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Groove modeling and digital simulation for intersecting structures of circular tubes based on coplanarity of vectors
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作者 Chen Changrong Zhou Sunsheng +3 位作者 Lian Guofu Huang Xu Feng Meiyan Gao Xianfeng 《China Welding》 CAS 2022年第2期29-38,共10页
In order to establish the groove model for intersecting structures of circular tubes,mathematical model of the intersecting line is established by the method of analytic geometry,and parametric equations are thus dete... In order to establish the groove model for intersecting structures of circular tubes,mathematical model of the intersecting line is established by the method of analytic geometry,and parametric equations are thus determined.The dihedral angle,groove angle and actual cutting angle for any position of the intersecting line are derived as well.In order to identify groove vectors for two pipes,a new analytical method,i.e.coplanarity of vectors,is further proposed to complete the groove model.The established model is virtually verified by programming and simulation calculation in the MATLAB environment.The results show that groove vectors of intersecting structures simulated by MATLAB are consistent with the theoretical groove model,indicating that the theoretical groove model established in this paper is accurate,and further proves that the proposed coplanarity of vectors for solving groove vectors is correct and feasible.Finally,a graphical user interface(GUI)is developed by MATLAB software to independently realize functions such as model drawing,variable calculation and data output.The research outcome provides a theoretical foundation for the actual welding of circular intersecting structures,and lays an essential basis for weld bead layout and path planning. 展开更多
关键词 method of analytic geometry in space intersecting line mathematical model coplanarity of vectors groove model MATLAB simulation
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Controlling Morphology of Active Layer by Tuning Coplanarity of the Centrality in Acceptor-Donor-Acceptor Small Molecules for Photovoltaic Application 被引量:2
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作者 Pan Zhang Chao Li Yue Zhao Yaowen Li Yingfeng Tu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第11期1439-1448,共10页
A series of acceptor-donor-acceptor alternative small molecules were synthesized containing electron-donating central building moieties of phenothiazine, 2,7-carbazole and thieno[3,4-b]thiophene and electron-accepting... A series of acceptor-donor-acceptor alternative small molecules were synthesized containing electron-donating central building moieties of phenothiazine, 2,7-carbazole and thieno[3,4-b]thiophene and electron-accepting moie- ties of tetrazine on both sides. The various conformations of the central blocks, with the coplanarity in an order of phenothiazine〈2,7-carbazole〈thieno[3,4-b]thiophene, have an obvious influence on the optical, electrochemical property and the crystallinity of small molecule. In addition, the blend films between small molecule and (6,6)-phenyl-C6rbutyric acid methyl ester offered significantly various morphologies, changing from uniform sur- face to interpenetrated networks. As a result, the bulk heterojunction photovoltaic devices based on the three small molecules provided varied performance, and the highest coplanar molecule based device exhibited the best photo- voltaic performance. 展开更多
关键词 acceptor-donor-acceptor small molecules central blocks coplanarity MORPHOLOGY
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Direct observation of intramolecular coplanarity regulated polymorph emission of a tetraphenylethene derivative
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作者 Qingkai Qi Shan Jiang +5 位作者 Qinglong Qiao Jinbei Wei Bin Xu Xiaocun Lu Zhaochao Xu Wenjing Tian 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第11期2985-2987,共3页
Polymorphism makes it possible to clarify the relationship between emission property and crystal structure.However,based on the exact molecular conformation in tetraphenylethene polymorphisms,it is still challenging t... Polymorphism makes it possible to clarify the relationship between emission property and crystal structure.However,based on the exact molecular conformation in tetraphenylethene polymorphisms,it is still challenging to evaluate the difference of intramolecular coplanarity without the support of calculation because of the complex combination of four different torsion angles between four peripheral benzenes and the central ethylene plane.Here,by using a di-formyl-functionalized tetraphenylethene derivative,two ideal polymorphisms with a consistent trend of the corresponding torsion angles have been obtained.For the first time,we explicitly demonstrated that intramolecular coplanarity is the underlying cause of the polymorphism-dependent emission of tetraphenylethene derivatives. 展开更多
关键词 Tetraphenylethene POLYMORPHISM Intramolecular coplanarity Intermolecular stacking Photophysical property
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Optimize Purcell filter design for reducing influence of fabrication variation
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作者 蔡晓 周翼彪 +2 位作者 于文龙 熊康林 冯加贵 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期589-594,共6页
To protect superconducting qubits and enable rapid readout, optimally designed Purcell filters are essential. To suppress the off-resonant driving of untargeted readout resonators, individual Purcell filters are used ... To protect superconducting qubits and enable rapid readout, optimally designed Purcell filters are essential. To suppress the off-resonant driving of untargeted readout resonators, individual Purcell filters are used for each readout resonator.However, achieving consistent frequency between a readout resonator and a Purcell filter is a significant challenge. A systematic computational analysis is conducted to investigate how fabrication variation affects filter performance, through focusing on the coupling capacitor structure and coplanar waveguide(CPW) transmission line specifications. The results indicate that the T-type enclosing capacitor(EC), which exhibits lower structural sensitivity, is more advantageous for achieving target capacitance than the C-type EC and the interdigital capacitor(IDC). By utilizing a large-sized CPW with the T-type EC structure, fluctuations in the effective coupling strength can be reduced to 10%, given typical micro-nanofabrication variances. The numerical simulations presented in this work minimize the influence of fabrication deviations, thereby significantly improving the reliability of Purcell filter designs. 展开更多
关键词 superconducting circuit Purcell filter coplanar waveguide capacitor structure
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Modulating perovskite crystallization and band alignment using coplanar molecules for high-performance indoor photovoltaics
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作者 Qu Yang Shuhan Fan +5 位作者 Haozhe Zhang Zhenhuang Su Xingyu Gao Hui Shen Mingkui Wang Xiu Gong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期383-390,共8页
The proper bandgap and exceptional photostability enable CsPbI_(3) as a potential candidate for indoor photovoltaics(IPVs),but indoor power conversion efficiency(PCE) is impeded by serious nonradiative recombination s... The proper bandgap and exceptional photostability enable CsPbI_(3) as a potential candidate for indoor photovoltaics(IPVs),but indoor power conversion efficiency(PCE) is impeded by serious nonradiative recombination stemming from challenges in incomplete DMAPbI_(3) conversion and lattice structure distortion.Here,the coplanar symmetric structu re of hexyl sulfide(HS) is employed to functionalize the CsPbI_(3) layer for fabricating highly efficient IPVs.The hydrogen bond between HS and DMAI promotes the conversion of DMAPbI_(3) to CsPbI_(3),while the copianar symmetric structure enhances crystalline order.Simultaneously,surface sulfidation during HS-induced growth results in the in situ formation of PbS,spontaneously creating a CsPbI_(3) N-P homojunction to enhance band alignment and carrier mobility.As a result,the CsPbI_(3)&HS devices achieve an impressive indoor PCE of 39.90%(P_(in):334.6 μW cm^(-2),P_(out):133.5 μW cm^(-2)) under LED@2968 K,1062 lux,and maintain over 90% initial PCE for 800 h at ^(3)0% air ambient humidity. 展开更多
关键词 Perovskite indoor photovoltaics CsPbI_(3) Coplanar symmetric structure molecules Crystallization kinetics Hydrogen bond N-P homojunction
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Phase II Clinical Study of Three-Dimensional Printed Coplanar Template Combined with CT-Guided Percutaneous Core Needle Biopsy of Pulmonary Nodules in Elderly Patients
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作者 Wangti Xie Yu Wu +11 位作者 Xiaoshan Cheng Jianbing Hu Fang Wen Jia Xiao Pan Luo Yuqi Su Xiang Yao Jianlong Fang Grong Dan Xianggan Huang Dunqian Liu Jie Weng 《Journal of Biosciences and Medicines》 2024年第7期325-336,共12页
Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lu... Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lung, brain and blood vessels and cannot tolerate surgery. Computed tomography (CT)-guided percutaneous core needle biopsy (CNB) was the first choice for pathological diagnosis and subsequent targeted drugs, immune drugs or ablation treatment. CT-guided percutaneous CNB requires clinicians with rich CNB experience to ensure high CNB accuracy, but it was easy to cause complications such as pneumothorax and hemorrhage. Three-dimensional (3D) printing coplanar template (PCT) combined with CT-guided percutaneous pulmonary CNB biopsy has been used in clinical practice, but there was no prospective, randomized controlled study. Methods: Elderly patients with lung nodules admitted to the Department of Oncology of our hospital from January 2019 to January 2023 were selected. A total of 225 elderly patients were screened, and 30 patients were included after screening. They were randomly divided into experimental group (Group A: 30 cases) and control group (Group B: 30 cases). Group A was given 3D-PCT combined with CT-guided percutaneous pulmonary CNB biopsy, Group B underwent CT-guided percutaneous pulmonary CNB. The primary outcome measure of this study was the accuracy of diagnostic CNB, and the secondary outcome measures were CNB time, number of CNB needles, number of pathological tissues and complications. Results: The diagnostic accuracy of group A and group B was 96.67% and 76.67%, respectively (P = 0.026). There were statistical differences between group A and group B in average CNB time (P = 0.001), number of CNB (1 vs more than 1, P = 0.029), and pathological tissue obtained by CNB (3 vs 1, P = 0.040). There was no statistical difference in the incidence of pneumothorax and hemorrhage between the two groups (P > 0.05). Conclusions: 3D-PCT combined with CT-guided percutaneous CNB can improve the puncture accuracy of elderly patients, shorten the puncture time, reduce the number of punctures, and increase the amount of puncture pathological tissue, without increasing pneumothorax and hemorrhage complications. We look forward to verifying this in a phase III randomized controlled clinical study. . 展开更多
关键词 Pulmonary Nodules Elderly patients Three-Dimensional (3D) Printed Coplanar Template (PCT) Core Needle Biopsy (CNB) Computed Tomography (CT)
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Low-Microwave Loss Coplanar Waveguides Fabricated on High-Resistivity Silicon Substrate 被引量:1
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作者 杨华 朱洪亮 +3 位作者 谢红云 赵玲娟 周帆 王圩 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第1期1-4,共4页
Three kinds of coplanar waveguides (CPWs) are designed and fabricated on different silicon substrates---common low-resistivity silicon substrate (LRS), LRS with a 3μm-thick silicon oxide interlayer, and high-resi... Three kinds of coplanar waveguides (CPWs) are designed and fabricated on different silicon substrates---common low-resistivity silicon substrate (LRS), LRS with a 3μm-thick silicon oxide interlayer, and high-resistivity silicon (HRS) substrate. The results show that the microwave loss of a CPW on LRS is too high to be used, but it can be greatly reduced by adding a thick interlayer of silicon oxide between the CPW transmission lines and the LRS.A CPW directly on HRS shows a loss lower than 2dB/cm in the range of 0-26GHz and the process is simple,so HRS is a more suitable CPW substrate. 展开更多
关键词 coplanar waveguides high-resistivity silicon microwave loss high frequency optoelectronic packaging
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A Machine Vision System for Ball Grid Array Package Inspection
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作者 夏年炯 曹其新 李杰 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期139-142,共4页
An optical inspection method of the Ball Grid Array package(BGA) was proposed by using a machine vision system. The developed machine vision system could get main critical factors for BGA quality evaluation, such as t... An optical inspection method of the Ball Grid Array package(BGA) was proposed by using a machine vision system. The developed machine vision system could get main critical factors for BGA quality evaluation, such as the height of solder ball, diameter, pitch and coplanarity. The experiment has proved that this system is available for BGA failure detection. 展开更多
关键词 ball gird array machine vision system coplanarity image processing
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Ultra-wideband bilateral tapered slot-line antenna fed by coplanar waveguide 被引量:1
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作者 章朋 章文勋 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期128-131,共4页
In order to broaden the bandwidth of a tapered slot- line antenna (TSA), a bilateral tapered slot-line antenna (BTSA) with a new feeding structure of coplanar waveguide (CPW) is developed. Based on the fact that... In order to broaden the bandwidth of a tapered slot- line antenna (TSA), a bilateral tapered slot-line antenna (BTSA) with a new feeding structure of coplanar waveguide (CPW) is developed. Based on the fact that the bandwidth limitation of TSA mainly depends on its feeding structure, an improved CPW-based feed structure etched on the backboard of the BTSA is adopted to perform traveling-wave transition. Both the simulation results and measurement data verify that the proposed feeding structure results in "high-pass" frequency response for antenna impedance matching. The voltage standing wave ratio (VSWR) is less than 2:1 when the frequency is higher than 3 GHz. The antenna gain exceeds 7 dBi with good radiation patterns when the bandwidth is from 4 to 16 GHz. This ultra wideband (UWB) antenna with a compact size is specially available for the electronic systems of counter-measure and microwave imaging. 展开更多
关键词 ultra wideband (UWB) tapered slot-line antenna(TSA) feeding structure coplanar waveguide (CPW)
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基于U形槽陷波的共面波导超宽带天线 被引量:3
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作者 纪涛 卢新栋 《航空兵器》 2014年第1期21-25,共5页
针对超宽带系统易受IEEE802.11a无线局域网(WLAN)的干扰问题,提出了带有U形槽的平面超宽带天线。该天线采用共面波导馈电,并在波导馈线处刻蚀一U形槽实现5.1~5.9 GHz的陷波。仿真结果表明,在2.7~12 GHz的范围内,该天线阻抗... 针对超宽带系统易受IEEE802.11a无线局域网(WLAN)的干扰问题,提出了带有U形槽的平面超宽带天线。该天线采用共面波导馈电,并在波导馈线处刻蚀一U形槽实现5.1~5.9 GHz的陷波。仿真结果表明,在2.7~12 GHz的范围内,该天线阻抗带宽为9.3 GHz(126%),带宽内具有良好的阻抗特性和全向辐射特性,并且在5.1~5.9 GHz频带内具有明显的陷波特性,能够有效地抑制 WLAN之间的干扰,是一种性能较好,易于集成,有实用价值的陷波超宽带天线。 展开更多
关键词 超宽带(UWB)天线 陷波特性 共面波导(CPW) U形槽 COPLANAR waveguide (CPW)
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High speed robust image registration and localization using optimized algorithm and its performances evaluation 被引量:13
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作者 Meng An Zhiguo Jiang Danpei Zhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期520-526,共7页
Local invariant algorithm applied in downward-looking image registration,usually computes the camera's pose relative to visual landmarks.Generally,there are three requirements in the process of image registration whe... Local invariant algorithm applied in downward-looking image registration,usually computes the camera's pose relative to visual landmarks.Generally,there are three requirements in the process of image registration when using these approaches.First,the algorithm is apt to be influenced by illumination.Second,algorithm should have less computational complexity.Third,the depth information of images needs to be estimated without other sensors.This paper investigates a famous local invariant feature named speeded up robust feature(SURF),and proposes a highspeed and robust image registration and localization algorithm based on it.With supports from feature tracking and pose estimation methods,the proposed algorithm can compute camera poses under different conditions of scale,viewpoint and rotation so as to precisely localize object's position.At last,the study makes registration experiment by scale invariant feature transform(SIFT),SURF and the proposed algorithm,and designs a method to evaluate their performances.Furthermore,this study makes object retrieval test on remote sensing video.For there is big deformation on remote sensing frames,the registration algorithm absorbs the Kanade-Lucas-Tomasi(KLT) 3-D coplanar calibration feature tracker methods,which can localize interesting targets precisely and efficiently.The experimental results prove that the proposed method has a higher localization speed and lower localization error rate than traditional visual simultaneous localization and mapping(vSLAM) in a period of time. 展开更多
关键词 local invariant features speeded up robust feature(SURF) Harris corner Kanada-Lucas-Tomasi(KLT) transform Coplanar camera calibration algorithm landmarks.
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Synthesis,Bioactivity and Crystal Structure Analysis of N-(2-ethoxyphenyl)-3-oxobenzo[d]isothiazole-2(3H)-carboxamide 被引量:8
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作者 王向辉 杨建新 林强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第5期758-762,共5页
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 diffraction.Th... 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 diffraction.The 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 observed.The 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 P.Henn,Colletotrichum gloeosporioides Penz and Botryodiplodia theobromae. 展开更多
关键词 benzisothiazolone SYNTHESIS crystal structure COPLANAR
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Mechanical response and microscopic damage mechanism of pre-flawed sandstone subjected to monotonic and multilevel cyclic loading:A laboratory-scale investigation 被引量:7
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作者 Kesheng Li Shengqi Yang +3 位作者 Chuanxiao Liu Yun Chen Guanglei Zhang Qing Ma 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第12期1487-1510,共24页
This study aims to investigate the mechanical response and acoustic emission(AE)characteristic of pre-flawed sandstone under both monotonic and multilevel constant-amplitude cyclic loads.Specifically,we explored how c... This study aims to investigate the mechanical response and acoustic emission(AE)characteristic of pre-flawed sandstone under both monotonic and multilevel constant-amplitude cyclic loads.Specifically,we explored how coplanar flaw angle and load type impact the strength and deformation behavior and microscopic damage mechanism.Results indicated that being fluctuated before rising with increasing fissure angle under monotonic loading,the peak strength of the specimen first increased slowly and then steeply under cyclic loading.The effect of multilevel cyclic loading on the mechanical parameters was more significant.For a single fatigue stage,the specimen underwent greater deformation in early cycles,which subsequently stabilized.Similar variation pattern was also reflected by AE count/energy/b-value.Crack behaviors were dominated by the fissure angle and load type and medium-scale crack accounted for 74.83%–86.44%of total crack.Compared with monotonic loading,crack distribution of specimen under cyclic loading was more complicated.Meanwhile,a simple model was proposed to describe the damage evolution of sandstone under cyclic loading.Finally,SEM images revealed that the microstructures at the fracture were mainly composed of intergranular fracture,and percentage of transgranular fracture jumped under cyclic loading due to the rapid release of elastic energy caused by high loading rate. 展开更多
关键词 SANDSTONE Pre-existing coplanar flaws Multilevel constant-amplitude cyclic loading Mechanical behavior Microscopic damage mechanism
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TRANSIENT RESPONSE OF A PIEZOELECTRIC CERAMIC WITH TWO COPLANAR CRACKS UNDER ELECTROMECHANICAL IMPACT 被引量:4
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作者 陈增涛 余寿文 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1999年第4期325-333,共9页
The transient response of two coplanar cracks in a piezoelectric ceramic under antiplane mechanical and inplane electric impacting loads is investigated in the present paper. Laplace and Fourier transforms are used to... The transient response of two coplanar cracks in a piezoelectric ceramic under antiplane mechanical and inplane electric impacting loads is investigated in the present paper. Laplace and Fourier transforms are used to reduce the mixed boundary value problems to Cauchy-type singular integral equations in Laplace transform domain, which are solved numerically. The dynamic stress and electric displacement factors are obtained as the functions of time and geometry parameters. The present study shows that the presence of the dynamic electric field will impede or enhance the propagation of the crack in piezoelectric ceramics at different stages of the dynamic electromechanical load. Moreover, the electromechanical response is greatly affected by the ratio of the space of the cracks and the crack length. 展开更多
关键词 piezoelectric ceramic FRACTURE DYNAMICS coplanar crack stress intensity factor integral transform singular integral equation
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Characterization and Modeling of Finite-Ground Coplanar Waveguides in 0.13μm CMOS
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作者 陈勖 王志功 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第6期982-987,共6页
We discuss the characterization and modeling of coplanar waveguides (CPW) realized in TSMC 0. 13μm CMOS process. EM-field simulations with momentum are performed to estimate the important parameters of the transmis... We discuss the characterization and modeling of coplanar waveguides (CPW) realized in TSMC 0. 13μm CMOS process. EM-field simulations with momentum are performed to estimate the important parameters of the transmission lines, such as characteristic impedance and propagation loss. Coplanar waveguide libraries are designed with Z values of 30,50,70, and 100Ω. Finally, the propagation constant and the characteristic impedance are measured in a frequency range from 0. 1 to 40GHz with a vector-network analyzer,using the short-open-loadthru (SOLT) de-embedding technique. The distributed parameters of the CPWs are extracted from the measured S-parameters. 展开更多
关键词 coplanar waveguide CMOS S-PARAMETER
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Fatigue crack growth investigation on offshore pipelines with three-dimensional interacting cracks 被引量:2
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作者 Yanmei Zhang Zhongmin Xiao Jun Luo 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第6期1689-1697,共9页
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 numeri... 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. 展开更多
关键词 COPLANAR cracks Multiple 3-D cracks XFEM FATIGUE CRACK INITIATION FATIGUE CRACK growth
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Quintuple Band Antenna for Wireless Applications with Small Form Factor 被引量:2
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作者 Amir Haider Tayyaba Khan +2 位作者 MuhibUr Rahman Byung Moo Lee Hyung Seok Kim 《Computers, Materials & Continua》 SCIE EI 2021年第3期2241-2251,共11页
A coplanar waveguide-fed quintuple band antenna with a slotted circular-shaped radiator for wireless applications with a high isolation between adjacent bands is presented in this paper.The proposed antenna resonates ... A coplanar waveguide-fed quintuple band antenna with a slotted circular-shaped radiator for wireless applications with a high isolation between adjacent bands is presented in this paper.The proposed antenna resonates at multiple frequencies with corresponding center frequencies of 2.35,4.92,5.75,6.52,and 8.46 GHz.The intended functionality is achieved by introducing a circular disc radiator with five slots and a U-shaped slot in the feed.The proposed antenna exhibits coverage of the maximum set of wireless applications,such as satellite communication,worldwide interoperability for microwave access,wireless local area network(WLAN),long-distance radio telecommunications,and X-band/Satcom wireless applications.The simulation and measurement results of the proposed fabricated antenna demonstrate the high isolation between adjacent bands.A stable realized gain with an advantageous radiation pattern is achieved at the operating frequency bands.The proposed simple design,compact structure,and simple feeding technique make this antenna suitable for integration in several wireless communication applications,where the portability of devices is a significant concern.The proposed antenna is anticipated to be an appropriate candidate for WLAN,long-term evolution,and fifth-generation mobile communication because of its multi-operational bands and compact size for handheld devices. 展开更多
关键词 Coplanar waveguide isolated adjacent bands SATELLITE WIMAX WLAN 5G communication
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Ultra-wideband printed antennas for communication applications 被引量:2
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作者 钟顺时 梁仙灵 +2 位作者 姚风薇 汪伟 白晓峰 《Journal of Shanghai University(English Edition)》 CAS 2006年第1期48-52,共5页
A new type of ultra-wideband (UWB) printed monopole antennas is presented, which is composed of a circular or armular patch and a trapeziform ground plane with a tapered CPW feeder in the middle. Both simulated and ... A new type of ultra-wideband (UWB) printed monopole antennas is presented, which is composed of a circular or armular patch and a trapeziform ground plane with a tapered CPW feeder in the middle. Both simulated and experimental results are presented, showing good agreement and therefore verifying validity of the design. The proposed antenna with a circular monopole patch achieves an 11.6: 1 measured ratio bandwidth of VSWR ≤2 ( from 0,79 GHz to 9.16 GHz), while that with an annular patch obtains a measured ratio impedance bandwidth of 10.6:1 (from 0.87 GHz to 9.47 GHz). In addition, these designs exhibit nearly omnidirectional radiation patterns with simple compact structures, which axe attractive in communications and others UWB applications. 展开更多
关键词 ULTRA-WIDEBAND printed antenna monopole antenna coplanar waveguide.
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Fatigue Investigations on Steel Pipeline Containing 3D Coplanar and Non-Coplanar Cracks 被引量:2
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作者 Zhongmin Xiao Wengang Zhang +1 位作者 Yanmei Zhang Mu Fan 《Computers, Materials & Continua》 SCIE EI 2020年第1期267-280,共14页
Fluctuated loadings from currents,waves and sea ground motions are observed on offshore steel pipelines,and they will result in small cracks to propagate continuously and cause unexpected damage to offshore/geotechnic... Fluctuated loadings from currents,waves and sea ground motions are observed on offshore steel pipelines,and they will result in small cracks to propagate continuously and cause unexpected damage to offshore/geotechnical infrastructures.In spite of the availability of efficient techniques and high-power computers for solving crack problems,investigations on the fatigue life of offshore pipelines with 3D interacting cracks are still rarely found in open literature.In the current study,systematic numerical investigations are performed on fatigue crack growth behaviours of offshore pipelines containing coplanar and non-coplanar cracks.Extended finite element method(XFEM)is adopted to simulate the fatigue crack growth.The qualitative validations of numerical results are made for certain cases with available experimental results.Parametric studies are conducted to investigate the influences of various important parameters on fatigue crack growth.The results will be helpful to assess the fatigue behaviours of steel pipeline with 3D interacting cracks. 展开更多
关键词 Fatigue crack growth steel pipeline coplanar cracks non-coplanar cracks XFEM
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Dosimetric Study of Coplanar and Non-Coplanar Intensity-Modulated Radiation Therapy Planning for Esophageal Carcinoma 被引量:2
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作者 Ying Li Bing Liu +4 位作者 Fushan Zhai Yongfeng Yang Ming Liu Chaoen Bao Qingxiang Zhou 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2013年第4期133-138,共6页
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, fifte... 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. 展开更多
关键词 ESOPHAGEAL CARCINOMA COPLANAR IMRT Non-Coplanar IMRT
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