928 resultados para Decimal numbers and fractional numbers
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This data set contains information on vegetation cover, i.e. the proportion of soil surface area that is covered by different categories of plants per estimated plot area. Data was collected on the plant community level (sown plant community, weed plant community, dead plant material, and bare ground) and on the level of individual plant species in case of the sown species. Data presented here is from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2007, vegetation cover was estimated twice in June and August just prior to mowing (during peak standing biomass) on all experimental plots of the Main Experiment. Cover was visually estimated in a central area of each plot 3 by 3 m in size (approximately 9 m²) using a decimal scale (Londo). Cover estimates for the individual species (and for target species + weeds + bare ground) can add up to more than 100% because the estimated categories represented a structure with potentially overlapping multiple layers. In 2007, dead plant material was found only in a few plots. Therefore, cover of dead plant material is zero for most of the 82 plots.
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This data set contains information on vegetation cover, i.e. the proportion of soil surface area that is covered by different categories of plants per estimated plot area. Data was collected on the plant community level (sown plant community, weed plant community, dead plant material, and bare ground) and on the level of individual plant species in case of the sown species. Data presented here is from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2004, vegetation cover was estimated twice in May and August just prior to mowing (during peak standing biomass) on all experimental plots of the Main Experiment. Cover was visually estimated in a central area of each plot 3 by 3 m in size (approximately 9 m²) using a decimal scale (Londo). Cover estimates for the individual species (and for target species + weeds + bare ground) can add up to more than 100% because the estimated categories represented a structure with potentially overlapping multiple layers. In 2004, cover on the community level was only estimated for the sown plant community, weed plant community and bare soil. In contrast to later years, cover of dead plant material was not estimated.
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We tested the prediction that, if hoverflies are Batesian mimics, this may extend to behavioral mimicry such that their numerical abundance at each hour of the day (the daily activity pattern) is related to the numbers of their hymenopteran models. After accounting for site, season, microclimatic responses and for general hoverfly abundance at three sites in north-west England, the residual numbers of mimics were significantly correlated positively with their models 9 times out of 17, while 16 out of 17 relationships were positive, itself a highly significant non-random pattern. Several eristaline flies showed significant relationships with honeybees even though some of them mimic wasps or bumblebees, perhaps reflecting an ancestral resemblance to honeybees. There was no evidence that good and poor mimics differed in their daily activity pattern relationships with models. However, the common mimics showed significant activity pattern relationships with their models, but the rarer mimics did not. We conclude that many hoverflies show behavioral mimicry of their hymenopteran models.
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This dissertation has two almost unrelated themes: privileged words and Sturmian words. Privileged words are a new class of words introduced recently. A word is privileged if it is a complete first return to a shorter privileged word, the shortest privileged words being letters and the empty word. Here we give and prove almost all results on privileged words known to date. On the other hand, the study of Sturmian words is a well-established topic in combinatorics on words. In this dissertation, we focus on questions concerning repetitions in Sturmian words, reproving old results and giving new ones, and on establishing completely new research directions. The study of privileged words presented in this dissertation aims to derive their basic properties and to answer basic questions regarding them. We explore a connection between privileged words and palindromes and seek out answers to questions on context-freeness, computability, and enumeration. It turns out that the language of privileged words is not context-free, but privileged words are recognizable by a linear-time algorithm. A lower bound on the number of binary privileged words of given length is proven. The main interest, however, lies in the privileged complexity functions of the Thue-Morse word and Sturmian words. We derive recurrences for computing the privileged complexity function of the Thue-Morse word, and we prove that Sturmian words are characterized by their privileged complexity function. As a slightly separate topic, we give an overview of a certain method of automated theorem-proving and show how it can be applied to study privileged factors of automatic words. The second part of this dissertation is devoted to Sturmian words. We extensively exploit the interpretation of Sturmian words as irrational rotation words. The essential tools are continued fractions and elementary, but powerful, results of Diophantine approximation theory. With these tools at our disposal, we reprove old results on powers occurring in Sturmian words with emphasis on the fractional index of a Sturmian word. Further, we consider abelian powers and abelian repetitions and characterize the maximum exponents of abelian powers with given period occurring in a Sturmian word in terms of the continued fraction expansion of its slope. We define the notion of abelian critical exponent for Sturmian words and explore its connection to the Lagrange spectrum of irrational numbers. The results obtained are often specialized for the Fibonacci word; for instance, we show that the minimum abelian period of a factor of the Fibonacci word is a Fibonacci number. In addition, we propose a completely new research topic: the square root map. We prove that the square root map preserves the language of any Sturmian word. Moreover, we construct a family of non-Sturmian optimal squareful words whose language the square root map also preserves.This construction yields examples of aperiodic infinite words whose square roots are periodic.
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Mode of access: Internet.
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We discover novel topological effects in the one-dimensional Kitaev chain modified by long-range Hamiltonian deformations in the hopping and pairing terms. This class of models display symmetry-protected topological order measured by the Berry/Zak phase of the lower-band eigenvector and the winding number of the Hamiltonians. For exponentially decaying hopping amplitudes, the topological sector can be significantly augmented as the penetration length increases, something experimentally achievable. For power-law decaying superconducting pairings, the massless Majorana modes at the edges get paired together into a massive nonlocal Dirac fermion localized at both edges of the chain: a new topological quasiparticle that we call topological massive Dirac fermion. This topological phase has fractional topological numbers as a consequence of the long-range couplings. Possible applications to current experimental setups and topological quantum computation are also discussed.
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On the 15th of April, 1897, a 19 year-old European resident of Baghdad, named Alexander Richard Svoboda, set out on a long journey to Europe by caravan, boat and train. From a large and influential family of merchants, artists, and explorers settled in Ottoman Iraq since the end of the 18th century, Alexander traveled in the company of his parents and a departing British diplomat accompanied by his retinue. They followed a circuitous route through the Middle East to Cairo and thence to Europe on a three and a half month journey which Alexander described day-by-day in a journal written in the Iraqi Arabic of his time.
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Microclimate and host plant architecture significantly influence the abundance and behavior of insects. However, most research in this field has focused at the invertebrate assemblage level, with few studies at the single-species level. Using wild Solanum mauritianum plants, we evaluated the influence of plant structure (number of leaves and branches and height of plant) and microclimate (temperature, relative humidity, and light intensity) on the abundance and behavior of a single insect species, the monophagous tephritid fly Bactrocera cacuminata (Hering). Abundance and oviposition behavior were signficantly influenced by the host structure (density of foliage) and associated microclimate. Resting behavior of both sexes was influenced positively by foliage density, while temperature positively influenced the numbers of resting females. The number of ovipositing females was positively influenced by temperature and negatively by relative humidity. Feeding behavior was rare on the host plant, as was mating. The relatively low explanatory power of the measured variables suggests that, in addition to host plant architecture and associated microclimate, other cues (e.g., olfactory or visual) could affect visitation and use of the larval host plant by adult fruit flies. For 12 plants observed at dusk (the time of fly mating), mating pairs were observed on only one tree. Principal component analyses of the plant and microclimate factors associated with these plants revealed that the plant on which mating was observed had specific characteristics (intermediate light intensity, greater height, and greater quantity of fruit) that may have influenced its selection as a mating site.
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Examines how society allocates support for species’ conservation when numbers involved are large and resources are limited. Rational behaviour suggests that species in urgent need of conservation will receive more support than those species that are common. However, we demonstrate that in the absence of balanced knowledge common species will receive support more than they would otherwise receive despite society placing high existence values on all species. Twenty four species, both common and endangered and some with a restricted distribution, are examined. We demonstrate that balanced information is vital in order to direct more support for species that are endangered than those that are not. Implications for conservation stemming from the findings are discussed.
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In the early 1990's the University of Salford was typical of most pre-1992 Universities in that whilst students provided much of it's income, little attention was paid to pedagogy. As Warren Piper (1994) observed, University teachers were professional in their subject areas but generally did not seek to acquire a pedagogy of HE. This was the case in Alsford. Courses were efficiently run but only a minority of staff were engaged in actively considering learning and teaching issues. Instead staff time was spent on research and commercial activity.----- In the mid-1990's the teaching environment began to change significantly. As well as Dearing, the advent of QAA and teaching quality reviews, Salford was already experiencing changes in the characteristics of its student body. Wideing access was on our agenda before it was so predominant nationally. With increasing numbers and heterogeneity of students as well as these external factors, new challenges were facing the University and teaching domain.----- This paper describes how a culture which values teaching, learning and pedagogic inquiry is being created in the university. It then focuses on parts of this process specific to the Faculty of Business and Informatics, namely the Faculty's Learning and Teaching Research Network and the establishment of the Centre for Construction Education in the School of Construction and Property Management.----- The Faculty of Business and Informatics' Learning and Teaching Research Network aims to raise the profile, quality and volume of pedagogic research across the five schools in the faculty. The initiative is targeted at all academics regardless of previous research experience. We hope to grow and nurture research potential where it exists and to acknowledge and use the existing expertise of subject-based researchers in collaborative ventures. We work on the principle that people are deliged to share what they know but need appreciation and feedback for doing so. A further ain is to surface and celebrate the significant amount of tacit knowledge in the area of pedagogy evidenced by the strength of student and employer feedback in many areas of the faculty's teaching.----- The Faculty embraces generic and core management expertise but also includes applied management disciplines in information systems and construction and property management where internationally leading research activities and networked centres of excellence have been established. Drawing from this experience, and within the context of the Faculty network, a Centre for Construction Education is being established with key international external partners to develop a sustainable business model of an enterprising pedagogic centre that can undertake useful research to underpin teaching in the Faculty whilst offering sustainable business services to allow it to benefit from pump-priming grant funding.----- Internal and external networking are important elements in our plans and ongoing work. Key to this are our links with the LTSN subject centres (BEST and CEBE) and the LTSN generic centre. The paper discusses networking as a concept and gives examples of practices which have proved useful in this context.----- The academic influences on our approach are also examined. Dixon’s (2000) work examining how a range of companies succeed through internal knowledge sharing has provided a range of transferable practices. We also examine the notion of dialogue in this context, defined by Ballantyne (1999) as ‘The interactive human process of reasoning together which comes into being through interactions based on spontaneity or need and is enabled by trust’ Social constructionist principles of Practical Authorship (Shotter, 1993, Pavlica, Holman and Thorpe, 1998)) have also proved useful in developing our perspective on learning and knowledge creation within our community of practice.
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Bomb attacks carried out by terrorists, targeting high occupancy buildings, have become increasingly common in recent times. Large numbers of casualties and property damage result from overpressure of the blast followed by failing of structural elements. Understanding the blast response of multi-storey buildings and evaluating their remaining life have therefore become important. Response and damage analysis of single structural components, such as columns or slabs, to explosive loads have been examined in the literature, but the studies on blast response and damage analysis of structural frames in multi-storey buildings is limited and this is necessary for assessing the vulnerability of them. This paper investigates the blast response and damage evaluation of reinforced concrete (RC) frames, designed for normal gravity loads, in order to evaluate their remaining life. Numerical modelling and analysis were carried out using the explicit finite element software, LS DYNA. The modelling and analysis takes into consideration reinforcement details together and material performance under higher strain rates. Damage indices for columns are calculated based on their residual and original capacities. Numerical results generated in the can be used to identify relationships between the blast load parameters and the column damage. Damage index curve will provide a simple means for assessing the damage to a typical multi-storey building RC frame under an external bomb circumstance.
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This conference is a landmark gathering of those from around the world concerned with the future of Built environment education and Research. It takes place at a time of great change and opportunity. Around the world the long-standing principles of what, how and who we teach for graduate entry into Built environment professions, is increasingly under review. The need for research and the way in which it is funded, conducted and knowledge shared is also under increasing pressure. Both changes are being triggered by a fast changing and increasingly challenging competitive environment for education and research. Competition for the highest quality of graduate entrants in the right numbers is becoming more intense. Competition between Universities, as funding for education and research comes under ever close scrutiny, is intensifying and we are all being forced to look for more effective and exciting ways of recruting, retaining, enhancing and maximising the achievement of our students and of our staff in their research activities. Competition amongst employees in industry is becoming more intense as professional employers increasingly recognise that people and knowledge are their key strategic resources. Universities are increasingly looking to partnerships with industry, the professions and other Universities to further improve their eduacation, research and innovation activities. These challenges are unfolding at a time of accelerating development in information technologies and systems and in our understanding of principles of knowledge management and pedagogical advancement. This environment presents both opportunities and threats to the world of education.
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This paper traces the history of store (retailer-controlled) and national (manufacture controlled)brands; identifies the key historical characteristics of the past 200 years of marketing history;describes the four main time periods of U.S. retail marketing (1800 - 2000); and comments on the most likely developments within the current phases of brand marketing. Will the future focus on technology and new forms of communications? The Internet exemplifies an unconventional retailing environment, with etailer numbers growing rapidly. The central proposition of this paper is that a "cycle of control" - a pattern of marketing developments within the history of retailing and national marketing communications - Can indicate the success of marketing strategies in the future.