Reaching the hearts and minds of illiterate women in the Amhara highland of Ethiopia: Development and pre-testing of oral HIV/AIDS prevention messages

In the style of radio programmes, we developed three episodes of audio HIV prevention education for illiterate women in Ethiopia. We used social-oriented presentation formats, such as discussion between women on HIV prevention, and expert-oriented presentation formats, such as an interview with a male doctor. The aim of this study was to assess the relation between evaluation of presentation formats and overall liking of episodes, which is important for persuasive effects. Thirty women from rural Amhara listened to the episodes and, after listening, female data collectors interviewed the women on evaluation of presentation formats, overall liking of episodes, identification with the characters and convincingness. Evaluation of social-oriented presentation formats was strongly related to overall liking of episodes, but evaluation of expert-oriented presentation formats was not. This relation was mediated through convincingness and not through identification. We conclude that social-oriented presentation formats make messages more convincing and, consequently, improve overall liking and persuasive impact

Behavioural validity of driving simulators for prototype HMI evaluation

In-vehicle interfaces are now part of the vast majority of production vehicles. Such interfaces need to be thoroughly evaluated to ensure they do not pose any risks to the drivers using them. Driving simulators have extensively been used in such a context, yet their reliability in terms of how realistic a driving behaviour they elicit is still in question. An investigation on driving simulator behavioural validity in the context of prototype human-machine interface evaluation is presented in this study. Using data collected in a dual setting driving study (driving simulator and real world), as well as results from existing related literature, a comparison between driving behaviour in different types of driving simulators and in reality was carried out, for a variety of behavioural metrics. The results are presented in the form of a `validity matrix' that aggregates the level of behavioural validity different simulator settings can achieve for different behavioural metrics

Using Driver Control Models to Understand and Evaluate Behavioral Validity of Driving Simulators

For a driving simulator to be a valid tool for research, vehicle development, or driver training, it is crucial that it elicits similar driver behavior as the corresponding real vehicle. To assess such behavioral validity, the use of quantitative driver models has been suggested but not previously reported. Here, a task-general conceptual driver model is proposed, along with a taxonomy defining levels of behavioral validity. Based on these theoretical concepts, it is argued that driver models without explicit representations of sensory or neuromuscular dynamics should be sufficient for a model-based assessment of driving simulators in most contexts. As a task-specific example, two parsimonious driver steering models of this nature are developed and tested on a dataset of real and simulated driving in near-limit, low-friction circumstances, indicating a clear preference of one model over the other. By means of closed-loop simulations, it is demonstrated that the parameters of this preferred model can generally be accurately estimated from unperturbed driver steering data, using a simple, open-loop fitting method, as long as the vehicle positioning data are reliable. Some recurring patterns between the two studied tasks are noted in how the model’s parameters, fitted to human steering, are affected by the presence or absence of steering torques and motion cues in the simulator

Understanding Cue Utility in Controlled Evasive Driving Manoeuvres: Optimizing Vestibular Cues for Simulator & Human Abilities

Most daily driving tasks are of low bandwidth and therefore the relatively slow visual system receives enough cue information to perform the task in a manner that is statistically indistinguishable from reality. On the other hand, evasive maneuvers are of such a high bandwidth that waiting for the visual cues to change is too slow and skilled drivers use steering torques and vestibular motion cues to know how the car is responding in order to make rapid corrective actions. In this study we show for evasive maneuvers on snow and ice, for which we have real world data from skilled test drivers, that the choice of motion cuing algorithm (MCA) settings has a tremendous impact on the saliency of motion cues and their similarity with reality. We demonstrate this by introducing a novel optimization scheme to optimize the classic MCA in the context of an MCA-Simulator-Driver triplet of constraints. We incorporate the following four elements to tune the MCA for a particular maneuver: 1) acceleration profiles of the maneuver observed in reality, 2) vestibular motion perception model, 3) motion envelope constraints of the simulator, and 4) a set of heuristics extracted from the literature about human motion perception (i.e. coherence zones). Including these elements in the tuning process, notwithstanding the easiness of the tuning process, respects motion platform constraints and considers human perception. Moreover the inevitable phase and gain errors arising as a major consequence of MCA are always kept within the human coherence zones, and subsequently are not perceptible as false cues. It is expected that this approach to MCA tuning will increase the transfer of training from simulator to reality for evasive driving maneuvers where students need training most and are most dangerous to perform in reality

Risk-based autonomous vehicle motion control with considering human driver’s behaviour

The selected motions of autonomous vehicles (AVs) are subject to the constraints from the surrounding traffic environment, infrastructure and the vehicle’s dynamic capabilities. Normally, the motion control of the vehicle is composed of trajectory planning and trajectory following according to the surrounding risk factors, the vehicles’ capabilities as well as tyre/road interaction situations. However, pure trajectory following with a unique path may make the motion control of the vehicle be too careful and cautious with a large amount of steering effort. To follow a planned trajectory, the AVs with the traditional path-following control algorithms will correct their states even if the vehicles have only a slight deviation from the desired path or the vehicle detects static infrastructure like roadside trees. In this case, the safety of the AVs can be guaranteed to some degree, but the comfort and sense of hazards for the drivers are ignored, and sometimes the AVs have unusual motion behaviours which may not be acceptable to other road users. To solve this problem, this study aims to develop a safety corridor-based vehicle motion control approach by investigating human-driven vehicle behaviour and the vehicle’s dynamic capabilities. The safety corridor is derived by the manoeuvring action feedback of actual drivers as collected in a driving simulator when presented with surrounding risk elements and enables the AVs to have safe trajectories within it. A corridor-based Nonlinear Model Predictive Control (NMPC) has been developed which controls the vehicle state to achieve a smooth and comfortable trajectory while applying trajectory constraints using the safety corridor. The safety corridor and motion controller are assessed using four typical scenarios to show that the vehicle has a human-like or human-oriented behaviour which is expected to be more acceptable for both drivers and other road users

View the label before you view the movie: A field experiment into the impact of Portion size and Guideline Daily Amounts labelling on soft drinks in cinemas

<p>Abstract</p> <p>Background</p> <p>Large soft drink sizes increase consumption, and thereby contribute to obesity. Portion size labelling may help consumers to select more appropriate food portions. This study aimed to assess the effectiveness of portion size and caloric Guidelines for Daily Amounts (GDA) labelling on consumers' portion size choices and consumption of regular soft drinks.</p> <p>Methods</p> <p>A field experiment that took place on two subsequent evenings in a Dutch cinema. Participants (n = 101) were asked to select one of five different portion sizes of a soft drink. Consumers were provided with either portion size and caloric GDA labelling (experimental condition) or with millilitre information (control condition).</p> <p>Results</p> <p>Labelling neither stimulated participants to choose small portion sizes (<it>OR </it>= .75, <it>p </it>= .61, CI: .25 - 2.25), nor did labelling dissuade participants to choose large portion sizes (<it>OR </it>= .51, <it>p </it>= .36, CI: .12 - 2.15).</p> <p>Conclusions</p> <p>Portion size and caloric GDA labelling were found to have no effect on soft drink intake. Further research among a larger group of participants combined with pricing strategies is required. The results of this study are relevant for the current public health debate on food labelling.</p

Measuring Drivers’ Physiological Response to Different Vehicle Controllers in Highly Automated Driving (HAD): Opportunities for Establishing Real-Time Values of Driver Discomfort

This study investigated how driver discomfort was influenced by different types of automated vehicle (AV) controllers, compared to manual driving, and whether this response changed in different road environments, using heart-rate variability (HRV) and electrodermal activity (EDA). A total of 24 drivers were subjected to manual driving and four AV controllers: two modelled to depict “human-like” driving behaviour, one conventional lane-keeping assist controller, and a replay of their own manual drive. Each drive lasted for ~15 min and consisted of rural and urban environments, which differed in terms of average speed, road geometry and road-based furniture. Drivers showed higher skin conductance response (SCR) and lower HRV during manual driving, compared to the automated drives. There were no significant differences in discomfort between the AV controllers. SCRs and subjective discomfort ratings showed significantly higher discomfort in the faster rural environments, when compared to the urban environments. Our results suggest that SCR values are more sensitive than HRV-based measures to continuously evolving situations that induce discomfort. Further research may be warranted in investigating the value of this metric in assessing real-time driver discomfort levels, which may help improve acceptance of AV controllers

Understanding historical coastal spit evolution : a case study from Spurn, East Yorkshire, UK

Globally sandy coastlines are threatened by erosion driven by climatic changes and increased storminess. Understanding how they have responded to past storms is key to help manage future coastal changes. Coastal spits around the world are particularly dynamic and therefore potentially vulnerable coastal features. Therefore, how they have evolved over the last few centuries is of great importance. To illustrate this, this study focuses on the historical evolution of a spit at Spurn on the east coast of the UK, which currently provides critical protection to settlements within the Humber estuary. Through the combination of digitized historical mapping and luminescence dating, this study shows that Spurn has been a consistent coastal feature over at least the past 440 years. No significant westward migration was observed for the last 200 years. Results show a long‐term extension of the spit and a decrease in its overall area, particularly in the last 50 years. Breaches of the neck cause temporary sediment pathway changes enabling westward extension of the head. Use of digitized historical maps in GIS combined with OSL dating has allowed a more complete understanding of long‐term spit evolution and sediment transport modes at Spurn. In doing so it helps inform future possible changes linked to pressures, such as increases in storm events and sea‐level rise

Achieving Driving Comfort of AVs by Combined Longitudinal and Lateral Motion Control

As automated vehicles (AVs) are moving closer to practical reality, one of the problems that needs to be resolved is how to achieve an acceptable and natural risk management behaviour for the on-board users. Cautious automated driving behaviour is normally demonstrated during the AV testing, by which the safety issue between the AV and other road users or other static risk elements can be guaranteed. However, excessive cautiousness of the AVs may lead to traffic congestion and strange behaviour that will not be accepted by drivers and other road users. Human-like automated driving, as an emerging technique, has been concentrated on mimicking a human driver’s behaviour in order that the behaviour of the AVs can provide an acceptable behaviour for both the drivers (and passengers) and the other road users. The human drivers’ behaviour was obtained through simulator based driving and this study developed a nonlinear model predictive control to optimise risk management behaviour of AVs by taking into account human-driven vehicles’ behaviour, in both longitudinal and lateral directions

D3-instantons, Mock Theta Series and Twistors

The D-instanton corrected hypermultiplet moduli space of type II string theory compactified on a Calabi-Yau threefold is known in the type IIA picture to be determined in terms of the generalized Donaldson-Thomas invariants, through a twistorial construction. At the same time, in the mirror type IIB picture, and in the limit where only D3-D1-D(-1)-instanton corrections are retained, it should carry an isometric action of the S-duality group SL(2,Z). We prove that this is the case in the one-instanton approximation, by constructing a holomorphic action of SL(2,Z) on the linearized twistor space. Using the modular invariance of the D4-D2-D0 black hole partition function, we show that the standard Darboux coordinates in twistor space have modular anomalies controlled by period integrals of a Siegel-Narain theta series, which can be canceled by a contact transformation generated by a holomorphic mock theta series.Comment: 42 pages; discussion of isometries is amended; misprints correcte