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51.
Ofer Arieli Marc Denecker Bert Van Nuffelen Maurice Bruynooghe 《Annals of Mathematics and Artificial Intelligence》2006,46(1-2):4-37
We introduce a simple and practical method for repairing inconsistent databases. Given a possibly inconsistent database, the idea is to properly represent the underlying problem, i.e., to describe the possible ways of restoring its consistency. We do so by what we call signed formulae, and show how the ‘signed theory’ that is obtained can be used by a variety of off-the-shelf computational models in order
to compute the corresponding solutions, i.e., consistent repairs of the database.
*This paper is a revised and extended version of [9]. 相似文献
52.
R. Lyonnet A. Khodan A. Barthe´le´my J.-P. Contour O. Durand J.L. Maurice D. Michel J. Teresa de 《Journal of Electroceramics》2000,4(2-3):369-377
We have studied the pulsed laser deposition (PLD) of Zr1-xCexO2 and Ce1-xLaxO2-x/2 initially to grow buffer layers for perovskite films deposited on Si, LaAlO3, SrTiO3 and MgO and then to produce tunneling barriers for cuprate or manganite heterostructures. On (1 0 0) Si, the deposition of Zr1-xCexO2 (x = 0.12) produces a smooth epitaxial layer (R
RMS = 0.25/1m2), which allows the further deposition of high quality YBa2Cu3O7 (Tc 88 K) and La0.7Sr0.3MnO3 films. On the other hand, the use of Ce1-xLaxO2-x/2 (0 x 0.4) makes it possible to match the YBa2Cu3O7 and La0.7Sr0.3MnO3 layers to various substrates. The buffer layers are epitaxially grown with a 45° rotation of the in-plane axes with respect to those of the substrate, and the smoothness is high (R
RMS = 0.25/1m2). In the case of an ultra-thin barrier (2.5 nm) of Ce1-xLaxO2-x/2 sandwiched in a La0.7Sr0.3MnO3, the out-of-plane mismatch of 2 induces distortions at the interface steps, which propagate into the topmost La0.7Sr0.3MnO3 layer. This is in contrast to the case of SrTiO3 barriers where an ideal crystal continuity in the growth direction is observed. 相似文献
53.
We introduce a linear systolic array for the Longest Common Subsequence (LCS, for short) problem. We first present an array of m identical cells which computes the length of an LCS of two strings of length m and n, respectively, in linear time (i.e., in time proportional to m + n). Then we show that, by extending any cell with the systolic stack introduced by Guibas and Liang (1982), a new array can be designed to recover an LCS in linear time. 相似文献
54.
55.
Pulmonary tuberculosis: primary tuberculosis, usually asymptomatic, represents the first infection and is shown by a parenchymal mostly mid-pulmonary focus and satellite lymphadenopathy. Postprimary pulmonary tuberculosis, mostly located in the upper fields may be caused by endogenous reinfection for reactivation of a hematogenous focus formed during primary infection or from exogenous reinfection. Extrapulmonary tuberculosis: it includes numerous forms mostly from hematogenous spread. Miliary tuberculosis may involve a number of organs and apparatus besides the lung. Tuberculous meningitis predominantly involves the base of the skull, the fluid is clear with hypoglycorrhachia and lymphocyte pleocytosis. Lymph node tuberculosis is generally unilateral and cervical. Tuberculous pleuritis is exudative or dry. Other forms of tuberculous serositis are pericarditis and peritonitis. Renal tuberculosis involves the medullaris and intestinal tuberculosis the ileocecum; tuberculous spondilitis (Pott's disease) involves the last dorsal vertebrae. Other forms are osteoarthritis, genital tract tuberculosis, pancreatitis, laryngitis, otitis. 相似文献
56.
P Sellier B Eisenmann P Charon JL Guermonprez P Maurice 《Canadian Metallurgical Quarterly》1976,15(3):477-480
In this study, the effects of forearm static exercise were determined on local blood flow and oxygen consumption in 15 normal individuals (NL) and their responses were compared with ten patients in congestive heart failure (CHF). Forearm blood flow was determined by a plethysmographic technique before and during 15% of maximum voluntary contraction of the forearm. Regional arterial and venous oxygen contents were sampled and forearm oxygen consumption calculated by the Fick principle. At rest, forearm blood flow was less in patients with heart failure than in normal individuals; however, this was compensated for by an increased oxygen extraction, thus maintaining forearm oxygen consumption at a normal level. In contrast, during static exercise, forearm blood flow failed to rise normally with heart failure (NL 9.31; CHF 4.35 ml/min-100 ml, P less than 0.001) and the increased oxygen extraction was not sufficient to maintain a normal forearm oxygen consumption (NL .82; CHF .44 ml/min-100 ml, P less than 0.01). Therefore, patients with congestive heart failure demonstrate regional circulatory and metabolic abnormalities during static exercise that are comparable to those present during dynamic exercise. Because of a limited ability of their skeletal muscle resistance vessels to respond to dilator stimuli, they have an attenuation of their exercise hyperemia which leads to an earlier shift to anaerobic metabolism. 相似文献
57.
Oxide layers grown on the surface provide an effective way of protecting metallic materials against corrosion for sustainable use in a broad range of applications. However, the growth of cavities at the metal/oxide interface weakens the adherence of the protective layer and can promote its spallation under service conditions, as observed for alumina layers formed by selective oxidation of aluminide intermetallic alloys used in high-temperature applications. Here we show that direct atomic-scale observations of the interface between an ultrathin protective oxide layer (alumina) grown on an intermetallic titanium aluminide substrate (TiAl) can be performed with techniques sensitive to the topmost atomic layers at the surface. Nanocavities resulting from the self-assembling of atomic vacancies injected at the interface by the growth mechanism of the protective oxide are observed for the first time, bringing new insight into the understanding of the fate of injected cavities in oxidation processes. 相似文献
58.
A read-modify-write register for a set of functions F provides an operation that atomically (1) returns the variables current value v, and (2) replaces that value with f(v), where f is a function in F.A read-modify-write network is a distributed data structure that implements a concurrent, lock-free, low-contention read-modify-write register. For example, counting networks ([3]) are a family of read-modify-write networks that support atomic increments and decrements.We consider the problem of constructing read-modify-write networks for particular sets of functions. Of particular interest are the read-modify-write networks fetch&add, which add to the value an arbitrary number, and fetch&mul, which multiply the value by an arbitrary number.We identify a simple algebraic property of the function set F that requires any distributed read-modify-write implementation for F to have high latency. Any such network has sequential executions in which each token traverses a number of switching elements essentially linear in the number of processes. By contrast, there exist counting networks ([9, 18]) in which tokens traverse a logarithmic number of switches.We provide a matching upper bound for a large class of read-modify-write networks including fetch&add, fetch&mul, and related networks of interest.Received: 15 October 2002, Accepted: 15 May 2003, Published online: 6 February 2004Panagiota Fatourou: Partially supported by funds from the Program E.
.E.A.E.K.II of the Greek Ministry of Education. Part of the work of theauthor was performed while at the Max-Planck Institut für Informatik,Saarbrücken, Germany, while at the Department of Computer Science,University of Toronto, Canada, and while visiting the Departmentof Computer Science, Brown University, Providence, USA.Maurice Herlihy: Partially supported by NSF grant 9912401.A preliminary version of this work appears in the Proceedings of the 15th International Symposium on DIStributed Computing, pp. 330-341, Lisbon, Portugal, October 2001. This work also appears as a brief announcement in the Proceedings of the 20th Annual ACM Symposium on Principles of Distributed Computing, Newport, Rhode Island, August 2001. 相似文献
59.
"A sample of 423 psychotic patients from five veterans hospitals was observed and rated on behavior in the interview and on the ward. The intercorrelations between 55 of the rating scales were subjected to a multiple group factor analysis. The 11 oblique first order factors were interpreted." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Larry J. Darlage Harry N. Finkbone Samuel J. King Jitendra Ghosal Maurice E. Bailey 《Fuel》1978,57(8):479-484
A series of 34 nitrogen-containing compounds with a wide range of basicities was examined under differential nonaqueous potentiometric conditions in acetophenone and nitrobenzene. These compounds could be resolved into five classes based on pKaand half-neutralization-potential (HNP) values. Asphaltenes isolated from the vacuum still overhead (VSO) and vacuum still bottoms (VSB) fractions of the H-coal process were titrated under similar conditions. The titration results of both asphaltenes indicated the presence of two classes of nitrogen-containing compounds, a titratable class of the pyridine-ring or aniline type and a nontitratable class. 相似文献