This thesis uses data from a real-world distributed system to develop a model for realistic load tests, and analyzes the results of several different workload scenarios on a test deployment. The research focused on characterizing the workload of the real-world Pretio system using logs captured from the production deployment, modelling a workload from those logs, and analyzing the impact on a test deployment of the system of a series of scenarios providing different parameters to the model. The results were evaluated by testing the response time distributions across multiple test runs for statistical similarity. / Graduate

The increasingly personal and ubiquitous capabilities of computing—everything from smartphones to virtual reality—are enabling us to build a brave new world in the digital realm. Despite these advances in the virtual world, our ability as end-users to transform the physical world still remains limited. The emergence of low-cost fabrication technology (most notably 3D printing) has brought us a dawn of making, promising to empower everyday users with the ability to fabricate physical objects of their own design. However, the technology itself is oblivious of the physical world—things are, in most cases, assumed to be printed from scratch in isolation from the real world objects they will be attached to and work with. To bridge this ‘gulf of fabrication’, my thesis research focuses on developing fabrication techniques with design tool integration to enable users to expressively create designs that can be attached to and function with existing real-world objects. Specifically, my work explores techniques that leverage the 3D printing process to create attachments directly over, onto and around existing objects; a design tool further enables people to specify and generate adaptations that can be attached to and mechanically transform existing objects in user-customized ways; a user-driven approach allows people to express and iterate structures that are optimized to support existing objects; finally, a library of ‘embeddables’ demonstrate that existing objects can also augment 3D printed designs by embedding a large variety of material to realize different properties and functionalities. Overall my thesis aspires to make fabrication real—enabling people to express, iterate and fabricate their designs that closely work with real-world objects to augment one another.

Neuroscience, psychology, and many other fields, such as anthropology or philosophy, try to understand our cognition and cognitive processes. However, as time passed, new views on cognition emerged. One of the newest views on cognition, known as 4E cognition, refers to embedded, embodied, extended, and enacted cognition. Alternatively, to put it in simpler terms, our cognition and cognitive processes emerge from us by being in our environment, interacting with our environment, and enacting our actions within our environment. Although the need to study human cognition from a higher perspective led to the emergence of cognitive sciences, despite these advancements, our experimental methods have stayed relatively unchanged for the past centuries. The recent trends in cognitive science and related fields lean toward real-world experimentation. The main argument for real-world experimentation is the ecological validity of our experimentation and finding. However, despite all the positive voices advertising for real-life experimentation, there are also significant concerns and voices against such a movement. Real-world is full of dynamics and sources of noises and events no one has studied in detail before. As alluring as the idea of moving out of the lab and doing experiments in real life is, the challenges of real-life experimentation should not be neglected, at least with our current methods and tool kits. However, one does not need to entirely abandon the control of the lab environment to get closer to real-life experimentation. Immersive virtual reality experiences can offer a close to the real-life and interactive foundation for conducting cognitive science experiments. Virtual reality experiments can offer the same level of control over the conditions and precision in measurements as laboratory-based experimentation yet enable a realistic, immersive environment to simulate real-life situations. This dissertation seeks to investigate the ecological validity of immersive virtual reality experimentation. The investigation tries to see if virtual reality experimentation can augment the lab-based experiments to simulate closer to real-life situations. The second point of focus is on the notion of ecological validity. Here we tried to investigate which factor among realistic cues, environment, or interaction with the environment plays a vital role in improving the findings of cognitive science experiments. This dissertation seeks to answer these questions with different experiments made and conducted using immersive virtual reality simulations. These studies first investigate virtual reality technologies' current state of the art. These experiments push the limits of what others previously performed in virtual reality experimentation in terms of immersion and realism. We studied ecological validity using these environments. This work examines the hypothesis that "realism" indeed matters and, more importantly, that realism in the interaction with the environment can give us more understanding regarding our observations. Finally, we will observe participants in their behavior using virtual reality experiments with minimal to no intervention to validate the effectiveness of virtual reality experimentation. Of course, the studies presented in this work also have further research questions to answer. These research questions include Gaze behavior during tool interaction or planning while sorting objects on a shelf is an example of investigating low-level cognitive processes. The role of perspective on the moral judgments in trolley dilemma situations or change of attitude and acceptance toward self-driving vehicles is more on the psychological aspects of cognition. However, when added together, the observations gained in each study offer solid arguments toward not only the benefits of virtual reality experimentation but the importance of studying cognition within a natural context in real work with naturalistic interactions. This dissertation provides arguments in favor of virtual reality as a suitable experimentation tool and environment in the absence of standard and precise real-life experimentation methods as a way to simulate real-life experiences in our experiments.

Design / My work explores methods of creating illusions that make the imaginary and the real worlds appear to co-exist. More specifically, my animations look at ways of connecting the real and fantastical by using “low tech” materials. This report discusses existing work that combines animation with video-installation, live-performance, and advertisements; analyzes my research trajectory, explains my methodology for producing new hybrid work in animation; and then describes my projects. Each project is derived from a matrix I developed that forces integrations between two sets of criteria: (1) physical world action, objects and space, and (2) computer-generated images, representational images in an imaginary state and objects in physical space in an imaginary state. / text

The container loading problem considered in this thesis is to determine placements of a set of packages within one or multiple shipping containers. Smaller packages are consolidated on pallets prior to being loaded in the shipping containers together with larger packages. There are multiple objectives which may be summarized as fitting all the packages while achieving good stability of the cargo as well as the shipping containers themselves. According to recent literature reviews, previous research in the field have to large extent been neglecting issues relevant in practice. Our real-world application was developed for the industrial company Atlas Copco to be used for sea container shipments at their Distribution Center (DC) in Texas, USA. Hence all applicable practical constraints faced by the DC operators had to be treated properly. A high variety in sizes, weights and other attributes such as stackability among packages added complexity to an already challenging combinatorial problem. Inspired by how the DC operators plan and perform loading manually, the batch concept was developed, which refers to grouping of boxes based on their characteristics and solving subproblems in terms of partial load plans. In each batch, an extensive placement heuristic and a load plan evaluation run iteratively, guided by a Genetic Algorithm (GA). In the placement heuristic, potential placements are evaluated using a scoring function considering aspects of the current situation, such as space utilization, horizontal support and heavier boxes closer to the floor. The scoring function is weighted by coefficients corresponding to the chromosomes of an individual in the GA population. Consequently, the fitness value of an individual in the GA population is the rating of a load plan. The loading optimization software has been tested and successfully implemented at the DC in Texas. The software has been proven capable of generating satisfactory load plans within acceptable computation times, which has resulted in reduced uncertainty and labor usage in the loading process. Analysis using real sea container shipments shows that the GA is able to tune the scoring coefficients to suit the particular problem instance being solved.

The aim of this master thesis was to gather and analyze the real-world XQuery programs. The data gathering process is performed using the crawler. The thesis contains analysis of different crawlers and the most suitable crawler was chosen. The crawler was modified, so that it did not overload servers, gathered the right data and was able to pause. Before the data gathering we analyzed where to start gathering and how long should it took. When the data was gathered, they needed to be cleaned and validated. The subjects of the analyses were use of the XQuery language and occurrences of XQuery grammar symbols. Combination of the XML representation of XQuery programs and XPath expressions for querying this representation was used to perform these analyses. XQConveror was used to create this XML representation. The main contributions of this thesis are the gathered data and the first real-world XQuery programs analysis.

The aim of this thesis was to gather and analyze the real-world XQuery programs. The data gathering process is usually performed using the crawler. Part of the thesis was to analyze different crawlers and to choose the most suitable one. The crawler was then modified, so it would not overload servers, gather the right data and be able to pause. Before main gathering two problems had to be solved - where to start the gathering and how long it will take. After the data were gathered, they were cleaned, corrected and validated. The subject of the analysis was usage of the XQuery language and its grammar symbols. We also analyzed the XML documents used by XQuery programs and outputs from the XQuery programs. The main contribution of this thesis is the amount of the gathered data (in comparison with other sources), as well as gathering XML documents which are being queried, using Analyzer for analyzing the real-world XQuery programs and running this real-world XQuery programs over gathered XML documents.

In the first chapter, I investigate reputational effects of the disclosure of negative information in a market affected by adverse selection. A series of recent discoveries has increased consumer concern over the presence of counterfeits in the market for fine and rare wine. For the thousands of bottles sold at auction each year, house reputation is used as a quality assurance mechanism to signal product authenticity. Using sales data from 2005-2015 for the ten largest auction houses, I study consumer reaction following two recent disclosures of an auction house having offered or sold counterfeit wine. My identification strategy to examine reputation involves a series of triple difference regressions analyzing equilibrium prices and quantities. I discover one house experienced no losses following a 2008 incident involving 107 counterfeit bottles. However, three houses associated with a 2012 incident involving thousands of bottles were found to have suffered significant reputation losses following the incident. These losses are demonstrated by a 3-8% decrease in equilibrium sales prices and a 6-9% decrease in sales quantities in the year following the disclosure. The second chapter of my dissertation involves the transitivity of stated preferences. Revealed preference theory states that, in order for an individual’s preferences to be consistent with utility maximization, they must satisfy the principle of transitivity. Any deviations from this principle result in a logically inconsistent response pattern. I develop a new framework to study the rationality of stated preferences, accounting for both the number and severity of non-transitive responses an individual makes. I implement this method using a nationally representative survey of 3,234 respondents from the U.S. general population and discover that more than 52% of the population exhibit non-transitive preferences. In addition to measuring the number and severity of non-transitive preferences exhibited by each respondent, another aim of this manuscript is to evaluate the relationship between response transitivity and the individual outcomes of each respondent under the premise that high quality decisions are the result of greater decision-making ability. After controlling for demographic characteristics including age, education, race, gender, ethnicity, and work status, non-transitive patterns are correlated with lower incomes and poorer health.

Abstract The amount of digital data surrounding us has exploded within the past years. In industry, data are gathered from different production phases with the intent to use the data to improve the overall manufacturing process. However, management and utilization of these huge data sets is not straightforward. Thus, a computer-driven approach called data mining has become an attractive research area. Using data mining methods, new and useful information can be extracted from enormous data sets. In this thesis, diverse industrial problems are approached using data mining methods based on similarity. Similarity information is shown to give an additional advantage in different phases of manufacturing. Similarity information is utilized with smaller-scale problems, but also in a broader perspective when aiming to improve the whole manufacturing process. Different ways of utilizing similarity are also introduced. Methods are chosen to emphasize the similarity aspect; some of the methods rely entirely on similarity information, while other methods just preserve similarity information as a result. The actual problems covered in this thesis are from quality control, process monitoring, improvement of manufacturing efficiency and model maintenance. They are real-world problems from two different application areas: spot welding and steel manufacturing. Thus, this thesis clearly shows how the industry can benefit from the presented data mining methods.

Doctor Educationis / The overarching purpose of this research study was to ascertain the deliberations preservice mathematics teachers engage with when they construct alternative mathematical models for social phenomena. The study is situated within the mathematical competencies and, in particular, on the evaluation competency with the possibility of developing alternative models flowing from the evaluation. Twenty fourth-year pre-service mathematics teachers participated in the completion of three different mathematical modelling tasks on which the analysis was based. The data collected was analysed qualitatively. The researcher exploited a thematic analysis design to investigate how pre-service mathematics teachers build alternative models.