Casualty Risk Research Articles

Terrorist Attacks against Sports Venues: Emerging Trends and Characteristics Spanning 50 Years.

Sports venues foster community and support local economies. Due to their capacity to host hundreds to thousands of spectators, sports venues are vulnerable to becoming targets of terrorism. Types of venues targeted, regional trends, and methods of attack employed world-wide have not been well-described. A search of the Global Terrorism Database (GTD) was conducted from 1970 through the end of 2019. Pre-coded variables for target type "business" and target subtype "entertainment/cultural/stadium/casino" were used to identify attacks involving venues where sports events might be viewed by spectators as part of an audience. Sports venues were specifically identified using the search terms "sport," "stadium," "arena," and "ring," as well as mention of any specific sport. Two authors then manually reviewed each entry for specific information to confirm appropriateness for inclusion, selecting preferentially for attacks against venues where watching a sports event was the primary focus for the majority of the attendees. Descriptive statistics were performed using R (3.6.1). Seventy-four (74) terrorist attacks targeting sports venues were identified from January 1, 1970 through December 31, 2019. Thirty-three (33) attacks, or 44.6% of attacks, involved soccer stadiums or soccer venues, while 33.8% of attacks (25 attacks) involved unspecified sports venues. A bombing or explosion was the most frequent method of attack employed, comprising 87.8% of attacks. The highest number of attacks occurred in the Middle East & North Africa. In total, 213 persons died and 699 more were wounded in attacks against sports venues. Although terrorist attacks against sports venues are uncommon, they carry the risk of mass casualties, especially when explosives are used. A greater understanding of the threat posed by terrorist attacks against sports venues can aid emergency preparedness planning and future medical responses.

Development of Autonomous Driving Patrol Robot for Improving Underground Mine Safety

To improve the working conditions in underground mines and eliminate the risk of human casualties, patrol robots that can operate autonomously are necessary. This study developed an autonomous patrol robot for underground mines and conducted field experiments at underground mine sites. The driving robot estimated its own location and autonomously operated via encoders, IMUs, and LiDAR sensors; it measured hazards using gas sensors, dust particle sensors, and thermal imaging cameras. The developed autonomous driving robot can perform waypoint-based path planning. It can also automatically return to the starting point after driving along waypoints sequentially. In addition, the robot acquires the dust and gas concentration levels along with thermal images and then combines them with location data to create an environmental map. The results of the field experiment conducted in an underground limestone mine in Korea are as follows. The O2 concentration was maintained at a constant level of 15.7%; toxic gases such as H2S, CO, and LEL were not detected; and thermal imaging data showed that humans could be detected. The maximum dust concentration in the experimental area was measured to be about 0.01 mg/m3, and the dust concentration was highly distributed in the 25–35 m section on the environmental map. This study is expected to improve the safety of work by exploring areas that are dangerous for humans to access using autonomous patrol robots and to improve productivity by automating exploration tasks.

Public health crisis and risky road behaviors.

This study investigates how exposure to riskier environments influences risky road behaviors, using the COVID-19 pandemic as a natural experiment. Utilizing administrative individual traffic violation records from Taipei, where neither mandatory lockdown nor mobility restrictions were imposed, we find that pandemic-induced risk decreased speeding violations and that the effect was transitory. However, no significant changes were observed concerning violations with a minimal risk of casualties, such as illegal parking. These findings suggest that experiencing a higher level of life-threatening risk discourages risky behaviors concerning human life but has little spillover effect on those concerning only financial costs.

Electric Vehicle Lithium-ion Battery Ageing Analysis under Dynamic Condition: A Machine Learning Approach

Currently, the smart cities, smart vehicles, and smart gadgets will improve the way of living standard. Cloud connectivity of IoT sensed devices will capture real-time data in the cloud which helps to improve the system performance and quick response to queries. Electric Vehicle battery health diagnosis plays an important role in the proper functioning of the battery management system, guarantees safety, and warranty claim. Society 5.0 develops with the advancement in the road, infrastructure, better connectivity, transportation, and options available to purchase. Battery health cannot be measured directly. There are internal and external factors that affect battery health such as State of Charge, model parameters, charging/discharging method, temperature, Depth of Discharge, C-rate, battery chemistry, form factor, thermal management, and load change effect. Battery degrades due to both calendar ageing and cyclic ageing. Artificial Intelligence plays a significant role in Battery management system due to the nonlinear behavior of lithium-ion battery. Prediction of battery health accurately and in due time will reduce the risk of recklessness. Timely maintenance will reduce the risk of fatal accidents. This paper presents different batteries analysis under different discharge voltage and capacity conditions. Different machine learning algorithms such as Neural Network, Modified Support Vector Machine (M-SVM) and Linear Regression are used to predict state of health. The proposed M-SVM performs well with less error for all four-battery discharge data.

Evaluation of Casualty Risk Index for Evacuating When Inundation Occurs on Excavation Construction Sites

Recently, inundation accidents occur repeatedly on underground excavation construction sites owing to frequent intensive rainfall events. In the case of the inundation of underground construction sites, injury and drowning accidents may occur on the evacuation route. However, no method or standard for calculating the risk of casualty while evacuating workers has been proposed. In this study, we defined the casualty risk index (CRI) and developed a method for estimating CRI. We adopted the “HV,” which is the product of height (water depth) and velocity (water velocity) recommended by previous researches. The “HV” indicates that humans can walk safely in water flow without stumbling. The proposed method was applied to a hypothetical underground construction site in the city of Yeosoo. ArcGIS Pro was used to model the hypothetical excavation site, and XPSWMM was used to simulate rainfall runoff and two-dimensional hydraulic simulation. While the runoff was flowing into an underground construction site, we simulated the water height and water velocity on the evacuation route to estimate the CRI. The results showed that CRIs from various rainfall scenarios remained in the safe criteria, indicating that workers could safely evacuate from the site in the rainfall scenarios. However, the CRI is influenced by site-based factors, and these factors are discussed.

THE RELATIONSHIP BETWEEN SELF EFFICACY AND EARTHQUAKE AND TSUNAMI DISASTER PREPAREDNESS AMONG STUDENTS OF SMAN 13 BANDA ACEH

Disaster is often perceived as uncontrollable things. Self-efficacy has been identified in having significant influence toward behavior in facing uncontrollable problems. School is one of the areas that have a higher risk of casualties during earthquake and tsunami because it is a gathering place of students, teachers, and other academic members especially on school hours; Therefore, they need the preparedness to face the disaster. The purpose of this research is to understand the correlation between self-efficacy and disaster preparedness of earthquake and tsunami on students at State Senior High School 13 of Banda Aceh. The type of the research is descriptive-correlative method with a cross-sectional study design. The sampling technique used is total sampling. The instrument used is a questionnaire which is self-efficacy questionnaire and preparedness questionnaire that develop by LIPI-UNESCO/ISDR. The data analysis used in this research was Spearman’s Correlation. This research shows that there is a significant correlation between self-efficacy and disaster preparedness on students at State Senior High School 13 of Banda Aceh. The data analysis shows that p-value of self-efficacy (0.001) including dimension of level (0.007), dimension of strength (0.002), dimension of generalization (0.001). Schools are recommended to improve students’ self-efficacy with disaster preparedness simulation training of earthquake and tsunami.

Щодо питання оцінки залишкового ресурсу трубопроводів

Prediction of the pipeline system residual life can be a valuable tool for engineers and operators in developing future strategies for safe application, including planning technical assessment and inspections, as well as the formation of an effective maintenance schedule. This will minimize the risks of pipeline system failures until the expected end of its service life. However, given the large number of factors affecting the formation of defects of different nature, achieving accurate predictions becomes a challenging task. A detailed assessment and prediction of the main defect indicators in pipeline systems can help to prevent leaks and ruptures at the facility, reducing the risks of accidents and human casualties. This also significantly reduces operational risks, which helps to avoid material losses, including expenses that may be caused by large-scale pipeline replacement. This article examines the main approaches described in the commonly used regulatory standards that allow estimating the service life, suitability for use, and residual life of pipelines. In the course of the work, the following techniques have been studied: inspection, facility testing and monitoring, processing and evaluation of the obtained data on defects, calculation of technical parameters for assessing the suitability of components for their further usage, as well as other engineering recommendations for analyzing the facility at some stages of its lifecycle. Based on the work done, it has been found that the complex use of several relatively different or, conversely, compatible regulatory documents, equipment, and software (considering the specific needs and specifications of the project) is a fairly popular practice that allows you to improve the evaluation process of the residual life and provides more reliable results when assessing the technical condition of the facility.

Seismic fatality risk evaluation framework for existing buildings in Switzerland

The Swiss code SIA 269/8 for the seismic evaluation of existing structures is risk-based. It relies on the compliance factor αeff, defined as the ratio of the seismic capacity of an existing structure to the required seismic capacity of a hypothetical identical new structure, to indirectly evaluate the casualty risk posed by the existing structure. While it is convenient to have a direct relationship between the casualty risk and the degree of code compliance of the existing structure, it is debatable if the contributions of the seismic hazard, structural performance and occupancy to the casualty risk should be merged into a single quantity, conflicting with the multi-component nature of seismic risk. This paper presents a graphical framework to evaluate the seismic fatality risk for existing buildings. The framework is based on the PEER Center performance-based earthquake engineering methodology to provide a transparent view of the contributions of different sources of hazard and risk. Starting from a seismic hazard model, probabilistic seismic demand, damage and loss models are introduced, taking the uncertainty into account at each step. The final product of the proposed framework, a loss curve representing the (annual) exceedance rate of fatality counts, enables engineers and building owners to make better, risk-based decisions. The proposed framework is demonstrated for an existing building in Switzerland. Notably, in addition to the SIA 269/8 evaluation method, this demonstration compares eight hybrid approaches differentiated by the utilized structural assessment techniques (nonlinear static pushover vs. incremental dynamic analysis), uncertainty propagation in the demand model (record variability only vs. record variability and epistemic uncertainty) and solution strategies (closed-form vs. numerical) to find a practical compromise between the accuracy and the computational effort. A comparison of the obtained results shows that the SIA 269/8 evaluation method underestimates the fatality risk for the presented building and identifies a practical alternative based on the proposed graphical framework.

Evaluation of the effectiveness of anomalous systems in gas subsidiaries (Case study of Alborz Gas Company)

An anomaly is an unsafe condition or action that has the potential to cause an accident. These conditions or unsafe practices in gas companies play a very important role in the occurrence of gas leaks and fires. Any unsafe acts can lead to unpleasant incidents for citizens and their homes and property. The aim of this study is to increase the effectiveness of anomalous systems in gas subsidiaries of Alborz province. To conduct this study, Tripod Beta technique to draw a diagram of analysis of gas accidents in homes in Alborz province and hierarchical analysis method was used to assess the risk of injuries, casualties and unintentional house fires. In the first stage, information on gas leaks and fires was collected by reviewing the documents related to the winter events of 2020. Then the sum of the mentioned conditions was studied as a hypothetical model. In the second step, the mentioned model was analyzed using Tripod Beta method and the causes of the accident were determined by the capability of the study method. The obstacles studied were technical safety regulations and the creation of a safe environment. The immediate reason attached to the technical safety regulations was the lack of proper understanding of the valve opening and closing sign. Another immediate reason for creating a safe environment was the lack of safe equipment. The precondition for not understanding the open and closed sign of the valve, lack of sufficient knowledge and the precondition for not using safe equipment, buying unsafe equipment and the hidden reason for lack of sufficient knowledge, lack of training and the hidden reason for buying unsafe equipment was poor economic situation. The results of this study indicated that fire-related conditions are of the utmost importance in assessing the risk of unintentional house fires. Failure to pay attention to safety points while using gas-related equipment, poor condition of the building and more male residents have the most anomalies in causing gas company accidents.

Numerical Investigation on Fire Performance of LSF and Steel Modular Floor Panels

The steel Modular Building Systems (MBSs) that have been influenced by the Light-gauge Steel Frame (LSF) techniques have become a prominent culture in the industry. However, the detrimental behaviour of steel structural components at high temperatures has elevated the risk of fatal accidents in the event of a fire. Although several research investigations have addressed the fire performance of steel modular wall systems, the behaviour of modular floor systems has not been adequately addressed in the state of the art. Hence, to promote the fire safety and optimum design techniques in the modular construction industry by addressing the aforementioned research gap, this study investigated 48 conventional LSF and MBS floors for their structural and insulation Fire Resistance Levels using Finite Element Modelling (FEM) and Heat Transfer Analyses (HTA) techniques. Initially, full-scale experimental fire tests were modelled using FEM methods, and the validity of the techniques was verified prior to the analyses of parametric floor systems. Furthermore, the structural behaviour of the channel section joists in the elevated temperatures was studied, and hence a correlation was established to determine the critical steel temperature at the structural fire failure with respect to the applied Load Ratio (LR). An additional 12.5 mm thick plasterboard sheathing on single plasterboard sheathed floors resulted a 30 min improvement in structural and insulation FRLs. In addition, the modular floor systems demonstrated enhanced structural and insulation Fire Resistance Levels (FRLs) against the corresponding conventional LSF floor designs due to double LSF skin build-up. The incorporation of rockwool insulation and the increase in the insulation volume implied increased structural and fire performances. However, insulation material in the modular designs was more effective. The fire-rated conventional and modular LSF floor systems are expected to be practised in the construction industry to achieve required fire resistances with optimum material usage.

Risk Control of Mission-Critical Systems: Abort Decision-Makings Integrating Health and Age Conditions

The mission abort is an effective action to reduce the risk of casualties and enhance the survivability of mission-oriented systems, such as aircrafts, submarines, and unmanned aerial vehicles (UAV). A key target of operators in real mission environment is to strive for balance between the success possibility of a mission and system survivability (SS), via elaborate mission abort plans. In this article, we design mission abort policies based on two crucial information: 1) degradation degree of monitored health features, and 2) system age. Accordingly, the operators may abort the mission if the degradation attains a preset control limit at early system ages, or continue the task otherwise. We carry out loss analysis to determine the optimal abort action, by linking MSP and SS. Structural insights regarding the optimality of degradation control limit as well as age threshold are explored. For a comparative purpose, the performances of some heuristic abort policies are analytically evaluated. We make contribution by scheduling mission abort plans harnessing both condition monitoring and age information, which promotes the timeliness and robustness of risk control. A case study on inertial navigation systems of UAV executing line inspection missions is used to illustrate the applicability and superiority of the proposed abort policies.

Raptors at risk: Attributes of mortality within an anthropogenic landscape in the Mid-Hills region of Nepal

Wildlife rescue and rehabilitation centers offer important insights regarding the threats and attributes associated with raptor casualties. We utilized a data set on raptors admitted to a single wildlife rescue center (WRC) in the Mid-Hills region of Nepal by applying two approaches. First, we explored the overview of species admitted and the cause of admission at WRC, and modeled the outcome (survival, mortality) of frequently admitted raptor species (FARS) by analyzing the cause of admittance, the season of admittance, and age category through binary logistic regression. Second, we identified the high-risk zone for raptors through an ensemble approach using multiple species distribution modeling algorithms in BIOMOD2. A total of 17 species of raptors with 830 cases of admittance; Black Kite (Milvus migrans) 47%, Barn Owl (Tyto alba) 24%, Eurasian Eagle-Owl (Bubo bubo) 12%, and other species (17%) were recorded at the WRC over the course of five years (2017–2021). Unknown causes (39%) comprised the largest proportion of admittance, followed by illegal captivity (17%), injured by dogs (10%), and injured by humans (10%). Among the three FARS, the mortality rate was highest in the Barn Owl (62%), followed by the Eurasian Eagle-Owl (55%) and the Black Kite (47%). The model with an additive effect of species, cause, and age category was the best fit model to predict the outcome for FARS. Out of the total study area (705 km2), 19% was under high-risk, 41% was under medium-risk, and 40% was under low-risk. Most of the high-risk zones were incorporated within agricultural areas (57%) and built-up areas (31%). The variation in mortality rate among the FARS indicates that species-specific conservation strategies need to be developed to reduce casualty risk. Identified potential anthropogenic threats and their impact on the survivability and mortality of raptors in this study could help to mitigate casualties. Moreover, the high-risk areas associated with raptor casualties in this study need to be prioritized to implement the conservation endeavors for the raptors.

Interpretable Dynamic Ensemble Selection Approach for the Prediction of Road Traffic Injury Severity: A Case Study of Pakistan’s National Highway N-5

Road traffic accidents are among the top ten major causes of fatalities in the world, taking millions of lives annually. Machine-learning ensemble classifiers have been frequently used for the prediction of traffic injury severity. However, their inability to comprehend complex models due to their “black box” nature may lead to unrealistic traffic safety judgments. First, in this research, we propose three state-of-the-art Dynamic Ensemble Learning (DES) algorithms including Meta-Learning for Dynamic Ensemble Selection (META-DES), K-Nearest Oracle Elimination (KNORAE), and Dynamic Ensemble Selection Performance (DES-P), with Random Forest (RF), Adaptive Boosting (AdaBoost), Classification and Regression Tree (CART), and Binary Logistic Regression (BLR) as the base learners. The DES algorithm automatically chooses the subset of classifiers most likely to perform well for each new test instance to be classified when generating a prediction, making it more efficient and flexible. The META-DES model using RF as the base learner outperforms other models with accuracy (75%), recall (69%), precision (71%), and F1-score (72%). Afterwards, the risk factors are analyzed with SHapley Additive exPlanations (SHAP). The driver’s age, month of the year, day of the week, and vehicle type influence SHAP estimation the most. Young drivers are at a heightened risk of fatal accidents. Weekends and summer months see the most fatal injuries. The proposed novel META-DES-RF algorithm with SHAP for predicting injury severity may be of interest to traffic safety researchers.

Can satellite precipitation estimates capture the magnitude of extreme rainfall Events?

ABSTRACT With the increasing frequency of extreme rainfall events, the likelihood of rainfall disasters is also increasing, presenting serious risks of casualties and economic losses. Therefore, exploring the capability of Satellite-based Precipitation Products (SPPs) to capture the magnitudes of extreme rainfall events is significant for preventing precipitation-related disasters. Selecting ten heavy rainfall events in wet seasons over China, this study evaluated the performance of mainstream SPPs from the Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) and Global Satellite Mapping of Precipitation (GSMaP) in determining the extreme values of heavy rainfall events. The main findings are as follows: (1) SPPs significantly underestimated the magnitudes of extreme rainfalls events, with the most underestimated and closest values for certain events reaching only one-tenth and 50% of ground station values, respectively; (2) the evaluation of the top 1% hourly precipitation presented similar evident errors, with mean relative bias (BIAS) and root mean square error (RMSE) of approximately −80% and 40 mm hour−1; (3) the spatiotemporal patterns of IMERG-Final were closer to those of the ground station and GSMaP-Now captured more maximum values of the ten events. Nevertheless, the accuracy of these SPPs is still not sufficient for the analysis of extreme rain disasters.

Terrorist Attacks Against Performing Arts Venues: Global Trends and Characteristics Spanning 50 Years.

In fostering community and culture through entertainment in shared spaces, performing arts venues have also become targets of terrorism. A greater understanding of these attacks is needed to assess the risk posed to different types of venues, to inform medical disaster preparedness, to anticipate injury patterns, and to reduce preventable deaths. A search of the Global Terrorism Database (GTD) was conducted from the year 1970 through 2019. Using pre-coded variables for target/victim type and target subtype, attacks involving "business" and "entertainment/cultural/stadium/casino" were identified. Attacks targeting performing arts venues were selected using the search terms "theater," "theatre," "auditorium," "center," "hall," "house," "concert," "music," "opera," "cinema," and "movie." Manual review by two authors was performed to confirm appropriateness for inclusion of entries involving venues where the primary focus of the audience was to view a performance. Descriptive statistics were performed using R (version 3.6.1). A total of 312 terrorist attacks targeting performing arts venues were identified from January 1, 1970 through December 31, 2019. Two-hundred nine (67.0%) attacks involved cinemas or movie theaters, 80 (25.6%) involved unspecified theaters, and 23 (7.4%) specifically targeted live music performance venues. Two-hundred thirty-four (75.0%) attacks involved a bombing or explosion, 50 (16.0%) damaged a facility or infrastructure, and 17 (5.4%) included armed assault. Perpetrators used explosives in 234 (75.0%) attacks, incendiary weapons in 50 (16.0%) attacks, and firearms in 19 (6.1%) attacks. In total, attacks claimed the lives of 1,307 and wounded 4,201 persons. Though fewer in number, attacks against music venues were responsible for 29.4% of fatalities and 35.0% of those wounded, and more frequently involved the use of firearms. Among 95 attacks falling within the highest quartile for victims killed or wounded (>two killed and/or >ten wounded), 83 (87.4%) involved explosives, seven (7.4%) involved firearms, and three (3.2%) involved incendiary methods. While uncommon, terrorist attacks against performing arts venues carry the risk for mass casualties, particularly when explosives and firearms are used.

MONITORING LANDSLIDE DISPLACEMENTS THROUGH MAXIMUM CROSS-CORRELATION OF SATELLITE IMAGES

Abstract. Landslides are one of the most dangerous and disastrous geological hazard worldwide, posing threats to human life, infrastructures and to the natural environment. Consequently, monitoring active landslides is crucial in order to reduce the risk of damages and casualties. With this aim, this work proposes a way to compute landslide displacements through time, by exploiting the great availability of high quality multispectral satellite images. The developed procedure produces maps of displacement magnitude and direction by means of local cross-correlation of Earth Observation data from the Sentinel-2 and PlanetScope missions. The Ruinon landslide, an active landslide in Northern Lombardy, Italy, was selected as a case study. The workflow of the developed procedure is described, and the results are presented and discussed. Moreover, a validation of the analysis by comparison with UAV surveys of the landslide is reported, along with a discussion on future developments and improvements of this technique. This work was designed to be entirely based on free and open-source GIS software and to rely mainly on open data. These characteristics allow the proposed analysis to be easily replicated, customized, and empowered.

A numerical approach to evaluate temperature-dependent peridynamics damage model for destructive atmospheric entry of spacecraft

AbstractThe evaluation of the on-ground casualty risk assessments due to a controlled or uncontrolled re-entry is highly sensitive to the accurate prediction of fragmentation events during an atmospheric re-entry. The main objective of this study is an investigation into the use of peridynamics (PD) to improve the analysis of fragmentation during atmospheric re-entry with respect to currently adopted semi-empirical approaches. The high temperatures characterising such scenarios may substantially impact fragmentation, which requires appropriate modelling of the damage process within the PD method. The damage models in PD require experimentally determined fracture mechanical properties that are unavailable as a function of temperature. This work proposes a numerical methodology to estimate the PD damage parameters changes with temperature to enable the study of fragmentation during atmospheric re-entry. Initially, tensile-testing simulation experiments are performed in peridynamics to calibrate material parameters for steel and aluminium alloys as a function of temperature. Then, a parametric study is carried out to evaluate the temperature-dependent damage model parameters for the same materials. The applicability of the proposed methodology is showcased using a re-entry test case scenario.

Efficacy of H2O2 on the removal kinetics of H2S in saltwater aquaculture systems, and the role of O2 and NO3−

The occurrence of hydrogen sulfide (H2S) represents a challenge for recirculating aquaculture systems (RAS) under saline conditions. Even low concentrations of the toxic gas can result in sudden mass mortalities of fish, leading to large economic losses. There is an urgent need for efficient strategies to remove H2S, which can be applied effectively with a short response time, to prevent the risk of H2S-induced casualties. This study examines the kinetics of the two common oxidants applied to rearing water in a RAS facility; oxygen (O2) and hydrogen peroxide (H2O2) and evaluates their efficiency and applicability for the removal of H2S in an industrial RAS. Furthermore, we tested whether nitrate (NO3−) can be an oxygen donor in the chemical oxidation of H2S. The baseline oxidation rates of H2S by O2 were determined in air-equilibrated seawater (SW) and RAS water (RASW). The feasibility of using H2O2 as a practical treatment was evaluated by testing increasing H2O2 to H2S ratios in SW. In addition, RASW dilutions that yielded different concentrations of NO3− and total chemical oxygen demand (TCOD) were tested to identify their effects on H2S removal. The half-lives (t½) of H2S, derived from O2 oxidation rates, were considerably shorter in SW (118.5 ± 28.6 min) compared to RASW (168.0 ± 18.7 min). The addition of a 1:1 mole ratio of H2O2 to H2S, significantly increased the removal rate and decreased the half-life (t½) of H2S in SW to 29.5 ± 6.6 min. Further increasing H2O2:H2S ratios to 2:1 and 4:1, reduced t½ to 21.7 ± 5.2 and 17.4 ± 6.1 min, respectively. Similarly, a dosage of H2O2 at a ratio of 1:1 in RAS water resulted in a considerably shorter t½ of 86.1 ± 10.1 min. The influence of organic matter on the required H2O2 dose was demonstrated by the t½, which were reduced by 49% in RAS water and 75% in SW. NO3− was not found to be involved in the chemical removal of H2S. The results provide an improved understanding of the influence of RAS water chemistry and quality on H2S kinetics and the direct applicability of the kinetics for treating acute H2S levels in RAS to avoid mass mortalities. In conclusion, the addition of H2O2 is an efficient water treatment technology for H2S removal, and by adjusting H2O2 dosages accordingly to the concentrations of H2S and specific systems water parameters, a t½ <30 min can be achieved. Thus the technology is applicable in an industrial RAS, as a treatment process for acute levels of the hazardous gas H2S that is easily implemented, and safe for the fish.

Risky behavior analysis for cross-border drivers: A logit model and qualitative comparative analysis of odds of fault and injury vulnerability in Guangdong, Hong Kong and Macau

Introduction: Due to globalization and the acceleration of cross-border exchanges, cross-border risk behaviors have received widespread attention. Previous research has concluded that foreign cross-border drivers engage in relatively more risk-taking behavior patterns and are likely to experience a higher crash rate or be more inclined to cause severe crashes. However, there is little evidence on the comparison of drivers who belong to the same ethnic group driving across within-country borders. Method: Based on the cross-border motor-vehicle crash reports in 2006–2010 from the Road Traffic Accident Database of the China Ministry of Public Security, this paper examines the risk factors of being at fault and getting killed or seriously injured in cross-border traffic crashes and casual paths toward crash liability and injury severity for Hong Kong and Macao drivers driving in the Chinese mainland. Results: There are extremely complex factors behind drivers from Hong Kong and Macao causing at-fault crashes or sustaining fatal and serious injuries in the Chinese mainland. Factors such as gender, age, illumination, and weather conditions do not individually affect the risk of driver at-fault crashes or severe casualties in the crashes among Hong Kong and Macao drivers driving in the Chinese mainland. Nonetheless, collectively, these factors influence them along with different vehicle types, roads, and environmental factors. Conclusions: This paper provides more theoretical findings for understanding the compound effect of multiple risk factors involving cross-border at-fault crashes or serious casualties. The conclusions of this research are valuable as representative references for cross-border risk management policies. Practical applications: To reduce the effects of different factors on cross-border risky driving behaviors and/or injurious crashes, various measures should be focused on, including specialized driver training, enhancement of the roads/environment, development of effective road safety campaigns, and directives facilitating cross-border cooperation in the field of road safety.

Unnecessary risks created by uncontrolled rocket reentries

Most space launches result in uncontrolled rocket body reentries, creating casualty risks for people on the ground, at sea and in aeroplanes. These risks have long been treated as negligible, but the number of rocket bodies abandoned in orbit is growing, while rocket bodies from past launches continue to reenter the atmosphere due to gas drag. Using publicly available reports of rocket launches and data on abandoned rocket bodies in orbit, we calculate approximate casualty expectations due to rocket body reentries as a function of latitude. The distribution of rocket body launches and reentries leads to the casualty expectation (that is, risk to human life) being disproportionately borne by populations in the Global South, with major launching states exporting risk to the rest of the world. We argue that recent improvements in technology and mission design make most of these uncontrolled reentries unnecessary, but that launching states and companies are reluctant to take on the increased costs involved. Those national governments whose populations are being put at risk should demand that major spacefaring states act, together, to mandate controlled rocket reentries, create meaningful consequences for non-compliance and thus eliminate the risks for everyone.