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Information Literacy in the Knowledge Society: Empowering Learners for a Better TomorrowChakrvarty, Rupak January 2008 (has links)
We are finding ourselves in a rapidly growing and complex digital environment which has in turn increased our dependency on information. But there is increasing evidence that our information skills are not keeping pace in any systematic fashion. We all need help to sharpen the techniques and skills to manage information. Present paper is an attempt to present the current status of information literacy and the emerging roles of libraries and schools of LIS education in augmenting the information literacy campaign.
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The Distribution and Function of Number in AzeriZareikar, Gita 29 August 2018 (has links)
In this dissertation, I study the distribution of number in Azeri within the Exo-
Skeletal model of Borer (2005a). I adopt the Exo-Skeletal model's assumption that
number marking is a syntactic rather than a lexical process.
Following Borer (2005a), I assume that, in order to be counted, nouns need to
be individuated by means of a functional category Div. In Borer's model, plural
markers and classifiers are argued to be generated in DivP. However, unlike Borer,
I propose that the plural marker in Azeri is not an individuator. Instead, it solely
marks plurality. Under my proposal, individuation in Azeri is morphologically null.
Moreover, I argue that classifiers do not belong to the category of individuators
either and their function is to unitize the individuated object. Therefore, I consider
classifiers in Azeri to be generated on a cluster head where they contribute to a
group formation process. The generation of the plural marker and the classifier on
heads other than division derives the conclusion that the individuation in Azeri is
morphologically null.
Furthermore, I investigate the interpretation of number in the verbal domain,
i.e. in TP, in the presence of the viewpoint aspect in both telic and atelic contexts.
I argue that the singular interpretation of the Azeri bare noun is linked to the
projection of AspQ, where the specific interpretation of the bare noun arises under
the effect of the perfective aspect. The presence of AspQ yields a telic interpretation
of the event structure, and the DP in the specifier of AspQ is the subject of
quantity (Borer, 2005a). Moreover, according to Borer, number ambiguous nouns
are generated in atelic structures where AspQ is absent. In this case, the DP does
not have to be the subject of quantity and the availability of quantity on the DP
remains optional. Nevertheless, (non-)specific interpretation of the noun in telic
and atelic contexts in Azeri, I argue to be due to the impact of the viewpoint
aspect.
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Evaluating and Improving Current Metapopulation Theory for Community and Species-level ModelsBrown, Natasha A. 02 October 2018 (has links)
No description available.
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A PRECISE A. C. NULL METHOD OF DETERMINING MAGNETIC FIELDS IN A BETA-RAY SPECTROMETERKoenig, Raymond 10 1900 (has links)
This thesis is written in three sections; the first presents a critical survey of methods which have been used to measure magnetic fields; the second describes the construction of an A.C. null method capable of comparing two fields to one part in 30,000, and the third discusses its performance. / Thesis / Master of Science (MS)
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Adapting to Seniors: Computer Training for Older AdultsBean, Carol, Laven, Michael 10 1900 (has links)
Teaching older adults to use computers requires taking into account the effects of the aging process. Techniques which work for a younger generation will not necessarily be successful with older novices, but modifications which improve the outcome for older students also work well with younger learners. This article explains how computer trainers at the Palm Beach County Library System's North County Regional Library created a mousing class and modified existing classes to create a series of four classes designed specifically for older adults who have never used a computer before. The article also summarizes the difficulties older adults face in learning to use computers, and ways to improve the learning outcome.
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Maximal controllability via reduced parameterisation model predictive controlMedioli, Adrian January 2008 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / This dissertation presents some new approaches to addressing the main issues encountered by practitioners in the implementation of linear model predictive control(MPC), namely, stability, feasibility, complexity and the size of the region of attraction. When stability guaranteeing techniques are applied nominal feasibility is also guaranteed. The most common technique for guaranteeing stability is to apply a special weighting to the terminal state of the MPC formulation and to constrain the state to a terminal region where certain properties hold. However, the combination of terminal state constraints and the complexity of the MPC algorithm result in regions of attraction that are relatively small. Small regions of attraction are a major problem for practitioners. The main approaches used to address this issue are either via the reduction of complexity or the enlargement of the terminal region. Although the ultimate goal is to enlarge the region of attraction, none of these techniques explicitly consider the upper bound of this region. Ideally the goal is to achieve the largest possible region of attraction which for constrained systems is the null controllable set. For the case of systems with a single unstable pole or a single non-minimum phase zero their null controllable sets are defined by simple bounds which can be thought of as implicit constraints. We show in this thesis that adding implicit constraints to MPC can produce maximally controllable systems, that is, systems whose region of attraction is the null controllable set. For higher dimensional open-loop unstable systems with more than one real unstable mode, the null controllable sets belong to a class of polytopes called zonotopes. In this thesis, the properties of these highly structured polytopes are used to implement a new variant of MPC, which we term reduced parameterisation MPC (RP MPC). The proposed new strategy dynamically determines a set of contractive positively invariant sets that require only a small number of parameters for the optimisation problem posed by MPC. The worst case complexity of the RP MPC strategy is polylogarithmic with respect to the prediction horizon. This outperforms the most efficient on-line implementations of MPC which have a worst case complexity that is linear in the horizon. Hence, the reduced complexity allows the resulting closed-loop system to have a region of attraction approaching the null controllable set and thus the goal of maximal controllability.
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Early null and overt subjects in the Spanish of simultaneous English-Spanish bilinguals and Crosslinguistic InfluenceVilla-García, Julio, Suárez-Palma, Imanol January 2016 (has links)
This study assesses the scope of the Crosslinguistic Influence (CLI) hypothesis’ predictions with regard to early bilingual acquisition. To this end, we analyze longitudinal corpus data from four bilinguals attesting the acquisition of subjecthood (null versus overt; preverbal versus postverbal) and the pragmatic adequacy of early null and overt subjects in a null-subject language (i.e., Spanish) in combination with a language differing in its pro-drop parameter setting (i.e., English). Our results indicate that CLI barely affects the development of subjects in the null-subject language at the initial stages, namely at the outset of null and overt subjects, and in turn support the Separate Development Hypothesis. Our bilingual cohort patterns with their Spanish-acquiring monolingual peer in that both groups display comparable proportions of null subjects as well as acquisitional trajectories of null and overt subjects at the early stages of acquisition. Much like monolinguals, bilinguals begin to produce preverbal and postverbal subjects concurrently. The bilingual children and the monolingual child of this study actually produce extremely high rates of pragmatically appropriate covert and overt subjects, which are for the most part target-like from the start, thus pointing to the absence of CLI effects. In light of monolingual and bilingual data, the paper also revisits the hotly debated issue of the ‘no overt subject’ stage of Grinstead (1998, et seq.), its existence in child Spanish being questionable.
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On the Neutralome of Great Apes and Nearest Neighbor Search in Metric SpacesWoerner, August Eric, Woerner, August Eric January 2016 (has links)
Problems of population genetics are magnified by problems of big data. My dissertation spans the disciplines of computer science and population genetics, leveraging computational approaches to biological problems to address issues in genomics research. In this dissertation I develop more efficient metric search algorithms. I also show that vast majority of the genomes of great apes are impacted by the forces of natural selection. Finally, I introduce a heuristic to identify neutralomes—regions that are evolving with minimal selective pressures—and use these neutralomes for inferences on effective population size in great apes. We begin with a formal and far-reaching problem that impacts a broad array of disciplines including biology and computer science; the 𝑘-nearest neighbors problem in generalized metric spaces. The 𝑘-nearest neighbors (𝑘-NN) problem is deceptively simple. The problem is as follows: given a query q and dataset D of size 𝑛, find the 𝑘-closest points to q. This problem can be easily solved by algorithms that compute 𝑘th order statistics in O(𝑛) time and space. It follows that if D can be ordered, then it is perhaps possible to solve 𝑘-NN queries in sublinear time. While this is not possible for an arbitrary distance function on the points in D, I show that if the points are constrained by the triangle inequality (such as with metric spaces), then the dataset can be properly organized into a dispersion tree (Appendix A). Dispersion trees are a hierarchical data structure that is built around a large dispersed set of points. Dispersion trees have construction times that are sub-quadratic (O(𝑛¹·⁵ log 𝑛)) and use O(𝑛) space, and they use a provably optimal search strategy that minimizes the number of times the distance function is invoked. While all metric data structures have worst-case O(𝑛) search times, dispersion trees have average-case search times that are substantially faster than a large sampling of comparable data structures in the vast majority of spaces sampled. Exceptions to this include extremely high dimensional space (d>20) which devolve into near-linear scans of the dataset, and unstructured low-dimensional (d<6) Euclidean spaces. Dispersion trees have empirical search times that appear to scale as O(𝑛ᶜ) for 0<c<1. As solutions to the 𝑘-NN problem are in general too slow to be used effectively in the arena of big data in genomics, it is my hope that dispersion trees may help lift this barrier. With source-code that is freely available for academic use, dispersion trees may be useful for nearest neighbor classification problems in machine learning, fast read-mapping against a reference genome, and as a general computational tool for problems such clustering. Next, I turn to problems in population genomics. Genomic patterns of diversity are a complex function of the interplay between demographics, natural selection and mechanistic forces. A central tenet of population genetics is the neutral theory of molecular evolution which states the vast majority of changes at the molecular level are (relatively) selectively neutral; that is, they do not effect fitness. A corollary of the neutral theory is that the frequency of most alleles in populations are dictated by neutral processes and not selective processes. The forces of natural selection impact not just the site of selection, but linked neutral sites as well. I proposed an empirical assessment of the extents of linked selection in the human genome (Appendix B). Recombination decouples sites of selection from the genomic background, thus it serves to mitigate the effects of linked selection. I use two metrics on recombination, both the minimum genetic distance to genes and local rates of recombination, to parse the effects of linked selection into selection from genic and nongenic sources in the human genome. My empirical assessment shows profound linked selective effects from nongenic sources, with these effects being greater than that of genic sources on the autosomes, as well as generally greater effects on the X chromosome than on the autosomes. I quantify these trends using multiple linear regression, and then I model the effects of linked selection to conserved elements across the whole of the genome. Places predicted to be neutral by my model do not, unlike the vast majority of the genome, show these linked selective effects. This demonstrates that linkage to these regulatory elements, and not some other mechanistic force, accounts for our findings. Further, neutrally evolving regions are extremely rare (~1%) in the genome, and despite generally larger linked selective effects on the X chromosome, the size of this “neutralome” is proportionally larger on the X chromosome than on the autosomes. To account for this and to extend my findings to other great apes I improve on my procedure to find neutralomes, and apply this procedure to the genome of humans, Nigerian chimpanzees, bonobos, and western lowland gorillas (Appendix C). In doing so I show that like humans, these other apes are also enormously impacted by linked selection, with their neutralomes being substantially smaller than the neutralomes of humans. I then use my genomic predictions on neutrality to see how the landscape of linked selection changes across the X chromosome and the autosomes in regions close to, and far from, genes. While I had previously demonstrated the linked selective forces near genes are stronger on the X chromosome than on the autosomes in these taxa, I show that regions far from genes show the opposite; regions far from genes show more selection from noncoding targets on the autosomes than on the X chromosome. This finding is replicated across our great ape samples. Further, inferences on the relative effective population size of the X chromosome and the autosomes both near and far from genes can be biased as a result.
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PROBLEMS IN NULL CORRECTOR DESIGNLytle, John D. 25 April 1969 (has links)
QC 351 A7 no. 39 / Optical systems known as "null correctors" are often required to test
certain aspheric optical surfaces. This report classifies these systems on
the basis of their first -order geometry and analyzes the merits of each type.
The behavior of optical aberrations, especially spherical aberration, in
these systems is examined in the context of computer optimization techniques,
particular attention being given to some design problems unique to null correcting systems.
Orthonormal concepts are applied to the problem of reducing spherical
aberration in null correctors. It is shown that exceedingly simple merit
functions may be constructed to streamline the optimization process. These
merit functions are composed of simple linear sums of the angular spherical
aberration coefficients B1, B3, B5, and B7. Thus, minimizing the following
sums will improve nearly diffraction - limited systems:
( -
13 B1 +
1
B3 - g' B5 - B7) , ( 4.131 - B3 - B5) , ( - 2B1 - B3) ,
and ( - B1) /1-5- 3/7 3 or ( 120 B3 + 960 B5 + 840 B7 ) , ( 840 B5 + 2520 B7) , and ( 840 B7)
Non -diffraction - limited systems may be optimized by minimizing the sums
( 6 B3 + 5 B5 + 5 B7) , ( p B5 + 3 B7) , and ( 1 0 B7)
To demonstrate the effectiveness of the techniques discussed, the process of designing a specific null correcting system is followed in detail.
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Species Assemblage Structure and Ecomorphological Convergence in Perciform Fishes (Cichlidae and Centrarchidae) in Tropical and Temperate Floodplain RiversMontana, Carmen 1976- 14 March 2013 (has links)
In this study, I used two independent perciform lineages (Neotropical Cichlidae and Nearctic Centrarchidae) to examine patterns of species richness and species coexistence a two spatial scales (e.g., macrohabitat and mesohabitat) and to examine inter-faunal patterns of ecomorphological convergence. The study was conducted during the low-water periods in four lowland rivers: the Cinaruco in Venezuela, the Tambopata in Peru, and the Neches and the Brazos rivers in Texas (USA). These rivers were chosen because of their similar characteristics, in terms of geomorphology, sediments, and water quality. The Cinaruco River and the Neches River have clear slightly-stained waters, whereas the Tambopata and the Brazos River have turbid waters with high loads of suspended sediments. I used morphological approaches as a surrogate to investigate patterns of species distribution in niche space, and predict patterns of species richness at different spatial scales. Despite high variation in the number of species in these two perciform assemblages, morphological analysis based on the means and standard deviations of nearest neighbor distance (NND) and mean distance to centroid (CD) revealed similar trends of morphological similarity in relation to species richness. Comparison of observed versus randomized data mesohabitat scale for all four rivers generally supported the niche expansion model of response to increase in species richness. At the scale of mesohabitats within rivers, most species assemblages appear to be organized by competitive interactions in accordance with the niche expansion model. The tropical species-rich Cinaruco River revealed particularly strong support for the niche expansion model. Intercontinental comparison of functional morphology and diets based on analysis of stomach contents and stable isotope ratios indicated broad morphological and dietary overlap between cichlid and centrarchid assemblages. For the most part, morphological ordinations showed that the two groups have diversified in a parallel manner within the confines of ram-suction modes of prey ingestion. This study concludes that even though differences are observed in historical and stochastic factors structuring fish assemblages in different geographic regions, consistent patterns of convergence at the species and assemblage levels results from natural selection under similar environmental conditions.
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