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The increasing climate-change-induced tropical cyclone phenomena expose the power grid to significant operation risks by disrupting the normal operation of grid components. This paper considers the failure mechanism with respect to critical grid components and reveals a novel spatiotemporal revolution of grid failures during the passage of typhoons. Based on the spatiotemporal evolution of grid failures, a threshold-based emergency scenario set and the corresponding two-stage robust optimization-based emergency dispatch model are developed. The robust emergency dispatch strategy is obtained using a column-and-constraint generation (C&CG) algorithm. The simulation results show that the proposed robust emergency dispatch strategy can guarantee a considerable degree of robustness under multiple emergency scenarios driven by uncertain typhoon conditions. [ABSTRACT FROM AUTHOR]

Purpose: Virtual reality (VR) has been explored as a training and testing environment in a range of work contexts, and increasingly so in transport. There is, however, a lack of research exploring the role of VR in the training of tram drivers, and in providing an environment in which advances in tram technology can be tested safely. This study aimed to test a novel haptic tram master controller within a tram-based Virtual environment (VE). Design/methodology/approach: The master controller is the primary mechanism for operating a tram, and its effective manipulation can significantly influence the comfort and well-being of passengers, as well as the overall safety of the tram system. Here, the authors tested a haptically enhanced master controller that provides additional sensory information with 16 tram drivers. The feasibility and user acceptance of the novel technology were determined through surveys. Findings: The results indicate that the haptic master controller is seen as beneficial to the drivers suggesting that it could enhance their driving and demonstrate good acceptance. The VE has provided a potential training environment that was accepted by the drivers and did not cause adverse effects (e.g. sickness). Research limitations/implications: Although this study involved actual tram drivers from a local tram company, the authors acknowledge that the sample size was small, and additional research is needed to broaden perspectives and gather more user feedback. Furthermore, while this study focused on subjective feedback to gauge user acceptance of the new haptic technology, the authors agree that future evaluations should incorporate additional objective measures. Practical implications: The insights gained from this VE-based research can contribute to future training scenarios and inform the development of technology used in real-world tram operations. Originality/value: Through this investigation, the authors showed the broader possibilities of haptics in enhancing the functionality and user experience of various technological devices, while also contributing to the advancement of tram systems for safer and more efficient urban mobility. [ABSTRACT FROM AUTHOR]

With the rapid expansion of urban populations and the accelerated pace of urbanization, the concept of urban air mobility (UAM) has emerged. During flights, UAM aircraft need to transmit real-time sensing information to base stations for further processing and analysis. Large-scale real-time data require leveraging the computing capabilities of edge servers at the network edge to reduce transmission delay and energy consumption of UAM aircraft. In cases where edge servers are unable to process information, an unmanned aerial vehicle (UAV) equipped with computing capabilities and operating in low-altitude airspace can serve as a relay to assist in communication and computation. Due to the limited payloads and flight times of UAVs and UAM aircraft, delay and energy consumption within the system pose significant challenges. To tackle these challenges, two fundamental objectives have been proposed: minimizing delay and minimizing energy consumption. Furthermore, an optimization problem has been proposed to minimize the weighted sum of delay and energy consumption. Then, a UAM federated twin delayed deep deterministic policy gradient (UF-TD3) algorithm has been proposed to solve the original problems characterized by complex, non-convex, and inseparable variables. Simulation results show that the proposed UF-TD3 algorithm converges quickly and significantly outperforms four other baseline algorithms in optimizing delay and energy consumption performance. Moreover, compared to the conventional delay minimization strategy and energy minimization strategy, the proposed strategy of minimizing the weighted sum of delay and energy consumption can reduce the delay by 63.8% and reduce energy by 73.96%.

Emergency scenario recognition has diverse applications, including monitoring older adults living alone and detecting crimes. Predominantly, emergency scenario recognition methods rely on cameras, presenting privacy issues, especially in bathrooms and homes. Additionally, most studies concentrate on recognizing simple isolated activity such as falling down and lying down. However, real-life emergency scenarios often more than just isolated activity. This paper introduces a method for classifying emergency scenarios, including falling down, lying down, as well as the combined activities such as falling down and standing up, lying down and standing up, falling down and crawling, and lying down and crawling. Falling and lying down are similar scenarios, and we consider that the people may stand up or crawl afterward. Our approach hinges on the micro-Doppler features derived from continuous-wave radar signals. We first process the human-generated radar echo signals to produce micro-Doppler spectrogram images. Subsequently, we propose an AI model utilizing multi-head attention mechanisms for image training and testing, demonstrating strong performance on our small datasets while reducing computational complexity compared to precious vision transformer models. Preliminary results highlight the efficacy of our approach, with an average recognition accuracy exceeding 95%.

The increasing climate-change-induced tropical cyclone phenomena expose the power grid to significant operation risks by disrupting the normal operation of grid components. This paper considers the failure mechanism with respect to critical grid components and reveals a novel spatiotemporal revolution of grid failures during the passage of typhoons. Based on the spatiotemporal evolution of grid failures, a threshold-based emergency scenario set and the corresponding two-stage robust optimization-based emergency dispatch model are developed. The robust emergency dispatch strategy is obtained using a column-and-constraint generation (C&CG) algorithm. The simulation results show that the proposed robust emergency dispatch strategy can guarantee a considerable degree of robustness under multiple emergency scenarios driven by uncertain typhoon conditions.

Future generations of wireless networks are expected to heavily rely on unmanned aerial vehicles (UAVs). UAV networks have extraordinary features like high mobility, frequent topology change, tolerance to link failure, and extending the coverage area by adding external UAVs. UAV network provides several advantages for civilian, commercial, search and rescue applications. A realistic mobility model must be used to assess the dependability and effectiveness of UAV protocols and algorithms. In this research paper, the performance of the Gauss Markov (GM) and Random Waypoint (RWP) mobility models in multi-UAV networks for a search and rescue scenario is analyzed and evaluated. Additionally, the two mobility models GM and RWP are described in depth, together with the movement patterns they are related with. Furthermore, two-simulation scenarios conduct with help of an NS-3 simulator. The first scenario investigates the effect of UAV Speed by varying it from 10 to 50 m/s. the second scenario investigates the effect of the size of the transmitting packet by varying it from 64 to 1024 bytes. The performance of GM and RWP was compared based on packet delivery ratio (PDR), goodput, and latency metrics. Results indicate that the GM model provides the highest PDR and lowest latency in such high mobility environments. [ABSTRACT FROM AUTHOR]

The assessment of lifeboat coxswain performance in operational scenarios representing offshore emergencies has been prohibitive due to risk. For this reason, human performance in plausible emergencies is difficult to predict due to the limited data that is available. The advent of lifeboat simulation provides a means to practice in weather conditions representative of an offshore emergency. In this paper, we present a methodology to create probabilistic models to study this new problem space using Bayesian Networks (BNs) to formulate a model of competence. We combine expert input and simulator data to create a BN model of the competence of slow-speed maneuvering (SSM). We demonstrate how the model is improved using data collected in an experiment designed to measure performance of coxswains in an emergency scenario. We illustrate how this model can be used to predict performance and diagnose background information about the student. The methodology demonstrates the use of simulation and probabilistic methods to increase domain awareness where limited data is available. We discuss how the methodology can be applied to improve predictions and adapt training using machine learning.

Unconventional emergencies can lead to unforeseen disastrous penalties. Due to their unrepeatable, complex, and unpredictable nature, it is generally hard to establish high-quality Emergency Response Plans (ERPs) for unconventional emergencies, thus posing great challenges for unconventional emergency response. This work proposes a rapid ERP generation approach for unconventional emergencies so as to provide support for emergency decision-making. The generation of ERPs is achieved by exploitation of existing ERPs that contain much emergency response experience. First, a number of ERPs are collected and structurally organized to construct an ERP repository. Then, the applicability of each ERP segment in the repository to a given unconventional emergency is evaluated by a proposed ERP similarity measure and emergency scenario matching mechanism, in which the semantic relevance and the scenario consistency of an ERP segment are taken into account, respectively. Applicable ERP segments are obtained for each section of ERPs, and combined to form a new ERP with the guidance of pre-defined ERP structure. Furthermore, we design an ERP assessment method and perform a case study on the proposed approach which presents encouraging experimental results.

The handling of left ventricular assist devices (LVADs) can be challenging for patients and requires appropriate training. The devices' usability impacts patients' safety and quality of life. In this study, an eye tracking supported human factors testing was performed to reveal problems during use and test the trainings' effectiveness. In total 32 HeartWare HVAD patients (including 6 pre-VAD patients) and 3 technical experts as control group performed a battery change (BC) and a controller change (CC) as an everyday and emergency scenario on a training device. By tracking the patients' gaze point, task duration and pump-off time were evaluated. Patients with LVAD support ≥1 year showed significantly shorter BC task duration than patients with LVAD support <1 year (p = 0.008). In contrast their CC task duration (p = 0.002) and pump-off times (median = 12.35 s) were higher than for LVAD support patients <1 year (median = 5.3 s) with p = 0.001. The shorter BC task duration for patients with LVAD support ≥1 year indicate that with time patients establish routines and gain confidence using their device. The opposite effect was found for CC task duration and pump-off times. This implies the need for intermittent re-training of less frequent tasks to increase patients' safety. [ABSTRACT FROM AUTHOR]

Shipmasters may have to perform unberthing without tugboat assistance when a tsunami warning is issued. Keeping this in mind, we studied emergency unberthing without tug assistance by conducting numerical simulations and full-mission ship maneuvering simulator (SMS) experiments. A panamax class medium-sized bulker and a pure car carrier (PCC) were used as test ships. In the experiments, we established the limitations of basic shiphandling techniques such as stern kick out, backing, and accelerating turn in windy conditions using a mathematical modeling group (MMG)-type mathematical maneuvering model. On the basis of the results, we produced a shiphandling scenario and evaluated it using SMS experiments. We concluded that unberthing without tug assistance in 5 m/s onshore winds is possible. Furthermore, the use of thrusters can greatly reduce the time required for unberthing.

Marine abandonment immersion suits are a vital piece of safety equipment intended to protect individuals from exposure to harsh environmental elements. The operational effectiveness of a well maintained and fitted suit depends on the ability of a user to correctly don a suit system. Thirty-two participants performed immersion suit donning trials in six experimental conditions. Dynamic, pre-abandonment marine emergency scenarios were simulated using a six degrees of freedom motion platform and varying environmental lighting levels. This article details user-suit interaction challenges encountered throughout immersion suit donning tasks and examines their connection to safety and survival in marine emergencies. Analysis of user-suit functionality during the donning process is critical for identifying current deficiencies in order to develop future design solutions, training methodologies and ultimately improve users’ practical competencies.

The paper presents threat assessment of potential terrorist attacks to the transport infrastructure. The range of transportation infrastructure has spread and includes railway, inland waterways, road, maritime, air, intermodal transport infrastructure and intelligent transport systems (ITS). ITS service is the provision of an ITS application through a well-defined organisational and operational framework with the aim of contributing to the user safety, efficiency, comfort and/or to facilitate or support transport and travel operations. Terrorism means acts of violence committed by groups that view themselves as victimized by some notable historical wrong. Although these groups have no formal connection with governments, they usually have the financial and moral backing of sympathetic governments. Typically, they stage unexpected attacks on civilian targets, including transport infrastructure, with the aim of sowing fear and confusion. Based on the analyses, transportation infrastructure is potentially threatened with terrorism attacks, especially road and rail infrastructure (about 23 %), and to a smaller degree the maritime and air transport infrastructure (about 2 %). There were 90,3% of incidents involve land transport (74,5% – vehicles, 9,5% – buses, 6,3% - rail) covered the 41-year period 1967-2007 in the USA. Legal steps to fight terrorism have been taken on the international level, furthermore, some institutions have been established for this purpose.

The paper evaluates effectiveness of fire drills for emergency and responding to PSC inspections on board. A brief background about the PSC inspection on fire drills on board is introduced in the beginning. Then the significance of effectiveness evaluation on fire drills is presented. Next, legal ground is discussed on International Conventions, including regulation of related regional group, national maritime laws and rules and Concentrated Inspection Campaign (CIC). Furthermore, PSC New Inspection Regime (NIR) for Paris MOU and Tokyo MOU are also discussed, and many deficiencies related to fire safety measures found in the PSC inspection are statistically analyzed. More importantly, the paper introduces System Engineering Theory, presents the principle and method of effectiveness evaluation, focuses on the preparation, performance and rehabilitation of fire drill and develops the Criterion of Effectiveness Evaluation. Finally, some suggestions are raised to carry out effectiveness evaluation for emergency and responding to the PSC inspection.

Accident scenarios are the foundations of emergency responses. Hybrid Petri net is used to model emergency scenarios and responses comprehensively and systematically. Here, both the discrete events of scenarios and their evolution are characterized clearly. Elements of accident scenarios are expressed normatively using a knowledge element model and hierarchical theory, providing standardized descriptions of the different scenario stages. Then, a case study of an oil pipeline leak is examined to verify the logic of the hybrid Petri net and the expressions of attributes using the knowledge element model. The results show objective realizations of the scenario and the evolution of emergent events, enabling a formalized expression of emergency knowledge that can be used to establish an emergency knowledge base. [ABSTRACT FROM AUTHOR]

To manage an emergency situation in an effective way it is necessary to have certain capabilities. These capabilities focus on preventing, mitigation, responding to, and recovering from the major events. Designing a system of emergency exercises without a balanced approach for all capabilities may fail the preparedness. The main objective of this study is finding the main concentration of the practiced exercises on the desired capabilities. The Content Analysis technique was used to conduct a thematic analysis of the contents of records of some implemented scenarios. The findings showed that there was not a balanced system for enhancing the needed capabilities. Most of the planning attempts concentrated on the response phase and aspects like the protection and recovery capabilities were ignored. To plan an exhaustive system of emergency preparedness such findings are helpful. [ABSTRACT FROM AUTHOR]

This paper presents an innovative proposal for the selection of electrical loads in intelligent networks when main power sources are limited or totally absent (in the following: in emergency conditions). The control strategy is based on the mathematical approach of the basis 0–1 Knapsack Problem. Results from three different algorithms are compared: Tabu Search, Greedy heuristic and dynamic programming. To verify correctness and accuracy in the solutions, a MatLab software have been developed. To evaluate the achieved results, a case study is shown in a true-life environment. [ABSTRACT FROM AUTHOR]

The issue of environmental risk assessment currently deserves great attention. In order to protect the environment, maintain healthy living conditions, and prevent environmental damage, the member states of the European Union have adopted a Directive of the European Parliament and of the Council on environmental liability with regard to the prevention and remedying of environmental damage. The directive classifies two types of operators with different liability regimes for environmental damage, namely, the regime with no-fault (strict) liability and liability for fault. With the adoption of the directive, among experts, operators and the general public have posed questions about how to assess the risk of environmental damage. At present, there is still no uniform procedure for assessing environmental risks, which would create a comprehensive methodological framework for assessment for this type of risk. Due to the non-existent risk assessment methodology for operators with strict liability regimes and the lack of a systematic search for risk sources, a risk assessment procedure is proposed that provides guidance in a sequence of several steps on how to implement the obligations arising from the adopted Environmental Liability Directive. The proposed procedure was verified on a specific operator with a strict liability regime. The environmental risk analysis performed through the proposed procedure provided information on possible operational problems and verified its applicability. Last but not least, the use of the proposed procedure makes it possible to identify serious sources of risk and to establish necessary preventive measures to prevent the occurrence of environmental damage. [ABSTRACT FROM AUTHOR]

The present work aims at developing a hydraulic simulation model for the aqueducts of Thessaloniki city in Greece to model the current operating state of the network, as well as its response to emergency conditions resulting from failure in one of them. Hydraulic simulations performed using WaterGEMS software in an extended period simulation (EPS) mode entail estimating water demand in all areas of the conurbation and calibrating the model under both normal and abnormal conditions. Calibration parameters set include the pipes' roughness coefficients and head loss characteristics of throttle control valves (TCVs). Failure in the city's aqueducts is confronted with the development and hydraulic simulation of five emergency scenarios of network operation, two of which consider possible interconnections of the studied aqueducts. These scenarios, which include appropriately defined intermittent water supply schedules for the aqueducts, are created on the basis of fair and equitable management of water among the different areas of the city, also assuming a small number of interventions/operations during the crisis. The simulations performed reveal quite a satisfactory compliance of the system's operation with the defined schedules, and an improved management of limited water reserves in some areas of the network when considering interconnections of the city's aqueducts. [ABSTRACT FROM AUTHOR]

Background: Emergency response skills are essential when events such as seizure, anaphylaxis, or hemorrhage occur in the outpatient setting. As services and procedures increasingly move outside the hospital, training to manage complications may improve outcomes., Objective: The objective of this study was to evaluate a simulation-based curriculum in outpatient emergency management skills with the outcome measures of graded objective performance and learner self-efficacy., Study Design: This pre- and postcurriculum study enrolled residents and fellows in Obstetrics and Gynecology and Family Medicine in a simulation-based, outpatient emergency management curriculum. Learners completed self-efficacy questionnaires and were videotaped managing 3 medical emergency scenarios (seizure, over-sedation/cardiopulmonary arrest, and hemorrhage) in the simulation laboratory both before and after completion of the curriculum. Evaluators who were blinded to training level scored the simulation performance videotapes using a graded rubric with critical action checklists. Scenario scores were assigned in 5 domains and globally. Paired t-tests were used to determine differences pre- and postcurriculum., Results: Thirty residents completed the curriculum and pre- and postcurriculum testing. Subjects' objective performance scores improved in all 5 domains (P<.05) in all scenarios. When scores were stratified by level of training, all participants demonstrated global improvement. When scores were stratified by previous outpatient simulation experience, subjects with previous experience improved in all but management of excess sedation. Pre- and postcurriculum self-efficacy evaluations demonstrated improvement in all 7 measured areas: confidence, use of appropriate resources, communication skills, complex airway management, bag mask ventilation, resuscitation, and hemorrhage management. Self-efficacy assessment showed improvement in confidence managing outpatient emergencies (P=.001) and ability to communicate well in emergency situations (P<.001)., Conclusion: A simulation-based curriculum improved both self-efficacy and objectively rated performance scores in management of outpatient medical emergencies. Simulation-based curricula should be incorporated into residency education., (Copyright © 2017 Elsevier Inc. All rights reserved.)