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Objective Way (objective + way)
Selected AbstractsError estimation in a stochastic finite element method in electrokineticsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 11 2010S. Clénet Abstract Input data to a numerical model are not necessarily well known. Uncertainties may exist both in material properties and in the geometry of the device. They can be due, for instance, to ageing or imperfections in the manufacturing process. Input data can be modelled as random variables leading to a stochastic model. In electromagnetism, this leads to solution of a stochastic partial differential equation system. The solution can be approximated by a linear combination of basis functions rising from the tensorial product of the basis functions used to discretize the space (nodal shape function for example) and basis functions used to discretize the random dimension (a polynomial chaos expansion for example). Some methods (SSFEM, collocation) have been proposed in the literature to calculate such approximation. The issue is then how to compare the different approaches in an objective way. One solution is to use an appropriate a posteriori numerical error estimator. In this paper, we present an error estimator based on the constitutive relation error in electrokinetics, which allows the calculation of the distance between an average solution and the unknown exact solution. The method of calculation of the error is detailed in this paper from two solutions that satisfy the two equilibrium equations. In an example, we compare two different approximations (Legendre and Hermite polynomial chaos expansions) for the random dimension using the proposed error estimator. In addition, we show how to choose the appropriate order for the polynomial chaos expansion for the proposed error estimator. Copyright © 2009 John Wiley & Sons, Ltd. [source] Commentary: Accounting Schism or Synthesis?ACCOUNTING PERSPECTIVES, Issue 2 2002A Challenge for the Conditional-Normative Approach ABSTRACT This paper explains the conditional-normative accounting methodology (CoNAM) and its origin, offering a comparison of the normative, positive, and conditional-normative approaches. It also discusses the difference between the pragmatic versus a more scientific treatment of CoNAM. However, the main thrust of the paper is directed toward the schism in academic accounting between the positive accounting theory (PAT) and the critical interpretive view (CIV). To better understand CIV, the paper attempts to explain the philosophic roots that reach from Husserl and some Marxist writers to Foucault, Derrida, and Baudrillard. This schism seems to call for a new synthesis that avoids extreme positions but draws upon insights from both camps. In this search, CoNAM might be helpful by exploring means-end relations and connecting value judgements to accounting theory in a fairly "objective" way. [source] Quantifying tibial plafond fracture severity: Absorbed energy and fragment displacement agree with clinical rank orderingJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2008Donald D. Anderson Abstract The energy of producing a fracture is considered one of the most important factors relating to injury severity, prognosis, and risk of complications, yet there has been no objective way to measure this important variable. The purpose of this study was to compare assessments of fracture severity made using new objective computed tomography (CT),based methods versus the expert opinion of experienced orthopedic traumatologists. Fracture energy, fragment displacement, and soft tissue swelling were quantified in twenty tibial plafond fractures by analyzing injury CT scans. Three experienced orthopedic traumatologists then independently performed a rank order analysis of fracture severity, using plain radiographs. The concordance among the three clinicians ranged from 87% to 91%. Objective fracture severity measurements made with the CT algorithm agreed well with the clinical assessments (fracture energy concordance from 73% to 76%, fragment displacement from 82% to 89%, and soft tissue swelling from 61% to 65%). These are the first objective, CT-based measures of fracture severity. With further refinement, this conceptually novel method has the potential to serve as a valuable tool to provide objective measurement of fracture severity, allowing one to control for this previously confounding variable in large multicenter studies. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1046,1052, 2008 [source] Computerised morphometric study of the paraurethral tissue in young and elderly womenNEUROUROLOGY AND URODYNAMICS, Issue 6 2002M. Verelst Abstract Aim. Changes in structural support of the urethra and bladder neck have been proposed to be among the most important factors in the pathogenesis of stress urinary incontinence. In this context, we histologically investigated the paraurethral area in continent women to quantify the relative distribution of connective tissue, smooth muscle, vessels, nerves, and striated muscle. Previously published literature gives only descriptive evaluations of the relative distribution of these tissue components. Methods. We used a computerised morphometric method, which allowed us to estimate the paraurethral tissue distribution in a more objective way. The material was obtained by dissection during autopsy in five premenopausal and five postmenopausal women. Results. Paraurethral tissue consisted of 56% connective tissue (SD, 5%), 30% smooth muscle (SD, 5%), 11% blood vessel (SD, 6%), 2% striated muscle (SD, 3%), and 1% nerves (SD, 1%). We also found that the distribution of different tissue components along the length of the urethra did not differ at a statistically significant level. Furthermore, there was a statistically significant difference in the amount of connective tissue and blood vessels in the postmenopausal women compared with the premenopausal women. Conclusions. The present study shows that the paraurethral area is built of heterogeneous tissue with small changes in its composition along the course of urethra. Increase in connective tissue was found to be the dominating change in the process of ageing. Neurourol. Urodynam. 21:529,533, 2002. © 2002 Wiley-Liss, Inc. [source] Technical note: A new three-dimensional technique for high resolution quantitative recording of perikymataAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010E. Bocaege Abstract The number and spacing of incremental markings at the enamel surface, known as perikymata, are considered important indicators of dental growth patterns, as they provide information on crown formation times and the underlying developmental processes. This study explores the potential of a new three-dimensional technique for the reconstruction of dental growth profiles, using teeth from a medieval child from Abingdon, Oxfordshire. The crowns of three anterior teeth were imaged and analyzed using the Alicona 3D InfiniteFocus imaging microscope. Individual perikyma grooves can be unambiguously identified on a profile of the reconstructed enamel surface and direct distances between successive pairs of perikyma grooves can be calculated from coordinate data. This quantitative approach constitutes a more objective way to record perikymata spacing than current methods. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source] Cluster analyses of metal-organic fragments using the dSNAP softwareACTA CRYSTALLOGRAPHICA SECTION B, Issue 6 2009Anna Collins The dSNAP computer program has been used to classify searches of the Cambridge Structural Database for two ligands: ,O,CH2,CH2,O, and N(CH2CH2O,)3 commonly found in metal-organic systems. The clustering method used is based on total geometries (i.e. all the lengths and angles involving all the atoms in the search fragment, whether bonded or not) and proved capable of distinguishing in a wholly automatic, objective way between different types of metal complex purely on the basis of the geometry of the ligand and the relative positions of the O atoms to the metals. [source] A Study of Industry Evolution in the Face of Major Environmental Disturbances: Group and Firm Strategic Behaviour of Spanish Banks, 1983,1997,BRITISH JOURNAL OF MANAGEMENT, Issue 3 2004JoséÁngel Zúñiga-Vicente This paper examines the story of the evolution of a specific industry through the application of dynamic strategic group analysis. In particular, we analyse the relationship between major environmental disturbances and changes that have occurred over time in the competitive structure of the industry regarding two closely related central questions. First, the way in which these environmental transformations have influenced group patterns and stability, and second, the way in which such environmental disturbances has affected the strategic positioning of individual firms. We resort to alternative theoretical perspectives in an attempt to answer both questions. The empirical setting is the population of Spanish banks over the period 1983,1997. We make use of a new grouping algorithm , the Model-based Clustering or MCLUST , which may be enormously fruitful in future empirical works on strategic groups. This method allows researchers to obtain the optimal number of groupings over time in a much more objective way than the cluster techniques used until now. Compared to previous dynamic studies that only consider the largest firms, our research illustrates how a richer analysis of an industry dynamics can be obtained by using a dynamic analysis of strategic groups. Our results show that while there have been no industry-wide identical groupings year to year, there is an important strategic stability at group and firm-level punctuated by a high degree of strategic instability at times of major environmental disturbances. [source] Chromatic sensitivity in subjects with diabetesACTA OPHTHALMOLOGICA, Issue 2009M O'NEILL-BIBA Purpose Diabetic retinopathy is a major cause of blindness in the Western World and remains one of the most serious complications of diabetes mellitus. The gold standard to measure functional change in diabetic (DB) patients is LogMAR or Snellen VA. The aim of this study was to measure and characterise the severity of visual function loss in subjects with DB using sensitive psychophysical tests and to quantify accurately how changes in management of the disease correlate with changes in visual function. Methods Three groups of patients (n=50) were included in this study:DB patients with and without retinopathy and patients with no DB. Each patient had a full ophthalmic examination prior to psychophysical assessment. Colour vision assessment was carried out using the CAD test (Colour Assessment & Diagnosis) that provides a measure of both yellow-blue and red-green loss of chromatic sensitivity (CS). Rapid flicker (RF) was also measured by assessing sensitivity to a 20Hz flicker stimulus at five locations in the central visual field (fovea and 1.5 degrees from fixation in each quadrant). All tests were carried out at photopic and high mesopic light. Results The results show significant loss of CS (p <.001) and some loss in RF sensitivity (p <.01). The most sensitive measure of visual loss was CS. There was also a positive correlation between CAD thresholds as a measure of CS and improved DB control. Conclusion The results suggest that loss of visual function precedes structural changes in the retina and could be used as a means of detecting early structural changes in the retina that precede clinical diagnosis of retinopathy. Preliminary results also suggest that changes in CAD thresholds provide an objective way of monitoring the progress of DB and/or treatment outcome. [source] Comparison of 1- and 2-day protocols for myocardial SPECT: a Monte Carlo studyCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 4 2005H. H. El-Ali Summary Background:, Myocardial perfusion single-photon emission computed tomography (SPECT) is carried out by combining a rest and a stress study that are performed either on one day or two separate days. A problem when performing the two studies on 1 day is that the residual activity from the first study contributes to the activity measured in the second study. Aim:, Our aim was to identify and evaluate trends in the quantification parameters of myocardial perfusion images as a function of separation time between rest and stress. Methods:, A digital phantom was used for the generation of heart images and a Monte Carlo-based scintillation camera program was used to simulate SPECT projection images. In our simulations, the rest images were normal and the stress images included lesions of different types and localization. Two programs for quantification of myocardial perfusion images were used to assess the different images in an automated and objective way. Results:, The summed difference scores observed with the 2-day protocol were 3 ± 1 (mean ± SD) higher for AutoQUANT and 2 ± 1 higher for 4D-MSPECT compared with those observed with the 1-day protocol. The extent values were 2% points higher for the 2-day protocol compared with the 1-day protocol for both programs. Conclusions:, There are differences in the quantitative assessment of perfusion defects depending on the type of protocol used. The contribution of residual activity is larger when a 1-day protocol is used compared with the 2-day protocol. The differences, although small, are of a magnitude that results in a clear shift in quantification parameters. [source] | ||||||||||||||||