Comparative Genomics Analyses Reveal Extensive Chromosome Colinearity and Novel Quantitative Trait Loci in Eucalyptus.

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Fagen Li

Full Text Available Dense genetic maps, along with quantitative trait loci (QTLs detected on such maps, are powerful tools for genomics and molecular breeding studies. In the important woody genus Eucalyptus, the recent release of E. grandis genome sequence allows for sequence-based genomic comparison and searching for positional candidate genes within QTL regions. Here, dense genetic maps were constructed for E. urophylla and E. tereticornis using genomic simple sequence repeats (SSR, expressed sequence tag (EST derived SSR, EST-derived cleaved amplified polymorphic sequence (EST-CAPS, and diversity arrays technology (DArT markers. The E. urophylla and E. tereticornis maps comprised 700 and 585 markers across 11 linkage groups, totaling at 1,208.2 and 1,241.4 cM in length, respectively. Extensive synteny and colinearity were observed as compared to three earlier DArT-based eucalypt maps (two maps with E. grandis × E. urophylla and one map of E. globulus and with the E. grandis genome sequence. Fifty-three QTLs for growth (10-56 months of age and wood density (56 months were identified in 22 discrete regions on both maps, in which only one colocalizaiton was found between growth and wood density. Novel QTLs were revealed as compared with those previously detected on DArT-based maps for similar ages in Eucalyptus. Eleven to 585 positional candidate genes were obained for a 56-month-old QTL through aligning QTL confidence interval with the E. grandis genome. These results will assist in comparative genomics studies, targeted gene characterization, and marker-assisted selection in Eucalyptus and the related taxa.

Quantum driving protocols for a two-level system: From generalized Landau-Zener sweeps to transitionless control

DEFF Research Database (Denmark)

Malossi, Nicola; Bason, Mark George; Viteau, Matthieu

2013-01-01

We present experimental results on the preparation of a desired quantum state in a two-level system with the maximum possible fidelity using driving protocols ranging from generalizations of the linear Landau-Zener protocol to transitionless driving protocols that ensure perfect following of the ...

Generalized matrix method for transmission of neutrons through multilayer magnetic system with non-colinear magnetization

International Nuclear Information System (INIS)

Radu, F.; Ignatovich, V.K.

1999-01-01

A generalized matrix method (GMM) for reflection and transmission of polarized and nonpolarized neutrons for multilayer systems with non-colinear magnetization of neighboring layers is developed. Several methods exist for calculation of the reflection and transmission coefficients of the multilayer systems (MS). We consider here only two of them. One is the recurrence method (RM), and another one is the matrix method. Previously these methods were used for scalar particles and for spinor particles. In the last case a limitation was imposed on the directions of the magnetization of different layers: they were required to lie in the plane parallel to the layers. In 1995 Fermon has described a different approach of the neutrons in MS. Here, the behaviour of the wave inside the layers depends on the position within the plane. The RM, as shown by us earlier, permits to treat multilayer systems with arbitrary directions of the magnetization. We show how to treat these systems with the updated matrix method, which we call the generalized matrix method. In the GMM method the transmission and reflection of a layered system are obtained by finding a 4 x 4 matrix, which is a product of elementary 4 x 4 matrices related to the different layers, and in the RM the solution is found by recurrent application of the same procedure of finding the reflection and transmission matrices for a continuously increasing number of layers. The RM method permits to use a simple algorithm to write analytical formulas for the reflection and transmission. However, for more or less complicated systems these formulas become useless and one needs to do numerical calculations. The GMM does not give a simple analytical algorithm, but it gives a very simple numerical algorithm. We have developed two computer codes for computing the coefficients of reflection and transmission of a layered system using the GMM and RM methods. The calculated reflectivities R ++ and R +- for a polarized beam which fall on

Common sole larvae survive high levels of pile-driving sound in controlled exposure experiments.

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Loes J Bolle

Full Text Available In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at which (sub-lethal effects occur is limited for juvenile and adult fish, and virtually non-existent for fish eggs and larvae. A device was developed in which fish larvae can be exposed to underwater sound. It consists of a rigid-walled cylindrical chamber driven by an electro-dynamical sound projector. Samples of up to 100 larvae can be exposed simultaneously to a homogeneously distributed sound pressure and particle velocity field. Recorded pile-driving sounds could be reproduced accurately in the frequency range between 50 and 1000 Hz, at zero to peak pressure levels up to 210 dB re 1µPa(2 (zero to peak pressures up to 32 kPa and single pulse sound exposure levels up to 186 dB re 1µPa(2s. The device was used to examine lethal effects of sound exposure in common sole (Solea solea larvae. Different developmental stages were exposed to various levels and durations of pile-driving sound. The highest cumulative sound exposure level applied was 206 dB re 1µPa(2s, which corresponds to 100 strikes at a distance of 100 m from a typical North Sea pile-driving site. The results showed no statistically significant differences in mortality between exposure and control groups at sound exposure levels which were well above the US interim criteria for non-auditory tissue damage in fish. Although our findings cannot be extrapolated to fish larvae in general, as interspecific differences in vulnerability to sound exposure may occur, they do indicate that previous assumptions and criteria may need to be revised.

Inherited discontinuities and fault kinematics of a multiphase, non-colinear extensional setting: Subsurface observations from the South Flank of the Golfo San Jorge basin, Patagonia

Science.gov (United States)

Paredes, José Matildo; Aguiar, Mariana; Ansa, Andrés; Giordano, Sergio; Ledesma, Mario; Tejada, Silvia

2018-01-01

We use three-dimensional (3D) seismic reflection data to analyze the structural style, fault kinematics and growth fault mechanisms of non-colinear normal fault systems in the South Flank of the Golfo San Jorge basin, central Patagonia. Pre-existing structural fabrics in the basement of the South Flank show NW-SE and NE-SW oriented faults. They control the location and geometry of wedge-shaped half grabens from the "main synrift phase" infilled with Middle Jurassic volcanic-volcaniclastic rocks and lacustrine units of Late Jurassic to Early Cretaceous age. The NE-striking, basement-involved normal faults resulted in the rapid establishment of fault lenght, followed by gradual increasing in displacement, and minor reactivation during subsequent extensional phases; NW-striking normal faults are characterized by fault segments that propagated laterally during the "main rifting phase", being subsequently reactivated during succesive extensional phases. The Aptian-Campanian Chubut Group is a continental succession up to 4 km thick associated to the "second rifting stage", characterized by propagation and linkage of W-E to WNW-ESE fault segments that increase their lenght and displacement in several extensional phases, recognized by detailed measurement of current throw distribution of selected seismic horizons along fault surfaces. Strain is distributed in an array of sub-parallel normal faults oriented normal to the extension direction. A Late Cretaceous-Paleogene (pre-late Eocene) extensional event is characterized by high-angle, NNW-SSE to NNE-SSW grabens coeval with intraplate alkali basaltic volcanism, evidencing clockwise rotation of the stress field following a ∼W-E extension direction. We demonstrate differences in growth fault mechanisms of non-colinear fault populations, and highlight the importance of follow a systematic approach to the analysis of fault geometry and throw distribution in a fault network, in order to understand temporal-spatial variations

Factors driving public tolerance levels and information-seeking behaviour concerning insects in the household environment.

Science.gov (United States)

Schoelitsz, Bruce; Poortvliet, P Marijn; Takken, Willem

2018-06-01

The public's negative attitudes towards household insects drive tolerance for these insects and their control. Tolerance levels are important in integrated pest management (IPM), as are pest knowledge and information. The risk information seeking and processing (RISP) model describes the relationships between personal factors and information-seeking behaviour. We combined IPM and RISP to determine important relationships between factors driving insect tolerance levels and information-seeking behaviour through an online survey and tested whether this model is valid and generally applicable. Relationships between variables from both IPM and RISP models were tested for seven insect species. Tolerance levels were measured with two factors: willingness to pay for pest control and whether insects are tolerated. Willingness to pay for control was positively affected by age, experience, risk perception, insect characteristics, and negative emotions and affected behavioural intention, by influencing information sufficiency and information-seeking behaviour. Tolerability was influenced by perception of insect characteristics and determines whether control measures are taken. It was possible to combine the RISP and IPM models. Relevant driving factors were a person's age, experience, risk perception, negative affective responses, tolerance levels, relevant channel beliefs about online forums, information sufficiency and information-seeking behaviour. There was, however, variation in important factors between different insects. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Comparison of Levelized Cost of Energy of superconducting direct drive generators for a 10 MW offshore wind turbine

DEFF Research Database (Denmark)

Abrahamsen, Asger Bech; Liu, Dong; Magnusson, Niklas

2018-01-01

A method for comparing the Levelized Cost of Energy (LCoE) of different superconducting drive trains is introduced. The properties of a 10 MW MgB$_{2}$ superconducting direct drive generator are presented in terms weight scaled to a turbine with a rotor diameter up of 280 m and the cost break down...

Common sole larvae survive high levels of pile-driving sound in controlled exposure experiments

NARCIS (Netherlands)

Bolle, L.J.; Jong, C.A.F. de; Bierman, S.M.; Beek, P.J.G. van; Keeken, O.A. van; Wessels, P.W.; Damme, C.J.G. van; Winter, H.V.; Haan, D. de; Dekeling, R.P.A.

2012-01-01

In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at

Factors driving public tolerance levels and information-seeking behaviour concerning insects in the household environment

NARCIS (Netherlands)

Schoelitsz, Bruce; Poortvliet, P.M.; Takken, Willem

2018-01-01

BACKGROUND: The public's negative attitudes towards household insects drive tolerance for these insects and their control. Tolerance levels are important in integrated pest management (IPM), as are pest knowledge and information. The risk information seeking and processing (RISP) model describes the

Perturbing an electromagnetically induced transparency in a Λ system using a low-frequency driving field. II. Four-level system

International Nuclear Information System (INIS)

Wilson, E. A.; Manson, N. B.; Wei, C.

2005-01-01

The effect a perturbing field has on an electromagnetically induced transparency within a three-level Λ system is presented. The perturbing field is applied resonant between one of the lower levels of the Λ system and a fourth level. The electromagnetically induced transparency feature is split and this is measured experimentally for both single and bichromatic driving fields. In the single-driving-field case a density matrix treatment is shown to be in reasonable agreement with experiment and in both single and bichromatic cases the structure in the spectrum can be explained using a dressed-state analysis

Hurried driving: Relationship to distress tolerance, driver anger, aggressive and risky driving in college students.

Science.gov (United States)

Beck, Kenneth H; Daughters, Stacey B; Ali, Bina

2013-03-01

Being a hurried driver is associated with a variety of risky driving behaviors, yet the mechanisms underlying this behavior remain unknown. Distress tolerance, defined as an individual's capability to experience and endure negative emotional states, was examined as a predictor of hurried driving among 769 college students. Results indicate that after controlling for age, gender, race, ethnicity, the student's year in school, their grade point average, driving frequency, angry driving, aggressive driving as well as other forms of self-reported risky driving; hurried driving was significantly associated with lower levels of distress tolerance. Hurried drivers also reported greater levels of frustration and impatience with other drivers, suggesting that they have difficulty in withstanding or coping with negative psychological states when driving. Traditional traffic safety campaigns that emphasize enforcement may be less successful with these drivers. The need to develop campaigns that address the affective coping abilities that contribute to this behavioral pattern is discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Exploring Forensic Implications of the Fusion Drive

Directory of Open Access Journals (Sweden)

Shruti Gupta

2014-09-01

Full Text Available This paper explores the forensic implications of Apple's Fusion Drive. The Fusion Drive is an example of auto-tiered storage. It uses a combination of a flash drive and a magnetic drive. Data is moved between the drives automatically to maximize system performance. This is different from traditional caches because data is moved and not simply copied. The research included understanding the drive structure, populating the drive, and then accessing data in a controlled setting to observe data migration strategies. It was observed that all the data is first written to the flash drive with 4 GB of free space always maintained. If data on the magnetic drive is frequently accessed, it is promoted to the flash drive while demoting other information. Data is moved at a block-level and not a file-level. The Fusion Drive didn't alter the timestamps of files with data migration.

Lower level of drink-driving in The Netherlands coincides with increased drug-driving.

NARCIS (Netherlands)

Mathijssen, M.P.M.

2000-01-01

Drink-driving in The Netherlands has dropped significantly since the mid-eighties. In 1983, 12% of car drivers during weekend-nights were over the legal BAC-limit of 0.5 g/l. In the first half of the 1990s, this proportion had dropped to around 4%. In the second half of the 1990s, the proportion of

Dissipative two-level system under strong ac driving: A combination of Floquet and Van Vleck perturbation theory

International Nuclear Information System (INIS)

Hausinger, Johannes; Grifoni, Milena

2010-01-01

We study the dissipative dynamics of a two-level system (TLS) exposed to strong ac driving. By combining Floquet theory with Van Vleck perturbation theory in the TLS tunneling matrix element, we diagonalize the time-dependent Hamiltonian and provide corrections to the renormalized Rabi frequency of the TLS, which are valid for both a biased and unbiased TLS and go beyond the known high-frequency and rotating-wave results. In order to mimic environmental influences on the TLS, we couple the system weakly to a thermal bath and solve analytically the corresponding Floquet-Bloch-Redfield master equation. We give a closed expression for the relaxation and dephasing rates of the TLS and discuss their behavior under variation of the driving amplitude. Further, we examine the robustness of coherent destruction of tunneling (CDT) and driving-induced tunneling oscillations (DITO). We show that also for a moderate driving frequency an almost complete suppression of tunneling can be achieved for short times and demonstrate the sensitiveness of DITO to a change of the external parameters.

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

Science.gov (United States)

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.

Resonance Fluorescence of a Trapped Four-Level Atom with Bichromatic Driving

International Nuclear Information System (INIS)

Bergou, J.; Jakob, M.; Abranyos, Y.

1999-01-01

The resonance fluorescence spectrum of a bichromatically driven four-level atom is polarization dependent. Very narrow lines occur in the incoherent parts of the spectrum for polarization directions which are different from that of the driving fields. The degree of squeezing has a maximum of 56% which should make it easily observable. The second-order correlation function exhibits anti bunching for zero time delay and strong super bunching for certain values of the interaction parameter and time delay. For these parameters resonant two-photon emission takes place in the form of polarization entangled photon pairs. The system can be a novel source of photons in the EPR and/or Bell states. Some experiments will be proposed which make use of this unique source. (Authors)

Effects of chewing gum on driving performance as evaluated by the STISIM driving simulator

OpenAIRE

Yoo, Ingyu; Kim, Eun-Joo; Lee, Joo-Hyun

2015-01-01

[Purpose] The purpose of this study was to determine the effects of chewing gum on driving performance in a driving simulator. [Subjects] In total, 26 young licensed drivers participated. [Methods] The driving scenario was typical of an urban environment: a single-carriageway, two-way road consisting of a mix of curved and straight sections, with considerable levels of traffic, pedestrians, and parked cars. Mean distance driven above the speed limit, lane position, mean distance driven across...

Effectiveness of enforcement levels of speed limit and drink driving laws and associated factors – Exploratory empirical analysis using a bivariate ordered probit model

Directory of Open Access Journals (Sweden)

Behram Wali

2017-06-01

Full Text Available The contemporary traffic safety research comprises little information on quantifying the simultaneous association between drink driving and speeding among fatally injured drivers. Potential correlation between driver's drink driving and speeding behavior poses a substantial methodological concern which needs investigation. This study therefore focused on investigating the simultaneous impact of socioeconomic factors, fatalities, vehicle ownership, health services and highway agency road safety policies on enforcement levels of speed limit and drink driving laws. The effectiveness of enforcement levels of speed limit and drink driving laws has been investigated through development of bivariate ordered probit model using data extricated from WHO's global status report on road safety in 2013. The consistent and intuitive parameter estimates along with statistically significant correlation between response outcomes validates the statistical supremacy of bivariate ordered probit model. The results revealed that fatalities per thousand registered vehicles, hospital beds per hundred thousand population and road safety policies are associated with a likely medium or high effectiveness of enforcement levels of speed limit and drink driving laws, respectively. Also, the model encapsulates the effect of several other agency related variables and socio-economic status on the response outcomes. Marginal effects are reported for analyzing the impact of such factors on intermediate categories of response outcomes. The results of this study are expected to provide necessary insights to elemental enforcement programs. Also, marginal effects of explanatory variables may provide useful directions for formulating effective policy countermeasures for overcoming driver's speeding and drink driving behavior.

In situ mortality experiments with juvenile sea bass (Dicentrarchus labrax in relation to impulsive sound levels caused by pile driving of windmill foundations.

Directory of Open Access Journals (Sweden)

Elisabeth Debusschere

Full Text Available Impact assessments of offshore wind farm installations and operations on the marine fauna are performed in many countries. Yet, only limited quantitative data on the physiological impact of impulsive sounds on (juvenile fishes during pile driving of offshore wind farm foundations are available. Our current knowledge on fish injury and mortality due to pile driving is mainly based on laboratory experiments, in which high-intensity pile driving sounds are generated inside acoustic chambers. To validate these lab results, an in situ field experiment was carried out on board of a pile driving vessel. Juvenile European sea bass (Dicentrarchus labrax of 68 and 115 days post hatching were exposed to pile-driving sounds as close as 45 m from the actual pile driving activity. Fish were exposed to strikes with a sound exposure level between 181 and 188 dB re 1 µPa².s. The number of strikes ranged from 1739 to 3067, resulting in a cumulative sound exposure level between 215 and 222 dB re 1 µPa².s. Control treatments consisted of fish not exposed to pile driving sounds. No differences in immediate mortality were found between exposed and control fish groups. Also no differences were noted in the delayed mortality up to 14 days after exposure between both groups. Our in situ experiments largely confirm the mortality results of the lab experiments found in other studies.

Driving Safety after Spinal Surgery: A Systematic Review.

Science.gov (United States)

Alhammoud, Abduljabbar; Alkhalili, Kenan; Hannallah, Jack; Ibeche, Bashar; Bajammal, Sohail; Baco, Abdul Moeen

2017-04-01

This study aimed to assess driving reaction times (DRTs) after spinal surgery to establish a timeframe for safe resumption of driving by the patient postoperatively. The MEDLINE and Google Scholar databases were analyzed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) Statement for clinical studies that investigated changes in DRTs following cervical and lumbar spinal surgery. Changes in DRTs and patients' clinical presentation, pathology, anatomical level affected, number of spinal levels involved, type of intervention, pain level, and driving skills were assessed. The literature search identified 12 studies that investigated postoperative DRTs. Six studies met the inclusion criteria; five studies assessed changes in DRT after lumbar spine surgery and two studies after cervical spina surgery. The spinal procedures were selective nerve root block, anterior cervical discectomy and fusion, and lumbar fusion and/ordecompression. DRTs exhibited variable responses to spinal surgery and depended on the patients' clinical presentation, spinal level involved, and type of procedure performed. The evidence regarding the patients' ability to resume safe driving after spinal surgery is scarce. Normalization of DRT or a return of DRT to pre-spinal intervention level is a widely accepted indicator for safe driving, with variable levels of statistical significance owing to multiple confounding factors. Considerations of the type of spinal intervention, pain level, opioid consumption, and cognitive function should be factored in the assessment of a patient's ability to safely resume driving.

Modeling human learning involved in car driving

NARCIS (Netherlands)

Wewerinke, P.H.

1994-01-01

In this paper, car driving is considered at the level of human tracking and maneuvering in the context of other traffic. A model analysis revealed the most salient features determining driving performance and safety. Learning car driving is modelled based on a system theoretical approach and based

The impact of continuous driving time and rest time on commercial drivers' driving performance and recovery.

Science.gov (United States)

Wang, Lianzhen; Pei, Yulong

2014-09-01

This real road driving study was conducted to investigate the effects of driving time and rest time on the driving performance and recovery of commercial coach drivers. Thirty-three commercial coach drivers participated in the study, and were divided into three groups according to driving time: (a) 2 h, (b) 3 h, and (c) 4 h. The Stanford Sleepiness Scale (SSS) was used to assess the subjective fatigue level of the drivers. One-way ANOVA was employed to analyze the variation in driving performance. The statistical analysis revealed that driving time had a significant effect on the subjective fatigue and driving performance measures among the three groups. After 2 h of driving, both the subjective fatigue and driving performance measures began to deteriorate. After 4 h of driving, all of the driving performance indicators changed significantly except for depth perception. A certain amount of rest time eliminated the negative effects of fatigue. A 15-minute rest allowed drivers to recover from a two-hour driving task. This needed to be prolonged to 30 min for driving tasks of 3 to 4 h of continuous driving. Drivers' attention, reactions, operating ability, and perceptions are all affected in turn after over 2 h of continuous driving. Drivers should take a certain amount of rest to recover from the fatigue effects before they continue driving. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.

Performance analysis of three-dimensional-triple-level cell and two-dimensional-multi-level cell NAND flash hybrid solid-state drives

Science.gov (United States)

Sakaki, Yukiya; Yamada, Tomoaki; Matsui, Chihiro; Yamaga, Yusuke; Takeuchi, Ken

2018-04-01

In order to improve performance of solid-state drives (SSDs), hybrid SSDs have been proposed. Hybrid SSDs consist of more than two types of NAND flash memories or NAND flash memories and storage-class memories (SCMs). However, the cost of hybrid SSDs adopting SCMs is more expensive than that of NAND flash only SSDs because of the high bit cost of SCMs. This paper proposes unique hybrid SSDs with two-dimensional (2D) horizontal multi-level cell (MLC)/three-dimensional (3D) vertical triple-level cell (TLC) NAND flash memories to achieve higher cost-performance. The 2D-MLC/3D-TLC hybrid SSD achieves up to 31% higher performance than the conventional 2D-MLC/2D-TLC hybrid SSD. The factors of different performance between the proposed hybrid SSD and the conventional hybrid SSD are analyzed by changing its block size, read/write/erase latencies, and write unit of 3D-TLC NAND flash memory, by means of a transaction-level modeling simulator.

Chronotype-dependent circadian rhythmicity of driving safety.

Science.gov (United States)

Del Rio-Bermudez, Carlos; Diaz-Piedra, Carolina; Catena, Andrés; Buela-Casal, Gualberto; Di Stasi, Leandro Luigi

2014-05-01

Among the factors associated with driving safety, sleep-related variables constitute a leading cause of road accidents. Circadian fluctuations of driver's somnolence has been previously linked to road safety. However, the role of chronotype in this relationship has been poorly investigated. Thus, the aim of the present work was to address whether driving performance is influenced by circadian patterns, in turn modulated by the driver's chronotype and the time of day (i.e. synchrony effect). We assessed 47 healthy young adults with specific chronotypes in several simulated driving sessions, both in the morning and in the evening. We collected driving performance data, along with self-reported levels of activation prior to each driving session and other sleep-related variables. Participants drove less safely when testing times took place outside their optimal time of day, as determined by their chronotype and confirmed by self-reported levels of activation. These differences were more pronounced in the morning, when morning types shown a better driving performance. Our results suggest that chronotype plays an important role as a modulator of the relationship between the time of day and driving safety. Therefore, it is necessary to acknowledge this variable in theoretical models of driving behavior, and for the improvement of occupational accidents prevention programs.

Extended driving impairs nocturnal driving performances.

Directory of Open Access Journals (Sweden)

Patricia Sagaspe

Full Text Available Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3-5 am, 1-5 am and 9 pm-5 am on open highway. Fourteen young healthy men (mean age [+/-SD] = 23.4 [+/-1.7] years participated Inappropriate line crossings (ILC in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3-5 am driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05 for the intermediate (1-5 am driving session and by 4.0 (CI, 1.7 to 9.4; P<.001 for the long (9 pm-5 am driving session. Compared to the reference session (9-10 pm, the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001, 15.4 (CI, 4.6 to 51.5; P<.001 and 24.3 (CI, 7.4 to 79.5; P<.001, respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05 and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01. At night, extended driving impairs driving performances and therefore should be limited.

Background Noise Analysis in a Few-Photon-Level Qubit Memory

Science.gov (United States)

Mittiga, Thomas; Kupchak, Connor; Jordaan, Bertus; Namazi, Mehdi; Nolleke, Christian; Figeroa, Eden

2014-05-01

We have developed an Electromagnetically Induced Transparency based polarization qubit memory. The device is composed of a dual-rail probe field polarization setup colinear with an intense control field to store and retrieve any arbitrary polarization state by addressing a Λ-type energy level scheme in a 87Rb vapor cell. To achieve a signal-to-background ratio at the few photon level sufficient for polarization tomography of the retrieved state, the intense control field is filtered out through an etalon filtrating system. We have developed an analytical model predicting the influence of the signal-to-background ratio on the fidelities and compared it to experimental data. Experimentally measured global fidelities have been found to follow closely the theoretical prediction as signal-to-background decreases. These results suggest the plausibility of employing room temperature memories to store photonic qubits at the single photon level and for future applications in long distance quantum communication schemes.

Effects of chewing gum on driving performance as evaluated by the STISIM driving simulator.

Science.gov (United States)

Yoo, Ingyu; Kim, Eun-Joo; Lee, Joo-Hyun

2015-06-01

[Purpose] The purpose of this study was to determine the effects of chewing gum on driving performance in a driving simulator. [Subjects] In total, 26 young licensed drivers participated. [Methods] The driving scenario was typical of an urban environment: a single-carriageway, two-way road consisting of a mix of curved and straight sections, with considerable levels of traffic, pedestrians, and parked cars. Mean distance driven above the speed limit, lane position, mean distance driven across the center line, and mean distance driven off the road were used as estimates of brake, accelerator, and steering control. The results were compared with those of a non-chewing gum control condition. [Results] The driving performance while chewing gum was significantly better: the mean distance driven above the speed limit was 26.61% shorter, and the mean distance driven off the road was 31.99% shorter. Lane position and mean distance driven across the center line did not differ significantly between the two conditions. [Conclusion] Chewing gum appears to enhance driving performance during a sustained attention driving task.

Instant Google Drive starter

CERN Document Server

Procopio, Mike

2013-01-01

This book is a Starter which teaches you how to use Google Drive practically. This book is perfect for people of all skill levels who want to enjoy the benefits of using Google Drive to safely store their files online and in the cloud. It's also great for anyone looking to learn more about cloud computing in general. Readers are expected to have an Internet connection and basic knowledge of using the internet.

Low-level feedback control for the phase regulation of CLIC Drive Beam Klystrons

CERN Document Server

AUTHOR|(SzGeCERN)752526

2015-01-01

The requirement of luminosity loss below 1% raises tight tolerances for the phase and power stability of the CLIC drive beam (DB) klystrons and consequently for the high voltage pulse ripple of the modulators. A low-level RF (LLRF) feedback system needs to be developed and combined with the modulator in order to guarantee the phase and amplitude tolerances. To this aim, three feedback control strategies were investigated, i) Proportional Integral (PI) controller, ii) Linear Quadratic Integral Regulator (LQI) and iii) Model Predictive Controller (MPC). The klystron, as well as the incident phase noise were modelled and used for the design and evaluation of the controllers. First simulation results are presented along with future steps and directions.

Efficiency optimized control of medium-size induction motor drives

DEFF Research Database (Denmark)

Abrahamsen, F.; Blaabjerg, Frede; Pedersen, John Kim

2000-01-01

The efficiency of a variable speed induction motor drive can be optimized by adaption of the motor flux level to the load torque. In small drives (<10 kW) this can be done without considering the relatively small converter losses, but for medium-size drives (10-1000 kW) the losses can not be disr......The efficiency of a variable speed induction motor drive can be optimized by adaption of the motor flux level to the load torque. In small drives (... not be disregarded without further analysis. The importance of the converter losses on efficiency optimization in medium-size drives is analyzed in this paper. Based on the experiments with a 90 kW drive it is found that it is not critical if the converter losses are neglected in the control, except...... that the robustness towards load disturbances may unnecessarily be reduced. Both displacement power factor and model-based efficiency optimizing control methods perform well in medium-size drives. The last strategy is also tested on a 22 kW drive with good results....

Impaired driving from medical conditions: A 70-year-old man trying to decide if he should continue driving

Science.gov (United States)

Rizzo, Matthew

2012-01-01

Some medical disorders can impair performance, increasing the risk of driving safety errors that can lead to vehicle crashes. The causal pathway often involves a concatenation of factors or events, some of which can be prevented or controlled. Effective interventions can operate before, during, or after a crash occurs at the levels of driver capacity, vehicle and road design, and public policy. A variety of systemic, neurological, psychiatric, and developmental disorders put drivers at potential increased risk of a car crash in the short or long term. Medical diagnosis and age alone are usually insufficient criteria for determining fitness to drive. Strategies are needed for determining what types and levels of reduced function provide a threshold for disqualification in drivers with medical disorders. Evidence of decreased mileage, self-restriction to driving in certain situations, collisions, moving violations, aggressive driving, sleepiness, alcohol abuse, metabolic disorders, and multiple medications may trigger considerations of driver safety. A general framework for evaluating driver fitness relies on a functional evaluation of multiple domains (cognitive, motor, perceptual, and psychiatric) that are important for safe driving and can be applied across many disorders, including conditions that have rarely been studied with respect to driving, and in patients with multiple conditions and medications. Neurocognitive tests, driving simulation, and road tests provide complementary sources of evidence to evaluate driver safety. No single test is sufficient to determine who should drive and who should not. PMID:21364126

Impaired driving from medical conditions: a 70-year-old man trying to decide if he should continue driving.

Science.gov (United States)

Rizzo, Matthew

2011-03-09

Some medical disorders can impair performance, increasing the risk of driving safety errors that can lead to vehicle crashes. The causal pathway often involves a concatenation of factors or events, some of which can be prevented or controlled. Effective interventions can operate before, during, or after a crash occurs at the levels of driver capacity, vehicle and road design, and public policy. A variety of systemic, neurological, psychiatric, and developmental disorders put drivers at potential increased risk of a car crash in the short or long term. Medical diagnosis and age alone are usually insufficient criteria for determining fitness to drive. Strategies are needed for determining what types and levels of reduced function provide a threshold for disqualification in drivers with medical disorders. Evidence of decreased mileage, self-restriction to driving in certain situations, collisions, moving violations, aggressive driving, sleepiness, alcohol abuse, metabolic disorders, and multiple medications may trigger considerations of driver safety. A general framework for evaluating driver fitness relies on a functional evaluation of multiple domains (cognitive, motor, perceptual, and psychiatric) that are important for safe driving and can be applied across many disorders, including conditions that have rarely been studied with respect to driving, and in patients with multiple conditions and medications. Neurocognitive tests, driving simulation, and road tests provide complementary sources of evidence to evaluate driver safety. No single test is sufficient to determine who should drive and who should not.

Universal Drive Train Facility

Data.gov (United States)

Federal Laboratory Consortium — This vehicle drive train research facility is capable of evaluating helicopter and ground vehicle power transmission technologies in a system level environment. The...

Driving performance at lateral system limits during partially automated driving.

Science.gov (United States)

Naujoks, Frederik; Purucker, Christian; Wiedemann, Katharina; Neukum, Alexandra; Wolter, Stefan; Steiger, Reid

2017-11-01

This study investigated driver performance during system limits of partially automated driving. Using a motion-based driving simulator, drivers encountered different situations in which a partially automated vehicle could no longer safely keep the lateral guidance. Drivers were distracted by a non-driving related task on a touch display or driving without an additional secondary task. While driving in partially automated mode drivers could either take their hands off the steering wheel for only a short period of time (10s, so-called 'Hands-on' variant) or for an extended period of time (120s, so-called 'Hands-off' variant). When the system limit was reached (e.g., when entering a work zone with temporary lines), the lateral vehicle control by the automation was suddenly discontinued and a take-over request was issued to the drivers. Regardless of the hands-off interval and the availability of a secondary task, all drivers managed the transition to manual driving safely. No lane exceedances were observed and the situations were rated as 'harmless' by the drivers. The lack of difference between the hands-off intervals can be partly attributed to the fact that most of the drivers kept contact to the steering wheel, even in the hands-off condition. Although all drivers were able to control the system limits, most of them could not explain why exactly the take-over request was issued. The average helpfulness of the take-over request was rated on an intermediate level. Consequently, providing drivers with information about the reason for a system limit can be recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

Glaucoma and Driving: On-Road Driving Characteristics

Science.gov (United States)

Wood, Joanne M.; Black, Alex A.; Mallon, Kerry; Thomas, Ravi; Owsley, Cynthia

2016-01-01

Purpose To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment. Methods Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years) with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB) and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years). On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire. Results Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability. Conclusions Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness. PMID:27472221

Glaucoma and Driving: On-Road Driving Characteristics.

Directory of Open Access Journals (Sweden)

Joanne M Wood

Full Text Available To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment.Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years. On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire.Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability.Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness.

Glaucoma and Driving: On-Road Driving Characteristics.

Science.gov (United States)

Wood, Joanne M; Black, Alex A; Mallon, Kerry; Thomas, Ravi; Owsley, Cynthia

2016-01-01

To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment. Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years) with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB) and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years). On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire. Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability. Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness.

Can We Study Autonomous Driving Comfort in Moving-Base Driving Simulators? A Validation Study.

Science.gov (United States)

Bellem, Hanna; Klüver, Malte; Schrauf, Michael; Schöner, Hans-Peter; Hecht, Heiko; Krems, Josef F

2017-05-01

To lay the basis of studying autonomous driving comfort using driving simulators, we assessed the behavioral validity of two moving-base simulator configurations by contrasting them with a test-track setting. With increasing level of automation, driving comfort becomes increasingly important. Simulators provide a safe environment to study perceived comfort in autonomous driving. To date, however, no studies were conducted in relation to comfort in autonomous driving to determine the extent to which results from simulator studies can be transferred to on-road driving conditions. Participants ( N = 72) experienced six differently parameterized lane-change and deceleration maneuvers and subsequently rated the comfort of each scenario. One group of participants experienced the maneuvers on a test-track setting, whereas two other groups experienced them in one of two moving-base simulator configurations. We could demonstrate relative and absolute validity for one of the two simulator configurations. Subsequent analyses revealed that the validity of the simulator highly depends on the parameterization of the motion system. Moving-base simulation can be a useful research tool to study driving comfort in autonomous vehicles. However, our results point at a preference for subunity scaling factors for both lateral and longitudinal motion cues, which might be explained by an underestimation of speed in virtual environments. In line with previous studies, we recommend lateral- and longitudinal-motion scaling factors of approximately 50% to 60% in order to obtain valid results for both active and passive driving tasks.

Dominant role of winds near Sri Lanka in driving seasonal sea level variations along the west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Suresh, I.; Vialard, J.; Izumo, T.; Lengaigne, M.; Han, W.; Mc; Muraleedharan, P.M.

version: Geophys. Res. Lett.: 43(13); 2016; 7028-7035 Dominant role of winds near Sri Lanka in driving seasonal sea-level variations along the west coast of India I. Suresh1, J. Vialard2, T. Izumo2,3, M. Lengaigne,2,3, W. Han4, J. McCreary5, P... as manifested both in sea level and surface circulation of the North Indian Ocean (NIO) [e.g., Schott and McCreary, 2001]. The sea level along the west coast of India (WCI), in particular, is dominated by the seasonal cycle. Figure 1a, which shows...

Modeling an electric motor in 1-D

Science.gov (United States)

Butler, Thomas G.

1991-01-01

Quite often the dynamicist will be faced with having an electric drive motor as a link in the elastic path of a structure such that the motor's characteristics must be taken into account to properly represent the dynamics of the primary structure. He does not want to model it so accurately that he could get detailed stress and displacements in the motor proper, but just sufficiently to represent its inertia loading and elastic behavior from its mounting bolts to its drive coupling. Described here is how the rotor and stator of such a motor can be adequately modeled as a colinear pair of beams.

Electric-drive tractability indicator integrated in hybrid electric vehicle tachometer

Science.gov (United States)

Tamai, Goro; Zhou, Jing; Weslati, Feisel

2014-09-02

An indicator, system and method of indicating electric drive usability in a hybrid electric vehicle. A tachometer is used that includes a display having an all-electric drive portion and a hybrid drive portion. The all-electric drive portion and the hybrid drive portion share a first boundary which indicates a minimum electric drive usability and a beginning of hybrid drive operation of the vehicle. The indicated level of electric drive usability is derived from at least one of a percent battery discharge, a percent maximum torque provided by the electric drive, and a percent electric drive to hybrid drive operating cost for the hybrid electric vehicle.

Designing for enhancing situational awareness of semi-autonomous driving vehicles

NARCIS (Netherlands)

Wang, C.; Steeghs, S.; Chakraborty, D.; Gorle, A.; Dey, D.; Van De Star, S.; Sudhakaran, A.; Terken, J.M.B.; Hu, J.

2017-01-01

Autonomous driving technology is evolving quickly, and self-driving cars are fast becoming a reality. In the level 2 autonomous driving stage, the system will take full control of the vehicle. The driver must monitor the driving and be prepared to immediately intervene at any time if the automated

Decision tool for clients with medical issues: a framework for identifying driving risk and potential to return to driving.

Science.gov (United States)

Dickerson, Anne E; Bédard, Michel

2014-04-01

This paper offers occupational therapy generalists and specialists a new framework by which to consider clinical evaluation data and an older adult's driving risk and potential to resume this previously learned skill. Based on Michon's model describing the hierarchy of driving levels, clinical questions identify the factors that may affect a client's fitness to drive. The first part is intended to support clinical judgment of whether a client needs a driving evaluation by a driver rehabilitation specialist. The second part offers a framework to organize clinical data that are already known and determine what other evaluation information is justified and necessary to make a driving recommendation. Methods and rational for use are discussed.

Identifying Method of Drunk Driving Based on Driving Behavior

Directory of Open Access Journals (Sweden)

Xiaohua Zhao

2011-05-01

Full Text Available Drunk driving is one of the leading causes contributing to traffic crashes. There are numerous issues that need to be resolved with the current method of identifying drunk driving. Driving behavior, with the characteristic of real-time, was extensively researched to identify impaired driving behaviors. In this paper, the drives with BACs above 0.05% were defined as drunk driving state. A detailed comparison was made between normal driving and drunk driving. The experiment in driving simulator was designed to collect the driving performance data of the groups. According to the characteristics analysis for the effect of alcohol on driving performance, seven significant indicators were extracted and the drunk driving was identified by the Fisher Discriminant Method. The discriminant function demonstrated a high accuracy of classification. The optimal critical score to differentiate normal from drinking state was found to be 0. The evaluation result verifies the accuracy of classification method.

Study of the Effects of Alcohol on Drivers and Driving Performance on Straight Road

Directory of Open Access Journals (Sweden)

Xiaohua Zhao

2014-01-01

Full Text Available Drinking driving is responsible for a high proportion of traffic accidents. To study the effects of alcohol on drivers and driving performance, 25 drivers’ subjective feelings and driving performance data in different blood-alcohol concentration (BAC levels were collected with simulated driving experiment. The investigation results revealed that alcohol affected drivers in many aspects, including attitude, judgment, vigilance, perception, reaction, and controlling. The analysis of accident rate showed that higher BAC level would lead to higher accident rate. The statistical analysis results of driving performance indicated that average speed, speed standard deviation, and lane position standard deviation were significantly higher under the influence of alcohol. They also had a statistically significant linear trend as the function of BAC level. The discrimination of drinking driving based on driving performance was performed with Fisher discrimination method. The results showed that drinking driving with higher BAC level was easier to discriminate from normal driving. Also, the results indicated that the three significant indicators on straight roadway could be used in the discrimination of drinking driving state. The conclusions can provide references for the study of drinking driving and the identification of driving state and then contribute to traffic safety.

Driving styles and their associations with personality and motivation.

Science.gov (United States)

Taubman-Ben-Ari, Orit; Yehiel, Dalia

2012-03-01

The associations between driving styles and the Big-Five personality factors and perceived costs and benefits of driving were examined in order to obtain a more comprehensive understanding of driving styles. Questionnaires tapping driving style, personality traits, motivations for driving, and background variables were completed by 320 drivers (150 men and 170 women). The results show that each driving style is associated with a unique set of sociodemographic, personality, and motivational factors. The reckless and angry styles were both endorsed more by men than women, by younger drivers, and by those displaying higher levels of Extroversion and thrill seeking, and lower levels of Agreeableness and Conscientiousness. However, whereas the reckless style was also predicted by the perceived costs of driving-related distress, as well as higher perceived risk to life among those with higher education, the angry style was also predicted by perceptions of both control and annoyance among more educated drivers. The anxious style was endorsed more by women, and by drivers lower on Conscientiousness and higher on Neuroticism. Individuals reporting this style regard driving as a cause of distress and annoyance, and, depending on their level of education, perceive it as entailing more risk to life and as a potential damage to their self-image (higher education), or as providing more opportunities for impression management (lower education). The careful driving style was endorsed more by women, and associated with higher Agreeableness, Conscientiousness, and Openness, along with higher pleasure (especially among younger drivers), but lower thrill seeking and worries about damage to self-esteem. The discussion focuses on the importance of looking at driving styles and their predictors holistically in order to design practical interventions suited to different profiles of drivers. Copyright © 2011 Elsevier Ltd. All rights reserved.

[Role of some psycho-physiological factors on driving safety].

Science.gov (United States)

Bergomi, M; Vivoli, G; Rovesti, S; Bussetti, P; Ferrari, A; Vivoli, R

2010-01-01

Within a research project on the role played by human factors on road accidents, the aim of the present study is to evaluate, in young adults, the relationships between driver behaviour and personality factors as well as to assess the neuroendocrine correlates of psychological and behavioural factors investigated. Another aim is to estimate in what measure the performance levels are affected by demographic, psychological and chronobiological variables. It has been found a positive relation between highway code violations, extroversion trait of personality and Sensation Seeking scores, so confirming that this component of personality can affect risky behaviour. Furthermore the subjects more oriented to morningness chronotype were found to be prone to adopt safe driving behaviour. Regarding the relations of the neuroendocrine parameters and driving behaviour a positive correlation was observed between dopamine levels and frequency of driving violations while a negative relationship was found between adrenaline levels and frequency of driving errors. In conclusion the identification of psycho-physiological variables related to driving risky behaviour might be a useful instrument to design traffic safety programs tailored to high risk subjects.

Effectiveness of Variable Message Signs on Driving Behavior Based on a Driving Simulation Experiment

Directory of Open Access Journals (Sweden)

Xuedong Yan

2014-01-01

Full Text Available Variable message signs (VMSs, as one of the important ITS devices, provide real-time traffic information of road network to drivers in order to improve route choice and relieve the traffic congestion. In this study, the effectiveness of VMS on driving behavior was tested based on a driving simulation experiment. A road network with three levels of VMS location to route-diverging intersection and three types of VMS information format was designed in a high fidelity driving simulator platform. Fifty-two subjects who were classified by driver age, gender, and vocation successfully completed this experiment. The experimental results showed that driver characteristics, VMS location, and information format profoundly influence driving behaviors. Based on the research findings, it is suggested that VMS would be positioned between 150 m and 200 m upstream of the diverging point to balance the VMS effects on traffic safety and operation and the graphic information VMS format is better than the format with text massage only.

Introducing a multivariate model for predicting driving performance: the role of driving anger and personal characteristics.

Science.gov (United States)

Roidl, Ernst; Siebert, Felix Wilhelm; Oehl, Michael; Höger, Rainer

2013-12-01

Maladaptive driving is an important source of self-inflicted accidents and this driving style could include high speeds, speeding violations, and poor lateral control of the vehicle. The literature suggests that certain groups of drivers, such as novice drivers, males, highly motivated drivers, and those who frequently experience anger in traffic, tend to exhibit more maladaptive driving patterns compared to other drivers. Remarkably, no coherent framework is currently available to describe the relationships and distinct influences of these factors. We conducted two studies with the aim of creating a multivariate model that combines the aforementioned factors, describes their relationships, and predicts driving performance more precisely. The studies employed different techniques to elicit emotion and different tracks designed to explore the driving behaviors of participants in potentially anger-provoking situations. Study 1 induced emotions with short film clips. Study 2 confronted the participants with potentially anger-inducing traffic situations during the simulated drive. In both studies, participants who experienced high levels of anger drove faster and exhibited greater longitudinal and lateral acceleration. Furthermore, multiple linear regressions and path-models revealed that highly motivated male drivers displayed the same behavior independent of their emotional state. The results indicate that anger and specific risk characteristics lead to maladaptive changes in important driving parameters and that drivers with these specific risk factors are prone to experience more anger while driving, which further worsens their driving performance. Driver trainings and anger management courses will profit from these findings because they help to improve the validity of assessments of anger related driving behavior. © 2013.

Self-rated driving and driving safety in older adults.

Science.gov (United States)

Ross, Lesley A; Dodson, Joan E; Edwards, Jerri D; Ackerman, Michelle L; Ball, Karlene

2012-09-01

Many U.S. states rely on older adults to self-regulate their driving and determine when driving is no longer a safe option. However, the relationship of older adults' self-rated driving in terms of actual driving competency outcomes is unclear. The current study investigates self-rated driving in terms of (1) systematic differences between older adults with high (good/excellent) versus low (poor/fair/average) self-ratings, and (2) the predictive nature of self-rated driving to adverse driving outcomes in older adults (n=350; mean age 73.9, SD=5.25, range 65-91). Adverse driving outcomes included self-reported incidences of (1) being pulled over by the police, (2) receiving a citation, (3) receiving a recommendation to cease or limit driving, (4) crashes, and (5) state-reported crashes. Results found that older drivers with low self-ratings reported more medical conditions, less driving frequency, and had been given more suggestions to stop/limit their driving; there were no other significant differences between low and high self-raters. Logistic regression revealed older drivers were more likely to have a state-reported crash and receive a suggestion to stop or limit driving. Men were more likely to report all adverse driving outcomes except for receiving a suggestion to stop or limit driving. Regarding self-rated driving, older adults with high ratings were 66% less likely (OR=0.34, 95% CI=0.14-0.85) to have received suggestions to limit or stop driving after accounting for demographics, health and driving frequency. Self-ratings were not predictive of other driving outcomes (being pulled over by the police, receiving a citation, self-reported crashes, or state-reported crashes, ps>0.05). Most older drivers (85.14%) rated themselves as either good or excellent drivers regardless of their actual previous citation or crash rates. Self-rated driving is likely not related to actual driving proficiency as indicated by previous crash involvement in older adults

Comparing the self-assessed and examiner-assessed driving skills of Japanese driving school students

Directory of Open Access Journals (Sweden)

Hiroshi Nakai

2012-03-01

A sample of Japanese driving test candidates (n=2021 completed a self-assessment using a 5-point scale applied to 19 items. The candidates completed the assessment shortly after passing their practical driving test conducted at a driving school. Their performance was also assessed by an examiner who used the same scale. The comparison between self-assessment and examiner-assessment revealed that around 40% of Japanese driving school students made a realistic assessment of their skills. With regard to the gender differences, although males displayed higher levels of overconfidence than females did, the differences were not as large as earlier studies with questionnaires had suggested. Furthermore, the effect of age on the accuracy of novice drivers' skill assessment was found to be relatively small. Our findings, which are based on a comparison of subjective assessments of driving skills between examiners and novices, instead of a questionable method which relies on a comparison with a hypothetical average driver, suggest that the majority of candidates in fact do not overrate their own skills. These results were discussed from the viewpoint of the driver education system and compared to other European research using the same framework.

The Drive-Wise Project: Driving Simulator Training increases real driving performance in healthy older drivers

Directory of Open Access Journals (Sweden)

Gianclaudio eCasutt

2014-05-01

Full Text Available Background: Age-related cognitive decline is often associated with unsafe driving behavior. We hypothesized that 10 active training sessions in a driving simulator increase cognitive and on-road driving performance. In addition, driving simulator training should outperform cognitive training.Methods: Ninety-one healthy active drivers (62 – 87 years were randomly assigned to either (1 a driving simulator training group, (2 an attention training group (vigilance and selective attention, or (3 a control group. The main outcome variables were on-road driving and cognitive performance. Seventy-seven participants (85% completed the training and were included in the analyses. Training gains were analyzed using a multiple regression analysis with planned comparisons.Results: The driving simulator training group showed an improvement in on-road driving performance compared to the attention training group. In addition, both training groups increased cognitive performance compared to the control group. Conclusion: Driving simulator training offers the potential to enhance driving skills in older drivers. Compared to the attention training, the simulator training seems to be a more powerful program for increasing older drivers’ safety on the road.

Electrical drives for direct drive renewable energy systems

CERN Document Server

Mueller, Markus

2013-01-01

Wind turbine gearboxes present major reliability issues, leading to great interest in the current development of gearless direct-drive wind energy systems. Offering high reliability, high efficiency and low maintenance, developments in these direct-drive systems point the way to the next generation of wind power, and Electrical drives for direct drive renewable energy systems is an authoritative guide to their design, development and operation. Part one outlines electrical drive technology, beginning with an overview of electrical generators for direct drive systems. Principles of electrical design for permanent magnet generators are discussed, followed by electrical, thermal and structural generator design and systems integration. A review of power electronic converter technology and power electronic converter systems for direct drive renewable energy applications is then conducted. Part two then focuses on wind and marine applications, beginning with a commercial overview of wind turbine drive systems and a...

Self-rated Driving and Driving Safety in Older Adults

OpenAIRE

Ross, Lesley A.; Dodson, Joan; Edwards, Jerri D.; Ackerman, Michelle L.; Ball, Karlene

2012-01-01

Many U.S. states rely on older adults to self-regulate their driving and determine when driving is no longer a safe option. However, the relationship of older adults’ self-rated driving in terms of actual driving competency outcomes is unclear. The current study investigates self-rated driving in terms of (1) systematic differences between older adults with high (good/excellent) versus low (poor/fair/average) self-ratings, and (2) the predictive nature of self-rated driving to adverse driving...

Gender differences in psychosocial predictors of texting while driving.

Science.gov (United States)

Struckman-Johnson, Cindy; Gaster, Samuel; Struckman-Johnson, Dave; Johnson, Melissa; May-Shinagle, Gabby

2015-01-01

A sample of 158 male and 357 female college students at a midwestern university participated in an on-line study of psychosocial motives for texting while driving. Men and women did not differ in self-reported ratings of how often they texted while driving. However, more women sent texts of less than a sentence while more men sent texts of 1-5 sentences. More women than men said they would quit texting while driving due to police warnings, receiving information about texting dangers, being shown graphic pictures of texting accidents, and being in a car accident. A hierarchical regression for men's data revealed that lower levels of feeling distracted by texting while driving (20% of the variance), higher levels of cell phone dependence (11.5% of the variance), risky behavioral tendencies (6.5% of the variance) and impulsivity (2.3%) of the variance) were significantly associated with more texting while driving (total model variance=42%). A separate regression for women revealed that higher levels of cell phone dependence (10.4% of the variance), risky behavioral tendencies (9.9% of the variance), texting distractibility (6.2%), crash risk estimates (2.2% of the variance) and driving confidence (1.3% of the variance) were significantly associated with more texting while driving (total model variance=31%.) Friendship potential and need for intimacy were not related to men's or women's texting while driving. Implications of the results for gender-specific prevention strategies are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cognitive maps influence over driving strategies in Russia: analyzing Driving Anger Expression Inventory (DAX and Dula Dangerous Driving Index (DDDI factors

Directory of Open Access Journals (Sweden)

Chetverikova A.I.

2017-12-01

Full Text Available This article summarizes our investigation of drivers cognitive maps and its influence over their behavior. 182 subjects participated in our research, i.e. 97 professional drivers, 85 car enthusiasts, 156 men and 26 women, 20—66 years old, mileage about 3—150 thousands kilometers per year. Questionnaire “Dula Dangerous Driving Index” was used on Russian subjects for the first time ever. Our results show that subjects’ need for get their rocks off when they are angered (or suspicious, or failed to trust the world around and aggressive behavior during driving are correlated. Most drivers feel emotional tension during driving and use some self-regulation techniques to decrease the tension stabilize their emotional state. The following factors were found to correlate with one’s aggressive behavior on the road: feeling suspicious of world/self/others, low level of self-acceptance, external locus of control.

Impact Of Real-World Driving Characteristics On Vehicular Emissions

OpenAIRE

Nesamani, K S; Subramanian, K. P.

2005-01-01

With increase in traffic volume and change in travel related characteristics, vehicular emissions and energy consumption have increased significantly since two decades in India. Current models are not capable of estimating vehicular emissions accurately due to inadequate representation of real-world driving. The focus of this paper is to understand the level of Indian Driving cycle (IDC) in representing the real-world driving and to assess the impact of real-world driving on vehicular emissio...

Risky driving behavior and road traffic crashes among young Asian Australian drivers: findings from the DRIVE study.

Science.gov (United States)

Boufous, Soufiane; Ivers, Rebecca; Senserrick, Teresa; Norton, Robyn; Stevenson, Mark; Chen, Huei-Yang; Lam, Lawrence T

2010-06-01

To examine differences in risky driving behavior and likelihood of traffic crash according to the country of birth of recently licensed young drivers. The groups examined include those born in Australia, those born in Asia, and those born in other countries. The DRIVE study is a prospective cohort study of drivers aged 17-24 years holding their first-year provisional driver license in New South Wales, Australia. Information obtained from 20,822 participants who completed a baseline questionnaire was linked to police-reported traffic crashes. Self-reported risky driving behaviors and police-reported traffic crashes in young drivers. Young drivers who were born in Asian countries were less likely to report engaging in risky driving behaviors than their Australian-born counterparts. The proportion of participants reporting a high level of risky driving was 31.5 percent (95% confidence intervale [CI], 30.8-32.1) among Australian-born drivers compared to 25.6 percent (95% CI, 23.1-28.2) among Asian-born drivers and 30.4 percent (95% CI, 28.4-32.5) among those born in other regions. Asian-born participants had half the risk of a crash as a driver than their Australian-born counterparts (relative risk [RR] 0.55; 95% CI, 0.41-0.75) after adjusting for a number of demographic factors and driving and risk-taking behaviors. The comparative risk was even lower among those aged 17 years (RR 0.29; 95% CI, 0.29-0.75). Risk estimates for people born in other regions did not differ to those for Australian-born respondents. The study highlights the lower level of risky driving and significantly reduced crash risk for Australian drivers born in Asian countries relative to those born locally. Further research is needed to examine factors underlying this reduced risk and the impact of the length of residence in the host country.

Assessing the Driver's Current Level of Working Memory Load with High Density Functional Near-infrared Spectroscopy: A Realistic Driving Simulator Study.

Science.gov (United States)

Unni, Anirudh; Ihme, Klas; Jipp, Meike; Rieger, Jochem W

2017-01-01

Cognitive overload or underload results in a decrease in human performance which may result in fatal incidents while driving. We envision that driver assistive systems which adapt their functionality to the driver's cognitive state could be a promising approach to reduce road accidents due to human errors. This research attempts to predict variations of cognitive working memory load levels in a natural driving scenario with multiple parallel tasks and to reveal predictive brain areas. We used a modified version of the n-back task to induce five different working memory load levels (from 0-back up to 4-back) forcing the participants to continuously update, memorize, and recall the previous 'n' speed sequences and adjust their speed accordingly while they drove for approximately 60 min on a highway with concurrent traffic in a virtual reality driving simulator. We measured brain activation using multichannel whole head, high density functional near-infrared spectroscopy (fNIRS) and predicted working memory load level from the fNIRS data by combining multivariate lasso regression and cross-validation. This allowed us to predict variations in working memory load in a continuous time-resolved manner with mean Pearson correlations between induced and predicted working memory load over 15 participants of 0.61 [standard error (SE) 0.04] and a maximum of 0.8. Restricting the analysis to prefrontal sensors placed over the forehead reduced the mean correlation to 0.38 (SE 0.04), indicating additional information gained through whole head coverage. Moreover, working memory load predictions derived from peripheral heart rate parameters achieved much lower correlations (mean 0.21, SE 0.1). Importantly, whole head fNIRS sampling revealed increasing brain activation in bilateral inferior frontal and bilateral temporo-occipital brain areas with increasing working memory load levels suggesting that these areas are specifically involved in workload-related processing.

Risk factors for adverse driving outcomes in Dutch adults with ADHD and controls.

Science.gov (United States)

Bron, Tannetje I; Bijlenga, Denise; Breuk, Minda; Michielsen, Marieke; Beekman, Aartjan T F; Kooij, J J Sandra

2018-02-01

To identify risk factors for adverse driving outcomes and unsafe driving among adults with and without ADHD in a Dutch sample. In this cross-sectional study, validated self-report questionnaires were used to compare driving history and current driving behavior between 330 adults diagnosed with ADHD and 330 controls. Adults with ADHD had significantly more adverse driving outcomes when compared to controls. Having an ADHD diagnosis significantly increased the odds for having had 3 or more vehicular crashes (OR = 2.72; p = .001). Driving frequency, male gender, age, high anxiety levels, high hostility levels, and alcohol use all significantly influenced the odds for unsafe driving behavior, for having had 12 or more traffic citations, and/or for having had 3 or more vehicular crashes. Alcohol use, and high levels of anxiety and hostility are highly prevalent among adults with ADHD, and they mediate the risk for negative driving outcomes in this group. Copyright © 2017 Elsevier Ltd. All rights reserved.

Factors affecting return to driving post-stroke.

LENUS (Irish Health Repository)

Tan, K M

2012-02-01

BACKGROUND: Stroke can affect a person\\'s ability to drive, an important means of transportation in the developed world. AIMS: To determine percentage of patients and factors associated with return to driving post-stroke in a service with emphasis on driver assessment. METHODS: Retrospective study of patients discharged from the Stroke Service of our 470-bed teaching hospital from 1998 to 2002. RESULTS: Of 72 drivers pre-stroke, 54% recalled a driving assessment and 68% returned to driving. Younger patients (58.6 +\\/- 12.0 vs. 66.5 +\\/- 10.5, p = 0.008) with lower Modified Rankin Score (median 1 vs. 2, p = 0.0001) and normal cognition (55 vs. 43%, p = 0.45) were more likely to resume driving. More patients who were assessed returned to driving than those who were not (74 vs. 61%, p = 0.31). CONCLUSIONS: A relatively high level of return to driving can be achieved post-stroke with a pro-active approach to driver assessment and rehabilitation. A structured assessment and referral programme should be offered where appropriate.

Drink-driving convictions and the effect of lowering the BAC levels

DEFF Research Database (Denmark)

Christoffersen, Mogens

.g. disadvantages during adolescence, severe psychological problems, prior criminal history, living in rural vs. metropolitan area, and their present social position, e.g. educational background). In order to evaluate the effect of changed legislation on the incidence of first-time drink-driving convictions among...

Classifying Secondary Task Driving Safety Using Method of F-ANP

Directory of Open Access Journals (Sweden)

Lisheng Jin

2015-02-01

Full Text Available This study was designed to build an evaluation system for secondary task driving safety by using method of Fuzzy Analytic Network Process (F-ANP. Forty drivers completed driving on driving simulator while interacting with or without a secondary task. Measures of fixations, saccades, and vehicle running status were analyzed. According to five experts' opinions, a hierarchical model for secondary task driving safety evaluation was built. The hierarchical model was divided into three levels: goal, assessment dimension, and criteria. Seven indexes make up the level of criteria, and the assessment dimension includes two clusters: vehicle control risk and driver eye movement risk. By method of F-ANP, the priorities of the criteria and the subcriteria were determined. Furthermore, to rank the driving safety, an approach based on the principle of maximum membership degree was adopted. At last, a case study of secondary task driving safety evaluation by forty drivers using the proposed method was done. The results indicated that the application of the proposed method is practically feasible and adoptable for secondary task driving safety evaluation.

Age differences in the takeover of vehicle control and engagement in non-driving-related activities in simulated driving with conditional automation.

Science.gov (United States)

Clark, Hallie; Feng, Jing

2017-09-01

High-level vehicle automation has been proposed as a valuable means to enhance the mobility of older drivers, as older drivers experience age-related declines in many cognitive functions that are vital for safe driving. Recent research attempted to examine age differences in how engagement in non-driving-related activities impact driving performance, by instructing drivers to engage in mandatory pre-designed activities. While the mandatory engagement method allows a precise control of the timing and mental workload of the non-driving-related activities, it is different from how a driver would naturally engage in these activities. This study allowed younger (age 18-35, mean age=19.9years) and older drivers (age 62-81, mean age=70.4years) to freely decide when and how to engage in voluntarily chosen non-driving-related activities during simulated driving with conditional automation. We coded video recordings of participants' engagement in non-driving-related activities. We examined the effect of age, level of activity-engagement and takeover notification interval on vehicle control performance during the takeover, by comparing between the high and low engagement groups in younger and older drivers, across two takeover notification interval conditions. We found that both younger and older drivers engaged in various non-driving-related activities during the automated driving portion, with distinct preferences on the type of activity for each age group (i.e., while younger drivers mostly used an electronic device, older drivers tended to converse). There were also significant differences between the two age groups and between the two notification intervals on various driving performance measures. Older drivers benefited more than younger drivers from the longer interval in terms of response time to notifications. Voluntary engagement in non-driving-related activities did not impair takeover performance in general, although there was a trend of older drivers who were

Do management practices support or constrain safe driving behaviour? A multi-level investigation in a sample of occupational drivers.

Science.gov (United States)

Newnam, Sharon; Warmerdam, Amanda; Sheppard, Dianne; Griffin, Mark; Stevenson, Mark

2017-05-01

It has been estimated that one-third of all work-related deaths occur while driving for work-related purposes. Despite this, many organisations are unaware of the practices, beyond those that identify and control the impact of unforeseen events (i.e., risk management), that predispose drivers to risk. This study addresses the issue by identifying the management practices operationalised as, High Performance Workplace Systems (HPWS) that influence safe driver behaviour. The study also explores the value given to safety by senior level management as a moderator of the relationship between HPWS practices and driver behaviour. Each factor was tested within a two level hierarchical model consisting of 911 drivers, nested within 161 supervisors and 83 organisations. The findings highight that under conditions of high investment in job and work design, communication and selection practices, drivers reported poorer driving behaviour. An interaction effect also demonstrated that under conditions of high investment in remuneration, drivers reported safer behaviour, but only when they perceived that managers valued and prioritised safety. The findings challenge current thinking in the management of workplace road safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dementia & Driving

Science.gov (United States)

... have to give up driving. Many people associate driving with self-reliance and freedom; the loss of driving privileges ... familiar roads and avoid long distances. Avoid heavy traffic and heavily traveled roads. Avoid driving at night and in bad weather. Reduce the ...

Factors affecting self-regulatory driving practices among older adults.

Science.gov (United States)

Molnar, Lisa J; Charlton, Judith L; Eby, David W; Langford, Jim; Koppel, Sjaan; Kolenic, Giselle E; Marshall, Shawn

2014-01-01

The primary objective of this study was to better understand how self-regulatory driving practices at multiple levels of driver decision making are influenced by various factors. Specifically, the study investigated patterns of tactical and strategic self-regulation among a sample of 246 Australian older drivers. Of special interest was the relative influence of several variables on the adoption of self-regulation, including self-perceptions of health, functioning, and abilities for safe driving and driving confidence and comfort. The research was carried out at the Monash University Accident Research Centre, as part of its Ozcandrive study, a partnership with the Canadian Driving Research Initiative for Vehicular Safety in the Elderly (Candrive), and in conjunction with the University of Michigan Transportation Research Institute (UMTRI). Candrive/Ozcandrive represents the first study to follow a large group of older drivers over several years and collect comprehensive self-reported and objectively derived data on health, functioning, and driving. This study used a subset of data from the Candrive/Ozcandrive study. Upon enrolling in the study, participants underwent a comprehensive clinical assessment during which data on visual, cognitive, and psychomotor functioning were collected. Approximately 4 months after study enrollment, participants completed the Advanced Driving Decisions and Patterns of Travel (ADDAPT) questionnaire, a computer-based self-regulation instrument developed and pilot-tested at UMTRI. Self-regulation among older adults was found to be a multidimensional concept. Rates of self-regulation were tied closely to specific driving situations, as well as level of decision making. In addition, self-regulatory practices at the strategic and tactical levels of decision making were influenced by different sets of factors. Continuing efforts to better understand the self-regulatory practices of older drivers at multiple levels of driver performance and

Sleep driving: sleepwalking variant or misuse of z-drugs?

Science.gov (United States)

Pressman, Mark R

2011-10-01

Sleep driving is most often classified as a variant of sleepwalking, but should be distinguished from impaired driving due to misuse or abuse of sedative/hypnotic drugs. Z-drugs; zolpidem and zopiclone in particular, have been associated with the majority of reported cases of impaired driving. Numerous studies have found z-drugs in driving under influence (DUI) related police stops, arrests and accidents. Impaired drivers are reported to have 1) blood levels of z-drugs that exceed therapeutic ranges 2) failed to take the medication at the correct time or remain in bed for sufficient time and/or 3) combined z-drugs with other central nervous system (CNS) depressants and/or alcohol. Consistent with CNS depression, z-drug-impaired drivers may demonstrate cognitive function at low levels with drivers still able to understand and respond to questions while sleepwalkers are completely unable to understand or interact with police. Z-drug-impaired drivers are often severely physically impaired, unable to stand up or maintain balance while sleepwalkers are able to stand and walk unaided. Sleep driving and impaired driving due to z-drugs may overlap. Sleep driving and drug-impaired driving are statistically rare events, but due to the billions of doses prescribed each year may still result in numerous DUI related arrests and accidents. Copyright © 2010 Elsevier Ltd. All rights reserved.

Temporal alcohol availability predicts first-time drunk driving, but not repeat offending.

Science.gov (United States)

Schofield, Timothy P; Denson, Thomas F

2013-01-01

Alcohol availability has been linked to drunk driving, but research has not examined whether this relationship is the same for first-time and repeat offenses. We examined the relationship between the business hours of alcohol outlets licensed to serve alcohol for on-premises consumption and misdemeanor-level (first offense) and felony-level drunk driving (repeat offense) charges in New York State in 2009. Longer outlet business hours were associated with more misdemeanor drunk driving charges, but were not associated with felony drunk driving charges. The per capita density of on-premises alcohol outlets did not affect misdemeanor or felony drunk driving charges. The results suggest that temporal alcohol availability may be an impelling factor for first-time drunk driving, but other factors likely influence repeat drunk driving behaviors.

Temporal alcohol availability predicts first-time drunk driving, but not repeat offending.

Directory of Open Access Journals (Sweden)

Timothy P Schofield

Full Text Available Alcohol availability has been linked to drunk driving, but research has not examined whether this relationship is the same for first-time and repeat offenses. We examined the relationship between the business hours of alcohol outlets licensed to serve alcohol for on-premises consumption and misdemeanor-level (first offense and felony-level drunk driving (repeat offense charges in New York State in 2009. Longer outlet business hours were associated with more misdemeanor drunk driving charges, but were not associated with felony drunk driving charges. The per capita density of on-premises alcohol outlets did not affect misdemeanor or felony drunk driving charges. The results suggest that temporal alcohol availability may be an impelling factor for first-time drunk driving, but other factors likely influence repeat drunk driving behaviors.

The effects of texting on driving performance in a driving simulator: the influence of driver age.

Science.gov (United States)

Rumschlag, Gordon; Palumbo, Theresa; Martin, Amber; Head, Doreen; George, Rajiv; Commissaris, Randall L

2015-01-01

Distracted driving is a significant contributor to motor vehicle accidents and fatalities, and texting is a particularly significant form of driver distraction that continues to be on the rise. The present study examined the influence of driver age (18-59 years old) and other factors on the disruptive effects of texting on simulated driving behavior. While 'driving' the simulator, subjects were engaged in a series of brief text conversations with a member of the research team. The primary dependent variable was the occurrence of Lane Excursions (defined as any time the center of the vehicle moved outside the directed driving lane, e.g., into the lane for oncoming traffic or onto the shoulder of the road), measured as (1) the percent of subjects that exhibited Lane Excursions, (2) the number of Lane Excursions occurring and (3) the percent of the texting time in Lane Excursions. Multiple Regression analyses were used to assess the influence of several factors on driving performance while texting, including text task duration, texting skill level (subject-reported), texting history (#texts/week), driver gender and driver age. Lane Excursions were not observed in the absence of texting, but 66% of subjects overall exhibited Lane Excursions while texting. Multiple Regression analysis for all subjects (N=50) revealed that text task duration was significantly correlated with the number of Lane Excursions, and texting skill level and driver age were significantly correlated with the percent of subjects exhibiting Lane Excursions. Driver gender was not significantly correlated with Lane Excursions during texting. Multiple Regression analysis of only highly skilled texters (N=27) revealed that driver age was significantly correlated with the number of Lane Excursions, the percent of subjects exhibiting Lane Excursions and the percent of texting time in Lane Excursions. In contrast, Multiple Regression analysis of those drivers who self-identified as not highly skilled

A qualitative exploration of driving stress and driving discourtesy.

Science.gov (United States)

Scott-Parker, B; Jones, C M; Rune, K; Tucker, J

2018-05-31

Driving courtesy, and conversely driving discourtesy, recently has been of great interest in the public domain. In addition, there has been increasing recognition of the negative impact of stress upon the individual's health and wellbeing, with a plethora of interventions aimed at minimising stress more generally. The research literature regarding driving dis/courtesy, in comparison, is scant, with a handful of studies examining the dis/courteous driving behaviour of road users, and the relationship between driving discourtesy and driving stress. To examine courteous and discourteous driving experiences, and to explore the impact of stress associated with such driving experiences. Thirty-eight drivers (20 females) from the Sunshine Coast region volunteered to participate in one of four 1-1.5 h focus groups. Content analysis used the verbatim utterances captured via an Mp3 device. Three themes pertaining to stressful and discourteous interactions were identified. Theme one pertained to the driving context: road infrastructure (eg, roundabouts, roadwork), vehicles (eg, features), location (eg, country vs city, unfamiliar areas), and temporal aspects (eg, holidays). Theme two pertained to other road users: their behaviour (eg, tailgating, merging), and unknown factors (eg, illicit and licit drug use). Theme three pertained to the self as road user: their own behaviours (eg, deliberate intimidation), and their emotions (eg, angry reaction to other drivers, being in control). Driving dis/courtesy and driving stress is a complex phenomenon, suggesting complex intervention efforts are required. Driving discourtesy was reported as being highly stressful, therefore intervention efforts which encourage driving courtesy and which foster emotional capacity to cope with stressful circumstances appear warranted. Copyright © 2018. Published by Elsevier Ltd.

Changes in self-reported driving intentions and attitudes while learning to drive in Great Britain.

Science.gov (United States)

Helman, S; Kinnear, N A D; McKenna, F P; Allsop, R E; Horswill, M S

2013-10-01

Novice drivers are overrepresented in traffic collisions, especially in their first year of solo driving. It is widely accepted that some driving behaviours (such as speeding and thrill-seeking) increase risk in this group. Increasingly research is suggesting that attitudes and behavioural intentions held in the pre-driver and learning stage are important in determining later driver behaviour in solo driving. In this study we examine changes in several self-reported attitudes and behavioural intentions across the learning stage in a sample of learner drivers in Great Britain. A sample of 204 learner drivers completed a self-report questionnaire near the beginning of their learning, and then again shortly after they passed their practical driving test. Results showed that self-reported intentions regarding speed choice, perceptions regarding skill level, and intentions regarding thrill-seeking (through driving) became less safe over this time period, while self-reported intentions regarding following distance and overtaking tendency became safer. The results are discussed with reference to models of driver behaviour that focus on task difficulty; it is suggested that the manner in which behind-the-wheel experience relates to the risk measures of interest may be the key determining factor in how these change over the course of learning to drive. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Accuracy of young male drivers’ self-assessments of driving skill

DEFF Research Database (Denmark)

Martinussen, Laila Marianne; Møller, Mette; Prato, Carlo Giacomo

2017-01-01

Accurate self-assessment of skill is important because it creates an appropriate level of confidence and hence behaviour. Inaccurate self-assessment of driving ability has been linked to reckless driving and accidents. Inaccurate self-assessment of driving skills may be a contributing factor...... to the over-representation of young male drivers in accident statistics. Most previous research on self-assessment of driving skills did not compare self-reported skills to objectively measured driving skills, so the aims of this study were: (1) to test the accuracy of young male drivers’ self......-assessments of specific driving skills by comparing them with performance in a driving simulator; (2) to test whether self-assessment accuracy varied with driving skill, driving experience and sensation-seeking propensity. We found that young male drivers’ self-assessments were inconsistent with their driving performance...

Resumption of car driving after total hip replacement.

Science.gov (United States)

Abbas, Ghulam; Waheed, Abdul

2011-04-01

To assess periods required for resuming car driving in 130 patients who had undergone total hip replacement (THR). 80 men and 50 women aged 39 to 80 years who had been driving automatic (n=49) or manual (n=81) cars in the previous 3 months and underwent unilateral primary THR of the right (n=85) or left (n=45) hip were recruited. Patients were advised to resume driving after 6 weeks if they felt comfortable to do so. 105 (81%) patients were able to resume driving at week 6 to 8; 67 (64%) had had a right THR and 65 (62%) were manual car drivers. 22 (17%) patients were able to do so at week 12. The remaining 3 (2%) patients were not confident to drive even at week 12. No patient reported deterioration in driving ability, whereas 48 (38%) felt a subjective improvement in their driving ability. The time to resume driving varies in different patients. The advice should be individualised, depending on the patient's recovery and confidence level.

The importance of damper drive performance for clean air

International Nuclear Information System (INIS)

Wistrom, K.

2002-01-01

Amendments to the U.S. Federal Clean Air Act require petroleum refineries and other industries to examine every aspects of their process heating operations in order to reduce cumulative nitrogen oxide emissions from their plants. It has been found that changing the final damper control elements to more reliable and accurate damper drives greatly improves the combustion of air and flue gases and reduces tramp air from entering furnaces. This paper discusses the increasing importance of precise damper drives in nitrogen oxides reduction efforts, and the challenges involved in effecting good damper control. It also provides some technical details about final control drives, manufactured by TYPE K Damper Drives, a division of Controls International Inc., that thrive in environments of extreme temperatures, heavy vibration and fly ash, while providing continuous duty service with smooth, accurate and repeatable damper positioning. Case history of an Ontario oil refinery installing several damper drives designed by TYPE K, indicating high level of nitrogen oxides reduction is described to illustrate the importance and the advantages of damper control drives designed by this firm. In addition to meeting regulatory requirements, additional benefits include improved product quality and safety levels, combined with lower maintenance expenses. photos

Electric drives

CERN Document Server

Boldea, Ion

2005-01-01

ENERGY CONVERSION IN ELECTRIC DRIVESElectric Drives: A DefinitionApplication Range of Electric DrivesEnergy Savings Pay Off RapidlyGlobal Energy Savings Through PEC DrivesMotor/Mechanical Load MatchMotion/Time Profile MatchLoad Dynamics and StabilityMultiquadrant OperationPerformance IndexesProblemsELECTRIC MOTORS FOR DRIVESElectric Drives: A Typical ConfigurationElectric Motors for DrivesDC Brush MotorsConventional AC MotorsPower Electronic Converter Dependent MotorsEnergy Conversion in Electric Motors/GeneratorsPOWER ELECTRONIC CONVERTERS (PECs) FOR DRIVESPower Electronic Switches (PESs)The

Effect of driving pressure on mortality in ARDS patients during lung protective mechanical ventilation in two randomized controlled trials.

Science.gov (United States)

Guérin, Claude; Papazian, Laurent; Reignier, Jean; Ayzac, Louis; Loundou, Anderson; Forel, Jean-Marie

2016-11-29

Driving pressure (ΔPrs) across the respiratory system is suggested as the strongest predictor of hospital mortality in patients with acute respiratory distress syndrome (ARDS). We wonder whether this result is related to the range of tidal volume (V T ). Therefore, we investigated ΔPrs in two trials in which strict lung-protective mechanical ventilation was applied in ARDS. Our working hypothesis was that ΔPrs is a risk factor for mortality just like compliance (Crs) or plateau pressure (Pplat,rs) of the respiratory system. We performed secondary analysis of data from 787 ARDS patients enrolled in two independent randomized controlled trials evaluating distinct adjunctive techniques while they were ventilated as in the low V T arm of the ARDSnet trial. For this study, we used V T , positive end-expiratory pressure (PEEP), Pplat,rs, Crs, ΔPrs, and respiratory rate recorded 24 hours after randomization, and compared them between survivors and nonsurvivors at day 90. Patients were followed for 90 days after inclusion. Cox proportional hazard modeling was used for mortality at day 90. If colinearity between ΔPrs, Crs, and Pplat,rs was verified, specific Cox models were used for each of them. Both trials enrolled 805 patients of whom 787 had day-1 data available, and 533 of these survived. In the univariate analysis, ΔPrs averaged 13.7 ± 3.7 and 12.8 ± 3.7 cmH 2 O (P = 0.002) in nonsurvivors and survivors, respectively. Colinearity between ΔPrs, Crs and Pplat,rs, which was expected as these variables are mathematically coupled, was statistically significant. Hazard ratios from the Cox models for day-90 mortality were 1.05 (1.02-1.08) (P = 0.005), 1.05 (1.01-1.08) (P = 0.008) and 0.985 (0.972-0.985) (P = 0.029) for ΔPrs, Pplat,rs and Crs, respectively. PEEP and V T were not associated with death in any model. When ventilating patients with low V T , ΔPrs is a risk factor for death in ARDS patients, as is Pplat,rs or Crs. As our data

Control rod driving hydraulic pressure device

International Nuclear Information System (INIS)

Ishida, Kazuo.

1990-01-01

Discharged water after actuating control rod drives in a BWR type reactor is once discharged to a discharging header, then returned to a master control unit and, subsequently, discharged to a reactor by way of a cooling water header. The radioactive level in the discharging header and the master control unit is increased by the reactor water to increase the operator's exposure. In view of the above, a riser is disposed for connecting a hydraulic pressure control unit incorporating a directional control valve and the cooling water head. When a certain control rod is inserted, the pressurized driving water is supplied through a hydraulic pressure control unit to the control rod drives. The discharged water from the control rod drives is entered by way of the hydraulic pressure control unit into the cooling water header and then returned to the reactor by way of other hydraulic pressure control unit and the control rod drives. Thus, the reactor water is no more recycled to the master control unit to reduce the radioactive exposure. (N.H.)

Jerky driving--An indicator of accident proneness?

Science.gov (United States)

Bagdadi, Omar; Várhelyi, András

2011-07-01

This study uses continuously logged driving data from 166 private cars to derive the level of jerks caused by the drivers during everyday driving. The number of critical jerks found in the data is analysed and compared with the self-reported accident involvement of the drivers. The results show that the expected number of accidents for a driver increases with the number of critical jerks caused by the driver. Jerk analyses make it possible to identify safety critical driving behaviour or "accident prone" drivers. They also facilitate the development of safety measures such as active safety systems or advanced driver assistance systems, ADAS, which could be adapted for specific groups of drivers or specific risky driving behaviour. Copyright © 2011 Elsevier Ltd. All rights reserved.

Older drivers with cognitive impairment: Perceived changes in driving skills, driving-related discomfort and self-regulation of driving

DEFF Research Database (Denmark)

Meng, A.; Siren, A.; Teasdale, Thomas William

2013-01-01

The results of a previous study indicate that in general, older drivers who recognise cognitive problems show realistic self-assessment of changes in their driving skills and that driving-related discomfort may function as an indirect monitoring of driving ability, contributing to their safe...... drivers may recognise cognitive problems, they tend not to recognise changes to their driving, which may reflect reluctance to acknowledge the impact of cognitive impairment on their driving. Furthermore, the results suggest that driving-related discomfort plays an important role in the self......-regulation of driving among cognitively impaired older drivers. However, it is less clear what triggers driving-related discomfort among cognitively impaired older drivers indicating that it may be a less reliable aspect of their self-monitoring of driving ability....

Neutral-point current modeling and control for Neutral-Point Clamped three-level converter drive with small DC-link capacitors

DEFF Research Database (Denmark)

Maheshwari, Ram Krishan; Munk-Nielsen, Stig; Busquets-Monge, Sergio

2011-01-01

A Neutral-Point-Clamped (NPC) three-level inverter with small DC-link capacitors is presented in this paper. This inverter requires zero average neutral-point current for stable neutral-point potential. A simple carrier based modulation strategy is proposed for achieving zero average neutral...... drive with only 14 μF DC-link capacitors. A fast and stable performance of the neutral-point voltage controller is achieved and verified by experiments....

Assessing the Driver’s Current Level of Working Memory Load with High Density Functional Near-infrared Spectroscopy: A Realistic Driving Simulator Study

Science.gov (United States)

Unni, Anirudh; Ihme, Klas; Jipp, Meike; Rieger, Jochem W.

2017-01-01

Cognitive overload or underload results in a decrease in human performance which may result in fatal incidents while driving. We envision that driver assistive systems which adapt their functionality to the driver’s cognitive state could be a promising approach to reduce road accidents due to human errors. This research attempts to predict variations of cognitive working memory load levels in a natural driving scenario with multiple parallel tasks and to reveal predictive brain areas. We used a modified version of the n-back task to induce five different working memory load levels (from 0-back up to 4-back) forcing the participants to continuously update, memorize, and recall the previous ‘n’ speed sequences and adjust their speed accordingly while they drove for approximately 60 min on a highway with concurrent traffic in a virtual reality driving simulator. We measured brain activation using multichannel whole head, high density functional near-infrared spectroscopy (fNIRS) and predicted working memory load level from the fNIRS data by combining multivariate lasso regression and cross-validation. This allowed us to predict variations in working memory load in a continuous time-resolved manner with mean Pearson correlations between induced and predicted working memory load over 15 participants of 0.61 [standard error (SE) 0.04] and a maximum of 0.8. Restricting the analysis to prefrontal sensors placed over the forehead reduced the mean correlation to 0.38 (SE 0.04), indicating additional information gained through whole head coverage. Moreover, working memory load predictions derived from peripheral heart rate parameters achieved much lower correlations (mean 0.21, SE 0.1). Importantly, whole head fNIRS sampling revealed increasing brain activation in bilateral inferior frontal and bilateral temporo-occipital brain areas with increasing working memory load levels suggesting that these areas are specifically involved in workload-related processing. PMID

Assessing the Driver’s Current Level of Working Memory Load with High Density Functional Near-infrared Spectroscopy: A Realistic Driving Simulator Study

Directory of Open Access Journals (Sweden)

Anirudh Unni

2017-04-01

Full Text Available Cognitive overload or underload results in a decrease in human performance which may result in fatal incidents while driving. We envision that driver assistive systems which adapt their functionality to the driver’s cognitive state could be a promising approach to reduce road accidents due to human errors. This research attempts to predict variations of cognitive working memory load levels in a natural driving scenario with multiple parallel tasks and to reveal predictive brain areas. We used a modified version of the n-back task to induce five different working memory load levels (from 0-back up to 4-back forcing the participants to continuously update, memorize, and recall the previous ‘n’ speed sequences and adjust their speed accordingly while they drove for approximately 60 min on a highway with concurrent traffic in a virtual reality driving simulator. We measured brain activation using multichannel whole head, high density functional near-infrared spectroscopy (fNIRS and predicted working memory load level from the fNIRS data by combining multivariate lasso regression and cross-validation. This allowed us to predict variations in working memory load in a continuous time-resolved manner with mean Pearson correlations between induced and predicted working memory load over 15 participants of 0.61 [standard error (SE 0.04] and a maximum of 0.8. Restricting the analysis to prefrontal sensors placed over the forehead reduced the mean correlation to 0.38 (SE 0.04, indicating additional information gained through whole head coverage. Moreover, working memory load predictions derived from peripheral heart rate parameters achieved much lower correlations (mean 0.21, SE 0.1. Importantly, whole head fNIRS sampling revealed increasing brain activation in bilateral inferior frontal and bilateral temporo-occipital brain areas with increasing working memory load levels suggesting that these areas are specifically involved in workload

Drive Stands

Data.gov (United States)

Federal Laboratory Consortium — The Electrical Systems Laboratory (ESL)houses numerous electrically driven drive stands. A drive stand consists of an electric motor driving a gearbox and a mounting...

Comparing Expert and Novice Driving Behavior in a Driving Simulator

Directory of Open Access Journals (Sweden)

Hiran B. Ekanayake

2014-02-01

Full Text Available This paper presents a study focused on comparing driving behavior of expert and novice drivers in a mid-range driving simulator with the intention of evaluating the validity of driving simulators for driver training. For the investigation, measurements of performance, psychophysiological measurements, and self-reported user experience under different conditions of driving tracks and driving sessions were analyzed. We calculated correlations between quantitative and qualitative measures to enhance the reliability of the findings. The experiment was conducted involving 14 experienced drivers and 17 novice drivers. The results indicate that driving behaviors of expert and novice drivers differ from each other in several ways but it heavily depends on the characteristics of the task. Moreover, our belief is that the analytical framework proposed in this paper can be used as a tool for selecting appropriate driving tasks as well as for evaluating driving performance in driving simulators.

Assessing drivers' response during automated driver support system failures with non-driving tasks.

Science.gov (United States)

Shen, Sijun; Neyens, David M

2017-06-01

With the increase in automated driver support systems, drivers are shifting from operating their vehicles to supervising their automation. As a result, it is important to understand how drivers interact with these automated systems and evaluate their effect on driver responses to safety critical events. This study aimed to identify how drivers responded when experiencing a safety critical event in automated vehicles while also engaged in non-driving tasks. In total 48 participants were included in this driving simulator study with two levels of automated driving: (a) driving with no automation and (b) driving with adaptive cruise control (ACC) and lane keeping (LK) systems engaged; and also two levels of a non-driving task (a) watching a movie or (b) no non-driving task. In addition to driving performance measures, non-driving task performance and the mean glance duration for the non-driving task were compared between the two levels of automated driving. Drivers using the automated systems responded worse than those manually driving in terms of reaction time, lane departure duration, and maximum steering wheel angle to an induced lane departure event. These results also found that non-driving tasks further impaired driver responses to a safety critical event in the automated system condition. In the automated driving condition, driver responses to the safety critical events were slower, especially when engaged in a non-driving task. Traditional driver performance variables may not necessarily effectively and accurately evaluate driver responses to events when supervising autonomous vehicle systems. Thus, it is important to develop and use appropriate variables to quantify drivers' performance under these conditions. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.

Driving impairments in teens and adults with attention-deficit/hyperactivity disorder.

Science.gov (United States)

Barkley, Russell A

2004-06-01

Available research provides compelling evidence that ADHD is associated with significantly increased risks for various adverse outcomes while driving, including increased traffic citations (particularly speeding), motor vehicle crashes for which the driver is at fault, repeated crash occurrences,and more severe crashes as determined from dollar damage and likelihood of bodily injuries from the crash. Not surprisingly, teens and adults with ADHD are more likely to have their licenses suspended and even fully revoked. Research further suggests that these driving risks cannot be accounted for by the comorbid disorders likely to be associated with ADHD, such as ODD, conduct disorder (CD), depression, or anxiety, or by lower than normal levels of intelligence. Recent attempts to study the processes or mechanisms involved in driving in adults with ADHD offer some explanation of how the disorder conveys such increased risks. Driving can be conceptualized usefully as involving at least three or more dimensions or levels, including basic cognitive abilities necessary for driving (operational), actual skills for maneuvering the vehicle in traffic (tactical), and the more executive, goal-directed aspects of driving(strategic). The findings of studies indicate that ADHD interferes with the basic operational components of driving by means of the impairments it produces in attention, resistance to distraction, response inhibition, slower and more variable reaction time, and the capacity to follow rules that may compete with ongoing sensory information. Accumulating evidence also points to a problem in the tactical level of driving, such that those with ADHDrate themselves and are rated by others as employing less safe driving habits during their normal operation of a vehicle than are adults in community control groups. Although this has been more elusive to demonstrate through the use of simple laboratory-based driving simulators. more modern virtual reality driving platforms

Perceptual load in different regions of the visual scene and its relevance for driving.

Science.gov (United States)

Marciano, Hadas; Yeshurun, Yaffa

2015-06-01

The aim of this study was to better understand the role played by perceptual load, at both central and peripheral regions of the visual scene, in driving safety. Attention is a crucial factor in driving safety, and previous laboratory studies suggest that perceptual load is an important factor determining the efficiency of attentional selectivity. Yet, the effects of perceptual load on driving were never studied systematically. Using a driving simulator, we orthogonally manipulated the load levels at the road (central load) and its sides (peripheral load), while occasionally introducing critical events at one of these regions. Perceptual load affected driving performance at both regions of the visual scene. Critically, the effect was different for central versus peripheral load: Whereas load levels on the road mainly affected driving speed, load levels on its sides mainly affected the ability to detect critical events initiating from the roadsides. Moreover, higher levels of peripheral load impaired performance but mainly with low levels of central load, replicating findings with simple letter stimuli. Perceptual load has a considerable effect on driving, but the nature of this effect depends on the region of the visual scene at which the load is introduced. Given the observed importance of perceptual load, authors of future studies of driving safety should take it into account. Specifically, these findings suggest that our understanding of factors that may be relevant for driving safety would benefit from studying these factors under different levels of load at different regions of the visual scene. © 2014, Human Factors and Ergonomics Society.

Acceptance of and Engagement in Risky Driving Behaviors by Teenagers

Science.gov (United States)

Sarkar, Sheila; Andreas, Marie

2004-01-01

Data gathered from 1,430 teenage student drivers and 880 teenage traffic violators were used to examine the levels of exposure to risky driving behaviors and perceptions concerning the level of danger of such behaviors. For student drivers, 55% reported exposure to risky driving by being in a car with a driver engaging in such activities as drunk…

Cognitive problems, self-rated changes in driving skills, driving-related discomfort and self-regulation of driving in old drivers

DEFF Research Database (Denmark)

Meng, Annette; Siren, Anu Kristiina

2012-01-01

Ageing in general is associated with functional decline that may have an adverse effect on driving. Nevertheless, older drivers have been found to show good judgement and to self-regulate their driving, which may enable them to continue driving safely despite functional decline. The process...... of the self-monitoring of driving ability and the awareness of functional decline, and its association with the self-regulation of driving is, however, not fully understood. The aim of the present study was to examine the perceived changes in driving skills, the discomfort experienced in driving, and the self......-related discomfort is an important factor affecting the self-regulation of driving. Finally, the findings indicate that driving-related discomfort functions as an indirect self-monitoring of driving ability and may contribute to the safe driving performance of Danish older drivers....

Driver's behavioural changes with new intelligent transport system interventions at railway level crossings--A driving simulator study.

Science.gov (United States)

Larue, Grégoire S; Kim, Inhi; Rakotonirainy, Andry; Haworth, Narelle L; Ferreira, Luis

2015-08-01

Improving safety at railway level crossings is an important issue for the Australian transport system. Governments, the rail industry and road organisations have tried a variety of countermeasures for many years to improve railway level crossing safety. New types of intelligent transport system (ITS) interventions are now emerging due to the availability and the affordability of technology. These interventions target both actively and passively protected railway level crossings and attempt to address drivers' errors at railway crossings, which are mainly a failure to detect the crossing or the train and misjudgement of the train approach speed and distance. This study aims to assess the effectiveness of three emerging ITS that the rail industry considers implementing in Australia: a visual in-vehicle ITS, an audio in-vehicle ITS, as well as an on-road flashing beacons intervention. The evaluation was conducted on an advanced driving simulator with 20 participants per trialled technology, each participant driving once without any technology and once with one of the ITS interventions. Every participant drove through a range of active and passive crossings with and without trains approaching. Their speed approach of the crossing, head movements and stopping compliance were measured. Results showed that driver behaviour was changed with the three ITS interventions at passive crossings, while limited effects were found at active crossings, even with reduced visibility. The on-road intervention trialled was unsuccessful in improving driver behaviour; the audio and visual ITS improved driver behaviour when a train was approaching. A trend toward worsening driver behaviour with the visual ITS was observed when no trains were approaching. This trend was not observed for the audio ITS intervention, which appears to be the ITS intervention with the highest potential for improving safety at passive crossings. Copyright © 2015 Elsevier Ltd. All rights reserved.

Creating a driving profile for older adults using GPS devices and naturalistic driving methodology.

Science.gov (United States)

Babulal, Ganesh M; Traub, Cindy M; Webb, Mollie; Stout, Sarah H; Addison, Aaron; Carr, David B; Ott, Brian R; Morris, John C; Roe, Catherine M

2016-01-01

Background/Objectives : Road tests and driving simulators are most commonly used in research studies and clinical evaluations of older drivers. Our objective was to describe the process and associated challenges in adapting an existing, commercial, off-the-shelf (COTS), in-vehicle device for naturalistic, longitudinal research to better understand daily driving behavior in older drivers. Design : The Azuga G2 Tracking Device TM was installed in each participant's vehicle, and we collected data over 5 months (speed, latitude/longitude) every 30-seconds when the vehicle was driven.  Setting : The Knight Alzheimer's Disease Research Center at Washington University School of Medicine. Participants : Five individuals enrolled in a larger, longitudinal study assessing preclinical Alzheimer disease and driving performance.  Participants were aged 65+ years and had normal cognition. Measurements :  Spatial components included Primary Location(s), Driving Areas, Mean Centers and Unique Destinations.  Temporal components included number of trips taken during different times of the day.  Behavioral components included number of hard braking, speeding and sudden acceleration events. Methods :  Individual 30-second observations, each comprising one breadcrumb, and trip-level data were collected and analyzed in R and ArcGIS.  Results : Primary locations were confirmed to be 100% accurate when compared to known addresses.  Based on the locations of the breadcrumbs, we were able to successfully identify frequently visited locations and general travel patterns.  Based on the reported time from the breadcrumbs, we could assess number of trips driven in daylight vs. night.  Data on additional events while driving allowed us to compute the number of adverse driving alerts over the course of the 5-month period. Conclusions : Compared to cameras and highly instrumented vehicle in other naturalistic studies, the compact COTS device was quickly installed and transmitted high

Motorcycle emissions and fuel consumption in urban and rural driving conditions.

Science.gov (United States)

Chen, K S; Wang, W C; Chen, H M; Lin, C F; Hsu, H C; Kao, J H; Hu, M T

2003-08-01

This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO(x)=NO+NO(2)) and carbon dioxide (CO(2)), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO(x) emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations.

Motorcycle emissions and fuel consumption in urban and rural driving conditions

International Nuclear Information System (INIS)

Chen, K.S.; Wang, W.C.; Chen, H.M.; Lin, C.F.; Hsu, H.C.; Kao, J.H.; Hu, M.T.

2003-01-01

This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO x =NO+NO 2 ) and carbon dioxide (CO 2 ), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO x emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations

Cognitive Load Measurement in a Virtual Reality-based Driving System for Autism Intervention.

Science.gov (United States)

Zhang, Lian; Wade, Joshua; Bian, Dayi; Fan, Jing; Swanson, Amy; Weitlauf, Amy; Warren, Zachary; Sarkar, Nilanjan

2017-01-01

Autism Spectrum Disorder (ASD) is a highly prevalent neurodevelopmental disorder with enormous individual and social cost. In this paper, a novel virtual reality (VR)-based driving system was introduced to teach driving skills to adolescents with ASD. This driving system is capable of gathering eye gaze, electroencephalography, and peripheral physiology data in addition to driving performance data. The objective of this paper is to fuse multimodal information to measure cognitive load during driving such that driving tasks can be individualized for optimal skill learning. Individualization of ASD intervention is an important criterion due to the spectrum nature of the disorder. Twenty adolescents with ASD participated in our study and the data collected were used for systematic feature extraction and classification of cognitive loads based on five well-known machine learning methods. Subsequently, three information fusion schemes-feature level fusion, decision level fusion and hybrid level fusion-were explored. Results indicate that multimodal information fusion can be used to measure cognitive load with high accuracy. Such a mechanism is essential since it will allow individualization of driving skill training based on cognitive load, which will facilitate acceptance of this driving system for clinical use and eventual commercialization.

Cognitive Load Measurement in a Virtual Reality-based Driving System for Autism Intervention

Science.gov (United States)

Zhang, Lian; Wade, Joshua; Bian, Dayi; Fan, Jing; Swanson, Amy; Weitlauf, Amy; Warren, Zachary; Sarkar, Nilanjan

2016-01-01

Autism Spectrum Disorder (ASD) is a highly prevalent neurodevelopmental disorder with enormous individual and social cost. In this paper, a novel virtual reality (VR)-based driving system was introduced to teach driving skills to adolescents with ASD. This driving system is capable of gathering eye gaze, electroencephalography, and peripheral physiology data in addition to driving performance data. The objective of this paper is to fuse multimodal information to measure cognitive load during driving such that driving tasks can be individualized for optimal skill learning. Individualization of ASD intervention is an important criterion due to the spectrum nature of the disorder. Twenty adolescents with ASD participated in our study and the data collected were used for systematic feature extraction and classification of cognitive loads based on five well-known machine learning methods. Subsequently, three information fusion schemes—feature level fusion, decision level fusion and hybrid level fusion—were explored. Results indicate that multimodal information fusion can be used to measure cognitive load with high accuracy. Such a mechanism is essential since it will allow individualization of driving skill training based on cognitive load, which will facilitate acceptance of this driving system for clinical use and eventual commercialization. PMID:28966730

Current challenges in autonomous driving

Science.gov (United States)

Barabás, I.; Todoruţ, A.; Cordoş, N.; Molea, A.

2017-10-01

Nowadays the automotive industry makes a quantum shift to a future, where the driver will have smaller and smaller role in driving his or her vehicle ending up being totally excluded. In this paper, we have investigated the different levels of driving automatization, the prospective effects of these new technologies on the environment and traffic safety, the importance of regulations and their current state, the moral aspects of introducing these technologies and the possible scenarios of deploying the autonomous vehicles. We have found that the self-driving technologies are facing many challenges: a) They must make decisions faster in very diverse conditions which can include many moral dilemmas as well; b) They have an important potential in reducing the environmental pollution by optimizing their routes, driving styles by communicating with other vehicles, infrastructures and their environment; c) There is a considerable gap between the self-drive technology level and the current regulations; fortunately, this gap shows a continuously decreasing trend; d) In case of many types of imminent accidents management there are many concerns about the ability of making the right decision. Considering that this field has an extraordinary speed of development, our study is up to date at the submission deadline. Self-driving technologies become increasingly sophisticated and technically accessible, and in some cases, they can be deployed for commercial vehicles as well. According to the current stage of research and development, it is still unclear how the self-driving technologies will be able to handle extreme and unexpected events including their moral aspects. Since most of the traffic accidents are caused by human error or omission, it is expected that the emergence of the autonomous technologies will reduce these accidents in their number and gravity, but the very few currently available test results have not been able to scientifically underpin this issue yet. The

Effects of alcohol on automated and controlled driving performances.

Science.gov (United States)

Berthelon, Catherine; Gineyt, Guy

2014-05-01

Alcohol is the most frequently detected substance in fatal automobile crashes, but its precise mode of action is not always clear. The present study was designed to establish the influence of blood alcohol concentration as a function of the complexity of the scenarios. Road scenarios implying automatic or controlled driving performances were manipulated in order to identify which behavioral parameters were deteriorated. A single blind counterbalanced experiment was conducted on a driving simulator. Sixteen experienced drivers (25.3 ± 2.9 years old, 8 men and 8 women) were tested with 0, 0.3, 0.5, and 0.8 g/l of alcohol. Driving scenarios varied: road tracking, car following, and an urban scenario including events inspired by real accidents. Statistical analyses were performed on driving parameters as a function of alcohol level. Automated driving parameters such as standard deviation of lateral position measured with the road tracking and car following scenarios were impaired by alcohol, notably with the highest dose. More controlled parameters such as response time to braking and number of crashes when confronted with specific events (urban scenario) were less affected by the alcohol level. Performance decrement was greater with driving scenarios involving automated processes than with scenarios involving controlled processes.

DrivingSense: Dangerous Driving Behavior Identification Based on Smartphone Autocalibration

Directory of Open Access Journals (Sweden)

Chunmei Ma

2017-01-01

Full Text Available Since pervasive smartphones own advanced computing capability and are equipped with various sensors, they have been used for dangerous driving behaviors detection, such as drunk driving. However, sensory data gathered by smartphones are noisy, which results in inaccurate driving behaviors estimations. Some existing works try to filter noise from sensor readings, but usually only the outlier data are filtered. The noises caused by hardware of the smartphone cannot be removed from the sensor reading. In this paper, we propose DrivingSense, a reliable dangerous driving behavior identification scheme based on smartphone autocalibration. We first theoretically analyze the impact of the sensor error on the vehicle driving behavior estimation. Then, we propose a smartphone autocalibration algorithm based on sensor noise distribution determination when a vehicle is being driven. DrivingSense leverages the corrected sensor parameters to identify three kinds of dangerous behaviors: speeding, irregular driving direction change, and abnormal speed control. We evaluate the effectiveness of our scheme under realistic environments. The results show that DrivingSense, on average, is able to detect the driving direction change event and abnormal speed control event with 93.95% precision and 90.54% recall, respectively. In addition, the speed estimation error is less than 2.1 m/s, which is an acceptable range.

Temporal Alcohol Availability Predicts First-Time Drunk Driving, but Not Repeat Offending

OpenAIRE

Schofield, Timothy P.; Denson, Thomas F.

2013-01-01

Alcohol availability has been linked to drunk driving, but research has not examined whether this relationship is the same for first-time and repeat offenses. We examined the relationship between the business hours of alcohol outlets licensed to serve alcohol for on-premises consumption and misdemeanor-level (first offense) and felony-level drunk driving (repeat offense) charges in New York State in 2009. Longer outlet business hours were associated with more misdemeanor drunk driving charges...

Psychometrics of the Fitness-to-Drive Screening Measure.

Science.gov (United States)

Classen, Sherrilene; Velozo, Craig A; Winter, Sandra M; Bédard, Michel; Wang, Yanning

2015-01-01

We employed item response theory (IRT), specifically using Rasch modeling, to determine the measurement precision of the Fitness-to-Drive Screening Measure (FTDS), a tool that can be used by caregivers and occupational therapists to help detect at-risk drivers. We examined unidimensionality through the factor structure (how items contribute to the central construct of fitness to drive), rating scale (use of the categories of the rating scale), item/person-level separation (distinguishing between items with different difficulty levels or persons with different ability levels) and reliability, item hierarchy (easier driving items advancing to more difficult driving items), rater reliability, rater effects (severity vs. leniency of a rater), and criterion validity of the FTDS to an on-road assessment, via three rater groups (n = 200 older drivers; n = 200 caregivers; n = 2 evaluators). The FTDS is unidimensional, the rating scale performed well, has good person (> 3.07) and item (> 5.43) separation, good person (> 0.90) and item reliability (> 0.97), with < 10% misfitting items for two rater groups (caregivers and drivers). The intraclass correlation (ICC) coefficient among the three rater groups was significant (.253, p < .001) and the evaluators were the most severe raters. When comparing the caregivers' FTDS rating with the drivers' on-road assessment, the areas under the curve (index of discriminability; caregivers .726, p < .001) suggested concurrent validity between the FTDS and the on-road assessment. Despite limitations, the FTDS is a reliable and accurate screening measure for caregivers to help identify at-risk older drivers and for occupational therapy practitioners to start conversations about driving.

Driving Style Analysis Using Primitive Driving Patterns With Bayesian Nonparametric Approaches

OpenAIRE

Wang, Wenshuo; Xi, Junqiang; Zhao, Ding

2017-01-01

Analysis and recognition of driving styles are profoundly important to intelligent transportation and vehicle calibration. This paper presents a novel driving style analysis framework using the primitive driving patterns learned from naturalistic driving data. In order to achieve this, first, a Bayesian nonparametric learning method based on a hidden semi-Markov model (HSMM) is introduced to extract primitive driving patterns from time series driving data without prior knowledge of the number...

Control rod drive

International Nuclear Information System (INIS)

Okutani, Tetsuro.

1988-01-01

Purpose: To provide a simple and economical control rod drive using a control circuit requiring no pulse circuit. Constitution: Control rods in a BWR type reactor are driven by hydraulic pressure and inserted or withdrawn in the direction of applying the hydraulic pressure. The direction of the hydraulic pressure is controlled by a direction control valve. Since the driving for the control rod is extremely important in view of the operation, a self diagnosis function is disposed for rapid inspection of possible abnormality. In the present invention, two driving contacts are disposed each by one between the both ends of a solenoid valve of the direction control valve for driving the control rod and the driving power source, and diagnosis is conducted by alternately operating them. Therefore, since it is only necessary that the control circuit issues a driving instruction only to one of the two driving contacts, the pulse circuit is no more required. Further, since the control rod driving is conducted upon alignment of the two driving instructions, the reliability of the control rod drive can be improved. (Horiuchi, T.)

A laboratory driving simulation for assessment of driving behavior in adults with ADHD: a controlled study

Directory of Open Access Journals (Sweden)

Aleardi Megan

2007-01-01

Full Text Available Abstract Background It is now estimated that attention deficit-hyperactivity disorder (ADHD afflicts at least 4% of adults in the United States and is associated with high levels of morbidity and functional impairment. One key area of dysfunction associated with ADHD is impaired motor vehicle operation. Our goal was to examine the association between ADHD and specific driving outcomes in a sample of adults using a driving simulator. Methods Subjects were 20 adults with full DSM-IV ADHD and 21 controls without ADHD of equal gender distribution. However, the mean age of subjects with ADHD was somewhat older. All analyses were adjusted for age and gender. All subjects participated in a driving simulation that lasted for one hour and consisted of a short training period, a high stimulus segment and a low stimulus segment with two distinct monotonous periods. Results In the second monotonous period within the low stimulus environment, ADHD subjects were significantly more likely than controls to collide with an obstacle suddenly appearing from the periphery, adjusting for age and gender. Conclusion Adults with ADHD were more likely than controls to collide with an obstacle during a driving simulation suggesting that deficits in directed attention may underlie driving impairments in this population.

Dimensions of driving anger and their relationships with aberrant driving.

Science.gov (United States)

Zhang, Tingru; Chan, Alan H S; Zhang, Wei

2015-08-01

The purpose of this study was to investigate the relationship between driving anger and aberrant driving behaviours. An internet-based questionnaire survey was administered to a sample of Chinese drivers, with driving anger measured by a 14-item short Driving Anger Scale (DAS) and the aberrant driving behaviours measured by a 23-item Driver Behaviour Questionnaire (DBQ). The results of Confirmatory Factor Analysis demonstrated that the three-factor model (hostile gesture, arrival-blocking and safety-blocking) of the DAS fitted the driving anger data well. The Exploratory Factor Analysis on DBQ data differentiated four types of aberrant driving, viz. emotional violation, error, deliberate violation and maintaining progress violation. For the anger-aberration relation, it was found that only "arrival-blocking" anger was a significant positive predictor for all four types of aberrant driving behaviours. The "safety-blocking" anger revealed a negative impact on deliberate violations, a finding different from previously established positive anger-aberration relation. These results suggest that drivers with different patterns of driving anger would show different behavioural tendencies and as a result intervention strategies may be differentially effective for drivers of different profiles. Copyright © 2015 Elsevier Ltd. All rights reserved.

Energy Optimal Control of Induction Motor Drives

DEFF Research Database (Denmark)

Abrahamsen, Flemming

This thesis deals with energy optimal control of small and medium-size variable speed induction motor drives for especially Heating, Ventilation and Air-Condition (HVAC) applications. Optimized efficiency is achieved by adapting the magnetization level in the motor to the load, and the basic...... demonstrated that energy optimal control will sometimes improve and sometimes deteriorate the stability. Comparison of small and medium-size induction motor drives with permanent magnet motor drives indicated why, and in which applications, PM motors are especially good. Calculations of economical aspects...... improvement by energy optimal control for any standard induction motor drive between 2.2 kW and 90 kW. A simple method to evaluate the robustness against load disturbances was developed and used to compare the robustness of different motor types and sizes. Calculation of the oscillatory behavior of a motor...

On the Drive Specificity of Freudian Drives for the Generation of SEEKING Activities: The Importance of the Underestimated Imperative Motor Factor

Directory of Open Access Journals (Sweden)

Michael Kirsch

2018-05-01

Full Text Available Doubters of Freud’s theory of drives frequently mentioned that his approach is outdated and therefore cannot be useful for solving current problems in patients with mental disorders. At present, many scientists believe that affects rather than drives are of utmost importance for the emotional life and the theoretical framework of affective neuroscience, developed by Panksepp, strongly underpinned this view. Panksepp evaluated seven so-called command systems and the SEEKING system is therein of central importance. Panksepp used Pankseppian drives as inputs for the SEEKING system but noted the missing explanation of drive-specific generation of SEEKING activities in his description. Drive specificity requires dual action of the drive: the activation of a drive-specific brain area and the release of the neurotransmitter dopamine. Noticeably, as Freud claimed drive specificity too, it was here analyzed whether a Freudian drive can evoke the generation of drive-specific SEEKING activities. Special importance was addressed to the imperative motor factor in Freud’s drive theory because Panksepp’s formulations focused on neural pathways without specifying underlying neurotransmitter/endocrine factors impelling motor activity. As Panksepp claimed sleep as a Pankseppian drive, we firstly had to classified sleep as a Freudian drive by using three evaluated criteria for a Freudian drive. After that it was possible to identify the imperative motor factors of hunger, thirst, sex, and sleep. Most importantly, all of these imperative motor factors can both activate a drive-specific brain area and release dopamine from dopaminergic neurons, i.e., they can achieve the so-called drive specificity. Surprisingly, an impaired Freudian drive can alter via endocrinological pathways the concentration of the imperative motor factor of a second Freudian drive, obviously in some independence to the level of the metabolic deficit, thereby offering the possibility to

Computerized Design and Generation of Gear Drives With a Localized Bearing Contact and a Low Level of Transmission Errors

Science.gov (United States)

Litvin, F.; Chen, J.; Seol, I.; Kim, D.; Lu, J.; Zhao, X.; Handschuh, R.

1996-01-01

A general approach developed for the computerized simulation of loaded gear drives is presented. In this paper the methodology used to localize the bearing contact, provide a parabolic function of transmission errors, and simulate meshing and contact of unloaded gear drives is developed. The approach developed is applied to spur and helical gears, spiral bevel gears, face-gear drives, and worm-gear drives with cylindrical worms.

A universal gyroscope driving circuit with 70dB amplitude control range

KAUST Repository

Abdelghany, Mohamed A.

2010-08-01

A CMOS variable gain driving circuit with output signal amplitude control for gyroscopes with wide range of quality factors is presented. The driving circuit can be used for gyroscopes with Q values higher than 500. The circuit uses a current-commutating switching mixer to control the gyroscope driving signal level. Conventional driving circuits use automatic gain control (AGC) which suffers from limited linear range and the need for an off-chip capacitor for the peak detector and loop filter. Two stage variable gain amplifier is used in the proposed design to ensure enough gain for oscillation for such a wide range of quality factors. Analog and digital amplitude control methods are used to cover wide range of driving signal amplitude with enough accuracy to hit the maximum driving signal level without sacrificing gyroscope linearity. Due to the high DC gain of the amplifier chain, DC offset resulting from mismatches might saturate the amplifier output. DC offset correction is employed using a secondary negative feedback loop. The proposed driving circuit is being fabricated in 0.6μm CMOS technology. © 2010 IEEE.

Effect of chronic nonmalignant pain on highway driving performance.

Science.gov (United States)

Veldhuijzen, D S; van Wijck, A J M; Wille, F; Verster, J C; Kenemans, J L; Kalkman, C J; Olivier, B; Volkerts, E R

2006-05-01

Most pain patients are treated in an outpatient setting and are engaged in daily activities including driving. Since several studies showed that cognitive functioning may be impaired in chronic nonmalignant pain, the question arises whether or not chronic nonmalignant pain affects driving performance. Therefore, the objective of the present study was to determine the effects of chronic nonmalignant pain on actual highway driving performance during normal traffic. Fourteen patients with chronic nonmalignant pain and 14 healthy controls, matched on age, educational level, and driving experience, participated in the study. Participants performed a standardized on-the-road driving test during normal traffic, on a primary highway. The primary parameter of the driving test is the Standard Deviation of Lateral Position (SDLP). In addition, driving-related skills (tracking, divided attention, and memory) were examined in the laboratory. Subjective assessments, such as pain intensity, and subjective driving quality, were rated on visual analogue scales. The results demonstrated that a subset of chronic nonmalignant pain patients had SDLPs that were higher than the matched healthy controls, indicating worse highway driving performance. Overall, there was a statistically significant difference in highway driving performance between the groups. Further, chronic nonmalignant pain patients rated their subjective driving quality to be normal, although their ratings were significantly lower than those of the healthy controls. No significant effects were found on the laboratory tests.

Switched reluctance drive for mass application

Energy Technology Data Exchange (ETDEWEB)

Bitchkov, M.G.; Ilinski, N.F.; Sementchuk, V.A. [Moscow Power Engineering Inst. (Russian Federation)

2000-07-01

Variable speed drives (VSDs) are the most effective means for energy saving in many practical applications particularly in pumps, fans, compressors, conveyors, etc. Up to now the only wide used VSD is a frequency controlled electric drive with AC induction motor. A switched reluctance drive (SRD) having noticeable advantages such as simple construction, low cost, high reliability, high efficiency, etc. still does not compete with traditional AC drives mainly because of the following unsolved problems: complexity of proper control, necessity of a rotor position sensor, poor acoustic characteristics. Results of R and D project realised in Moscow Power Engineering Institute in co-operation with Jaroslavl electric machine-building plant allowed to overcome the above mentioned problems and to obtain reliable low cost sensorless SRD with high efficiency and acceptable acoustic characteristics. The original sensorless SRD version is based on current measuring and exploiting a specially organized observer that provides a stable drive operation within broad speed-torque ranges. Acoustic SRD characteristics were improved by means of proper current pulses shape control. Small increasing the time of current pulse trailing edge allowed to decrease the noise level to 70 dB(A) and brought the SRD to a vary smooth operation even at a low speed. (orig.)

Older driver fitness-to-drive evaluation using naturalistic driving data.

Science.gov (United States)

Guo, Feng; Fang, Youjia; Antin, Jonathan F

2015-09-01

As our driving population continues to age, it is becoming increasingly important to find a small set of easily administered fitness metrics that can meaningfully and reliably identify at-risk seniors requiring more in-depth evaluation of their driving skills and weaknesses. Sixty driver assessment metrics related to fitness-to-drive were examined for 20 seniors who were followed for a year using the naturalistic driving paradigm. Principal component analysis and negative binomial regression modeling approaches were used to develop parsimonious models relating the most highly predictive of the driver assessment metrics to the safety-related outcomes observed in the naturalistic driving data. This study provides important confirmation using naturalistic driving methods of the relationship between contrast sensitivity and crash-related events. The results of this study provide crucial information on the continuing journey to identify metrics and protocols that could be applied to determine seniors' fitness to drive. Published by Elsevier Ltd.

Automated driving safer and more efficient future driving

CERN Document Server

Horn, Martin

2017-01-01

The main topics of this book include advanced control, cognitive data processing, high performance computing, functional safety, and comprehensive validation. These topics are seen as technological bricks to drive forward automated driving. The current state of the art of automated vehicle research, development and innovation is given. The book also addresses industry-driven roadmaps for major new technology advances as well as collaborative European initiatives supporting the evolvement of automated driving. Various examples highlight the state of development of automated driving as well as the way forward. The book will be of interest to academics and researchers within engineering, graduate students, automotive engineers at OEMs and suppliers, ICT and software engineers, managers, and other decision-makers.

How we can measure the non-driving-task engagement in automated driving: Comparing flow experience and workload.

Science.gov (United States)

Ko, Sang Min; Ji, Yong Gu

2018-02-01

In automated driving, a driver can completely concentrate on non-driving-related tasks (NDRTs). This study investigated the flow experience of a driver who concentrated on NDRTs and tasks that induce mental workload under conditional automation. Participants performed NDRTs under different demand levels: a balanced demand-skill level (fit condition) to induce flow, low-demand level to induce boredom, and high-demand level to induce anxiety. In addition, they performed the additional N-Back task, which artificially induces mental workload. The results showed participants had the longest reaction time when they indicated the highest flow score, and had the longest gaze-on time, road-fixation time, hands-on time, and take-over time under the fit condition. Significant differences were not observed in the driver reaction times in the fit condition and the additional N-Back task, indicating that performing NDRTs that induce a high flow experience could influence driver reaction time similar to performing tasks with a high mental workload. Copyright © 2017. Published by Elsevier Ltd.

Backset-stationary and during car driving.

Science.gov (United States)

Jonsson, Bertil; Stenlund, Hans; Björnstig, Ulf

2008-12-01

The aim of the study was to measure and analyze backset, defined as the horizontal distance between the back of the occupant's head and a point located on the ventral/top aspect of the sewn rim of the head restraint, with the car stationary and during driving, in the driver's position in a modern car. A population of 65 subjects, 35 males and 30 females, was studied in a Volvo V70 car, model year 2007. The subjects were studied in the driver's position, in a self-selected posture. Stationary backset was measured with the technique described by Jonsson et al. (2007) and backset during driving with video analysis. Descriptive data were calculated, and variability and correlation analyses were performed. A t-test was used to test differences of means. Significance level was set to 0.05. In comparison to stationary backset, mean backset during driving was 43 mm greater in males and 41 mm greater in females. Driving backset was 44 mm larger in males than in females. Driving backset was moderately correlated (0.37-0.43) to stature, seated height, and seat back angle in males and moderately correlated (0.44-0.52) to hip width, waist circumference, and weight in females. The overall intraclass correlation coefficient for backset during driving was 0.81 (CI: 0.75-0.86). These results may be of use in designing future updates of test protocols/routines for geometric backset, such as RCAR and RCAR-IIWPG.

Pile Driving

Science.gov (United States)

1987-01-01

Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

Driver headway choice : A comparison between driving simulator and real-road driving

NARCIS (Netherlands)

Risto, M.; Martens, M.H.

2014-01-01

Driving simulators have become an established tool in driver behaviour research by offering a controllable, safe and cost-effective alternative to real world driving. A challenge for using driving simulators as a research tool has been to elicit driving behaviour that equals real world driving. With

Driver headway choice: a comparison between driving simulator and real-road driving

NARCIS (Netherlands)

Risto, Malte; Martens, Marieke Hendrikje

2014-01-01

Driving simulators have become an established tool in driver behaviour research by offering a controllable, safe and cost-effective alternative to real world driving. A challenge for using driving simulators as a research tool has been to elicit driving behaviour that equals real world driving. With

Optimization of parameters of special asynchronous electric drives

Science.gov (United States)

Karandey, V. Yu; Popov, B. K.; Popova, O. B.; Afanasyev, V. L.

2018-03-01

The article considers the solution of the problem of parameters optimization of special asynchronous electric drives. The solution of the problem will allow one to project and create special asynchronous electric drives for various industries. The created types of electric drives will have optimum mass-dimensional and power parameters. It will allow one to realize and fulfill the set characteristics of management of technological processes with optimum level of expenses of electric energy, time of completing the process or other set parameters. The received decision allows one not only to solve a certain optimizing problem, but also to construct dependences between the optimized parameters of special asynchronous electric drives, for example, with the change of power, current in a winding of the stator or rotor, induction in a gap or steel of magnetic conductors and other parameters. On the constructed dependences, it is possible to choose necessary optimum values of parameters of special asynchronous electric drives and their components without carrying out repeated calculations.

Control rod drive mechanism

International Nuclear Information System (INIS)

Mizuno, Katsuyuki.

1976-01-01

Object: To restrict the reduction in performance due to stress corrosion cracks by making use of condensate produced in a turbine steam condenser. Structure: Water produced in a turbine steam condenser is forced into a condensed water desalting unit by low pressure condensate pump. The condensate is purified and then forced by a high pressure condensate pump into a feedwater heater for heating before it is returned to the reactor by a feedwater pump. Part of the condensate issuing from the condensate desalting unit is branched from the remaining portion at a point upstream the pump and is withdrawn into a control rod drive water pump after passing through a motordriven bypass valve, an orifice and a condenser water level control valve, is pressurized in the control rod drive water desalting unit and supplied to a control rod drive water pressure system. The control rod is vertically moved by the valve operation of the water pressure system. Since water of high oxygen concentration does not enter during normal operation, it is possible to prevent the stress cracking of the stainless steel apparatus. (Nakamura, S.)

Water pressure control device for control rod drive

International Nuclear Information System (INIS)

Sato, Hideyuki.

1981-01-01

Purpose: To minimize the fluctuations in the reactor water level upon occurrence of abnormality by inputting the level signal of the reactor to an arithmetic unit for controlling the pressure of control rod drive water to thereby enable effective reactor level control. Constitution: Signal from a flow rate transmitter is inputted into an arithmetic unit to perform constant flow rate control upon normal operation. While on the other hand, if abnormality occurs such as feedwater pump trips, the arithmetic unit is switched from the constant flow rate control to the reactor water level control. Reactor water level signal is inputted into the arithmetic unit and the control valve is most suitably controlled, whereby water is fed from CST to the reactor by way of control rod drive water system to secure the reactor water level if feedwater to the reactor is interrupted by loss of coolants on the feedwater system. Since this enables to minimize the fluctuations in the reactor water level upon abnormality, the reactor water level can be controlled most suitably by the reactor water level signal. (Moriyama, K.)

Driving Safety and Fitness to Drive in Sleep Disorders.

Science.gov (United States)

Tippin, Jon; Dyken, Mark Eric

2017-08-01

Driving an automobile while sleepy increases the risk of crash-related injury and death. Neurologists see patients with sleepiness due to obstructive sleep apnea, narcolepsy, and a wide variety of neurologic disorders. When addressing fitness to drive, the physician must weigh patient and societal health risks and regional legal mandates. The Driver Fitness Medical Guidelines published by the National Highway Traffic Safety Administration (NHTSA) and the American Association of Motor Vehicle Administrators (AAMVA) provide assistance to clinicians. Drivers with obstructive sleep apnea may continue to drive if they have no excessive daytime sleepiness and their apnea-hypopnea index is less than 20 per hour. Those with excessive daytime sleepiness or an apnea-hypopnea index of 20 per hour or more may not drive until their condition is effectively treated. Drivers with sleep disorders amenable to pharmaceutical treatment (eg, narcolepsy) may resume driving as long as the therapy has eliminated excessive daytime sleepiness. Following these guidelines, documenting compliance to recommended therapy, and using the Epworth Sleepiness Scale to assess subjective sleepiness can be helpful in determining patients' fitness to drive.

HARMONIC DRIVE SELECTION

Directory of Open Access Journals (Sweden)

Piotr FOLĘGA

2014-03-01

Full Text Available The variety of types and sizes currently in production harmonic drive is a problem in their rational choice. Properly selected harmonic drive must meet certain requirements during operation, and achieve the anticipated service life. The paper discusses the problems associated with the selection of the harmonic drive. It also presents the algorithm correct choice of harmonic drive. The main objective of this study was to develop a computer program that allows the correct choice of harmonic drive by developed algorithm.

Control rod drives

International Nuclear Information System (INIS)

Futatsugi, Masao.

1980-01-01

Purpose: To secure the reactor operation safety by the provision of a fluid pressure detecting section for control rod driving fluid and a control rod interlock at the midway of the flow pass for supplying driving fluid to the control rod drives. Constitution: Between a driving line and a direction control valve are provided a pressure detecting portion, an alarm generating device, and a control rod inhibition interlock. The driving fluid from a driving fluid source is discharged by way of a pump and a manual valve into the reactor in which the control rods and reactor fuels are contained. In addition, when the direction control valve is switched and the control rods are inserted and extracted by the control rod drives, the pressure in the driving line is always detected by the pressure detection section, whereby if abnormal pressure is resulted, the alarm generating device is actuated to warn the abnormality and the control rod inhibition interlock is actuated to lock the direction control valve thereby secure the safety operation of the reactor. (Seki, T.)

Gender differences in alcohol impairment of simulated driving performance and driving-related skills.

Science.gov (United States)

Miller, Melissa A; Weafer, Jessica; Fillmore, Mark T

2009-01-01

Considerable laboratory research indicates that moderate doses of alcohol impair a broad range of skilled activities related to driving performance in young adults. Although laboratory studies show that the intensity of impairment is generally dependent on the blood alcohol concentration, some reviews of this literature suggest that women might be more sensitive to the impairing effects of alcohol than men. The present study tested this hypothesis. Drawing on data from previous experiments in our laboratory, we compared men and women in terms of the degree to which a challenge dose of alcohol (0.65 g/kg) impaired their simulated driving performance and measures of three separate behavioral and cognitive functions important to driving performance: motor coordination, speed of information processing and information-processing capacity. Alcohol significantly impaired all aspects of performance. Moreover, women displayed greater impairment than men on all behavioral tests and also reported higher levels of subjective intoxication compared with men. Both biological and social-cultural factors have been implicated in gender differences in the behavioral responses to alcohol. The current evidence of heightened sensitivity to alcohol in women highlights the need for better understanding the biological and environmental factors underlying this gender difference.

Shed a light in fatigue detection with near-infrared spectroscopy during long-lasting driving

Science.gov (United States)

Gao, Yuan; Pan, Boan; Li, Kai; Li, Ting

2016-03-01

Fatigue driving is one of the leading roles to induce traffic accident and injury, which urgently desires a novel technique to monitor the fatigue level at driving. Functional near infrared spectroscopy (fNIRS) is capable of noninvasive monitoring brain-activities-related hemodynamic responses. Here, we developed a fINRS imager and setup a classic psychological experiment to trigger visual divided attention which varied responding to driving fatigue, and attempted to record the drive-fatigue-level correlated hemodynamic response in the prefrontal cortex. 7 volunteers were recruited to take 7 hours driving and the experimental test was repeated every 1 hour and 8 times in total. The hemodynamic response were extracted and graphed with pseudo image. The analysis on the relationship between the fNIRS-measured hemodynamic response and fatigue level finally displayed that the oxyhemoglobin concentration in one channel of left prefrontal lobe increased with driving duration in significant correlation. And the spatial pattern of hemodynamic response in the prefrontal lobe varied with driving duration as well. The findings indicated the potential of fNIRSmeasured hemodynamic index in some sensitive spot of prefrontal lobe as a driving fatigue indicator and the promising use of fNIRS in traffic safety field.

Estimating Driving Performance Based on EEG Spectrum Analysis

Directory of Open Access Journals (Sweden)

Jung Tzyy-Ping

2005-01-01

Full Text Available The growing number of traffic accidents in recent years has become a serious concern to society. Accidents caused by driver's drowsiness behind the steering wheel have a high fatality rate because of the marked decline in the driver's abilities of perception, recognition, and vehicle control abilities while sleepy. Preventing such accidents caused by drowsiness is highly desirable but requires techniques for continuously detecting, estimating, and predicting the level of alertness of drivers and delivering effective feedbacks to maintain their maximum performance. This paper proposes an EEG-based drowsiness estimation system that combines electroencephalogram (EEG log subband power spectrum, correlation analysis, principal component analysis, and linear regression models to indirectly estimate driver's drowsiness level in a virtual-reality-based driving simulator. Our results demonstrated that it is feasible to accurately estimate quantitatively driving performance, expressed as deviation between the center of the vehicle and the center of the cruising lane, in a realistic driving simulator.

Aligning for Innovation - Alignment Strategy to Drive Innovation

Science.gov (United States)

Johnson, Hurel; Teltschik, David; Bussey, Horace, Jr.; Moy, James

2010-01-01

With the sudden need for innovation that will help the country achieve its long-term space exploration objectives, the question of whether NASA is aligned effectively to drive the innovation that it so desperately needs to take space exploration to the next level should be entertained. Authors such as Robert Kaplan and David North have noted that companies that use a formal system for implementing strategy consistently outperform their peers. They have outlined a six-stage management systems model for implementing strategy, which includes the aligning of the organization towards its objectives. This involves the alignment of the organization from the top down. This presentation will explore the impacts of existing U.S. industrial policy on technological innovation; assess the current NASA organizational alignment and its impacts on driving technological innovation; and finally suggest an alternative approach that may drive the innovation needed to take the world to the next level of space exploration, with NASA truly leading the way.

Underwater noise reduction of marine pile driving using a double pile.

Science.gov (United States)

2015-12-01

Impact pile driving of steel piles in marine environments produces extremely high sound levels in the water. : It has been shown that current pile driving noise attenuation techniques, such as bubble curtains and : cofferdams, provide limited noise r...

Electric motor drive unit, especially adjustment drive for vehicles

Energy Technology Data Exchange (ETDEWEB)

Litterst, P

1980-05-29

An electric motor drive unit, particularly an adjustment drive for vehicles with at least two parallel drive shafts is described, which is compact and saves space, and whose manufacturing costs are low compared with those of well-known drive units of this type. The drive unit contains a suitable number of magnet systems, preferably permanent magnet systems, whose pole axes are spaced and run parallel. The two pole magnet systems have diametrically opposite shell-shaped segments, to which the poles are fixed. In at least one magnet system the two segments are connected by diametrically opposite flat walls parallel to the pole axes to form a single magnetic circuit pole housing. The segments of at least one other magnet system are arranged on this pole housing so that one of these flat walls is a magnetically conducting, connecting component of the magnetic circuit of the other magnet system.

Drivers’ Age, Gender, Driving Experience, and Aggressiveness as Predictors of Aggressive Driving Behaviour

Directory of Open Access Journals (Sweden)

Perepjolkina Viktorija

2011-12-01

Full Text Available Recent years have seen a growing interest in the problem of aggressive driving. In the presentstudy two demographic variables (gender and age, two non-psychological driving-experiencerelated variables (annual mileage and legal driving experience in years and aggressiveness asa personality trait (including behavioural and affective components as psychological variableof individual differences were examined as potential predictors of aggressive driving. The aimof the study was to find out the best predictors of aggressive driving behaviour. The study wasbased on an online survey, and 228 vehicle drivers in Latvia participated in it. The questionnaireincluded eight-item Aggressive Driving Scale (Bone & Mowen, 2006, short Latvian versionof the Buss-Perry Aggression Questionnaire (AQ; Buss & Perry, 1992, and questions gainingdemographic and driving experience information. Gender, age and annual mileage predictedaggressive driving: being male, young and with higher annual driving exposure were associatedwith higher scores on aggressive driving. Dispositional aggressiveness due to anger componentwas a significant predictor of aggressive diving score. Physical aggression and hostility wereunrelated to aggressive driving. Altogether, the predictors explained a total of 28% of thevariance in aggressive driving behaviour. Findings show that dispositional aggressiveness,especially the anger component, as well as male gender, young age and higher annual mileagehas a predictive validity in relation to aggressive driving. There is a need to extend the scope ofpotential dispositional predictors pertinent to driving aggression.

Transitionless driving on adiabatic search algorithm

Energy Technology Data Exchange (ETDEWEB)

Oh, Sangchul, E-mail: soh@qf.org.qa [Qatar Environment and Energy Research Institute, Qatar Foundation, Doha (Qatar); Kais, Sabre, E-mail: kais@purdue.edu [Qatar Environment and Energy Research Institute, Qatar Foundation, Doha (Qatar); Department of Chemistry, Department of Physics and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States)

2014-12-14

We study quantum dynamics of the adiabatic search algorithm with the equivalent two-level system. Its adiabatic and non-adiabatic evolution is studied and visualized as trajectories of Bloch vectors on a Bloch sphere. We find the change in the non-adiabatic transition probability from exponential decay for the short running time to inverse-square decay in asymptotic running time. The scaling of the critical running time is expressed in terms of the Lambert W function. We derive the transitionless driving Hamiltonian for the adiabatic search algorithm, which makes a quantum state follow the adiabatic path. We demonstrate that a uniform transitionless driving Hamiltonian, approximate to the exact time-dependent driving Hamiltonian, can alter the non-adiabatic transition probability from the inverse square decay to the inverse fourth power decay with the running time. This may open up a new but simple way of speeding up adiabatic quantum dynamics.

Control rod drive mechanism

International Nuclear Information System (INIS)

Futatsugi, Masao; Goto, Mikihiko.

1976-01-01

Purpose: To provide a control rod drive mechanism using water as an operating source, which prevents a phenomenon for forming two-layers of water in the neighbourhood of a return nozzle in a reactor to limit formation of excessive thermal stress to improve a safety. Constitution: In the control rod drive mechanism of the present invention, a heating device is installed in the neighbourhood of a pressure container for a reactor. This heating device is provided to heat return water in the reactor to a level equal to the temperature of reactor water thereby preventing a phenomenon for forming two-layers of water in the reactor. This limits formation of thermal stress in the return nozzle in the reactor. Accordingly, it is possible to minimize damages in the return nozzle portion and yet a possibility of failure in reactor water. (Kawakami, Y.)

Educational Biofeedback Driving Simulator as a Drink-Driving Prevention Strategy.

Science.gov (United States)

Howat, Peter; And Others

1991-01-01

Used experimental driving simulator as basis for strategy to encourage a reduction in drunk driving prevalence using adult male subjects (n=36) who participated in a study group and controls (n=36). Results indicated study group subjects significantly decreased their drunk driving compared to the control group. (ABL)

Do aggressive driving and negative emotional driving mediate the link between impulsiveness and risky driving among young Italian drivers?

Science.gov (United States)

Smorti, Martina; Guarnieri, Silvia

2016-01-01

The present study examined the contribution of impulsiveness and aggressive and negative emotional driving to the prediction of traffic violations and accidents taking into account potential mediation effects. Three hundred and four young drivers completed self-report measures assessing impulsiveness, aggressive and negative emotional driving, driving violations, and accidents. Structural equation modeling was used to assess the direct and indirect effects of impulsiveness on violations and accidents among young drivers through aggressive and negative emotional driving. Impulsiveness only indirectly influenced drivers' violations on the road via both the behavioral and emotional states of the driver. On the contrary, impulsiveness was neither directly nor indirectly associated with traffic accidents. Therefore, impulsiveness modulates young drivers' behavioral and emotional states while driving, which in turn influences risky driving.

Self-Parking Cars – “Killer Application” for Autonomous Driving?

OpenAIRE

Lenz, Barbara; Cyganski, Rita

2017-01-01

Current surveys on the acceptance of automated driving reveal that (potential) users are still quite hesitant towards the new technology. One reason for this reluctance can be found in the lack of obvious usefulness of autonomous driving. Promises that are linked to autonomous driving are often not strong enough or not relevant enough for the everyday user of a car:  - Several benefits occur only on the aggregate level of traffic, like for instance smoother traffic flows.  - Some indi...

Gear bearing drive

Science.gov (United States)

Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor); Weinberg, Brian (Inventor)

2011-01-01

A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

The eco-driving effect of electric vehicles compared to conventional gasoline vehicles

Directory of Open Access Journals (Sweden)

Hideki Kato

2016-10-01

Full Text Available Eco-driving is attractive to the public, not only users of internal-combustion-engine vehicles (ICEVs including hybrid electric vehicles (HEVs but also users of electric vehicles (EVs have interest in eco-driving. In this context, a quantitative evaluation of eco-driving effect of EVs was conducted using a chassis dynamometer (C/D with an “eco-driving test mode.” This mode comprised four speed patterns selected from fifty-two real-world driving datasets collected during an eco-driving test-ride event. The four patterns had the same travel distance (5.2 km, but showed varying eco-driving achievement levels. Three ICEVs, one HEV and two EVs were tested using a C/D. Good linear relationships were found between the eco-driving achievement level and electric or fuel consumption rate of all vehicles. The reduction of CO2 emissions was also estimated. The CO2-reduction rates of the four conventional (including hybrid vehicles were 10.9%–12.6%, while those of two types of EVs were 11.7%–18.4%. These results indicate that the eco-driving tips for conventional vehicles are effective to not only ICEVs and HEVs but also EVs. Furthermore, EVs have a higher potential of eco-driving effect than ICEVs and HEVs if EVs could maintain high energy conversion efficiency at low load range. This study is intended to support the importance of the dissemination of tools like the intelligent speed adaptation (ISA to obey the regulation speed in real time. In the future, also in the development and dissemination of automated driving systems, the viewpoint of achieving the traveling purpose with less kinetic energy would be important.

Driver support and automated driving systems : Acceptance and effects on behavior

NARCIS (Netherlands)

De Waard, D.; Brookhuis, K.A.; Scerbo, MW; Mouloua, M

1999-01-01

Automation in driving ranges from simple in-vehicle information systems to completely automated driving in the Automated Highway System (AHS). An increased level of automation and increased restriction in behavioural freedom, as well as decreased control over tasks, have serious consequences for

Hostility, driving anger, and dangerous driving: the emerging role of hemispheric preference.

Science.gov (United States)

Gidron, Yori; Gaygısız, Esma; Lajunen, Timo

2014-12-01

Various studies have implicated psychosocial variables (e.g., hostility) in risk of dangerous driving and traffic accidents. However, whether these variables are related to more basic neurobiological factors, and whether such associations have implications for the modification of psychosocial risk factors in the context of driving, have not been examined in depth. This study examined the relationship between hemispheric preference (HP), hostility and self-reported dangerous driving, and the ability to affect driving anger via hemisphere activating cognitive exercises (HACE). In Study 1, 254 Turkish students completed questionnaires of hostility, HP and driving behavior. In Study 2, we conducted a "proof of concept" experimental study, and tested effects of left, right and neutral HACE on driving anger, by exposing N=650 Turkish students to written scenarios including either logical (left hemisphere), visuo-spatial (right hemisphere) or "mild doses" of both types of contents (control). In Study 1, left-HP was associated with higher hostility and with more dangerous driving, and hostility mediated the relationship between L-HP and reported driving behavior. In Study 2, only right-HACE led to immediate significant reductions in self-reported driving anger. Left-HP is related to hostility and to dangerous driving, and it may be possible to partly reduce driving anger by right-HACE. Future studies must replicate these findings with objective measures, more enduring interventions and longer follow-ups. Copyright © 2014. Published by Elsevier Ltd.

Differential impact of personality traits on distracted driving behaviors in teens and older adults.

Science.gov (United States)

Parr, Morgan N; Ross, Lesley A; McManus, Benjamin; Bishop, Haley J; Wittig, Shannon M O; Stavrinos, Despina

2016-07-01

To determine the impact of personality on distracted driving behaviors. Participants included 120 drivers (48 teens, 72 older adults) who completed the 45-item Big Five Personality questionnaire assessing self-reported personality factors and the Questionnaire Assessing Distracted Driving (QUADD) assessing the frequency of distracted driving behaviors. Associations for all five personality traits with each outcome (e.g., number of times texting on the phone, talking on the phone, and interacting with the phone while driving) were analyzed separately for teens and older adults using negative binomial or Poisson regressions that controlled for age, gender and education. In teens, higher levels of openness and conscientiousness were predictive of greater reported texting frequency and interacting with a phone while driving, while lower levels of agreeableness was predictive of fewer reported instances of texting and interacting with a phone while driving. In older adults, greater extraversion was predictive of greater reported talking on and interacting with a phone while driving. Other personality factors were not significantly associated with distracted driving behaviors. Personality traits may be important predictors of distracted driving behaviors, though specific traits associated with distracted driving may vary across age groups. The relationship between personality and distracted driving behaviors provides a unique opportunity to target drivers who are more likely to engage in distracted driving behavior, thereby increasing the effectiveness of educational campaigns and improving driving safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

Combatting the Drunk Driving Problem Through Community Action: A Proposal.

Science.gov (United States)

Merki, Don; Lingg, Mary Ann

1987-01-01

Reviews efforts and accomplishments of Mothers Against Drunk Drivers movement. Identifies eight measures of state legislation and state policy concerning drunk driving and ranks each state on the measures. Offers proposal for adoption of a state agency designed to meet problem of drunk driving through administration at the local level. (Author/NB)

Drug and alcohol-impaired driving among electronic music dance event attendees.

Science.gov (United States)

Furr-Holden, Debra; Voas, Robert B; Kelley-Baker, Tara; Miller, Brenda

2006-10-15

Drug-impaired driving has received increased attention resulting from development of rapid drug-screening procedures used by police and state laws establishing per se limits for drug levels in drivers. Venues that host electronic music dance events (EMDEs) provide a unique opportunity to assess drug-impaired driving among a high proportion of young adult drug users. EMDEs are late-night dance parties marked by a substantial number of young adult attendees and elevated drug involvement. No studies to date have examined drug-impaired driving in a natural environment with active drug and alcohol users. Six EMDEs were sampled in San Diego, California, and Baltimore, Maryland. A random sample of approximately 40 attendees per event were administered surveys about alcohol and other drug (AOD) use and driving status, given breath tests for alcohol, and asked to provide oral fluid samples to test for illicit drug use upon entering and exiting the events. Driving status reduced the level of alcohol use (including abstaining) but the impact on drug-taking was not significant. However, 62% of individuals who reported their intention to drive away from the events were positive for drugs or alcohol upon leaving. This suggests that these events and settings are appropriate ones for developing interventions for reducing risks for young adults.

Neoclassical effects on RF current drive in tokamaks

International Nuclear Information System (INIS)

Yoshioka, K.; Antonsen, T.M. Jr.

1986-01-01

Neoclassical effects on RF current drive which arise because of the inhomogeneity of the magnetic field in tokamak devices are analysed. A bounce averaged 2-D Fokker-Planck equation is derived from the drift kinetic equation and is solved numerically. The model features current drive due to a strong RF wave field. The efficiency of current drive by electron cyclotron waves is significantly reduced when the waves are absorbed at the low magnetic field side of a given flux surface, whereas the efficiency remains at the same level as in the homogeneous ideal plasma when the waves are absorbed at the high field side. The efficiency of current drive by fast waves (compressional Alfven waves) with low phase velocity (vsub(parallel)/vsub(th)<1) is significantly degraded by neoclassical effects, no matter where the wave is absorbed, and the applicability of this wave seems, therefore, to be doubtful. (author)

Assessment of driving-related performance in chronic whiplash using an advanced driving simulator.

Science.gov (United States)

Takasaki, Hiroshi; Treleaven, Julia; Johnston, Venerina; Rakotonirainy, Andry; Haines, Andrew; Jull, Gwendolen

2013-11-01

Driving is often nominated as problematic by individuals with chronic whiplash associated disorders (WAD), yet driving-related performance has not been evaluated objectively. The purpose of this study was to test driving-related performance in persons with chronic WAD against healthy controls of similar age, gender and driving experience to determine if driving-related performance in the WAD group was sufficiently impaired to recommend fitness to drive assessment. Driving-related performance was assessed using an advanced driving simulator during three driving scenarios; freeway, residential and a central business district (CBD). Total driving duration was approximately 15min. Five driving tasks which could cause a collision (critical events) were included in the scenarios. In addition, the effect of divided attention (identify red dots projected onto side or rear view mirrors) was assessed three times in each scenario. Driving performance was measured using the simulator performance index (SPI) which is calculated from 12 measures. z-Scores for all SPI measures were calculated for each WAD subject based on mean values of the control subjects. The z-scores were then averaged for the WAD group. A z-score of ≤-2 indicated a driving failing grade in the simulator. The number of collisions over the five critical events was compared between the WAD and control groups as was reaction time and missed response ratio in identifying the red dots. Seventeen WAD and 26 control subjects commenced the driving assessment. Demographic data were comparable between the groups. All subjects completed the freeway scenario but four withdrew during the residential and eight during the CBD scenario because of motion sickness. All scenarios were completed by 14 WAD and 17 control subjects. Mean z-scores for the SPI over the three scenarios was statistically lower in the WAD group (-0.3±0.3; Pdriving. There were no differences in the reaction time and missed response ratio in divided

Effects of different blood alcohol concentrations and post-alcohol impairment on driving behavior and task performance.

Science.gov (United States)

Liu, Yung-Ching; Ho, Chin Heng

2010-08-01

A study using simulator methodology was conducted to investigate the effects of (1) different blood alcohol concentrations (BAC) of 0, 0.05, 0.08, and 0.10 percent and (2) post-alcohol impairment (where BAC approximately 0%) on driving behavior and subsidiary cognitive task performance. Two driving sessions were investigated, that is, drunk driving and post-alcohol driving, with each requiring approximately 20 min of driving. In addition to driving safely, participants were instructed to perform the critical flicker fusion (CFF) test and completed the NASA-TLX mental workload questionnaire. Eight licensed drivers (6 males, 2 females) participated in this 2 (road complexities) x 2 (simulated driving sessions) x 4 (levels of BAC) within-subjects experiment. The study revealed that higher BAC levels were associated with lower performing driving behavior. The driver's mental workload reached the highest values in the post-alcohol session. In terms of tasks involving divided attention, the traffic sign distance estimation showed significant deterioration with increased BAC levels. The relationship between drunk-driving behavior and alcohol dosage was supported in this study. Noticeably, no significant difference was found between drunk driving and post-alcohol driving, indicating that even in the post-alcohol situation, the impairment still remained significant enough to jeopardize traffic safety as much as it does in the case of drunk driving. In real-life situations, adopting a rest-time strategy to avoid post-alcohol impairment effects may not be the most appropriate solution by drivers; rather, drivers should be given some tests to verify the probability of post-alcohol effects on driving.

The drink driving situation in Vietnam.

Science.gov (United States)

Ngoc, Luu Bich; Thieng, Nguyen Thi; Huong, Nguyen Lan

2012-01-01

To identify the extent and nature of the problem and the main contributing factors to drink driving crashes; determine the current mechanisms in place, particularly in terms of legislation and its enforcement; and identify baseline data and relevant stakeholders. The situational assessment was based on the collection of secondary data from available reports and documents, in-depth interviews with key representatives at a central level, and field surveys in provinces. Vietnam has experienced phenomenal growth in motor vehicles, especially motorcycles, in the last decade (400%). This initially led to an increase in deaths from road crashes, but since 2006 the number has stayed fairly level according to police statistics. However, comparisons with health data suggest that the number of deaths is much higher and there are clearly a number of problems with the relevant data systems. Data on the percentage of drivers exceeding legal limits are not available, but police statistics indicated that drinking alcohol was a contributory factor in 7 percent of motor vehicle crashes. This is likely to be an underestimate, because the police and health services do not have the equipment to measure the blood alcohol concentration (BAC) levels of all drivers in crashes. Motorcycle riders and young people are in the high-risk groups. There are strict BAC limits starting at over zero and severe punishments for drunk drivers involved in serious crashes. However, the police do not have adequate manpower or equipment to conduct regular and frequent roadside checking for drivers who have been drinking. There have also been a number of education programs on road safety including drinking and driving, but these have not included sustained and intensive campaigns targeting the high-risk groups. The National Traffic Safety Committee (NTSC) is responsible for coordinating the relevant agencies but there is still a problem with lack of information sharing between agencies. This study completed

Test-retest reliability of the driving habits questionnaire in older self-driving adults.

Science.gov (United States)

Song, Chiang-Soon; Chun, Byung-Yoon; Chung, Hyun-Sook

2015-11-01

[Purpose] The purpose of this study was to investigate the test-retest reliability of the Driving Habits Questionnaire in community-dwelling older self-drivers. [Subjects and Methods] Seventy-four participants were recruited by convenience sampling from local rehabilitation centers. This was a cross-sectional study design that used two clinical measures: the Driving Habits Questionnaire and Mini-mental State Examination. To examine the test-retest reliability of the Driving Habits Questionnaire, the clinical tool was measured twice, five days apart. [Results] The Driving Habits Questionnaire showed good reliability for older community-dwelling self-drivers. The Cronbach's alpha coefficients for the four domains of dependence (0.572), difficulty (0.871), crashes and citations (0.689), and driving space (0.961) of the Driving Habits Questionnaire indicated good or high internal consistency. Driving difficulty correlated significantly with self-reported crashes and citations and driving space. [Conclusion] The results of this study suggest that the Driving Habits Questionnaire is a reliable measure of self-reported interview-based driving behavior in the community-dwelling elderly.

Safe driving for teens

Science.gov (United States)

Driving and teenagers; Teens and safe driving; Automobile safety - teenage drivers ... months before taking friends as passengers. Teenage-related driving deaths occur more often in certain conditions. OTHER SAFETY TIPS FOR TEENS Reckless driving is still a ...

Distracted Driving

Science.gov (United States)

... and increased awareness of distracted driving using radio advertisements, news stories, and similar media. After the projects ... available at www.trafficsafetymarketing.gov . Distracted Driving Enforcement – TV Ads (Paid). For re-tagging, go to: www. ...

Electrical machines & drives

CERN Document Server

Hammond, P

1985-01-01

Containing approximately 200 problems (100 worked), the text covers a wide range of topics concerning electrical machines, placing particular emphasis upon electrical-machine drive applications. The theory is concisely reviewed and focuses on features common to all machine types. The problems are arranged in order of increasing levels of complexity and discussions of the solutions are included where appropriate to illustrate the engineering implications. This second edition includes an important new chapter on mathematical and computer simulation of machine systems and revised discussions o

A study on the effects of fatigue driving and drunk driving on drivers' physical characteristics.

Science.gov (United States)

Zhang, Xingjian; Zhao, Xiaohua; Du, Hongji; Rong, Jian

2014-01-01

The purpose of this study was to analyze the effects of fatigue driving and drunk driving on drivers' physical characteristics; to analyze the differences in drivers' physical characteristics affected by different kinds of fatigue; and to compare the differences in the effects of the 2 driving states, fatigue driving and drunk driving. Twenty-five participants' physical characteristics were collected under 5 controlled situations: normal, tired driving, drowsy driving, drowsiness + tired driving, and drunk driving. In this article, fatigue driving refers to tiredness and drowsiness and includes 3 situations: tired driving, drowsy driving, and drowsiness + tired driving. The drivers' physical characteristics were measured in terms of 9 parameters: systolic blood pressure (SBP), heart rate (HR), eyesight, dynamic visual acuity (DVA), time for dark adaption (TDA), reaction time to sound (RTS), reaction time to light (RTL), deviation of depth perception (DDP), and time deviation of speed anticipation (TDSA). They were analyzed using analysis of variance (ANOVA) with repeated measures. Binary logistical regression analysis was used to explain the relationship between drivers' physical characteristics and the two driving states. Most of the drivers' physical characteristic parameters were found to be significantly different under the influence of different situations. Four indicators are significantly affected by fatigue driving during deep fatigue (in decreasing order of influence): HR, RTL, SBP and RTS. HR and RTL are significant in the logistical regression model of the drowsiness + tired driving situation and normal situations. Six indicators of the drivers' physical characteristics are significantly affected by drunk driving (in decreasing order of influence): SBP, RTL, DDP, eyesight, RTS, and TDSA. SBP and DDP have a significant effect in the logistical regression model of the drunk driving situation and the normal situation. Both fatigue driving and drunk driving

Assessment of Electron-Cyclotron-Current-Drive-Assisted Operation in DEMO

Directory of Open Access Journals (Sweden)

Marushchenko N.B.

2012-09-01

Full Text Available The achievable efficiency for external current drive through electron-cyclotron (EC waves in a demonstration tokamak reactor is discussed. Two possible reactor designs, one for steady state and one for pulsed operation, are considered. It is found that for midplane injection the achievable current drive efficiency is limited by secondharmonic absorption at levels consistent with previous studies. Propagation through the second-harmonic region can be reduced by moving the launch position to the high-field side (this can be obtained by injecting the beam from an upper port in the vacuum vessel. In this case, beam tracing calculations deliver values for the EC current drive efficiency approaching those usually reported for neutral beam current drive.

Chinese carless young drivers' self-reported driving behavior and simulated driving performance.

Science.gov (United States)

Zhang, Qian; Jiang, Zuhua; Zheng, Dongpeng; Man, Dong; Xu, Xunnan

2013-01-01

Carless young drivers refers to those drivers aged between 18 and 25 years who have a driver's license but seldom have opportunities to practice their driving skills because they do not have their own cars. Due to China's lower private car ownership, many young drivers become carless young drivers after licensure, and the safety issue associated with them has raised great concern in China. This study aims to provide initial insight into the self-reported driving behaviors and simulated driving performance of Chinese carless young drivers. Thirty-three carless young drivers and 32 young drivers with their own cars (as a comparison group) participated in this study. A modified Driver Behavior Questionnaire (DBQ) with a 4-factor structure (errors, violations, attention lapses, and memory lapses) was used to study carless young drivers' self-reported driving behaviors. A simulated driving experiment using a low-cost, fixed-base driving simulator was conducted to measure their simulated driving performance (errors, violations, attention lapses, driving maintenance, reaction time, and accidents). Self-reported DBQ outcomes showed that carless young drivers reported similar errors, more attention lapses, fewer memory lapses, and significantly fewer violation behaviors relative to young drivers with their own cars, whereas simulated driving results revealed that they committed significantly more errors, attention lapses, and violation behaviors than the comparison group. Carless young drivers had a lower ability to maintain the stability of speed and lane position, drove more cautiously approaching and passing through red traffic lights, and committed more accidents during simulated driving. A tendency to speed was not found among carless young drivers; their average speed and speeding frequency were all much lower than that of the comparison group. Lifetime mileage was the only significant predictor of carless young drivers' self-reported violations, simulated violations

Distracted driving

Science.gov (United States)

... including maps) The Dangers of Talking on the Phone While Driving You are four times more likely to get ... of reach. If you are caught using a phone while driving, you may risk a ticket or fine. Most ...

The impact of self-driving cars on existing transportation networks

Science.gov (United States)

Ji, Xiang

2018-04-01

In this paper, considering the usage of self-driving, I research the congestion problems of traffic networks from both macro and micro levels. Firstly, the macroscopic mathematical model is established using the Greenshields function, analytic hierarchy process and Monte Carlo simulation, where the congestion level is divided into five levels according to the average vehicle speed. The roads with an obvious congestion situation is investigated mainly and the traffic flow and topology of the roads are analyzed firstly. By processing the data, I propose a traffic congestion model. In the model, I assume that half of the non-self-driving cars only take the shortest route and the other half can choose the path randomly. While self-driving cars can obtain vehicle density data of each road and choose the path more reasonable. When the path traffic density exceeds specific value, it cannot be selected. To overcome the dimensional differences of data, I rate the paths by BORDA sorting. The Monte Carlo simulation of Cellular Automaton is used to obtain the negative feedback information of the density of the traffic network, where the vehicles are added into the road network one by one. I then analyze the influence of negative feedback information on path selection of intelligent cars. The conclusion is that the increase of the proportion of intelligent vehicles will make the road load more balanced, and the self-driving cars can avoid the peak and reduce the degree of road congestion. Combined with other models, the optimal self-driving ratio is about sixty-two percent. From the microscopic aspect, by using the single-lane traffic NS rule, another model is established to analyze the road Partition scheme. The self-driving traffic is more intelligent, and their cooperation can reduce the random deceleration probability. By the model, I get the different self-driving ratio of space-time distribution. I also simulate the case of making a lane separately for self-driving

Landscape heritage objects' effect on driving: a combined driving simulator and questionnaire study.

Science.gov (United States)

Antonson, Hans; Ahlström, Christer; Mårdh, Selina; Blomqvist, Göran; Wiklund, Mats

2014-01-01

According to the literature, landscape (panoramas, heritage objects e.g. landmarks) affects people in various ways. Data are primarily developed by asking people (interviews, photo sessions, focus groups) about their preferences, but to a lesser degree by measuring how the body reacts to such objects. Personal experience while driving a car through a landscape is even more rare. In this paper we study how different types of objects in the landscape affect drivers during their drive. A high-fidelity moving-base driving simulator was used to measure choice of speed and lateral position in combination with stress (heart rate measure) and eye tracking. The data were supplemented with questionnaires. Eighteen test drivers (8 men and 10 women) with a mean age of 37 were recruited. The test drivers were exposed to different new and old types of landscape objects such as 19th century church, wind turbine, 17th century milestone and bus stop, placed at different distances from the road driven. The findings are in some respect contradictory, but it was concluded that that 33% of the test drivers felt stressed during the drive. All test drivers said that they had felt calm at times during the drive but the reason for this was only to a minor degree connected with old and modern objects. The open landscape was experienced as conducive to acceleration. Most objects were, to a small degree, experienced (subjective data) as having a speed-reducing effect, much in line with the simulator data (objective data). Objects close to the road affected the drivers' choice of' lateral position. No significant differences could be observed concerning the test drivers' gaze between old or modern objects, but a significant difference was observed between the test drivers' gaze between road stretches with faraway objects and stretches without objects. No meaningful, significant differences were found for the drivers' stress levels as measured by heart rate. Copyright © 2013 Elsevier Ltd. All

Prediction of Driving Safety in Individuals with Homonymous Hemianopia and Quadrantanopia from Clinical Neuroimaging

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Michael S. Vaphiades

2014-01-01

Full Text Available Background. This study aimed to determine whether it is possible to predict driving safety of individuals with homonymous hemianopia or quadrantanopia based upon a clinical review of neuroimages that are routinely available in clinical practice. Methods. Two experienced neuroophthalmologists viewed a summary report of the CT/MRI scans of 16 participants with homonymous hemianopic or quadrantanopic field defects which indicated the site and extent of the lesion and they made predictions regarding whether participants would be safe/unsafe to drive. Driving safety was independently defined at the time of the study using state-recorded motor vehicle crashes (all crashes and at-fault for the previous 5 years and ratings of driving safety determined through a standardized on-road driving assessment by a certified driving rehabilitation specialist. Results. The ability to predict driving safety was highly variable regardless of the driving safety measure, ranging from 31% to 63% (kappa levels ranged from −0.29 to 0.04. The level of agreement between the neuroophthalmologists was only fair (kappa = 0.28. Conclusions. Clinical evaluation of summary reports of currently available neuroimages by neuroophthalmologists is not predictive of driving safety. Future research should be directed at identifying and/or developing alternative tests or strategies to better enable clinicians to make these predictions.

Prediction of driving safety in individuals with homonymous hemianopia and quadrantanopia from clinical neuroimaging.

Science.gov (United States)

Vaphiades, Michael S; Kline, Lanning B; McGwin, Gerald; Owsley, Cynthia; Shah, Ritu; Wood, Joanne M

2014-01-01

Background. This study aimed to determine whether it is possible to predict driving safety of individuals with homonymous hemianopia or quadrantanopia based upon a clinical review of neuroimages that are routinely available in clinical practice. Methods. Two experienced neuroophthalmologists viewed a summary report of the CT/MRI scans of 16 participants with homonymous hemianopic or quadrantanopic field defects which indicated the site and extent of the lesion and they made predictions regarding whether participants would be safe/unsafe to drive. Driving safety was independently defined at the time of the study using state-recorded motor vehicle crashes (all crashes and at-fault) for the previous 5 years and ratings of driving safety determined through a standardized on-road driving assessment by a certified driving rehabilitation specialist. Results. The ability to predict driving safety was highly variable regardless of the driving safety measure, ranging from 31% to 63% (kappa levels ranged from -0.29 to 0.04). The level of agreement between the neuroophthalmologists was only fair (kappa = 0.28). Conclusions. Clinical evaluation of summary reports of currently available neuroimages by neuroophthalmologists is not predictive of driving safety. Future research should be directed at identifying and/or developing alternative tests or strategies to better enable clinicians to make these predictions.

Towards functional safety in drive-by-wire vehicles

CERN Document Server

Bergmiller, Peter Johannes

2015-01-01

This book presents approaches to address key challenges based on a vehicle level view and with a special emphasis on Drive-by-Wire systems. The design and testing of modern vehicle electronics are becoming more and more demanding due to increasing interdependencies among components and the safety criticality of tasks. The development towards Drive-by-Wire functionalities in vehicles with multiple actuators for vehicle control further increases the challenge. The book explicitly takes into account the interactions between components  and aims at bridging the gap between the need to generate additional customer benefits and the effort to achieve functional safety. The book follows a twofold approach: on the one side, it presents a toolchain to support efficient further development of novel functionalities for Drive-by-Wire vehicles. The toolchain comprises appropriate software tools and scaled and full-scale experimental vehicles. On the other side, development towards functionally safe and flexible Drive-by-W...

The effects of diabetes and low blood sugar levels on driving behaviour : Comparison of diabetics and non-diabetics

NARCIS (Netherlands)

Martens, M.; Janssen, W.H.; Stork, A.

2001-01-01

Under contract with the University Medical Centre, Utrecht, TNO Human Factors has conducted research to investigate the effect of diabetes on driving behaviour. In a driving simulator experiment, patients with diabetes and non-diabetics were confronted with various trafßc situations. The subject

Control rod drives

International Nuclear Information System (INIS)

Nakamura, Akira.

1984-01-01

Purpose: To enable to monitor the coupling state between a control rod and a control rod drive. Constitution: After the completion of a control rod withdrawal, a coolant pressure is applied to a control rod drive being adjusted so as to raise only the control rod drive and, in a case where the coupling between the control rod drive and the control rod is detached, the former is elevated till it contacts the control rod and then stopped. The actual stopping position is detected by an actual position detection circuit and compared with a predetermined position stored in a predetermined position detection circuit. If both of the positions are not aligned with each other, it is judged by a judging circuit that the control rod and the control rod drives are not combined. (Sekiya, K.)

Proactive vs. reactive car driving: EEG evidence for different driving strategies of older drivers

Science.gov (United States)

Wascher, Edmund; Getzmann, Stephan

2018-01-01

Aging is associated with a large heterogeneity in the extent of age-related changes in sensory, motor, and cognitive functions. All these functions can influence the performance in complex tasks like car driving. The present study aims to identify potential differences in underlying cognitive processes that may explain inter-individual variability in driving performance. Younger and older participants performed a one-hour monotonous driving task in a driving simulator under varying crosswind conditions, while behavioral and electrophysiological data were recorded. Overall, younger and older drivers showed comparable driving performance (lane keeping). However, there was a large difference in driving lane variability within the older group. Dividing the older group in two subgroups with low vs. high driving lane variability revealed differences between the two groups in electrophysiological correlates of mental workload, consumption of mental resources, and activation and sustaining of attention: Older drivers with high driving lane variability showed higher frontal Alpha and Theta activity than older drivers with low driving lane variability and—with increasing crosswind—a more pronounced decrease in Beta activity. These results suggest differences in driving strategies of older and younger drivers, with the older drivers using either a rather proactive and alert driving strategy (indicated by low driving lane variability and lower Alpha and Beta activity), or a rather reactive strategy (indicated by high driving lane variability and higher Alpha activity). PMID:29352314

Simple Driving Techniques

DEFF Research Database (Denmark)

Rosendahl, Mads

2002-01-01

-like language. Our aim is to extract a simple notion of driving and show that even in this tamed form it has much of the power of more general notions of driving. Our driving technique may be used to simplify functional programs which use function composition and will often be able to remove intermediate data...

Policy challenges of increasing automation in driving

Directory of Open Access Journals (Sweden)

Ata M. Khan

2012-03-01

Full Text Available The convergence of information and communication technologies (ICT with automotive technologies has already resulted in automation features in road vehicles and this trend is expected to continue in the future owing to consumer demand, dropping costs of components, and improved reliability. While the automation features that have taken place so far are mainly in the form of information and driver warning technologies (classified as level I pre-2010, future developments in the medium term (level II 2010–2025 are expected to exhibit connected cognitive vehicle features and encompass increasing degree of automation in the form of advanced driver assistance systems. Although autonomous vehicles have been developed for research purposes and are being tested in controlled driving missions, the autonomous driving case is only a long term (level III 2025+ scenario. This paper contributes knowledge on technological forecasts regarding automation, policy challenges for each level of technology development and application context, and the essential instrument of cost-effectiveness for policy analysis which enables policy decisions on the automation systems to be assessed in a consistent and balanced manner. The cost of a system per vehicle is viewed against its effectiveness in meeting policy objectives of improving safety, efficiency, mobility, convenience and reducing environmental effects. Example applications are provided that illustrate the contribution of the methodology in providing information for supporting policy decisions. Given the uncertainties in system costs as well as effectiveness, the tool for assessing policies for future generation features probabilistic and utility-theoretic analysis capability. The policy issues defined and the assessment framework enable the resolution of policy challenges while allowing worthy innovative automation in driving to enhance future road transportation.

Installing and detaching apparatus for a control rod drive mechanism

International Nuclear Information System (INIS)

Akimoto, Seiichi; Watanabe, Mitsuhiro; Yoshida, Tomiharu; Sugaya, Jun-ichi; Saito, Takashi.

1976-01-01

Object: To facilitate maintenance and repair of a control rod drive mechanism. Structure: The apparatus comprises a means moving in a moving direction of a control rod within a reactor vessel, said moving means having a housing mounted thereon, a means mounted on the reactor vessel to release a connection between a control rod drive mechanism connected to the control rod and the control rod, and a means for mounting and removing a fixing means which connects the reactor vessel to the control rod drive means. With this arrangement, cooling water of high radioactivity level may not be leaked outside to thereby notably reduce dangerousness of exposure and materially cut time required for mounting and removing the control rod drive mechanism. (Ohara, T.)

Driving and dementia: Efficient approach to driving safety concerns in family practice.

Science.gov (United States)

Lee, Linda; Molnar, Frank

2017-01-01

To provide primary care physicians with an approach to driving safety concerns when older persons present with memory difficulties. The approach is based on an accredited memory clinic training program developed by the Centre for Family Medicine Primary Care Collaborative Memory Clinic. One of the most challenging aspects of dementia care is the assessment of driving safety. Drivers with dementia are at higher risk of motor vehicle collisions, yet many drivers with mild dementia might be safely able to continue driving for several years. Because safe driving is dependent on multiple cognitive and functional skills, clinicians should carefully consider many factors when determining if cognitive concerns affect driving safety. Specific findings on corroborated history and office-based cognitive testing might aid in the physician's decisions to refer for comprehensive on-road driving evaluation and whether to notify transportation authorities in accordance with provincial reporting requirements. Sensitive communication and a person-centred approach are essential. Primary care physicians must consider many factors when determining if cognitive concerns might affect driving safety in older drivers. Copyright© the College of Family Physicians of Canada.

Effect of police mobile computer terminal interface design on officer driving distraction.

Science.gov (United States)

Zahabi, Maryam; Kaber, David

2018-02-01

Several crash reports have identified in-vehicle distraction to be a primary cause of emergency vehicle crashes especially in law enforcement. Furthermore, studies have found that mobile computer terminals (MCTs) are the most frequently used in-vehicle technology for police officers. Twenty police officers participated in a driving simulator-based assessment of visual behavior, performance, workload and situation awareness with current and enhanced MCT interface designs. In general, results revealed MCT use while driving to decrease officer visual attention to the roadway, but usability improvements can reduce the level of visual distraction and secondary-task completion time. Results also suggest that use of MCTs while driving significantly reduces perceived level of driving environment awareness for police officers and increases cognitive workload. These findings may be useful for MCT manufacturers in improving interface designs to increase police officer and civilian safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

The behavioral economics of driving after drinking among college drinkers.

Science.gov (United States)

Teeters, Jenni B; Murphy, James G

2015-05-01

Driving after drinking (DAD) among college students is a significant public health concern, yet little is known about specific theoretical risk factors for DAD, beyond drinking level, among college student drinkers. This study had the following aims: (i) to examine the associations between elevated alcohol demand and DAD, (ii) to determine whether demand decreases in response to a hypothetical driving scenario, (iii) to determine whether drivers who report DAD in the past 3 months would show less of a reduction in demand in response to the hypothetical driving scenario, and (iv) to determine whether delayed reward discounting (DRD) is associated with DAD. Participants were 419 college students who reported at least 1 day of past-month alcohol use. Participants completed 2 alcohol purchase tasks (APTs) that assessed hypothetical alcohol consumption across 17 drink prices with and without a driving scenario, a delay-discounting task, and a series of questions regarding DAD. In logistic regression models that controlled for drinking level, demographics, and sensation seeking, participants reporting higher demand intensity (95% confidence interval [95% CI] [1.04, 2.34]), breakpoint (95% CI [1.23, 2.28]), Omax (95% CI [1.03, 1.53]), and lower elasticity (95% CI [0.15, 1.02]) were more likely to report DAD. Additionally, in analyses of covariance, DAD(+) participants exhibited significantly less of a reduction in demand between the standard and the driving APT (intensity, p demand and less sensitivity to a hypothetical driving scenario. Drinkers with elevated demand should be prioritized for DAD intervention efforts. Copyright © 2015 by the Research Society on Alcoholism.

The relationship between impaired driving crashes and beliefs about impaired driving: do residents in high crash rate counties have greater concerns about impaired driving?

Science.gov (United States)

Beck, Kenneth H; Yan, Alice F; Wang, Min Qi; Kerns, Timothy J; Burch, Cynthia A

2009-04-01

The purpose of this investigation was to examine the relationship between impaired driving crashes and public beliefs and concerns about impaired driving across each of Maryland's twenty-four counties (including Baltimore City). It was hypothesized that residents of counties that experience higher impaired driving crashes would express more concerns about impaired driving and perceive more risks about driving impaired than residents of counties that have lower rates of impaired driving. Data for alcohol impaired driving crashes were obtained for the years 2004-2006. These data were compared to public opinion data that was obtained annually by random-digit-dial telephone surveys from 2004 to 2007. Concerns about drunk driving as well as perceptions of the likelihood of being stopped by the police if one were to drive after having too much to drink were related to counties with higher serious impaired driving crash rates, as were perceptions that the police and the legal system were too lenient. Perceptions about the likelihood of being stopped by the police were higher in those counties with more impaired driving enforcement activity. Perceptions of concern appear to be shaped more by crash exposure than enforcement activity. Campaigns that address impaired driving prevention should substantially increase enforcement, strengthen the adjudication process of impaired drivers, and emphasize the potential seriousness of drinking-driving crashes in their promotional activities.

Contributions of physical and cognitive impairments to self-reported driving difficulty in chronic whiplash-associated disorders.

Science.gov (United States)

Takasaki, Hiroshi; Treleaven, Julia; Johnston, Venerina; Jull, Gwendolen

2013-08-15

Cross-sectional. To conduct a preliminary analysis of the physical, cognitive, and psychological domains contributing to self-reported driving difficulty after adjusting for neck pain, dizziness, and relevant demographics in chronic whiplash-associated disorders (WAD) using hierarchical regression modeling. Pain is a risk factor for car crashes, and dizziness may affect fitness to drive. Both symptoms are common in chronic WAD and difficulty driving is a common complaint in this group. Chronic WAD is often accompanied by physical, cognitive, and psychological impairments. These impairments may contribute to self-reported driving difficulty beyond neck pain, dizziness, and relevant demographics. Forty individuals with chronic WAD participated. Dependent variables were the magnitude of self-reported driving difficulty assessed in the strategic, tactical, and operational levels of the Neck Pain Driving Index. Three models were developed to assess the contributions of independent variables (physical, cognitive, and psychological domains) to each of the 3 dependent variables after adjusting for neck pain intensity, dizziness, and driving demographics. The measures included were: physical domain-range and maximum speed of head rotation, performances during gaze stability, eye-head coordination, and visual dependency tests; cognitive domain-self-reported cognitive symptoms including fatigue and the trail making tests; and psychological domain-general stress, traumatic stress, depression, and fear of neck movements and driving. Symptom duration was relevant to driving difficulty in the strategic and tactical levels. The cognitive domain increased statistical power to estimate the strategic and operational levels (P < 0.1) beyond other contributors. The physical domain increased statistical power to estimate the tactical level (P < 0.1) beyond other contributors. Physical and cognitive impairments independently contributed to self-reported driving difficulty in chronic WAD

Drinking and Driving among Recent Latino Immigrants: The Impact of Neighborhoods and Social Support

Directory of Open Access Journals (Sweden)

Mariana Sanchez

2016-10-01

Full Text Available Latinos are disproportionately impacted by drinking and driving arrests and alcohol-related fatal crashes. Why, and how, these disparities occur remains unclear. The neighborhood environments that recent Latino immigrants encounter in their host communities can potentially influence health behaviors over time, including the propensity to engage in drinking and driving. This cross-sectional study utilizes a sample of 467 documented and undocumented adult recent Latino immigrants in the United States to answer the following research questions: (a How do neighborhood-level factors, combined with social support, impact drinking and driving risk behaviors?; and (b Does acculturative stress moderate the effects of those associations? Results indicate neighborhood-level factors (informal social control and social capital have protective effects against drinking and driving risk behaviors via the mediating mechanism of social support. Acculturative stress moderated associations between neighborhood informal social control and social support, whereby the protective effects of informal social control on social support were not present for those immigrants with higher levels of acculturative stress. Our findings contribute to the limited knowledge of drinking and driving among Latino immigrants early in the immigration process and suggest that, in the process of developing prevention programs tailored to Latino immigrants, greater attention must be paid to neighborhood-level factors.

Drinking and Driving among Recent Latino Immigrants: The Impact of Neighborhoods and Social Support

Science.gov (United States)

Sanchez, Mariana; Romano, Eduardo; Dawson, Christyl; Huang, Hui; Sneij, Alicia; Cyrus, Elena; Rojas, Patria; Cano, Miguel Ángel; Brook, Judith; De La Rosa, Mario

2016-01-01

Latinos are disproportionately impacted by drinking and driving arrests and alcohol-related fatal crashes. Why, and how, these disparities occur remains unclear. The neighborhood environments that recent Latino immigrants encounter in their host communities can potentially influence health behaviors over time, including the propensity to engage in drinking and driving. This cross-sectional study utilizes a sample of 467 documented and undocumented adult recent Latino immigrants in the United States to answer the following research questions: (a) How do neighborhood-level factors, combined with social support, impact drinking and driving risk behaviors?; and (b) Does acculturative stress moderate the effects of those associations? Results indicate neighborhood-level factors (informal social control and social capital) have protective effects against drinking and driving risk behaviors via the mediating mechanism of social support. Acculturative stress moderated associations between neighborhood informal social control and social support, whereby the protective effects of informal social control on social support were not present for those immigrants with higher levels of acculturative stress. Our findings contribute to the limited knowledge of drinking and driving among Latino immigrants early in the immigration process and suggest that, in the process of developing prevention programs tailored to Latino immigrants, greater attention must be paid to neighborhood-level factors. PMID:27801856

Is drive for muscularity related to body checking behaviors in men athletes?

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Leonardo de Sousa Fortes

Full Text Available Abstract The aim of this study was to analyze the relationship between drive for muscularity and body checking behaviors in men athletes. Two hundred and twelve Brazilian athletes over 15 years of age participated. We used the Drive for Muscularity Scale (DMS to evaluate the drive for muscularity. The Male Body Checking Questionnaire was used to assess body checking behaviors. The findings demonstrated a relationship between the "body image-oriented muscularity" subscale of the DMS and body checking behaviors (p = 0.001. The results indicated differences in body checking among athletes with high and low levels of drive for muscularity. We concluded that drive for muscularity was related to body checking behaviors in men athletes.

Dangerous driving in a Chinese sample: associations with morningness-eveningness preference and personality.

Science.gov (United States)

Qu, Weina; Ge, Yan; Xiong, Yuexin; Carciofo, Richard; Zhao, Wenguo; Zhang, Kan

2015-01-01

Individual differences in morningness-eveningness preference may influence susceptibility and response to sleepiness. These differences could influence driving performance, but the influence of morningness-eveningness preference on driving behavior and accident risk has not been comprehensively studied. As morningness-eveningness preference is associated with personality characteristics, we also investigated how the interaction between morningness-eveningness preference and personality may be related to dangerous driving behaviors. Two hundred and ninety five drivers completed the reduced Morningness-Eveningness Questionnaire, the Dula Dangerous Driving Index, and personality scales for agreeableness, conscientiousness and neuroticism, and reported demographic information (gender, age, level of education, driving years and annual average driving mileage) and self-reported traffic violations (accidents, penalty points and fines). The results showed that more Risky Driving, Aggressive Driving, Negative Cognitive/Emotional Driving and Drunk Driving, as measured by the Dula Dangerous Driving Index, were all significantly correlated with more eveningness, corresponding to lower scores on the reduced Morningness-Eveningness Questionnaire. Moreover, eveningness was correlated with self-reported traffic accidents, penalty points and fines. Furthermore, a moderation effect was found: eveningness was more strongly associated with risky driving and negative emotional driving in those who scored high for trait agreeableness.

Dangerous driving in a Chinese sample: associations with morningness-eveningness preference and personality.

Directory of Open Access Journals (Sweden)

Weina Qu

Full Text Available Individual differences in morningness-eveningness preference may influence susceptibility and response to sleepiness. These differences could influence driving performance, but the influence of morningness-eveningness preference on driving behavior and accident risk has not been comprehensively studied. As morningness-eveningness preference is associated with personality characteristics, we also investigated how the interaction between morningness-eveningness preference and personality may be related to dangerous driving behaviors. Two hundred and ninety five drivers completed the reduced Morningness-Eveningness Questionnaire, the Dula Dangerous Driving Index, and personality scales for agreeableness, conscientiousness and neuroticism, and reported demographic information (gender, age, level of education, driving years and annual average driving mileage and self-reported traffic violations (accidents, penalty points and fines. The results showed that more Risky Driving, Aggressive Driving, Negative Cognitive/Emotional Driving and Drunk Driving, as measured by the Dula Dangerous Driving Index, were all significantly correlated with more eveningness, corresponding to lower scores on the reduced Morningness-Eveningness Questionnaire. Moreover, eveningness was correlated with self-reported traffic accidents, penalty points and fines. Furthermore, a moderation effect was found: eveningness was more strongly associated with risky driving and negative emotional driving in those who scored high for trait agreeableness.

Nuclear refueling platform drive system

International Nuclear Information System (INIS)

Busch, F.R.; Faulstich, D.L.

1992-01-01

This patent describes a drive system. It comprises: a gantry including a bridge having longitudinal and transverse axes and supported by spaced first and second end frames joined to fist and second end frames joined to first and second drive trucks for moving the bridge along the transverse axis; first means for driving the first drive truck; second means for driving the second drive truck being independent from the first driving means; and means for controlling the first and second driving means for reducing differential transverse travel between the first and second drive trucks, due to a skewing torque acting on the bridge, to less than a predetermined maximum, the controlling means being in the form of an electrical central processing unit and including: a closed-loop first velocity control means for controlling velocity of the first drive truck by providing a first command signal to the first driver means; a close loop second velocity control means for controlling velocity of the second drive truck by providing a second command signal to the second driving means; and an auxiliary closed-loop travel control means

Tuning CRISPR-Cas9 Gene Drives in Saccharomyces cerevisiae

Science.gov (United States)

Roggenkamp, Emily; Giersch, Rachael M.; Schrock, Madison N.; Turnquist, Emily; Halloran, Megan; Finnigan, Gregory C.

2018-01-01

Control of biological populations is an ongoing challenge in many fields, including agriculture, biodiversity, ecological preservation, pest control, and the spread of disease. In some cases, such as insects that harbor human pathogens (e.g., malaria), elimination or reduction of a small number of species would have a dramatic impact across the globe. Given the recent discovery and development of the CRISPR-Cas9 gene editing technology, a unique arrangement of this system, a nuclease-based “gene drive,” allows for the super-Mendelian spread and forced propagation of a genetic element through a population. Recent studies have demonstrated the ability of a gene drive to rapidly spread within and nearly eliminate insect populations in a laboratory setting. While there are still ongoing technical challenges to design of a more optimal gene drive to be used in wild populations, there are still serious ecological and ethical concerns surrounding the nature of this powerful biological agent. Here, we use budding yeast as a safe and fully contained model system to explore mechanisms that might allow for programmed regulation of gene drive activity. We describe four conserved features of all CRISPR-based drives and demonstrate the ability of each drive component—Cas9 protein level, sgRNA identity, Cas9 nucleocytoplasmic shuttling, and novel Cas9-Cas9 tandem fusions—to modulate drive activity within a population. PMID:29348295

Dementia and driving.

Science.gov (United States)

O'Neill, D; Neubauer, K; Boyle, M; Gerrard, J; Surmon, D; Wilcock, G K

1992-04-01

Many European countries test cars, but not their drivers, as they age. There is evidence to suggest that human factors are more important than vehicular factors as causes of motor crashes. The elderly also are involved in more accidents per distance travelled than middle-aged drivers. As the UK relies on self-certification of health by drivers over the age of 70 years, we examined the driving practices of patients with dementia attending a Memory Clinic. Nearly one-fifth of 329 patients with documented dementia continued to drive after the onset of dementia, and impaired driving ability was noted in two-thirds of these. Their families experienced great difficulty in persuading patients to stop driving, and had to invoke outside help in many cases. Neuropsychological tests did not help to identify those who drove badly while activity of daily living scores were related to driving ability. These findings suggest that many patients with dementia drive in an unsafe fashion after the onset of the illness. The present system of self-certification of health by the elderly for driver-licensing purposes needs to be reassessed.

Dialling and driving: factors influencing intentions to use a mobile phone while driving.

Science.gov (United States)

Walsh, Shari P; White, Katherine M; Hyde, Melissa K; Watson, Barry

2008-11-01

Despite being identified as an unsafe (and, in some jurisdictions, illegal) driving practice, the psychological factors underlying people's decision to use their mobile phone while driving have received little attention. The present study utilised the theory of planned behaviour (TPB) to examine the role of attitudes, norms, control factors, and risk perceptions, in predicting people's intentions to use their mobile phone while driving. We examined the predictors of intentions to use a mobile phone while driving in general, and for calling and text messaging in 4 scenarios differing in descriptions of vehicle speed and time pressure. There was some support for the TPB given that attitudes consistently predicted intentions to drive while using a mobile phone and that pressure from significant others (norms) determined some phone use while driving intentions, although less support was found for the role of perceptions of control. Risk was not generally predictive of safer driving intentions. These findings indicate that different factors influence each form of mobile phone use while driving and, hence, a multi-strategy approach is likely to be required to address the issue.

Relationships between frequency of driving under the influence of cannabis, self-reported reckless driving and risk-taking behavior observed in a driving simulator.

Science.gov (United States)

Bergeron, Jacques; Paquette, Martin

2014-06-01

The role of cannabis consumption in traffic crashes is unclear and the causal link between cannabis and collisions is still to be demonstrated. While cannabis use is very likely to impair driving ability, there is as yet no overwhelming evidence that cannabis use in isolation contributes more to collisions than other characteristics inherent to cannabis users. As noted in a growing body of literature, individuals driving under the influence of cannabis (DUIC) seem to exhibit a general reckless driving style putting them at higher risk to be involved in traffic crashes. This study aims at investigating the relationship between self-reported DUIC and reckless driving by means of self-reported measures and direct observations made in a driving simulator. Participants (n=72) were required to be between 18 and 25 years of age, to hold a valid driver's license, and to drive at least twice a week. They completed standard driving simulation tasks recreating everyday on-road trivial conditions. Results show that people admitting that they commit more real-life dangerous driving behaviors reached higher maximum speed and demonstrated more reckless driving behaviors on the driving simulation tasks. Self-reported DUIC is associated with a risky driving style including a broad range of reckless on-road behaviors and support the problem driving behavior theory. Moreover, beyond confounding factors, both self-report DUIC and observed dangerous behaviors are associated with real-life traffic violations. Since DUIC appears to be related to an overall reckless style of driving, it is proposed that public safety policies should be more holistic, simultaneously targeting multiple on-road dangerous behaviors for intervention. Copyright © 2014 Elsevier B.V. All rights reserved.

Cognitive impairment and driving safety.

Science.gov (United States)

Eby, David W; Molnar, Lisa J

2012-11-01

As the populations of many countries continue to age, cognitive impairment will likely become more common. Individuals with cognitive impairment pose special challenges for families, health professionals, driving safety professionals, and the larger community, particularly if these older adults depend on driving as their primary means of community mobility. It is vital that we continue to extend our knowledge about the driving behavior of individuals' with cognitive impairment, as well as try to develop effective means of screening and assessing these individuals for fitness to drive and help facilitate their transition to non-driving when appropriate. This special issue is intended to provide researchers and practitioners an opportunity to present the most recent research findings on driving-related issues among older adults with cognitive impairment. The issue contains 11 original contributions from seven countries. The topics covered by these papers are: crash risks; screening, assessment, and fitness to drive; driving performance using a driving simulator; and driving behaviors and driving-related decisions of people with cognitive impairments. Copyright © 2012. Published by Elsevier Ltd.

State all-driver distracted driving laws and high school students'  texting while driving behavior.

Science.gov (United States)

Qiao, Nan; Bell, Teresa Maria

2016-01-01

Texting while driving is highly prevalent among adolescents and young adults in the United States. Texting while driving can significantly increase the risk of road crashes and is associated with other risky driving behaviors. Most states have enacted distracted driving laws to prohibit texting while driving. This study examines effects of different all-driver distracted driving laws on texting while driving among high school students. High school student data were extracted from the 2013 National Youth Risk Behavior Survey. Distracted driving law information was collected from the National Conference of State Legislatures. The final sample included 6,168 high school students above the restricted driving age in their states and with access to a vehicle. Logistic regression was applied to estimate odds ratios of laws on texting while driving. All-driver text messaging bans with primary enforcement were associated with a significant reduction in odds of texting while driving among high school students (odds ratio = 0.703; 95% confidence interval, 0.513-0.964), whereas all-driver phone use bans with primary enforcement did not have a significant association with texting while driving (odds ratio = 0.846; 95% confidence interval, 0.501-1.429). The findings indicate that all-driver distracted driving laws that specifically target texting while driving as opposed to all types of phone use are effective in reducing the behavior among high school students.

Using driving simulators to assess driving safety.

Science.gov (United States)

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.

Electron-cyclotron current drive in the tokamak physics experiment

International Nuclear Information System (INIS)

Smith, G.R.; Kritz, A.H.; Radin, S.H.

1992-01-01

Ray-tracking calculations provide estimates of the electron-cyclotron heating (ECH) power required to suppress tearing modes near the q=2 surface in the Tokamak Physics Experiment. Effects of finite beam width and divergence are included, as are the effects of scattering of the ECH power by drift-wave turbulence. A frequency of about 120 GHz allows current drive on the small-R (high-B) portion of q=2, while 80 GHz drives current on the large-R (low-B) portion. The higher frequency has the advantages of less sensitivity to wave and plasma parameters and of no trapped-electron degradation of current-drive efficiency. Less than 1 MW suffices to suppress tearing modes even with high turbulence levels

The Technique of Changing the Drive Method of Micro Step Drive and Sensorless Drive for Hybrid Stepping Motor

Science.gov (United States)

Yoneda, Makoto; Dohmeki, Hideo

The position control system with the advantage large torque, low vibration, and high resolution can be obtained by the constant current micro step drive applied to hybrid stepping motor. However loss is large, in order not to be concerned with load torque but to control current uniformly. As the one technique of a position control system in which high efficiency is realizable, the same sensorless control as a permanent magnet motor is effective. But, it was the purpose that the control method proposed until now controls speed. Then, this paper proposed changing the drive method of micro step drive and sensorless drive. The change of the drive method was verified from the simulation and the experiment. On no load, it was checked not producing change of a large speed at the time of a change by making electrical angle and carrying out zero reset of the integrator. On load, it was checked that a large speed change arose. The proposed system could change drive method by setting up the initial value of an integrator using the estimated result, without producing speed change. With this technique, the low loss position control system, which employed the advantage of the hybrid stepping motor, has been built.

Study on anti-seismic test of control rod driving system suspended by magnetic force

International Nuclear Information System (INIS)

Zhang Zhihua; Qian Dazhi; Xu Xianqi; Huang Hongwen; Zhang Zhengming; Wu Xinxin; Hu Xiao

2012-01-01

To verify the stability, reliability and security function in extreme conditions, the anti-seismic test of control rod drive line was conducted. Drop-time of control rod drive line in different earthquake intensities was got. The response and strain values of control rod drive line acceleration on SL-1, SL-2 level were measured. Safety functions of control rod drive line were validated in different work conditions. Anti-seismic test data shows that the driving system can keep the structure's integrality and realize operation function under OBE and SSE. (authors)

Optical pulse characteristics of sonoluminescence at low acoustic drive levels

Science.gov (United States)

Arakeri, Vijay H.; Giri, Asis

2001-06-01

From a nonaqueous alkali-metal salt solution, it is possible to observe sonoluminescence (SL) at low acoustic drive levels with the ratio of the acoustic pressure amplitude to the ambient pressure being about 1. In this case, the emission has a narrowband spectral content and consists of a few flashes of light from a levitated gas bubble going through an unstable motion. A systematic statistical study of the optical pulse characteristics of this form of SL is reported here. The results support our earlier findings [Phys. Rev. E 58, R2713 (1998)], but in addition we have clearly established a variation in the optical pulse duration with certain physical parameters such as the gas thermal conductivity. Quantitatively, the SL optical pulse width is observed to vary from 10 ns to 165 ns with the most probable value being 82 ns, for experiments with krypton-saturated sodium salt ethylene glycol solution. With argon, the variation is similar to that of krypton but the most probable value is reduced to 62 ns. The range is significantly smaller with helium, being from 22 ns to 65 ns with the most probable value also being reduced to 42 ns. The observed large variation, for example with krypton, under otherwise fixed controllable experimental parameters indicates that it is an inherent property of the observed SL process, which is transient in nature. It is this feature that necessitated our statistical study. Numerical simulations of the SL process using the bubble dynamics approach of Kamath, Prosperetti, and Egolfopoulos [J. Acoust. Soc. Am. 94, 248 (1993)] suggest that a key uncontrolled parameter, namely the initial bubble radius, may be responsible for the observations. In spite of the fact that certain parameters in the numerical computations have to be fixed from a best fit to one set of experimental data, the observed overall experimental trends of optical pulse characteristics are predicted reasonably well.

Optical pulse characteristics of sonoluminescence at low acoustic drive levels

International Nuclear Information System (INIS)

Arakeri, Vijay H.; Giri, Asis

2001-01-01

From a nonaqueous alkali-metal salt solution, it is possible to observe sonoluminescence (SL) at low acoustic drive levels with the ratio of the acoustic pressure amplitude to the ambient pressure being about 1. In this case, the emission has a narrowband spectral content and consists of a few flashes of light from a levitated gas bubble going through an unstable motion. A systematic statistical study of the optical pulse characteristics of this form of SL is reported here. The results support our earlier findings [Phys. Rev. E >58, R2713 (1998)], but in addition we have clearly established a variation in the optical pulse duration with certain physical parameters such as the gas thermal conductivity. Quantitatively, the SL optical pulse width is observed to vary from 10 ns to 165 ns with the most probable value being 82 ns, for experiments with krypton-saturated sodium salt ethylene glycol solution. With argon, the variation is similar to that of krypton but the most probable value is reduced to 62 ns. The range is significantly smaller with helium, being from 22 ns to 65 ns with the most probable value also being reduced to 42 ns. The observed large variation, for example with krypton, under otherwise fixed controllable experimental parameters indicates that it is an inherent property of the observed SL process, which is transient in nature. It is this feature that necessitated our statistical study. Numerical simulations of the SL process using the bubble dynamics approach of Kamath, Prosperetti, and Egolfopoulos [J. Acoust. Soc. Am. >94, 248 (1993)] suggest that a key uncontrolled parameter, namely the initial bubble radius, may be responsible for the observations. In spite of the fact that certain parameters in the numerical computations have to be fixed from a best fit to one set of experimental data, the observed overall experimental trends of optical pulse characteristics are predicted reasonably well

Subwavelength position measurements with running-wave driving fields

Energy Technology Data Exchange (ETDEWEB)

Evers, Joerg [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Qamar, Sajid [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Centre for Quantum Physics, COMSATS Institute of Information Technology, Islamabad (Pakistan)

2011-08-15

Subwavelength position measurement of quantum particles is discussed. Our setup is based on a closed-loop driving-field configuration, which enforces a sensitivity of the particle dynamics to the phases of the applied fields. Thus, running wave fields are sufficient, avoiding limitations associated with standing-wave-based localization schemes. Reversing the directions of the driving laser fields switches between different magnification levels for the position determination. This allows us to optimize the localization, and at the same time eliminates the need for additional classical measurements common to all previous localization schemes based on spatial periodicity.

Mobile phone use while driving: a hybrid modeling approach.

Science.gov (United States)

Márquez, Luis; Cantillo, Víctor; Arellana, Julián

2015-05-01

The analysis of the effects that mobile phone use produces while driving is a topic of great interest for the scientific community. There is consensus that using a mobile phone while driving increases the risk of exposure to traffic accidents. The purpose of this research is to evaluate the drivers' behavior when they decide whether or not to use a mobile phone while driving. For that, a hybrid modeling approach that integrates a choice model with the latent variable "risk perception" was used. It was found that workers and individuals with the highest education level are more prone to use a mobile phone while driving than others. Also, "risk perception" is higher among individuals who have been previously fined and people who have been in an accident or almost been in an accident. It was also found that the tendency to use mobile phones while driving increases when the traffic speed reduces, but it decreases when the fine increases. Even though the urgency of the phone call is the most important explanatory variable in the choice model, the cost of the fine is an important attribute in order to control mobile phone use while driving. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sustained climate warming drives declining marine biological productivity

Science.gov (United States)

Moore, J. Keith; Fu, Weiwei; Primeau, Francois; Britten, Gregory L.; Lindsay, Keith; Long, Matthew; Doney, Scott C.; Mahowald, Natalie; Hoffman, Forrest; Randerson, James T.

2018-03-01

Climate change projections to the year 2100 may miss physical-biogeochemical feedbacks that emerge later from the cumulative effects of climate warming. In a coupled climate simulation to the year 2300, the westerly winds strengthen and shift poleward, surface waters warm, and sea ice disappears, leading to intense nutrient trapping in the Southern Ocean. The trapping drives a global-scale nutrient redistribution, with net transfer to the deep ocean. Ensuing surface nutrient reductions north of 30°S drive steady declines in primary production and carbon export (decreases of 24 and 41%, respectively, by 2300). Potential fishery yields, constrained by lower–trophic-level productivity, decrease by more than 20% globally and by nearly 60% in the North Atlantic. Continued high levels of greenhouse gas emissions could suppress marine biological productivity for a millennium.

High-risk driving attitudes and everyday driving violations of car and racing enthusiasts in Ontario, Canada.

Science.gov (United States)

Yildirim-Yenier, Zümrüt; Vingilis, Evelyn; Wiesenthal, David L; Mann, Robert E; Seeley, Jane

2015-01-01

Attitudes and individual difference variables of car and racing enthusiasts regarding high-risk behaviors of street racing and stunt driving have recently been investigated. Positive attitudes toward high-risk driving, personality variables such as driver thrill seeking, and other self-reported risky driving acts were associated with these behaviors. However, probable relationships among high-risk driving tendencies, everyday driving behaviors, and negative road safety outcomes have remained largely unexamined. This study aimed to investigate the associations among car and racing enthusiasts' high-risk driving attitudes, self-reported everyday driving violations (i.e., ordinary and aggressive violations), and self-reported negative outcomes (i.e., collisions and driving offense citations). A web-based survey was conducted with members and visitors of car club and racing websites in Ontario, Canada. Data were obtained from 366 participants. The questionnaire included 4 attitude measures-(1) attitudes toward new penalties for Ontario's Street Racers, Stunt and Aggressive Drivers Legislation; (2) attitudes toward new offenses of stunt driving under the same legislation; (3) general attitudes toward street racing and stunt driving; (4) comparison of street racing with other risky driving behaviors-self-reported driving violations (i.e., ordinary and aggressive violations); self-reported collisions and offense citations; and background and driving questions (e.g., age, driving frequency). Results revealed that attitudes toward stunt driving offenses negatively and general attitudes toward street racing and stunt driving positively predicted ordinary violations, which, in turn, predicted offense citations. Moreover, general attitudes toward street racing and stunt driving positively predicted aggressive violations, which, in turn, predicted offense citations. The findings indicate that positive high-risk driving attitudes may be transferring to driving violations in

Parkinson's disease and driving ability

Science.gov (United States)

Singh, Rajiv; Pentland, Brian; Hunter, John; Provan, Frances

2007-01-01

Objectives To explore the driving problems associated with Parkinson's disease (PD) and to ascertain whether any clinical features or tests predict driver safety. Methods The driving ability of 154 individuals with PD referred to a driving assessment centre was determined by a combination of clinical tests, reaction times on a test rig and an in‐car driving test. Results The majority of cases (104, 66%) were able to continue driving although 46 individuals required an automatic transmission and 10 others needed car modifications. Ability to drive was predicted by the severity of physical disease, age, presence of other associated medical conditions, particularly dementia, duration of disease, brake reaction, time on a test rig and score on a driving test (all pautomatic transmission. A combination of clinical tests and in‐car driving assessment will establish safety to drive, and a number of clinical correlates can be shown to predict the likely outcome and may assist in the decision process. This is the largest series of consecutive patients seen at a driving assessment centre reported to date, and the first to devise a scoring system for on‐road driving assessment. PMID:17178820

A Transformerless Medium Voltage Multiphase Motor Drive System

Directory of Open Access Journals (Sweden)

Dan Wang

2016-04-01

Full Text Available A multiphase motor has several major advantages, such as high reliability, fault tolerance, and high power density. It is a critical issue to develop a reliable and efficient multiphase motor drive system. In this paper, a transformerless voltage source converter-based drive system for a medium-voltage (MV multiphase motor is proposed. This drive converter employs cascaded H-bridge rectifiers loaded by H-bridge inverters as the interface between the grid and multiphase motor. The cascaded H-bridge rectifier technique makes the drive system able to be directly connected to the MV grid without the phase-shifting transformer because it can offset the voltage level gap between the MV grid and the semiconductor devices, provide near-sinusoidal AC terminal voltages without filters, and draw sinusoidal line current from the grid. Based on a digital signal processor (DSP, a complete improved Phase Disposition Pulse Width Modulation (PD-PWM method is developed to ensure the individual DC-link capacitor voltage balancing for enhancing the controllability and limiting the voltage and power stress on the H-bridge cells. A downscaled prototype is designed and developed based on a nine-phase motor. The experimental results verify the excellent performances of the proposed drive system and control strategy in steady-state and variant-frequency startup operations.

Rod drive and latching mechanism

International Nuclear Information System (INIS)

Veronesi, L.; Sherwood, D.G.

1982-01-01

Hydraulic drive and latching mechanisms for driving reactivity control mechanisms in nuclear reactors are described. Preferably, the pressurized reactor coolant is utilized to raise the drive rod into contact with and to pivot the latching mechanism so as to allow the drive rod to pass the latching mechanism. The pressure in the housing may then be equalized which allows the drive rod to move downwardly into contact with the latching mechanism but to hold the shaft in a raised position with respect to the reactor core. Once again, the reactor coolant pressure may be utilized to raise the drive rod and thus pivot the latching mechanism so that the drive rod passes above the latching mechanism. Again, the mechanism pressure can be equalized which allows the drive rod to fall and pass by the latching mechanism so that the drive rod approaches the reactor core. (author)

[Prevention of drink driving at academic festivals: «Tú decides» project].

Science.gov (United States)

Malveiro, Jorge; de Jesus, Saul Neves; Viseo, Joao; Pechorro, Pedro; Pacheco, Eusébio; Lima-Rodríguez, Joaquín Salvador; Lima-Serrano, Marta

2015-01-01

Alcohol consumption among university students has reached worrying levels, its effects on driving being highly dangerous. This aspect emphasizes the need to develop prevention programs, intended to raise subjects' awareness about the effects of alcohol on driving. The aim of the present research is to evaluate the effectiveness of the intervention program «Tú decides», implemented at the Algarve University during several students festivals, between 2010-2014. Quasi-experimental study, pre-post test without control group. A total of 5,079 participants were inquired. They were asked, at two different moments, before and after the measurement of the blood alcohol level and giving an information session with technical recommendations to prevent driving under alcohol effects. One factor ANOVA test used, in order to perform a mean comparison, as well as the Chi-square statistics, to perform a proportion comparison (p<.05). It was found that the intention to drive was lower at the second moment (42.1%) (χ(2)=2078.71; p=.000). This intention was influenced by blood alcohol level different levels (χ(2)=338.252; p=.000), gender (χ(2)=35.718; p=.000), age (χ(2)=62.805; p=.000) and professional situation of the participants (χ(2)=27.397; p=.001). We can affirm that the main objective of this intervention was achieved, since the participants followed the technical recommendations based on the blood alcohol level results. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Driving range estimation for electric vehicles based on driving condition identification and forecast

Science.gov (United States)

Pan, Chaofeng; Dai, Wei; Chen, Liao; Chen, Long; Wang, Limei

2017-10-01

With the impact of serious environmental pollution in our cities combined with the ongoing depletion of oil resources, electric vehicles are becoming highly favored as means of transport. Not only for the advantage of low noise, but for their high energy efficiency and zero pollution. The Power battery is used as the energy source of electric vehicles. However, it does currently still have a few shortcomings, noticeably the low energy density, with high costs and short cycle life results in limited mileage compared with conventional passenger vehicles. There is great difference in vehicle energy consumption rate under different environment and driving conditions. Estimation error of current driving range is relatively large due to without considering the effects of environmental temperature and driving conditions. The development of a driving range estimation method will have a great impact on the electric vehicles. A new driving range estimation model based on the combination of driving cycle identification and prediction is proposed and investigated. This model can effectively eliminate mileage errors and has good convergence with added robustness. Initially the identification of the driving cycle is based on Kernel Principal Component feature parameters and fuzzy C referring to clustering algorithm. Secondly, a fuzzy rule between the characteristic parameters and energy consumption is established under MATLAB/Simulink environment. Furthermore the Markov algorithm and BP(Back Propagation) neural network method is utilized to predict the future driving conditions to improve the accuracy of the remaining range estimation. Finally, driving range estimation method is carried out under the ECE 15 condition by using the rotary drum test bench, and the experimental results are compared with the estimation results. Results now show that the proposed driving range estimation method can not only estimate the remaining mileage, but also eliminate the fluctuation of the

Examining physiological responses across different driving maneuvers during an on-road driving task: a pilot study comparing older and younger drivers.

Science.gov (United States)

Koppel, S; Kuo, J; Berecki-Gisolf, J; Boag, R; Hue, Y-X; Charlton, J L

2015-01-01

This pilot study aimed to investigate physiological responses during an on-road driving task for older and younger drivers. Five older drivers (mean age = 74.60 years [2.97]) and 5 younger drivers (mean age = 30.00 years [3.08]) completed a series of cognitive assessments (Montreal Cognitive Assessment [MoCA], Mini Mental Status Examination [MMSE]; Trail Making Test [Trails A and Trails B]) and an on-road driving task along a predetermined, standardized urban route in their own vehicle. Driving performance was observed and scored by a single trained observer using a standardized procedure, where driving behaviors (appropriate and inappropriate) were scored for intersection negotiation, lane changing, and merging. During the on-road driving task, participants' heart rate (HR) was monitored with an unobtrusive physiological monitor. Younger drivers performed significantly better on all cognitive assessments compared to older drivers (MoCA: t(8) = 3.882, P task revealed a high level of appropriate overall driving behavior (M = 87%, SD = 7.62, range = 73-95%), including intersection negotiation (M = 89%, SD = 8.37%), lane changing (M = 100%), and merging (M = 53%, SD = 28.28%). The overall proportion of appropriate driving behavior did not significantly differ across age groups (younger drivers: M = 87.6%, SD = 9.04; older drivers: M = 87.0%, SD = 6.96; t(8) = 0.118, P =.91). Although older drivers scored lower than younger drivers on the cognitive assessments, there was no indication of cognitive overload among older drivers based on HR response to the on-road driving task. The results provide preliminary evidence that mild age-related cognitive impairment may not pose a motor vehicle crash hazard for the wider older driver population. To maintain safe mobility of the aging population, further research into the specific crash risk factors in the older driver population is warranted.

Driving: a road to unhealthy lifestyles and poor health outcomes.

Science.gov (United States)

Ding, Ding; Gebel, Klaus; Phongsavan, Philayrath; Bauman, Adrian E; Merom, Dafna

2014-01-01

Driving is a common part of modern society, but its potential effects on health are not well understood. The present cross-sectional study (n = 37,570) examined the associations of driving time with a series of health behaviors and outcomes in a large population sample of middle-aged and older adults using data from the Social, Economic, and Environmental Factor Study conducted in New South Wales, Australia, in 2010. Multiple logistic regression was used in 2013 to examine the associations of usual daily driving time with health-related behaviors (smoking, alcohol use, diet, physical activity, sedentary behavior, sleep) and outcomes (obesity, general health, quality of life, psychological distress, time stress, social functioning), adjusted for socio-demographic characteristics. Findings suggested that longer driving time was associated with higher odds for smoking, insufficient physical activity, short sleep, obesity, and worse physical and mental health. The associations consistently showed a dose-response pattern and more than 120 minutes of driving per day had the strongest and most consistent associations with the majority of outcomes. This study highlights driving as a potential lifestyle risk factor for public health. More population-level multidisciplinary research is needed to understand the mechanism of how driving affects health.

Driving: a road to unhealthy lifestyles and poor health outcomes.

Directory of Open Access Journals (Sweden)

Ding Ding

Full Text Available BACKGROUND: Driving is a common part of modern society, but its potential effects on health are not well understood. PURPOSE: The present cross-sectional study (n = 37,570 examined the associations of driving time with a series of health behaviors and outcomes in a large population sample of middle-aged and older adults using data from the Social, Economic, and Environmental Factor Study conducted in New South Wales, Australia, in 2010. METHODS: Multiple logistic regression was used in 2013 to examine the associations of usual daily driving time with health-related behaviors (smoking, alcohol use, diet, physical activity, sedentary behavior, sleep and outcomes (obesity, general health, quality of life, psychological distress, time stress, social functioning, adjusted for socio-demographic characteristics. RESULTS: Findings suggested that longer driving time was associated with higher odds for smoking, insufficient physical activity, short sleep, obesity, and worse physical and mental health. The associations consistently showed a dose-response pattern and more than 120 minutes of driving per day had the strongest and most consistent associations with the majority of outcomes. CONCLUSION: This study highlights driving as a potential lifestyle risk factor for public health. More population-level multidisciplinary research is needed to understand the mechanism of how driving affects health.

Medications and impaired driving.

Science.gov (United States)

Hetland, Amanda; Carr, David B

2014-04-01

To describe the association of specific medication classes with driving outcomes and provide clinical recommendations. The MEDLINE and EMBASE databases were searched for articles published from January 1973 to June 2013 on classes of medications associated with driving impairment. The search included outcome terms such as automobile driving, motor vehicle crash, driving simulator, and road tests. Only English-language articles that contained findings from observational or interventional designs with ≥ 10 participants were included in this review. Cross-sectional studies, case series, and case reports were excluded. Driving is an important task and activity for the majority of adults. Some commonly prescribed medications have been associated with driving impairment measured by road performance, driving simulation, and/or motor vehicle crashes. This review of 30 studies identified findings with barbiturates, benzodiazepines, hypnotics, antidepressants, opioid and nonsteroidal analgesics, anticonvulsants, antipsychotics, antiparkinsonian agents, skeletal muscle relaxants, antihistamines, anticholinergic medications, and hypoglycemic agents. Additional studies of medication impact on sedation, sleep latency, and psychomotor function, as well as the role of alcohol, are also discussed. Psychotropic agents and those with central nervous system side effects were associated with measures of impaired driving performance. It is difficult to determine if such associations are actually a result of medication use or the medical diagnosis itself. Regardless, clinicians should be aware of the increased risk of impaired driving with specific classes of medications, educate their patients, and/or consider safer alternatives.

In Patients With Cirrhosis, Driving Simulator Performance Is Associated With Real-life Driving.

Science.gov (United States)

Lauridsen, Mette M; Thacker, Leroy R; White, Melanie B; Unser, Ariel; Sterling, Richard K; Stravitz, Richard T; Matherly, Scott; Puri, Puneet; Sanyal, Arun J; Gavis, Edith A; Luketic, Velimir; Siddiqui, Muhammad S; Heuman, Douglas M; Fuchs, Michael; Bajaj, Jasmohan S

2016-05-01

Minimal hepatic encephalopathy (MHE) has been linked to higher real-life rates of automobile crashes and poor performance in driving simulation studies, but the link between driving simulator performance and real-life automobile crashes has not been clearly established. Furthermore, not all patients with MHE are unsafe drivers, but it is unclear how to distinguish them from unsafe drivers. We investigated the link between performance on driving simulators and real-life automobile accidents and traffic violations. We also aimed to identify features of unsafe drivers with cirrhosis and evaluated changes in simulated driving skills and MHE status after 1 year. We performed a study of outpatients with cirrhosis (n = 205; median 55 years old; median model for end-stage liver disease score, 9.5; none with overt hepatic encephalopathy or alcohol or illicit drug use within previous 6 months) seen at the Virginia Commonwealth University and McGuire Veterans Administration Medical Center, from November 2008 through April 2014. All participants were given paper-pencil tests to diagnose MHE (98 had MHE; 48%), and 163 patients completed a standardized driving simulation. Data were collected on traffic violations and automobile accidents from the Virginia Department of Motor Vehicles and from participants' self-assessments when they entered the study, and from 73 participants 1 year later. Participants also completed a questionnaire about alcohol use and cessation patterns. The driving simulator measured crashes, run-time, road center and edge excursions, and illegal turns during navigation; before and after each driving simulation session, patients were asked to rate their overall driving skills. Drivers were classified as safe or unsafe based on crashes and violations reported on official driving records; simulation results were compared with real-life driving records. Multivariable regression analyses of real-life crashes and violations was performed using data on

Correspondence between Simulator and On-Road Drive Performance: Implications for Assessment of Driving Safety.

Science.gov (United States)

Aksan, Nazan; Hacker, Sarah D; Sager, Lauren; Dawson, Jeffrey; Anderson, Steven; Rizzo, Matthew

2016-03-01

Forty-two younger (Mean age = 35) and 37 older drivers (Mean age = 77) completed four similar simulated drives. In addition, 32 younger and 30 older drivers completed a standard on-road drive in an instrumented vehicle. Performance in the simulated drives was evaluated using both electronic drive data and video-review of errors. Safety errors during the on-road drive were evaluated by a certified driving instructor blind to simulator performance, using state Department of Transportation criteria. We examined the degree of convergence in performance across the two platforms on various driving tasks including lane change, lane keeping, speed control, stopping, turns, and overall performance. Differences based on age group indicated a pattern of strong relative validity for simulator measures. However, relative rank-order in specific metrics of performance suggested a pattern of moderate relative validity. The findings have implications for the use of simulators in assessments of driving safety as well as its use in training and/or rehabilitation settings.

Cellular phone use while driving at night.

Science.gov (United States)

Vivoda, Jonathon M; Eby, David W; St Louis, Renée M; Kostyniuk, Lidia P

2008-03-01

Use of a cellular phone has been shown to negatively affect one's attention to the driving task, leading to an increase in crash risk. At any given daylight hour, about 6% of US drivers are actively talking on a hand-held cell phone. However, previous surveys have focused only on cell phone use during the day. Driving at night has been shown to be a riskier activity than driving during the day. The purpose of the current study was to assess the rate of hand-held cellular phone use while driving at night, using specialized night vision equipment. In 2006, two statewide direct observation survey waves of nighttime cellular phone use were conducted in Indiana utilizing specialized night vision equipment. Combined results of driver hand-held cellular phone use from both waves are presented in this manuscript. The rates of nighttime cell phone use were similar to results found in previous daytime studies. The overall rate of nighttime hand-held cellular phone use was 5.8 +/- 0.6%. Cellular phone use was highest for females and for younger drivers. In fact, the highest rate observed during the study (of 11.9%) was for 16-to 29-year-old females. The high level of cellular phone use found within the young age group, coupled with the increased crash risk associated with cellular phone use, nighttime driving, and for young drivers in general, suggests that this issue may become an important transportation-related concern.

Superluminal warp drive

Energy Technology Data Exchange (ETDEWEB)

Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)], E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es

2007-09-20

In this Letter we consider a warp drive spacetime resulting from that suggested by Alcubierre when the spaceship can only travel faster than light. Restricting to the two dimensions that retains most of the physics, we derive the thermodynamic properties of the warp drive and show that the temperature of the spaceship rises up as its apparent velocity increases. We also find that the warp drive spacetime can be exhibited in a manifestly cosmological form.

Older drivers' self-assessed driving skills, driving-related stress and self-regulation in traffic

DEFF Research Database (Denmark)

Siren, Anu Kristiina; Meng, Annette

2013-01-01

Previous research on older drivers has indicated connections between self-rated driving ability, confidence in their own driving, driving-related stress, and self-regulatory behaviour. However, more systematic associations between older drivers' perceptions on their own driving and self......-regulation or driver stress and self-regulation behaviour, and possible gender differences in these, have not been obtained in previous studies. The aim of the present study was to gain a better understanding of older drivers' self-regulatory driving and the motivators behind this behaviour, by placing this behaviour...... and avoidance than situations related to infrastructure, and women were more likely to report discomfort and avoidance of driving situations. The results suggest that older drivers generally show good self-judgement of changes in their driving skills and acknowledge the different types of skills comprised...

Power-Quality-Oriented Optimization in Multiple Three-Phase Adjustable Speed Drives

DEFF Research Database (Denmark)

Yang, Yongheng; Davari, Pooya; Blaabjerg, Frede

2016-01-01

As an almost standardized configuration, Diode Rectifiers (DRs) and Silicon-Controlled Rectifiers (SCRs) are commonly employed as the front-end topology in three-phase Adjustable Speed Drive (ASD) systems. Features of this ASD configuration include: structural and control simplicity, small volume......, low cost, and high reliability during operation. Yet, DRs and SCRs bring harmonic distortions in the mains and thus lowering the overall efficiency. Power quality standards/rules are thus released. For multiple ASD systems, certain harmonics of the total grid current can be mitigated by phase......-shifting the currents drawn by SCR-fed drives, and thus it is much flexible to reduce the Total Harmonic Distortion (THD) level in such applications. However, the effectiveness of this harmonic mitigation scheme for multiple ASD systems depends on: a) the number of parallel drives, b) the power levels, and c...

Exploring the association between working memory and driving performance in Parkinson's disease.

Science.gov (United States)

Vardaki, Sophia; Devos, Hannes; Beratis, Ion; Yannis, George; Papageorgiou, Sokratis G

2016-05-18

The aim of this study was to explore whether varying levels of operational and tactical driving task demand differentially affect drivers with Parkinson's disease (PD) and control drivers in their sign recall. Study participants aged between 50 and 70 years included a group of drivers with PD (n = 10) and a group of age- and sex-matched control drivers (n = 10). Their performance in a sign recall task was measured using a driving simulator. Drivers in the control group performed better than drivers with PD in a sign recall task, but this trend was not statistically significant (P =.43). In addition, regardless of group membership, subjects' performance differed according to varying levels of task demand. Performance in the sign recall task was more likely to drop with increasing task demand (P =.03). This difference was significant when the variation in task demand was associated with a cognitive task; that is, when drivers were required to apply the instructions from working memory. Although the conclusions drawn from this study are tentative, the evidence presented here is encouraging with regard to the use of a driving simulator to examine isolated cognitive functions underlying driving performance in PD. With an understanding of its limitations, such driving simulation in combination with functional assessment batteries measuring physical, visual, and cognitive abilities could comprise one component of a multitiered system to evaluate medical fitness to drive.

Effects of decades of physical driving on body movement and motion sickness during virtual driving.

Directory of Open Access Journals (Sweden)

Thomas A Stoffregen

Full Text Available We investigated relations between experience driving physical automobiles and motion sickness during the driving of virtual automobiles. Middle-aged individuals drove a virtual automobile in a driving video game. Drivers were individuals who had possessed a driver's license for approximately 30 years, and who drove regularly, while non-drivers were individuals who had never held a driver's license, or who had not driven for more than 15 years. During virtual driving, we monitored movement of the head and torso. During virtual driving, drivers became motion sick more rapidly than non-drivers, but the incidence and severity of motion sickness did not differ as a function of driving experience. Patterns of movement during virtual driving differed as a function of driving experience. Separately, movement differed between participants who later became motion sick and those who did not. Most importantly, physical driving experience influenced patterns of postural activity that preceded motion sickness during virtual driving. The results are consistent with the postural instability theory of motion sickness, and help to illuminate relations between the control of physical and virtual vehicles.

Parametric tests of a traction drive retrofitted to an automotive gas turbine

Science.gov (United States)

Rohn, D. A.; Lowenthal, S. H.; Anderson, N. E.

1980-01-01

The results of a test program to retrofit a high performance fixed ratio Nasvytis Multiroller Traction Drive in place of a helical gear set to a gas turbine engine are presented. Parametric tests up to a maximum engine power turbine speed of 45,500 rpm and to a power level of 11 kW were conducted. Comparisons were made to similar drives that were parametrically tested on a back-to-back test stand. The drive showed good compatibility with the gas turbine engine. Specific fuel consumption of the engine with the traction drive speed reducer installed was comparable to the original helical gearset equipped engine.

Driving competences and neuropsychological factors associated to driving counseling in multiple sclerosis.

Science.gov (United States)

Badenes, Dolors; Garolera, Maite; Casas, Laura; Cejudo-Bolivar, Juan Carlos; de Francisco, Jorge; Zaragoza, Silvia; Calzado, Noemi; Aguilar, Miquel

2014-05-01

Multiple Sclerosis (MS) significantly impacts daily living activities, including car driving. To investigate driving difficulties experienced with MS, we compared 50 MS patients with minor or moderate disability and 50 healthy controls (HC) using computerized driving tests (the ASDE driver test and the Useful Field of View (UFOV) test) and neuropsychological tests. Inclusion criteria included being active drivers. We evaluated whether cognitive deterioration in MS is associated with the results of driving tests by comparing MS patients without cognitive deterioration with HC. The results indicated that the MS patients performed worse than the HCs in attention, information processing, working memory and visuomotor coordination tasks. Furthermore, MS patients with cognitive impairments experienced more difficulties in the driving tests than did the non-impaired MS patients. Motor dysfunction associated with MS also played an important role in this activity. The results of this study suggest that MS should be assessed carefully and that special emphasis should be placed on visuomotor coordination and executive functions because patients with minor motor disability and subtle cognitive impairments can pass measures predictive of driving safety.

Impact of distracted driving on safety and traffic flow.

Science.gov (United States)

Stavrinos, Despina; Jones, Jennifer L; Garner, Annie A; Griffin, Russell; Franklin, Crystal A; Ball, David; Welburn, Sharon C; Ball, Karlene K; Sisiopiku, Virginia P; Fine, Philip R

2013-12-01

Studies have documented a link between distracted driving and diminished safety; however, an association between distracted driving and traffic congestion has not been investigated in depth. The present study examined the behavior of teens and young adults operating a driving simulator while engaged in various distractions (i.e., cell phone, texting, and undistracted) and driving conditions (i.e., free flow, stable flow, and oversaturation). Seventy five participants 16-25 years of age (split into 2 groups: novice drivers and young adults) drove a STISIM simulator three times, each time with one of three randomly presented distractions. Each drive was designed to represent daytime scenery on a 4 lane divided roadway and included three equal roadway portions representing Levels of Service (LOS) A, C, and E as defined in the 2000 Highway Capacity Manual. Participants also completed questionnaires documenting demographics and driving history. Both safety and traffic flow related driving outcomes were considered. A Repeated Measures Multivariate Analysis of Variance was employed to analyze continuous outcome variables and a Generalized Estimate Equation (GEE) Poisson model was used to analyze count variables. Results revealed that, in general more lane deviations and crashes occurred during texting. Distraction (in most cases, text messaging) had a significantly negative impact on traffic flow, such that participants exhibited greater fluctuation in speed, changed lanes significantly fewer times, and took longer to complete the scenario. In turn, more simulated vehicles passed the participant drivers while they were texting or talking on a cell phone than while undistracted. The results indicate that distracted driving, particularly texting, may lead to reduced safety and traffic flow, thus having a negative impact on traffic operations. No significant differences were detected between age groups, suggesting that all drivers, regardless of age, may drive in a manner

Parental perceptions of teen driving: Restrictions, worry and influence.

Science.gov (United States)

Jewett, Amy; Shults, Ruth A; Bhat, Geeta

2016-12-01

Parents play a critical role in preventing crashes among teens. Research of parental perceptions and concerns regarding teen driving safety is limited. We examined results from the 2013 Summer ConsumerStyles survey that queried parents about restrictions placed on their teen drivers, their perceived level of "worry" about their teen driver's safety, and influence of parental restrictions regarding their teen's driving. We produced frequency distributions for the number of restrictions imposed, parental "worry," and influence of rules regarding their teen's driving, reported by teen's driving license status (learning to drive or obtained a driver's license). Response categories were dichotomized because of small cell sizes, and we ran separate log-linear regression models to explore whether imposing all four restrictions on teen drivers was associated with either worry intensity ("a lot" versus "somewhat, not very much or not at all") or perceived influence of parental rules ("a lot" versus "somewhat, not very much or not at all"). Among the 456 parent respondents, 80% reported having restrictions for their teen driver regarding use of safety belts, drinking and driving, cell phones, and text messaging while driving. However, among the 188 parents of licensed teens, only 9% reported having a written parent-teen driving agreement, either currently or in the past. Worrying "a lot" was reported less frequently by parents of newly licensed teens (36%) compared with parents of learning teens (61%). Parents report having rules and restrictions for their teen drivers, but only a small percentage formalize the rules and restrictions in a written parent-teen driving agreement. Parents worry less about their teen driver's safety during the newly licensed phase, when crash risk is high as compared to the learning phase. Further research is needed into how to effectively support parents in supervising and monitoring their teen driver. Published by Elsevier Ltd.

Perception of the Risks Associated with Impaired Driving and Effects on Driving Behavior

OpenAIRE

Georges Dionne; Claude Fluet; Denise Desjardins

2006-01-01

This research studies the perception of the risks associated with impaired driving-probability of being apprehended or of having an accident-and the relation between the perception of risks and driving behavior. The most important determinants of perceptual biases are age, an accumulation of violations in the year preceding the survey, being a non-drinker, knowledge of the legal alcohol limit for driving, opinion about zero tolerance for impaired driving, and family income. Perceptual biases ...

Epilepsy and driving

Directory of Open Access Journals (Sweden)

Matej Mavrič

2015-05-01

Full Text Available Epilepsy poses a risk for all participants in road traffic; therefore people with epilepsy do not meet the criteria for an unlimited driving license. Their driving is affected not only by epileptic seizures causing impaired consciousness and involuntary movements, but also by antiepileptic drugs with their many unwanted affects. The experts have not yet agreed on whether people with epilepsy have an increased risk of experiencing a road traffic accident. However, recent data suggests that the overall risk is lower compared to other medical conditions. Scientific evidence forms the basis of legislation, which by limiting people with epilepsy, enables all participants in road traffic to drive in the safest possible environment. The legislation that governs epilepsy and driving in Slovenia has been recently thoroughly reformed and thus allows a less discriminatory management of people with epilepsy. Although people with epilepsy experience many issues in their daily life, including their personal relationships and employment, they often list the need for driving as a top concern in surveys. General physicians play an important role in managing the issues of people with epilepsy.

Control rod drives

International Nuclear Information System (INIS)

Hayakawa, Hiroyasu.

1979-01-01

Purpose: To enable rapid control in a simple circuit by providing a motor control device having an electric capacity capable of simultaneously driving all of the control rods rapidly only in the inserting direction as well as a motor controlling device capable of fine control for the insertion and extraction at usual operation. Constitution: The control rod drives comprise a first motor control device capable of finely controlling the control rods both in inserting and extracting directions, a second motor control device capable of rapidly driving the control rods only in the inserting direction, and a first motor switching circuit and a second motor switching circuit switched by switches. Upon issue of a rapid insertion instruction for the control rods, the second motor switching circuit is closed by the switch and the second motor control circuit and driving motors are connected. Thus, each of the control rod driving motors is driven at a high speed in the inserting direction to rapidly insert all of the control rods. (Yoshino, Y.)

A Virtual Environments Editor for Driving Scenes

Directory of Open Access Journals (Sweden)

Ronald R. Mourant

2003-12-01

Full Text Available The goal of this project was to enable the rapid creation of three-dimensional virtual driving environments. We designed and implemented a high-level scene editor that allows a user to construct a driving environment by pasting icons that represent 1 road segments, 2 road signs, 3 trees and 4 buildings. These icons represent two- and three-dimensional objects that have been predesigned. Icons can be placed in the scene at specific locations (x, y, and z coordinates. The editor includes the capability of a user to "drive" a vehicle using a computer mouse for steering, accelerating and braking. At any time during the process of building a virtual environment, a user may switch to "Run Mode" and inspect the three-dimensional scene by "driving" through it using the mouse. Adjustments and additions can be made to the virtual environment by going back to "Build Mode". Once a user is satisfied with the threedimensional virtual environment, it can be saved in a file. The file can used with Java3D software that enables the traversing of three-dimensional environments. The process of building virtual environments from predesigned icons can be applied to many other application areas. It will enable novice computer users to rapidly construct and use three-dimensional virtual environments.

Perceptions, intentions and behavioral norms that affect pre-license driving among Arab youth in Israel.

Science.gov (United States)

Gesser-Edelsburg, Anat; Zemach, Mina; Lotan, Tsippy; Elias, Wafa; Grimberg, Einat

2018-02-01

The present study examines reported pre-license driving among youth from the population of Arab citizens of Israel. The purpose of the present study is to examine which sociodemographic variables, attitudes and perceptions about safe driving and individual and societal behavioral norms are associated with pre-license driving. The research distinguished between the factors that actually contribute to pre-license driving (reported behavior, peer norms, gender and parents' messages) and the factors that explain the intention (parental authority, social norms, parents' messages and fear of road crashes). Even though there was a significant partial overlap (84%) between those who intend to drive without a license and those who reported driving without a license, the main factors that distinguish pre-license driving groups are different from the factors that distinguish the intention to drive before receiving a license. What is unique about the findings is the identification of the context in which social norms are influential and that in which parental authority is influential. The study indicated that in the case of pre-license driving, the main motivating factor is subjective norms, whereas in the case of expecting to drive without a license, the main motivating factor is the interaction between parental authority and the messages that parents convey. While actual behavior pertains to the behavioral level, we argue that intended behavior pertains to the cognitive level. At this level, rational considerations arise, such as fear of parental punishment and fear of accidents. These considerations compete with the influence of friends and their norms, and may outweigh them. The findings suggest that it is important to safeguard youth against the influence of peer pressure as early as the stage of behavioral intentions. Follow-up studies can simulate situations of pre-license driving due to social pressure and identify the factors that might affect young people's decision

Use of Software Programs as Zero Fill Help in Overcoming the Problem Around Hard Drive

OpenAIRE

Eko Prasetyo Nugroho; Fivtatianti Fivtatianti, Skom, MM

2003-01-01

Zero Fill, is a software tool programs that are designed for hard disk drive specially branded Quantum. This software is a tool programs that function to format the hard drive. Where is the type of format here is the first format or in other words the software to format the hard drive is working under conditions of low- level or commonly referred to as a low- level format. The advantages of this software is able to fix and remove all existing data within the disk, such as files...

Isolation and functional characterization of a cotton ubiquitination-related promoter and 5'UTR that drives high levels of expression in root and flower tissues.

Science.gov (United States)

Viana, Antonio A B; Fragoso, Rodrigo R; Guimarães, Luciane M; Pontes, Naiara; Oliveira-Neto, Osmundo B; Artico, Sinara; Nardeli, Sarah M; Alves-Ferreira, Marcio; Batista, João A N; Silva, Maria C M; Grossi-de-Sa, Maria F

2011-11-24

Cotton (Gossypium spp.) is an important crop worldwide that provides raw material to 40% of the textile fiber industry. Important traits have been studied aiming the development of genetically modified crops including resistance to insect and diseases, and tolerance to drought, cold and herbicide. Therefore, the characterization of promoters and regulatory regions is also important to achieve high gene expression and/or a specific expression pattern. Commonly, genes involved in ubiquitination pathways are highly and differentially expressed. In this study, we analyzed the expression of a cotton ubiquitin-conjugating enzyme (E2) family member with no previous characterization. Nucleotide analysis revealed high identity with cotton E2 homologues. Multiple alignment showed a premature stop codon, which prevents the encoding of the conserved cysteine residue at the E2 active site, and an intron that is spliced in E2 homologues, but not in GhGDRP85. The GhGDRP85 gene is highly expressed in different organs of cotton plants, and has high transcript levels in roots. Its promoter (uceApro2) and the 5'UTR compose a regulatory region named uceA1.7, and were isolated from cotton and studied in Arabidopsis thaliana. uceA1.7 shows strong expression levels, equaling or surpassing the expression levels of CaMV35S. The uceA1.7 regulatory sequence drives GUS expression 7-fold higher in flowers, 2-fold in roots and at similar levels in leaves and stems. GUS expression levels are decreased 7- to 15-fold when its 5'UTR is absent in uceApro2. uceA1.7 is a strong constitutive regulatory sequence composed of a promoter (uceApro2) and its 5'UTR that will be useful in genetic transformation of dicots, having high potential to drive high levels of transgene expression in crops, particularly for traits desirable in flower and root tissues.

Control rod drive

International Nuclear Information System (INIS)

Hawke, B.C.

1986-01-01

A reactor core, one or more control rods, and a control rod drive are described for selectively inserting and withdrawing the one or more control rods into and from the reactor core, which consists of: a support structure secured beneath the reactor core; control rod positioning means supported by the support structure for movably supporting the control rod for movement between a lower position wherein the control rod is located substantially beneath the reactor core and an upper position wherein at least an upper portion of the control rod extends into the reactor core; transmission means; primary drive means connected with the control rod positioning means by the transmission means for positioning the control rod under normal operating conditions; emergency drive means for moving the control rod from the lower position to the upper position under emergency conditions, the emergency drive means including a weight movable between an upper and a lower position, means for movably supporting the weight, and means for transmitting gravitational force exerted on the weight to the control rod positioning means to move the control rod upwardly when the weight is pulled downwardly by gravity; the transmission means connecting the control rod positioning means with the emergency drive means so that the primary drive means effects movement of the weight and the control rod in opposite directions under normal conditions, thus providing counterbalancing to reduce the force required for upward movement of the control rod under normal conditions; and restraint means for restraining the fall of the weight under normal operating conditions and disengaging the primary drive means to release the weight under emergency conditions

Noninductive current drive in tokamaks

International Nuclear Information System (INIS)

Uckan, N.A.

1985-01-01

Various current drive mechanisms may be grouped into four classes: (1) injection of energetic particle beams; (2) launching of rf waves; (3) hybrid schemes, which are combinations of various rf schemes (rf plus beams, rf and/or beam plus ohmic heating, etc.); and (4) other schemes, some of which are specific to reactor plasma conditions requiring the presence of alpha particle or intense synchrotron radiation. Particle injection schemes include current drive by neutral beams and relativistic electron beams. The rf schemes include current drive by the lower hybrid (LH) waves, the electron waves, the waves in the ion cyclotron range of frequencies, etc. Only a few of these approaches, however, have been tested experimentally, with the broadest data base available for LH waves. Included in this report are (1) efficiency criteria for current drive, (2) current drive by neutral beam injection, (3) LH current drive, (4) electron cyclotron current drive, (5) current drive by ion cyclotron waves - minority species heating, and (6) current drive by other schemes (such as hybrids and low frequency waves)

Hospital outpatients' responses to taking medications with driving warnings.

Science.gov (United States)

Smyth, T; Sheehan, M; Siskind, V

2013-01-01

The study investigates the knowledge, intentions, and driving behavior of persons prescribed medications that display a warning about driving. It also examines their confidence that they can self-assess possible impairment, as is required by the Australian labeling system. We surveyed 358 outpatients in an Australian public hospital pharmacy, representing a well-advised group taking a range of medications including those displaying a warning label about driving. A brief telephone follow-up survey was conducted with a subgroup of the participants. The sample had a median age of 53.2 years and was 53 percent male. Nearly three quarters (73.2%) had taken a potentially impairing class of medication and more than half (56.1%) had taken more than one such medication in the past 12 months. Knowledge of the potentially impairing effects of medication was relatively high for most items; however, participants underestimated the possibility of increased impairment from exceeding the prescribed dose and at commencing treatment. Participants' responses to the safety implications of taking drugs with the highest level of warning varied. Around two thirds (62.8%) indicated that they would consult a health practitioner for advice and around half would modify their driving in some way. However, one fifth (20.9%) would drive when the traffic was thought to be less heavy and over a third (37.7%) would modify their medication regime so that they could drive. The findings from the follow-up survey of a subsample taking target drugs at the time of the first interview were also of concern. Only just over half (51%) recalled seeing the warning label on their medications and, of this group, three quarters (78%) reported following the warning label advice. These findings indicated that there remains a large proportion of people who either did not notice or did not consider the warning when deciding whether to drive. There was a very high level of confidence in this group that they could

Teen Driving Risk and Prevention: Naturalistic Driving Research Contributions and Challenges

OpenAIRE

Simons-Morton, Bruce G.; Ehsani, Johnathon P.; Gershon, Pnina; Klauer, Sheila G.; Dingus, Thomas A.

2017-01-01

Naturalistic driving (ND) methods may be particularly useful for research on young driver crash risk. Novices are not safe drivers initially, but tend to improve rapidly, although the pace of learning is highly variable. However, knowledge is lacking about how best to reduce the learning curve and the variability in the development of safe driving judgment. A great deal has been learned from recent naturalistic driving (ND) studies that have included young drivers, providing objective informa...

Research on Evaluation Model for Secondary Task Driving Safety Based on Driver Eye Movements

Directory of Open Access Journals (Sweden)

Lisheng Jin

2014-01-01

Full Text Available This study was designed to gain insight into the influence of performing different types of secondary task while driving on driver eye movements and to build a safety evaluation model for secondary task driving. Eighteen young drivers were selected and completed the driving experiment on a driving simulator. Measures of fixations, saccades, and blinks were analyzed. Based on measures which had significant difference between the baseline and secondary tasks driving conditions, the evaluation index system was built. Method of principal component analysis (PCA was applied to analyze evaluation indexes data in order to obtain the coefficient weights of indexes and build the safety evaluation model. Based on evaluation scores, the driving safety was grouped into five levels (very high, high, average, low, and very low using K-means clustering algorithm. Results showed that secondary task driving severely distracts the driver and the evaluation model built in this study could estimate driving safety effectively under different driving conditions.

Modeling Driving Performance Using In-Vehicle Speech Data From a Naturalistic Driving Study.

Science.gov (United States)

Kuo, Jonny; Charlton, Judith L; Koppel, Sjaan; Rudin-Brown, Christina M; Cross, Suzanne

2016-09-01

We aimed to (a) describe the development and application of an automated approach for processing in-vehicle speech data from a naturalistic driving study (NDS), (b) examine the influence of child passenger presence on driving performance, and (c) model this relationship using in-vehicle speech data. Parent drivers frequently engage in child-related secondary behaviors, but the impact on driving performance is unknown. Applying automated speech-processing techniques to NDS audio data would facilitate the analysis of in-vehicle driver-child interactions and their influence on driving performance. Speech activity detection and speaker diarization algorithms were applied to audio data from a Melbourne-based NDS involving 42 families. Multilevel models were developed to evaluate the effect of speech activity and the presence of child passengers on driving performance. Speech activity was significantly associated with velocity and steering angle variability. Child passenger presence alone was not associated with changes in driving performance. However, speech activity in the presence of two child passengers was associated with the most variability in driving performance. The effects of in-vehicle speech on driving performance in the presence of child passengers appear to be heterogeneous, and multiple factors may need to be considered in evaluating their impact. This goal can potentially be achieved within large-scale NDS through the automated processing of observational data, including speech. Speech-processing algorithms enable new perspectives on driving performance to be gained from existing NDS data, and variables that were once labor-intensive to process can be readily utilized in future research. © 2016, Human Factors and Ergonomics Society.

Dementia and driving

Science.gov (United States)

... this page: //medlineplus.gov/ency/patientinstructions/000028.htm Dementia and driving To use the sharing features on ... please enable JavaScript. If your loved one has dementia , deciding when they can no longer drive may ...

Driving After a Stroke

Science.gov (United States)

... 23,2015 Can I drive after a stroke? Driving is often a major concern after someone has a stroke. It’s not unusual for stroke survivors to want to drive. Being able to get around after a stroke is important. Safety behind the wheel is even more important after ...

A linear chromatic mechanism drives the pupillary response.

Science.gov (United States)

Tsujimura, S.; Wolffsohn, J. S.; Gilmartin, B.

2001-01-01

Previous studies have shown that a chromatic mechanism can drive pupil responses. The aim of this research was to clarify whether a linear or nonlinear chromatic mechanism drives pupillary responses by using test stimuli of various colours that are defined in cone contrast space. The pupil and accommodation responses evoked by these test stimuli were continuously and simultaneously objectively measured by photorefraction. The results with isochromatic and isoluminant stimuli showed that the accommodative level remained approximately constant (< 0.25 D change in mean level) even when the concurrent pupillary response was large (ca. 0.30 mm). The pupillary response to an isoluminant grating was sustained, delayed (by ca. 60 ms) and larger in amplitude than that for a isochromatic uniform stimulus, which supports previous work suggesting that the chromatic mechanism contributes to the pupillary response. In a second experiment, selected chromatic test gratings were used and isoresponse contours in cone contrast space were obtained. The results showed that the isoresponse contour in cone contrast space is well described (r(2) = 0.99) by a straight line with a positive slope. The results indicate that a /L - M/ linear chromatic mechanism, whereby a signal from the long wavelength cone is subtracted from that of the middle wavelength cone and vice versa, drives pupillary responses. PMID:11674867

Mitigating Drive-By Download Attacks: Challenges and Open Problems

Science.gov (United States)

Egele, Manuel; Kirda, Engin; Kruegel, Christopher

Malicious web sites perform drive-by download attacks to infect their visitors with malware. Current protection approaches rely on black- or white-listing techniques that are difficult to keep up-to-date. As todays drive-by attacks already employ encryption to evade network level detection we propose a series of techniques that can be implemented in web browsers to protect the user from such threats. In addition, we discuss challenges and open problems that these mechanisms face in order to be effective and efficient.

From genes to games: cooperation and cyclic dominance in meiotic drive.

Science.gov (United States)

Traulsen, Arne; Reed, Floyd A

2012-04-21

Evolutionary change can be described on a genotypic level or a phenotypic level. Evolutionary game theory is typically thought of as a phenotypic approach, although it is frequently argued that it can also be used to describe population genetic evolution. Interpreting the interaction between alleles in a diploid genome as a two player game leads to interesting alternative perspectives on genetic evolution. Here we focus on the case of meiotic drive and illustrate how meiotic drive can be directly and precisely interpreted as a social dilemma, such as the prisoners dilemma or the snowdrift game, in which the drive allele takes more than its fair share. Resistance to meiotic drive can lead to the well understood cyclic dominance found in the rock-paper-scissors game. This perspective is well established for the replicator dynamics, but there is still considerable ground for mutual inspiration between the two fields. For example, evolutionary game theorists can benefit from considering the stochastic evolutionary dynamics arising from finite population size. Population geneticists can benefit from game theoretic tools and perspectives on genetic evolution. Copyright © 2011 Elsevier Ltd. All rights reserved.

THE IMPACT OF TEXT DRIVING ON DRIVING SAFETY

OpenAIRE

Sanaz Motamedi; Jyh-Hone Wang

2016-01-01

In an increasingly mobile era, the wide availability of technology for texting and the prevalence of hands-free form have introduced a new safety concern for drivers. To assess this concern, a questionnaire was first deployed online to gain an understanding of drivers’ text driving experiences as well as their demographic information. The results from 232 people revealed that the majority of drivers are aware of the associated risks with texting while driving. However, more than one-fourth of...

i3Drive, a 3D interactive driving simulator.

Science.gov (United States)

Ambroz, Miha; Prebil, Ivan

2010-01-01

i3Drive, a wheeled-vehicle simulator, can accurately simulate vehicles of various configurations with up to eight wheels in real time on a desktop PC. It presents the vehicle dynamics as an interactive animation in a virtual 3D environment. The application is fully GUI-controlled, giving users an easy overview of the simulation parameters and letting them adjust those parameters interactively. It models all relevant vehicle systems, including the mechanical models of the suspension, power train, and braking and steering systems. The simulation results generally correspond well with actual measurements, making the system useful for studying vehicle performance in various driving scenarios. i3Drive is thus a worthy complement to other, more complex tools for vehicle-dynamics simulation and analysis.

The reality of teenage driving: the results of a driving educational experience for teens in the juvenile court system.

Science.gov (United States)

Manno, Mariann; Maranda, Louise; Rook, Allison; Hirschfeld, Ryan; Hirsh, Michael

2012-10-01

In the United States, one third of all deaths in teens are a result of motor vehicle crashes, accounting for 6,000 deaths annually. Injury Free Coalition for Kids-Worcester in collaboration with Worcester Juvenile Court has developed an interactive program for first-time teenaged driving offenders, Reality Intensive Driver Education (Teen RIDE). This full-day program at the trauma center provides a realistic exposure to the consequences of risky driving behaviors. This article examined the driving offense recidivism rates for Teen RIDE participants versus a comparison group (CG). The intervention group (IG) consists of teenagers between 13 years and 17 years who have been arrested for the first time for a serious driving offense and are sentenced by a Worcester Juvenile Court Judge or Magistrate to the Teen RIDE program. They are required to attend the program as a condition of probation, so attendance is mandatory. Each participant in the IG completed the program and was tracked for driving reoffenses for 6 months after completion of the course. The CG consists of also first-time driving offenders. The CG was matched with the IG with respect to age (13-17 years), sex, and offense type. Springfield, Massachusetts, serves as the site for recruitment of the CG, since it is demographically similar to Worcester but 60 mi away. Students in the CG had no exposure to this program. Each CG member was also tracked for 6 months after arrest. The recidivism rate for Teen RIDE participants 6 months after the course is 6% with 0% reoffending more than once. The CG has a recidivism rate of 56% 6 months after the arrest and 14% have more than one reoffense. The CG is 13.062 (4.296-39.713) times more likely to reoffend, and this is significant (p Teen RIDE program provides an impactful exposure of the consequences of risky driving behaviors to teenaged participants. In addition, Teen RIDE participants are significantly less likely to reoffend after completion of the course

Estimation of the Driving Style Based on the Users’ Activity and Environment Influence

Science.gov (United States)

Sysoev, Mikhail; Kos, Andrej; Guna, Jože; Pogačnik, Matevž

2017-01-01

New models and methods have been designed to predict the influence of the user’s environment and activity information to the driving style in standard automotive environments. For these purposes, an experiment was conducted providing two types of analysis: (i) the evaluation of a self-assessment of the driving style; (ii) the prediction of aggressive driving style based on drivers’ activity and environment parameters. Sixty seven h of driving data from 10 drivers were collected for analysis in this study. The new parameters used in the experiment are the car door opening and closing manner, which were applied to improve the prediction accuracy. An Android application called Sensoric was developed to collect low-level smartphone data about the users’ activity. The driving style was predicted from the user’s environment and activity data collected before driving. The prediction was tested against the actual driving style, calculated from objective driving data. The prediction has shown encouraging results, with precision values ranging from 0.727 up to 0.909 for aggressive driving recognition rate. The obtained results lend support to the hypothesis that user’s environment and activity data could be used for the prediction of the aggressive driving style in advance, before the driving starts. PMID:29065476

Estimation of the Driving Style Based on the Users' Activity and Environment Influence.

Science.gov (United States)

Sysoev, Mikhail; Kos, Andrej; Guna, Jože; Pogačnik, Matevž

2017-10-21

New models and methods have been designed to predict the influence of the user's environment and activity information to the driving style in standard automotive environments. For these purposes, an experiment was conducted providing two types of analysis: (i) the evaluation of a self-assessment of the driving style; (ii) the prediction of aggressive driving style based on drivers' activity and environment parameters. Sixty seven h of driving data from 10 drivers were collected for analysis in this study. The new parameters used in the experiment are the car door opening and closing manner, which were applied to improve the prediction accuracy. An Android application called Sensoric was developed to collect low-level smartphone data about the users' activity. The driving style was predicted from the user's environment and activity data collected before driving. The prediction was tested against the actual driving style, calculated from objective driving data. The prediction has shown encouraging results, with precision values ranging from 0.727 up to 0.909 for aggressive driving recognition rate. The obtained results lend support to the hypothesis that user's environment and activity data could be used for the prediction of the aggressive driving style in advance, before the driving starts.

Acute effects of alcohol on inhibitory control and simulated driving in DUI offenders.

Science.gov (United States)

Van Dyke, Nicholas; Fillmore, Mark T

2014-06-01

The public health costs associated with alcohol-related traffic accidents have prompted considerable research aimed at identifying characteristics of individuals who drive under the influence (DUI) in order to improve treatment and prevention strategies. Survey studies consistently show that DUI offenders self-report higher levels of impulsivity compared to their nonoffending counterparts. However, little is known about how individuals with a DUI history respond under alcohol. Inhibitory control is a behavioral component of impulsivity thought to underlie risky drinking and driving behaviors. The present study examined the degree to which DUI drivers display deficits of inhibitory control in response to alcohol and the degree to which alcohol impaired their simulated driving performance. It was hypothesized that DUI offenders would display an increased sensitivity to the acute impairing effects of alcohol on simulated driving performance. Young adult drivers with a history of DUI and a demographically-comparable group of drivers with no history of DUI (controls) were tested following a 0.65 g/kg dose of alcohol and a placebo. Inhibitory control was measured by using a cued go/no-go task. Drivers then completed a driving simulation task that yielded multiple indicators of driving performance, such as within-lane deviation, steering rate, centerline crossings and road edge excursions, and drive speed. Results showed that although DUI offenders self-reported greater levels of impulsivity than did controls, no group differences were observed in the degree to which alcohol impaired inhibitory control and driving performance. The findings point to the need to identify other aspects of behavioral dysfunction underlying the self-reported impulsivity among DUI offenders, and to better understand the specific driving situations that might pose greater risk to DUI offenders. The systematic study of candidate cognitive deficits in DUI offenders will provide important

Impact of alcohol checks and social norm on driving under the influence of alcohol (DUI).

Science.gov (United States)

Meesmann, Uta; Martensen, Heike; Dupont, Emmanuelle

2015-07-01

This study investigated the influence of alcohol checks and social norm on self-reported driving under the influence of alcohol above the legal limit (DUI). The analysis was based on the responses of 12,507 car drivers from 19 European countries to the SARTRE-4 survey (2010). The data were analysed by means of a multiple logistic regression-model on two levels: (1) individual and (2) national level. On the individual level the results revealed that driving under the influence (DUI) was positively associated with male gender, young age (17-34), personal experience with alcohol checks, the perceived likelihood of being checked for alcohol, perceived drunk driving behaviour of friends (social norm) and was negatively associated with higher age (55+). On a national level, the results showed a negative association with a lower legal alcohol limit (BAC 0.2g/l compared with BAC 0.5g/l) and the percentage of drivers checked for alcohol. DUI was positively associated with the percentage of respondents in the country that reported that their friends drink and drive (social norm). The comparison of the results obtained on national and individual levels shows a paradoxical effect of alcohol checks: Countries with more alcohol checks show lower DUI (negative association) but respondents who have been personally checked for alcohol show a higher chance of DUI (positive association). Possible explanations of this paradox are discussed. The effects of the social norm variable (perceived drunk driving behaviour of friends) are positively associated with DUI on both levels. Copyright © 2015 Elsevier Ltd. All rights reserved.

Segmented motor drive - with multi-phase induction motor

DEFF Research Database (Denmark)

Bendixen, Flemming Buus

of the induction motor is set up. The model is able to calculate dynamical electric, magnetic and mechanic state variables, but initially it is used to calculate static characteristics in motors with different number of phases and different voltage supply shapes. This analysis show i.e. that the efficiency....... The multi-phase motor is selected for further analysis. The project is limited to examine if increasing the number of phases can improve the characteristics for induction motor drives. In the literature it is demonstrated that torque production in a six-phase motor can be increased, if a 3rd harmonic......This PhD project commences in modulation of motor drives, i.e. having the advantage of reducing the number of variants and improves the system reliability at error situations. Four different motor drive topologies with modular construction as common denominator are compared on a general level...

A drive through Web 2.0: an exploration of driving safety promotion on Facebook™.

Science.gov (United States)

Apatu, Emma J I; Alperin, Melissa; Miner, Kathleen R; Wiljer, David

2013-01-01

This study explored Facebook™ to capture the prevalence of driving safety promotion user groups, obtain user demographic information, to understand if Facebook™ user groups influence reported driving behaviors, and to gather a sense of perceived effectiveness of Facebook™ for driving safety promotion targeted to young adults. In total, 96 driving safety Facebook™ groups (DSFGs) were identified with a total of 33,368 members, 168 administrators, 156 officers, 1,598 wall posts representing 12 countries. A total of 85 individuals participated in the survey. Demographic findings of this study suggest that driving safety promotion can be targeted to young and older adults. Respondents' ages ranged from 18 to 66 years. A total of 62% of respondents aged ≤ 24 years and 57.8% of respondents aged ≥ 25 years reported changing their driving-related behaviors as a result of reading information on the DSFGs to which they belonged. A higher proportion of respondents ≥ 25 years were significantly more likely to report Facebook™ and YouTube™ as an effective technology for driving safety promotion. This preliminary study indicates that DSFGs may be effective tools for driving safety promotion among young adults. More research is needed to understand the cognition of Facebook™ users as it relates to adopting safe driving behavior. The findings from this study present descriptive data to guide public health practitioners for future health promotion activities on Facebook™.

Self-driving carsickness.

Science.gov (United States)

Diels, Cyriel; Bos, Jelte E

2016-03-01

This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and productivity. However, we here show that the envisaged scenarios all lead to an increased risk of motion sickness. As such, the benefits this technology is assumed to bring may not be capitalised on, in particular by those already susceptible to motion sickness. This can negatively affect user acceptance and uptake and, in turn, limit the potential socioeconomic benefits that this emerging technology may provide. Following a discussion on the causes of motion sickness in the context of self-driving cars, we present guidelines to steer the design and development of automated vehicle technologies. The aim is to limit or avoid the impact of motion sickness and ultimately promote the uptake of self-driving cars. Attention is also given to less well known consequences of motion sickness, in particular negative aftereffects such as postural instability, and detrimental effects on task performance and how this may impact the use and design of self-driving cars. We conclude that basic perceptual mechanisms need to be considered in the design process whereby self-driving cars cannot simply be thought of as living rooms, offices, or entertainment venues on wheels. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Predicting psychopharmacological drug effects on actual driving performance (SDLP) from psychometric tests measuring driving-related skills

OpenAIRE

Verster, Joris C.; Roth, Thomas

2011-01-01

Rationale There are various methods to examine driving ability. Comparisons between these methods and their relationship with actual on-road driving is often not determined. Objective The objective of this study was to determine whether laboratory tests measuring driving-related skills could adequately predict on-the-road driving performance during normal traffic. Methods Ninety-six healthy volunteers performed a standardized on-the-road driving test. Subjects were instructed to drive with a ...

Sequential Dependencies in Driving

Science.gov (United States)

Doshi, Anup; Tran, Cuong; Wilder, Matthew H.; Mozer, Michael C.; Trivedi, Mohan M.

2012-01-01

The effect of recent experience on current behavior has been studied extensively in simple laboratory tasks. We explore the nature of sequential effects in the more naturalistic setting of automobile driving. Driving is a safety-critical task in which delayed response times may have severe consequences. Using a realistic driving simulator, we find…

Driving automation forward : human factors for limited-ability autonomous driving systems.

Science.gov (United States)

2010-01-01

Over the past 100 years, there has been a : steady progression of innovations that : enhance the driving experience, in particular : the continuing trend toward automating more : driving tasks. Human Factors for Limited-Ability : Autonomous Drivin...

Linear step drive

International Nuclear Information System (INIS)

Haniger, L.; Elger, R.; Kocandrle, L.; Zdebor, J.

1986-01-01

A linear step drive is described developed in Czechoslovak-Soviet cooperation and intended for driving WWER-1000 control rods. The functional principle is explained of the motor and the mechanical and electrical parts of the drive, power control, and the indicator of position are described. The motor has latches situated in the reactor at a distance of 3 m from magnetic armatures, it has a low structural height above the reactor cover, which suggests its suitability for seismic localities. Its magnetic circuits use counterpoles; the mechanical shocks at the completion of each step are damped using special design features. The position indicator is of a special design and evaluates motor position within ±1% of total travel. A drive diagram and the flow chart of both the control electronics and the position indicator are presented. (author) 4 figs

High-power converters and AC drives

CERN Document Server

Wu, Bin

2017-01-01

This new edition reflects the recent technological advancements in the MV drive industry, such as advanced multilevel converters and drive configurations. It includes three new chapters, Control of Synchronous Motor Drives, Transformerless MV Drives, and Matrix Converter Fed Drives. In addition, there are extensively revised chapters on Multilevel Voltage Source Inverters and Voltage Source Inverter-Fed Drives. This book includes a systematic analysis on a variety of high-power multilevel converters, illustrates important concepts with simulations and experiments, introduces various megawatt drives produced by world leading drive manufacturers, and addresses practical problems and their mitigations methods.

Predicting Alcohol-Impaired Driving among Spanish Youth with the Theory of Reasoned Action.

Science.gov (United States)

Espada, José P; Griffin, Kenneth W; Gonzálvez, María T; Orgilés, Mireia

2015-06-19

Alcohol consumption is a risk factor for motor vehicle accidents in young drivers. Crashes associated with alcohol consumption typically have greater severity. This study examines the prevalence of driving under the influence among Spanish youth and tests the theory of reasoned action as a model for predicting driving under the influence. Participants included 478 Spanish university students aged 17-26 years. Findings indicated that alcohol was the substance most associated with impaired driving, and was involved in more traffic crashes. Men engage in higher levels of alcohol and other drug use, and perceived less risk in drunk driving (p reasoned action as a predictive model of driving under the influence of alcohol among youth in Spain (p < .001) and can help in the design of prevention programs.

Driving pleasure and perceptions of the transition from no automation to full self-driving automation

DEFF Research Database (Denmark)

Bjørner, Thomas

2018-01-01

In this article, I offer a sociological user perspective on increased self-driving automation, which has evolved from a long history associated with automobility. This study explores complex, perceived a priori driving pleasures in different scenarios involving self-driving cars. The methods used...... consisted of 32 in-depth interviews with participants who were given eight video examples (two video examples within four different scenarios) to watch. A numerical rating scales formed parts of the interviews. The findings revealed that driving pleasure when using increasingly automated driving...... technologies is very complex and must be seen within various contexts, including, for example, different speeds, road conditions, purposes, driving distances, and numbers of people in the car. Self-driving cars are not just about technology, increased safety, and better traffic flow, but are also dependent...

A Difficult Journey: Reflections on Driving and Driving Cessation From a Team of Clinical Researchers.

Science.gov (United States)

Liddle, Jacki; Gustafsson, Louise; Mitchell, Geoffrey; Pachana, Nancy A

2017-02-01

Recognizing the clinical importance and safety and well-being implications for the population, a multidisciplinary team has been researching older drivers and driving cessation issues for more than 15 years. Using empirical approaches, the team has explored quality of life and participation outcomes related to driving and nondriving for older people and has developed interventions to improve outcomes after driving cessation. The team members represent occupational therapists, medical practitioners, and clinical and neuropsychologists. While building the evidence base for driving- and driving cessation-related clinical practice, the researchers have also had first-hand experiences of interruptions to their own or parents' driving; involvement of older family members in road crashes; and provision of support during family members' driving assessment and cessation. This has led to reflection on their understandings and re-evaluation and refocusing of their perspectives in driving cessation research. This work will share the narratives of the authors and note their developing perspectives and foci within research as well as their clinical practice. Personal reflections have indicated the far-reaching implications for older drivers and family members of involvement in road crashes: the potential for interruptions to driving as a time for support and future planning and the conflicting and difficult roles of family members within the driving cessation process. Overall the lived, personal experience of the authors has reinforced the complex nature of driving and changes to driving status for the driver and their support team and the need for further research and support. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

System of didactic procedures to drive the teaching-learning of the computation in the half school level

Directory of Open Access Journals (Sweden)

Isabel Alonso-Berenguer

2016-09-01

Full Text Available A system of teaching methods is presented to drive the dynamics of the teaching-learning process of the Computation in the Half School Level, based on an interdisciplinary logic from cognitive nodes. This practical construct was designed using the Systemic-Structural-Functional method and was structured in two procedures, the relative to the appropriation of a computational culture and the concerning to the development of computational thinking, which in turn, are composed of a set of linked actions that are structured logically, that make possible the development of said dynamic. It also has evaluative criteria and patterns of achievement that allow for evaluation of the results obtained. The feasibility and relevance of the system of procedures was validated by conducting a socialization workshop with specialists of territory and through a survey of specialists from other provinces. Its application during the last two years has enabled its improvement.

Efficient Driving of Piezoelectric Transducers Using a Biaxial Driving Technique.

Directory of Open Access Journals (Sweden)

Samuel Pichardo

Full Text Available Efficient driving of piezoelectric materials is desirable when operating transducers for biomedical applications such as high intensity focused ultrasound (HIFU or ultrasound imaging. More efficient operation reduces the electric power required to produce the desired bioeffect or contrast. Our preliminary work [Cole et al. Journal of Physics: Condensed Matter. 2014;26(13:135901.] suggested that driving transducers by applying orthogonal electric fields can significantly reduce the coercivity that opposes ferroelectric switching. We present here the experimental validation of this biaxial driving technique using piezoelectric ceramics typically used in HIFU. A set of narrow-band transducers was fabricated with two sets of electrodes placed in an orthogonal configuration (following the propagation and the lateral mode. The geometry of the ceramic was chosen to have a resonance frequency similar for the propagation and the lateral mode. The average (± s.d. resonance frequency of the samples was 465.1 (± 1.5 kHz. Experiments were conducted in which each pair of electrodes was driven independently and measurements of effective acoustic power were obtained using the radiation force method. The efficiency (acoustic/electric power of the biaxial driving method was compared to the results obtained when driving the ceramic using electrodes placed only in the pole direction. Our results indicate that the biaxial method increases efficiency from 50% to 125% relative to the using a single electric field.

H1 antihistamines and driving.

Science.gov (United States)

Popescu, Florin Dan

2008-01-01

Driving performances depend on cognitive, psychomotor and perception functions. The CNS adverse effects of some H1 antihistamines can alter the patient ability to drive. Data from studies using standardized objective cognitive and psychomotor tests (Choice Reaction Time, Critical Flicker Fusion. Digital Symbol Substitution Test), functional brain imaging (Positron Emission Tomography, functional Magnetic Resonance Imaging), neurophysiological studies (Multiple Sleep Latency Test, auditory and visual evoked potentials), experimental simulated driving (driving simulators) and real driving studies (the Highway Driving Test, with the evaluation of the Standard Deviation Lateral Position, and the Car Following Test, with the measurement of the Brake Reaction Time) must be discussed in order to classify a H1 antihistamine as a true non-sedating one.

Superconducting cavity driving with FPGA controller

Energy Technology Data Exchange (ETDEWEB)

Czarski, T.; Koprek, W.; Pozniak, K.T.; Romaniuk, R.S. [Warsaw Univ. of Technology (Poland); Simrock, S.; Brand, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Chase, B.; Carcagno, R.; Cancelo, G. [Fermi National Accelerator Lab., Batavia, IL (United States); Koeth, T.W. [Rutgers - the State Univ. of New Jersey, NJ (United States)

2006-07-01

The digital control of several superconducting cavities for a linear accelerator is presented. The laboratory setup of the CHECHIA cavity and ACC1 module of the VU-FEL TTF in DESY-Hamburg have both been driven by a Field Programmable Gate Array (FPGA) based system. Additionally, a single 9-cell TESLA Superconducting cavity of the FNPL Photo Injector at FERMILAB has been remotely controlled from WUT-ISE laboratory with the support of the DESY team using the same FPGA control system. These experiments focused attention on the general recognition of the cavity features and projected control methods. An electrical model of the resonator was taken as a starting point. Calibration of the signal path is considered key in preparation for the efficient driving of a cavity. Identification of the resonator parameters has been proven to be a successful approach in achieving required performance; i.e. driving on resonance during filling and field stabilization during flattop time while requiring reasonable levels of power consumption. Feed-forward and feedback modes were successfully applied in operating the cavities. Representative results of the experiments are presented for different levels of the cavity field gradient. (orig.)

Superconducting cavity driving with FPGA controller

International Nuclear Information System (INIS)

Czarski, T.; Koprek, W.; Pozniak, K.T.; Romaniuk, R.S.; Simrock, S.; Brand, A.; Chase, B.; Carcagno, R.; Cancelo, G.; Koeth, T.W.

2006-01-01

The digital control of several superconducting cavities for a linear accelerator is presented. The laboratory setup of the CHECHIA cavity and ACC1 module of the VU-FEL TTF in DESY-Hamburg have both been driven by a Field Programmable Gate Array (FPGA) based system. Additionally, a single 9-cell TESLA Superconducting cavity of the FNPL Photo Injector at FERMILAB has been remotely controlled from WUT-ISE laboratory with the support of the DESY team using the same FPGA control system. These experiments focused attention on the general recognition of the cavity features and projected control methods. An electrical model of the resonator was taken as a starting point. Calibration of the signal path is considered key in preparation for the efficient driving of a cavity. Identification of the resonator parameters has been proven to be a successful approach in achieving required performance; i.e. driving on resonance during filling and field stabilization during flattop time while requiring reasonable levels of power consumption. Feed-forward and feedback modes were successfully applied in operating the cavities. Representative results of the experiments are presented for different levels of the cavity field gradient. (orig.)

Smartphone Based Approach For Monitoring Inefficient And Unsafe Driving Behavior And Recognizing Drink And Drive Conditions.

Directory of Open Access Journals (Sweden)

G. V. Mane

2015-08-01

Full Text Available Many automobile drivers having knowledge of the driving behaviours and habits that can lead to inefficient and unsafe driving. However it is often the case that these same drivers unknowingly manifest these inefficient and unsafe driving behaviours in their everyday driving activity. The proposed system proposes a practical and economical way to capture measure and alert drives of inefficient and unsafe driving as well as highly efficient system aimed at early detection and alert of dangerous vehicle maneuvers typically related to drunk driving. The upcoming solution consists of a mobile application running on a modern smartphone device paired with a compatible OBDII On-board diagnostics II reader.

Driving Competence in Mild Dementia with Lewy Bodies: In Search of Cognitive Predictors Using Driving Simulation

Directory of Open Access Journals (Sweden)

Stephanie Yamin

2015-01-01

Full Text Available Driving is a multifactorial behaviour drawing on multiple cognitive, sensory, and physical systems. Dementia is a progressive and degenerative neurological condition that impacts the cognitive processes necessary for safe driving. While a number of studies have examined driving among individuals with Alzheimer’s disease, less is known about the impact of Dementia with Lewy Bodies (DLB on driving safety. The present study compared simulated driving performance of 15 older drivers with mild DLB with that of 21 neurologically healthy control drivers. DLB drivers showed poorer performance on all indicators of simulated driving including an increased number of collisions in the simulator and poorer composite indicators of overall driving performance. A measure of global cognitive function (i.e., the Mini Mental State Exam was found to be related to the overall driving performance. In addition, measures of attention (i.e., Useful Field of View, UFOV and space processing (Visual Object and Space Perception, VOSP, Test correlated significantly with a rater’s assessment of driving performance.

Drive transmission system between a driving organ and a receiver organ

International Nuclear Information System (INIS)

Guillot, J.F.

1985-01-01

The present invention applies to the control rods of a water cooled nuclear reactor. The drive transmission system is disposed on the internal kinematic chain, between the control rod which is the receiver organ, and the driving organ. The control rod translation is obtained from a motion of rotation transformed in a motion of translation by means of a screw-nut system. The present invention prevents from control rod ejection in case of depressurization of the vessel containing the control rod drives or in case of reactor upsetting when it is embarked [fr

Analysis of national pay-as-you-drive insurance systems and other variable driving charges

Energy Technology Data Exchange (ETDEWEB)

Wenzel, T.

1995-07-01

Under Pay as You Drive insurance (PAYD), drivers would pay part of their automobile insurance premium as a per-gallon surcharge every time they filled their gas tank. By transfering a portion of the cost of owning a vehicle from a fixed cost to a variable cost, PAYD would discourage driving. PAYD has been proposed recently in California as a means of reforming how auto insurance is provided. PAYD proponents claim that, by forcing drivers to purchase at least part of their insurance every time they refuel their car, PAYD would reduce or eliminate the need for uninsured motorist coverage. Some versions of PAYD proposed in California have been combined with a no-fault insurance system, with the intention of further reducing premiums for the average driver. Other states have proposed PAYD systems that would base insurance premiums on annual miles driven. In this report we discuss some of the qualitative issues surrounding adoption of PAYD and other policies that would convert other fixed costs of driving (vehicle registration, safety/emission control system inspection, and driver license renewal) to variable costs. We examine the effects of these policies on two sets of objectives: objectives related to auto insurance reform, and those related to reducing fuel consumption, CO{sub 2} emissions, and vehicle miles traveled. We pay particular attention to the first objective, insurance reform, since this has generated the most interest in PAYD to date, at least at the state level.

Driving things

DEFF Research Database (Denmark)

Nevile, Maurice Richard

2015-01-01

I explore how participants organise involvement with objects brought into the car, relative to the demands of driving and social activity. Objects in cars commonly include phones or other technologies, food, body care products, texts, clothing, bags and carry items, toys, and even animals...... 2004, Haddington et al. 2012). I focus here especially on how the practical and interactional work of locating, seeing, placing, handling, hearing, and relinquishing, is ordered and accomplished relative to the emerging and contingent demands of both driving and social participation......, such that involvement with objects is constituted as secondary to driving in a multiactivity setting (e.g. Haddington et al. 2014). We see how events with, for, of, and even by objects can occur as predictable, planned and even designed for (e.g. changing glasses, applying body lotion), or might be unexpected...

Real-world European driving cycles, for measuring pollutant emissions from high- and low-powered cars

OpenAIRE

ANDRE, Michel; JOUMARD, Robert; VIDON, Robert; TASSEL, Patrick; PERRET, Pascal

2006-01-01

Pollutant emissions from cars are usually measured on a test bench using driving cycles. However, the use of one unique set of driving cycles to test all cars can be seen as a weak point of emission estimation, as vehicles could conceivably be tested differently depending on their performance levels and usage characteristics. A specific study was then conducted to characterize driving conditions and vehicle usage as a function of vehicle categories, as well as to derive driving cycles special...

The impact of therapeutic opioid agonists on driving-related psychomotor skills assessed by a driving simulator or an on-road driving task: A systematic review.

Science.gov (United States)

Ferreira, Diana H; Boland, Jason W; Phillips, Jane L; Lam, Lawrence; Currow, David C

2018-04-01

Driving cessation is associated with poor health-related outcomes. People with chronic diseases are often prescribed long-term opioid agonists that have the potential to impair driving. Studies evaluating the impact of opioids on driving-related psychomotor skills report contradictory results likely due to heterogeneous designs, assessment tools and study populations. A better understanding of the effects of regular therapeutic opioid agonists on driving can help to inform the balance between individual's independence and community safety. To identify the literature assessing the impact of regular therapeutic opioid agonists on driving-related psychomotor skills for people with chronic pain or chronic breathlessness. Systematic review reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis statement; PROSPERO Registration CRD42017055909. Six electronic databases and grey literature were systematically searched up to January, 2017. Inclusion criteria were as follows: (1) empirical studies reporting data on driving simulation, on-the-road driving tasks or driving outcomes; (2) people with chronic pain or chronic breathlessness; and (3) taking regular therapeutic opioid agonists. Critical appraisal used the National Institutes of Health's quality assessment tools. From 3809 records screened, three studies matched the inclusion criteria. All reported data on people with chronic non-malignant pain. No significant impact of regular therapeutic opioid agonists on people's driving-related psychomotor skills was reported. One study reported more intense pain significantly worsened driving performance. This systematic review does not identify impaired simulated driving performance when people take regular therapeutic opioid agonists for symptom control, although more prospective studies are needed.

Effect of consecutive driving on accident risk: a comparison between passenger and freight train driving.

Science.gov (United States)

Chang, Hsin-Li; Ju, Lai-Shun

2008-11-01

This study combined driver-responsible accidents with on-board driving hours to examine the effect of consecutive driving on the accident risk of train operations. The data collected from the Taiwan Railway Administration for the period 1996-2006 was used to compute accident rates for varied accumulated driving hours for passenger and freight trains. The results showed that accident risk grew with increased consecutive driving hours for both passenger and freight trains, and doubled that of the first hour after four consecutive hours of driving. Additional accident risk was found for freight trains during the first hour due to required shunting in the marshalling yards where there are complex track layouts and semi-automatic traffic controls. Also, accident risk for train driving increased more quickly over consecutive driving hours than for automobile driving, and accumulated fatigue caused by high working pressure and monotony of the working environment are considered to be the part of the reason. To prevent human errors accidents, enhancing safety equipment, driver training programs, and establishing a sound auditing system are suggested and discussed.

Creating a driving profile for older adults using GPS devices and naturalistic driving methodology [version 1; referees: 2 approved, 1 approved with reservations

Directory of Open Access Journals (Sweden)

Ganesh M. Babulal

2016-09-01

Full Text Available Background/Objectives: Road tests and driving simulators are most commonly used in research studies and clinical evaluations of older drivers. We adapted an existing, commercial, off-the-shelf, in-vehicle device for naturalistic, longitudinal research to better understand daily driving behavior in older drivers. Design: The Azuga G2 Tracking DeviceTM was installed in each participant’s vehicle, and we collected data over 5 months (speed, latitude/longitude every 30-seconds when the vehicle was driven.  Setting: The Knight Alzheimer’s Disease Research Center at Washington University School of Medicine. Participants: Five individuals enrolled in a larger, longitudinal study assessing preclinical Alzheimer disease and driving performance.  Participants were aged 65+ years and had normal cognition. Measurements:  Spatial components included Primary Location(s, Driving Areas, Mean Centers and Unique Destinations.  Temporal components included number of trips taken during different times of the day.  Behavioral components included number of hard braking, speeding and sudden acceleration events. Methods:  Individual 30-second observations, each comprising one breadcrumb, and trip-level data were collected and analyzed in R and ArcGIS.  Results: Primary locations were confirmed to be 100% accurate when compared to known addresses.  Based on the locations of the breadcrumbs, we were able to successfully identify frequently visited locations and general travel patterns.  Based on the reported time from the breadcrumbs, we could assess number of trips driven in daylight vs. night.  Data on additional events while driving allowed us to compute the number of adverse driving alerts over the course of the 5-month period. Conclusions: This pilot study indicated that Driving Profiles for older adults can be created and compared month-to-month or year-to-year, allowing researchers to identify changes in driving patterns that are unavailable in

Exploring two-dimensional electron gases with two-dimensional Fourier transform spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Paul, J.; Dey, P.; Karaiskaj, D., E-mail: karaiskaj@usf.edu [Department of Physics, University of South Florida, 4202 East Fowler Ave., Tampa, Florida 33620 (United States); Tokumoto, T.; Hilton, D. J. [Department of Physics, University of Alabama at Birmingham, Birmingham, Alabama 35294 (United States); Reno, J. L. [CINT, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

2014-10-07

The dephasing of the Fermi edge singularity excitations in two modulation doped single quantum wells of 12 nm and 18 nm thickness and in-well carrier concentration of ∼4 × 10{sup 11} cm{sup −2} was carefully measured using spectrally resolved four-wave mixing (FWM) and two-dimensional Fourier transform (2DFT) spectroscopy. Although the absorption at the Fermi edge is broad at this doping level, the spectrally resolved FWM shows narrow resonances. Two peaks are observed separated by the heavy hole/light hole energy splitting. Temperature dependent “rephasing” (S{sub 1}) 2DFT spectra show a rapid linear increase of the homogeneous linewidth with temperature. The dephasing rate increases faster with temperature in the narrower 12 nm quantum well, likely due to an increased carrier-phonon scattering rate. The S{sub 1} 2DFT spectra were measured using co-linear, cross-linear, and co-circular polarizations. Distinct 2DFT lineshapes were observed for co-linear and cross-linear polarizations, suggesting the existence of polarization dependent contributions. The “two-quantum coherence” (S{sub 3}) 2DFT spectra for the 12 nm quantum well show a single peak for both co-linear and co-circular polarizations.

Self-driving carsickness

NARCIS (Netherlands)

Diels, C.; Bos, J.E.

2016-01-01

This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and

Self-driving carsickness.

NARCIS (Netherlands)

Diels, C.; Bos, J.E.

2016-01-01

This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and

Antihistamines and driving safety.

Science.gov (United States)

O'Hanlon, J F

1988-10-27

The results of two placebo-controlled driving performance studies confirm laboratory data showing that the nonsedating antihistamine terfenadine does not influence the driving performance of users. The amplitude of vehicle weaving calculated for drivers who received this agent did not differ from control values. Neither terfenadine nor loratadine, another nonsedating antihistamine, potentiated the adverse effects of alcohol on driving performance.

Modulational instability development and current drive

International Nuclear Information System (INIS)

Popel, S.I.; Vladimirov, S.V.; Tsytovich, V.N.

1992-01-01

Recently many investigations on current driven by lower-hybrid (LH) waves in a plasma of toroidal nuclear fusion installations are carried out. Usually a theoretical approach taking into account quasilinear and binary collisions effects is used to describe current drive. However a problem of comparison of the results obtained with the aid of the above theoretical approach and experimental data takes place. Namely the experimentally observed currents driven by LH waves is two-three orders of magnitude larger than those calculated. The above discrepancy between theory and experiment is related with the existence of the so-called ''spectral gap'', that is the gap between the parallel phase velocities of LH waves ω/k || (where ω, k || are LH wave frequency and a component of wavenumber k parallel to the external magnetic field) which are necessary for effective Landau damping of LH waves (i.e. velocities as high as several electron thermal velocities) and the lowest parallel phase velocity in the injected LH wave spectrum. Experimentally observed current drive may be explained if one accounts for filling of the ''spectral gap'' by LH waves. Some nonlinear effects have been drawn in current drive description to explain the ''spectral gap'' filling by LH waves. However the LH wave modulational instability (MI) effect has not been considered yet in application to current drive description. The aim of this paper is to investigate this MI influence. We shall show that for sufficiently intensive pump level of LH wave the MI can lead to ''spectral gap'' filling. (author) 4 refs

Enhancing Quantum Discord in Cavity QED by Applying Classical Driving Field

International Nuclear Information System (INIS)

Qian Yi; Xu Jing-Bo

2012-01-01

We investigate the quantum discord dynamics in a cavity quantum electrodynamics system, which consists of two noninteracting two-level atoms driven by independent optical fields and classical fields, and find that the quantum discord vanishes only asymptotically although entanglement disappears suddenly during the time evolution in the absence of classical fields. It is shown that the amount of quantum discord can be increased by adjusting the classical driving fields because the increasing degree of the amount of quantum mutual information is greater than classical correlation by applying the classical driving fields. Finally, the influence of the classical driving field on the fidelity of the system is also examined. (general)

Analysis of Harmonics Suppression by Active Damping Control on Multi Slim DC-link Drives

DEFF Research Database (Denmark)

Yang, Feng; Máthé, Lászlo; Lu, Kaiyuan

2016-01-01

Compared with conventional dc-link drive, slim dc-link drive is expected to achieve lower cost and longer life time. However, harmonics distortion problem may occur in such drive systems. This paper proposes to use an active damping control method to suppress the harmonic distortion...... with the benefit of low cost and also low loss. A new analysis method, based on the frequency domain impedance model, is presented to explore the mechanism of harmonics suppression. Also, a general method is presented to build the impedance model of a PMSM drive system using Field Oriented Control (FOC) method....... Some design issues, including power levels, current control bandwidth and harmonic interaction, are discussed when the drive system is fed by a weak grid. Case studies on a two-drive system composed by two slim dc-link drive units are provided to verify the proposed analysis method....

Parental perceptions of teen driving: Restrictions, worry and influence☆

Science.gov (United States)

Jewett, Amy; Shults, Ruth A.; Bhat, Geeta

2016-01-01

Introduction Parents play a critical role in preventing crashes among teens. Research of parental perceptions and concerns regarding teen driving safety is limited. We examined results from the 2013 Summer ConsumerStyles survey that queried parents about restrictions placed on their teen drivers, their perceived level of “worry” about their teen driver’s safety, and influence of parental restrictions regarding their teen’s driving. Methods We produced frequency distributions for the number of restrictions imposed, parental “worry,” and influence of rules regarding their teen’s driving, reported by teen’s driving license status (learning to drive or obtained a driver’s license). Response categories were dichotomized because of small cell sizes, and we ran separate log-linear regression models to explore whether imposing all four restrictions on teen drivers was associated with either worry intensity (“a lot” versus “somewhat, not very much or not at all”) or perceived influence of parental rules (“a lot” versus “somewhat, not very much or not at all”). Results Among the 456 parent respondents, 80% reported having restrictions for their teen driver regarding use of safety belts, drinking and driving, cell phones, and text messaging while driving. However, among the 188 parents of licensed teens, only 9% reported having a written parent-teen driving agreement, either currently or in the past. Worrying “a lot” was reported less frequently by parents of newly licensed teens (36%) compared with parents of learning teens (61%). Conclusions and Practical Applications Parents report having rules and restrictions for their teen drivers, but only a small percentage formalize the rules and restrictions in a written parent-teen driving agreement. Parents worry less about their teen driver’s safety during the newly licensed phase, when crash risk is high as compared to the learning phase. Further research is needed into how to effectively

The association between personality and aggressive driving: A meta-analysis

Directory of Open Access Journals (Sweden)

Alina E. Iancu

2016-12-01

Full Text Available The aim of the present paper was to synthesize previous results on the relationship between personality (from the perspective of the Big Five Model and Alternative Five model and aggressive driving. Secondly, we aimed at identifying the model of personality with the highest level of association to aggressive driving. The statistical analyses were conducted exclusively for those dimensions of personality that overlap (i.e., Neuroticism vs. Neuroticism-Anxiety, Extraversion vs. Sociability, Agreeableness vs. Aggression - Hostility. We searched for empirical studies with (1 cross-sectional design, (2 all the data needed for the meta-analytical computations, and (3 written in English. Database searches revealed a sample of 78 articles out of which 16 were eligible. The total sample of participants was of 6,721. Using a random effects framework, regarding the Big Five Model, we found a weak effect size for the relationship between Neuroticism and aggressive driving (r = .26, p < .001, a very weak relationship between Extraversion and aggressive driving (r = .07, p = .03, and a weak effect size for Agreeableness and aggressive driving (r = -.26, p < .001. Regarding the Alternative Five model, we identified a weak effect size for Neuroticism – Anxiety (r = .21, p = .05, marginally significant and weak effect for Sociability (r = .21, p = .06, and a moderate effect size for Aggression – Hostility and aggressive driving (r = .41, p = .00. The comparison between the two models of personality revealed that the AFM is more related to aggressive driving than BFM.

Predicting drive for muscularity behavioural engagement from body image attitudes and emotions.

Science.gov (United States)

Tod, David; Edwards, Christian

2013-01-01

We examined the potential moderating effects of appearance investment, body image disturbance, and situational body image dysphoria on the drive for muscularity attitude-behaviour relationship. Participants (339 British college men, M(AGE)=20.00 years, SD=2.59) completed drive for muscularity attitude and behaviour, appearance investment, body image disturbance, and situational body image dysphoria measures. Results indicated higher levels of appearance investment, body image disturbance, and situational body image dysphoria were associated with increases in the drive for muscularity attitude's relationship with physique-enhancing behavioural engagement. Results help extend recent research that has moved beyond identifying correlates to examining ways that groups of variables interact to predict drive for muscularity behavioural engagement and may contribute to theory development. Copyright © 2012 Elsevier Ltd. All rights reserved.

Wrong-way driving.

NARCIS (Netherlands)

2006-01-01

Wrong-way driving is a phenomenon that mainly happens on motorways. Although the number of wrong-way crashes is relatively limited, their consequences are much more severe than the consequences of other motorway injury crashes. The groups most often causing wrong-way driving accidents are young,

Older Drivers' Reasons for Reducing the Overall Amount of Their Driving and for Avoiding Selected Driving Situations

DEFF Research Database (Denmark)

Meng, Annette; Siren, Anu Kristiina

2015-01-01

that the reduction in driving and avoidance of driving situations are separate types of self-regulatory behavior; that self-regulation of driving is an automatic process, in which older drivers are not aware that they are compensating for functional loss; and that it is important to acknowledge gender differences......Structured telephone interviews were conducted with 840 older drivers to explore their reasons for self-regulating their driving. The main reason for reduced driving was having fewer activities to drive to, and for avoidance of driving situations, reasons also included not liking or feeling...

Automobile driving in older adults: factors affecting driving restriction in men and women.

Science.gov (United States)

Marie Dit Asse, Laetitia; Fabrigoule, Colette; Helmer, Catherine; Laumon, Bernard; Lafont, Sylviane

2014-11-01

To identify factors associated with driving restriction in elderly men and women. Prospective cohort study of French drivers from 2003 to 2009. The Three-City Cohort of Bordeaux, a prospective study of 2,104 people aged 65 and older. Five hundred twenty-three drivers with a mean age of 76 (273 male, 250 female). Sociodemographic characteristics, driving habits, health variables, cognitive evaluation and dementia diagnosis. Predementia was defined as no dementia at one follow-up and dementia at the next follow-up. Over the 6-year period, 54% of men and 63% of women stopped driving or reduced the distance they drove. Predementia, Parkinson's disease, older age, and a high number of kilometers previously driven were common restriction factors in both sexes. Prevalent dementia, depressive symptomatology, a decline in one or more instrumental activities of daily living, and poor visual working memory were specific factors in men. In women, low income, fear of falling, slow processing speed, and severe decline in global cognitive performance all affected driving restriction. Older women restricted their driving activity more than older men, regardless of the number of kilometers previously driven, physical health, and cognitive status. Factors affecting driving restriction differed according to sex, and women were more likely to stop driving than men in the period preceding a dementia diagnosis. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

Preliminary report of the Hepatic Encephalopathy Assessment Driving Simulator (HEADS) score.

Science.gov (United States)

Baskin-Bey, Edwina S; Stewart, Charmaine A; Mitchell, Mary M; Bida, John P; Rosenthal, Theodore J; Nyberg, Scott L

2008-01-01

Audiovisual simulations of real-life driving (ie, driving simulators) have been used to assess neurologic dysfunction in a variety of medical applications. However, the use of simulated driving to assess neurologic impairment in the setting of liver disease (ie, hepatic encephalopathy) is limited. The aim of this analysis was to develop a scoring system based on simulated driving performance to assess mild cognitive impairment in cirrhotic patients with hepatic encephalopathy. This preliminary analysis was conducted as part of the Hepatic Encephalopathy Assessment Driving Simulator (HEADS) pilot study. Cirrhotic volunteers initially underwent a battery of neuropsychological tests to identify those cirrhotic patients with mild cognitive impairment. Performance during an audiovisually simulated course of on-road driving was then compared between mildly impaired cirrhotic patients and healthy volunteers. A scoring system was developed to quantify the likelihood of cognitive impairment on the basis of data from the simulated on-road driving. Mildly impaired cirrhotic patients performed below the level of healthy volunteers on the driving simulator. Univariate logistic regression and correlation models indicated that several driving simulator variables were significant predictors of cognitive impairment. Five variables (run time, total map performance, number of collisions, visual divided attention response, and average lane position) were incorporated into a quantitative model, the HEADS scoring system. The HEADS score (0-9 points) showed a strong correlation with cognitive impairment as measured by area under the receiver-operator curve (.89). The HEADS system appears to be a promising new tool for the assessment of mild hepatic encephalopathy.

Comparing Expert Driving Behavior in Real World and Simulator Contexts

Directory of Open Access Journals (Sweden)

Hiran B. Ekanayake

2013-01-01

Full Text Available Computer games are increasingly used for purposes beyond mere entertainment, and current hi-tech simulators can provide quite, naturalistic contexts for purposes such as traffic education. One of the critical concerns in this area is the validity or transferability of acquired skills from a simulator to the real world context. In this paper, we present our work in which we compared driving in the real world with that in the simulator at two levels, that is, by using performance measures alone, and by combining psychophysiological measures with performance measures. For our study, we gathered data using questionnaires as well as by logging vehicle dynamics, environmental conditions, video data, and users' psychophysiological measurements. For the analysis, we used several novel approaches such as scatter plots to visualize driving tasks of different contexts and to obtain vigilance estimators from electroencephalographic (EEG data in order to obtain important results about the differences between the driving in the two contexts. Our belief is that both experimental procedures and findings of our experiment are very important to the field of serious games concerning how to evaluate the fitness of driving simulators and measure driving performance.

Driving with the wandering mind: the effect that mind-wandering has on driving performance.

Science.gov (United States)

Yanko, Matthew R; Spalek, Thomas M

2014-03-01

The principal objective of the present work was to examine the effects of mind state (mind-wandering vs. on-task) on driving performance in a high-fidelity driving simulator. Mind-wandering is thought to interfere with goal-directed thought. It is likely, then, that when driving, mind-wandering might lead to impairments in critical aspects of driving performance. In two experiments, we assess the extent to which mind-wandering interferes with responsiveness to sudden events, mean velocity, and headway distance. Using a car-following procedure in a high-fidelity driving simulator, participants were probed at random times to indicate whether they were on-task at that moment or mind-wandering. The dependent measures were analyzed based on the participant's response to the probe. Compared to when on-task, when mind-wandering participants showed longer response times to sudden events, drove at a higher velocity, and maintained a shorter headway distance. Collectively, these findings indicate that mind-wandering affects a broad range of driving responses and may therefore lead to higher crash risk. The results suggest that situations that are likely associated with mind-wandering (e.g., route familiarity) can impair driving performance.

Harmonic Coupling Analysis of a Multi-Drive System with Slim DC-link Drive

DEFF Research Database (Denmark)

Yang, Feng; Kwon, Jun Bum; Blaabjerg, Frede

2017-01-01

One of the problems with slim dc-link adjustable speed drive is the difficulties to analyze the harmonic coupling when it is integrated into a multi-drive system. The traditional methods analyze this harmonic issue by neglecting the harmonic coupling, and base on the linear time-invariant methods....... Its disadvantages include the time consumption and large computer memory. This paper proposes to do harmonic analysis by using the harmonic state-space modeling method by using the linear time-periodic theory. By using the proposed model, the harmonic couplings, between dc-link and point of common...... coupling in different drives, are all analyzed in the multi-drive system. In the meantime, the effects of the small film dc-link capacitance and the nonlinear characteristic of the diode rectifier are considered. The detailed modeling procedure, the simulations and the lab experiment on a two-drive system...

Method for driving an actuator, actuator drive, and apparatus comprising an actuator

OpenAIRE

2010-01-01

An actuator driver circuit includes a drive signal source and an electrical damping element having a negative resistance connected in series with the drive signal source. A controllable switch is provided for selectively switching the electrical damping element into or put of a signal path from a drive signal source output to a driver circuit output, in order to selectively change the electrical damping of an actuator. For example, the electrical damping of a radial actuator or a focus actuat...

Modeling Driving Behavior at Roundabouts: Impact of Roundabout Layout and Surrounding Traffic on Driving Behavior

OpenAIRE

Zhao, Min; Käthner, David; Söffker, Dirk; Jipp, Meike; Lemmer, Karsten

2017-01-01

Driving behavior prediction at roundabouts is an important challenge to improve driving safety by supporting drivers with intelligent assistance systems. To predict the driving behavior effciently steering wheel status was proven to have robust predictability based on a Support Vector Machine algorithm. Previous research has not considered potential effects of roundabout layout and surrounding traffic on driving behavior, but that consideration can certainly improve the prediction results....

Crash avoidance in response to challenging driving events: The roles of age, serialization, and driving simulator platform.

Science.gov (United States)

Bélanger, Alexandre; Gagnon, Sylvain; Stinchcombe, Arne

2015-09-01

We examined the crash avoidance behaviors of older and middle-aged drivers in reaction to six simulated challenging road events using two different driving simulator platforms. Thirty-five healthy adults aged 21-36 years old (M=28.9±3.96) and 35 healthy adults aged 65-83 years old (M=72.1±4.34) were tested using a mid-level simulator, and 27 adults aged 21-38 years old (M=28.6±6.63) and 27 healthy adults aged 65-83 years old (M=72.7±5.39) were tested on a low-cost desktop simulator. Participants completed a set of six challenging events varying in terms of the maneuvers required, avoiding space given, directional avoidance cues, and time pressure. Results indicated that older drivers showed higher crash risk when events required multiple synchronized reactions. In situations that required simultaneous use of steering and braking, older adults tended to crash significantly more frequently. As for middle-aged drivers, their crashes were attributable to faster driving speed. The same age-related driving patterns were observed across simulator platforms. Our findings support the hypothesis that older adults tend to react serially while engaging in cognitively challenging road maneuvers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Factors That Drive Youth Specialization.

Science.gov (United States)

Padaki, Ajay S; Popkin, Charles A; Hodgins, Justin L; Kovacevic, David; Lynch, Thomas Sean; Ahmad, Christopher S

Specialization in young athletes has been linked to overuse injuries, burnout, and decreased satisfaction. Despite continued opposition from the medical community, epidemiological studies suggest the frequency is increasing. Extrinsic pressures in addition to individual aspirations drive this national trend in sports specialization. Descriptive epidemiology study. Level 3. A novel instrument assessing the driving factors behind youth specialization was generated by an interdisciplinary team of medical professionals. Surveys were administered to patients and athletes in the department's sports medicine clinic. The survey was completed by 235 athletes between 7 and 18 years of age, with a mean age of 13.8 ± 3.0 years. Athletes specialized at a mean age of 8.1 years, and 31% of athletes played a single sport while 58% played multiple sports but had a preferred sport. More than 70% of athletes had collegiate or professional ambitions, and 60% played their primary sport for 9 or more months per year, with players who had an injury history more likely to play year-round ( P specialized athletes reporting this significantly more often ( P = 0.04). Half of the athletes reported that sports interfered with their academic performance, with older players stating this more frequently ( P specializing in a single sport before starting high school. While intrinsic drive may identify healthy aspirations, extrinsic influences are prevalent in specialized athletes. Extrinsic factors contributing to youth specialization were identified and compounded the deleterious sequelae of youth athlete specialization.

A comparison of the effect of mobile phone use and alcohol consumption on driving simulation performance.

Science.gov (United States)

Leung, Sumie; Croft, Rodney J; Jackson, Melinda L; Howard, Mark E; McKenzie, Raymond J

2012-01-01

The present study compared the effects of a variety of mobile phone usage conditions to different levels of alcohol intoxication on simulated driving performance and psychomotor vigilance. Twelve healthy volunteers participated in a crossover design in which each participant completed a simulated driving task on 2 days, separated by a 1-week washout period. On the mobile phone day, participants performed the simulated driving task under each of 4 conditions: no phone usage, a hands-free naturalistic conversation, a hands-free cognitively demanding conversation, and texting. On the alcohol day, participants performed the simulated driving task at four different blood alcohol concentration (BAC) levels: 0.00, 0.04, 0.07, and 0.10. Driving performance was assessed by variables including time within target speed range, time spent speeding, braking reaction time, speed deviation, and lateral lane position deviation. In the BAC 0.07 and 0.10 alcohol conditions, participants spent less time in the target speed range and more time speeding and took longer to brake in the BAC 0.04, 0.07, and 0.10 than in the BAC 0.00 condition. In the mobile phone condition, participants took longer to brake in the natural hands-free conversation, cognitively demanding hands-free conversation and texting conditions and spent less time in the target speed range and more time speeding in the cognitively demanding, hands-free conversation, and texting conditions. When comparing the 2 conditions, the naturalistic conversation was comparable to the legally permissible BAC level (0.04), and the cognitively demanding and texting conversations were similar to the BAC 0.07 to 0.10 results. The findings of the current laboratory study suggest that very simple conversations on a mobile phone may not represent a significant driving risk (compared to legally permissible BAC levels), whereas cognitively demanding, hands-free conversation, and particularly texting represent significant risks to driving.

Resource diversity and landscape-level homogeneity drive native bee foraging.

Science.gov (United States)

Jha, Shalene; Kremen, Claire

2013-01-08

Given widespread declines in pollinator communities and increasing global reliance on pollinator-dependent crops, there is an acute need to develop a mechanistic understanding of native pollinator population and foraging biology. Using a population genetics approach, we determine the impact of habitat and floral resource distributions on nesting and foraging patterns of a critical native pollinator, Bombus vosnesenskii. Our findings demonstrate that native bee foraging is far more plastic and extensive than previously believed and does not follow a simple optimal foraging strategy. Rather, bumble bees forage further in pursuit of species-rich floral patches and in landscapes where patch-to-patch variation in floral resources is less, regardless of habitat composition. Thus, our results reveal extreme foraging plasticity and demonstrate that floral diversity, not density, drives bee foraging distance. Furthermore, we find a negative impact of paved habitat and a positive impact of natural woodland on bumble bee nesting densities. Overall, this study reveals that natural and human-altered landscapes can be managed for increased native bee nesting and extended foraging, dually enhancing biodiversity and the spatial extent of pollination services.

Isolation and functional characterization of a cotton ubiquitination-related promoter and 5'UTR that drives high levels of expression in root and flower tissues

Directory of Open Access Journals (Sweden)

Viana Antonio AB

2011-11-01

Full Text Available Abstract Background Cotton (Gossypium spp. is an important crop worldwide that provides raw material to 40% of the textile fiber industry. Important traits have been studied aiming the development of genetically modified crops including resistance to insect and diseases, and tolerance to drought, cold and herbicide. Therefore, the characterization of promoters and regulatory regions is also important to achieve high gene expression and/or a specific expression pattern. Commonly, genes involved in ubiquitination pathways are highly and differentially expressed. In this study, we analyzed the expression of a cotton ubiquitin-conjugating enzyme (E2 family member with no previous characterization. Results Nucleotide analysis revealed high identity with cotton E2 homologues. Multiple alignment showed a premature stop codon, which prevents the encoding of the conserved cysteine residue at the E2 active site, and an intron that is spliced in E2 homologues, but not in GhGDRP85. The GhGDRP85 gene is highly expressed in different organs of cotton plants, and has high transcript levels in roots. Its promoter (uceApro2 and the 5'UTR compose a regulatory region named uceA1.7, and were isolated from cotton and studied in Arabidopsis thaliana. uceA1.7 shows strong expression levels, equaling or surpassing the expression levels of CaMV35S. The uceA1.7 regulatory sequence drives GUS expression 7-fold higher in flowers, 2-fold in roots and at similar levels in leaves and stems. GUS expression levels are decreased 7- to 15-fold when its 5'UTR is absent in uceApro2. Conclusions uceA1.7 is a strong constitutive regulatory sequence composed of a promoter (uceApro2 and its 5'UTR that will be useful in genetic transformation of dicots, having high potential to drive high levels of transgene expression in crops, particularly for traits desirable in flower and root tissues.

Road Safety Data, Collection, Transfer and Analysis DaCoTa. Workpackage 6, Driver Behaviour Monitoring through Naturalistic Driving: Deliverable 6.5: Naturalistic Driving for cross-national monitoring of SPIs and Exposure : an overview.

NARCIS (Netherlands)

Wegman, R.W.N. & Bos, N.M.

2015-01-01

WP6 of DaCoTA, Driver Behaviour Monitoring through Naturalistic Driving, focuses on the usefulness and feasibility of applying the Naturalistic Driving method for monitoring within the framework of ERSO. The aim is to continuously collect comparable information about the road safety level in EU

Driving styles among young novice drivers--the contribution of parental driving styles and personal characteristics.

Science.gov (United States)

Miller, Gila; Taubman-Ben-Ari, Orit

2010-03-01

As part of the effort to ascertain why young drivers are more at risk for car crashes, attention has recently turned to the effects of family, including the intergenerational transmission of driving styles from parents to offspring. The current study sought to further understanding of the nature and aspects of the family influence with the help of Bowen's family systems theory. In Phase 1 of the prospective study, 130 young driving students completed questionnaires tapping personal and personality measures, and their parents completed driving-related instruments. In Phase 2, a year after the young drivers had obtained their driver's license, they were administered the same questionnaires their parents had previously completed. The results show significant correlations between the parents' driving styles and those of their offspring a year after licensure. Furthermore, differentiation of self and self-efficacy in newly acquired driving skills were found to moderate or heighten the similarity between the driving styles of parents and their offspring. For young drivers reporting anxiety in Phase 1, this was associated with a reported anxious driving style a year later. Among young female drivers, anxiety was also associated with a reckless and careless style. Higher sensation seeking was related to higher reckless driving among young male drivers. The findings are discussed in the context of adolescence and the role of the study variables in the development and intergenerational transmission of driving styles. In addition to its theoretical contribution to the realms of intergenerational transmission in general, and young drivers in particular, the study may have practical implications for both family therapy and the design of driving interventions. Copyright 2009 Elsevier Ltd. All rights reserved.

Impaired-driving prevalence among US high school students: associations with substance use and risky driving behaviors.

Science.gov (United States)

Li, Kaigang; Simons-Morton, Bruce G; Hingson, Ralph

2013-11-01

We examined the prevalence of impaired driving among US high school students and associations with substance use and risky driving behavior. We assessed driving while alcohol or drug impaired (DWI) and riding with alcohol- or drug-impaired drivers (RWI) in a nationally representative sample of 11th-grade US high school students (n = 2431). We examined associations with drinking and binge drinking, illicit drug use, risky driving, and demographic factors using multivariate sequential logistic regression analysis. Thirteen percent of 11th-grade students reported DWI at least 1 of the past 30 days, and 24% reported RWI at least once in the past year. Risky driving was positively associated with DWI (odds ratio [OR] = 1.25; P phone calls (OR = 3.2) while driving. Our findings suggest the need for comprehensive approaches to the prevention of DWI, RWI, and other risky driving behavior.

Motorcycle On-Road Driving Parameters Influencing Fuel Consumption and Emissions on Congested Signalized Urban Corridor

Directory of Open Access Journals (Sweden)

Atthapol Seedam

2017-01-01

Full Text Available This study aims to find the on-road driving parameters influencing fuel consumption and emissions of motorcycle driving on a congested signalized urban corridor. A motorcycle onboard measurement system was developed to measure instantaneously and continuously record on-road driving data, including speed-time profile, emissions, and fuel consumption, by the second. The test motorcycles were driven by 30 sample motorcyclists on a signalized urban corridor in Khon Kaen City, Thailand, to collect their on-road driving behavior during the morning peak period. Cluster analysis was applied to analyze collected driving data and to categorize the drivers by level of fuel consumption and on-road driver behavior. The on-road driving parameter influencing fuel consumption and emissions was then determined. Results revealed that proportion of idle time significantly influenced fuel consumption and emissions of motorcycle driving on a congested signalized urban corridor, though aggressive driving behavior, hard acceleration and deceleration, did not have the same kind of influence.

Influence of bicarbonate on ventilatory drive in healthy subjects

NARCIS (Netherlands)

Mos-Oppersma, Eline; Doorduin, Jonne; van der Hoeven, J.G.; Veltink, Peter; Heunks, Leo M.A.

2016-01-01

Background Acute hypoventilation results in CO2 retention and respiratory acidosis. Bicarbonate retention aims to restore pH level. However, after institution of mechanical ventilation metabolic alkalosis may develop, which could impair respiratory drive. Aim To investigate whether increased plasma

[Personality traits of drivers serving a custodial sentence for drink driving].

Science.gov (United States)

Pawłowska, Beata; Rzeszutko, Ewa

2015-01-01

The aim of the work was the analysis of personality traits of men serving a custodial sentence for driving under the influence of alcohol. The study included 44 males serving a custodial sentence for drink driving, 45 males serving a custodial sentence for assault and robbery as well as 32 men with no criminal record, who had never driven a motor vehicle under the influence of alcohol. The following research methods were used during the study: the Socio-demographic Questionnaire designed by the authors, the KRS, the Cattell's IPAT, the NI, the ACL and the Life style Questionnaire. The obtained results indicate significant statistical differences between the men serving the custodial sentence for drink driving as regards stress coping, anxiety level, intensified need to look for new experiences as well as anti-social personality traits. The men serving a custodial sentence for drink driving show intensified traits of antisocial personality, higher level of anxiety, intensified impulsiveness irritability, distrust, aggression, egocentrism, eccentricity, intensified need for recognition, breaking social standards, experiencing various stimuli, new impressions, greater adaptation difficulties, less self-discipline, lower self-esteem as well as more frequently used destructive, escapist and emotional stress coping strategies as compared to the people with no criminal record, who never drove while under the influence of alcohol. As regards the intensity of personality disorders, stress coping strategies and self-image no significant differences were found between the men serving a custodial sentence for drink driving and those imprisoned for assault and robbery.

Electric Vehicle - Economical driving

DEFF Research Database (Denmark)

Jensen, VCE, Steen V.; Schøn, Henriette

1999-01-01

Instruct the reader in getting most satisfaction out of an EV, especially concerning driving and loading.......Instruct the reader in getting most satisfaction out of an EV, especially concerning driving and loading....

CLIC Drive Beam Phase Stabilisation

CERN Document Server

Gerbershagen, Alexander; Schulte, Daniel

The thesis presents phase stability studies for the Compact Linear Collider (CLIC) and focuses in particular on CLIC Drive Beam longitudinal phase stabilisation. This topic constitutes one of the main feasibility challenges for CLIC construction and is an essential component of the current CLIC stabilisation campaign. The studies are divided into two large interrelated sections: the simulation studies for the CLIC Drive Beam stability, and measurements, data analysis and simulations of the CLIC Test Facility (CTF3) Drive Beam phase errors. A dedicated software tool has been developed for a step-by-step analysis of the error propagation through the CLIC Drive Beam. It uses realistic RF potential and beam loading amplitude functions for the Drive and Main Beam accelerating structures, complete models of the recombination scheme and compressor chicane as well as of further CLIC Drive Beam modules. The tool has been tested extensively and its functionality has been verified. The phase error propagation at CLIC h...

Two-Phase Induction Motor Drives

Directory of Open Access Journals (Sweden)

Gholam Reza Arab Markadeh

2010-10-01

Full Text Available The lack of variable-speed drives for two (single induction motor is a reality. This article attempts mainly to investigate the reasons for this lack of variable – speed drives. This paper deals with literature survey of various existing converter topologies, which have been proposed for adjustable speed single phase induction motor drives. Various converter topologies have been compared in this paper. Among these converter topologies, the adjustable frequency PWM inverter is the best choice for single-phase induction motor drives. However, adjustable-frequency drives have not been widely used with single-phase Induction motors. The open-loop constant V/F control law cannot be used with the single-phase induction motor drives as it is used with three phase motors. The variation of the operating frequency at lower speed range with constant load torque causes variation in motor's slip. A constant V/F control is suitable only over the upper speed range.

Harmonic analysis and FPGA implementation of SHE controlled three phase CHB 11-level inverter in MV drives using deterministic and stochastic optimization techniques.

Science.gov (United States)

Vesapogu, Joshi Manohar; Peddakotla, Sujatha; Kuppa, Seetha Rama Anjaneyulu

2013-01-01

With the advancements in semiconductor technology, high power medium voltage (MV) Drives are extensively used in numerous industrial applications. Challenging technical requirements of MV Drives is to control multilevel inverter (MLI) with less Total harmonic distortion (%THD) which satisfies IEEE standard 519-1992 harmonic guidelines and less switching losses. Among all modulation control strategies for MLI, Selective harmonic elimination (SHE) technique is one of the traditionally preferred modulation control technique at fundamental switching frequency with better harmonic profile. On the other hand, the equations which are formed by SHE technique are highly non-linear in nature, may exist multiple, single or even no solution at particular modulation index (MI). However, in some MV Drive applications, it is required to operate over a range of MI. Providing analytical solutions for SHE equations during the whole range of MI from 0 to 1, has been a challenging task for researchers. In this paper, an attempt is made to solve SHE equations by using deterministic and stochastic optimization methods and comparative harmonic analysis has been carried out. An effective algorithm which minimizes %THD with less computational effort among all optimization algorithms has been presented. To validate the effectiveness of proposed MPSO technique, an experiment is carried out on a low power proto type of three phase CHB 11- level Inverter using FPGA based Xilinx's Spartan -3A DSP Controller. The experimental results proved that MPSO technique has successfully solved SHE equations over all range of MI from 0 to 1, the %THD obtained over major range of MI also satisfies IEEE 519-1992 harmonic guidelines too.

Driving behaviour in adults with attention deficit/hyperactivity disorder.

Science.gov (United States)

Groom, Madeleine J; van Loon, Editha; Daley, David; Chapman, Peter; Hollis, Chris

2015-07-28

Little is known about the impact of cognitive impairments on driving in adults with ADHD. The present study compared the performance of adults with and without ADHD in a driving simulator on two different routes: an urban route which we hypothesised would exacerbate weak impulse control in ADHD and a motorway route, to challenge deficits in sustained attention. Adults with (n = 22, 16 males) and without (n = 21, 18 males) ADHD completed a simulated driving session while eye movement data were recorded simultaneously. Participants also completed the Manchester Driving Behaviour Questionnaire (DBQ) and the Conners Adult ADHD Rating Scale (CAARS). Measures of driving performance included average speed, proportion distance travelled over speed limit (speeding) and lane deviation. These variables and the eye movement measures (spread of fixations, mean fixation duration) were compared between groups and routes. Also, driving behaviours, including responses to programmed events, were categorised and the frequencies within categories were compared between groups. Finally, speech analysis was performed to compare emotional verbal expressions during driving between groups. ADHD participants reported significantly more Violations and Lapses on the DBQ than control participants and significantly more accidents. Average speed and speeding were also higher but did not interact with route type. ADHD participants showed poorer vehicle control, greater levels of frustration with other road users (including greater frequencies of negative comments) and a trend for less safe driving when changing lanes/overtaking on the motorway. These effects were predicted by hyperactive/impulsive CAARS scores. They were also more likely to cause a crash/near miss when an event occurred on the urban route. The results suggest that difficulty regulating and controlling impulsive behavior, reflected in speeding, frustration with other road users, less safety when changing lanes on the

[Driving and health at work].

Science.gov (United States)

Giorgio, Marie-Thérèse

2015-09-01

The role of the occupational physician is to prevent occupational accidents and diseases. Therefore, he is the one to decide if a worker is fit to drive in the context of his professional activity, including in cases where no specific driving license is required (e.g. forklift truck, mobile crane). This decision is an important one, as two thirds of fatal occupational accidents occur on the road. The decision is made on the basis of both a medical examination and the regulation, which indicates all contraindications to driving. The physician's responsibility is involved, as is the employer's, as he must ensure that his employee is fit to drive and possesses a valid driving license at all times. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Creating a driving profile for older adults using GPS devices and naturalistic driving methodology [version 2; referees: 2 approved, 1 approved with reservations

Directory of Open Access Journals (Sweden)

Ganesh M. Babulal

2016-12-01

Full Text Available Background/Objectives: Road tests and driving simulators are most commonly used in research studies and clinical evaluations of older drivers. Our objective was to describe the process and associated challenges in adapting an existing, commercial, off-the-shelf (COTS, in-vehicle device for naturalistic, longitudinal research to better understand daily driving behavior in older drivers. Design: The Azuga G2 Tracking DeviceTM was installed in each participant’s vehicle, and we collected data over 5 months (speed, latitude/longitude every 30-seconds when the vehicle was driven.  Setting: The Knight Alzheimer’s Disease Research Center at Washington University School of Medicine. Participants: Five individuals enrolled in a larger, longitudinal study assessing preclinical Alzheimer disease and driving performance.  Participants were aged 65+ years and had normal cognition. Measurements:  Spatial components included Primary Location(s, Driving Areas, Mean Centers and Unique Destinations.  Temporal components included number of trips taken during different times of the day.  Behavioral components included number of hard braking, speeding and sudden acceleration events. Methods:  Individual 30-second observations, each comprising one breadcrumb, and trip-level data were collected and analyzed in R and ArcGIS.  Results: Primary locations were confirmed to be 100% accurate when compared to known addresses.  Based on the locations of the breadcrumbs, we were able to successfully identify frequently visited locations and general travel patterns.  Based on the reported time from the breadcrumbs, we could assess number of trips driven in daylight vs. night.  Data on additional events while driving allowed us to compute the number of adverse driving alerts over the course of the 5-month period. Conclusions: Compared to cameras and highly instrumented vehicle in other naturalistic studies, the compact COTS device was quickly installed and

Comparative analyses reveal high levels of conserved colinearity between the finger millet and rice genomes.

Science.gov (United States)

Srinivasachary; Dida, Mathews M; Gale, Mike D; Devos, Katrien M

2007-08-01

Finger millet is an allotetraploid (2n = 4x = 36) grass that belongs to the Chloridoideae subfamily. A comparative analysis has been carried out to determine the relationship of the finger millet genome with that of rice. Six of the nine finger millet homoeologous groups corresponded to a single rice chromosome each. Each of the remaining three finger millet groups were orthologous to two rice chromosomes, and in all the three cases one rice chromosome was inserted into the centromeric region of a second rice chromosome to give the finger millet chromosomal configuration. All observed rearrangements were, among the grasses, unique to finger millet and, possibly, the Chloridoideae subfamily. Gene orders between rice and finger millet were highly conserved, with rearrangements being limited largely to single marker transpositions and small putative inversions encompassing at most three markers. Only some 10% of markers mapped to non-syntenic positions in rice and finger millet and the majority of these were located in the distal 14% of chromosome arms, supporting a possible correlation between recombination and sequence evolution as has previously been observed in wheat. A comparison of the organization of finger millet, Panicoideae and Pooideae genomes relative to rice allowed us to infer putative ancestral chromosome configurations in the grasses.

Driving intoxicated: is hospital admission protective against legal ramifications?

Science.gov (United States)

Cheek, Susannah Mary; Murry, Jason Steven; Truitt, Michael Seth; Dunn, Ernest Lewis

2013-12-01

According to the US National Highway Traffic Safety Administration, in 2010, 10,228 people were killed in alcohol-impaired driving crashes. Daily, intoxicated drivers are seen in trauma centers across the country. At our trauma center, we sought to determine the number of drivers who had a documented elevation in their blood alcohol content (BAC) and compare this with county police records to evaluate how many charges for driving while intoxicated (DWI) were issued. A retrospective chart review was performed for trauma admissions during a 3-year period. Patients with a BAC of less than 0.08 g/dL were excluded. Only documented drivers were included. This group of intoxicated drivers was then compared against public records from the Dallas County for any record of a charge of DWI. During a 3-year period, from 2009 to 2011, 118 drivers had a confirmed BAC above the legal limit of 0.08 g/dL. Average BAC level was 0.218 g/dL. Injuries varied widely between patients with an average Injury Severity Score (ISS) of 11. Extremity fractures were seen in 27%, facial fractures were seen in 16%, and intracranial hemorrhage was seen in 7%. Forty-eight percent of the patients were admitted to the intensive care unit initially, with an average length of intensive care unit stay of 1.5 days (range, 0-25 days). Only 18% of our patients (21) received a charge of DWI. Four patients were charge with related offenses. A motor vehicle accident may be protective against the legal ramifications of drinking and driving. Less than 20% of patients who were driving under the influence incurred any legal repercussion. Deterrents that prevent law enforcement from being able to obtain evidence needed for prosecution should be eliminated. Health care providers and law enforcement agencies should work as a team to help mitigate the incidence of drunk driving and its burden on society. Epidemiologic study, level III.

Longitudinal study of self-imposed driving restrictions and deficit awareness in patients with Alzheimer disease.

Science.gov (United States)

Cotrell, V; Wild, K

1999-01-01

Thirty-five patients with Alzheimer disease (AD), including 19 who were still driving, were evaluated for level of awareness and driving status. There was no significant correlation between driving status and Mini-Mental State Examination (MMSE) scores. Only the attention subscore of the awareness questionnaire yielded a statistically significant difference between drivers and nondrivers. Follow-up of the patients who were still driving was conducted 12-18 months later. All but 4 patients had stopped driving. Caregivers responded to a questionnaire assessing the patient's driving behaviors since the onset of AD. There was no correlation between MMSE and driving status. In 7 of 10 cases, caregivers or patients made the decision that the patient should stop driving. However, caregivers reported long periods between the caregiver's perception that the patient should stop driving and actual cessation (0.5-48 months). Results suggest that AD patients do restrict several areas of their driving voluntarily and that a failure to do so may be associated with an awareness deficit. In particular, a deficit of awareness for attention was significantly associated with an absence of restricted driving behaviors such as avoiding unfamiliar routes. Awareness of a deficit that is related to driving performance may be critical to restricted driving behavior, and this change in behavior may enable the patient to prolong his or her status as a driver.

[Drunk driving in professional drivers in the Vía Blanca highway in Cuba].

Science.gov (United States)

Guanche Garcell, Humberto; Suárez Enríquez, Tomás; Gutiérrez García, Francisco; Martínez Quesada, Carlos; Mendoza Pérez, Ramón

2006-01-01

To determine the frequency of drunk driving in professional drivers (Via Blanca, Havana City), we carried out a descriptive study of 832 drivers selected by multistage stratified sampling. A structured interview with each driver was carried out to record the variables under study, and a breath alcohol test was subsequently performed. The frequency of drunk driving was 8.18% (95% CI, 5.94%-10.42%), with a predominance of drivers with alcohol levelsDrunk driving was more frequent in "high risk" hours, in drivers aged between 40 and 49 years old (10.3%), and in those with 15 to 24 years of experience (11.02%). The frequency of drunk driving found in this study highlights the need to design traffic accident prevention strategies.

Naturalistic driving observations of manual and visual-manual interactions with navigation systems and mobile phones while driving.

NARCIS (Netherlands)

Christoph, M. Nes, N. van & Knapper, A.

2014-01-01

This paper discusses a naturalistic driving study on the use of mobile phones and navigation systems while driving. Manual interactions with these devices while driving can cause distraction from the driving task and reduce traffic safety. In this study 21 subjects were observed for 5 weeks. Their

Piezoelectric drive circuit

Science.gov (United States)

Treu, C.A. Jr.

1999-08-31

A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes. 7 figs.

Commercial Truck Driver Health and Safety: Exploring Distracted Driving Performance and Self-Reported Driving Skill.

Science.gov (United States)

Stavrinos, Despina; Heaton, Karen; Welburn, Sharon C; McManus, Benjamin; Griffin, Russell; Fine, Philip R

2016-08-01

Reducing distracters detrimental to commercial truck driving is a critical component of improving the safety performance of commercial drivers, and makes the highways safer for all drivers. This study used a driving simulator to examine effects of cell phone, texting, and email distractions as well as self-reported driver optimism bias on the driving performance of commercial truck drivers. Results revealed that more visually demanding tasks were related to poorer driving performance. However, the cell phone task resulted in less off-the-road eye glances. Drivers reporting being "very skilled" displayed poorer driving performance than those reporting being "skilled." Onboard communication devices provide a practical, yet visually and manually demanding, solution for connecting drivers and dispatchers. Trucking company policies should minimize interaction between dispatchers and drivers when the truck is in motion. Training facilities should integrate driving simulators into the instruction of commercial drivers, targeting over-confident drivers. © 2016 The Author(s).

Reconstruction of the drive underlying food intake and its control by leptin and dieting

NARCIS (Netherlands)

Grasman, J.

2013-01-01

The intake of food and the expenditure of calories is modelled by a system of differential equations. The state variables are the amount of calories stored in adipose tissue and the level of plasma leptin. The model has as input a drive that controls the intake of food. This drive consists of a

Suitability of Synthetic Driving Profiles from Traffic Micro-Simulation for Real-World Energy Analysis: Preprint

Energy Technology Data Exchange (ETDEWEB)

Hou, Yunfei; Wood, Eric; Burton, Evan; Gonder, Jeffrey

2015-10-14

A shift towards increased levels of driving automation is generally expected to result in improved safety and traffic congestion outcomes. However, little empirical data exists to estimate the impact that automated driving could have on energy consumption and greenhouse gas emissions. In the absence of empirical data on differences between drive cycles from present day vehicles (primarily operated by humans) and future vehicles (partially or fully operated by computers) one approach is to model both situations over identical traffic conditions. Such an exercise requires traffic micro-simulation to not only accurately model vehicle operation under high levels of automation, but also (and potentially more challenging) vehicle operation under present day human drivers. This work seeks to quantify the ability of a commercial traffic micro-simulation program to accurately model real-world drive cycles in vehicles operated primarily by humans in terms of driving speed, acceleration, and simulated fuel economy. Synthetic profiles from models of freeway and arterial facilities near Atlanta, Georgia, are compared to empirical data collected from real-world drivers on the same facilities. Empirical and synthetic drive cycles are then simulated in a powertrain efficiency model to enable comparison on the basis of fuel economy. Synthetic profiles from traffic micro-simulation were found to exhibit low levels of transient behavior relative to the empirical data. Even with these differences, the synthetic and empirical data in this study agree well in terms of driving speed and simulated fuel economy. The differences in transient behavior between simulated and empirical data suggest that larger stochastic contributions in traffic micro-simulation (relative to those present in the traffic micro-simulation tool used in this study) are required to fully capture the arbitrary elements of human driving. Interestingly, the lack of stochastic contributions from models of human drivers

Superconducting cavity driving with FPGA controller

International Nuclear Information System (INIS)

Czarski, Tomasz; Koprek, Waldemar; Pozniak, Krzysztof T.; Romaniuk, Ryszard S.; Simrock, Stefan; Brandt, Alexander; Chase, Brian; Carcagno, Ruben; Cancelo, Gustavo; Koeth, Timothy W.

2006-01-01

A digital control of superconducting cavities for a linear accelerator is presented. FPGA-based controller, supported by Matlab system, was applied. Electrical model of a resonator was used for design of a control system. Calibration of the signal path is considered. Identification of cavity parameters has been carried out for adaptive control algorithm. Feed-forward and feedback modes were applied in operating the cavities. Required performance has been achieved; i.e. driving on resonance during filling and field stabilization during flattop time, while keeping reasonable level of the power consumption. Representative results of the experiments are presented for different levels of the cavity field gradient

Predictive validity of driving-simulator assessments following traumatic brain injury: a preliminary study.

Science.gov (United States)

Lew, Henry L; Poole, John H; Lee, Eun Ha; Jaffe, David L; Huang, Hsiu-Chen; Brodd, Edward

2005-03-01

To evaluate whether driving simulator and road test evaluations can predict long-term driving performance, we conducted a prospective study on 11 patients with moderate to severe traumatic brain injury. Sixteen healthy subjects were also tested to provide normative values on the simulator at baseline. At their initial evaluation (time-1), subjects' driving skills were measured during a 30-minute simulator trial using an automated 12-measure Simulator Performance Index (SPI), while a trained observer also rated their performance using a Driving Performance Inventory (DPI). In addition, patients were evaluated on the road by a certified driving evaluator. Ten months later (time-2), family members observed patients driving for at least 3 hours over 4 weeks and rated their driving performance using the DPI. At time-1, patients were significantly impaired on automated SPI measures of driving skill, including: speed and steering control, accidents, and vigilance to a divided-attention task. These simulator indices significantly predicted the following aspects of observed driving performance at time-2: handling of automobile controls, regulation of vehicle speed and direction, higher-order judgment and self-control, as well as a trend-level association with car accidents. Automated measures of simulator skill (SPI) were more sensitive and accurate than observational measures of simulator skill (DPI) in predicting actual driving performance. To our surprise, the road test results at time-1 showed no significant relation to driving performance at time-2. Simulator-based assessment of patients with brain injuries can provide ecologically valid measures that, in some cases, may be more sensitive than a traditional road test as predictors of long-term driving performance in the community.

Fast wave current drive

International Nuclear Information System (INIS)

Goree, J.; Ono, M.; Colestock, P.; Horton, R.; McNeill, D.; Park, H.

1985-07-01

Fast wave current drive is demonstrated in the Princeton ACT-I toroidal device. The fast Alfven wave, in the range of high ion-cyclotron harmonics, produced 40 A of current from 1 kW of rf power coupled into the plasma by fast wave loop antenna. This wave excites a steady current by damping on the energetic tail of the electron distribution function in the same way as lower-hybrid current drive, except that fast wave current drive is appropriate for higher plasma densities

Neuromorphic meets neuromechanics, part II: the role of fusimotor drive

Science.gov (United States)

Jalaleddini, Kian; Minos Niu, Chuanxin; Chakravarthi Raja, Suraj; Sohn, Won Joon; Loeb, Gerald E.; Sanger, Terence D.; Valero-Cuevas, Francisco J.

2017-04-01

Objective. We studied the fundamentals of muscle afferentation by building a Neuro-mechano-morphic system actuating a cadaveric finger. This system is a faithful implementation of the stretch reflex circuitry. It allowed the systematic exploration of the effects of different fusimotor drives to the muscle spindle on the closed-loop stretch reflex response. Approach. As in Part I of this work, sensory neurons conveyed proprioceptive information from muscle spindles (with static and dynamic fusimotor drive) to populations of α-motor neurons (with recruitment and rate coding properties). The motor commands were transformed into tendon forces by a Hill-type muscle model (with activation-contraction dynamics) via brushless DC motors. Two independent afferented muscles emulated the forces of flexor digitorum profundus and the extensor indicis proprius muscles, forming an antagonist pair at the metacarpophalangeal joint of a cadaveric index finger. We measured the physical response to repetitions of bi-directional ramp-and-hold rotational perturbations for 81 combinations of static and dynamic fusimotor drives, across four ramp velocities, and three levels of constant cortical drive to the α-motor neuron pool. Main results. We found that this system produced responses compatible with the physiological literature. Fusimotor and cortical drives had nonlinear effects on the reflex forces. In particular, only cortical drive affected the sensitivity of reflex forces to static fusimotor drive. In contrast, both static fusimotor and cortical drives reduced the sensitivity to dynamic fusimotor drive. Interestingly, realistic signal-dependent motor noise emerged naturally in our system without having been explicitly modeled. Significance. We demonstrate that these fundamental features of spinal afferentation sufficed to produce muscle function. As such, our Neuro-mechano-morphic system is a viable platform to study the spinal mechanisms for healthy muscle function—and its

Relationship of impaired-driving enforcement intensity to drinking and driving on the roads.

Science.gov (United States)

Fell, James C; Waehrer, Geetha; Voas, Robert B; Auld-Owens, Amy; Carr, Katherine; Pell, Karen

2015-01-01

It is principally the area of enforcement that offers the greatest opportunity for reducing alcohol-impaired driving in the near future. How much of a reduction in drinking and driving would be achieved by how much improvement in enforcement intensity? We developed logistic regression models to explore how enforcement intensity (6 different measures) related to the prevalence of weekend nighttime drivers in the 2007 National Roadside Survey who had been drinking (blood alcohol concentration [BAC] ≥ 0.00 g/dl), who had BACs ≥ 0.05 g/dl, and who were driving with an illegal BAC ≥ 0.08 g/dl. Drivers on the roads in our sample of 30 communities who were exposed to fewer than 228 traffic stops per 10,000 population aged 18 and older had 2.4 times the odds of being BAC positive, 3.6 times the odds of driving with a BAC ≥ 0.05, and 3.8 times the odds of driving with a BAC ≥ 0.08 compared to those drivers on the roads in communities with more than 1,275 traffic stops per 10,000 population. Drivers on the roads in communities with fewer than 3.7 driving under the influence (DUI) arrests per 10,000 population had 2.7 times the odds of BAC-positive drivers on the roads compared to communities with the highest intensity of DUI arrest activity (>38 DUI arrests per 10,000 population). The number of traffic stops and DUI arrests per capita were significantly associated with the odds of drinking and driving on the roads in these communities. This might reflect traffic enforcement visibility. The findings in this study may help law enforcement agencies around the country adjust their traffic enforcement intensity to reduce impaired driving in their community. Copyright © 2014 by the Research Society on Alcoholism.

Method for driving an actuator, actuator drive, and apparatus comprising an actuator

NARCIS (Netherlands)

2010-01-01

An actuator driver circuit includes a drive signal source and an electrical damping element having a negative resistance connected in series with the drive signal source. A controllable switch is provided for selectively switching the electrical damping element into or put of a signal path from a

Comparing a driving simulator to the real road regarding distracted driving speed

NARCIS (Netherlands)

Knapper, Allert; Christoph, Michiel; Hagenzieker, Marjan; Brookhuis, Karel

2015-01-01

Relative and absolute validity of a driving simulator were assessed regarding effects on mean speed and speed variation during distracting secondary tasks, and normal driving. 16 participants drove the same route four times, twice in a simulator and twice in the real world. They performed way

Comparing a driving simulator to the real road regarding distracted driving speed.

NARCIS (Netherlands)

Knapper, A. Christoph, M. Hagenzieker, M. & Brookhuis, K.

2015-01-01

Relative and absolute validity of a driving simulator were assessed regarding effects on mean speed and speed variation during distracting secondary tasks, and normal driving. 16 participants drove the same route four times, twice in a simulator and twice in the real world. They performed way

A positive view on road safety: Can 'car karma' contribute to safe driving styles?

Science.gov (United States)

Kleisen, Lucienne M B

2013-01-01

Many studies in the field of road safety are occupied with studying road unsafety since it generally concentrates on traffic crashes, crash, risk, and aberrant driving behaviour, especially in relation to young drivers. However, this study shows there is scope for thinking about driving and driver training from a different vantage point, that is in terms of safe or normal driving. The findings are reported from four group interviews with young drivers (18-25 years of age); the young drivers discussed their ideas of safe driving and their reasons for using (or not using) safe driving styles. The data show a type of optimistic thinking among young drivers which they call 'car karma'. This finding offers an opportunity to reconceptualise driving in a way that is focused on normal, safe driving styles, a topic that has received less attention in the past. The paper argues that greater focus on safe driving styles could be more conducive to young drivers actually driving safely than focusing on, for instance, crashes, which on an individual level are relatively rare (Elander et al., 1993, p. 277). Based on empirical research, the first positively stated definition of road safety is proposed based on the notion of 'car karma'. Copyright © 2012 Elsevier Ltd. All rights reserved.

Multi-Motor Drives for Crane Application

Directory of Open Access Journals (Sweden)

MITROVIC, N.

2009-10-01

Full Text Available This paper focuses on the application of adjustable speed induction motor drives for gantry cranes. Modern solution considers application of frequency converters for all drives. Multi-motor drives are standard solutions in crane application and requirements of load sharing are present. Presented algorithm provides load sharing proportional to the rated motor power on the simple and practically applicable method on the basis of estimated torques by frequency converters, and controller realized in PLC. Special attention is devoted to wide span gantry drive and algorithm for skew elimination. Solutions for load distribution in multi-motor drive, as well as mode of gantry drive skew elimination, are described. Suggested solution concept is confirmed by the experimental results.

Driving Force Filtering and Driving Mechanism Analysis of Urban Agricultural Development in Weifang County, China

Directory of Open Access Journals (Sweden)

SUI Fei-fei

2016-03-01

Full Text Available As an agricultural nation, the agricultural landscape is the basic appearance and existence in China, but the common existence often be neglected and contempted. As a new type of design and ideology, the development of urban agricultural landscape will greatly affect the texture and structure of the urban space. According to the urban agricultural production data and the socio-economic data of Weifang County, a set of evaluation index system that could analyze quantitatively the driving force of urban agricultural production changes and the internal drive mechanism was built. The original driving force indicators of economy, society, resources and environment from the time-series were chosen, and then 15 driving forces from the original driving forces by correlation analysis and principal component analysis were selected. The degree of influence was analyzed and the driving forces model by means of partial least squares(PLS was built. The results demonstrated that the factors greatly influenced the increase of urban agricultural output value in Weifang County were per capita net income of rural residents, agricultural machinery total power, effective irrigation area, centralized treatment rate of urban sewage, with the driving exponents 0.2509, 0.1019, 0.1655, 0.1332, respectively. The negative influence factor was the use amount of agricultural plastic film and the driving exponent was-0.2146. The research provides a reference for the development of urban agriculture, as well as a reference for the related study.

ECO-DRIVING MODELING ENVIRONMENT

Science.gov (United States)

2015-11-01

This research project aims to examine the eco-driving modeling capabilities of different traffic modeling tools available and to develop a driver-simulator-based eco-driving modeling tool to evaluate driver behavior and to reliably estimate or measur...

Driving and Age-Related Macular Degeneration

OpenAIRE

Owsley, Cynthia; McGwin, Gerald

2008-01-01

This article reviews the research literature on driving and age-related macular degeneration, which is motivated by the link between driving and the quality of life of older adults and their increased collision rate. It addresses the risk of crashes, driving performance, driving difficulty, self-regulation, and interventions to enhance, safety, and considers directions for future research.

Risky driving and lifestyles in adolescence.

Science.gov (United States)

Bina, Manuela; Graziano, Federica; Bonino, Silvia

2006-05-01

Several studies have shown that risky driving is especially prevalent among young drivers and recent research has pointed out that driving in adolescence should be investigated in the more general context of adolescent development. The first aim of this contribution was to analyze involvement in risky driving in a normative sample of 645 Italian adolescents, boys and girls, aged 14-17, through a self-report questionnaire. A second aim was to evaluate the association between risky driving and lifestyle, defined as involvement in other health risk behaviors and leisure activities. The main results showed that many adolescents drove cars and motorcycles without the required driving license and the most frequent offences were speeding and failure to maintain a safe braking distance. Gender and age differences were also investigated. Results concerning the association between risky driving and lifestyle showed that risky driving was not an isolated behavior. Boys who displayed risky driving practices were more likely to adopt a lifestyle characterized by high involvement in antisocial behaviors, tobacco smoking, comfort eating and time spent in non-organized activities with friends. Girls involved in risky driving were more likely to be involved in other risk-taking behaviors, antisocial behaviors and drug use.

Drive for thinness, affect regulation and physical activity in eating disorders: a daily life study.

Science.gov (United States)

Vansteelandt, Kristof; Rijmen, Frank; Pieters, Guido; Probst, Michel; Vanderlinden, Johan

2007-08-01

Using Ecological Momentary Assessment, the within patient associations between drive for thinness, emotional states, momentary urge to be physically active and physical activity were studied in 32 inpatients with an eating disorder. Participants received an electronic device and had to indicate at nine random times a day during 1 week their momentary drive for thinness, positive and negative emotional states and their urge to be physically active and physical activity. Multilevel analyses indicated that patients with higher mean levels for urge to be physically active were characterized by lower body mass index (BMI) and chronically negative affect whereas patients with higher mean levels for physical activity were characterized by lower BMI and higher dispositions for drive for thinness. In addition, within patient relations between drive for thinness and urge to be physically active were moderated by BMI and chronically negative affect whereas within patient relations between drive for thinness and physical activity were moderated by BMI. Finally, also positive emotional states were significantly associated with physical activity within patients. By using a daily process design, characteristics of physical activity were revealed that have not been identified with assessment methods that have a lower time resolution.

Driving, brain injury and assistive technology.

Science.gov (United States)

Lane, Amy K; Benoit, Dana

2011-01-01

Individuals with brain injury often present with cognitive, physical and emotional impairments which impact their ability to resume independence in activities of daily living. Of those activities, the resumption of driving privileges is cited as one of the greatest concerns by survivors of brain injury. The integration of driving fundamentals within the hierarchical model proposed by Keskinen represents the complexity of skills and behaviors necessary for driving. This paper provides a brief review of specific considerations concerning the driver with TBI and highlights current vehicle technology which has been developed by the automotive industry and by manufacturers of adaptive driving equipment that may facilitate the driving task. Adaptive equipment technology allows for compensation of a variety of operational deficits, whereas technological advances within the automotive industry provide drivers with improved safety and information systems. However, research has not yet supported the use of such intelligent transportation systems or advanced driving systems for drivers with brain injury. Although technologies are intended to improve the safety of drivers within the general population, the potential of negative consequences for drivers with brain injury must be considered. Ultimately, a comprehensive driving evaluation and training by a driving rehabilitation specialist is recommended for individuals with brain injury. An understanding of the potential impact of TBI on driving-related skills and knowledge of current adaptive equipment and technology is imperative to determine whether return-to-driving is a realistic and achievable goal for the individual with TBI.

Lower hybrid heating and current drive in ignitor shear reversal scenarios

Energy Technology Data Exchange (ETDEWEB)

Barbato, E; Pinaccione, L [Italian Agengy for New Technologies, Energy and the Environment, Centro Ricerche Frascati, Rome (Italy). Dip. Energia

1996-05-01

Injection of Lower Hybrid (LH) Wave power at 8 GHz is considered into IGNITOR shear reversal scenarios, characterized by a reduced plasma current and density. Power deposition calculation are performed to establish whether LH waves can be used both as central heating and off axis current drive tool. It turns out that LH waves can be used (a) for central plasma heating purpose during the current vamp phase, to freeze the shear reversed configuration, at the power level of {approx}10 MW. (b) to drive a current in the outer part of the plasma at the power level of 20 MW. In this way around 1/3-1/6 of the total current in the proper plasma position (i.e. where q is minimum) is driven.

Decoupling control of steering and driving system for in-wheel-motor-drive electric vehicle

Science.gov (United States)

Zhang, Han; Zhao, Wanzhong

2018-02-01

To improve the maneuverability and stability of in-wheel-motor-drive electric vehicle, a control strategy based on nonlinear decoupling control method is proposed in this paper, realizing the coordinated control of the steering and driving system. At first, the nonlinear models of the in-wheel-motor-drive electric vehicle and its sub-system are constructed. Then the inverse system decoupling theory is applied to decompose the nonlinear system into several independent subsystems, which makes it possible to realize the coordinated control of each subsystem. Next, the μ-Synthesis theory is applied to eliminate the influence of model uncertainty, improving the stability, robustness and tracking performance of in-wheel-motor-drive electric vehicle. Simulation and experiment results and numerical analyses, based on the electric vehicle actuated by in-wheel-motors, prove that the proposed control method is effective to accomplish the decoupling control of the steering and driving system in both simulation and real practice.

Visually impaired drivers who use bioptic telescopes: self-assessed driving skills and agreement with on-road driving evaluation.

Science.gov (United States)

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

2014-01-15

To compare self-assessed driving habits and skills of licensed drivers with central visual loss who use bioptic telescopes to those of age-matched normally sighted drivers, and to examine the association between bioptic drivers' impressions of the quality of their driving and ratings by a "backseat" evaluator. Participants were licensed bioptic drivers (n = 23) and age-matched normally sighted drivers (n = 23). A questionnaire was administered addressing driving difficulty, space, quality, exposure, and, for bioptic drivers, whether the telescope was helpful in on-road situations. Visual acuity and contrast sensitivity were assessed. Information on ocular diagnosis, telescope characteristics, and bioptic driving experience was collected from the medical record or in interview. On-road driving performance in regular traffic conditions was rated independently by two evaluators. Like normally sighted drivers, bioptic drivers reported no or little difficulty in many driving situations (e.g., left turns, rush hour), but reported more difficulty under poor visibility conditions and in unfamiliar areas (P Driving exposure was reduced in bioptic drivers (driving 250 miles per week on average vs. 410 miles per week for normally sighted drivers, P = 0.02), but driving space was similar to that of normally sighted drivers (P = 0.29). All but one bioptic driver used the telescope in at least one driving task, and 56% used the telescope in three or more tasks. Bioptic drivers' judgments about the quality of their driving were very similar to backseat evaluators' ratings. Bioptic drivers show insight into the overall quality of their driving and areas in which they experience driving difficulty. They report using the bioptic telescope while driving, contrary to previous claims that it is primarily used to pass the vision screening test at licensure.

Neuropsychological assessment of driving ability and self-evaluation: a comparison between driving offenders and a control group.

Science.gov (United States)

Zingg, Christina; Puelschen, Dietrich; Soyka, Michael

2009-12-01

The relationship between performance in neuropsychological tests and actual driving performance is unclear and results of studies on this topic differ. This makes it difficult to use neuropsychological tests to assess driving ability. The ability to compensate cognitive deficits plays a crucial role in this context. We compared neuropsychological test results and self-evaluation ratings between three groups: driving offenders with a psychiatric diagnosis relevant for driving ability (mainly alcohol dependence), driving offenders without such a diagnosis and a control group of non-offending drivers. Subjects were divided into two age categories (19-39 and 40-66 years). It was assumed that drivers with a psychiatric diagnosis relevant for driving ability and younger driving offenders without a psychiatric diagnosis would be less able to adequately assess their own capabilities than the control group. The driving offenders with a psychiatric diagnosis showed poorer concentration, reactivity, cognitive flexibility and problem solving, and tended to overassess their abilities in intelligence and attentional functions, compared to the other two groups. Conversely, younger drivers rather underassessed their performance.

Polar-Drive Experiments at the National Ignition Facility

Science.gov (United States)

Hohenberger, M.

2014-10-01

To support direct-drive inertial confinement fusion (ICF) experiments at the National Ignition Facility (NIF) in its indirect-drive beam configuration, the polar-drive (PD) concept has been proposed. It requires direct-drive-specific beam smoothing, phase plates, and repointing the NIF beams toward the equator to ensure symmetric target irradiation. First experiments testing the performance of ignition-relevant PD implosions at the NIF have been performed. The goal of these early experiments was to develop a stable, warm implosion platform to investigate laser deposition and laser-plasma instabilities at ignition-relevant plasma conditions, and to develop and validate ignition-relevant models of laser deposition and heat conduction. These experiments utilize the NIF in its current configuration, including beam geometry, phase plates, and beam smoothing. Warm, 2.2-mm-diam plastic shells were imploded with total drive energies ranging from ~ 350 to 750 kJ with peak powers of 60 to 180 TW and peak on-target intensities from 4 ×1014 to 1 . 2 ×1015 W/cm2. Results from these initial experiments are presented, including the level of hot-electron preheat, and implosion symmetry and shell trajectory inferred via self-emission imaging and backlighting. Experiments are simulated with the 2-D hydrodynamics code DRACO including a full 3-D ray trace to model oblique beams, and a model for cross-beam energy transfer (CBET). These simulations indicate that CBET affects the shell symmetry and leads to a loss of energy imparted onto the shell, consistent with the experimental data. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

Drunk driving among novice drivers, possible prevention with additional psychological module in driving school curriculum.

Science.gov (United States)

Eensoo, Diva; Paaver, Marika; Harro, Jaanus

2011-01-01

Road traffic collisions caused by drunk driving pose a significant public health problem all over the world. Therefore additional preventive activities against drunk driving should be worked out. The aim of the study was to assess drunk driving in novice drivers after a psychological intervention taking into account also impulsivity, law obedience, and alcohol-related measures. An intervention study was started with 1889 car driver's license attempters during their driving school studies. Subjects were classified as intervention group (n=1083, mean age 23.1 (SD=7.4) years), control group (n=517, mean age 22.8 (SD=7.1) years) and "lost" group (n=289, mean age 23.0 (SD=6.9) years). "Lost" group subjects had been assigned into the intervention group, but they did not participate in the intervention. Subjects of the intervention group participated in a psychological intervention on the dangers of impulsive behavior in traffic. After a three year follow-up period it appeared that in the control group and in the lost group there was a significantly higher proportion of drunk drivers than in the intervention group, 3.3% (n=17), 3.5% (n=10) and 1.5% (n=10) (p=0.026), respectively. Survival analysis confirmed that psychological intervention had a significant impact on drunk driving (p=0.015), and the impact of the intervention was persistent also in the case of higher scores in Mild social deviance. In subjects with higher scores in impulsivity measures and alcohol-related problems the impact of short psychological intervention was not sufficient for preventing drunk driving. It can be concluded that psychological intervention used during the driving school studies is an effective primary prevention activity against drunk driving. However, for drivers with high scores in impulsivity measures and alcohol-related problems, the short psychological intervention is not sufficient in reducing drunk driving behavior.

Fatigued and drowsy driving: a survey of attitudes, opinions and behaviors.

Science.gov (United States)

Vanlaar, Ward; Simpson, Herb; Mayhew, Dan; Robertson, Robyn

2008-01-01

There is evidence suggesting that the problem of fatigued or drowsy driving is an important contributor to road crashes. However, not much is known about public perceptions of the issue. The purpose of this study was to obtain information on attitudes, opinions, and professed practices related to fatigued or drowsy driving. The data were gathered by means of a public opinion poll among a representative sample of 750 Ontario drivers. A majority of drivers (58.6%) admitted that they occasionally drive while fatigued or drowsy. Of greater importance, 14.5% of respondents admitted that they had fallen asleep or "nodded off" while driving during the past year. Nearly 2% were involved in a fatigue or drowsy driving related crash in the past year. Respondents were also asked about measures they take to overcome fatigue or drowsiness. Results indicate that relatively ineffective measures such as opening the window or playing music are the most popular; the most effective preventive measure--taking a rest--is the least popular. The prevalence of the behavior, coupled with the ineffective prevention measures favored by the public suggest there is a need for increasing their level of awareness and knowledge about the problem. Results from this study further emphasize the importance of increasing the fatigued and drowsy driving knowledge base and the need to educate the public about it.

From focus groups to production of a distracted driving video: Using teen input to drive injury prevention programming.

Science.gov (United States)

Stewart, Tanya Charyk; Harrington, Jane; Batey, Brandon; Merritt, Neil H; Parry, Neil G

2015-09-01

logical direction for our program, the production of a distracted driving video ("Distracted Driving: Josh's Story," http://youtu.be/BFPke9gBybc) to be incorporated into school presentations. Epidemiologic/prognostic study, level III.

In Patients with Cirrhosis, Driving Simulator Performance is Associated With Real-life Driving

DEFF Research Database (Denmark)

Lauridsen, Mette Enok Munk; Thacker, Leroy R; White, Melanie B

2016-01-01

BACKGROUND & AIMS: Minimal hepatic encephalopathy (MHE) has been linked to higher real-life rates of automobile crashes and poor performance in driving simulation studies, but the link between driving simulator performance and real-life automobile crashes has not been clearly established. Further......, not all patients with MHE are unsafe drivers, but it is unclear how to distinguish them from unsafe drivers. We investigated the link between performance on driving simulators and real-life automobile accidents and traffic violations. We also aimed to identify features of unsafe drivers with cirrhosis...... and evaluated changes in simulated driving skills and MHE status after 1 year. METHODS: We performed a study of outpatients with cirrhosis (n=205; median 55 years old; median model for end-stage liver disease score, 9.5; none with overt hepatic encephalopathy or alcohol or illicit drug use within previous 6...

Direct drive digital servo press with high parallel control

Science.gov (United States)

Murata, Chikara; Yabe, Jun; Endou, Junichi; Hasegawa, Kiyoshi

2013-12-01

Direct drive digital servo press has been developed as the university-industry joint research and development since 1998. On the basis of this result, 4-axes direct drive digital servo press has been developed and in the market on April of 2002. This servo press is composed of 1 slide supported by 4 ball screws and each axis has linearscale measuring the position of each axis with high accuracy less than μm order level. Each axis is controlled independently by servo motor and feedback system. This system can keep high level parallelism and high accuracy even with high eccentric load. Furthermore the 'full stroke full power' is obtained by using ball screws. Using these features, new various types of press forming and stamping have been obtained by development and production. The new stamping and forming methods are introduced and 'manufacturing' need strategy of press forming with high added value and also the future direction of press forming are also introduced.

On the Optimally Controlled Hydrostatic Mechanical Drive in Case of Flywheel Acceleration

Directory of Open Access Journals (Sweden)

V. A. Korsunskii

2016-01-01

Full Text Available An improving dynamic quality of vehicles and enhanced fuel efficiency are gained thanks to the combined power system (CPS, comprising a main energy source - internal combustion engine (ICE with an attained level of the power source - and an auxiliary energy source, i.e. an energy storage device (a flywheel.To solve this problem was developed a mathematical model of CPS comprising internal combustion engine and flywheel energy storage (FES with stepless drive.The stepless drive of the flywheel is made to be hydrostatic mechanical to raise the system efficiency. To reduce the drive weight and simplify the control system in the hydraulic part of the flywheel drive is used only one hydraulic unit being controlled.The paper presents a kinematic diagram of the track-type vehicle equipped with the CPS that has a hydrostatic mechanical drive of the flywheel and a mechanical transmission.A mathematical model of the system comprising an ICE, hydrostatic mechanical drive, and FES with stepless drive has been developed. This mathematical model was used to study the influence of ICE and flywheel drive parameters on the dynamic characteristics of the system.The paper estimates the impact of flywheel energy consumption, pressure in the hydraulic system, and control parameter of hydrostatic mechanical drive on the charging time of FES.The obtained piecewise linear law to control the regulation parameter of the hydraulic unit allows us to minimize the charging time of the flywheel at the short-term stops and in the parking area of a tracked vehicle equipped with a CPS.The causes affecting the performance of ‘ICE – drive – flywheel’ system in the course of the flywheel acceleration are a restricted maximum power of the engine, as well as a limited generating capacity, and a maximum flywheel drive hydro-system pressure.The obtained results allow us to determine rational parameters of the flywheel and the laws of drive control to provide their further

Testing device for control rod drives

International Nuclear Information System (INIS)

Hayakawa, Toshifumi.

1992-01-01

A testing device for control rod drives comprises a logic measuring means for measuring an output signal from a control rod drive logic generation circuit, a control means for judging the operation state of a control rod and a man machine interface means for outputting the result of the judgement. A driving instruction outputted from the control rod operation device is always monitored by the control means, and if the operation instruction is stopped, a testing signal is outputted to the control rod control device to simulate a control rod operation. In this case, the output signal of the control rod drive logic generation circuit is held in a control rod drive memory means and intaken into a logic analysis means for measurement and an abnormality is judged by the control means. The stopping of the control rod drive instruction is monitored and the operation abnormality of the control rod is judged, to mitigate the burden of an operator. Further, the operation of the control rod drive logic generation circuit can be confirmed even during a nuclear plant operation by holding the control rod drive instruction thereby enabling to improve maintenance efficiency. (N.H.)

Diplopia and driving: a problematic issue.

Science.gov (United States)

Righi, Stefano; Boffano, Paolo; Guglielmi, Valeria; Rossi, Paolo; Martorina, Massimo

2014-10-01

The aim of this article was to review the literature regarding diplopia and driving license and to review the West European legislations about this topic, in order to obtain appropriate indications for hospitals specialists and patients. A systematic review of articles published about diplopia and driving was performed. In addition a review of West European national legislations about driving license regulations for medical illnesses was performed, in addition to the European Union Directive on driving licenses. In the literature, the presence of diplopia has not been considered a reliable predictor of the safety of driving behavior, or it has not appeared to be a contraindication for driving according to some authors who were unable to demonstrate significant differences on driving simulator performance between subjects with chronic stable diplopia and control subjects. Nevertheless, in all western European legislations, acute diplopia constitutes an important limitation for driving, thus making the knowledge of current regulations fundamental for specialists involved in managing patients with diplopia. Ophthalmologists and maxillofacial/head and neck surgeons, may advise patients before hospital discharge about current legislations in their respective countries. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Risky driving behaviors in Tehran, Iran.

Science.gov (United States)

Shams, Mohsen; Rahimi-Movaghar, Vafa

2009-03-01

Iran has one of the highest fatality rates due to road traffic crashes (RTC) in the world. The disability adjusted life years (DALYs) for RTC in Iran is more than 1,300,000 years, which is more than that for any other disease such as cardiovascular or cancer. We evaluated risky driving behaviors in Tehran, the capital of Iran. A retrospective analysis was conducted based on the data obtained from the Tehran Police Safety Driving Department. Offenses and crashes were studied in different municipal districts in Tehran from March 2006 to March 2007. The inclusion criteria were risky driving behaviors fined by the police. Nonbehavioral offences were excluded. There were 3,821,798 offenses in Tehran. Not wearing a seat belt was the most common (59%) example of risky driving behavior, followed by tailgating, not wearing motorcycle helmets, talking on the cell phone while driving, overtaking from the wrong side, speeding, not driving between the lanes, weaving in and out of traffic, left deviation, and changing lanes without signals. The most common causes of RTC in Tehran are speeding, overtaking from the wrong side, and the rapid changing of driving lanes. The study factors effective in preventing risky driving behaviors in Tehran is recommended. The consideration of specific characteristics of the municipal districts is necessary to reduce risky driving behaviors.

Driving patterns in older adults with glaucoma.

Science.gov (United States)

van Landingham, Suzanne W; Hochberg, Chad; Massof, Robert W; Chan, Emilie; Friedman, David S; Ramulu, Pradeep Y

2013-02-21

The ability to drive is important for ensuring quality of life for many older adults. Glaucoma is prevalent in this age group and may affect driving. The purpose of this study is to determine if glaucoma and glaucomatous visual field (VF) loss are associated with driving cessation, limitations, and deference to another driver in older adults. Cross-sectional study. Eighty-one glaucoma subjects and 58 glaucoma suspect controls between age 60 and 80 reported if they had ceased driving, limited their driving in various ways, or preferred another to drive. Twenty-three percent of glaucoma subjects and 6.9% of suspects had ceased driving (p = 0.01). Glaucoma subjects also had more driving limitations than suspects (2.0 vs. 1.1, p = 0.007). In multivariable models, driving cessation was more likely for glaucoma subjects as compared to suspects (OR = 4.0; 95% CI = 1.1-14.7; p = 0.03). The odds of driving cessation doubled with each 5 decibel (dB) decrement in the better-eye VF mean deviation (MD) (OR = 2.0; 95% CI = 1.4-2.9; p driving limitations (OR = 4.7; 95% CI = 1.3-16.8; p = 0.02). The likelihood of reporting more limitations increased with the VF loss severity (OR = 1.6 per 5 dB decrement in the better-eye VF MD; 95% CI = 1.1-2.4; p = 0.02). Neither glaucoma nor VF MD was associated with other driver preference (p > 0.1 for both). Glaucoma and glaucomatous VF loss are associated with greater likelihood of driving cessation and greater limitation of driving in the elderly. Further prospective study is merited to assess when and why people with glaucoma change their driving habits, and to determine if their observed self-regulation of driving is adequate to ensure safety.

Output Feedback Control of Electro-Hydraulic Cylinder Drives using the Twisting Algorithm

DEFF Research Database (Denmark)

Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

2014-01-01

contributions in literature. This paper considers the twisting algorithm when applied directly for output feedback control, and with the design based on a reduced order model representation of an arbitrary valve driven hydraulic cylinder drive. The consequence of implementing such a controller with the well......This paper discusses the utilization of the so-called twisting algorithm when applied in output feedback position control schemes for electro-hydraulic cylinder drives. The twisting controller was the first second order sliding controller ever introduced, and can structure-wise be considered...... feedback controller may be successfully applied to hydraulic valve driven cylinder drives, with performance being on the level with a conventional surface based first order sliding mode controller....

Perceptual and Cognitive Impairments and Driving

Science.gov (United States)

Korner-Bitensky, Nicol; Coopersmith, Henry; Mayo, Nancy; Leblanc, Ginette; Kaizer, Franceen

1990-01-01

Perceptual and cognitive disorders that frequently accompany stroke and head injury influence an individual's ability to drive a motor vehicle. Canadian physicians are legally responsible for identifying patients who are potentially unsafe to drive and, if they fail to do so, may be held liable in a civil action suit. The authors review the guidelines for physicians evaluating a patient's fitness to drive after brain injury. They also examine the actions a physician should take when a patient with perceptual and cognitive problems wants to drive. Ultimately, by taking these actions, physicians will help to prevent driving accidents. PMID:21234047

Analysis of Vehicle Steering and Driving Bifurcation Characteristics

Directory of Open Access Journals (Sweden)

Xianbin Wang

2015-01-01

Full Text Available The typical method of vehicle steering bifurcation analysis is based on the nonlinear autonomous vehicle model deriving from the classic two degrees of freedom (2DOF linear vehicle model. This method usually neglects the driving effect on steering bifurcation characteristics. However, in the steering and driving combined conditions, the tyre under different driving conditions can provide different lateral force. The steering bifurcation mechanism without the driving effect is not able to fully reveal the vehicle steering and driving bifurcation characteristics. Aiming at the aforementioned problem, this paper analyzed the vehicle steering and driving bifurcation characteristics with the consideration of driving effect. Based on the 5DOF vehicle system dynamics model with the consideration of driving effect, the 7DOF autonomous system model was established. The vehicle steering and driving bifurcation dynamic characteristics were analyzed with different driving mode and driving torque. Taking the front-wheel-drive system as an example, the dynamic evolution process of steering and driving bifurcation was analyzed by phase space, system state variables, power spectral density, and Lyapunov index. The numerical recognition results of chaos were also provided. The research results show that the driving mode and driving torque have the obvious effect on steering and driving bifurcation characteristics.

Low backlash direct drive actuator

Science.gov (United States)

Kuklo, Thomas C.

1994-01-01

A low backlash direct drive actuator is described which comprises a motor such as a stepper motor having at least 200 steps per revolution; a two part hub assembly comprising a drive hub coaxially attached to the shaft of the motor and having a plurality of drive pins; a driven hub having a plurality of bores in one end thereof in alignment with the drive pins in the drive hub and a threaded shaft coaxially mounted in an opposite end of the driven hub; and a housing having a central bore therein into which are fitted the drive hub and driven hub, the housing having a motor mount on one end thereof to which is mounted the stepper motor, and a closed end portion with a threaded opening therein coaxial with the central bore in the housing and receiving therein the threaded shaft attached to the driven hub. Limit switches mounted to the housing cooperate with an enlarged lip on the driven hub to limit the lateral travel of the driven hub in the housing, which also acts to limit the lateral travel of the threaded shaft which functions as a lead screw.

Continuing to drive while sleepy: the influence of sleepiness countermeasures, motivation for driving sleepy, and risk perception.

Science.gov (United States)

Watling, Christopher N; Armstrong, Kerry A; Obst, Patricia L; Smith, Simon S

2014-12-01

Driver sleepiness is a major contributor to road crashes. The current study sought to examine the association between perceptions of effectiveness of six sleepiness countermeasures and their relationship with self-reports of continuing to drive while sleepy among 309 drivers after controlling for the influence of age, sex, motivation for driving sleepy, and risk perception of sleepy driving. The results demonstrate that the variables of age, sex, motivation, and risk perception were significantly associated with self-reports of continuing to drive while sleepy and only one countermeasure was associated with self-reports of continuing to drive while sleepy. Further, it was found that age differences in self-reports of continuing to drive while sleepy was mediated by participants' motivation and risk perception. These findings highlight modifiable factors that could be focused on with interventions that seek to modify drivers' attitudes and behaviours of driving while sleepy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Driving error and anxiety related to iPod mp3 player use in a simulated driving experience.

Science.gov (United States)

Harvey, Ashley R; Carden, Randy L

2009-08-01

Driver distraction due to cellular phone usage has repeatedly been shown to increase the risk of vehicular accidents; however, the literature regarding the use of other personal electronic devices while driving is relatively sparse. It was hypothesized that the usage of an mp3 player would result in an increase in not only driving error while operating a driving simulator, but driver anxiety scores as well. It was also hypothesized that anxiety scores would be positively related to driving errors when using an mp3 player. 32 participants drove through a set course in a driving simulator twice, once with and once without an iPod mp3 player, with the order counterbalanced. Number of driving errors per course, such as leaving the road, impacts with stationary objects, loss of vehicular control, etc., and anxiety were significantly higher when an iPod was in use. Anxiety scores were unrelated to number of driving errors.

Implicit attitudes towards risky and safe driving

DEFF Research Database (Denmark)

Martinussen, Laila Marianne; Sømhovd, Mikael Julius; Møller, Mette

; further, self-reports of the intention to drive safely (or not) are socially sensitive. Therefore, we examined automatic preferences towards safe and risky driving with a Go/No-go Association Task (GNAT). The results suggest that (1) implicit attitudes towards driving behavior can be measured reliably...... with the GNAT; (2) implicit attitudes towards safe driving versus towards risky driving may be separable constructs. We propose that research on driving behavior may benefit from routinely including measures of implicit cognition. A practical advantage is a lesser susceptibility to social desirability biases......, compared to self-report methods. Pending replication in future research, the apparent dissociation between implicit attitudes towards safe versus risky driving that we observed may contribute to a greater theoretical understanding of the causes of unsafe and risky driving behavior....

Comparison of Unsafe Driving Across Medical Conditions.

Science.gov (United States)

Moon, Sanghee; Ranchet, Maud; Tant, Mark; Akinwuntan, Abiodun E; Devos, Hannes

2017-09-01

To compare risks of unsafe driving in patients with medical conditions. This large population-based study included all patients who were referred for a fitness-to-drive evaluation at an official driving evaluation center in 2013 and 2014. Risks of unsafe driving included physician's fitness-to-drive recommendation, comprehensive fitness-to-drive decision, motor vehicle crash history, and traffic violation history. A total of 6584 patients were included in the study. Risks of unsafe driving were significantly different across medical conditions (Pdriving. Patients with psychiatric conditions or substance abuse did worse on most driving safety outcomes, despite their low representation in the total sample (359 [6%] and 46 [1%], respectively). The risk of unsafe driving varied greatly across medical conditions. Sensitization campaigns, education, and medical guidelines for physicians and driver licensing authorities are warranted to identify patients at risk, especially for those with psychiatric conditions and substance abuse problems. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

HIL Simulation of Power Electronics and Electric Drives for Automotive Applications

Directory of Open Access Journals (Sweden)

Frank Puschmann

2012-12-01

Full Text Available Hardware-in-the-loop simulation is today a standard method for testing electronic equipment in the automotive industry. Since electric drives and power electronic devices are more and more important in automotive applications, these kinds of systems have to be integrated into the hardware-in-the-loop simulation. Power converters and electric drives are used in many different applications in vehicles today (hybrid electric or electric powertrain, electric steering systems, DC-DC converters, etc.. The wide range of applications, topologies, and power levels results in various different approaches and solutions for hardware-in-the-loop testing. This paper gives an overview of hardware-in-the-loop simulation of power electronics and electric drives in the automotive industry. The currently available technologies are described and future challenges are outlined.

MODELING CONTROLLED ASYNCHRONOUS ELECTRIC DRIVES WITH MATCHING REDUCERS AND TRANSFORMERS

Directory of Open Access Journals (Sweden)

V. S. Petrushin

2015-04-01

Full Text Available Purpose. Working out of mathematical models of the speed-controlled induction electric drives ensuring joint consideration of transformers, motors and loadings, and also matching reducers and transformers, both in static, and in dynamic regimes for the analysis of their operating characteristics. Methodology. At mathematical modelling are considered functional, mass, dimensional and cost indexes of reducers and transformers that allows observing engineering and economic aspects of speed-controlled induction electric drives. The mathematical models used for examination of the transitive electromagnetic and electromechanical processes, are grounded on systems of nonlinear differential equations with nonlinear coefficients (parameters of equivalent circuits of motors, varying in each operating point, including owing to appearances of saturation of magnetic system and current displacement in a winding of a rotor of an induction motor. For the purpose of raise of level of adequacy of models a magnetic circuit iron, additional and mechanical losses are considered. Results. Modelling of the several speed-controlled induction electric drives, different by components, but working on a loading equal on character, magnitude and a demanded control range is executed. At use of characteristic families including mechanical, at various parameters of regulating on which performances of the load mechanism are superimposed, the adjusting characteristics representing dependences of a modification of electrical, energy and thermal magnitudes from an angular speed of motors are gained. Originality. The offered complex models of speed-controlled induction electric drives with matching reducers and transformers, give the chance to realize well-founded sampling of components of drives. They also can be used as the design models by working out of speed-controlled induction motors. Practical value. Operating characteristics of various speed-controlled induction electric

Correlates of Marijuana Drugged Driving and Openness to Driving While High: Evidence from Colorado and Washington.

Directory of Open Access Journals (Sweden)

Kevin C Davis

Full Text Available A potential unintended consequence of legalizing recreational marijuana is increased marijuana-related driving impairment. Some states where recreational marijuana is legal have begun implementing interventions to mitigate driving under the influence (DUI of marijuana, including media campaigns to increase knowledge about DUI laws. However, little is known about the associations between knowledge of DUI laws and marijuana DUI behavior. In this study, we provide new data from a survey of marijuana users in Colorado and Washington to examine associations between marijuana drugged driving and two potential behavioral precursors of marijuana DUI. We also explore other factors that may influence marijuana DUI.Data are from an online survey of marijuana users in Colorado and Washington. Respondents who reported any marijuana use in the past 30 days (n = 865 served as the analytic sample. We examined prevalence of two behavioral outcomes: (1 any driving of a motor vehicle while high in the past year and (2 driving a motor vehicle within 1 hour of using marijuana 5 or more times in the past month. Additional outcomes measuring willingness to drive while high were also assessed. Logistic regressions were used to estimate each outcome as a function of two multi-item scales measuring knowledge of the legal consequences of driving high and perceptions that driving while high is not safe. Additional covariates for potential confounders were included in each model.Prevalence of past-year driving while under the influence of marijuana was 43.6% among respondents. The prevalence of driving within 1 hour of using marijuana at least 5 times in the past month was 23.9%. Increased perception that driving high is unsafe was associated with lower odds of past-year marijuana DUI (OR = 0.31, P < 0.01 and lower past-month odds of driving 5 or more times within 1 hour of using marijuana (OR = 0.26, P < 0.01. Increased knowledge of marijuana DUI laws was also associated

An Energy Efficient Hydraulic Winch Drive Concept Based on a Speed-variable Switched Differential Pump

DEFF Research Database (Denmark)

Schmidt, Lasse; Andersen, Torben O.; Pedersen, Henrik Clemmensen

2017-01-01

controls. Such solutions are typically constituted by many and rather expensive components, and are furthermore often suffering from low frequency dynamics. In this paper an alternative solution is proposed for winch drive operation, which is based on the so-called speed-variable switched differential pump......, originally designed for direct drive of hydraulic differential cylinders. This concept utilizes three pumps, driven by a single electric servo drive. The concept is redesigned for usage in winch drives, driven by flow symmetric hydraulic motors and single directional loads as commonly seen in e.g. active...... heave compensation applications. A general drive configuration approach is presented, along with a proper control strategy and design. The resulting concept is evaluated when applied for active heave compensation. Results demonstrate control performance on level with conventional valve solutions...

German taxi drivers' experiences and expressions of driving anger: Are the driving anger scale and the driving anger expression inventory valid measures?

Science.gov (United States)

Brandenburg, Stefan; Oehl, Michael; Seigies, Kristin

2017-11-17

The objective of this article was 2-fold: firstly, we wanted to examine whether the original Driving Anger Scale (DAS) and the original Driving Anger Expression Inventory (DAX) apply to German professional taxi drivers because these scales have previously been given to professional and particularly to nonprofessional drivers in different countries. Secondly, we wanted to examine possible differences in driving anger experience and expression between professional German taxi drivers and nonprofessional German drivers. We applied German versions of the DAS, the DAX, and the State-Trait Anger Expression Inventory (STAXI) to a sample of 138 professional German taxi drivers. We then compared their ratings to the ratings of a sample of 1,136 nonprofessional German drivers (Oehl and Brandenburg n.d. ). Regarding our first objective, confirmatory factor analysis shows that the model fit of the DAS is better for nonprofessional drivers than for professional drivers. The DAX applies neither to professional nor to nonprofessional German drivers properly. Consequently, we suggest modified shorter versions of both scales for professional drivers. The STAXI applies to both professional and nonprofessional drivers. With respect to our second objective, we show that professional drivers experience significantly less driving anger than nonprofessional drivers, but they express more driving anger. We conclude that the STAXI can be applied to professional German taxi drivers. In contrast, for the DAS and the DAX we found particular shorter versions for professional taxi drivers. Especially for the DAX, most statements were too strong for German drivers to agree to. They do not show behaviors related to driving anger expression as they are described in the DAX. These problems with the original American DAX items are in line with several other studies in different countries. Future investigations should examine whether (professional) drivers from further countries express their anger

Hypnotics and driving safety: meta-analyses of randomized controlled trials applying the on-the-road driving test.

Science.gov (United States)

Verster, Joris C; Veldhuijzen, Dieuwke S; Patat, Alain; Olivier, Berend; Volkerts, Edmund R

2006-01-01

Many people who use hypnotics are outpatients and are likely to drive a car the day after drug intake. The purpose of these meta-analyses was to determine whether or not this is safe. Placebo-controlled, randomized, double-blind trials were selected if using the on-the-road driving test to determine driving ability the day following one or two nights of treatment administration. Primary outcome measure of the driving test was the Standard Deviation of Lateral Position (SDLP); i.e., the weaving of the car. Fixed effects model meta-analyses were performed. Effect size (ES) was computed using mean standardized (weighted) difference scores between treatment and corresponding placebo SDLP values. Ten studies, published from 1984 to 2002 (207 subjects), were included in the meta-analyses. The morning following bedtime administration, i.e. 10-11 hours after dosing, significant driving impairment was found for the recommended dose of various benzodiazepine hypnotics (ES=0.42; 95% Confidence Interval (CI)=0.14 to 0.71). Twice the recommended dose impaired driving both in the morning (ES=0.68; CI=0.39 to 0.97) and afternoon, i.e. 16-17 hours after dosing (ES=0.57; CI=0.26 to 0.88). Zopiclone 7.5 mg also impaired driving in the morning (ES=0.89; CI=0.54 to 1.23). Zaleplon (10 and 20 mg) and zolpidem (10 mg) did not affect driving performance the morning after dosing. Following middle-of-the-night administration, significantly impaired driving performance was found for zopiclone 7.5 mg (ES=1.51, CI=0.85 to 2.17), zolpidem 10 mg (ES=0.66, CI=0.13 to 1.19) and zolpidem 20 mg (ES=1.16, CI=0.60 to 1.72). Zaleplon (10 and 20 mg) did not affect driving performance. The analyses show that driving a car the morning following nocturnal treatment with benzodiazepines and zopiclone is unsafe, whereas the recommended dose of zolpidem (10 mg) and zaleplon (10 mg) do not affect driving ability.

Texting while driving: is speech-based text entry less risky than handheld text entry?

Science.gov (United States)

He, J; Chaparro, A; Nguyen, B; Burge, R J; Crandall, J; Chaparro, B; Ni, R; Cao, S

2014-11-01

Research indicates that using a cell phone to talk or text while maneuvering a vehicle impairs driving performance. However, few published studies directly compare the distracting effects of texting using a hands-free (i.e., speech-based interface) versus handheld cell phone, which is an important issue for legislation, automotive interface design and driving safety training. This study compared the effect of speech-based versus handheld text entries on simulated driving performance by asking participants to perform a car following task while controlling the duration of a secondary text-entry task. Results showed that both speech-based and handheld text entries impaired driving performance relative to the drive-only condition by causing more variation in speed and lane position. Handheld text entry also increased the brake response time and increased variation in headway distance. Text entry using a speech-based cell phone was less detrimental to driving performance than handheld text entry. Nevertheless, the speech-based text entry task still significantly impaired driving compared to the drive-only condition. These results suggest that speech-based text entry disrupts driving, but reduces the level of performance interference compared to text entry with a handheld device. In addition, the difference in the distraction effect caused by speech-based and handheld text entry is not simply due to the difference in task duration. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fundamentals of electrical drives

CERN Document Server

Veltman, André; De Doncker, Rik W

2007-01-01

Provides a comprehensive introduction to various aspects of electrical drive systems. This volume provides a presentation of dynamic generic models that cover all major electrical machine types and modulation/control components of a drive as well as dynamic and steady state analysis of transformers and electrical machines.

Introduction matters: Manipulating trust in automation and reliance in automated driving.

Science.gov (United States)

Körber, Moritz; Baseler, Eva; Bengler, Klaus

2018-01-01

Trust in automation is a key determinant for the adoption of automated systems and their appropriate use. Therefore, it constitutes an essential research area for the introduction of automated vehicles to road traffic. In this study, we investigated the influence of trust promoting (Trust promoted group) and trust lowering (Trust lowered group) introductory information on reported trust, reliance behavior and take-over performance. Forty participants encountered three situations in a 17-min highway drive in a conditionally automated vehicle (SAE Level 3). Situation 1 and Situation 3 were non-critical situations where a take-over was optional. Situation 2 represented a critical situation where a take-over was necessary to avoid a collision. A non-driving-related task (NDRT) was presented between the situations to record the allocation of visual attention. Participants reporting a higher trust level spent less time looking at the road or instrument cluster and more time looking at the NDRT. The manipulation of introductory information resulted in medium differences in reported trust and influenced participants' reliance behavior. Participants of the Trust promoted group looked less at the road or instrument cluster and more at the NDRT. The odds of participants of the Trust promoted group to overrule the automated driving system in the non-critical situations were 3.65 times (Situation 1) to 5 times (Situation 3) higher. In Situation 2, the Trust promoted group's mean take-over time was extended by 1154 ms and the mean minimum time-to-collision was 933 ms shorter. Six participants from the Trust promoted group compared to no participant of the Trust lowered group collided with the obstacle. The results demonstrate that the individual trust level influences how much drivers monitor the environment while performing an NDRT. Introductory information influences this trust level, reliance on an automated driving system, and if a critical take-over situation can be

Pilot Efficacy of a DriveFocus™ Intervention on the Driving Performance of Young Drivers

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Liliana Alvarez

2018-05-01

Full Text Available Road traffic injuries are the leading cause of death for youth between the ages of 15 and 29 around the world. A need remains for evidence-based interventions that can improve the underlying skills of young drivers, including hazard perception and anticipation. This pilot study investigated the preliminary impact of a six session DriveFocus™ intervention on the ability of young novice drivers (mean age = 18.6, SD = 2.12 to detect (visual scanning, and respond (adjustment to stimuli to critical roadway information. Using a CDS-200 DriveSafety™ simulator, drives were recorded and sent to a blinded evaluator (occupational therapist, who scored the recorded drives for number and type (visual scanning and adjustment to stimuli of errors. We observed a statistically significant decline in the number of visual scanning [t(34 = 2.853, p = 0.007], adjustment to stimuli [t(34 = 3.481, p = 0.001], and total driving errors [t(34 = 3.481, p = 0.002], among baseline and post-test 2.

The prosocial and aggressive driving inventory (PADI): a self-report measure of safe and unsafe driving behaviors.

Science.gov (United States)

Harris, Paul B; Houston, John M; Vazquez, Jose A; Smither, Janan A; Harms, Amanda; Dahlke, Jeffrey A; Sachau, Daniel A

2014-11-01

Surveys of 1217 undergraduate students supported the reliability (inter-item and test-retest) and validity of the Prosocial and Aggressive Driving Inventory (PADI). Principal component analyses on the PADI items yielded two scales: Prosocial Driving (17 items) and Aggressive Driving (12 items). Prosocial Driving was associated with fewer reported traffic accidents and violations, with participants who were older and female, and with lower Boredom Susceptibility and Hostility scores, and higher scores on Agreeableness, Conscientiousness, Openness, and Neuroticism. Aggressive Driving was associated with more frequent traffic violations, with female participants, and with higher scores on Competitiveness, Sensation Seeking, Hostility, and Extraversion, and lower scores on Conscientiousness, Agreeableness, and Openness. The theoretical and practical implications of the PADI's dual focus on safe and unsafe driving are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Naturalistic drive cycle synthesis for pickup trucks.

Science.gov (United States)

Liu, Zifan; Ivanco, Andrej; Filipi, Zoran

2015-09-01

Future pick-up trucks are meeting much stricter fuel economy and exhaust emission standards. Design tradeoffs will have to be carefully evaluated to satisfy consumer expectations within the regulatory and cost constraints. Boundary conditions will obviously be critical for decision making: thus, the understanding of how customers are driving in naturalistic settings is indispensable. Federal driving schedules, while critical for certification, do not capture the richness of naturalistic cycles, particularly the aggressive maneuvers that often shape consumer perception of performance. While there are databases with large number of drive cycles, applying all of them directly in the design process is impractical. Therefore, representative drive cycles that capture the essence of the naturalistic driving should be synthesized from naturalistic driving data. Naturalistic drive cycles are firstly categorized by investigating their micro-trip components, defined as driving activities between successive stops. Micro-trips are expected to characterize underlying local traffic conditions, and separate different driving patterns. Next, the transitions from one vehicle state to another vehicle state in each cycle category are captured with Transition Probability Matrix (TPM). Candidate drive cycles can subsequently be synthesized using Markov Chain based on TPMs for each category. Finally, representative synthetic drive cycles are selected through assessment of significant cycle metrics to identify the ones with smallest errors. This paper provides a framework for synthesis of representative drive cycles from naturalistic driving data, which can subsequently be used for efficient optimization of design or control of pick-up truck powertrains. Manufacturers will benefit from representative drive cycles in several aspects, including quick assessments of vehicle performance and energy consumption in simulations, component sizing and design, optimization of control strategies, and

Predictions of fast wave heating, current drive, and current drive antenna arrays for advanced tokamaks

International Nuclear Information System (INIS)

Batchelor, D.B.; Baity, F.W.; Carter, M.D.

1994-01-01

The objective of the advanced tokamak program is to optimize plasma performance leading to a compact tokamak reactor through active, steady state control of the current profile using non-inductive current drive and profile control. To achieve these objectives requires compatibility and flexibility in the use of available heating and current drive systems--ion cyclotron radio frequency (ICRF), neutral beams, and lower hybrid. For any advanced tokamak, the following are important challenges to effective use of fast waves in various roles of direct electron heating, minority ion heating, and current drive: (1) to employ the heating and current drive systems to give self-consistent pressure and current profiles leading to the desired advanced tokamak operating modes; (2) to minimize absorption of the fast waves by parasitic resonances, which limit current drive; (3) to optimize and control the spectrum of fast waves launched by the antenna array for the required mix of simultaneous heating and current drive. The authors have addressed these issues using theoretical and computational tools developed at a number of institutions by benchmarking the computations against available experimental data and applying them to the specific case of TPX

Naturalistic distraction and driving safety in older drivers.

Science.gov (United States)

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.

Electrohydraulic drive system with planetary superposed gears

Energy Technology Data Exchange (ETDEWEB)

Graetz, A.; Klimek, K.H.; Welz, H.

1989-01-01

To prevent drive problems in ploughs the drives must be designed in such a way as to compensate for asymmetries. If electromechanical drives are replaced by an electrohydraulic drive system with superposed planetary gears and hydrostatic torque reaction supports the following advantages occur: load-free acceleration, load equalisation between main and auxiliary drive, overload protection, and reduction of systems vibrations. 2 figs., 2 tabs.

Sleep apnoea and driving risk: the need for regulation

Directory of Open Access Journals (Sweden)

Walter T. McNicholas

2015-12-01

Full Text Available Obstructive sleep apnoea syndrome (OSAS is a highly prevalent chronic respiratory disorder with prevalence among adult males of ≥10%. The most common daytime symptom associated with OSAS is excessive sleepiness, which in more severe manifestations can result in sleepiness at the wheel while driving and probably contributes to the substantial increase in accident risk among patients with OSAS. Fortunately, current evidence indicates that successful therapy of OSAS, particularly with continuous positive airway pressure, can bring the accident risk down to levels similar to an equivalent general population. The recognition of the increased driving accident risk in OSAS prompted the Transport and Mobility Directorate of the European Commission to establish a working group on this topic in 2012, which ultimately led to a revision of Annex III of the EU Driving Licence Directive, which is subject to mandatory implementation by European Union member states by December 2015. This directive specifies that patients with moderate or severe OSAS associated with significant daytime sleepiness should be prohibited from driving until effective therapy is established. These new regulations are designed to balance the legitimate objective of public safety with not penalising OSAS patients who are complying with effective therapy. Successful implementation of regulations on driving in OSAS patients must also include measures to educate relevant stakeholders including patients, medical personnel, traffic police and employers in the transport industry. The key objective is to encourage patients with possible OSAS to seek diagnosis and treatment and not to inhibit OSAS patients from coming forward.

Sleep apnoea and driving risk: the need for regulation.

Science.gov (United States)

McNicholas, Walter T; Rodenstein, Daniel

2015-12-01

Obstructive sleep apnoea syndrome (OSAS) is a highly prevalent chronic respiratory disorder with prevalence among adult males of ≥10%. The most common daytime symptom associated with OSAS is excessive sleepiness, which in more severe manifestations can result in sleepiness at the wheel while driving and probably contributes to the substantial increase in accident risk among patients with OSAS. Fortunately, current evidence indicates that successful therapy of OSAS, particularly with continuous positive airway pressure, can bring the accident risk down to levels similar to an equivalent general population. The recognition of the increased driving accident risk in OSAS prompted the Transport and Mobility Directorate of the European Commission to establish a working group on this topic in 2012, which ultimately led to a revision of Annex III of the EU Driving Licence Directive, which is subject to mandatory implementation by European Union member states by December 2015. This directive specifies that patients with moderate or severe OSAS associated with significant daytime sleepiness should be prohibited from driving until effective therapy is established. These new regulations are designed to balance the legitimate objective of public safety with not penalising OSAS patients who are complying with effective therapy. Successful implementation of regulations on driving in OSAS patients must also include measures to educate relevant stakeholders including patients, medical personnel, traffic police and employers in the transport industry. The key objective is to encourage patients with possible OSAS to seek diagnosis and treatment and not to inhibit OSAS patients from coming forward. Copyright ©ERS 2015.

Hydraulic pressure control unit for control rod drive

International Nuclear Information System (INIS)

Watabe, Yukio.

1990-01-01

The pressure invention concerns a hydraulic pressure control unit for control rod drives in BWR type reactors. The space above a floating piston possessed by an accumulator and the housing of control rod drives are connected by means of a pipeline. The pipeline has a scram valve which is opened upon occurrence of reactor scram. A pump is disposed between the accumulator and the scram valve for communicating a discharge port to apply a high pressure water to the accumulator. According to the present invention, a control unit is disposed between the scram valve and the housing of the control rod drives in the hydraulic pressure control unit for maintaining the cross sectional area of the flow channel of the pipeline to a usual size when the pressure in a pressure vessel is under a rated operation pressure, while limiting the cross sectional area of the flow channel when the pressure is lower than that in the rated operation. Thus, whole insertion of the control rod substantially at a constant speed is enabled irrespective of the level of the pressure in the pressure vessel. (I.S.)

Real-world driving behaviour

NARCIS (Netherlands)

Rijkeboer, R.C.; Hendriksen, P.; Gense, N.L.J.

2001-01-01

With increasing complexity of engine management system there is a tendency for traditional driving cyles to become further and further removed from reality. So for a sensible evaluation of emissions and fuel consumption of road vehicles in the field there is an urgent need for 'real-world' driving

Comparison of superconducting generators and permanent magnet generators for 10-MW direct-drive wind turbines

DEFF Research Database (Denmark)

Liu, Dong; Polinder, Henk; Abrahamsen, Asger Bech

2016-01-01

Large offshore direct-drive wind turbines of 10-MW power levels are being extensively proposed and studied because of a reduced cost of energy. Conventional permanent magnet generators currently dominating the direct-drive wind turbine market are still under consideration for such large wind...... turbines. In the meantime, superconducting generators (SCSGs) have been of particular interest to become a significant competitor because of their compactness and light weight. This paper compares the performance indicators of these two direct-drive generator types in the same 10-MW wind turbine under...... the same design and optimization method. Such comparisons will be interesting and insightful for commercialization of superconducting generators and for development of future wind energy industry, although SCSGs are still far from a high technology readiness level. The results show that the SCSGs may...

Effect of ethylic alcohol on attentive functions involved in driving abilities.

Science.gov (United States)

Bivona, Umberto; Garbarino, Sergio; Rigon, Jessica; Buzzi, Maria Gabriella; Onder, Graziano; Matteis, Maria; Catani, Sheila; Giustini, Marco; Mancardi, Giovanni Luigi; Formisano, Rita

2015-01-01

The burden of injuries due to drunk drivers has been estimated only indirectly. Indeed, alcohol is considered one of the most important contributing cause of car crash injuries and its effect on cognitive functions needs to be better elucidated. Aims of the study were i) to examine the effect of alcohol on attentive abilities involved while driving, and ii) to investigate whether Italian law limits for safe driving are sufficiently accurate to prevent risky behaviours and car crash risk while driving. We conducted a cross-over study at IRCCS Fondazione Santa Lucia Rehabilitation Hospital in Rome. Thirty-two healthy subjects were enrolled in this experiment. Participants were submitted to an attentive test battery assessing attention before taking Ethylic Alcohol (EA-) and after taking EA (EA+). In the EA+ condition subjects drank enough wine until the blood alcohol concentration, measured by means of Breath Analyzer, was equal to or higher than 0.5 g/l. Data analysis revealed that after alcohol assumption, tonic and phasic alertness, selective, divided attention and vigilance were significantly impaired when BAC level was at least 0.5 g/l. These data reveal that alcohol has a negative effect on attentive functions which are primarily involved in driving skills and that Italian law limits are adequate to prevent risky driving behaviour.

Driver’s Cognitive Workload and Driving Performance under Traffic Sign Information Exposure in Complex Environments: A Case Study of the Highways in China

Directory of Open Access Journals (Sweden)

Nengchao Lyu

2017-02-01

Full Text Available Complex traffic situations and high driving workload are the leading contributing factors to traffic crashes. There is a strong correlation between driving performance and driving workload, such as visual workload from traffic signs on highway off-ramps. This study aimed to evaluate traffic safety by analyzing drivers’ behavior and performance under the cognitive workload in complex environment areas. First, the driving workload of drivers was tested based on traffic signs with different quantities of information. Forty-four drivers were recruited to conduct a traffic sign cognition experiment under static controlled environment conditions. Different complex traffic signs were used for applying the cognitive workload. The static experiment results reveal that workload is highly related to the amount of information on traffic signs and reaction time increases with the information grade, while driving experience and gender effect are not significant. This shows that the cognitive workload of subsequent driving experiments can be controlled by the amount of information on traffic signs. Second, driving characteristics and driving performance were analyzed under different secondary task driving workload levels using a driving simulator. Drivers were required to drive at the required speed on a designed highway off-ramp scene. The cognitive workload was controlled by reading traffic signs with different information, which were divided into four levels. Drivers had to make choices by pushing buttons after reading traffic signs. Meanwhile, the driving performance information was recorded. Questionnaires on objective workload were collected right after each driving task. The results show that speed maintenance and lane deviations are significantly different under different levels of cognitive workload, and the effects of driving experience and gender groups are significant. The research results can be used to analyze traffic safety in highway

Energy Saving Potential in Knuckle Boom Cranes using a Novel Pump Controlled Cylinder Drive

Directory of Open Access Journals (Sweden)

Søren Ketelsen

2018-04-01

Full Text Available This paper is considering the application of a novel pump controlled cylinder drive, the so-called Speed-variable Switched Differential Pump (SvSDP, for knuckle boom crane actuation. Especially the control system for the SvSDP drive is considered, and aiming on improving energy efficiency a refinement of the existing control structure is proposed. An energy efficient sizing algorithm for the SvSDP drive is developed, and fundamental differences between the achievable operating range for the SvSDP drive compared to a conventional valve-cylinder drive are discussed. A case study is conducted with knuckle boom crane actuation, and compared to a conventional valve actuation. Simulation results show that the motion tracking performance is on a similar level compared to the valve actuation approach, while the energy consumption is drastically decreased. For the given test trajectory the valve actuation system consumes 0.79 kWh of electrical energy, while the SvSDP drive consume 0.06 kWh, if ideal energy recovery and storage is assumed.

Synthesis of Servo Pneumatic/Hydraulic Drive

Directory of Open Access Journals (Sweden)

K D. Efremova

2017-01-01

Full Text Available Servo pneumatic and / or hydraulic drives are widely used in modern engineering and process control. The efficiency of using pneumatic / hydraulic drives depends on their parameters and characteristics. To select the optimal drive parameters, various methods are used, based on finding the minimum of the target (target or criteria function.The objective of this paper was to apply one crucial criterion (target function that provides determination of optimal parameters of the pneumatic / hydraulic drive with the translational motion of the end-effector as well as its use in the synthesis of the servo pneumatic cylinder. The article shows the form of the target function representing a set of drive parameters that do not have direct relationships with each other in a dimensionless form for the pneumatic / hydraulic drive with the translational motion of the end-effector. To calculate the parameters of the servo drive close to the optimal ones, a two-criteria LPτ search was used. As criteria, were used the decisive criterion - the proposed target function, and the power developed by the actuator of the pneumatic / hydraulic drive, which were presented in a dimensionless form. It is shown that the criterion for solution optimality is the minimum distance of the selected point in the space of the normalized criteria from the origin. This point was determined. In addition to the proposed criteria, non-formalised requirements were taken into account: actual and mass-produced components of drive, in terms of which its parameters close to the optimal ones were determined, and the maximum relative error of the obtained useful power value of the servo pneumatic drive was estimated. The paper presents design features of two types of the servo pneumatic drive created, taking into account the proposed target function, implemented according to the schemes "hidden" and "spaced apart". The experimental static characteristic of the servo pneumatic drive is

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

Science.gov (United States)

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/.

Turbulent current drive mechanisms

Science.gov (United States)

McDevitt, Christopher J.; Tang, Xian-Zhu; Guo, Zehua

2017-08-01

Mechanisms through which plasma microturbulence can drive a mean electron plasma current are derived. The efficiency through which these turbulent contributions can drive deviations from neoclassical predictions of the electron current profile is computed by employing a linearized Coulomb collision operator. It is found that a non-diffusive contribution to the electron momentum flux as well as an anomalous electron-ion momentum exchange term provide the most efficient means through which turbulence can modify the mean electron current for the cases considered. Such turbulent contributions appear as an effective EMF within Ohm's law and hence provide an ideal means for driving deviations from neoclassical predictions.

Large-Scale Battery System Development and User-Specific Driving Behavior Analysis for Emerging Electric-Drive Vehicles

Directory of Open Access Journals (Sweden)

Yihe Sun

2011-04-01

Full Text Available Emerging green-energy transportation, such as hybrid electric vehicles (HEVs and plug-in HEVs (PHEVs, has a great potential for reduction of fuel consumption and greenhouse emissions. The lithium-ion battery system used in these vehicles, however, is bulky, expensive and unreliable, and has been the primary roadblock for transportation electrification. Meanwhile, few studies have considered user-specific driving behavior and its significant impact on (PHEV fuel efficiency, battery system lifetime, and the environment. This paper presents a detailed investigation of battery system modeling and real-world user-specific driving behavior analysis for emerging electric-drive vehicles. The proposed model is fast to compute and accurate for analyzing battery system run-time and long-term cycle life with a focus on temperature dependent battery system capacity fading and variation. The proposed solution is validated against physical measurement using real-world user driving studies, and has been adopted to facilitate battery system design and optimization. Using the collected real-world hybrid vehicle and run-time driving data, we have also conducted detailed analytical studies of users’ specific driving patterns and their impacts on hybrid vehicle electric energy and fuel efficiency. This work provides a solid foundation for future energy control with emerging electric-drive applications.

X-ray system with coupled source drive and detector drive

International Nuclear Information System (INIS)

1976-01-01

An electronic coupling replacing the (more expensive) mechanical coupling which controls the speed of two sets of two electric motors, one driving an X-ray source and the other an X-ray detector, is described. Source and detector are kept rotating in parallel planes with a fairly constant velocity ratio. The drives are controlled by an electronic system comprising a comparator circuit comparing the position-indicative signals, a process control circuit and an inverter switch. The control system regulates the speed of the electric motors. The signal processing is described

Electric Vehicle - Economical driving

DEFF Research Database (Denmark)

Jensen, VCE, Steen V.; Schøn, Henriette

1999-01-01

How do you reduce the energy-wast when driving and loading EV's - or rather: How do I get more km/l out of an EV......How do you reduce the energy-wast when driving and loading EV's - or rather: How do I get more km/l out of an EV...

Methodology for functional MRI of simulated driving.

Science.gov (United States)

Kan, Karen; Schweizer, Tom A; Tam, Fred; Graham, Simon J

2013-01-01

The developed world faces major socioeconomic and medical challenges associated with motor vehicle accidents caused by risky driving. Functional magnetic resonance imaging (fMRI) of individuals using virtual reality driving simulators may provide an important research tool to assess driving safety, based on brain activity and behavior. A fMRI-compatible driving simulator was developed and evaluated in the context of straight driving, turning, and stopping in 16 young healthy adults. Robust maps of brain activity were obtained, including activation of the primary motor cortex, cerebellum, visual cortex, and parietal lobe, with limited head motion (driving is a feasible undertaking.

A thermodynamic approach to compare the performance of rhombic-drive and crank-drive mechanisms for a beta-type Stirling engine

International Nuclear Information System (INIS)

Aksoy, F.; Solmaz, H.; Karabulut, H.; Cinar, C.; Ozgoren, Y.O.; Polat, Seyfi

2016-01-01

Highlights: • Rhombic drive and crank drive mechanisms of a beta type engine were compared. • Nodal analysis method was used to compare engines having different drive mechanism. • Maximum specific power was 1410 W/L for rhombic-drive engine. • Heat transfer coefficient was determined as 475 W/m"2K for rhombic-drive engine. • Rhombic drive provided higher efficiency because of its better kinematic behaviours. - Abstract: In this study, the effect of rhombic drive and crank drive mechanisms on the performance of a beta-type Stirling engine was investigated by nodal analysis. Kinematic and thermodynamic relations for both drive mechanisms were introduced and a Fortran code was written for the solution. Piston strokes, cylinder and displacer diameters, hot and cold end temperatures, regenerator volumes and heat transfer surface areas were taken equal for both engines with two different drive mechanisms. In the analysis, air was used as the working gas. Engine power and efficiency were compared for different charge pressure values, working gas mass values, heat transfer coefficients and hot end temperatures. Maximum specific engine power was 1410 W/L for the engine with rhombic drive mechanism and 1200 W/L for the engine with crank drive mechanism at 4 bars of charge pressure and 500 W/m"2K heat transfer coefficient. Rhombic drive mechanism was relatively advantageous at low working gas mass values and high hot end temperatures. In comparison with the engine having rhombic drive mechanism, the relatively poor kinematic behaviour of the engine having crank drive mechanism caused lower engine efficiency and performance. Heat transfer coefficient was also predicted by using an experimental pressure trace.

Driving When You Have Parkinson's Disease

Science.gov (United States)

Driving When You Have Parkinson’s Disease DRIVEWELL You have been a safe driver for years. For you, driving means freedom and control. As you get ... mental health can affect how safely you drive. Parkinson’s disease is a disorder of the central nervous ...

Cooperative driving in platooning scenario’s

NARCIS (Netherlands)

van der Linden, M.J.G.M.; Nijmeijer, H.

2011-01-01

Cooperative driving enables a more efficient use of existing infrastructure which reduces the expenditures and land use for new roads. Cooperative driving is based on intelligent communication between vehicles and between vehicles and their environment. Vehicles can drive closer to each other due to

Research of descriptions of collinear aerial receiving system ADS-B by numeral methods

Directory of Open Access Journals (Sweden)

В. П. Харченко

2013-07-01

Full Text Available Calculations of electric field intensity and directional diagrammes for colinear antennas using a method of moments in the framework of two program complexes are carried out. Comparison has shown high level of results coincidence. The sample of the antenna which is used in operating system for reception of ADS-B signals from airborne transponders is constructed

Low Power DEAP Actuator Drive for Heating Valves

DEFF Research Database (Denmark)

Huang, Lina

predict the behaviour and efficiency in both charging and discharging mode. The system level energy consumption is relatively low when the burst mode control scheme is applied. If 2.5 Ah batteries are employed, the high voltage driving system with bidirectional converter can run for around 2.1 years....... efficiency analysis has been carried out to achieve efficiency calculation model. Moreover, two system level control schemes are proposed to achieve the corresponding temperature control. The functionality and energy consumption of the high voltage driver have been verified through the test in the practical...

What Drives Private and Public Merger Waves in Europe?

DEFF Research Database (Denmark)

Bartholdy, Jan; Blunck, Benjamin

What drives merger waves? Harford 2005 argues that mergers are an efficient response to economic shocks to an industry, whereas Rhodes-Kropf, Robinson & Viswanathan 2005 argues that merger waves are driven by overvaluation of the acquiring firm, and to a lesser extent, the target firm. Both paper...... significant differences between driving forces for listed firms and for private firms. Public or listed firm mergers and acquisitions are primarily driven by overvaluation or behavioural factors, whereas private transactions are driven by economic factors.......What drives merger waves? Harford 2005 argues that mergers are an efficient response to economic shocks to an industry, whereas Rhodes-Kropf, Robinson & Viswanathan 2005 argues that merger waves are driven by overvaluation of the acquiring firm, and to a lesser extent, the target firm. Both papers...... are based on empirical analyses of listed US firms. This paper presents additional evidence of merger waves in the European Union (EU). The use of European data allows a more detailed analysis, since firm level data is available for both listed as well as private transactions. This analysis reveals...

Physiological responses to social and nonsocial stimuli in neurotypical adults with high and low levels of autistic traits: implications for understanding nonsocial drive in autism spectrum disorders.

Science.gov (United States)

Singleton, Clarence J; Ashwin, Chris; Brosnan, Mark

2014-12-01

Researchers have suggested that the two primary cognitive features of autism spectrum disorder (ASD), a drive toward nonsocial processing and a reduced drive toward social processing, may be unrelated to each other in the neurotypical (NT) population and may therefore require separate explanations. Drive toward types of processing may be related to physiological arousal to categories of stimuli, such as social (e.g., faces) or nonsocial (e.g., trains). This study investigated how autistic traits in an NT population might relate to differences in physiological responses to nonsocial compared with social stimuli. NT participants were recruited to examine these differences in those with high vs. low degrees of ASD traits. Forty-six participants (21 male, 25 female) completed the Autism Spectrum Quotient (AQ) to measure ASD traits before viewing a series of 24 images while skin conductance response (SCR) was recorded. Images included six nonsocial, six social, six face-like cartoons, and six nonsocial (relating to participants' personal interests). Analysis revealed that those with a higher AQ had significantly greater SCR arousal to nonsocial stimuli than those with a low AQ, and the higher the AQ, the greater the difference between SCR arousal to nonsocial and social stimuli. This is the first study to identify the relationship between AQ and physiological response to nonsocial stimuli, and a relationship between physiological response to both social and nonsocial stimuli, suggesting that physiological response may underlie the atypical drive toward nonsocial processing seen in ASD, and that at the physiological level at least the social and nonsocial in ASD may be related to one another. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.

ECO-DRIVING Europe - building the frame for a European market for eco-driving

International Nuclear Information System (INIS)

Raimund, Willy; Fickl, Stephan

2003-01-01

Due to rapidly increasing greenhouse gas emissions, the transport sector is a key issue in any sustainability and climate strategy. Still, it is the one most difficult to deal with because of it's complexity and direct impact on everybody's life. Innovative transport technologies can significantly contribute to reducing emissions and energy use, but there is also a need for behavioural changes to turn down energy demand, especially in individual motorised transport. One of the most cost-effective measures in this field is Ecodriving, an energy efficient and road safety improving driving style. Nowadays, there are several stand-alone initiatives in Europe. But to strengthen Ecodriving and increase its market share it needs: - an overview of existing offers and facilities, - pilot projects with different target groups, - training courses (both for novice drivers and experienced road users), - quality standards, - scientific proof of the various benefits, - awareness raising and marketing. That's why ECO-DRIVING Europe has been initiated by the main stakeholders in Europe. It aims to change the behaviour of drivers by using technological developments, influencing legislation and supporting long term driving and mobility culture change. The Europe-wide ECO-DRIVING project (www.ecodrive.org ) tries to reach this goal by integrating Ecodriving into various policy fields such as energy, climate change, road safety, local environment, sustainable transport and legislation for driver licence procedures. By decreasing greenhouse gas emission by 10-20% compared to normal driving, Ecodriving can considerably contribute to reduce energy demand in transport and fight climate change. Keywords ECO-DRIVING, sustainable transport, energy efficiency, behavioural change, market penetration, environmental and economic benefits, road safety

Potential determinants of drink driving in young adults.

Science.gov (United States)

González-Iglesias, Beatriz; Gómez-Fraguela, José António; Sobral, Jorge

2015-01-01

The main purposes of this study were to examine the usefulness of the variables of the theory of planned behavior (viz. attitudes, social norms, and self-efficacy) and to explore the relationship between optimism bias and drink driving in young adults. In addition, we explored gender differences in drink driving with provision for the effect of variables such as driving frequency and alcohol consumption. Data were collected via a questionnaire administered to 274 drivers (59.9% females) aged 18-30 years (24.36 ± 2.96). The results obtained with provision for driving frequency revealed substantial differences in driving behaviors between genders. Thus, males were more prone to drink driving, perceived less disapproval by their significant others (parents and peers), and felt less able to avoid drinking-and-driving situations. In addition, they self-reported more frequent alcohol consumption and driving under the influence. The results also confirm the significance of peers' subjective norms and attitudes to drink driving in males. Overconfidence in their own driving skills for driving drunk and perceived behavioral control were found to be significant predictors for drink driving in females. Optimism bias also played a slightly significant role in predicting drink driving but only in females. The important practical implications of these results with a view to designing effective interventions to prevent the risks associated with drink driving in the young population are discussed. Interventions should focus on young people's perceptions of group norms and promoting cautionary driving choices and alternatives to drink driving.

BP's driving safety strategy

Energy Technology Data Exchange (ETDEWEB)

Herman, B. [BP Canada Energy Company, Calgary, AB (Canada)

2006-07-01

This presentation focused on why it is important to drive safely. It addressed driver fatigue as well as BP's global driving standard. The Standard applies to all BP employees and contractors that drive any vehicle on BP business and consists of 10 mandatory elements focusing on safety of the driver, the safety of the journey, and the safety of the vehicle. The driving standards focus on several themes, including skill and competency of the driver, safety of the journey, and safety of the vehicle. Fatigue causes more than 20 per cent of motorway accidents and is the most frequent cause of accidental death of truck drivers. The presentation also discussed vehicle data recorders, driving immersion, and Driving Safety Program results. Journey management, driver training, vehicle inspections and policies, and statistics on vehicle incidents were also provided. The presentation revealed that a lack of pre-trip journey management, inadequate training or recall of training, and not following safe driving practices were major contributors to incident occurrences. It also revealed that traveling on gravel or ice and avoiding wildlife were factors in many vehicle incidents. 1 tab., 1 fig.

Greater Sudbury fuel efficient driving handbook

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-12-15

Reducing the amount of fuel that people use for personal driving saves money, improves local air quality, and reduces personal contributions to climate change. This handbook was developed to be used as a tool for a fuel efficient driving pilot program in Greater Sudbury in 2009-2010. Specifically, the purpose of the handbook was to provide greater Sudbury drivers with information on how to drive and maintain their personal vehicles in order to maximize fuel efficiency. The handbook also provides tips for purchasing fuel efficient vehicles. It outlines the benefits of fuel maximization, with particular reference to reducing contributions to climate change; reducing emissions of air pollutants; safe driving; and money savings. Some tips for efficient driving are to avoid aggressive driving; use cruise control; plan trips; and remove excess weight. Tips for efficient winter driving are to avoid idling to warm up the engine; use a block heater; remove snow and ice; use snow tires; and check tire pressure. The importance of car maintenance and tire pressure was emphasized. The handbook also explains how fuel consumption ratings are developed by vehicle manufacturers. refs., figs.

Configuring NIF for direct drive experiments

International Nuclear Information System (INIS)

Eimerl, D.; Rothenberg, J.; Key, M.

1995-01-01

The National Ignition Facility (NIF) is a proposed 1.8 MJ laser facility for carrying out experiments in inertial confinement fusion, currently designed for indirect drive experiments. The direct drive approach is being pursued at the 30 kJ Omega facility at the University of Rochester. In this paper we discuss the modifications to the NIF laser that would be required for both indirect and direct drive experiments. A primary concern is the additional cost of adding direct drive capability to the facility

Non-inductive current drive experiments on DIII-D, and future plans

International Nuclear Information System (INIS)

Prater, R.; Austin, M.; Baity, F.W.; Callis, R.W.; Chiu, S.C.; DeGrassie, J.S.; Freeman, R.L.; Forest, C.B.; Goulding, R.H.; Harvey, R.W.; Hoffman, D.J.; Ikezi, H.; Lohr, J.; James, R.A.; Kupfer, K.; Lin-Liu, Y.R.; Luce, T.C.; Moeller, C.P.; Petty, C.C.; Pinsker, R.I.; Porkolab, M.; Squire, J.; Trukhin, V.

1995-01-01

Experiments on DIII-D (and other tokamaks) have shown that improved performance can follow from optimization of the current density profile. Increased confinement of energy and a higher limit on β have both been found in discharges in which the current density profile is modified through transient means, such as ramping of current or elongation. Peaking of the current distribution to obtain discharges with high internal inductance l i has been found to be beneficial. Alternatively, discharges with broader profiles, as in the VH mode or with high β poloidal, have shown improved performance. Non-inductive current drive is a means to access these modes of improved confinement on a steady state basis. Accordingly, experiments on non-inductive current drive are underway on the DIII-D tokamak using fast waves and electron cyclotron waves. Recent experiments on fast wave current drive have demonstrated the ability to drive up to 180kA of non-inductive current using 1.5MW of power at 60MHz, including the contribution from 1MW of ECCD and the bootstrap current. Higher power r.f. current drive systems are needed to affect strongly the current profile on DIII-D. An upgrade to the fast wave current drive system is underway to increase the total power to 6MW, using two additional antennas and two new 30-120MHz transmitters. Additionally, a 1MW prototype ECH system at 110GHz is being developed (with eventual upgrade to 10MW). With these systems, non-inductive current drive at the 1MA level will be available for experiments on profile control in DIII-D. ((orig.))

Distracted Driving, A Major Preventable Cause of Motor Vehicle Collisions: "Just Hang Up and Drive".

Science.gov (United States)

Kahn, Christopher A; Cisneros, Victor; Lotfipour, Shahram; Imani, Ghasem; Chakravarthy, Bharath

2015-12-01

For years, public health experts have been concerned about the effect of cell phone use on motor vehicle collisions, part of a phenomenon known as "distracted driving." The Morbidity and Mortality Weekly Report (MMWR) article "Mobile Device Use While Driving - United States and Seven European Countries 2011" highlights the international nature of these concerns. Recent (2011) estimates from the National Highway Traffic Safety Administration are that 10% of fatal crashes and 17% of injury crashes were reported as distraction-affected. Of 3,331 people killed in 2011 on roadways in the U.S. as a result of driver distraction, 385 died in a crash where at least one driver was using a cell phone. For drivers 15-19 years old involved in a fatal crash, 21% of the distracted drivers were distracted by the use of cell phones. Efforts to reduce cell phone use while driving could reduce the prevalence of automobile crashes related to distracted driving. The MMWR report shows that there is much ground to cover with distracted driving. Emergency physicians frequently see the devastating effects of distracted driving on a daily basis and should take a more active role on sharing the information with patients, administrators, legislators, friends and family.

Full drive-by-wire dynamic control for four-wheel-steer all-wheel-drive vehicles

Science.gov (United States)

Fahimi, Farbod

2013-03-01

Most of the controllers introduced for four-wheel-steer (4WS) vehicles are derived with the assumption that the longitudinal speed of the vehicle is constant. However, in real applications, the longitudinal speed varies, and the longitudinal, lateral, and yaw dynamics are coupled. In this paper, the longitudinal dynamics of the vehicle as well as its lateral and yaw motions are controlled simultaneously. This way, the effect of driving/braking forces of the tires on the lateral and yaw motions of the vehicle are automatically included in the control laws. To address the dynamic parameter uncertainty of the vehicle, a chatter-free variable structure controller is introduced. Elimination of chatter is achieved by introducing a dynamically adaptive boundary layer thickness. It is shown via simulations that the proposed control approach performs more robustly than the controllers developed based on dynamic models, in which longitudinal speed is assumed to be constant, and only lateral speed and yaw rate are used as system states. Furthermore, this approach supports all-wheel-drive vehicles. Front-wheel-drive or rear-wheel-drive vehicles are also supported as special cases of an all-wheel-drive vehicle.