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Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression 被引量:1
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作者 DONG Wen-bo ZHOU Li +2 位作者 DING Shi-feng WANG Ai-ming CAI Jin-yan 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期313-325,共13页
Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ... Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second. 展开更多
关键词 ice channel ship navigation IDENTIFICATION image segmentation corner point regression
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ELLIPTIC EQUATIONS IN DIVERGENCE FORM WITH DISCONTINUOUS COEFFICIENTS IN DOMAINS WITH CORNERS
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作者 Jun CHEN Xuemei DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1903-1915,共13页
We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across th... We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across the discontinuity surfaces and provide an example to illustrate the issue regarding the regularity at the corners. 展开更多
关键词 elliptic equations divergence form discontinuous coefficients corner regularity
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Topological laser on square lattice with gain–loss-induced higher-order corner modes
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作者 廖明杰 韦梅松 +2 位作者 王帅领 许静平 羊亚平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期189-195,共7页
We investigate the higher-order topological laser in the two-dimensional(2D) coupled-cavity array. By adding staggered on-site gain and loss to the 2D Hermitian array with a trivial phase, the system will emerge degen... We investigate the higher-order topological laser in the two-dimensional(2D) coupled-cavity array. By adding staggered on-site gain and loss to the 2D Hermitian array with a trivial phase, the system will emerge degenerate topological corner modes, which are protected by bulk band gap. For such a non-Hermitian model, by adjusting the parameters of the system and introducing the pumping into the cavity at the corner, a single-mode lasing with topological protection emerges.Furthermore, single-mode lasing exists over a wide range of pumping strengths. No matter where the cavity is initially stimulated, after enough time evolution, all the cavities belonging to the topological corner mode can emit a stable laser. 展开更多
关键词 topological corner modes nonlinear saturated gain single-mode lasing
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An angular blinking jamming method based on electronically controlled corner reflectors
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作者 GAN Lin WU Zehao +1 位作者 WANG Xuesong LI Jianbing 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期330-338,共9页
Passive jamming is believed to have very good potential in countermeasure community.In this paper,a passive angular blinking jamming method based on electronically controlled corner reflectors is proposed.The amplitud... Passive jamming is believed to have very good potential in countermeasure community.In this paper,a passive angular blinking jamming method based on electronically controlled corner reflectors is proposed.The amplitude of the incident wave can be modulated by switching the corner reflector between the penetration state and the reflection state,and the ensemble of multiple corner reflectors with towing rope can result in complex angle decoying effects.Dependency of the decoying effect on corner reflectors’radar cross section and positions are analyzed and simulated.Results show that the angle measured by a monopulse radar can be significantly interfered by this method while the automatic tracking is employed. 展开更多
关键词 monopulse radar angular blinking jamming corner reflector amplitude-comparison angle measurement metasurface
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Topological edge and corner states of valley photonic crystals with zipper-like boundary conditions
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作者 沈云峰 许孝芳 +2 位作者 孙铭 周文佶 常雅箐 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期480-491,共12页
We present a stable valley photonic crystal(VPC)unit cell with C_(3v)symmetric quasi-ring-shaped dielectric columns and realize its topological phase transition by breaking mirror symmetry.Based on this unit cell stru... We present a stable valley photonic crystal(VPC)unit cell with C_(3v)symmetric quasi-ring-shaped dielectric columns and realize its topological phase transition by breaking mirror symmetry.Based on this unit cell structure,topological edge states(TESs)and topological corner states(TCSs)are realized.We obtain a new type of wave transmission mode based on photonic crystal zipper-like boundaries and apply it to a beam splitter assembled from rectangular photonic crystals(PCs).The constructed beam splitter structure is compact and possesses frequency separation functions.In addition,we construct a box-shaped triangular PC structures with zipper-like boundaries and discover phenomena of TCSs in the corners,comparing its corner states with those formed by other boundaries.Based on this,we explore the regularities of the electric field patterns of TESs and TCSs,explain the connection between the characteristic frequencies and locality of TCSs,which helps better control photons and ensures low power consumption of the system. 展开更多
关键词 valley photonic crystal topological edge states topological corner states higher-order topological insulators topological phase transition
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Numerical Study of Co-flow Jet Control on Corner Separation in Compressor Cascade
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作者 Rui-ling Xu Tong-xi Li +1 位作者 Zhi-heng Wang Guang Xi 《风机技术》 2024年第5期25-33,共9页
The design objectives of modern aircraft engines include high load capacity,efficiency,and stability.With increasing loads,the phenomenon of corner separation in compressors intensifies,affecting engine performance an... The design objectives of modern aircraft engines include high load capacity,efficiency,and stability.With increasing loads,the phenomenon of corner separation in compressors intensifies,affecting engine performance and stability.Therefore,the adoption of appropriate flow control technology holds significant academic and engineering significance.This study employs the Reynolds-averaged Navier-Stokes(RANS)method to investigate the effects and mechanisms of active/passive Co-flow Jet(CFJ)control,implemented by introducing full-height and partial height jet slots between the suction surface and end wall of a compressor cascade.The results indicate that passive CFJ control significantly reduces the impact of corner separation at small incidence,with partial-height control further enhancing the effectiveness.The introduction of active CFJ enables separation control at large incidence,improving blade performance under different operating conditions.Active control achieves this by reducing the scale of corner separation vortices,effectively reducing the size of the separation region and enhancing blade performance. 展开更多
关键词 Compressor Cascade Co-flow Jet Control corner Separation Loss Analysis Vortex Structure Analysi
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互动 高效 创生——Unit 3 I like jiaozi best Lesson 9教学设计
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作者 王嘉慧 《中国信息技术教育》 2024年第4期15-17,共3页
创新整合点。本课借助信息技术教学有效地化抽象为具体,把难以理解的内容或者对理解知识起重要作用的内容,用多媒体展现出来,调动学生视觉功能,通过直观形象、生动的感官刺激,让学生最大限度地发挥潜能,在有限的时间里,全方位感知更多... 创新整合点。本课借助信息技术教学有效地化抽象为具体,把难以理解的内容或者对理解知识起重要作用的内容,用多媒体展现出来,调动学生视觉功能,通过直观形象、生动的感官刺激,让学生最大限度地发挥潜能,在有限的时间里,全方位感知更多的信息,提高教学效率,激活学习的内因。 展开更多
关键词 理解知识 视觉功能 化抽象为具体 感官刺激 信息技术教学 教学设计 lesson 发挥潜能
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LANGUAGE CORNER Lesson 15 This Tea Tastes Really Good 被引量:1
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《China Today》 1997年第3期66-67,共2页
关键词 LANGUAGE corner lesson 15 This Tea Tastes Really Good
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Language Corner:Lesson12
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《China Today》 1999年第12期66-67,共2页
关键词 华盛顿 Language corner:lesson12 小学三年级
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Language Corner:Lesson 14 “You’ve Become Really Addicted to Peking Opera”
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《China Today》 1997年第2期67-68,共2页
关键词 ve Become Really Addicted to Peking Opera You Language corner:lesson 14
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LANGUAGE CORNER:Lesson 10──My Son Is Filial
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《China Today》 1999年第10期64-65,共2页
关键词 LANGUAGE corner:lesson 10 My Son Is Filial
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Language corner:Lesson 18 The Farmers Are Better Off
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《China Today》 1997年第6期66-67,共2页
关键词 Zhang Language corner:lesson 18 The Farmers Are Better Off
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Language Corner:Lesson 21 Foreign Fast Food in Beijing
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《China Today》 1997年第9期66-67,共2页
关键词 LI Language corner:lesson 21 Foreign Fast Food in Beijing
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The cornerstone of fiber-optic distributed vibration/acoustic sensing: Ф-OTDR 被引量:1
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作者 Yunjiang Rao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第7期5-8,共4页
Fiber-optic distributed vibration/acoustic sensing(DVS/DAS) technology achieves breakthrough performance and explores broad cornerstone industrial applications.
关键词 cornerS BREAKTHROUGH fiber
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LANGUAGE CORNER:Lesson 4 Women Look Prettier in Qipao
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《China Today》 1999年第4期66-67,共2页
关键词 LANGUAGE corner:lesson 4 Women Look Prettier in Qipao
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Language Corner:Lesson 9--My Mother's Belief
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作者 SUN DEJIN 《China Today》 1999年第9期68-69,共2页
关键词 信仰自由 Language corner:lesson 9 My Mother’s Belief
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Language Corner lesson 12:Changing Money
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作者 the National Office for Teaching Chinese as a Foreign Language (NOTCFL) 《China Today》 2005年第12期80-81,共2页
关键词 Office Language corner lesson 12:Changing Money
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Language Corner: Lesson 19We Cooperated Well Last Time
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《China Today》 1997年第7期68-69,共2页
关键词 We Language corner lesson 19We Cooperated Well Last Time
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LANGUAGE CORNER Lesson 16 "Was I Wrong?
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《China Today》 1997年第4期66-67,共2页
关键词 LANGUAGE corner lesson 16 Was I Wrong
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LANGUAGE CORNER: Lesson 11 Northerners Like Jasmine Tea
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《China Today》 1999年第11期64-65,共2页
关键词 LANGUAGE corner lesson 11 Northerners Like Jasmine Tea
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