955 resultados para Sphere packings
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In recent years structured packings have become more widely used in the process industries because of their improved volumetric efficiency. Most structured packings consist of corrugated sheets placed in the vertical plane The corrugations provide a regular network of channels for vapour liquid contact. Until recently it has been necessary to develop new packings by trial and error, testing new shapes in the laboratory. The orderly repetitive nature of the channel network produced by a structured packing suggests it may be possible to develop improved structured packings by the application of computational fluid dynamics (CFD) to calculate the packing performance and evaluate changes in shape so as to reduce the need for laboratory testing. In this work the CFD package PHOENICS has been used to predict the flow patterns produced in the vapour phase as it passes through the channel network. A particular novelty of the approach is to set up a method of solving the Navier Stokes equations for any particular intersection of channels. The flow pattern of the streams leaving the intersection is then made the input to the downstream intersection. In this way the flow pattern within a section of packing can be calculated. The resulting heat or mass transfer performance can be calculated by other standard CFD procedures. The CFD predictions revealed a circulation developing within the channels which produce a loss in mass transfer efficiency The calculations explained and predicted a change in mass transfer efficiency with depth of the sheets. This effect was also shown experimentally. New shapes of packing were proposed to remove the circulation and these were evaluated using CFD. A new shape was chosen and manufactured. This was tested experimentally and found to have a higher mass transfer efficiency than the standard packing.
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A new generalized sphere decoding algorithm is proposed for underdetermined MIMO systems with fewer receive antennas N than transmit antennas M. The proposed algorithm is significantly faster than the existing generalized sphere decoding algorithms. The basic idea is to partition the transmitted signal vector into two subvectors x and x with N - 1 and M - N + 1 elements respectively. After some simple transformations, an outer layer Sphere Decoder (SD) can be used to choose proper x and then use an inner layer SD to decide x, thus the whole transmitted signal vector is obtained. Simulation results show that Double Layer Sphere Decoding (DLSD) has far less complexity than the existing Generalized Sphere Decoding (GSDs).
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We define Picard cycles on each smooth three-sheeted Galois cover C of the Riemann sphere. The moduli space of all these algebraic curves is a nice Shimura surface, namely a symmetric quotient of the projective plane uniformized by the complex two-dimensional unit ball. We show that all Picard cycles on C form a simple orbit of the Picard modular group of Eisenstein numbers. The proof uses a special surface classification in connection with the uniformization of a classical Picard-Fuchs system. It yields an explicit symplectic representation of the braid groups (coloured or not) of four strings.
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Methodological, theoretical and technological bases of the new branch standard of Ukraine higher education which regulates preparation process of masters - professionals in the information area and information analysts are considered. The new systemological knowledge-oriented technologies developed in KNURE which considerably surpass foreign analogues are put as the basis of training.
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The logic of ‘time’ in modern capitalist society appears to be a fixed concept. Time dictates human activity with a regularity, which as long ago as 1944, George Woodcock referred to as The Tyranny of the Clock. Seventy years on, Hartmut Rosa suggests humans no longer maintain speed to achieve something new, but simply to preserve the status quo, in a ‘social acceleration’ that is lethal to democracy. Political engagement takes time we no longer have, as we rush between our virtual spaces and ‘non-places’ of higher education. I suggest it’s time to confront the conspirators that, in partnership with the clock, accelerate our social engagements with technology in the context of learning. Through Critical Discourse Analysis (CDA) I reveal an alarming situation if we don’t. With reference to Bauman’s Liquid Modernity, I observe a ‘lightness’ in policy texts where humans have been ‘liquified’ Separating people from their own labour with technology in policy maintains the flow of speed a neoliberal economy demands. I suggest a new ‘solidity’ of human presence is required as we write about networked learning. ‘Writing ourselves back in’ requires a commitment to ‘be there’ in policy and provide arguments that decelerate the tyranny of time. I am though ever-mindful that social acceleration is also of our own making, and there is every possibility that we actually enjoy it.
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The focus of this paper is brand destruction, however in a slightly different sense than the traditional marketing literature depicts it. The concept of brand destruction basically tends to be discussed either (1) as an accidental, counter-productive event in a campaign which leads to the ruining of the brand, or (2) an intentional act by competitors in the market, which results the same breakdown mentioned above. As this paper shows, there are other ways to consider as well, when speaking about brand destruction. An often overlooked type of brand destruction is a rather new phenomenon: destroying the brand by customers or business partners. The adequate scene for this case is the internet itself, especially different social media platforms, e. g. Facebook, Twitter, Tumblr, Instagram, etc. Also popular weblogs can play an important role in brand destruction made by customers or business partners (general cases related to social media are depicted in Lipsman – Mud – Rich – Bruich, 2012). This paper presents a couple of cases in the online field and focuses basically on online communicative activities, in which a brand’s negative properties come to discussion. Both Hungarian and foreign examples are easy to find and they all demonstrate the growing power of consumers. This observation led marketing experts to start talking about the ‘smooth seizure of power by consumers’. Whilst the critic of this concept is considered to be relevant, this paper describes the elements and methods of the ‘seizure’ – from an online social point of view. The key of handling brand destruction cases efficiently lies in the role of social media users. They are not only consumers, but the opportunity for producing online contents is in their hands as well – this fact results in the idea of ‘prosumers’. Thus customers on social media platforms must be handled as a ‘critical mass’: as civic warriors with strong weapons in their armoury. No companies are allowed to feel safe, as the slightest error may well be punished by the crowd.
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Empirikus vizsgálatok szerint a vállalatok fejlesztési törekvéseit Magyarországon is elsősorban a piaci kilátások határozzák meg, a finanszírozási körülmények szerepe jóval gyengébb. A beruházások és innovációk végrehajtása elsősorban a műszaki végzettségűek iránti keresletet növelheti, a szakképzetlen dolgozók körében viszont gyakran leépítésekre vezet. A vállalatok igénye és az állást keresők kompetenciái azonban nemcsak a szakmastruktúrában térnek el. A korábban megvalósított fejlesztéseknek a válság idején munkahelymegtartó szerepe volt. A jövőbeni fejlesztések munkaerőigényének kielégítésében mind az üzleti szektor szereplőinek, mind a szakpolitikáknak fontos tennivalói vannak. _______ According to recent empirical research development efforts of companies in Hungary are primarily determined by the market outlook, the role of financing conditions is much weaker. Implementation of investments and innovation can increase in first row the demand for technical professionals and often causes dismissals in unskilled labour. The demand of companies and competences of job seekers diverge not only in the professional structure. Earlier fulfilled development had workplace keeping role during the recession. Both actors of business sector and policies have important tasks to do in satisfying labour demand of future developments.
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The maturation of the public sphere in Argentina during the late nineteenth and early twentieth centuries was a critical element in the nation-building process and the overall development of the modern state. Within the context of this evolution, the discourse of disease generated intense debates that subsequently influenced policies that transformed the public spaces of Buenos Aires and facilitated state intervention within the private domains of the city’s inhabitants. Under the banner of hygiene and public health, municipal officials thus Europeanized the nation’s capital through the construction of parks and plazas and likewise utilized the press to garner support for the initiatives that would remedy the unsanitary conditions and practices of the city. Despite promises to the contrary, the improvements to the public spaces of Buenos Aires primarily benefited the porteño elite while the efforts to root out disease often targeted working-class neighborhoods. The model that reformed the public space of Buenos Aires, including its socially differentiated application of aesthetic order and public health policies, was ultimately employed throughout the Argentine Republic as the consolidated political elite rolled out its national program of material and social development.
Humanitarian charter and minimum standards in humanitarian response. The Sphere Project [Annotation]
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Journalist Helen Aguirre Ferre lectures on the subject of the humanities in the public sphere in South Florida. Event held at the Green Library, Modesto Maidique Campus, Florida International University, on February 6, 2013.
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The purpose of this study was to create a scale that could measure compartmentalization. In the first of two studies 311 working undergraduates were asked to indicate agreement with 119 items that measured compartmentalization. The resulting scale's reliability and validity were evaluated by having a second sample of 312 working students complete the items that comprise a sphere overlap scale, two measures of spillover, and a measure of personality, coping, and demoralization. Although the study's original goal was not realized, its procedures were successful in developing a short (10-item) measure of work-to-home spillover whose items loaded on a single factor. Structural equation modeling indicated that SOS items were correlated with existing measures of spillover and could be discriminated from related concepts of personality and coping. The SOS was also more highly correlated with demoralization than existing measures of spillover in hierarchical analyses that controlled for demographic factors, personality characteristics, and coping style. It is concluded that the SOS shows enough promise to warrant the cost of its appraisal as an alternative measure of spillover in a longitudinal study.