bluuebunny/crossref_metadata_2025_split huggingface dataset:
HAWT dynamic stall response asymmetries under yawed flow conditions
Authors: Schreck S. , Robinson M. , Hand M. , Simms D. 
Published: August 2002

AbstractHorizontal axis wind turbines can experience significant time‐varying aerodynamic loads, potentially causing adverse effects on structures, mechanical components and power production. As designers attempt lighter and more flexible wind energy machines, greater accuracy and robustness will become even more critical in future aerodynamics models. Aerodynamics modelling advances, in turn, will rely on more thorough comprehension of the three‐dimensional, unsteady, vortical flows that dominate wind turbine blade aerodynamics under high‐load conditions. To experimentally characterize these flows, turbine blade surface pressures were acquired at multiple span locations via the NREL Phase IV Unsteady Aerodynamics Experiment. Surface pressures and associated normal force histories were used to characterize dynamic stall vortex kinematics and normal force amplification. Dynamic stall vortices and normal force amplification were confirmed to occur in response to angle‐of‐attack excursions above the static stall threshold. Stall vortices occupied approximately one‐half of the blade span and persisted for nearly one‐fourth of the blade rotation cycle. Stall vortex convection varied along the blade, resulting in dramatic deformation of the vortex. Presence and deformation of the dynamic stall vortex produced corresponding amplification of normal forces. Analyses revealed consistent alterations to vortex kinematics in response to changes in reduced frequency, span location and yaw error. Finally, vortex structures and kinematics not previously documented for wind turbine blades were isolated. Published in 2000 by John Wiley & Sons, Ltd.
Horizontal axis wind turbine systems: optimization using genetic algorithms
Authors: Diveux T. , Sebastian P. , Bernard D. , Puiggali J. R. , Grandidier J. Y. 
Published: August 2002

AbstractA method for the optimization of a grid‐connected wind turbine system is presented. The behaviour of the system components is coupled in a non‐linear way, and optimization must take into account technical and economical aspects of the complete system design. The annual electrical energy cost is estimated using a cost model for the wind turbine rotor, nacelle and tower and an energy output model based on the performance envelopes of the power coefficient of the rotor, CP, on the Weibull parameters k and c and on the power law coefficient α of the wind profile. In this study the site is defined with these three parameters and the extreme wind speed Vmax. The model parameters vary within a range of possible values. Other elements of the project (foundation, grid connection, financing cost, etc.) are taken into account through coefficients. The optimal values of the parameters are determined using genetic algorithms, which appear to be efficient for such a problem. These optimal values were found to be very different for a Mediterranean site and a northern European site using our numerical model. Optimal wind turbines at the Mediterranean sites considered in this article have an excellent profitability compared with reference northern European wind turbines. Most of the existing wind turbines appear to be well designed for northern European sites but not for Mediterranean sites. Copyright © 2001 John Wiley & Sons, Ltd.
Fit of EDXRF spectra with a genetic algorithm
Authors: Brunetti Antonio , Golosio Bruno 
Published: August 2002

AbstractIn energy‐dispersive x‐ray fluorescence analysis, the estimation of the net area of the peaks is a primary requirement. This task requires a non‐linear fitting of the peaks. The most common procedures are based on the Marquardt– Levenberg technique. This technique generally works well only when the spectrum is perfectly known, i.e. all the peaks are recognized. Moreover, it is sometimes difficult to introduce constraints on the fit due to peak shape or other physical properties. In this paper a new technique is proposed, based on a set of genetic operators. It works well even when the knowledge of the peaks is incomplete and it also allows one easily to introduce constraints. The results obtained with this algorithm are generally superior with respect to a standard implementation of a Marquardt– Levenberg procedure. The only drawback is the speed of convergence, that is slower than in the Marquardt– Levenberg technique. Copyright © 2001 John Wiley & Sons, Ltd.
Application of J. E. Fernández algorithms in the evaluation of x‐ray intensities measured on fused glass discs for a set of international standards and a proposed calibration procedure
Authors: Malmqvist J. 
Published: August 2002

AbstractJ. E. Fernández algorithms, based on a solution of the Boltzmann transport equation describing the transport of photons in a specimen, are assembled in a computer program, MSXRF. The algorithms include different treatments of single and double photon collisions undergoing photoelectric, Rayleigh and/or Compton interactions, polarization effects and Compton broadening. The MSXRF program has been linked to another computer program, TNPP, governing input and output data, calibration parameters, choice of main elements etc.A slightly different approach to a calibration procedure is proposed, which makes use of the hybrid MSXRF‐TNPP program. This lining‐up procedure is based on measurement of a pure calibration standard and is a ‘one‐point’ determination of the analytical curve. The model is examined and adjusted by using a set of international standards covering a range from ppm levels to the highest concentrations. The same international standards are also used to control and describe the performance characteristics of the analytical method. The new calibration procedure is simpler in comparison with the earlier used.Analytical results, evaluated by the MSXRF‐TNPP program of measured CRM standards, have been compared with results from an earlier investigation, evaluated by the TNPP program only. The latter program is cruder in its design with regards to existing theories and setting of parameters and is not applicable over large concentration ranges without using correction factors for scattering and other specific effects. The results achieved were comparable to those from the production TNPP program.Problems such as the processing time, which is of utmost importance when applying a program in practice, is discussed. Today the evaluation time is unacceptable but an execution time of only a few minutes is reckoned to be good with new strategies. Copyright © 2001 John Wiley & Sons, Ltd.
Method for the calculation of the chemical composition of a thin film by Monte Carlo simulation and electron probe microanalysis
Authors: Hu Youhua , Pan Yinrong 
Published: August 2002

AbstractBased on a simplified Monte Carlo simulation model of electron scattering and characteristic x‐ray excitation of a multicomponent film on a substrate, a calculation method with an iteration approach was developed to transform the x‐ray intensity ratios measured by an electron probe microanalyzer into the chemical composition of the thin film on the substrate. The calculation of the characteristic fluorescence is also included in the simulation. The calculation results of compositions for several specimens agree well with measured data. Copyright © 2001 John Wiley & Sons, Ltd.
Multielemental x‐ray fluorescence analysis by using a non‐explicit description of the excitation beam
Authors: Barrea R. A. , Martínez V. Delgado , Plivelic T. S. 
Published: August 2002

AbstractThe fundamental parameters method has been extensively used for XRF analysis applications. One of the method's requirements is an explicit knowledge of the excitation beam used, which is not always available. Recently, a methodology that avoids the direct reconstruction of the x‐ray beam using a non‐explicit representation was published. In this paper the results of a multicomponent analysis of stainless‐steel samples with this methodology are presented. The concentrations obtained were compared with NBS certified values and very good agreement was found. Two parameteric models of beam description were also used in order to compare the goodness of each spectral representation (the non‐explicit model and the parametric ones) to perform x‐ray fluorescence analysis. The proposed methodology showed better results, in terms of accuracy and precision, than the standard methodology, in the case of a continuous spectrum of the exciting beam. When the spectrum of the exciting beam exhibits discontinuities (i.e. absorption edges and characteristic lines), the results of the three descriptions are comparable. It was demonstrated that the fundamental parameters method without an explicit knowledge of the excitation beam is suitable for use in x‐ray fluorescence analysis. Copyright © 2001 John Wiley & Sons, Ltd.
Theoretical model for the calculation of interference effects in TXRF and GEXRF
Authors: Pérez Roberto Daniel , Sánchez Héctor Jorge , Rubio Marcelo 
Published: August 2002

AbstractInterference effects between the contributions of transmitted and reflected radiation are observed during x‐ray propagation at grazing angles in stratified media. This phenomenon affects the fluorescence intensity in grazing incidence experiments [total reflection x‐ray fluorescence (TXRF)] and grazing emission experiments [grazing emission x‐ray fluorescence (GEXRF)], thus producing a characteristic interference pattern in the fluorescence spectra. The theoretical description of this effect can be studied by using models based on the general problem of an electromagnetic wave propagating through a stratified medium. In this work, a new approach to this problem is presented based on the development of approximations in the electric field. This approach uses a new theoretical formalism introduced recently. By using this new model, we proved that in order to evaluate the interference effects of an electric field in any surface layer, the influence of the surface layers over the layer analyzed can be neglected. By using this result, the precision obtained in the calculations of an electric field is acceptable. As an example, we present theoretical calculations for x‐ray propagation at glancing angles in testing stratified structures. The usual theoretical models for data analysis of TXRF and GEXRF experiments can be simplified by applying the present model. Furthermore, our results allow a better understanding of the experimental data obtained with both techniques. Copyright © 2001 John Wiley & Sons, Ltd.
Disruption and basic phenotypic analysis of six novel genes from the right arm of chromosome XII of Saccharomyces cerevisiae
Authors: Watson Martin D. 
Published: August 2002

AbstractSix open reading frames (ORFs) of unknown function from the right arm of Saccharomyces cerevisiae chromosome XII were deleted in two genetic backgrounds by disruption cassettes with regions of short flanking homology. This work was carried out within the framework of the EUROFAN consortium. The SFH disruption cassettes, obtained by PCR, were made by amplification of the kanMX marker module with oligonucleotides containing approximately 40 bp of homology to either the promoter or translation terminator regions of the relevant ORF. Transformants resistant to geneticin (G418) were selected. The SFH disruption cassettes were cloned into a bacterial vector. Each cognate gene was also cloned into a yeast centromeric plasmid. Sporulation and tetrad analysis of the disrupted heterozygous strains revealed that ORF YLR153c (now known as ACS2) is essential. Basic phenotypic analysis was performed on haploid deletants of both mating types of the five non‐essential ORFs, YLR082c (now known as SRL2), YLR149c, YLR151c, YLR152c and YLR154c. Plate growth tests on different media at 15°C, 30°C and 37°C did not reveal any significant differences between parental and mutant cells. Mating and sporulation efficiencies were not affected in any of the viable disruptants as compared to wild‐type cells. Copyright © 2001 John Wiley & Sons, Ltd.
At acidic pH, the GPA2–cAMP pathway is necessary to counteract the ORD1‐mediated repression of the hypoxic SRP1/TIR1 yeast gene
Authors: Bourdineaud J.‐P. 
Published: August 2002

AbstractThe hypoxic SRP1/TIR1 gene encodes a stress‐response cell wall mannoprotein and this gene is downregulated at acidic pH. The stress‐responsive HOG pathway is necessary to maintain hypoxic TIR1 expression, but only at acidic pH. However, unlike known HOG pathway‐dependent genes, TIR1 is under positive cAMP control and this effect is mediated by GPA2 but not by RAS2. Genetic analysis showed that ord1 mutation was epistatic to the gpa2 mutation, thereby indicating that Gpa2p is needed to counteract the Ord1 factor, which is involved in the repression of hypoxic TIR1 expression, while the HOG pathway appears to be independent from Ord1 repression. In addition, an increased ORD1 gene expression was observed in the Δgpa2 mutant cells, meaning that GPA2 maintains a low basal level of ORD1 transcripts. Thus, cAMP allows partial relief of the TIR1 repression exerted by Ord1p. However, this is contradicted at acidic pH by the HOG pathway requirement because Hog1p is activated under stress conditions when the cAMP cellular content is low. The opposite effects of the GPA2–cAMP and HOG pathways are likely to explain the diminished hypoxic expression of TIR1 at acidic pH. Copyright © 2001 John Wiley & Sons, Ltd.
Use of levonorgestrel as an effective means of contraception in the white‐faced saki (Pithecia pithecia)
Authors: Savage Anne , Zirofsky Dara S. , Shideler Susan E. , Smith Tessa E. , Lasley Bill L. 
Published: August 2002

AbstractThis study examines the use levonorgestrel (Norplant®‐2) as a means of contracepting white‐faced sakis (Pithecia pithecia). A 70‐mg silastic tubule of levonorgestrel was implanted subdermally between the scapulae in four multiparous and two nulliparous females. Implants remained in the females housed with males of proven fertility for 81 to 734 days. All females experienced low, acyclic levels of estrone conjugates (E1C, < 500 ng/mg Cr) and pregnanediol‐3‐glucuronide (PdG, < 1.5 μg/mg Cr) after insertion of the implant. In five females having nine contraceptive bouts, ovulation was completely blocked for the entire duration of Norplant insertion (range: 81–734 days) as evidenced by a lack of cyclic changes in excretory hormone levels. However, one female was observed to have cyclic ovarian hormonal levels 5.8 months after Norplant insertion. Thus, levonorgestrel can be an effective method for blocking cyclic ovarian hormonal changes for 1 year (n = 2) and possibly as long as 2 years (n = 3). Zoo Biol 21:49–57, 2002. © 2002 Wiley‐Liss, Inc.
Nest attendants in parakeet auklets
Authors: Grimes Julie , Logan Cheryl 
Published: August 2002

AbstractBreeding behaviors in a captive population of parakeet auklets (Cyclorrhynchus psittacula) were observed to determine whether a third bird present at the entrances to nest tunnels was a helper or competitor. Comparisons were made between focal pairs of nesting birds, two with and two without attendants. Pairs with attendants spent more time feeding and more time bathing and had less time with intruders (other than the third bird) at their tunnels. Nest attendants also helped in nest defense and incubation (taking some of the burden off the focal pair). Relatedness is unknown; therefore, kin selection cannot be assessed. Because all nest tunnels were occupied, however, limited breeding resources in the captive environment may make helping an adaptive alternative for mature birds. Zoo Biol 20:271–277, 2001. © 2001 Wiley‐Liss, Inc.
The SH-Verification Tool — Abstraction-Based Verification of Co-operating Systems
Authors: Ochsenschläger P. , Repp J. , Rieke R. , Nitsche U. 
Published: August 2002

Abstract.
The sh-verification tool comprises computing abstractions of finite-state behaviour representations as well as automata and temporal logic based verification approaches. To be suitable for the verification of so called co-operating systems, a modified type of satisfaction relation (approximate satisfaction) is considered. Regarding abstraction, alphabetic language homomorphisms are used to compute abstract behaviours. To avoid loss of important information when moving to the abstract level, abstracting homomorphisms have to satisfy a certain property called simplicity on the concrete (i.e. not abstracted) behaviour. The well known state space explosion problem is tackled by a compositional method combined with a partial order method.
Editorial
Authors: Groote Jan Friso , Luttik Bas , van Wamel Jos 
Published: August 2002

Formal Aspects of Computing
is devoted to the best papers presented at the third ERCIM workshop on Formal Methods for Industrial Critical Systems (FMICS98), held at the CWI in Amsterdam.
The FMICS workshops are intended to bring together scientists who are active in the area of formal methods and who are interested in exchanging their experiences in industrial usage of these methods. They also aim at the promotion of research and development for the improvement of the theory and their tools for industrial applications.
We are satisfied to see that time and again, the application of these methods clarifies the structure and inner workings of many systems and exposes many mistakes and conceptual errors. We are particularly delighted, as the reader may see when browsing through this special issue, that throughout the years a steady improvement can be observed regarding the size and complexity of systems that are being investigated. We hope and expect that this trend will continue throughout the forthcoming FMICS workshops.
We want to thank all those that have helped in producing this special issue. Especially the program committee, assisted by numerous referees, as well as the authors of the contributions and the participants of the workshop.
Probabilistic Duration Calculus for Continuous Time
Authors: Van Hung Dang , Chaochen Zhou 
Published: August 2002

Abstract.
This paper deals with dependability of imperfect implementations concerning given requirements. The requirements are assumed to be written as formulas in Duration Calculus. Implementations are modelled by continuous semi-Markov processes with finite state space, which are expressed in the paper as finite automata with stochastic delays of state transitions. A probabilistic model for Duration Calculus formulas is introduced, so that the satisfaction probabilities of Duration Calculus formulas with respect to semi-Markov processes can be defined, reasoned about and calculated through a set of axioms and rules of the model.
Computing Permutation Encodings
Authors: Leino K. Rustan M. 
Published: August 2002

Abstract.
A permutation can be encoded in several different ways. This paper discusses some relations among some encodings and how one can be computed from others. The paper shows a short proof of an existing efficient algorithm for encoding a permutation and presents two new efficient algorithms. One of the new algorithms is constructed as the inverse of an existing algorithm for decoding, making it the first efficient permutation encoding algorithm obtained in that way.
A Minimal Graphical User Interface for the Jape Proof Calculator
Authors: Bornat Richard , Sufrin Bernard 
Published: August 2002

Abstract.
GUI design isn't simply a matter of putting a nice front-end on a capable program. It requires thought about the way in which people might be expected to use a system, and investigation of the ways that they actually use it. Jape's GUI has been designed to be as simple as possible, so that it will not get in the way of the business of proof. It is designed to be minimal in the information that it displays and the gestures that it requires from the user. In this paper we introduce and give a rationale for the design of Jape's user interface, then note some of its drawbacks.
Are Patients with Multiple Endocrine Neoplasia Type I Prone to Premature Death?
Authors: Dean Patrick G. , van Heerden Jon A. , Farley David R. , Thompson Geoffrey B. , Grant Clive S. , Harmsen W. Scott , Ilstrup Duane M. 
Published: August 2002

AbstractMultiple endocrine neoplasia type I (MEN‐I) is an autosomal dominant disorder characterized by endocrinopathies involving the anterior pituitary gland, parathyroid glands, and pancreas. The long‐term prognosis for patients affected with this disorder is uncertain. To better characterize this prognosis, we performed a retrospective review of all patients with MEN‐I treated at a single institution during the period 1951–1997. A group of 233 patients served as the study population. Their records were analyzed for confirmation of diagnosis, treatments received, long‐term survival, and cause of death. Altogether, 108 eight male patients (46%) and 125 female patients (54%) were identified. At the conclusion of the study, 164 (70%) were alive and 69 (30%) were deceased, with a median follow‐up for patients alive at last contact of 13.4 years (range < 1 month to 54.3 years). The cause of death was reliably obtained in 60 patients. Of these patients, 17 (28%) died of causes related to MEN‐I, most commonly metastatic islet cell tumors (10 patients). The remaining patients died of causes unrelated to MEN‐I, most commonly coronary artery disease and nonendocrine malignancies (14% each). The overall 20‐year survival of MEN‐I patients was 64% (95% CI was 56–72%), and that of an age‐ and gender‐matched upper Midwest population was 81% (p < 0.001). Patients with MEN‐I appear to be at increased risk of premature death. Earlier diagnosis and treatment of potentially malignant pancreatic islet cell neoplasms may result in a decrease of this premature mortality.
Effects of Polyglycolic Acid and Polypropylene Meshes on Postoperative Adhesion Formation in Mice
Authors: Baykal Atac , Onat Demirali , Rasa Kemal , Renda Nurten , Sayek Iskender 
Published: August 2002

AbstractThe purpose of this study was to investigate the effects of polyglycolic acid (PGA), an absorbable (ABS) mesh, and polypropylene (PP), a nonabsorbable (NA) mesh, on intestinal adhesion formation. Altogether 72 mice were divided into a control group of 24, an ABS mesh group of 23, and an NA mesh group of 25. All three groups were divided into two subgroups for evaluation of adhesion severity at postoperative (po) days 5 and 90. Adhesion severity was measured with adhesion grading and tissue hydroxyproline (OHP) levels. Adhesion degree was minimal (1) in all subjects on day 5. Also there was no difference in tissue OHP levels between three groups on day 5
(
p > 0.05). Adhesion degree and tissue OHP levels as determinants of adhesion severity were higher in the PGA mesh group than the control group and the PP mesh group on day 90
(p < 0.001). There was no difference between the control group and the PP mesh groups (p > 0.05). Adhesion degree was higher on day 90 than on day 5 in the control group and the PGA mesh group (p < 0.05), whereas tissue OHP level was higher on day 90 than on day 5 in all three groups
(p < 0.001). Also there was linear correlation between adhesion degree and tissue OHP levels (r=
0.86, p < 0.001). The study demonstrates that ABS PGA mesh has higher potential for adhesion formation than the NA PP mesh, probably related to the increased foreign body and inflammatory reactions during the absorption process of the mesh.