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Tidal current technologies have the potential to provide highly predictable energy, since tides are driven by lunar cycles. However, before implementing such technologies on a large scale, their environmental performance should be assessed. In this study, a prospective life cycle assessment (LCA) was performed on a 12 MW tidal energy converter array of Minesto Deep Green 500 (DG500) prototypes, closely following the Environmental Product Declaration (EPD) standards, but including scenarios to cover various design possibilities. The global warming potential (GWP) of the prototype array was in the range of 18.4–26.3 gCO2-eq/kWhe. This is comparable with other renewable energy systems, such as wind power. Material production processes have the largest impact, but are largely offset by recycling at the end of life. Operation and maintenance processes, including the production of replacement parts, also provide major contributions to environmental impacts. Comparisons with other technologies are limited by the lack of a standardized way of performing LCA on offshore power generation technologies.

This paper summarizes the 76th LCA Discussion Forum end its main findings. Main issues when addressing emerging technologies identified were: the lack of primary data, the need for (shared) future background scenarios and (guidlines for) a common methodology. The following recommendations have been derived by the organizers: 1) Specific foreground inventories are always tailor-made, but consistency can be improved through lists of mandatory considerations. 2) Continue sharing (future) technology data and proxy processes, that can be readily replicated to new studies and assist in developing inventories. 3) Streamline and unify the process of including scenarios for background systems. New approaches may provide first important solutions to efficiently include consistent future scenarios in prospective LCA.

Surface engineering (SE) technologies are widely used in the energy and transportation sectors, protecting parts from wear and tear, and improving their energy efficiency. This leads to reduced greenhouse gas (GHG) emissions during the use phase, with increased emissions associated with the production of coating materials and the coating process that needs accounting for. Another significant issue lies in dissipative losses occurring throughout the component's life cycle, which are rarely assessed. With the expected increase in the use of SE and its importance in various applications, assessing the environmental impacts (and benefits) and the impact on the material losses (especially in terms of GHG emissions) is important to ensure those are minimized in the industry. Life cycle assessment (LCA) and material flow analysis (MFA) are the main industrial ecology tools used for such assessments. Those tools could be time consuming, especially in the data collection phase, and might hinder such studies in future development of innovative technologies. Thus, there is a need for an efficient approach to perform LCA, and possibly MFA, without compromising the confidence in the results.A literature review showed that those tools are seldom used for SE and are not designed for prospective large-scale assessments. Complementing them with integrated assessment models that follow consistent scenarios would allow for that. Furthermore, to simplify the LCA methodology, current approaches (e.g., streamlined and screening LCA) usually compromise simplicity with confidence in the results. Using uncertainty analysis to guide data collection would ensure reducing the efforts while focusing on the data leading to the most improvement in the results. The general objective of the thesis is to anticipate and assess the impacts of surface engineering on the environment and the material use at various scales of adoption. Three specific objectives were defined accordingly. The first is to evaluate the climatic environmental impacts of prospective large-scale adoption of novel surface engineering technologies. The second is to quantify the dissipative losses associated with surface engineering technologies and suggest circular economy strategies to reduce them. The final objective is to develop a methodology to steer the efforts of data collection in LCA using uncertainty analysis.First, LCA was linked with the MESSAGE integrated assessment model to assess the prospective environmental benefits (in terms of GHG emissions) and impacts of novel SE application. Applying innovative SE technologies to the energy sector has the potential of reducing annual CO2-eq emissions by 1.8 Gt in 2050 and 3.4 Gt in 2100 in an optimistic socio-economic pathway scenario. This corresponds to 7% and 8.5% annual reduction in the energy sector (compared to the baseline energy generation in MESSAGE SSP1) in 2050 and 2100, respectively. Besides, GHG emissions related to the coating processes are largely offset by the GHG savings of the energy conversion technologies where the innovative SE technologies are applied.Following that, a parametrized MFA was performed to quantify the dissipative losses from SE in the energy and transportation sectors in 2014 using the IEA ETP model. Results show that the coating process contributing most to the dissipative losses (up to 39%). High velocity oxy-fuel (HVOF) had the highest share of losses, with 15.5 ktonne of NiCrSi lost during the coating stage. Improving the deposition efficiency, recovering the unadhered powder and stripping the coating from the components at their end-of-life are key material efficiency strategies to reduce the material losses (up to 50%). Finally, a framework was proposed to reduce the time needed for data collection in LCA using uncertainty analysis. The framework requires modelling the uncertainty of the input parameters and propagating them through Monte Carlo simulations. Global sensitivity analysis is then used to rank the parameters based on their contribution to the output variability, and data collection is prioritized accordingly. A case study comparing additive manufacturing technologies was done to operationalize the framework, confirming the hypothesis of reducing the time to collect data, while highlighting some limitations of the framework.The main limitations of this research project are that surface engineering applications were not often documents, and thus the studies were limited to the energy and transportation sectors. Besides, due to the lack of data, many assumptions had to be done to model the inventories of coating needed for components. As more data becomes available, more representative models could be generated. For the suggested time efficient LCA framework, defining the uncertainty distribution for the screening data collection proved to be difficult, and better guidelines are needed there to ensure the validity of the results.While surface engineering can lead to reduced GHG emissions, especially in the energy sector, more work needs to be done to reduce the material dissipative losses. Future assessments could benefit from the proposed LCA framework to perform faster studies and drive innovation in the field.

Extending the lifetime of passive products, i.e., products that do not consume materials or energy during the use phase, by implementing product-service systems (PSS) has a potential to reduce the environmental impact while being an attractive and straightforward measure for companies to implement. This research assesses the viability of introducing PSS for passive products, by documenting five real product cases of prolonging the lifetime through repair or refurbishment and by quantifying, through life cycle assessment (LCA) and life cycle costing (LCC), the change in environmental and economic outcome. The environmental impact (measured as global warming potential over the life cycle) was reduced for all cases because extraction and production dominated the impact. This reduction was 45–72% for most cases and mainly influenced by the number of reuses and the relative environmental burden of the components whose lifetime was prolonged. The costs for the company (measured as LCC from the manufacturer’s perspective) decreased too by 8–37%. The main reason that costs reduced less than the environmental impact is that some costs have no equivalent in LCA, e.g., administration and labor costs for services. The decreases in both LCA and LCC results, as well as the willingness of the companies to implement the changes, demonstrate that this measure can be financially attractive for companies to implement and effectively contribute to a circular economy.

The goal of WITS Welding Intelligent Tutoring System is to provide a realistic and safe virtual reality environment to train electrical workers in performing standard alumino-thermal ground welding procedures on equipment in an electrical switching station yard. The WITS training system allows users to practice a variety of welding scenarios which satisfy company practices and provides help, feedback, and a performance evaluation. The Virtual Reality Interface, Expert System, Virtual Environment, and Monitoring modules of WITS are presented. This thesis focuses on the monitoring of human interactions in the WITS Welding Intelligent Tutoring System. The Monitoring module design includes welding task, manipulation, physics, scheduling, and weather agents. Implementation test results show the feasibility of this approach for monitoring the user's manual interactions in this training environment.

Mobile devices are increasingly permeating healthcare and are being regularly used by healthcare providers. We examined the prevalence and frequency of mobile device use, and perceptions around clinical and personal usage, among healthcare providers (attending physicians, residents, and nurses) in the Emergency Department (ED) of a large academic medical center in Lebanon. Half of the target population (N = 236) completed the cross-sectional electronic questionnaire. Mobile device usage for personal matters was uniform across all providers, with the highest usage reported by medical students (81.3%) and lowest by attendings (75.0%). Medical formulary/drug referencing applications were the most common application used by providers followed by disease diagnosis/management applications, 84.4% and 69.5% respectively. Most respondents agreed that mobile devices enabled better-coordinated care among providers and were beneficial to patient care. Most respondents also agreed that mobile device use assisted in quickly resolving personal issues and reduced their feeling of stress, yet the majority did not feel that personal usage improved performance at work. Study findings revealed that although healthcare providers value mobile devices’ positive impact on coordination of care, the reverse spillover effect of personal issues into the workplace enabled by mobile devices might have some negative impact on performance of staff at work.

Introduction: Pulmonary infections are not uncommon in patients with febrile neutropenia. Physicians have agreed to perform a chest X-ray (CXR) for all febrile neutropenic patients presenting with respiratory signs/symptoms. Nevertheless, they were divided into two groups when it came to asymptomatic febrile neutropenic patients (i.e. without respiratory signs/symptoms). A superior alternative to CXR is Computed Tomography (CT). CT, in comparison to CXR, was shown to have better sensitivity in detecting pulmonary foci. The aim of our study is to compare the diagnostic performance of CT and CXR in febrile neutropenic patients presenting to the emergency department, regardless of their clinical presentation. We are also interested in the predictors of pneumonia on chest imaging. Methodology: This is a retrospective cohort study conducted on febrile neutropenic adult cancer patients presenting to the emergency department of the American University of Beirut Medical Center. Results: 11.4% of 263 patients had pneumonia although 27.7% had respiratory signs/symptoms. 17.1% of those who were symptomatic and did a CXR were found to have pneumonia. 41.7% of those who were symptomatic and did a CT were found to have pneumonia. 30% had negative findings on CXR but pneumonia on CT. Conclusion: Patients with positive findings of pneumonia on chest imaging mainly had solid tumors, profound neutropenia, a higher CCI and a longer LOS. The presence of respiratory signs is the main predictor of positive pneumonia on chest imaging. CT is superior to CXR in detecting pulmonary foci in the population studied.

The role of urine studies in the detection of urinary tract infection (UTI) in febrile neutropenic patients with urinary symptoms (having a urinary catheter or having a positive urine analysis) is inarguable. However, the evidence is scarce regarding the indication for urine studies in asymptomatic (i.e., without urinary symptoms) patients with febrile neutropenia (FN) presenting to the emergency department (ED). The aim of this study is to evaluate the need for obtaining urine studies in asymptomatic febrile neutropenic patients. This was a retrospective cohort study conducted on adult cancer patients who presented to the ED with FN and had no urinary symptoms. We included all ED presentations of eligible patients between January 2013 and September 2018. Student's -test and Wilcoxon rank-sum test were used for continuous data, while Chi-square and Fisher's exact tests were used for categorical data. Participants were divided into two groups based on their urine culture (UC) results: negative and positive UCs. Two cut-offs were used for positive UC results: ≥10 cfu/mL and ≥10 cfu/mL. We included 284 patients in our study. The age of our patient population was 48.5±18.5 years. More than two-thirds (68.7%) of patients had severe neutropenia, while only 3.9% and 9.9% of the patients had positive UCs at ≥10 cfu/mL and ≥10 cfu/mL, respectively. UCs were expectedly positive in most patients with urinalysis (UA) abnormalities. However, 27.3% and 32.1% of patients with positive UCs at ≥10 cfu/mL and ≥10 cfu/mL respectively had a normal UA. In our study, the incidence of UTI in adult febrile neutropenic cancer patients who present to the ED without urinary symptoms is low. Consequently, routine urine testing may not be warranted in this population, as it adds unnecessary financial burdens on the patients and delays timely management.