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This paper aims to assess the implications in safety levels by the integration of remotely piloted aircraft system (RPAS). The goal is to calculate the number of RPAS that can jointly operate with conventional aircraft regarding conflict risk, without exceeding current safety levels.

This approach benchmarks a calculated level of safety (CLS) with a target level of safety (TLS). Monte Carlo (MC) simulations quantify the TLS based on the current operation of conventional aircraft. Then, different experiments calculate the CLS associated with combinations of conventional aircraft and RPAS. MC simulations are performed based on probabilistic distributions of aircraft performances, entry times and geographical distribution. The safety levels are based on a conflict risk model because the safety metrics are the average number of conflicts and average conflict duration.

The results provide restrictions to the number of RPAS that can jointly operate with conventional aircraft. The TLS is quantified for four conventional aircraft. MC simulations confirm that the integration of RPAS demands a reduction in the total number of aircraft. The same number of RPAS than conventional aircraft shows an increase over 90% average number of conflicts and 300% average conflict time.

The methodology is applied to one flight level of en-route airspace without considering climbing or descending aircraft.

This paper is one of the most advanced investigations performed to quantify the number of RPAS that can be safely integrated into non-segregated airspace, which is one of the challenges for the forthcoming integration of RPAS. Particularly, Europe draws to allow operating RPAS and conventional aircraft in non-segregated airspace by 2025, but this demanding perspective entails a thorough analysis of operational and safety aspects involved.

Previous research studies have testified that safety culture positively affects safety performance. However, the progression by which safety culture affects safety performance has not yet been examined. Also, how safety culture affects the overall safety performance at different levels of the organization is yet to be explored. In order to address this issue, the purpose of this paper is to study the effect of multilevel safety culture upon safety performance over time.

A conceptual causal-loop diagram is constructed using the group model building approach to establish the relationship between safety culture components (e.g. psychological, behavioral and situational) and the factors associated with safety performance (e.g. risk level, safety behavior, unsafe conditions, unsafe acts and incident rate). Considering the dynamic nature and intricacy of the safety management system, the system dynamics approach has been employed to develop the model.

The results indicate that the safety culture at the tactical level (middle management) and operational level is much more effective than strategic level (top management) in ameliorating the safety performance of the organization.

The scope of this study is limited to the effect of multilevel safety culture on safety performance. The focus is on the dynamics of personal, behavioral and situational factors of top management, middle management and workers to reinforce the safety performance of the organization. Future research can be protracted to build other models of safety.

First and foremost, the findings summarized in this paper can be implemented by organizations to achieve the total safety culture to upgrade safety performance.

This paper presents the holistic view of multilevel safety culture in an organization’s hierarchy. It shows how multilevel level safety culture in an organization interacts with the safety management system to enhance the safety performance of the organization.

This paper aims to investigate the state of the art for the reliability evaluation of reinforced concrete beams in a fire situation. Special emphasis is placed on addressing which parameters were considered probabilistically or deterministically, the prescribed probabilistic models for the assumed stochastic variables, the treatment of the heat transfer mechanism, the quantification of the structural fire performance and the assumed target reliability levels.

Research papers were identified through a search on the Web of Science, Google Scholar and detailed searches within the journals Journal of Structural Fire Engineering, Fire Technology and Fire Safety Journal, supplemented with references known by the authors.

Considering the state-of-the-art review, gaps in the literature are identified related to (1) the probabilistic evaluation of shear capacity for standard fires and parametric fires, and bending capacity for parametric fires, (2) the absence of reference fragility curves for immediate design application/code calibration and (3) the specification of target safety levels for reliability-based design.

The lack of research papers gathering studies on the reliability of reinforced concrete beams in fire situation makes it difficult to further develop research in the area. The value of this work lies precisely in the collection of the basic information, making it possible to identify gaps to be addressed in future research and the suggestion of a research framework.

Using the large database of patent, the purpose of this paper is to structure a technology convergence network using various patent network analysis for integrating different results according to network characteristics.

The patent co-class analysis and the patent citation analysis are applied to discover core safety fields and technology, respectively. In specific, three types of network analysis, which are centrality analysis, association rule mining analysis and brokerage network analysis, are applied to measure the individual, synergy and group intensity.

The core safety fields derived from three types of network analysis used by different nature of data algorithms are compared with each other to understand distinctive meaning of cores of patent class such as medical safety, working safety and vehicle safety, differentiating network structure. Also, to be specific, the authors find the detailed technology contained in the core patent class using patent citation network analysis.

The results provide meaningful implications to various stakeholders in organization: safety management, safety engineering and safety policy. The multiple patent network enables safety manager to identify core safety convergence fields and safety engineers to develop new safety technology. Also, in the view of technology convergence, the strategy of safety policy can be expanded to collaboration and open innovation.

This is the initial study on applying various network analysis algorithms based on patent data (class and citation) for safety management. Through comparison among network analysis techniques, the different results are identified and the collective decision making on finding core of safety technology convergence is supported. The decision maker can obtain the various perspectives of tracing technology convergence.

Managing a safety programme and ensuring that change is in accordance with suitable performance measures requires continuing improvement in the support of analytical power and empirical information. This paper aims to consider different approaches and modeling efforts on safety performance evaluation.

Review and synthesis of literature.

Ten major safety performance evaluation approaches are identified including expectation function, risk assessment, statistical quality control, price deflation, engineering economic factor, system analysis, artificial intelligence, and systems theory. Based on the approaches, quantitative and qualitative models have been proposed. The quantitative models use measuring indicators such as frequency, severity, percentages, relative weight and economic gains/loss of safety programme. However, qualitative models employ hazard analysis and hazard operability.

Several research questions remain to be answered in order to completely improve and optimize the impact of these provisional safety performance measures.

This study offers a set of interesting lessons for academics, industry and safety practitioners by providing guidelines that will assist in ensuring a correct focus to select an appropriate safety performance evaluation model.

The purpose of this paper is to calculate the probability of collision of flying aircraft crossing on straight paths in any direction.

The probability of deviations from the intended flight paths is used to calculate the probability of collision that is integrated over time to cover whole events.

The probabilities of collision are calculated in terms of the r.m.s. position errors and encounter geometry, that is aircraft velocities and flight path angles and crossing angles.

The method does not apply to aircraft flying in parallel tracks at the same velocity in air corridors: that case has been covered elsewhere, as well as the case of climbing or descending aircraft.

International Civil Aviation Organization (ICAO) specifies as target level of safety (TLS) a probability of collision not exceeding 5×10⁻⁹ per hour. To meet the ICAO TLS standard, it is necessary to calculate collision probabilities for all stages of flight.

A low collision probability is a safety metric; the value does depend on a realist choice of probability distribution.

Calculates the probability of collision for crossing flights, corresponding to a common scenario on air traffic management.

The paper aims to investigate the compatibility of manned-aircraft airborne collision avoidance systems (ACAS) for use on unmanned aerial vehicles (UAV).

The paper uses the Fault Tree method for defining ACAS model adapted for the UAV operations, with the aim of showing the presence of certain factors that configure in such ACAS system, and whose failure can lead to an adverse event – mid-air collision.

Based on the effectiveness analysis of ACAS solution adapted for the UAV operations, for given inputs, it can be concluded that the probability of ACAS failure is on the order of 10–4, as well as that in the case of autonomous ACAS solution for the UAV, the probability is reduced to 10–5. The most influential factors for the failure of the UAV’s ACAS are as follows: technical implications on the UAV, human factor, sensor error, communication and C2 link issue.

The established model could be used both in the UAV’s ACAS design and application phases, with the aim of assessing the effectiveness of the adopted solution. The model outputs not only highlight the critical points of the system but also provide the basis for defining the Target Level of Safety (TLOS) for the UAV operations.

The developed model can be expected to speed up the design and adoption process of ACAS solutions for the UAVs. Also, the paper presents one of the first attempts to quantify TLOS for the UAV operations in the context of collision avoidance systems.

A model of an electronic data interchange (EDI) enabled ingredient supply chain for a food processing company was developed, the model was simulated and its performance was compared with a simulation model of the current ingredient supply chain process of a US food processing company. The simulation results indicated that an EDI enabled system, which removed many of the time delays associated with the current process, significantly reduced swings in raw materials inventory and allowed significant reductions in raw materials safety stock without increasing the risk of production delays due to out‐of‐stock ingredients.

The purpose of this paper is to study the overall framework in which the Urban Air Mobility (UAM) deployment is expected to be implemented. Another aim of the study is to give a better overview on the current regulations and standards including the impact of the regulations on the industry, operations and cities.

This paper performs a literature review on the regulatory framework, which provides a clear view of the current regulations and standards. The review includes the insight into the details of possible international rules for the future, considering operations in the specific and certified categories. The impact and trends of current and future regulations are also presented.

The analysis described in this paper shows a strong upward trend in UAM technical and operational developments as well as further potential for a successful incorporation in city mobility concepts. This paper indicates the importance of the representatives of guideline development organizations, industry, agencies and other important players involved in the standard development process.

This section describes synthesis on the required level of safety for UAM operations as well as description on the impact of the regulations from different perspectives, including industry and certification of urban aircraft, operations and air traffic management, cities and the governance of the urban airspace and well as technology.

Barriers such as legislation do not allow the common UAM to be deployed. This paper studies the overall framework in which the UAM deployment is expected to be implemented.

The purpose of this paper is to improve risk assessment processes in airline flight operations by introducing a dynamic risk assessment method.

Fuzzy logic and Bayesian network are used together to form a dynamic structure in the analysis. One of the most challenging factors of the analyses in aviation is to get quantitative data. In this study, the fuzzy data quantification technique is used to perform dynamic risk assessment. Dynamic structure in the analysis is obtained by transforming the bow-tie model into a Bayesian network equivalent.

In this study, the probability of top-event from fault tree analysis is calculated as 1.51 × 10⁻⁶. Effectiveness of the model is measured by comparing the analysis with the safety performance indicator data that reflects past performance of the airlines. If two data are compared with each other, they are at the same order of value, with small difference (0.6 × 10⁻⁷).

This study proposes a dynamic model to be used in risk assessment processes in airline flight operations. A dynamic model for safety analysis provides real-time, autonomous and faster risk assessment. Moreover, it can help in the decision-making process and reduce airline response time to undesired states, which means that the proposed model can contribute to the efficiency of the risk management process in airline flight operations.