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This paper aims to clarify the behavior and damage conditions of batteries when multi-rotor unmanned aerial vehicles (drones) in horizontal flight collide with a structure to obtain the engineering knowledge that serves to consider the method of the safety performance evaluation of drone batteries in the collision. Drones with maximum takeoff weight of 15.5 kg, 24.5 kg, and 50 kg for aerial photographing, agricultural chemical spraying, and material transporting were used in the experiment analysis. The drones were ejected from an ejection system and collided with a barrier. The behavior of the drones and the batteries were captured on high-speed cameras. In addition, collision loads on the barrier and accelerations of the drones and their batteries were measured. The behavior of the drones and the batteries were considered based on the analysis results of the high-speed cameras. When the drones collided with the barrier, the batteries attached to the drones with snap-fit, rubber bands, and hook-and-loop fasteners separated from the drones. The separated batteries subsequently collided with the barrier. In the collision of the batteries and the barrier, the acceleration of the battery attached to the front of the drone by snap-fit was maximum. The acceleration was approximately 2.2 times larger than the acceleration given to the battery by the impact testing machine in the JIS standard (JIS C62133-2) that defines the test method for the safe operation of lithium secondary batteries used for portable devices. The damage conditions of batteries were presented and discussed from the viewpoint of the collision safety of batteries.

Background: The Sonoran Desert region, encompassing most of southern Arizona, has an extreme climate that is famous for dust storms known as haboobs. These storms lead to decreased visibility and potentially hazardous driving conditions. In this study we evaluate the relationship between haboob events and emergency department (ED) visits due to motor vehicle collisions (MVCs) in Phoenix, Arizona.Methods: This study is a retrospective analysis of MVC-related trauma presentations to Phoenix, AZ, hospitals before and following haboob dust storms. These events were identified from 2009–2017 primarily using Phoenix International Airport weather data. De-identified trauma data were obtained from the Arizona Department of Health Services (ADHS) Arizona State Trauma Registry (ASTR) from seven trauma centers within a 10-mile radius of the airport. We compared MVC-related trauma using six- and 24-hour windows before and following the onset of haboob events.Results: There were 31,133 MVC-related trauma encounters included from 2009–2017 and 111 haboob events meeting meteorological criteria during that period. There was a 17% decrease in MVC-related ED encounters in the six hours following haboob onset compared to before onset (235 vs 283, P = 0.04), with proportionally more injuries among males (P < 0.001) and higher mortality (P = 0.02). There was no difference in frequency of presentations (P = 0.82), demographics, or outcomes among the 24-hour pre-and post-haboob groups.Conclusion: Haboob dust storms in Phoenix, Arizona, are associated with a decrease in MVC-related injuries during the six-hour period following storm onset, likely indicating the success of public safety messaging efforts. Males made up a higher proportion of those injured during the storms, suggesting a target for future interventions. Future public-targeted weather-safety initiatives should be accompanied more closely by monitoring and evaluation efforts to assess for effectiveness.

Objective To reasonably evaluate the energy absorption reliability index of anti-climber devices, a reliability analysis method based on ISSSM (improved sinusoidal and surrogate model) is proposed. Method Firstly, a finite element model for anti-climber device collision is established. Secondly, the rationality of the finite element simulation model is verified based on the collision test data of the anti-climber device. Then, based on the principles of sum of sine function construction, the basic form of the force-displacement function for the anti-climber device collision process is clarified. According to the energy absorption consistency criterion, the anti-climber device energy absorption ISSSM is constructed. Combining reliability theory, a reliability analysis model for anti-climber device energy absorption is established. Finally, a specific model of anti-climber device is studied, and its energy absorption reliability index is evaluated. Result & Conclusion The constructed energy absorption ISSSM can reasonably reproduce the mechanical characteristics of the anti-climber device collision energy absorption process. When the coefficient of variation increases from 0.05 to 0.1, the energy absorption reliability index decreases from 3.07 to 1.53.

Statistical dependences of orbit parameters in four groups of sungrazing comets are studied. It is shown that the perihelia of comets of the Kreutz family are clustered around two planes (great circles of the celestial sphere). Numerical data on the observed bifurcation of perihelion distribution are provided. One of the planes basically coincides with the plane obtained by averaging orbit parameters Ω and i. The second plane with parameters Ωp = 77.7° and ip = 266.1° has an inclination of approximately 64° relative to the first plane. The distant nodes of cometary orbits relative to this plane are clustered at a distance of approximately 2 a.u. On the basis of the above, one of the authors hypothesizes that the comet group originates from the collision of a large comet with a meteoroid stream. This study examines some counterarguments expressed regarding this hypothesis. It is shown, based on a particular case, that the assumptions about the concentration of comet perihelia near one point and along two circles of the celestial sphere are quite compatible. The distribution of orbit inclinations relative to this plane is analyzed and a sharp maximum near 90° is noted. The maximum indicates that the parent body experienced lateral impacts of meteoroid bodies in all probability, which caused defragmentation of the former. New confirmations of the suggested hypothesis about the presence of another group of sungrazers have been found. It is assumed that the correlation dependence between the values of the perihelion parameters and ascending nodes of cometary orbits is of an evolutionary nature and is related to the group formation process. New relationships that concern the Meyer, Kracht, and Marsden groups are introduced. In particular, the authors have calculated the planes near which the cometary perihelia of these groups are concentrated. The example of the Meyer group illustrates the bifurcation of perihelia. [ABSTRACT FROM AUTHOR]

Roads have a multitude of direct negative effects on wildlife due to collisions and noise and play a prominent role in overall habitat fragmentation. For bats, landscape fragmentation by roads causes disturbance during nocturnal movements and road kill negatively affects local abundance and bat population dynamics. Mitigation measures such as wildlife crossings (green bridges) are among the proposed improvements intended to reduce the fragmentation impact of roads for many taxa, but their efficiency has rarely been tested for bats. In this study, we performed a control-impact analysis to assess the efficiency of two structures on the number of bat crossings by assessing their collision risk using an acoustic flight path reconstruction (AFPR) approach. We obtained data for 458 crossings for six bat taxa that showed how the number of bat crossings is significantly higher on green bridges than control sites for all species (pooled) and for two guilds — one with species with a low flight height and the other with a higher flight height. We also found that bat activity on either side of a green bridge is not a predictor of the true use of the bridge to cross roads. Considering these results, wildlife crossings can be envisaged as a mitigation measure to reduce impacts of road construction on bat movements. [ABSTRACT FROM AUTHOR]

The research work presented in this paper gives a comprehensive approach to the design and implementation of an innovative obstacle avoidance algorithm tailored for mobile robotic vehicles. The primary aim is to develop a robust system capable of effectively detecting and navigating around obstacles in real-time scenarios. The algorithm is constructed using MATLAB, leveraging its computational capabilities and extensive toolset for algorithm development and simulation. The methodology encompasses several key stages. Initially, sensor data acquisition is performed through various sensors integrated into the robotic platform, including but not limited to cameras, LiDAR, ultrasonic sensors, or a combination thereof. Subsequently, a systematic and multi-faceted approach is employed for obstacle detection, involving techniques such as image processing, depth perception, and sensor fusion. The detected obstacle information is then processed and integrated to generate a dynamic and adaptable avoidance strategy. This strategy accounts for the vehicle's kinematics, environmental constraints, and real-time feedback, allowing for agile and safe navigation in complex and dynamic environments. The algorithm's responsiveness is optimized through iterative testing and refinement, ensuring its reliability and efficiency in diverse scenarios. The algorithm's performance is evaluated through extensive simulation studies and practical experiments with the mobile robotic platform operating in controlled and real-world environments. Quantitative metrics, including obstacle detection accuracy, avoidance efficiency, and computational performance, are employed to assess and validate the algorithm's effectiveness. The outcomes of this research contribute to the advancement of obstacle avoidance methodologies for mobile robotics, offering insights into the development of adaptive and intelligent systems capable of navigating challenging terrains autonomously. The proposed algorithm demonstrates promising results in enhancing the autonomy and safety of mobile robotic vehicles, paving the way for applications in various fields, including but not limited to autonomous transportation, surveillance, and exploration. [ABSTRACT FROM AUTHOR]

This study aimed to examine the factors associated with pedestrian–vehicle collision hotspots involving seniors and children. For the empirical analysis, we first quantified street-level images of collision hotspots involving seniors and children and non-collision hotspots in the Seoul Metropolitan Area, Korea, using deep learning analysis. Thereafter, we examined the risk factors associated with collision hotspots through logistic analyses. This study has two major findings. First, the effects of risk factors (e.g. share of sky and green space) differ between collision hotspots involving seniors and children. Second, some pedestrian safety treatments (i.e. traffic lights and sidewalks) are positively associated with collision risks. The findings suggest that varied approaches to enhancing pedestrian safety among different age groups should be considered for more effective pedestrian safety interventions. In addition, the quality of pedestrian safety measures should be examined to improve pedestrian safety for seniors and children. [ABSTRACT FROM AUTHOR]

Rubber material is an excellent cushioning material in daily life and engineering applications. In this paper, the influence of rubber combination types and the corrugated surface roughness on cushioning performance are analyzed. By controlling the friction coefficients at different positions, the influence on the cushioning performance is also explored. Solving the numerical instability and energy nonconservation that are prone to occur in collisions is crucial for the accuracy of numerical simulation. The complexities of collision solution are overcome by separating nonlinear factors. The dynamics equation is derived according to the principle of virtual displacement, the geometric nonlinear problem of materials is described by the total Lagrangian formulation. Under the bipotential framework, the boundary nonlinear problem is solved based on the complete contact law. To reduce the solution cost and to improve the numerical accuracy, the prediction-correction step is used to solve the collision force. The bipotential coefficient is automatically updated with time steps, without the need for manual adjustment by users, achieving better convergence. Then, the collision force is substituted into the dynamic equation in the form of external load, which will not increase the degrees of freedom, and has better numerical robustness. In addition, the Newton–Raphson iterative method is embedded in the Tamma–Namburu scheme to solve the material nonlinearity problem and improve the numerical stability. Several numerical examples are presented to demonstrate the effectiveness of the proposed algorithm in the simulation of collision problems. Moreover, the proposed algorithm is proved to be stable and strictly satisfy the law of energy conservation/dissipation. Even for the corrugated surface structure with nonuniform friction, it can also better complete simulating the collision process. [ABSTRACT FROM AUTHOR]

Fences can reduce wildlife-vehicle collisions, but it is not always possible to fence over long distances, especially not in multi-functional landscapes. Side roads, driveways, and the need for access to agricultural fields all result in gaps in the fence. In some cases, wildlife guards or gates are installed at access points. However, gates usually require people to get in and out of their vehicle and they are often left open. Wildlife guards are typically only suited for low traffic speed, and while they can be a substantial barrier to ungulates, they are readily crossed by species with paws, including bears. Electrified barriers embedded in travel lanes can be a substantial barrier to both ungulates and bear species and while they can be suitable for higher traffic volume and speed, the costs are typically higher than for low volume and low speed roads. We explored the potential of low-cost electrified barriers to keep bears from accessing fenced road corridors at low traffic volume and low speed vehicle access points. As a first step, we conducted the study on private land at a melon patch that was a known attractant for black bears. We investigated the effectiveness of an electric fence and 5 different types of electrified barriers designed to keep black bears out of the melon patch. The electrified barriers included a swing gate, a standard bump-gate, a modified bump-gate with conductive netting, drive-over wires a few inches above the ground, and a drive-over mat. Trail cameras were installed at each access point to document approaching black bears and potential crossings into the melon patch. The swing gate, modified bump-gate, drive-over wires, and drive-over mat were an absolute (100%) or near absolute barrier (94.3%) for black bears while the standard bump-gate was a poor barrier (48.4%). Through a step-by-step process, the weak points of the electrified barriers at the vehicle access points and the electric fence around the melon patch were addressed. After addressing a weak point at a vehicle access point, the bears increasingly dug under the fence to enter the melon patch. However, eventually the melon patch became almost inaccessible to black bears. The number of black bears trying and succeeding to enter the melon patch at a particular location depended on how difficult it was to enter at other locations. This illustrates that fences and vehicle access points should be designed, operated, maintained, and monitored as a system rather than as individual features, regardless of whether the goal is to protect crops or to keep animals out of a fenced road corridor. The total number of black bear observations at the locations monitored with a trail camera, regardless of which side of the fence or electrified barriers the bears were on, was 95% lower in 2021 than in 2020. Combined with having no indication of a substantial drop in black bear population size from 2020 to 2021, this suggests that after the black bears were no longer able to enter the melon patch, they drastically reduced their presence in the immediate surroundings and reduced their effort to try and access the crop; the attraction of the melon patch and the habit of eating its melons was broken. [ABSTRACT FROM AUTHOR]

Offshore wind energy development (OWED), while a key strategy for reducing carbon emissions, has potential negative effects to wildlife that should be examined to inform decision making and adaptive management as the industry expands. We present a conceptual framework to guide the long-term study of potential effects to birds and bats from OWED. This framework includes a focus on exposure and vulnerability as key determinants of risk. For birds and bats that are exposed to OWED, there are three main effects of interest that may impact survival and productivity: 1) collision mortality, 2) behavioral responses, including avoidance, displacement, and attraction, and 3) habitat-mediated effects to prey populations. If these OWED effects cause changes in survival and/or breeding success (e.g., fitness), they have the potential for population-level consequences, including changes in population size and structure. Understanding the influence of ecological drivers on exposure and effect parameters can help to disentangle the potential impacts of OWED from other stressors. We use this theoretical framework to summarize existing relevant knowledge and identify current priority research questions (n=22) for the eastern United States, where largescale development of OWED is primarily in the planning and early construction phase. We also identify recommendations for study design and further prioritization of research topics. [ABSTRACT FROM AUTHOR]

Understanding the collision between kerosene droplets and coal particles in the bubble trailing vortex region is crucial for enhancing slurry conditioning. We found the area of the bubble trailing vortex region increased as the bubble size increased via the Fluent 6.3.26 software. A kerosene droplet velocity range of 0.074–0.106 m/s and a coal particle velocity range of 0.062–0.104 m/s were obtained if a bubble had a diameter of 0.3 mm. We employed a high‐speed motion acquisition system and observed the collision process, which was divided into two stages: Compression and Rebound. The critical motion distance increased as the kerosene droplet size increased, and sufficient kerosene droplet motion distance and enough kinetic energy normally resulted in a rebound phenomenon. The attenuation energy was almost positively linear to the initial energy, and the energy attenuation coefficient of the collision process was fitted to 0.626. Our results can provide valuable insight into mineral separation. [ABSTRACT FROM AUTHOR]

Assessing postural control is important for the assessment of motor function after concussion. Data used for postural control assessment typically do not take the sport played, age, or sex of the athlete into consideration. It is plausible these variables may be significant when making return-to-play decisions. This study used the BTrackS database to examine differences in postural control in athletes playing different types of sports and across sex and age. BTrackS data from 9093 high school to college-aged athletes (aged 14–22 years) were examined employing a One-way ANOVA with a post-hoc test to compare CoP path length between sport types. A moderation analysis was used to test interaction effects of sex and age on a CoP/BMI ratio. Significant differences were observed between sport types, F(3,9089) = 42.4, p <.001, η2 = 0.014. Post hoc tests indicated that collision (M = 25.0, SD = 7.6) sport athletes exhibited significantly higher CoP measures compared to the contact (M = 23.4, SD = 7.4), limited contact (M = 22.9, SD = 6.9), and non-contact (M = 23.0, SD = 7.4) athletes. There was no difference between other sport types (p >.20). A significant mean sex difference (Mmale = 0.924, Mfemale = 0.898, p <.001) and a quadratic association with age, (β = −0.042, p <.001) was observed. Further, magnitude of those age differences decreased with age (β = 0.011, p <.001). An interaction of age and sex was significant for linear (β = 0.020, p <.001) and quadratic terms (β = −0.006, p <.001). Athletes exhibited different postural control when the type of sport, age, and sex was taken into consideration. This data possess clinical significance as this suggests that normative postural control data for collision sport athletes should be derived from data based upon type of sport played, age, and sex of the athlete. • Over 9000 balance tests were analyzed, based on frequency and level of contact. • Balance data used for return-to-play decisions should be from similar sports. • Collision sports athletes display significantly different balance performance. [ABSTRACT FROM AUTHOR]

Concurrent occurrence of schwannoma and meningiomas are rare, and are found especially in association with neurofibromatosis type 2 (NF2). Occurrence of mixed tumor without the aforementioned conditions is extremely rare. We present three cases of mixed tumor in different locations, including two with NF2 and one without NF2. We analyse the relationship of mixed tumor with NF2 and its clinical implications. Presence of mixed schwannoma–meningioma should prompt screening for NF2. Thus aids in early diagnosis of unsuspected NF2 cases. We observed that irrespective of different locations, cases with NF2 showed frequent recurrence of schwannoma as compared to case who did not fit in the existing clinical criteria for NF2. Collision tumor and thereby NF2 mutations indicates the prognosis and recurrence of the tumor, thereby guides in deciding the management. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three stages of crustal thickening occurred in the DOB since the Neoproterozoic. • The thickest crust at ca. 210 Ma represents the cessation of ultradeep subduction. • The Late Archean crust thinning may be related to the onset of plate tectonics. The Dabie orogenic belt is characterized by widely distributed Mesozoic ultrahigh-pressure metamorphic rocks. Together with the Qinling orogenic belt, it constitutes one of the most important collisional orogens in eastern Asia. Because of intense continental subduction and collision during the Mesozoic and subsequent denudation, it remains controversial whether pre-Mesozoic convergent events happened in the region of the Dabie orogenic belt. In this study, we reconstruct the crustal thickness variation of the Dabie orogenic belt based on detrital zircon data. Results reveal three stages of crustal thickening at ca. 900-800 Ma, ca. 530-400 Ma, and ca. 250-210 Ma that are likely associated with three major convergent events that happened between the North and South China Blocks since the Neoproterozoic. The first thickening stage is possibly related to long-term subduction-accretion-collision processes along the northern margin of the South China Block. The second one corresponds to early Paleozoic ocean closure and the arc-continent collision that happened between the North and South China Blocks. The third one is a most significant thickening that represents the final collision between the North and South China Blocks during the Mesozoic. The turning point (ca. 210 Ma) of the crustal thickness curve represents the cessation of ultradeep subduction and constrains the completion of Mesozoic continental collision. Late Archean crustal thinning may be related to the onset of plate tectonics. Overall, the fluctuations of crustal thickness and detrital zircon age populations from sediments of the Dabie orogenic belt suggest interaction among Chinese continental blocks is consistent with the evolution of global supercontinent cycles. [ABSTRACT FROM AUTHOR]

Based on the discrete element method, this study has simulated the movement of materials in the plated barrel using EDEM software to investigate the effect of the impact medium with different particle sizes on the mechanical deposition plating. The simulation analyzed the interaction between five impact mediums with different particle sizes (2, 3, 4, 5, and 6 mm) and the base body while determining the particle size ratio of the impact medium. The rationality of the particle size ratio was verified by the simulation analysis of the interreaction of two groups of mixed particle size impact medium and the base body. The samples of mechanically deposited zinc coating were prepared. The average thickness, relative density, and average deviation of the coating were measured. The results show that When the particle size is 2 and 3 mm, the effective collision frequency of the materials is higher. When it is 3, 4, and 5 mm, the kinetic energy of collision between materials fluctuates evenly. When it is 4 and 5 mm, the collision contact force of the materials changes regularly. Consequently, the obtained particle size ratio (second group) is 2 mm 23%; 3 mm 23%; 4 mm 23%; 5 mm 27%; and 6 mm 4%. Compared with mixed impact media with 20% of each of the five particle sizes (first group), in the second group of assorted particle size simulation test, the collision frequency between materials is high. The contact force changes more regularly between materials. The average thickness, relative density, and average deviation of the mechanically deposited galvanized layer are consistent with the simulation results of the two groups of mixed particle sizes. The average thickness and relative density of the galvanized layer in the second group are higher, the average deviation is smaller, and the compactness and uniformity are the best. [ABSTRACT FROM AUTHOR]

The study of vulnerable road users (VRUs) behavior is key to designing and optimizing driving assistance systems, such as the autonomous emergency braking (AEB) system. These kinds of devices could help lower the VRU accident rate, which is of particular interest to cyclists, who are the subject of this research. To better understand cyclists' reaction patterns in frequently occurring collision scenarios in urban environments, this paper focuses on developing a virtual reality (VR) simulator for cyclists (VRBikeSim) that incorporates eye-tracking functionality. The braking and steering systems were calibrated by means of on-track tests with a sensorized bicycle in order to improve the accuracy of the bicycle virtual model. From the data obtained in the virtual tests, a battery of predictive models was built using supervised machine learning classifiers. All of them exhibited an accuracy higher than 85%, especially the K-Nearest Neighbors model. This model allowed us to obtain the best balance between the prediction of avoidance and collision cases, as well as enabling computationally lower times to be incorporated into the decision-making algorithm of an AEB system. [ABSTRACT FROM AUTHOR]

Vibratory finishing within restricted space is an effective way to finish the surface of complex cavities in an aero-engine integral casting casing, where the contact mechanism between the processing media and the rough surface is the nature for producing the processing effect. In this work, vibratory finishing was performed by semi-shading the workpiece, comparing the workpiece surface profile change with time for different vibration directions and processing positions, and height parameters and feature parameters evaluated the rough surface. The results show that the process of profile change on the workpiece mainly subjected to normal action is mainly the raising of valleys after profile peaks extrusion deformation and accompanied by the formation of finer peak-to-valleys. The workpiece subjected to tangential action reduces the surface roughness by filling the valleys after cutting the peak tips. The finishing mechanisms for rough surfaces can be summarized as collision, roll-pressing, and scratching. [ABSTRACT FROM AUTHOR]

Spherical parallel manipulators (SPMs) have promising industrial applications due to their strong mechanical performance. However, they face challenges such as singularity avoidance, tight tolerance manufacturing requirements, and the need for versatile and dexterous end-effector functionalities. Additionally, SPMs lack customizability due to singularity and collision issues. This work introduces a novel design principle that addresses these challenges by benchmarking two analytical methods: structural synthesis using screw theory and dimensional synthesis using dimensionless parameters. A proof of concept of a 2-DoF SPM that can operate within a cylindrical constraint and realize a full workspace without collision is presented. This design allows for adjustable reachable workspace at the end-effector, despite significant geometric constraints. These findings on mechanical design solutions provide customizability for SPMs, and a 3D model with an aspect ratio of 1/12 is presented and discussed for potential practical applications. Overall, it is identified that both a simulation using Recurdyn and inverse kinematic model show the desired movements at the moving platform with the maximum error of 0.0013°. [ABSTRACT FROM AUTHOR]

Vehicle safety on roadsides is vital for preventing collisions, controlling failures and accidents, and ensuring driver and passenger wellness. Finite Element Analysis (FEA) in vehicle safety relies on the vehicle's physical attributes for predicting and preventing collisions. This article introduces a Differential FEA (DFEA) model for predicting vehicle collisions regardless of the speed and direction for driver/ passenger safety. The proposed model induces a vehicle's speed, direction, and displacement from two perspectives: self and approaching vehicle. The collision probability with the trailing or persuading vehicle is calculated by distinguishing the forward and rear features. The differential calculus for the point of deviation and distance metrics are significantly estimated for a vehicle's front and rear ends. Such calculus generates a maximum and minimum possibility for self and approaching vehicle contact. This contact is further split based on the collision threshold; the threshold is determined using the safe distance between two vehicles for collision-less driving. The threshold exceeding vehicles are alerted for their change in direction/ speed through contact point (rear/front) differential derivatives. This ensures collision detection under fewer contact errors, leveraging the safety of the duo vehicles. [ABSTRACT FROM AUTHOR]

During the operation of the drill string, it displays a degree of flexibility. Simultaneously, its dynamic properties, influenced by complex stress conditions, manifest nonlinearity and uncertainty. A comprehensive investigation into the dynamics of flexible drill strings is imperative for deep well drilling. This paper presents a model that simulates random interactions between a flexible drill string and the borehole wall, simplifying the actual drill string model using analogous principles. Dynamic simulation software is utilized for analysis, and an indoor experimental setup has been established. The results reveal that with a constant weight on bit (WOB), higher drill string rotational speeds correlate with increased susceptibility to buckling deformation. Additionally, the critical time for deformation onset exhibits a nearly linear relationship with rotational speed. Maintaining a constant rotational speed, an increase in WOB enhances the likelihood of buckling deformation. The experimental findings suggest a correlation between the drill string’s rotation frequency and the WOB.

Relevance. Understanding the mechanisms of liquid droplets interaction with each other is important for many industrial and technical applications related to solving a range of problems like slag removal in a high-temperature environment, obtaining components of the desired fraction in the food industry, etc. Aim. Establishment of the main patterns of suspension droplets interaction in a gas-air environment with temperature variation. Methods. Using shadow high-speed video recording, the main patterns of the binary collision of suspensions droplets were determined. The paper introduces the results of experimental studies of the characteristics of collisions of droplets of coal-water suspensions in a gas-air environment with a temperature of 90–120°C. Parameters of the generated droplets: radius 1.0–2.2 mm, velocity 0.5–2.0 m/s. Results and conclusions. The authors have determined the modes of collision of droplets of suspensions (coagulation and separation) and the main characteristics of secondary fragments and constructed the maps of the modes of interaction of drops of suspensions with each other when varying the concentration of solid particles in the suspension, the temperature of the gas-air environment and the time the target drop spent in a gas-air environment with an elevated temperature. The conditions were established for the coagulation of droplets, as well as their intensive secondary grinding to intensify their drying, ignition and combustion in boiler furnaces. It was established that an increase in the temperature of the gas-air environment leads to a significant change in the size and properties of droplets, as well as to the occurrence of oscillatory phenomena in the system. It is substantiated that collision of droplets of suspensions in a gas-air environment with elevated temperature is complex and multi-parametric. Its characteristics depend on a combination of factors (surface tension and liquid viscosity, size and shape of droplets, speed of their movement, density and viscosity of gas-air environment). The authors obtained mathematical expressions to describe the boundaries of the modes of the studied processes and schemes for using the results obtained in order to increase the efficiency of the corresponding technological processes.

Purpose: Tackling is a fundamental skill in collision sports such as rugby league. Given the complexity of tackling and multitude of strength and power variables available for analysis, this study aimed to predict tackle outcomes in professional rugby league based on strength and power principal components (PCs). Methods: Twenty-eight rugby league players participated in this study. Maximal strength was assessed via 1 repetition maximum on the back squat, bench press, and bench pull. Lower-body vertical and horizontal power were evaluated using a countermovement jump and standing broad jump. A postmatch analysis of 5 National Rugby League matches was conducted to examine tackling outcomes. PC analysis was performed on the strength and power assessments. The first PCs were retained in each analysis, and a series of Spearman rank-order correlations were conducted between the tackle outcomes and the retained PCs. The PCs significantly related to tackle outcomes were included in the multiple regression analyses to estimate their effect on tackle outcomes. Results: Strength PC was a significant predictor of play-the-ball speed in attack, accounting for 54% of the variance. Countermovement jump PC was a significant predictor of postcontact meters, explaining 19% of the variance. Conclusions: These findings demonstrate that a range of tackle outcomes may be predicted from strength and power components. The coaching staff may choose to develop programs and testing designed to focus on these components, which may further develop players' tackle outcomes during competition. [ABSTRACT FROM AUTHOR]

To address vibration issues in the operation of a lift-type power catwalk, dynamic analysis was conducted using ADAMS 2020 software. The analysis revealed that the vibrations originate from collisions that occur during the transition from the translation to the climbing phase. A quantitative vibration model was developed using the work–energy theorem, incorporating the coefficient of restitution. Based on this model, a composite disturbance rejection control law was designed, integrating sliding-mode speed planning with active disturbance rejection speed tracking. The MATLAB 2022b/Simulink simulations demonstrated that the ADRC strategy outperforms PID and DDPG control algorithms in terms of robustness. Co-simulation with ADAMS and MATLAB/Simulink confirmed the effectiveness of sliding mode speed planning, resulting in a 13.54% increase in the transport efficiency of lift-type power catwalks for drill pipes. Additionally, the oscillation of the output speed of the electro-hydraulic servo system at the collision point was reduced by 300% and the displacement, velocity, and acceleration fluctuations in the catwalk’s mechanical system were reduced by 85%, 75%, and 90%, respectively. The experiments on a lift-type power catwalk prototype confirmed that the proposed vibration suppression strategy effectively reduces vibrations.

Herein, a method for detecting microplastics in water using single-entity electrochemistry is presented, with a focus on the interaction between microplastics in aqueous solution and the surface of an ultramicroelectrode (UME). Polystyrene and polypropylene, two commonly used plastics that were ground and dispersed in aqueous solution, served as the detection target materials. The collisional contact of microplastics with the UME was transduced into a discernible signal. To detect microplastics in solution using an UME, redox species (e.g., ferrocyanide) were continuously oxidized at the electrode, and the resulting steady-state current was monitored. Collisional contact followed by adsorption of microplastics on the UME disturbed the diffusional flux of redox species, resulting in an immediate change in the steady-state current. Detection sensitivity was further enhanced by optimizing the electrolyte composition to induce a migration effect. COMSOL Multiphysics simulations were employed to analyze the magnitude of the current changes as a function of microplastic size. The size distribution obtained from the simulations closely matched measurements from dynamic light scattering (DLS).

Firstly, in this study, we utilize the high-order element model (truss link model) simulation method in OpenSees (3.7.0) software and verify the feasibility of this method by comparing it with the shaking table test. Secondly, the structural dynamic response of adjacent structures with different performance levels, spacing, and layout forms under large earthquakes is analyzed, and the corresponding structural failure probability is studied. Furthermore, the life distribution within the design service life of the structure is predicted according to the nonparametric Kaplan–Meier estimation model. Finally, the reliability of adjacent structures is evaluated by using the joint engineering demand parameters. The analysis method of replacing the theoretical analysis based on engineering experience and certainty in the current specification with probability analysis is proposed, which provides a more reliable theoretical basis for decision-making regarding the reinforcement, maintenance, or demolition of structures in the later stage.

Long-Range Wide-Area Network (LoRaWAN) technology offers efficient connectivity for numerous end devices over a wide coverage area in the Internet of Things (IoT) network, enabling the exchange of data over the Internet between even the most minor Internet-connected devices and systems. One of LoRaWAN’s hallmark features is the Adaptive Data Rate (ADR) algorithm. ADR is a resource allocation function which dynamically adjusts the network’s data rate, airtime, and energy dissipation to optimise its performance. The allocation of spreading factors plays a critical function in defining the throughput of the end device and its robustness to interference. However, in practical deployments, LoRaWAN networks experience considerable interference, severely affecting the packet delivery ratio, energy utilisation, and general network performance. To address this, we present a novel ADR framework, SSFIR-ADR, which utilises randomised spreading factor allocation to minimise energy consumption and packet collisions while maintaining optimal network performance. We implement a LoRa network composed of a single gateway that connects loads of end nodes to a network server. In terms of energy use, packet delivery rate, and interference rate (IR), our simulation implementation does better than LoRaWAN’s legacy ADR scheme for a range of application data intervals.

A collision tumor is a neoplastic lesion comprised of two or more tumors consisting of distinct cell populations in the concurrent location. Multiple skin neoplasms at one site (MUSK IN A NEST) is a term recently coined to describe two or more cutaneous benign or malignant tumors occurring at the same anatomic site. In retrospective studies, seborrheic keratosis and cutaneous amyloidosis have both individually been documented as a component of a MUSK IN A NEST. This report describes a 42-year-old woman who presented with a pruritic skin condition on her arms and legs of 13 years' duration. Skin biopsy results showed epidermal hyperplasia with hyperkeratosis, hyperpigmentation of the basal layer with mild acanthosis, and evidence of amyloid deposition in the papillary dermis. Based on the clinical presentation and pathology findings, a concurrent diagnosis of macular seborrheic keratosis and lichen amyloidosis was established. A MUSK IN A NEST consisting of a macular seborrheic keratosis and lichen amyloidosis is likely a more common occurrence than implied by the paucity of published cases of this phenomenon.

Abstract The Alpine orogeny is a consequence of the collision of Africa with Eurasia, which eliminated the Western Tethys Ocean. Processes similar to those that would have taken place early in that collision can today be seen operating in the islands of the Indo-Pacific gateway between Southeast Asia and Australia and have the potential to offer insights into the beginnings of orogenesis in the Alps. Studies of the gateway area emphasise the importance of the impact on subduction zones of topography on the downgoing plate, and of the effects of flows in the asthenosphere on lithosphere tectonics.

The paper presents the experimental research findings for the patterns of collisions of water droplets with pressed tableted samples used as substrates and with small particles of a pyrolyzing solid fuel. Brown coal samples were used. Droplet-substrate interactions were studied when varying the droplet diameter in the range from 1 to 4 mm and velocity from 0.5 to 4 m/s. That corresponded to the Weber number range of 7–830. The coal tablet surface temperature was varied from 20 to 700 °C. In the interactions of water droplets (0.7–1.5 mm in diameter, pre-collision velocity from 1 to 3 m/s) with coal particles (with a size of 0.2–1 mm, pre-collision velocity 0.7–2 m/s), the temperature of the latter was varied in the range of 330–480 °C. The following regimes of the interaction of droplets with solid particles during chemical reactions and phase transformations were distinguished: spreading/agglomeration and break-up/separation. Differences in the characteristics of the interaction of water droplets with coal particles at varying temperatures were identified. Droplet-particle interaction regime maps for B(We), We(Oh) and We(Ca) were constructed. The collision regime boundaries were described using fitted curves that can be utilized to develop the existing mathematical models of droplet-particle collisions in gas. It was established that the gaseous volatile production in coal pyrolysis has a modest effect on the regimes and characteristics of the droplet destruction in the temperature range under consideration (20–700 °C).

The problem of hyperbasites origin is one of the widely discussed topics in geology. This is because they often appear when no expected. Their development does not correspond to the general regularities of the geological complexes’ development. Therefore, when problematic instances of hyperbasites appear, discussion is inevitable. This is due to the imperfections of existing concepts, which are not without flaws. The essence of this concept lies in the fact that during the rotation of the Earth around its axis, geodynamic forces are formed. The hyperbasites complex by its nature belongs to deep igneous formations formed at the initial stage of development of volcano-plutonic processes, where the composition of magmatic products was not subject to decomposition. In general, the origin of igneous rocks is associated with deep anomalous processes, which were formed under the influence of geodynamic forces, where decompression of mantle matter occurs, causing a catastrophic increase in the volume of mantle matter, as well as the associated development of volcanoplutonic processes. Hyperbasites are formed both in divergent and convergent zones of the Earth’s crust. The main factor for their formation is high pressure – deep thermodynamic conditions, where there are no favorable thermodynamic conditions for the complete separation of magmatic melts by composition. The emergence of hypermafic rocks on the surface is associated with geotectonic or denudation processes. Denudation processes can expose only those hypermafic formations that are located at the site of formation. These zones include ancient platforms, sheets, terranes, etc., which were cut by deep erosion processes. As for those hyperbasic formations that are classified as alpinotype hyperbasites, they were moved to the structure of the Alps-Himalayan folded zone from the basement with a collision with subsequent geotectonic processes, where they formed in the bed of the Paleotethys Ocean, both in the process of divergence and convergence. The noted pattern of formation and the mechanism of formation of alpine-type hyperbasites clearly corresponds to the patterns of development of geodynamic forces in the face of the Earth, also with natural laws, which are the main factors in the evolution of the Earth’s crust. From the standpoint of KDEZK, the origin, mechanism of formation, as well as the form of distribution of alpinotype hypermafic rocks of the Lesser Caucasus occurred in the Paleotethys bed, under different thermodynamic conditions and at depths. Further, as a result of the collision, it participated in the formation of folded zones of the Lesser Caucasus. Within the Lesser Caucasus, two genetic types of hypermafic rocks are exposed. Some of them correspond to the convergent zone of the Tethys paleocean, while others correspond to divergent zones. In terms of ore content, the most promising are those hypermafic rocks that are genetically related to convergent zones.

Objective: Aiming at the problem that strawberry quality was easy to be damaged under impact in processing process. Methods: The relationship among impact energy loss, internal stress and impact damage of strawberry during impact was studied by display dynamics simulation method. The impact of impact parameters on damage degree and sensitivity was analyzed by response surface method. Results: When the strawberry collides with the steel plate at 23 ms, the ratio of strawberry damage volume reached the maximum (7.83%), and at the same time, the impact energy loss (95.60 mJ) and internal stress (0.238 4 MPa) both reached their maximum values. The error of collision simulation results was less than 5.0%, and the simulation method was reliable. Conclusion: The dynamic response of internal stress in strawberry is caused by the change of impact energy, which determines the impact damage degree. The influencing factors of fruit damage sensitivity were: contact material ＞ impact velocity ＞ impact angle.

In the 60s, the Hellenic belt was taken as the “Geosyncline model”. Here we take a modern look at this Hellenic/Aegean region which as a concentrate encompasses all the main geodynamic processes known in orogens. This region documents the fundamental characteristics of the geodynamic processes related to mountain building, namely continental rifting, oceanic spreading, oceanic then continental subduction, collision i.e., closure of oceanic basins. In particular, the Mesozoic obduction events in northern Hellenides, and the effects of a still ongoing major extension linked to the active subduction under the Aegean domain.

Offshore wind energy development (OWED), while a key strategy for reducing carbon emissions, has potential negative effects to wildlife that should be examined to inform decision making and adaptive management as the industry expands. We present a conceptual framework to guide the long-term study of potential effects to birds and bats from OWED. This framework includes a focus on exposure and vulnerability as key determinants of risk. For birds and bats that are exposed to OWED, there are three main effects of interest that may impact survival and productivity: 1) collision mortality, 2) behavioral responses, including avoidance, displacement, and attraction, and 3) habitat-mediated effects to prey populations. If these OWED effects cause changes in survival and/or breeding success (e.g., fitness), they have the potential for population-level consequences, including changes in population size and structure. Understanding the influence of ecological drivers on exposure and effect parameters can help to disentangle the potential impacts of OWED from other stressors. We use this theoretical framework to summarize existing relevant knowledge and identify current priority research questions (n=22) for the eastern United States, where large-scale development of OWED is primarily in the planning and early construction phase. We also identify recommendations for study design and further prioritization of research topics.

Introduction: Offshore wind energy development (OWED) has been identified as a major contributor to the aspired growth in Norwegian renewable energy production. Spatially explicit vulnerability assessments are necessary to select sites that minimize the harm to biodiversity, including seabird populations. Distributional data of seabirds in remote areas are scarce, and to identify vulnerable areas, species, and seasons it is necessary to combine data sets and knowledge from different sources. Methods: In this study, we combined seabird tracking data, data from dedicated coastal and seabird at-sea surveys, and presence-only data from citizen science databases to develop habitat suitability maps for 55 seabird species in four seasons throughout the Norwegian exclusive economic zone; in total 1 million km2 in the Northeast Atlantic. The habitat suitability maps were combined with species-specific vulnerability indicators to yield maps of seabird vulnerability to offshore wind farms (OWFs). The resulting map product can be used to identify the relative vulnerability of areas prospected for OWED with respect to seabird collision and habitat displacement. More detailed assessments can be done by splitting the spatial indicators into seasonal and species-specific components. Results and discussion: Associated with higher diversity of seabirds near the coast, the cumulative vulnerability indicator showed a strong declining gradient from the coast to offshore waters while the differences in vulnerability between ocean areas and seasons were negligible. Although the present map product represents the best currently available knowledge, the indicators are associated with complex uncertainties related to known and unknown sampling biases. The indicators should therefore be used cautiously, they should be updated regularly as more data become available, and we recommend that more detailed environmental impact assessments based on dedicated seabird surveys, tracking of birds from potentially affected populations and population viability analyses are conducted in areas ultimately selected for OWED. [ABSTRACT FROM AUTHOR]

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]

A method of constructing a quantum hash function (QHF) based on continuous-time quantum walk is proposed, in which the time of quantum walk is controlled by the binary string message, namely, a binary string message as the input of the constructed QHF and the probability value of finally walking to the nodes on the cycle is used as the output of the QHF. Numerical simulation and performance analysis show that our QHF has obvious advantages in the efficiency of the QHF compared with the existing QHF based on the discrete-time quantum walk, that is, the efficiency of our scheme is nearly 4 times faster in computing the hash value of the same size file compared with the most efficient scheme. Besides, the QHF has also better collision resistance compared with the existing QHF based on the discrete-time quantum walk. [ABSTRACT FROM AUTHOR]

The mechanoreception system in bionic micro air vehicles, akin to insect sensory neurons, handles internal and external stimulus information. However, current onboard mechanoreception methods add weight and necessitate additional power. Employing the embodied energy design paradigm, a lightweight intelligent membranous wing is proposed, mimicking the scarab beetle's hindwing morphology and kinematics. This wing serves multiple functions, including aerodynamic load‐bearing, flight piezo‐mechanoreception, and power supply. The beetle's semi‐tubular costa structure is replicated, featuring a compliant leading edge for upstroke aerodynamic load resistance. Inspired by beetle hindwing veins and membranes, the bionic wing with three membranous fields: anal, medial, and apical, using heat lamination of multilayer materials is fabricated. The bionic wing's aerodynamic performance closely mirrors that of a real beetle hindwing, enabling various flight maneuvers and validating its real‐flight potential. As a piezo‐mechanoreception receptor for micro air vehicles, the bionic intelligent wing senses flapping frequency, wing deformations, and collisions through voltage signals from piezoelectric materials in the three membranous fields. Energy harvested from flapping‐wing motion powers onboard light intensity and ultraviolet sensors for mobile 3D environmental monitoring. This integration of aerodynamics, mechanoreception, and power supply via embodied flapping energy offers a novel approach for designing future intelligent flapping‐wing micro air vehicles. [ABSTRACT FROM AUTHOR]

The Central Africa Orogenic Belt (CAOB) and the Transaharan and Sergipano belts form a major West Gondwana suturing orogen affected by D1–D4 compressional deformation. Microstructural observations, mineral chemistry, zircon, and titanite laser ablation ICP-MS U-Pb dating, and biotite, muscovite, and K-feldspar 40Ar-39Ar age data are used to constrain the timing of rocks formation and D1–D4 events in the Yaoundé Domain of the CAOB, as well as characterize the Neoproterozoic-Cambrian transition. The Yaoundé Domain rocks were deposited on a pre-Neoproterozoic structure that was overprinted by a c. 1000–700 Ma mega arc/back-arc system and related Tonian to Ediacaran magmatism. Older U-Pb dates (1000 up to 2700 Ma) are inheritance from a pre-existing crust. The D1–D4 compressional events relate to the inversion of the c. 1000–700 Ma mega-rift system. New dates at c. 700 Ma, c. 630 Ma, c. 580–555 Ma constrain the timing of D1, D2, D3+D4, respectively. The peak of accompanying metamorphism occurred at 614 ± 4 Ma during D2. This was followed by a c. 115 Ma period of deformation-driven crustal exhumation and cooling that extended into the Cambrian. New data document short episodes of rapid denudation and cooling (up to 0.9 km/Ma and 40°C/Ma at c. 578 Ma in gneiss and up to 5 km/Ma and >125°C/Ma at c. 555 Ma in micaschist). It is proposed that the CAOB and correlative belts are parts of the orogenic hinterland formed from accretion and collision between the West African Craton and the Sahara Metacraton precursor. The correlated belts appear to represent the result of a protracted tectono-metamorphic and magmatic process that started in late Mesoproterozoic (c. 1167 Ma) and continued through the Neoproterozoic to the Cambrian (c. 500 Ma). [ABSTRACT FROM AUTHOR]

One important area of study in cognitive radio ad hoc networks is multi-channel path scheduling. Cognitive radio networks have trouble communicating and using the spectrum effectively because of weather and dispersion. Optimizing multichannel path scheduling enhances network performance and reliability in a cognitive radio ad hoc net. The Optimizing Multichannel Path Scheduling (OMPS) model methodically tackles various scheduling problems. For the OMPS model, this domain is new. It effectively resolves multichannel path scheduling. The computer method used in the study is called Differential Evolution. During optimization, several factors are carefully considered, including Channel Fade Margin, Cross-Correlation and Coherence Time, Spectral Efficiency, Interference Level, Power Consumption, Retransmission Rate, Access Probability, and Propagation Delay. To increase the scheduling efficiency of the DE algorithm, many steps are meticulously planned: initialization, mutation, crossover, fitness evaluation, selection for iteration evolution, and termination. Latency, Packet Delivery Ratio (PDR), Spectrum Utilization, Interference Level, Energy Efficiency, and Established Path Success Rate are all assessed by the OMPS model. These indicators assess the effectiveness and dependability of the network. OMPS performs better in crucial simulations than the existing model. The demonstration demonstrates decreased latency for real-time applications, greater packet delivery ratios (PDRs), improved spectrum efficiency, channel interference, energy efficiency, and connection formation odds, as well as increased throughput that enhances network resource utilization. To do this, a variety of multichannel path scheduling situations are simulated. [ABSTRACT FROM AUTHOR]

In the fields of autonomous navigation and vehicle safety, accurately predicting potential collision field points between moving objects is a significant challenge. A novel computing technique to enhance trajectory interception analysis is presented in this paper. Our objective is to develop a field model that can accurately forecast collision zones, improving road transportation safety and the use of autonomous cars. Our main contribution is a binary classification model called PCSMO (Prediction of Collision Scope between Moving Objects), which is based on zero-shot learning. Gann angles, which are typically 45 degrees, are used to analyze the trajectories of moving objects. This method is inspired by GANN (Gann Angle Numeric Nomenclature). Compared to earlier techniques, this model more accurately identifies potential collision collision interception zones. The technique computes Gann angles for trajectory analysis and extracts GPS coordinates of moving objects from video data using OpenCV. It offers a more sophisticated comprehension of object movement patterns and points of interception. To assess the precision, recall, F1-score, and prediction accuracy of our model, we employ 10-fold cross-validation. Comparing the PCSMO model to existing models, these metrics demonstrate how well the PCSMO model predicts potential collision zones. Our approach, we discovered, enhances trajectory analysis--a critical component of safer autonomous navigation systems. With potential applications in autonomous vehicle and UAV safety, the PCSMO model improves field interception classification. [ABSTRACT FROM AUTHOR]