bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electronic structure of Prx La1‐xAlO3 solid solution
Authors: Szubka M. , Talik E. , Molak A. , Turczyński S. , Pawlak D. A. 
Published: October 2010

AbstractThe crystals of Prx La1−xAlO3 solid solution grown by the Czochralski method were examined by X‐ray photoelectron spectroscopy. The electric conductivity was measured at high temperature range. The composition of the Prx La1−xAlO3+xcrystals obtained with XPS analysis exhibited an increased content of oxygen in comparison to the nominal value. The praseodymium valence may influence the coloration of the Prx La1−xAlO3 crystals. In the dark brown colour Pr0.40La0.60AlO3 sample with the highest amount of oxygen the 3d4f1 satellite lines have the highest intensity and were attributed to presence of Pr4+ ions. The semiconducting properties of the Prx La1−xAlO3 single crystals correspond to the electronic structure determined with the XPS measurements and to the deduced occurrence of defects. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Single crystal growth and structural properties of iron telluride doped with nickel
Authors: Zajdel P. , Zubko M. , Kusz J. , Green M. A. 
Published: October 2010

AbstractWe report the single crystal growth of Fe1.1−xNix Te with nominal compositions x = 0.01, 0.025, 0.05 and 0.1 using a slow cooled melt technique. Cylindrical crystals 0.5 cm in diameter and 2 cm long were obtained. The initial characterization, done using single‐crystal diffractometer, revealed that the lattice parameter a increases and c decreases with Ni content. The crystal structure refinement was performed in the P4/nmm space group. Chemical analysis confirmed the presence of nickel in the system close to the nominal content. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Micropower high current‐drive class AB CMOS current‐feedback operational amplifier
Authors: Lopez‐Martin Antonio J. , Ramirez‐Angulo Jaime , Carvajal Ramón G. , Acosta Lucía 
Published: October 2010

AbstractA novel CMOS current‐feedback operational amplifier (CFOA) aimed to low‐power applications is proposed. The use of a compact class AB implementation allows high current‐drive capability and simultaneously very low quiescent power consumption. Measurement results of a fabricated prototype show for an inverting configuration a closed‐loop bandwidth of 1 MHz independent of gain setting, and a slew rate of 2V/µs for a load capacitance of 30 pF and a quiescent power consumption of 264µW. Copyright © 2010 John Wiley & Sons, Ltd.
A CMOS voltage regulator for passive RFID tag ICs
Authors: Guo Jianping , Leung Ka Nang 
Published: October 2010

SUMMARYA low‐power voltage regulator for passive RFID tag ICs is proposed in this paper. It consists of a self‐biased mutually compensated voltage reference, a low dropout (LDO) voltage regulation circuit and a power‐on‐reset (POR) circuit. It is fabricated in a commercial 0.18−µm CMOS technology and applied to a passive UHF RFID tag IC. The total quiescent current is 700 nA under a 1.8‐V supply. The output voltage of the regulator is 1.45 V with load capability of 50 µA. The temperature coefficients of the voltage reference and the output voltage are only 9 and 43 ppm/∘C, respectively. A POR signal with width pulse of 150 ns is generated for the digital part in the tag IC. Copyright © 2010 John Wiley & Sons, Ltd.
Robust model order reduction technique for MIMO systems via ANN‐LMI‐based state residualization
Authors: Alsmadi Othman M. K. , Abo‐Hammour Zaer. S. , Al‐Smadi Adnan M. 
Published: October 2010

SUMMARYEven though model order reduction (MOR) techniques for linear dynamical systems are developed rather properly, there are still quite a lot of issues to be considered. This paper addresses a novel MOR technique for multi‐input multi‐output system with dominant eigenvalue preservation, which leads to controller cost minimization. The new technique is formulated based on an artificial neural network (ANN) prediction of an upper triangular form of the system state matrix A. Using the new system state matrix along with the linear matrix inequality (LMI) optimization method, a permutation matrix is obtained which leads to the new formulation of the complete system considered for MOR. Utilizing the non‐projection state residualization technique, a reduced model order is obtained. The proposed ANN‐LMI‐based MOR method is compared with well‐known reduction techniques such as the balanced Schur decomposition, proper orthogonal decomposition (POD), and state elimination through balanced realization. Copyright © 2010 John Wiley & Sons, Ltd.
Phase noise characterization of subharmonic injection locked oscillators
Authors: Plessas Fotis , Tsitouras Athanasios , Kalivas Grigorios 
Published: October 2010

AbstractIn this work we present a detailed study of the phase noise of subharmonic injection locked oscillators (s‐ILOs). A new simple and efficient model has been presented for accurately predicting the phase noise of a microwave s‐ILO. The validity of the analytical technique is verified with measurement results obtained from a 5‐GHz fully differential Colpitts‐based s‐ILO. The results showed that a phase noise improvement of 12 dB at 1 kHz offset frequency compared to the free‐running case can be achieved, whereas the power consumption is 21 mW. Copyright © 2010 John Wiley & Sons, Ltd.
A study design with conditional, serially assessed co‐primary endpoints: An application to a single‐arm, pilot non‐Hodgkin's lymphoma trial
Authors: Mahnken Jonathan D. , Wick Jo A. , Gajewski Byron J. , Mayo Matthew S. 
Published: October 2010

AbstractOptimizing study designs is an important responsibility for applied statisticians supporting clinical trials. We describe the study design for an early‐phase non‐Hodgkin's lymphoma trial with two co‐primary endpoints; however, evaluation of the second endpoint on a subject is conditional on a positive response to the first endpoint. Thus, these dichotomous measures are collected conditionally and in series. We present the probability density function for this study design selected and derive the parameters that describe this distribution. We also derive the maximum likelihood estimates for the unknown parameters of interest to the trial investigator. We compare the theoretical operating characteristics (type I and type II error rates) to a simulation study for the motivating example. Using this report as a guide, others designing studies with similarly measured co‐primary endpoints can utilize these formulas to calculate the operating characteristics and analyze their resulting study data. Drug Dev Res 71: 395–403, 2010.  © 2010 Wiley‐Liss, Inc.
Synthesis and evaluation as PDE4 inhibitors of pyrimidine‐2,4‐dione derivatives
Authors: Giovannoni Maria P. , Graziano Alessia , Matucci Rosanna , Nesi Marta , Cesari Nicoletta , Vergelli Claudia , Biancalani Claudio , Crocetti Letizia , Cilibrizzi Agostino , Dal Piaz Vittorio 
Published: October 2010

AbstractA series of nitraquazone analogs with a pyrimidindione core was synthesized and tested for inhibitory activity on PDE4, selectivity versus PDE3 and PDE5 and for affinity towards the rolipram high‐affinity binding site (HARBS). The 5‐anilino derivatives 13–18 showed the best profile combining appreciable PDE4 inhibitory activity (IC50= 5–14 µM) with a good selectivity toward PDE3 and PDE5. The same compounds demonstrate low affinity for the HARBS site with IC50values of 12–69 µM (IC50for Rolipram = 3.6 nM). Drug Dev Res 72: 274–288, 2011. © 2010 Wiley‐Liss, Inc.
Dynamics of wetland vegetation under multiple stresses: a case study of changes in sawgrass trait, structure, and productivity under coupled plant‐soil‐ microbe dynamics
Authors: Muneepeerakul Chitsomanus P. , Muneepeerakul Rachata , Miralles‐Wilhelm Fernando , Rinaldo Andrea , Rodriguez‐Iturbe Ignacio 
Published: October 2010

AbstractThis paper quantifies wetland vegetation dynamics under drought, waterlogging, shading, and nutrient stresses within the coupled plant‐soil‐microbe system. A plant is characterized by three independent traits, namely leaf nitrogen (N) content, specific leaf area (SLA), and allometric carbon (C) allocation to rhizome storage, while plant growth is modelled through a dynamic plant allocation scheme. The modelling of N focuses on the internal cycle in which the aerobic and anaerobic processes are determined by the dynamics of oxygen controlled by plants, microbial aerobic processes, and hydrologic dynamics. The dynamics of water levels and soil moisture are described by a simple hydrologic model with stochastic rainfall and are decoupled from the plant‐soil‐microbe dynamics. Using the model to investigate the dynamics of sawgrass, the results, which are consistent with field observations in the southern Everglades, indicate that SLA decreases with increasing anaerobic condition. The lower SLA maintains high stomatal opening, while at the same time prevents cavitational collapse when sawgrass lowers its root:shoot ratio to reduce C cost in root anaerobic respiration. Given a naturally low but not too scarce level of phosphorus, net N mineralization is higher in the wetter hydrologic regimes because the increase in anaerobic decomposition and N mineralization compensate for the decline in those of aerobes; and the slower growing, more nitrogen efficient anaerobes compete less with plants for N. The optimal traits are the results of several counteracting trends of trade‐offs in C and N economy differently influenced by trait combinations in different wetland environments. Copyright © 2010 John Wiley & Sons, Ltd.
A New Building Block for Organometallic–Inorganic Hybrid Polymers: The Mixed Group 15/16 Element Ligand Complex [Cp*2Mo2(μ,η2:2‐PSe)2(μ‐Se)] (Cp* = C5Me5)
Authors: Bodensteiner Michael , Dušek Michal , Kubicki Marek M. , Pronold Michael , Scheer Manfred , Wachter Joachim , Zabel Manfred 
Published: October 2010

AbstractThe synthesis and spectroscopic characterization of [Cp*2Mo2P2Se3] (1; Cp* = C5Me5) and its use as a molecular building block in the formation of copper(I) halide polymers is described. The reaction of 1 in CH2Cl2 with 2 equiv. of CuBr and CuI in CH3CN under diffusion conditions gave [(Cp*2Mo2P2Se3)2(CuBr)2] (2) and [(Cp*2Mo2P2Se3)(CuX)3(CH3CN)]n (X = I; 3/4), respectively. The structure of 2 is distinguished by a central Cu2Br2 ring coordinated on each side by a tripledecker complex through one of its P atoms. A 2D network is formed by weak interactions between Se atoms of neighboring molecules. Compound [(Cp*2Mo2P2Se3)(CuI)3(CH3CN)]n exists in two isomeric forms 3 and 4. The crystal structure of 3 can be described as a two‐dimensional polymer that is formed by ribbons containing looped chains of three Cu2I2 rings and attached [Cp*2Mo2P2Se3] molecules. The structure of 4 contains a ribbon in which tripledecker molecules are linked through their P atoms to (CuI)6 clusters. The ribbons are connected by weak Se···Se interactions. The reaction of a mixture of 1 and P4Se3 with CuI gave [(Cp*2Mo2P2Se3)(P4Se3)(CuI)2]n. The crystal structure analysis of 5 reveals a new type of organometallic–inorganic framework in which 1 and P4Se3 are linked by Cu2I2 rings.
Zeo‐Click Chemistry: Copper(I)–Zeolite‐Catalyzed Cascade Reaction; One‐Pot Epoxide Ring‐Opening and Cycloaddition
Authors: Boningari Thirupathi , Olmos Andrea , Reddy Benjaram M. , Sommer Jean , Pale Patrick 
Published: October 2010

AbstractCopper(I)‐modified zeolites, especially CuI–USY, proved to be very efficient catalysts in multi‐component reactions of epoxides with sodium azide and terminal alkynes. Such catalysts allow highly regio‐ and stereoselective syntheses ofhydroxymethylated triazoles. These heterogeneous, modified zeolites can easily be recovered and reused. Moreover, the cascade reaction was best performed in water at room temperature, rendering all the processes truly green. Detailed investigations revealed the role the CuI‐modified zeolites play both during the epoxide ring‐opening and cycloaddition steps.
Fluoroalkylated α,β‐Unsaturated Imines: Efficient and Versatile Substrates for the Synthesis of Fluorinated Vinylogous β‐Amino Esters and 3,4‐Dihydropyridin‐2‐ones
Authors: Palacios Francisco , Ochoa de Retana Ana M. , Pascual Sergio , de Trocóniz Guillermo Fernández , Ezpeleta José M. 
Published: October 2010

AbstractA simple and efficient synthesis of vinylogous fluoroalkylated β‐amino mono‐ (4) and diester (9) derivatives by the regioselective 1,2‐addition of enolates derived from alkyl acetates or diethyl malonate to fluoroalkylated α,β‐unsaturated imines (1) is described. These fluorinated imines (1) were used as intermediates in the regioselective synthesis of fluorine‐containing trans‐3,4‐dihydropyridin‐2‐ones (6, 8a, 8b, 10) and 3,3‐spiro‐3,4‐dihydropyridin‐2‐ones (8c–h) by conjugate (1,4‐) addition of enolates derived from α‐mono‐ and α,α‐disubstituted esters. Fluoroalkylated β‐amino esters (4, 9) and 3,4‐dihydropyridin‐2‐ones (6, 8, 10) were also prepared by the olefination of enaminophosphonate 2 with BuLi, addition of aldehydes and subsequent addition of the enolates derived from esters 3.
Seismic response evaluation of an urban overpass
Authors: Mayoral Juan M. , Flores Francisco A. , Romo Miguel P. 
Published: October 2010

AbstractThe seismic response of one section of a 23 km strategic urban overpass to be built in the so‐called transition and hill zones in Mexico City is presented. The subsoil conditions at these zones typically consist on soft to stiff clay and medium to dense sand deposits, randomly interbedded by loose sand lenses, and underlain by rock formations that may outcrop in some areas. Several critical supports of this overpass are going to be instrumented with accelerometers, inclinometers and extensometers, tell tales and end pile cell pressures to assess their seismic performance during future earthquakes and to generate a database to calibrate soil–structure interaction numerical models. This paper presents the seismic performance evaluation of the critical supports located in one section of the overpass. Sets of finite elements models of the soil–foundation–structure systems were developed. Initially, the model was calibrated analyzing the seismic response that an instrumented bridge support exhibited during the June 15th, 1999 Tehuacan (Mw = 7) Earthquake. This bridge is located also within the surroundings of Mexico City, but in the lake zone, where highly compressible clays are found. The computed response was compared with the measured response in the free field, pile‐box foundation and bridge deck. Once the model prediction capabilities were established, the seismic response of the critical supports of the urban overpass was evaluated for the design earthquake in terms of transfer functions and displacement time histories. Copyright © 2010 John Wiley & Sons, Ltd.
Iterative implicit integration procedure for hybrid simulation of large nonlinear structures
Authors: Mosqueda G. , Ahmadizadeh M. 
Published: October 2010

AbstractA fully implicit iterative integration procedure is presented for local and geographically distributed hybrid simulation of the seismic response of complex structural systems with distributed nonlinear behavior. The purpose of this procedure is to seamlessly incorporate experimental elements in simulations using existing fully implicit integration algorithms designed for pure numerical simulations. The difficulties of implementing implicit integrators in a hybrid simulation are addressed at the element level by introducing a safe iteration strategy and using an efficient procedure for online estimation of the experimental tangent stiffness matrix. In order to avoid physical application of iterative displacements, the required experimental restoring force at each iteration is estimated from polynomial curve fitting of recent experimental measurements. The experimental tangent stiffness matrix is estimated by using readily available experimental measurements and by a classical diagonalization approach that reduces the number of unknowns in the matrix. Numerical and hybrid simulations are used to demonstrate that the proposed procedure provides an efficient method for implementation of fully implicit numerical integration in hybrid simulations of complex nonlinear structures. The hybrid simulations presented include distributed nonlinear behavior in both the numerical and experimental substructures. Copyright © 2010 John Wiley & Sons, Ltd.
Modelling the effect of time‐dependent river dune evolution on bed roughness and stage
Authors: Paarlberg Andries J. , Dohmen‐Janssen C. Marjolein , Hulscher Suzanne J. M. H. , Termes Paul , Schielen Ralph 
Published: October 2010

AbstractThis paper presents an approach to incorporate time‐dependent dune evolution in the determination of bed roughness coefficients applied in hydraulic models. Dune roughness is calculated by using the process‐based dune evolution model of Paarlberg et al. (2009) and the empirical dune roughness predictor of Van Rijn (1984). The approach is illustrated by applying it to a river of simple geometry in the 1‐D hydraulic model SOBEK for two different flood wave shapes. Calculated dune heights clearly show a dependency on rate of change in discharge with time: dunes grow to larger heights for a flood wave with a smaller rate of change. Bed roughness coefficients computed using the new approach can be up to 10% higher than roughness coefficients based on calibration, with the largest differences at low flows. As a result of this larger bed roughness, computed water depths can be up to 15% larger at low flow. The new approach helps to reduce uncertainties in bed roughness coefficients of flow models, especially for river systems with strong variations in discharge with time. Copyright © 2010 John Wiley & Sons, Ltd.
Automatic transition from simulation to one‐shot shape optimization with Navier‐Stokes equations
Authors: Özkaya Emre , Gauger Nicolas R. 
Published: October 2010

AbstractWe introduce the one‐shot method and its application to aerodynamic shape optimization, where the governing equations are the incompressible Reynolds‐Averaged Navier‐Stokes (RANS) equations in combination with the k – ω turbulence model. We constrain the one‐shot strategy to problems, where steady‐state solutions are achieved by fixed‐point iteration schemes. The one‐shot optimization strategy pursues optimality simultaneously with the goals of primal and adjoint feasibility. To exploit the domain specific experience and expertise invested in the simulation tools, we propose to extend them in an automated fashion by the use of automatic differentiation (AD) tools. First, they are automatically augmented with an adjoint solver to obtain (reduced) derivatives and then this sensitivity information is immediately used to determine optimization corrections (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Discrete concepts versus error analysis in PDE‐constrained optimization
Authors: Hinze Michael , Tröltzsch Fredi 
Published: October 2010

AbstractSolutions to optimization problems with pde constraints inherit special properties; the associated state solves the pde which in the optimization problem takes the role of a equality constraint, and this state together with the associated control solves an optimization problem, i.e. together with multipliers satisfies first and second order necessary optimality conditions. In this note we review the state of the art in designing discrete concepts for optimization problems with pde constraints with emphasis on structure conservation of solutions on the discrete level, and on error analysis for the discrete variables involved. As model problem for the state we consider an elliptic pde which is well understood from the analytical point of view. This allows to focus on structural aspects in discretization. We discuss the approaches First discretize, then optimize and First optimize, then discretize, and consider in detail two variants of the First discretize, then optimize approach, namely variational discretization, a discrete concept which avoids explicit discretization of the controls, and piecewise constant control approximations. We consider general constraints on the control, and also consider pointwise bounds on the state. We outline the basic ideas for providing optimal error analysis and complement our analytical findings with numerical examples which confirm our analytical results (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Algorithms for PDE‐constrained optimization
Authors: Herzog Roland , Kunisch Karl 
Published: October 2010

AbstractSome first and second order algorithmic approaches for the solution of PDE‐constrained optimization problems are reviewed. An optimal control problem for the stationary Navier‐Stokes system with pointwise control constraints serves as an illustrative example. Some issues in treating inequality constraints for the state variable and alternative objective functions are also discussed (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Adaptive finite element discretization in PDE‐based optimization
Authors: Rannacher Rolf , Vexler Boris 
Published: October 2010

AbstractThis article surveys recent developments in the adaptive numerical solution of optimal control problems governed by partial differential equations (PDE). By the Euler‐Lagrange formalism the optimization problem is reformulated as a saddle‐point problem (KKT system) that is discretized by a Galerkin finite element method (FEM). Following the Dual Weighted Residual (DWR) approach the accuracy of the approximation is controlled by residual‐based a posteriori error estimates. This opens the way toward systematic complexity reduction in the solution of PDE‐based optimal control problems occurring in science and engineering (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
POD‐Galerkin approximations in PDE‐constrained optimization
Authors: Sachs Ekkehard W. , Volkwein Stefan 
Published: October 2010

AbstractProper orthogonal decomposition (POD) is one of the most popular model reduction techniques for nonlinear partial differential equations. It is based on a Galerkin‐type approximation, where the POD basis functions contain information from a solution of the dynamical system at pre‐specified time instances, so‐called snapshots. POD models have been applied very successfully in the area of optimization with PDEs or feedback control laws. Nevertheless, various issues are still unclear and are currently under research, e.g. timely updates of the snapshot information and error analyses for the POD approximations (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
MODELLING REFERENCE EVAPOTRANSPIRATION USING FEED FORWARD BACKPROPAGATION ALGORITHM IN ARID REGIONS OF AFRICA
Authors: Wang Yu‐Min , Traore Seydou , Kerh Tienfuan , Leu Jan‐Mou 
Published: October 2010

ABSTRACTModelling of the evapotranspiration process is central for efficient management of agricultural water resources in arid regions. Reference evapotranspiration (ETo) computation with the recommended Penman–Monteith (PM) equation is limited in Burkina Faso due to the numerous meteorological data required. Recently, to solve the climatic data unavailability problem, an alternative reference model (RMBF) has been developed for Burkina Faso. In a new approach, this study explores in three production regions, Dori, Bogande and Fada N'Gourma, the potential of using the feed forward backpropagation (BP) neural network algorithm for estimating ETo from temperature data. Furthermore, four temperature‐based models including BP, RMBF, Hargreaves (HRG) and Blaney–Criddle (BCR) were employed and compared with the true PM. Based on the statistical evaluation, RMBF, HRG and BCR consistently overestimated the ETo and showed poor performance.Moreover, BP is superior to RMBF, HRG and BCR. Clearly, temperature‐based BP is more reliable than the other alternative methods for ETo modelling in Burkina Faso. It is found that both wind velocity and relative humidity improve BP accuracy when integrated into the network input. Relative humidity does not show as strong a correlation to ETo as wind. Wind was found as the key variable of ETo and is highly recommended to be in the BP model for these arid regions of Africa under study. Copyright © 2010 John Wiley & Sons, Ltd.