A comparison of data-driven and model-based approaches to quantifying railway risk

This paper presents some of the results of a project sponsored by the UK Railway Safety and Standards Board (RSSB). An earlier statistical evaluation of a previous version of the RSSB Safety Risk Model (SRM), a combined Fault/Event Tree, conducted by Prof Andrew Evans had concluded that the model was unduly pessimistic. We have constructed a hypothesis test based on the relative likelihood techniques using the most recent version of the SRM as the null hypothesis. The results support the SRM being consistent with the historical data. Two significant differences between these two studies are the statistical methods employed to support the analysis and the removal of certain significant conservative assumptions from updating the versions of the SRM. The paper discusses the demands that different model purposes place on these models, and explores the question of whether or not it is meaningful to compare their outputs. The use of expected fatalities as a metric for expressing risk in both models is questioned because of the heavy-tailed form of the distribution for fatality numbers given a fatal accident

A Real-Time Remote IDS Testbed for Connected Vehicles

Connected vehicles are becoming commonplace. A constant connection between vehicles and a central server enables new features and services. This added connectivity raises the likelihood of exposure to attackers and risks unauthorized access. A possible countermeasure to this issue are intrusion detection systems (IDS), which aim at detecting these intrusions during or after their occurrence. The problem with IDS is the large variety of possible approaches with no sensible option for comparing them. Our contribution to this problem comprises the conceptualization and implementation of a testbed for an automotive real-world scenario. That amounts to a server-side IDS detecting intrusions into vehicles remotely. To verify the validity of our approach, we evaluate the testbed from multiple perspectives, including its fitness for purpose and the quality of the data it generates. Our evaluation shows that the testbed makes the effective assessment of various IDS possible. It solves multiple problems of existing approaches, including class imbalance. Additionally, it enables reproducibility and generating data of varying detection difficulties. This allows for comprehensive evaluation of real-time, remote IDS.Comment: Peer-reviewed version accepted for publication in the proceedings of the 34th ACM/SIGAPP Symposium On Applied Computing (SAC'19

A Flight Investigation of the STOL Characteristics of an Augmented Jet Flap STOL Research Aircraft

The flight test program objectives are: (1) To determine the in-flight aerodynamic, performance, and handling qualities of a jet STOL aircraft incorporating the augmented jet flap concept; (2) to compare the results obtained in flight with characteristics predicted from wind tunnel and simulator test results; (3) to contribute to the development of criteria for design and operation of jet STOL transport aircraft; and (4) to provide a jet STOL transport aircraft for STOL systems research and development. Results obtained during the first 8 months of proof-of-concept flight testing of the aircraft in STOL configurations are reported. Included are a brief description of the aircraft, fan-jet engines, and systems; a discussion of the aerodynamic, stability and control, and STOL performance; and pilot opinion of the handling qualities and operational characteristics

Analyzing the effects of Video Games on Social Anxiety and Communication

Those with high levels of social anxiety can struggle with their communication skills, and confidence in communication. By using a virtual platform such as Zoom to communicate with others, individuals with social anxiety have shown decreased levels of anxiety, even noting that they prefer the virtual platform over face-to-face encounters (Yen et al., 2012). Video games can increase this level of anonymity that could be felt through zoom, by removing the ability to see the other individual’s face. This gives video games the opportunity to decrease anxiety levels while still requiring a degree of communication. Participants will be randomly sorted into pairs within one of two groups; competitive and cooperative to test if the type of game can affect communication levels. The Liebowitz Social Anxiety Scale will be used in order to determine the individual’s social anxiety level of participants prior to testing (Heimburg, et al., 1999). It is expected that the individuals paired in the cooperative group will have a greater increase in confidence and ability to communicate than those who are paired in the competitive group. Overall it is hypothesized that the results will reflect that those with higher levels of social anxiety as determined by the Liebowitz Social Anxiety scale will have a more significant drop in anxiety in comparison to those who have a lower score in social anxiety

Chinese politics and foreign powers

title continued Syllabus on recent Chinese politics and diplomacy, 46 pageshttps://digitalrepository.trincoll.edu/moore/1051/thumbnail.jp

The Written Acknowledgement: Its Effect on the Operation of the Statute of Limitations

B owes A $100. Will an acknowledgment in writing that the debt is owed, by a statement such as I owe you$100 , containing no express promise to pay, toll the statute of limitations? If so, is the time at which the acknowledgment is made, i. e., before or after the statute has once run, significant? Williston states that the unqualified acknowledgment in writing of a present obligation to another, unaccompanied by any evidence showing a determination not to pay, contains the tacit or implied expression of a promise to pay; that a promise to pay is by implication of fact a part of the acknowledgment and hence operates to toll the statute. This view, supported by case authority and accepted by the Restatement of Contracts, appears to be the general rule. Williston points out that it is an artificial inference of fact, but that the preponderance of decisions has so held even though it is not made in respect to acknowledgments of debt in related situations. There are a few jurisdictions which disregard the need of a promise, express or implied, and follow the rule popular in Lord Mansfield\u27s day, i. e., that the acknowledgment, though implying no promise, is sufficient to toll the statute

The energy and thermal performance of UK modular residential buildings

This research concerns the in-use performance of light-gauge steel modular construction used for residential purposes. The aim was to investigate ways to reduce the in-use energy consumption of new buildings, while ensuring thermal comfort. Data were collected from two case study buildings in the UK, one in Loughborough and the other in London, using a variety of methods including building measurement, building monitoring, inspections, and a detailed review of the construction documentation. The case study buildings were monitored using EnOcean enabled wireless sensor networks and standalone temperature sensors. Monitoring data included electricity consumption in individual rooms, often by end use, space heating use, internal temperature and relative humidity, and external temperature. Building measurements included blower door tests to measure fabric air leakage rates, infrared thermal imaging to identify fabric defects and weaknesses, and ventilation system flowrate measurements. Inspections and the review of documentation allowed problems with design, manufacture and construction to be identified. A particular concern for thermally lightweight construction is the risk of overheating, therefore overheating analyses were undertaken. The research identified weaknesses in the design, construction and operation of the case study buildings resulting in increased energy use and poor thermal comfort, particularly overheating. The modular construction studied requires specific design changes to improve the fabric and building services, in order to reduce energy use. There are also specific recommendations for quality control on site to ensure critical stages are correctly completed, such as installing rigid insulation. There are also more general recommendations for how a company operates because this can influence performance; there ought to be greater attention to holistic design and greater collaboration with suppliers and contractors to determine robust solutions. Overheating was a problem in the London case study, and more research is required to understand the scale of the problem. Avoidance of overheating must be a focus in the design of new buildings. The findings suggest that once the problems with the design and quality control on site are rectified, offsite modular construction can be used to consistently and reliably provide low energy homes

Potential economic impacts from improving breastfeeding rates in the UK

This article has been made available through the Brunel Open Access Publishing Fund.RATIONALE: Studies suggest that increased breastfeeding rates can provide substantial financial savings, but the scale of such savings in the UK is not known. OBJECTIVE: To calculate potential cost savings attributable to increases in breastfeeding rates from the National Health Service perspective. DESIGN AND SETTINGS: Cost savings focussed on where evidence of health benefit is strongest: reductions in gastrointestinal and lower respiratory tract infections, acute otitis media in infants, necrotising enterocolitis in preterm babies and breast cancer (BC) in women. Savings were estimated using a seven-step framework in which an incidence-based disease model determined the number of cases that could have been avoided if breastfeeding rates were increased. Point estimates of cost savings were subject to a deterministic sensitivity analysis. RESULTS: Treating the four acute diseases in children costs the UK at least £89 million annually. The 2009-2010 value of lifetime costs of treating maternal BC is estimated at £959 million. Supporting mothers who are exclusively breast feeding at 1 week to continue breast feeding until 4 months can be expected to reduce the incidence of three childhood infectious diseases and save at least £11 million annually. Doubling the proportion of mothers currently breast feeding for 7-18 months in their lifetime is likely to reduce the incidence of maternal BC and save at least £31 million at 2009-2010 value. CONCLUSIONS: The economic impact of low breastfeeding rates is substantial. Investing in services that support women who want to breast feed for longer is potentially cost saving

Performance of medium-rise, thermally lightweight apartment buildings during a heat wave

There is growing evidence that medium rise, thermally lightweight, well-insulated, naturally ventilated, single apartment blocks are at risk of overheating especially when sited in the SE of England. This paper reports the thermal comfort and heat stress conditions recorded in 15 apartments located in North London on the outer fringes of the urban heat island. The apartments were built using off site, light gauge steel prefabrication methods. Bedrooms on floors one and two and on floors seven to eleven were monitored for 22 days during July and August 2013, a period that included a heat wave, which precipitated a level 3 heat wave alert. The risk of overheating was assessed using the static criteria in CIBSE Guide A and the three CIBSE TM52 adaptive thermal comfort criteria. Heat stress levels in one room were assessed using the Humidex and Heat Index metrics. The bedrooms on floors one and two did not overheat whereas all the apartments on the upper floors failed both the static and the adaptive criteria producing conditions that would lead to heat stress. The results strongly suggest that the design, ventilation and servicing strategy, combined with the inherent fragility of thermally lightweight and well insulated construction, is inappropriate in some areas of the UK and may even be dangerous in hot summers. The findings have significance for construction companies, landlords and social housing providers and those concerned with construction guidelines and the building regulations