A case study of student projects for industry clients

Published versio

Examining the Development Effects of Modern-Era Streetcars: An Assessment of Portland and Seattle

Most U.S. cities pursuing streetcars are doing so primarily for their purported development effects, as opposed to for their transportation role, yet there is little evidence about the nature or magnitude of these development effects due to a scarcity of rigorous, empirical research. Most available work simply presents descriptive information about development outcomes (typically measured as changes in population, employment, land values, or permit activity) within streetcar corridors as indicators of the streetcar’s development effects. Alternate factors which may have influenced such results are often not considered, placing into question the validity of such measures.This study examines the development effects of streetcar investments in two U.S. cities that implemented streetcar service between 2000 and 2010: Portland, Oregon, and Seattle, Washington. The authors explore the development outcomes (here measured as the number of permits issued) through a combination of statistical analysis of development activity in the streetcar corridor and interviews with key streetcar stakeholders. The statistical results indicate that areas around Portland’s initial streetcar line experienced higher levels of development activity (more permits issued) than areas not served by the streetcar, although the differences in activity between served and not served areas since the opening of the second line have been insignificant. In Seattle, the areas around the streetcar line in the South Lake Union neighborhood experienced greater commercial development activity (commercial permits issued) but less residential activity than nearby unserved areas. The interviews provide important local context for the interpretation of the empirical results and highlight the continued importance of development as a rationale for streetcar investments, as well as to the limitations of the streetcar as a transportation service

The sign rule and beyond: Boundary effects, flexibility, and noise correlations in neural population codes

Over repeat presentations of the same stimulus, sensory neurons show variable responses. This "noise" is typically correlated between pairs of cells, and a question with rich history in neuroscience is how these noise correlations impact the population's ability to encode the stimulus. Here, we consider a very general setting for population coding, investigating how information varies as a function of noise correlations, with all other aspects of the problem - neural tuning curves, etc. - held fixed. This work yields unifying insights into the role of noise correlations. These are summarized in the form of theorems, and illustrated with numerical examples involving neurons with diverse tuning curves. Our main contributions are as follows. (1) We generalize previous results to prove a sign rule (SR) - if noise correlations between pairs of neurons have opposite signs vs. their signal correlations, then coding performance will improve compared to the independent case. This holds for three different metrics of coding performance, and for arbitrary tuning curves and levels of heterogeneity. This generality is true for our other results as well. (2) As also pointed out in the literature, the SR does not provide a necessary condition for good coding. We show that a diverse set of correlation structures can improve coding. Many of these violate the SR, as do experimentally observed correlations. There is structure to this diversity: we prove that the optimal correlation structures must lie on boundaries of the possible set of noise correlations. (3) We provide a novel set of necessary and sufficient conditions, under which the coding performance (in the presence of noise) will be as good as it would be if there were no noise present at all.Comment: 41 pages, 5 figure

Glass fibre reinforced polymer bars in concrete compression members

The use of Glass Fibre-Reinforced Polymer (GFRP) composite materials as reinforcement for concrete structures to overcome corrosion problems has been growing. Past Canadian applications are dominated by bridge decks and car parks where de-icing salts are used. Other applications include coastal structures and structures aiming for improved durability. Our research aimed to examine the practicality of using GFRP bars as reinforcement in concrete compression members. Twenty-four concrete columns reinforced with either steel or GFRP were loaded in compression until failure, with ultimate compressive strengths and horizontal displacements of the bars recorded. The results indicate that the use of GFRP bars as reinforcement in concrete compression members is technically viable, with GFRP reinforced columns yielding almost the same capacity as those reinforced with equal areas of steel. Incorporation of extra GFRP stirrups was found to improve the capacity in bending of the longitudinal GFRP reinforcement. Cost comparisons have also been completed to ensure the use of GFRP reinforcement is economically viable. The research concluded that reinforcing concrete columns with GFRP bars is an attractive option when life span and/or durability are of high priority. The research was followed by the first design and construction of reinforced concrete compression members utilising GFRP in Australia. This was done at the Dundas Point Boardwalk on the Swan River in Applecross, Western Australia, completed in 2014. Ongoing research will initiate in 2015 at UWA to investigate GFRP subject to combined bending and axial stressing

Assessing the Performance of the Diffusion Monte Carlo Method as Applied to the Water Monomer, Dimer, and Hexamer

The Diffusion Monte Carlo (DMC) method is applied to the water monomer, dimer, and hexamer, using q-TIP4P/F, one of the most simple, empirical water models with flexible monomers. The bias in the time step ($\Delta\tau$) and population size ($N_w$) is investigated. For the binding energies, the bias in $\Delta\tau$ cancels nearly completely, while a noticeable bias in $N_w$ still remains. However, for the isotope shift, (e.g, in the dimer binding energies between (H$_2$O)$_2$ and (D$_2$O)$_2$) the systematic errors in $N_w$ do cancel. Consequently, very accurate results for the latter (within $\sim 0.01$ kcal/mol) are obtained with relatively moderate numerical effort ($N_w\sim 10^3$). For the water hexamer and its (D$_2$O)$_6$ isotopomer the DMC results as a function of $N_w$ are examined for the cage and prism isomers. For a given isomer, the issue of the walker population leaking out of the corresponding basin of attraction is addressed by using appropriate geometric constraints. The population size bias for the hexamer is more severe, and in order to maintain accuracy similar to that of the dimer, the population size $N_w$ must be increased by about two orders of magnitude. Fortunately, when the energy difference between cage and prism is taken, the biases cancel, thereby reducing the systematic errors to within $\sim 0.01$ kcal/mol when using a population of $N_w=4.8\times 10^5$ walkers. Consequently, a very accurate result for the isotope shift is also obtained. Notably, both the quantum and the isotope effects for the prism-cage energy difference are small.Comment: 11 pages, 5 figures, 36 references. Submitted to the Journal of Physical Chemistr

Characteristics and management practices of selected Jamaican broiler growers in 1977-78

The purpose of this survey-type study was to (1) investigate the characteristics of three sizes of broiler operations under contract in : Jamaica in 1978, (2) to determine which of 16 recommended broiler management practices were being used and which were not being used by growers, and (3) to consider influences at work as broiler growers decided whether or not to use the recommended practices. A 10% random sample of 43 Jamaican broiler growers under contract in 1978 was randomly selected and interviewed. House capacity for growers in the study ranged from 6,000 to 42,000 birds. Large growers had grow-out capacities ranging from 15,000 to 42,000 birds, medium growers from 10,000 to 12,000, and small growers, 6,000 birds. All 43 growers in the study were full-time broiler growers, and nearly all, 95%, listed broiler growing as their main source of agricultural income. The average broiler grower had been in operation for 6.4 years and had two broiler houses on their farms, averaging 6.6 years old. All but one grower used gas brooders, and their broiler houses were ventilated by the sea breeze. Most growers, 86%, used pan feeders and changed litter after every grow-out. Most growers studied, 91%, used public water supply for their birds and reported little difference in the number of grow-outs per year, the average being 3.6. There was little difference noted also in number of days between graw-outs for all growers, the average being 22.8 days. All growers studied were found to be using all 16 management practices studied and seemed to have been most influenced by the broiler growing contract with their company. Most growers, 70%, planned to expand by building new broiler houses, and most, 56%, said they planned to use the Jamaica Development Bank (J.D.B.) as their main credit source. All were interested in learning more about management, housing, and their contract. Management, housing, and understanding of the contract agreement were work areas identified in this study where growers would like appropriate help from the Jamaica Extension Service

Irrigators\u27 Vulnerability to Drought in the Flathead River Basin, Montana

Irrigation has traditionally been used to buffer the effects of drought in agricultural communities. However, drought events can still lead to drought damage for irrigators by reducing irrigation water supplies, increasing crop water demand, and creating habitats for invasive pests and weeds. Further, drought will be increasingly problematic in irrigated areas as climate change continues to affect global climates and water resources. The Flathead River basin contains substantial areas of irrigated agriculture including the 128,000 acre Flathead Irrigation Project (FIP). The FIP is the largest irrigation project in Montana as well as the largest of the 16 Bureau of Indian Affairs (BIA) federal irrigation projects. This thesis explores the drought experiences of irrigators in the Flathead River basin using a case study approach. Eighteen semi-structured interviews were conducted with irrigators in the basin and then analyzed using content analysis. Themes from this analysis were then explored in order to understand how irrigators are vulnerable to drought. Findings show that drought for irrigators in the Flathead River basin is a complex phenomenon. It is physically constructed of processes affecting both long-term water availability and short-term growing season dryness. Additionally, institutional arrangements affecting water management and the economic marginalization of the agriculturalist lifestyle have led to drought vulnerabilities for some irrigators in the basin. These findings illustrate how the political economy of irrigation and agriculture are contributing to drought impacts and drought hazard in the Flathead River basin