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A Linear Array Antenna of Microstrip Patch Antennas Fed by the Open-End of coplanar Waveguides

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Wireless Engineering and Technology 2017年第2期8卷 37-49页

作者： Toshihisa Kamei Hiromi Shima Syotaro Fukuda Seishiro Ishii Department of Communications Engineering National Defense Academy Yokosuka Japan Kamakami Architecture Design and Quantity Surveying Office Yamagata Japan

In this study, we constructed a 4-element linear array antenna using four 20 GHz band microstrip patch antennas with a structure such that the signal is fed to the patch antennas from open-end coplanar waveguides without contact. We investigated factors related to the design of linear array patch antennas. To adjust the maximum radiation direction and reduce return loss, we optimized the spacing between the elements and their shape. With an element spacing of 11.50 mm, patch width of 3.90 mm, and patch length of 4.15 mm, we obtained a resonance frequency of 20.05 GHz and a return loss of -29.59 dB at the resonance frequency. However, in the case of a 4-element linear array antenna structure, undesired resonances occurred in frequency bands other than the design resonance frequency band of 20 GHz. To suppress these undesired resonances and obtaining stable operation at the design frequency, we propose a new structure in which the feed line is loaded with a short stub, and show through computer simulations that the occurrence of undesired resonances can be sufficiently suppressed. Furthermore, we demonstrate the problem of radiation gain reduction caused by introducing a short stub, propose a design method for a new structure in which the feed line has slits between the stubs, and show improvement of the antenna gain by 0.5 dBi.

关键词： Microstrip Patch Antenna coplanar Waveguide Linear Array Antenna Short Stub Undesired Resonance Suppression

Dosimetric Study of coplanar and Non-coplanar Intensity-Modulated Radiation Therapy Planning for Esophageal Carcinoma

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2013年第4期2卷 133-138页

作者： Ying Li Bing Liu Fushan Zhai Yongfeng Yang Ming Liu Chaoen Bao Qingxiang Zhou Department of Radiation Oncology Third Hospital of Hebei Medical University Shijiazhuang China

Purpose: To compare the dosimetric impact of coplanar intensity modulated radiation therapy (IMRT) and non-coplanar IMRT for the esophageal carcinoma. Methods: There are forty-five esophageal carcinoma patients, fifteen of whom were cervical and upper thoracic (Group 1) and thirty were middle and lower thoracic (Group 2). Gross tumor volume (GTV), clinical target volume (CTV), and organs at risk (OAR) were contoured by the chief physician in the CMS-XiO treatment planning system. For each patient, one coplanar plan and two non-coplanar plans have been created using the same physical objective function. A detailed dose-volume histogram (DVH) comparison among three plans was then carried out in a tabulated format. Results: 1) In Group 1 patients with PTV volume less than 100cc, the mean dose and dose gradient of non-coplanar plan were much better than those in coplanar plan. 2) In Group 2 patients, the conformity index (CI) for coplanar and two non-coplanar plans were 0.69 ± 0.13, 0.41 ± 0.13, and 0.68 ± 0.15, respectively. The V5, V10, V20, and the mean dose to the lung were lower in the non-coplanar plans compared to ones in coplanar plan. However, the non-coplanar plans resulted in an increase in a dose to the heart, but the dose was still within heart toxicity tolerance. Conclusion: For Group 1 patients, the non-coplanar IMRT plan had less dose gradient and better mean dose than the coplanar IMRT plan. For Group 2 patients, the non-coplanar IMRT could the decrease dose to the lung tissue, thus lowering the probability of radiation pneumonia to esophageal cancer patients. The drawback of non-coplanar IMRT is that, even within toxicity tolerance, it could deliver a higher dose to the heart and spinal cord compared to the coplanar plan. Therefore, for patients with cardiology and neurology concern, non-coplanar IMRT should be used with caution.

关键词： Esophageal Carcinoma coplanar IMRT Non-coplanar IMRT

Techniques of microwave permeability characterization for thin films

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Chinese Physics B 2019年第9期28卷 37-49页

作者： Xi-Ling Li Jian-Bo Wang Guo-Zhi Chai Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000China Key Laboratory for Special Function Materials and Structural Design of the Ministry of Education Lanzhou UniversityLanzhou 730000China National Demonstration Center for Experimental Physics Education Lanzhou UniversityLanzhou 730000China

We review the microwave methods to characterize the material properties, including the established and the emerging techniques in material characterization, especially the permeability spectra of the magnetic thin *** all aspects of the microwave techniques for characterizing the permeability of thin films at microwave frequencies, including the new methods developed by our group, are ***, the introduction part is ***, the coaxial-line with transmission/reflection methods and the pickup coil with electromagnetic induction method are ***, the most widely used shorted microstrip technique is discussed in detail by the equivalent circuit method, transmission line method,and electromagnetic induction ***, the coplanar waveguide method and the near-field probe method are also ***, the high temperature permeability characterization by using the shorted microstrip line, the near-field microwave probe, and the shorted microstrip line probe are described in *** paper may be useful for researchers or engineers who will build up such measurement fixture to make full use of the existing methods or to develop original methods to meet the requirements for ever-rising measurements.

关键词： high frequency permeability coaxial-line methods induction coil method shorted microstrip technique coplanar waveguide method

Noncollinear spintronics and electric-field control:a review

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Rare Metals 2020年第2期39卷 95-112页

作者： Pei-Xin Qin Han Yan Xiao-Ning Wang Ze-Xin Feng Hui-Xin Guo Xiao-Rong Zhou Hao-Jiang Wu Xin Zhang Zhao-Guo-Gang Leng Hong-Yu Chen Zhi-Qi Liu School of Materials Science and Engineering Beihang UniversityBeijing100191China

Our world is composed of various materials with different structures,where spin structures have been playing a pivotal role in spintronic devices of the contemporary information *** from conventional collinear spin materials such as collinear ferromagnets and collinear antiferromagnetic ally coupled materials,noncollinear spintronic materials have emerged as hot spots of research attention due to exotic physical *** this review,we first introduce two types of noncollinear spin structures,i.e.,the chiral spin structure that yields real-space Berry phases and the coplanar noncollinear spin structure that could generate momentum-space Berry phases,and then move to relevant novel physical phenomena including topological Hall effect,anomalous Hall effect,multiferroic,Weyl fermions,spin-polarized current and spin Hall effect without spin-orbit coupling in these noncollinear spin ***,we summarize and elaborate the electric-field control of the noncollinear spin structure and related physical effects,which could enable ultralow power spintronic devices in *** the final outlook part,we emphasize the importance and possible routes for experimentally detecting the intriguing theoretically predicted spin-polarized current,verifying the spin Hall effect in the absence of spin-orbit coupling and exploring the anisotropic magnetoresistance and domain-wall-related magnetoresistance effects for noncollinear antiferromagnetic materials.

关键词： Noncollinear spintronics Chiral spin texture coplanar noncollinear spin texture Electric-field control Spintronic devices

Synthesis,Bioactivity and Crystal Structure Analysis of N-(2-ethoxyphenyl)-3-oxobenzo[d]isothiazole-2(3H)-carboxamide

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Chinese Journal of Structural Chemistry 2012年第5期31卷 758-762页

作者：王向辉杨建新林强 Institute of Environmental Science and Engineering Kunming University of Science and Technology Hainan Provincial Fine Chemical Engineering Center Department of Materials and Chemical EngineeringHainan University Institute of Chemistry and Chemical Engineering Hainan Normal University

The title compound N-（2-ethoxyphenyl）-3-oxobenzo[d]isothiazole-2（3H）-carboxa-mide（C16H14N2O3S,Mr = 314.35） has been synthesized and structurally characterized by IR,1H NMR and single-crystal X-ray *** crystal belongs to triclinic,space group P with a = 4.6395（15）,b = 8.689（3）（A°）, c=17.917（7）（A°）α=87.763（9）,β = 84.625（9）,γ = 82.344（9）°,V = 712.4（4）（A°）^3,Z = 2,Dc = 1.465 Mg·m^-3,λ（MoKa） = 0.71073,F（000） = 328,μ（MoKa） = 0.242 mm-1,the final R = 0.038 and wR = 0.089.A total of 3702 unique reflections were collected,of which 2762 with I 〉 2σ（I） were observed.X-ray analysis revealed that the benzisothiazolone ring and benzene moieties were essentially planar,and three intramolecular hydrogen bonds N（2）-H（2N）…O（1）,N（2）-H（2N）…O（3） and C（10）-H（10）…O（2） were *** preliminary biologi-cal test showed that the title compound had antifungal and antibacteria activities against Bacillus subtilis（CMCC63003）,Aeromonas hydrophila（ATCC7966）,Staphylococcus aureus（ATCC6538）,Escherichia coli（JM103）,Blastomyces albicans,Gloeosporium papaya ***,Colletotrichum gloeosporioides Penz and Botryodiplodia theobromae.

关键词： benzisothiazolone synthesis crystal structure coplanar

Fatigue crack growth investigation on offshore pipelines with three-dimensional interacting cracks

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Geoscience Frontiers 2018年第6期9卷 1689-1697页

作者： Yanmei Zhang Zhongmin Xiao Jun Luo School of Mechanical and Aerospace Engineering Nanyang Technological University Department of Mechanics Huazhong University of Science and Technology

Due to high cost of full-scale experimental setup, this study presents a numerical model on fatigue behaviours of offshore pipeline with multiple coplanar cracks under cyclic tensile loadings. The validation on numerical results is made by other researchers' experimental results, and significant parameters affecting fatigue crack growth are studied.

关键词： coplanar cracks Multiple 3-D cracks XFEM Fatigue crack initiation Fatigue crack growth

Synthesis and Crystal Structure of 4-Oxo-1,2,4-triazino[4,5-a]benzimidazole

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Chinese Journal of Structural Chemistry 2011年第1期30卷 97-100页

作者：王越周庆发林国武狄丽丽陆涛 College of Basic Science China Pharmaceutical University Key Laboratory of Drug Quality Control and Pharmacovigilance(China Pharmaceutical University) Ministry of Education

The title compound 4-oxo-1,2,4-triazino[4,5-a]benzimidazole（C9H6N4O,Mr = 186.18） has been synthesized and structurally characterized by IR,NMR and single-crystal X-ray diffraction. The crystal belongs to monoclinic,space group P21/c,with a = 9.1530（18） ,b = 7.2260（14）,c = 12.604（3） ,β = 106.92（3） ,V = 797.5（3）A^3,Z = 4,Dc = 1.551 g/cm^3,λ（MoKa） = 0.71073,F（000） = 384,μ（MoKa） = 0.109 mm^-1,the final R = 0.0632 and wR = 0.1095. A total of 1444 unique reflections were collected,of which 767 with I 〉 2σ（I） were observed. The structure of the title compound is planar. In packing,the molecules are intersected to each other to form chains along three dimensions,together by intermolecular N-H…O and C-H…N hydrogen bonds. The whole structure is further stabilized by π…π interaction between two adjacent tricyclic ring systems,with the centroid-to-centroid distance of 3.369（4） A.

关键词： benzimidazole triazine synthesis crystal structure coplanar

Ultra-Wideband Log Periodic Dipole Antenna (LPDA) for Wireless Communication Applications

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Journal of Electromagnetic Analysis and Applications 2018年第6期10卷 119-129页

作者： Dalia N. Elsheakh Esmat A. Abdallah Microstrip Department Electronics Research Institute El Dokki Egypt

This paper proposes a printed log-periodic dipole antenna (LPDA) for ultra wide bandwidth (UWB) applications. The antenna comprises of cascading four U shaped elements of different line lengths with balun circuit to improve the antenna impedance matching. The proposed antenna dimensions are 50 × 50 mm2 with FR4 substrate thickness 0.8 mm. Full-wave EM solver HFSS (High Frequency Structure Simulator) is used for modeling the proposed antenna. The pulse distortion is verified by the measured the proposed antenna performance with virtually steady group delay. The simulation and experimental results show that the proposed antenna exhibits good impedance matching, stable radiation patterns throughout the whole operating frequency bands, acceptable gain and stable group delay over the entire operating band. An UWB extended from 1.85 GHz to 11 GHz is obtained, and the average antenna gain is about 5.5 dBi over the operating band with peak gain around 6.5 dBi and 70% average radiation efficiency.

关键词： High Frequency Structure Simulation (HFSS) Dipole Antenna Log Periodic coplanar Waveguide (CPW) Ultra Wideband (UWB) Radiation Pattern Radiation Efficiency Group Delay

On the Quantum Entanglement Reinterpretation Using the Time as Real Instantaneous Signal Field

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Journal of Modern Physics 2017年第6期8卷 853-891页

作者： Elsadig Naseraddeen Founder and General Manager Information Fluxes-FZE Dubai UAE

In relativistic mechanics the time-like vector characterize the motion in spacetime with speed faster than the speed of light in vacuum c in which the line element ds2=c2dt2-dx2-dx2-dz2 is less than zero (where is infinitesimal change in time, and are infinitesimal change in space), thus the time in relativistic mechanics can instantaneously flow [1], however in quantum mechanics although the time is treated as unobservable parameter (without any Hermitian observable operator have engine-value equivalent to time) any two physical quantity described by two non-commuting observable operatorsand fulfill , the knowledge of one immediately produce the knowledge of the other [2], thus in quantum mechanics if two particles interacted in finite temporal epoch and then separated in space the gaining of knowledge by the local measurement of physical quantity runs on one them (for example the measurement of spin direction of one particle using Stern-Gerlach experiment) immediately produce the knowledge of the complementary physical quantity of the other particle (for example the opposite spin direction of the other particle), this simply called quantum entanglement the concept that so much advanced after publication of the Jon Bell’s 1964 celebrated paper [3] in which he illustrated that we can add parameters to quantum mechanics to determine the results of individual measurements, without changing the statistical predictions, and then he conclude “there must be a mechanism whereby the setting of one measuring device can influence the reading of another instrument, however remote. Moreover, the signal involved must propagate instantaneously so that such a theory could not be Lorentz invariant”. The question now what these signals that can propagate instantaneously? The answer in this paper will be the time signals field which is defined for each constituent matter particle M and at each space point P as the measure of the total length of all occupation and leaving epochs of P

关键词： Real-Time State Real-Time Digital State Real-Time Transition State Entanglement Translation Digital Levels Calculus of Fluctuations Fluctuation Tensor Field Collinear Space coplanar Space