Timing of early warning stages in a multi stage collision warning system: Drivers’ evaluation depending on situational influences

By means of car2x communication technologies (car2x) driver warnings can be presented to drivers quite early. However, due to their early timing they could be misunderstood by drivers, distract or even disturb them. These problems arise if, at the moment of the warning, the safety–critical situation is not yet perceivable or critical. In order to examine, when drivers want to receive early warnings as a function of the situation criticality, a driving simulator study was conducted using the two early warning stages of a multi stage collision warning system (first stage: informing the driver; second stage: prewarning the driver). The optimum timing to activate these two early warning stages was derived by examining the drivers’ evaluation of these timings concerning their appropriateness and usefulness. As situational variation, drivers traveling at about 100 km/h were confronted with slow moving traffic either driving at 25 km/h or 50 km/h at the end of a rural road.In total, 24 participants were tested in a within-subjects design (12 female, 12 male; M = 26.6 years, SD = 7.2 years). For both stages, drivers preferred an earlier timing when approaching slow moving traffic traveling at 25 km/h (first stage: 447 m, second stage: 249 m ahead of the lead vehicle) compared to 50 km/h (first stage: 338 m, second stage: 186 m ahead of the lead vehicle). The drivers’ usefulness rating also varied with the timing, spanning a range of 8 s for driver-accepted timing variations and showed correspondence to the drivers’ appropriateness ratings. Based on these results and those of a previous study, a timing function for each of the two early warning stages depending on the speed difference between the safety–critical object and the host vehicle is presented. Indirectly, similar adaptations are already implemented in current collision warning systems, which use the time-to-collision to give drivers acute warnings in a later stage, when an immediate reaction of the driver may still prevent a collision. However, this study showed that drivers also favor this kind of adaptation for earlier warning stages (information and prewarning). Thus, adapting the timing according to the drivers’ preferences will contribute to a better acceptance of these collision warning systems.     

Social and motivational predictors of continued youth sport participation

ObjectivesThe purpose of this study was to examine if youth soccer players' perceived relationships with parents and peers in soccer, and the moderating associations among these social relationship variables, predict soccer continuation over and above motivation-related variables.DesignThis study used a prospective design by assessing youth soccer athletes' social relationships and motivational outcomes during one season and tracking the athletes' soccer continuation behavior one year later.MethodsContinuation behavior of travel soccer athletes (N = 148), ages 10–14 years (M = 11.7, SD = 1.0), was assessed one year after completing a questionnaire containing soccer-contextualized measures of perceived parent relationship quality, perceived friendship quality, perceived peer acceptance, perceived competence, enjoyment, stress, and self-determined motivation.ResultsLogistic regression analyses showed that greater perceived competence, more positive friendship quality, and the combination of mother relationship quality and peer relationships predict soccer continuation on the same team.ConclusionsThe findings highlight the importance of close social relationships, and the combination of parent and peer relationships in particular, to sport continuation behavior.     

Through babies’ eyes: Practical and theoretical considerations of using wearable technology to measure parent–infant behaviour from the mothers’ and infants’ view points

AimsTo explore the utility of first-person viewpoint cameras at home, for recording mother and infant behaviour, and for reducing problems associated with participant reactivity, which represent a fundamental bias in observational research.MethodsWe compared footage recording the same play interactions from a traditional third-person point of view (3rd PC) and using cameras worn on headbands (first-person cameras [1st PCs]) to record first-person points of view of mother and infant simultaneously. In addition, we left the dyads alone with the 1st PCs for a number of days to record natural mother–child behaviour at home. Fifteen mothers with infants (3–12 months of age) provided a total of 14 h of footage at home alone with the 1st PCs.ResultsCodings of maternal behaviour from footage of the same scenario captured from 1st PCs and 3rd PCs showed high concordance (kappa >0.8). Footage captured by the 1st PCs also showed strong inter-rater reliability (kappa = 0.9). Data from 1st PCs during sessions recorded alone at home captured more ‘negative’ maternal behaviours per min than observations using 1st PCs whilst a researcher was present (mean difference = 0.90 (95% CI 0.5–1.2, p < 0.001 representing 1.5 SDs).Conclusion1st PCs offer a number of practical advantages and can reliably record maternal and infant behaviour. This approach can also record a higher frequency of less socially desirable maternal behaviours. It is unclear whether this difference is due to lack of need of the presence of researcher or the increased duration of recordings. This finding is potentially important for research questions aiming to capture more ecologically valid behaviours and reduce demand characteristics.     

Responses to visual,tactile and visual–tactile forward collision warnings while gaze on and off the road

The objective of the current driving simulator study (N = 20) was to assess brake reaction time (BRT) and subjective experiences of visual (V), tactile (T), and visual–tactile (VT) collision warnings when the drivers’ visual orientation was manipulated between four locations (i.e., road and three different mirror locations). V warning was a blinking light in a windscreen, T warning was implemented by a vibrating accelerator pedal, and VT warning was their synchronous combination. The results showed that all the warning stimuli were detected in 100% accuracy in all visual orientations, but T and VT warnings produced significantly faster BRTs when compared to V warning. It was found that BRT to V warning was the slowest while observing the furthermost side mirror. However, BRTs following T and VT warnings remained unaffected by the visual orientations. Both the objective BRT measurements and subjective evaluations indicated a superiority of T and VT warnings against a sole V warning, not only in general terms, but also separately for different visual orientations.     

Stereotype endorsement and perceived ability as mediators of the girls' gender orientation–soccer performance relationship

ObjectiveThis study investigated girls' endorsement of the stereotype that girls are not good soccer performers through three questions: (1) did stereotype endorsement predict soccer performance? (2) Was this relationship mediated by perceived ability? (3) Was stereotype endorsement related to gender role orientation?MethodOne hundred and two junior high school girls from the 6th to the 9th grade (M age = 13.5 years, SD = 1.23) reported their beliefs about girls' and boys' performance in soccer, perceived ability and gender role orientation. Next, their soccer performance was observed during matches in compulsory physical education classes. A path-analytic model tested the relationships among the variables using a product-moment correlation matrix and a maximum likelihood estimation procedure.ResultsStereotype endorsement (i.e., the belief that girls' performance in soccer is poor) negatively predicted performance, this relationship being mediated by perceived ability. Moreover, masculinity positively predicted perceived ability, and this relationship was partially mediated by stereotype endorsement.ConclusionThis study reinforces the idea that girls' sports performance may be related to gender stereotypes. Interpretations of the results in light of Eccles et al.’s expectancy-value model and stereotype threat theory are discussed, along with implications for practice.     

Effect of an intensified training period on well-being indices,recovery and psychological aspects in professional soccer players

IntroductionIntensified training periods (IT) are associated with fatigue increase and psychological variations.ObjectiveThis investigation aimed to examine the perceived well-being, recovery quality and psychological responses during an IT.MethodsFifteen professional soccer players (mean ± SD: age: 24 ± 1 years, body mass: 71.3 ± 15.1 kg, height: 178.0 ± 6.1 cm) completed a 6-week training program consisting of 2 weeks of basic training (BT) and 4 weeks of IT. They were tested before (T1) and after (T2) the IT. Training load (TL) perception, strain and monotony were measured by the session-RPE method. Well-being indices (sleep quality, fatigue level, stress and delayed-onset muscular soreness [DOMS]) and total quality recovery (TQR) were recorded before each training session. The profile of mood states (POMS) and the Ottowa mental skills assessment tool (OMSAT)-3 were conducted before and after IT.ResultsNo significant difference was found after IT in OMSAT-3 scores (p > 0.05). TL, monotony and strain increased during IT (p < 0.001). Moreover, well-being indices (stress, sleep quality, fatigue level and DOMS) increased (p < 0.001) and TQR decreased (p < 0.001) during IT. The IT increased total mood disturbance (TMD, p < 0.001), tension (p < 0.05) and fatigue (p < 0.01) and decreased vigor (p < 0.001). Significant relationships were found between TL and Hooper Index (HI), TQR and TMD (r = 0.58, 0.65, −0.57, respectively; all p < 0.05).ConclusionThe findings of this investigation suggested that mental ability was not sensitive to fatigue caused by training load intensification. However, perceived well-being, recovery state and mood were found to be sensitive measures and may provide coaches with information about wellness and psychological state of soccer players during IT.     

Factors influencing drivers’ reading and comprehension of on-board traffic messages

IntroductionWhen variable message signs (VMS) or on-board traffic information systems are used, it is essential that while driving, motorists read and understand the information as soon as possible in order to make appropriate decisions to increase road safety and/or facilitate traffic flow. Thus, it is important to investigate the factors that may increase fast reading and comprehension of on-board traffic information.ObjectivesWe examined the influence of the type of message (warnings vs. recommendations), location of the pictogram (top or bottom of the text), type of display device (IPhone, Blackberry, or Tablet) and its position (horizontal or vertical) on drivers’ fast reading and comprehension of on-board messages provided via in-vehicle system. Moreover, we were interested in drivers’ acceptability of in-vehicle system.MethodForty-nine drivers (M_Men = 32, 19–65 years) participated to a reading and comprehension task while travelling on a desktop driving simulator. Participants were exposed to two series of 11 traffic messages displayed on one of the three devices. Reading and comprehension times were measured (= milliseconds) for each message. At the end, they had to fill in a questionnaire on their beliefs about on-board traffic messages and in-vehicle system.ResultsDrivers expressed a positive attitude toward on-board traffic messages and in-vehicle system. Reading and comprehension times were of approximately 4 seconds and were longer for warnings as compared to recommendations. The pictogram placed at the top of the text, the tablet and the vertical display device facilitated fast reading and comprehension.     

Relationships between match activities and peak power output and Creatine Kinase responses to professional reserve team soccer match-play

The specific movement demands of soccer that are linked to post-match recovery and readiness to train are unclear. Therefore, we examined the relationship between Global Positioning System (GPS) variables and the change (Δ; from baseline) in Creatine Kinase (CK) concentrations and peak power output (PPO; during the countermovement jump) at 24 h and 48 h post-match. Fifteen English Premier League reserve team players were examined over 1–4 matches. Measurements of CK and PPO were taken before (24 h prior to match-play) and after (+24 h and +48 h) each game during which movement demands were quantified using 10 Hz GPS data. High intensity distance covered (r = 0.386, p = 0.029; r = −0.349; p = 0.050), high intensity distance covered⋅min⁻¹ (r = 0.365, p = 0.040; r = −0.364, p = 0.040), high speed running distance (r = 0.363, p = 0.041; r = −0.360, p = 0.043) and the number of sprints⋅min⁻¹ (r = 0.410, p = 0.020; r = −0.368, p = 0.038) were significantly related to ΔCK and ΔPPO at +24 h post-match, respectively. No relationships were observed between any match variables and ΔCK and ΔPPO after +48 h of recovery. These findings highlight that high intensity match activities are related to ΔCK and ΔPPO in the 24 h, but not 48 h, following soccer match-play. Such information is likely of interest to those responsible for the design of soccer player’s training schedules in the days following a match.     

Research on effects of pattern,amplitude and frequency of pulse steering torque warnings for lane departure

Driver’s inattention is the main reason for lane departure accidents in highway traffic. In this paper, the pulse steering torque warnings technique is studied, and the effects of pattern, amplitude and frequency of pulse steering torque warnings on the effectiveness and customers’ acceptance are studied through in-door experiments based on a fixed-based driving simulator. Prototypes of lane departure warning system with twelve parameter settings were developed. Three-ways repeated measures ANOVAS and t-test are used to assess the effects of warning systems. The steering behaviors of 20 drivers during lane departure are analyzed. The experimental results show that both primary and secondary interaction of amplitude, frequency and pattern are not significant. The superimposed square pulse steering torque is more effective than triangular pulse one. There is little difference of drivers’ preference in pulse patterns. Although large amplitude is less accepted by drivers, it improves the correction maneuver greatly. 10 Hz is a preferred frequency, which achieves a compromise between effectiveness and drivers’ acceptance. Thus, the combination of small amplitude, square and mid-frequency is the best compromise for practical application.     

Distributed attentional deficits in chronic methamphetamine abusers: Evidence from the Attentional Network Task (ANT)

ObjectiveThe goal of the present study was to examine distributed attentional functions in long-term but currently abstinent methamphetamine (MA) abusers using a task that measures attentional alertness, orienting, and conflict resolution.MethodsThirty currently abstinent MA abusers (1 month–5 years) and 22 healthy non-substance using adults were administered a multimodal version of the Attentional Network Task (ANT-I). In this task subjects identified the direction of a centrally presented arrow using a key press. Analyses examined the interaction between alerting tones, location cueing and congruency between the target arrows and flanking distractor stimuli.ResultsAll participants were faster when an auditory tone preceded the trial onset (p < 0.001), on trials in which a valid cue preceded the location of the target arrow (p < 0.001), and on congruent trials (i.e., when all display arrows faced in the same direction) (p < 0.001). Of primary interest was the finding that MA abusers were more influenced by the conflict between the peripheral arrows and the central target arrow (p = 0.009). There were also correlations between length of drug sobriety and executive function as well as between drug-induced psychiatric symptoms and alertness.ConclusionsThese results suggest that chronic MA abusers display cognitive deficits that may reflect a specific vulnerability to distraction on a task of executive function. These findings are consistent with other studies that have reported deficits in anterior attentional systems and top-down cognitive control.     

Does “chaining” always work towards compliance gaining? The case of the “but you are free” technique and social proof applied to charitable donation

IntroductionThe chaining procedure consists in linking together two or more compliance gaining strategies in order to obtain greater behavioral compliance.ObjectiveIn two studies we tested chaining that included two compliance gaining procedures: the “but you are free” technique (BYAF) and social proof (SP).MethodA total of 2204 passersby were approached in different countries (France, Tunisia, China and Moldavia). They were asked to donate money for cancer research with, respectively, a control formulation, a BYAF formulation, a SP formulation or a BYAF + SP formulation.ResultsObservations indicate that chaining did not work because the BYAF + SP condition produced the same behavioral compliance as BYAF or SP separately (studies 1 and 2). Furthermore, we analyzed the participants’ justifications after complying with or rejecting the request and the reasons were substantially the same under each condition (study 2).ConclusionFailure to observe the chaining process is interpreted through theoretical explanations whereby BYAF and SP are antagonistic.     

Acute effect of stretching modalities on global coordination and kicking accuracy in 12–13 year-old soccer players

The aim of the study was to compare the effect of stretching procedures on global coordination and accuracy in instep soccer kicks achieved in different stress conditions. Twenty male young soccer players completed the global coordination test (GC), the instep kicking accuracy test in free (FKA) and in time-pressure (TPKA) conditions, either after static (SS), dynamic (DS), ballistic (BS) or no-stretching (CTR) protocols, on nonconsecutive days and in a randomized order. After performing a 5 min standardized intensity jogging (70% of MAV), followed by stretching exercises for 10 min, each participant completed, successively, the GC, FKA and TPKA tests. Accuracy data, heart-rate, rating of perceived exertion and task difficulty perception were recorded and analyzed using a two-way ANOVA. GC scores were analyzed using one way ANOVA with repeated measures. The results showed higher GC and TPKA performances after DS and BS procedures. However, there was no effect of the stretching procedures on FKA. The GC scores increased by 10.8% and 7.2% after DS and BS, respectively, but were not affected by SS. Compared to FKA, the TPKA accuracy significantly decreased by 20.2% after CTR (p < 0.01) and 30.7% SS (p < 0.001) with no significant difference after DS (10.1%; p > 0.05) and BS (11.0%; p > 0.05). The use of dynamic and ballistic stretching yielded to better GC scores and helped reducing the adverse effect of time-pressure on instep kicking accuracy. Consequently, dynamic and ballistic exercises can be recommended before practicing activities requiring coordination and lower limbs speed and accuracy.     

Rumination and depression in Chinese university students: The mediating role of overgeneral autobiographical memory

ObjectiveIn this study, we examined the mediator effects of overgeneral autobiographical memory (OGM) on the relationship between rumination and depression in 323 Chinese university students.Method323 undergraduates completed the questionnaires measuring OGM (Autobiographical Memory Test), rumination (Ruminative Response Scale) and depression (Center for Epidemiologic Studies Depression Scale).ResultsResults using structural equation modeling showed that OGM partially-mediated the relationship between rumination and depression (χ² = 88.61, p < .01; RMSEA = .051; SRMR = .040; and CFI = .91). Bootstrap methods were used to assess the magnitude of the indirect effects. The results of the bootstrap estimation procedure and subsequent analyses indicated that the indirect effects of OGM on the relationship between rumination and depressive symptoms were significant.ConclusionThe results indicated that rumination and depression were partially mediated by OGM.     

A meta-analysis of the effectiveness of the low-ball compliance-gaining procedure

IntroductionThe low-ball (Cialdini et al., 1978)¹ is a compliance-gaining technique consisting of making an attractive initial offer to get a person to agree to the request and then making the terms less favorable (target request).Objective and methodsThe effectiveness of this technique was evaluated in a meta-analysis using 17 references, 23 studies, 44 subgroups and a combined sample size of 4733.ResultsAnalysis reported a weighted mean correlation coefficient of r = .16 and a weighted mean odds ratio of OR = 2.47. Moderator analysis reported that the low-ball was more efficient with a high cost request in terms of effort for the participant and when the solicitation of the target request is deferred.ConclusionThese findings appeared congruent with commitment theoretical explanation of the low-ball.     

Achievement goal theory and disordered eating: Relationships of disordered eating with goal orientations and motivational climate in female gymnasts and dancers

ObjectivesTo examine the relationships between disordered eating in female gymnasts and dancers and their perspective towards achievement in sport and dance, respectively. With an emphasis on outperforming others (ego involvement), more disordered eating was expected than when personal progress (task involvement) was emphasized.MethodsNinety-four aesthetic performers from gymnastics (n = 59) and dance (n = 35) completed questionnaires measuring ego and task involvement (individual orientation and motivational climate), dieting, self-esteem, perfectionism and weight-related peer and coach pressure.ResultsPartial correlations indicated that a stronger ego orientation was related to more dieting, greater perfectionism, more weight-related peer pressure, and lower self-esteem. Similar relationships were found for performance climate. Mastery climate on the other hand was negatively related to dieting, and coach and peer pressure, suggesting that when performers perceived the motivational climate as mastery, less frequent dieting was reported and less weight-related coach and peer pressure was perceived. No relationships were found between task orientation and disordered eating. Most importantly, regression analysis showed that after controlling for BMI, both ego orientation and mastery climate made a unique significant contribution to explaining dieting variance.ConclusionsGoal achievement theory is an important framework for explaining disordered eating in female aesthetic performers. Both ego orientation and mastery climate play a role in dieting of gymnasts and dancers. Aesthetic performers who are strongly ego-oriented tend to display more disordered eating correlates. Furthermore, it seems that to protect against disordered eating, coaches and teachers should create a mastery climate and target self-improvement and self-referenced comparisons over interpersonal competitiveness.     

Efficacy of haptic blind spot warnings applied through a steering wheel or a seatbelt

This study evaluates the efficacy of haptic feedback for the Blind Spot Warnings (BSWs) that are delivered to a driver through a steering wheel or a seatbelt. To this end, we developed a virtual driving simulator that implemented potential side collision scenarios. Haptic BSWs were issued as a vibrotactile alert during lane changes if a car in the target lane approached from the participant’s blind spot at a faster speed. The two haptic warning types were assessed through a human factors experiment with participants of two age groups: younger (30–40 years) and older (50–60 years). No warning condition was also included as the control condition. As performance measures, the Collision Prevention Rate (CPR) and the Minimum Distance by which a collision was Avoided (MDA) were collected. As preference measures, the participants’ perception of usefulness of the haptic warnings and their overall satisfaction were used. Experimental results showed that the highest CPR, the longest MDA, and the highest preference were achieved when BSWs were delivered through the steering wheel. For the seatbelt BSW, the CPR and MDA did not increase with statistical significance than those of the no-warning condition, but the participants felt that the haptic seatbelt was useful with high satisfaction. Interestingly, the scores of perceived usefulness and satisfaction were higher with the older group, suggesting that older drivers can be more willing to accept these new types of warning. In addition, the experiment suggested several factors that need to be studied to further improve the performance and preference of haptic BSW, such as warning issue timing and vibration intensity.     

Mechanisms underlying the self-talk–performance relationship: The effects of motivational self-talk on self-confidence and anxiety

ObjectivesThe present study examined the effects of motivational self-talk on self-confidence, anxiety, and task performance in young athletes.MethodsParticipants were 72 tennis players. The experiment was conducted in five sessions: baseline assessment, three training sessions, and final assessment. After the baseline assessment participants were divided and assigned randomly into experimental and control groups. The two groups followed the same training program with the experimental group practicing the use of self-talk. In the last session, the final assessment took place. A forehand drive test was used to evaluate task performance, and the Competitive Anxiety Inventory-2R was used to assess self-confidence and anxiety.ResultsA two-way mixed model MANOVA revealed that task performance improved for the experimental group (p < .01) and remained stable for the control group; self-confidence increased (p < .01) and cognitive anxiety decreased (p < .05) for the experimental group, whereas no changes were observed for the control group. Correlation analysis revealed that changes in task performance were moderately related to changes in self-confidence (p < .05).ConclusionsThe results of the study showed that self-talk can enhance self-confidence and reduce cognitive anxiety. Furthermore, it is suggested that increases in self-confidence can be regarded as a viable function explaining the facilitating effects of self-talk on performance.     

Aging effect on detectability,criticality and urgency under various auditory conditions

The objective of the study was to investigate the relationship between different components of an auditory warning signal and determine elderly driver’s detection, criticality and urgency perceptions under varied auditory warning conditions. A laboratory study was conducted involving 28 younger and 28 older adults. A pure-tone audiogram was administered for quantification of the participant’s hearing level (in dBHL) prior to the test protocols. Audiogram was conducted in a sound isolated booth. The main experiment investigated the effects of frequency, temporal characteristics, aging, and noise on detectability, caution and perceived urgent levels. Method of adjustment was used by the subjects to adjust the sound pressure level (dBA) till they detected, or felt caution or urgent. Overall, the results indicated that elderly had higher sound pressure threshold than younger individuals in all the sessions (i.e., detectability, caution and urgency). Elderly were found to have higher hearing thresholds especially at 4000 Hz. Higher frequencies were also seen to require less sound pressure thresholds to convey feeling of caution and urgency. Sound pressure threshold to convey the feeling of urgency was the lowest for 2000 Hz and 4000 Hz with 1000 Hz requiring the highest threshold intensity. In conclusion, current study findings suggest frequency, temporal and spectral components to influence a person’s criterion. We would recommend the use of complex tones (multi-components) having high frequency around 2000 Hz for detection, warning and urgent conditions.