As world transport has grown in complexity, so has public pressure for safe flight. The scheduled airline industry has a consistently good safety record. Unfortunately, the business jet industry has not kept pace with the airline safety statistics and lags far behind. During safety surveys and reports over the past 5 years there has been increasing comment and concern over the perceived safety standards of business jets operations compared with normal scheduled airline services. The UK Civil Aviation Authority (CAA) has reported that based on flight hours flown, the fatal accident rate for smaller jet aircraft below 15 tonnes was twice that for large passenger aircraft (CAA 2006a). The CAA also identified that the majority of the accidents occur during the approach and landing phase of the flight. There is however, a lack of research concerning business jet operations. Due to the unique and varied style of operations, business jet flights have many factors that differentiate it from normal scheduled airline operations. Business jet accidents have been reported but they have not been further investigated for any overall causes. The study described in this thesis, a Grounded Theory analysis of accident data was conducted to develop a model of the factors that contributed to the accidents. The model that was developed demonstrated that Pilot skills, Command and Crew Resource management are the key central elements, with the ground organisations such as engineering and ground operations personnel as a contributory influence. As piloting skills were determined as a key factor in the accident statistics and the accident model, a simulator trial was also conducted to assess the manual flying skill levels of business jet pilots. The trial was both a challenging manual flying task and a profile that is included as part of the Pilot Skill test prior to the issue of a commercial pilot’s licence. The simulator trial confirmed that although all the pilots were correctly tested and certified commercial pilots, a significant proportion did not fly an accurate airspeed on approach within the CAA examination tolerances. The simulator trial data and the grounded theory model found that there are concerns for the piloting skills of business jet pilots in their ability to fly an accurate airspeed on approach. The results from this investigation yield findings concerning the piloting skill and accuracy of the business jet pilots that had not previously been identified. The results also emphasise the need to include adequate testing and supervision during business jet operations. It is recommended that further research be conducted to evaluate actual piloting skill and accuracy during the licence skill test.

In order to enhance safety and prevent the recurrence of major accidents it is necessary to understand why they occur. This understanding is gained by utilising accident causation theory to explain why a certain combination of events, conditions and actions led to a given outcome: the process of accident analysis. At present, the systems approach to accident analysis is arguably the dominant research paradigm. Based on the concepts of systems theory, it views accidents as the result of unexpected and uncontrolled relationships between a system s components. Various researchers claim that use of the systems approach, via systemic accident analysis, provides a deeper understanding of accidents when compared with traditional theories. However, the systems approach and its analysis techniques are yet to be widely adopted by the practitioner community and, therefore, a research-practice gap exists. The implication of such a gap is that practitioners may be applying outdated accident causation theory and, consequently, producing ineffective safety recommendations. The aim of this thesis was to develop the current understanding of the systemic accident analysis research-practice gap by providing a description of the gap, considering its extent and examining issues associated with bridging it. Four studies were conducted to achieve this aim. The first study involved an evaluation of the systemic accident analysis literature and techniques, in order to understand how their characteristics could influence the research-practice gap. The findings of the study revealed that the systems approach is not presented in a consistent or clear manner within the research literature and that this may hinder its acceptance by practitioners. In addition, a number of issues were identified (e.g. model validation, analyst bias and limited usage guidance) which may influence the use of systemic analysis methods within industry. The examination of how the analysis activities of practitioners may contribute to the gap motivated Study 2. This study involved conducting semi-structured interviews with 42 safety professionals and various factors, which affect the awareness, adoption and usage of the systems approach and its analysis methods, were highlighted. The combined findings of Studies 1 and 2 demonstrate that the systemic accident analysis research-practice gap is multifaceted in nature. Study 3 investigated the extent of the gap by considering whether the most widely used analysis technique (the Swiss Cheese Model) can provide a systems approach to accident analysis. The analysis of a major rail accident was performed with a model based on the Swiss Cheese Model and two systemic analysis methods. The outputs and usage of the three analysis tools were compared and indicate that the Swiss Cheese Model does provide a means of conducting systemic accident analysis. Therefore, the extent of the research-practice gap may not be as considerable as some proponents of the systems approach suggest. The final study aimed to gain an insight into the application of a systemic accident analysis method by practitioners, in order to understand whether it meets their needs. Six trainee accident investigators took part in an accident investigation simulation and subsequently analysed the data collected during the exercise with the Systems Theoretic Accident Modelling and Processes model. The outputs of the participants analyses were studied along with the evaluation feedback they provided via a questionnaire and focus group. The main findings of the study indicate that the analysis technique does not currently meet the usability or graphical output requirements of practitioners and, unless these issues are addressed, will struggle to gain acceptance within industry. When considering the research findings as a whole a number of issues are highlighted. Firstly, given the benefits of adopting the systems approach, efforts to bridge the systemic accident analysis research-practice gap should be made. However, the systemic analysis methods may not be best suited to analyse every type of accident and, therefore, should be considered as one part of an investigator s analysis toolkit . Adapting the systemic analysis methods to meet the needs of practitioners and communicating the systems approach more effectively represent two options for bridging the gap. However, due to the multidimensional nature of the gap and the wide variety of individuals, organisations and industries that perform accident analysis, it seems likely that tailored solutions will be required. Furthermore, due to the differing needs of the research and practice communities, efforts to bridge the gap should focus on collaboration between the two communities rather than attempting to close the gap entirely.

This thesis examines the application of Systems-Theoretic Accident Model and Processes (STAMP) in healthcare and the analysis of patient safety incidents. Healthcare organisations have a responsibility for the safety of the patients they are treating. This includes the avoidance of unintended or unexpected harm to people during the provision of care. Patient safety incidents, that is adverse events where patients are harmed, are investigated and analysed as accidents are in other safety-critical industries, to gain an understanding of failure and to generate recommendations to prevent similar incidents occurring in the future. However, there is some dissatisfaction with the current quality of incident analysis in healthcare. There is dissatisfaction with the recommendations that are generated from healthcare incident analysis which are felt to produce weak and ineffective remedial actions, often including retraining of individuals and small policy change. Issues with current practice have been linked to the use of Root Cause Analysis (RCA), an analysis method that often results in the understanding of an accident as being the result of a linear chain of events. This type of simple linear approach has been the target of criticism in safety science research and is not felt to be effective in the analysis of incidents in complex systems, such as healthcare. Research in accident analysis methods has developed from a focus on technical failure and individual human actions to consideration of the interactions between people, technology and the organisation. Accident analysis methods have been developed that guide investigations to consideration of the whole system and interactions between system components. These system approaches are judged to be superior to simple linear approaches by the research community, however, they are not currently used in healthcare incident investigation practice. The systems approach of STAMP is felt to be a promising method for the improvement of healthcare incident analysis. STAMP strongly embodies the concepts of systems theory and analyses human decision-making. The application of STAMP in healthcare was investigated through three case studies, which applied STAMP in: 1. The analysis of the large-scale organisational failure at Mid-Staffordshire NHS Trust between 2005-2009. 2. The analysis of a common small-scale hospital-based medication prescription error. 3. The analysis of patient suicide in the community-based services of a Mental Health Trust. The effectiveness of the STAMP applications was evaluated with feedback from healthcare stakeholders on the usability and utility of STAMP and discussion of the STAMP applications against criteria for accident analysis models and methods. Healthcare stakeholders were generally positive about the utility of STAMP, finding it to provide a system view and guide consideration of interactions between system components. They also felt it would help them generate recommendations and were positive about the future application of STAMP in healthcare. However, many felt it to be a complicated method that would need specialist expertise to apply. The STAMP applications demonstrated the ability of STAMP to consider the whole system and guide an analysis to the generation of recommendations for system measures to prevent future incidents. From the findings of the research, recommendations are made to improve STAMP and to assist future applications of STAMP in healthcare. The research also discusses the other factors that influence incident analysis beyond that of the analytical approach used and how these need to be considered to maximise the effectiveness of STAMP.

No description available.

The main purpose of the thesis is to discuss the accident models which underlie accident prevention in general and road safety in particular, and the consequences of relying on a particular model have for actual preventive work. The discussion centres on two main topics. The first topic is whether the underlying accident model, or paradigm, of traditional road safety should be exchanged for a more complex accident model, and if so, which model(s) are appropriate. From a discussion of current developments in modern road traffic, it is concluded that the traditional accident model of road safety needs replacing. An analysis of three general accident model types shows that the work of traditional road safety is based on a sequential accident model. Since research in industrial safety has shown that such model are unsuitable for complex systems, it needs to be replaced by a systemic model, which better handles the complex interactions and dependencies of modern road traffic. The second topic of the thesis is whether the focus of road safety should shift from accident investigation to accident prediction. Since the goal of accident prevention is to prevent accidents in the future, its focus should theoretically be on how accidents will happen rather than on how they did happen. Despite this, road safety traditionally puts much more emphasis on accident investigation than prediction, compared to areas such as nuclear power plant safety and chemical industry safety. It is shown that this bias towards the past is driven by the underlying sequential accident model. It is also shown that switching to a systemic accident model would create a more balanced perspective including both investigations of the past and predictions of the future, which is seen as necessary to deal with the road safety problems of the future. In the last chapter, more detailed effects of adopting a systemic perspective is discussed for four important areas of road safety, i.e. road system modelling, driver modelling, accident/incident investigations and road safety strategies. These descriptions contain condensed versions of work which has been done in the FICA and the AIDE projects, and which can be found in the attached papers.

No description available.

This thesis proposes an estimation approach for count data models with endogenous covariates. The maximum approximate composite marginal likelihood inference approach is used to estimate model parameters. The modeling framework is applied to predict crash frequency at urban intersections in Irving, Texas. The sample is drawn from the Texas Department of Transportation crash incident files for the year 2008. The results highlight the importance of accommodating endogeneity effects in count models. In addition, the results reveal the increased propensity for crashes at intersections with flashing lights, intersections with crest approaches, and intersections that are on frontage roads. / text

Railway suicide constitutes a limited but significant fraction of all suicides, and a majority of all railway-related deaths, in Sweden as well as in many other countries. The aim of this thesis is to develop the scientific basis for the prevention of railway suicide, with special regard to knowledge and strategies within the reach of the railway system owners themselves. An initial descriptive epidemiologic study showed that railway suicide episodes cluster in densely populated areas, and that victims often seem to await approaching trains for some time on or close to tracks before being hit. This means that preventive efforts can be prioritized to geographically limited areas and that there exists a time margin for early detection, forewarning, braking, rescuing, and the like. Secondly, a theoretical study was conducted in order to derive an overview of theoretically possible barriers aimed at preventing railway suicide. The approach is based on the comparison and synthesis of theories and models from suicidology and safety sciences applied to the railway suicide phenomenon. This led to a list of possible barriers, also intended as a checklist. This was followed by a multiple case study, where a number of authentic cases were analysed in-depth on the basis of investigation reports by the police and railway officials, plus complementary researcher observations from the actual sites of the suicide occurrences. The study revealed some deficiency in current investigation and reporting routines from a preventative viewpoint and indicated the potential for a broader and more systematic collection of prevention-relevant information in immediate connection with the events. Finally, a focus group study, involving safety practitioners from both the railway and other sectors, confirmed a general understanding and acceptance among practitioners of the theoretically derived principles, and a readiness to broaden the scope of railway safety to include approaches to prevent suicide. In conclusion, it should be possible to influence the occurrence of railway suicides by means available within the railway transport system itself. A spectrum of possible alternative barriers is identified, as well as an, as yet, underutilized potential in the form of more systematic data collection and learning routines from actual events. Last but not least, there is a readiness among practitioners to incorporate these principles in regular railway safety work.

Submitted by Almir Azevedo (barbio1313@gmail.com) on 2014-05-22T16:36:29Z No. of bitstreams: 1 dissertacao_mestrado_ien_2013_04 Renato Raoni.pdf: 2604427 bytes, checksum: ad33731b6c51a6c4e9e1abb26b746f83 (MD5) / Made available in DSpace on 2014-05-22T16:36:29Z (GMT). No. of bitstreams: 1 dissertacao_mestrado_ien_2013_04 Renato Raoni.pdf: 2604427 bytes, checksum: ad33731b6c51a6c4e9e1abb26b746f83 (MD5) Previous issue date: 2013-03 / Estudos de transferência de calor em varetas combustível são de grande importância na indústria nuclear. Isso se evidencia pela necessidade da predição de temperaturas limite para otimizar o projeto de varetas combustível. O presente trabalho tem por objetivo o desenvolvimento de um código computacional em linguagem fortran, no qual estão reunidas ferramentas como o Método de Elementos Finitos. Equações e correlações termo-hidráulicas foram implementadas no código com vistas a uma investigação profunda da transferência de calor entre a vareta combustível e o canal refrigerante, buscando, assim, entender o comportamento de ambos em regime transiente (como, por exemplo, nas situações de acidente). Foi feita uma análise sobre a validade da aproximação que desconsidera o fluxo axial de calor nas soluções analíticas. Comparações entre as soluções utilizando as propriedades constantes e propriedades dependentes da temperatura forma contempladas nesse trabalho. Estudos transientes envolvendo o desligamento do reator, considerando aspectos como a temperatura limite do combustível e o Departure from Nucleate Boiling Ratio (BNBR), foram realizados produzindo resultados que podem demonstrar o desempenho do código computacional / Studies on heat transfer fuel rods are of great importance in the nuclear industry . This is evidenced by the need for prediction of temperature limits to optimize the design of fuel rods . This work aims to develop a computer code in FORTRAN language, in which are gathered tools such as Finite Element Method . Equations and thermo- hydraulic correlations were implemented in the code with a view to a thorough investigation of heat transfer between the fuel rod and coolant channel , seeking thereby to understand the behavior of both in transient ( eg , in cases of accident ) . An analysis of the validity of the approach that disregards the axial heat flow in the analytical solutions was taken . Comparisons between solutions using constant properties and temperature dependent properties manner contemplated in this work . Transient studies involving the reactor shutdown , considering aspects such as limit the fuel temperature and Departure from nucleate Boiling Ratio ( BnBr ) , were performed yielding results that can demonstrate the performance of the computer code

The dissertation thesis focuses on the problem of driver inattention as one of the main factors contributing to the traffic accidents occurrence. The importance of this topic has been introduce on the basis of the literature review. The theoretical analysis includes terminology in the field of accident analysis related to the topic of this dissertation thesis. Existing methods for driver behavior analysis have been introduced as well as the selected resuls of existing research studies focused on the driver inattention. Research gaps have been identified on the basis of the research review, on some of them has been focused this work. The defined problem situation points to the need to find and verify the relevant modern methods for analysis of driver inattention, respectivaly influence of selected distracting stimuli on the stages of driver information processing. The series of measurements also provides quantified data, especially with regard to the perception duration of selected distracting stimuli.