bluuebunny/crossref_metadata_2025_split huggingface dataset:
Large displacement FEM modelling of the cone penetration test (CPT) in normally consolidated sand
Authors: Susila Endra , Hryciw Roman D. 
Published: May 2003

AbstractA new finite element model based on a large strain formulation has been developed to study cone penetration in normally consolidated sand. An auto‐adaptive remeshing technique was utilized for handling the very large distortion of sand surrounding the cone tip. A frictional contact interface utilizing Mohr–Coulomb's theory was chosen to represent interactions between the surface of the cone and sand. To model the sand behaviour, the non‐associated Drucker–Prager constitutive model was selected. ABAQUS, a commercial finite element software package, was used to implement the model. The explicit solution algorithm was chosen due to its effectiveness for complicated contact problems. Analysis results proved that the model successfully captured the cone penetration behavior in sand. In addition, a chart to predict internal friction angles based on cone tip resistance for different vertical effective stresses was provided. This paper also shows a typical distribution of sleeve resistance, tip resistance—penetration relationship, and typical contours of vertical, horizontal, and shear stresses in normally consolidated sand. Finally, a non‐uniform resistance was found along the length of the friction sleeve. Copyright © 2003 John Wiley & Sons, Ltd.
Correction to the gas phase pressure term in the continuum model for partially saturated granular media presented by Pietruszczak and co‐workers
Authors: Iveson Simon M. 
Published: May 2003

AbstractPietruszczak and coworkers (Internat. J. Numer. Anal. Methods Geomech. 1994; 18(2):93–105; Comput. Geotech. 1991; 12( ):55–71) have presented a continuum‐based model for predicting the dynamic mechanical response of partially saturated granular media with viscous interstitial liquids. In their model they assume that the gas phase is distributed uniformly throughout the medium as discrete spherical air bubbles occupying the voids between the particles. However, their derivation of the air pressure inside these gas bubbles is inconsistent with their stated assumptions. In addition the resultant dependence of gas pressure on liquid saturation lies outside of the plausible range of possible values for discrete air bubbles. This results in an over‐prediction of the average bulk modulus of the void phase. Corrected equations are presented. Copyright © 2003 John Wiley & Sons, Ltd.
Consistent mesh tying methods for topologically distinct discretized surfaces in non‐linear solid mechanics
Authors: Laursen T. A. , Heinstein M. W. 
Published: May 2003

AbstractThis work presents a new technique for joining dissimilar meshes in non‐linear finite element analysis, with the novel result that the adjoining surfaces do not need to be spatially coincident for patch tests to be passed. The work builds in some sense on results previously presented by Dohrmann et al. (International Journal for Numerical Methods in Engineering 1991; 40:1205), but considerably generalizes upon the results presented there. Most importantly, it is shown that consistency of the tied finite element formulation may be achieved such that implementation of element formulations is not affected, through the use of a three‐field variational principle applied over the contacting region. A key conclusion of the work is that although the approach advocated bears some resemblance to mortar element schemes for contact analysis (see, for example, McDevitt and Laursen, International Journal for Numerical Methods in Engineering 2000; 48:1525), a straightforward application of a mortaring scheme is not sufficient to guarantee patch test passage when dissimilar meshing of curved surfaces leads to local open volumes (or overlaps) between tied surfaces in their reference configurations. The proposed algorithm is demonstrated through a number of numerical examples performed within a matrix‐free non‐linear equation solving framework. Published in 2003 by John Wiley & Sons, Ltd.
Variational multiscale methods to embed the macromechanical continuum formulation with fine‐scale strain gradient theories
Authors: Garikipati K. 
Published: May 2003

AbstractA variational basis is presented to link fine‐scale theories of material behaviour with the classical, macromechanical continuum theory. The approach is based on the weak form of the linear momentum balance equations, and a separation of the weighting function and displacement fields into coarse and fine‐scale components. Coarse and fine‐scale weak forms are defined. The latter is used to introduce a strain gradient theory that operates at finer scales of deformation. Attention is focused upon applications requiring the enhanced physical accuracy of the fine‐scale strain gradient theory, without the computational cost of discretization that spans the range from coarse to fine scales. A variationally consistent method is developed to embed the fine‐scale strain gradient theory in the macromechanical formulation. The embedding is achieved by eliminating the fine‐scale displacement field from the problem. Two examples demonstrate the numerical efficiency of the method, while retaining physical and mathematical properties of the fine‐scale strain gradient theory. Copyright © 2003 John Wiley & Sons, Ltd.
Exponential convergence and H‐c multiquadric collocation method for partial differential equations
Authors: Cheng A. H.‐D. , Golberg M. A. , Kansa E. J. , Zammito G. 
Published: May 2003

AbstractThe radial basis function (RBF) collocation method uses global shape functions to interpolate and collocate the approximate solution of PDEs. It is a truly meshless method as compared to some of the so‐called meshless or element‐free finite element methods. For the multiquadric and Gaussian RBFs, there are two ways to make the solution converge—either by refining the mesh size h, or by increasing the shape parameter c. While the h‐scheme requires the increase of computational cost, the c‐scheme is performed without extra effort. In this paper we establish by numerical experiment the exponential error estimate ϵ ∼ O(λ√c̄h) where 0 < λ < 1. We also propose the use of residual error as an error indicator to optimize the selection of c. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 571–594, 2003
Exponential meshes and three‐dimensional computation of a magnetic field
Authors: Alouges F. , Laminie J. , Mefire S. M. 
Published: May 2003

AbstractWe describe the simulation of an exterior problem using a magnetic field deriving from magnetostatics, with a numerical method mixing the approaches of C. I. Goldstein and L.‐A. Ying. This method is based on the use of a graded mesh obtained by gluing homothetic layers in the exterior domain. On this mesh, we use an edge elements discretization and a recently proposed mixed formulation. In this paper, we provide both a theoretical and numerical study of the method. We establish an error estimate, describe the implementation, propose some preconditioning techniques and show the numerical results. We also compare these results with those obtained from an equivalent boundary elements approach. In this way, we retain that our method leads to a practical numerical implementation, a saving of storage, and turns out to be an alternative to the classical boundary elements method. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 595–637, 2003
The modified characteristic finite difference fractional steps method for the coupled system of fluid dynamics in porous media and its analysis
Authors: Yuan Yirang 
Published: May 2003

AbstractFor the coupled system of multilayer fluid dynamics in porous media, the modified characteristic finite difference fractional steps method applicable to parallel arithmetic is put forward and two‐dimensional and three‐dimensional schemes are used to form a complete set. Some techniques, such as calculus of variations, energy method, piecewise biquadratic interpolation, multiplicative commutation rule of difference operators, decomposition of high order difference operators and prior estimates are adopted. Optimal order estimates in L2 norm are derived to determine the error in the approximate solution. This method has already been applied to the numerical simulation of multilayer fluid dynamics in porous media. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 665–681, 2003.
Localized triangular differential quadrature
Authors: Zhong Hongzhi , Hua Yongxia , He Yuhong 
Published: May 2003

AbstractA localized triangular differential quadrature method is introduced in this article. Not only is the existing limitation on the approximation order in the triangular differential quadrature eliminated but also the convergent rate is enhanced in the new method. As an example to validate the new method, elastic torsion of prismatic shaft with regular polygonal cross section is studied and excellent agreement with available theoretical and analytic solutions is reached. It is believed that the present work further widens the applicability of the triangular differential quadrature technique. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 682–692, 2003
Software modelling of grid‐connected photovoltaic buildings
Authors: Argul F. J. , Castro M. , Delgado A. , Carpio J. , Peire J. 
Published: May 2003

AbstractThis paper presents a software tool, freely available on the Worldwide Web, that can be concurrently run by multiple users on different hardware–software platforms. To evaluate the limits and competitiveness of PV energy in Spain, several companies, utilities and institutions have been working together in a project called FotoRED. Within this project, several computer tools have been developed to analyse the potential of connecting photovoltaic stations to the utility grid. One of these tools is the simulator presented here, a program to estimate the energy balance and economic behaviour of grid‐connected PV buildings. Depending on several construction parameters of the building, the photovoltaic generators installed, the geographical location, weather conditions, etc., the program estimates the energy consumed in the building, the photovoltaic energy that can be generated on‐site and the resulting energy balance on a daily, monthly and yearly basis. The economic behaviour of the building can also be simulated over a 30‐year period, generating cash‐flow diagrams, investment payback curves and other economic information to describe the building's expected performance. Many building designs and several existing buildings have been simulated with this tool so far. One example of these is presented and the conclusions reached during several simulation runs are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Properties of 19.2% efficiency ZnO/CdS/CuInGaSe2thin‐film solar cells
Authors: Ramanathan Kannan , Contreras Miguel A. , Perkins Craig L. , Asher Sally , Hasoon Falah S. , Keane James , Young David , Romero Manuel , Metzger Wyatt , Noufi Rommel , Ward James , Duda Anna 
Published: May 2003

AbstractWe report the growth and characterization of record‐efficiency ZnO/CdS/CuInGaSe2thin‐film solar cells. Conversion efficiencies exceeding 19% have been achieved for the first time, and this result indicates that the 20% goal is within reach. Details of the experimental procedures are provided, and material and device characterization data are presented. Published in 2003 by John Wiley & Sons, Ltd.
Stress manifestation in high school students: An Australian sample
Authors: Moulds John D. 
Published: May 2003

AbstractStress symptoms associated with main daily hassles were assessed among grades 7, 9 and 11 students in all‐female, all‐male, and coeducational Catholic high schools in Western Sydney, Australia. Factor analysis identified the stress manifestation domains of anxiety, anger, and physiological arousal. Differences in these are examined and a conceptual model of stress manifestation is proposed. Implications of the findings for school‐based stress management programs are addressed. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 391–402, 2003.
Sources of variance in curriculum‐based measures of silent reading
Authors: Brown‐Chidsey Rachel , Davis Linda , Maya Cynthia 
Published: May 2003

AbstractCurriculum‐Based Measurement silent reading (CBM‐SR) items have been found to be reliable and valid for measuring reading comprehension skills This generalizability study reports the findings from administration of three CBM‐SR passages to fifth through eighth grade students in one school district. Using Repeated Measures Analyses of Variance (RMANOVA) procedures, the statistical probability of performance on the CBM‐SR task as a differential indicator of reading comprehension skill was found to be significant among students in different grade levels and between students who did and did not receive special education services. Follow‐up analyses were conducted using generalizability theory to estimate the amount of variance in CBM‐SR scores from individual score differences, grade levels, and special education status. The results indicated that on two of the passages, variability in CBM‐SR scores came primarily from grade level differences in scores on the tasks, while on the third passage, the differences were most attributable to individual differences in scores, regardless of grade level or special education services. Implications for the use of CBM‐SR items for routine assessment of students' reading skills are discussed. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 363–377, 2003.
A school‐based violence prevention model for at‐risk eighth grade youth
Authors: Rollin Stephen A. , Kaiser‐Ulrey Cheryl , Potts Isabelle , Creason Alia Haque 
Published: May 2003

AbstractThis study examined the effectiveness of a school and community‐based violence prevention program for at‐risk eighth‐grade students in three public schools in Florida. School officials matched intervention students with community‐based mentors in an employment setting to allow targeted youth to explore careers and receive one‐on‐one intervention from an adult mentor. Intervention students were compared to a control group of students not receiving mentorship services. This study used MANOVA and t‐test analyses to examine six outcomes measured: (1) unexcused absences; (2) number of in‐school suspensions; (3) number of days of in‐school suspensions; (4) number of out‐of‐school suspensions; (5) number of days of out‐of‐school suspensions; and (6) total number of infractions committed on school property. The findings suggested that mentored students, as compared to control group students, had significant reductions in total number and days of suspensions, days of sanction, and infractions committed on school property. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 403–416, 2003.
New aliphatic poly(ester‐carbonates) based on 5‐methyl‐5‐allyloxycarbonyl‐1,3‐dioxan‐2‐one
Authors: Mullen Brian D. , Tang Chau N. , Storey Robson F. 
Published: May 2003

AbstractThe synthesis, characterization, and ring‐opening polymerization of a new cyclic carbonate monomer containing an allyl ester moiety, 5‐methyl‐5‐allyloxycarbonyl‐1,3‐dioxan‐2‐one (MAC), was performed for the first time. MAC was synthesized in five steps in good yield beginning from the starting material, 2,2‐bis(hydroxymethyl)propionic acid. Subsequent polymerization and copolymerizations of the new cyclic carbonate with rac‐lactide (rac‐LA) and ϵ‐caprolactone (CL) were attempted. Rac‐LA copolymerized well with MAC, but CL copolymerizations produced insoluble products. Oligomeric macroinitiators of MAC and rac‐LA were synthesized from stannous ethoxide, and both macroinitiators were used for the controlled ring‐opening polymerization of rac‐LA. The polymerization kinetics were examined by monitoring the disappearance of the characteristic CO ring stretch of the monomer at 1240 cm−1 with real‐time in situ Fourier transform infrared spectroscopy. Postpolymerization oxidation reactions were conducted to epoxidize the unsaturated bonds of the MAC‐functionalized polymers. Epoxide‐containing polymers may allow further organic transformations with various nucleophiles, such as amines, alcohols, and carboxylic acids. NMR was used for microstructure identification of the polymers, and size exclusion chromatography and differential scanning calorimetry were used to characterize the new functionalized poly(ester‐carbonates). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1978–1991, 2003
Vinyl‐type polymerization of norbornene by nickel(II) bisbenzimidazole catalysts
Authors: Patil Abhimanyu O. , Zushma Stephen , Stibrany Robert T. , Rucker Steven P. , Wheeler Louise M. 
Published: May 2003

AbstractNovel nickel(II) bisbenzimidazole complexes were prepared via a three‐step synthetic procedure consisting of aniline/diacid condensation, ligand N‐alkylation, and metal complexation. The complexes were characterized by X‐ray crystallography and found to possess a pseudotetrahedral geometry. Upon activation with methylaluminoxane, these nickel bisbenzimidazoles did not polymerize simple olefins (e.g., ethylene, propylene, and 1‐butene) but were found to carry out the rapid and efficient polymerization of norbornene. The polynorbornene products were characterized by gel permeation chromatography/light scattering, 13C NMR, and IR, and their Mark–Houwink and dn/dc parameters were determined. The molecular weights of the polynorbornenes were very high (weight‐average molecular weight = 587,000–797,000 g/mol). 13C NMR suggested that the polymerization occurred via vinyl addition (i.e., a 2,3‐linked polymer); no ring‐opened product was observed. Thermogravimetric analysis indicated that the polynorbornenes were stable up to 400 °C under nitrogen. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2095–2106, 2003
Synthesis of poly(chitosan‐N‐isopropylacrylamide) complex particles with the method of soapless dispersion polymerization
Authors: Lee Chia‐Fen , Wen Chia‐Jen , Chiu Wen‐Yen 
Published: May 2003

AbstractCrosslinked poly(chitosan‐N‐isopropylacrylamide) [poly(NIPAAM‐chitosan)] complex particles were successfully synthesized with the method of soapless dispersion polymerization. The anionic initiator ammonium persulfate (APS) and the cationic initiator 2,2′‐azobis(2‐methylpropionamidine) dihydrochloride (AIBA) were used to initiate the copolymerization. The poly(NIPAAM‐chitosan) copolymer particles synthesized with APS as the initiator had a homogeneous morphology, whereas the copolymer particles synthesized with AIBA as the initiator showed a core–shell morphology. In addition, various variables such as the particle size, reaction rate, and ζ potential were taken into account. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2053–2063, 2003
Synthesis of polyesters with pendant oxetane groups by the chemoselective alternating copolymerization of 3‐ethyl‐3‐(glycidyloxymethyl)oxetane with carboxylic anhydride and its photochemical reaction
Authors: Kudo Hiroto , Ueda Kensuke , Sano Naotaka , Nishikubo Tadatomi 
Published: May 2003

AbstractThe synthesis of polyesters with pendant oxetane groups by the chemoselective alternating copolymerization of 3‐ethyl‐3‐(glycidyloxymethyl)oxetane (EGMO) with carboxylic anhydride and the photochemical reaction of the resulting polymer was examined. The alternating copolymerization of EGMO with phthalic anhydride proceeded chemoselectively with quaternary onium salts under appropriate reaction conditions, and the corresponding soluble polymers with pendant oxetane groups with number‐average molecular weights of 4700–7200 were obtained in 72–87% yields. Furthermore, the photochemical reaction of the resulting polymers was examined with certain photoacid generators in the film state upon UV irradiation, and it was found that the photocrosslinking reaction of the pendant oxetane groups proceeded smoothly to give the insoluble polymers. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1952–1961, 2003
Anionic polymerization of methyl methacrylate initiated with late transition‐metal halides/organolithium/triisobutylaluminum systems
Authors: Ihara Eiji , Todaka Tsuyoshi , Inoue Kenzo 
Published: May 2003

AbstractAnionic polymerization of methyl methacrylate (MMA) initiated with late transition‐metal halides [manganese chloride (MnCl2), iron dichloride (FeCl2), iron trichloride (FeCl3), cobalt chloride (CoCl2), or nickel bromide (NiBr2)]/organolithium [nButyllithium (nBuLi) or phenyllithium (PhLi)]/triisobutylaluminum (iBu3Al) systems is described. Except for the system with NiBr2, the polymerizations of MMA afforded narrow molecular weight distribution poly(methyl methacrylate)s (PMMAs) with high molecular weights in quantitative yields at 0 °C in toluene. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) analyses of the PMMAs obtained by the systems with FeCl2, FeCl3, and CoCl2 revealed that the polymers had hydrogen (H) at both chain ends. Accordingly, the reaction of the transition‐metal halides with the organolithium in the presence of iBu3Al should result in the formation of transition‐metal hydride [M‐H]− species, which was nucleophilic enough to initiate the MMA polymerization. Because the presence of a six‐membered cyclic structure resulting from backbiting was confirmed from the MALDI‐TOF MS analyses of the PMMA obtained with the metal halide (FeCl2, FeCl3, or CoCl2)/organolithium systems in the absence of iBu3Al, the introduction of H at the ω‐chain end indicated that iBu3Al should prevent the backbiting. However, the MnCl2/nBuLi/iBu3Al initiating system gave PMMAs bearing H at the α chain end and six‐membered cyclic structure at the ω chain end. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1962–1977, 2003
Synthesis, characterization, and biological activity of N‐(4‐acetylphenyl)maleimide and its oxime, carbazone, thiosemicarbazone derivatives and their polymers
Authors: Soykan Cengiz , Erol İbrahim 
Published: May 2003

AbstractA new type of maleimide monomer, N‐(4‐acetylphenyl)maleimide (NAPMI), was synthesized. The oxime, carbazone, and thiosemicarbazone derivatives of NAPMI were prepared with hydroxylamine hydrochloride, semicarbazide hydrochloride, and thiosemicarbazide hydrochloride, respectively. Radical homopolymerization of NAPMI and its derivatives were prepared at 60 °C in dimethyl sulfoxide solution with azobisisobutyronitrile as an initiator. The monomers and theirs homopolymers were characterized with Fourier transform infrared and NMR techniques. The glass‐transition temperatures, thermal stability, and ultraviolet stability of the polymers are compared. The activation energies of the thermal degradation of polymers were calculated by the Kissinger method. The antibacterial and antifungal effects of the monomers and polymers were also investigated on various bacteria and fungi. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1942–1951, 2003