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Suggests that the discussion of online payments, while ultimately being a key issue for the future Information SuperHighway, is as significant now as it ever will be. The explosive increase in the use of the Internet has seen the emergence of commercial services and pressures previously restricted to Compuserve and the like. Many predictions see this burgeoning electronic marketplace becoming a significant component of the world economy. However, this can only happen once two key problems have been addressed, namely, protecting property rights, and making payments. This has led to a frantic battle for payment mechanisms that can provide the new medium with the means of conducting transactions. Identifies the key commercial requirements that successful use of the Internet will impose on a payment mechanism. Identifies the different types of mechanisms that are proposed, on trial or in use on the Internet. Evaluates each of these mechanisms against the requirements to determine which (if any) are really suitable for electronic commerce.

The purpose of this study is to establish a systematic framework to characterise the safety of air routes, in terms of separation minima infringements (SMIs) between en-route aircraft, based on the definition of models known as safety performance functions.

Techniques with high predictive capability were selected that enable both expert knowledge and data to be harnessed: Bayesian networks. It was necessary to establish a conceptual framework that integrates the knowledge currently available on the causality and precursors of SMIs with the hindsight derived from the analysis of the type of data available. To translate the conceptual framework into a set of causal subnets, the concepts of air traffic management (ATM) barrier model and event trees have been incorporated.

The model combines analytics and insights, as well as predictive capability, to answer the question of how airspace separation infringements are produced and what their frequency of occurrence will be. The main outputs of the network are the predicted probability of success for the ATM barriers and the predicted probability distribution of the vertical and horizontal separation of an aircraft in its closest point of approach.

The main contribution of this work is that, by virtue of the calculation capacity obtained, the network can be used to draw conclusions about the impact that a modification of the airspace and of the traffic, or operational conditions, would have on the effectiveness of the barriers and on the final distributions of distance between aircraft in the CPA, thereby estimating the probability of SMI.

The purpose of this paper is to evaluate the safety of formation flying satellites, and propose a method for practical collision monitoring and collision avoidance manoeuvre.

A general formation description method based on relative orbital elements is proposed, and a collision probability calculation model is established. The formula for the minimum relative distance in the crosstrack plane is derived, and the influence of J2 perturbation on formation safety is analyzed. Subsequently, the optimal collision avoidance manoeuvre problem is solved using the framework of linear programming algorithms.

The relative orbital elements are illustrative of formation description and are easy to use for perturbation analysis. The relative initial phase angle between the in‐plane and cross‐track plane motions has considerable effect on the formation safety. Simulations confirm the flexibility and effectiveness of the linear programming‐based collision avoidance manoeuvre method.

The proposed collision probability method can be applied in collision monitoring for the proximity operations of spacecraft. The presented minimum distance calculation formula in the cross‐track plane can be used in safe configuration design. Additionally, the linear programming method is suitable for formation control, in which the initial and terminal states are provided.

The relative orbital elements are used to calculate collision probability and analyze formation safety. The linear programming algorithms are extended for collision avoidance, an approach that is simple, effective, and more suitable for on‐board implementation.

Safety‐related fieldbus is now being employed in many varied applications. Developments in fieldbus technology and programmable systems, coupled with developments in International and European Standards have created the opportunity for widespread use. Performance, equipment availability, flexibility, diagnostics and reduced cost of ownership are the principal reasons for rapid growth in safety‐related networking. The use of programmable safety systems has fundamentally have changed the way in which safety is now being engineered in the manufacturing plant. New devices provide direct connectivity to safety‐related networks, increasing the scope and changing the architecture of safety systems far beyond conventional expectations. Technological developments, application and benefits of safety‐related networking in industrial automation systems are shown. Criteria for safety network selection are highlighted.

This study aims to create 6-degree of freedom (SDOF) for computational fluid dynamics (CFD) simulations of body movement, and to validate using the experimental data for empty tank separation from I-22 Iryda jet trainer. The procedure has an ability to be modified or extended, to simulate, for example, a sequential release from the joints.

A set of CFD simulations are calculated. Both the SDOF procedure and the CFD simulation settings are validated using the wind tunnel data available for the aircraft.

The simulation using designed procedure gives predictable results, but offers availability to be modified to represent external forces, i.e. from body interaction or control system without necessity to model the control surfaces.

The procedure could be used to model the separation of external stores and design the deployment of anti-radar chaff, flares or ejection seats.

The work presents original work, caused by insufficient abilities of original SDOF procedure in ANSYS code. Additional value is the ability of the procedure to be easily modified.

Highlights Norwegian regulatory framework with its employee participation tradition. Posits a response of the UK government was the introduction of new offshore regulations with a required need for safety meetings and elected safety representatives. Recognizes, in Canada, that moving into the production phase of the offshore oil industry triggered a renewed interest in offshore safety. Concludes Norway’s amended offshore oil and gas regulations of 1998 placed heavy emphasis on workers’ input to enable all the changes to take place in a correct manner.

A number of automated tools will be required for the purpose of enabling efficient services in air traffic control. The purpose of this paper is to devise an optimal flight trajectory search method that optimizes airspace system efficiency for 3D space in the presence of uncertainties.

This paper put forward an optimization model for generating applicable solutions of multi-aircraft conflict resolution problem, and the solution is based on the principle of optimality.

The conflict resolution problem between multiple aircraft can be described by spatial discretization, and the approach taken digitizes the 3D space into a grid of nodes.

The simulation examples are given to illustrate the validity of trajectory search model and stress on the impact of different system parameters.

Realistic constraints that are convenient to operate are incorporated in the system model, and the results show that it can provide reliable decision-making for conflict avoidance.

The purpose of this paper is to explore the enactment of safety routines in a transshipment port. Research on work safety and reliability has largely neglected the role of the workers’ knowledge in practice in the enactment of organisational safety. The workers’ lack of compliance with safety regulations represents an enduring problem that often involves first-level managers, who are willing to turn a blind eye toward divergent practices. The CHAT conceptual vocabulary and theoretical model is used to explore this issue.

A grounded, empirical study in a large transshipment port in the Mediterranean area is conducted. Ethnographic methods including participant observation and interviews are used, and emerging data are analyzed through an interpretive methodology. The paper explores 30 employees’ narrated accounts of how safety rules are enacted or infringed while living and working in the field in a transshipment port. Data obtained through organisational shadowing provided secondary data. Interview data were analyzed using content analysis, using a CHAT framework. Constant comparison and theoretical sensitivity were pursued through an iterative analysis process.

This study documented the critical role the workers’ knowledge played in practice in ensuring the efficient functioning of the port, and evidenced that the disconnect between safety procedures and technical productivity standards is the most important factor determining the erratic compliance with prescribed procedures. The selective application of safety norms was deliberate in nature, collectively shared and culturally regulated.

This contribution fails to address probably the most important aspect of the activity theoretical approach: its developmental orientation. The initial analysis intervention was meant to lead to a longitudinal process of expansive learning and development in the activity system. The authors had planned to initiate a cycle of expansive learning laboratories involving representatives of the dockworkers, the port management and the safety certification firm, but this had to be postponed to an undefined time due to the significant changes occurred in the international maritime cargo industry and the decision of the multinational company who owns the transshipment port to cut down its cargo traffic and privilege other ports in the Mediterranean area.

The practical implications of the case study concern the conception and design of safety training and management for the port organisation. By acknowledging the disconnect between espoused safety routines and the constraints and affordances of the workers’ everyday work practice, it is suggested that safety training could be more effective if it engaged the workers (or first-level supervisors) in the fine tuning of safety regulations. Workplace learning opportunities could enable the workers to learn and construct situated safety practices.

This paper seeks to highlight how the consideration of local knowledge and context-dependent practices can achieve better comprehension of situated application of safety norms.

The paper contributes to understanding the complexity of enacting and translating safety procedures into everyday work practices.