Quantitative imaging in radiation oncology

Artificially intelligent eyes, built on machine and deep learning technologies, can empower our capability of analysing patients’ images. By revealing information invisible at our eyes, we can build decision aids that help our clinicians to provide more effective treatment, while reducing side effects. The power of these decision aids is to be based on patient tumour biologically unique properties, referred to as biomarkers. To fully translate this technology into the clinic we need to overcome barriers related to the reliability of image-derived biomarkers, trustiness in AI algorithms and privacy-related issues that hamper the validation of the biomarkers. This thesis developed methodologies to solve the presented issues, defining a road map for the responsible usage of quantitative imaging into the clinic as decision support system for better patient care

Development and application in clinical practice of Computer-aided Diagnosis systems for the early detection of lung cancer

Lung cancer is the main cause of cancer-related deaths both in Europe and United States, because often it is diagnosed at late stages of the disease, when the survival rate is very low if compared to first asymptomatic stage. Lung cancer screening using annual low-dose Computed Tomography (CT) reduces lung cancer 5-year mortality by about 20% in comparison to annual screening with chest radiography. However, the detection of pulmonary nodules in low-dose chest CT scans is a very difficult task for radiologists, because of the large number (300/500) of slices to be analyzed. In order to support radiologists, researchers have developed Computer aided Detection (CAD) algorithms for the automated detection of pulmonary nodules in chest CT scans. Despite proved benefits of those systems on the radiologists detection sensitivity, the usage of CADs in clinical practice has not spread yet. The main objective of this thesis is to investigate and tackle the issues underlying this inconsistency. In particular, in Chapter 2 we introduce M5L, a fully automated Web and Cloud-based CAD for the automated detection of pulmonary nodules in chest CT scans. This system introduces a new paradigm in clinical practice, by making available CAD systems without requiring to radiologists any additional software and hardware installation. The proposed solution provides an innovative cost-effective approach for clinical structures. In Chapter 3 we present our international challenge aiming at a large-scale validation of state-of-the-art CAD systems. We also investigate and prove how the combination of different CAD systems reaches performances much higher than any best stand-alone system developed so far. Our results open the possibility to introduce in clinical practice very high-performing CAD systems, which miss a tiny fraction of clinically relevant nodules. Finally, we tested the performance of M5L on clinical data-sets. In chapter 4 we present the results of its clinical validation, which prove the positive impact of CAD as second reader in the diagnosis of pulmonary metastases on oncological patients with extra-thoracic cancers. The proposed approaches have the potential to exploit at best the features of different algorithms, developed independently, for any possible clinical application, setting a collaborative environment for algorithm comparison, combination, clinical validation and, if all of the above were successful, clinical practice

Thermoeconomic Analysis of Csp Air-Steam Mixed Cycles with Low Water Consumption

Abstract Starting from a state of the art of CSP plants and the undergoing research in hybridization of Gas Turbine plants, the paper investigates alternative plant configurations particularly regarding the integration of CSP technology with mixed cycles because of their low water consumption and the possible use of current CSP components, assessed and compared with a through-life thermo-economic analysis

Gas turbine combined cycle start-up and stress evaluation: A simplified dynamic approach

The main topic of this work is the development and validation of a simplified approach for the dynamic analysis of a Gas Turbine Combined Cycle (GTCC), with a particular focus on start-up procedure and associated mechanical stresses on the steam turbine (ST). The currently deregulated energy market led GTCC to undergo frequent startups, a condition often not considered during plant design. Moreover, the time required for the start-up is crucial under an economical viewpoint, though it is constrained by mechanical stresses imposed to thick components by thermal gradients. The framework proposed in this work aims to improve the accessibility to simulation software by applying commonly used office suite \ue2\u80\u93 Microsoft Excel/Visual Basic \ue2\u80\u93 with acceptable reduction in accuracy. Simplicity of model allow fast computation and its exploitation can be pursued by non-qualified plant operators. The obtained tool can be than adopted to support decision process during plant operations. The developed tool has been validated for a hot start-up against field measurements supplied by Tirreno Power S.p.A. Italy. Data are recorded through control and monitoring sensors of a 390 MW multi-shaft combined cycle based on the GT AEN94.3 A4 frame, but the results can be easily generalized to other layouts. Simulation result and stress evaluations around the steam turbine (ST) rotor show good agreement with experimental data

Analysis of the Barriers to the Uptake of R&D Results in the Power Sector

Power grid vulnerabilities are European wide problems, they cannot be solved individually but require a coordinated European effort. GRID aims at establishing a roadmap for collaborative R&D on power grid security, also based on exchange of information about national, regional and European research projects. Collaborative research programmes might benefit from a mutual exchange of approaches, experiences, and results. However, cross fertilisation may be hampered by existing barriers of an institutional, socio-economic and technical nature. This report investigates barriers to exploitation of national research results in a European context.JRC.G.6-Sensors, radar technologies and cybersecurit

Real-time state of charge estimation in thermal storage vessels applied to a smart polygeneration grid

In thermal grids and district heating, thermal storage devices play an important role to manage energy demand. Additionally, in smart polygeneration grids, thermal energy storage devices are essential to achieve high flexibility in energy demand management at relatively low cost. In this scenario, accurate evaluation of state of charge of storage vessels based on available measurements is critical. The aim of this paper is to develop and compare three different models for state of charge estimation in stratified water tanks (discrete temperature measurements) and the related application in an experimental polygeneration grid with a real-time management tool. The first model is based on the empirical calculation of the state of charge considering the thermal power difference between generation and consumption, and afterwards correction based on measured temperatures. The second model is a mathematical approach considering a pre-defined temperature shape fitted with experimental data. The latter model is based on a 1-D physical approach using a multi-nodal method forced on the basis of the measured temperatures. The models were compared considering an experimental test performed in the polygeneration laboratory by the Thermochemical Power Group (TPG). As a result of the comparative analysis, the first model was selected for applications in complex polygeneration grids, due to its good compromise between accuracy and computational effort. Several tests were carried out to demonstrate the performance of the empirical approach selected for the thermal storage model and the economic benefit related to the utilization of this vessel. The experimental plant, constituted by two different prime movers (a 100 kW microturbine and a 20 kW internal combustion engine) and a thermal storage tank, was able to demonstrate the performance of a real-time management tool. For this reason, special attention was devoted to the variable cost comparisons. The novelty of this work lies in the development of the real-time management tool coupled with a thermal storage model by considering the simplified modelling approach. This is an essential requisite for complex polygeneration grids including hundreds or thousands of prime movers and thermal storage devices. Additionally, it is important to state that in such cases the required real-time performance could be difficult to obtain. The results, produced with the innovative and flexible experimental rig, demonstrate the positive impact of thermal storage as well as the effective management performance of this quite simple dispatching approach. Another important novel aspect regards this experimental assessment considering both specific 3-h tests andextended conditions typical of a possible real application

AMBIENT TEMPERATURE IMPACT ON MICRO GAS TURBINES: EXPERIMENTAL CHARACTERIZATION

In the panorama of gas turbines for energy production, a great relevance is given to performance impact of the ambient conditions. Under the influence of ambient temperature, humidity and other factors, the engine performance is subject to consistent variations. This is true for large power plants as well as small engines. In Combined Cycle configuration, variation in performance are mitigated by the HRSG and the bottoming steam cycle. In a small scale system, such as a micro gas turbine, the influence on the electric and thermal power productions is strong as well, and is not mitigated by a bottoming cycle. This work focuses on the Turbec T100 micro gas turbine and its performance through a series of operations with different ambient temperatures. The goal is to characterize the engine performance deriving simple correlations for the influence of ambient temperature on performance, at different electrical loads. The newly obtained experimental data are compared with previous performance curves on a modified machine, to capture the differences due to hardware degradation in time. An active management of the compressor inlet temperature may be developed in the future, basing on the analysis reported here

sustainable district development a case of thermoeconomic optimization of an energy hub

Sustainable distric development requires innovative energy use solutions. The aim of this paper is to illustrate the operation of a real energy hub that can satisfy both thermal and electrical demands of a generic user. In particular, a specific case study developed around the smart grid of the University Campus of Savona (Italy), which just completed in 2014, is analysed. The grid includes different cogenerative prime movers and a storage system to manage the thermal load demand. Through a time-dependent thermo-economic hierarchical approach developed by the Authors, the work aims at optimizing the management strategy of the different prime movers to satisfy the energy demand, taking into proper account both the energetic and economic aspects. The analysis was carried out considering two different layouts, with and without a conventional stratified thermal storage, to evaluate the impact of this component in the management of the district

A Case of Neurotrophic Keratopathy Concomitant to Brain Metastasis

We report a case of a 63-year-old Caucasian female referred to the cornea service of Clinica Oculistica with a neurotrophic corneal ulcer, decreased corneal sensitivity, absent corneal reflex, and decreased lacrimation. The medical record review was relevant for mastectomy and adjuvant therapy for breast cancer complicated by pontocerebellar angle metastasis. Eye patching and application of antibiotic and vitamin ointments were prescribed at first, without a significant improvement. Thus, treatment with autologous serum was started. In about two weeks, the cornea recovered and visual acuity improved with a residual corneal scarring. Finally, we should mention that, in our case, the main cause of the neurotrophic corneal ulcer could be identified in the previous trigeminal damage at the pontocerebellar angle and trigeminal ganglion. Sensory nerves play an important regulatory role via neuro-mediators on corneal wound healing, as denervation may interfere with cellular metabolism and inhibit mitosis, leading to an epithelial defect even with no direct damage

EXPERIMENTAL RESULTS AND TRANSIENT MODEL VALIDATION OF AN EXTERNALLY FIRED MICRO GAS TURBINE

ABSTRACT This paper presents the performance of the world's first Externally Fired micro Gas Turbine (EFmGT) demonstration plant based on micro gas turbine technology. The plant was designed by Ansaldo Ricerche (ARI) s.r.l. and the Thermochemical Power Group (TPG) of the Università di Genova, using the in-house TPG codes TEMP (Thermoeconomic Modular Program) and TRANSEO. The plant was based on a recuperated 80 kW micro gas turbine (Elliott TA-80R), which was integrated with the externally fired cycle at the ARI laboratory. The first goal of the plant construction was the demonstration of the EFmGT system at full and part-load operations, mainly from the control point of view. The performance obtained in the field can be improved in the near future using high-temperature heat exchangers and apt external combustors, which should allow the system to operate at the actual micro gas turbine inlet temperature (900-950 °C). This paper presents the plant layout and the control system employed for regulating the microturbine power and rotational speed. The experimental results obtained by the pilot plant in early 2004 are shown: the feasibility of such a plant configuration has been demonstrated, and the control system has successfully regulated the shaft speed in all the tests performed. Finally, the plant model in TRANSEO, which was formerly used to design the control system, is shown to accurately simulate the plant behavior both at steady-state and transient conditions