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南水北调东线沿线湖泊生态环境面临的挑战与保护对策

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湖泊科学 2024年第5期36卷 1289-1302页

作者：张运林蔡永久彭凯龚志军罗菊花周永强魏佳豪贺诗文李娜薛滨中国科学院南京地理与湖泊研究所湖泊与流域水安全重点实验室南京210008 中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室太湖湖泊生态系统研究站南京210008 中国科学院大学北京100049 中国科学院大学南京学院南京211135

南水北调东线工程横跨长江、淮河、黄河和海河四大流域,通过京杭大运河和输水渠道自南向北连通了高邮湖、洪泽湖、骆马湖、南四湖、东平湖和北大港水库等湖泊和水库,向黄淮海平原东部、胶东地区以及津冀地区提供生产生活生态用水。沿线... 详细信息

南水北调东线工程横跨长江、淮河、黄河和海河四大流域,通过京杭大运河和输水渠道自南向北连通了高邮湖、洪泽湖、骆马湖、南四湖、东平湖和北大港水库等湖泊和水库,向黄淮海平原东部、胶东地区以及津冀地区提供生产生活生态用水。沿线调蓄湖泊是南水北调东线工程的关键节点和调蓄池,是改善输水水质的净化器和重要“绿肾”,对保障输供水安全至关重要。近年来,在生态文明建设和打好碧水保卫战的大背景下,南水北调东线沿线调蓄湖泊治理保护取得明显成效,水环境质量总体上呈改善趋势,但在快速气候变化和高强度人类活动的双重影响下,沿线湖泊流域水污染防控、水环境治理和水生态保护修复仍面临严峻挑战。本文从水量调蓄与水质净化、饮用水安全保障、农业灌溉与粮食安全、生物多样性保护、航运与大运河水文化等方面系统阐述了南水北调东线沿线湖泊的主要生态服务功能,深入剖析了水质超标风险、湖泊富营养化、藻类水华暴发以及草型生态系统退化等生态环境问题,提出了水环境质量持续改善以及水生态系统完整性、稳定性和持续性稳步提升的保护策略,助力南水北调东线水安全保障国家战略。

关键词：湖泊调蓄富营养化藻类水华饮用水安全策略与对策

DIUN:Deeper Inception U-Network for Recovering Partial Pixelated Images

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Journal of Systems Science and Information 2022年第2期10卷 193-202页

作者： Hufei YU shiwen he Min ZHANG Wenwu XIE Yan TANG School of Computer Science and Engineering Central South UniversityChangsha 410083China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 210096China Hunan Post and Telecommunication College Changsha 410083China Department of Information Science and Engineering College of Hunan Institute of Science and TechnologyYueyang 414006China

In our daily life,it is nothing strange to see pixelated images that are spoiled artificially to hide certain information for protecting privacy or pixelated deliberately to cover up bad behaviors even *** prevent these phenomena and recover the true information from pixelated images,it is meaningful to research an effective reconstruction method for recovering pixelated *** paper aims at recovering the artificial partial pixelated images via deep learning(DL).To abstract more abundant features and enhance the repair ability of DL model,we propose a new DL structure,called deeper inception U-Net,to act as the generator of a generative adversarial *** combine the feature loss with structural similarity index measure loss as the context loss to minimize the distance between feature maps of clear images and the generated images,which helps to improve the quality of repair *** obtaining inception features,we use fusion layer to adaptively learn featuresin each inception *** evaluate the performance of our model,we introduce a new home dataset that contains 10174 clear home images with corresponding pixelated images.A series of experiments show that our model has ability to rebuild pixelated images.

关键词： pixelated image repair deep learning generative adversarial network

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胸外科基础研究的现状与展望

中华实验外科杂志 2024年第8期41卷 1670-1673页

作者：刁明炘武世豪汪杨威何世文廖永德华中科技大学同济医学院附属协和医院胸外科武汉430022

目前肺癌的发病率和死亡率位居第一,国内食管癌患者人数占全世界一半以上,胸外科作为这两种疾病的诊治一线正面临前所未有的挑战。以手术为主,化疗、靶向治疗、免疫治疗为辅的治疗模式在不断的更新迭代,随着"空间单细胞多组学"、"更高... 详细信息

目前肺癌的发病率和死亡率位居第一,国内食管癌患者人数占全世界一半以上,胸外科作为这两种疾病的诊治一线正面临前所未有的挑战。以手术为主,化疗、靶向治疗、免疫治疗为辅的治疗模式在不断的更新迭代,随着"空间单细胞多组学"、"更高层次的多模态"、"更深层次的学科交叉融合"等概念的出现,为胸外科的基础研究带来了机遇和挑战。我们胸外科医师应该在时代的潮流中,激流勇进,迎难而上,在基础研究领域深耕细作,促进基础向临床的转化,为胸外科的发展添砖加瓦。

关键词：胸外科基础研究胸部肿瘤

构建无线网络内生智能通信验证系统的挑战与方法

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移动通信 2024年第7期48卷 2-14页

作者：何世文董浩磊彭石林刘文超张晓宇朱小亮中南大学计算机学院湖南长沙410083 紫金山实验室江苏南京211111 天翼数字生活科技有限公司上海200072 新疆大学软件学院新疆乌鲁木齐830049

随着人工智能和深度学习在计算机视觉、机器人、医疗等领域的成功应用,无线网络智能化成为下一代无线通信发展的关键技术之一。因此探讨构建无线网络内生智能通信验证系统所面临的关键技术挑战与部署方案。采用网络功能虚拟化、软件定... 详细信息

随着人工智能和深度学习在计算机视觉、机器人、医疗等领域的成功应用,无线网络智能化成为下一代无线通信发展的关键技术之一。因此探讨构建无线网络内生智能通信验证系统所面临的关键技术挑战与部署方案。采用网络功能虚拟化、软件定义网络、容器和微服务等先进技术,以Kubernetes为平台基座,以信号处理时间轴为主线,以计算、网络、数据及无线资源等池化管理为核心,构建集无线数据采集与分析、网络状态建模与预测、模型部署与应用、数据要素动态监控与可视的无线网络内生智能通信验证系统,使该系统具备实时数据采析、全面地理解和监控无线网络状态,实现无线通信与网络中数据-算力-资源灵活、敏捷、智能的编排与管理、传输策略智能调优等内生智能通信技术测试验证的目标。

关键词：内生智能无线网络验证系统

Forward link outage performance of aeronautical broadband satellite communications

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Frontiers of Information Technology & Electronic Engineering 2021年第6期22卷 790-801页

作者： Huaicong KONG Min LIN shiwen he Xiaoyu LIU Jian OUYANG Weiping ZHU College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Computer Science and Engineering Central South UniversityChangsha 410083China Purple Mountain Laboratories Nanjing 210096China Department of Electrical and Computer Engineering Concordia UniversityMontrealQC H3G 1M8Canada

High-throughput satellites(HTSs) play an important role in future millimeter-wave(mm Wave) aeronautical communication to meet high speed and broad bandwidth requirements. This paper investigates the outage performance of an aeronautical broadband satellite communication system’s forward link, where the feeder link from the gateway to the HTS uses free-space optical(FSO) transmission and the user link from the HTS to aircraft operates at the mm Wave band. In the user link, spot beam technology is exploited at the HTS and a massive antenna array is deployed at the aircraft. We first present a location-based beamforming(BF) scheme to maximize the expected output signal-to-noise ratio(SNR) of the forward link with the amplify-and-forward(AF) protocol,which turns out to be a phased array. Then, by supposing that the FSO feeder link follows Gamma-Gamma fading whereas the mm Wave user link experiences shadowed Rician fading, we take the influence of the phase error into account, and derive the closed-form expression of the outage probability(OP) for the considered system. To gain further insight, a simple asymptotic OP expression at a high SNR is provided to show the diversity order and coding gain. Finally, numerical simulations are conducted to confirm the validity of the theoretical analysis and reveal the effects of phase errors on the system outage performance.

关键词： Aeronautical broadband satellite network Free-space optical(FSO)transmission High throughput mmWave communication Outage probability Phase error

Adversarial attacks and defenses for digital communication signals identification

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Digital Communications and Networks 2024年第3期10卷 756-764页

作者： Qiao Tian Sicheng Zhang shiwen Mao Yun Lin College of Computer Science and Technology Harbin Engineering UniversityHarbin150001China College of Information and Communication Engineering Harbin Engineering UniversityHarbin150000China Department of Electrical and Computer Engineering Auburn UniversityAuburnAL36849USA

As modern communication technology advances apace,the digital communication signals identification plays an important role in cognitive radio networks,the communication monitoring and management *** has become a promising solution to this problem due to its powerful modeling capability,which has become a consensus in academia and ***,because of the data-dependence and inexplicability of AI models and the openness of electromagnetic space,the physical layer digital communication signals identification model is threatened by adversarial *** examples pose a common threat to AI models,where well-designed and slight perturbations added to input data can cause wrong ***,the security of AI models for the digital communication signals identification is the premise of its efficient and credible *** this paper,we first launch adversarial attacks on the end-to-end AI model for automatic modulation classifi-cation,and then we explain and present three defense mechanisms based on the adversarial *** we present more detailed adversarial indicators to evaluate attack and defense ***,a demonstration verification system is developed to show that the adversarial attack is a real threat to the digital communication signals identification model,which should be paid more attention in future research.

关键词： Digital communication signals identification AI model Adversarial attacks Adversarial defenses Adversarial indicators

Stability Analysis of a Class of Nonlinear Fractional Differential Systems With Riemann-Liouville Derivative

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1883-1885页

作者： Ruoxun Zhang Shiping Yang shiwen Feng College of Teacher Education Xingtai UniversityXingtai 054001China College of Physics and Information Engineering Hebei Normal UniversityShijiazhuang 050016China

Dear Editor,This letter investigates the stability of n-dimensional nonlinear fractional differential systems with Riemann-Liouville *** using the Mittag-Leffler function,Laplace transform and the Gronwall-Bellman lemma,one sufficient condition is attained for the asymptotical stability of a class of nonlinear fractional differential systems whose order lies in(0,2).According to this theory,if the nonlinear term satisfies some conditions,then the stability condition for nonlinear fractional differential systems is the same as the ones for corresponding linear *** examples are provided to illustrate the applications of our result.

关键词： Liouville Riemann nonlinear

Unraveling the atomic interdiffusion mechanism of NiFe_(2_)O_(4)oxygen carriers during chemical looping CO_(2)conversion

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Carbon Energy 2024年第8期6卷 105-121页

作者： Da Song Yan Lin shiwen Fang Yang Li Kun Zhao Xinfei Chen Zhen Huang Fang he Zengli Zhao Hongyu Huang Fanxing Li Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhouChina School of Energy Science and Engineering University of Science and Technology of ChinaHefeiChina College of Mechanical and Electrical Engineering Zhongkai University of Agriculture and EngineeringGuangzhouChina College of Chemistry and Bioengineering Guilin University of TechnologyGuilinChina North Carolina State University RaleighNorth CarolinaUSA

By employing metal oxides as oxygen carriers,chemical looping demonstrates its effectiveness in transferring oxygen between reduction and oxidation environments to partially oxidize fuels into syngas and convert CO_(2)into ***,NiFe_(2_)O_(4)oxygen carriers have demonstrated remarkable efficiency in chemical looping CO_(2)***,the intricate process of atomic migration and evolution within the internal structure of bimetallic oxygen carriers during continuous high‐temperature redox cycling remains ***,the lack of a fundamental understanding of the complex ionic migration and oxygen transfer associated with energy conversion processes hampers the design of high‐performance oxygen ***,in this study,we employed in situ characterization techniques and theoretical calculations to investigate the ion migration behavior and structural evolution in the bulk of NiFe_(2_)O_(4)oxygen carriers during H2 reduction and CO_(2)/lab air oxidation *** discovered that during the H2 reduction step,lattice oxygen rapidly migrates to vacancy layers to replenish consumed active oxygen species,while Ni leaches from the material and migrates to the *** the CO_(2)splitting step,Ni migrates toward the core of the bimetallic oxygen carrier,forming Fe–Ni *** the air oxidation step,Fe–Ni migrates outward,creating a hollow structure owing to the Kirkendall effect triggered by the swift transfer of lattice *** metal atom migration paths depend on the oxygen transfer *** discoveries highlight the significance of regulating the release–recovery rate of lattice oxygen to uphold the structures and reactivity of oxygen *** work offers a comprehensive understanding of the oxidation/reduction‐driven atomic interdiffusion behavior of bimetallic oxygen carriers.

关键词： chemical looping CO_(2)splitting density functional theory in situ characterization ionic migration

A Tightly Coupled Dipole Array with Diverse Element Reflection Phases for RCS Reduction

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Chinese Journal of Electronics 2024年第2期33卷 449-455页

作者： Yuewen GOU Yikai CheN shiwen YANG University of Electronic Science and Technology of China

This paper proposes a novel low scattering tightly coupled dipole array(TCDA), aiming to reduce the radar cross section(RCS) of phased antenna arrays under a certain oblique incident wave. First, we build three types of antenna elements that exhibit similar radiation characteristics but diverse reflection phase differences based on the proposed theoretical analysis. The required reflection phase difference is achieved by using different dielectric superstrates for each antenna element. Then, by arranging the three types of subarrays next to each other, a low scattering TCDA(8 × 9) is designed. Meanwhile, a reference antenna array with a single type of antenna element is also constructed. To demonstrate the effectiveness of the proposed RCS reduction technique, simulated and measured results of the reference and proposed antenna array are compared. Both antenna arrays operate over the 6–18 GHz frequency band and can scan up to ±45° in the E-/H-planes. However, the proposed antenna array achieves a significant monostatic RCS reduction over 8–12 GHz, with a maximum reduction value of 7.55 d B. It indicates that this diverse element reflection phase technique is a good candidate for wideband RCS reduction.

关键词： Antenna measurements Phased arrays Dipole antennas Antenna theory Scattering Reflector antennas Reflection