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Abstract Natural disaster management approach establishes stages of prevention, preparation, response, and recovery. With the Internet of Things (IoT), Bigdata, Business Intelligence, and other Information Communication Technologies, data can be gathered to support decisions in stages of the response to natural disaster events. In biological natural disasters, the ICTs can also support efforts to promote social distancing, public health, and economic monitoring to face the threads. São Paulo state used IoT in scenarios to face COVID‐19, such as monitoring vehicular interurban mobility, social distancing, and economic activity. Frameworks, strategies, data views, and use cases are presented to support the decision‐making process to face this biological natural disaster. The data‐driven approach supports several purposes, including the communication of social distancing indices, economic recovery, the progression of contagion, and deaths. It also played a pivotal role in fostering transparency initiatives for society and supporting the crisis committee by facilitating situational analyses, and this approach became standard practice for pandemic response. Studies and innovative visualisation perspectives have produced positive outcomes, guiding the decision‐making process through data analysis. Noteworthy use cases were interurban traffic fence monitoring; mapping of virus spreading; tracking the economic impact concerning recovery plans; and, evaluating the effectiveness of public policies.

Abstract With the recent advances in smartphones and Internet technologies, ride‐hailing services (such as Uber and Didi) have emerged and changed the travel modes that residents use. An important issue within this area is how ride‐hailing services influence public transit usage. The majority of the research regarding this topic has focused on situations in large cities and has not reached a unanimous consensus among scholars. In particular, the role of ride‐hailing services in small‐ and medium‐sized cities may be different from the role of these services in large cities. In this paper, we choose 22 small‐ and medium‐sized cities in China as samples with a research time window spanning from 2011 to 2016 to examine the impact of the introduction of ride‐hailing services on public transit usage. The results of the synthetic control method, as well as other robustness checks, show that (1) the introduction of ride‐hailing services to China's small‐ and medium‐sized cities significantly increases public transit usage; (2) the effect of the introduction of ride‐hailing services on public transit usage in small‐ and medium‐sized cities is “proactive” for approximately 1 year; and (3) the positive effect of ride‐hailing services on public transit usage in small‐ and medium‐sized cities weakens over time. This study enriches the literature on the impact of ride‐hailing services on the urban transportation system by specifically taking small‐ and medium‐sized cities as the research scope. The above findings are of great significance to the urban transport department's formulation of ride‐hailing policies and the operation layout of public transit operators in small‐ and medium‐sized cities.

Abstract Advanced Driver Assistance Systems (ADAS) have gained substantial attention in recent years. However, the integration mechanism of multiple functions within ADAS remains unexplored, and the full potential of its functionality remains underutilised. This paper presents a novel multi‐functional integrated High‐level Automated Driving Assistance System that combines the Cruise Control (CC), Adaptive Cruise Control (ACC), Automated Emergency Brake (AEB), and Automated Lane Change (ALC) functions. The presented system utilises a hierarchical framework. The extension multi‐mode switch strategy is established as the superior module and the Event‐Triggered Model Predictive Controller (ETMPC) is designed as the inferior controller. The CC, ACC, and ALC functions are effectively utilised to enhance traffic efficiency, while the AEB function ensures driving safety. To address the time constraints of conventional Model Predictive Control, an event‐trigger mechanism is proposed to reduce computational load. Simulations are conducted using the CarSim and Matlab platforms. The study results demonstrate significant improvements in both safety and traffic efficiency compared to conventional ADAS strategies. Furthermore, the proposed ETMPC method significantly reduces the frequency of solving Optimisation Problems and decreases online computation costs.

Abstract Fixed cycle traffic lights primarily regulate road traffic, in which traffic light control systems are for specific lanes or crossings in urban areas. Also, not being appropriately installed can prolong the congestion delay and unnecessarily long wait times for crossing intersections, which can cause emergency vehicles to become stuck at intersections. Adaptive signal timing management technique that is more computationally viable than current fixed cycle signal control systems and can improve network‐wide traffic operations by reducing traffic delay and energy consumption. Even though specific adaptive control systems exist, there is no mechanism to communicate with emergency vehicles, which is crucial for smart cities. Motivated by this problem, a novel framework, Emergency Vehicle Adaptive Traffic Light (EVATL), is proposed for smart cities where an adaptive mode of operation for traffic lights is employed with emergency vehicle communication, improving their functioning and reducing overall congestion delay. EVATL detects emergency vehicle location using GPS with the Internet of Things(IoT), which integrates with traffic signals and works adaptively according to vehicle density at the traffic signal using YOLOv8. So, the primary goal of the proposed EVATL is to prioritise an emergency vehicle while simultaneously integrating adaptive traffic signals for smart cities. A GUI is developed for evaluating the proposed model by creating different scenarios for an adaptive traffic light and emergency vehicle communication. While analysing the simulation results of the proposed model EVATL, a clear improvement can be seen in the wait time of vehicles at a traffic light with the timely detection of an emergency vehicle at a set distance.

Neural ordinary differential equations have emerged as a natural tool for supervised learning from a control perspective, yet a complete understanding of the role played by their architecture remains elusive. In this work, we examine the interplay between the width p and the number of transitions between layers L (corresponding to a depth of L + 1). Specifically, we construct explicit controls interpolating either a finite dataset D , comprising N pairs of points in R d , or two probability measures within a Wasserstein error margin ɛ > 0. Our findings reveal a balancing trade-off between p and L , with L scaling as 1 + O (N / p) for data interpolation, and as 1 + O p − 1 + (1 + p) − 1 ɛ − d for measures. In the high-dimensional and wide setting where d , p > N , our result can be refined to achieve L = 0. This naturally raises the problem of data interpolation in the autonomous regime, characterized by L = 0. We adopt two alternative approaches: either controlling in a probabilistic sense, or by relaxing the target condition. In the first case, when p = N we develop an inductive control strategy based on a separability assumption whose probability increases with d. In the second one, we establish an explicit error decay rate with respect to p which results from applying a universal approximation theorem to a custom-built Lipschitz vector field interpolating D. • Understanding neural ODE architectures is key for supervised learning via control. • Interpolation constructively attained, showing trade-off between depth and width. • Explicit error decay for autonomous, wide enough models via universal approximation. • In high dimensions, the required width scales with the size of the dataset. • Probability measures are interpolated with arbitrarily small Wasserstein-q error. [ABSTRACT FROM AUTHOR]

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The control of evolution of flow and heat transfer in melt pool is a key concern and hot topic to improve the produce quality, e.g. fissure and roughness, during the additive manufacture process. Researchers focus on controlling the evolution of melt pool by changing energy balance in melt pool. However, the momentum drive is seldom presented in literatures but fully necessary to further improve the control efficiency. Therefore, a promising magnetic force source is introduced to investigate the controlling effect on melt pool evolution. Based on a developed and validated laser melt pool model, the evolution results of three different magnetic field arrangements and intensities are obtained and analysed compared with that without magnetic force. In addition, the surface shrink characteristics during quenching process are studied to further evaluate the benefit of the added source. Results show that the melt pool evolution is significantly affected by the additional magnetic force. The increasing downward y-component force promotes the transport in melt pool which makes the surface deformation larger, as well as the melt pool dimension. Inversely, with the increase of x-component force, both the surface deformation and the melt pool dimension gradually decrease due to the induced transport limitation. During quenching process, the surface roughness is continuously reduced with a certain increase of the magnetic intensity caused by the increased melt pool duration and slightly vigorous surface flow. However, the improvement effectiveness becomes bad as the magnetic force exceeds a critical value owing to the increased shrink instability. [ABSTRACT FROM AUTHOR]

The high activation barrier of the C-H bond in methane, combined with the high propensity of methanol and other liquid oxygenates toward overoxidation to CO 2 , have historically posed significant scientific and industrial challenges to the selective and direct conversion of methane to energy-dense fuels and chemical feedstocks. Here, we report a unique core-shell nanostructured photocatalyst, silica encapsulated TiO 2 decorated with AuPd nanoparticles (TiO 2 @SiO 2 -AuPd), that prevents methanol overoxidation on its surface and possesses high selectivity and yield of oxygenates even at high UV intensity. This room-temperature approach achieves high selectivity for oxygenates (94.5%) with a total oxygenate yield of 15.4 mmol/g cat ·h at 9.65 bar total pressure of CH 4 and O 2 . The working principles of this core-shell photocatalyst were also systematically investigated. This design concept was further demonstrated to be generalizable for the selective oxidation of other alkanes.

Abstract: A novel technique for evaluating the relative inhibition effectiveness of different anti-scalants is presented. The technique is based on the ability of anti-scalants to modify the scale deposition mechanism from mass transfer control to surface control. A rotating cylinder system which is known to provide well controlled mass transfer conditions is used to determine the scaling rate of a supersaturated solution dosed with various feed concentrations of an anti-scalant. Mass transfer conditions were characterized by turbulent flow at hydrodynamically smooth surface. In the absence of an anti-scalant, scale deposition is mass transfer controlled and scaling rate increases with rotation speed. With sufficient anti-scalant dosage, precipitation is modified to surface control and rotation speed has no effect on the scale deposition rate. Determination of the critical anti-scalant dosage enabling surface controlled precipitation provides a sensitive technique for comparing the relative effectiveness of different anti-scalants. [Copyright &y& Elsevier]

In this paper, transport control and synchronization are investigated between two periodically driven non-identical, inertial ratchets that are able to exhibit directed transport. One of the two ratchets is acting as a drive system, while the other one represents the response system. Based on the Lyapunov stability theorem, the essential conditions, under which the error nonlinear system is transformed into an equivalent passive system and globally asymptotically stabilized at equilibrium points, are established. With these results, synchronization, not only between two non-identical ratchets with known parameters but also between two different uncertain ratchets, are realized via adaptive passive controllers and parameter update algorithm. The direction of transporting particles can be dominated along expected one and it is useful to control the motion of tiny particles, ratchetlike devices in nanoscience. [ABSTRACT FROM AUTHOR]

The battery charger and the dc-dc converter can be combined in a single unit with the three-port converter topology. In the three-port converter, one port is idling, while the other two are operating actively. To block power flowing into an idling port, a virtual isolation scheme is proposed. It is also illustrated by a phase analysis. Effectiveness of the proposed isolation scheme is verified by simulation and experimental results. [ABSTRACT FROM AUTHOR]

Abstract: Scientific datasets of large volumes generated by next-generation computational sciences need to be transferred and processed for remote visualization and distributed collaboration among a geographically dispersed team of scientists. Parallel visualization using high-performance computing facilities is a typical approach to processing such increasingly large datasets. We propose an optimized image compositing scheme with linear pipeline and adaptive transport to support efficient image delivery to a remote client. The proposed scheme arranges an arbitrary number of parallel processors within a cluster in a linear order and divides the image into a carefully selected number of segments, which flow through the linear in-cluster pipeline and wide-area networks to the remote client consecutively. We analytically determine the segment size that minimizes the final image display time and derive the conditions where the proposed image compositing and delivery scheme outperforms the traditional schemes including the binary swap algorithm. In order to match the transport throughput for image delivery over wide-area networks to the pipelining rate for image compositing within the cluster, we design a class of transport protocols using stochastic approximation methods that are able to stabilize the data flow at a target rate. The experimental results from remote visualization of large-scale scientific datasets justify the correctness of our theoretical analysis and illustrate the superior performances of the proposed method. [Copyright &y& Elsevier]

For logistics centers the disposition and dispatch of goods has reached a high standard of automation. However, the trucks and trailers bringing and taking wares are driven manually. This offers a enormous potential for automation for the yards of logistics centers. The availability of this potential is correlated to the autonomous forward and backward motion control for standard transportation vehicles. By an experimental system it has been shown that truck and trailer can be maneuvered autonomously at a high degree of precision. For purposes of safety it is necessary to guarantee that at any instant of time the vehicle is within some predefined area. Therefore, this paper introduces the principle of safe cover segments which are never left by the vehicle in motion and defines rules for the connection of such segments forming a safe corridor. [ABSTRACT FROM PUBLISHER]

A distributed control approach based on multiagent negotiation is presented, wherein stops and buses act as agents that communicate in real-time to achieve dynamic coordination of bus dispatching at various stops. The negotiation between a Bus Agent and a Stop Agent is conducted based on marginal cost calculations. We present optimality conditions for the formulated problem, using a negotiation algorithm, which we derive, to coordinate bus holding at various stops. A comparison between the negotiation algorithm and other simple bus control strategies such as on-schedule and even-headway strategies made through simulations verifies the robustness and efficiency of our negotiation strategy to different transit environments, involving both stationary passenger arrivals as well as a variety of nonstationary passenger arrivals. [ABSTRACT FROM PUBLISHER]

The route computation module is one of the most important functional blocks in a dynamic route guidance system. Although various algorithms exist for finding the shortest path, their performance tends to deteriorate as the network size increases. We present an efficient hierarchical routing algorithm that finds a near-optimal route and evaluate it on a large city road network. Solutions provided by the hierarchical routing algorithm are compared with the optimal solutions to analyze and quantify the loss of accuracy. We propose a novel yet simple heuristic to substantially improve the performance of the hierarchical routing algorithm with acceptable loss of accuracy. A network pruning technique has been incorporated into the algorithm to reduce the search space and the correctness of the results is evaluated. The improved hierarchical routing algorithm that incorporates the heuristic techniques has been found to be over 50 times faster than a typical shortest path algorithm. [ABSTRACT FROM PUBLISHER]

The wide variety of remote sensors used in Intelligent Transportation Systems (ITS) applications (loops, probe vehicles, radar, cameras, etc.) has created a need for general methods by which data can be shared among agencies and users who own disparate computer systems. In this paper, we present a methodology that demonstrates that it is possible to create, encode, and decode a self-describing data stream using: 1) existing data description language standards; 2) parsers to enforce language compliance; 3) a simple content language that flows out of the data description language; and 4) architecture neutral encoders and decoders based on ASN.1. [ABSTRACT FROM PUBLISHER]

• Developed a set of concise mathematical models for coherent front propagation and mineral trapping in CCS. • Advanced the model from 1D to 2D coherent state and improved the conceptual understanding. • Established the reaction- or transport-limiting criteria for mineral trapping rate. • Explored the evolution of the coherent front of dawsonite and the impact of hydrodynamic dispersion on the front propagation. After nearly 30 years of research on geological carbon storage, studies providing an in-depth conceptual understanding of mineral trapping processes are still scarce. Based on the reaction front propagation theory, this paper developed a set of concise mathematical models for front propagation and mineral trapping in quasi-2D-advection-diffusion-dispersion-reaction-kinetics systems in the coherent state and explored the nature of long-term mineral trapping processes and the effects of hydrodynamic dispersion on the front propagation. A criterion based on dawsonite volume fraction and front propagation distance was established to determine whether the mineral trapping rate is reaction- or transport-controlled for the coherent reaction fronts. Combined with the numerical simulation, the mantle-magmatic-sourced CO 2 invasion, and long-term CO 2 storage was investigated for the Hailar natural CO 2 reservoir. The conclusions include: (1) The relative errors of the concise models for coherent front propagation speed and mineral trapping rate are 3-10% and 0.5-10%, respectively. (2) For the complete reaction stage, mineral trapping rates are always transport-controlled and are proportional to Darcy velocity, the difference of total dissolved carbon concentrations, and the correction coefficient for the hydrodynamic dispersion; when reaction controlling, the mineral trapping rate is proportional to front propagation distance and upstream dawsonite precipitation rate. (3) Specific results related to propagation speed, front width, hydrodynamic dispersion and mineral trapping rate caused by changing the rate constants of minerals and albite volume fraction were also obtained. [ABSTRACT FROM AUTHOR]

Nanoscale coatings are attractive for managing the biological/material interface as well as for transport control in medical device applications. Construction of biologically derived and mimicking polyelectrolyte multilayers (BioPEMs) and their chemically crosslinked derivatives was evaluated at the nanometer scale and the glucose mass transfer properties were characterized in a physiological environment. Glucose diffusivity through all the BioPEMs was found to be three to four orders of magnitude lower than that of bare substrate. In contrast, permeation rates (dC/dt) were significantly higher than when compared to films comprising the same number of bilayers of synthetic materials—poly(acrylic acid)/poly(allylamine hydrochloride). Crosslinked BioPEMs exhibited decreased diffusivity of glucose up to 51% compared to native BioPEMs. These findings provide fundamental insight into the transport properties of BioPEM coatings that may be useful in maximizing biomimetic properties while also controlling permeation of small molecules in applications such as sensors, filtration, and drug delivery systems. [ABSTRACT FROM AUTHOR]

Secure Flow is a holistic, integrated methodology that addresses all security vectors (paths that a terrorist may take to enter a threat object into the transportation system), allowing people, baggage, and cargo to move via various transportation systems in a secure fashion, while maintaining an "ease of access" to these diverse systems through innovative technology, procedures, and training. Secure Flow is a totally integrated transportation security system. It is a strategic program with multiple integration projects each being a vector such as: checked baggage, checkpoint, cargo/mail, airport, aircraft, port terminal, and cruise ships. Secure Flow identifies requirements for the establishment of protocols, standards, communications, and development of technologies to link deployable security equipment into a totally integrated transportation security system. The objective of Secure Flow is to secure the flow of passengers, baggage, and cargo from origin to destination to meet the operationally viable needs of the future seamless US Transportation System for the traveling public. [ABSTRACT FROM PUBLISHER]

Illumination may increase corrosion rates of important engineering metals. In addition to the well-known photoelectrochemical mechanism which increases dissolution via generation of electron-hole pairs, induced convection via local heating can contribute to increased dissolution. Here, corrosion potential shifts of iron in HCl, aqueous NaCl and NaOH upon illumination with O (1 0 2 W cm−2) white light have been found to be O (10 mV), accompanied by increased corrosion rates. The increase in corrosion potential can be suppressed by stirring. These results are interpreted in the framework of the mixed potential theory. An increase in the diffusion limited current of the O 2 reduction by increased O 2 transport to the surface via induced convection leads to increased corrosion potentials, and thus increased corrosion rates. The induced convection mechanism of increased photocorrosion can be recognised by a delayed onset of corrosion potential shifts. In practice, this mechanism is anticipated to be important mainly in thin film electrolytes under strong illumination. Unlabelled Image • Illumination of a metal leads to heating of the metal surface. • The resulting temperature gradient increases the natural convection velocity. • Increased natural convection increases oxygen transport to the surface. • Increased oxygen transport leads to increased corrosion rates. • Stirring or enforcing convection suppresses the effect. [ABSTRACT FROM AUTHOR]

Materials corrosion is a natural and ubiquitous interfacial process, but is essential to numerous industrial processes. Progress in industrial and material innovations is also marked by developments in search of new solutions to design materials with better anticorrosion activity and longer service lifetime. In particular, recent blossoming in biomimetics has provided remarkable inspirations to design new artificial, passive anticorrosion coatings which are environmentally benign and functional versatile. In this review, the authors first formulate three key design components that underlie the construction of an ideal protective coating, that is, the functional barrier at the coating surface, the transport control of corrosive substances inside the coating, as well as interfacial bonding between the passive coating and the substrate. Then, the authors take a parallel approach to elaborate inspirations from nature and review recent progress in mimicking nature. At last, the authors offer perspectives on the design and development of novel engineered, high‐performance anticorrosion coatings. [ABSTRACT FROM AUTHOR]