Driver Frequency Research Articles

Driver irritation and aggressive behaviour

A sample of 98 drivers responded to a Swedish version of the UK Driving Anger Scale [UK DAS; [Lajunen, T., Parker, D., Stradling, S.G., 1998. Dimensions of driver anger, aggressive and highway code violations and their mediation by safety orientation in UK drivers. Transport. Res. Part F 1, 107–121]. The results indicated that the Swedish version, like the British original, measures three sources of driver irritation: “progress impeded”, “reckless driving”, and “direct hostility”. Structural equation modelling was used to investigate the relationships between the three sources of self-reported driver irritation, aggressive actions, speed, sex, age, and annual mileage. The models suggested a positive relationship between the amount of driver irritation and frequency of aggressive actions for all three sources of irritation. Female drivers tended to become more irritated than male drivers, while the male drivers tended to act aggressively more often. Surprisingly, drivers who reported that they enjoy fast speeds did not become more irritated than slower drivers when obstructed. The important conclusions are that experienced irritation often leads to openly aggressively actions, and that expression of aggressive behaviours may be a cause of other drivers’ feeling of irritation.

Driven intrinsic localized modes in a coupled pendulum array

Intrinsic localized modes (ILMs), also called discrete breathers, are directly generated via modulational instability in an array of coupled pendulums. These ILMs can be stabilized over a range of driver frequencies and amplitudes. They are characterized by a π-phase difference between their centre and wings. At higher driver frequencies, these ILMs are observed to disintegrate via a pulsating instability, and the mechanism of this breather instability is investigated.

Frequency, determinants, and consequences of different drivers’ emotions: An on-the-road study using self-reports, (observed) behaviour, and physiology

In the present study, the frequency, determinants and consequences of three relevant emotions in traffic were investigated. Based on appraisal theory, it was predicted that the combination of three appraisal components (goal congruence, blame and threat) affects the occurrence of anger, anxiety and happiness. Participants (n = 44) filled in a questionnaire containing background and personality variables, and performed a test drive in an instrumented car. During the drive, speed and heart rate were registered and the traffic environment was recorded on video. Participants verbally reported scores for emotions and perceived risk. The most frequently occurring emotion was anxiety, followed by anger and happiness. Emotions while driving were related to emotional traits. Emotions while driving were also related to traffic events: anger and anxiety were both associated with goal incongruent events, and happiness with goal congruent events. Anger was mostly associated with other-blame and anxiety with situation-blame. Anger was mostly associated with events affecting impeded progress, and anxiety with events affecting safety. Anxiety, but not anger or happiness, was associated with increased perceived risk and with increased heart rate. Participants who reported anger drove faster and exceeded the speed limit more often on a 100 km/road section than participants who did not report anger. These and other results are discussed in terms of appraisal theory and state-trait differences in emotion.

Vlasov models for the study of stimulated Raman scattering and beatwave acceleration scenario

Relativistic Vlasov–Maxwell model was developed to address the particle trapping or particle acceleration in phase space, including situation relevant to Stimulated Raman Scattering and plasma beatwave acceleration. In particular the case of realistically high ratio of driver frequency to plasma wave frequency ( ω 0 / ω p ∼ 30 ) was also considered using a hybrid version called Vlasov–Hilbert model. Some of the more striking features that have emerged from the Vlasov simulations are discussed in this paper, with particular emphasis on time-dependent matching relations in frequency and wavevector allowing the maintenance of the parametric resonance over a long time, particle dynamics in phase space and action transfer results obtained from the derivation of the integrated Manley–Rowe relations derived for a finite causal system.

A simple and cost-effective high voltage radio frequency driver for multipolar ion guides

Multipolar RF ion traps are widely used in mass spectrometry for guiding ion beams and are fundamental tools to study ion–molecule reactions in the near thermal and sub-thermal regime. A flexible, cheap and reliable RF power source can be obtained by using a home-made matching network to couple the ion guide to a commercial RF power supply. In this paper we describe the design and the construction of a RF power supply for driving two octopole ion guides at the same time. Details on the design and the practical building of the matching network are discussed. Performances of the apparatus are demonstrated by measuring transmission curves for Helium, Neon and Argon ions.

Can Mapping and Ablation of Atrial Fibrillation Be Guided by Frequency Analysis of Fibrillatory Waves?

Conventional atrial fibrillation (AF) mapping is limited by the interpretation of the varied and complex time‐domain signals throughout the atria. Frequency‐domain signals provide a feasible method to analyze the temporal and regional distribution of atrial activation during AF. This helps us learn more about the mechanisms of AF. The maintenance of AF, whether paroxysmal or persistent, depends on rapid activities in part of the atrium. These AF sources activate atria at very high frequencies and result in fibrillatory conductions. This article focuses on the regional frequency distribution and the spectral morphology in different types of AF. In patients with paroxysmal AF from pulmonary veins, the highest frequency drivers are located around the arrhythmogenic vein with a left atrium (LA)‐to‐right atrium (RA) frequency gradient. Conversely, in patients with paroxysmal AF from superior vena cava and persistent AF, the LA‐to‐RA frequency gradient may not be evident. As the figure demonstrates, the ablation strategy guided by frequency analysis may be a better way for finding the critical substrate for the maintenance of AF.

The stepwise ablation approach for chronic atrial fibrillation—Evidence for a cumulative effect

Treatment options for atrial fibrillation (AF) have evolved from simple, fluoroscopy-guided pulmonary vein isolation for those patients with paroxysmal AF to complex, multi-modality procedures targeting not only anatomic structures but also electrophysiologic phenomena including complex fractionated electrograms, sites of dominant frequency and local non-venous drivers in patients with persistent and permanent AF. The stepwise ablation approach is a novel technique whereby structures contributing to initiation and maintenance of AF are sequentially targeted by radiofrequency ablation. Broadly divided into pulmonary veins, left atrial (LA) roof, left atrium (incorporating all anatomic regions of the chamber), mitral isthmus and non-LA structures, each region is targeted in sequence and the impact of ablation upon the global fibrillatory process assessed by measurement of AF cycle length (AFCL) at a site remote from the ablation target. In addition to pulmonary vein electrical disconnection and demonstrable complete conduction block across the roof and mitral isthmus lines (when performed), ablation is performed at those sites displaying continuous electrical and complex fractionated activity, with the endpoint of local organization, as well as at sites displaying electrograms consistent with focal sources driving AF. Ablation is accompanied by a cumulative increase in the AFCL prior to termination of AF by conversion either directly to sinus rhythm or to an atrial tachycardia which is then mapped conventionally and ablated. There is a ceiling of ablation within the LA beyond which further ablation is unlikely to result in a clinical benefit and should prompt evaluation of the contribution of the right atrium to maintenance of AF. The stepwise approach benefits from the integration of anatomic and electrophysiologic information to achieve a high level of success in termination of chronic AF by catheter ablation.

Activation of Inward Rectifier Potassium Channels Accelerates Atrial Fibrillation in Humans

It is unclear whether atrial fibrillation (AF) drivers in humans are focal or reentrant. To test the hypothesis that functional reentry is involved in human AF maintenance, we determined the effects of adenosine infusion on local dominant frequency (DF) at different atrial sites. By increasing inward rectifier potassium channel conductance, adenosine would increase DF of reentrant drivers but decrease it in the case of a focal mechanism. Thirty-three patients were studied during AF (21 paroxysmal, 12 persistent) using recordings from each pulmonary vein-left atrial junction (PV-LAJ), high right atrium, and coronary sinus. DFs were determined during baseline and peak adenosine effect. In paroxysmal AF, adenosine increased maximal DF at each region compared with baseline (PV-LAJ, 8.03+/-2.2 versus 5.7+/-0.8; high right atrium, 7+/-2.2 versus 5.4+/-0.7; coronary sinus, 6.6+/-1.1 versus 5.3+/-0.7 Hz; P=0.001) and increased the left-to-right DF gradient (P=0.007). In contrast, in persistent AF, adenosine increased DF only in the high right atrium (8.33+/-1.1 versus 6.8+/-1.2 Hz; P=0.004). In 4 paroxysmal AF patients, real-time DF mapping of the left atrium identified the highest DF sites near the PV-LAJ, where adenosine induced an increase in DF (6.7+/-0.29 versus 4.96+/-0.26 Hz; P=0.008). Finally, simulations demonstrate that the frequency of reentrant drivers accelerates proportionally to the adenosine-modulated inward rectifier potassium current. Adenosine accelerates drivers and increases frequency differently in paroxysmal compared with persistent human AF. The results strongly suggest that AF is maintained by reentrant sources, most likely located at the PV-LAJ in paroxysmal AF, whereas non-PV locations are more likely in persistent AF.

Effects of implementation intentions on the self-reported frequency of drivers' compliance with speed limits.

This study tested the efficacy of implementation intentions in the context of drivers' speeding behavior. Participants (N = 300) completed self-report measures of goal intention and behavior, and they were randomly assigned to an experimental condition, which required them to specify an implementation intention, or a control condition. One month post-baseline, self-reported compliance with speed limits significantly increased for experimental participants but not for control participants. The effects of specifying an implementation intention on behavior increased with the strength of drivers' goal intentions. Finally, analysis of participants' implementation intentions revealed that specifying more behavioral strategies increased the frequency with which participants reported complying with the speed limit. Implications of the findings are discussed in relation to enhancing road safety interventions.

System for detecting failures in a loudspeaker assembly

This invention is directed to a system and method for isolating a failure in a speaker system. This is accomplished by providing diagnostic processing circuitry, which directs specific test signal(s) to the speakers of a speaker system. The test signals may be designed to allow a user to directionally localize a sound source to determine if a particular speaker is functional. The test signals also may be designed so a user or listener may distinguish sound emanating from a low frequency driver such as a subwoofer versus other speakers. The diagnostic processing circuitry may be located in any of the individual speakers or other common components of a speaker system.

A Study on Vehicle-to-vehicle Accidents in Intergreen Periods

Using the data of ITARDA Micro Accidents' Research, vehicle-to-vehicle accidents in intergreen periods were analysed. Thirty percent of Vehicle-to-vehicle accidents occurred in intergreen periods at signalized intersection, intergreen periods were hazardous. Angle accidents occurred more in intergreen periods. More drivers that cause vehicle-to-vehicle accidents in intergreen periods recognized hazard. Analyzing by attribute, heavy vehicle, man, elder and high frequency drivers cause vehicle-to-vehicle accidents in intergreen periods more.

Use of Fast Fourier Transform Analysis of Atrial Electrograms for Rapid Characterization of Atrial Activation—Implications for Delineating Possible Mechanisms of Atrial Tachyarrhythmias

Different analysis techniques have been developed to help understand and characterize the mechanisms responsible for atrial arrhythmias. We tested the hypothesis that Fast Fourier Transform (FFT) analysis of recorded atrial electrograms (AEGs) will rapidly and accurately identify regular and irregular patterns of atrial activation, and, thereby, may provide evidence suggestive of underlying mechanisms of atrial tachyarrhythmias. During induced atrial tachyarrhythmias in both the canine sterile pericarditis model and canine rapid ventricular pacing-induced congestive heart failure model; 380-404 AEGs were recorded simultaneously from epicardial electrodes on both atria. From AEGs, atrial activation sequences were determined during atrial flutter (AFL), focal atrial tachycardia (AT), and atrial fibrillation (AF). Four-second recording segments of each AEG were subjected to FFT analysis. Frequencies found during FFT analyses in all studies precisely corresponded to the cycle lengths of the AEGs. In AFL and AT, one dominant frequency peak was found throughout both atria. In AF due to multiple unstable reentry circuits, multiple and broad frequency peaks were found in both atria. In AF due to a stable rapid rhythm (driver) in the left atrium with fibrillatory conduction to the rest of the atria, one dominant frequency peak in areas with 1:1 conduction from the driver, and multiple and/or broad frequency peaks in areas with fibrillatory conduction produced by the driver were found. Computation time for all FFT analyses took <5 minutes. FFT analysis accurately and rapidly identifies global atrial activation patterns during AFL, AT, and AF, thereby assisting in determining arrhythmia mechanisms.

Analysis of frequency divider RTD circuits

The behavior of a novel circuit topology able to implement a frequency divider is studied. This circuit is composed of a resonant tunnelling diode (RTD), an inductor, and a capacitor, so it exhibits a very high operating frequency and low power consumption. It employs the period-adding sequences which appear in its bifurcation diagram to perform the frequency division. Compared to a previously reported similar circuit, it has wider operation windows and a higher division factor for the driver frequency, while maintaining the extremely high operating frequency, its simplicity, and the division factor tunability through the selection of circuit parameters. Simulation results using the HSPICE RTD model from project LOCOM as well as several realistic parasitics elements are given, which confirm the theoretical capabilities previously analyzed.

Parametric instability of a driven ion-acoustic wave

The stability of a driven coherent ion-acoustic wave (IAW) with regard to its decay into longer wavelengths is investigated. The effects of harmonic generation and wave dispersion are taken into account. The driver frequency and wave number do not necessarily satisfy the linear ion-acoustic wave dispersion relation, allowing a frequency mismatch between the driver frequency and the plasma linear-response frequency. The stability analysis is generally shown to involve a seven wave coupling in which the fundamental and the second-harmonic components of the equilibrium IAW couple to a low-frequency daughter wave and to their Stokes and anti-Stokes satellites. The general dispersion relation corresponding to this seven wave coupling is derived and solved numerically in three-dimensional geometry. A variety of branches of instabilities is found to appear. In order to classify these branches, an approximate dispersion relation is derived, corresponding to the Korteweg–de-Vries limit for the plasma low-frequency nonlinear behavior. This approximate dispersion relation makes it possible to obtain approximate expressions for the growth rate of each branch. The occurrence of each type of instability is discussed as a function of the sign and size of the frequency mismatch. The special case of one-dimensional geometry is also considered, making it possible to investigate the results of one-dimensional numerical simulations.

Counting discrete emission steps from intrinsic localized modes in a quasi-one-dimensional antiferromagnetic lattice

Intrinsic localized modes (ILMs) in a quasi-1D antiferromagnetic material ${({\mathrm{C}}_{2}{\mathrm{H}}_{5}\mathrm{N}{\mathrm{H}}_{3})}_{2}\mathrm{Cu}{\mathrm{Cl}}_{4}$ are counted by using a novel nonlinear energy magnetometer. The ILMs are produced by driving the uniform spin wave mode unstable with an intense microwave pulse. Subsequently a subset of these ILMs become captured by and locked to a cw driver so that their properties can be examined at a later time with a tunable cw low power probe source. Four-wave mixing is used to enhance the emission signal from the few large amplitude ILMs over that associated with the many small amplitude plane wave modes. A discrete step structure observed in the emission signal is identified with individual ILMs becoming unlocked from the driver. At most driver power and frequency settings the resulting emission step structure appears uniformly distributed; however, sometimes, nearby in parameter space, families of emission steps are evident as the driver frequency or power is varied. Two different experimental methods give consistent results for counting individual ILMs. Because of the discreteness in the emission both the size of an ILM and its energy can be estimated from these experiments. For the uniformly distributed case each ILM extends over $\ensuremath{\sim}42$ antiferromagnetic unit cells and has an energy value of $1.3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}\phantom{\rule{0.3em}{0ex}}\mathrm{J}$ while for the case with families the ILM length becomes $\ensuremath{\sim}54$ antiferromagnetic unit cells with an energy of $1.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}\phantom{\rule{0.3em}{0ex}}\mathrm{J}$. An unresolved puzzle is that the emission step height does not depend on experimental parameters the way classical numerical simulations suggest.

Credit-based congestion pricing: a policy proposal and the public’s response

Credit-based congestion pricing (CBCP) is a novel strategy proposed here. A revenue-neutral policy where road tolls are based on the negative externalities associated with driving under congested conditions, its generated tolls are returned to all licensed drivers in a uniform fashion, as a sort of driving “allowance”. Essentially, the “average” driver pays nothing, while frequent long-distance peak-period drivers subsidize others, in effect paying them to stay off congested roads. In order to anticipate initial public response to a CBCP policy, 500 individuals completed a detailed survey regarding perceptions of, and likely travel reactions to, such a policy. Weights were developed to correct for survey biases in gender, age and household income. Analytical results suggest that 25% support this new strategy, and support is strongly related to familiarity with the concept of congestion pricing. Respondent estimates of congested travel times to work or school are almost double the uncongested times. Values of travel time vary greatly across respondents, as also trip flexibility. Those without children, younger respondents, and those with fewer vehicles appear more willing to support such a policy and more likely to modify their travel behaviors. Older people and full time employed people were willing to pay higher CBCP tolls to drive during peak hours and so were men as compared to women. The survey results corroborate the potential of a CBCP policy to alleviate congestion and generate benefits across income groups and traveler types.

Lessons from a PV pumping programme in south Morocco

This paper presents the experience of a PV pumping project being carried-out in the South of Morocco since 1997. At present, the project has reached 18 villages, affecting 15 000 people. Total involved photovoltaic power is 46 kWp, and the total volume of pumped water since the installation of the systems approaches 0.7 × 106 m3. About half the PV systems are based on dedicated inverters, while the rest are based on standard frequency drivers. Both perform very similarly in terms of both efficiency and reliability. Wells have been selected to provide good water taste, and pumped water is distributed to all the individual houses. Average daily water consumption in summer varies from 13 to 50 litres per person depending on ease of water access and ‚urban proximity’. The maintenance infrastructure is based on an agreement between the European supplier company and a local NGO, which is in charge of all the local organizations. Copyright © 2005 John Wiley & Sons, Ltd.

Car use: lust and must. Instrumental, symbolic and affective motives for car use

This paper reports results of two questionnaire studies aimed at examining various motives for car use. In the first study, a random selection of 185 respondents who possess a driving licence were interviewed. Respondents were recruited from the cities of Groningen and Rotterdam, The Netherlands. The sample of the second study comprised a random selection of 113 commuters who regularly travelled during rush hours in and around Rotterdam, a region in the west of the Netherlands. First, it was examined which categories of car use motives may be distinguished. As proposed by Dittmar’s (1992) [The social psychology of material possessions: to have is to be. Havester Wheatsheaf, Hemel Hempstead, UK; St. Martin’s Press, New York] model on the meaning of material possessions, results from both studies revealed that car use not only fulfils instrumental functions, but also important symbolic and affective functions. Second, it was studied to what extent these different motives are related to the level of car use. From the results of study 2, it appeared that commuter car use was most strongly related to symbolic and affective motives, and not to instrumental motives. Third, individual differences in the relative importance of the three categories of motives were investigated. In both studies, most group differences were found in the evaluation of the symbolic and affective motives (and not the instrumental ones). Especially frequent drivers, respondents with a positive car attitude, male and younger respondents valued these non-instrumental motives for car use. These results suggest that policy makers should not exclusively focus on instrumental motives for car use, but they should consider the many social and affective motives as well.

Les politiques d'accompagnement du péage urbain : étude sur l'acceptabilité en Suisse

Résumé Le présent document s’intéresse à l’épineuse question de l’acceptabilité du péage de congestion et aux politiques d’accompagnement à envisager pour le rendre plus acceptable aux yeux des citoyens. À partir d’une enquête récente réalisée en Suisse Romande, on effectue une analyse des correspondances multiples à l’aide du logiciel de traitement de données SPAD afin de regrouper des individus autour de différentes modalités (utilisation de la voiture, perception du péage, affectation des recettes du péage...). L’étude des graphiques fait ressortir plusieurs groupes dont deux fortement opposés : les automobilistes fréquents et les automobilistes occasionnels.

Loudspeaker array for enlarged sweet spot

The invention is a method of creating an enlarged listening sweet spot for multiloudspeaker audio reproduction. The method employs a plurality of audio drivers (52, 56) displaced generally in a horizontal dimension for a vertically oriented head of a listener (60), the drivers operating over a plurality of different passbands (42, 46). Higher frequency drivers (55, 59) are located closer to one another and displaced more towards a center line of the listening space than lower frequency drivers (53, 57), thereby causing a smaller change in acoustic ear signals for listeners (60) seated away from the designed-for listening position, but without causing increased low frequency signal capacity requirements for phantom images generally outside the array (50). Specially adapted signal processing accounting for the layout of the various drivers and their associated crossover networks (40) is employed to create desired audio images.