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991.
Antonio Campo Cristina H. Amon 《International Journal of Heat and Mass Transfer》2005,48(10):2110-2116
This paper addresses the second Lévêque problem with uniform wall heat flux adhering to the original two-dimensional energy conservation equation with variable coefficients in cylindrical coordinates. The semi-analytic procedure to be proposed combines the transversal method of lines (TMOL) with the Fröbenius version of the power series method. The hybrid solution that emerges from this combination holds unique features that distinguish it from the traditional solution methods. In principle, due to the presence of a two-point backward formulation, the approximate analytic solution is considered first-order accurate. However, using as guidance the computed local convection coefficient at various transversal lines, it is demonstrated that the approximate analytic TMOL/Fröbenius solution is better than first-order accurate. 相似文献
992.
Whitton Sarah W.; Olmos-Gallo P. Antonio; Stanley Scott M.; Prado Lydia M.; Kline Galena H.; St. Peters Michelle; Markman Howard J. 《Canadian Metallurgical Quarterly》2007,21(2):297
The authors proposed a model of depressive symptoms in early marriage in which relationship confidence, defined as perceived couple-level efficacy to manage conflicts and maintain a healthy relationship, mediates the effect of negative marital interactions on depressive symptoms. The model was tested in a sample of 139 couples assessed prior to marriage and 1 year later. As predicted, relationship confidence demonstrated simple negative associations with negative marital interaction and depressive symptoms for all participants. Longitudinal path analyses supported the mediational model for women only. In women but not men, negative marital interaction indirectly had an impact on depressive symptoms through the mediator of relationship confidence. Findings suggest that relationship confidence may be important to understanding links between marital distress and depressive symptoms, especially in women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Pedro Díez Núria Pars Antonio Huerta 《International journal for numerical methods in engineering》2003,56(10):1465-1488
Classical residual type error estimators approximate the error flux around the elements and yield upper bounds of the exact (or reference) error. Lower bounds of the error are also needed in goal oriented adaptivity and for bounds on functional outputs. This work introduces a simple and cheap strategy to recover a lower bound estimate from standard upper bound estimates. This lower bound may also be used to assess the effectivity of the former estimate and to improve it. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
994.
Cristina Urdiales García Antonio Bandera Rubio Fabián Arrebola Pérez Francisco Sandoval Hernández 《Machine Vision and Applications》2003,14(3):145-156
This paper presents a method to segment, characterise and pair a set of chromosomes in a cell of an eukaryotic organism.
This method yields several new features: (i) chromosomes are captured at non-uniform resolution to minimise the problem instance;
(ii) segmentation is adaptively conducted by means of a hierarchical structure in a fast way; (iii) the curvature of each
chromosome is studied at high resolution by means of attentive steps; (iv) a very short and uncorrelated feature vector is
extracted from curvature by analysing its spectral components; and (v) a multistage benchmark classifier is used to pair chromosomes
according to shape and banding. The method has been tested with publicly available databases. Results were successfully compared
to manual karyotypes.
Received: 26 June 2000 / Accepted: 4 December 2001 Published online: 3 June 2003
Correspondence to: Cristina Urdiales García
(e-mail: cris@dte.uma.es, Tel.: +34-952-132757, Fax: +34-952-131447) 相似文献
995.
This paper briefly details the work carried out on the modelling of inductive post filters. This type of filter approach is particularly attractive at millimeter wave frequencies due to its ease of manufacture, however for modelling no true wide band equivalent circuit would seem to be available. In order to overcome this limitation we have developed a rigorous wide band model. The accuracy of the model has been confirmed by numerous experimental measurements and the resulting computer program quickly enables both analysis and synthesis to be carried out. The speed and efficiency of this approach has allowed the effect of mechanical tolerances to be taken into account, thus reducing cost, complexity and assembly times. 相似文献
996.
Javier Ramírez Uwe Meyer-Bäse Fred Taylor Antonio García Antonio Lloris 《The Journal of VLSI Signal Processing》2003,34(3):227-237
The design of high performance, high precision, real-time digital signal processing (DSP) systems, such as those associated with wavelet signal processing, is a challenging problem. This paper reports on the innovative use of the residue number system (RNS) for implementing high-end wavelet filter banks. The disclosed system uses an enhanced index-transformation defined over Galois fields to efficiently support different wavelet filter instantiations without adding any extra cost or additional look-up tables (LUT). A selection of a small wordwidth modulus set are the keys for attaining low-complexity and high-throughput. An exhaustive comparison against existing two's complement (2C) designs for different custom IC technologies was carried out. Results reveal a performance improvement of up to 100% for high-precision RNS-based systems. These structures demonstrated to be well suited for field programmable logic (FPL) assimilation as well as for CBIC (cell-based integrated circuit) technologies. 相似文献
997.
Raquel Ibáñez Marco Peluso Armelle Munnia Sara Piro Carlos A. González Pilar Amiano M. J. Tormo Eva Ardanaz Aurelio Barricarte Antonio Berenguer M. Dolores Chirlaque Miren Dorronsoro Paula Jakszyn Nerea Larrañaga Carmen Martínez Carmen Navarro J. Ramón Quirós M. José Sánchez Antonio Agudo 《European Food Research and Technology》2009,229(4):549-559
The aim of this study was to assess the relationship between bulky DNA adducts in white blood cells (WBC) and lifestyle factors
in a sample from the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC). 296 subjects
aged between 35 and 64 years, from five regions, were included. Food intake was estimated with a computerized version of dietary
history questionnaire. Daily intake of polycyclic aromatic hydrocarbons (PAH) was estimated using a database with information
on food content of potential carcinogens. Data on lifestyle and health factors were collected and DNA adducts measured using
the nuclease P1 32P-postlabelling technique. Geometric means of adducts were similar for men and women (4.11/109 and 3.94/109 nucleotides, respectively). Highest levels of adduct were observed in non-smokers and non-occupationally exposed. Meat intake,
oils and fats were associated with higher levels of adducts, but all non-statistically significant. Higher intakes of calcium,
sodium and phosphorus were associated with lower adducts levels. Summarising, our study shows that bulky adducts measured
by 32P-postlabelling in DNA from WBC do not correlate with the usual diet of healthy Spanish adults. Although it has been proposed
that diet be the main source of PAH in nonsmokers without occupational exposure, DNA adducts do not seem to be suitable biomarkers
of dietary PAH in general population. 相似文献
998.
Antonio Bevilacqua Marianne Perricone Marianna Cannarsi Maria Rosaria Corbo & Milena Sinigaglia 《International Journal of Food Science & Technology》2009,44(11):2198-2207
This study focused to investigate the technological significance and the spoiling impact of diverse yeast strains, isolated from 'Bella di Cerignola' Italian table olives. Sixty-four isolates (belonging mainly to the species Candida famata and C. guilliermondii ) were studied to assess their growth at different temperatures (15, 25 and 37 °C), pHs (4.0, 5.0 and 9.5) and NaCl concentrations (0–10.0%) in lab medium. Their pectolytic, xylanolytic, lipolytic and catalase activities were also evaluated. Most of the yeasts showed a moderate pectolytic activity and were able to grow at pH 9.5 after 120 h of incubation. Salt and temperature were the most important environmental variables affecting yeast growth, which could exert a strong selective pressure on yeast population. Candida guilliermondii appeared more resistant to high salt concentrations, whereas C. famata was able to grow at 15 °C. 相似文献
999.
Antonio Ferrante Livia Martinetti & Tommaso Maggiore 《International Journal of Food Science & Technology》2009,44(5):1050-1056
Consumers are oriented towards fresh-cut vegetables that provide phytonutrients useful for preventing stress-related diseases. The aim of this work was to evaluate the cut operations on the quality changes of lamb's lettuce ( Valerianella olitoria L.) cv. Trofy during storage at 4 °C for 8 days. Results showed that chlorophyll and carotenoids reduction was observed after 8 days of storage. In both treatments, total carotenoids after 8 days decreased from 20 to 16 mg g−1 FW. Free and total phenols increased with storage in both treatments. Total phenols were 23% higher in control (32 μmol g−1 FW) compared to cut leaves (25 μmol g−1 FW) after 8 days of storage. Anthocyanins increased after 8 days and reached 30 mg 100 g−1 FW without significant difference between treatments. Ascorbic acid (AsA) and dehydroascorbic (DHA) acid increased in cut leaves compared to control. After 1 day AsA concentration was 3 300 nmol g−1 FW in cut leaves, while in control leaves was 1 500 nmol g−1 FW. Analogously AsA + DHA was higher in cut leaves, 4 100 nmol g−1 FW, while in control leaves the mean was 3 000 nmol g−1 FW. After 5 days of storage the values of AsA returned to initial values, while AsA + DHA were lower. 相似文献
1000.
Antonio Bevilacqua Milena Sinigaglia & Maria Rosaria Corbo 《International Journal of Food Science & Technology》2009,44(2):380-385
A three variables–five levels central composite design was used to study the effects of pH (3.5, 4.0, 4.5, 5.0 and 5.5), cinnamaldehyde (0, 40, 80, 120 and 160 ppm) and heating temperature (80, 84, 88, 92 and 96 °C) on the spores of Alicyclobacillus acidoterrestris in malt extract broth (MEB). The heat shock resulted in a slight decrease of spore number from 3.2 to 2.5 log CFU mL−1 and occurred at 80–85 °C depending on the pH of the medium. Otherwise, cinnamaldehyde acted as an additional hurdle within the storage time; the critical amounts to be used were included in the range 41.35–44.42 ppm of cinnamaldehyde and were related positively to the pH, i.e. the critical amount of active compound decreased with the decreasing of the pH. 相似文献