bluuebunny/crossref_metadata_2025_split huggingface dataset:
The conservation of iron objects in archaeological preservation – Application and further development of alkaline sulphite method for conservation of large quantities of iron finds
Authors: Schmutzler B. , Ebinger‐Rist N. 
Published: March 2008

AbstractThe usual damage on archaeological iron finds caused by corrosion are outlined in this paper. For a better understanding of these phenomena and the resulting consequences for iron conservation a short literature summary is given regarding actual corrosion models for archaeological iron finds. The desalination of chloride‐contaminated iron finds is the demand to be derived from this synopsis. Therefore, the desalination with the alkaline sulphite reduction method is applied at Landesamt für Denkmalpflege Baden‐Württemberg recently, which allows the long‐term stabilization of many iron finds. Finally, the research project ‘Investigations into the alkaline sulphite treatment for conservation of large quantities of archaeological iron objects’ is introduced.
Transparente Beschichtungsstoffe zum Schutz von Kulturgütern Use of transparent coating systems for the protection of culture heritage
Authors: Conrads M. 
Published: March 2008

AbstractZusammenfassung: Der Schutz von technischen Kulturgütern macht den Einsatz transparenter Beschichtungsstoffe erforderlich um beispielsweise sog. Gebrauchsspuren und die damit verbundene Darstellung der Nutzung von Objekten zu erhalten.Die Dauerhaftigkeit transparenter Beschichtungsstoffe ist deutlich geringer als mit pigmentierten Systemen.Dieser Beitrag beschäftigt sich mit ersten Versuchen, die Unterschiede von verschiedenen transparenten Systemen wie Lacke, Wachse, Fette und Öle im Hinblick auf ihre Schutzwirkung zu ermitteln und aufzuzeigen.Die besten Ergebnisse zeigten bisher die Polyurethanlacke sowie die Ormocere.Summary: The protection of technical cultural heritage needs transparent coating systems to demonstrate e.g. marks of use and the herewith connected demonstration of the use of objects.The period of protection from transparent coating systems is much more shorter than with pigmented coloured paints.This article informs about first trials with different transparent coating systems like paints, waxes, fats and oils and shows the differences in their suitability for corrosion protection.The best results up to now show the polyurethane systems and the Ormoceres.
Poly(amide‐imides): Wire Enamels with Excellent Thermal and Chemical Properties
Authors: Murray Thomas J. 
Published: March 2008

AbstractPoly(amide‐imide) resins are versatile high‐performance polymers used as primary electrical insulation. They can be synthesized by three well‐established methods, of which only two are commercially exploited. Outstanding characteristics include high thermal performance, chemical and abrasion resistance, and low coefficient of friction. Other industries also rely on these same properties for use as coatings, extrusion resins and films. Recent developments are discussed and future trends/product offerings are reviewed. Developments include corona‐resistant enamels, self‐lubricated and high‐abrasion‐resistance coatings. The hybrid automobile industry offers opportunities for further innovations in primary electrical coatings.magnified image
Polymer Crystallization: A DSC Approach to Building the T‐CR‐T Diagram
Authors: Berlanga Rosa , Suñol Joan J. , Saurina Joan 
Published: March 2008

AbstractT‐CR‐T diagrams are one of the most reliable ways to predict the thermal behavior of material solidification from the melt. A brief description of solidification accounting for continuous cooling is presented for fast‐crystallizing polymers. An isoconversional method is applied to the kinetic analysis of non‐isothermal processes. The solidification process of different polymer materials: high density polyethylene based samples and mixtures of PEG with a pharmaceutical drug were analyzed by means of DSC. Several diagrams were constructed and the best agreement between experimental data and the calculated T‐CR‐T curves corresponds to the use of the isoconversional method.magnified image
Alternative approach for modeling material interfaces in FDTD
Authors: Laakso Ilkka , Uusitupa Tero 
Published: March 2008

AbstractA simple alternative way to position dielectric materials in the finite‐difference time‐domain (FDTD) Yee cell grid is proposed. Plane‐wave illuminated spheres are used as examples to study the performance of the alternative method compared to the standard FDTD method. Although the performances are generally equally good, the alternative method may sometimes give significantly improved accuracy. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1211–1214, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23309
PMD mitigation and wavelength conversion using a SOA‐based interferometric switch
Authors: Jianping Wang 
Published: March 2008

AbstractWe propose a new application of the SOA‐based wavelength conversion, which can realize polarization mode dispersion (PMD) mitigation for 10 GHz picosecond optical pulse. Both PMD mitigation and wavelength conversion are demonstrated by experiments. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1171–1173, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23312
Velocity compensated coplanar wave guide bend for odd‐mode suppression
Authors: Hong Wang Jun , Zhang Hui 
Published: March 2008

AbstractA kind of velocity compensated coplanar wave guide (CPW) bend is proposed, in which one slot of CPW bend with shorter length is corrugated, so that the signal propagating in this slot is slowed down, and the signal propagating in the longer slot can catch up with the signal in the shorter slot. Both simulated and experimental results show that the odd mode can be suppressed efficiently by this kind of CPW bend, and the properties of reflection and transmission are improved significantly, especially in high‐frequency band. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1201–1204, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23315
Adaptive neuro‐fuzzy models for the quasi‐static analysis of microstrip line
Authors: Yildiz Celal , Guney Kerim , Turkmen Mustafa , Kaya Sabri 
Published: March 2008

AbstractThis article presents a new method based on adaptive neuro‐fuzzy inference system (ANFIS) to calculate the effective permittivities and characteristic impedances of microstrip lines. The ANFIS is a fuzzy inference system (FIS) implemented in the framework of an adaptive fuzzy neural network. It has the advantages of expert knowledge of FISs and learning capability of artificial neural networks. A hybrid learning algorithm, which combines the least square method and the back propagation algorithm, is used to identify the parameters of ANFIS. The results of ANFIS are compared with the results of the experimental works, quasi‐static methods, and a commercial electromagnetic simulator IE3D. There is very good agreement among the results of ANFIS models and quasi‐static methods, IE3D, and experimental works. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1191–1196, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23322
On‐chip slot antennas in 0.18 μm CMOS for wireless application
Authors: Jiang Liang , Yin Wen‐Yan , Mao Junfa 
Published: March 2008

AbstractTwo on‐chip slot antennas resonating near 30 GHz with different widths (10 and 100 μm) in standard 0.18 μm CMOS are presented. S21 between two 10 μm width slot antennas and between two 100 μm width ones both with ∼3 mm distance through free space is measured. The results indicate that designing on‐chip slot antennas with standard CMOS process is feasible, which will support farther improvement of CMOS integration. The slot antennas can be used in compact and low cost transceivers for short range wireless communications. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1187–1191, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23325
Narrow‐slot bandpass filter based on folded substrate‐integrated waveguide with wide out‐of‐band rejection
Authors: Lei Wang , Che Wenquan , Deng Kuan , Dong Shiwei 
Published: March 2008

AbstractThe folded substrate‐integrated waveguide (FSIW) takes the advantages of more compact size and higher integration than the conventional SIW structures, probably resulting in a very compact design. One simple narrow‐slot bandpass filter is thus proposed and implemented to demonstrate the superiority of FSIW structure. The design strategies of the bandpass filter are introduced. One prototype with three narrow slots in the middle layer of FSIW is fabricated to demonstrate the validity of the proposed design. For the sake of measurement, one back‐to‐back stripline transition is also designed. The measured results are in good agreement with the HFSS‐simulated results, which indicates that the bandwidth is about 15%; the insertion loss is less than 1.5 dB. In addition, the rejection band of this filter is quite wide, implying very good harmonic rejection. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1155–1159, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23327
Directly modulated laser diode in the nonlinear regime for low‐cost digital frequency up‐conversion
Authors: Constant S. B. , Guennec Y. Le , Maury G. , Lourdiane M. , Cabon B. 
Published: March 2008

AbstractThe purpose of this article is to demonstrate the extension of the modulation bandwidth of single mode laser sources to reach the RF frequency range of wireless access networks such as ultra‐wide band systems with low‐cost solutions. In this article, we have studied optical microwave mixing using nonlinear direct modulation of a distributed feedback (DFB) laser diode. First, the nonlinear behavior of the DFB laser diode near the threshold current has been analyzed and explained based on frequency mixing measurements made with CW signals. Then, we have experimentally demonstrated frequency up‐conversion of a QPSK signal. These results were compared to eye‐diagram simulations based on the laser static and dynamic characteristics. Subsequently, the frequency up‐conversion of a WLAN IEEE 802.11a signal was experimentally demonstrated. Best conditions in terms of DFB bias current and RF input power signals have been studied. Good conversion loss and EVM results have been obtained. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1214–1219, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23329
Observation and explanation of bending characteristics in solid core photonic crystal fibers
Authors: Ji Minning , Shi Zhidong , Lin Jianqiang 
Published: March 2008

AbstractBending loss peak is observed in the transmission spectrum of a solid core photonic crystal fiber. The loss peak is shifted from shorter wavelength to longer wavelength when the bending radius is decreased. These results are explained by a numerical calculation. They agree well with each other. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1178–1180, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23331
Internal wideband monopole antenna for MIMO access‐point applications in the WLAN/WIMAX bands
Authors: Chou Jui‐Hung , Su Saou‐Wen 
Published: March 2008

AbstractA three‐antenna MIMO system capable of generating a wide operating bandwidth of 2400–5850 MHz for access‐point applications is introduced. The proposed design is based on a bent metal‐plate monopole antenna with a compact size of 20 × 20 × 14 mm3. The three antennas are equally spaced along the perimeter of a circular ground and all generate a wide bandwidth of larger than 4 GHz. With the antenna short‐circuiting facing the center of the ground, not only the overall antenna size is reduced but also good isolation of less than −20 dB can easily be obtained. Calculated envelope correlation is also less than 0.002 across the operating band. The design prototype of the antenna is discussed in detail in the article. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1146–1148, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23333
Design of compact, wide‐band bandstop filters with sharp‐rejection characteristics
Authors: Kanti Mandal Mrinal , Divyabramham Kandimalla , Sanyal Subrata 
Published: March 2008

AbstractIn this study, a novel transmission line configuration has been proposed to design a sharp‐rejecting, compact bandstop filter with wide rejection‐bandwidth. Signal interference technique is used to obtain transmission zeros, which provide the sharp rejection characteristic. Rejection bandwidth is controlled by the characteristic impedances of transmission lines. Filter is analyzed using transmission line model. Theoretical predictions have been verified by the measurements of two compact filters fabricated in microstrip line. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1244–1248, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23335
Modified circular monopole antenna with improved transmission performance for UWB communications
Authors: Wu Qi , Jin Ronghong , Geng Junping 
Published: March 2008

AbstractThis study theoretically analyses the transmission performance of UWB antennas and presents a design methodology for improving the transmission performance of printed monopoles. Using this methodology, a modified circular monopole are proposed and analyzed as the design example. Both measured and simulated results are provided and discussed for verifying the validity of proposed design methodology. In a typical lab environment, the deleterious multi‐path transmission effects on the transfer function of the example antenna pair were observed and discussed. This optimization methodology would not bring any size or cost increase to the printed monopoles, and the improvement of transmission performance is quite discernible, which appears to be a significant improvement over printed UWB monopoles. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1285–1289, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23336
A novel compact dual‐band bandpass filter using asymmetric SIRs for WLANS
Authors: Chang Yu‐Chi , Kao Chia‐Hsiung , Weng Min‐Hang , Yang Ru‐Yuan 
Published: March 2008

AbstractIn this article, a novel compact dual‐band bandpass filter (BPF) using asymmetric stepped impedance resonators (SIRs) has been presented for the first time. The feature of the proposed asymmetric SIR is only one step discontinuity, which is different from the conventional SIR with two step discontinuities. The frequency response of the dual‐band at 2.4/5.2 GHz can be achieved by determining the impedance ratio (K) and physical length ratio (α) of the asymmetric SIR. The coupling coefficient between the coupled asymmetric SIRs is calculated by using full‐wave simulator IE3D. A dual band BPF is designed, fabricated, and measured. The measured results are in good agreement with the full‐wave simulation results. Additionally, the BPF has a smaller circuit size in comparison of previous works. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1237–1240, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23339
Tunable ring laser based on a semiconductor optical amplifier at 1300 nm using a simple wavelength selection filter
Authors: Jeon Mansik , Kim Jeehyun , Song Jae‐Won , Lee Ho , Choi Sanghoon , Nelson J. Stuart 
Published: March 2008

AbstractA simple, compact, and low cost tunable ring laser with a commercial semiconductor optical amplifier (SOA) was demonstrated. The tunable ring laser is based on an external wavelength filter cavity that is analogous with the Littman configuration with a diffraction grating, a mirror, and a simple slit. The unique structural advantage of this new system is that the slit is displaced to select a desired wavelength instead of tilting the mirror as in the Littman configuration. This allows easy control over the selected wavelength by the translating action of the slit. The full width half maximum (FWHM) wavelength turning range is 45 nm, and the wavelength resolution is about 2 pm. The demonstrated tunable ring laser has 2 mW output power. The side mode suppression ratios is 70–73 dB. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1317–1320, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23340
Design and analysis of wideband double‐sided printed spiral‐dipole antenna with capacitive coupling
Authors: Rmili Hatem , Floc'h Jean‐Marie 
Published: March 2008

AbstractA compact and wideband printed dipole antenna is presented for C‐ and X‐applications. The proposed balun‐fed antenna consists of a double‐sided printed dipole structure with a microstrip‐fed modified spiral‐dipole printed on the top side of the substrate, and a capacitive‐coupling rectangular‐patch, a connecting strip line and the ground plane printed on the bottom side. For the proposed antenna, a wide resonant band which extends from 6.27 to 12.47 GHz, with a fractional bandwidth of 66%, is observed. Details of the experimental and simulation results are presented and discussed. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1312–1317, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23341
Internal multiband surface‐mount monopole slot chip antenna for mobile phone application
Authors: Chang Chih‐Hua , Wong Kin‐Lu 
Published: March 2008

AbstractA multiband monopole slot chip antenna surface‐mountable on the system circuit board of the mobile phone is presented. The antenna comprises two monopole slots of different lengths, which are folded and attached onto a foam base in the study. With a compact volume of 30 × 10 × 8 mm3(2.4 cm3), the antenna can generate a lower band at about 900 MHz to cover GSM operation and a very wide upper band (bandwidth >1 GHz) to cover DCS/PCS/UMTS operation and 2.4 GHz WLAN operation. It is also promising to use a ceramic base of relative permittivity 7.8 to replace the foam base of the antenna. In this case, the antenna volume can be reduced to be 24 × 10 × 8 mm3(1.92 cm3) only, yet still capable of covering GSM/DCS/PCS/UMTS quad‐band operation. The proposed antenna is studied, and obtained results are presented and discussed. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1273–1279, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23342
Quarter‐band internal antenna design using three branches for GPS, UMTS/WCDMA, ISM, and SDMB band operation
Authors: Jang Byung‐chan , Kim Che‐young , Park Jeung‐keun 
Published: March 2008

AbstractA design scheme of a quarter‐band internal antenna is proposed for use in GPS, UMTS/WCDMA, ISM, and SDMB bands. The folded metal plates of the three branches are mounted on a dielectric‐coated ground plane for size miniaturization and durability. For a multiband operation the sectional antenna corresponding to each band was designed, combined, and finally trimmed. The return loss of the suggested antenna was calculated by a commercial HFSS simulator and the results are compared with measured return loss, which shows a good agreement between them. Gain and radiation pattern are also measured by the field measurement system in an anechoic chamber. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1227–1232, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23345
A singularity extraction technique for computation of antenna aperture fields from singular plane wave spectra
Authors: Cappellin Cecilia , Breinbjerg Olav , Frandsen Aksel 
Published: March 2008

AbstractAn effective technique for extracting the singularity of plane wave spectra in the computation of antenna aperture fields is proposed. The singular spectrum is first factorized into a product of a finite function and a singular function. The finite function is inverse Fourier transformed numerically using the Inverse Fast Fourier Transform, while the singular function is inverse Fourier transformed analytically, using the Weyl‐identity, and the two resulting spatial functions are then convolved to produce the antenna aperture field. This article formulates the theory of the singularity extraction technique and illustrates the effect of this for an array of electric Hertzian dipoles. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1308–1312, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23346
Strategies for the miniaturization of metamaterial resonators
Authors: Aznar Francisco , García‐García Joan , Gil Marta , Bonache Jordi , Martín Ferran 
Published: March 2008

AbstractIn this article, different possibilities to enhance the miniaturization of metamaterial resonant particles are presented and discussed. By using two metal layers connected by vias, new compact topologies useful for the synthesis of metamaterials (including left handed structures) are proposed. A comparative analysis of the different topologies, in terms of size and unloaded quality factor is carried out, and relevant conclusions are inferred. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1263–1270, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23348
Aperture‐coupled UHF RFID reader antenna for a handheld application
Authors: Lee DongHyun , Park PilJun , Kim JeongPyo , Choi JaeHoon 
Published: March 2008

AbstractThis article presents a new UHF RFID reader antenna for a handheld reader system. An aperture‐coupled structure is employed to cover the North American UHF RFID frequency band: 902–928 MHz. A thick high‐dielectric substrate with a relative permittivity of εr = 8 is used for the size reduction. The rectangular stubs on the proposed annular ring patch contribute to effective impedance matching and good axial ratio performance. The proposed antenna has a total volume of 100 mm × 100 mm × 9.6 mm and exhibits a maximum RHCP gain of 2.68 dBi and an average axial ratio of 1.1 dB for the application frequency band. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1261–1263, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23349
Nonlinear propagation and wave mixing characteristics of pulses in semiconductor optical amplifiers
Authors: Kumar Das Narottam , Chandra Karmakar Nemai 
Published: March 2008

AbstractNonlinear propagation and wave mixing characteristics of pulses in semiconductor optical amplifiers (SOAs) are analyzed using the finite‐difference beam propagation method (FD‐BPM). From the analyzed output waveform it is found that the peak positions of pulses are shifted to the leading edge. The output spectra are red‐shifted and the dips are found at the higher frequency side in the frequency spectra. Two pulses propagate in SOAs and four‐wave mixing (FWM) characteristics are obtained. Next, all‐optical demultiplexing (DEMUX) characteristics of pulses in SOAs based on FWM are analyzed. From this analysis, it is clear that the SOAs with wider gain bandwidth are required for faster DEMUX operation. The DEMUX characteristics from the time‐multiplexed signals by the repetitive pump pulses are also analyzed. The FWM signal intensity decreases with the strong pump pulses. However, there is no pattern effect due to gain saturation of pulses, because the pump pulses are injected continuously. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1223–1227, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23350