Search results for " Reliability."
showing 10 items of 551 documents
Stress-strain models for normal and high strength confined concrete: Test and comparison of literature models reliability in reproducing experimental…
2017
SUMMARY: The adoption of proper constitutive laws for confined concrete is basic for seismic assessment of new and existing reinforced concrete civil structures. The deformation capacity of reinforced concrete (RC) columns subjected to axially centred and eccentric loads depends on the effectiveness confinement action. A proper assignment of the stressstrainlaws for concrete allows obtaining an adequate definition of the ductility of the crosssections and correctly identifying mechanical nonlinearities in computational models.Several studies concerning the behaviour of confined concrete have been carried out, highlighting the role of different geometrical and mechanical parameters to the ov…
Improving Reliability of Road Safety Estimates Based on High Correlated Accident Counts
2007
Calibrating a safety performance function (SPF) with many years of accident data creates a temporal correlation that traditional model calibration procedures cannot deal with. It is well known that generalized estimating equations (GEE) models are able to incorporate trends into accident data and thus overcome difficulties in accounting for correlation; the usual application of GEEs to safety analysis uses robust (or sandwich) estimates of regression coefficients under the independence hypothesis for the working correlation matrix. This practice is justified by the robustness of the GEE procedure against misspecification of the response correlation structure. Nevertheless, with this method…
A root cause analysis method for preventing erratic behavior in software development: PEBA
2019
Measures taken to prevent faults from being introduced or going undetected can secure development of highly reliable software systems. One such measure is analyzing root causes of recurring faults and preventing them from appearing again. Previous methods developed for this purpose have been reactive in nature and relied heavily on fault reporting mechanisms of ogranizations. Additionally, previous efforts lack a defined mechanism for innovating corrective actions. In this study, we strive to complement the existing methods by introducing a proactive and qualitative method that does not rely on fault data. During the course of the research, in addition to an extensive literature search, an …
Language-Integrated Privacy-Aware Distributed Queries
2019
Distributed query processing is an effective means for processing large amounts of data. To abstract from the technicalities of distributed systems, algorithms for operator placement automatically distribute sequential data queries over the available processing units. However, current algorithms for operator placement focus on performance and ignore privacy concerns that arise when handling sensitive data. We present a new methodology for privacy-aware operator placement that both prevents leakage of sensitive information and improves performance. Crucially, our approach is based on an information-flow type system for data queries to reason about the sensitivity of query subcomputations. Ou…
The Safety Culture Enactment Questionnaire (SCEQ): Theoretical model and empirical validation
2015
This paper presents the Safety Culture Enactment Questionnaire (SCEQ), designed to assess the degree to which safety is an enacted value in the day-to-day running of nuclear power plants (NPPs). The SCEQ is based on a theoretical safety culture model that is manifested in three fundamental components of the functioning and operation of any organization: strategic decisions, human resources practices, and daily activities and behaviors. The extent to which the importance of safety is enacted in each of these three components provides information about the pervasiveness of the safety culture in the NPP. To validate the SCEQ and the model on which it is based, two separate studies were carried…
Design of a safety training package for migrant workers in the construction industry
2021
Abstract The construction sector is known as a high-risk sector with many safety challenges. It is also characterised by a large number of migrant workers and these workers report higher accident rates than native workers. This paper presents the design of the CSTP (Construction Safety Training Programme). The CSTP is a theory-based training program aimed at improving safety behaviours in construction sites acknowledging the particular challenges migrant workers face. Based on second and third generational models of training, we developed a training program that addresses the challenges faced by migrant workers in the construction industry, namely language and cultural barriers, times press…
Human Reliability Analysis to support operational planning of an experimental facility
2015
This paper reports the results obtained by using different techniques of Human Reliability Analysis (HRA) to identify potential operator errors at the SPES (Selective Production of Exotic Species) facility, a second generation Isotope Separation On Line (ISOL) plant for advanced nuclear physic applications. The paper presents scoping-level HRA applications, with the main goal to evaluate the applicability of HRA techniques for the specific domain. In particular, two aspects challenge a standard HRA. First, the facility is under construction so that a number of aspects related to its operation (e.g. procedures and operator interfaces) are still under definition. Second, the context of operat…
Ex vivo measurement reliability using two different cbct scanners for orthodontic purposes
2012
Background There are many cone beam computed tomography (CBCT) scanners available on the market: detector technology, algorithm precision, and scanner settings influence image quality. The aim of this study was to compare the accuracy of linear measurements made on images of the same sample obtained using two different CBCT scanners. Methods Twenty-eight linear measurements between orthodontic anatomical landmarks that were marked with gutta-percha points on a fresh sacrificed lamb head were taken three times. The head was scanned with two CBCT scanners using different scanning parameters. Digital Imaging and Communications in Medicine (DICOM) images were reconstructed and the same measurem…
Attribute based access control scheme with controlled access delegation for collaborative E-health environments
2017
Abstract Modern electronic healthcare (e-health) settings constitute collaborative environments with complex access requirements. Thus, there is a need for sophisticated fine-grained access control mechanisms to cater these access demands and thereby experience the full potential of e-health systems. In order to realize a flexible access control scheme, integrating access delegation is of paramount importance. However, access delegation has to be enforced in a controlled manner so that it will not jeopardize the security of the system. In this paper, we addressed this issue through proposing an attribute based access control scheme integrated with controlled access delegation capabilities. …
Strategies to exiting the COVID-19 lockdown for workplace and school: A scoping review
2021
Highlights • Epidemiological conditions should be monitored and enforced. • COVID-19 must be under control below thresholds of safeguards. • Testing, contact tracing, and isolation strategies are essential components to ease the lockdown. • The maintenance of social distancing measures is an overarching mitigation strategy. • The benefit gained from the implementation of social distancing was evident.