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Fundamental Level (fundamental + level)
Selected AbstractsPHYSICALISM, SUPERVENIENCE AND THE FUNDAMENTAL LEVELTHE PHILOSOPHICAL QUARTERLY, Issue 234 2009Robin Brown We provide a formulation of physicalism, and show that this is to be favoured over alternative formulations. Much of the literature on physicalism assumes without argument that there is a fundamental level to reality, and we show that a consideration of the levels problem and its implications for physicalism tells in favour of the form of physicalism proposed here. Its key elements are, first, that the empirical and substantive part of physicalism amounts to a prediction that physics will not posit new entities solely for the purpose of accounting for mental phenomena, nor new entities with essentially mental characteristics such as propositional attitudes or intentions; secondly, that physicalism can safely make do with no more than a weak global formulation of supervenience. [source] Ontological Priority, Fundamentality and MonismDIALECTICA, Issue 3 2009Winner of the 2008 dialectica essay prize In recent work, the interrelated questions of whether there is a fundamental level to reality, whether ontological dependence must have an ultimate ground, and whether the monist thesis should be endorsed that the whole universe is ontologically prior to its parts have been explored with renewed interest. Jonathan Schaffer has provided arguments in favour of ,priority monism' in a series of articles (2003, 2004, 2007a, 2007b, forthcoming). In this paper, these arguments are analysed, and it is claimed that they are not compelling: in particular, the possibility that there is no ultimate level of basic entities that compose everything else is on a par with the possibility of infinite ,upward' complexity. The idea that we must, at any rate, postulate an ontologically fundamental level for methodological reasons (Cameron 2008) is also discussed and found unconvincing: all things considered, there may be good reasons for endorsing ,metaphysical infinitism'. In any event, a higher degree of caution in formulating metaphysical claims than found in the extant literature appears advisable. [source] On accuracy of the finite-difference and finite-element schemes with respect to P -wave to S -wave speed ratioGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2010Peter Moczo SUMMARY Numerical modelling of seismic motion in sedimentary basins often has to account for P -wave to S -wave speed ratios as large as five and even larger, mainly in sediments below groundwater level. Therefore, we analyse seven schemes for their behaviour with a varying P -wave to S -wave speed ratio. Four finite-difference (FD) schemes include (1) displacement conventional-grid, (2) displacement-stress partly-staggered-grid, (3) displacement-stress staggered-grid and (4) velocity,stress staggered-grid schemes. Three displacement finite-element schemes differ in integration: (1) Lobatto four-point, (2) Gauss four-point and (3) Gauss one-point. To compare schemes at the most fundamental level, and identify basic aspects responsible for their behaviours with the varying speed ratio, we analyse 2-D second-order schemes assuming an elastic homogeneous isotropic medium and a uniform grid. We compare structures of the schemes and applied FD approximations. We define (full) local errors in amplitude and polarization in one time step, and normalize them for a unit time. We present results of extensive numerical calculations for wide ranges of values of the speed ratio and a spatial sampling ratio, and the entire range of directions of propagation with respect to the spatial grid. The application of some schemes to real sedimentary basins in general requires considerably finer spatial sampling than usually applied. Consistency in approximating first spatial derivatives appears to be the key factor for the behaviour of a scheme with respect to the P -wave to S -wave speed ratio. [source] Theoretical analysis of the effects of asymmetric membrane structure on fouling during microfiltrationAICHE JOURNAL, Issue 6 2009Weiyi Li Abstract There is a growing interest in the use of both asymmetric and composite membranes for microfiltration and ultrafiltration processes. This includes particle removal applications in the semiconductor industry and virus clearance in biopharmaceutical applications. Filter fouling plays an important role in these processes. Although flux decline models have been developed for homogeneous membranes, the effects of asymmetric membrane structure on flux decline behavior remain poorly understood on a fundamental level. Here, we develop a theoretical model to describe the effects of asymmetric membrane structure on flux decline. The asymmetric structure was described by the spatial variation in Darcy permeability in the directions normal to and parallel to the membrane surface. The velocity profile and flux decline because of pore blockage were described using Darcy's law and a pore blockage and cake filtration model. Flux decline data were obtained using pseudocomposite membranes with highly interconnected polyvinylidene fluoride membranes (PVDF) and straight through pore polycarbonate track-etched membranes (PCTE). Model composite membranes were formed by layering PCTE or PVDF membranes with different pore sizes on top of each other. Flux decline data for the composite membrane were in good agreement with model calculations. The results provide important insights into the effects of asymmetric membrane pore structures on flux decline. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Vacuum drying of wood with radiative heating: II.AICHE JOURNAL, Issue 1 2004Comparison between theory, experiment Abstract In part I of this work extensive experimental data sets for the vacuum drying of wood with radiative heating were presented for sapwood and heartwood of different species (Picea abies, Abies alba, and Fagus silvatica). These data sets are used here to validate two previously developed drying models. The first drying model, which is known as TransPore, is a comprehensive model able to capture the intricately coupled heat- and mass-transfer mechanisms that evolve throughout the drying process. The second model, which is known as Front_2D, uses a number of simplifying assumptions to reduce the complexity of the comprehensive model to a system that enables a semianalytical approach to be exploited for its solution. Although the first model provides a more accurate description of the entire process, the second model is able to produce representative solutions very efficiently in terms of overall computational times, making it a viable option for on-line control purposes. The comparison with experimental data highlights that both models are able to capture all of the observed trends, allowing them to be used with confidence for investigating the vacuum drying process at a fundamental level. The new contribution of this work lies in the fact that both models are used here for the first time to simulate drying at a reduced external pressure. © 2004 American Institute of Chemical Engineers AIChE J, 50: 108,118, 2004 [source] PHYSICALISM, SUPERVENIENCE AND THE FUNDAMENTAL LEVELTHE PHILOSOPHICAL QUARTERLY, Issue 234 2009Robin Brown We provide a formulation of physicalism, and show that this is to be favoured over alternative formulations. Much of the literature on physicalism assumes without argument that there is a fundamental level to reality, and we show that a consideration of the levels problem and its implications for physicalism tells in favour of the form of physicalism proposed here. Its key elements are, first, that the empirical and substantive part of physicalism amounts to a prediction that physics will not posit new entities solely for the purpose of accounting for mental phenomena, nor new entities with essentially mental characteristics such as propositional attitudes or intentions; secondly, that physicalism can safely make do with no more than a weak global formulation of supervenience. [source] The Treasury of Metaphysics and the Physical WorldTHE PHILOSOPHICAL QUARTERLY, Issue 216 2004Charles Goodman Most modern analytic philosophers have ignored works of Indian philosophy such as Vasubandhu's ,Treasury of Metaphysics'. This neglect is unjustified. The account of the nature of the physical world given in the ,Treasury' is a one-category ontology of dharmas, which are simple, momentary tropes. They include bade physical tropes, the most fundamental level of the physical world, as well as higher-level tropes, including sensible properties such as colours, which are known as derived form. I argue that the relationship between the basic physical tropes and derived form is one of supervenience. Vasubandhu's theory is a powerful and flexible one, which can be adapted so as to be consistent with modern science. [source] Provisioning in complex networksBELL LABS TECHNICAL JOURNAL, Issue 1 2007Ganesan Radhakrishnan IP Multimedia Subsystem (IMS) solutions emphasize services including all-Internet Protocol (IP) voice, data, video, multimedia, and other user-centric services. IMS applications allow network convergence among wireline, wireless, and packet networks and interaction of services in disparate, multivendor, multitechnology networks. This increased level of sophistication leads to increased operational complexity and underscores the need for a unified provisioning system to minimize the overhead of managing network data. This paper outlines a scalable, distributed, provisioning framework for disparate data networks. It examines the current approaches to provisioning and their shortcomings in dealing with disparate data. At a fundamental level, it views provisioning as two distinct problems of data management and process modeling. It depicts a unifying framework, by separating data management from the application that provisions the data, leading to data-model independence. It shows that unified provisioning requires the support of many distinct technologies including federated data management, software component framework, distributed computing framework, and formalisms for describing behavior. © 2007 Alcatel-Lucent. [source] Adhesion of pancreatic beta cells to biopolymer filmsBIOPOLYMERS, Issue 8 2009S. Janette Williams Abstract Dramatic reversal of Type 1 diabetes in patients receiving pancreatic islet transplants continues to prompt vigorous research concerning the basic mechanisms underlying patient turnaround. At the most fundamental level, transplanted islets must maintain viability and function in vitro and in vivo and should be protected from host immune rejection. Our previous reports showed enhancement of islet viability and insulin secretion per tissue mass for small islets (<125 ,m) as compared with large islets (>125 ,m), thus, demonstrating the effect of enhancing the mass transport of islets (i.e. increasing tissue surface area to volume ratio). Here, we report the facile dispersion of rat islets into individual cells that are layered onto the surface of a biopolymer film towards the ultimate goal of improving mass transport in islet tissue. The tightly packed structure of intact islets was disrupted by incubating in calcium-free media resulting in fragmented islets, which were further dispersed into individual or small groups of cells by using a low concentration of papain. The dispersed cells were screened for adhesion to a range of biopolymers and the nature of cell adhesion was characterized for selected groups by quantifying adherent cells, measuring the surface area coverage of the cells, and immunolabeling cells for adhesion proteins interacting with selected biopolymers. Finally, beta cells in suspension were centrifuged to form controlled numbers of cell layers on films for future work determining the mass transport limitations in the adhered tissue constructs. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 676,685, 2009. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] | |||||||||||||