736 research outputs found
Modernist Urbanism in the Age of Automobility: Producing Space in the Suburbs of Toronto and Prague
Theorizing the effects of the expanding system of automobility has been an important area of inquiry in urban studies. What remains largely absent, though, are concrete investigations into the relationships between automobility and the transformations and production of urban space. Automobility is defined by its contradictions. This dissertation explores how urban planners, architects and theorists have historically responded to and attempted to resolve the contradictions of automobility. I locate these responses within the broader theoretical framework of the production of space, considering how the mode of conceiving space from the 1920s on was directly related to the car and the expanding system of automobility. Automobility as an assemblage of objects, ideologies, and institutions was central to the way architects and planners conceived of urban space: as a work of art. I argue that this conception of space circulated globally, which I show through the work of the Czechoslovak architectural avant-garde theorist Karel Teige in the 1920s and the urban theorist Humphrey Carver in post-war Canada.
In this dissertation I explore automobility and the production of space by way of two post-war suburbs: Jižnà město (South City) in Prague and Willowdale in Toronto. Both places were considered as solutions to problems associated with automobility and both were key nodes in the circulation of ideas on modernist urbanism. I argue that the building of South City and the rebuilding of Willowdale are the culmination of the circulation of a modernist urbanism across space and over time that attempted to respond to the forces of urbanization and automobility through planning and designing the suburb.
Overcoming the contradictions of automobility will involve more than just new technologies of mobility—urban planners, architects and theorists will have to consider the production of a wholly different space for urban life. To move beyond automobility means accounting for the ways the system of automobility unevenly affects city and suburban dwellers. In an attempt to offer a critique of the city-suburb dichotomy, this dissertation argues that to go “beyond automobility” means collapsing the separations that mark both modernism and automobility
Taking Shelter: Teaching and Learning in the House that Technology Built
In The Real World of Technology, Ursula Franklin draws on the metaphor of the “house that technology has built” to illustrate the all-encompassing and pervasive environment of technology. In this paper, I take this metaphor literally by turning to our transformed houses and homes during the pandemic. By way of illustration, I draw on my experiences teaching online, which began in March 2020. In Fall 2020, I designed and taught a 4th-year undergraduate course with the title “Taking Shelter” which gave students an opportunity to work through and reflect on the changing nature of house and home, while calling attention to the transformed technological environment in which we were working. Through attention to the places we live and work in everyday, the paper imagines a foundation built on ecological principles that takes account of technology as environment, milieu and system
Merger Enforcement Statistics: 2001-2020
This article summarizes merger enforcement data for the period between 2001 and 2020, using a database created by the authors. The database lists the identity and outcome of every transaction that received a second request during this 20-year period. The database also lists the identity and outcome of every challenge to an already-consummated merger during the period. To our knowledge, it is the only complete database for the listing and outcomes of all such transactions. The goal of creating the database is to provide further information on merger enforcement, which hopefully can inform policy and spur additional analysis. We describe the data and various results, both in aggregate and across Presidential Administrations. These include rates of second request, challenges, consent decrees, abandonments and trial outcomes. We also provide a complete listing of all merger challenges
Minimization of Surface Impurities in Anodized Aluminum
Anodized aluminum is commonly used to create wear-resistant parts for process tools used in the semiconductor industry. Sinc microchips require high purity manufacturing environments[1], surface impurities on tooling needs to be minimized.
It has been determined that anodized aluminum parts are one source of contamination. This project investigates the source of trace elements in anodized aluminum 6061 parts and ways to reduce them
CRDIAC: Coupled Reactor Depletion Instrument with Automated Control
When modeling the behavior of a nuclear reactor over time, it is important to understand how the isotopes in the reactor will change, or transmute, over that time. This is especially important in the reactor fuel itself. Many nuclear physics modeling codes model how particles interact in the system, but do not model this over time. Thus, another code is used in conjunction with the nuclear physics code to accomplish this. In our code, Monte Carlo N-Particle (MCNP) codes and the Multi Reactor Transmutation Analysis Utility (MRTAU) were chosen as the codes to use. In this way, MCNP would produce the reaction rates in the different isotopes present and MRTAU would use cross sections generated from these reaction rates to determine how the mass of each isotope is lost or gained. Between these two codes, the information must be altered and edited for use. For this, a Python 2.7 script was developed to aid the user in getting the information in the correct forms. This newly developed methodology was called the Coupled Reactor Depletion Instrument with Automated Controls (CRDIAC). As is the case in any newly developed methodology for modeling of physical phenomena, CRDIAC needed to be verified against similar methodology and validated against data taken from an experiment, in our case AFIP-3. AFIP-3 was a reduced enrichment plate type fuel tested in the ATR. We verified our methodology against the MCNP Coupled with ORIGEN2 (MCWO) method and validated our work against the Post Irradiation Examination (PIE) data. When compared to MCWO, the difference in concentration of U-235 throughout Cycle 144A was about 1%. When compared to the PIE data, the average bias for end of life U-235 concentration was about 2%. These results from CRDIAC therefore agree with the MCWO and PIE data, validating and verifying CRDIAC. CRDIAC provides an alternative to using ORIGEN-based methodology, which is useful because CRDIAC's depletion code, MRTAU, uses every available isotope in its depletion, unlike ORIGEN, which only depletes the isotopes specified by the user. This means that depletions done by MRTAU more accurately reflect reality. MRTAU also allows the user to build new isotope data sets, which means any isotope with nuclear data could be depleted, something that would help predict the outcomes of nuclear reaction testing in materials other than fuel, like beryllium or gold
Non-linear relationships between density and demographic traits in three Aedes species
Understanding the relationship of population dynamics to density is central to many ecological investigations. Despite the importance of density-dependence in determining population growth, the empirical relationship between density and per capita growth remains understudied in most systems and is often assumed to be linear. In experimental studies of interspecifc competition, investigators often evaluate the predicted outcomes by assuming such linear relationships, ftting linear functions, and estimating parameters of competition models. In this paper, we experimentally describe the shape of the relationship between estimated population rate of change and initial density using laboratory-reared populations of three mosquito species. We estimated per capita growth rate for these experimental populations over a 30-fold range of larval densities at a standard resource abundance. We then compared fts of linear models and several diferent nonlinear models for the relationship of estimated rate of change and density. We fnd that that the relationship between density and per capita growth is strongly non-linear in Aedes aegypti (Linnaeus), Aedes albopictus (Skuse), and Aedes triseriatus (Say) mosquitoes. Components of population growth (survivorship, development time, adult size) are also nonlinearly related to initial density. The causes and consequences of this nonlinearity are likely to be important issues for population and community ecology
Experimental Optimization of a Free-to-Rotate Wing for Small UAS
This paper discusses an experimental investigation conducted to optimize a free-to-rotate wing for use on a small unmanned aircraft system (UAS). Although free-to-rotate wings have been used for decades on various small UAS and small manned aircraft, little is known about how to optimize these unusual wings for a specific application. The paper discusses some of the design rationale of the basic wing. In addition, three main parameters were selected for "optimization", wing camber, wing pivot location, and wing center of gravity (c.g.) location. A small apparatus was constructed to enable some simple experimental analysis of these parameters. A design-of-experiment series of tests were first conducted to discern which of the main optimization parameters were most likely to have the greatest impact on the outputs of interest, namely, some measure of "stability", some measure of the lift being generated at the neutral position, and how quickly the wing "recovers" from an upset. A second set of tests were conducted to develop a response-surface numerical representation of these outputs as functions of the three primary inputs. The response surface numerical representations are then used to develop an "optimum" within the trade space investigated. The results of the optimization are then tested experimentally to validate the predictions
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