Computational fluid dynamics (CFD) based approach to consequence assessment of accidental release of hydrocarbon during storage and transportation

This thesis investigated the risk of accidental release of hydrocarbons during transportation and storage. Transportation of hydrocarbons from an offshore platform to processing units through subsea pipelines involves risk of release due to pipeline leakage resulting from corrosion, plastic deformation caused by seabed shakedown or damaged by contact with drifting iceberg. The environmental impacts of hydrocarbon dispersion can be severe. Overall safety and economic concerns of pipeline leakage at subsea environment are immense. A large leak can be detected by employing conventional technology such as, radar, intelligent pigging or chemical tracer but in a remote location like subsea or arctic, a small chronic leak may be undetected for a period of time. In case of storage, an accidental release of hydrocarbon from the storage tank could lead pool fire; further it could escalate to domino effects. This chain of accidents may lead to extremely severe consequences. Analyzing past accident scenarios it is observed that more than half of the industrial domino accidents involved fire as a primary event, and some other factors for instance, wind speed and direction, fuel type and engulfment of the compound. In this thesis, a computational fluid dynamics (CFD) approach is taken to model the subsea pipeline leak and the pool fire from a storage tank. A commercial software package ANSYS FLUENT Workbench 15 is used to model the subsea pipeline leakage. The CFD simulation results of four different types of fluids showed that the static pressure and pressure gradient along the axial length of the pipeline have a sharp signature variation near the leak orifice at steady state condition. Transient simulation is performed to obtain the acoustic signature of the pipe near leak orifice. The power spectral density (PSD) of acoustic signal is strong near the leak orifice and it dissipates as the distance and orientation from the leak orifice increase. The high-pressure fluid flow generates more noise than the low-pressure fluid flow. In order to model the pool fire from the storage tank, ANSYS CFX Workbench 14 is used. The CFD results show that the wind speed has significant contribution on the behavior of pool fire and its domino effects. The radiation contours are also obtained from CFD post processing, which can be applied for risk analysis. The outcome of this study will be helpful for better understanding of the domino effects of pool fire in complex geometrical settings of process industries. The attempt to reduce and prevent risks is discussed based on the results obtained from the numerical simulations of the numerical models.

A deep learning-based approach for 3D people tracking

Questa tesi si occupa dell’estensione di un framework software finalizzato all'individuazione e al tracciamento di persone in una scena ripresa da telecamera stereoscopica. In primo luogo è rimossa la necessità di una calibrazione manuale offline del sistema sfruttando algoritmi che consentono di individuare, a partire da un fotogramma acquisito dalla camera, il piano su cui i soggetti tracciati si muovono. Inoltre, è introdotto un modulo software basato su deep learning con lo scopo di migliorare la precisione del tracciamento. Questo componente, che è in grado di individuare le teste presenti in un fotogramma, consente ridurre i dati analizzati al solo intorno della posizione effettiva di una persona, escludendo oggetti che l’algoritmo di tracciamento sarebbe portato a individuare come persone.

Distributed Learning: An Agent-Based Approach to Data-Mining

Peer reviewed

Promoting faculty professionalism: a case-based approach.

INTRODUCTION: Professionalism is a key attribute for health professionals. Yet, it is unknown how much faculty development is directed toward skills and behaviours of faculty professionalism. Faculty professionalism includes boundaries in teacher-student relationships, self-reflection, assuring one's own fitness for duty, and maintaining confidentiality when appropriate. METHODS: For five years, we have incorporated faculty professionalism as a routine agenda item for the monthly Physician Assistant Programme faculty meetings, allowing faculty members to introduce issues they are comfortable sharing or have questions about. We also have case discussions of faculty professionalism within faculty meetings every three months. RESULTS: Faculty professionalism is important in the daily work lives of faculty members and including this as part of routine agendas verifies its importance. A faculty survey showed that a majority look forward to the quarterly faculty professionalism case discussions. These have included attempted influence in the admissions process, student/faculty social boundaries, civic professionalism, students requesting medical advice, and self-disclosure. CONCLUSION: A preventive approach works better than a reactionary approach to faculty missteps in professionalism. Routine discussion of faculty professionalism normalizes the topic and is helpful to both new and experienced faculty members. We recommend incorporation of faculty professionalism as a regular agenda item in faculty meetings.

Constraint-force-based approach of modelling compliant mechanisms: principle and application

Numerous works have been conducted on modelling basic compliant elements such as wire beams, and closed-form analytical models of most basic compliant elements have been well developed. However, the modelling of complex compliant mechanisms is still a challenging work. This paper proposes a constraint-force-based (CFB) modelling approach to model compliant mechanisms with a particular emphasis on modelling complex compliant mechanisms. The proposed CFB modelling approach can be regarded as an improved free-body- diagram (FBD) based modelling approach, and can be extended to a development of the screw-theory-based design approach. A compliant mechanism can be decomposed into rigid stages and compliant modules. A compliant module can offer elastic forces due to its deformation. Such elastic forces are regarded as variable constraint forces in the CFB modelling approach. Additionally, the CFB modelling approach defines external forces applied on a compliant mechanism as constant constraint forces. If a compliant mechanism is at static equilibrium, all the rigid stages are also at static equilibrium under the influence of the variable and constant constraint forces. Therefore, the constraint force equilibrium equations for all the rigid stages can be obtained, and the analytical model of the compliant mechanism can be derived based on the constraint force equilibrium equations. The CFB modelling approach can model a compliant mechanism linearly and nonlinearly, can obtain displacements of any points of the rigid stages, and allows external forces to be exerted on any positions of the rigid stages. Compared with the FBD based modelling approach, the CFB modelling approach does not need to identify the possible deformed configuration of a complex compliant mechanism to obtain the geometric compatibility conditions and the force equilibrium equations. Additionally, the mathematical expressions in the CFB approach have an easily understood physical meaning. Using the CFB modelling approach, the variable constraint forces of three compliant modules, a wire beam, a four-beam compliant module and an eight-beam compliant module, have been derived in this paper. Based on these variable constraint forces, the linear and non-linear models of a decoupled XYZ compliant parallel mechanism are derived, and verified by FEA simulations and experimental tests.

An Evidence-Based Approach to Access Reform (Working Paper 22)

In August 2000, the federal government began an internal review of the Access to Information Act (ATIA). The ATIA gives Canadians a qualified right of access to records held by federal institutions. Decisions about reform should be based on good evidence about the operation of the Act and the likely impact of proposed reforms. This paper describes how data on ATIA operations is collected by federal institutions and provides a guide to academic researchers interested in conducting empirical research on the operation of the law. It constructs a small dataset that describes the processing of a sample of 663 requests received in 1999, and uses this dataset to illustrate the potential of an evidence-based approach to ATIA reform. The dataset can be downloaded from http://evidence.foilaw.net. The project was supported by a $4,800 grant from the Principal’s Development Fund of Queen’s University awarded in May 2001. Comments should be sent to the principal investigator, Alasdair Roberts, at roberts@policystudies.ca.

A Knowledge Management Process-Based Approach to Support Corporate Crisis Management

In the crisis-prone and complex contemporary business environment, modern organisations and their supply chains, large and small, are challenged by crises more than ever. Knowledge management has been acknowledged as an important discipline able to support the management of complexity in times of crisis. However, the role of effective knowledge retrieval and sharing in the process of crisis prevention, management and survival has been relatively underexplored. In this paper, it is argued that organisational crises create additional challenges for knowledge management, mainly because complex, polymorphic and both structured and unstructured knowledge must be efficiently harnessed, processed and disseminated to the appropriate internal and external supply chain actors, under specific time constraints. In this perspective, a process-based approach is proposed to address the knowledge management needs of organisations during a crisis and to help management in establishing the necessary risk avoidance and recovery mechanisms. Finally, the proposed methodological approach is applied in a knowledge- intensive Greek small and medium enterprise from the pharmaceutical industry, producing empirical results, insights on knowledge pathologies during crises and relevant evaluations.

Towards a knowledge-based approach for effective decision-making in railway safety

Purpose – This paper aims to contribute towards understanding how safety knowledge can be elicited from railway experts for the purposes of supporting effective decision-making. Design/methodology/approach – A consortium of safety experts from across the British railway industry is formed. Collaborative modelling of the knowledge domain is used as an approach to the elicitation of safety knowledge from experts. From this, a series of knowledge models is derived to inform decision-making. This is achieved by using Bayesian networks as a knowledge modelling scheme, underpinning a Safety Prognosis tool to serve meaningful prognostics information and visualise such information to predict safety violations. Findings – Collaborative modelling of safety-critical knowledge is a valid approach to knowledge elicitation and its sharing across the railway industry. This approach overcomes some of the key limitations of existing approaches to knowledge elicitation. Such models become an effective tool for prediction of safety cases by using railway data. This is demonstrated using passenger–train interaction safety data. Practical implications – This study contributes to practice in two main directions: by documenting an effective approach to knowledge elicitation and knowledge sharing, while also helping the transport industry to understand safety. Social implications – By supporting the railway industry in their efforts to understand safety, this research has the potential to benefit railway passengers, staff and communities in general, which is a priority for the transport sector. Originality/value – This research applies a knowledge elicitation approach to understanding safety based on collaborative modelling, which is a novel approach in the context of transport.

Random Forest Based Approach for Concept-Drift Handling

Algorithms for concept drift handling are important for various applications including video analysis and smart grids. In this paper we present decision tree ensemble classication method based on the Random Forest algorithm for concept drift. The weighted majority voting ensemble aggregation rule is employed based on the ideas of Accuracy Weighted Ensemble (AWE) method. Base learner weight in our case is computed for each sample evaluation using base learners accuracy and intrinsic proximity measure of Random Forest. Our algorithm exploits both temporal weighting of samples and ensemble pruning as a forgetting strategy. We present results of empirical comparison of our method with îriginal random forest with incorporated replace-the-looser forgetting andother state-of-the-art concept-drift classiers like AWE2.

Measuring children’s experience of their right to participate in school and community: a rights-based approach

This paper discusses the development of a children’s rights-based measure of participation and the findings from its use in a survey of 10 to 11 year old children (n= 3773). The measure, which was developed in collaboration with a group of children, had a high reliability (Cronbach’s alpha = .89). Findings suggest that children’s positive experience of their participation rights is higher in school than in community, and higher for girls compared to boys. It is argued that involving children in the ‘measurement’ of their own lives has the potential to generate more authentic data on children’s lived experiences.

A novel hybrid swarm based approach for curriculum based course timetabling problem

This work applies a hybrid approach in solving the university curriculum-based course timetabling problem as presented as part of the 2nd International Timetabling Competition 2007 (ITC2007). The core of the hybrid approach is based on an artificial bee colony algorithm. Past methods have applied artificial bee colony algorithms to university timetabling problems with high degrees of success. Nevertheless, there exist inefficiencies in the associated search abilities in term of exploration and exploitation. To improve the search abilities, this work introduces a hybrid approach entitled nelder-mead great deluge artificial bee colony algorithm (NMGD-ABC) where it combined additional positive elements of particle swarm optimization and great deluge algorithm. In addition, nelder-mead local search is incorporated into the great deluge algorithm to further enhance the performance of the resulting method. The proposed method is tested on curriculum-based course timetabling as presented in the ITC2007. Experimental results reveal that the proposed method is capable of producing competitive results as compared with the other approaches described in literature

An Action Research Study Engaging in the Use of Storyboarding as Research-based Approach to Teaching to Identify Issues Faced when Working with People with Dementia from Minority Ethnic Communities

The common view that research informs teaching assumes a linear approach whereby teaching is considered an output of research. This paper reports the findings of an action research project that identified the issues and challenges faced by those working across health and social care when working with people with dementia from minority ethnic communities. It explored the research-teaching nexus by using an approach to teaching that was research-based as opposed to research-led. A storyboarding technique was used which involved identifying and dissecting real life experiences for discussion. The realisation that each story was unique to the individual demonstrated the benefits and importance of education and training for applying a person-centred approach to dementia care. This project also revealed the benefits of actively engaging course participants with research moving them from being recipients of research, to research- active. Such a process not only encouraged their intrinsic motivations but, also, critical thinking and reflective practice to support deep learning. Such findings demonstrate the benefits of linking teaching with research.

A DST-based Approach for Construction Project Risk Analysis

Despite its huge potential in risk analysis, the Dempster–Shafer Theory of Evidence (DST) has not received enough attention in construction management. This paper presents a DST-based approach for structuring personal experience and professional judgment when assessing construction project risk. DST was innovatively used to tackle the problem of lacking sufficient information through enabling analysts to provide incomplete assessments. Risk cost is used as a common scale for measuring risk impact on the various project objectives, and the Evidential Reasoning algorithm is suggested as a novel alternative for aggregating individual assessments. A spreadsheet-based decision support system (DSS) was devised to facilitate the proposed approach. Four case studies were conducted to examine the approach's viability. Senior managers in four British construction companies tried the DSS and gave very promising feedback. The paper concludes that the proposed methodology may contribute to bridging the gap between theory and practice of construction risk assessment.

Exploring Perceptual Matters: A Textile-Based Approach

This research takes a practice-based approach to exploring perceptual matters that often go unnoticed in the context of everyday lived experience. My approach focuses on the experiential possibilities of knowledge emerging through artistic enquiry, and uses a variety of modes (like textiles, sound, physical computing, programming, video and text) to be conducted and communicated. It examines scholarship in line with the ecological theory of perception, and is particularly informed by neurobiological research on sensory integration as well as by cultural theories that examine the role of sensory appreciation in perception. Different processes contributing to our perceptual experience are examined through the development of a touch-sensitive, sound-generating rug and its application in an experimental context. Participants’ interaction with the rug and its sonic output allows an insight into how they make sense of multisensory information via observation of how they physically respond to it. In creating possibilities for observing the two ends of the perceptual process (sensory input and behavioural output), the rug provides a platform for the study of what is intangible to the observer (perceptual activity) through what can actually be observed (physical activity). My analysis focuses on video recordings of the experimental process and data reports obtained from the software used for the sound generating performance of the rug. Its findings suggest that attentional focus, active exploration, and past experience actively affect the ability to integrate multisensory information and are crucial parameters for the formation of a meaningful percept upon which to act. Although relational to the set experimental conditions and the specificities of the experimental group, these findings are in resonance with current cross-disciplinary discourse on perception, and indicate that art research can be incorporated into the wider arena of neurophysiological and behavioural research to expand its span of resources and methods.

The Effects of a Group-Based Approach to Parent-Mediated Early Behavioral Intervention for Very Young Children with or At-Risk for Autism

Thesis (Ph.D.)--University of Washington, 2016-08