bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancement of waveguide model for propagation‐loss prediction in tunnels
Authors: Zhang Y. P. 
Published: June 2004

AbstractFor microcellular system design, we have enhanced a well‐known waveguide model for propagation‐loss prediction along an LOS propagation path in a tunnel. It is reported in this letter. The enhancement involves a more accurate calculation of the tilt loss, the distinction of the two propagation regions, and the suggestion of using the free‐space model for one region and the waveguide model for the other. The enhancement is demonstrated with examples. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 10–12, 2001.
Quasi‐TEM analysis of a novel coplanar waveguide and coupled structure
Authors: Zhou Xilang , Chen Jinghua , Chen Zhongqiang 
Published: June 2004

AbstractA novel coplanar waveguide (CPW) and coupled structure with a cylindrical conductor as the shielding are proposed. Simple analytic formulas for the capacitance per unit length and characteristic impedance of the structure are derived using the conformal mapping technique. The numerical results are in good agreement with those obtained by other authors. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 49–51, 2001.
Uniplanar four‐element Vivaldi array fed by a coplanar waveguide
Authors: Linardou I. , Migliaccio C. 
Published: June 2004

AbstractThis letter describes the design of a uniplanar parallel‐series‐fed linear array of Vivaldi antennas. Matching conditions have been optimized with an equivalent‐circuit model. The array exhibits 12dBi gain in the substrate plane, 80% radiation efficiency, and low cross polarization over 5% bandwidth centered at 4.2GHz. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 60–62, 2001.
Relationship between thermally induced lensing and output power for a high‐power laser‐diode side‐pumped solid‐state laser
Authors: Yu Deli , Tang D. Y. 
Published: July 2004

AbstractThe variable focal length of thermal lensing in grains of a thermally loaded Nd:YAG crystal rod have been calculated and compared with the measurements of our system. By use of the space‐dependent rate equations, the analytical expression of the output power on the pump power, which consists of the factors of threshold volume and the focal length of thermal lensing, is presented. We investigate the threshold pump power, and the relationships between the output power and the pumping power under different lengths of thermal lensing. Experimental results concerning the output power of fundamental mode and the pump power, which are related to the thermal lensing and agreeable to the theoretical analysis are given. Finally, the optimized experimental output power of our laser system is obtained. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 361–365, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20305
Full‐wave analysis of industrial microwave applicators: TM modes
Authors: Lohr C. , Pribetich P. , Stuerga D. 
Published: July 2004

AbstractA full‐wave analysis of TM modes (dispersion characteristics and field configurations) is presented for industrial devices able to heat pipes filled with lossy fluids such as water. These results are obtained by a numerical simulation based on the residue theory. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 365–369, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20306
EBG at microwave frequency range: Bragg and/or resonant effect?
Authors: Ibáñez Loinaz Asier , del Río Bocio Carlos 
Published: July 2004

AbstractA rigorous consideration of the filtering effect of EBG structures at the microwave‐frequency range will be performed in this paper. We will show that, in this frequency range, the periodic‐structure filtering (or Bragg effect) and the self‐resonance of the different cells involved are tuned approximately at the same frequencies; thus, their influences are mixed in the final filter response. Both effects are defined by different geometrical laws and this is probably the main reason not to use a standard design method for a given filter requirement when using these technologies. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 383–385, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20311
Parabolic‐equation‐based study of ducting effects on microwave propagation
Authors: Sirkova I. , Mikhalev M. 
Published: July 2004

AbstractThis work reports a quantitative assessment of propagation losses for the frequency band 2110–2170 MHz under evaporation and surface‐based ducts conditions. Flat‐underlying‐surface and elevated‐terrain cases are studied. The calculations are based on the parabolic approximation to the wave equation in conjunction with finite‐element and Fourier split‐step techniques. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 390–394, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20314
Enhanced fractal microstrip‐antenna performance by using photonic‐bandgap fractal ground plane
Authors: Siakavara K. 
Published: July 2004

AbstractIn this paper, a Van Koch printed antenna on a photonic‐bandgap fractal substrate is presented. The substrate is designed with grounded Van Koch printed elements. The structure is a multifrequency radiator as a common fractal antenna, but the special synthesis of the substrate enhances the frequency bandwidth and gain, and drives the antenna to radiate a circularly polarized field. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 397–402, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20316
Continuous dynamics for a linear coupled‐oscillator array with peripheral coupling‐phase adjustments
Authors: Yoon Jung Ho , Myung Noh‐Hoon 
Published: July 2004

AbstractA continuum model of the dynamics for a coupled‐oscillator array that presents an intuitive insight into the behavior of the frequency‐tuned array was introduced recently. In this paper, we further develop the continuous dynamics for the coupled‐oscillator array with a coupling‐phase adjustment of the coupling circuit at the peripheries of the array. The adjustment is verified by related experimental measurements. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 422–425, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20324
Bifrequency behaviour and bandwidth enhancement of a dielectric resonator antenna
Authors: Nannini C. , Ribero J. M. , Dauvignac J. Y. , Pichot Ch. 
Published: July 2004

AbstractIn this paper, we present a new configuration which enhances the impedance bandwidth (we obtain an increase of 80%) and exhibits dual‐frequency operation. The characteristics of the new structure are measured and discussed. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 432–434, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20327
Shear band evolution and accumulated microstructural development in Cosserat media
Authors: Tordesillas A. , Peters J. F. , Gardiner B. S. 
Published: July 2004

AbstractThis paper prepares the ground for the continuum analysis of shear band evolution using a Cosserat/micropolar constitutive equation derived from micromechanical considerations. The nature of the constitutive response offers two key advantages over other existing models. Firstly, its non‐local character obviates the mathematical difficulties of traditional analyses, and facilitates an investigation of the shear band evolution (i.e. the regime beyond the onset of localization). Secondly, the constitutive model parameters are physical properties of particles and their interactions (e.g. particle stiffness coefficients, coefficients of inter‐particle rolling friction and sliding friction), as opposed to poorly understood fitting parameters. In this regard, the model is based on the same material properties used as model inputs to a discrete element (DEM) analysis, therefore, the micromechanics approach provides the vehicle for incorporating results not only from physical experiments but also from DEM simulations. Although the capabilities of such constitutive models are still limited, much can be discerned from their general rate form. In this paper, an attempt is made to distinguish between those aspects of the continuum theory of localization that are independent of the constitutive model, and those that require significant advances in the understanding of micromechanics. Copyright © 2004 John Wiley & Sons, Ltd.
Steady infiltration from buried point source into heterogeneous cross‐anisotropic unsaturated soil
Authors: Chen G. J. , Gallipoli D. 
Published: July 2004

AbstractThe paper presents the analytical solution for the steady‐state infiltration from a buried point source into two types of heterogeneous cross‐anisotropic unsaturated half‐spaces. In the first case, the heterogeneity of the soil is modelled by an exponential relationship between the hydraulic conductivity and the soil depth. In the second case, the heterogeneous soil is represented by a multilayered half‐space where each layer is homogeneous. The hydraulic conductivity varies exponentially with moisture potential and this leads to the linearization of the Richards equation governing unsaturated flow. The analytical solution is obtained by using the Hankel integral transform. For the multilayered case, the combination of a special forward and backward transfer matrix techniques makes the numerical evaluation of the solution very accurate and efficient. The correctness of both formulations is validated by comparison with alternative solutions for two different cases. The results from typical cases are presented to illustrate the influence on the flow field of the cross‐anisotropic hydraulic conductivity, the soil heterogeneity and the depth of the source. Copyright © 2004 John Wiley & Sons, Ltd.
Political Reform and the Future of American Democracy
Authors: Bradley Bill , Gates Christopher T. 
Published: July 2004

AbstractWe live in a rapidly changing world, yet our political systems and structures seem painfully out of date. The role of money continues to raise questions about the fairness of electoral politics, much as it did at the dawn of the Progressive Era, one hundred years ago. Low voter turnouts reflect a growing sense of frustration with the political system, while new technologies and ideas for reform offer intriguing possibilities for the future. As we enter the twenty‐first century, what better time is there to explore these and other issues?
A Civil Education for the Twenty‐First Century: Preparing Students for a Three‐Sector Society
Authors: Rifkin Jeremy 
Published: July 2004

AbstractNew economic and political realities require us to rethink the mission
of civic society in years to come. Thinking of society as creating three
types of capital—market, public, and social—opens up new possibilities for reconceptualizing the social contract and the kind of education
we give our young people.
Doing Democracy: An Exploration of Progressive‐Era Reform and Its Legacy for American Politics
Authors: Mattson Kevin 
Published: July 2004

AbstractThe social centers movement of the early twentieth century tried to show exactly what democratic politics could look like by opening public schools as places where adult citizens could educate themselves and one another about current political issues. At these evening “social centers,” citizens could learn about issues, deliberate with one another, and make decisions among possibilities for action.
Public Hospital Authorities for Public Purposes?
Authors: O'Looney John 
Published: June 2004

AbstractIt is estimated that there are more than seven thousand independent public authorities in the United States. What makes these quasi‐
governmental authorities unique is a blend of public powers with a more private‐sector‐like administrative style. By being able to avoid the formal rules that permeate most public bureaucracies, they can move more swiftly and decisively than government, but at the potential risk of special interests having substantially greater influence over public policy decisions than the public at large.
Creating a Healthy Democracy
Authors: Gates Christopher T. 
Published: June 2004

AbstractIt has never been more difficult for local governments to meet the challenges they face. The issues have grown increasingly complex. Angry citizens and cynical news media mock the political process and despair of finding solutions to community problems. The National Civic League, however, has come to recognize that issues do not stop communities—communities stop themselves. No challenge is too big or difficult when government, business, nonprofits, and citizens come together to work toward common goals. The Civic Index is a valuable tool for communities to use to evaluate where they stand within the new realities of citizen democracy and to determine their strengths and weaknesses.
Stages of the Process: Using the Civic Index
Authors: Okubo Derek , Weidman Karen , O'Connor Drew , Geha Nancy 
Published: June 2004

AbstractThe National Civic League provides a framework for optimal use of the Civic Index; however, the index can be adapted to fulfill the needs of specific communities, programs, and other entities. Each community must decide which approach is most appropriate to its particular needs. The Civic Index process typically has three stages: the initiating stage, the stakeholder stage, and the implementation stage. Understanding the stages of the process can help communities use the Civic Index to assess their own civic infrastructures.
Detection and false‐positive rates of maternal serum markers for Down syndrome screening according to maternal age in women over 35 years of age. A study of the agreement of eight dedicated software packages
Authors: Muller Françoise , Thalabard Jean‐Christophe , Ngo Sandrine , Dommergues Marc 
Published: June 2004

AbstractMaternal serum markers for trisomy 21 screening (MSS) can be assayed in women ≥35 years in an attempt to reduce the need for invasive procedures and thereby avoid their side effects. Our objective was to compare, in women ≥35, eight different software packages dedicated to second trimester MSS, thus providing reliable data for patient counselling. A simulation study was carried out on 189 sera from women with Down syndrome fetuses and 11 962 sera from mothers of unaffected babies. The first step was to estimate the joint distribution of alpha‐fetoprotein (AFP) and free beta‐human chorionic gonadotrophin (β‐hCG). The second step was to calculate trisomy 21 detection and false‐positive rates for each software according to maternal age (35–45 years), using the usual 1:250 risk threshold. Agreement between software packages was measured using 2×2 kappa coefficients. Detection rates and false‐positive rates increased with maternal age. Depending on the software, 57–71% detection rates were achieved at 35 years with 12–18% false‐positive rates. At 45 years, 61–100% detection rates were achieved with 66–95% false‐positive rates. Up to 39 years, all softwares were concordant (kappa coefficients >0.75). In the range 35–45 years, false‐positive and detection rates increased substantially with maternal age and differences between software packages are observed. Copyright © 2002 John Wiley & Sons, Ltd.
Interrupted aortic arch type A with 22q11 deletion: prenatal detection of an unusual association
Authors: Volpe P. , Gentile M. , Marasini M. 
Published: June 2004

AbstractInterrupted aortic arch is a rare, severe congenital heart defect subdivided into three types, A, B and C, according to the site of interruption. Type C is by far the least common form of interrupted aortic arch (less than 5% of cases), type A is commonly an isolated defect whereas type B is frequently associated with 22q11 deletion. Differentiation of interrupted aortic arch type A from type B by prenatal echocardiography is possible but difficult; it needs to be done on the basis of observation of reliable morphological indicators which point to the correct diagnosis. Here we report the first case of prenatal diagnosis of interrupted aortic arch type A associated with 22q11 deletion. The significance of this association is not yet clear, since 22q11 genes mainly affect embryonic cardiovascular morphogenesis of those regions whose development is critically dependent on neural crest cell migration and function, affected in type B defect but not in type A. Copyright © 2002 John Wiley & Sons, Ltd.
Factors affecting outcomes of prenatally‐diagnosed tumours
Authors: Chan K. L. , Tang M. H. Y. , Tse H. Y. , Tang R. Y. K. , W Lam H. S. , Lee C. P. , Tam P. K. H. 
Published: June 2004

AbstractObjectiveThe outcomes of prenatally‐diagnosed tumours affect obstetrical management and parental decisions. The present study reviews the factors affecting outcomes for fetuses with prenatally‐diagnosed tumours.MethodsMedical records of all fetuses referred to our institutions with antenatally‐diagnosed tumours were reviewed for the type and location of the tumours, results of treatment and/or causes of death.ResultsFrom January 1994 to May 2001, there were 15 fetuses with antenatally‐ diagnosed tumours: mesoblastic nephroma (MN) (n=2); neuroblastoma (NB) (n=2); cystic hygroma (CH) (n=3); intracranial germ cell tumour (IGCT) (n=2); sacrococcygeal teratoma (SCT) (n=3) and haemangioma (liver, n=2; limb, n=1). One mother had termination of pregnancy for her fetal SCT. Three mothers had Caesarean section for large fetal heads (CH, n=2; IGCT, n=1). Three fetuses died; two with IGCT and one with SCT, who died of heart failure. Two newborns with CH needed emergency intubation and, later, one of them had tracheostomy. One baby had cardiac failure resulting from a lower limb haemangioma and needed drug therapy. All solid tumours (MN, NB, SCT) of the live births had no recurrence after surgery with or without adjuvant chemotherapy.ConclusionPrenatally‐diagnosed tumours without any other associated abnormality cause morbidity and mortality because of their location and vascularity. Solid tumours are relatively benign. Copyright © 2002 John Wiley & Sons, Ltd.
Isolated sulfite oxidase deficiency: mutation analysis and DNA‐based prenatal diagnosis
Authors: Johnson J. L. , Rajagopalan K. V. , Renier W. O. , Van der Burgt I. , Ruitenbeek W. 
Published: June 2004

AbstractIsolated sulfite oxidase deficiency is an autosomal recessive, neurological disorder resulting from a defect in SUOX, the gene encoding the enzyme that catalyzes the terminal reaction in the sulfur amino acid degradation pathway. In its classical, severe form, sulfite oxidase deficiency leads to intractable seizures, severe and progressive brain pathology and death at an early age. We report here on clinical features and mutational analysis of the genetic defect in a newborn with sulfite oxidase deficiency. Cultured fibroblasts from this patient exhibited no detectable sulfite oxidase activity, and a unique four base pair deletion was present in the cDNA isolated from the same source. Identification of the same genetic defect in a heterozygous state in each of the parents and the monitoring of subsequent pregnancies in this family by DNA‐based prenatal diagnosis are also described. The deletion mutation was identified in a homozygous state in uncultured chorionic villus tissue from the second pregnancy that was subsequently terminated. In the third pregnancy, the presence of sulfite oxidase activity and identification of the mutation in a heterozygous state suggested that the fetus was not affected. This pregnancy resulted in the birth of a normal child. Copyright © 2002 John Wiley & Sons, Ltd.
Communication, acknowledgment, and the morality of cyberspace
Authors: Hyde Michael J. , Mitra Ananda 
Published: June 2004

AbstractThis essay deals with four related topics: ethics, the human face, computer communication, and the public sphere of cyberspace. Relating these topics allows us to explore the existential character of this “virtual” dwelling place (ethos). Much is made of how the “face work” that goes on in cyberspace defines an effort in rhetorical eloquence.
Datenspeicher im Fokus
Authors: Drach Volker 
Published: June 2004

AbstractDreidimensionale optische Datenspeicher versprechen hohe Speicherdichten. Voraussetzung für einen Einsatz in der Technik sind aber Zuverlässigkeit und Langzeitstabilität. Um diese Ziele zu erreichen, müssen geeignete physikalische Mechanismen für den Schreib‐ und Lesevorgang und passende Materialien gefunden werden. Forscher vom amerikanischen Boston College entdeckten jüngst ein viel versprechendes Polymer zur digitalen Datenspeicherung auf Basis von Mehrphotonenprozessen [1].
Diphenol miscibility effect on the immiscible polyester/polyether binary blends through intermolecular hydrogen‐bonding interaction
Authors: Hexig Bayar , He Yong , Asakawa Naoki , Inoue Yoshio 
Published: July 2004

AbstractMiscibility and hydrogen bonding interaction have been investigated for the binary blends of poly(butylene adipate‐co‐44 mol % butylene terephthalate)[P(BA‐co‐BT)] with 4,4'‐thiodiphenol (TDP) and poly(ethylene‐ oxide)(PEO) with TDP; and the ternary blends of P(BA‐co‐BT)/PEO/TDP by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The DSC results indicated that the binary blends of P(BA‐co‐BT)/TDP and PEO/TDP were miscible because each blend showed only one composition‐dependent glass‐transition over the entire range of the blend composition. The formation of intermolecular hydrogen bonds between the hydroxyl groups of TDP and the carbonyl groups of P(BA‐co‐BT), and between the hydroxyl groups of TDP and the ether groups of PEO was confirmed by the FTIR spectra. According to the glass‐transition temperature measured by DSC, P(BA‐co‐BT) and PEO, their binary blends were immiscible over the entire range of blend composition, however, the miscibility between P(BA‐co‐BT) and PEO was enhanced through the TDP‐mediated intermolecular hydrogen bonding interaction. It was concluded that TDP content of about 5–10% may possibily enhance miscibility between P(BA‐co‐BT) and PEO via a hydrogen bonding interaction. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2971–2982, 2004