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There is a critical need to understand how aging visual systems contribute to age-related increases in vehicle accidents. We investigated the potential contribution of age-related detriments in steering based on optic flow, a source of information known to play a role in navigation control. Seventeen younger adults (mean age: 21.1 years) and thirteen older adults (mean age: 57.3 years) performed a virtual reality steering task. The virtual environment depicted movement at 19 m/s along a winding road. Participants were tasked with maintaining a central lane position while experiencing eight repetitions of each combination of optic flow density (low, medium, high), turn radius (35, 55, 75 m), and turn direction (left, right), presented in random order. All participants cut corners, but did so less on turns with rotational flow from distant landmarks and without proximal optic flow. We found no evidence of an interaction between age and optic flow density, although older adults cut corners more on all turns. An exploratory gaze analysis revealed no age-related differences in gaze behavior. The lack of age-related differences in steering or gaze behavior as a function of optic flow implies that processing of naturalistic optic flow stimuli when steering may be preserved with age. [ABSTRACT FROM AUTHOR]

Sensor technologies were integrated into a commercial sensor-guided hoeing system to counteract the force of gravity and reduce crop damage caused by the offset of hoeing in maize fields on sloping terrains. For this study, a hoe was equipped with a contact disc, sensors, an electric cylinder, and a decision support system. The offset of the hoe could be compensated in real time based on the automatic adjustment angle of the support wheel. In maize, three field experiments were conducted over two years to evaluate the system on three different slope gradients (between 4 and 12°). Plant populations were measured in each plot one day before and during hoeing to evaluate crop damage. However, for support wheel angle, Slope Compensation Intensity (SCI) 2 and 3, there were no significant crop plant losses in any trials. As a result, there was no hoe drifting during the sensor-based guidance along the rows. It has been verified that the development presented is functional and can counteract the force of gravity on slopes. This development aims to optimise the use of precision mechanical weed control and support farmers during hoeing on hilly terrain. • Tractor and machine are pushed down the slope by downhill force. • The hoe is not parallel to the tractor and plant losses will occur. • The offset of a hoe can be compensated by the developed slope-compensation system. • Crop losses can be compensated on hilly fields. [ABSTRACT FROM AUTHOR]

Stewardship theory offers considerable promise for strengthening trust between governments and organizations implementing policy. Recent studies show stewardship is partially applicable to the steering of public organizations yet it is not clear under what conditions. This study asserts that the steering of governmental organizations needs to be aligned with preferences and conditions of organizations, combining principal-agent and stewardship theory. The article adopts a unique nested comparative mixed methods study focusing on perceived and preferred steering of Danish agencies and educational institutions. The study finds a higher alignment of steering for agencies, mostly because participants experience real partnerships and closer proximity. [ABSTRACT FROM AUTHOR]

Locomotion involves rhythmic limb movement patterns that originate in circuits outside the brain. Purposeful locomotion requires descending commands from the brain, but we do not understand how these commands are structured. Here, we investigate this issue, focusing on the control of steering in walking Drosophila. First, we describe different limb "gestures" associated with different steering maneuvers. Next, we identify a set of descending neurons whose activity predicts steering. Focusing on two descending cell types downstream of distinct brain networks, we show that they evoke specific limb gestures: one lengthens strides on the outside of a turn, while the other attenuates strides on the inside of a turn. Our results suggest that a single descending neuron can have opposite effects during different locomotor rhythm phases, and we identify networks positioned to implement this phase-specific gating. Together, our results show how purposeful locomotion emerges from specific, coordinated modulations of low-level patterns. [Display omitted] • Different steering maneuvers use different combinations of leg gestures • Different descending neurons (DNs) drive different leg gestures • DNa02 shortens strides on the inside of a turn; DNg13 lengthens strides on the outside • DNa02 and DNg13 receive distinct input and can be differentially recruited The brain's role in generating purposeful locomotion depends on a set of descending neurons to the ventral nerve cord that produce coordinated patterns of limb movements, or "gestures," in walking Drosophila. These gestures represent elemental features of locomotion that, when evoked by differential recruitment of descending neurons, produce distinct steering maneuvers. [ABSTRACT FROM AUTHOR]

This paper presents an in-depth analysis of steering and guidance problems of independently rotating wheels (IRWs) in railway vehicles and provides an engineering insight into the possibilities for passive and/or semi-active control possibilities that do not require expensive full-active systems. The theoretical development is then supported in the study by carrying out a comprehensive performance evaluation in comparison with a full active control. The study demonstrates that the independently rotating wheelset may be effectively controlled via semi-active approaches to provide the wheelsets with the necessary steering on curves and self-centring ability on a straight track with irregularities with performance comparable with full active systems. [ABSTRACT FROM AUTHOR]

Abstract There is a critical need to understand how aging visual systems contribute to age-related increases in vehicle accidents. We investigated the potential contribution of age-related detriments in steering based on optic flow, a source of information known to play a role in navigation control. Seventeen younger adults (mean age: 21.1 years) and thirteen older adults (mean age: 57.3 years) performed a virtual reality steering task. The virtual environment depicted movement at 19 m/s along a winding road. Participants were tasked with maintaining a central lane position while experiencing eight repetitions of each combination of optic flow density (low, medium, high), turn radius (35, 55, 75 m), and turn direction (left, right), presented in random order. All participants cut corners, but did so less on turns with rotational flow from distant landmarks and without proximal optic flow. We found no evidence of an interaction between age and optic flow density, although older adults cut corners more on all turns. An exploratory gaze analysis revealed no age-related differences in gaze behavior. The lack of age-related differences in steering or gaze behavior as a function of optic flow implies that processing of naturalistic optic flow stimuli when steering may be preserved with age.

In addressing the steering stability issues of four-wheel-drive electric vehicles on surfaces such as wet, slippery, frozen, and soft terrains, a novel control method based on particle swarm optimization for neural networks is proposed in this study. The approach integrates the advantages of Proportional-Integral- Derivative control, particle swarm optimization, and neural networks. By constructing a neural network model with input, hidden, and output layers, the study introduces particle swarm optimization algorithm for weight and structure optimization. Fuzzy logic and slip control theory are integrated into the steering stability control. The results demonstrated that, under wet and slippery road conditions, the model exhibited a system response time of 15 ms with a steering prediction accuracy of up to 92%. On frozen road surfaces, the model showed a system response time of 18 ms, with a steering prediction accuracy reaching 90%. Compared to other models, it significantly demonstrated superior steering stability control. This suggests that the designed model performs well in handling complex driving environments, indicating high application potential in the field of electric vehicle steering stability control. [ABSTRACT FROM AUTHOR]

This paper offers an ethical analysis of online steering, the practice of personalizing search results in e-commerce based on data about users. We first outline the parallels and differences between online steering and price discrimination, arguing that online steering is more likely to benefit consumers and enhance social welfare than price discrimination. Next, we argue that while online steering does not violate any plausible specification of the equal-treatment norm, it involves an element of manipulation that is absent in price discrimination and that by itself raises ethical concerns regardless of the welfare effects of online steering. We conclude that in order to address these ethical concerns, online steering needs to satisfy a transparency condition. [ABSTRACT FROM AUTHOR]

Accident analyses repeatedly reported the considerable contribution of run-offroad incidents to fatalities in road traffic, and despite considerable advances in assistive technologies to mitigate devastating consequences, little insight into the drivers' brain response during such accident scenarios has been gained. While various literature documents neural correlates to steering motion, the driver's mental state, and the impact of distraction and fatigue on driving performance, the cortical substrate of continuous deviations of a car from the road - i.e., how the brain represents a varying discrepancy between the intended and observed car position and subsequently assigns customized levels of corrective measures - remains unclear. Furthermore, the superposition of multiple subprocesses, such as visual and erroneous feedback processing, performance monitoring, or motor control, complicates a clear interpretation of engaged brain regions within car driving tasks. In the present study, we thus attempted to disentangle these subprocesses, employing passive and active steering conditions within both error-free and error-prone vehicle operation conditions. We recorded EEG signals of 26 participants in 13 sessions, simultaneously measuring pairs of Executors (actively steering) and Observers (strictly observing) during a car driving task. We observed common brain patterns in the Executors regardless of error-free or error-prone vehicle operation, albeit with a shift in spectral activity from motor beta to occipital alpha oscillations within erroneous conditions. Further, significant frontocentral differences between Observers and Executors, tracing back to the caudal anterior cingulate cortex, arose during active steering conditions, indicating increased levels of motor-behavioral cognitive control. Finally, we present regression results of both the steering signal and the car position, indicating that a regression of continuous deviations from the road utilizing the EEG might be feasible. [ABSTRACT FROM AUTHOR]

Tracking performance and stability of path tracking is crucial for unmanned vehicles' navigational tasks. Researches on vehicle path tracking controllers primarily rely on dynamic models. In contrast, there are less designs and researches that focus on path tracking controller based on kinematic model. This scarcity may stem from the perceived inadequacy in the accuracy of vehicle kinematic models. This research introduces a novel method for modifying the traditional vehicle kinematic model by incorporating a front wheel steering angle modification function to enhance tracking performance of path tracking controllers based on kinematic models. In terms of control strategy selection, the study opted for nonlinear model predictive control with terminal cost. A controller which is founded on the modified model was used on a simulated vehicle on CarSim-Simulink platform to assess the tracking performance. The simulation was designed with a double-shift line reference trajectory and the initial speeds of the simulated vehicle are 5 m/s and 10 m/s, respectively. The results of the simulations indicate that employing a controller based on the modified model could reduce the peak tracking error by 76.45 % and 43.06 %, and the root mean square of the tracking error was reduced by 73.29 % and 36.06 %, respectively.

Los entornos virtuales son herramientas altamente utilizadas para el desarrollo de sistemas de entrenamiento médico, industrial, educativo, entretenimiento, entre otras. El avance tecnológico permite que los ambientes virtuales sean realistas y que la interacción con el usuario permita una adecuación o mejora a los ambientes para realizar una tarea. La inteligencia artificial propone la creación de entidades autónomas capaces de acompañar al usuario interactuando con él para el cumplimiento de objetivos (tareas). De ahí, el desarrollo de sistemas autónomos que puedan interactuar y adaptarse de manera efectiva a los usuarios y al entorno en el que se encuentra, exhibiendo un comportamiento realista similar al del mundo real. En este artículo se propone una metodología para la implementación de comportamientos autónomos en entidades virtuales (entornos virtuales) basada en una recombinación de inteligencia artificial y steering (flujos), con el propósito de exhibir comportamientos durante la evacuación de zonas en riesgo, permitiendo anticiparse a posibles contingencias y que los seres humanos puedan actuar de forma adecuada cuando se encuentren en este tipo de situaciones. Los resultados obtenidos utilizando la metodología propuesta permiten observar comportamientos deseados en la evacuación de espacios confinados, así como diferentes tipos de formaciones que son difíciles de tratar utilizando la técnica de steering.

In chaos control, one usually seeks to stabilize the unstable periodic orbits (UPOs) that densely inhabit the attractors of many chaotic dynamical systems. These orbits collectively play a significant role in determining the dynamics and properties of chaotic systems and are said to form the skeleton of the associated attractors. While UPOs are insightful tools for analysis, they are naturally unstable and, as such, are difficult to find and computationally expensive to stabilize. An alternative to using UPOs is to approximate them using cupolets. Cupolets, a name derived from chaotic, unstable, periodic, orbit-lets, are a relatively new class of waveforms that represent highly accurate approximations to the UPOs of chaotic systems, but which are generated via a particular control scheme that applies tiny perturbations along Poincaré sections. Originally discovered in an application of secure chaotic communications, cupolets have since gone on to play pivotal roles in a number of theoretical and practical applications. These developments include using cupolets as wavelets for image compression, targeting in dynamical systems, a chaotic analog to quantum entanglement, an abstract reducibility classification, a basis for audio and video compression, and, most recently, their detection in a chaotic neuron model. This review will detail the historical development of cupolets, how they are generated, and their successful integration into theoretical and computational science and will also identify some unanswered questions and future directions for this work.

Bell non-locality and steering are archetypal characteristics of quantum mechanics that mark a significant departure from conventional classical notions. They basically refer to the presence of quantum correlations between separated systems which violate a non-local inequality, the violation otherwise is not possible if we restrict ourselves only to classical correlations. In view of the importance of such unique correlations, one may be interested to generate more states exhibiting non-locality starting from a few, a protocol which is termed as broadcasting. However, in the present submission, we show using universal Buzek–Hillary (BH) quantum cloning machine that, if one restricts to broadcasting through local quantum cloning, then such non-locality cannot be broadcasted. Our study is done in the purview of the Bell-CHSH inequality and the CJWR [E G Cavalcanti et al, Phys. Rev. A80, 032112 (2009)] steering inequality. It is observed that when the number of measurement settings is greater than 6, some of the output states are steerable after the application of local optimal BH cloners. We found that, under some restrictions, if the Werner and Bell diagonal states are subjected to such procedures, then the resultant state is rendered unsteerable. We extended this study to three qubit systems and found that genuine tripartite non-locality cannot be broadcasted using universal BH local quantum cloners, when the Svetlichny's inequality was considered. For two qubit systems, we considered 10 5 simulated general local unitaries over Werner and Bell-diagonal states and found that for none of these states, broadcasting on non-locality and 3-steerability is possible. [ABSTRACT FROM AUTHOR]

In chaos control, one usually seeks to stabilize the unstable periodic orbits (UPOs) that densely inhabit the attractors of many chaotic dynamical systems. These orbits collectively play a significant role in determining the dynamics and properties of chaotic systems and are said to form the skeleton of the associated attractors. While UPOs are insightful tools for analysis, they are naturally unstable and, as such, are difficult to find and computationally expensive to stabilize. An alternative to using UPOs is to approximate them using cupolets. Cupolets, a name derived from chaotic, unstable, periodic, orbit-lets, are a relatively new class of waveforms that represent highly accurate approximations to the UPOs of chaotic systems, but which are generated via a particular control scheme that applies tiny perturbations along Poincaré sections. Originally discovered in an application of secure chaotic communications, cupolets have since gone on to play pivotal roles in a number of theoretical and practical applications. These developments include using cupolets as wavelets for image compression, targeting in dynamical systems, a chaotic analog to quantum entanglement, an abstract reducibility classification, a basis for audio and video compression, and, most recently, their detection in a chaotic neuron model. This review will detail the historical development of cupolets, how they are generated, and their successful integration into theoretical and computational science and will also identify some unanswered questions and future directions for this work. [ABSTRACT FROM AUTHOR]

In January–February 2019, a monsoon low developed over northeastern Australia and brought extreme flooding to much of tropical Queensland. The European Centre for Medium Range Weather Forecasts reanalyses are used to explain the formation and severity of the event. Strong anticyclonic Rossby wave breaking to the southeast of Australia produced weak steering winds over northern Australia, and consequently the low remained nearly stationary for over a week, contributing to the extreme rainfall. Furthermore, the tropical moist margin was deformed by a series of disturbances along the monsoon trough, which drew moist maritime air over land. The event examined has much in common with the composite mean of slow‐moving potential vorticity anomalies in North Queensland, including weak background winds and heavy precipitation. An ensemble subseasonal forecast with the Australian Bureau of Meteorology's Australian Community Climate and Earth System Simulator Seasonal prediction version system 1 shows the same relationship between the background flow, the steering, and the subsequent rainfall. Hence, accurately forecasting the background winds is a prerequisite to forecasting such extreme rainfall. [ABSTRACT FROM AUTHOR]

This study examines the analysis of the teleportation process in a two-qubit state, particularly scrutinizing the interplay of atomic dipole coupling interaction, the detuning parameter, photon count, and the surrounding environment. Our investigation assumes the existence of a teleportation channel comprising two-qubit systems interacting with a photon field enveloped by the dephasing environment. Within this framework, we closely examine the quantum correlations exhibited by the teleported state, encompassing dimensions of entanglement, steering, and non-locality. Our results underscore the pivotal role played by the initial state of the atomic and field subsystems in shaping quantum relations. The dipole coupling has a profound impact, significantly enhancing the three quantifiers. Particularly, the entanglement changes from a de-entangled state to a partially entangled state. On the other hand, the detuning parameter introduces distortion in the quantum correlations, a phenomenon that can be effectively mitigated by controlling the dipole coupling.

An overview is provided of behavioral research into human steering and collision avoidance including the processing of optic flow, optical looming and the role of the human mobile gaze system. A consideration is then made of the issues that may occur for autonomous vehicles (AV) when they move from gridtype road networks into complex inner-city streets and interact with human drivers, pedestrians and cyclists. Comparisons between human processing and AV processing of these interactions are made. This raises issues as to whether AV control systems need to mimic human visual processing more closely and highlights the need for AV systems to develop a "theory of road users" that allows attribution of intent to other drivers, cyclists or pedestrians. Guidelines for the development of a "theory of road users" for AVs are suggested. [ABSTRACT FROM AUTHOR]

Quantum steering refers to the apparent possibility of exploiting nonseparable quantum correlations to remotely influence the quantum state of an observer via local measurements. Different from entanglement and Bell nonlocality, quantum steering exhibits an inherent asymmetric property, which makes it relevant for many asymmetric quantum information processing tasks. Here, we study Gaussian quantum steering between two mechanical modes in an optomechanical ring cavity. Using experimentally feasible parameters, we show that the state of the two considered modes can exhibit two-way steering and even one-way steering. Instead of using unbalanced losses or noises, we propose a simple practical way to control the direction of one-way steering. A comparative study between the steering and entanglement of the studied modes shows that both steering and entanglement undergo a sudden death-like behavior. In particular, steering is found more fragile against thermal noise remaining constantly upper-bounded by entanglement. The proposed scheme may be meaningful for one-sided device-independent quantum key distribution, where the security of such protocol depends fundamentally on the direction of steering. [ABSTRACT FROM AUTHOR]

A key issue for the design of online marketplaces is addressing leakage. Buyers may use the marketplace to discover a seller or to obtain certain conveniences, but the seller may then want to take transactions off the marketplace to avoid transaction fees. Assuming buyers are heterogenous in their switching cost or inconvenience cost of purchasing directly, we provide a model in which there is partial leakage in equilibrium. We use the model to analyze the trade-offs associated with different strategies the marketplace can use to attenuate the effects of leakage: investing in transaction benefits, limiting communication, charging referral fees, using price-parity clauses, introducing seller competition on the marketplace, and hiding sellers that try to induce too much leakage. This paper was accepted by Joshua Gans, business strategy. Supplemental Material: The online appendix is available at https://doi.org/10.1287/mnsc.2023.4757. [ABSTRACT FROM AUTHOR]

• Drivers can initiate steering to recover from a lane departure while looking off-road. • Primary corrective steering amplitudes can be modeled using a single predictor. • Drivers scale the steering amplitude to get back in lane already at first response. • Splay angles had the strongest influence on steering amplitudes in naturalistic data. • Relative yaw angle influenced the steering amplitude most in driving simulator data. Unintentional lane departures on straight roads cause many road fatalities each year. The objective of this study was to explore and model drivers' recovery steering maneuvers in unintentional drift situations, to enable the prospective safety benefit assessment of lane departure warning and avoidance systems through counterfactual simulations. The timing and amplitude of the steering adjustments drivers make to avoid lane departure were studied over three data sets with different origins, consisting of both naturalistic data and experimental data from a driving simulator study. With respect to timing, the main finding was that visually distracted drivers often initiate the corrective steering response prior to looking back towards the road, demonstrating that lane-keeping information in the visual periphery is sufficient to trigger the response. As for steering amplitude, the observed amplitudes were correlated against different lane departure risk metrics from the literature, resulting in a model capable of accounting for human behavior across all three data sets with good performance. Surprisingly, a very simple model (which describes the steering amplitude as increasing quadratically with the vehicle's orientation to the road) predicted the amplitude of the primary corrective steering adjustment better than models based on more complex lane departure risk metrics. This result indicates that drivers scale the amplitude of their steering adjustment to the steering input needed to get the vehicle back in the lane already at first response. However, it was possible to obtain a similar model fit using a more complex threshold model, with different dynamics depending on the vehicle's current orientation to the road. We discuss how these findings can be applied to models of human steering for safety benefit assessment. [ABSTRACT FROM AUTHOR]

This conceptual study aims to produce rough analysis methods and visualizations for production data (formatted in time, location, and work) that can be collected from construction sites that utilize takt production. The scope is on creating methods for evaluating the soundness of the takt plan and its execution. Relevant production literature regarding takt production management and data collection are utilized in the production of the methods and visualizations. However, only imaginary production data are utilized in this study to keep the indicators as simplified and clear as possible. A total of seven indicators with varying levels of novelty are provided in the study. The proposed indicators emphasize punctual adherence to the takt schedule, homogenous production pace, avoiding trade overlapping in locations, steady work in process, and coherent short and long-term production targets. Both as-planned and as-built perspectives are considered. The proposed indicators are argued to be valuable for production management and research and development processes since they provide status information and document the progression of the production for later indicators purposes. This study also acts as a foundation for further empirical studies regarding takt production data utilization. [ABSTRACT FROM AUTHOR]

At a time when science and participatory research are developing, we need to look at the more or less inclusive ways of “producing with”, in order to measure the effects on the perpetuation or reduction of inequalities within them. It is in the interests of all concerned to develop this reflection in a dialogue between science and society, and not just from the point of view of academic researchers. Drawing parallels between the dilemmas and false pretenses of participation in various social worlds, this article first explores the phenomenon of the redoubling of inequalities, a drama that is replayed in comparable ways in participatory democracy and participatory research. The second part, which focuses on the levers that can be used to combat social inequalities and epistemic injustices, provides keys for analysing the issues of plural steering and cross-validation of participatory approaches.

Accident analyses repeatedly reported the considerable contribution of run-off-road incidents to fatalities in road traffic, and despite considerable advances in assistive technologies to mitigate devastating consequences, little insight into the drivers’ brain response during such accident scenarios has been gained. While various literature documents neural correlates to steering motion, the driver’s mental state, and the impact of distraction and fatigue on driving performance, the cortical substrate of continuous deviations of a car from the road – i.e., how the brain represents a varying discrepancy between the intended and observed car position and subsequently assigns customized levels of corrective measures – remains unclear. Furthermore, the superposition of multiple subprocesses, such as visual and erroneous feedback processing, performance monitoring, or motor control, complicates a clear interpretation of engaged brain regions within car driving tasks. In the present study, we thus attempted to disentangle these subprocesses, employing passive and active steering conditions within both error-free and error-prone vehicle operation conditions. We recorded EEG signals of 26 participants in 13 sessions, simultaneously measuring pairs of Executors (actively steering) and Observers (strictly observing) during a car driving task. We observed common brain patterns in the Executors regardless of error-free or error-prone vehicle operation, albeit with a shift in spectral activity from motor beta to occipital alpha oscillations within erroneous conditions. Further, significant frontocentral differences between Observers and Executors, tracing back to the caudal anterior cingulate cortex, arose during active steering conditions, indicating increased levels of motor-behavioral cognitive control. Finally, we present regression results of both the steering signal and the car position, indicating that a regression of continuous deviations from the road utilizing the EEG might be feasible.

The aim of this study is to revisit the important question of how human drivers steer in straight and curved roads. We review the two-point and the tangent point models and suggest a new perspective by introducing the center point model. An eye tracking platform was used to investigate the driver’s gaze direction in real-time driving. Extensive data was collected in an urban environment via integration of the eye tracking system and a scene camera. The objectives of the experiments were to investigate the driver gaze behaviour in two scenarios in real traffic settings. In the first set of trials, the driver followed the tangent method whereas in the second set of tests, the driver focused on the perceived center of the road during driving in straight and curved roads. Moreover, the distance between the driver and the gaze point is found to be lower when turning left compared to turning right. This study underpins the improved performance of the center point model over the tangent point model. Furthermore, our analysis reveals correlation between gaze strategy and vehicular control, offering a deeper comprehension of visuomotor coordination essential for safe and efficient driving.These findings provide valuable insight into human driving behavior and can be utilized to develop more effective driver assistance systems and enhance lateral control mechanisms for driverless cars.

Abstract Background Manual wheelchair propulsion is widely accepted to be biomechanically inefficient, with a high prevalence of shoulder pain and injuries among users. Directional control during wheelchair movement is a major, yet largely overlooked source of energy loss: changing direction or maintaining straightforward motion on tilted surfaces requires unilateral braking. This study evaluates the efficiency of a novel steering-by-leaning mechanism that guides wheelchair turning through upper body leaning. Methods 16 full-time wheelchair users and 15 able-bodied novices each completed 12 circuits of an adapted Illinois Agility Test-course that included tilted, straight, slalom, and 180° turning sections in a prototype wheelchair at a self-selected functional speed. Trials were alternated between conventional and steering-by-leaning modes while propulsion forces were recorded via instrumented wheelchair wheels. Time to completion, travelled distance, positive/negative power, and work done, were all calculated to allow comparison of the control modes using repeated measures analysis of variance. Results Substantial average energy reductions of 51% (able-bodied group) and 35% (wheelchair user group) to complete the task were observed when using the steering-by-leaning system. Simultaneously, able-bodied subjects were approximately 23% faster whereby completion times did not differ for wheelchair users. Participants in both groups wheeled some 10% further with the novel system. Differences were most pronounced during turning and on tilted surfaces where the steering-by-leaning system removed the need for braking for directional control. Conclusions Backrest-actuated steering systems on manual wheelchairs can make a meaningful contribution towards reducing shoulder usage while contributing to independent living. Optimisation of propulsion techniques could further improve functional outcomes.

Magnetic nanoparticles are used in a wide range of medical applications. However, the accurate steering of the particles through the vascular system is still an open research question. Thus, this paper introduces a novel hybrid magnetic array for steering magnetic nanoparticles through a bifurcation. The array consists of permanent plus electromagnets and is based on a Halbach structure. It combines the advantages of the strong magnetic field of low-cost permanent magnets with the adjustability of electromagnets. The array is investigated numerically in a 3D model using COMSOL Multiphysics. In the simulations, the propagation of the particles in a symmetrical bifurcation is analyzed for discrete coil currents in the range of −10A to 10 A. The results reveal that for low negative currents of −1A to −0.5 A, the influence of the magnetic field of the permanent magnets can be almost completely eliminated, and only 0.5% and 0.9 %, respectively, of the particles were trapped by the magnets. Thus, the hybrid array outperforms the reference of a Halbach array fully built of permanent magnets. Overall, the proposed hybrid array is much more flexible, and the magnetic force can be adjusted more precisely compared to an array of permanent magnets.

An overview is provided of behavioral research into human steering and collision avoidance including the processing of optic flow, optical looming and the role of the human mobile gaze system. A consideration is then made of the issues that may occur for autonomous vehicles (AV) when they move from grid-type road networks into complex inner-city streets and interact with human drivers, pedestrians and cyclists. Comparisons between human processing and AV processing of these interactions are made. This raises issues as to whether AV control systems need to mimic human visual processing more closely and highlights the need for AV systems to develop a “theory of road users” that allows attribution of intent to other drivers, cyclists or pedestrians. Guidelines for the development of a “theory of road users” for AVs are suggested.

Introduction: Directional Leads (dLeads) represent a new technical tool in Deep Brain Stimulation (DBS), and a rapidly growing population of patients receive dLeads. Research question: The European Association of Neurosurgical Societies(EANS) functional neurosurgery Task Force on dLeads conducted a survey of DBS specialists in Europe to evaluate their use, applications, advantages, and disadvantages. Material and methods: EANS functional neurosurgery and European Society for Stereotactic and Functional Neurosurgery (ESSFN) members were asked to complete an online survey with 50 multiple-choice and open questions on their use of dLeads in clinical practice. Results: Forty-nine respondents from 16 countries participated in the survey (n = 38 neurosurgeons, n = 8 neurologists, n = 3 DBS nurses). Five had not used dLeads. All users reported that dLeads provided an advantage (n = 23 minor, n = 21 major). Most surgeons (n = 35) stated that trajectory planning does not differ when implanting dLeads or conventional leads. Most respondents selected dLeads for the ability to optimize stimulation parameters (n = 41). However, the majority (n = 24), regarded time-consuming programming as the main disadvantage of this technology. Innovations that were highly valued by most participants included full 3T MRI compatibility, remote programming, and closed loop technology. Discussion and conclusion: Directional leads are widely used by European DBS specialists. Despite challenges with programming time, users report that dLeads have had a positive impact and maintain an optimistic view of future technological advances.

This paper provides a simulation analysis of the braking action that would prevent untripped rollovers of long combination vehicles (LCV) in turns when the entry speed into a turn exceeds the vehicle's threshold. A co-simulation model is used to integrate the details of truck pneumatic brakes (developed in Simulink®) in a TruckSim® model. The models are validated with field-test data. Using the validated models, various braking initiation times (relative to the start of steering) are performed for a 150-ft J-turn. The simulation results reveal that at higher speeds, there is very little time for the driver to initiate braking before it is too late to avoid a rollover, referred to as Critical Brake Initiation Time (CBIT). For instance, at an entry speed of 40 mph (64 km/hr), applying the brakes for a fully-loaded truck beyond 1.0s would not prevent a rollover. The results also indicate that increasing the speed by 25% from 40 mph (64 km/hr) to 50 mph (80 km/hr), reduces CBIT by 90%, from 1.0s to 0.1s. The effect of cargo load on CBIT is less dramatic than speed. At 40 mph (64 km/hr), increasing the cargo load by 47%, from 15,000 lb. (6800 kg) to 22,000lb. (10,000 kg), decreases the CBIT by 17%, from 1.2s to 1.0s. [ABSTRACT FROM AUTHOR]

The article introduces a novel approach for memoryless local planners, employing depth-based sampling and steering constraints to enhance computational efficiency and planning performance for quadrotors navigating cluttered environments. This approach enables autonomous flight planning without the need for high-level global planners, marking a significant advancement in this field.

Background: Manual wheelchair propulsion is widely accepted to be biomechanically inefficient, with a high prevalence of shoulder pain and injuries among users. Directional control during wheelchair movement is a major, yet largely overlooked source of energy loss: changing direction or maintaining straightforward motion on tilted surfaces requires unilateral braking. This study evaluates the efficiency of a novel steering-by-leaning mechanism that guides wheelchair turning through upper body leaning. Methods: 16 full-time wheelchair users and 15 able-bodied novices each completed 12 circuits of an adapted Illinois Agility Test-course that included tilted, straight, slalom, and 180° turning sections in a prototype wheelchair at a self-selected functional speed. Trials were alternated between conventional and steering-by-leaning modes while propulsion forces were recorded via instrumented wheelchair wheels. Time to completion, travelled distance, positive/negative power, and work done, were all calculated to allow comparison of the control modes using repeated measures analysis of variance. Results: Substantial average energy reductions of 51% (able-bodied group) and 35% (wheelchair user group) to complete the task were observed when using the steering-by-leaning system. Simultaneously, able-bodied subjects were approximately 23% faster whereby completion times did not differ for wheelchair users. Participants in both groups wheeled some 10% further with the novel system. Differences were most pronounced during turning and on tilted surfaces where the steering-by-leaning system removed the need for braking for directional control. Conclusions: Backrest-actuated steering systems on manual wheelchairs can make a meaningful contribution towards reducing shoulder usage while contributing to independent living. Optimisation of propulsion techniques could further improve functional outcomes. [ABSTRACT FROM AUTHOR]

In this article, the proposed antenna structure is designed for modern wireless communication systems. The antenna structure is consistent with 11‐unit cells of composite right–left‐hand (CRLH) inclusions mounted on an FR4 substrate. Therefore, the antenna size is miniaturized effectively to 30 × 20 mm2 to cover the frequency bands around 2.45 GHz, for Wi‐Fi, and 4.2–6 GHz, for sub‐6 5G, networks. The design process is conducted on a circuit model and numerical simulations by evaluating the unit cell transmission phase spectra. For this, a comparison between the circuit model and the numerical simulations is invoked for validation. Such an antenna is found to provide a maximum gain of 6.2 dBi at 4.6 GHz. Next, 11 PIN diodes control the current motion between the antenna patch and the CRLH array. Therefore, PIN arrays are connected to the patch and the ground plane to maintain the surface current motion that realizes main lobe beam steering. The proposed antenna performance is simulated numerically using the CSTMWS software package. Then, it is fabricated and tested experimentally for validation. An excellent agreement is achieved between the simulated and measured results. Finally, it is found this antenna provides excellent beam steering −92° to 92° to suit many modern networks. [ABSTRACT FROM AUTHOR]

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