There have been some correlations in the literature to predict the gas and liquid flow rate through wellhead chokes under subcritical flow conditions. The majority of these empirical correlations ...have been developed based on limited production data sets that were collected from a small number of fields. Therefore, these correlations are valid within the parameter variation ranges of those fields. If such correlations are used elsewhere for the prediction of the subcritical choke flow performance of the other fields, significant errors will occur. Additionally, there are only a few empirical correlations for sub-critical choke flow performance in high rate gas condensate wells. These led the authors to develop a new empirical correlation based on a wider production data set from different gas condensate fields in the world; 234 production data points were collected from a large number of production wells in twenty different gas condensate fields with diverse reservoir conditions and different production histories. A non-linear regression analysis method was applied to their production. The new correlation was validated with a new set of data points from some other production wells to confirm the accuracy of the established correlation. The results show that the new correlation had minimal errors and predicted the gas flow rate more accurately than the other three existing models over a wider range of parameter variation ranges.
•A statistical analysis of 1207 marine accidents worldwide from 2010 to 2019.•A critical literature review on previous studies on marine accident severity.•A study on the relationship between the ...influencing factors and accident severity.•Provision of recommendations for the improvement of maritime safety.
This study aims to explore the relationship between the severity of marine accidents and influencing factors. An ordered logistic regression model is used to reflect the relationship between these factors and the severity of marine accidents using the worldwide accident investigation reports in the period of 2010–2019. The obtained results show that the marine accident severity is positively associated with sinking accidents, far away from port, strong wind, heavy sea, strong current and/or good visibility. With respect to ship types, fishing vessels, yachts and sailing vessels, and other ship types are the ship types most involved in accidents of higher severity. The severity level is higher for ships having incomplete or invalid seafarers’ certificates, inadequate ship manning, incomplete or invalid ship certificates and/or over 30 years of age. Seafarers with poor theoretical knowledge and less sea experience are more likely to be involved in accidents of serious consequences. Small water depth and ship types such as chemical tankers, oil tankers, container ships and/or bulk carriers are negatively related to the accident severity. The results of this study can be used to assist the relevant maritime authorities in taking effective measures of preventing the occurrence of serious marine accidents.
Lancashire Fire and Rescue Service (LFRS), the subject of this evaluative research document employs 1400 people. 80% of employees are operational firefighters and officers whom operate across a range ...of duty systems and support functions, providing prevention, protection and emergency response to the communities of Lancashire.
The overarching purpose of this epidemiological study is to assess the prevalence of post-traumatic stress disorder (PTSD) amongst operational LFRS personnel and to analyse the effects upon those who may be suffering from it, whether brought about by a single traumatic event or by repeated exposure to traumatic occurrences over a period of time. A combination of primary and secondary research was carried out. Primary data was collated using two recognised clinical questionnaires and statistical analysis was conducted with the aid of the software package SPSS.
The findings and statistical analysis showed that out of the 100 people surveyed, 30% of respondents had signs of probable distress. Of this quota, 4% showed symptoms of PTSD. The study considers how an organisation can recognise and manage PTSD and provides recommendations to assist in better recognising and managing the associated risks.
Based upon the findings, the authors conclude that the level of PTSD within LFRS is slightly lower than those found in other studies undertaken within the Fire and Rescue Service sector. The paper provides recommendations for future studies and a series of actions for consideration by LFRS senior management to improve PTSD support services for employees.
Background: Lancashire Fire and Rescue Service (LFRS), the subject of this evaluative research document employs 1400 people. 80% of employees are operational firefighters and officers whom operate ...across a range of duty systems and support functions, providing prevention, protection and emergency response to the communities of Lancashire. Methods: The overarching purpose of this epidemiological study is to assess the prevalence of posttraumatic stress disorder (PTSD) amongst operational LFRS personnel and to analyse the effects upon those who may be suffering from it, whether brought about by a single traumatic event or by repeated exposure to traumatic occurrences over a period of time. A combination of primary and secondary research was carried out. Primary data was collated using two recognised clinical questionnaires and statistical analysis was conducted with the aid of the software package SPSS. Results: The findings and statistical analysis showed that out of the 100 people surveyed, 30% of respondents had signs of probable distress. Of this quota, 4% showed symptoms of PTSD. The study considers how an organisation can recognise and manage PTSD and provides recommendations to assist in better recognising and managing the associated risks. Conclusion: Based upon the findings, the authors conclude that the level of PTSD within LFRS is slightly lower than those found in other studies undertaken within the Fire and Rescue Service sector. The paper provides recommendations for future studies and a series of actions for consideration by LFRS senior management to improve PTSD support services for employees.
Reliability engineering is a well-defined field and systemic analysis is not new. Typically, the first raw-moment (MTTF) is all that is sought in applications of this method and a rule-of-thumb ...method achieves this algebraically without the need for calculus by assuming exponential distributions. However, there is no standard labelling or naming of the different block diagrams used, nor is there a standard list of solutions for low-order networks. In this paper different moments are compared, and the vector algebra approach is emphasised. A small amount of fine structure is evident in the moments, but broadly they are found to be equivalent for bulk system analysis. Analogy is made to statistical physics and a set of characteristic values is developed.
To identify and characterize the physically demanding tasks performed by SES personnel during storm damage work.
Thirty-six tasks identified as the most operationally important to storm damage work ...were included in a survey which was available to all SES volunteers. The survey aimed to identify the physical demand, operational importance, frequency, duration, principal actions and fitness components of each task.
Twelve tasks were identified as the most physically demanding. Of these, carrying sandbags, lifting sandbags and shoveling sand (with hands) rated highest. Covering roof damages with tarpaulin and erecting external weather proofing were ranked highest for operational importance. Box lifting (single-person) and erecting external weather proofing returned the highest mode values for frequency, whereas tasks involving handling sandbags returned the highest mean and median frequency values. Covering roof damages with tarpaulin was identified as the longest task. Bending, lifting, twisting and carrying were the most common actions identified for the physically demanding tasks. Muscular strength and muscular endurance were the primary fitness components identified for the twelve tasks.
SES personnel perform a variety of storm response tasks, many of which are physically demanding. All or most of the physically demanding tasks contain elements of bending, lifting, twisting and carrying, and call upon personnel’s muscular strength and muscular endurance capabilities.
This study first looks in depth into a model of support addressing low key maths skills in engineering courses. This new innovative 1-1 mathematics support system has been designed to provide ...essential key mathematics skills needed in a range of different subject areas across the different disciplines within the university. A robust 1-1 maths support system is put in place which can help weaker students first build their basic maths skills and then also help with the mathematics course material throughout the year thus leading to less students failing at the end of the year.
PDF
