Can we use anti-predator behavior theory to predict wildlife responses to high-speed vehicles?

Animals seem to rely on antipredator behavior to avoid vehicle collisions. There is an extensive body of antipredator behavior theory that have been used to predict the distance/time animals should escape from predators. These models have also been used to guide empirical research on escape behavior from vehicles. However, little is known as to whether antipredator behavior models are appropriate to apply to an approaching high-speed vehicle. We addressed this gap by (a) providing an overview of the main hypothesis and predictions of different antipredator behavior models via a literature review, (b) exploring whether these models can generate quantitative predictions on escape distance when parameterized with empirical data from the literature, and (c) evaluating their sensitivity to vehicle approach speed via a simulation approach where we assessed model performance based on changes in effect size with variations in the slope of the flight initiation distance (FID) vs. approach speed relationship. We used literature on birds for goals (b) and (c). We considered the following eight models: the economic escape model, Blumstein's economic escape model, the optimal escape model, the perceptual limit hypothesis, the visual cue model, the flush early and avoid the rush (FEAR) hypothesis, the looming stimulus hypothesis, and the Bayesian model of escape behavior. We were able to generate quantitative predictions about escape distances with the last five models. However, we were only able to assess sensitivity to vehicle approach speed for the last three models. The FEAR hypothesis is most sensitive to high-speed vehicles when the species follows the spatial (FID remains constant as speed increases) and the temporal margin of safety (FID increases with an increase in speed) rules of escape. The looming stimulus effect hypothesis reached small to intermediate levels of sensitivity to high-speed vehicles when a species follows the delayed margin of safety (FID decreases with an increase in speed). The Bayesian optimal escape model reached intermediate levels of sensitivity to approach speed across all escape rules (spatial, temporal, delayed margins of safety) but only for larger (> 1 kg) species, but was not sensitive to speed for smaller species. Overall, no single antipredator behavior model could characterize all different types of escape responses relative to vehicle approach speed but some models showed some levels of sensitivity for certain rules of escape. We derive some applied applications of our finding by suggesting the estimation of critical vehicle approach speeds for managing populations that are especially susceptible to road mortality. Overall, we recommend that new escape behavior models specifically tailored to high-speeds vehicles should be developed to better predict quantitatively the responses of animals to an increase in the frequency of cars, airplanes, drones, etc. they will be facing in the next decade.

Effectiveness of Pedestrian Safety Service Provision Using Sensing Technology

In this study, we describe the results of an analysis of the effectiveness of providing pedestrian safety services, in terms of reducing pedestrian traffic accidents. We conducted our analysis by investigating the speed of vehicles at two different demonstration points, where the same system and service were provided. For this purpose, we selected a child protection zone and a point on a general road section where a raised crossing is installed. We conducted vehicle speed surveys at the point adjacent to the crosswalk and the points where the driver is expected to be fully provided with information, in order to examine the change in vehicle approach speed, depending on the provision of the service. Overall, the analysis showed that the vehicle’s speed at the point and approaching speed decreased when the pedestrian safety service was provided; however, the effect was more pronounced in the child protection zone, considering the characteristics of the demonstration points. From these results, we conclude that it is necessary to provide services and develop guidelines considering the surrounding environment, such as traffic safety facilities and road safety facilities, according to the characteristics and classification of each point, in order to provide efficient pedestrian safety services.

MATHEMATICAL MODELING OF COLD PRESSING THE SHEET COMPOSITE

Statement of the problem. The article examines the problem of cold pressing, which is the most important technological component in the production of sheet composite, which is widely studied in the repair and construction works in the interior decoration of residential and industrial premises. The solution to this problem is carried out on the basis of a physical and mathematical model under the assumption that the rheological properties of the deformable medium correspond to the principles of ideal plasticity and a flat deformable state. Within the framework of the problem, in two dimensions of quasistatic compression between absolutely rigid parallel-approaching plates of a thin ideally plastic layer, the stress-strain state of a composite medium is studied. It is believed that in the absence of volumetric loads, the condition of incompressibility of the medium and the associated flow law is fulfilled. Based on the hypothesis of the linear distribution of tangential stresses over the thickness of the deformable layer, analytical expressions for the statistical and kinematic characteristics of the deformation are obtained, and the condition at the edges of the rough plates makes it possible to determine the coefficient of slip thorns, which makes it possible to control the pressing process.Results and conclusions. It was established that the components of the strain rate are directly proportional to the plate approach speed, and the normal stresses acting in the pressing direction are independent of the loading speed, decreasing in magnitude from the center to the periphery.Keywords: yield strength, pressing, plasticity condition, mathematical model.

Tracking Quantitative Characteristics of Cutting Maneuvers with Wearable Movement Sensors during Competitive Women’s Ultimate Frisbee Games

(1) Ultimate frisbee involves frequent cutting motions, which have a high risk of anterior cruciate ligament (ACL) injury, especially for female players. This study investigated the in-game cutting maneuvers performed by female ultimate frisbee athletes to understand the movements that could put them at risk of ACL injury. (2) Lower-body kinematics and movement around the field were reconstructed from wearable lower-body inertial sensors worn by 12 female players during 16 league-sanctioned ultimate frisbee games. (3) 422 cuts were identified from speed and direction change criteria. The mean cut had approach speed of 3.4 m/s, approach acceleration of 3.1 m/s2, cut angle of 94 degrees, and ground-contact knee flexion of 34 degrees. Shallow cuts from 30 to 90 degrees were most common. Speed and acceleration did not change based on cut angle. Players on more competitive teams had higher speed and acceleration and reduced knee flexion during cutting. (4) This study demonstrates that a lower-body set of wearable inertial sensors can successfully track an athlete’s motion during real games, producing detailed biomechanical metrics of behavior and performance. These in-game measurements can be used to specify controlled cutting movements in future laboratory studies. These studies should prioritize higher-level players since they may exhibit higher-risk cutting behavior.

Vision does not impact walking performance in Argentine ants

ABSTRACTMany walking insects use vision for long-distance navigation, but the influence of vision on rapid walking performance that requires close-range obstacle detection and directing the limbs towards stable footholds remains largely untested. We compared Argentine ant (Linepithema humile) workers in light versus darkness while traversing flat and uneven terrain. In darkness, ants reduced flat-ground walking speeds by only 5%. Similarly, the approach speed and time to cross a step obstacle were not significantly affected by lack of lighting. To determine whether tactile sensing might compensate for vision loss, we tracked antennal motion and observed shifts in spatiotemporal activity as a result of terrain structure but not illumination. Together, these findings suggest that vision does not impact walking performance in Argentine ant workers. Our results help contextualize eye variation across ants, including subterranean, nocturnal and eyeless species that walk in complete darkness. More broadly, our findings highlight the importance of integrating vision, proprioception and tactile sensing for robust locomotion in unstructured environments.

Interpretation of the Magnetic Field Signals Emitted by Encoded Asphalt Pavement Materials

Asphalt materials modified with different types and dosages of magnetically responsive materials can emit patterns of magnetic signals easily detectable by magnetic field sensors. These patterns could be used to encode roads and improve infrastructure-to-vehicle (I2V)/road-to-vehicle (R2V) communications. In this sense, this paper presents a laboratory study addressed to analyze the magnetic field signals emitted by encoded asphalt specimens manufactured with various dosages of steel fibers. The analysis consisted in the evaluation of the influence of three parameters: (1) the height of placement of the magnetic field sensors, (2) the approach speed of the encoded specimen/vehicle and (3) the distance from signal detection. Results show that, for each one of the parameters evaluated, there is a limit value below which it is possible to work with the magnetic signal emitted by the encoded samples. A proof of concept was used to validate the results obtained.

Vision does not impact walking performance in Argentine ants

Many walking insects use vision for long-distance navigation, but the influence of vision in detecting close-range obstacles and directing the limbs to maintain stability remains largely untested. We compared Argentine ant workers in light versus darkness while traversing flat and uneven terrain. In darkness, ants reduced flat-ground walking speeds by only 5%. Similarly, neither the approach speed nor the time to cross a step obstacle was affected by lighting. To determine if tactile sensing might compensate for vision loss, we tracked antennal motion and observed shifts in spatiotemporal activity due to terrain structure but not illumination. Together, these findings suggest that vision does not impact walking performance in Argentine ant workers. Our results help contextualize eye variation across ants, including subterranean, nocturnal, and eyeless species that walk in complete darkness. More broadly, our findings highlight the importance of integrating vision, proprioception, and tactile sensing for robust locomotion in unstructured environments.