909 resultados para SHORT-CONTACT TIMES
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The title-problem has been reduced to that of solving a Fredholm integral equation of the second kind. One end of the cylinder is assumed to be fixed, while the cylinder is deformed by an axial current. The vertical displacement on the upper flat end of the cylinder has been determined from an iterative solution of the Fredholm equation valid for large values of the length. The radial displacement of the curved boundary has also been determined at the middle of the cylinder, by using the iterative solution.
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BACKGROUND Our aim was to ascertain the potential of sulfuryl fluoride (SF) as an alternative fumigant to manage phosphine-resistant pests. We tested the susceptibility of all life stages of red flour beetle, Tribolium castaneum (Herbst), to SF and assessed the presence of cross-resistance to this fumigant in phosphine-resistant strains of this species. RESULTS Analysis of dose–response data indicated that the egg was the stage most tolerant to SF under a 48 h exposure period. At LC50, eggs were 29 times more tolerant than other immature stages and adults, and required a relatively high concentration of 48.2 mg L−1 for complete mortality. No significant differences in tolerance to SF were observed among the three larval instars, pupae and adults, and all of these stages were controlled at a low concentration of 1.32 mg L−1. Phosphine-resistant strains did not show cross-resistance to SF. CONCLUSION Our research concluded that the current maximum registered rate of SF, 1500 gh m−3, is adequate to control all the post-embryonic life stages of T. castaneum over a 48 h fumigation period, but it will fail to achieve complete mortality of eggs, indicating the risk of some survival of eggs under this short exposure period. As there is no cross-resistance to SF in phosphine-resistant insects, it will play a key role in managing phosphine resistance in stored-grain insect pests. © 2014 Commonwealth of Australia. Pest Management Science © 2014 Society of Chemical Industry
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This paper investigates the short-run effects of economic growth on carbon dioxide emissions from the combustion of fossil fuels and the manufacture of cement for 189 countries over the period 1961-2010. Contrary to what has previously been reported, we conclude that there is no strong evidence that the emissions-income elasticity is larger during individual years of economic expansion as compared to recession. Significant evidence of asymmetry emerges when effects over longer periods are considered. We find that economic growth tends to increase emissions not only in the same year, but also in subsequent years. Delayed effects - especially noticeable in the road transport sector - mean that emissions tend to grow more quickly after booms and more slowly after recessions. Emissions are more sensitive to fluctuations in industrial value added than agricultural value added, with services being an intermediate case. On the expenditure side, growth in consumption and growth in investment have similar implications for national emissions. External shocks have a relatively large emissions impact, and the short-run emissions-income elasticity does not appear to decline as incomes increase. Economic growth and emissions have been more tightly linked in fossil-fuel rich countries.
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Bearing area analysis has been used to study the real area of contact and compliance of rough turned steel cylinders in compression. Calculations show that the elastic real area of contact is very small compared to the plastic real area of contact, and that local compliance due to flattening of asperity tips is a small proportion of the total compliance obtained from experiments. The fact that increased load brings more and more new asperities under load rather than enlarging the contact spots leads to a rather simple load-compliance relation for a rough cylinder, viz., W' = Nh · K1δn, where W0 = K1δn defines the load-compliance relation of the individual asperities, and Nh represents the number of asperities bearing the load.
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An important question which has to be answered in evaluting the suitability of a microcomputer for a control application is the time it would take to execute the specified control algorithm. In this paper, we present a method of obtaining closed-form formulas to estimate this time. These formulas are applicable to control algorithms in which arithmetic operations and matrix manipulations dominate. The method does not require writing detailed programs for implementing the control algorithm. Using this method, the execution times of a variety of control algorithms on a range of 16-bit mini- and recently announced microcomputers are calculated. The formulas have been verified independently by an analysis program, which computes the execution time bounds of control algorithms coded in Pascal when they are run on a specified micro- or minicomputer.
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OBJECTIVE To develop a short and easy to use questionnaire to measure use and usability of custom-made orthopaedic shoes, and to investigate its reproducibility. DESIGN Development of the questionnaire (Monitor Orthopaedic Shoes) was based on a literature search, expert interviews, 2 expert meetings, and exploration and testing of reproducibility. The questionnaire comprises 2 parts: a pre part, measuring expectations; and a post part, measuring experiences. Patients The pre part of the final version was completed twice by 37 first-time users before delivery of their orthopaedic shoes. The post part of the final version was completed twice by 39 first-time users who had worn their orthopaedic shoes for 2–4 months. RESULTS High reproducibility scores (Cohen’s kappa > 0.60 or intra class correlation > 0.70) were found in all but one question of both parts of the final version of the Monitor Orthopaedic Shoes questionnaire. The smallest real difference on a visual analogue scale (100 mm) ranged from 21 to 50 mm. It took patients approximately 15 minutes to complete one part. CONCLUSION Monitor Orthopaedic Shoes is a practical and reproducible questionnaire that can measure relevant aspects of use and usability of orthopaedic shoes from a patient’s perspective.
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The purpose of this study is to evaluate contemporary philosophical models for global ethics in light of the Catholic theologian Hans Küng s Global Ethic Project (Projekt Weltethos). Küng s project starts with the motto, No survival without world ethos. No global peace without peace between religions. I will use the philosophically multidimensional potential of Projekt Weltethos in terms of its possible philosophical interpretations to evaluate the general discussion of global ethics within political philosophy today. This is important in its own right, but also because through it, opportunities will emerge to articulate Küng s relatively general argument in a way that leaves less room for mutually contradictory concretizations of what global ethics ultimately should be like. The most important question in this study is the problem of religious and ideological exclusivism and its relation to the ethically consistent articulation of global ethics. I will first explore the question of the role of religion as the basis for ethics in general and what Küng may mean by his claim that only the unconditional can oblige unconditionally. I will reconstruct two different overall philosophical interpretations of the relationship between religious faith and human rationality, each having two different sub-divisions: a liberal interpretation amounts to either a Kantian-Scheiermacherian or a Jaspersian view, whereas what I call postliberal interpretation amounts to either an Aristotelian-Thomistic or an Augustinian view. Thereafter, I will further clarify how Küng views the nature of ethics beyond the question of its principal foundation in religious faith: Küng searches for a middle way between consequentialist and non-consequentialist ethics, a way in which the latter dimension has the final stake. I will then set out to concretize further this more or less general notion of the theoretical potential of Projekt Weltethos in terms of certain precise philosophico-political models. I categorize these models according to their liberal or postliberal orientation. The liberal concretization leads me to consider a wide spectrum of post-Kantian and post-Hegelian models from Rawls to Derrida, while the alternative concretization opens up my ultimate argument in favor of a postliberal type of modus vivendi. I will suggest that the only theoretically and practically plausible way to promote global ethics, in itself a major imperative today, is the recognition of a fundamental and necessary contest between mutually exclusive ideologies in the public sphere. On this basis I will proceed to my postliberal proposal, namely, that a constructive and peaceful encountering of exclusive difference as an ethical vantage point for an intercultural and inter-religious peace dialogue is the most acute challenge for global ethics today.
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Fan forced injection of phosphine gas fumigant into stored grain is a common method to treat infestation by insects. For low injection velocities the transport of fumigant can be modelled as Darcy flow in a porous medium where the gas pressure satisfies Laplace's equation. Using this approach, a closed form series solution is derived for the pressure, velocity and streamlines in a cylindrically stored grain bed with either a circular or annular inlet, from which traverse times are numerically computed. A leading order closed form expression for the traverse time is also obtained and found to be reasonable for inlet configurations close to the central axis of the grain storage. Results are interpreted for the case of a representative 6m high farm wheat store, where the time to advect the phosphine to almost the entire grain bed is found to be approximately one hour.
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A method was developed in the framework of a bistable jump model to obtain the pyrrolidine ring conformations in proline peptides from 13C spin-lattice relaxation times. Equations are presented expressing the ring torsions in terms of the 13C spin-lattice relaxation times of the ring carbons. This method was applied to 26 pyrrolidine ring systems and acceptable conformations were obtained.