In the perspective of the "Net Zero Energy Buildings" as specified in the EPBP 2010/31/EU, herein a modular unglazed solar thermal facade component for facilitating the installation of active solar thermal facades has been conceived and designed to answer three considerations: (1) easily installable elements, offering high modularity to be sized for the specific needs of the buildings considered, (2) low-price unglazed technology, given by the industrial process already developed for the fridge evaporators, and (3) versatile modules to be used for both new buildings and for existing buildings for energy retrofitting. The existing buildings stock offers a high-potential opportunity to improve the energy efficiency when using such a system. Indeed, the building envelope elements have a significant impact on energy consumptions and performances of the building, and this is a key aspect to consider during renovation. Considering buildings integrating solar thermal (BIST) by the means of facade retrofitting of solar thermal collectors (STC) opens up new challenges for engineers. Facade usage, compared to the traditional roof installations, offers two interesting potentialities: (1) increased available surfaces, and (2) minimization of the unwanted overheating problem, that appears in summer, thanks to the vertical tilt (as the energy production is almost constant over the year). This allows sizing the STC according to the actual heat needs and avoids as much as possible energy fluxes mismatch. The design methodology of such a modular component is the main contribution of the PhD work. The challenges are tackled via a parametric approach. Dynamic simulation tools support the design choices for the energy systems of BIST and to optimize the interactions between the envelope and the STC with the criteria of reducing the overall energy consumption. This methodology is described and applied to the design of a modular prototype of an innovative facade component integrating unglazed STC. We first analyze a variety of typologies of buildings as potential commercial targets of the facade component of unglazed STC integrated facade element. Both residential and non residential buildings are considered. The purpose of this analysis is to match the heat loads for properly sizing the facade elements for each typology. Benchmark models of buildings from the Department of Energy are used such as multifamily houses, hospitals, big and small hotels, schools, offices. These are simulated through EnergyPlus in three European locations (Stockholm, Zurich and Rome) in order to define the yearly heat loads for domestic hot water (DHW) and space heating (SH) needs. Finally, the prototype is conceived and designed as a low-cost product to implement into facades with the criteria of optimizing the energy production. The unglazed STC is combined with a simple configuration of combisystem in order to define some rule of thumbs through Trnsys. By the fact that the energy is produced at lower temperatures, if compared with glazed flat plate collectors, this technology is potential applicable to those buildings having the proper heat loads and the suitable system layout.

In the perspective of “nearly zero energy buildings” as foreseen in the EPBD 2010/31/EU, herein a prototype of a wooden prefabricated BiPV wall is conceived, designed, built and tested. The prototype key concepts, identified according to the recommendations of the IEA Task 41 research project, are: multi-functionality, prefabrication, sustainability and integration. The prototype design is the result of a theoretical study which takes into account both architectural integration aspects and energy performance issues. The latter in particular, is based on the evaluation and improvement of both PV and building-related aspects, through the investigation and implementation of low-cost passive strategies to improve the overall BiPV performance. A modular specimen of the prototype was built thanks to an industrial collaboration and tested through an experimental approach, based on the combination of several phases performed in two test facilities (i.e. INTENT lab and SoLaRE-PV lab) by means of original experimental set-up. The effectiveness of the proposed BiPV prototype configuration is proven by comparing the results of the experiments with monitored data of two BiPV systems (a roof and a façade system) located in South Tyrol (North of Italy). The experimental results are then generalized, providing significant data and experimental expressions for a deeper understanding of BiPV systems energy performance.

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För att möta den så kallade digitala generationen och höja elevers motivation och måluppfyllelse satsar fler och fler skolor på 1:1. Det innebär att varje elev och lärare får tillgång till varsin bärbar dator. Den forskning som finns om 1:1-satsningar fokuserar i hög grad på teknologin, ifråga om hur denna står i relation till elevresultat, elev- och lärarattityder, etc., men utelämnar de pedagogiska synsätten i 1:1-satsningarna. Det är denna lucka som är utgångspunkten i uppsatsen. Med fokus på fyra 1:1-verksamma pedagoger ämnar denna uppsats undersöka de pedagogiska synsätt som omgärdar 1:1-verksamhet. Frågeställningarna behandlar datoranvändning, elevsyn, kompetensutveckling och digital kompetens. Förutom intervjuer med pedagogerna baseras undersökningen på styrdokument, kommunala IT/IKT-strategier, de aktuella skolornas IT-strategier samt observationer i pedagogernas klasser. Elevdatorn används inom en rad olika områden i skolan. Hur pedagogen väljer att använda datorn i undervisningen skiljer sig mellan det tillfrågade inom ett brett svarsområde. Elevdatorn används i alltifrån den mer traditionella klassrumsundervisningen till ett mer nytänkande lärande. Elevdatorn kan även ha funktionen av ett administrativt verktyg som bidrar till förenkling i den befintliga undervisningen. Avsaknaden av en gemensam syn på vad det innebär att satsa på 1:1 och vad som krävs för att en satsning ska vara framgångsrik är en bidragande orsak till att de undersökta projekten ser så pass olika ut. Att pedagogerna inte får någon större möjlighet till kompetensutveckling utan istället är beroende av sitt eget engagemang är också en bidragande orsak till detta. En gemensam syn finns kring behovet av att utveckla elevernas digitala kompetens i syfte att förbereda dem för en allt mer globaliserad och digitaliserad omvärld.

The project set out to construct a proof of concept for surface deformation in the Unity Engine using available assets and tools compatible with the Unity Engine, and via the proof of concept investigate which factors in a mesh deformation simulation that affects performance in terms of frames per second, memory usage and usability the most. This while looking into suitable data structures in the Unity Engine for handling expected data in a physics simulation of a surface deformation, such that of mining or scraping a cave wall. The project aims to answer these questions via testing and trail and error, performing tests while recording data which is plotted and discussed. To save time and start testing faster the usage of a premium assets called Digger Pro is used, allowing for quick set up of mesh manipulation inf both editor and play mode. Testing shows that one of the major factor for performance degradation is mesh resolu-tion, as it directly contributes to an increase in data points that needs to be kept track of and calculated. The Unity Engine and Digger PRO man-ages fairly well to stay above the targeted 30 frames per second limit even with medium level settings for meshes, all while maintaining acceptable memory usage levels. All this ties into the idea of an increased usage of digital twins in many different scenarios, and therefore the scientific community’s view on digital twins main challenges are summarized and discussed, hoping to shed further light on the current status of digital twin technology.

Functional connectivity represents a powerful approach to describe the intrinsic activity of the brain. It reveals the organization and correlations among anatomically separated regions supporting similar cognitive and sensory processes. Using functional Magnetic Resonance Imaging (fMRI), the recurrent spatial characteristics of these patterns have been extensively explored in the adult brain and their disruption has been found to be associated with psychiatric and developmental disorders. Unveiling the processes of emergence of resting state networks at a very early stage of life could shed light on the neuronal origins of these diseases. However, the study of the inception and development of functional connectivity in the newborn brain poses exceptional challenges, due to the complexity of dealing with non-compliant subjects. To this end, cortical activity at birth can be investigated using functional Near Infrared Spectroscopy (fNIRS) that represents a promising non-invasive neuroimaging method for developmental studies. In the present thesis, I applied fNIRS to assess functional connectivity in term neonates. The first part of the dissertation is dedicated to investigating the maturation of a specific resting state network, the Default Mode Network, within the first 48 hours of life. The study aimed to examine its emergence, for the first time, using optical imaging on newborns immediately after birth. While the majority of fMRI literature focused on large-scale spatial patterns, I took a different approach measuring an intrinsic and localized fingerprint feature of the network, consistently detected in adult subjects. In the second part of the dissertation, I aimed at improving the anatomical representation of brain connectivity, inferred only from signals collected at the scalp. Thus, I developed and validated a method for the reconstruction of spatially distributed functional signals on a dedicated template for term newborn subjects. The intent is to promote the shift from a sensor space description (one signal for each channel) to a source space representation in which the origin of the signal is reconstructed with better anatomical fidelity. The reliability of the reconstruction method was tested on synthetic and real data. In the former case, I simulated spatially correlated neural activity in the cortex, thus enabling assessment of the reconstructed images against a ground-truth map. Analyses of functional connectivity in both sensor and source space showed that the Default Mode Network is still immature at birth, with a lack of homotopic correlation in the lateral parietal cortices, and no evidence of anticorrelation with the Dorsal Attention Network, a well established feature in the adult brain. Overall the work presented in the thesis contributes to the understanding of functional connectivity in the infantâ€TMs brain and provides useful tools for source-based connectivity analysis and for probe design and optimization.

The latest generation of semiconductor wafer fabs produce Integrated Circuits (ICs) on silicon wafers of 300mm diameter. In this dissertation, we address the following two types of (new) scheduling problems that are encountered in this generation of wafer fabs: multiple-lots-per-carrier scheduling problem (MLCSP) and integrated automated material handling and lot scheduling problem (IMHLSP). We consider several variations of the MLCSP depending upon the number of machines used, the prevailing processing technology of the machines, and the type of objective functions involved. For the IMHLSP, we study two instances, one with infinite number of vehicles and the other with finite number of vehicles. We begin by introducing a single-machine, multiple-lots-per-carrier with single-wafer-processing-technology scheduling problem for the objective of minimizing the total completion time (MLCSP1). The wafer carrier is a front-opening unified pod (FOUP) that can hold a limited number of wafers. The problem is easy to solve when all the lots are of the same size. For the case of different lot sizes, we first relax the carrier (FOUP) capacity and propose a dynamic programming-based algorithm, called RelaxFOUP-DP, which enables a quick determination of its optimal solution that serves as a lower bound for the problem with limited FOUP capacity. Then, a branch-and-bound algorithm, designated as MLCSP1-B&B, is developed that relies on the lower bound determined by the RelaxFOUP-DP algorithm. Numerical tests indicate that MLCSP1-B&B finds optimal solutions much faster than the direct solution of the MLCSP1 model by the AMPL CPLEX 10.1 Solver. In fact, for the medium and low density problems, the MLCSP1-B&B algorithm finds optimal solutions at the starting node (node zero) itself. Next, we consider a single-machine, multiple-lots-per-carrier with single-carrier-processing-technology scheduling problem for the objective of minimizing total completion time (MLCSP2). As for the case of MLCSP1, the optimal solution for the case in which all the lots are of the same size can be obtained easily. For the case of different lot sizes, we determine a lower bound and an upper bound for the problem and prove the worst-case ratios for them. Subsequently we analyze a two-machine flow shop, multiple-lots-per-carrier with single-wafer-processing-technology scheduling problem for the objective of minimizing the makespan (MLCSP3). We first consider a relaxed version of this problem, and transform the original problem to a two-machine flow shop lot streaming problem. Then, we propose algorithms to find the optimal capacitated sublot sizes for the case of lots with (1) the same ratio of processing times, and, (2) different ratios of processing times on the machines. Since the optimal solutions obtained from the lot streaming problem may not be feasible to the MLCSP3, we develop heuristic methods based on the heuristic procedures for the bin packing problem. We develop four heuristic procedures for lots with the same ratio of processing times, and another four procedures for lots with different ratios of processing times on the machines. Results of our numerical experimentation are presented that show that our heuristic procedures generate almost optimal solutions in a matter of a few seconds. Next, we address the integrated automated material handling and lot scheduling problem (IMHLSP) in the presence of infinite number of vehicles. We, first, propose a new strong hybrid model, which has the advantages of both segregate and direct models. In the segregate model, a job is always transferred to the stocker after its completion at a station, while in the direct model, it is transferred to the next machine in case that machine can accommodate the jobs; otherwise, the job will stay at current station. The decisions involved in the strong hybrid model are the sequence in which to process the lots and a selection between the segregate and direct models for each lot, whichever optimizes system performance. We show that, under certain conditions about the processing times of the lots, the problem can be approximated by the cases of either infinite buffer or zero-buffer at the machines. Hence, we consider all three cases of the IMHLSP in this chapter, namely, infinite buffer, zero-buffer, and limited buffer sizes. For the strong hybrid model with limited buffer size, we propose a branch-and-bound algorithm, which uses a modified Johnson's algorithm to determine a lower bound. Two upper bounds for this algorithm are also determined. Results of our numerical investigation indicate that our algorithm finds optimal solutions faster than the direct solution of the IMHLSP model by the AMPL CPLEX 10.1 Solver. Experimental results also indicate that for the same problem size, the times required to solve the IMHLSP model with interbay movements are larger than those for intrabay movements. Finally, we investigate the IMHLSP in the presence of limited number of vehicles. Due to the complex nature of the underlying problem, we analyze small-size versions of this problem and develop algorithms for their solution. For some of these problems, we can find optimal solutions in polynomial time. Also, based on our analysis on small-size systems, we have shown why some real-time dispatching (RTD) rules used in real fabs are expected to perform well while not the others. In addition, we also propose some new and promising RTD rules based on our study. / Ph. D.

Per- and polyfluoroalkyl substances (PFAS) are a class of man-made contaminants of increasing human health concern due to their resistance to degradation, widespread occurrence in the environment, bioaccumulation in human and animal organ tissue, and potential negative health impacts. Drinking water is suspected to be a primary source of human PFAS exposure, so the US Environmental Protection Agency (US EPA) has set interim and final health advisories for several PFAS species that are applicable to municipal water supplies. However, private drinking water supplies may be uniquely vulnerable to PFAS contamination, as these systems are not subject to EPA regulation and often include limited treatment prior to use for drinking or cooking. The goal of this study was to determine the incidence of PFAS contamination in private drinking water supplies in two counties in Southwest Virginia (Floyd and Roanoke), and to examine the potential for reliance on citizen-science based strategies for sample collection in subsequent broader sampling efforts. Samples for inorganic ions, bacteria, and PFAS analysis were collected on separate occasions by homeowners and experts at the home drinking water point of use (POU) in 10 Roanoke and 10 Floyd County homes for comparison. Experts also collected an outside tap PFAS sample. At least one PFAS compound was detected in 76% of POU samples collected (n=60), with an average total PFAS concentration of 23.5 parts per trillion (ppt). PFOA and PFOS, which are currently included in EPA health advisories, were detected in 13% and 22% of POU samples, respectively. Of the 31 PFAS species targeted, 15 were detected in at least one sample. On average, a single POU sample contained approximately 3 PFAS, and one sample contained as many as 8 different species, indicating that exposure to PFAS in complex mixtures is worth noting. Although there were significant differences in total PFAS concentrations between expert and homeowner collected samples (Wilcoxon, alpha = 0.05), it is unclear whether this difference was due to contamination by the collector or the water usage and time of day of sampling (i.e. morning, afternoon). It is worth noting that there was no significant difference in the number of PFAS species in the samples collected by homeowners and experts. Given the considerable variation in PFAS detections between homes, future studies reliant on homeowner collection of samples appears possible given proper training and instruction to collect at the same time of day (i.e. first thing in the morning). / Master of Science / Per- and polyfluoroalkyl substances (PFAS) belong to a large family of manmade compounds that are commonly used in a variety of household and consumer products due to their unique water and stain resistant properties. PFAS compounds are not easily broken down in the environment and have been detected globally in air, soil, and water samples. In addition to their environmental detections, PFAS are slow to be removed from the body after ingestion and known to cause negative health effects in concentrations less than one part per trillion. Drinking water is considered to a main source of PFAS consumption for humans; as such, the US Environmental Protection Agency (US EPA) has set strict, but not legally binding, interim and final health advisories (HA) for four types of PFAS. However, these health advisories only apply to public water services and do not cover private drinking water systems, such as wells or springs, which are the full responsibility of the well owner. Private drinking water system users often do not treat their water before drinking which may make these systems uniquely vulnerable to PFAS contamination. This study focused on 20 total homes, 10 in Roanoke County and 10 in Floyd County to see if PFAS was present and to determine whether or not homeowners would be able to collect their own samples for PFAS analysis at home as accurately as researchers or experts with proper instructions. Homeowners and experts collected drinking water samples inside at a point of use (POU), usually at a kitchen faucet, and outside of the home, usually from a tap. PFAS were present in 76% (n=60) of POU samples, with an average combined concentration of 23.5 parts per trillion (ppt). The two most well studied PFAS, PFOA and PFOS were detected in 13% and 22% of POU samples, respectively. It was also common to detect at least 3 PFAS in a single sample. Although there were differences in total average concentrations of PFAS in samples collected by homeowners and experts, variation could be caused by several factors indicating that with proper training and instruction it is likely future studies could still rely on homeowners to collect samples for PFAS analysis.