offers low development cost because it is modular, can be fully tested functionally at reduced scale, and is based on mature solid-state-laser technology. Most of the parameter values that we used are being verifiedmore » by experiments now in progress. Future experiments will address the few issues that remain. As a consequence, the economic and technical risk of our DPSSL driver concept is becoming rather low. Baseline performance at 1 GW{sub e} using a new gain medium [Yb{sup 3+}-doped Sr{sub 5}(PO{sub 4}){sub 3}F or Yb:S-FAP] includes a product of laser efficiency and target gain of {eta}G = 7, and a COE of 8.6 cents/kW{center_dot}h, although values of {eta}G {ge} 11 and COEs {le}6.6 cents/kW{center_dot}h are possible at double the assumed target gain of 76 at 3.7 MJ. We present a summary of our results, discuss why other more-common types of laser media do not perform as well as Yb:S-FAP, and present a simple model that shows where DPSSL development should proceed to reduce projected COEs.« less

Improved Propulsion Modeling for Low-Thrust Trajectory Optimization

NASA Technical Reports Server (NTRS)

Knittel, Jeremy M.; Englander, Jacob A.; Ozimek, Martin T.; Atchison, Justin A.; Gould, Julian J.

2017-01-01

Low-thrust trajectory design is tightly coupled with spacecraft systems design. In particular, the propulsion and power characteristics of a low-thrust spacecraft are major drivers in the design of the optimal trajectory. Accurate modeling of the power and propulsion behavior is essential for meaningful low-thrust trajectory optimization. In this work, we discuss new techniques to improve the accuracy of propulsion modeling in low-thrust trajectory optimization while maintaining the smooth derivatives that are necessary for a gradient-based optimizer. The resulting model is significantly more realistic than the industry standard and performs well inside an optimizer. A variety of deep-space trajectory examples are presented.

The effect of varying levels of vehicle automation on drivers' lane changing behaviour.

PubMed

Madigan, Ruth; Louw, Tyron; Merat, Natasha

2018-01-01

Much of the Human Factors research into vehicle automation has focused on driver responses to critical scenarios where a crash might occur. However, there is less knowledge about the effects of vehicle automation on drivers' behaviour during non-critical take-over situations, such as driver-initiated lane-changing or overtaking. The current driving simulator study, conducted as part of the EC-funded AdaptIVe project, addresses this issue. It uses a within-subjects design to compare drivers' lane-changing behaviour in conventional manual driving, partially automated driving (PAD) and conditionally automated driving (CAD). In PAD, drivers were required to re-take control from an automated driving system in order to overtake a slow moving vehicle, while in CAD, the driver used the indicator lever to initiate a system-performed overtaking manoeuvre. Results showed that while drivers' acceptance of both the PAD and CAD systems was high, they generally preferred CAD. A comparison of overtaking positions showed that drivers initiated overtaking manoeuvres slightly later in PAD than in manual driving or CAD. In addition, when compared to conventional driving, drivers had higher deviations in lane positioning and speed, along with higher lateral accelerations during lane changes following PAD. These results indicate that even in situations which are not time-critical, drivers' vehicle control after automation is degraded compared to conventional driving.

Exploring the relationship between alcohol and the driver characteristics in motor vehicle accidents.

PubMed

Abdel-Aty, M A; Abdelwahab, H T

2000-07-01

This study examines the differences in alcohol-related accident involvement among different driver groups in the state of Florida. The driver characteristics considered in this study are: age, gender, race, and residency of the driver of a motor vehicle involved in an accident while under the influence of alcohol, drugs, or alcohol and drugs. The main objective of this study is to test whether there are associations between the different driver characteristics and alcohol involvement in traffic accidents, and to identify the high-risk group within each driver factor. This would improve our understanding of the relationship between alcohol involvement, accidents, and the four aforementioned driver factors. It would also enable us to better design educational and awareness programs targeting specific groups in the population to reduce drinking and driving in the state. The relationship between alcohol-related accident involvement and the driver factors are investigated using general descriptive statistics, conditional probabilities and log-linear models. The results showed that the 25-34 age group experience the highest rate of alcohol/drug involvement in accidents. The rates decline with the increase in the age of the drivers. The results also indicated that there are significant relationships between the driver characteristics and alcohol/drug involvement in accidents. Male, white, and in-state drivers were also more involved in alcohol/drugs-related traffic accidents.

Influence of driver nationality on the risk of causing vehicle collisions in Spain

PubMed Central

Lardelli, C; Luna, D; Jimenez, M; Bueno, C; Garcia, M; Galvez, V

2002-01-01

Study objective: To estimate the association between driver nationality and the risk of causing a collision between vehicles in motion. Design: Retrospective, matched by collision, case-control study. Setting: Collisions that occurred in Spain during the period from 1990 to 1999 were studied. Participants: Responsible (case) and non-responsible (control) drivers identified in the databases of the Dirección General de Tráfico (General Traffic Directorate) who were involved in a collisions between two or more four wheeled vehicles in motion, in which only one of the drivers had committed a traffic violation. Main results: Crude odds ratios (ORs) for the effect of driver nationality on the risk of causing a collision were significantly higher for foreign drivers than for Spanish drivers, and ranged from a minimum of 1.19 (95% CI 1.09 to 1.29) for Portuguese drivers to a maximum of 2.06 (1.88 to 2.27) for British drivers. Corresponding adjusted ORs were slightly lower, but were still significantly higher than 1 for all nationalities except Italian, Belgian, and American (USA). Adjusted ORs were usually higher for collisions that occurred in urban areas than on open roads. Conclusions: Authorities responsible for traffic safety, and drivers in general, should consider foreign drivers in Spain at particularly high risk for causing collisions, especially in urban areas. PMID:11964439

Fusion of Optimized Indicators from Advanced Driver Assistance Systems (ADAS) for Driver Drowsiness Detection

PubMed Central

Daza, Iván G.; Bergasa, Luis M.; Bronte, Sebastián; Yebes, J. Javier; Almazán, Javier; Arroyo, Roberto

2014-01-01

This paper presents a non-intrusive approach for monitoring driver drowsiness using the fusion of several optimized indicators based on driver physical and driving performance measures, obtained from ADAS (Advanced Driver Assistant Systems) in simulated conditions. The paper is focused on real-time drowsiness detection technology rather than on long-term sleep/awake regulation prediction technology. We have developed our own vision system in order to obtain robust and optimized driver indicators able to be used in simulators and future real environments. These indicators are principally based on driver physical and driving performance skills. The fusion of several indicators, proposed in the literature, is evaluated using a neural network and a stochastic optimization method to obtain the best combination. We propose a new method for ground-truth generation based on a supervised Karolinska Sleepiness Scale (KSS). An extensive evaluation of indicators, derived from trials over a third generation simulator with several test subjects during different driving sessions, was performed. The main conclusions about the performance of single indicators and the best combinations of them are included, as well as the future works derived from this study. PMID:24412904

Taking Over Control From Highly Automated Vehicles in Complex Traffic Situations: The Role of Traffic Density.

PubMed

Gold, Christian; Körber, Moritz; Lechner, David; Bengler, Klaus

2016-06-01

The aim of this study was to quantify the impact of traffic density and verbal tasks on takeover performance in highly automated driving. In highly automated vehicles, the driver has to occasionally take over vehicle control when approaching system limits. To ensure safety, the ability of the driver to regain control of the driving task under various driving situations and different driver states needs to be quantified. Seventy-two participants experienced takeover situations requiring an evasive maneuver on a three-lane highway with varying traffic density (zero, 10, and 20 vehicles per kilometer). In a between-subjects design, half of the participants were engaged in a verbal 20-Questions Task, representing speaking on the phone while driving in a highly automated vehicle. The presence of traffic in takeover situations led to longer takeover times and worse takeover quality in the form of shorter time to collision and more collisions. The 20-Questions Task did not influence takeover time but seemed to have minor effects on the takeover quality. For the design and evaluation of human-machine interaction in takeover situations of highly automated vehicles, the traffic state seems to play a major role, compared to the driver state, manipulated by the 20-Questions Task. The present results can be used by developers of highly automated systems to appropriately design human-machine interfaces and to assess the driver's time budget for regaining control. © 2016, Human Factors and Ergonomics Society.

Key Reliability Drivers of Liquid Propulsion Engines and A Reliability Model for Sensitivity Analysis

NASA Technical Reports Server (NTRS)

Huang, Zhao-Feng; Fint, Jeffry A.; Kuck, Frederick M.

2005-01-01

This paper is to address the in-flight reliability of a liquid propulsion engine system for a launch vehicle. We first establish a comprehensive list of system and sub-system reliability drivers for any liquid propulsion engine system. We then build a reliability model to parametrically analyze the impact of some reliability parameters. We present sensitivity analysis results for a selected subset of the key reliability drivers using the model. Reliability drivers identified include: number of engines for the liquid propulsion stage, single engine total reliability, engine operation duration, engine thrust size, reusability, engine de-rating or up-rating, engine-out design (including engine-out switching reliability, catastrophic fraction, preventable failure fraction, unnecessary shutdown fraction), propellant specific hazards, engine start and cutoff transient hazards, engine combustion cycles, vehicle and engine interface and interaction hazards, engine health management system, engine modification, engine ground start hold down with launch commit criteria, engine altitude start (1 in. start), Multiple altitude restart (less than 1 restart), component, subsystem and system design, manufacturing/ground operation support/pre and post flight check outs and inspection, extensiveness of the development program. We present some sensitivity analysis results for the following subset of the drivers: number of engines for the propulsion stage, single engine total reliability, engine operation duration, engine de-rating or up-rating requirements, engine-out design, catastrophic fraction, preventable failure fraction, unnecessary shutdown fraction, and engine health management system implementation (basic redlines and more advanced health management systems).

Object-based selection in the Baylis and Driver (1993) paradigm is subject to space-based attentional modulation.

PubMed

Müller, Hermann J; O'Grady, Rebecca; Krummenacher, Joseph; Heller, Dieter

2008-11-01

Three experiments re-examined Baylis and Driver's (1993) strong evidence for object-based selection, that making relative apex location judgments is harder between two objects than within a single object, with object (figure-ground) segmentation determined solely by color-based perceptual set. Using variations of the Baylis and Driver paradigm, the experiments replicated a two-object cost. However, they also showed a large part of the two-object cost to be attributable to space-based factors, though there remained an irreducible cost consistent with 'true' object-based selection.

Drivers and Barriers to Acceptance of Web-Based Aftercare of Patients in Inpatient Routine Care: A Cross-Sectional Survey

PubMed Central

Hennemann, Severin; Beutel, Manfred E

2016-01-01

Background Web-based aftercare can help to stabilize treatment effects and support transition after inpatient treatment, yet uptake by patients seems limited in routine care and little is known about the mechanisms of adoption and implementation. Objective The aim of this study was to (1) determine acceptance of Web-based aftercare and (2) explore its drivers and barriers in different subgroups of a mixed inpatient sample. Method In a cross-sectional design, 38.3% (374/977) of the inpatients from a broad spectrum of diagnostic groups (psychosomatic, cardiologic, orthopedic, pediatric, and substance-related disorders) filled out a self-administered questionnaire prior to discharge. Drivers and barriers to patients’ acceptance of Web-based aftercare were examined based on an extension to the “unified theory of acceptance and use of technology” (UTAUT). In total, 16.7% (59/353) of the participants indicated prior use of eHealth interventions. Results Acceptance (min 1, max 5) was low (mean 2.56, SD 1.22) and differed between diagnostic groups (Welch F4,133.10 =7.77, P<.001), with highest acceptance in adolescent patients (mean 3.46, SD 1.42). Acceptance was significantly predicted by 3 UTAUT predictors: social influence (beta=.39, P<.001), performance expectancy (beta=.31, P<.001), and effort expectancy (beta=.22, P<.001). Furthermore, stress due to permanent availability (beta=−.09, P=.01) was negatively associated with acceptance. Conclusion This study demonstrated a limited acceptance of Web-based aftercare in inpatients. Expectations, social environment’s attitude, and negative experience with permanent availability influence eHealth acceptance. Improving implementation, therefore, means increasing eHealth experience and literacy and facilitating positive attitudes in patients and health professionals through education and reduction of misconceptions about effectiveness or usability. PMID:28011445

Stimulus driver for epilepsy seizure suppression with adaptive loading impedance

NASA Astrophysics Data System (ADS)

Ker, Ming-Dou; Lin, Chun-Yu; Chen, Wei-Ling

2011-10-01

A stimulus driver circuit for a micro-stimulator used in an implantable device is presented in this paper. For epileptic seizure control, the target of the driver was to output 30 µA stimulus currents when the electrode impedance varied between 20 and 200 kΩ. The driver, which consisted of the output stage, control block and adaptor, was integrated in a single chip. The averaged power consumption of the stimulus driver was 0.24-0.56 mW at 800 Hz stimulation rate. Fabricated in a 0.35 µm 3.3 V/24 V CMOS process and applied to a closed-loop epileptic seizure monitoring and controlling system, the proposed design has been successfully verified in the experimental results of Long-Evans rats with epileptic seizures.

Coming back into the loop: Drivers' perceptual-motor performance in critical events after automated driving.

PubMed

Louw, Tyron; Markkula, Gustav; Boer, Erwin; Madigan, Ruth; Carsten, Oliver; Merat, Natasha

2017-11-01

This driving simulator study, conducted as part of the EU AdaptIVe project, investigated drivers' performance in critical traffic events, during the resumption of control from an automated driving system. Prior to the critical events, using a between-participant design, 75 drivers were exposed to various screen manipulations that varied the amount of available visual information from the road environment and automation state, which aimed to take them progressively further 'out-of-the-loop' (OoTL). The current paper presents an analysis of the timing, type, and rate of drivers' collision avoidance response, also investigating how these were influenced by the criticality of the unfolding situation. Results showed that the amount of visual information available to drivers during automation impacted on how quickly they resumed manual control, with less information associated with slower take-over times, however, this did not influence the timing of when drivers began a collision avoidance manoeuvre. Instead, the observed behaviour is in line with recent accounts emphasising the role of scenario kinematics in the timing of driver avoidance response. When considering collision incidents in particular, avoidance manoeuvres were initiated when the situation criticality exceeded an Inverse Time To Collision value of ≈0.3s -1 . Our results suggest that take-over time and timing and quality of avoidance response appear to be largely independent, and while long take-over time did not predict collision outcome, kinematically late initiation of avoidance did. Hence, system design should focus on achieving kinematically early avoidance initiation, rather than short take-over times. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fatigue and voluntary utilization of automation in simulated driving.

PubMed

Neubauer, Catherine; Matthews, Gerald; Langheim, Lisa; Saxby, Dyani

2012-10-01

A driving simulator was used to assess the impact on fatigue, stress, and workload of full vehicle automation that was initiated by the driver. Previous studies have shown that mandatory use of full automation induces a state of "passive fatigue" associated with loss of alertness. By contrast, voluntary use of automation may enhance the driver's perceptions of control and ability to manage fatigue. Participants were assigned to one of two experimental conditions, automation optional (AO) and nonautomation (NA), and then performed a 35 min, monotonous simulated drive. In the last 5 min, automation was unavailable and drivers were required to respond to an emergency event. Subjective state and workload were evaluated before and after the drive. Making automation available to the driver failed to alleviate fatigue and stress states induced by driving in monotonous conditions. Drivers who were fatigued prior to the drive were more likely to choose to use automation, but automation use increased distress, especially in fatigue-prone drivers. Drivers in the AO condition were slower to initiate steering responses to the emergency event, suggesting optional automation may be distracting. Optional, driver-controlled automation appears to pose the same dangers to task engagement and alertness as externally initiated automation. Drivers of automated vehicles may be vulnerable to fatigue that persists when normal vehicle control is restored. It is important to evaluate automated systems' impact on driver fatigue, to seek design solutions to the issue of maintaining driver engagement, and to address the vulnerabilities of fatigue-prone drivers.

Naturalistic distraction and driving safety in older drivers

PubMed Central

Aksan, Nazan; Dawson, Jeffrey D.; Emerson, Jamie L.; Yu, Lixi; Uc, Ergun Y.; Anderson, Steven W.; Rizzo, Matthew

2013-01-01

Objective This study aimed to quantify and compare performance of middle-aged and older drivers during a naturalistic distraction paradigm (visual search for roadside targets) and predict older driver performance given functioning in visual, motor, and cognitive domains. Background Distracted driving can imperil healthy adults and may disproportionally affect the safety of older drivers with visual, motor, and cognitive decline. Methods Two hundred and three drivers, 120 healthy older (61 men and 59 women, ages 65 years or greater) and 83 middle-aged drivers (38 men and 45 women, ages 40–64 years), participated in an on-road test in an instrumented vehicle. Outcome measures included performance in roadside target identification (traffic signs and restaurants) and concurrent driver safety. Differences in visual, motor, and cognitive functioning served as predictors. Results Older drivers identified fewer landmarks and drove slower but committed more safety errors than middle-aged drivers. Greater familiarity with local roads benefited performance of middle-aged but not older drivers. Visual cognition predicted both traffic sign identification and safety errors while executive function predicted traffic sign identification over and above vision. Conclusion Older adults are susceptible to driving safety errors while distracted by common secondary visual search tasks that are inherent to driving. The findings underscore that age-related cognitive decline affects older driver management of driving tasks at multiple levels, and can help inform the design of on-road tests and interventions for older drivers. PMID:23964422

Wisconsin Bicycle Driver Training Course. Instructor's Handbook.

ERIC Educational Resources Information Center

Thompson, Ronald L.

Designed for use by trained and certified instructors of a voluntary bicycle driver training course, this handbook provides materials for eight one-hour sessions for beginners or experienced bicyclists. Part 1, Instructor's Guidelines, discusses course objectives, organization, and content; instruction methods; and audiovisual materials. Part 2…

Driver Education Curriculum Guide.

ERIC Educational Resources Information Center

Brum, Herbert D.; And Others

Intended for driver education instructors in Ohio, the guide is designed to acquaint teachers with special characteristics, capacities, and needs of the handicapped student population and to provide resources, information, and ideas for meeting those special needs. An introductory section discusses the purpose and use of the curriculum. Section 2…

An analysis of crash likelihood : age versus driving experience

DOT National Transportation Integrated Search

1995-05-01

The study was designed to determine the crash likelihood of drivers in Michigan as a function of two independent variables: driver age and driving experience. The age variable had eight levels (18, 19, 20, 21, 22, 23, 24, and 25 years old) and the ex...

45 CFR 1310.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... Allowable Alternate Vehicle means a vehicle designed for carrying eleven or more people, including the driver, that meets all the Federal Motor Vehicle Safety Standards applicable to school buses, except 49... driver in ensuring the safety of the children while they ride, board, or exit the vehicle and for...

45 CFR 1310.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... Allowable Alternate Vehicle means a vehicle designed for carrying eleven or more people, including the driver, that meets all the Federal Motor Vehicle Safety Standards applicable to school buses, except 49... driver in ensuring the safety of the children while they ride, board, or exit the vehicle and for...

45 CFR 1310.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... Allowable Alternate Vehicle means a vehicle designed for carrying eleven or more people, including the driver, that meets all the Federal Motor Vehicle Safety Standards applicable to school buses, except 49... driver in ensuring the safety of the children while they ride, board, or exit the vehicle and for...

Effect of audio in-vehicle red light-running warning message on driving behavior based on a driving simulator experiment.

PubMed

Yan, Xuedong; Liu, Yang; Xu, Yongcun

2015-01-01

Drivers' incorrect decisions of crossing signalized intersections at the onset of the yellow change may lead to red light running (RLR), and RLR crashes result in substantial numbers of severe injuries and property damage. In recent years, some Intelligent Transport System (ITS) concepts have focused on reducing RLR by alerting drivers that they are about to violate the signal. The objective of this study is to conduct an experimental investigation on the effectiveness of the red light violation warning system using a voice message. In this study, the prototype concept of the RLR audio warning system was modeled and tested in a high-fidelity driving simulator. According to the concept, when a vehicle is approaching an intersection at the onset of yellow and the time to the intersection is longer than the yellow interval, the in-vehicle warning system can activate the following audio message "The red light is impending. Please decelerate!" The intent of the warning design is to encourage drivers who cannot clear an intersection during the yellow change interval to stop at the intersection. The experimental results showed that the warning message could decrease red light running violations by 84.3 percent. Based on the logistic regression analyses, drivers without a warning were about 86 times more likely to make go decisions at the onset of yellow and about 15 times more likely to run red lights than those with a warning. Additionally, it was found that the audio warning message could significantly reduce RLR severity because the RLR drivers' red-entry times without a warning were longer than those with a warning. This driving simulator study showed a promising effect of the audio in-vehicle warning message on reducing RLR violations and crashes. It is worthwhile to further develop the proposed technology in field applications.

Pedestrian Safety in Road Traffic in Poland

NASA Astrophysics Data System (ADS)

Budzynski, Marcin; Jamroz, Kazimierz; Mackun, Tomasz

2017-10-01

Every third road accident in Poland involves a pedestrian as a participant or, most of the time, a casualty. Pedestrian accidents are usually the result of complex situations and the outcome of a number of factors related to driver and pedestrian behaviour and road infrastructure. Safety depends largely on how well the traffic condition is perceived and on visibility in traffic. The paper presents the results of analyses of methodologies for systematic studies of pedestrian behaviour and pedestrian-driver relations. The effects of the location of the site, type of cross-section and other selected parameters on pedestrian and driver behaviour are demonstrated. The analyses showed that pedestrians are most often put at risk by too long pedestrian crossings, vehicles going too fast around pedestrian crossings, lack of proper sight distance and poorly lit or unlit pedestrian crossings. The reason for such defective infrastructure is that planners, designers, contractors and maintenance services are not receiving any support from design, marking and maintenance regulations for pedestrian traffic. In addition, the Road Traffic Law is not restrictive enough when it comes to drivers’ obligations towards pedestrian safety. Polish design regulations allow long pedestrian crossings up to four lanes in one direction or three lanes in two directions irrespective of traffic control and speed limits. Pedestrian crossings should be kept at a maximum of three lanes. There is nothing in the design regulations about the required driver-pedestrian sight distance. Neither does the Road Traffic Law help engineers with that. It is legal to park vehicles within 10 m of a pedestrian crossing which does not guarantee the necessary sight distance. Drivers must be able to see a pedestrian waiting or stepping onto the crossing from a distance that will help them come to a stop safely. It is safer to follow the principle of providing adequate pedestrian sight distance. Recommendations for pedestrian crossing design are also provided.

Let's party tonight: drinking patterns and breath alcohol values at high school parties.

PubMed

Schwartz, R H; Little, D L

1997-05-01

This study sought to determine whether the number of alcohol-containing beverages consumed by adolescents attending a "typical" high school weekend party was planned or spontaneous. A second objective was to understand the role of the designated driver and whether he or she honored a pledge of sobriety. A printed, anonymous survey with signed informed consent was distributed to 52 high school students from three different suburban high schools during three weekend high school parties. In addition, subjects underwent breath alcohol testing using the Intoximeter breath alcohol instrument. Salivary alcohol measurements were also obtained using Alco-Screen. Levels were measured in volunteers on entry and exit from the party. Fifty-two students volunteered to participate in the survey. Eleven participants volunteered to be designated drivers, nine of whom did not drink alcohol at this party. By the end of each party, the 26 boys had consumed a mean of 10 drinks, and the 16 girls had consumed 4.1 drinks, almost exactly what they had predicted at the time of arrival. By departure time, 22 (54%) of the drinkers had a breath alcohol value of .10 g/dL or greater, while only three (7%), had alcohol values of .02 g/dL or less. Blackouts were common and had been experienced by 73% of all the students surveyed. Twenty-seven percent of those surveyed had been involved in some form of physical violence while drinking. Eleven percent of the female participants reported being sexually assaulted while they or their attacker were drunk. Most of the 42 drinkers believed that it was acceptable for designated drivers to drink at least two beers. Two intoxicated designated drivers were driven home by sober friends. High school students in this study knew before attending a party the quantity of beer they would consume. Survey participants believed that it is acceptable practice for designated drivers to drink alcohol at parties; 13% of those who intended to drive after these parties were intoxicated.

EEG-based driver fatigue detection using hybrid deep generic model.

PubMed

Phyo Phyo San; Sai Ho Ling; Rifai Chai; Tran, Yvonne; Craig, Ashley; Hung Nguyen

2016-08-01

Classification of electroencephalography (EEG)-based application is one of the important process for biomedical engineering. Driver fatigue is a major case of traffic accidents worldwide and considered as a significant problem in recent decades. In this paper, a hybrid deep generic model (DGM)-based support vector machine is proposed for accurate detection of driver fatigue. Traditionally, a probabilistic DGM with deep architecture is quite good at learning invariant features, but it is not always optimal for classification due to its trainable parameters are in the middle layer. Alternatively, Support Vector Machine (SVM) itself is unable to learn complicated invariance, but produces good decision surface when applied to well-behaved features. Consolidating unsupervised high-level feature extraction techniques, DGM and SVM classification makes the integrated framework stronger and enhance mutually in feature extraction and classification. The experimental results showed that the proposed DBN-based driver fatigue monitoring system achieves better testing accuracy of 73.29 % with 91.10 % sensitivity and 55.48 % specificity. In short, the proposed hybrid DGM-based SVM is an effective method for the detection of driver fatigue in EEG.

A Manual Control Test for the Detection and Deterrence of Impaired Drivers

NASA Technical Reports Server (NTRS)

Stein, A. C.; Allen, R. W.; Jex, H. R.

1984-01-01

A brief manual control test and a decision strategy were developed, laboratory tested, and field validated which provide a means for detecting human operator impairment from alcohol or other drugs. The test requires the operator to stabilize progressively unstable controlled element dynamics. Control theory and experimental data verify that the human operator's control ability on this task is constrained by basic cybernetic characteristics, and that task performance is reliably affected by impairment effects on these characteristics. Assessment of human operator control ability is determined by a statistically based decision strategy. The operator is allowed several chances to exceed a preset pass criterion. Procedures are described for setting the pass criterion based on individual ability and a desired unimpaired failure rate. These procedures were field tested with apparatus installed in automobiles that were designed to discourage drunk drivers from operating their vehicles. This test program demonstrated that the control task and detection strategy could be applied in a practical setting to screen human operators for impairment in their basic cybernetic skills.

Design of integrated eye tracker-display device for head mounted systems

NASA Astrophysics Data System (ADS)

David, Y.; Apter, B.; Thirer, N.; Baal-Zedaka, I.; Efron, U.

2009-08-01

We propose an Eye Tracker/Display system, based on a novel, dual function device termed ETD, which allows sharing the optical paths of the Eye tracker and the display and on-chip processing. The proposed ETD design is based on a CMOS chip combining a Liquid-Crystal-on-Silicon (LCoS) micro-display technology with near infrared (NIR) Active Pixel Sensor imager. The ET operation allows capturing the Near IR (NIR) light, back-reflected from the eye's retina. The retinal image is then used for the detection of the current direction of eye's gaze. The design of the eye tracking imager is based on the "deep p-well" pixel technology, providing low crosstalk while shielding the active pixel circuitry, which serves the imaging and the display drivers, from the photo charges generated in the substrate. The use of the ETD in the HMD Design enables a very compact design suitable for Smart Goggle applications. A preliminary optical, electronic and digital design of the goggle and its associated ETD chip and digital control, are presented.

FleCSPH notes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lim, Hyun; Loiseau, Julien

FleCSI is a compile-time con gurable framework designed to support multi-physics application development. As such, FleCSI provides a very general set of infrastructure design patterns that can be specialized and extended to suit the needs of a broad variety of solver and data requirements. FleCSI currently supports multi-dimensional mesh topology, geometry, and adjacency information, as well as n-dimensional hashed-tree data structures, graph partitioning interfaces, and dependency closures. FleCSI introduces a functional programming model with control, execution, and data abstractions that are consistent both with MPI and with state-of-the-art, task-based runtimes such as Legion and Charm++. The abstraction layer insulates developersmore » from the underlying runtime, while allowing support for multiple runtime systems including conventional models like asynchronous MPI. The intent is to provide developers with a concrete set of user-friendly programming tools that can be used now, while allowing exibility in choosing runtime implementations and optimization that can be applied to future architectures and runtimes. FleCSI's control and execution models provide formal nomenclature for describing poorly understood concepts such as kernels and tasks. FleCSI's data model provides a low-buy-in approach that makes it an attractive option for many application projects, as developers are not locked into particular layouts or data structure representations. FleCSI currently provides a parallel but not distributed implementation of Binary, Quad and Oct-tree topology. This implementation is base on space lling curves domain decomposition, the Morton order. The current FleCSI version requires the implementation of a driver and a specialization driver. The role of the specialization driver is to provide the data distribution. This feature is not complete in FleCSI code and we provide it. The next step will be to incorporate it directly from FleCSPH to FleCSI as we reach a good level of performance. Then the driver represent the general execution of the resolution without worrying of the data locality and communications. As FleCSI is an On-Development code the structure may change in the future and we keep track of these changes in FleCSPH.« less

Building Sustainable Professional Development Programs: Applying Strategies From Implementation Science to Translate Evidence Into Practice.

PubMed

Baldwin, Constance D; Chandran, Latha; Gusic, Maryellen E

2017-01-01

Multisite and national professional development (PD) programs for educators are challenging to establish. Use of implementation science (IS) frameworks designed to convert evidence-based intervention methods into effective health care practice may help PD developers translate proven educational methods and models into successful, well-run programs. Implementation of the national Educational Scholars Program (ESP) is used to illustrate the value of the IS model. Four adaptable elements of IS are described: (1) replication of an evidence-based model, (2) systematic stages of implementation, (3) management of implementation using three implementation drivers, and (4) demonstration of program success through measures of fidelity to proven models and sustainability. Implementation of the ESP was grounded on five established principles and methods for successful PD. The process was conducted in four IS stages over 10 years: Exploration, Installation, Initial Implementation, and Full Implementation. To ensure effective and efficient processes, attention to IS implementation drivers helped to manage organizational relationships, build competence in faculty and scholars, and address leadership challenges. We describe the ESP's fidelity to evidence-based structures and methods, and offer three examples of sustainability efforts that enabled achievement of targeted program outcomes, including academic productivity, strong networking, and career advancement of scholars. Application of IS frameworks to program implementation may help other PD programs to translate evidence-based methods into interventions with enhanced impact. A PD program can follow systematic developmental stages and be operationalized by practical implementation drivers, thereby creating successful and sustainable interventions that promote the academic vitality of health professions educators.

Electronics drivers for high voltage dielectric electro active polymer (DEAP) applications

NASA Astrophysics Data System (ADS)

Zhang, Zhe; Andersen, Michael A. E.

2015-04-01

Dielectric electro active polymer (DEAP) can be used in actuation, sensing and energy harvesting applications, but driving the DEAP based actuators and generators has three main challenges from a power electronics standpoint, i.e. high voltage (around 2.5 kV), nonlinearity, and capacitive behavior. In this paper, electronics divers for heating valves, loud speakers, incremental motors, and energy harvesting are reviewed, studied and developed in accordance with their corresponding specifications. Due to the simplicity and low power capacity (below 10W), the reversible Fly-back converters with both magnetic and piezoelectric transformers are employed for the heating valve and incremental motor application, where only ON/OFF regulation is adopted for energy saving; as for DEAP based energy harvesting, the noisolated Buck/Boost converter is used, due to the system high power capacity (above 100W), but the voltage balancing across the series-connected high voltage IGBTs is a critical issue and accordingly a novel gate driver circuitry is proposed and equipped; due to the requirements of the audio products, such as low distortion and noise, the multi-level Buck converter based Class-D amplifier, because of its high control linearity, is implemented for the loud speaker applications. A synthesis among those converter topologies and control techniques is given; therefore, for those DEAP based applications, their diversity and similarity of electronics drivers, as well as the key technologies employed are analyzed. Therefore a whole picture of how to choose the proper topologies can be revealed. Finally, the design guidelines in order to achieve high efficiency and reliability are discussed.

Safe Driving Knowledge Dissemination and Testing Techniques. Volume III: Handbook. Final Report.

ERIC Educational Resources Information Center

McKnight, James; Green, Molly A.

Guidelines are presented for use by driver licensing agencies in the development of driver manuals, tests, and other means of disseminating information and testing license applicants. An introductory chapter discusses the purposes of written license tests and of drivers' manuals, focusing on the needs of groups of drivers based on kind of vehicle,…

A Novel GMM-Based Behavioral Modeling Approach for Smartwatch-Based Driver Authentication.

PubMed

Yang, Ching-Han; Chang, Chin-Chun; Liang, Deron

2018-03-28

All drivers have their own distinct driving habits, and usually hold and operate the steering wheel differently in different driving scenarios. In this study, we proposed a novel Gaussian mixture model (GMM)-based method that can improve the traditional GMM in modeling driving behavior. This new method can be applied to build a better driver authentication system based on the accelerometer and orientation sensor of a smartwatch. To demonstrate the feasibility of the proposed method, we created an experimental system that analyzes driving behavior using the built-in sensors of a smartwatch. The experimental results for driver authentication-an equal error rate (EER) of 4.62% in the simulated environment and an EER of 7.86% in the real-traffic environment-confirm the feasibility of this approach.

Design and cost drivers in 2-D braiding

NASA Technical Reports Server (NTRS)

Morales, Alberto

1993-01-01

Fundamentally, the braiding process is a highly efficient, low cost method for combining single yarns into circumferential shapes, as evidenced by the number of applications for continuous sleeving. However, this braiding approach cannot fully demonstrate that it can drastically reduce the cost of complex shape structural preforms. Factors such as part geometry, machine design and configuration, materials used, and operating parameters are described as key cost drivers and what is needed to minimize their effect on elevating the cost of structural braided preforms.

Latent class analysis of accident risks in usage-based insurance: Evidence from Beijing.

PubMed

Jin, Wen; Deng, Yinglu; Jiang, Hai; Xie, Qianyan; Shen, Wei; Han, Weijian

2018-06-01

Car insurance is quickly becoming a big data industry, with usage-based insurance (UBI) poised to potentially change the business of insurance. Telematics data, which are transmitted from wireless devices in car, are widely used in UBI to obtain individual-level travel and driving characteristics. While most existing studies have introduced telematics data into car insurance pricing, the telematics-related characteristics are directly obtained from the raw data. In this study, we propose to quantify drivers' familiarity with their driving routes and develop models to quantify drivers' accident risks using the telematics data. In addition, we build a latent class model to study the heterogeneity in travel and driving styles based on the telematics data, which has not been investigated in literature. Our main results include: (1) the improvement to the model fit is statistically significant by adding telematics-related characteristics; (2) drivers' familiarity with their driving trips is critical to identify high risk drivers, and the relationship between drivers' familiarity and accident risks is non-linear; (3) the drivers can be classified into two classes, where the first class is the low risk class with 0.54% of its drivers reporting accidents, and the second class is the high risk class with 20.66% of its drivers reporting accidents; and (4) for the low risk class, drivers with high probability of reporting accidents can be identified by travel-behavior-related characteristics, while for the high risk class, they can be identified by driving-behavior-related characteristics. The driver's familiarity will affect the probability of reporting accidents for both classes. Copyright © 2018 Elsevier Ltd. All rights reserved.

Analysis of near crashes among teen, young adult, and experienced adult drivers using the SHRP2 naturalistic driving study.

PubMed

Seacrist, Thomas; Douglas, Ethan C; Huang, Elaine; Megariotis, James; Prabahar, Abhiti; Kashem, Abyaad; Elzarka, Ayya; Haber, Leora; MacKinney, Taryn; Loeb, Helen

2018-02-28

Motor vehicle crashes are the leading cause of death among young drivers. Though previous research has focused on crash events, near crashes offer additional data to help identify driver errors that could potentially lead to crashes as well as evasive maneuvers used to avoid them. The Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study (NDS) contains extensive data on real-world driving and offers a reliable methodology to quantify and study near crashes. This article presents findings on near crashes and how they compare to crash events among teen, young adult, and experienced adult drivers. A subset from the SHRP2 database consisting of 1,653 near crashes for teen (16-19 years, n = 550), young adult (20-24 years, n = 748), and experienced adult (35-54 years, n = 591) drivers was used. Onboard instrumentation including scene cameras, accelerometers, and Global Positioning System logged time series data at 10 Hz. Scene videos were reviewed for all events to classify near crashes based on 7 types: rear-end, road departure, intersection, head-on, side-swipe, pedestrian/cyclist, and animal. Near crash rates, incident type, secondary tasks, and evasive maneuvers were compared across age groups and between crashes and near crashes. For rear-end near crashes, vehicle dynamic variables including near crash severity, headway distance, time headway, and time to collision at the time of braking were compared across age groups. Crashes and near crashes were combined to compare the frequency of critical events across age. Teen drivers exhibited a significantly higher (P <.01) near crash rate than young adult and experienced adult drivers. The near crash rates were 81.6, 56.6, and 37.3 near crashes per million miles for teens, young adults, and experienced adults, respectively. Teens were also involved in significantly more rear-end (P <.01), road departure (P <.01), side-swipe (P <.01), and animal (P <.05) near crashes compared to young and experienced adults. Teens exhibited a significantly greater (P <.01) critical event rate of 102.2 critical events per million miles compared to 72.4 and 40.0 critical events per million miles for young adults and experienced adults, respectively; the critical event rate ratio was 2.6 and 1.8 for teens and young adults, respectively. To our knowledge, this is the first study to examine near crashes among teen, young adult, and experienced adult drivers using SHRP2 naturalistic data. Near crash and critical event rates significantly decreased with increasing age and driver experience. Overall, teens were more than twice as likely to be involved in critical events compared to experienced adults. These data can be used to develop more targeted driver training programs and help manufacturers design active safety systems based on the most common driving errors for vulnerable road users.

Young drivers' engagement with social interactive technology on their smartphone: Critical beliefs to target in public education messages.

PubMed

Gauld, Cassandra S; Lewis, Ioni M; White, Katherine M; Watson, Barry

2016-11-01

The current study forms part of a larger study based on the Step Approach to Message Design and Testing (SatMDT), a new and innovative framework designed to guide the development and evaluation of health communication messages, including road safety messages. This four step framework is based on several theories, including the Theory of Planned Behaviour. The current study followed steps one and two of the SatMDT framework and utilised a quantitative survey to validate salient beliefs (behavioural, normative, and control) about initiating, monitoring/reading, and responding to social interactive technology on smartphones by N=114 (88F, 26M) young drivers aged 17-25 years. These beliefs had been elicited in a prior in-depth qualitative study. A subsequent critical beliefs analysis identified seven beliefs as potential targets for public education messages, including, 'slow-moving traffic' (control belief - facilitator) for both monitoring/reading and responding behaviours; 'feeling at ease that you had received an expected communication' (behavioural belief -advantage) for monitoring/reading behaviour; and 'friends/peers more likely to approve' (normative belief) for responding behaviour. Potential message content targeting these seven critical beliefs is discussed in accordance with the SatMDT. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Fuzzy Model to Interpret Data of Drive Performances from Patients with Sleep Deprivation

PubMed Central

Sena, Pasquale; Attianese, Paolo; Carbone, Francesca; Pellegrino, Arcangelo; Pinto, Aldo; Villecco, Francesco

2012-01-01

The search for safe vehicles is increasing with both diffusion of high traffic density over the world and availability of new technologies providing sophisticated tools previously impossible to realize. Design and development of the necessary devices may be based on simulation tests that reduce cost allowing trials in many directions. A proper choice of the arrangement of the drive simulators, as much as of the parameters to be monitored, is of basic importance as they can address the design of devices somehow responsible for the drivers safety or, even their lives. This system setup, consisting of a free car simulator equipped with a monitoring system, collects in a nonintrusive way data of the car lateral position within the road lane and of its first derivative. Based on these measured parameters, the system is able to detect symptoms of drowsiness and sleepiness. The analysis is realized by a fuzzy inferential process that provides an immediate warning signal as soon as drowsiness is detected with a high level of certainty. Enhancement of reliability and minimisation of the false alarm rate are obtained by operating continuous comparison between learned driver typical modalities of operation on the control command of the vehicle the pattern recorded. PMID:22969834

Torque coordinating robust control of shifting process for dry dual clutch transmission equipped in a hybrid car

NASA Astrophysics Data System (ADS)

Zhao, Z.-G.; Chen, H.-J.; Yang, Y.-Y.; He, L.

2015-09-01

For a hybrid car equipped with dual clutch transmission (DCT), the coordination control problems of clutches and power sources are investigated while taking full advantage of the integrated starter generator motor's fast response speed and high accuracy (speed and torque). First, a dynamic model of the shifting process is established, the vehicle acceleration is quantified according to the intentions of the driver, and the torque transmitted by clutches is calculated based on the designed disengaging principle during the torque phase. Next, a robust H∞ controller is designed to ensure speed synchronisation despite the existence of model uncertainties, measurement noise, and engine torque lag. The engine torque lag and measurement noise are used as external disturbances to initially modify the output torque of the power source. Additionally, during the torque switch phase, the torque of the power sources is smoothly transitioned to the driver's demanded torque. Finally, the torque of the power sources is further distributed based on the optimisation of system efficiency, and the throttle opening of the engine is constrained to avoid sharp torque variations. The simulation results verify that the proposed control strategies effectively address the problem of coordinating control of clutches and power sources, establishing a foundation for the application of DCT in hybrid cars.

78 FR 32001 - Agency Information Collection Activities; Approval of a New Information Collection Request...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-28

... consultants and academic researchers with expertise in the motor carrier industry and survey design...: Driver and Carrier Surveys Related to Electronic Onboard Recorders (EOBRs), and Potential Harassment... the collection of survey data, the issue of driver harassment and determine the extent to which...

49 CFR 384.225 - CDLIS driver recordkeeping.

Code of Federal Regulations, 2010 CFR

2010-10-01

... operating a CMV. (c) Make CDLIS driver record information required by this section available to the users....231(d). (e) Only the following users or their authorized agents may receive the designated information... procedures. (f) The content of the report provided a user authorized by paragraph (e) of this section from...

Teaching Self Awareness and Group Interaction: A Guide for Driver Education Teachers.

ERIC Educational Resources Information Center

Wisconsin State Dept. of Public Instruction, Madison.

This teaching guide presents materials to help driver education teachers develop classroom discussions designed to raise students' consciousness of themselves, their interactions with others, and the resolution of traffic situations. Small group discussions in the recommended approach. To develop and maintain a conducive classroom atmosphere,…

Driver Improvement Analyst; Basic Training Program. Student Study Guide.

ERIC Educational Resources Information Center

Hale, Allen

As part of the training package for Driver Improvement Analysts, this study guide is designed to serve as the basic reference source for the students/trainees. It reinforces and supplements subject material presented in the Instructor's Lesson Plans. Subjects covered are objectives and requirements, psychology of driving, characteristics of the…

Children's Understanding of Drivers' Intentions

ERIC Educational Resources Information Center

Foot, Hugh C.; Thomson, James A.; Tolmie, Andrew K.; Whelan, Kirstie M.; Morrison, Sheila; Sarvary, Penelope

2006-01-01

To become more skilled as pedestrians, children need to acquire a view of the traffic environment as one in which road users are active agents with different intentions and objectives. This paper describes a simulation study designed to explore children's understanding of drivers' intentions. It also investigated the effect of training children's…

Toms River Drivers Manual 1984-1985.

ERIC Educational Resources Information Center

Thomas, Patricia

The procedures in this manual are designed to establish stability and continuity within the student transportation department of the Toms River Regional Schools in New Jersey. The manual is divided into three sections. Section 1 provides driver and aide specific information. It includes directives related to time clock, spare buses, and…

The Bicycle Driver's Guide.

ERIC Educational Resources Information Center

Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

Designed to emphasize the concept of the bicycle driver vs. the popular term, bicycle rider, this manual contains guidelines on bicycle safety, addressing itself both to parents and children. The main section topics are: (1) parent responsibility; (2) choosing a bicycle, fitting it to the child, and learning to drive; (3) bicycle equipment,…

Pedal force determination respect to ride comfort

NASA Astrophysics Data System (ADS)

Mačužić, Slavica; Lukić, Jovanka; Glišović, Jasna; Miloradović, Danijela

2017-10-01

Automotive ergonomics is a set of knowledge which has a task to design a vehicle to make the passengers feel comfortable. Interior packaging represents an important stage in the vehicle design process, in order to enable the driver to every important aspect of movement. During the process of driving, the driver performs various movements of arms and legs, leading to a certain fatigue. Each seating position in the vehicle, contain certain boundary conditions, and for that reason it was necessary to examine how the seating position affects the driver possibilities. In this paper, the pedal forces were determined by application of Ramsis human model. Different human populations were taken into account. Correlation between subjects’ anthropometrics measures and the foot pedal force pedal was observed. Obtained results were significant input data for vehicle packaging.

Highlights of the Workshop

NASA Technical Reports Server (NTRS)

Noor, Ahmed K.

1997-01-01

Economic stresses are forcing many industries to reduce cost and time-to-market, and to insert emerging technologies into their products. Engineers are asked to design faster, ever more complex systems. Hence, there is a need for novel design paradigms and effective design tools to reduce the design and development times. Several computational tools and facilities have been developed to support the design process. Some of these are described in subsequent presentations. The focus of the workshop is on the computational tools and facilities which have high potential for use in future design environment for aerospace systems. The outline for the introductory remarks is given. First, the characteristics and design drivers for future aerospace systems are outlined; second, simulation-based design environment, and some of its key modules are described; third, the vision for the next-generation design environment being planned by NASA, the UVA ACT Center and JPL is presented. The anticipated major benefits of the planned environment are listed; fourth, some of the government-supported programs related to simulation-based design are listed; and fifth, the objectives and format of the workshop are presented.

Research on Vehicle-Based Driver Status/Performance Monitoring, Part III

DOT National Transportation Integrated Search

1996-09-01

A driver drowsiness detection/alarm/countermeasures system was specified, tested and evaluated, resulting in the development of revised algorithms for the detection of driver drowsiness. Previous algorithms were examined in a test and evaluation stud...

Mature Drivers: Traffic Safety Tips

DOT National Transportation Integrated Search

1996-01-01

This fact sheet, NHTSA Facts: Summer 1996, discusses safety tips for drivers aged 70 and older. It notes that mature drivers: rank lower in aggressive actions; tend to make necessary safety adjustments in their driving, based on their own experience;...

Research On Vehicle-Based Driver Status/Performance Monitoring, Part I

DOT National Transportation Integrated Search

1996-09-01

A driver drowsiness detection/alarm/countermeasures system was specified, tested and evaluated, resulting in the development of revised algorithms for the detection of driver drowsiness. Previous algorithms were examined in a test and evaluation stud...

Characterization of potential driver mutations involved in human breast cancer by computational approaches

PubMed Central

Rajendran, Barani Kumar; Deng, Chu-Xia

2017-01-01

Breast cancer is the second most frequently occurring form of cancer and is also the second most lethal cancer in women worldwide. A genetic mutation is one of the key factors that alter multiple cellular regulatory pathways and drive breast cancer initiation and progression yet nature of these cancer drivers remains elusive. In this article, we have reviewed various computational perspectives and algorithms for exploring breast cancer driver mutation genes. Using both frequency based and mutational exclusivity based approaches, we identified 195 driver genes and shortlisted 63 of them as candidate drivers for breast cancer using various computational approaches. Finally, we conducted network and pathway analysis to explore their functions in breast tumorigenesis including tumor initiation, progression, and metastasis. PMID:28477017

Evaluation of driver fatigue on two channels of EEG data.

PubMed

Li, Wei; He, Qi-chang; Fan, Xiu-min; Fei, Zhi-min

2012-01-11

Electroencephalogram (EEG) data is an effective indicator to evaluate driver fatigue. The 16 channels of EEG data are collected and transformed into three bands (θ, α, and β) in the current paper. First, 12 types of energy parameters are computed based on the EEG data. Then, Grey Relational Analysis (GRA) is introduced to identify the optimal indicator of driver fatigue, after which, the number of significant electrodes is reduced using Kernel Principle Component Analysis (KPCA). Finally, the evaluation model for driver fatigue is established with the regression equation based on the EEG data from two significant electrodes (Fp1 and O1). The experimental results verify that the model is effective in evaluating driver fatigue. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Development of formula varsity race car chassis

NASA Astrophysics Data System (ADS)

Abdullah, M. A.; Mansur, M. R.; Tamaldin, N.; Thanaraj, K.

2013-12-01

Three chassis designs have been developed using commercial computer aided design (CAD) software. The design is based on the specifications of UTeM Formula VarsityTM 2012 (FV2012). The selection of the design is derived from weighted matrix which consists of reliability, cost, time consumption and weight. The score of the matrix is formulated based on relative weighted factor among the selections. All three designs are then fabricated using selected materials available. The actual cost, time consumption and weight of the chassis's are compared with the theoretical weighted scores. Standard processes of cuttings, fittings and welding are performed in chassis mock up and fabrication. The chassis is later assembled together with suspension systems, steering linkages, brake systems, engine system, and drive shaft systems. Once the chassis is assembled, the studies of driver's ergonomic and part accessibility are performed. The completion in final fittings and assembly of the race car and its reliability demonstrate an outstanding design for manufacturing (DFM) practices of the chassis.

Alcohol and drug involvement in motorcycle driver injuries in the city of Sao Paulo, Brazil: Analysis of crash culpability and other associated factors.

PubMed

de Carvalho, Heraclito Barbosa; Andreuccetti, Gabriel; Rezende, Marcelo Rosa; Bernini, Celso; Silva, Jorge Santos; Leyton, Vilma; D'Andréa Greve, Julia Maria

2016-05-01

Earlier studies have already identified that a greater proportion of injured drivers are under the effects of illicit drugs than alcohol in Brazil, but the crash risk attributable to each substance is still unknown. Injured motorcycle drivers who were involved in traffic accidents in the West Zone of the city of Sao Paulo were recruited for a cross-sectional study based on crash culpability analysis. Alcohol and drug positivity among drivers was evaluated according to their responsibility for the crash. Culpability ratios were generated based on the proportion of drivers who were deemed culpable in relation to those considered not culpable according to the use of drugs and alcohol. Of the 273 drivers recruited, 10.6% tested positive for alcohol. Among those who were also tested for drugs (n=232), 20.3% had consumed either alcohol and/or other drugs, 15.5% of whom were positive only for drugs other than alcohol, specifically cannabis and cocaine. Drivers who tested positive for alcohol were significantly less likely to possess a valid driver's license and to report driving professionally, whereas those who had consumed only drugs were more likely to drive professionally. The culpability ratio estimated for alcohol-positive drivers was three times higher than that for alcohol-free drivers, showing a superior ratio than drivers who had consumed only drugs other than alcohol, who presented a 1.7 times higher culpability ratio than drug-free drivers. Substance use was overrepresented among culpable motorcycle drivers, with alcohol showing a greater contribution to crash culpability than other drugs. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Analytical Formulation for Sizing and Estimating the Dimensions and Weight of Wind Turbine Hub and Drivetrain Components

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Y.; Parsons, T.; King, R.

This report summarizes the theory, verification, and validation of a new sizing tool for wind turbine drivetrain components, the Drivetrain Systems Engineering (DriveSE) tool. DriveSE calculates the dimensions and mass properties of the hub, main shaft, main bearing(s), gearbox, bedplate, transformer if up-tower, and yaw system. The level of fi¬ delity for each component varies depending on whether semiempirical parametric or physics-based models are used. The physics-based models have internal iteration schemes based on system constraints and design criteria. Every model is validated against available industry data or finite-element analysis. The verification and validation results show that the models reasonablymore » capture primary drivers for the sizing and design of major drivetrain components.« less

Using farmers' attitude and social pressures to design voluntary Bluetongue vaccination strategies.

PubMed

Sok, J; Hogeveen, H; Elbers, A R W; Oude Lansink, A G J M

2016-10-01

Understanding the context and drivers of farmers' decision-making is critical to designing successful voluntary disease control interventions. This study uses a questionnaire based on the Reasoned Action Approach framework to assess the determinants of farmers' intention to participate in a hypothetical reactive vaccination scheme against Bluetongue. Results suggest that farmers' attitude and social pressures best explained intention. A mix of policy instruments can be used in a complementary way to motivate voluntary vaccination based on the finding that participation is influenced by both internal and external motivation. Next to informational and incentive-based instruments, social pressures, which stem from different type of perceived norms, can spur farmers' vaccination behaviour and serve as catalysts in voluntary vaccination schemes. Copyright © 2016 Elsevier B.V. All rights reserved.

HEARING IMPAIRMENT AND HYPERTENSION AMONG LONG DISTANCE BUS DRIVERS

PubMed Central

Abdelmoneim, Ismail

2003-01-01

Objectives: To investigate the prevalence of possible hearing impairment and hypertension in long distance bus drivers compared to the city bus drivers in Abha city. Methods: This was a cross-sectional study involving 62 long distance bus drivers and 46 city bus drivers from October 2001 to March 2002. A specially-designed questionnaire was administered to the drivers to explore some of their socioeconomic backgrounds. A pure tone air conduction audiometry and blood pressure measurements were performed. Results: Long distance bus drivers’ workload is significantly higher than that of city drivers (total weekly hours 64.0±14.3 compared to 46.7±5.5). Hearing impairment was significantly more among long distance drivers in the frequencies of 250, 500, 1000 and 2000 Hz especially in the left ear even after age corrections. The prevalence of mild hearing loss and hypertension were also higher among the long distance drivers (19.4% vs 4.5% and 38.7% vs 13% respectively). Conclusion and recommendations: This study showed more hearing affection and a higher prevalence of hypertension among long distance bus drivers than their counterparts operating in the city. Their hearing acuity should be tested before they start work and regularly afterwards. The stresses and strains of the job should be further studied and relieved; and regular health checks including blood pressure monitoring are to be instituted. PMID:23012034

Background music as a risk factor for distraction among young-novice drivers.

PubMed

Brodsky, Warren; Slor, Zack

2013-10-01

There are countless beliefs about the power of music during driving. The last thing one would think about is: how safe is it to listen or sing to music? Unfortunately, collisions linked to music devices have been known for some time; adjusting the radio controls, swapping tape-cassettes and compact-discs, or searching through MP3 files, are all forms of distraction that can result in a near-crash or crash. While the decrement of vehicular performance can also occur from capacity interference to central attention, whether or not music listening is a contributing factor to distraction is relatively unknown. The current study explored the effects of driver-preferred music on driver behavior. 85 young-novice drivers completed six trips in an instrumented Learners Vehicle. The study found that all participants committed at-least 3 driver deficiencies; 27 needed a verbal warning/command and 17 required a steering or braking intervention to prevent an accident. While there were elevated positive moods and enjoyment for trips with driver-preferred music, this background also produced the most frequent severe driver miscalculations and inaccuracies, violations, and aggressive driving. However, trips with music structurally designed to generate moderate levels of perceptual complexity, improved driver behavior and increased driver safety. The study is the first within-subjects on-road high-dose double-exposure clinical-trial investigation of musical stimuli on driver behavior. Copyright © 2013 Elsevier Ltd. All rights reserved.

The influence of anger, impulsivity, sensation seeking and driver attitudes on risky driving behaviour among post-graduate university students in Durban, South Africa.

PubMed

Bachoo, Shaneel; Bhagwanjee, Anil; Govender, Kaymarlin

2013-06-01

Road traffic accidents (RTAs) constitute a serious global health risk, and evidence suggests that young drivers are significantly overrepresented among those injured or killed in RTAs. This study explores the role of anger, impulsivity, sensation seeking and driver attitudes as correlates for risky driving practices among drivers, drawing comparisons between age and gender. The study used a cross-sectional survey design, with a sample of 306 post-graduate university students from two universities in Durban, South Africa, who completed the self-administered questionnaire. The results indicate that drivers with higher driver anger, sensation seeking, urgency, and with a lack of premeditation and perseverance in daily activities were statistically more likely to report riskier driving acts. Males reported significantly more acts of risky driving behaviour (RDB) than females. Driver attitudes significantly predicted self-reported acts of RDB on most indicators. Older drivers (25 years and older) had safer driver attitudes and a lower sense of sensation seeking and urgency in life. Interventions targeting young drivers, which focus on impeding the manifestation of anger, impulsivity and sensation seeking are recommended. Also, the empirical support for the attitude-behaviour hypothesis evidenced in this study vindicates the development or continuation of interventions that focus on this dynamic. Copyright © 2013 Elsevier Ltd. All rights reserved.

Design and Implementation of Real-Time Vehicular Camera for Driver Assistance and Traffic Congestion Estimation

PubMed Central

Son, Sanghyun; Baek, Yunju

2015-01-01

As society has developed, the number of vehicles has increased and road conditions have become complicated, increasing the risk of crashes. Therefore, a service that provides safe vehicle control and various types of information to the driver is urgently needed. In this study, we designed and implemented a real-time traffic information system and a smart camera device for smart driver assistance systems. We selected a commercial device for the smart driver assistance systems, and applied a computer vision algorithm to perform image recognition. For application to the dynamic region of interest, dynamic frame skip methods were implemented to perform parallel processing in order to enable real-time operation. In addition, we designed and implemented a model to estimate congestion by analyzing traffic information. The performance of the proposed method was evaluated using images of a real road environment. We found that the processing time improved by 15.4 times when all the proposed methods were applied in the application. Further, we found experimentally that there was little or no change in the recognition accuracy when the proposed method was applied. Using the traffic congestion estimation model, we also found that the average error rate of the proposed model was 5.3%. PMID:26295230

Design and Implementation of Real-Time Vehicular Camera for Driver Assistance and Traffic Congestion Estimation.

PubMed

Son, Sanghyun; Baek, Yunju

2015-08-18

As society has developed, the number of vehicles has increased and road conditions have become complicated, increasing the risk of crashes. Therefore, a service that provides safe vehicle control and various types of information to the driver is urgently needed. In this study, we designed and implemented a real-time traffic information system and a smart camera device for smart driver assistance systems. We selected a commercial device for the smart driver assistance systems, and applied a computer vision algorithm to perform image recognition. For application to the dynamic region of interest, dynamic frame skip methods were implemented to perform parallel processing in order to enable real-time operation. In addition, we designed and implemented a model to estimate congestion by analyzing traffic information. The performance of the proposed method was evaluated using images of a real road environment. We found that the processing time improved by 15.4 times when all the proposed methods were applied in the application. Further, we found experimentally that there was little or no change in the recognition accuracy when the proposed method was applied. Using the traffic congestion estimation model, we also found that the average error rate of the proposed model was 5.3%.

Fatigue in Younger and Older Drivers: Effectiveness of an Alertness-Maintaining Task.

PubMed

Song, Woojin; Woon, Fu L; Doong, Alice; Persad, Carol; Tijerina, Louis; Pandit, Pooja; Cline, Carol; Giordani, Bruno

2017-09-01

The aim of this study was to examine the effects of an alertness-maintaining task (AMT) in older, fatigued drivers. Fatigue during driving increases crash risk, and previous research suggests that alertness and driving in younger adults may be improved using a secondary AMT during boring, fatigue-eliciting drives. However, the potential impact of an AMT on driving has not been investigated in older drivers whose ability to complete dual tasks has been shown to decline and therefore may be negatively affected with an AMT in driving. Younger ( n = 29) and older drivers ( n = 39) participated in a 50-minute simulated drive designed to induce fatigue, followed by four 10-minute sessions alternating between driving with and without an AMT. Younger drivers were significantly more affected by fatigue on driving performance than were older drivers but benefitted significantly from the AMT. Older drivers did not demonstrate increased driver errors with fatigue, and driving did not deteriorate significantly during participation in the AMT condition, although their speed was significantly more variable with the AMT. Consistent with earlier research, an AMT applied during fatiguing driving is effective in improving alertness and reducing driving errors in younger drivers. Importantly, older drivers were relatively unaffected by fatigue, and use of an AMT did not detrimentally affect their driving performance. These results support the potential use of an AMT as a new automotive technology to improve fatigue and promote driver safety, though the benefits of such technology may differ between different age groups.

The flight telerobotic servicer Tinman concept: System design drivers and task analysis

NASA Technical Reports Server (NTRS)

Andary, J. F.; Hewitt, D. R.; Hinkal, S. W.

1989-01-01

A study was conducted to develop a preliminary definition of the Flight Telerobotic Servicer (FTS) that could be used to understand the operational concepts and scenarios for the FTS. Called the Tinman, this design concept was also used to begin the process of establishing resources and interfaces for the FTS on Space Station Freedom, the National Space Transportation System shuttle orbiter, and the Orbital Maneuvering vehicle. Starting with an analysis of the requirements and task capabilities as stated in the Phase B study requirements document, the study identified eight major design drivers for the FTS. Each of these design drivers and their impacts on the Tinman design concept are described. Next, the planning that is currently underway for providing resources for the FTS on Space Station Freedom is discussed, including up to 2000 W of peak power, up to four color video channels, and command and data rates up to 500 kbps between the telerobot and the control station. Finally, an example is presented to show how the Tinman design concept was used to analyze task scenarios and explore the operational capabilities of the FTS. A structured methodology using a standard terminology consistent with the NASA/National Bureau of Standards Standard Reference Model for Telerobot Control System Architecture (NASREM) was developed for this analysis.

Multilevel corporate environmental responsibility.

PubMed

Karassin, Orr; Bar-Haim, Aviad

2016-12-01

The multilevel empirical study of the antecedents of corporate social responsibility (CSR) has been identified as "the first knowledge gap" in CSR research. Based on an extensive literature review, the present study outlines a conceptual multilevel model of CSR, then designs and empirically validates an operational multilevel model of the principal driving factors affecting corporate environmental responsibility (CER), as a measure of CSR. Both conceptual and operational models incorporate three levels of analysis: institutional, organizational, and individual. The multilevel nature of the design allows for the assessment of the relative importance of the levels and of their components in the achievement of CER. Unweighted least squares (ULS) regression analysis reveals that the institutional-level variables have medium relationships with CER, some variables having a negative effect. The organizational level is revealed as having strong and positive significant relationships with CER, with organizational culture and managers' attitudes and behaviors as significant driving forces. The study demonstrates the importance of multilevel analysis in improving the understanding of CSR drivers, relative to single level models, even if the significance of specific drivers and levels may vary by context. Copyright © 2016 Elsevier Ltd. All rights reserved.

The South African Astronomical Observatory instrumentation software architecture and the SHOC instruments

NASA Astrophysics Data System (ADS)

van Gend, Carel; Lombaard, Briehan; Sickafoose, Amanda; Whittal, Hamish

2016-07-01

Until recently, software for instruments on the smaller telescopes at the South African Astronomical Observatory (SAAO) has not been designed for remote accessibility and frequently has not been developed using modern software best-practice. We describe a software architecture we have implemented for use with new and upgraded instruments at the SAAO. The architecture was designed to allow for multiple components and to be fast, reliable, remotely- operable, support different user interfaces, employ as much non-proprietary software as possible, and to take future-proofing into consideration. Individual component drivers exist as standalone processes, communicating over a network. A controller layer coordinates the various components, and allows a variety of user interfaces to be used. The Sutherland High-speed Optical Cameras (SHOC) instruments incorporate an Andor electron-multiplying CCD camera, a GPS unit for accurate timing and a pair of filter wheels. We have applied the new architecture to the SHOC instruments, with the camera driver developed using Andor's software development kit. We have used this to develop an innovative web-based user-interface to the instrument.

Magnetorheological fluid based automotive steer-by-wire systems

NASA Astrophysics Data System (ADS)

Ahmadkhanlou, Farzad; Washington, Gregory N.; Bechtel, Stephen E.; Wang, Yingru

2006-03-01

The idea of this paper is to design a Magnetorheological (MR) fluid based damper for steer-by-wire systems to provide sensory feedback to the driver. The advantages of using MR fluids in haptic devices stem from the increase in transparency gained from the lightweight semiactive system and controller implementation. The performance of MR fluid based steer-by wire system depends on MR fluid model and specifications, MR damper geometry, and the control algorithm. All of these factors are addressed in this study. The experimental results show the improvements in steer-by-wire by adding force feedback to the system.

Distributed data collection and supervision based on web sensor

NASA Astrophysics Data System (ADS)

He, Pengju; Dai, Guanzhong; Fu, Lei; Li, Xiangjun

2006-11-01

As a node in Internet/Intranet, web sensor has been promoted in recent years and wildly applied in remote manufactory, workshop measurement and control field. However, the conventional scheme can only support HTTP protocol, and the remote users supervise and control the collected data published by web in the standard browser because of the limited resource of the microprocessor in the sensor; moreover, only one node of data acquirement can be supervised and controlled in one instant therefore the requirement of centralized remote supervision, control and data process can not be satisfied in some fields. In this paper, the centralized remote supervision, control and data process by the web sensor are proposed and implemented by the principle of device driver program. The useless information of the every collected web page embedded in the sensor is filtered and the useful data is transmitted to the real-time database in the workstation, and different filter algorithms are designed for different sensors possessing independent web pages. Every sensor node has its own filter program of web, called "web data collection driver program", the collecting details are shielded, and the supervision, control and configuration software can be implemented by the call of web data collection driver program just like the use of the I/O driver program. The proposed technology can be applied in the data acquirement where relative low real-time is required.

Network analysis of genomic alteration profiles reveals co-altered functional modules and driver genes for glioblastoma.

PubMed

Gu, Yunyan; Wang, Hongwei; Qin, Yao; Zhang, Yujing; Zhao, Wenyuan; Qi, Lishuang; Zhang, Yuannv; Wang, Chenguang; Guo, Zheng

2013-03-01

The heterogeneity of genetic alterations in human cancer genomes presents a major challenge to advancing our understanding of cancer mechanisms and identifying cancer driver genes. To tackle this heterogeneity problem, many approaches have been proposed to investigate genetic alterations and predict driver genes at the individual pathway level. However, most of these approaches ignore the correlation of alteration events between pathways and miss many genes with rare alterations collectively contributing to carcinogenesis. Here, we devise a network-based approach to capture the cooperative functional modules hidden in genome-wide somatic mutation and copy number alteration profiles of glioblastoma (GBM) from The Cancer Genome Atlas (TCGA), where a module is a set of altered genes with dense interactions in the protein interaction network. We identify 7 pairs of significantly co-altered modules that involve the main pathways known to be altered in GBM (TP53, RB and RTK signaling pathways) and highlight the striking co-occurring alterations among these GBM pathways. By taking into account the non-random correlation of gene alterations, the property of co-alteration could distinguish oncogenic modules that contain driver genes involved in the progression of GBM. The collaboration among cancer pathways suggests that the redundant models and aggravating models could shed new light on the potential mechanisms during carcinogenesis and provide new indications for the design of cancer therapeutic strategies.

Contributing Factors to Driver's Over-trust in a Driving Support System for Workload Reduction

NASA Astrophysics Data System (ADS)

Itoh, Makoto

Avoiding over-trust in machines is a vital issue in order to establish intelligent driver support systems. It is necessary to distinguish systems for workload reduction from systems for accident prevention/mitigation. This study focuses on over-trust in an Adaptive Cruise Control (ACC) system as a typical driving support system for workload reduction. By conducting an experiment, we obtained a case in which a driver trusted the ACC system too much. Concretely speaking, the driver just watched the ACC system crashing into a stopped car even though the ACC system was designed to ignore such stopped cars. This paper investigates possible contributing factors to the driver' s over-trust in the ACC system. The results suggest that emerging trust in the dimension of performance may cause over-trust in the dimension of method or purpose.

Mass drivers. 3: Engineering

NASA Technical Reports Server (NTRS)

Arnold, W.; Bowen, S.; Cohen, S.; Fine, K.; Kaplan, D.; Kolm, M.; Kolm, H.; Newman, J.; Oneill, G. K.; Snow, W.

1979-01-01

The last of a series of three papers by the Mass-Driver Group of the 1977 Ames Summer Study is presented. It develops the engineering principles required to implement the basic mass-driver. Optimum component mass trade-offs are derived from a set of four input parameters, and the program used to design a lunar launcher. The mass optimization procedures is then incorporated into a more comprehensive mission optimization program called OPT-4, which evaluates an optimized mass-driver reaction engine and its performance in a range of specified missions. Finally, this paper discusses, to the extent that time permitted, certain peripheral problems: heating effects in buckets due to magnetic field ripple; an approximate derivation of guide force profiles; the mechanics of inserting and releasing payloads; the reaction mass orbits; and a proposed research and development plan for implementing mass drivers.

Vehicle-based drowsy driver detection : current status and future prospects

DOT National Transportation Integrated Search

1994-01-01

Driver drowsiness is a major, though elusive, cause of traffic crashes. As part of its : IVHS/human factors program, NHTSA is supporting research to develop in-vehicle systems . : to continuously monitor driver alertness and performance. Scientific s...

Using a 'value-added' approach for contextual design of geographic information.

PubMed

May, Andrew J

2013-11-01

The aim of this article is to demonstrate how a 'value-added' approach can be used for user-centred design of geographic information. An information science perspective was used, with value being the difference in outcomes arising from alternative information sets. Sixteen drivers navigated a complex, unfamiliar urban route, using visual and verbal instructions representing the distance-to-turn and junction layout information presented by typical satellite navigation systems. Data measuring driving errors, navigation errors and driver confidence were collected throughout the trial. The results show how driver performance varied considerably according to the geographic context at specific locations, and that there are specific opportunities to add value with enhanced geographical information. The conclusions are that a value-added approach facilitates a more explicit focus on 'desired' (and feasible) levels of end user performance with different information sets, and is a potentially effective approach to user-centred design of geographic information. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Driving Performance After Self-Regulated Control Transitions in Highly Automated Vehicles.

PubMed

Eriksson, Alexander; Stanton, Neville A

2017-12-01

This study aims to explore whether driver-paced, noncritical transitions of control may counteract some of the aftereffects observed in the contemporary literature, resulting in higher levels of vehicle control. Research into control transitions in highly automated driving has focused on urgent scenarios where drivers are given a relatively short time span to respond to a request to resume manual control, resulting in seemingly scrambled control when manual control is resumed. Twenty-six drivers drove two scenarios with an automated driving feature activated. Drivers were asked to read a newspaper or monitor the system and relinquish or resume control from the automation when prompted by vehicle systems. Driving performance in terms of lane positioning and steering behavior was assessed for 20 seconds post resuming control to capture the resulting level of control. It was found that lane positioning was virtually unaffected for the duration of the 20-second time span in both automated conditions compared to the manual baseline when drivers resumed manual control; however, significant increases in the standard deviation of steering input were found for both automated conditions compared to baseline. No significant differences were found between the two automated conditions. The results indicate that when drivers self-paced the transfer back to manual control they exhibit less of the detrimental effects observed in system-paced conditions. It was shown that self-paced transitions could reduce the risk of accidents near the edge of the operational design domain. Vehicle manufacturers must consider these benefits when designing contemporary systems.

Evaluating the effectiveness of a road safety education intervention for pre-drivers: an application of the theory of planned behaviour.

PubMed

Poulter, Damian R; McKenna, Frank P

2010-06-01

Young drivers are overrepresented in road traffic fatalities and collisions. Attempts to address this problem with pre-driver education have not met with unambiguous success. However, there is a lack of research on whether pre-driver education can change psychological antecedents to behaviour. The framework of the theory of planned behaviour (TPB) was employed to assess the effectiveness of an educational intervention used across the UK that aims to improve attitudes to road safety in pre-drivers. Secondary school students aged 15-16 years participated in the research, drawn from 12 schools in the UK. A total of 199 students took part in Expt 1 and 430 in Expt 2. Expt 1 employed a within-participants design to measure any changes in road safety beliefs from pre- to post-intervention and 5-month follow-up. Expt 2 used a between-participants design to test whether any changes were genuine or due to experimenter effects. Results of Expt 1 revealed a small, short-term improvement in some pre-driver beliefs immediately following the educational intervention, but no effect on other beliefs, and some evidence of unintended outcomes. The small, significant improvements found in Expt 1 were replicated in Expt 2, which is consistent with there being a genuine effect. Considering evidence from both experiments suggests the effectiveness of road safety education interventions are at best short term, and limited to some but not all psychological factors, with some risk of unintended consequences.

Factors correlated with traffic accidents as a basis for evaluating Advanced Driver Assistance Systems.

PubMed

Staubach, Maria

2009-09-01

This study aims to identify factors which influence and cause errors in traffic accidents and to use these as a basis for information to guide the application and design of driver assistance systems. A total of 474 accidents were examined in depth for this study by means of a psychological survey, data from accident reports, and technical reconstruction information. An error analysis was subsequently carried out, taking into account the driver, environment, and vehicle sub-systems. Results showed that all accidents were influenced by errors as a consequence of distraction and reduced activity. For crossroad accidents, there were further errors resulting from sight obstruction, masked stimuli, focus errors, and law infringements. Lane departure crashes were additionally caused by errors as a result of masked stimuli, law infringements, expectation errors as well as objective and action slips, while same direction accidents occurred additionally because of focus errors, expectation errors, and objective and action slips. Most accidents were influenced by multiple factors. There is a safety potential for Advanced Driver Assistance Systems (ADAS), which support the driver in information assimilation and help to avoid distraction and reduced activity. The design of the ADAS is dependent on the specific influencing factors of the accident type.

Battery electric vehicles - implications for the driver interface.

PubMed

Neumann, Isabel; Krems, Josef F

2016-03-01

The current study examines the human-machine interface of a battery electric vehicle (BEV) from a user-perspective, focussing on the evaluation of BEV-specific displays, the relevance of provided information and challenges for drivers due to the concept of electricity in a road vehicle. A sample of 40 users drove a BEV for 6 months. Data were gathered at three points of data collection. Participants perceived the BEV-specific displays as only moderately reliable and helpful for estimating the displayed parameters. This was even less the case after driving the BEV for 3 months. A taxonomy of user requirements was compiled revealing the need for improved and additional information, especially regarding energy consumption and efficiency. Drivers had difficulty understanding electrical units and the energy consumption of the BEV. On the background of general principles for display design, results provide implications how to display relevant information and how to facilitate drivers' understanding of energy consumption in BEVs. Practitioner Summary: Battery electric vehicle (BEV) displays need to incorporate new information. A taxonomy of user requirements was compiled revealing the need for improved and additional information in the BEV interface. Furthermore, drivers had trouble understanding electrical units and energy consumption; therefore, appropriate assistance is required. Design principles which are specifically important in the BEV context are discussed.

Motor vehicle driver injury and socioeconomic status: a cohort study with prospective and retrospective driver injuries

PubMed Central

Whitlock, G; Norton, R; Clark, T; Pledger, M; Jackson, R; MacMahon, S

2003-01-01

Study objective: To investigate the association between motor vehicle driver injury and socioeconomic status. Design: Cohort study with prospective and retrospective outcomes. Setting: New Zealand. Participants: 10 525 adults (volunteer sample of a multi-industry workforce, n=8008; and a random sample of urban electoral rolls, n=2517). Outcome measure: Motor vehicle driver injury resulting in admission of the driver to hospital or the driver's death, or both, during the period 1988–98; hospitalisation and mortality data were obtained by record linkage to national health databases. Main results: After adjustment for age and sex, driver injury risk was inversely associated with both occupational status (p for linear trend <0.0001) and educational level (p for linear trend =0.007). Participants in the lowest approximate quartile of occupational status were four times as likely (HR 4.17, 95% CI 2.31 to 7.55) to have experienced a driver injury during follow up as participants in the highest approximate quartile. Participants who had been to secondary school for less than two years were twice as likely (HR 2.26, 95% CI 1.34 to 3.81) to have experienced a driver injury as those who had been to university or polytechnic. There was little evidence that driver injury risk was associated with neighbourhood income (p for linear trend =0.12) Conclusions: Occupational status and educational level seem to be important determinants of driver injury risk. Driver injury countermeasures should be targeted to people in low status occupations, as well as to people with comparatively little formal education. PMID:12821697

Driver fatigue detection based on eye state.

PubMed

Lin, Lizong; Huang, Chao; Ni, Xiaopeng; Wang, Jiawen; Zhang, Hao; Li, Xiao; Qian, Zhiqin

2015-01-01

Nowadays, more and more traffic accidents occur because of driver fatigue. In order to reduce and prevent it, in this study, a calculation method using PERCLOS (percentage of eye closure time) parameter characteristics based on machine vision was developed. It determined whether a driver's eyes were in a fatigue state according to the PERCLOS value. The overall workflow solutions included face detection and tracking, detection and location of the human eye, human eye tracking, eye state recognition, and driver fatigue testing. The key aspects of the detection system incorporated the detection and location of human eyes and driver fatigue testing. The simplified method of measuring the PERCLOS value of the driver was to calculate the ratio of the eyes being open and closed with the total number of frames for a given period. If the eyes were closed more than the set threshold in the total number of frames, the system would alert the driver. Through many experiments, it was shown that besides the simple detection algorithm, the rapid computing speed, and the high detection and recognition accuracies of the system, the system was demonstrated to be in accord with the real-time requirements of a driver fatigue detection system.

Toxoplasma gondii infection in interstate truck drivers: a case-control seroprevalence study.

PubMed

Alvarado-Esquivel, Cosme; Pacheco-Vega, Sandy Janet; Hernández-Tinoco, Jesús; Salcedo-Jáquez, Misael; Sánchez-Anguiano, Luis Francisco; Berumen-Segovia, Luis Omar; Rábago-Sánchez, Elizabeth; Liesenfeld, Oliver

2015-02-05

Infection with Toxoplasma gondii can be acquired via the ingestion of undercooked or raw meat containing tissue cysts, or via ingestion of water contaminated with oocysts. Professional long distance truck driving may have epidemiological importance for food-borne infections since drivers eat out of home and in places where hygiene and cooking practices are uncertain. We aimed to determine whether interstate truck drivers in Durango, Mexico have an increased risk of infection with T. gondii as indicated by seropositivity; and to determine the socio-demographic, work, clinical, and behavioral characteristics associated with T. gondii seropositivity in interstate truck drivers. Through a case-control study design, 192 truck drivers and 192 controls from the general population of the same region matched by gender and age were examined with enzyme-linked immunoassays for the presence of anti-Toxoplasma IgG and IgM antibodies. Socio-demographic, work, clinical and behavioral characteristics from the truck drivers were obtained. Anti-T. gondii IgG antibodies were found in 23 (12.0%) of 192 truck drivers and in 13 (6.8%) of 192 controls (OR = 21.0; 95% CI: 1.23-358.38; P = 0.002). Anti-T. gondii IgM antibodies were found in 7 (3.6%) cases and in 7 (3.6%) controls (P = 1.00). The seroprevalence of T. gondii infection was higher in drivers with reflex impairment than in those without this impairment (4/13, 30.8% vs 19/179, 10.6%, respectively; P = 0.05), and in drivers with hearing impairment than in those without this impairment (3/7, 42.9% vs 20/185, 10.8%, respectively; P = 0.03). Multivariate analysis of work and behavioral characteristics of truck drives showed positive associations of T. gondii exposure with trips to the south of Mexico (OR = 3.11; 95% CI: 1.02-9.44; P = 0.04) and consumption of horse meat (OR = 5.18; 95% CI: 1.62-16.55; P = 0.005). Results suggest that interstate truck drivers may have an increased risk for T. gondii infection, and that T. gondii exposure may be impacting neurological functions in truck drivers. Contributing factors for T. gondii exposure should be taken into account for the design of optimal prevention measures against T. gondii infection.

The effect of performance feedback on drivers' hazard perception ability and self-ratings.

PubMed

Horswill, Mark S; Garth, Megan; Hill, Andrew; Watson, Marcus O

2017-04-01

Drivers' hazard perception ability has been found to predict crash risk, and novice drivers appear to be particularly poor at this skill. This competency appears to develop only slowly with experience, and this could partially be a result of poor quality performance feedback. We report an experiment in which we provided high-quality artificial feedback on individual drivers' performance in a validated video-based hazard perception test via either: (1) a graph-based comparison of hazard perception response times between the test-taker, the average driver, and an expert driver; (2) a video-based comparison between the same groups; or (3) both. All three types of feedback resulted in both an improvement in hazard perception performance and a reduction in self-rated hazard perception skill, compared with a no-feedback control group. Video-based and graph-based feedback combined resulted in a greater improvement in hazard perception performance than either of the individual components, which did not differ from one another. All three types of feedback eliminated participants' self-enhancement bias for hazard perception skill. Participants judged both interventions involving video feedback to be significantly more likely to improve their real-world driving than the no feedback control group. While all three forms of feedback had some value, the combined video and graph feedback intervention appeared to be the most effective across all outcome measures. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of Data Acquisition Card Driver for ICRH System on EAST

NASA Astrophysics Data System (ADS)

Liu, Daming; Luo, Jiarong; Zhao, Yanping; Qin, Chengming

2008-04-01

Presented in this paper is the development of the driver for the data acquisition card with a peripheral component interconnection (PCI) local bus on the ion cyclotron range of frequency heating (ICRH) system. The driver is mainly aimed at the embedded VxWorks system (real-time operating system) which is widely used in various fields of real-time systems. An efficient way is employed to develop this driver, which will advance the real-time control of the ICRH system on the experimental advanced superconductor tokamak (EAST). The driver is designed using the TORNADO integrated development environment (IDE), and implemented in C plus language. The details include the hardware configuration, analogue/digital (A/D) and digital/analogue (D/A) conversion, input and output (I/O) operation of the driver to support over five cards. The data acquisition card can be manipulated in a low-level program and meet the requirements of A/D conversion and D/A outputs.