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Energy Efficiency Optimization for Full-Duplex D2D Communications Underlaying Distributed Antenna Systems

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IEEE Transactions on Green Communications and Networking

IEEE Transactions on Green Communications and Networking 2024年

作者： Liu, Zhan Liao, Zhiyuan Li, Chunquan Zhang, Zhijun Yu, Junzhi Liu, P.X. Hunan University of Humanities Science and Technology School of Information Loudi417000 China Nanchang University School of Information Engineering Nanchang330031 China Jiangxi Provincial Key Laboratory of Intelligent Systems and Human-Machine Interaction Nanchang330031 China South China University of Technology School of Automation Science and Engineering Guangzhou510640 China Peking University State Key Laboratory for Turbulence and Complex Systems Department of Advanced Manufacturing and Robotics College of Engineering Beijing100871 China Carleton University Department of Systems and Computer Engineering OttawaONK1S 5B6 Canada

In this paper, we investigate the total system energy efficiency (EE) of full-duplex (FD) device-to-device (D2D) communications underlaying distributed antenna systems (DAS), where remote access units (RAUs), D2D users (DUs), and cellular users (CUs) are all capable of FD operation. Specifically, we jointly optimize subcarrier assignment and power allocation under the quality of service (QoS) requirements of CUs and DUs and the maximum power constraints of RAUs, CUs, and DUs. In addition, we propose a novel spectrum sharing strategy that allows each subcarrier to be assigned to multiple CUs and/or multiple D2D pairs (DPs) for flexibility. To solve the formulated non-convex optimization problem, we first employ fractional programming to transform the objective function in the optimization problem from the fractional form into the equivalent subtractive form. Then, an efficient iterative resource allocation algorithm is proposed, which needs to solve an inner problem in each iteration. After relaxing the variables and introducing penalty factors, the non-convex inner problem is transformed into a convex problem through the successive convex approximation (SCA) method and solved by iterative algorithm. Simulation results demonstrate that the proposed algorithm can considerably improve the system EE compared to other benchmark schemes. Furthermore, the proposed spectrum sharing strategy is superior to the existing sharing strategies. © 2017 IEEE.

关键词： Convex optimization

Near-field thermal transport between two identical twisted bilayer graphene sheets separated by a vacuum gap

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Physical Review B 2021年第23期103卷 235415-235415页

作者： Fuwei Yang Bai Song Beijing Innovation Center for Engineering Science and Advanced Technology Peking University Beijing 100871 China Center for Nano and Micro Mechanics Tsinghua University Beijing 100084 China Department of Energy and Resources Engineering Peking University Beijing 100871 China Department of Advanced Manufacturing and Robotics Peking University Beijing 100871 China

Active control of heat flow is of both fundamental and applied interest in thermal management and energy conversion. Here, we present a fluctuational electrodynamic study of thermal radiation between twisted bilayer graphene (TBLG), motivated by its unusual and highly tunable plasmonic properties. We show that near-field heat flow can vary by more than 10-fold over only a few degrees of twist, and observe a larger variation with increasing chemical potential and decreasing temperature. Further, we identify special angles leading to heat flow extrema, which are dictated by the Drude weight in the intraband optical conductivity of TBLG, and are roughly linear with the chemical potential. As the twist angle decreases, we observe multiband thermal transport due to the increasing role of interband transitions, in analogy to monolayer graphene in a magnetic field. We also briefly discuss the effect of a small angular deviation and a substrate, which are experimentally relevant. Our findings are understood via the surface plasmons in TBLG, and highlight its potential for manipulating radiative heat flow.

关键词： Heat transfer Optical conductivity Surface plasmon polariton Transport phenomena Graphene Electromagnetic wave theory Landauer formula Linear response theory

Cubic boron arsenide: An emerging semiconductor with exceptional thermal conductivity and high carrier mobility

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Matter 2025年第5期8卷

作者： Yue, Shuai Tian, Fei Song, Bai Zhong, Yangguang Bao, Jiming Liu, Xinfeng CAS Key Laboratory of Standardization and Measurement for Nanotechnology National Center for Nanoscience and Technology Beijing100190 China School of Materials Science and Engineering Sun Yat-sen University Guangdong Guangzhou510006 China Department of Energy and Resources Engineering and Department of Advanced Manufacturing and Robotics Peking University Beijing100871 China Department of Electrical and Computer Engineering and Texas Center for Superconductivity University of Houston HoustonTX77204 United States University of Chinese Academy of Sciences Beijing100049 China College of Materials Science and Engineering Hunan University Hunan Changsha410082 China

Over the past decade, cubic boron arsenide (BAs) has emerged as a highly promising semiconductor owing to its extraordinary thermal conductivity (1,200 W/m·K) and high ambipolar mobility (1,600 cm2/V·s). This unique combination has spurred significant research interest in its potential for advanced device applications. However, the challenge of growing uniform, high-quality crystals has hindered its widespread adoption, limiting its realization in high-performance devices. To accelerate the development and utilization of BAs, we systematically review recent theoretical and experimental advancements, focusing on key aspects such as carrier mobility, carrier relaxation, and the impact of defects on thermal conductivity and carrier mobility. Additionally, we explore emerging applications, persistent challenges, and future research directions. By addressing these critical issues, we aim to inspire further research and facilitate the development of next-generation electronic and optoelectronic devices based on BAs. © 2025 Elsevier Inc.

关键词： Carrier mobility

Diff9D: Diffusion-Based Domain-Generalized Category-Level 9-DoF Object Pose Estimation

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arXiv 2025年

作者： Liu, Jian Sun, Wei Yang, Hui Deng, Pengchao Liu, Chongpei Sebe, Nicu Rahmani, Hossein Mian, Ajmal National Engineering Research Center for Robot Visual Perception and Control Technology College of Electrical and Information Engineering School of Robotics State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha410082 China Institute of Artificial Intelligence and Robotics Xi’an Jiaotong University Xi’an710049 China Department of Information Engineering and Computer Science University of Trento Trento38123 Italy School of Computing and Communications Lancaster University LA1 4YW United Kingdom Department of Computer Science The University of Western Australia WA6009 Australia

Nine-degrees-of-freedom (9-DoF) object pose and size estimation is crucial for enabling augmented reality and robotic manipulation. Category-level methods have received extensive research attention due to their potential for generalization to intra-class unknown objects. However, these methods require manual collection and labeling of large-scale real-world training data. To address this problem, we introduce a diffusion-based paradigm for domain-generalized category-level 9-DoF object pose estimation. Our motivation is to leverage the latent generalization ability of the diffusion model to address the domain generalization challenge in object pose estimation. This entails training the model exclusively on rendered synthetic data to achieve generalization to real-world scenes. We propose an effective diffusion model to redefine 9-DoF object pose estimation from a generative perspective. Our model does not require any 3D shape priors during training or inference. By employing the Denoising Diffusion Implicit Model, we demonstrate that the reverse diffusion process can be executed in as few as 3 steps, achieving near real-time performance. Finally, we design a robotic grasping system comprising both hardware and software components. Through comprehensive experiments on two benchmark datasets and the real-world robotic system, we show that our method achieves state-of-the-art domain generalization performance. Our code will be made public at https://***/CNJianLiu/Diff9D. Copyright © 2025, The Authors. All rights reserved.

关键词： Augmented reality

Multiple Functions Printed Circuit Triboelectric Nanogenerators-Based Metauniverse Sport Interactive System

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SSRN

SSRN 2023年

作者： Zhu, Yongsheng Zhao, Tianming Sun, Fengxin Jia, Changjun Ye, Hui Jiang, Yawei Wang, Kuo Huang, Chaorui Xie, Yannan Mao, Yupeng Physical Education Department Northeastern University Shenyang110819 China State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Science Shenyang China Key Laboratory for Organic Electronics and Information Displays Institute of Advanced Materials Jiangsu Key Laboratory for Biosensors Jiangsu National Synergetic Innovation Center for Advanced Materials Nanjing University of Posts and Telecommunications Jiangsu Nanjing China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of Sciences Shenyang China College of Information Science and Engineering Northeastern University Shenyang China School of Strength and Conditioning Training Beijing Sport University Beijing China

Metauniverse is a future society based on the convergence of the physical and the digital world, which is fully indebted to the sophisticated human-machine interface (HMI) to connect the two worlds. In this study, a metauniverse sport interactive system based on TENG has been developed, realizing interaction with human beings, devices, and the internet in real-time. This metauniverse sport interactive system is consistent with a self-powered anaerobic power meter (APM), a wireless transmission module, personalized data analysis based on the professional Wingate anaerobic power test method, and an augmented reality (AR) application. Self-powered APM is integrated with the axles of the bicycle to monitor human exercises, such as peak power (PP), mean power (MP), and fatigue index (FI). The data is transmitted to the cloud by the wireless transmission module and users can freely explore the metauniverse through the AR application. As a result of machine learning, the professional Wingate anaerobic power test method can not only reflect the anaerobic capacity, but also be used for athlete selection. This work provides a new approach to online competitions, sport training, and athlete selection and provides a new way to build metauniverse. © 2023, The Authors. All rights reserved.

关键词： Human computer interaction

An Illumination-Robust Feature Extractor Augmented by Relightable 3D Reconstruction

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arXiv 2024年

作者： Zhao, Shunyi Yu, Zehuan Fan, Zuxin Zhou, Zhihao Ruan, Lecheng Wang, Qining College of Engineering Peking University Beijing100871 China Department of Electronic and Computer Engineering Hong Kong University of Science and Technology Hong Kong Institute for Artificial Intelligence Peking University Beijing100871 China Beijing Engineering Research Center of Intelligent Rehabilitation Engineering Beijing100871 China Department of Advanced Manufacturing and Robotics College of Engineering Peking University Beijing100871 China University of Health and Rehabilitation Sciences Qingdao China

Visual features, whose description often relies on the local intensity and gradient direction, have found wide applications in robot navigation and localization in recent years. However, the extraction of visual features is usually disturbed by the variation of illumination conditions, making it challenging for real-world applications. Previous works have addressed this issue by establishing datasets with variations in illumination conditions, but can be costly and time-consuming. This paper proposes a design procedure for an illuminationrobust feature extractor, where the recently developed relightable 3D reconstruction techniques are adopted for rapid and direct data generation with varying illumination conditions. A self-supervised framework is proposed for extracting features with advantages in repeatability for key points and similarity for descriptors across good and bad illumination conditions. Experiments are conducted to demonstrate the effectiveness of the proposed method for robust feature extraction. Ablation studies also indicate the effectiveness of the self-supervised framework design. © 2024, CC BY.

关键词： Feature extraction

Study on Mechanical Properties of Dual-Channel Cryogenic 3d Printing Scaffold for Mandibular Defect Repair

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SSRN

SSRN 2023年

作者： Gao, Lilan Sun, Mengchao Liu, Jie Meng, Lulu Liu, Han Zheng, Xiongfei Liu, Hao Li, Ruixin Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300382 China Tianjin300382 China Beijing Friendship Hospital Capital Medical University 100050 China State Key Laboratory of Robotics Institutes for Robotics and Intelligent Manufacturing Shenyang Institute of Automation Chinese Academy of Sciences Shenyang110017 China Tianjin Key Laboratory of Oral and Maxillofacial Function Reconstruction Tianjin Stomatological Hospital The Affiliated Stomatological Hospital of Nankai University Tianjin300041 China

Mandibular defect repair has always been a clinical challenge, facing technical bottleneck. The new materials directly affect technological breakthroughs in mandibular defect repair field. Our aim is to fabricate a scaffold for mandibular defect repairing with advanced biomaterials. Therefore, a novel dual-channel printed scaffold consisting of silk fibroin/collagen type I /hydroxyapatite (SCH) and polycaprolactone/hydroxyapatite (PCL/HA) was fabricated by 3D printing technology with double nozzles. The mechanical properties and behaviors of dual-channel printed scaffold were investigated by performing uniaxial compression, creep, stress relaxation and ratcheting experiments respectively. The experiments indicated the Young modulus of dual-channel printed scaffold was 60.1 kPa and dual-channel printed scaffold was typical nolinear viscoelastic consistent with bone tissue. Finite Element Analysis (FEA) was employed performing a numerical simulation to evaluate the implantation effect in mandible. The stress distribution of the contact area between scaffold and defect was uniform, the maximum Mises stress of cortical bone and cancellous bone in defect area were 54.52MPa and 3.196MPa, and the maximum displacement of cortical bone and cancellous bone in defect area were 0.1575mm and 0.1555mm, which were distributed in the incisor region. The peak value of the maximum Mises stress for the scaffold implanted was 3.128× MPa and the maximum displacement was 6.453×mm distributed near incisor area. The displacement distribution of the scaffold was consistent with that of cortical and cancellous bone. The scaffold recovered well when the force applied on it disappeared. Above all, dual-channel printed scaffold had excellent bio-mechanical properties in implanting mandible, which provides a new idea for the reconstruction of irregular bone defects in the mandible and has good clinical development prospects. © 2023, The Authors. All rights reserved.

关键词： 3D printing

NeRF in robotics: A Survey

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arXiv 2024年

作者： Wang, Guangming Pan, Lei Peng, Songyou Liu, Shaohui Xu, Chenfeng Miao, Yanzi Zhan, Wei Tomizuka, Masayoshi Pollefeys, Marc Wang, Hesheng The University of Cambridge ETH Zurich Switzerland The Department of Automation Shanghai Jiao Tong University Shanghai200240 China The Key Laboratory of System Control and Information Processing Ministry of Education of China China Engineering Research Center of Intelligent Control for Underground Space Ministry of Education School of Information and Control Engineering Advanced Robotics Research Center China University of Mining and Technology Xuzhou221116 China ETH Zurich Zurich Switzerland Mechanical Systems Control Laboratory University of California Berkeley United States

Meticulous 3D environment representations have been a longstanding goal in computer vision and robotics fields. The recent emergence of neural implicit representations has introduced radical innovation to this field as implicit representations enable numerous capabilities. Among these, the Neural Radiance Field (NeRF) has sparked a trend because of the huge representational advantages, such as simplified mathematical models, compact environment storage, and continuous scene representations. Apart from computer vision, NeRF has also shown tremendous potential in the field of robotics. Thus, we create this survey to provide a comprehensive understanding of NeRF in the field of robotics. By exploring the advantages and limitations of NeRF, as well as its current applications and future potential, we hope to shed light on this promising area of research. Our survey is divided into two main sections: The Application of NeRF in robotics and The Advance of NeRF in robotics, from the perspective of how NeRF enters the field of robotics. In the first section, we introduce and analyze some works that have been or could be used in the field of robotics from the perception and interaction perspectives. In the second section, we show some works related to improving NeRF's own properties, which are essential for deploying NeRF in the field of robotics. In the discussion section of the review, we summarize the existing challenges and provide some valuable future research directions for reference. © 2024, CC BY-NC-ND.

关键词： robotics

SC-NeRF: Self-Correcting Neural Radiance Field with Sparse Views

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arXiv 2023年

作者： Song, Liang Wang, Guangming Liu, Jiuming Fu, Zhenyang Miao, Yanzi Wang, Hesheng Engineering Research Center of Intelligent Control for Underground Space Ministry of Education School of Information and Control Engineering Advanced Robotics Research Center China University of Mining and Technology Xuzhou221116 China Department of Automation Key Laboratory of System Control and Information Processing of Ministry of Education Key Laboratory of Marine Intelligent Equipment and System of Ministry of Education Shanghai Engineering Research Center of Intelligent Control and Management Shanghai Jiao Tong University Shanghai200240 China

In recent studies, the generalization of neural radiance fields for novel view synthesis task has been widely explored. However, existing methods are limited to objects and indoor scenes. In this work, we extend the generalization task to outdoor scenes, trained only on object-level datasets. This approach presents two challenges. Firstly, the significant distributional shift between training and testing scenes leads to black artifacts in rendering results. Secondly, viewpoint changes in outdoor scenes cause ghosting or missing regions in rendered images. To address these challenges, we propose a geometric correction module and an appearance correction module based on multi-head attention mechanisms. We normalize rendered depth and combine it with light direction as query in the attention mechanism. Our network effectively corrects varying scene structures and geometric features in outdoor scenes, generalizing well from object-level to unseen outdoor scenes. Additionally, we use appearance correction module to correct appearance features, preventing rendering artifacts like blank borders and ghosting due to viewpoint changes. By combining these modules, our approach successfully tackles the challenges of outdoor scene generalization, producing high-quality rendering results. When evaluated on four datasets (Blender, DTU, LLFF, Spaces), our network outperforms previous methods. Notably, compared to MVSNeRF, our network improves average PSNR from 19.369 to 25.989, SSIM from 0.838 to 0.889, and reduces LPIPS from 0.265 to 0.224 on Spaces outdoor scenes. © 2023, CC BY.

关键词： Rendering (computer graphics)