bluuebunny/crossref_metadata_2025_split huggingface dataset:
Planar ultrawideband antenna with multiple band‐notches based on folded stepped‐impedance resonator and defected split ring resonator
Authors: Li Tong , Zhai Huiqing , Li Guihong , Li Long , Liang Changhong 
Published: January 2013

AbstractTo avoid potential inference problems due to the existing wireless communication systems within ultrawideband (UWB) operating frequency, a planar UWB antenna with triple band‐notches is proposed in this article. This antenna provides good rejection characteristic at 2.4/3.5/5.5 GHz bands by folded stepped‐impedance resonators (SIRs) coupled to the feed line, and defected split ring resonators below the folded SIRs. The stacked notch structure generates multiband notches but occupies only one area. Good agreement between the simulation and measurement is obtained, which shows that the proposed antenna achieves a wide bandwidth from 2 to 12 GHz with triple band‐notches successfully. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:600–603, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27364
UWB power divider with one narrow notch‐band and wide stop‐band
Authors: Chen Lei , Wei Feng , Jia Gao Chang , Qiang Liu Wei 
Published: January 2013

AbstractA compact ultrawideband (UWB) microstrip power divider (PD) with one sharply rejected notch‐band and wide stopband is analyzed and designed in this article.The proposed UWB PD is based on conventional Wilkinson PD, while interdigital hairpin resonators are introduced in two symmetrical output ports to widen passband. The stepped impedance resonator is studied and used to generate one desired notched band. Defected ground structure is introduced to improved stopband performance. Theoretical and simulated results are presented, which are in good agreement with the measured results. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:597–600, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27365
Optimization of slit structures for transmission enhancement of THz wave
Authors: Yuan Minghui , Huang Xin , Zhang Xuanfeng 
Published: January 2013

AbstractOptimal transmission characteristics of THz wave through a slit aperture with parallel grooves on both sides are analyzed numerically by the finite element method. Simulations results show that the center transmissivity can be up to above 95% because of the enhanced transmission effect induced by surface plasmon polaritons. With the increase of periodicity length p or center hole width d or groove depth s, the center frequency shifts red linearly, the center transmissivity increases firstly and then decreases. Furthermore, with the increase of d/p, w/p, or s/t, the center transmissivity increases firstly and then decreases, which the optimal values d/p= 0.25–0.3, w/p= 0.5, and s/t= 0.2. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:559–561, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27366
Considerations on the backscattered wireless communication links
Authors: Duroc Yvan , Vera Gianfranco Andia 
Published: January 2013

AbstractThis article presents a study of the backscattered wireless communication links, in far‐field conditions, emphasizing new approaches.General expressions for forward and return link on the reradiating coexistence of antennas are presented. A formulation for the radar cross section parameter is proposed for taking into account the phase information in modeling. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:554–559, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27367
Hexaferrite slant and slot MIMO antenna element for mobile devices
Authors: Abo Gavin S. , Hong Yang‐Ki , Syslo Ryan , Lee Jaejin , Lee Woncheol , Kwon Hyuck M. , Jayasooriya Chandana K. K. 
Published: January 2013

AbstractA hexaferrite slant and slot multiple‐input multiple‐output antenna with miniature antenna elements was simulated, fabricated, and characterized for antenna performance. Measured return loss and isolation were −33.9/−26.6 dB (for antenna 1/antenna 2) and −18.6 dB at 2.45 GHz, respectively. Measured bandwidth was 454/502 MHz at VSWR < 3. Correlation coefficient between antenna elements calculated from experimental S‐parameters was less than 0.00085 between 2.4 and 2.5 GHz. Radiation efficiency of the antennas was measured to be 82% at 2.45 GHz. The antennas have two lobes, omnidirectional, and flower patterns for potential mobile device applications. Simulated and measured antenna performance was found to be in good agreement with each other. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:551–554, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27370
Dual notched U—Slots triple band tunable rectangular microstrip antenna
Authors: Kulkarni Nagraj , Mulgi S. N. , Satnoor S. K. 
Published: January 2013

AbstractThis article presents a novel design and development of dual‐notched U slots rectangular microstrip antenna for quad band tunable operation. The antenna operates between 3.45 and 8.75 GHz at four different frequency bands. The middle two bands merge into a single band by changing the width of U slot on the patch. This change will also effect in tuning the three bands on either side of the frequency spectrum without changing the nature of linearly polarized broadside radiation characteristics. The proposed antenna gives a peak gain of 1.52 dB. The experimental and simulated results are in good agreement with each other. A design concept of the antenna is given and experimental results are presented and discussed. This antenna may find applications in WLAN, WiMax, and the fourth generation mobile communication systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:509–513, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27372
Compact parallel‐coupled line bandpass filter using double complementary split ring resonators
Authors: Ahn Chi‐Hyung , Jung Dong‐Jin , Chang Kai 
Published: January 2013

AbstractA novel compact parallel‐coupled line bandpass filter (BPF) with complementary split ring resonators (CSRRs) is presented in this letter.The proposed BPF, with a combination of CSRRs and parallel‐coupled lines, has the advantages of compact size and simpler design procedure compared with conventional CRSS BPFs. The prototype filter achieves the measured insertion loss of 1.4 dB at 3.6 GHz. The implementing area is 0.35 λg × 0.14 λg, where λg is the guided wavelength at the resonant frequency. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:506–509, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27373
AN ENG ZOR unit cell antenna using spiral inductors with enhanced bandwidth
Authors: Kim Jeongpyo , Yang Dooyeong 
Published: January 2013

AbstractIn this article, the characteristics of an epsilon negative zeroth‐order resonator (ENG ZOR) unit cell antenna are studied. The proposed ENG ZOR unit cell consists of two shunt inductors with a spiral inductor and a vertical post for epsilon negative property and a bent patch between two inductors for right‐handed property. The shunt inductors of the ENG ZOR unit cell are fabricated by using square spiral inductors and vertical posts. The impedance bandwidth and radiation efficiency of the designed ENG ZOR unit cell antenna are compared by adjusting dimensions of spiral inductors and fixing the patch between two spiral inductors. Under the constant resonant frequency, the bandwidth of the ENG ZOR antenna is proportional to the parasitic resistance of the spiral inductor without decreasing of the radiation efficiency. Therefore, the bandwidth of the ENG ZOR with a spiral inductor can be widened by narrowing the line width of the spiral inductor. Details of the antenna characteristics are described, and both simulated and measured results of the designed antenna are presented. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:567–571, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27382
An inverse problem for dielectrics that depend on two spatial variables
Authors: Hooshyar M. A. , Paudel Ajaya 
Published: January 2013

AbstractThe inversion method developed by Reese T. Prosser for waves in three dimensions is modified to solve inverse problems of back scattered data for TM plane waves incident on cylindrical structures with dielectric properties that are function of two spatial variables. Not only the bounds needed for convergence proof of the modified method are found but also the method is numerically implemented and its numerical performance examined. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:561–566, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27383
Two antipodal vivaldi antennas and an antenna array for microwave early breast cancer detection
Authors: Shao Wenyi , Adams Ryan S. 
Published: January 2013

AbstractTwo small antipodal Vivaldi antennas for ultrawide band early breast cancer detection are proposed. The antennas are designed to operate in the spectrum from 1 to 10 GHz, according to the requirements of wave penetration in the breast and imaging resolution. Simulated and measured reflection parameters of the proposed antennas are evaluated. Numerical results also show the proposed antennas have good near‐field radiation performance. Finally, an antenna array consisting of eight antipodal Vivaldi antennas, appropriate to collect the tumor scattering signal in the breast is presented. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:670–674, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27384
The use of lattice networks for modelling symmetric transmission line components and discontinuities
Authors: Abdo‐Sánchez Elena , Esteban Jaime , Martín‐Guerrero Teresa M. , Page Juan E. , Camacho‐Peñalosa Carlos 
Published: January 2013

AbstractThis article proposes the lattice network as a beneficial alternative to T‐ and
$ \Pi - $topologies for modeling symmetric transmission line discontinuities and components.The lattice network presents some important features, which make it a powerful tool to find realizable equivalent circuits. The limitations of the T‐ and
$ \Pi - $topologies and the validity of the lattice network in terms of realizability are highlighted in this article through two microstrip components: a dumbbell‐shaped defected ground structure and a microstrip stepped‐impedance hairpin resonator. Moreover, the lattice image impedance is proposed here as a parameter that allows determining whether a branch of the network is predominant. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:636–639, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27385
Novel 2:1 Wilkinson power divider integrated with bandpass filter
Authors: Gao Li , Yin Zhang Xiu 
Published: January 2013

AbstractA novel 2:1 Wilkinson power divider integrated with two bandpass filters is presented in this article.The proposed device exhibits the unequal power splitting function with a bandpass response. The phase and impedance characteristics of the bandpass filters can be conveniently tuned to realize impedance transformation. Thus they can replace the quarter‐wavelength transmission lines of the unequal Wilkinson power divider. The integrated device results in lower insertion loss and smaller circuit area, as compared with the cascaded connection of an unequal power divider and two filters. For demonstration, a 2:1 power divider integrated with bandpass filters is implemented. Comparisons of the measured and simulated results are presented to verify the proposed design. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:646–648, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27395
Characteristics of optical fiber refractive index sensor based on surface plasmon resonance
Authors: Lin Yu‐Cheng 
Published: January 2013

AbstractA refractive index optical fiber sensor based on surface plasmon resonance technology is demonstrated. The sensing device is a multimode optical fiber in which half of the core is polished away and a thin‐film layer of gold is deposited. We measure the spectrum‐difference variations and the resonance wavelength shifts for different refractive index solutions. In terms of the experimental data, the characteristics including resolution, sensitivity, and signal‐to‐noise ratio for the sensor are obtained. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:574–576, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27397
Lung morphometry using hyperpolarized 129Xe apparent diffusion coefficient anisotropy in chronic obstructive pulmonary disease
Authors: Ouriadov Alexei , Farag Adam , Kirby Miranda , McCormack David G. , Parraga Grace , Santyr Giles E. 
Published: January 2013

PurposeThe goal of this work was to investigate lung morphological changes associated with chronic obstructive pulmonary disease (COPD) using hyperpolarized 129Xe diffusion‐weighted MRI.MethodsHyperpolarized 129Xe MRI was performed at three different nonzero diffusion sensitizations (b‐value = 12, 20, and 30 s/cm2) in the lungs of four subjects with COPD and four healthy volunteers. The image signal intensities were fit as a function of b‐value to obtain anisotropic diffusion coefficient maps for all subjects. The image signal intensities were also fit to a morphological model allowing extraction of length scales associated with the terminal airways: external radius (R), internal radius (r), mean airspace chord length (Lm), and depth of alveolar sleeve (h).ResultsLongitudinal (DL) and transverse (DT) anisotropic diffusion coefficients were both significantly increased (both P= 0.004) in the COPD subjects (0.102 ± 0.02 cm2/s and 0.072 ± 0.02 cm2/s, respectively) compared with the healthy subjects (0.083 ± 0.011 cm2/s and 0.046 ± 0.017 cm2/s, respectively). Significant morphological differences were observed between the COPD subjects and healthy volunteers, specifically decreases in h (68 ± 36 µm vs. 95 ± 710 µm, respectively, P = 0.019) and increases in Lm (352 ± 57 µm vs. 253 ± 37 µm, respectively, P = 0.002) consistent with values obtained previously using hyperpolarized 3He MRI in similar subjects.ConclusionsDiffusion‐weighted hyperpolarized 129Xe MRI is a promising technique for mapping changes in human lung morphology and may be useful for early detection of emphysema associated with COPD. Magn Reson Med 70:1699–1706, 2013. © 2013 Wiley Periodicals, Inc.
Association between anti‐TNF‐α therapy and interstitial lung disease
Authors: Herrinton Lisa J. , Harrold Leslie R. , Liu Liyan , Raebel Marsha A. , Taharka Ananse' , Winthrop Kevin L. , Solomon Daniel H. , Curtis Jeffrey R. , Lewis James D. , Saag Kenneth G. 
Published: January 2013

ABSTRACTBackgroundAnti‐tumor necrosis factor‐α (TNF‐α) agents have been hypothesized to increase the risk of interstitial lung disease (ILD), including its most severe manifestation, pulmonary fibrosis.MethodsWe conducted a cohort study among autoimmune disease patients who were members of Kaiser Permanente Northern California, 1998–2007. We obtained therapies from pharmacy data and diagnoses of ILD from review of X‐ray and computed tomography reports. We compared new users of anti‐TNF‐α agents to new users of non‐biologic therapies using Cox proportional hazards analysis to adjust for baseline propensity scores and time‐varying use of glucocorticoids. We also made head‐to‐head comparisons between anti‐TNF‐α agents.ResultsAmong the 8417 persons included in the analysis, 38 (0.4%) received a diagnostic code for ILD by the end of follow‐up, including 23 of 4200 (0.5%) who used anti‐TNF‐α during study follow‐up, and 15 of 5423 (0.3%) who used only non‐biologic therapies. The age‐standardized and gender‐standardized incidence rate of ILD, per 100 person‐years, was 0.21 [95% confidence interval (CI) 0–0.43] for rheumatoid arthritis and appreciably lower for other autoimmune diseases. Compared with the use of non‐biologic therapies, use of anti‐TNF‐α therapy was not associated with a diagnosis of ILD among patients with rheumatoid arthritis (adjusted hazard ratio, 1.03; 95%CI 0.51–2.07), nor did head‐to‐head comparisons across anti‐TNF‐α agents suggest important differences in risk, although the number of cases available for analysis was limited.ConclusionThe study provides evidence that compared with non‐biologic therapies, anti‐TNF‐α therapy does not increase the occurrence of ILD among patients with autoimmune diseases and informs research design of future safety studies of ILD. Copyright © 2013 John Wiley & Sons, Ltd.
Safe lists for medications in pregnancy: inadequate evidence base and inconsistent guidance from Web‐based information, 2011
Authors: Peters Stacey L. , Lind Jennifer N. , Humphrey Jasmine R. , Friedman Jan M. , Honein Margaret A. , Tassinari Melissa S. , Moore Cynthia A. , Mathis Lisa L. , Broussard Cheryl S. 
Published: January 2013

ABSTRACTPurposeMedication use during pregnancy is common and increasing. Women are also increasingly getting healthcare information from sources other than their physicians.MethodsThis report summarizes an environmental scan that identified 25 active Internet sites that list medications reported to be safe for use in pregnancy and highlights the inadequate evidence base and inconsistent guidance provided by these sites.ResultsThese lists included 245 different products, of which 103 unique components had been previously evaluated in terms of fetal risk by the Teratogen Information System (TERIS), a resource that assesses risk of birth defects after exposure under usual conditions by consensus of clinical teratology experts. For 43 (42%) of the 103 components that were listed as ‘safe’ on one or more of the Internet sites surveyed, the TERIS experts were unable to determine the fetal risk based on published scientific literature. For 40 (93%) of these 43, either no data were available to assess human fetal risk or the available data were limited.ConclusionsWomen who see a medication on one of these ‘safe’ lists would be led to believe that there is no increased risk of birth defects resulting from exposure. Thus, women are being reassured that fetal exposure to these medications is safe even though a sufficient evidence base to determine the relative safety or risk does not exist. Copyright © 2013 John Wiley & Sons, Ltd.
Fast GaN based Schottky diodes on Si(111) substrate with low onset voltage and strong reverse blocking
Authors: Treidel Eldad Bahat , Hilt Oliver , Wentzel Andreas , Würfl Joachim , Tränkle Günther 
Published: January 2013

AbstractGaN‐based heterostructure lateral Schottky barrier diodes (SBD) grown on Si(111) substrate are presented in this work. These SBDs own very low onset‐voltage, VF = 0.50 V, high reverse blocking VBR > 600 V for LAC > 8 µm, very low capacitive charge of 0.415 nC/A and a very fast recovery time of 6 ps extracted under large signal operation conditions. These unique qualities are achieved by combining lateral topology, AlGaN back‐barrier epitaxial structure, fully recessed Schottky anode (ϕB = 0.62 eV) and anode field plate extension (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron‐beam incident‐angle‐ resolved cathodoluminescence studies on bulk ZnO crystals
Authors: Onuma Takeyoshi , Yamaguchi Tomohiro , Honda Tohru 
Published: January 2013

AbstractElectron‐beam incidence‐angle‐resolved cathodoluminescence (IAR‐CL) measurements on ZnO single crystals were demonstrated as an alternative way for the depth‐resolved cathodoluminescence (CL) study by scanning acceleration voltage of the electron‐beam. Incidence‐angle dependent near‐band‐edge CL intensities were well reproduced by analyses considering a radiation pattern, an expansion of the electron‐beam irradiation area, and an internal absorption factors. The quantitative agreement between the experimental and simulated results indicates that the IAR‐CL technique is suitable for practical use in the depth‐resolved CL study of device structures (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The impact of cloud‐affected IR radiances on forecast accuracy of a limited‐area NWP model
Authors: Stengel M. , Lindskog M. , Undén P. , Gustafsson N. 
Published: January 2013

AbstractThe impact of cloud‐affected satellite radiances on numerical weather prediction (NWP) accuracy is investigated. The NWP model used is the HIgh Resolution Limited Area Model (HIRLAM). Its four‐dimensional variational data assimilation (4D‐Var) system was used to assimilate cloud‐affected infrared (IR) radiances from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI). Cloud parameters are modelled internally in the observation operator and used in the radiative transfer calculations. The interaction between the cloud parameters and the model control vector variables is incorporated in the adjoint version of the observation operator, which is used to derive cloud‐affected Jacobians prior to the inner‐loop minimization of the cost function.The developed framework supports an extensive usage of satellite observations with spatial coverage extended into cloudy regions, which therefore provides additional analysis increments and supports a more accurate description of the atmospheric state. In extended assimilation and forecast experiments the total number of assimilated satellite observations could be increased by approximately 10%. This was associated with a clear indication of a positive impact of cloud‐affected radiances on the moisture and geopotential height ﬁelds of the NWP model analysis and forecast accuracy when used on top of clear‐sky radiance observations. This is revealed by reduced analysis errors of the total integrated water vapour and by reduced forecast errors in the mid and upper troposphere.
Comment on “Statistical physics of a mesoscopic fermion system inside a rectangular box” by Radu Lungu
Authors: Toutounji Mohamad 
Published: January 2013

AbstractThis comment is to overemphasize that the mathematical treatment, calculations, discussions, and concluding remarks in the article by Toutounji[1] are limited to one‐particle system only; this is to the contrary of what the author in Lungu[2] tried to seize on. © 2012 Wiley Periodicals, Inc.
Twin anemia–polycythemia sequence in a case of monoamniotic twins
Authors: Diehl W. , Glosemeyer P. , Tavares De Sousa M. , Hollwitz B. , Ortmeyer G. , Hecher K. 
Published: January 2013

ABSTRACTTwin anemia–polycythemia sequence (TAPS) complicates up to 6% of monochorionic diamniotic twin pregnancies, typically in the late second or third trimester. The presence of only a few and very small arteriovenous vascular anastomoses characterizes the underlying angioarchitecture at the chorionic plate in cases of TAPS. In monoamniotic twins, large vascular anastomoses can usually be seen at the placental vascular equator, and therefore one would not expect the development of TAPS in monoamniotic twins. We report a case of TAPS in a monoamniotic pregnancy at 26 + 5 weeks' gestation which responded favorably to fetoscopic laser coagulation of the small placental anastomoses, resolving severe anemia in one twin and polycythemia in the other. The pregnancy continued until 32 + 5 weeks, when worsening cord entanglement with increased resistance and the development of postsystolic notches in the umbilical artery of one twin prompted delivery by Cesarean section. There was only a moderate difference in neonatal hemoglobin concentrations, with the former polycythemic twin needing a single partial volume exchange transfusion. The postnatal course of the neonates was uneventful, according to their gestational age at birth. To our knowledge this is the first case report describing successful laser therapy for TAPS in monoamniotic twins. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.