990 resultados para Alfred (18..-19..) -- Portraits
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The static response of thin, wrinkled membranes is studied using both a tension field approximation based on plane stress conditions and a 3D nonlinear elasticityformulation, discretized through 8-noded Cosserat point elements. While the tension field approach only obtains the wrinkled/slack regions and at best a measure of the extent of wrinkliness, the 3D elasticity solution provides, in principle, the deformed shape of a wrinkled/slack membrane. However, since membranes barely resist compression, the discretized and linearized system equations via both the approaches are ill-conditioned and solutions could thus be sensitive to discretizations errors as well as other sources of noises/imperfections. We propose a regularized, pseudo-dynamical recursion scheme that provides a sequence of updates, which are almost insensitive to theregularizing term as well as the time step size used for integrating the pseudo-dynamical form. This is borne out through several numerical examples wherein the relative performance of the proposed recursion scheme vis-a-vis a regularized Newton strategy is compared. The pseudo-time marching strategy, when implemented using 3D Cosserat point elements, also provides a computationally cheaper, numerically accurate and simpler alternative to that using geometrically exact shell theories for computing large deformations of membranes in the presence of wrinkles. (C) 2010 Elsevier Ltd. All rights reserved.
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The aim of this study was to examine the trends, incidence and recidivism of drunken driving during a 20-year period (1988 - 2007) using the data on all suspected drunken driving in this period. Furthermore, the association between social background and drunken driving, and the mortality of drunk drivers were studied by using administrative register data provided by Statistics Finland. The study was completely register-based. In 1989 - 1991, every year 30,000 drivers were suspected of drunken driving, but the number fell to less than 20,000 by 1994, during the economic recession. The changes in the arrest incidence of the youngest age groups were especially pronounced, most of all in the age group of 18 - 19-year olds. Even though the incidence among youth decreased dramatically, their incidence rate was still twice that of the general population aged 15 - 84 years. Drunken driving was associated with a poor social background among youth and working-aged men and women. For example, a low level of education, unemployment, divorce, and parental factors in youth were associated with a higher risk of being arrested for drunken driving. While a low income was related to more drunken driving among working-aged people, the effect among young persons was the opposite. Every third drunk driver got rearrested during a 15-year period, whereas the estimated rearrest rate was 44%. Findings of drugs only or in combination with alcohol increased the risk of rearrest. The highest rearrest rates were seen among drivers who were under the influence of amphetamines or cannabis. Also male gender, young age, high blood alcohol concentration, and arrest during weekdays and in the daytime predicted rearrest. When compared to the general population, arrested drunk drivers had significant excess mortality. The greatest relative differences were seen in alcohol-related causes of death (including alcohol diseases and alcohol poisoning), accidents, suicides and violence. Also mortality due to other than alcohol-related diseases was elevated among drunk drivers. Drunken driving was associated with multiple factors linked to traffic safety, health and social problems. Social marginalization may expose a person to harmful use of alcohol and drunken driving, and the associations are seen already among the youth. Recidivism is common among drunk drivers, and driving under the influence of illicit and/or medicinal drugs is likely to indicate worse substance abuse problems, judging from the high rearrest rates. High alcohol-related mortality in this population shows that drunken driving is clearly an indicator of alcohol abuse. More effective measures of preventing alcohol-related harms are needed, than merely preventing convicted drunk drivers from driving again.
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Novel cationic and neutral analogues of bile acids (1-6) were synthesized and their aggregation properties studied. Cations 1 and 2 formed thermoreversible gels in aqueous salt solutions, whereas neutral 4 formed gels in water in the presence of organic solvents such as ethanol, methanol, DMSO, and DMF. The gels derived from 1 and 4 have been investigated by SEM and with pyrene as a fluorescent probe.
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A two-dimensional finite difference model, which solves mixed type of Richards' equation, whose non-linearity is dealt with modified Picard's iteration and strongly implicit procedure to solve the resulting equations, is presented. Modeling of seepage flow through heterogeneous soils, which is common in the field is addressed in the present study. The present model can be applied to both unsaturated and saturated soils and can handle very dry initial condition and steep wetting fronts. The model is validated by comparing experimental results reported in the literature. Newness of this two dimensional model is its application on layered soils with transient seepage face development, which has not been reported in the literature. Application of the two dimensional model for studying unconfined drainage due to sudden drop of water table at seepage face in layered soils is demonstrated. In the present work different sizes of rectangular flow domain with different types of layering are chosen. Sensitivity of seepage height due to problem dimension of layered system is studied. The effect of aspect ratio on seepage face development in case of the flow through layered soil media is demonstrated. The model is also applied to random heterogeneous soils in which the randomness of the model parameters is generated using the turning band technique. The results are discussed in terms of phreatic surface and seepage height development and also flux across the seepage face. Such accurate modeling of seepage face development and quantification of flux moving across the seepage face becomes important while modeling transport problems in variably saturated media.
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This article does not have an abstract.
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In this paper, we attempted to construct a constitutive model to deal with the phenomenon of cavitation and cavity growth in a rubber-like material subjected to an arbitrary tri-axial loading. To this end, we considered a spherical elementary representative volume in a general Rivlin's incompressible material containing a central spherical cavity. The kinematics proposed by [Hou, H.S., Abeyaratne, R., 1992. Cavitation in elastic and elastic-plastic solids. J. Mech. Phys. Solids 40, 571-722] was adopted in order to construct an approximate but optimal field. In order to establish a suitable constitutive law for this class of materials, we utilized the homogenisation technique that permits us to calculate the average strain energy density of the volume. The cavity growth was considered through a physically realistic failure criterion. Combination of the constitutive law and the failure criterion enables us to describe correctly the global behaviour and the damage evolution of the material under tri-axial loading. It was shown that the present models can efficiently reproduce different stress states, varying from uniaxial to tri-axial tensions, observed in experimentations. Comparison between predicted results and experimental data proves that the proposed model is accurate and physically reasonable. Another advantage is that the proposed model does not need special identification work, the initial Rivlin's law for the corresponding incompressible material is sufficient to form the new law for the compressible material resulted from cavitation procedure. (C) 2007 Elsevier Ltd. All rights reserved.
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Discurso proferido durante a 1ª Sessão da Câmara dos Deputados na nova capital do país. Discorre sobre o problema da falta d'água no seu apartamento de Brasília e ainda solicita providênciar local para funcionamento da Comissão de Valorização Econômica da Amazônia.
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Cover [pdf, 0.2 Mb] The state of PICES Science - 2001 [pp. 1-2] [pdf, 0.2 Mb] Reception remarks at PICES X [pp. 3-4] [pdf, 0.3 Mb] The state of the western North Pacific in the first half of 2001 [pp. 5-7] [pdf, 0.8 Mb] The status of the Bering Sea: January - August 2001 [pp. 8-9] [pdf, 0.4 Mb] The state of the eastern Norht Pacific since spring 2001[pp. 10-11] [pdf, 0.3 Mb] 2001 SEEDS experiment in the western Norht Pacific [pp. 12-13] [pdf, 0.5 Mb] Plans for the Canadian SOLAS Iron Enrichment Experiment [pp. 14-15] [pdf,. 0.4 Mb] Photo highlights of the PICES Tenth Annual Meeting [pp. 16-17] [pdf,. 0.3 Mb] NEAR-GOOS 2001 Ocean Environment Forecasting Workshop [pp. 18-19] [pdf, 0.6 Mb] IRI/IPRC Pacific Climate-Fisheries Workshop [pp. 20-21] [pdf, 0.2 Mb] PICES North Pacific Ecosystem Status Report [p. 21] [pdf,. 0.2 Mb] U.S. GLOBEC Northeast Pacific Ocean Program [pp. 22-26] [pdf, 0.5 Mb] New PICES Committee and Program Chairmen biographies [pp. 27-29] [pdf,. 0.4 Mb] Upcoming PICES publications and meetings [p. 30] [pdf,. 0.2 Mb] North Pacific Transitional Areas Symposium [p. 31] [pdf, 0.5 Mb] Gijon Symposium and other PICES announcements [p. 32] [pdf, 0.4 Mb]
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The state of PICES science – 2000 [pp. 1-2] [pdf, 0.6 Mb] The state of the western North Pacific in the first half of 2000 [pp. 3-5] [pdf, 0.7 Mb] The status of the Bering Sea: January – August 2000 [pp. 6-7] [pdf, 0.3 Mb] The state of the eastern North Pacific since spring 2000 [pp. 8-9] [pdf, 0.4 Mb] Makoto Kashiwai [pp. 10-14] [pdf, 0.9 Mb] Alkalinity measurement quality improves for PICES nations [pp. 15-16] [pdf, 0.4 Mb] Dr. Timothy R. Parsons Awarded 2001 Japan Prize [p. 17] [pdf, 0.2 Mb] Highlights of the PICES Nineth Annual Meeting [pp. 18-19] [pdf, 0.4 Mb] Tangible outline of the whole elephant (Results of ecosystem studies of biological resources in the far-eastern seas in 1990s) [pp. 20-24] [pdf, 0.7 Mb] The Oshoro Maru: A short history of Hokkaido University's workhorse in the North Pacific [pp. 25-28] [pdf, 0.4 Mb] Bering Sea and North Pacific Ocean Theme Page [pp. 29-30] [pdf, 0.3 Mb] PICES IX Japan/East Sea cruise [pp. 31-34] [pdf, 1.1 Mb] 35 PICES Wooster Award [p. 35] [pdf, 0.2 Mb] PICES Intern Program [p. 35] [pdf, 0.2 Mb] Obituary - Prof. Michael M. Mulin [p. 36] [pdf, 0.2 Mb]
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19 p.
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Presentado en el III Workshop F.E.R.C.A.N (Fontes Epigraphici Religionum Celticarum Aantiquarum)
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针对实时图形绘制中关键的隐藏面消除算法的效率问题 ,分析了实时视觉仿真中帧连贯性现象 ,提出了利用帧连贯性改进的深度排序算法。在低端平台上实现了实时视觉仿真 ,比较了简单排序算法和改进排序算法的性能 ,并对不同的视点运动算法执行的效果进行了分析。
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Kolokioaren agiriak : XVIII.mendea Euskal Herrian letretan eta historian: Baionan 2004ko azaroaren 18 eta 19an, Bonnat museoan / Actes du Colloque:Le XVIIIe siècle au Pays Basque à travers les lettres et l'histoire, Musée Bonnat, Bayonne, 18-19 novembre 2004.