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Assessing the Economic Impact of an Oil and Gas Firm’s Head Office Relocation to Calgary, AB

Huffman, John F
Fonte: Quens University Publicador: Quens University
Tipo: Relatório
EN
Relevância na Pesquisa
36.5%
Corporate head offices serve as the figureheads and decision-making cores of firms. For a variety of reasons, these head offices tend to locate in major cities. Cities themselves compete to attract head offices for their presumed positive economic impact, but what is the impact? Calgary, Alberta, is Canada’s energy centre and an emerging leader in head office counts that is expected to further grow its share of Canadian corporate head offices. This report seeks to estimate the economic impact of an oil and gas (O&G) firm relocating to Calgary, AB. Based on decades of theory and using data from a variety of sources, two multipliers are calculated: the economic base multiplier and the H.C. Davis income multiplier. By applying these multipliers to data regarding head office employment and O&G industry wages, estimates of the employment and income effects of the relocation are found. The results emphasize the importance of both the O&G industry and attracting head offices to Calgary. Based on these conclusions, two key policy avenues are recommended to encourage further expansion of Calgary’s head office counts.

The effects of changing head position and posture on head tremor in individuals with essential tremor involving the head

Badke, Nicole Jacqueline
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
36.55%
Objective: To determine the effects of head position and of different postural control demands on head tremor measures in participants with essential tremor. Methods: Seventeen participants with essential tremor (ET) of the head and 17 control participants took part. Individuals held their heads in varying degrees of rotation, flexion, and extension. Subsequently, individuals sat and stood in different postures, incorporating different foot placements (feet apart and together), surfaces (solid and foam), and vision conditions (eyes open and closed). Neck muscle activity was recorded from three muscles bilaterally (trapezius, sternocleidomastoid, splenius capitis). Three-dimensional head and thorax positions were recorded using an Optotrak system, and head angular velocity with respect to thorax was calculated by differentiating tilt-twist angles. Fourier analysis was used to determine tremor power. Results: ET participants showed sharp peaks at their tremor frequency in spectral plots of kinematic data, whereas CN participants did not. Electromyography data was too noisy for frequency analysis. ET participants displayed increased tremor power in head positions 25° from neutral compared to neutral and positions 50° from neutral. Tremor power increased with increasing difficulty of posture for both participant groups. Removal of vision resulted in decreased tremor power in ET participants; power was significantly decreased in the easier postures...

INVESTIGATIONS INTO THE BIOMECHANICS OF HEAD-BOBBING PIGEONS

Kroker, ANDRES
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
36.57%
Walking pigeons display a characteristic behaviour: head-bobbing. Head-bobbing consists of two phases, the hold phase during which the head is kept stable in space, and the thrust phase during which the head is quickly moved forward. But why do pigeons and so many other birds head-bob? Two theories have been developed to answer this question. First, head-bobbing may have a visual function, namely object detection during the hold phase and depth perception during the thrust phase. Second, head-bobbing may have the biomechanical function of increasing the stability. The present study aimed to gain further insight into why pigeons head-bob. A gait cycle analysis of walking pigeons revealed that the hold phase starts at a specific point in the gait cycle and is not dependent on the walking speed. The point in the gait cycle at which the hold phase starts indicates a potential increase in stability during the single stance phase, as it leads to a longer period of time during which the center of mass is above the base of support. The end of the hold phase, however, is dependent on the walking speed, specifically the step length for a given walking speed. I found that the thrust phase duration is constant for all walking speeds and the distance the head travels during that time is equal to the step length. With increasing walking speed the head moves faster during the thrust phase and the hold phase duration is decreased leading to a higher head-bobbing frequency. With fast enough walking speed the hold phase is eventually eliminated...