Optical tracking telescope compensation

In order to minimize the effects of parameter variations in the dynamics of an optical tracking telescope, a model referenced parameter adaptive control system is described that - in conjunction with more traditional forms of compensation - achieves a reduction of rms pointing error by more than a factor of six. The adaptive compensation system utilizes open loop compensation, closed loop compensation, and model reference compensation to provide the precise input to force telescope axis velocity to follow the ideal velocity

An evaluation of pump-level service as a locational variable within Canada\u27s retail gasoline industry

Marketers who are searching for prime retail locations for gasoline outlets, and other automobile-oriented activities, in today’s market are faced with an increasingly complex process. As land and development costs escalate, competition increases and margins are tightened, there is a greater need for marketers within the retail gasoline industry to pinpoint sites that offer the best profit potential (Gilbart, 1994). In turn, large gasoline chains attempt to develop networks of stations that optimize market coverage and consumer convenience while minimizing costs. In response to the evolution of an increasingly dynamic marketplace, experts within the retail gasoline industry have invested a great deal of time and money researching the key factors for station success. Traditional location analysis has involved the use of variables such as traffic volume and the number of trade area households to evaluate locations within the marketplace. While such variables are still essential, modern marketers must now consider a much wider range of locational factors which affect the success or failure of individual sites and/or aggregate networks

The primitive mystique : romance and realism in the depiction of the native Indian in English-Canadian fiction

Although several critics since the nineteenth century have written about the variety of interpretations of the native Indian in English-Canadian literature, no one has yet devoted a full-length study to the way the Indian is depicted in fiction alone. This dissertation thus examines a large cross-section of adult long fiction and investigates the degree to which the modes of romance and realism and the genres of romance and novel have informed these depictions. The dissertation is organized according to four major topics: love, religion, fighting, and community life. Each of these is divided into appropriate sub-topics, organized along roughly chronological lines. The chapter about love is the longest and focuses on fiction in which a white person and an Indian marry or have a love relationship, either potential or consummated. The chapter about religion focuses on fiction about the various kinds of relationships between native religions and Christianity. The chapter about fighting analyzes fiction about inter-tribal fighting, fighting along the frontier, and fighting between modern Indians and white authority. The chapter on community life focuses on fiction describing daily Indian life, from the pre-contact community to the contemporary reserve. Several conclusions emerge. First, the basic attitude to Indians reflects prevailing social attitudes. Second, the choice and use of genre are influenced to a significant degree by literary fashion. But more specific conclusions also emerge. Most importantly, romance is the dominant genre and romantic conventions of primitivism pervade almost all serious fiction on the subject, from variations on the Pastoral and Noble Savage conventions to a recent development approaching fertility myth. Instances of the realistic-novel as such are relatively rare, but realism of a documentary sort is frequent in romances which focus on social issues and is present for verisimilitude or ornamentation in many other romances. Finally,the best romances tend to have a sound basis in observable fact, just as the good novels have the subjective psychological dimension provided by romantic convention

Adapting Numerical Models of Surface Barrier Discharges to Real-World Conditions

The work described here aims to advance the numerical modelling used for Surface Barrier Discharges (SBDs) so that their design takes into account the non-idealised conditions encountered in real life. Starting from a two-dimensional fluid model of an SBD describing a single discharge gap, the model was used to analyse the effect of varying humidity on the species generated in the discharge. Furthermore, the model was upgraded to take into account heat transfer processes induced by the plasma, in addition to the mutual interaction between multiple discharge gaps when they are placed closely together. Wherever possible, the predictions of the model were compared to experimental data. For any application of SBDs where ambient air is the working gas, humidity varies at different times of the day and during different seasons. Therefore, it is vital to understand how the variation in humidity affects the generation of Reactive Oxygen and Nitrogen species (RONS). This motivated the first investigation in this work, in which the humidity level was used as an input to the model and the behaviour of the resultant species was analysed as a function of humidity. It is reported that the densities of HNOx species increase as humidity is increased, with the rate of increase slowing at higher humidity. Hydrogen-free species were only marginally influenced by humidity. These findings indicate that for applications where Hydrogen-free species are key, varying humidity from day to day is not a concern. For applications where HNOx species are important, the application should use synthetic air with a controllable added H2O fraction to maintain a steady dose of reactive species. A second observation on the operation of SBDs in ambient air is the rapid rise in their temperature. Considering that many reaction coefficients are functions of gas temperature, it is vital to understand how the increase in gas temperature impacts the performance of the SBD as a source of reactive species. This motivated a key development made in this work which was incorporating heat transfer treatment into the SBD model. This was achieved by coupling the heat equation to the model. Two sources of heat were computed: the heat flux to the dielectric surface due to ion bombardment and the volumetric heat source in the gas due to inelastic collisions between the background gas and energetic electrons. The work revealed that ion bombardment was the primary heating mechanism of the dielectric. The impact of accounting for the increase in temperature was also investigated, where it was shown that it can cause a difference of up to 40% in the densities of some species, particularly the Reactive Nitrogen species (RNS). The impact of this finding is that it paves the way for controlling the long-lived species chemistry of the discharge by controlling the temperature of the dielectric. Consequently, for a practical application where Reactive Oxygen Species (ROS) are of interest, active cooling of the dielectric is recommended, while for an application focused on RNS, active heating of the dielectric is advantageous. Another impact of this investigation was quantifying the errors in species density predictions from numerical models describing SBDs when the temperature effect is ignored, which were up to 40%. The third aspect of SBDs applications investigated was the use of an SBD array, consisting of closely spaced discharge gaps, instead of a single discharge gap configuration as is typically used for research studies. The proximity of discharge gaps may induce emergent phenomena which cannot be observed in a single discharge. To capture such phenomena, the model was upgraded to investigate an array of 6 discharge gaps with a controllable distance between them. Supporting evidence was provided by Particle Image Velocimetry (PIV) experimental data. It was shown in this work that increasing the electrode width resulted in the discharge power decreasing exponentially for a fixed applied voltage. It was also shown that decreasing the distance between the discharge gaps forced flow vortices to overlap, creating a ripple in the flow downstream of the discharge, where the velocity varies by 200% from maximum to minimum value. This ripple has a significant impact on the flux of species to a downstream sample when the flux is convection dominated. These findings show that while bringing the sample to be treated closer to the SBD array increases the flux to it as it is convection dominated, it comes at the expense of uniformity. Thus, a trade-off must be made between the magnitude of the arriving flux to a sample and its uniformity. Briefly, the work presented in this thesis provides a set of recommendations to be considered when designing an SBD for a particular application. The work described here aims to advance the numerical modelling used for Surface Barrier Discharges (SBDs) so that their design takes into account the non-idealised conditions encountered in real life. Starting from a two-dimensional fluid model of an SBD describing a single discharge gap, the model was used to analyse the effect of varying humidity on the species generated in the discharge. Furthermore, the model was upgraded to take into account heat transfer processes induced by the plasma, in addition to the mutual interaction between multiple discharge gaps when they are placed closely together. Wherever possible, the predictions of the model were compared to experimental data. For any application of SBDs where ambient air is the working gas, humidity varies at different times of the day and during different seasons. Therefore, it is vital to understand how the variation in humidity affects the generation of Reactive Oxygen and Nitrogen species (RONS). This motivated the first investigation in this work, in which the humidity level was used as an input to the model and the behaviour of the resultant species was analysed as a function of humidity. It is reported that the densities of HNOx species increase as humidity is increased, with the rate of increase slowing at higher humidity. Hydrogen-free species were only marginally influenced by humidity. These findings indicate that for applications where Hydrogen-free species are key, varying humidity from day to day is not a concern. For applications where HNOx species are important, the application should use synthetic air with a controllable added H2O fraction to maintain a steady dose of reactive species. A second observation on the operation of SBDs in ambient air is the rapid rise in their temperature. Considering that many reaction coefficients are functions of gas temperature, it is vital to understand how the increase in gas temperature impacts the performance of the SBD as a source of reactive species. This motivated a key development made in this work which was incorporating heat transfer treatment into the SBD model. This was achieved by coupling the heat equation to the model. Two sources of heat were computed: the heat flux to the dielectric surface due to ion bombardment and the volumetric heat source in the gas due to inelastic collisions between the background gas and energetic electrons. The work revealed that ion bombardment was the primary heating mechanism of the dielectric. The impact of accounting for the increase in temperature was also investigated, where it was shown that it can cause a difference of up to 40% in the densities of some species, particularly the Reactive Nitrogen species (RNS). The impact of this finding is that it paves the way for controlling the long-lived species chemistry of the discharge by controlling the temperature of the dielectric. Consequently, for a practical application where Reactive Oxygen Species (ROS) are of interest, active cooling of the dielectric is recommended, while for an application focused on RNS, active heating of the dielectric is advantageous. Another impact of this investigation was quantifying the errors in species density predictions from numerical models describing SBDs when the temperature effect is ignored, which were up to 40%. The third aspect of SBDs applications investigated was the use of an SBD array, consisting of closely spaced discharge gaps, instead of a single discharge gap configuration as is typically used for research studies. The proximity of discharge gaps may induce emergent phenomena which cannot be observed in a single discharge. To capture such phenomena, the model was upgraded to investigate an array of 6 discharge gaps with a controllable distance between them. Supporting evidence was provided by Particle Image Velocimetry (PIV) experimental data. It was shown in this work that increasing the electrode width resulted in the discharge power decreasing exponentially for a fixed applied voltage. It was also shown that decreasing the distance between the discharge gaps forced flow vortices to overlap, creating a ripple in the flow downstream of the discharge, where the velocity varies by 200% from maximum to minimum value. This ripple has a significant impact on the flux of species to a downstream sample when the flux is convection dominated. These findings show that while bringing the sample to be treated closer to the SBD array increases the flux to it as it is convection dominated, it comes at the expense of uniformity. Thus, a trade-off must be made between the magnitude of the arriving flux to a sample and its uniformity. Briefly, the work presented in this thesis provides a set of recommendations to be considered when designing an SBD for a particular application

Non-purulent low-grade infection as cause of pain following shoulder surgery: preliminary results

Low-grade infection was systematically searched for in all revision shoulder surgeries by harvesting tissue samples. Ten consecutive patients were identified with a non-purulent low-grade infection of the shoulder. All of these patients suffered from pain and eight were stiff. Preoperative aspiration in eight patients yielded bacterial growth in only one case. Serum C-reactive protein levels were normal in seven out of 10 cases. Propionibacterium acnes was identified in seven, coagulase-negative Staphylococcus in two and Staphylococcus saccharolyticus in one case. The delay between harvesting the tissue samples and detection of bacterial growth averaged eight days (range, 2-17). After debridement and antibiotic treatment for a mean of 4.5 months, tissue samples were repeatedly harvested in nine patients due to persistent pain. The infection was microbiologically eradicated in six out of nine cases that had a repeated biopsy. However, nine out of 10 patients continued to suffer from moderate to severe pain. Low-grade infection of the shoulder can be a cause of persistent pain and stiffness. The results of antibiotic treatment are disappointing. Further studies are necessary to analyse this difficult patholog

Facteurs et modalités d’insertion des activités productives entre tissus urbains et parcs d’activité économique

À la croisée des enjeux de réindustrialisation et de sobriété foncière, cet article questionne les pratiques d’aménagement économique par le prisme des facteurs et modalités d’insertion des activités productives au sein des tissus urbains et des parcs d’activité économique. Comment une volonté régionale de réindustrialisation se traduit-elle localement ? Si la question de la réindustrialisation dans les villes petites et moyennes est indissociable d’une meilleure compréhension de l’écosystème entrepreneurial local, d’une part, et d’une meilleure intégration de la fonction productive dans les politiques d’aménagement urbain, d’autre part, quelles sont les dynamiques relationnelles qu’entretiennent la production et le territoire ? Cette étude, réalisée sur les territoires post-miniers de Mons-Borinage, localisés en Belgique, aborde ces questionnements en trois temps : d’abord par la mise en contexte du territoire ; ensuite par la mise en lumière d’une étude empirique menée auprès de 10 TPE-PE productives, abordée par le prisme de l’entrepreneur ; et enfin par la mise en perspective de ces résultats en confrontant les pratiques d’aménagements économique aux objectifs de sobriété foncière.At the crossroads of the issues of reindustrialization and land sobriety, this article questions the practices of economic development through the methods of inserting productive activities within urban fabrics and economic activity parks. How does a regional desire for reindustrialization translate locally? If the question of reindustrialization in small and medium-sized towns is inseparable from a better understanding of the local entrepreneurial ecosystem, on the one hand, and from a better integration of the productive function in urban planning policies, on the other hand, what are the relational dynamics between production and territory? This study, carried out on the post-mining territories of Mons-Borinage, located in Belgium, addresses these questions in three stages: first by putting the territory into context, then by highlighting an empirical study carried out with 10 productive VSEs-PEs, imagined through the prism of the entrepreneur, and finally by putting these results into perspective by confronting the practices of economic development with the objectives of land sobriety

A qualitative study of attitudes towards, typologies, and drivers of concurrent partnerships among people of black Caribbean ethnicity in England and their implications for STI prevention.

BACKGROUND: Partner concurrency, (having sexual partnerships overlapping in time), especially when condoms are not used, can facilitate sexually transmitted infections (STI) transmission. In Britain, STI diagnoses rates and the reporting of concurrency are higher among black Caribbeans than other ethnic groups. We explored attitudes towards, drivers, characteristics, and contexts of concurrent partnerships, and their implications for STI risk among black Caribbeans in England. METHODS: Purposive sampling, by sex and age-groups, was used to recruit participants (overall n = 59) from five sexual health clinics and community settings in London and Birmingham, England. Audio-recorded four focus group discussions (n = 28 participants), and in-depth interviews (n = 31) were conducted (June 2014-December 2015). Transcribed data were thematically analysed using Framework Analysis. RESULTS: 'Main plus' and 'non-main' concurrency were identified in this population. Main plus concurrency involves an individual having a main partner with whom s/he has a "relationship" with, and the individual and/or their partner secretly or explicitly have other non-main partners. In contrast, non-main concurrency entails having multiple, non-committed partners overlapping in time, where concurrency is usually taken as a given, making disclosure to partners irrelevant. While main partnerships were usually long-term, non-main partnerships ranged in duration from a single event through to encounters lasting several months/years. Condomless sex was common with ex/long-term/married/cohabiting partners; whereas condoms were typically used with non-main partners. However, condom use declined with partnership duration and familiarity with partners. Awareness of partners' concurrency facilitated condom use, STI-testing, and partner notification. While unresolved feelings, or sharing children with ex-partners, usually facilitated main plus concurrency; non-main concurrency was common among young, and single people. Gender norms, notions of masculinity, and sexual desires influenced concurrency. Black Caribbean popular music, social media, peer pressure, and relationship norms among black Caribbeans were also perceived to encourage concurrency, especially among men and young people. CONCLUSIONS: Concurrency among black Caribbeans is shaped by a complex interaction between emotional/psychological, interpersonal, sociocultural, and structural factors. Concurrency type, its duration, and awareness influence sexual health choices, and thus STI risk in this population. Collecting these data during clinic consultations could facilitate offering partner notification methods tailored to concurrency type. Gender- and age-specific, culturally-sensitive interventions addressing STI risks associated with concurrency are needed

Spacelike surfaces with free boundary in the Lorentz-Minkowski space

We investigate a variational problem in the Lorentz-Minkowski space \l^3 whose critical points are spacelike surfaces with constant mean curvature and making constant contact angle with a given support surface along its common boundary. We show that if the support surface is a pseudosphere, then the surface is a planar disc or a hyperbolic cap. We also study the problem of spacelike hypersurfaces with free boundary in the higher dimensional Lorentz-Minkowski space \l^{n+1}.Comment: 16 pages. Accepted in Classical and Quantum Gravit