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Feeding broiler chickens a probiotic biopreparation containing bacteria of the genus Bacillus subtilis and Bacillus licheniformis leads to improved feed digestion, increased productivity, and immune status, as well as reduced insemination by opportunistic and pathogenic microorganisms of slaughter products. It enhances the level of prevention and treatment of various poultry diseases. The purpose of the work is to carry out a microbiological analysis of the slaughter products of broiler chickens after drinking the probiotic biological preparation “Subtiform” in doses of 0.5 g, 2.0, and 4.0 g per 10 dm3 of water. The material (major pectoral muscle and internal organs) was examined by bacteriological methods. It was established that the content of MAFAM in the control and experimental groups 1, 2, and 3 of the chilled slaughter products of broiler chickens for 1, 3, and 5 days of storage at a temperature of 0–4 °С was within the limits of standards (no more than 1.0×104 CFU/d). It was established that when broiler chickens were given 4.0 g/10 dm3 of water, the MAFAM content for one day of poultry meat storage decreased by 10.4 % (Р < 0.05); on the third day of storage, it decreased by 9.6 % (Р < 0.05); at the beginning of the fifth day of storage, the decrease was, respectively, by 11.3 % (Р < 0.01) compared to the indicators of the control group. The content of MAFAM in offal, in particular in the heart of broiler chickens, was reduced in experimental group 3 by 36.9 % (Р < 0.001); in the liver – by 33.6% (Р < 0.001); in the muscular part of the stomach – by 27.2 % (Р < 0.001); in the spleen and lungs, there was also a decrease in the content of MAFAM in experimental group 3, respectively, by 20.2 % (Р < 0.01) and 23.6 % (Р < 0.01) compared to the indicators of the control group of broiler chickens. It was established that opportunistic pathogenic microorganisms, in particular BGCP, bacteria of the genus Proteus, and pathogenic microorganisms, in specific bacteria of the genus Salmonella, bacteria of the species Staphylococcus aureus, Listeria monocytogenes in 25 grams of the large pectoral muscle of broiler chickens and internal organs (heart, spleen, liver, the muscular part of the stomach and lungs) were not detected. According to the results of the conducted research, an adverse effect of the probiotic biopreparation at a dose of 4.0 g/10 dm3 of water on the development of microorganisms in the large pectoral muscle and internal organs of broiler chickens was established. Therefore, the probiotic “Subtiform” at a dose of 4.0 g/10 dm3 of water during the drinking of broiler chickens can be recommended to increase productivity and obtain safe slaughter products. The practical value of the work consisted of establishing the microbiological indicators of poultry slaughter products after drinking probiotics, as well as establishing safety criteria and the technological process.

With the increasing pursuit of a better life by the public, mining operations need to pay more attention to the adverse effects of blasting vibrations on people and buildings (structures). Based on the measured blasting vibration data in Huibaoling Iron Mine, the attenuation law of blasting vibrations in mines was studied using the Sadaovsk empirical formula. The analysis focused on determining the safe distance for blasting vibrations and identifying the reasonable maximum segment explosive quantity for different mid-section mining operations. This study provides theoretical basis and guidance for the safe mining operations in the mine. The results indicate that there are no safety issues with blasting vibrations for buildings located beyond 1 197.21 m from the working face, while protective objects within the mining area should be positioned approximately 400-500 m away from the blast source. To achieve the peak velocity target of 0.2 cm/s for blasting vibrations, the allowable maximum segment explosive quantity should be con- trolled at around 200 kg. [ABSTRACT FROM AUTHOR]

Feeding broiler chickens a probiotic biopreparation containing bacteria of the genus Bacillus subtilis and Bacillus licheniformis leads to improved feed digestion, increased productivity, and immune status, as well as reduced insemination by opportunistic and pathogenic microorganisms of slaughter products. It enhances the level of prevention and treatment of various poultry diseases. The purpose of the work is to carry out a microbiological analysis of the slaughter products of broiler chickens after drinking the probiotic biological preparation "Subtiform" in doses of 0.5 g, 2.0, and 4.0 g per 10 dm³ of water. The material (major pectoral muscle and internal organs) was examined by bacteriological methods. It was established that the content of MAFAM in the control and experimental groups 1, 2, and 3 of the chilled slaughter products of broiler chickens for 1, 3, and 5 days of storage at a temperature of 0-4 ℃ was within the limits of standards (no more than 1.0×104 CFU/d). It was established that when broiler chickens were given 4.0 g/10 dm3 of water, the MAFAM content for one day of poultry meat storage decreased by 10.4 % (P < 0.05); on the third day of storage, it decreased by 9.6 % (P < 0.05); at the beginning of the fifth day of storage, the decrease was, respectively, by 11.3 % (P < 0.01) compared to the indicators of the control group. The content of MAFAM in offal, in particular in the heart of broiler chickens, was reduced in experimental group 3 by 36.9 % (P < 0.001); in the liver - by 33.6% (P < 0.001); in the muscular part of the stomach - by 27.2 % (P < 0.001); in the spleen and lungs, there was also a decrease in the content of MAFAM in experimental group 3, respectively, by 20.2 % (P < 0.01) and 23.6 % (P < 0.01) compared to the indicators of the control group of broiler chickens. It was established that opportunistic pathogenic microorganisms, in particular BGCP, bacteria of the genus Proteus, and pathogenic microorganisms, in specific bacteria of the genus Salmonella, bacteria of the species Staphylococcus aureus, Listeria monocytogenes in 25 grams of the large pectoral muscle of broiler chickens and internal organs (heart, spleen, liver, the muscular part of the stomach and lungs) were not detected. According to the results of the conducted research, an adverse effect of the probiotic biopreparation at a dose of 4.0 g/10 dm³ of water on the development of microorganisms in the large pectoral muscle and internal organs of broiler chickens was established. Therefore, the probiotic "Subtiform" at a dose of 4.0 g/10 dm3 of water during the drinking of broiler chickens can be recommended to increase productivity and obtain safe slaughter products. The practical value of the work consisted of establishing the microbiological indicators of poultry slaughter products after drinking probiotics, as well as establishing safety criteria and the technological process. [ABSTRACT FROM AUTHOR]

Background: A proper and adequate school environment is important for an effective learning process and for the maintenance of students' health, given that they spend a considerable amount of time at school. Safety preparedness in schools includes, for example, protection from biological, physical, and chemical risks and physical hazards associated with poor construction and maintenance practices. Objectives: This study aims to evaluate safety preparedness in girls’ public schools in the Kingdom of Saudi Arabia (KSA). Methods: Seventeen girls' schools were randomly selected in the Eastern Province of KSA. A designed checklist was used for this study, composed of two main parts. The first part included general information about the school, while the second part was composed of 6 items with a total of 58 questions, evaluating the school's safety preparedness. Results: The safety preparedness in the studied schools ranged between 70 and 90%. Some safety practices were found to be adequately applied, others were poorly applied, and certain items were completely absent. Generally, some examined schools were not compliant several safety and emergency preparedness recommendations. Conclusion: Collaboration between the School Safety Committee and schools is essential to reach a satisfactory standard in terms of school safety. Therefore, it is recommended that the School Safety Committee engages with schools more actively, especially in terms of the preparation of a school safety management plan.

Out-of-the-box swarm solutions powering industrial logistics will need to adapt to the tasks at hand, coordinating in a distributed manner to transport objects of different sizes. This work designs and evaluates a collective transport strategy to move large and arbitrarily shaped objects in warehouse environments. The strategy uses a decentralized recruitment and decision-making process, ensuring that sufficient robots are in place for a coordinated, safe lift and transport of the object. Results show robots having no prior knowledge about the object's size and shape were successfully able to transport them in simulation. [ABSTRACT FROM AUTHOR]

Train derailments in railway switches are becoming more and more common, which have caused serious casualties and economic losses. Most previous studies ignored the derailment mechanism when vehicles pass through the turnout. With this consideration, this work aims to research the 3D derailment coefficient limit and passing performance in turnouts through the quasi-static analysis and multi-body dynamic simulation. The proposed derailment criteria have considered the influence of creep force and wheelset yaw angle. Results show that there are two derailing stages in switch panel, which are climbing the switch rail and stock rail, respectively. The 3D derailment coefficient limit at the region of top width 5 mm to 20 mm is much lower than the main track rail, which shows that wheels are more likely to derail in this area. The curve radius before the switch rail is suggested to be set as 350 m. When the curve radius before turnout is 65 m, the length of the straight line between the curve and turnout needs to be larger than 3 m. This work can provide a good understanding of the derailment limit and give guidance to set safety criteria when vehicles pass through the turnout. [ABSTRACT FROM AUTHOR]

Barrier functions have been reported to be useful in quantifying the safety of some dynamic systems. Usually, when using the barrier functions, we try to transform safety analysis issues of dynamic systems into a class of reachability issues from a safe set to an unsafe set. This article presents a novel sufficient safety criterion for some dynamic systems. The proposed criterion is based on the barrier function and works as long as the upper bound of the barrier function is kept non-positive. Further, we present a mathematical description of fault safety for some dynamic system that experienced a fault at a certain time and propose a corresponding fault safety criterion for the aforementioned system. [ABSTRACT FROM AUTHOR]

How to ensure the underground gas pipe's safety under blasting construction of subway connected aisles is a key problem in tunnel construction. Based on the blasting excavation project of Wuhan Rail Transit Line 8 phase II, the numerical model whose reliability is verified by field monitoring data is established by ANSYS/LS-DYNA to analyze the dynamic underground gas pipe's dynamic characteristics under blasting excavation of the connected aisle. According to the piping design code, the allowable effective stress control standard of underground pipe is proposed to evaluate the underground pipe's safety under the blasting. The results show that: with the advance of blasting excavation, the position of the most dangerous section will change constantly and the pipe's peak particle velocity (PPV) will appear an obvious amplification phenomenon in both sides of metro tunnels. The pipe's PPV is greater than the ground surface's PPV. A mathematical model is established to predict the pipeline's PPV based on the linear relationship between the pipeline and the ground surface. According to the correlation between PPV and von-Mises stress of gas pipeline, a mathematical model between the pipe's von-Mises stress and distance is established to predict the pipeline's safety, which can provide guidance for actual blasting engineering. [ABSTRACT FROM AUTHOR]

The European Union (EU) established the criteria for the classification of shellfish harvesting areas, based on the results of monitoring E. coli in shellfish. The EU also defined E. coli as a microbiological criterion for end product safety, based on a three-class sampling plan. Both criteria are based on the MPN method, a test with a statistical approach and in which different factors contribute to the variability of the outcomes. This theoretical study, based on combinatorics and Bayes' theorem for conditional probability, investigates the consistency between these two criteria and aims to determine the probability of obtaining false compliant and non-compliant results when applying the safety criterion test to shellfish placed on the market. The results show that in the second case, the probability of non-compliant outcomes does not appear negligible within a range between 10% and 50% in the different hypothesized scenarios, with a probability of false noncompliant outcomes over 10%. In addition, the Bayes' Theorem shows that Class A, or Class B areas (as allowed), could be the origin of non-compliant shellfish, with a not negligible frequency. Therefore, within the limits of the assumed working hypotheses, the safety criterion for E. coli, as described in Regulation EC/2073/2005, does not appear to be consistent and coordinated with the classification criteria stated in the Regulation EU/2019/627 and it is not closely related to the sanitary status of shellfish harvesting area. [ABSTRACT FROM AUTHOR]

The European Union (EU) established the criteria for the classification of shellfish harvesting areas, based on the results of monitoring E. coli in shellfish. The EU also defined E. coli as a microbiological criterion for end product safety, based on a three-class sampling plan. Both criteria are based on the MPN method, a test with a statistical approach and in which different factors contribute to the variability of the outcomes. This theoretical study, based on combinatorics and Bayes’ theorem for conditional probability, investigates the consistency between these two criteria and aims to determine the probability of obtaining false compliant and non-compliant results when applying the safety criterion test to shellfish placed on the market. The results show that in the second case, the probability of non-compliant outcomes does not appear negligible within a range between 10% and 50% in the different hypothesized scenarios, with a probability of false noncompliant outcomes over 10%. In addition, the Bayes’ Theorem shows that Class A, or Class B areas (as allowed), could be the origin of non-compliant shellfish, with a not negligible frequency. Therefore, within the limits of the assumed working hypotheses, the safety criterion for E. coli, as described in Regulation EC/2073/2005, does not appear to be consistent and coordinated with the classification criteria stated in the Regulation EU/2019/627 and it is not closely related to the sanitary status of shellfish harvesting area.

This study presents a new hybrid framework based on the multi-criteria decision making in order to rank the potential site layout locations by consideration of the cost and safety criteria in the Mehr Construction Project in Tehran, Iran. To this end, all of the criteria in selecting suitable potential locations are extracted from the research literature and the most effective ones, which are matched with existing conditions in Tehran are considered based on the opinion of experts,. Then, the proper locations for site layout are determined as the potential alternatives and ranked by experts based on the structure. According to the data collected from the questionnaires, the weights of the selected criteria are calculated using Best Worst Method (BWM) and the final ranking of the locations is performed using two Gray Relational Analysis and VIKOR methods. The computational results indicate that both VIKOR and GRA methods yield the same ranking. However, a method with higher reliability should be used to select the best potential location of construction site layout. Therefore, the sensitivity analysis of final outputs on the parameters existing in VIKOR and GRA methods is used in order to rank the alternatives and select the best approach. According to the computational results, the GRA method provides higher robustness compared with the VIKOR method. Accordingly, the ranking obtained from the GRA method is employed as the final solution in implementing the case study.

Abstract Flood water can affect vehicles significantly, which in turn can increase the negative effects of floods as vehicles are washed away by the flow and become a form of debris. In cities, most fatalities during floods occur inside vehicles. Consequently, it is necessary to establish thresholds for vehicle stability during this type of event to provide information necessary for flood risk management. This article analyses the available stability models developed over recent years to determine such thresholds. The stability models were grouped according to the way in which they approached car watertightness and the stability thresholds proposed by each of them were compared. It was found that these thresholds vary over a relatively wide range. Additionally, the experimental data were compared with the results provided by these studies leading to the conclusion that several of the stability models analysed do not fit measured data well. New research is required to overcome the simplifications made by the state‐of‐the‐art models and to try to standardise the decision criteria which should be adopted to define stability thresholds for vehicles of different characteristics.

Studies about electrical current passing through the body such as bioelectricity measurement, electrical excitation, and electrical stimulus have contributed to the field of medical and biological engineering. To evaluate the applicability of the Clinical Trials Act, stimulus conditions are needed to be designed based on the understanding of safety criteria provided by various organizations, as well as the effects of the electricity applied to the human body. Because electrical current causes various effects such as perception, pain, injury, and fibrillation, safety design is essential. This paper summarizes the effects and safety criteria of the electricity applied to the human body based on the available guidelines. Furthermore, effects and criteria of the electricity applied to the head are discussed. Finally, we present an example of the stimulus evaluation to confirm the applicability of the Clinical Trials Act. [ABSTRACT FROM AUTHOR]

Robots are gaining a foothold day-by-day in different areas of people's lives. Collaborative robots (cobots) need to display human-like dynamic performance. Thus, the question of safety during physical human–robot interaction (pHRI) arises. Herein, we propose making serial cobots intrinsically compliant to guarantee safe pHRI via our novel designed device, V2SOM (variable stiffness safety-oriented mechanism). Integrating this new device at each rotary joint of the serial cobot ensures a safe pHRI and reduces the drawbacks of making robots compliant. Thanks to its two continuously linked functional modes—high and low stiffness—V2SOM presents a high inertia decoupling capacity, which is a necessary condition for safe pHRI. The high stiffness mode eases the control without disturbing the safety aspect. Once a human–robot (HR) collision occurs, a spontaneous and smooth shift to low stiffness mode is passively triggered to safely absorb the impact. To highlight V2SOM's effect in safety terms, we consider two complementary safety criteria: impact force (ImpF) criterion and head injury criterion (HIC) for external and internal damage evaluation of blunt shocks, respectively. A pre-established HR collision model is built in Matlab/Simulink (v2018, MathWorks, France) in order to evaluate the latter criterion. This paper presents the first V2SOM prototype, with quasi-static and dynamic experimental evaluations. [ABSTRACT FROM AUTHOR]

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The ESIS Executive Committee decided to nominate a new team for the leadership and management of the TC12/ESIS technical committee (TC), as well as update the TC name as "Risk Analysis and Safety of Large Structures and Components". In this paper, the new organization of the TC12/ESIS as well as the objectives and tasks, and forthcoming events are presented. In addition, this document has editorial purposes regarding the selected and published papers from the International Symposium on Risk Analysis and Safety of Large Structures and Component s (ISRAS-TC12) organized within of the "2nd International Conference of Structural Integrity (ICSI)", which took place at Madeira Island, Portugal, on 4–7 September 2017. As guest editors and TC12/ESIS members, we hope the ISRAS-TC12 Special Issue provides a remarkable impact in the research related to fatigue, fracture, structural integrity, risk analysis and safety of complex structures and components. We also would like to express our gratitude to all authors for their contributions and to all reviewers for their generous work to guarantee the excellence of the papers. Finally, the guest editors would like to express a special thanks to Professor Richard Clegg, Editor-in-Chief of Engineering Failure Analysis journal, and to Elsevier staff for their support during the preparation of this issue. [ABSTRACT FROM AUTHOR]

A mesoscale simulation approach and its corresponding safety criteria are presented to investigate the soil levee instability and its safety criteria. By introducing the particle-flow code (PFC), the numerical simulation tests of levee materials and structures were conducted. Then, the influence of mesoscale particle parameters on macroscale mechanical properties of levee soil was analyzed, and a quantitative relation model of the mesoscale and macroscale material parameters was built. The safety factor, slope instability criterion, and implementation procedure, which the particle-flow code method used to analyze and evaluate the levee slope instability, are given. Finally, the particleflow model of an actual levee was built to simulate and analyze the progressive process from local material damages to the overall slope instability, thereby to investigate the mesoscale mechanism of levee instability. [ABSTRACT FROM AUTHOR]

Coastal ecosystems play an important part in mitigating the effects of climate change. Coastal ecosystems are becoming more susceptible to climate change impacts due to human activities and maritime accidents. The global shipping industry, especially in Southeast Asia, has witnessed numerous accidents, particularly involving passenger ferries, resulting in injuries and fatalities in recent years. In order to mitigate the impact of climate change on coastal ecosystems, this study aimed to evaluate the relationship between employees' perceptions of safety criteria and their own safety behaviour on Langkawi Island, Malaysia. A straightforward random sampling technique was employed to collect data from 112 ferry employees aboard Malaysian-registered passenger boats by administering questionnaires. The findings shed light on the strong connection between providing safety instructions for passengers and safety behaviour among ferry workers. Safety instructions should contain climate-related information to successfully address the effects of climate change. The instructions might include guidance on responding to extreme weather events and understanding the potential consequences of sea-level rise on coastal communities. The ferry company staff should also expand their safe behaviour concept to include training and preparation for climate-related incidents. The need to recognise the interconnectedness between climate change, ferry safety and the protection of coastal ecosystems is emphasised in this study. The findings can be utilised by policymakers, regulatory agencies and ferry operators to design holistic policies that improve safety behaviour, minimise maritime mishaps and preserve the long-term sustainability of coastal ecosystems in the face of difficulties posed by climate change. [Display omitted] • Comprehensive analysis of ferry safety criteria • Integrating marine ecosystem protection with passenger ferry safety • Goal: Reduce incidents, save lives in ferry services • Improved safety for passengers and employees • Simultaneous protection of the marine ecosystem [ABSTRACT FROM AUTHOR]

Robots are gaining a foothold day-by-day in different areas of people’s lives. Collaborative robots (cobots) need to display human-like dynamic performance. Thus, the question of safety during physical human–robot interaction (pHRI) arises. Herein, we propose making serial cobots intrinsically compliant to guarantee safe pHRI via our novel designed device, V2SOM (variable stiffness safety-oriented mechanism). Integrating this new device at each rotary joint of the serial cobot ensures a safe pHRI and reduces the drawbacks of making robots compliant. Thanks to its two continuously linked functional modes—high and low stiffness—V2SOM presents a high inertia decoupling capacity, which is a necessary condition for safe pHRI. The high stiffness mode eases the control without disturbing the safety aspect. Once a human–robot (HR) collision occurs, a spontaneous and smooth shift to low stiffness mode is passively triggered to safely absorb the impact. To highlight V2SOM’s effect in safety terms, we consider two complementary safety criteria: impact force (ImpF) criterion and head injury criterion (HIC) for external and internal damage evaluation of blunt shocks, respectively. A pre-established HR collision model is built in Matlab/Simulink (v2018, MathWorks, France) in order to evaluate the latter criterion. This paper presents the first V2SOM prototype, with quasi-static and dynamic experimental evaluations.

Twenty sodium-cooled fast reactors (SFRs) have provided valuable experience in design, licensing, and operation. This paper summarizes the important safety criteria and safety guidelines of intermediate sodium systems, steam generators, decay heat removal systems and associated construction materials and in-service inspection. The safety criteria and guidelines provide a sufficient framework for design and licensing, in particular by new entrants in SFRs.

The contribution describes probabilistic approach for evaluation of earthing system safety, which can complement the conventional earthing design methodology given by standard EN 50522, similarly as mentioned in British Annex NA. The main part of the contribution is application of the probabilistic risk assessment approach on case study of distribution transformer station earthing system. For presentation of benefits of probabilistic approach, the system solidly earthed, isolated, resonant earthed and resistor earthed were respected as the part of the case study. The contribution stipulates all crucial aspects of this process including probable drawbacks flowing from high amount of non-well known input variables which are necessary for probability calculation, e.g. human body presence, respected risk scenarios, frequency and type of earth faults, fault/contact coincidence, etc. The last part of the contribution is focused on sensitivity analysis of all crucial input variables which can affect final individual risk probability. [ABSTRACT FROM AUTHOR]

Many research reactors are used all over the world. There is a higher probability of accidents in nuclear research reactors compared their wide applications in a broad spectrum of sciences and industries. Material Testing Reactor (MTR) type is one large species of nuclear research reactors. Safety criteria are of main concern issues in the entire nuclear research reactor lifetime to satisfy the defense in depth criteria. In this paper, the main focus is on Second Shutdown System (SSS) as an Engineered Safety Feature (ESF) considered to enhance safety which will transfer the reactor to a subcritical state at actuation of any command circuits when a specific parameters exceeds some pre-established set points. Tehran Research Reactor (TRR) is selected as an MTR case study and one SSS is designed and studied in detail using MCNPX 2.6.0 code with regard to its requirements. It turns out that this SSS improves the overall reactor safety, and has not considerable penalties on different capabilities and characteristics of the reactor such as neutronic characteristics, safety criteria, and performance applications. [ABSTRACT FROM AUTHOR]

In this study, factors relevant to nature-ripened Gouda cheese were evaluated for their potential to inhibit growth of Listeria monocytogenes . Factors included water activity, pH, undissociated acetic and lactic acid, diacetyl, free fatty acids, lactoferrin, nitrate, nitrite and nisin. In addition, the effect of temperature was evaluated. For each factor, the actual concentrations and values relevant to Gouda cheese were obtained and the inhibitory effect of these individual factors on growth of L. monocytogenes was assessed. This evaluation revealed that undissociated lactic acid is the most important factor for growth inhibition of L. monocytogenes in Gouda cheese and that, additionally, low water activity as present in the cheese rind and after prolonged ripening times can also cause full growth inhibition. Gouda cheeses have a typical total lactic acid content of 1.47% w/w. In a 2-week old Gouda cheese, with a pH value of 5.25 and a moisture content of 42% w/w, the concentration of undissociated lactic acid in the water phase is 10.9 mM. Growth of L. monocytogenes is not supported when the undissociated lactic acid concentration is >6.35 mM. Concentrations of undissociated lactic acid in the water phase of Gouda cheese will be higher than this value when the total lactic acid content is >0.86% w/w at a pH < 5.25 (relevant to young Gouda cheese), or >1.26% w/w at a pH < 5.50 for mature Gouda cheese (moisture content of 35% w/w). This study underlines the importance of undissociated lactic acid as growth inhibitor for L. monocytogenes in Gouda cheese. [ABSTRACT FROM AUTHOR]

Speed has been identified for a long time as a key risk factor in road traffic. Inappropriate speeds contribute to a relevant part of road crashes, and then to the mortality and disabilities resulting from them. Starting from this consideration this paper investigates road safety by analysing operating speed, which is the 85th percentile speed. Particularly, two regression models are proposed to predict operating speeds for different road elements related to specific road conditions. The case study is represented by a two-lane rural highway. Smartphone-equipped vehicles were used to evaluate the operating speed for each element of the analysed road segment. Continuous speed data were recorded by the vehicles driven by users with different driving behaviours. Since the lack of safety is often linked to an inconsistency roadway geometric design, we effected a preliminary quantitative design consistency evaluation that confirmed the need of having accurate experimental measures of operating speed or appropriate models for predicting it. We propose two types of operating speed models: one for estimating speed profiles for horizontal curves, and the other one for tangents. According to both models, operating speed is predicted by the combination of an independent variable representing a geometric characteristic (curve radius for the curves and length for the tangent elements) and an independent variable relating to the speed, and specifically the operating speed of the previous road element. The models show a good predictive capability, and can be considered as a useful tool for operators and technicians for road management. First published online: 01 Nov 2015

The proposed technique allows estimating the efficiency of individual elements of hydraulic structures that perform similar functions and work together, and determining the impact of their current state on the entire structure performance. The technique was elaborated for a separate evaluation of drainage and impervious elements of bases of concrete dams on bedrock when they work together. To implement this task, the authors used the method of numerical simulation (modeling) and comparisons with field observations data, which allowed calibrating the ground model. The technique was tested on one of the gates at Bureyskaya HPP, and the influence of drainage and impervious elements effectiveness upon the backpressure on the base of the concrete dam was estimated. The result of these studies allows the authors to suggest appropriate safety criteria K1 and K2. It should be noted that the developed technique allows giving priorities in determining the composition and volume of the repair and / or reconstruction of hydraulic structures elements.

In this study, multi-criteria shape optimization of an asymmetrical doublecurvature arch dam is presented. Simultaneous cost minimization of dam construction and maximum allowable tensile stress are investigated for an economical and safe design approach in the current study. Pareto front method was used to balance both the economy and safety of the design simultaneously, which can be difficult for both analysts and decision-makers. A non-dominated solution based on the important parameters of dam analysis and design is presented. To help decision-makers in their decision, two different methods are proposed. These methods for the case of an arch dam are Lombardi coefficient and equilibrium point methods. The obtained results indicate that these two methods can be helpful for designers without experience and information of previous designs. [ABSTRACT FROM AUTHOR]

Speed has been identified for a long time as a key risk factor in road traffic. Inappropriate speeds contribute to a relevant part of road crashes, and then to the mortality and disabilities resulting from them. Starting from this consideration this paper investigates road safety by analysing operating speed, which is the 85th percentile speed. Particularly, two regression models are proposed to predict operating speeds for different road elements related to specific road conditions. The case study is represented by a two-lane rural highway. Smartphone-equipped vehicles were used to evaluate the operating speed for each element of the analysed road segment. Continuous speed data were recorded by the vehicles driven by users with different driving behaviours. Since the lack of safety is often linked to an inconsistency roadway geometric design, we effected a preliminary quantitative design consistency evaluation that confirmed the need of having accurate experimental measures of operating speed or appropriate models for predicting it. We propose two types of operating speed models: one for estimating speed profiles for horizontal curves, and the other one for tangents. According to both models, operating speed is predicted by the combination of an independent variable representing a geometric characteristic (curve radius for the curves and length for the tangent elements) and an independent variable relating to the speed, and specifically the operating speed of the previous road element. The models show a good predictive capability, and can be considered as a useful tool for operators and technicians for road management. [ABSTRACT FROM AUTHOR]

Background: A proper and adequate school environment is important for an effective learning process and for the maintenance of students' health, given that they spend a considerable amount of time at school. Safety preparedness in schools includes, for example, protection from biological, physical, and chemical risks and physical hazards associated with poor construction and maintenance practices., Objectives: This study aims to evaluate safety preparedness in girls' public schools in the Kingdom of Saudi Arabia (KSA)., Methods: Seventeen girls' schools were randomly selected in the Eastern Province of KSA. A designed checklist was used for this study, composed of two main parts. The first part included general information about the school, while the second part was composed of 6 items with a total of 58 questions, evaluating the school's safety preparedness., Results: The safety preparedness in the studied schools ranged between 70 and 90%. Some safety practices were found to be adequately applied, others were poorly applied, and certain items were completely absent. Generally, some examined schools were not compliant several safety and emergency preparedness recommendations., Conclusion: Collaboration between the School Safety Committee and schools is essential to reach a satisfactory standard in terms of school safety. Therefore, it is recommended that the School Safety Committee engages with schools more actively, especially in terms of the preparation of a school safety management plan., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Mahmoud Fathy Mohamed Elsharkawy reports administrative support was provided by 10.13039/501100015090Imam Abdulrahman Bin Faisal University. Mahmoud Fathy Mohamed Elsharkawy reports a relationship with Imam Abdulrahman Bin Faisal University that includes: employment. Mahmoud Fathy Mohamed Elsharkawy has patent pending to Licensee. No conflict of Interest., (© 2023 The Authors.)