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Crowdsourcing involves releasing tasks on the internet for people with diverse backgrounds and skills to solve. Its adoption has come a long way, from scaling up problem-solving to becoming an environment for running complex experiments. Designing tasks to obtain reliable results is not straightforward as it requires many design choices that grow with the complexity of crowdsourcing projects, often demanding multiple trial-and-error iterations to properly configure. These inherent characteristics of crowdsourcing, the complexity of the design space, and heterogeneity of the crowd, set quality control as a major concern, making it an integral part of task design. Despite all the progress and guidelines for developing effective tasks, crowdsourcing still is addressed as an ``art'' rather than an exact science, in part due to the challenges related to task design but also because crowdsourcing allows more complex use cases nowadays, where the support available has not yet caught up with this progress. This leaves researchers and practitioners at the forefront to often rely on intuitions instead of informed decisions. Running controlled experiments in crowdsourcing platforms is a prominent example. Despite their importance, experiments in these platforms are not yet first-class citizens, making researchers resort to building custom features to compensate for the lack of support, where pitfalls in this process may be detrimental to the experimental outcome. In this thesis, therefore, our goal is to attend to the need of moving crowdsourcing from art to science from two perspectives that interplay with each other: providing guidance on task design through experimentation, and supporting the experimentation process itself. First, we select classification problems as a use case, given their importance and pervasive nature, and aim to bring awareness, empirical evidence, and guidance to previously unexplored task design choices to address performance concerns. And second, we also aim to make crowdsourcing accessible to researchers and practitioners from all backgrounds, reducing the requirement of in-depth knowledge of known biases in crowdsourcing platforms, experimental methods, as well as programming skills to overcome the limitations of crowdsourcing providers while running experiments. We start by proposing task design strategies to address workers' performance, quality and time, in crowdsourced classification tasks. Then we distill the challenges associated with running controlled crowdsourcing experiments, propose coping strategies to address these challenges, and introduce solutions to help researchers report their crowdsourcing experiments, moving crowdsourcing forward to standardized reporting.

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The equations governing the thermodynamic behavior of a military aircraft have been implemented by the Air Force Research Lab (AFRL) and other Integrated Vehicle Energy Technology Demonstration (INVENT) contributors into a cohesive, adaptable, dynamic aircraft simulation program in Mathworks' Simulink®. The resulting model known as the "Tip-to-tail" model meets the design specifications set forth by the INVENT program. The system consists of six intimately linked subsystems that include a propulsion subsystem (PS), air vehicle subsystem (AVS), robust electrical power subsystem (REPS), high power electric actuation subsystem (HPEAS), advanced power and thermal management subsystem (APTMS), and a fuel thermal management subsystem (FTMS). The model's governing equations are augmented with experimental data and supported by defined physical parameters. In order to address the problems associated with the additional power and thermal loads for in more electric aircraft (MEA), this research utilizes exergy analysis and mission-integrated synthesis/design optimization to investigate the potential for improvement in tip-to-tail design/performance. Additionally, this thesis describes the development and integration of higher fidelity transient heat exchanger models for use in the tip-to-tail. Finally, the change in performance due to the integration of new heat exchanger models developed here is presented. Additionally, this thesis discusses the results obtained by performing mission-integrated synthesis/design optimization on the tip-to-tail using heat exchanger design parameters as decision variables. These results show that the performance of the tip-to-thermal management subsystems improves significantly due to the integration of the heat exchanger models. These results also show improvements in vehicle performance due to the mission-integrated optimization. / Master of Science

Yes / Epigallocatechin gallate (EGCG), the main ingredient in green tea, holds promise as a potential treatment for pulmonary arterial hypertension (PAH). However, EGCG has many drawbacks, including stability issues, low bioavailability, and a short half-life. Therefore, the purpose of this research was to develop and optimize an inhalable EGCG nano-liposome formulation aiming to overcome EGCG’s drawbacks by applying a design of experiments strategy. The aerodynamic behaviour of the optimum formulation was determined using the next-generation impactor (NGI), and its effects on the TGF-β pathway were determined using a cell-based reporter assay. The newly formulated inhalable EGCG liposome had an average liposome size of 105 nm, a polydispersity index (PDI) of 0.18, a zeta potential of −25.5 mV, an encapsulation efficiency of 90.5%, and a PDI after one month of 0.19. These results are in complete agreement with the predicted values of the model. Its aerodynamic properties were as follows: the mass median aerodynamic diameter (MMAD) was 4.41 µm, the fine particle fraction (FPF) was 53.46%, and the percentage of particles equal to or less than 3 µm was 34.3%. This demonstrates that the novel EGCG liposome has all the properties required to be inhalable, and it is expected to be deposited deeply in the lung. The TGFβ pathway is activated in PAH lungs, and the optimum EGCG nano-liposome inhibits TGFβ signalling in cell-based studies and thus holds promise as a potential treatment for PAH. / This study was supported by Schlumberger Foundation’s faculty for the future in the form of PhD funding awarded to Fatma Haddad.

The widespread use of electronics in more avenues of consumer use is increasing. Applications range from medical instrumentation that directly can affect someone's life, down hole sensors for oil and gas, aerospace, aeronautics, and automotive electronics. The increased power density and harsh environment makes the reliability of the packaging a vital part of the reliability of the device. The increased importance of analog devices in these applications, their high voltage and high temperature resilience is resulting in challenges that have not been dealt with before. In particular packaging where insulative properties are vital use polymer resins modified by ceramic fillers. The distinct dielectric properties of the resin and the filler result in charge storage and release of the polarization currents in the composite that have had unpredictable consequences on reliability. The objective of this effort is therefore to investigate a technique that can be used to measure the polarization in filled polymer resins and evaluate reliable molding compounds. A valuable approach to measure polarization in polymers where charge release is tied to the glass transition in the polymer is referred to as thermally stimulated depolarization current (TSDC) technique. In this dissertation a new TSDC measurement system was designed and fabricated. The instrument is an assembly of several components that are automated via a LabVIEW program that gives the user flexibility to test different dielectric compounds at high temperatures and high voltage. The temperature control is enabled through the use of dry air convection heating at a very slow rate enabling controlled heating and cooling. Charge trapping and de-trapping processes were investigated in order to obtain information on insulating polymeric composites and how to optimize it. A number of material properties were investigated. First, polarization due to charges on the filer were investigated using composites containing charged and uncharged particles using quartz and ion exchange montmorillonite silicates in an epoxy matrix. The thermally-activated charge release shows a difference in the composite characteristics and preparation. This difference indicates that the trap levels depend on the de-trapping process and on the chemical nature of the trap site. Using a numerical approach to the release spectra, a model was developed to examine through short time testing, important parameters such as glass transition temperature, residual polarization, depolarization peak, window polarization modeling and activation energy of relaxations. Second the design of mold compounds that could combine manufacturing (temperature of molding), geometric (thickness of packaging material), composition (amount and size of filler) effects was developed using a novel design of experiments approach. The statistical DOE enabled the determination of which causes should be considered when designing a mold compound that has minimal polarization both as singular variables as well as combined variables. Finally, the DOE approach was used to develop a high temperature reliable molding compound through use of combined fillers of thermally conductive and nonconductive fillers having different shapes. Through the systematic approach to developing a technique and designing a mold compound addressing the multiple impacts on reliability of packaging, the dissertation provides an approach to the design, selection, performance and durability of molding compounds.

Pressing of metallic powders is a manufacturing process widely investigated in the research field and in the industry. This thesis project is focused on optimizing the pressing process of cemented carbide powder utilized for the production of triangular shaped cutting tool inserts. In particular, the filling of powder into the die cavity was investigated with respect to different pressing parameters. The aim of the project was to obtain a uniform density distribution of the powder into the die cavity, and hence to reduce the variation of the height of the insert obtaining more precise dimension of the latter. The tests were carried out at the Sandvik Coromant production department which is the creator of the project. The optimization of the pressing process was performed according to the Design of experiments theory. The dynamic of the sintering process was also investigated. The results showed a significant improvement in the filling of the die cavity and a significant decrease of the variation of the height of the inserts. The new insert obtained has more precise dimensions and is able to meet the more demanding requirements of the customers. The results achieved are directly applicable to a larger number of products, and indicate the direction to follow for further development of the manufacturing process.

Cheng and Wu (2001) introduced a method for response surface exploration using only one design by using a 3-level design to first screen a large number of factors and then project onto the significant factors to perform response surface exploration. Previous work generally involved selecting designs based on projection properties first and aliasing structure second. However, having good projection properties is of little concern if the correct factors cannot be identified. We apply Jones and Nachtsheim’s (2009) method for finding optimal designs with minimal aliasing to find 18, 27, and 30-run designs to use for single-step screening and optimization. Our designs have better factor screening capabilities than the designs of Cheng and Wu (2001) and Xu et al. (2004), while maintaining similar D-efficiencies and allowing all projections to fit a full second order model.

Denna studie är en kandidatuppsats om kvalitetssäkring där syftet har varit att undersöka hur tillverkningsföretag arbetar med kvalitetsarbete inom produktion för att öka mervärde åt kund och stärka företags konkurrenskraft. För att besvara syftet har följande frågeställningar utformats: ➢Hur sker prioritering av kvalitetsproblem i tillverkningsföretag? ➢Hur arbetar tillverkande företag med produktkvalitet och hur påverkar det företagets konkurrenskraft. Grunden till studien är en forskningsansats utifrån fallstudiemetoden där existerande vetenskapliga teorier har jämförts med ett verklighetsbaserat kvalitetsproblem. Den teoretiska referensramen har använts för att skapa förståelse och insikt för problemet i en bred kontext. Fallstudien har utförts på ett medelstort formsprutningsföretag i Mellansverige där kvalitetsbrister har resulterat i defekter på detaljer. Studiens ansats var aktionsforskning med både kvalitativa och kvantitativa metoder i form av observation, intervjuer, dokumentation och experiment. Resultaten visar att flera kriteriersom exempelvis rätt prioritering, standardisering och kunskap om processenhar betydelse för kvalitetsarbete samt att kriteriernas relationer är väsentliga för att säkerställa produktkvalitet. Från experimentet framkomdet att direktiv från den vetenskapliga referensramen till parameterinställningar var tvärt emot vad experimentets utfall visade. Det är dock viktigt att uppmärksamma att förändringar av parameterinställningar kan leda till förbättring av en defekt men kan ge uppkomst till en annan. Därmed är det väsentligt att vid komplexa processer ha fungerande kommunikationsamt bred kunskap och insikt iprocessen. Genom att fokusera på kvalitetsarbete kan företag öka kapacitet och kundnöjdhetvilket skapar grunden till konkurrenskraft.

Atualmente o Projeto de Experimentos (DOE) vem sendo largamente utilizado para determinar os fatores de projetos e processos mais significativos afetando uma variável resposta e para estabelecer modelos empíricos entre os fatores, entretanto este método ainda é pouco utilizado e processo de forjamento a quente. O presente trabalho analisa a influência individual e cumulativa de alguns parâmetros controláveis de um processo de forjamento a quente em matriz fechada na força de prensagem necessária para sua realização. Esta análise foi realizada utilizando a técnica de Projeto de Experimentos (DOE). Para a determinação da influência dos parâmetros de processo selecionados na variável resposta do Projeto de Experimentos (DOE), uma série de ensaios variando o lubrificante utilizado, o diâmetro da geratriz e a temperatura de forjamento foram realizados. A variável resposta para o experimento foi definida como a força de prensagem exigida do equipamento para a realização do forjamento. Para este trabalho foi utilizado o material ABNT 4140 fornecido em barras trefiladas de 28,6mm (1.1/8″) posteriormente forjado a quente em matriz fechada. Os resultados mostraram que o fator que mais influencia na força de prensagem para a situação ensaiada é o lubrificante. Os demais fatores, mesmo combinados, não apresentaram uma influência significativa na variável resposta. O presente estudo demonstra que é possível a utilização de técnicas de ajuste e definição de parâmetros de processo de forjamento a quente de maneira confiável e sem a necesside da aplicação dos complexos programas de simulação computacional e os métodos de tentativa e erro ainda presentes na indústria. Finalmente este trabalho reforça a versatilidade do Projeto de Experimentos (DOE) ainda pouco aplicado em processos de forjamento. / Nowadays the Design of Experiments (DOE) has been widely used to determine the most significant project and process factors affecting a response variable and to establish empirical models among the factors, although this method is still little used and the process of hot forging. This work analyzes the individual and cumulative influence of some controllable parameters in a closed die hot forging process in the pressing force required for its realization. This analysis was performed using a Design of Experiments (DOE) method. To determine the influence of variable factors selected in response Design of Experiments (DOE), a several tests varying the lubricant, the diameter of the billet and the forging temperature was performed. The response variable for the experiment was defined as pressing force. For this study, it was used the ABNT 4140 steel provided in drawn bars of 28,6mm (1 1/8 ″). The fator that had more influence over the pressing force was the lubricant. Other factors, whether or not combined, did not show a significant influence on the response variable. This study demonstrates that it is possible use techniques to set hot forging process parameters reliably and without necesside the application of complex computer simulation programs or the trial and error system. Finally, this work reinforces the versatility of Design of Experiments (DOE) wich is still little used in forging processes.