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4th IEEE International Conference on Image, Vision and Computing, ICIVC 2019

作者： Liu, Xipeng Chen, Jianxin Kang, Bin Zhang, Xuguang Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing China

ISBN: (纸本)9781728123257

Although deep learning has dominated the ship detection domain, it still has two challenges: arbitrary-oriented densely arranged ships cause detection omissions and large scale image contains redundant areas. This paper proposes an effective convolutional neural network framework for arbitrary-oriented ship detection in large scale and complex scenes. In this framework, we propose Cumulative Feature Pyramid networks for multi-receptive-field feature fusion, which enhances high-level semantic information at all scales. Based on the outputs of Region Proposal networks, Rotation Region Locating network predicts rotation bounding box of arbitrary-oriented ships and adopts rotation intersection over union to avoid the effect of ship dense arrangement. For large scale scenes, No-Ship Area Suppression uses OTSU algorithm to generate binary mask and then filter out non-ship regions to reduce redundant computations. Additionally, we firstly build a remote sensing image dataset for ship detection, which contains 4237 images and over 21200 ships. Experimental comparisons with the state-of-the-art approaches validate the effectiveness, accuracy and robustness of the proposed method. © 2019 IEEE.

关键词： Ships

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A Gridless Wideband DOA Estimation Based On Atomic Norm Minimization

A Gridless Wideband DOA Estimation Based On Atomic Norm Mini...

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sensor Array and Multichannel Signal Processing Workshop

作者： Yuanyuan Jiang Dan Li Xiaohuan Wu Wei-Ping Zhu Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (数字)9781728119465

ISBN: (纸本)9781728119472

This paper proposes a new method for wideband directionof-arrival (DOA) estimation. The main idea of the proposed method is focusing the array output on frequency point to the reference frequency point. But different from coherent signalsubspace method (CSSM), it has no requirement of an initial DOA estimation. Atomic norm minimization (ANM) is then applied after the focusing step. Our proposed method is able to achieve better estimation performance than other wideband DOA estimators. Numerical simulations are carried out to demonstrate the performance of the proposed method compared to existing ones.

关键词： Direction-of-arrival estimation Frequency-domain analysis Simulation Conferences Estimation Focusing Minimization

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Study on the segmentation method of multi-phase CT liver tumor based on dual channel U-Nets

Study on the segmentation method of multi-phase CT liver tum...

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2020 International Symposium on Automation, Information and Computing, ISAIC 2020

作者： Xu, Changchang Hu, Dong Zhang, YaoDong Pang, Yuwei Jiangsu Province’s Key Lab of Image Procession and Image Communications Nanjing University of Posts and Telecommunications Nanjing210003 China Education Ministry’s Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210003 China Education Ministry’s Engineering Research Center of Ubiquitous Network and Heath Service Nanjing University of Posts and Telecommunications Nanjing210003 China first clinical medical college of Nanjing Medical University Nanjing University of Posts and Telecommunications Nanjing210003 China

As a common malignant tumor disease, hepatocellular carcinoma is the most common cancers in the world. The incidence of hepatocellular carcinoma in China is higher than that in the world. Therefore, it is very important for doctors to separate liver and tumor from CT images by means of computer-aided diagnosis and treatment. In this paper, a multiscale DC-CUNets network liver tumor segmentation method is proposed to enhance the fusion of multi-phase image features in CT, the scale of liver tumors, and the optimization of network training process. (1) A multistage CT liver tumor segmentation method based on two-channel cascaded U-Nets (DC-CUNets) is proposed. The liver was segmented using the first-order U-Net, and then the segmented area of interest of the liver was input into the second-order U-Net network to segment liver tumors. We designed two-channel U-Nets to learn the image characteristics of CT images in arterial and venous phases respectively, and to achieve two-channel feature fusion through feature cascade to improve the overall accuracy of liver tumor segmentation.(2) A multistage CT liver tumor segmentation method based on multiscale DC-CUNets was proposed. For the scale problem of liver tumors, we designed a two-layer multiscale void convolution module to obtain image features at different scales for large, medium and small tumors, and fuse the multiscale features at the output of the module. We have replaced the convolution layer of the fourth module in the second-order two-channel liver tumor segmentation U-Nets by the two-layer multiscale cavity convolution module to implement multiscale DC-CUNets. © 2021 Institute of Physics Publishing. All rights reserved.

关键词： Convolution

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A Gridless Method for Doa Estimation Under the Coexistence of Mutual Coupling and Unknown Nonuniform Noise

A Gridless Method for Doa Estimation Under the Coexistence o...

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sensor Array and Multichannel Signal Processing Workshop

作者： Dan Li Yuanyuan Jiang Xiaohuan Wu Wei-Ping Zhu Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (数字)9781728119465

ISBN: (纸本)9781728119472

This paper addresses the issue of direction-of-arrival (DOA) estimation under the coexistence of mutual coupling and nonuniform noise. We first construct a selection matrix based on the structural characteristics of the mutual coupling matrix (MCM) to form a new manifold matrix which is not affected by the mutual coupling effect. Then, we employ the covariance fitting criteria to form a semidefinite programming for DOA estimation. Compared to most of existing sparse methods, our method does not require discretization of the angle space, hence is able to achieve super-resolution. Simulations are carried out to verify the effectiveness of the propose method.

关键词： Manifolds Mutual coupling Direction-of-arrival estimation Fitting Superresolution Estimation Signal processing algorithms

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Reference-frame-independent measurement-device-independent quantum key distribution using fewer states

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Physical Review A 2021年第2期103卷 022602-022602页

作者： Jing-Yang Liu Xing-Yu Zhou Qin Wang Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Broadband Wireless Communication and Sensor Network Technology Key Laboratory of Ministry of Education Ministry of Education Nanjing 210003 China Telecommunication and Networks National Engineering Research Center NUPT Nanjing 210003 China

Reference-frame-independent measurement-device-independent quantum key distribution (RFI-MDI-QKD) is immune to both detector side channel attacks and slow drifts of reference frames, and thus possesses a high level of security. In the traditional protocol of RFI-MDI-QKD, each legitimate user, Alice or Bob, has to prepare six encoding states in three orthogonal bases (X, Y, and Z), which are sent to the untrusted third party, Charlie. Then all the successful counting events are utilized for parameter estimations, which suffer from a severe finite-size effect. In this paper, we propose a scheme on RFI-MDI-QKD with fewer states and demonstrate that it can be secured and made useful by utilizing semidefinite programming. Numerical simulation results reveal the equivalence between those groups of different monitoring states from Alice and Bob. In addition, when considering practical experimental conditions and taking finite-size effects into account, our proposal can achieve a better performance than the traditional six-state RFI-MDI scheme, which provides a resource-saving and simpler state-preparation approach for practical implementations without sacrificing key rates.

关键词： Quantum communication Quantum cryptography

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Spectral Efficiency Analysis of Downlink Transmission for Two-Way Cell-Free Massive MIMO System With Few-Bit ADCs

Spectral Efficiency Analysis of Downlink Transmission for Tw...

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IEEE International Symposium on Personal, Indoor and Mobile Radio communications (PIMRC)

作者： Jiaxi Cui Pei Liu Kehao Wang Hongkuan Zhou Yue Zhang Xinghua Sun Stefano Buzzi School of Information Engineering Wuhan University of Technology Wuhan China Ministry of Education Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Nanjing China Science and Technology on Thermal Energy and Power Laboratory Wuhan 2nd Ship Design and Research Institute Wuhan China Department of Electronic and Information Engineering Shantou University Shantou China School of Electronics and Communication Engineering Sun Yat-sen University Guangdong China University of Cassino and Southern Lazio Cassino Italy Politecnico di Milano Milano Italy

This paper studies the downlink spectral efficiency of a two-way cell-free massive multiple-input multiple-output system with few-bit analog-to-digital converts (ADCs). By utilizing minimum mean squared error channel estimation method and maximal-ratio transmission precoder, we derive a closed-form expression for the effective downlink signal-to-interference-plus-noise ratio (SINR), which applies to any number of access point (AP) antennas M and distortion factors of ADCs in both AP and user pair sides. Additionally, the obtained analytical expression specializes to the conventional one when the ideal ADCs are adopted. Moreover, the asymptotic performance and power scaling law of the effective SINR in high M regime are studied. The corresponding analysis indicates that increasing M can provide considerable gains to compensate the rate loss caused by non-ideal ADCs and also, appropriately cutting down the pilot power and transmission power will not affect the SINR performance in high M region. Finally, all the theoretical results are verified via simulations.

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Multigrating design for integrated single-atom trapping, manipulation, and readout

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Physical Review A 2022年第5期105卷 053520-053520页

作者： Aiping Liu Jiawei Liu Wei Peng Xin-Biao Xu Guang-Jie Chen Xifeng Ren Qin Wang Chang-Ling Zou Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Broadband Wireless Communication and Sensor Network Technology Key Laboratory of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China CAS Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China State Key Laboratory of Quantum Optics and Quantum Optics Devices and Institute of Opto-Electronics Shanxi University Taiyuan 030006 China

An on-chip multigrating device is proposed to interface single atoms and integrated photonic circuits, by guiding and focusing lasers to the area ∼10 μm above the chip for trapping, state manipulation, and readout of single rubidium atoms. For the optical dipole trap, two 850-nm laser beams are diffracted and overlapped to form the lattice of a single-atom dipole trap, with the diameter of the optical dipole trap being around 2.7 μm. Similar gratings are designed for guiding a 780-nm probe laser to excite and also collect the fluorescence of Rb87 atoms. Such a device provides a compact solution for future applications of single atoms, including the single-photon source, single-atom quantum register, and single-atom quantum sensor.

关键词： Atom optics Photonics

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Proposal for low-power atom trapping on a GaN-on-sapphire chip

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Physical Review A 2022年第3期106卷 033104-033104页

作者： Aiping Liu Lei Xu Xin-Biao Xu Guang-Jie Chen Pengfei Zhang Guo-Yong Xiang Guang-Can Guo Qin Wang Chang-Ling Zou Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Broadband Wireless Communication and Sensor Network Technology Key Laboratory of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China CAS Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China State Key Laboratory of Quantum Optics and Quantum Optics Devices and Institute of Opto-Electronics Shanxi University Taiyuan 030006 China

Hybrid photon-atom integrated circuits, which include photonic microcavities and trapped single neutral atoms in their evanescent field, have great potential for quantum information processing. In this platform, the atoms provide single-photon nonlinearity and long-lived memory, which are complementary to the excellent passive photonic devices in conventional quantum photonic circuits. In this work, we propose a stable platform for realizing hybrid photon-atom circuits based on an unsuspended photonic chip. By introducing high-order modes in the microring, a feasible evanescent-field trap potential well ∼0.26mK could be obtained by only 10-mW-level power in the cavity, compared with the 100-mW-level power required in the scheme based on fundamental modes. Based on our scheme, stable single-atom trapping with relatively low laser power is feasible for future studies on high-fidelity quantum gates, single-photon sources, and many-body quantum physics based on a controllable atom array in a microcavity.

关键词： Cooling & trapping Photonics Relativistic & quantum electrodynamic effects in atoms, molecules,& ions

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Experimental measurement-device-independent quantum key distribution with uncharacterized sources

Experimental measurement-device-independent quantum key dist...

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OSA Quantum 2.0 Conference, QUANTUM 2020

作者： Wang, Qin Institute of quantum information and technology Nanjing University of Posts and Telecommunications Nanjing210003 China "Broadband Wireless Communication and Sensor Network Technology" Key Lab of Ministry of Education NUPT Nanjing210003 China "Telecommunication and Networks" National Engineering Research Center NUPT Nanjing210003 China

We carry out a proof-of-principle demonstration of three-state uncharacterized measurement-device-independent quantum key distribution over 170 km, achieving the longest transmission distance under the same security l... 详细信息

ISBN: (纸本)9781557528209

关键词： Quantum cryptography

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Hierarchical Deep Reinforcement Learning for Age-of-Information Minimization in IRS-aided and wireless-powered wireless networks

arXiv

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arXiv 2022年

作者： Gong, Shimin Cui, Leiyang Gu, Bo Lyu, Bin Hoang, Dinh Thai Niyato, Dusit The School of Intelligent Systems Engineering Sun Yat-sen University Shenzhen518055 China Key Laboratory of Ministry of Education in Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications China The School of Electrical and Data Engineering University of Technology Sydney Australia School of Computer Science and Engineering Nanyang Technological University Singapore

In this paper, we focus on a wireless-powered sensor network coordinated by a multi-antenna access point (AP). Each node can generate sensing information and report the latest information to the AP using the energy harvested from the AP’s signal beamforming. blueWe aim to minimize the average age-of-information (AoI) by adapting the nodes’ transmission scheduling and the transmission control strategies jointly. To reduce the transmission delay, an intelligent reflecting surface (IRS) is used to enhance the channel conditions by controlling the AP’s beamforming bluevector and the IRS’s phase shifting bluematrix. blueConsidering dynamic data arrivals at different sensing nodes, we propose a hierarchical deep reinforcement learning (DRL) framework to bluefor AoI minimization in two steps. The users’ transmission scheduling is firstly determined by the outer-loop DRL approach, e.g. the DQN or PPO algorithm, and then the inner-loop optimization is used to adapt either the uplink information transmission or downlink energy transfer to all nodes. A simple and efficient approximation is also proposed to reduce the blueinner-loop rum time overhead. Numerical results verify that the hierarchical learning framework outperforms typical baselines in terms of the average AoI and proportional fairness among different nodes. © 2022, CC BY.

关键词： Reinforcement learning

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