bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of a very compact U‐HI‐LO low‐pass filter using meander technique and quasi horn inductors for L‐band and C‐band applications
Authors: Boutejdar Ahmed 
Published: September 2016

ABSTRACTIn this article, a novel very compact low pass filters, using Hi‐Lo technique and meander method are proposed. The several proposed filters are designed using a modification along the microstrip line by addition of U form and a meander shape. The compact meander LPF consists of two thin microstrip lines, which are connected with 50‐Ω microstrip feed lines and thus with the both SMA connectors and a width microstrip patch placed in the middle of the structure. This meander Hi‐Lo topology has been placed on the RO4003 substrate with a relative dielectric constant εr = 3.38 and thicknesses h = 0.813 mm and a loss tangent of 0.0027. Additionally to a very good compactness, the structure exhibits simple design and fabrication, very low insertion loss in the passband of 1.5 dB, and it achieves a wide rejection bandwidth with overall 20 dB attenuation from 5.7 to 6.3 GHz. The compact low pass structure occupies an area of (0.337 λg × 0.253 λg) where λg = 60 mm is the wavelength at the cut‐off frequency 2.75 GHz. The simulated and measured results show good agreement and validate the proposed approach. Such compact filter structures are used in various microwave system applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2897–2901, 2016
Inverse class‐FX‐band SiGe HBT power amplifier with 44% PAE and 24.5 dBm peak output power
Authors: Song Ickhyun , Ulusoy Ahmet Çağrı , Oakley Michael A. , Ju Inchan , Cho Moon‐Kyu , Cressler John D. 
Published: September 2016

ABSTRACTAn X‐band power amplifier (PA) implemented in a silicon‐germanium (SiGe) heterojunction bipolar transistor technology is presented. The SiGe PA was designed for inverse class‐F mode using thin‐film microstrip (TFMS) lines, eliminating the use of conventional band‐limiting lumped inductors and transformers. Thus, simultaneous high efficiency and minimized in‐band variation were achieved for X‐band (8–12 GHz) applications. In addition, for boosting peak output power (Pout), the common‐base transistor in the PA core was designed to operate in a weak avalanche region, which allowed dynamic collector‐to‐base voltage to swing beyond the collector‐base breakdown voltage with open emitter without performance degradation. The fabricated SiGe PA demonstrates a high power‐added efficiency (PAE) of 43.2% and a peak Pout of 24.3 dBm at 10 GHz. Benefitting from the utilization of TFMS lines, the PA exhibits a flat response for both PAE (33.3–44%) and peak Pout (23.1–24.5 dBm) for the entire X‐band frequency range. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2868–2871, 2016
Performance of microstrip patch antenna due EBG/PBG arrangements insertion
Authors: da Silva José L. , de Andrade Humberto D. , Maia Anamaria S. , Fernandes Humberto C. C. , da Silva Isaac B. T. , Sombra Antônio S. B. , Pereira Jonathan P. P. 
Published: September 2016

ABSTRACTThis paper aims to present microstrip patch antenna prototypes with rectangular patch, where structures of photonic band gap and electromagnetic band gap in cylindrical geometry for different drilling heights were performed in the substrate. The main radiations properties were simulated using Finite Element Method (FEM) and compared with the measured results of the manufactured devices. A current surface reduction can be observed due EBG/PBG insertion and a measurement matching of return loss values, enabling the application on wireless communication. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2933–2937, 2016
A tunable bandstop filter using triangular patch resonator with defected ground structures
Authors: Pinheiro J.M. , Serrano A.L.C. 
Published: September 2016

ABSTRACTA tunable dual‐mode bandstop patch filter with two degrees of liberty controlling the filter's central frequency and bandwidth is presented. The bandstop filter uses a single triangular resonator miniaturized by two slots and two defected ground structures (DGSs) slots to improve rejection. Varactor diodes are used across the patch's slots to vary the frequency of each degenerate fundamental mode. The models used in simulations, varactors assembling, DC bias configuration and measured results are presented. The proposed filter presents 17% of center frequency tuning range in the 5.8 GHz WiMAX band and the fractional bandwidth can be varied from 1.8% to 18%. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2930–2933, 2016
A positioning algorithm realized multilateration for distributed fiber‐optic sensor
Authors: Ye Zi , Wang Jian , Wang Chao , Jia Bo 
Published: September 2016

ABSTRACTBased on a distributed fiber‐optic sensor with a hybrid configuration of Mach‐Zehnder and Sagnac interferometer, cepstrum method is proposed in this paper to realize multilateration by estimating time delay. Compared with traditional null frequency method and autocorrelation algorithm, cepstrum method showed much better location accuracy. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2913–2917, 2016
an ultra‐wideband bandpass filter with high return loss and controllable notch band
Authors: Kim Phirun , Chaudhary Girdhari , Jeong Yongchae 
Published: September 2016

ABSTRACTIn this paper, an ultra‐wideband (UWB) bandpass filter (BPF) with a high return loss and a notch band is proposed. A high return loss and a notch band can be obtained by controlling characteristics impedance of coupled line and length of the shut stubs, respectively. For the validation, the UWB BPF was designed and measured to obtain 20 dB return loss with a notch band at 5.5 GHz. The results presented indicated that the 20 dB return loss is extended from 2.93 to 5.1 GHz and 6.14 to 11 GHz. The maximum return loss and attenuation at the notch band of 5.6 GHz are 2.3 dB and 16 dB, respectively. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2922–2926, 2016
Experimental design of bandstop filters based on unconventional defected ground structures
Authors: Annam Kaushik , Kumar Khah Sunil , Dooley Steven , Cerny Charles , Subramanyam Guru 
Published: September 2016

ABSTRACTA modified design of band stop filters using unconventional defected ground structures (DGS) is presented. The new proposed structures have conventional dumbbell DGS and spiral DGS integrated with U‐slots. These microstrip structures provide high selectivity and Q‐factor. By integrating the U‐slot to the conventional structures, the overall capacitance and inductance increase which results in shift of resonance frequency from3.434 GHz to2.323 GHz for modified dumbbell and from 1.818 GHz to 1.702 GHz for modified spiral structure. Sharp transition is achieved from pass band to stop band and reduced ripples in the pass band for the new proposed DGS while the DGS sizes remain the same. The proposed designs were fabricated and tested on a dielectric substrate with dielectric permittivity of 10. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2969–2973, 2016
Compact triple‐band PIFA with high bandwidth and gain for multiple mobile services
Authors: Oliveira R. G. M. , Sales A. J. M. , Nascimento J. P. C. , Menezes J. W. M. , Silva M. A. S. , Sombra A. S. B. 
Published: September 2016

ABSTRACTA new planar triple band microstrip‐fed Planar Inverted‐F Antenna (PIFA) for the use in GSM835 band (698–989 MHz), DCS1940 band (1824–2033 MHz) and Wi‐Fi2340 band (2302–2548 MHz) is reported. A numerical study based on the parameters like ground plane length, height of radiating plate, feeding point position, shorting plate width, and position, was done to obtain an optimized antenna. The simulation allowed the characterization of the designed antenna as a function of different antenna parameters like S11, resonant frequency, bandwidth, gain, radiation pattern, and electric and magnetic fields distribution. A prototype was fabricated and the agreement with the simulations study was very good. The measured bandwidth of 34.73%, 48.47%, and 38.21% were obtained, respectively. The gain of 4.02 dBi, 2.47 dBi, and 4.93 dBi was also obtained for each band, respectively. The antenna also presents high efficiency of 53.19%, 49.07%, and 62.21%, respectively. The reported results show that this PIFA is suitable for mobile‐communication applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2960–2965, 2016
Low‐profile circularly polarized fabry–perot cavity antenna
Authors: Ratni Badreddine , de Lustrac André , Villers Serge , Nawaz Burokur Shah 
Published: September 2016

ABSTRACTThe modeling and characterization of a low‐profile circularly polarized directive antenna is reported. The proposed structure designed to operate near 2.1 GHz is evolved from a Fabry–Perot (FP) cavity with a patch antenna acting as the feed. One of the two reflectors is the antenna's ground plane and the other one is made from a bi‐layered metamaterial‐based partially reflecting surface (PRS) constituted by a capacitive and an inductive grid. The metasurface responds similarly to orthogonally polarized electric field. Calculations together with experimental results obtained from the fabricated prototype are presented. The results show a high directivity, low axial ratio and low level for the secondary lobes. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2957–2960, 2016
Compact 1 × 4 patch antenna array by means of EBG structures with enhanced bandwidth
Authors: Jam Shahrokh , Malekpoor Hossein 
Published: September 2016

ABSTRACTIn this paper, a novel design of compact 1 × 4 patch antenna array using electromagnetic band gap (EBG) for wideband operation is introduced. Three unequal arms fed by CPW‐to‐slotline through a coupling system of 100 Ω T‐shaped slotline transitions are utilized for broadening the impedance bandwidth with multiple resonances. By adding two conventional mushroom‐type EBG (CMT‐EBG) structures on both sides of 100 Ω slotline transitions, dual wideband patch array is obtained. The proposed 1 × 4 patch array with CMT‐EBG includes two bands with the measured ranges (S11≤−10 dB) of 6.71–6.97 GHz and 8.60–11.51 GHz. Moreover, more size reduction is achieved by using an edge‐shorted mushroom‐type EBG (ESM‐EBG) for the proposed array. This design with the ESM‐EBG indicates almost 37% size reduction compared with the proposed array without EBG. In this paper, an equivalent circuit model of the proposed 1 × 4 array with EBG is also introduced to describe the process of its bandwidth enhancement. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2983–2989, 2016
A superconducting manifold‐coupled triplexer with an iterative design method at X‐band
Authors: Song Xiaoke , Liu Yong , Wei Bin , She Yajun , Wang Honghua , Luo Tao , Cao Bisong , Lu Xinxiang , Jiang Ying 
Published: September 2016

ABSTRACTThis paper presents a superconducting manifold‐coupled narrowband triplexer at X‐band frequency. The high Q‐value resonator is adopted to create a filter with low insertion loss. Impedance matching and iterative design methods are used to design the duplexer and manifold structure. Furthermore, metal shielding plates are used to separate the three channels to suppress the box resonant modes. The three bandwidths of the superconducting triplexer are all 60 MHz, and the center frequencies are 9.0, 9.12, and 9.24 GHz. The triplexer exhibits good performance at 65 K, with an insertion loss of 0.7 dB at 9.24 GHz. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2949–2954, 2016
Design of a low‐profile H‐plane siw horn antenna with modified flare walls
Authors: Wang Xiaochuan , Han Xin , Lu Chao , lou Yihui , Lu Wenzhong 
Published: September 2016

ABSTRACTA low‐profile H‐plane horn antenna with modified flare walls based on the substrate integrated waveguide (SIW) technology is presented. To deal with the common problem of impedance mismatch in SIW horns built on thin substrates, modified flare walls consisting of a rolled edge section and a curved throat section are employed. In addition, the arc‐shaped grated transition, which can also lower the reflection coefficient, is introduced after the horn aperture. The antenna is implemented on a PTFE substrate. Measured |S11| of the proposed antenna is below −10 dB from 12.0 to 15.5 GHz. Therefore, the proposed design can achieve an enhanced bandwidth of 25.5% with a substrate thickness of only 0.092 λ0, showing good impedance matching performance. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:3012–3015, 2016
Four element half circle shape printed mimo antenna
Authors: Hassan A. T. , Sharawi M. S. 
Published: September 2016

ABSTRACTIn this work, a four element multiple‐input‐multiple‐output (MIMO) antenna system with half circle shape printed monopole antennas is presented. The antenna elements are designed on an FR4 substrate with dielectric constant 4.3 and dimensions of 110 × 60 × 0.8 mm3. These antennas are covering part of 4G and WLAN bands with maximum measured gain and efficiency of 3.12 dB and 81.5%, respectively, along with a −10 dB bandwidth of 230 MHz. The coupling between adjacent ports is at least −11 dB without using any technique for isolation enhancement. The MIMO antenna system has good pattern isolation such that the correlation coefficient is calculated using the measured three‐dimensional (3D) far field radiation pattern with a maximum value of 0.3 at 2.4 GHz. The proposed design can be used in handheld terminals. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2990–2992, 2016
Subwavelength operating metamaterial for multiband applications
Authors: Hossain M. J. , Faruque M. R. I. , Islam S. S. , Islam M. T. 
Published: September 2016

ABSTRACTIn this article, subwavelength operating double negative compact metamaterial was designed, fabricated, and measured that can operate in a multiband microwave frequency span. The proposed metamaterial structure offers miniaturization factor compared with traditional metamaterial unit‐cells and obeys better effective medium ratio. Commercially available Computer Simulation Technology electromagnetic simulator was adopted to investigate the design of the metamaterial. The subwavelength metamaterial displays multiband response in conjunction with left handed property over the certain frequency band in the microwave regime. In addition, the effective medium parameters of the metamaterial were studied. The dimensions and scattering parameters of the proposed double negative compact metamaterial are suitable for multiband applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:3004–3008, 2016
A bounding surface elasto‐viscoplastic constitutive model for non‐isothermal cyclic analysis of asphaltic materials
Authors: Shahbodagh B. , Habte M.A. , Khoshghalb A. , Khalili N. 
Published: September 2016

SummaryAn elasto‐viscoplastic constitutive model for asphaltic materials is presented within the context of bounding surface plasticity theory, taking into account the effects of the stress state, void binder degree of saturation, temperature and strain rate on the material behaviour. A stress state dependent non‐linear elasticity model is introduced to represent time‐independent recoverable portion of the deformation. The consistent visco‐plasticity framework is utilised to capture the rate‐dependent, non‐recoverable strain components. The material parameters introduced in the model are identified, and their determination from conventional laboratory tests is discussed. The capability of the model to reproduce experimentally observed response of asphaltic materials is demonstrated through numerical simulations of several laboratory test data from the literature. Copyright © 2016 John Wiley & Sons, Ltd.
A comparison of safety and efficacy of cytotoxic versus molecularly targeted drugs in pediatric phase I solid tumor oncology trials
Authors: Dorris Kathleen , Liu Chunyan , Li Dandan , Hummel Trent R. , Wang Xia , Perentesis John , Kim Mi‐Ok , Fouladi Maryam 
Published: September 2016

AbstractBackgroundPrior reviews of phase I pediatric oncology trials involving primarily cytotoxic agents have reported objective response rates (ORRs) and toxic death rates of 7.9–9.6% and 0.5%, respectively. These data may not reflect safety and efficacy in phase I trials of molecularly targeted (targeted) drugs.MethodsA systematic review of pediatric phase I solid tumor trials published in 1990–2013 was performed. The published reports were evaluated for patient characteristics, toxicity information, and response numbers.ResultsA total of 143 phase I pediatric clinical trials enrolling 3,896 children involving 53 targeted and 48 cytotoxic drugs were identified. A meta‐analysis demonstrated that the ORR is 2.1‐fold higher with cytotoxic drugs (0.066 vs. 0.031 per subject; P = 0.007). By contrast, the pooled estimate of the stable disease rate (SDR) is similar for cytotoxic and targeted drugs (0.2 vs. 0.23 per subject; P = 0.27). The pooled estimate of the dose‐limiting toxicity rate is 1.8‐fold larger with cytotoxic drugs (0.24 vs. 0.13 per subject; P = 0.0003). The hematologic grade 3–4 (G3/4) toxicity rate is 3.6‐fold larger with cytotoxic drugs (0.43 vs. 0.12 per treatment course; P = 0.0001); however, the nonhematologic G3/4 toxicities and toxic deaths occur at similar rates for cytotoxic and targeted drugs.ConclusionsIn phase I pediatric solid tumor trials, ORRs were significantly higher for cytotoxic versus targeted agents. SDRs were similar in targeted and cytotoxic drug trials. Patients treated with cytotoxic agents were more likely to experience hematologic G3/4 toxicities than those patients receiving targeted drugs.
An insight into the schizophrenic self‐assembly of thermo and proton sensitive graphene oxide grafted block copolymer
Authors: Maity Nabasmita , Kuila Atanu , Chatterjee Dhruba P. , Mandal Debasish , Nandi Arun K. 
Published: September 2016

ABSTRACTIn order to study the self‐assembly of block copolymer grafted from graphene oxide (GO) by the fluorescence of GO, poly(ε‐caprolactone) (PCL)‐block‐poly(dimethyl aminoethyl methacrylate) (PDMAEMA) is grafted from its surface using consecutive ring opening (ROP) and atom transfer radical polymerization (ATRP). GO‐g‐(PCL13‐b‐PDMAEMA117) (GPCLD) at pH 9.2 exhibits cloud point (Tc) at 32 °C. At pH 9.2 HRTEM images indicate schizophrenic morphology from vesicle at 26 °C to annular ring at 30 °C followed by giant size aggregation at 38 °C. But the reference block copolymer (PCL14‐b‐PDMAEMA126, PCLD), synthesized using benzyl alcohol as ROP initiator, exhibits only core–shell morphology whose size increases with rising temperature at pH 9.2. GPCLD solution exhibits good photoluminescence (PL) property arising from GO at pH 9.2 and PL‐intensity increases abruptly during phase transition. Both Tc and size of GPCLD assembly can be reversibly tuned by CO2 and N2 gas purging. 1H NMR spectra exhibit a gradual shift of resonance peaks of the protons on CO2 bubbling. Thus at pH 9.2 and at 38 °C the GPCLD acts as a good CO2 sensor. Additionally, the GPCLD vesicle can load hydrophobic guest molecules which can be released by triggering with CO2. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 3878–3887
A potential insect growth regulator for cockroach control: design, synthesis and bioactivity of N‐terminal‐modified allatostatin analogues
Authors: Wu Xiaoqing , Wang Meizi , Huang Juan , Zhang Li , Zhang Zhe , Ling Yun , Yang Xinling , Tobe Stephen S 
Published: September 2016

AbstractBACKGROUNDThe FGLa‐allatostatins (ASTs) are a family of neuropeptides that can inhibit juvenile hormone biosynthesis by the corpora allata (CA) in vitro, and therefore they are regarded as insect growth regulator (IGR) candidates for pest control. In our previous studies, an AST mimic, H17, was found to have a significant effect on JH biosynthesis by cockroach CA, both in vitro and in vivo. To discover new potential mimics and explore the substituent effect on the inhibition of JH biosynthesis, 30 analogues, modified with various substituents on the benzene ring at the N‐terminus of lead compound H17, were designed and synthesised. Their bioactivity in inhibiting JH biosynthesis by the CA of Diploptera punctata and the potency of M9, M10 and M11 in activation of Dippu‐AstR were evaluated.RESULTSAll the analogues showed an effect on JH biosynthesis by CA in vitro. M9, M10 and M11 can activate the Dippu‐AstR, albeit with much lower potency than that of AST 1. M11 also exhibited improved in vitro activity (IC50 6.98 nm) in comparison with the lead compound H17 (IC50 29.5 nm). In particular, M11 displayed good in vivo activity in inhibiting JH biosynthesis and basal oocyte growth.CONCLUSIONThe structure–activity relationship studies suggest that different positions of substituents on the benzene ring of the cinnamic acid can lead to different activities. The para‐substitution on the benzene ring plays an important role in inhibiting JH biosynthesis in vitro. Moreover, M11 is considered to be a potential IGR for cockroach control. © 2016 Society of Chemical Industry
Selective Lignin Oxidation towards Vanillin in Phenol Media
Authors: Luo Jizhong , Melissa Prawirasatya , Zhao Wenguang , Wang Zhan , Zhu Yinghuai 
Published: September 2016

AbstractSelective lignin oxidation reaction to produce vanillin was carried out in phenol media with a catalyst of γ‐Al2O3 supported ReOx nanoparticles. A vanillin yield of 7.3wt% was achieved under moderate reaction conditions of (120 °C and 2 bar oxygen) according to GC ananlysis. The vanillin selectivity is higher than 95.0 %. The catalyst could be separated conveniently from the product mixture and re‐used with sustainable activity in the processes.
Progress of Chiral Schiff Bases with C1 Symmetry in Metal‐Catalyzed Asymmetric Reactions
Authors: Hayashi Masahiko 
Published: September 2016

AbstractIn this Personal Account, various chiral Schiff base–metal‐catalyzed enantioselective organic reactions are reported; the Schiff bases used were O,N,O‐ as well as N,N,P‐tridentate ligands and N,N‐bidentate ligands having C1 symmetry. In particular, the enantioselective addition of trimethylsilyl cyanide, dialkylzinc, and organozinc halides to aldehydes, enantioselective 1,4‐addition of dialkylzinc to cyclic and acyclic enones, and asymmetric allylic oxidation are reported. Typically, ketimine‐type Schiff base–metal complexes exhibited higher reactivity and enantioselectivity compared with the corresponding aldimine‐type Schiff base–metal complexes. Notably, remarkable ligand acceleration was observed for all reactions. The obtained products can be used as key intermediates for optically active natural products and pharmaceuticals.