8 resultados para Stand-Alone and Grid Connected PV applications

em Brock University, Canada


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Changes in the configuration of a tree stern result insignificant differences in its total volume and in the proportion of that volume that is merchantable timber. Tree allometry, as represented by stem-fo~, is the result of the vertical force of gravity and the horizontal force of wind. The effect of wind force is demonstrated in the relationship between stem-form, standclosure and site-conditions. An increase in wind force on the individual tree due to a decrease in stand density should produce a more tapered tree. The density of the stand is determined by the conditions that the trees are growing under. The ability of the tree to respond to increased wind force may also be a function of these conditions . This stem-form/stand-closure/site-conditions relationship was examined using a pre-existing database from westcentral Alberta. This database consisted of environmental, vegetation, soils and timber data covering a wide range of sites. There were 653 sample trees with 82 variables that formed the basis of the analysis. There were eight tree species consisting of Pinus contorta, Picea mariana, Picea engelmannii x glauca, Abies lasiocarpa, Larix laricina, Populus tremuloides, Betula papyrifera and Populus balsamifera plus a comprehensive all-species data set. As the actual conformation of the stern is very individual, stem-fo~was represented by the diameter at breast height to total height r~tio. The four stand-closure variables, crown closure, total basal area, total volume and total number of stems were reduced to total basal area and total number of stems utilizing a bivariate correlation matrix by species. Site-conditions were subdivided into macro, meso and micro variables and reduced in number 3 using cross-tabulations, bivariate correlation and principal components analysis as screening tools. The stem-fo~/stand-closure relationship was examined using bivariate correlation coefficients for stem-fo~ with total number of stems and stem-fo~ with total basal area. The stem-fo~/site-conditions and the stand-closure/site- conditions relationships were examined using multiple correlation coefficients. The stem-form/stand-closure/site-conditions relationship was examined using multiple correlation coefficients in separate analyses for both total number of stems and total basal area. An increase in stand-closure produced a decrease in stem-form for both total number of stems and total basal area for most species. There was a significant relationship between stem-form and site-conditions and between stand-closure and site-conditions for both total number of stems and total basal area for most species. There was a significant relationship between the stemform and site-conditions, including the stand-closure, for most species; total number of stems was involved independently of the site-conditions in the prediction of stem-form and total basal area was not. Larix laricina and Betula papyrifera were the exceptions to the trends observed with most species. The influence of both stand-closure (total number of stems in particular) and site-conditions (elevation in particular) suggest that forest management practices should include these- ecological parameters in determining appropriate restocking levels.

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I will argue that the doctrine of eternal recurrence of the same no better interprets cosmology than pink elephants interpret zoology. I will also argue that the eternal-reiurn-of-the-same doctrine as what Magnus calls "existential imperative" is without possibility of application and thus futile. To facilitate those arguments, the validity of the doctrine of the eternal recurrence of the same will be tested under distinct rubrics. Although each rubric will stand alone, one per chapter, as an evaluation of some specific aspect of eternal recurrence, the rubric sequence has been selected to accommodate the identification of what I shall be calling logic abridgments. The conclusions to be extracted from each rubric are grouped under the heading CONCLUSION and appear immediately following rubric ten. Then, or if, at the end of a rubric a reader is inclined to wonder which rubric or topic is next, and why, the answer can be found at the top of the following page. The question is usually answered in the very first sentence, but always answered in the first paragraph. The first rubric has been placed in order by chronological entitlement in that it deals with the evolution of the idea of eternal recurrence from the time of the ancient Greeks to Nietzsche's August, 1881 inspiration. This much-recommended technique is also known as starting at the beginning. Rubric 1 also deals with 20th. Century philosophers' assessments of the relationship between Nietzsche and ancient Greek thought. The only experience of E-R, Zarathustra's mountain vision, is second only because it sets the scene alluded to in following rubrics. The third rubric explores .ii?.ih T jc,i -I'w Nietzsche's evaluation of rationality so that his thought processes will be understood appropriately. The actual mechanism of E-R is tested in rubric four...The scientific proof Nietzsche assembled in support of E-R is assessed by contemporary philosophers in rubric five. E-R's function as an ethical imperative is debated in rubrics six and seven.. .The extent to which E-R fulfills its purpose in overcoming nihilism is measured against the comfort assured by major world religions in rubric eight. Whether E-R also serves as a redemption for revenge is questioned in rubric nine. Rubric ten assures that E-R refers to return of the identically same and not merely the similar. In addition to assemblage and evaluation of all ten rubrics, at the end of each rubric a brief recapitulation of its principal points concludes the chapter. In this essay I will assess the theoretical conditions under which the doctrine cannot be applicable and will show what contradictions and inconsistencies follow if the doctrine is taken to be operable. Harold Alderman in his book Nietzsche's Gift wrote, the "doctrine of eternal recurrence gives us a problem not in Platonic cosmology, but in Socratic selfreflection." ^ I will illustrate that the recurrence doctrine's cosmogony is unworkable and that if it were workable, it would negate self-reflection on the grounds that selfreflection cannot find its cause in eternal recurrence of the same. Thus, when the cosmology is shown to be impossible, any expected ensuing results or benefits will be rendered also impossible. The so-called "heaviest burden" will be exposed as complex, engrossing "what if speculations deserving no linkings to reality. To identify ^Alderman p. 84 abridgments of logic, contradictions and inconsistencies in Nietzsche's doctrine of eternal recurrence of the same, I. will examine the subject under the following schedule. In Chapter 1 the ancient origins of recurrence theories will be introduced. ..This chapter is intended to establish the boundaries within which the subsequent chapters, except Chapter 10, will be confined. Chapter 2, Zarathustra's vision of E-R, assesses the sections of Thus Spoke Zarathustra in which the phenomenon of recurrence of the same is reported. ..Nihilism as a psychological difficulty is introduced in this rubric, but that subject will be studied in detail in Chapter 8. In Chapter 2 the symbols of eternal recurrence of the same will be considered. Whether the recurrence image should be of a closed ring or as a coil will be of significance in many sections of my essay. I will argue that neither symbolic configuration can accommodate Nietzsche's supposed intention. Chapter 3 defends the description of E-R given by Zarathustra. Chapter 4, the cosmological mechanics of E-R, speculates on the seriousness with which Nietzsche might have intended the doctrine of eternal recurrence to be taken. My essay reports, and then assesses, the argument of those who suppose the doctrine to have been merely exploratory musings by Nietzsche on cosmological hypotheses...The cosmogony of E-R is examined. In Chapter 5, cosmological proofs tested, the proofs for Nietzsche's doctrine of return of the same are evaluated. This chapter features the position taken by Martin ' Heidegger. My essay suggests that while Heidegger's argument that recurrence of the same is a genuine cosmic agenda is admirable, it is not at all persuasive. Chapter 6, E-R is an ethical imperative, is in essence the reporting of a debate between two scholars regarding the possibility of an imperative in the doctrine of recurrence. Their debate polarizes the arguments I intend to develop. Chapter 7, does E-R of the same preclude alteration of attitudes, is a continuation of the debate presented in Chapter 6 with the focus shifted to the psychological from the cosmological aspects of eternal recurrence of the same. Chapter 8, Can E-R Overcome Nihilism?, is divided into two parts. In the first, nihilism as it applies to Nietzsche's theory is discussed. ..In part 2, the broader consequences, sources and definitions of nihilism are outlined. My essay argues that Nietzsche's doctrine is more nihilistic than are the world's major religions. Chapter 9, Is E-R a redemption for revenge?, examines the suggestion extracted from Thus Spoke Zarathustra that the doctrine of eternal recurrence is intended, among other purposes, as a redemption for mankind from the destructiveness of revenge. Chapter 10, E-R of the similar refuted, analyses a position that an element of chance can influence the doctrine of recurrence. This view appears to allow, not for recurrence of the same, but recurrence of the similar. A summary will recount briefly the various significant logic abridgments, contradictions, and inconsistencies associated with Nietzsche's doctrine of eternal recurrence of the same. In the 'conclusion' section of my essay my own opinions and observations will be assembled from the body of the essay.

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This case study traces the evolution of library assignments for biological science students from paper-based workbooks in a blended (hands-on) workshop to blended learning workshops using online assignments to online active learning modules which are stand-alone without any face-to-face instruction. As the assignments evolved to adapt to online learning supporting materials in the form of PDFs (portable document format), screen captures and screencasting were embedded into the questions as teaching moments to replace face-to-face instruction. Many aspects of the evolution of the assignment were based on student feedback from evaluations, input from senior lab demonstrators and teaching assistants, and statistical analysis of the students’ performance on the assignment. Advantages and disadvantages of paper-based and online assignments are discussed. An important factor for successful online learning may be the ability to get assistance.

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Background: Lung cancer (LC) is the leading cause of cancer death in the developed world. Most cancers are associated with tobacco smoking. A primary hope for reducing lung cancer has been prevention of smoking and successful smoking cessation programs. To date, these programs have not been as successful as anticipated. Objective: The aim of the current study was to evaluate whether lung cancer screening combining low dose computed tomography with autofluorescence bronchoscopy (combined CT & AFB) is superior to CT or AFB screening alone in improving lung cancer specific survival. In addition, the extent of improvement and ideal conditions for combined CT & AFB screening were evaluated. Methods: We applied decision analysis and Monte Carlo simulation modeling using TreeAge Software to evaluate our study aims. Histology- and stage specific probabilities of lung cancer 5-year survival proportions were taken from Surveillance and Epidemiologic End Results (SEER) Registry data. Screeningassociated data was taken from the US NCI Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO), National Lung Screening Trial (NLST), and US NCI Lung Screening Study (LSS), other relevant published data and expert opinion. Results: Decision Analysis - Combined CT and AFB was the best approach at Improving 5-year survival (Overall Expected Survival (OES) in the entire screened population was 0.9863) and in lung cancer patients only (Lung Cancer Specific Expected Survival (LOSES) was 0.3256). Combined screening was slightly better than CT screening alone (OES = 0.9859; LCSES = 0.2966), and substantially better than AFB screening alone (OES = 0.9842; LCSES = 0.2124), which was considerably better than no screening (OES = 0.9829; LCSES = 0.1445). Monte Carlo simulation modeling revealed that expected survival in the screened population and lung cancer patients is highest when screened using CT and combined CT and AFB. CT alone and combined screening was substantially better than AFB screening alone or no screening. For LCSES, combined CT and AFB screening is significantly better than CT alone (0.3126 vs. 0.2938, p< 0.0001). Conclusions: Overall, these analyses suggest that combined CT and AFB is slightly better than CT alone at improving lung cancer survival, and both approaches are substantially better than AFB screening alone or no screening.

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Multiple measures have been devised by clinicians and theorists from many different backgrounds for the purpose of assessing the influence of the frontal lobes on behaviour. Some utilize self-report measures to investigate behavioural characteristics such as risktaking, sensation seeking, impulsivity, and sensitivity to reward and punishment in an attempt to understand complex human decision making. Others rely more on neuroimaging and electrophysiological investigation involving experimental tasks thought to demonstrate executive functions in action, while other researchers prefer to study clinical populations with selective damage. Neuropsychological models of frontal lobe functioning have led to a greater appreciation of the dissociations among various aspects of prefrontal cortex function. This thesis involves (1) an examination of various psychometric and experimental indices of executive functions for coherence as one would predict on the basis of highly developed neurophysiological models of prefrontal function, particularly those aspects of executive function that involve predominantly cognitive abilities versus processes characterized by affect regulation; and (2) investigation of the relations between risk-taking, attentional abilties and their associated characteristics using a neurophysiological model of prefrontal functions addressed in (1). Late adolescence is a stage in which the prefrontal cortices undergo intensive structural and functional maturational changes; this period also involves increases in levels of risky and sensation driven behaviours, as well as a hypersensitivity to reward and a reduction in inhibition. Consequently, late adolescence spears to represent an ideal developmental period in which to examine these decision-making behaviours due to the maximum variability of behavioural characteristics of interest. Participants were 45 male undergraduate 18- to 19-year olds, who completed a battery of measures that included self-report, experimental and behavioural measures designed to assess particular aspects of prefrontal and executive functioning. As predicted, factor analysis supported the grouping of executive process by type (either primarily cognitive or affective), conforming to the orbitofrontal versus dorsolateral typology; risk-taking and associated characteristics were associated more with the orbitofrontal than the dorsolateral factor, whereas attentional and planning abilities tended to correlate more strongly with the dorsolateral factor. Results are discussed in light of future assessment, investigation and understanding of complex human decision-making and executive functions. Implications, applications and suggestions for future research are also proposed.

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This thesis explored the development of several methodologies for the stereoselective construction of ligand frameworks and some of their applications. The first segment concerns the application of an enantioselective lithiation at an Sp3_ hybridized position adjacent to nitrogen by means of the widely used and typically highly effective enantioselective lithiation with ( -)-sparteine. This investigation was intended to develop a method to install chirality into a system that would be converted into a family of diaminoylidenes for use as phosphine mimics in transition metal catalysis or as nucleophilic reagents. Molecular modeling of the system revealed some key interactions between the substrate and (-)-sparteine that provided general insight into the diamine's mode of action and should lend some predictive value to its future applications. The second portion focuses on the development of methods to access 1,2- disubstituted aminoferrocenes, an underexplored class of metallocenes possessing planar chirality. Two routes were examined involving a diastereoselective and an enantioselective pathway, where the latter method made use of the first BF3-mediated lithiation-substitution to install planar chirality. Key derivatives such as 1,2- aminophosphines, made readily accessible by the new route, were evaluated as ligands for Pd(II), Pt(II) and Ir(I). These complexes show activity in a number of transformations with both achiral and prochiral substrates. Optimization experiments were conducted to prepare enantiomerically enriched 2-substituted-I-aminoferrocenes by direct asymmetric lithiation of BF3-coordinated tertiary aminoferrocenes. A predictive computational model describing the transition state of this reaction was developed in collaboration with Professor Travis Dudding's group (Department of Chemistry, Brock University). The predicted stereochemistry of the process was confirmed by single-crystal X-ray analysis of a 2-phosphino-l-dimethylaminoferrocene derivative. Enantiomerically pure samples of the aminophosphine ligands derived from this new process have given promising preliminary results in the enantioselective hydrogenation of prochiral alkenes and warrant further stUdy in metal-mediated catalysis.

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This thesis investigated the subcellular location of skeletal muscle PLIN proteins (PLIN2, PLIN3, and PLIN5) as well as protein interactions with ATGL and HSL at rest and following lipolytic stimulation. In addition, the serine phosphorylation state of PLIN2, PLIN3, and PLIN5 was determined at rest and following lipolytic stimulation. An isolated whole muscle technique was used to study the effects of contraction and epinephrine-induced lipolysis. This method allowed for the examination of the effects of contraction and epinephrine alone and in combination. Further, the soleus was chosen for investigating the role of PLIN proteins in skeletal muscle lipolysis due to its suitability for isolated incubation, and the fact that it is primarily oxidative in nature (~80% type I fibres). It has also been previously shown to have the greatest reliance on lipid metabolism and for this reason is ideal for investigating the role of PLIN proteins in lipolysis. Immunofluorescence microscopy revealed that skeletal muscle lipid droplets are partially co-localized to both PLIN2 and PLIN5 and that contraction does not affect the amount of colocalization, indicating that PLIN5 is not recruited to lipid droplets with contraction (PLIN2 ~65%; PLIN5 ~56%). Results from the immunoprecipitation studies revealed that with lipolysis in skeletal muscle the interaction between ATGL and CGI-58 is increased (study 2: 128% with contraction, p<0.05; study 3: 50% with contraction, 25% epinephrine, 80% contraction + epinephrine, p>0.05). Further PLIN2, PLIN3, and PLIN5 all interact with ATGL and HSL, while only PLIN3 and PLIN5 interact with CGI-58. Among these interactions, the association between PLIN2 and ATGL decreases with lipolytic stimulation (study 2: 21% with contraction, p<0.05). Finally our results demonstrate that PLIN3 and PLIN5 are serine phosphorylated at rest and that the level of phosphorylation remains unchanged in the face of either contractile or adrenergic stimulation. In summary, the regulation of skeletal muscle lipolysis is a complex process involving multiple proteins and enzymes. The skeletal muscle PLIN proteins likely play a role in skeletal muscle lipid droplet dynamics, and the data from this thesis indicate that these proteins may work together in regulating lipolysis by interaction with both ATGL and HSL.

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The question of how we can encourage creative capacities in young people has never been more relevant than it is today (Pink, 2006; Robinson as cited in TEDtalksDirector, 2007; Eisner as cited in VanderbiltUniversity, 2009). While the world is rapidly evolving, education has the great challenge of adapting to keep up. Scholars say that to meet the needs of 21st century learners, pedagogy must focus on fostering creative skills to enable students to manage in a future we cannot yet envision (Robinson as cited in TEDtalksDirector, 2007). Further, research demonstrates that creativity thrives with autonomy, support, and without judgment (Amabile, 1996; Codack [Zak], 2010; Harrington, Block, & Block, 1987; Holt, 1989; Kohn, 1993). So how well are schools doing in this regard? How do alternative models of education nurture or neglect creativity, and how can this inform teaching practice all around? In other words, ultimately, how can we nurture creativity in education? This documentary explores these questions from a scholarly art-based perspective. Artist/researcher/teacher Rebecca Zak builds on her experience in the art studio, academia, and the art classroom to investigate the various philosophies and strategies that diverse educational models implement to illuminate the possibilities for educational and paradigmatic transformation. The Raising Creativity documentary project consists of multiple parts across multiple platforms. There are five videos in the series that answer the why, who, how, what, and now what about creativity in education respectively (i.e., why is this topic important, who has spoken/written on this topic already, how will this issue be investigated this time, what was observed during the inquiry, and now what will this mean going forward?). There is also a self-reflexive blog that addresses certain aspects of the topic in greater depth (located here, on this website) and in the context of Rebecca's lived experience to complement the video format. Together, all video and blog artifacts housed on this website function as a polyptych, wherein the pieces can stand alone individually yet are intended to work together and fulfill the dissertation requirements for Rebecca's doctorate degree in education in reimagined ways.