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Semantic segmentation via pixel-to-center similarity calculation

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 87-100页

作者： Dongyue Wu Zilin Guo Aoyan Li Changqian Yu Nong Sang Changxin Gao National Key Laboratory of Science and Technology on Multispectral Information Processing School of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhanChina Meituan inc. BeijingChina

Sinc. the fully convolutional network has achieved great success in semantic segmentation,lots of works have been proposed to extract discriminative pixel ***,the authors observe that existing methods still suffer from two typical challenges:(i)The intra-class feature variation between different scenes may be large,leading to the difficulty in maintaining the consistency between same-class pixels from different scenes;(ii)The inter-class feature distinc.ion in the same scene could be small,resulting in the limited performance to distinguish different classes in each *** authors first rethink se-mantic segmentation from a perspective of similarity between pixels and class *** weight vector of the segmentation head represents its corresponding semantic class in the whole dataset,which can be regarded as the embedding of the class ***,the pixel-wise classification amounts to computing similarity in the final feature space between pixels and the class *** this novel view,the authors propose a Class Center Similarity(CCS)layer to address the above-mentioned challenges by generating adaptive class centers conditioned on each scenes and supervising the similarities between class *** CCS layer utilises the Adaptive Class Center Module to generate class centers conditioned on each scene,which adapt the large intra-class variation between different *** designed Class Distance Loss(CD Loss)is introduced to control both inter-class and intra-class distances based on the predicted center-to-center and pixel-to-center ***,the CCS layer outputs the processed pixel-to-center similarity as the segmentation *** experiments demonstrate that our model performs favourably against the state-of-the-art methods.

关键词： computer vision deep neural networks image segmentation scene understanding

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SiP的模块化发展趋势

电子与封装 2024年第7期24卷 21-28页

作者： William Koh Pacrim Technology inc. IrvineCA 92602

系统级封装(SiP)技术已广泛应用于移动设备、可穿戴设备、健康和医疗设备、人工智能(AI)、物联网(IoT)和汽车电子。SiP采用异构集成的方式,将各种芯片和元件集成到一个封装中,以实现特定功能,并具有节省电路板空间、简化布局设计和降低... 详细信息

系统级封装(SiP)技术已广泛应用于移动设备、可穿戴设备、健康和医疗设备、人工智能(AI)、物联网(IoT)和汽车电子。SiP采用异构集成的方式,将各种芯片和元件集成到一个封装中,以实现特定功能,并具有节省电路板空间、简化布局设计和降低制造成本等优势。随着电子组件的小型化发展方向不断持续,一些SiP已经发展成为模块或系统级模块(SiM),可以直接连接并安装到器件中。回顾了SiP从多芯片模块(MCM)、多芯片封装(MCP)到高级芯粒封装和共封装光学器件(CPO)的演变。未来几年,更多的SiP将变成SiM,直接连接器件或系统。

关键词：系统级封装系统级模块多芯片模块

Multiple Matching Attenuation Based on Curvelet Domain Extended Filtering

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Journal of Ocean University of China 2024年第4期23卷 924-932页

作者： HUA Qingfeng CHEN Zhang HE Huili TAN Jun CHEN Haifeng LI Guanbao SONG Peng ZHAO Bo JIANG Xiuping Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China College of Marine Geoscience Ocean University of ChinaQingdao 266100China BGP inc. China National Petroleum CorporationZhuozhou 072750China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationQingdao 266100China

The paper develops a multiple matching attenuation method based on extended filtering in the curvelet domain,which combines the traditional Wiener filtering method with the matching attenuation method in curvelet ***,the method uses the predicted multiple data to generate the Hilbert transform records,time derivative records and time derivative records of Hilbert ***,the above records are transformed into the curvelet domain and multiple matching attenuation based on least squares extended filtering is ***,the attenuation results are transformed back into the time-space *** on the model data and field data show that the method proposed in the paper effectively suppress the multiples while preserving the primaries ***,it has higher accuracy in eliminating multiple reflections,which is more suitable for the multiple attenuation tasks in the areas with complex structures compared to the time-space domain extended filtering method and the conventional curvelet transform method.

关键词： multiple matching attenuation curvelet domain extended filtering

Design and guidance of a multi-active debris removal mission

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Astrodynamics 2023年第4期7卷 383-399页

作者： Minduli C.Wijayatunga(B) Roberto Armellin Harry Holt Laura Pirovano Aleksander A.Lidtke Te Pūnaha Atea–space Institute The University of AucklandAuckland 1010New Zealand Astroscale Japan inc. 1-16-4-16 KinshiSumida-kuTokyoJapan

space debris have become exceedingly dangerous over the years as the number of objects in orbit continues to *** debris removal(ADR)missions have gained significant interest as effective means of mitigating the risk of collision between objects in *** study focuses on developing a multi-ADR mission that utilizes controlled reentry and *** mission comprises two spacecraft:a Servicer that brings debris to a low altitude and a Shepherd that rendezvous with the debris to later perform a controlled reentry.A preliminary mission design tool(PMDT)was developed to obtain time and fuel optimal trajectories for the proposed mission while considering the effect of J2,drag,eclipses,and duty *** PMDT can perform such trajectory optimizations for multi-debris missions with computational time under a *** guidance schemes are also studied,taking the PMDT solution as a reference to validate the design methodology and provide guidance solutions to this complex mission profile.

关键词： active debris removal(ADR) trajectory design optimization autonomous guidance low-thrust electric propulsion △u-law guidance Q-law guidance

Low Thrust Minimum Time Orbit Transfer Nonlinear Optimization Using Impulse Discretization via the Modified Picard–Chebyshev Method

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Computer Modeling in Engineering & Sciences 2016年第1期111卷 1-27页

作者： Darin Koblick Shujing Xu Joshua Fogel Praveen Shankar California State University-Long Beach CAUSA. millennium space systems inc. El SegundoCAUSA. Claremont Graduate University CAUSA. University of California-San Diego CAUSA. University of Southern California Los AngelesCAUSA.

The Modified Picard-Chebyshev Method(MPCM)is implemented as an orbit propagation solver for a numerical optimization method that determines minimum time orbit transfer trajectory of a satellite using a series of multiple impulses at intermediate *** waypoints correspond to instantaneous impulses that are determined using a nonlinear constrained optimization routine,SNOPT with numerical force models for both Two-Body and J2 *** is found that using the MPCM inc.eases run-time performance of the discretized lowthrust optimization method when compared to other sequential numerical solvers,such as Adams-Bashforth-Moulton and Gauss-Jackson 8th order methods.

关键词： Low Thrust Picard–Chebyshev Optimization Multi-Impulse Boundary Value Problem.

Event-based optimization with random packet dropping

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Science China(Information Sciences) 2020年第11期63卷 175-194页

作者： Qing-Shan JIA Jing-Xian TANG Zhenning LANG Center for Intelligent and Networked systems Department of AutomationTsinghua University NetEase inc.

Event-based optimization(EBO) provides a general framework for policy optimization in many discrete event dynamic systems where decision making is triggered by events that represent state transitions with common features. Because the number of events can be defined by the user and usually inc.eases linearly with respect to the system scale, EBO has good potential to address large-scale problems where the state space grows exponentially. However, in many practical systems, sensors are geographically distributed and connected to a central controller through imperfect communication channels. Therefore, events observed by the sensors may not reach the controller. Optimization methods of event-based policies in these cases have not yet been identified. In this paper, we consider this important problem and make three major contributions. First, we formulate a mathematical EBO model in which the communication between sensors and controllers is subject to random packet dropping. Second, we show that this EBO model can be converted to another EBO model with perfect communication. Then, the performance difference equation and the performance derivative equation for event-based policies are straightforward to develop. One gradient-based policy iteration algorithm is developed for problems where the state transition probabilities are explicitly known, while another for problems where they are unknown. Third, the performance of the algorithms and the impact of the packet dropping probability on policy performance are numerically demonstrated on a single-zone occupant level estimation problem in buildings.

关键词： event-based optimization packet dropping discrete event dynamic systems

The Ontology of Velocity

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Journal of Modern Physics 2023年第6期14卷 1003-1017页

作者： Edwin Eugene Klingman Cybernetic Micro systems Inc. San Gregorio USA

Special relativity formulates a world partitioned into frames in relative motion;absolute motion is prohibited by axiom: no preferred frame, with consequences for the ontology of velocity. The best guide to physical reality is experiment, so ontology of velocity is investigated in the context of primordial field theory in terms of three experiments: Michelson-Morley, Michelson-Gale and Hafele-Keating experiments.

关键词： spacetime Ontology Comparative Ontology Local Absolute space Relativistic Mass C-Field Circulation Primordial Field Theory Michelson-Morley Michelson-Gale Hafele-Keating

Inverse Differential Operators in Time and space

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Journal of Applied Mathematics and Physics 2023年第12期11卷 3789-3799页

作者： Edwin Eugene Klingman Cybernetic Micro systems Inc. San Gregorio USA

When one function is defined as a differential operation on another function, it’s often desirable to invert the definition, to effectively “undo” the differentiation. A Green’s function approach is often used to accomplish this, but variations on this theme exist, and we examine a few such variations. The mathematical analysis of is sought in the form if such an inverse operator exists, but physics is defined by both mathematical formula and ontological formalism, as I show for an example based on the Dirac equation. Finally, I contrast these “standard” approaches with a novel exact inverse operator for field equations.

关键词： Matrix-Inverse Differential Operators Green’s Functions Dirac’s Equation Wave Equations Inverse Curl Operator

A Re-Interpretation of Quasi-Local Mass

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Journal of Modern Physics 2022年第4期13卷 347-367页

作者： Edwin Eugene Klingman Cybernetic Micro systems Inc. San Gregorio CA USA

Because the equivalence princ.ple forbids local mass density, we cannot formulate general relativistic mass as an integral over mass density as in Newtonian gravity. This century-old problem was addressed forty years ago by Penrose, and many papers have sinc. extended the concept. Currently there is no satisfactory physical understanding of the nature of quasi-local mass. In this paper I review the key issues, the current status, and propose an alternative interpretation of the problem of local mass and energy density for gravity systems from an information perspective.

关键词： Quasi-Local Mass Curved space-Time Gravitational Energy Stress-Energy Tensor Encoding Information in Geometry Schwarzschild Metric