998 resultados para ENTROPY GENERATION
Resumo:
Reaction of 6-acetoxy-5-bromomethylquinoline (1c) and 2-bromomethyl-4-(2'-pyridyl)phenyl acetate (2b) with tetrachlorocatechol in acetone in the presence of anhydrous potassium carbonate resulted in the formation of diastereomeric products 3c, 3d, 4e and 4f.
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This paper presents the results of laboratory investigation carried out on Ahmedabad sand on the liquefaction and pore water pressure generation during strain controled cyclic loading. Laboratory experiments were carried out on representative natural sand samples (base sand) collected from earthquake-affected area of Ahmedabad City of Gujarat State in India. A series of strain controled cyclic triaxial tests were carried out on isotropically compressed samples to study the influence of different parameters such as shear strain amplitude, initial effective confining pressure, relative density and percentage of non-plastic fines on the behavior of liquefaction and pore water pressure generation. It has been observed from the laboratory investigation that the potential for liquefaction of the sandy soils depends on the shear strain amplitude, initial relative density, initial effective confining pressure and non-plastic fines. In addition, an empirical relationship between pore pressure ratio and cycle ratio independent of the number of cycles of loading, relative density, confining pressure, amplitude of shear strain and non-plastic fines has been proposed.
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The entire extracellular domain of the human heat-stable enterotoxin (ST) receptor as well as a truncated N-terminal domain were cloned as glutathione S-transferase fusion proteins and expressed in Escherichia coli. The recombinant fusion proteins were purified from both the cytosol and the inclusion body fractions by selective detergent extraction followed by glutathione-agarose affinity chromatography. The purified protein, corresponding to the entire extracellular domain, bound the stable toxin peptide with an affinity comparable to that of the native receptor characterized from the human colonic T84 cell line. No binding was observed with the N-terminal truncated fragment of the receptor under similar conditions, Polyclonal antibodies were raised to the entire extracellular domain fusion protein as well as the truncated extracellular domain fusion protein, and the antibodies were purified by affinity chromatography. Addition of the purified antibodies to T84 cells inhibited ST binding and abolished ST-mediated cGMP production, indicating that critical epitopes involved in ligand interaction are present in the N-terminal fragment of the receptor, Purified antibodies recognized a single protein of M(r) 160,000 Da on Western blotting with T84 membranes, corresponding to a size of the native glycosylated receptor in T84 cells. These studies are the first report of the expression, purification, and characterization of any member of the guanylyl cyclase family of receptors in E. coli and show that binding of the toxin to the extracellular domain of the receptor is possible in the absence of any posttranslational modifications such as glycosylation. The recombinant fusion proteins as well as the antibodies that we have generated could serve as useful tools in the identification of critical residues of the extracellular domain involved in ligand interaction.
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The correlation dimension D 2 and correlation entropy K 2 are both important quantifiers in nonlinear time series analysis. However, use of D 2 has been more common compared to K 2 as a discriminating measure. One reason for this is that D 2 is a static measure and can be easily evaluated from a time series. However, in many cases, especially those involving coloured noise, K 2 is regarded as a more useful measure. Here we present an efficient algorithmic scheme to compute K 2 directly from a time series data and show that K 2 can be used as a more effective measure compared to D 2 for analysing practical time series involving coloured noise.
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In a search for inorganic oxide materials showing second-order nonlinear optical (NLO) susceptibility, we investigated several berates, silicates, and a phosphate containing trans-connected MO6, octahedral chains or MO5 square pyramids, where, M = d(0): Ti(IV), Nb(V), or Ta(V), Our investigations identified two new NLO structures: batisite, Na2Ba(TiO)(2)Si4O12, containing trans-connected TiO5 octahedral chains, and fresnoite, Ba2TiOSi2O7, containing square-pyramidal TiO5. Investigation of two other materials containing square-pyramidal TiO5 viz,, Cs2TiOP2O7 and Na4Ti2Si8O22. 4H(2)O, revealed that isolated TiO5, square pyramids alone do not cause a second harmonic generation (SHG) response; rather, the orientation of TiO5 units to produce -Ti-O-Ti-O- chains with alternating long and short Ti-O distances in the fresnoite structure is most likely the origin of a strong SHG response in fresnoite,
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The world is rich with information such as signage and maps to assist humans to navigate. We present a method to extract topological spatial information from a generic bitmap floor plan and build a topometric graph that can be used by a mobile robot for tasks such as path planning and guided exploration. The algorithm first detects and extracts text in an image of the floor plan. Using the locations of the extracted text, flood fill is used to find the rooms and hallways. Doors are found by matching SURF features and these form the connections between rooms, which are the edges of the topological graph. Our system is able to automatically detect doors and differentiate between hallways and rooms, which is important for effective navigation. We show that our method can extract a topometric graph from a floor plan and is robust against ambiguous cases most commonly seen in floor plans including elevators and stairwells.
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In this paper, we have probed the origin of SHG in copper nanoparticles by polarization-resolved hyper-Rayleigh scattering (HRS). Results obtained with various sizes of copper nanoparticles at four different wavelengths covering the wavelength range 738-1907 nm reveal that the origin of second harmonic generation (SHG) in these particles is purely dipolar in nature as long as the size (d) of the particles remains smaller compared to the wavelength (;.) of light ("small-particle limit"). However, contribution of the higher order multipoles coupled with retardation effect becomes apparent with an increase in the d/lambda ratio. We have identified the "small-particle limit" in the second harmonic generation from noble metal nanoparticles by evaluating the critical d/lambda ratio at which the retardation effect sets in the noble metal nanoparticles. We have found that the second-order nonlinear optical property of copper nanoparticles closely resembles that of gold, but not that of silver. (C) 2009 Elsevier B.V. All rights reserved.
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This research is about jazz in Chile in relation to modernity and identity. Final chapters focus and detach latest jazz musician s generation in 1990 decade and composer guitarist Angel Parra. An historic and sociological approach is developed, which will be useful for modernity and identity analysis, and so on post modernity and globalization. Modernity has been studied in texts of Adorno, Baudrillard, Brünner, García Canclini, Habermas and Jameson. Identity has been studied in texts of Aharonián, Cordúa, Garretón, Gissi, Larraín and others. Chapter 3 is about Latin-American musicology and jazz investigations, in relation to approach developed in chapter 2. Chapters 4 and 5 are about history of jazz in Chile until beginning of XXI century. Chapter 6 focuses in Ángel Parra Orrego. Conclusions of this investigation detach the modernist mechanical that has conducted jazz development in Chile, which in Ángel Parra´s case has been overcame by a post modernist behaviour. This behaviour has solved in a creative way, subjects like modernity and identity in jazz practice in a Latin-American country.
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Through an analysis using the transfer function of a pinhole camera, the multiple imaging characteristics of photographic diffusers described by Grover and Tremblay [Appl. Opt.21,4500(1982)] is studied. It is found that only one pinhole diameter satisfies the optimum imaging condition for best contrast transfer at any desired spatial frequency. A simple method of generating random pinhole arrays with a controlled pinhole diameter is described. These pinhole arrays are later used to generate high frequency sinusoidal gratings from a coarse grid. The contrast in the final gratings is found to be reasonably high.
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This report summarises the findings of a case study on Queensland’s New Generation Rollingstock (NGR) Project carried out as part of SBEnrc Project 2.34 Driving Whole-of-life Efficiencies through BIM and Procurement. This case study is one of three exemplar projects studied in order to leverage academic research in defining indicators for measuring tangible and intangible benefits of Building Information Modelling (BIM) across a project’s life-cycle in infrastructure and buildings. The NGR is an AUD 4.4 billion project carried out under an Availability Payment Public-Private Partnership (PPP) between the Queensland Government and the Bomabardier-led QTECTIC consortium comprising Bombardier Transportation, John Laing, ITOCHU Corporation and Aberdeen Infrastructure Investments. BIM has been deployed on the project from conceptual stages to drive both design and the currently ongoing construction at the Wulkuraka Project Site. This case study sourced information from a series of semi-structured interviews covering a cross-section of key stakeholders on the project. The present research identified 25 benefits gained from implementing BIM processes and tools. Some of the most prominent benefits were those leading to improved outcomes and higher customer satisfaction such as improved communications, data and information management, and coordination. There were also a number of expected benefits for future phases such as: • Improved decision making through the use of BIM for managing assets • Improved models through BIM maturity • Better utilisation of BIM for procurement on similar future projects • New capacity to specify the content of BIM models within contracts There were also three benefits that were expected to have been achieved but were not realised on the NGR project. These were higher construction information quality levels, better alignment in design teams as well as project teams, and capability improvements in measuring the impact of BIM on construction safety. This report includes individual profiles describing each benefit as well as the tools and processes that enabled them. Four key BIM metrics were found to be currently in use and six more were identified as potential metrics for the future. This case study also provides insights into challenges associated with implementing BIM on a project of the size and complexity of the NGR. Procurement aspects and lessons learned for managers are also highlighted, including a list of recommendations for developing a framework to assess the benefits of BIM across the project life-cycle.
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Knowledge of the generation of H202 in cellular oxidations has existed for many years. It has been assumed that H202 is tOxiC tO cells and the presence of catalase is indicative of a detoxication mechanism. Other radicals of oxygen were recently recognized to be more potent destructive agents of biological material than H202. Also catalase and other peroxidases utilize H202 in some cellular oxidation processes leading to several important metabolites. Thus, the generation of H202 in cellular processes seems to be purposeful and H202 can not be dismissed as a mere undesirable byproduct. Biological formation of H202 is not limited to the previously known flavoproteins and some copper enzymes, but other redox systems, particularly heme and non-heme iron proteins, are now found to undergo auto-oxidation yielding H202. The capacity for generation of H202 is now found to be widespread in a variety of organisms and in the organdies of the cells. The reduction of oxygen to H20 by mitochondrial cytochrome oxidase being the predominant oxygen-utilizing reaction had over-shadowed the importance of the quantitatively minor pathways. Under aerobic conditions generation of H202 by a Variety of biomembranes has now been found to be a physiological event interlinked with phenomena such as phagocytosis, transport processes and thermogenesis in some as yet unidentified way. The underlying mechanisms of these processes seem to involve generation and utilization of H202 in mitochondria, microsomes, peroxisomes or plasma membranes. This review gives an account of the potential of biomembranes to generate H202 and its implication in the cellular processes.
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This thesis is a study of Chinese One Child Generation's digital and social sharing. It examines urban youth grassroots communities, including an urban farmers' community and volunteers in educational camps. These case studies explain the emergence of 'sharism' in reaction to the growing risks in China, such as food safety and environmental degradation emanating from China's rapid economic development, and growing urbanism, globalisation, and consumerism. The new forms of 'sharism' are linked to guanxi (social relations) and connected youth communities, which are made possible by increasing accessibility to digital and networked technologies.
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[Excerpt] In response to the longstanding and repeated criticisms that HR does not add value to organizations, the past 10 years has seen a burgeoning of research attempting to demonstrate that progressive HR practices result in higher organizational performance. Huselid’s (1995)groundbreaking study demonstrated that a set of HR practices he referred to as High Performance Work Systems (HPWS) were related to accounting profits and market value of firms. Since then, a number of studies have shown similar positive relationships between HR practices and various measures of firm performance. While the studies comprising what I refer to as “first generation SHRM research” have added to what is becoming a more convincing body of evidence of the positive relationship between HR and performance, this body tends to lack sufficient data to demonstrate that the relationship is actually causal in the sense that HR practices, when instituted, lead to higher performance. This next generation of SHRM research will begin (and, in fact has begun) to focus on designing more rigorous tests of the hypothesis that employing progressive HRM systems actually results in higher organizational performance. This generation of research will focus on two aspects: demonstrating the HRM value chain, and proving causality as opposed to merely covariation.
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This study examines supervisors' emerging new role in a technical customer service and home customers division of a large Finnish telecommunications corporation. Data of the study comes from a second-generation knowledge management project, an intervention research, which was conducted for supervisors of the division. The study exemplifies how supervision work is transforming in high technology organization characterized with high speed of change in technologies, products, and in grass root work practices. The intervention research was conducted in the division during spring 2000. Primary analyzed data consists of six two-hour videorecorded intervention sessions. Unit of analysis has been collective learningactions. Researcher has first written conversation transcripts out of the video-recorded meetings and then analyzed this qualitative data using analytical schema based on collective learning actions. Supervisors' role is conceptualized as an actor of a collective and dynamic activity system, based on the ideas from cultural historical activity theory. On knowledge management researcher has takena second-generation knowledge management viewpoint, following ideas fromcultural historical activity theory and developmental work research. Second-generation knowledge management considers knowledge embedded and constructed in collective practices, such as innovation networks or communities of practice (supervisors' work community), which have the capacity to create new knowledge. Analysis and illustration of supervisors' emerging new role is conceptualized in this framework using methodological ideas derived from activity theory and developmental work research. Major findings of the study show that supervisors' emerging new role in a high technology telecommunication organization characterized with high speed of discontinuous change in technologies, products, and in grass-root practices cannot be defined or characterized using a normative management role/model. Their role is expanding two-dimensionally, (1) socially and (2) in new knowledge, and work practices. The expansion in organization and inter-organizational network (social expansion) causes pressures to manage a network of co-operation partners and subordinates. On the other hand, the faster speed of change in technological solutions, new products, and novel customer wants (expansion in knowledge) causes pressures for supervisors to innovate quickly new work practices to manage this change. Keywords: Activity theory, knowledge management, developmental work research, supervisors, high technology organizations, telecommunication organizations, second-generation knowledge management, competence laboratory, intervention research, learning actions.
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Large integration of solar Photo Voltaic (PV) in distribution network has resulted in over-voltage problems. Several control techniques are developed to address over-voltage problem using Deterministic Load Flow (DLF). However, intermittent characteristics of PV generation require Probabilistic Load Flow (PLF) to introduce variability in analysis that is ignored in DLF. The traditional PLF techniques are not suitable for distribution systems and suffer from several drawbacks such as computational burden (Monte Carlo, Conventional convolution), sensitive accuracy with the complexity of system (point estimation method), requirement of necessary linearization (multi-linear simulation) and convergence problem (Gram–Charlier expansion, Cornish Fisher expansion). In this research, Latin Hypercube Sampling with Cholesky Decomposition (LHS-CD) is used to quantify the over-voltage issues with and without the voltage control algorithm in the distribution network with active generation. LHS technique is verified with a test network and real system from an Australian distribution network service provider. Accuracy and computational burden of simulated results are also compared with Monte Carlo simulations.