bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dual‐band printed dipole antenna with wide beamwidth for WLAN access points
Authors: Ta Son Xuat , Han Jea Jin , Choo Hosung , Park Ikmo 
Published: September 2012

AbstractIn this article, we propose a dual‐band angled printed dipole antenna with wide beamwidth for use in the access points of wireless local area network operating in the 2.4‐ and 5‐GHz bands.The antenna is fed by a novel integrated balun consisting of a curved microstripline and a circular slot for broadband operation. An angled dipole and two vertical copper plates on the ground plane are used to achieve wide beamwidth in the lower and upper bands, respectively. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2806–2811, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27176
Calculation of wave propagation parameters in generalized media
Authors: Obelleiro Fernando , Taboada José M. , Araújo Marta G. 
Published: September 2012

AbstractNanoscience and nanotechnology have brought new electromagnetic problems for which special considerations must be considered.We deep into the understanding of the mathematics and wave physics associated with them, focusing in the adequate derivation of the main electromagnetic wave parameters to obtain an efficient and straightforward implementation without special considerations. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2731–2736, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27179
Printed RFID reader antenna with circular polarization for handheld operation
Authors: Lin Shun‐Yun , Lin Yu‐Chih 
Published: September 2012

AbstractA novel circularly polarized antenna for ultrahigh frequency (UHF) radiofrequency identification (RFID) readers is proposed in this article. A prototype that operates in the UHF RFID band is successfully developed using an orthogonally truncated radiation patch, an obliquely slotted ground plane, and a 50‐Ω microstrip line that proximally fed the antenna. All elements are printed on a microwave substrate in a vertical structure. The antenna dimension of 65 × 900 × 8 mm3 is suitable to use for handheld devices. The impedance bandwidth for 2.5 VSWR and the 3‐dB axial‐ratio bandwidth is 15.2% (880 MHz∼1025 MHz) and 6.5% (890 MHz∼950 MHz), respectively. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2792–2797, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27180
Dual‐band microwave device for sensing dielectric property changes in microfluidic channels
Authors: Shao Jin , Manandhar Gaurav , Arigong Bayaner , Zhang Hualiang 
Published: September 2012

AbstractWe propose a dual‐band microwave device to detect the dielectric changes in polydimethylsiloxane microfluidic channels. Such a device, which consists of two dual‐band Wilkinson power dividers (working at 2 and 5 GHz) and two 90° dual‐band microstrip lines (providing 180° phase difference at two operating frequencies), is very sensitive for identifying dielectric material changes. Moreover, by operating at two frequencies simultaneously, it can improve the measurement stability/robustness. Compared with other existing microwave microfluidic sensors, the proposed device features enhanced measurement stability with the same level of measurement sensitivity (up to −80 dB cancellation level). © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2691–2694, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27188
An ultra‐wideband CPW‐fed monopole antenna with fan‐shaped structure
Authors: Wang Chen , Yan Ze‐Hong , Li Bo , Li Sheng 
Published: September 2012

AbstractIn this article, we present a novel ultrawideband (UWB) coplanar waveguide fed printed monopole antenna with fan‐shaped structure. Its UWB‐related performances are simulated and experimentally verified. The fabricated antenna occupies a small area, exhibits omnidirectional radiation pattern and good gains within the operating band, which illuminates the fan‐shaped structure is also a good candidate for UWB antenna design. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2878–2880, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27218
Heterogeneous uncoordinated deployment of WLANs: an evolving problem for current and future Wi‐Fi access
Authors: Abusubaih Murad 
Published: September 2012

SUMMARYThis article addresses the problem of uncoordinated heterogeneous deployment of 802.11 wireless local area networks (WLANs). It is expected that such deployments by different WLAN owners and WiFi providers will become a challenging problem that limits the network performance and quality of service of wireless users. We present results of a real case study that show a need for coordination among WLAN devices in order to avoid current and future problems. We provide potential solution directions. A special focus is given to channel assignment and coordinated channel access problems. Our results show that a new paradigm for designing WLAN devices seems to be crucial. Copyright © 2012 John Wiley & Sons, Ltd.
A model of antecedents of consumers' post brand attitude upon exposure to a cause–brand alliance
Authors: Myers Beth , Kwon Wi‐Suk 
Published: September 2012

A cause–brand alliance is a type of cause‐related marketing campaign in which the brand supports a cause in response to a consumer purchasing a product associated with the brand. Using the meaning transfer, attribution, and schema theories, the researchers developed a model and hypotheses addressing structural relationships among key antecedents of brand attitude change upon encountering a cause–brand alliance. The model and the hypotheses were tested in the context of hypothetical cause–brand alliance scenarios. Findings indicate cause–brand alliance attitude as a strong direct predictor of post brand attitude, whereas cause involvement, perceived brand motivations, and prior brand attitude indirectly predict post brand attitude through their effects on cause–brand alliance attitude. Cause–brand fit also indirectly predicts cause–brand alliance attitude via perceived brand motivations. Managerial and theoretical implications are discussed.Copyright © 2012 John Wiley & Sons, Ltd.
The influence of injection molding parameters and blowing agent addition on selected properties, surface state, and structure of HDPE parts
Authors: Bociaga Elzbieta , Palutkiewicz Pawel 
Published: September 2012

AbstractThe investigation of the influence of injection molding parameters (injection velocity, mold temperature and injection temperature, and additionally, as a result of these three parameters change, injection time, hold time, and cooling time) and blowing agent percentage on selected properties of HDPE molded parts such as weight, density, mechanical properties (tensile strength and elongation at maximum force), surface state (gloss and color), and structure was the aim of this work. The examination showed, that the mold temperature has the main influence on properties and surface state of molded parts from solid and foam HDPE. The weight, density, mechanical properties and gloss of molded parts increased with the increase in mold temperature. The mold temperature also influences significantly the number and size of pores in molded parts. The addition of blowing agent in a quantity of 2% is sufficient to obtain parts with favorable mechanical properties and good surface quality. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers.
Properties of thermoplastic starch and TPS/polycaprolactone blend reinforced with sisal whiskers using extrusion processing
Authors: Campos A. , Teodoro K.B.R. , Teixeira E.M. , Corrêa A.C. , Marconcini J.M. , Wood D.F. , Williams T.G. , Mattoso L.H.C. 
Published: September 2012

AbstractSisal whiskers (SW) were prepared by acid hydrolysis for subsequent evaluation as reinforcing material for biodegradable matrices of thermoplastic starch (TPS) and TPS/polycaprolactone (TPS/PCL) blends. The acid hydrolyzed SW had dimensions of 5 ± 2 nm in diameter and 210 ± 60 nm in length and 78% crystallinity. The nanocomposite blends consisted of whisker contents of 5 and 10 wt% and were coextruded with either TPS or TPS/PCL which formed the matrix material. The influence of SW on the morphology, crystallinity, thermal properties, mechanical behavior, structural, and biodegradation of TPS and TPS/PCL matrices were investigated. The lower SW content of 5 wt% dispersed and interacted well with both matrices. The introduction of PCL in the TPS matrix leads to an increased crystallinity and there was evidence that the carbonyl groups of PCL interacted with the OH groups on the surface of the whiskers. Addition of PCL decreased the whisker/whisker interaction over TPS alone, favoring the dispersion of the whiskers in the matrix and, consequently, the reinforcement effect was more pronounced in TPS/PCL blends than in the pure TPS matrix. The addition of the whiskers as reinforcement increased the biodegradability of TPS and TPS/PCL matrices. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers.
Effect of heating and stretching polyacrylonitrile precursor fibers in steam on the properties of stabilized fibers and carbon fibers
Authors: Qin Xianying , Lu Yonggen , Xiao Hao , Zhao Weizhe 
Published: September 2012

AbstractPolyacrylonitrile (PAN) fibers were heated and stretched in a steam bath mixed with nitrogen in the early stage of stabilization. During this process, the flexible linear chain of PAN molecule was converted to a rigid ladder structure by intramolecular cyclization. The shrinkage tension along the fiber axis decreased during this heat treatment, because water molecules here acted as a plasticizer for stretching. Consequently, the preferred orientation of ladder molecules in the stabilized fibers was enhanced. As a result, the preferred orientation, crystallite dimensions, and mechanical properties of the resultant carbon fibers (CFs) and graphite fibers (GFs) were improved, comparing with the corresponding CFs and GFs without pretreatment in the steam bath. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers.
Preparation and properties of carbon nanotube composites with nitrile‐ and styrene‐butadiene rubbers
Authors: Kummerlöwe Claudia , Vennemann Norbert , Yankova Ekaterina , Wanitschek Mirko , Größ Catharina , Heider Thomas , Haberkorn Frank , Siebert Achim 
Published: September 2012

AbstractThe work deals with the preparation and characterization of elastomer/multiwalled carbon nanotube (CNT) composites. Nitrile‐butadiene‐rubber (NBR), emulsion styrene‐butadiene‐rubber (E‐SBR) with random segment distribution, and solution styrene‐butadiene‐rubber (S‐SBR) having a blocked styrene content were used as elastomer matrix. The preparation of composites by a masterbatch process was compared to the direct melt‐mixing process using two different types of multiwalled CNT. It turned out that extremely low‐percolation thresholds of ∼0.2 and 1 wt% CNT can be reached by direct melt mixing of Nanocyl 7000 CNT with S‐SBR and NBR, respectively. The effect of CNT on the vulcanization reaction was studied by application of a first‐order kinetic model. It can be shown that the rate constants are decreasing with increasing CNT content especially at higher reaction temperatures and that CNT cause a decrease in activation energies. Temperature scanning stress‐relaxation measurements were used to prove the reinforcing effect of the CNT, to verify the phase structure of the S‐SBR, and to estimate the effect of CNT on crosslink density. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
p‐Type conductivity of GeTe: The role of lone‐pair electrons
Authors: Kolobov Alexander V. , Fons Paul , Tominaga Junji 
Published: September 2012

AbstractChalcogenide alloys are usually p‐type semiconductors. In GeTe, it was recently argued that p‐type conductivity results from vacancies on Ge sites. In this work, we demonstrate that the creation of vacancies in GeTe, in which the co‐existence of conventional covalent and dative bonds utilising the Te lone‐pair (LP) electrons makes Ge(3):Te(3) bonding geometry possible, results in the formation of a triad of twofold coordinated Te atoms. Because of the different nature of bonding (conventional covalent vs. dative), only one of the three Te atoms naturally possesses LP electrons after rupture of the Ge–Te bonds. As a result of electron redistribution, three twofold coordinated Te atoms with LP electrons and concomitantly holes in the valence band are generated, which provides a natural explanation of p‐type conductivity. We argue that a similar mechanism may be also operative in S‐ and Se‐based alloys, providing a general explanation of p‐type conductivity in chalcogenides.
Quantum phase transition in a dimerized chain with hexameric distortion
Authors: Naseri Mahboobeh Shahri , Japaridze George I. , Mahdavifar Saeed , Shayesteh Saber Farjami 
Published: September 2012

AbstractWe consider the dimerized spin‐1/2 Heisenberg chain with spin hexameric distortion of the exchange pattern and study the zero‐temperature phase diagram in the parameter space (J1, J2, J3) by a continuum‐limit bosonization approach and the exact diagonalization method. The phase diagram is rich and has two gapped dimer phases. We obtain an estimate of the critical line separating the different gapped dimer phases by the bosonization approach. The existence of the transition line and the difference between dimer phases is checked numerically. The behavior of the energy gap and the dimer order parameter supports the exact location of the gapless line.
Investigation of bond dilution effects on the magnetic properties of a cylindrical Ising nanowire
Authors: Yüksel Yusuf , Akıncı Ümit , Polat Hamza 
Published: September 2012

AbstractA cylindrical magnetic nanowire system composed of ferromagnetic core and shell layers has been investigated by using effective field theory (EFT) with correlations. Both ferromagnetic and antiferromagnetic exchange couplings at the core–shell interface have been considered. Main attention has been focused on the effects of the quenched disordered shell bonds, as well as interface bonds on the magnetic properties of the system. A complete picture of the phase diagrams and magnetization profiles has been represented. It has been shown that for the antiferromagnetic nanowire system, the magnetization curves can be classified according to Néel theory of ferrimagnetism and it has been found that under certain conditions, the magnetization profiles may exhibit Q‐type, P‐type, N‐type, and L‐type behaviors. The observed L‐type behavior has not been reported in the literature before for the equilibrium properties of nanoscaled magnets. As another interesting feature of the system, it has been found that a compensation point can be induced by a bond dilution process in the surface.
Classifying different denial‐of‐service attacks in cloud computing using rule‐based learning
Authors: Khorshed Md Tanzim , Ali A B M Shawkat , Wasimi Saleh A. 
Published: September 2012

ABSTRACTFrom traditional networking to cloud computing, one of the essential but formidable tasks is to detect cyber attacks and their types. A cloud provider's unwillingness to share security‐related data with its clients adds to the difficulty of detection by a cloud customer. The research contributions in this paper are twofold. First, an investigative survey on cloud computing is conducted with the main focus on gaps that is hindering cloud adoption, accompanied by a review of the threat remediation challenges. Second, some thoughts are constructed on novel approaches to address some of the widely discussed denial‐of‐service (DoS) attack types by using machine learning techniques. We evaluate the techniques' performances by using statistical ranking‐based methods, and find the rule‐based learning technique C4.5, from a set of popular learning algorithms, as an efficient tool to classify various DoS attacks in the cloud platform. The novelty of our rather rigorous analysis is in its ability to identify insider's activities and other DoS attacks by using performance data. The reason for using performance data rather than traditional logs and security‐related data is that the performance data can be collected by the customers themselves without any help from cloud providers. To the best of our knowledge, no one has made such attempts before. Our findings and thoughts captured through a series of experiments in our constructed cloud server are expected to give researchers, cloud providers and customers additional insight and tools to proactively protect themselves from known or perhaps even unknown security issues that have similar patterns. Copyright © 2012 John Wiley & Sons, Ltd.
Does antenatal ultrasound labeling predict birth order in twin pregnancies?
Authors: D'Antonio F. , Dias T. , Thilaganathan B. ,   the Southwest Thames Obstetric Research Collaborative (STORK)
Published: September 2012

ABSTRACTObjectiveIt is often assumed by obstetricians, neonatologists and parents that the prenatal nomenclature used to identify twins on ultrasound is consistent with twin labeling after their birth. The aim of this study was to use a large regional database of twin ultrasound scans to validate the effectiveness of a scan before delivery in predicting twin birth‐order.MethodsA large regional database of twin ultrasound scans with data from nine hospitals over a 10‐year period was used to identify all ultrasound examinations carried out just before birth. The discordance in twin order between the last scan and birth was evaluated by observing discrepancies in fetal sex and weight.ResultsIn total, 2103 twin pregnancies with ultrasound estimated fetal weights (EFWs) and birth weights were assessed. Of these, fetal sex was recorded in 149 different‐sex pregnancies. Discrepancy between antenatal labeling and the anticipated birth order was noted in 37.6% (56/149) of cases when judged by sex discordance and in 36% (757/2103) of cases when judged by weight discordance. Multiple logistic regression analyses demonstrated that weight discordance, but not chorionicity, scan‐to‐delivery interval, gestation at scan or gestation at delivery, significantly influenced the change in birth order (P < 0.001).ConclusionAntenatal ultrasound labeling does not predict twin birth‐order in a significant proportion of twin deliveries. This finding should be borne in mind not only by parents, but also by physicians when delivering twins discordant for anomalies that are not evident on external examination. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Amplitude modulations in planetary gears
Authors: Luo Huageng , Hatch Charles , Hanna Jesse , Kalb Matt , Weiss Adam , Winterton John , Inalpolat Murat , Dannehy Christopher 
Published: September 2012

ABSTRACTA planetary gear set introduces complicated gear vibration frequency structures, especially in sequentially phased planetary gear sets. Frequency components from a fixed sensor can be enhanced and/or canceled with different planets and ring gear configurations. In this study, an amplitude modulation based formula and simple trigonometric function manipulations are used to reveal the major physical phenomena in a planetary gearbox. The formulation used in this study permits unlimited modulation indices as well as unrestricted planet passing signal responses sensed at fixed transducer locations on the gearbox. Numerical simulations and field examples are given in the end of the paper to validate the analysis. Copyright © 2012 John Wiley & Sons, Ltd.
In situ Neutron Diffraction as a Probe on Formation and Decomposition of Nitrides and Hydrides: A Case Study
Authors: Widenmeyer Marc , Niewa Rainer , Hansen Thomas C. , Kohlmann Holger 
Published: September 2012

AbstractIn order to perform real‐time studies of solid‐gas reactions involving light elements such as hydrogen and nitrogen, gas pressure and gas flow cells were developed for in situ neutron powder diffraction. The gas pressure cell is based on a sapphire single crystal tube as a sample holder and provides high quality diffraction patterns with very low background up to 16.0 MPa hydrogen (deuterium) gas pressure and temperatures up to 400 °C. The gas flow cell contains a silica tube as sample container and is optimized for flowing ammonia as reaction gas. While it produces higher background owing to the silica, it allows much higher temperatures of up to 750 °C to be used. For both cells heating is realized contactless and without any contribution to the diffraction patterns by two lasers and so high‐quality diffraction data allowing for a detailed Rietveld analysis can be collected on D20 (Institute Laue‐Langevin) with a one minute time resolution. Examples are presented demonstrating the potential of the in situ gas cells, ranging from the nitridation of vanadium and iron powders with flowing ammonia, to the deuteration of palladium and the hydrogen storage material LaNi5.
Hydrothermal Synthesis, Structure, Magnetic, and Photoluminescent Properties of a Heterometallic Cobalt(II)/Cerium(III) Coordination Compound with the Ligand Pyrazine 2, 3‐di­carboxylic Acid
Authors: Wei Qing , Zhang Sheng , Yang Qi , Chen San‐Ping , Gong Wen‐Jun , Zhang Yu‐Ping , Zhang Guo‐Chun , Zhou Chun‐Sheng , Gao Sheng‐Li 
Published: September 2012

AbstractHydrothermal reaction of the metalloligand {[Co(Pzdc)2]·2H2O}n (1) with Ce(NO3)3·6H2O yields a heterometallic 3d‐4f coordination compound {[Ce2Co(Pzdc)4(H2O)6]·2H2O}n (2) (H2Pzdc = pyrazine 2, 3‐dicarboxylic acid). X‐ray structure determination, IR spectroscopy, elemental analysis, thermogravimetric analysis, and magnetic property for the targets are presented. Compound 1 affords one‐dimensional double zigzag chains. Compound 2 features a three‐dimensional CoII–CeIII herringbone structure, in which the slightly deformational 1 and central CeIII atoms are linked by Pzdc2– spacers, and is further analyzed with {4.62}2{42.62.82}{63}2{65.8}2 topology symbol. Magnetic property analysis reveals that the antiferromagnetic interactions occur in compound 2 due to a long‐range superexchange pathway between adjacent magnetic centers. In addition, the solid state photoluminescence of 2 was investigated.
Synthesis and Characterization of Energetic Salts of the (C4N122–) Dianion
Authors: Klapötke Thomas M. , Piercey Davin G. , Rohrbacher Florian , Stierstorfer Jörg 
Published: September 2012

Abstract3, 6‐Bis(tetrazol‐5‐yl)‐1, 2, 4, 5‐tetrazine is a nitrogen‐rich energetic compound readily prepared and a strong dibasic acid. By the reaction with energetic bases such including hydroxylamine, triaminoguanidine, hydrazine, and diaminourea, multiple ionic energetic materials were prepared and characterized for the first time. Both chemical (multinuclear NMR, Infrared, Raman, MS, etc) as well as explosive (Impact, Friction, Static sensitivities) properties are reported. The materials prepared, with the exception of the silver salt, which is a primary explosive, fall into the classification of low‐sensitivity energetic materials due to desensitizing hydration waters. Calculated explosive performances using the EXPLO5 computer code are also reported.
Hereditäre Fiebersyndrome
Authors: Schumacher J. , Timmann C. 
Published: September 2012

Zusammenfassung
Das familiäre Mittelmeerfieber (FMF), Hyper-IgD-Syndrom (HIDS) und das Tumornekrosefaktor(TNF)-Rezeptor-1-assoziierte periodische Syndrom (TRAPS) sind monogene Krankheiten, die unter dem Begriff der hereditären Fiebersyndrome zusammengefasst werden. Sie sind durch rezidivierende Episoden mit Fieber und Entzündungszeichen gekennzeichnet und werden von Mutationen in Genen verursacht, denen eine Funktion bei der angeborenen Immunität zukommt. Die vorliegende Übersichtsarbeit befasst sich mit dem klinischen Erscheinungsbild und der Genetik der hereditären Fiebersyndrome. Sie sind für die humangenetische Beratung von Bedeutung.