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Composition and structure design of three-layered composite phosphors for high color rendering chip-on-board light-emitting diode devices 被引量:9
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作者 Xin LIU Xinglu QIAN +6 位作者 Peng ZHENG Xiaopu CHEN Yagang FENG Yun SHI Jun ZOU Rongjun XIE Jiang LI 《Journal of Advanced Ceramics》 SCIE CAS CSCD 2021年第4期729-740,共12页
A three-layered phosphor structure was designed and prepared by the spin coating of BaSi_(2)N_(2)O_(2):Eu(cyan-emitting)and(Sr,Ca)AlSiN_(3):Eu(red-emitting)phosphor films on the yellowemitting Y_(3)Al_(5)O_(12):Ce(YAG... A three-layered phosphor structure was designed and prepared by the spin coating of BaSi_(2)N_(2)O_(2):Eu(cyan-emitting)and(Sr,Ca)AlSiN_(3):Eu(red-emitting)phosphor films on the yellowemitting Y_(3)Al_(5)O_(12):Ce(YAG:Ce)phosphor ceramic synthesized by the solid-state reaction under vacuum sintering.In order to achieve high color rendering lighting,the influence of the composition and structure of the three-layered phosphors on the optical,thermal,and electrical properties of the chip-on-board(COB)packaged white-light-emitting diodes(WLEDs)was studied systematically.The WLED with the structure of“red+cyan+yellow”(R+C+Y)three-layered phosphor generated neutral white light and had a luminous efficacy of 75 lm/W,the fidelity index(R_(f))of 93,the gamut index(R_(g))of 97,and the correlated color temperature(CCT)of 3852 K.Under the excitation of laser diode(LD),the layer-structured phosphor yielded the white light with a luminous efficacy of 120 lm/W,color rendering index(CRI)of 90,and CCT of 5988 K.The result indicates that the three-layered phosphor structure is a promising candidate to achieve high color rendering and high luminous efficacy lighting. 展开更多
关键词 three-layered composite phosphor structure design high color rendering luminous efficacy
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Three-dimensional acoustic radiation force of a eukaryotic cell arbitrarily positioned in a Gaussian beam 被引量:1
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作者 Shuyuan Li Xiaofeng Zhang 《Nanotechnology and Precision Engineering》 CAS CSCD 2023年第1期40-46,共7页
Expressions are derived for calculating the three-dimensional acoustic radiation force(ARF)on a multilayer microsphere positioned arbitrarily in a Gaussian beam.A theoretical model of a three-layer microsphere with a ... Expressions are derived for calculating the three-dimensional acoustic radiation force(ARF)on a multilayer microsphere positioned arbitrarily in a Gaussian beam.A theoretical model of a three-layer microsphere with a cell membrane,cytoplasm,and nucleus is established to study how particle geometry and position affect the three-dimensional ARF,and its results agree well with finite-element numerical results.The microsphere can be moved relative to the beam axis by changing its structure and position in the beam,and the axial ARF increases with increasing outer-shell thickness and core size.This study offers a theoretical foundation for selecting suitable parameters for manipulating a three-layer microsphere in a Gaussian beam. 展开更多
关键词 Off-axis Gaussian beam Acoustic radiation force three-layered microsphere Finite element method
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Analytical analysis of inclined three-layered composite channel with cobalt ferrite nanoparticles and Hall current in Darcy medium
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作者 P.V.Ananth Subray B.N.Hanumagowda +4 位作者 C.S.K.Raju S.V.K.Varma Prakash Jagdish Se-Jin Yook Nehad Ali Shah 《Propulsion and Power Research》 SCIE 2023年第4期523-538,共16页
The present study explores the influence of electromagnetic effects on the flow of a nanofluid in a saturated permeable medium,confined between a clear viscous fluid in an inclined channel.The nanofluid consists of co... The present study explores the influence of electromagnetic effects on the flow of a nanofluid in a saturated permeable medium,confined between a clear viscous fluid in an inclined channel.The nanofluid consists of cobalt ferrite nanoparticles dispersed in ethylene glycol.The governing equations are derived considering Darcy's law for the permeable medium and Tiwari's model for fluids containing nano-sized particles.Additionally,radiation and dissipation effects are incorporated into the energy equation.The equations are transformed into dimensionless form and solved analytically using the perturbation technique.The results are analyzed through graphs and tables for different material parameters.The findings reveal that higher electric and magnetic strengths have a significant impact on the fluid velocity at the interface of the two fluids,resulting in reduced shear both at the clear fluid surface and the interface between them.This highlights the crucial role played by electric and magnetic strengths in modifying flow phenomena.Consequently,combining electric and magnetic strengths with nanofluids can be utilized to achieve desired qualities in multi-fluid flow and enhance heat transfer characteristics. 展开更多
关键词 three-layered flow Inclined composite channel Electromagnetic field NANOFLUID Porous region
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Two-and Three-Layered Dissolving Microneedles for Transcutaneous Delivery of Model Vaccine Antigen in Rats
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作者 Asuka Ikejiri Yukako Ito +1 位作者 Seishiro Naito Kanji Takada 《Journal of Biomaterials and Nanobiotechnology》 2012年第3期325-334,共10页
Purpose: Comparison of transcutaneous immunization of ovalbumin (OA) between two-and three-layered dissolving microneedles (MN) in rats. Methods: We prepared 500 μm long two-layered and three-layered dissolving micro... Purpose: Comparison of transcutaneous immunization of ovalbumin (OA) between two-and three-layered dissolving microneedles (MN) in rats. Methods: We prepared 500 μm long two-layered and three-layered dissolving microneedle (2-MN and 3-MN, respectively) arrays from chondroitin sulfate as the base, and OA as the model antigen. The 2-MN containing OA at the acral portion and 3-MN with OA at the second portion were administered to rat skin transcutaneously. As a positive control, OA solution was injected subcutaneously (sc). The OA delivery and diffusion in the rat skin were studied using confocal microscopy with fluorescein-conjugated OA (FL-OA). Results: The formulated positions of OA were 0-155 ± 5 μm for 2-MN and 175 ± 4 – 225 ± 5 μm for 3-MN. The administered doses of OA were 2.2 ± 0.1 μg, 12.0 ± 0.2 μg and 22.0 ± 0.2 μg for 2-MN, 1.8 ± 0.2 μg, 12.6 ± 0.7 μg, and 20.4 ± 0.3 μg for 3-MN, 10 μg, 100 μg and 1000 μg for sc injection. At 4 weeks after the first administration, 3-MN showed about 2.5-7.0 fold and 5.4 fold higher total Ig (G + A + M) antibody than 2-MN and sc injection of the OA solution. Conclusions: The 3-MN, which delivered OA to the epidermis, is a useful drug delivery system for transcutaneous antigen delivery. 展开更多
关键词 DISSOLVING MICRONEEDLES (Mns) Two-layered MNS three-layered MNS TRANSCUTANEOUS Vaccine OVALBUMIN Fl-Ovalbumin (Fl-Oa)
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Modulation of Fano resonances in symmetry-broken gold-SiO_2-gold nanotube dimers 被引量:2
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作者 WU DaJian YU HaiQun +2 位作者 JIANG ShuMin WU XueWei LIU XiaoJun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第6期1063-1067,共5页
Fano resonances in the symmetry-broken gold-SiO2-gold(BGSG)nanotubes and the associated dimers have been investigated based on the finite element method.In the BGSG nanotube,the symmetry breaking induced the interacti... Fano resonances in the symmetry-broken gold-SiO2-gold(BGSG)nanotubes and the associated dimers have been investigated based on the finite element method.In the BGSG nanotube,the symmetry breaking induced the interactions of the inner gold core and outer gold nanoshell plasmons of all multipolar orders and hence the red-shifts of the plasmon resonance modes and the enhanced quadrupole mode peaks were observed.The interference of the quadrupole mode peak with the subradiant dipole mode caused a Fano-dip in the scattering spectrum.By increasing the core offset-value in the BGSG nanotube,the Fano dip with low energy showed a red-shift and became deeper.Unexpectedly the plasmon coupling between a GSG nanotube and a BGSG nanotube can lead to two strong Fano dips in the scattering spectra of the dimer.It was further noted that the thin side of the BGSG nanotube located at two sides of the dimer gap can lead to the strong near-field coupling between two BGSG nanotubes and hence a deeper and broader Fano dip. 展开更多
关键词 Fano resonance three-layered gold nanotube DIMER finite element methods
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A Three-layered Contrasting Analysis of the Theme in Once more to the lake
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作者 杨晶 《海外英语》 2017年第13期163-165,共3页
Once more to the lake is a representative work of the American Writer, Elwyn Brooks White, and has been acclaimed by people in the world. The paper offers a three-layered contrasting analysis of the essay. By detailed... Once more to the lake is a representative work of the American Writer, Elwyn Brooks White, and has been acclaimed by people in the world. The paper offers a three-layered contrasting analysis of the essay. By detailed analysis of the contrasts running through the whole essay, the author finds that those contrasts are symbol of White's internal struggle and reflection for life.On the foundation of the three-layered contrasts, the paper presents the theme analysis and clarifies the content of the essay. 展开更多
关键词 three-layered contrasting analysis White Once more to the lake
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The westward intrusion of south Pacific water at the western tip of the New Guinea Island
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作者 KIM Eung JEON Dongchull Hadikusumah 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第1期24-31,共8页
From the eastern Indonesian cruise from November 14 to 23, 2007, CTD (conductivity, temperature, depth profiler)/ADCP (acoustic Doppler current profiler)casting and seawater sampling were done at 25 stations aroun... From the eastern Indonesian cruise from November 14 to 23, 2007, CTD (conductivity, temperature, depth profiler)/ADCP (acoustic Doppler current profiler)casting and seawater sampling were done at 25 stations around Waigeo Island near New Guinea Island. It was found overall westward intrusion of the south Pacific waters into the Seram Sea and southward spreading of the north and south Pacific waters into the Seram Sea. There is westward residual flow along the channel between Waigeo and New Guinea within upper 200 m with the maximum speed up to 50 cm/s, and much weaker eastward flow in the lower layer (〈 10 cm/s) due to blocking by the shallow sill at the west of the Dampier Strait. The abrupt change of bottom topography induces active horizontal and vertical mixing which results in a three-layered current system with a major through-flow of-0.99 Sv (Sv = 106 ma/s) into the Seram Sea; the transports in the upper and the lower layers are -1.14 Sv and -0.24 Sv (westward), respectively, and in the middle there is a return flow with the transoort of +0.39 Sv (eastward). 展开更多
关键词 a three-layered system New Guinea coastal undercurrent south Pacific tropical water (SPTW) south Pacific intermediate water (SP1W) vertical mixing
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Vibration of Three-Layered FGM Cylindrical Shells with Middle Layer of Isotropic Material for Various Boundary Conditions
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作者 Muhammad Nawaz Naeem Awais Gul Khan +2 位作者 Shahid Hussain Arshad Abdul Ghafar Shah Madiha Gamkhar 《World Journal of Mechanics》 2014年第11期315-331,共17页
In the present study, vibration analysis of a three-layered cylindrical shell is performed whose inner and outer layers are composed of functionally graded materials whereas the middle one is assumed to be of isotropi... In the present study, vibration analysis of a three-layered cylindrical shell is performed whose inner and outer layers are composed of functionally graded materials whereas the middle one is assumed to be of isotropic material. This formation of a cylindrical shell influences stiffness modulii and the resultant material properties. The shell problem is formulated from the constitutive relations of stresses and strains with the displacement deformations and they are taken from Love’s thin shell theory. This problem is transformed into the integral form by evaluating the expressions for the strain and kinetic energies of the shell. Rayleigh-Ritz method is employed to solve the shell dynamic equations. Vibration characteristics of these cylindrical shells are investigated for a number of physical parameters and configurations of the fabrication of shells. The axial modal dependence is approximated by the characteristic beam functions that satisfy the boundary conditions. Results evaluated, show good agreement with the open literature. 展开更多
关键词 Functionally Graded MATERIAL ISOTROPIC MATERIAL three-layered Cylindrical SHELL Love’s Thin SHELL Theory Rayleigh-Ritz Method Natural Frequency
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Study on Three-layered Grid Conceptual Prototype Using Ecological Network Computing Environment
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作者 皋磊 丁永生 任立红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期8-11,共4页
Next generation grid systems where the emphasis shifts to distributed global collaboration, a service-oriented approach and information layer issues exhibit a strong sense of automation. Requirements for these systems... Next generation grid systems where the emphasis shifts to distributed global collaboration, a service-oriented approach and information layer issues exhibit a strong sense of automation. Requirements for these systems resemble the self-organizing and the healing properties of natural ecosystems. Some key ecological concepts and mechanisms are introduced into the design for the third generation grid computing architectures by inspiration of this resemblance. Also, an Ecological Network-based Computing Environment (ENCE) platform is designed in this paper. Based on the ENCE platform, a grid-computing model of three-layered grid conceptual prototype that embeds the ENCE layers is presented from the viewpoint of implementation. The implementation model should be useful to the design of the third generation grid systems. 展开更多
关键词 ecological network ECOSYSTEM grid system automation EMERGENCE three-layered grid conceptual prototype
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核心素养如何落地:从横向分类到水平分层的转向 被引量:70
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作者 钟柏昌 李艺 《华东师范大学学报(教育科学版)》 CSSCI 北大核心 2018年第1期55-63,共9页
借助"学生发展核心素养"和"学科核心素养","核心素养"已成指导我国教育改革的风向标。尽管如此,对其本质的追问依然不足。必须认识到,从整体发展和终身发展角度而言,核心素养的本质是关于教育目标的重新... 借助"学生发展核心素养"和"学科核心素养","核心素养"已成指导我国教育改革的风向标。尽管如此,对其本质的追问依然不足。必须认识到,从整体发展和终身发展角度而言,核心素养的本质是关于教育目标的重新理解,是把握教育目标的一种方式。建议采用分层结构来诠释"核心素养",在维护人的终身发展和完整发展方面,可以实现从教育理想到教育实践的贯通。 展开更多
关键词 核心素养 教育目标 三层结构
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基于.NET框架的Web应用设计与实现 被引量:13
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作者 庞开放 李龙澍 《微机发展》 2005年第3期85-89,共5页
微软.NET平台是一个建立和开发各种Web应用的主流平台。文中介绍了如何利用.NET平台开发高效、简洁的Web应用程序。首先给出了模式,MVC,Three-LayeredServicesApplication模式和XMLWebService架构,然后运用这些模式和XMLWebService架构... 微软.NET平台是一个建立和开发各种Web应用的主流平台。文中介绍了如何利用.NET平台开发高效、简洁的Web应用程序。首先给出了模式,MVC,Three-LayeredServicesApplication模式和XMLWebService架构,然后运用这些模式和XMLWebService架构,结合采购管理ERP子系统的实例,讨论了在Microsoft.NET框架下的研究与应用。系统很好地实现了业务处理与客户交互的分离,实现了异构数据源间的互相通信,使得构建的Web应用程序具有较好的可重用性、健壮性和较高的实用价值。 展开更多
关键词 模式 MVC 三层服务应用程序 XML WEB服务 .NET框架
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科技资源共享价值最大化的三层次模型(VAA) 被引量:16
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作者 董诚 侯敏 《科技管理研究》 CSSCI 北大核心 2013年第11期231-234,共4页
如何实现科技资源全生命周期价值最大化是科技资源共享系统设计的目标和尚未解决的难题,为此,提出科技资源是各种价值的集合体,科技资源共享是促进价值转换、传递的过程,科技资源共享是价值共享等观点。在此基础上,提出包括可见性、可... 如何实现科技资源全生命周期价值最大化是科技资源共享系统设计的目标和尚未解决的难题,为此,提出科技资源是各种价值的集合体,科技资源共享是促进价值转换、传递的过程,科技资源共享是价值共享等观点。在此基础上,提出包括可见性、可及性、可用性三个层次的科技资源共享价值最大化三层次模型,并结合国家科技基础条件平台建设对三个层次进行了细化分析。 展开更多
关键词 科技政策 共享三层次模型 科技资源 科技资源共享 科技资源价值 国家科技基础条件平台 信息资源
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三层粗糙面电磁散射的矩量法研究 被引量:12
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作者 张连波 郭立新 +1 位作者 苟雪银 王安琪 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2013年第6期147-154,共8页
应用矩量法、采用脉冲基函数结合点匹配技术研究了三层粗糙面的电磁散射特性,给出了积分方程、阻抗矩阵元素表达式及散射系数的定义式.利用蒙特卡罗方法模拟了用高斯粗糙面近似代替实际复杂的粗糙面,通过与时域有限差分方法计算结果的对... 应用矩量法、采用脉冲基函数结合点匹配技术研究了三层粗糙面的电磁散射特性,给出了积分方程、阻抗矩阵元素表达式及散射系数的定义式.利用蒙特卡罗方法模拟了用高斯粗糙面近似代替实际复杂的粗糙面,通过与时域有限差分方法计算结果的对比,说明该方法的正确性.将所研究的三层粗糙面散射模型退化成单层粗糙面散射模型,与已有的单层粗糙面散射模型计算结果进行对比,说明所给方法的通用性.最后讨论了入射角、介电常数、均方根高度、相关长度和每层粗糙面的厚度对三层粗糙面双站散射系数的影响. 展开更多
关键词 矩量法 三层粗糙面 电磁散射
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三层介质光纤包层模色散方程及包层HE/EH模 被引量:3
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作者 张自嘉 施文康 吉小军 《光电子.激光》 EI CAS CSCD 北大核心 2003年第5期501-504,共4页
利用解析法研究了Tsao和Erdogan关于3层介质光纤模型的包层模色散方程,对2个色散方程的等价性给出了证明。在研究长周期光纤光栅(LPFG)中,对传播常数的计算应选用Tsao给出的方程,在计算与场方程有关的量时应选用Erdogan的方程。计算了... 利用解析法研究了Tsao和Erdogan关于3层介质光纤模型的包层模色散方程,对2个色散方程的等价性给出了证明。在研究长周期光纤光栅(LPFG)中,对传播常数的计算应选用Tsao给出的方程,在计算与场方程有关的量时应选用Erdogan的方程。计算了部分包层模的传播常数,给出了区分包层HE/EH模的方法。 展开更多
关键词 3层介质光纤 包层模 色散方程 HE/EH模 长周期光纤光栅 LPFG
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印度南亚援助政策的理念、实践与趋势:从“古杰拉尔主义”到“莫迪主义” 被引量:12
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作者 戴永红 张婷 《南亚研究》 CSSCI 2019年第3期73-105,153-154,共35页
南亚地区始终是印度外交政策的优先方向,印度对外援助政策也主要集中于南亚国家及地区。冷战期间,印度的南亚外交政策目标在于建立和确保其在南亚的主导地位,其南亚援助政策带有强烈的霸权色彩。冷战后,印度的南亚外交政策开始在确保南... 南亚地区始终是印度外交政策的优先方向,印度对外援助政策也主要集中于南亚国家及地区。冷战期间,印度的南亚外交政策目标在于建立和确保其在南亚的主导地位,其南亚援助政策带有强烈的霸权色彩。冷战后,印度的南亚外交政策开始在确保南亚主导地位的前提下,推行改善与邻国关系的睦邻政策,即“古杰拉尔主义”,秉持着“睦邻友好,不求相应回报”的理念,其南亚援助政策也开始面向更大范围的南亚邻国。莫迪政府执政以来外交政策更为积极,更加注重地区外交政策,坚持“印度第一,邻国优先”的理念,形成了带有亲和色彩的“莫迪主义”,其南亚援助政策更积极有为。随着印度南亚外交政策理念的发展变化,印度的南亚援助有了多元化的趋势,逐渐形成了一个以“三圈层式”的双边援助为中心,辅之以南亚区域多边援助为支点的周边对外援助模型。印度2019年大选尘埃落定,新一任政府的南亚政策是否会有所变化,南亚援助政策是否会受到影响,未来印度南亚援助政策的发展新方向会是什么,值得我们思考。因此,总结分析冷战后印度南亚援助政策的变化,有利于我们更好地窥见印度南亚政策的利益关联,更好地推动“一带一路”在南亚的开展。 展开更多
关键词 印度 南亚援助政策 莫迪主义 “一带一路” “三圈层式”援助
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基本公共服务均等化辨析 被引量:11
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作者 刘明德 《上海行政学院学报》 CSSCI 北大核心 2017年第4期71-82,共12页
基本公共服务均等化是政府的重要施政目标,也为学术界视为理所当然的发展方向。然而,目前对"基本公共服务"以及"均等化"这两个概念的使用存在问题,致使相关文件对基本公共服务体系的论述不够精当。而且,城乡(区域之... 基本公共服务均等化是政府的重要施政目标,也为学术界视为理所当然的发展方向。然而,目前对"基本公共服务"以及"均等化"这两个概念的使用存在问题,致使相关文件对基本公共服务体系的论述不够精当。而且,城乡(区域之间)基本公共服务的均等化并不能实现正义,在实际操作上也不可能达到均等(大体均等)这样的目标,甚至,反而会加剧不均等。因此,基本公共服务重视的不该是"均等",而是"多样化"。 展开更多
关键词 基本公共服务 均等化 城乡差异 三层理论
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金属包层长周期光纤光栅的理论和实验研究 被引量:5
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作者 张自嘉 施文康 +2 位作者 高侃 吉小军 方祖捷 《光学学报》 EI CAS CSCD 北大核心 2004年第7期897-901,共5页
金属包层长周期光纤光栅可用于对谐振波长的调谐。通过实验和理论研究了长周期光纤光栅在沉积金属包层前后谐振波长的变化规律。分析了金属包层光纤的特点 ,给出了金属包层光纤包层模的本征方程 ,并给出了这一复本征方程的求解方法。长... 金属包层长周期光纤光栅可用于对谐振波长的调谐。通过实验和理论研究了长周期光纤光栅在沉积金属包层前后谐振波长的变化规律。分析了金属包层光纤的特点 ,给出了金属包层光纤包层模的本征方程 ,并给出了这一复本征方程的求解方法。长周期光纤光栅在沉积金属包层后 ,对低阶包层模 ,谐振波长会向长波方向偏移 ,模次增加 ,偏移会增大 ;对高阶包层模 ,谐振波长向短波方向偏移。不同金属包层 ,谐振波长的偏移量也有一定差别。所给出的理论分析方法 ,可用于预测谐振波长的偏移方向和大小 。 展开更多
关键词 导波与光纤光学 长周期光纤光栅 金属包层光纤 三层介质光纤 包层模
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异构容器云间应用迁移模型研究 被引量:7
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作者 杨凯琪 赵玉龙 陈林 《计算机应用研究》 CSCD 北大核心 2020年第4期1097-1101,共5页
为解决基于Docker容器的应用跨异构容器云迁移的问题,针对主流的异构容器编排引擎的编排原理进行了研究,同时也研究了主流容器服务提供商之间的异构性,在此基础上提出了基于Docker容器的应用跨异构容器云迁移的三层模型。为提高基于Doc... 为解决基于Docker容器的应用跨异构容器云迁移的问题,针对主流的异构容器编排引擎的编排原理进行了研究,同时也研究了主流容器服务提供商之间的异构性,在此基础上提出了基于Docker容器的应用跨异构容器云迁移的三层模型。为提高基于Docker容器的应用跨异构容器云迁移的效率,提出基于镜像预同步的应用迁移技术。实验结果表明,利用三层模型能成功实现应用跨异构容器云的迁移,并且在引入镜像预同步技术前后,同构云异构容器编排引擎之间的应用迁移时间平均减少了60.33%,异构云Kubernetes集群间的应用迁移时间平均减少了43.67%。 展开更多
关键词 Docker容器 应用迁移 三层模型 异构容器云
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混合交通流交叉口共享空间交互行为建模及仿真 被引量:4
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作者 李逸昕 倪颖 孙剑 《交通运输系统工程与信息》 EI CSCD 北大核心 2022年第3期255-266,共12页
为准确刻画交叉口共享空间内交通个体的运动和交互过程,并为智能汽车虚拟测试提供可靠背景交通流仿真环境,本文提出一种混合交通流交叉口共享空间交互行为模型。基于人类认知过程,模型被设计为“感知-决策-执行”的3层通用框架结构,模... 为准确刻画交叉口共享空间内交通个体的运动和交互过程,并为智能汽车虚拟测试提供可靠背景交通流仿真环境,本文提出一种混合交通流交叉口共享空间交互行为模型。基于人类认知过程,模型被设计为“感知-决策-执行”的3层通用框架结构,模拟混合交通流中不同类型交通个体从感知、决策直至执行的交互全过程。感知层提出一种二维平面交互对象选择方法,通过个体感知范围和轨迹冲突有序筛选交互对象,表征冲突交互的动态性特征;决策层基于当前时刻的交互对象和实时交通环境状况,使用交互行为决策方法为不同类型的交通个体分别选择适合的行为进行交互;执行层通过计算生成执行当前行为决策所需要的轨迹、加速度等关键参数,共同控制仿真个体按照行为决策结果在二维平面上运动和交互。基于智能汽车Opendrive高精度路网,构建虚拟测试仿真平台,并将所提出的模型注入平台进行测试。仿真结果表明,模型能较好地复现交叉口共享空间中交通个体间的交互。研究结果有助于为智能汽车虚拟测试提供可靠背景交通流环境,并进一步提高虚拟测试工具的测试可信度、测试效率及泛化能力。 展开更多
关键词 交通工程 交互行为模型 三层通用框架 混合交通流交叉口 微观仿真 虚拟测试
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层流介质中金属板腐蚀电位分布研究 被引量:5
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作者 张建春 王向军 《国防科技大学学报》 EI CAS CSCD 北大核心 2018年第6期157-164,共8页
为了研究流动介质中产生的静电场,结合电化学和流体力学相关知识建立层流介质中金属板模型,利用贝塞尔函数展开及其逆运算推导出在三层介质中基于点电荷模型的腐蚀电位解析表达式,同时计算出金属板产生的电场。运用推导出的解析表达式... 为了研究流动介质中产生的静电场,结合电化学和流体力学相关知识建立层流介质中金属板模型,利用贝塞尔函数展开及其逆运算推导出在三层介质中基于点电荷模型的腐蚀电位解析表达式,同时计算出金属板产生的电场。运用推导出的解析表达式计算出在流动介质中任意场点处金属板随不同流速产生的腐蚀电位,并通过实验验证结果的正确性。结果表明,对层流条件下电化学反应产生的电流密度所建模型的结果与实验测量数据吻合度较高,同时电场分布也会随着流体流速及层流方向上长度的变化而发生变化。 展开更多
关键词 层流 三层介质 点电荷 电流密度 腐蚀电位 电场强度 金属板
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