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Found 6273 publications

Correlation between the mechanical and the geometrical state of railway vehicle carriages

Lajos Borbás László Bozóky Vince Nagy

Publication Name: Proceedings of the Mini Conference on Vehicle System Dynamics Identification and Anomalies

Publication Date: 2002-12-01

Volume: Unknown

Issue: Unknown

Page Range: 261-269

Description:

The railway vehicle's carriage body must be mechanically repaired if cracks appear in its structure. In such cases all factors concerning the mechanical state of the carriage body should be examined, such as connection between the carriages, adjustment of the wheel forces, the different running states and running on straight and curved track. The aim of this study is to provide the mechanical stress values summarising the simultaneous effects of all these factors.

Open Access: Yes

DOI: DOI not available

A numerical C1-shadowing result for retarded functional differential equations

Gyula Farkas

Publication Name: Journal of Computational and Applied Mathematics

Publication Date: 2002-08-15

Volume: 145

Issue: 2

Page Range: 269-289

Description:

The aim of the present paper is to give a numerical C1-shadowing between the exact solutions of a functional differential equation and its numerical approximations. The shadowing result is obtained by comparing exact solutions with numerical approximation which do not share the same initial value. Behavior of stable manifolds of functional differential equations under numerics will follow from the shadowing result. © 2001 Elsevier Science B.V. All rights reserved.

Open Access: Yes

DOI: 10.1016/S0377-0427(01)00581-7

Construction of two-sided bounds for initial-boundary value problems

C. Grossmann Zoltán Horváth

Publication Name: Applied Numerical Mathematics

Publication Date: 2002-08-01

Volume: 42

Issue: 1-3

Page Range: 177-187

Description:

The present paper extends the bounding operator approach developed for boundary value problems to the case of initial-boundary value problems (IBVPs). Following the general principle of bounding operators enclosing methods for the case of partial differential equations are discussed. In particular, continuous discretization methods with an appropriate error bound controlled shift and monotone extensions of Rothe's method for parabolic problems are investigated. © 2001 IMACS. Published by Elsevier Science B.V. All rights reserved.

Open Access: Yes

DOI: 10.1016/S0168-9274(01)00149-0

An update on recurrent acute pancreatitis: Data from five European countries

Gyula Farkas Hans Beger Paul Lankisch Philippe Levy Raffaele Pezzilli Lucio Gullo Constantine Arvanitakis Marina Migliori Attila Oláh

Publication Name: American Journal of Gastroenterology

Publication Date: 2002-08-01

Volume: 97

Issue: 8

Page Range: 1959-1962

Description:

OBJECTIVE: A great number of studies have been published on acute pancreatitis, but few have focused on the recurrent form. In this study, we have sought to determine the relative frequency and mortality of recurrent acute pancreatitis, and also to update our knowledge of its etiological factors. METHODS: Patients were selected from a total of 1068 persons included in a previous European study of acute pancreatitis. All were admitted to a hospital with an attack of acute pancreatitis between January, 1990 and December, 1994. Data for each patient was recorded on a standardized form. RESULTS: Of the 1068 with acute pancreatitis, 288 (27%) had recurrent pancreatitis; the majority (78.8%) were men, with a mean age of 43 yr (range 16-95 yr). Regarding etiology, alcohol was the most frequent factor (57%), followed by gallstones (25%), other factors (7.6%), and no identified factor (10.4%). Of the 288 patients, 17 (5.9%) died, all of whom had necrotizing pancreatitis; among all of the patients with necrotizing pancreatitis (141 of 288), the mortality was 12.1%. These percentages are lower than those for patients who had a single attack (8.5% and 18.6%, respectively), but not to a statistically significant degree. Mortality was significantly lower among patients with alcoholic pancreatitis (6.9%) than among those with biliary (30%) (p < 0.002) or idiopathic pancreatitis (25%) (p < 0.04). Most of the deaths (82.4%) occurred at the second attack of pancreatitis. CONCLUSION: Acute recurrent pancreatitis remains a frequent disease, with alcohol being the most frequent etiological factor. Mortality is similar to that of a single episode of acute pancreatitis, and it is significantly lower among patients with alcohol as the etiology. © 2002 by Am. Coll. of Gastroenterology.

Open Access: Yes

DOI: 10.1016/S0002-9270(02)04264-8

Nonexistence of uniform exponential dichotomies for delay equations

Gyula Farkas

Publication Name: Journal of Differential Equations

Publication Date: 2002-06-10

Volume: 182

Issue: 1

Page Range: 266-268

Description:

No description provided

Open Access: Yes

DOI: 10.1006/jdeq.2001.4156

An open architecture patient monitoring system using standard technologies

B. Benyo Z. Benyó Péter Várady

Publication Name: IEEE Transactions on Information Technology in Biomedicine

Publication Date: 2002-03-01

Volume: 6

Issue: 1

Page Range: 95-98

Description:

Computer-aided bedside patient monitoring is applied in areas where real-time vital function analysis takes place. Modern bedside monitoring requires not only the networking of bedside monitors with a central monitor but also other standard communication interfaces. In this paper, a novel approach to patient monitoring is introduced. A patient monitoring system was developed and implemented based on an existing industry standard communication network, using standard hardware components and software technologies. The open architecture system design offers scalability, standard interfaces, and flexible signal interpretation possibilities.

Open Access: Yes

DOI: 10.1109/4233.992168

Algorithm for D-V cells and fundamental domains, E4 space groups with broken translations in the icosahedral family

No authors available

Publication Name: Journal for Geometry and Graphics

Publication Date: 2002-01-01

Volume: 6

Issue: 1

Page Range: 1-16

Description:

As a continuation of our earlier work [2] we extend our algorithm for E4-space groups in the icosahedral family, where non-lattice translations (broken translations) occur as well. So we obtain new 4-polytopes as fundamental domains from D-V cells of crystallographic orbits. We illustrate our situations by some characteristic examples. A computer program will produce further results.

Open Access: No

DOI: DOI not available

Quantitative determination of protein of bacterial origin on the basis of D-aspartic acid and D-glutamic acid content

G. Pohn J. Schmidt É Csokona É Varga-Visi Zs Csapó-Kiss J. Csapó

Publication Name: Chromatographia

Publication Date: 2002-01-01

Volume: 56

Issue: SUPPL.

Page Range: S169-S171

Description:

In recent decades several methods have been developed for determination of the proportion of nitrogen-containing substances passed from the rumen into the abomasum, or small intestine, which are of microbial origin. Recently, when examining the D-amino acid content of foodstuffs, particularly milk and milk products, it was observed that, in addition to D-alanine (D-Ala), D-glutamic acid (D-Glu) and D-aspartic acid (D-Asp) can also be detected in similar quantities, primarily in products which have links with bacterial activity. This gave rise to the idea of examining the diaminopimelic acid (DAPA), D-Glu, and D-Asp content of bacteria extracted from the rumen of cattle, and that of chyme from the same cattle, to establish whether D-Asp and D-Glu can be used to estimate protein of bacterial origin. The investigations performed have provided evidence that both D-Asp and D-Glu might be appropriate for determination of protein of bacterial origin. The results obtained using these two bacterial markers (D-Asp and D-Glu) proved to be approximately 10% lower than those obtained using DAPA; this was not because of to error attributable to the new markers but rather to the unreliability of determination using DAPA Analyses performed on samples of known bacterial protein content indicate that D-Asp and D-Glu gave almost identical results for bacterial protein content which were very close to the theoretical (calculated) values.

Open Access: Yes

DOI: 10.1007/bf02494132

Effect of subsoiling on the yield of sugar beet under conditions of rhizomania infection.

No authors available

Publication Name: Mededelingen (Rijksuniversiteit te Gent. Fakulteit van de Landbouwkundige en Toegepaste Biologische Wetenschappen)

Publication Date: 2002-01-01

Volume: 67

Issue: 2

Page Range: 321-325

Description:

The rhizomania is known in Hungary since 1982. The causal agent, Beet necrotic yellow vein benyvirus (BNYVV) is transmitted by a soil-borne fungus Polymyxa betae Keskin. A field experiment was done under rhizomania infested and non-infested conditions to compare the yield parameters of five tolerant and four sensitive sugar beet hybrids. Tolerant varieties produced higher root yield under rhizomania infected conditions. The root yields of the sensitive varieties were similar to the tolerant ones on the uninfested field, but the root mass of some tolerant varieties exceeded the production of the former group. Subsoiling was carried out in two strips of a heavily infested field, while conventional soil cultivation was done on the other parts. There was not any other difference in the cultivation of the treated and control areas. Sugar beet root samples were collected at the time of harvesting from the subsoiled and control plots. Beet necrotic yellow vein virus (BNYVV) infection was tested by means of ELISA. Virus content, yield and yield parameters of samples were compared. There were no significant differences in virus infection between sugar beet roots derived from subsoiled and untreated plots. Ratio of BNYVV infected plants was about 90% in both areas. However, yield and yield parameters showed remarkable difference. Root yield of treated plots, calculated from average individual root weight and 80,000 plant/ha plant density exceeded by 140% the yield of control. Sugar content was 2.6% higher and the harmful non-sugar content was lower on the subsoiled plots. Owing to the favourable chemical and technological value of beet the white sugar content was approximately three-times higher on the treated area.

Open Access: No

DOI: DOI not available