bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conductive polymer composites (CPC): influence of processing conditions, shear rate and temperature on electrical properties of poly(butylene terephthalate)/poly(amide12‐b‐tetramethyleneglycol) – carbon black blends
Authors: Feller Jean‐François , Petitjean Énora 
Published: November 2003

AbstractConductive Polymer Composites (CPC) have been obtained by blending two immiscible polymers, poly(butylene terephthalate) (PBT) and poly(amide12‐b‐tetramethyleneglycol) (PEBAX) with carbon black (CB). The extrusion process allows to obtain anisotrope co‐continuous structures of various morphologies depending on composition and experimental conditions. It is possible to enhance CPC conductivity with appropriate processing temperature (Tp) and screw speed (Ω), without changing the composition of the blend. The best results are obtained with Ω =5 rpm and Tp=260°C. PBT/PEBAX‐CB resistivity evolution with Tp and Ω doesn't follow a linear law as expected from previous studies with poly(butylene terephthalate)/poly(ethylene)‐CB and poly(butylene terephthalate)/poly(ethylene‐co‐ethyl acrylate)‐CB systems. CB distribution has a more important impact on conductivity than polymers phase morphology. A good control of these parameters is essential to reproduce and optimize electrical properties.
Automated assessment of cervical dystonia
Authors: Galardi Giuseppe , Micera Silvestro , Carpaneto Jacopo , Scolari Silvana , Gambini Massimo , Dario Paolo 
Published: November 2003

AbstractWe developed an automated and objective method to measure posture and voluntary movements in patients with cervical dystonia using Fastrack, an electromagnetic system consisting of a stationary transmitter station and four sensors. The junction lines between the sensors attached to the head produced geometrical figures on which the corresponding aspects of the head were superimposed. The head position in the space was reconstructed and observed from axial, sagittal, and coronal planes. Four patients with cervical dystonia and 6 healthy subjects were studied. Each patient was representative of one of the typical patterns of cervical dystonia. The study allowed the authors to collect quantitative data on posture and range of motion of the head. This pilot study demonstrates the efficacy of the Fastrack system to objectively measure the head position in cervical dystonia patients. © 2003 Movement Disorder Society
Numerical finite element formulation of the Schapery non‐linear viscoelastic material model
Authors: Haj‐Ali Rami M. , Muliana Anastasia H. 
Published: November 2003

AbstractThis study presents a numerical integration method for the non‐linear viscoelastic behaviour of isotropic materials and structures. The Schapery's three‐dimensional (3D) non‐linear viscoelastic material model is integrated within a displacement‐based finite element (FE) environment. The deviatoric and volumetric responses are decoupled and the strain vector is decomposed into instantaneous and hereditary parts. The hereditary strains are updated at the end of each time increment using a recursive formulation. The constitutive equations are expressed in an incremental form for each time step, assuming a constant incremental strain rate. A new iterative procedure with predictor–corrector type steps is combined with the recursive integration method. A general polynomial form for the parameters of the non‐linear Schapery model is proposed. The consistent algorithmic tangent stiffness matrix is realized and used to enhance convergence and help achieve a correct convergent state. Verifications of the proposed numerical formulation are performed and compared with a previous work using experimental data for a glassy amorphous polymer PMMA. Copyright © 2003 John Wiley & Sons, Ltd.
An enriched meshless method for non‐linear fracture mechanics
Authors: Rao B. N. , Rahman S. 
Published: November 2003

AbstractThis paper presents an enriched meshless method for fracture analysis of cracks in homogeneous, isotropic, non‐linear‐elastic, two‐dimensional solids, subject to mode‐I loading conditions. The method involves an element‐free Galerkin formulation and two new enriched basis functions (Types I and II) to capture the Hutchinson–Rice–Rosengren singularity field in non‐linear fracture mechanics. The Type I enriched basis function can be viewed as a generalized enriched basis function, which degenerates to the linear‐elastic basis function when the material hardening exponent is unity. The Type II enriched basis function entails further improvements of the Type I basis function by adding trigonometric functions. Four numerical examples are presented to illustrate the proposed method. The boundary layer analysis indicates that the crack‐tip field predicted by using the proposed basis functions matches with the theoretical solution very well in the whole region considered, whether for the near‐tip asymptotic field or for the far‐tip elastic field. Numerical analyses of standard fracture specimens by the proposed meshless method also yield accurate estimates of the J‐integral for the applied load intensities and material properties considered. Also, the crack‐mouth opening displacement evaluated by the proposed meshless method is in good agreement with finite element results. Furthermore, the meshless results show excellent agreement with the experimental measurements, indicating that the new basis functions are also capable of capturing elastic–plastic deformations at a stress concentration effectively. Copyright © 2003 John Wiley & Sons, Ltd.
Interface current method for multi‐region neutron diffusion problems
Authors: Atalay M. A. , Aydin M. 
Published: November 2003

AbstractThis paper presents an interface current method for solving multi‐region neutron diffusion problems using multi‐dimensional Green's functions. The method is based on evaluation of the net currents at each interface. The unknown interface currents are expanded in terms of eigenfunctions. The orthogonality condition of the eigenfunctions is employed in order to transform these equations to an algebraic system. Numerical examples are provided at the end of the paper to demonstrate the validity of the method, and for comparison with the more established finite difference method. Copyright © 2003 John Wiley & Sons, Ltd.
Multiscale Galerkin method using interpolation wavelets for two‐dimensional elliptic problems in general domains
Authors: Jang Gang‐Won , Kim Jae Eun , Kim Yoon Young 
Published: November 2003

AbstractOne major hurdle in developing an efficient wavelet‐based numerical method is the difficulty in the treatment of general boundaries bounding two‐ or three‐dimensional domains. The objective of this investigation is to develop an adaptive multiscale wavelet‐based numerical method which can handle general boundary conditions along curved boundaries. The multiscale analysis is achieved in a multi‐resolution setting by employing hat interpolation wavelets in the frame of a fictitious domain method. No penalty term or the Lagrange multiplier need to be used in the present formulation. The validity of the proposed method and the effectiveness of the multiscale adaptive scheme are demonstrated by numerical examples dealing with the Dirichlet and Neumann boundary‐value problems in quadrilateral and quarter circular domains. Copyright © 2003 John Wiley & Sons, Ltd.
Incremental harmonic balance method with multiple time variables for dynamical systems with cubic non‐linearities
Authors: Pušenjak R. R. , Oblak M. M. 
Published: November 2003

AbstractThe incremental harmonic balance method with multiple time variables is developed for analysis of almost periodic oscillations in multi‐degree‐of‐freedom dynamical systems with cubic non‐linearities, subjected to the external multi‐tone excitation. The method is formulated to treat non‐autonomous as well as autonomous dynamical systems. The almost periodic oscillations, which coexist with periodic oscillations in a rotating system model with cubic restoring force and an electromagnetic eddy‐current damper are analysed. The closed form solutions based on generalized Fourier series containing two incommensurate frequencies are obtained in the case of small non‐dimensional stiffness ratio. Almost periodic oscillations of a rotating system model in dependence on variable parameters are also analysed, where solutions are computed through an augmentation process including a greater number of harmonics and combination frequencies involved. Copyright © 2003 John Wiley & Sons, Ltd.
Charts of fetal size: kidney and renal pelvis measurements
Authors: Chitty Lyn S. , Altman Douglas G. 
Published: November 2003

AbstractObjectiveTo construct new size charts for fetal kidney measurements and to define normal limits for renal pelvic antero‐posterior diameter.MethodsA prospective, cross‐sectional study was carried out in the ultrasound department of a large hospital. Six hundred and sixty‐three fetuses were scanned only once for the purpose of the study at gestations between 14 and 42 weeks. Centiles for kidney dimensions were estimated by combining separate fractional polynomial regression models fitted to the mean and standard deviation, assuming that the measurements have a normal distribution at each gestational age. Centiles for renal pelvic diameter were obtained using quantile regression.ResultsSize charts for fetal kidney dimensions [antero‐posterior (AP), transverse, length and volume] and renal pelvis diameter are presented and compared with previously published data.ConclusionWe present new size charts for fetal kidney size that take into consideration the increasing variability with gestational age. These data should aid the prenatal diagnosis of renal pathology by defining renal size and the upper limits of normal pelvic dilatation. They may be particularly useful in the third trimester where there is limited data available. Our data confirm that it is reasonable to use an upper limit of 7 mm for the AP diameter in late pregnancy. Copyright © 2003 John Wiley & Sons, Ltd.
Meconium peritonitis and pseudo‐cyst formation: prenatal diagnosis and post‐natal course
Authors: Eckoldt F. , Heling K. S. , Woderich R. , Kraft S. , Bollmann R. , Mau H. 
Published: November 2003

AbstractObjectivesIntra‐uterine bowel perforation can occur secondary to a variety of abnormalities and cause sterile peritonitis in the fetus (generalised = type I). If sealing of the perforation does not take place, a thick‐walled pseudo‐cyst can form (type II).MethodsOver a 12‐year period, 21 616 pregnancies were screened for gastro‐intestinal malformations using prenatal ultrasound. We identified 1077 cases suspicious of surgically correctable malformations. Post‐natal diagnoses and outcome were worked up retrospectively.ResultWe found 96 fetuses with suspected gastro‐intestinal malformations. Prenatal bowel perforation with meconium peritonitis was confirmed in 11 cases. In 5 of these 11, the correct diagnosis had been predicted prenatally. One child presented as a fetal and neonatal emergency (case report). Ten of the eleven infants were operated on during their first day of life. Intra‐operative findings were atresia (n = 4), meconium ileus (n = 6) and no obvious cause (n = 1). Two children suffered fatal complications.ConclusionMeconium peritonitis and meconium pseudo‐cysts as its special manifestation are assessable by prenatal diagnosis but present in different ways. They can present as fetal ascites or echogenic bowel and cause fetal or neonatal distress, requiring close observation and highly specialised care. Copyright © 2003 John Wiley & Sons, Ltd.
Detection of an aneurysm of the vein of Galen following signs of cardiac overload in a 22‐week old fetus
Authors: Hartung J. , Heling K. S. , Rake A. , Zimmer C. , Chaoui R. 
Published: November 2003

AbstractObjectivesTo present early prenatal diagnosis of an aneurysm of the Vein of Galen by detecting signs of cardiac overload in a 22‐week old fetus.CaseWe report on a 22‐week old fetus presenting with dilation of the heart, tricuspid and mitral valve regurgitation, reversed flow in the aortic arch and dilated neck vessels. Evaluation of the fetal brain revealed a dilated left ventricle, signs of brain hemorrhage and an anechoic structure between the two hemispheres.MethodsBy using the conventional Doppler technique, an intracerebral fistula and dilated vein of Galen was visualized. The complex vascular structure was demonstrated using 3‐D color power angiography (3‐D CPA). To our knowledge, this is the earliest diagnosis of this vascular malformation.ConclusionAlthough signs of cardiac overload rarely appear before the third trimester in cases of arteriovenous fistulae, it was shown that these signs could lead to the correct diagnosis of an aneurysm of the vein of Galen. Additionally, we show that 3‐D CPA is a promising technique to visualize complex vascular structures and make them easier to understand. Copyright © 2003 John Wiley & Sons, Ltd.
Sliding mode control of boost and buck‐boost power converters using the dynamic sliding manifold
Authors: Shtessel Yuri B. , Zinober Alan S. I. , Shkolnikov Ilia A. 
Published: November 2003

AbstractNon‐minimum phase tracking control is studied for boost and buck‐boost power converters. A sliding mode control algorithm is developed to track directly a causal voltage tracking profile given by an exogenous system. The approximate causal output non‐minimum phase asymptotic tracking in non‐linear boost and buck‐boost power converters is addressed via sliding mode control using a dynamic sliding manifold (DSM). Use of DSM allows the stabilization of the internal dynamics when the output tracking error tends asymptotically to zero in the sliding mode. The sliding mode controller with DSM links features of conventional sliding mode control (insensitivity to matched non‐linearities and disturbances) and a conventional dynamic compensator (accommodation to unmatched disturbances). Numerical examples demonstrate the effectiveness of the sliding mode controller even for a known time‐varying load. Copyright © 2003 John Wiley & Sons, Ltd.
A nonlinear set‐membership filter for on‐line applications
Authors: Scholte Eelco , Campbell Mark E. 
Published: November 2003

AbstractA guaranteed estimator for a general class of nonlinear systems and on‐line usage is developed and analysed. This filter bounds the linearization error, then applies a linear set‐membership filter such that stability guarantees hold for nonlinear systems. A tight bound on the linearization error is found using interval analysis. This filter recursively estimates an ellipsoidal set in which the true state lies. General assumptions include the use of bounded noises and twice continuously differentiable dynamics. When the system is uniformly observable, it is proven that the nonlinear set‐membership filter is stable. In addition, if no noise is present and the initial error is small, the error between the centre of the estimated set and the true value converges to zero. The result is an estimator which is computationally attractive and can be implemented robustly in real‐time. The proposed method is applied to a two‐state example to demonstrate the theoretical results. Copyright © 2003 John Wiley & Sons, Ltd.
Gastrectomy, peritonectomy, and perioperative intraperitoneal chemotherapy: The evolution of treatment strategies for advanced gastric cancer
Authors: Sugarbaker Paul H. , Yu Wansik , Yonemura Yutaka 
Published: November 2003

AbstractGastric cancer disseminates by hematogenous, lymphatic, and transcoelomic routes. For maximal containment of the malignant process, perioperative intraperitoneal chemotherapy is necessary in two groups of patients in whom the primary cancer can be resected. Those patients who have been resected for cure and have a high likelihood of microscopic residual disease require intraperitoneal chemotherapy. This includes all T3 and T4 patients, and patients with N2 nodes present. A series of randomized and nonrandomized clinical studies have established the benefits of perioperative intraperitoneal chemotherapy in this group of patients. Patients with stage IV disease who are able to undergo a palliative resection require these treatments if peritoneal seeding is observed. Systemic chemotherapy is largely ineffective for peritoneal seeding, while intraperitoneal chemotherapy is most likely to produce a response with small volume, surgically debulked carcinomatosis. In addition, intraperitoneal chemotherapy can eliminate the future development of debilitating ascites. Sufficient data are available from the gastric cancer literature to support the use of these combined treatments on a routine basis if the primary cancer is resectable and gastrointestinal function can be reestablished. Semin. Surg. Oncol. 21:233–248, 2003. © 2003 Wiley‐Liss, Inc.
Preoperative chemoradiation for locally advanced rectal cancer: rationale, technique, and results of treatment
Authors: Crane Christopher H. , Skibber John 
Published: November 2003

AbstractOver the past decade, 392 patients with stage II and III rectal cancer have been managed with preoperative chemoradiation and surgery at the M. D. Anderson Cancer Center (MDACC). Aggressive surgical techniques such as total mesorectal excision, proctectomy with coloanal anastamosis, and multivisceral excisions have been used. Initial pelvic chemoradiation is also used in patients who present with metastases. Preoperative chemoradiation followed by surgery has resulted in excellent sphincter preservation (SP) and pelvic control with minimal acute, perioperative, and late morbidity. SP has been achieved in greater numbers of patients over the past 3 years due to the increased use of coloanal anastamosis in very low tumors. There has been no increase in pelvic failure or perioperative morbidity with this practice. Patients with clinical T4 disease have significantly worse pelvic control. An assessment of the impact of CB on pelvic control and survival requires further follow‐up. Poor differentiation and poor response to preoperative therapy predict a worse overall survival. Durable symptom control without colostomy has been achieved using initial chemoradiation in patients who present with metastases. Aggressive bowel management and skin care can minimize hospitalization and treatment interruption due to acute toxicity. Multidisciplinary therapy using preoperative chemoradiation and aggressive surgery has resulted in excellent SP and pelvic control. However, more effective systemic therapies are needed, especially for patients who do not respond well to preoperative chemoradiation. Semin. Surg. Oncol. 21:265–270, 2003. © 2003 Wiley‐Liss, Inc.
The effects of an integrative supply chain strategy on customer service and financial performance: an analysis of direct versus indirect relationships
Authors: Vickery Shawnee K , Jayaram Jayanth , Droge Cornelia , Calantone Roger 
Published: November 2003

AbstractThis study examines the performance implications of an integrated supply chain strategy, with customer service performance followed by financial performance as performance constructs. Two major components of an integrated supply chain strategy are identified and defined: (1) integrative information technologies, which is modeled antecedent to (2) supply chain integration. The research model was tested using data from a sample (n=57) of the top 150 independent first tier automotive suppliers to the Big 3 in North America. The results showed positive direct relationships between (1) integrated information technologies and supply chain integration, (2) supply chain integration and customer service, and (3) customer service and firm performance. The relationship of supply chain integration to financial performance was indirect, through customer service; i.e., customer service was found to fully (as opposed to partially) mediate the relationship between supply chain integration and firm performance for first tier suppliers in the automotive industry.
The survivorship bias, share price effect, and small firm effect in Canadian markets
Authors: Elfakhani Said , Wei Jason 
Published: November 2003

AbstractAfter controlling for survivorship bias, we examine the relation between average returns, firm size, and price levels for Canadian stocks during the 1975–1994 period. Our findings indicate that there is a significant inverse share price level effect in Canadian markets. When we compare the results of the overall sample with the groups of surviving firms and delisted stocks, the latter group shows strong performance for large‐size, high‐priced stocks. Evidence that supports an independent size effect is less clear for Canadian stocks. A small size effect exists only among the higher share price denominations, which suggests a confounded size‐price effect. Although the delisted group returns are statistically different from those of the survivor and the overall groups, which implies some evidence of survivorship bias, the difference between the survivor group and the overall group is weak at best.
Tribal Participatory Research: Mechanisms of a Collaborative Model
Authors: Fisher Philip A. , Ball Thomas J. 
Published: November 2003

AbstractAlthough much social science research has been conducted within American Indian and Alaska Native (AIAN) communities, relatively little research has been conducted by or for those communities. We describe an approach that facilitates the active involvement of AIAN communities in the research process, from conceptualizing the issues to be investigated to developing a research design, and from collecting, analyzing, and interpreting the data to disseminating the results. The Tribal Participatory Research (TPR) approach is consistent with recent developments in psychology that emphasize the inclusion of community members and the social construction of knowledge. We describe the foundations of the approach and present specific mechanisms that can be employed in collaborations between researchers and AIAN communities. We conclude with a discussion of the implications of the use of TPR regarding project timelines and budgets, interpretation of the data, and ultimately the relationships between tribes and researchers.
Reconceptualizing Quantitative and Qualitative Methods: A Case Study Dealing with Place as an Exemplar
Authors: Langhout Regina Day 
Published: November 2003

AbstractA useful framework for understanding methods is to think of them as being on a continuum of holistic and pattern focused to particularistic and specific. This paper argues for this conceptualization rather than thinking of quantitative and qualitative methods as oppositional and potentially contradictory. A case study provides an example of using both quantitative and qualitative methods in a holistic and pattern‐focused study, while also attending to the values and goals of community psychology. The substantive research goal is to understand a child's experience of places related to school. Methods include ethnographic long‐term participation and observation, interviews, multidimensional scaling, and social network analysis. Most quantitative method variables are generated from study participant; no outside structure is imposed. The quantitative methods extend and inform the qualitative methods, just as the qualitative methods extend and inform the quantitative methods. The quantitative and qualitative methods work reciprocally to extend and inform each other.