Faculty of Graduate Studies

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Open Access
French-Canadian newspapers and imperial defence 1809-1914
(York University, 1967) Laxer, James
Open Access
A Collection and Re-creation of Bahamian Traditional Dances
(1992-10-01) Johnson, Roderick Theophilus
This research project provides a collection and re-creation of eleven traditional Bahamian dances. Since the early eighteenth century,Bahamian folk dancing has been an integral part of the native's social life and culture and has been heavily influenced by three cultural groups: African, American and British. People from these three cultures were the first immigrants to the island and their folk dances form the underlying structural base of the Bahamian folk dance tradition. Eventually these cultural elements were synthesised into a distinctive Bahamian folk style. In comparison to the amount of traditional dance information available from other Caribbean countries, the documentation on Bahamian folk dance tradition is sketchy at best. Adding to the lack of documentation is a continued decline in the spontaneous practice and cultural performances of these dances, plus little or no regular instruction to allow for the dances' survival in the culture. A sad consequence of cultural change is the loss or distortion of folk art. This is the present condition of the majority of traditional Bahamian folk dances. New trends in music as well as increased urbanization are causing many Bahamians to ignore or abandon their culture and heritage and as a result the dances which were once an important part of Bahamian society are now dying out. The awareness of the present condition of the dances has given me the necessary incentive to study ,examine and document the Bahamian Folk dance tradition. Central to this research project are two documentary video tape recordings of the Bahamian traditional dances. These tapes provide: necessary historical background,a step by step introduction to Bahamian dance, and important clues to the origins of them. The first tape explores the social,historical and cultural framework from which the Bahamian traditional dances have evolved. The second tape continues with a careful examination and documentation of each of the dances that will enable the viewer to actually recreate them and thus gain an even deeper understanding of the Bahamian folk style. I chose to use the medium of video through which to present my research because of its ability to capture the dances in a way that writing could not. Recording the dances on video allowed for the documentation of each dance as a whole entity in that the mannerisms, gestures, behaviour and steps were simultaneously recorded and preserved. As each dance has experienced a continued erosion of tradition at the hands of progress and increased modernization of the Bahamas,the video format has allowed me to record and thus preserve each dance before it is lost entirely.
Open Access
Corporate law, pension law and the transformative potential of pension fund investment activism
(2002-07) Kodar, Freya; Condon, Mary
Pension funds, the funds held in trust to support occupational pension plans, represent significant funds of capital. Together with other institutional investors such as mutual funds and hedge funds they have become important actors in financial markets - nationally and internationally. They have significant holdings in national and transnational corporations. They are also deeply implicated in the financial instability of global financial markets, and free market globalization. In the past decade some members of the labour movement have sought to have more active involvement in pension fund investment decision-making. They have seen this involvement as a strategy for influencing corporate management and practice, and for encouraging productivity, local and regional development and long-term growth and sustainability. More radically, they have seen it as a means to create new conceptions of ''value" that include factors other than monetary return, and to transform capital by gaining greater social and democratic control over it. They have pursued strategies such as advocating for greater representation on pension plan boards of trustees or investment advisory committees, shareholder activism including proxy voting, investment screening and economically targeted or community investing. This thesis assesses these strategies within the Canadian context and looks at their transformative potential in light of pension law and corporate law principles and practice. It argues that the current strategies of pension fund activists, even if extended to other types of investors - individuals and institutional - are not likely to lead to more democratic and social systems of corporate regulation. It also suggests that pension fund activists have not fully explored the possibilities created by the fact that pension funds have many ''owners" and "beneficiaries" - legal or otherwise. Nor have their strategies adequately considered the suggestion that the uncertainties of corporate law make completing the separation of the corporation from the shareholder, and creating democratic and social systems of corporate regulation, a more appropriate and meaningful political project. In short, they have not challenged the limitations of pension law and corporate law with strategies that recognize the corporation and markets as social institutions that should be democratically and socially regulated. One avenue for doing this appears to be through utilizing the public pension system, particularly by expanding a funded public pension system, and democratizing the fund investment decision-making process.
Open Access
The significance of corporeal factors and choreographic rhythms in Jamaican popular music between 1957--1981 (Ska, Rocksteady, Reggae), with an historical and critical survey of all relevant literature dealing with Jamaican folk, religious and popular musics and dance
(York University, 2007) McCarthy, Leonard Joseph
Most studies of Jamaican Popular Music (JPM)--Ska, Rocksteady, Reggae--only discuss sonic structures as isolated phenomena, with little consideration of correlationships between JPM sonic patterns and those of indigenous Jamaican Folk and Religious Music (JFRM). Most also pay insufficient attention to the role of corporeality in the characteristics, development and performance practices of Jamaican music. This study is in two parts. (1) An historical and critical survey of all relevant literature dealing with JPM and JFRM which examines the applicability of this work to this study's thesis, with new concepts and theories introduced where appropriate. A compendium structure organizes information by historical influences, genre, musicological characteristics, movement orientations and theoretical concerns, with comprehensive citations for each subsection. (2) Part Two consists of original musicological and movement analysis of 878 video performances by 299 JPM and JFRM artists. This research identifies particular couplings of sound and movement patterns, which Agawu (2003) calls choreographic rhythms (CRs). From these findings, this study's thesis emerges in four main points: (1) JPM and JFRM performers share similar, uniquely Jamaican CRs, which appear to account for the idiosyncratic rhythmic feel of most Jamaican music. (2) Jamaican CRs are rooted in neo-African musical traditions, which are themselves rooted in West and Central African musics.(3) Jamaican musical traditions are transmitted/acquired primarily via mimesis. (4) Enactivist research 1 about music perception/cognition and cultural environments explains how growing up in particular cultures develops CRs which shape the musical understanding and performance practices of people within cultural communities. This research explains why people have difficulty perceiving and executing foreign CRs because they intuitively utilize their own indigenous CRs instead. By integrating the material surveyed in Part One with the findings in Part Two, it is concluded that proper understanding Jamaican music requires consideration of corporeal, sonic and other cultural factors as gestalt unities. It follows that this approach could benefit the study of any music. The final chapter features a concordance of topics and themes examined in the entire study which functions as an index. 1 Enactivism is a branch of cognitive science which has emerged since the early 1990s.
Open Access
The stylistic diversity of the concert saxophone
(York University, 2007-07) Rubinoff, Daniel I.
This thesis examines the sonic parameters and musical versatility of the concert saxophone. Invented in 1840, the instrument failed to become a regular member of the symphony orchestra, and is thus underrepresented in classical music. This researcher argues that the saxophone's unique sonic design makes it an effective contemporary instrument in a wide variety of genres. Specifically, the techniques of subtone, harmonics, and false fingerings are examined from both a performance and compositional perspective. Additionally, the instrument's resemblance to the human voice is documented. An examination of five original saxophone compositions highlights the instrument's flexibility as a solo instrument or as a member of an ensemble. This work adds to the number of original compositions for the saxophone and explores the reasons behind the instrument's success in contemporary music.
Open Access
Cuban Piano Music: Contradanza
(2009-10-21) del Monte-Escalante, Glenda
This work is based on research, analysis, studies and performance of Cuban concert piano music. The aim of the paper is to illustrate the historical development of this music from the 19th Century repertoire of contradanzas. This project will involve a paper in support of a recital. It is of great interest to me as a pianist, composer, educator and researcher to promote awareness of such an important part of Cuban music culture, its piano music repertoire and some of its most central composers. This repertoire represents a continuous tradition of Cuban Piano Music dating from the early nineteenth century. It has its origins in England, Spain and France, while its rhythm and syncopated style derive from Africa. In 1871 French colonists were fleeing from Haiti’s slave rebellion. When these Haitians arrived in Cuba they also brought their cultural traditions, in particular the Contredanse. Typical of this music is its consistent binary approach to form and its variously modified tango (“habanera”) rhythm. This rhythm is notated in at least three different ways, which suggests that there is more than one way to express the buoyancy or special lift so essential to this music. Generally, this repertoire has been considered to underlie both classical and popular music in Cuba and to have significantly influenced other music outside of Cuba as well. Given its roots in Spanish musical folklore and its general use of African rhythms, Cuban piano music is an important part of the music history of Cuba. However, it has been relatively neglected by historians, especially in the English language. These Cuban danzas are the source of the rhythm known as Habanera, and they are a result of the fusion of wide and various musical traditions which led to the development of a national expression and “Cuban” identity.
Open Access
Multiple acts of birding: the Education, ethics and ontology of bird watching in Ontario
(2010-12-08T02:56:06Z) Watson, Gavan Peter Longley
While bird watching has captured the attention of those interested in fostering an experiential connection to the more-than-human, research conducted to date often assumes birding to be a heterogeneous act. As an example of free-choice learning, this work positions birding as a kind of environmental education, thus opening this popular activity to analysis missing from the literature thus far. Rather than a singular act, this investigation sees birding as a multiple, ontological object. As a result, the practices of field birding, backyard birding and bird rescue were studied with the goal of describing the relationship between practices and birders’ perspectives of and relationships with wild birds. Influenced by actor-network theory, a method assemblage was developed using multiple sources of data, including: semi-structured interviews analysed using a modified grounded theory approach; field journals analysed with a naturalist autoethnography lens; and photographs analysed using a spatially and personally contextualized approach. This research shows that birding often starts with a curious person observing a bird’s presence and then trying to identify the species. While awareness and knowledge of natural phenomena can assist in the identification of a bird, when the observation of an individual becomes a record of a species the act of identification marks a reductive moment between birders and birds. Ornithology, technology and birding are deeply intertwined. Yet, their influence on practice often goes unrecognized. In the emergent move to digital objects in birding, images, rather than birds, risk becoming the epistemological object. The influence of place on the construction of birds’ visibility and value is investigated. As a result of the lens of home place, birds in the backyard are rendered differently than in the field, with some included in backyard birder’s social sphere. Bird rescuers enact yet another relationship with birds, one where care is the primary concern and a focus on identification to species falls to the periphery. Ultimately, as a counter to instrumental and anthropocentric constructions of nature fostered by certain enactments of birding, reflexive birding is offered as an example of practice, which promises to foster awareness of birders’ connections to the deeply material lives of birds.
Open Access
A Close Look at the Hydrolytic Mechanism of OXA-58, a Class D β-Lactamase from Acinetobacter baumannii
(2012-04-25) Amini, Kaveh
OXA-58 enzyme from Acinetobacter baumannii is a carbepenm-hydrolyzing class-D β-lactamase which uses a carbamylated lysine to activate the nucleophilic serine used for β-lactam hydrolysis. The deacylating water molecule approaches the acylenzyme intermediate formed between the enzyme and the β-lactam from the α-face. According to our findings, OXA-58 uses the same catalytic machinery observed in class D β-lactamases such as OXA-10. Comparison of active site shape in OXA-58, OXA-24 and OXA-48 with the OXA-10 β-lactamase suggests that these carbapenem-hydrolyzing class D β-lactamases have gained the capability of hydrolyzing imipenem, an important carbapenem in clinical use, by slight structural changes in the active site. Also, investigation of the kinetics of β-lactam hydrolysis by Phen113A, Phen114A, Met225A, Phen113Tyr, Phen114l1e and Met225Thr shows that penicillin G is hydrolyzed better than amoxicillin and ampicillin which are hydrolyzed with comparable catalytic efficiencies. Carbenicillin was the poorest substrate.
Open Access
Mesoscale Boundaries and Storm Development in Southwestern Ontario During Elbow 2001
(2012-10) Alexander, Lisa Susan; Taylor, Peter
The Effects of Lake Breezes on Weather (ELBOW) 2001 project was conducted in Southwestern Ontario, during summer 2001. Project goals included: understanding how lake breezes interact with one another, other mesoscale boundaries and synoptic fronts, understanding how lake breezes affect storm development, and helping to improve regional forecasts by transferring findings to forecasters. Radar, Satellite, Mesonet and Integrated (considering all data sets) analyses were each used to identify the mesoscale boundaries that occurred during the study period. A contingency table approach, for lake breeze occurrence, was used to evaluate each of the analyses against a Final 'Truth' Set. Findings showed that the Integrated analysis performed the best. Advantages and drawbacks of each analysis became apparent. Evaluation of the analyses was also done by studying the in land penetration distances of the lake breeze fronts. This revealed that most the analyses had good correlation to the Final 'Truth' Set. The Mesonet analysis was the least accurate for pinpointing lake breeze fronts, due to lack of information between surface stations. The boundary analysis showed that lake breeze fronts, originating from one or more of the surrounding lakes, occurred in the study area on 73 out of 86 days, or 85% of the days (for 1800 UTC). Exeter radar data (CAPPI and MAXR) were run through URP cell identification and tracking algorithms. The locations of storm cells, when they reached a 40 dBZ level, were measured relative to the closest boundary. Considering study days without warm front influence, 70.4% of the 40 dBZ CAPPI cell initiations and 68.5% of the 40 dBZ MAXR cell initiations occurred at a distance of 20 km or less from a boundary. Cell distribution plots were created to show the locations of the 40 dBZ cell initiations in front or behind a specified boundary type or boundary classification. Nowcasting techniques considering cumulus cloud development and Lifted Index values in the 'lifting zone' of the boundary, the convergence strength and updraft orientation along the boundary, and the boundary relative cell speed, were utilized in case studies. Reasons for the development, or the lack thereof, became apparent in cases presented.
Open Access
Generic on-board-computer hardware and software development for nanosatellite applications
(2012-11) Borschiov, Konstantin; Lee, Regina; Quine, Brendan
This study outlines the results obtained from the development of a generic nanosatellite on-board-computer (OBC). The nanosatellite OBC is a non-mission specific design and as such it must be adaptable to changing mission requirements in order to be suitable for varying nanosatellite missions. Focus is placed on the commercial-off-the-shelf (COTS) principle where commercial components are used and evaluated for their potential performance in nanosatellite applications. The OBC design is prototyped and subjected to tests to evaluate its performance and its feasibility to survive in space.
Open Access
Towards an Ontology and Canvas for Strongly Sustainable Business Models: A Systemic Design Science Exploration
(2013-09-13) Upward, Antony; Johnston, David
An ontology describing the constructs and their inter-relationships for business models has recently been built and evaluated: the Business Model Ontology (BMO). This ontology has been used to conceptually power a popular practitioner visual design tool: the Business Model Canvas (BMC). However, implicitly these works assume that designers of business models all have a singular normative goal: the creation of businesses that are financially profitable. These works perpetuate beliefs and businesses that do not create outcomes aligned with current natural and social science knowledge about long term individual human, societal and ecological flourishing, i.e. outcomes are not strongly sustainable. This limits the applicability and utility of these works. This exploratory research starts to overcome these limitations: creating knowledge of what is required of businesses for strongly sustainable outcomes to emerge and helping business model designers efficiently create high quality (reliable, consistent, effective) strongly sustainable business models. Based on criticism and review, this research project extends the BMO artefact to enable the description all the constructs and their inter-relationships related to a strongly sustainable business model. This results in the Strongly Sustainable Business Model Ontology (SSBMO). To help evaluate the SSBMO a practitioner visual design tool is also developed: the Strongly Sustainable Business Model Canvas (SSBMC). Ontological engineering (from Artificial Intelligence), Design Science and Systems Thinking methodological approaches were combined in a novel manner to create the Systemic Design Science approach used to build and evaluate the SSBMO. Comparative analysis, interviews and case study techniques were used to evaluate the utility of the designed artefacts. Formal 3rd party evaluation with 7 experts and 2 case study companies resulted in validation of the overall approaches used and the utility of the SSBMO. A number of opportunities for improvement, as well as areas for future work, are identified. This thesis includes a number of supplementary graphics included in separate (electronic) files. See “List of Supplementary Materials” for details.
Open Access
Critically Evaluating the Role of the Judiciary in the Good Governance Paradigm: A Study of Pakistan
(2014-06) Muhammad Azeem; Ruth M Buchanan
In this dissertation, I critically evaluate the central role assigned to the judiciary in “the good governance” paradigm (as promoted by international institutions such as the World Bank), through a study of Pakistan. I argue that the paradigm’s focus on institutional arrangements/rearrangements, in order to produce a strong judiciary, judicial reforms, and to implement ‘the rule of law’, is problematic. I find, in contrast, and based on a detailed historical study of the different judicial regimes in the post-colonial era, that the judiciary is a part of the state, and has served to reproduce the state, in its democratic and military forms, as well as political and structural inequality in Pakistan. I document in detail how the judiciary increasingly gained autonomy in state power leading to result in what I term as a ‘judicial dictatorship’ by the 2000s. Through the thesis, I advance an alternative structural analysis of the state and institutional arrangements, using a class analysis and historical-contextual approach. My study argues that a strong (‘activist’) judiciary cannot be a substitute for a weak and inadequately representative legislature. The fallback position of the judiciary - in promoting a ‘rights’ discourse, or protection of minorities - is also an inadequate remedy for the lack of a deeper democracy in the society. My research in Pakistan contributes to the view that the role of the judiciary ultimately is to uphold political ends crafted elsewhere, rather than be seen as an agent to ‘cause’ political betterment. This study is based on most of the relevant case law in the post-colonial era, primary sources such as interviews, speeches, and judge’s monographs, as well as the available secondary material such as journal articles, books, and newspaper reports.
Open Access
Buffalo Death Mask
(2014-07-09) Hoolboom, Mike; Schwartz, Judith
The thesis essay has arrived in six parts. It opens with a discussion of my method, and closes with a detailed look at Buffalo Death Mask, the short digital movie I made in 2013 about AIDS. In between are a pair of what moviemakers like to call establishing shots. There are a couple of chapters on emotional establishing shots narrating fear and death. And there is a chapter that tries to approach the simple and complicated question of what artists might be doing when making experimentalist movies. Why all this need to trouble the form?
Open Access
AMP- Activated Protein Kinase (AMPK) Activation for the Treatment of Mitochondrial Disease
(2014-07-09) Green, Alexander Edward; Hood, David A.
There are multiple copies of mtDNA per cell and each mtDNA molecule contains the information to encode 13 electron transport chain (ETC) proteins. When mtDNA is depleted, there is a decrease in ETC activity. 5' AMP-activated protein kinase (AMPK) is a kinase that can initiate mitochondrial biogenesis and mitophagy. We hypothesized that treating cells harbouring low numbers of mtDNA with an AMPK activator (5-Aminoimidazole-4-carboxamide ribonucleoside; AICAR) would ameliorate the decrease in ETC activity and improve mtDNA copy number. We developed myoblasts (C2C12 cells) depleted of mtDNA with long-term ethidium bromide treatment. We treated selected clones for 24 hours with 1 mM AICAR to activate AMPK. AICAR treatment decreased markers of mitochondrial biogenesis, mitochondrial function (e.g. maximal cellular respiration), and mitochondrial degradation. Thus, failing to increase the energy producing capacity of the cell, activation of AMPK may have induced an energy sparing mechanism.
Open Access
Presentness: Developing Presence Through Psychophysical Actor-Training
(2014-07-09) Ravid, Ofer; Levin, Laura
Abstract There is a variety of understandings of the notion of presence in theatre and performance studies as well as in the field of actor-training. Presentness, an aspect of presence, is the experience of the emerging here and now as shaped by the performer’s psychophysical engagement with his or her surrounding. It is, thus, a tangible aspect of presence that can be enhanced and developed through training. Presentness developed through training is an acting skill although it does not necessarily determine how actors act in terms of style or form. Rather, techniques of presentness are meant to develop and fine-tune the actor’s instrument as a psychophysical whole that can be used for any style and type of acting. This dissertation examines processes of developing presentness in the practice of three prevalent psychophysical acting techniques in North American actor-training: Viewpoints, Suzuki, and Lecoq. It is based on three years of practice-based research as participant and observer in various training sites with these techniques. Building on detailed descriptions of practiced moments accompanied by interviews and conversations with practitioners and teachers, various emerging manifestations of presentness are exposed to make a complex and deep understanding of this term. Using Maurice Merleau-Ponty’s phenomenology alongside theories from the emerging field of cognitive neuroscience grounds the experiential accounts of ephemeral processes within concrete existing constructs of motility, perception, and cognition.
Open Access
Institutional Strategies and Factors that Contribute to the Engagement of Recent Immigrant Adult Students in Ontario Post-Secondary Education
(2014-07-09) Grabke, Sheldon Vaughn Richard; Axelrod, Paul D.; Theory of participation
The purpose of this study is to provide a unique investigation that yields vital data on barriers experienced by recent immigrant adult students (RIAS), the policies, practices and supports in PSE and their impact on RIAS engagement, and factors that contribute to the engagement of RIAS in Ontario PSE. This examination contributes to and furthers the student engagement in PSE literature by providing an original view into RIAS engagement in PSE. This dissertation involves qualitative and quantitative research methods including 18 key informant interviews, six focus groups, one interview and 434 survey responses as well as historical data, policies, procedures and artifacts at colleges and universities in Ontario. These different methodological attributes bring triangulation of sources and methods into the study. All of the data is analyzed using the student engagement conceptual framework. This study finds that PSE in Ontario seems to know little of the number, type, experiences and engagement of RIAS on campus. This research argues how and why the traditional model of engagement does not apply well to RIAS. Key findings include that RIAS are performing well academically in PSE despite the numerous barriers that they face and their lack of engagement. RIAS strong motivation to complete PSE and their inherent optimism is such that many persist to completion. One fundamental factor contributing to the lack of engagement for RIAS is their minimal social involvement in PSE. Using the findings, this dissertation provides numerous recommendations for changes to institutional policies and procedures to further RIAS engagement. Both academic and social engagement of RIAS in PSE significantly predict the hallmarks of a liberal education. This is a noteworthy reason for PSE to make an investment in the engagement of RIAS in Ontario PSE. This study therefore has implications for theory and practice in PSE in Ontario. Through developing creative ways to remove barriers and augment supports for RIAS in PSE, RIAS may begin to be more engaged in PSE. This noble endeavour can help RIAS more fully develop into engaged citizens and truly assist them in their settlement experience in Ontario.
Open Access
Psychonalysis, Fantasy, Postcoloniality: Derivative Nationalism and Historiography in Post-Ottoman Turkey
(2014-07-09) Ercel, Erkan; Canefe, Nergis
Probably nowhere are the themes of tolerance and multiculturalism more prominently at display than in the recently flourishing literature on Ottoman religious-ethnic communities in Turkey, wherein Ottoman rule, particularly the Millet System of the 15th -17th centuries, is romanticized by Turkish nativist historiographers as a perfect model of peaceful coexistence distinguished by exemplary hospitality and multicultural tolerance toward the Other, the “minorities”, be they Jews, Armenians or Greeks. In this dissertation, I investigate the role of these nativist historians and their historiography in the recuperation of Turkish national imagery, as well as the pitfalls of this sort of remembrance. While doing so, I draw upon the psychoanalytically-inspired concept of fantasy and postcolonial theory to demonstrate how the fantasy of Ottoman tolerance as a melancholic attachment to the past deals with the empire’s loss by pointing to internal and external enemies as threats to the unity and coherence of the nation. Domestically speaking, this fantasy promises to bring back the golden age in as much as enemies new and old will be eliminated on the way to restoring the nation’s power. At the same time, this fantasy takes on an international significance as it captures the essence of the reaction to the European imperative: “you should become multicultural and liberal like us.” The fantasy of the Ottoman Tolerance beats its European Other at its own game by claiming: “we were already multicultural.” Seen in these terms, the analysis of the nostalgic literature on Ottoman peace can illuminate how the “Occident/Western” and “Oriental/Derivative” (i.e. the Ottoman and Turkish) formations of the national imaginary are constructed, remembered and contested in the contemporary Global South. In light of these discussions I will question the conditions and possibilities of the ethics of remembering the Empire, and of entertaining a different relationship to the past in contemporary politics in Europe and Turkey. The key concern of my work is then to inquire into alternative ways to remember the Empire without remaining trapped in the fantasy of Ottoman tolerance, or its obverse, the fantasy of Oriental/Ottoman Despotism.
Open Access
Synthesis of Electron Deficient N-heterocyclic-carbenes and Activity of Imidazol-2-imine Thioureate Ligand on Group 10 Transition Metals
(2014-07-09) Harkness, Michael Byron; Lavoie, Gino G
Previous work in the Lavoie group has resulted in the synthesis of new imidazol-2-imine ligands that have low activity towards ethylene polymerization due to their electron rich nature. In an attempt to alleviate this an electron poor naphthalene-1,4-dione-IMes imidazol-2-imine ligand (L) was synthesized in 90% yield (14a) and coordinated to titanium (LTiCpCl2, 15). The resulting complex successfully polymerizes ethylene at a rate of 75 kg PE mol catalyst–1 h–1. A separate study focused on the coordination of functionalized imidazol-2-imine thioureate ligands (L’) to late transition metal. Three complexes were synthesized. Ni(methylallyl)L’ (7), Pd(allyl)L’ (8), and NiL’2 (9) were isolated in 85, 85, and 61% yields, respectively and all spectroscopically characterized. The X-ray crystallographic structure of 9 shows the unexpected N^S binding mode for the ligand. Complexes 7 and 8 have sparing activity towards ethylene polymerization, neither having productivity above 2 kg PE mol–1 h–1.
Open Access
Operation Untitled
(2014-07-09) Demers, Joshua Andrew; Buchbinder, Amnon
Operation Untitled is a screenplay exploring the self-empowerment of the individual against the socio-political and religious forces that inform the hierarchy of a Catholic high school. The protagonist, Peter Charles who becomes known by the moniker “the Prophet,” is a hard-working student from a lower class background who’s infatuated by his school and society’s promise that hard work = success. When he learns that he loses a life-changing scholarship simply because the recipient, “the Golden Boy” Richard Harding, has influence, his faith in this system is shattered. His subsequent journey of rebellion creates a school-wide revolution and with the power it brings him, the Prophet has a fateful decision: to replace Richard as “the Golden Boy” or to break the cycle of this broken system forever.
Open Access
Dynamics and Control of Smart Structures for Space Applications
(2014-07-09) Orszulik, Ryan Russell; Shan, Jinjun
Smart materials are one of the key emerging technologies for a variety of space systems ranging in their applications from instrumentation to structural design. The underlying principle of smart materials is that they are materials that can change their properties based on an input, typically a voltage or current. When these materials are incorporated into structures, they create smart structures. This work is concerned with the dynamics and control of three smart structures: a membrane structure with shape memory alloys for control of the membrane surface flatness, a flexible manipulator with a collocated piezoelectric sensor/actuator pair for active vibration control, and a piezoelectric nanopositioner for control of instrumentation. Shape memory alloys are used to control the surface flatness of a prototype membrane structure. As these actuators exhibit a hysteretic nonlinearity, they need their own controller to operate as required. The membrane structures surface flatness is then controlled by the shape memory alloys, and two techniques are developed: genetic algorithm and proportional-integral controllers. This would represent the removal of one of the main obstacles preventing the use of membrane structures in space for high precision applications, such as a C-band synthetic aperture radar antenna. Next, an adaptive positive position feedback law is developed for control of a structure with a collocated piezoelectric sensor/actuator pair, with unknown natural frequencies. This control law is then combined with the input shaping technique for slew maneuvers of a single-link flexible manipulator. As an alternative to the adaptive positive position feedback law, genetic algorithms are investigated as both system identification techniques and as a tool for optimal controller design in vibration suppression. These controllers are all verified through both simulation and experiments. The third area of investigation is on the nonlinear dynamics and control of piezoelectric actuators for nanopositioning applications. A state feedback integral plus double integral synchronization controller is designed to allow the piezoelectrics to form the basis of an ultra-precise 2-D Fabry-Perot interferometer as the gap spacing of the device could be controlled at the nanometer level. Next, an output feedback linear integral control law is examined explicitly for the piezoelectric actuators with its nonlinear behaviour modeled as an input nonlinearity to a linear system. Conditions for asymptotic stability are established and then the analysis is extended to the derivation of an output feedback integral synchronization controller that guarantees global asymptotic stability under input nonlinearities. Experiments are then performed to validate the analysis. In this work, the dynamics and control of these smart structures are addressed in the context of their three applications. The main objective of this work is to develop effective and reliable control strategies for smart structures that broaden their applicability to space systems.