980 resultados para open course


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By means of CNDO/2 calculations on N-methyl acetamide, it is shown that the state of minimum energy of the trans-peptide unit is a non-planar conformation, with the NH and NC2α bonds being significantly out of the plane formed by the atoms C1α, C′, O and N.

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We use the Lippman-Schwinger scattering theory to study nonequilibrium electron transport through an interacting open quantum dot. The two-particle current is evaluated exactly while we use perturbation theory to calculate the current when the leads are Fermi liquids at different chemical potentials. We find an interesting two-particle resonance induced by the interaction and obtain criteria to observe it when a small bias is applied across the dot. Finally, for a system without spatial inversion symmetry, we find that the two-particle current is quite different depending on whether the electrons are incident from the left or the right lead.

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Cesium hydrogen l-malate monohydrate, CsH(C4H4O5)·H2O, is a new chiral open-framework semi-organic crystalline material with a second-harmonic generation efficiency one order of magnitude greater than KDP. Single crystals of this new material have been grown by the conventional slow cooling technique from aqueous solution. Grown crystals display both platy and prismatic morphologies depending on the imposed supersaturation. Hardness values measured using Vickers hardness indenter show considerable anisotropy. The resistivity behavior at room temperature and above, places the crystal between an ionic conductor and a dielectric. The single-crystal SHG efficiency estimated through Maker fringes experiment gives deff which is 4.24 times that of KDP. Single and multiple shot experiments performed on the grown crystals for the fundamental and second harmonic of pulsed Nd:YAG laser (1064 and 532 nm) show that it exhibits a high laser damage threshold which is a favorable property for nonlinear optical applications.

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Vertebrate fauna was studied over 10 years following revegetation of a Eucalyptus tereticornis ecosystem on former agricultural land. We compared four vegetation types: remnant forest, plantings of a mix of native tree species on cleared land, natural regeneration of partially cleared land after livestock removal, and cleared pasture land with scattered paddock trees managed for livestock production. Pasture differed significantly from remnant in both bird and nonbird fauna. Although 10 years of ecosystem restoration is relatively short term in the restoration process, in this time bird assemblages in plantings and natural regeneration had diverged significantly from pasture, but still differed significantly from remnant. After 10 years, 70 and 66% of the total vertebrate species found in remnant had been recorded in plantings and natural regeneration, respectively. Although the fauna assemblages within plantings and natural regeneration were tracking toward those of remnant, significant differences in fauna between plantings and natural regeneration indicated community development along different restoration pathways. Because natural regeneration contained more mature trees (dbh > 30 cm), native shrub species, and coarse woody debris than plantings from the beginning of the study, these features possibly encouraged different fauna to the revegetation areas from the outset. The ability of plantings and natural regeneration to transition to the remnant state will be governed by a number of factors that were significant in the analyses, including shrub cover, herbaceous biomass, tree hollows, time since fire, and landscape condition. Both active and passive restoration produced significant change from the cleared state in the short term.

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This paper focuses on the advantages of Open Access, (OA) particularly from the point of view of individual researchers, research centres and disciplines, and institutions. The advantage described by the phrase “OA advantage”, is multifaceted. The experience of Queensland University of Technology in Australia in pioneering OA as preferred practice in an institution with a growing research profile and energy, has seen evidence of the OA advantage develop in the experience of our researchers. The University has witnessed the development of practical evidence about improved recognition and impact, and this has occurred in the context of sector wide activity and policy where fresh approaches and leadership will result in even greater rewards for researchers whose outputs are “in the open”.

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On interrupting polarisation, the magnesium anode exhibits a negative overshoot in potential followed by a slow recovery to a steady state value. A model has been proposed to explain the opencircuit potential-time transient in terms of a spontaneous passivation of the metal and the consequent changes in the corrosion potential. Theoretical expressions have been derived for the timedependence of the open-circuit electrode potential. Calculated, potential-time curves thus obtained are in qualitative agreement with experimental data. A possible application of this phenomenon to develop non-destructive quality control tests of Mg, Li and Al-based dry cells has been pointed out.

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L-Lysine d-pantothenate, a 1:1 amino acid-vitamin complex, crystallizes in the monoclinic space group P21 with Image Full-size image (1K) .The structure has been solved by direct methods and refined to an R value of 0.053 for 1868 observed reflections. The zwitterionic positively charged lysine molecules in the structure assume the sterically most favourable conformation with an all-trans side chain trans to the α-carboxylate group. The pantothenate anion has a somewhat folded conformation stabilised by an intramolecular bifurcated hydrogen bond. The unlike molecules aggregate into separate alternating layers. The molecules in the lysine layers form a head-to-tail sequence parallel to the a-axis. The interactions which hold the adjacent layers together include those between the side chain amino group of lysine and the carboxylate group in the pantothenate anion. The geometry of these interactions is such that each carboxylate group is sandwiched between two amino groups in a periodic arrangement of alternating carboxylate and amino groups.

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Free and Open Source Software (FOSS) has gained increased interest in the computer software industry, but assessing its quality remains a challenge. FOSS development is frequently carried out by globally distributed development teams, and all stages of development are publicly visible. Several product and process-level quality factors can be measured using the public data. This thesis presents a theoretical background for software quality and metrics and their application in a FOSS environment. Information available from FOSS projects in three information spaces are presented, and a quality model suitable for use in a FOSS context is constructed. The model includes both process and product quality metrics, and takes into account the tools and working methods commonly used in FOSS projects. A subset of the constructed quality model is applied to three FOSS projects, highlighting both theoretical and practical concerns in implementing automatic metric collection and analysis. The experiment shows that useful quality information can be extracted from the vast amount of data available. In particular, projects vary in their growth rate, complexity, modularity and team structure.

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This thesis addresses audience engagement challenges during professional mainstream ballet and contemporary dance company performances by examining spectator-dancer relationships. Focusing on the open rehearsal as an audience engagement tool, this project presents a new line of enquiry in dance reception studies. The findings signify that open rehearsal attendance can contribute to more meaningful and enjoyable performance experiences for audience members by opening up the possibility of different relationships with dancers.

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Recolonisation of soil by macrofauna (especially ants, termites and earthworms) in rehabilitated open-cut mine sites is inevitable and, in terms of habitat restoration and function, typically of great value. In these highly disturbed landscapes, soil invertebrates play a major role in soil development (macropore configuration, nutrient cycling, bioturbation, etc.) and can influence hydrological processes such as infiltration, seepage, runoff generation and soil erosion. Understanding and quantifying these ecosystem processes is important in rehabilitation design, establishment and subsequent management to ensure progress to the desired end goal, especially in waste cover systems designed to prevent water reaching and transporting underlying hazardous waste materials. However, the soil macrofauna is typically overlooked during hydrological modelling, possibly due to uncertainties on the extent of their influence, which can lead to failure of waste cover systems or rehabilitation activities. We propose that scientific experiments under controlled conditions and field trials on post-mining lands are required to quantify (i) macrofauna–soil structure interactions, (ii) functional dynamics of macrofauna taxa,and (iii) their effects on macrofauna and soil development over time. Such knowledge would provide crucial information for soil water models, which would increase confidence in mine waste cover design recommendations and eventually lead to higher likelihood of rehabilitation success of open-cut mining land.

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This study presents a comprehensive mathematical formulation model for a short-term open-pit mine block sequencing problem, which considers nearly all relevant technical aspects in open-pit mining. The proposed model aims to obtain the optimum extraction sequences of the original-size (smallest) blocks over short time intervals and in the presence of real-life constraints, including precedence relationship, machine capacity, grade requirements, processing demands and stockpile management. A hybrid branch-and-bound and simulated annealing algorithm is developed to solve the problem. Computational experiments show that the proposed methodology is a promising way to provide quantitative recommendations for mine planning and scheduling engineers.

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Free and open source software development is an alternative to traditional software engineering as an approach to the development of complex software systems. It is a way of developing software based on geographically distributed teams of volunteers without apparent central plan or traditional mechanisms of coordination. The purpose of this thesis is to summarize the current knowledge about free and open source software development and explore the ways on which further understanding on it could be gained. The results of research on the field as well as the research methods are introduced and discussed. Also adapting software process metrics to the context of free and open source software development is illustrated and the possibilities to utilize them as tools to validate other research are discussed.

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During the treatment of diabetic Charcot neuroarthropathy (CN) of the foot in two young patients, we discovered atypical alterations of their hands with loss of strength and paresthesia combined with atypical and nonhealing bone alterations and instability. Whereas CN of the foot is a serious and well-known complication of diabetes, CN of the hand is only mentioned in four articles (1–4).

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The purpose of my research is to inquire into the essence and activity of God in the legendarium of the English philologist and writer J.R.R. Tolkien (1892-1973). The legendarium, composed of Tolkien’s writings related to Middle-earth, was begun when he created two Elvish languages, Quenya based on Finnish, Sindarin based on Welsh. Tolkien developed his mythology inspired by Germanic myths and The Kalevala. It is a fictional ancient history set in our world. The legendarium is monotheistic: God is called Eru ‘The One’ and Ilúvatar ‘Father of All’. Eru is the same as the Christian God, for Tolkien wanted to keep his tales consistent with his faith. He said his works were Christian by nature, with the religious element absorbed into the story and the symbolism. In The Silmarillion, set in the primeval ages of Middle-earth, the theological aspects are more conspicuous, while in The Lord of the Rings, which brings the stories to an end, they are mostly limited to symbolic references. The legendarium is unified by its realistic outlook on creaturely abilities and hope expressing itself as humbly defiant resistance. ”The possibility of complexity or of distinctions in the nature of Eru” is a part of the legendarium. Eru Ilúvatar is Trinitarian, as per Tolkien’s faith. Without contextual qualifiers, Eru seems to refer to God the Father, like God in the Bible. Being the creator who dwells outside the world is attributed to Him. The Holy Spirit is the only Person of the Trinity bestown with names: the Flame Imperishable and the Secret Fire. When Eru creates the material world with His word, He sends the Flame Imperishable to burn at the heart of the world. The Secret Fire signifies the Creative Power that belongs to God alone, and is a part of Him. The Son, the Word, is not directly mentioned, but according to one writing Eru must step inside the world in order to save it from corruption, yet remain outside it at the same time. The inner structure of the legendarium refers to the need for a future salvation. The creative word of Eru, “Eä! Let these things Be!”, probably has a connection with the Logos in Christianity. Thus we can find three “distinctions” in Eru: a Creator who dwells outside the world, a Sustainer who dwells inside it and a Redeemer who shall step inside it. Some studies of Tolkien have claimed that Eru is distant and remote. This seems to hold water only partially. Ilúvatar, the Father of All, has a special relation with the Eruhíni, His Children, the immortal Elves and the mortal Men. He communicates with them directly only through the Valar, who resemble archangels. Nevertheless, only the Children of Eru can fight against evil, because their tragic fortunes turn evil into good. Even though religious activities are scarce among them, the fundamental faith and ultimate hope of the “Free Peoples” is directed towards Eru. He is present in the drama of history as the “Author of the Story”, who at times also interferes with its course through catastrophes and eucatastrophes, ‘good catastrophes’. Eru brings about a catastrophe when evil would otherwise bring good to an end, and He brings about a eucatasrophe when creaturely strength is not sufficent for victory. Victory over corruption is especially connected with mortal Men, of whom the most (or least) insignificant people are the Hobbits. However, because of the “primeval disaster” (that is, fall) of Mankind, ultimate salvation can only remain open, a hope for the far future.