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Communications in Urban Low-Altitude Drone Logistics Networks:Requirements,Solutions and Challenges
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作者 Duan Ruiyang Mao Yinian +1 位作者 Chen Jialong Song Jian 《China Communications》 2025年第9期37-47,共11页
Communications system has a signifi-cant impact on both operational safety and logisti-cal efficiency within low-altitude drone logistics net-works.Aiming at providing a systematic investiga-tion of real-world communi... Communications system has a signifi-cant impact on both operational safety and logisti-cal efficiency within low-altitude drone logistics net-works.Aiming at providing a systematic investiga-tion of real-world communication requirements and challenges encountered in Meituan UAV’s daily oper-ations,this article first introduces the operational sce-narios within current drone logistics networks and an-alyzes the related communication requirements.Then,the current communication solution and its inherent bottlenecks are elaborated.Finally,this paper explores emerging technologies and examines their application prospects in drone logistics networks. 展开更多
关键词 communication challenges communication requirements drone logistics low-altitude economy
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Fast Freight Takes Flight Robust governance and innovation are key to unlocking the full potential of low-altitude logistics
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作者 ji jing 《Beijing Review》 2025年第49期38-39,共2页
In the era of technology rapidly transforming logistics and logistical efficiency becoming a key economic driver,drones are emerging as a game-changing transport technology.Faster than planes,trains and trucks between... In the era of technology rapidly transforming logistics and logistical efficiency becoming a key economic driver,drones are emerging as a game-changing transport technology.Faster than planes,trains and trucks between nearby cities,drone logistics is becoming one of the fastest-growing sectors of the low-altitude economy. 展开更多
关键词 low altitude logistics transport technologyfaster fast freight robust governance technology transformation economic driver drones innovation
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Three-dimension collision-free trajectory planning of UAVs based on ADS-B information in low-altitude urban airspace 被引量:2
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作者 Chao DONG Yifan ZHANG +3 位作者 Ziye JIA Yiyang LIAO Lei ZHANG Qihui WU 《Chinese Journal of Aeronautics》 2025年第2期274-285,共12页
The environment of low-altitude urban airspace is complex and variable due to numerous obstacles,non-cooperative aircraft,and birds.Unmanned Aerial Vehicles(UAVs)leveraging environmental information to achieve three-d... The environment of low-altitude urban airspace is complex and variable due to numerous obstacles,non-cooperative aircraft,and birds.Unmanned Aerial Vehicles(UAVs)leveraging environmental information to achieve three-dimension collision-free trajectory planning is the prerequisite to ensure airspace security.However,the timely information of surrounding situation is difficult to acquire by UAVs,which further brings security risks.As a mature technology leveraged in traditional civil aviation,the Automatic Dependent Surveillance-Broadcast(ADS-B)realizes continuous surveillance of the information of aircraft.Consequently,we leverage ADS-B for surveillance and information broadcasting,and divide the aerial airspace into multiple sub-airspaces to improve flight safety in UAV trajectory planning.In detail,we propose the secure Sub-airSpaces Planning(SSP)algorithm and Particle Swarm Optimization Rapidly-exploring Random Trees(PSO-RRT)algorithm for the UAV trajectory planning in law-altitude airspace.The performance of the proposed algorithm is verified by simulations and the results show that SSP reduces both the maximum number of UAVs in the sub-airspace and the length of the trajectory,and PSO-RRT reduces the cost of UAV trajectory in the sub-airspace. 展开更多
关键词 Three-dimension trajectory planning of UAV Collision avoidance Sliding window ADS-B low-altitude urban airspace
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Fluid-based moderate collision avoidance for UAV formation in 3-D low-altitude environments 被引量:1
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作者 Menghua ZHANG Honglun WANG +5 位作者 Zhiyu LI Yanxiang WANG Xianglun ZHANG Qiang TANG Shichao MA Jianfa WU 《Chinese Journal of Aeronautics》 2025年第6期533-551,共19页
Aiming to address the Unmanned Aerial Vehicle(UAV) formation collision avoidance problem in Three-Dimensional(3-D) low-altitude environments where dense various obstacles exist, a fluid-based path planning framework n... Aiming to address the Unmanned Aerial Vehicle(UAV) formation collision avoidance problem in Three-Dimensional(3-D) low-altitude environments where dense various obstacles exist, a fluid-based path planning framework named the Formation Interfered Fluid Dynamical System(FIFDS) with Moderate Evasive Maneuver Strategy(MEMS) is proposed in this study.First, the UAV formation collision avoidance problem including quantifiable performance indexes is formulated. Second, inspired by the phenomenon of fluids continuously flowing while bypassing objects, the FIFDS for multiple UAVs is presented, which contains a Parallel Streamline Tracking(PST) method for formation keeping and the traditional IFDS for collision avoidance. Third, to rationally balance flight safety and collision avoidance cost, MEMS is proposed to generate moderate evasive maneuvers that match up with collision risks. Comprehensively containing the time and distance safety information, the 3-D dynamic collision regions are modeled for collision prediction. Then, the moderate evasive maneuver principle is refined, which provides criterions of the maneuver amplitude and direction. On this basis, an analytical parameter mapping mechanism is designed to online optimize IFDS parameters. Finally, the performance of the proposed method is validated by comparative simulation results and real flight experiments using fixed-wing UAVs. 展开更多
关键词 Unmanned aerial vehicle Formation collision avoidance:3-D low-altitude environments Interfered fluid dynamical system 3-D dynamic collision region
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一类调制耦合logistics模型的动力学行为
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作者 李亚男 刘娜 余志恒 《数学进展》 北大核心 2025年第3期545-570,共26页
本文主要研究了一类调制耦合logistics模型的动力学行为.我们首先运用多项式完全判别系统理论处理相关高阶半代数系统,并给出了该模型在各个不动点处的拓扑分类及其局部稳定性.其次,利用中心流形定理,我们分别给出该模型在不同非双曲情... 本文主要研究了一类调制耦合logistics模型的动力学行为.我们首先运用多项式完全判别系统理论处理相关高阶半代数系统,并给出了该模型在各个不动点处的拓扑分类及其局部稳定性.其次,利用中心流形定理,我们分别给出该模型在不同非双曲情形下不动点附近发生跨临界和超临界倍周期分岔的参数条件.此外,我们还证明了该模型具有Marotto意义下的混沌.最后,借助Maple 2023和Matlab R2019a,我们对该模型的动力学行为进行数值模拟,以进一步验证前述理论结果的正确性. 展开更多
关键词 耦合logistics模型 多项式完全判别系统 分岔 Marotto混沌
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Towards a Low-Altitude Aerial Intelligent Network: Vision, Challenges, and Key Technologies
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作者 Huang Yuhong Ding Haiyu +6 位作者 Chen Weiyan Kong Luting Deng Wei Li Xin Liu Yang Wang Guizhen Liu Liang 《China Communications》 2025年第9期1-21,共21页
The large-scale development of the lowaltitude economy imposes increasingly stringent requirements on the supporting information infrastructure,necessitating the establishment of a low-altitude intelligent network(LAI... The large-scale development of the lowaltitude economy imposes increasingly stringent requirements on the supporting information infrastructure,necessitating the establishment of a low-altitude intelligent network(LAIN)with wide-area communication,high-precision navigation,and efficient supervision capabilities.Benefiting from its broad coverage,high reliability,and large bandwidth,the 5G cellular network serves as a critical foundation for LAIN construction.However,conventional cellular networks are primarily designed for two-dimensional terrestrial scenarios,and thus face significant limitations in coverage and interference resistance within complex three-dimensional low-altitude environments.To address the unique demands of LAIN applications,key challenges must be tackled,including achieving seamless three-dimensional coverage,mitigating interference in multi-dimensional network deployments,and ensuring stringent requirements for service quality and security supervision.This paper proposes an integrated LAIN architecture characterized by the convergence of communication,navigation,sensing,and management,enhanced with artificial intelligence and security mechanisms to improve overall system intelligence and resilience.Furthermore,this paper conducts an in-depth analysis of the critical challenges in LAIN deployment,explores enabling technologies to address these issues,and offers insights into the future development direction of low-altitude intelligent networks. 展开更多
关键词 cellular network 5G 5G-A low-altitude aerial intelligent network low-altitude economy mobile communication
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多因素Logistic回归模型联合ROC曲线预测重症感染患者美罗培南血药浓度不达标的风险
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作者 李淼 黄兴振 《中国处方药》 2026年第2期65-70,共6页
目的构建重症感染患者美罗培南血药浓度不达标风险的预测模型,为临床重症感染患者美罗培南的初始给药方案提供用药参考。方法选取广西某三级甲等医院2021年1月至2024年12月收治的436例疑似或确诊为脓毒血症需使用美罗培南抗感染治疗,同... 目的构建重症感染患者美罗培南血药浓度不达标风险的预测模型,为临床重症感染患者美罗培南的初始给药方案提供用药参考。方法选取广西某三级甲等医院2021年1月至2024年12月收治的436例疑似或确诊为脓毒血症需使用美罗培南抗感染治疗,同时进行血药浓度监测的住院患者作为研究对象。根据美罗培南血药浓度检测结果将患者分为达标组和未达标组,分析两组患者一般资料及临床检验指标,将差异有统计学意义的指标纳入多因素Logistic回归模型分析影响美罗培南血药浓度的因素,并构建重症感染患者美罗培南血药浓度不达标风险的预测模型,采用受试者工作特征(ROC)曲线评价该模型的预测效能。结果高龄、高Cr、低ALB及合并使用利尿剂的重症感染患者即使按常规剂量使用美罗培南,也更易出现暴露不足,需考虑个体化增量或延长输注。年龄、Cr、ALB及合并利尿剂预测重症感染患者美罗培南血药浓度不达标风险的灵敏度分别为69.20%、89.70%、58.10%和76.10%,特异度分别为65.80%、69.90%、66.50%和42.30%,曲线下面积(AUC)分别为0.718、0.858、0.655和0.592,四者联合预测的灵敏度为80.30%,特异度为83.10%,AUC为0.900,合并使用利尿剂、年龄、Cr和ALB联合预测美罗培南血药浓度不达标风险的效能优于任一指标单独预测(P<0.05)。结论年龄、Cr、ALB、合并使用利尿剂联合预测重症感染患者美罗培南血药浓度不达标风险具有较好的效能。高龄、高Cr、低ALB及合并使用利尿剂使重症患者即使按常规剂量也更易出现暴露不足,需考虑个体化增量或延长输注。 展开更多
关键词 美罗培南 血药浓度 logistIC回归 ROC曲线
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Is digital transformation boosting green innovation in logistics enterprises?Evidence from listed firms in China’s logistics industry
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作者 Jun Li Xi Chen Liang Wan 《中国科学技术大学学报》 北大核心 2025年第1期18-30,17,I0001,共15页
In the era of green logistics,digital transformation has become an effective means for the logistics industry’s high-quality development.Using listed companies in China’s logistics industry from 2010 to 2021 as the ... In the era of green logistics,digital transformation has become an effective means for the logistics industry’s high-quality development.Using listed companies in China’s logistics industry from 2010 to 2021 as the research samples,this paper conducts an empirical test on the impact of the digital transformation of logistics enterprises on their green in-novation.Specifically,enterprise digital transformation indicators are constructed through the text analysis method,and the fixed-effects model is applied for analysis.The results indicate that the digital transformation of logistics enterprises has a significant promoting effect on their green innovation;the promoting effect of the digital transformation of logistics enterprises on green innovation is primarily achieved by easing corporate financing constraints and reducing corporate en-vironmental uncertainty;and the impact of digital transformation on green innovation is geographically heterogeneous. 展开更多
关键词 DIGITALIZATION logistics enterprises green innovation
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Exploring the Development Model of UAVs Empowered by the Low-Altitude Economy
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作者 Fan Shi Yuyao Zu 《Journal of Electronic Research and Application》 2025年第4期135-140,共6页
The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,arti... The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,artificial intelligence,blockchain technology,etc.with the real economy,facilitate the development of advanced manufacturing,and consider UAVs as an important breakthrough,providing significant opportunities for the development of the UAV industry.Therefore,this article takes the current status of the UAV industry development as a starting point,analyzes the exploration and practice of the UAV development model based on the low-altitude economy,and discusses strategic suggestions to promote the development of UAVs empowered by the low-altitude economy.Through analysis,this article aims to provide theoretical reference and practical guidance for promoting the sustainable development of the UAV industry under the wave of the low-altitude economy. 展开更多
关键词 low-altitude economy UAV Development model
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Exploring the Development Model of UAVs Empowered by the Low-Altitude Economy
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作者 Fan Shi Yuyao Zu 《Journal of Electronic Research and Application》 2025年第5期111-116,共6页
The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,arti... The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,artificial intelligence,blockchain technology,etc.with the real economy,facilitate the development of advanced manufacturing,and consider unmanned aerial vehicles(UAVs)as an important breakthrough,providing significant opportunities for the development of the UAV industry.Therefore,this article takes the current status of the UAV industry development as a starting point,analyzes the exploration and practice of the UAV development model based on the low-altitude economy,and discusses strategic suggestions to promote the development of UAVs empowered by the low-altitude economy.Through analysis,this article aims to provide theoretical references and practical guidance for promoting the sustainable development of the UAV industry under the wave of the low-altitude economy. 展开更多
关键词 low-altitude economy UAV Development model
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Mechanism and Implementation Panths of Low-Altitude Economy in Promoting Transformation and Upgrading of Tourism Industry in Zhejiang Province
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作者 Zhenzi GUO 《Asian Agricultural Research》 2025年第8期13-15,26,共4页
Taking Zhejiang Province as an example,this paper explores the mechanisms and implementation pathways through which the low-altitude economy drives the transformation and upgrading of the tourism industry.It finds tha... Taking Zhejiang Province as an example,this paper explores the mechanisms and implementation pathways through which the low-altitude economy drives the transformation and upgrading of the tourism industry.It finds that the low-altitude economy can effectively promote the development of high-end and diversified tourism in Zhejiang by innovating tourism formats,optimizing resource allocation,and enhancing tourist experiences.Besides,it analyzes the current development status of the low-altitude economy in Zhejiang and its potential for integration with tourism,revealing specific enabling pathways for tourism transformation,including low-altitude sightseeing,aviation tourism,and low-altitude sports.Finally,it proposes policy recommendations such as strengthening policy support,enhancing infrastructure development,and cultivating market entities.The findings aim to provide theoretical references and practical guidance for the high-quality development of tourism in Zhejiang Province. 展开更多
关键词 low-altitude ECONOMY Transformation and upgrading of the tourism industry Action MECHANISM IMPLEMENTATION path ZHEJIANG Province
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Agile Coverage for Low-Altitude Aerial Intelligent Networks:A Blended Hyper-Cellular Solution
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作者 Zhou Sheng Xie Bowen +3 位作者 Shen Daohong Feng Wei Jiang Zhiyuan Niu Zhisheng 《China Communications》 2025年第9期22-36,共15页
This paper proposes a novel blended hyper-cellular architecture for low-altitude aerial intelligent networks(LAINs)to provide agile coverage tailored to active air routes and takeoff/landing spots.Traditional cellular... This paper proposes a novel blended hyper-cellular architecture for low-altitude aerial intelligent networks(LAINs)to provide agile coverage tailored to active air routes and takeoff/landing spots.Traditional cellular networks struggle to meet the dynamic demands of low-altitude UAV communications due to their rigid structures.The hyper-cellular network(HCN)architecture separates control and traffic coverage,enabling flexible and energy-efficient operations.The key components include control base stations(CBSs)for wide-area signaling coverage and traffic base stations(TBSs)that can be dynamically activated based on traffic demands.The proposed solution also integrates space information networks(SINs)to enhance the coverage efficiency.Key technologies such as all-G CBS using RISC-V architecture,AI-powered radio maps for low-altitude environments,and agile TBS coverage adaptation are introduced with some preliminary studies.These designs aim to address challenges like mobility management,interference coordination,and the need for real-time spectrum sharing in blended satellite-terrestrial networks.The proposed solution offers a scalable and agile framework to support the rapidly growing demand for reliable,low-latency,and high-capacity UAV communications in urban environments. 展开更多
关键词 coverage optimization hyper-cellular low-altitude aerial networks space-air-ground integrated networks
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IACO优化Logistic混沌序列在无线传感器网络布局中应用
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作者 陈静 《技术与市场》 2026年第1期33-36,共4页
为了压缩通信成本并减少传感器个数,采用蚁群算法的优化路径。标准混沌序列算法存在分簇随机的问题,为此引入混沌算子,提出一种利用改进蚁群算法(IACO)对Logistic混沌序列方法进行改进,并成功应用于无线传感器网络布局中。研究结果表明... 为了压缩通信成本并减少传感器个数,采用蚁群算法的优化路径。标准混沌序列算法存在分簇随机的问题,为此引入混沌算子,提出一种利用改进蚁群算法(IACO)对Logistic混沌序列方法进行改进,并成功应用于无线传感器网络布局中。研究结果表明:随着迭代周期的增加,通信成本降低,可有效防止出现局部最佳的现象。相比贪心算法(Greedy)与IACO方法,改进蚁群算法-最长公共子序列算法(IACO-LCS)的通信成本显著降低,达到目标收益。该研究对提高无线传感器布局优化能力具有一定的理论指导意义。 展开更多
关键词 无线传感器 布局优化 改进蚁群算法 logistIC混沌序列 搜索速度
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基于CT血管造影参数的LASSO-logistic回归模型对颅内小动脉瘤破裂风险的预测价值
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作者 程箫 刘亚辉 冉雅菲 《实用医技杂志》 2026年第1期12-16,I0004,共6页
目的探讨计算机断层扫描血管造影(CTA)参数在评估颅内小动脉瘤破裂风险中的应用价值。方法回顾性分析2022年1月至2024年12月于郑州市第二人民医院确诊的92例颅内小动脉瘤患者资料,根据患者就诊时是否伴有急性蛛网膜下腔出血的临床表现... 目的探讨计算机断层扫描血管造影(CTA)参数在评估颅内小动脉瘤破裂风险中的应用价值。方法回顾性分析2022年1月至2024年12月于郑州市第二人民医院确诊的92例颅内小动脉瘤患者资料,根据患者就诊时是否伴有急性蛛网膜下腔出血的临床表现及影像学证据,分为破裂组(28例)和未破裂组(64例)。收集患者基线资料及CTA参数,采用最小绝对收缩和选择算法(LASSO)回归筛选变量,logistic回归构建预测模型。结果单因素分析结果显示,破裂组患者在高血压病史(60.7%与37.5%;χ^(2)=4.249,P=0.039)、脑血管病家族史(21.4%与6.2%;χ^(2)=4.632,P=0.031)、血管分叉部动脉瘤(53.6%与31.2%;χ^(2)=4.117,P=0.042)、存在异常搏动点(39.3%与10.9%;χ^(2)=9.947,P=0.002)、后循环区动脉瘤(32.1%与14.1%;χ^(2)=4.046,P=0.044)、瘤高与载瘤动脉直径比(SR)值(1.71±0.29与1.52±0.30;t=2.823,P=0.006)、动脉瘤角度(67.82°±10.98°与62.78°±10.86°;t=2.041,P=0.044)及子囊存在(28.6%与10.9%;χ^(2)=4.439,P=0.035)等指标均显著高于未破裂组;破裂组受试者的瘤径比(AR)值(1.83±0.32与1.57±0.29;t=3.834,P<0.001)亦明显更高。经LASSO回归分析,筛选出9个具有预测价值的变量,包括高血压病史、脑血管病家族史、血管分叉部动脉瘤、存在异常搏动点、后循环区动脉瘤、AR值、SR值、动脉瘤角度、子囊存在。进一步logistic回归分析结果显示,后循环区动脉瘤[OR(95%CI)=2.740(1.187,6.328)]、AR值[OR(95%CI)=3.102(1.106,8.697)]、动脉瘤角度[OR(95%CI)=3.846(1.074,13.766)]及子囊存在[OR(95%CI)=3.865(1.105,13.524)]等因素与颅内小动脉破裂风险独立相关(均P<0.05)。结论颅内小动脉瘤破裂主要受后循环区动脉瘤、AR值、动脉瘤角度及子囊存在等因素的影响,LASSO-logistic回归可用于预测颅内小动脉瘤破裂风险。 展开更多
关键词 颅内动脉瘤 CT血管成像 最小绝对收缩和选择算法 logistIC回归
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Integrated Sensing and Communications Network Design and Key Technologies for Low-Altitude Economy
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作者 Ma Dingyou Tang Jun +3 位作者 Zhang Qixun Wei Zhiqing Gao Feifei Feng Zhiyong 《China Communications》 2025年第9期81-102,共22页
With the rapid growth of the low-altitude economy,the demand for typical low-altitude ap-plications has accelerated the advancement of inte-grated sensing and communications(ISAC)networks.This paper begins by analyzin... With the rapid growth of the low-altitude economy,the demand for typical low-altitude ap-plications has accelerated the advancement of inte-grated sensing and communications(ISAC)networks.This paper begins by analyzing representative ap-plication scenarios to clarify the core requirements of the low-altitude economy for modern ISAC net-works.By investigating the distinctive characteris-tics of ISAC networks in low-altitude environments,it presents a comprehensive analysis of key challenges and identifies four major issues:challenges in pre-cise target detection,interference management,in-consistent sensing and communication coverage,and the complexity of air-ground coordination and han-dover.Based on fundamental theories and principles,the paper proposes corresponding solutions,encom-passing advanced technologies for precise target de-tection and recognition,high-reliability networked de-tection,robust interference management,and seamless air-ground collaboration.These solutions aim to es-tablish a solid foundation for the future development of intelligent low-altitude networks and ensure effec-tive support for emerging applications. 展开更多
关键词 integrated sensing and communications interference management low-altitude economy target detection
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Effectiveness of Logistics Management Information System (LMIS) in Improving the Availability of Essential Medicines and Medical Supplies in Public Hospitals in Zambia: A Cross-Sectional Study
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作者 Aubrey Kanyika Steward Mudenda +4 位作者 Victor Daka Nayuda Kaonga Chitundu Mbao Diana K. Mwaba Scott Kaba Matafwali 《Pharmacology & Pharmacy》 2025年第2期61-72,共12页
Background: The availability of essential medicines and medical supplies is crucial for effectively delivering healthcare services. In Zambia, the Logistics Management Information System (LMIS) is a key tool for manag... Background: The availability of essential medicines and medical supplies is crucial for effectively delivering healthcare services. In Zambia, the Logistics Management Information System (LMIS) is a key tool for managing the supply chain of these commodities. This study aimed to evaluate the effectiveness of LMIS in ensuring the availability of essential medicines and medical supplies in public hospitals in the Copperbelt Province of Zambia. Materials and Methods: From February to April 2022, a cross-sectional study was conducted in 12 public hospitals across the Copperbelt Province. Data were collected using structured questionnaires, checklists, and stock control cards. The study assessed LMIS availability, training, and knowledge among pharmacy personnel, as well as data accuracy, product availability, and order fill rates. Descriptive statistics were used to analyse the data. Results: All surveyed hospitals had LMIS implemented and were using eLMIS as the primary LMIS. Only 47% and 48% of pharmacy personnel received training in eLMIS and Essential Medicines Logistics Improvement Program (EMLIP), respectively. Most personnel demonstrated good knowledge of LMIS, with 77.7% able to log in to eLMIS Facility Edition, 76.6% able to locate stock control cards in the system, and 78.7% able to perform transactions. However, data accuracy from physical and electronic records varied from 0% to 60%, and product availability ranged from 50% to 80%. Order fill rates from Zambia Medicines and Medical Supplies Agency (ZAMMSA) were consistently below 30%. Discrepancies were observed between physical stock counts and eLMIS records. Conclusion: This study found that most hospitals in the Copperbelt Province of Zambia have implemented LMIS use. While LMIS implementation is high in the Copperbelt Province of Zambia, challenges such as low training levels, data inaccuracies, low product availability, and order fill rates persist. Addressing these issues requires a comprehensive approach, including capacity building, data quality improvement, supply chain coordination, and investment in infrastructure and human resources. Strengthening LMIS effectiveness is crucial for improving healthcare delivery and patient outcomes in Zambia. 展开更多
关键词 logistics Management Information System Essential Medicines Medical Supplies Supply Chain Management Zambia
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Global Competition and Urban Strategies:A Comparison of Low-Altitude Economy Models and the Shanghai Approach
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作者 WANG Youzhi 《国际大都市发展研究(中英文)》 2025年第3期21-41,共21页
As low-altitude airspace becomes increasingly accessible and eVTOL(electric vertical take-off and landing)technologies advance,the low-altitude economy has emerged as a transformative frontier in urban mobility and in... As low-altitude airspace becomes increasingly accessible and eVTOL(electric vertical take-off and landing)technologies advance,the low-altitude economy has emerged as a transformative frontier in urban mobility and industrial restructuring.Although countries face comparable technological opportunities,their development paths diverge significantly.This divergence is shaped not only by policy choices and innovation capacity but also by underlying differences in institutional architectures,resource configurations,and implementation mechanisms.This paper proposes a Development Path Evolution Model grounded in four structural elements:technological capability,institutional systems,infrastructure,and application scenarios.Based on this framework,the study identifies three archetypal path types(technology-led,institution-led,and scenario-driven)and empirically validates the model through comparative case studies of the United States,Europe,and Japan.Applying the model to China reveals a distinct"hybrid scenario-driven path",characterized by demand-responsive pilots,decentralized institutional flexibility,and strong engineering capacity.Using Shanghai as a representative case,the study outlines five strategic levers to guide its transition from a localized pilot zone to a platform-based governance hub with national and international relevance.The research contributes to theoretical understanding of path differentiation in emerging industries and provides actionable insights for developing economies with strong mobilization capacity and industrial ecosystems. 展开更多
关键词 low-altitude economy(LAE) development path evolution urban air mobility scenario-driven trajectory Shanghai strategy
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A Wideband High-Gain Antenna for Low-Altitude UAV Airspace Control
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作者 Bing Yu Xiaoxin Yang +2 位作者 Fei Liu Jiang Shang Yan Li 《Instrumentation》 2025年第3期88-96,共9页
This paper proposes a portable broadband high-gain antenna for unmanned aerial vehicle(UAV)low-altitude control,operating within the dedicated remotely piloted aircraft system(RPAS)band(5.03–5.91 GHz).The total size ... This paper proposes a portable broadband high-gain antenna for unmanned aerial vehicle(UAV)low-altitude control,operating within the dedicated remotely piloted aircraft system(RPAS)band(5.03–5.91 GHz).The total size of the antenna is 240×240×187 mm3.It uses a printed log-periodic dipole antenna(PLPDA)as feed,and a four-layer frequency selective surface(FSS)cascaded as radome to enhance gain.Experimental results demonstrate that the antenna gain ranges from 10.1 to 15.9 dB and the half-power beam width(HPBW,2θ0.5)<23°within the operation band.Compared to existing portable UAV low-altitude control systems,the proposed antenna achieves an average gain enhancement of 4.7 dB. 展开更多
关键词 unmanned aerial vehicle(UAV) low-altitude control ANTENNA frequency selective surface(FSS)
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Space-Air-Ground Collaborative Positioning,Navigation and Timing Architecture and Key Technologies for Low-Altitude Economy
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作者 Lu Mingquan Yao Zheng +2 位作者 Shen Yuan Li Xingxing Wang Zhipeng 《China Communications》 2025年第9期48-80,共33页
High-performance positioning,navigation and timing(PNT)service is critical to the safe flight of low-altitude aircraft and the effective management of low altitude traffic.In low-altitude economic sce-narios,the speci... High-performance positioning,navigation and timing(PNT)service is critical to the safe flight of low-altitude aircraft and the effective management of low altitude traffic.In low-altitude economic sce-narios,the specificity of massive unmanned aerial ve-hicle(UAV)flights and the complexity of low-altitude airspace traffic management impose stringent demand on the high-continuity,high-accuracy,real-time,and high-security PNT service.However,the current PNT service,which primarily relies on Global Navigation Satellite System(GNSS),Micro-Electro-Mechanical System Inertial Navigation System(MEMS INS),etc.,is completely inadequate to support the future needs of low-altitude economic development.In order to bridge the huge gap between existing capability and future demand,a three-layer PNT architecture based on the collaboration of space-based,air-based and ground-based PNT systems is proposed for low-altitude econ-omy.The space-based layer consists of high,medium even possible low orbit GNSS constellations,such as BeiDou Navigation Satellite System(BDS),for high-precision,high-security absolute positioning and tim-ing.The air-based layer leverages inter-aircraft links for high-reliability dynamic relative positioning.The ground-based layer includes pseudolite network,as well as 5G-advanced(5G-A)/6G network,for more comprehensive coverage and real-time positioning.To this end,it is imperative to make breakthroughs in key technologies,from systems to airborne terminal,in-cluding but not limited to high-precision anti-jamming GNSS signal processing,high-reliability relative po-sitioning,real-time pseudolite positioning,and high-efficient multi-source information fusion at airborne terminal,etc.Due to the moderate redundancy,hetero-geneous mechanism,and multiple coverage from mul-tiple PNT systems,the proposed layered PNT archi-tecture possesses high robustness and resilient.Addi-tionally,the integration of INS,LiDAR and vision etc.perception technologies can significantly enhance the PNT capability.As a result,the proposed three-layer PNT architecture enable greater autonomy for low-altitude aircraft and intelligent traffic management for massive UAV operations,and promoting the safe and efficient development of the low-altitude economy. 展开更多
关键词 low-altitude economy multi-source fu-sion positioning navigation and timing(PNT) space-air-ground collaborative architecture unmanned aerial vehicles(UAV)
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Bridging Emissions to Solutions: Enhancing Environmental Preservation through Green Inbound and Outbound Logistics
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作者 Apeksha Garg Sudha Vemaraju Marri Madhavi 《Journal of Environmental & Earth Sciences》 2025年第6期280-292,共13页
Logistics service providers significantly contribute to environmental degradation through improper waste disposal,hazardous packaging materials,excessive fuel consumption,and emissions.This study examines the impact o... Logistics service providers significantly contribute to environmental degradation through improper waste disposal,hazardous packaging materials,excessive fuel consumption,and emissions.This study examines the impact of green in-bound logistics and green outbound logistics on environmental,economic,and social performance of logistics companies using survey data from 221 Vietnamese logistics firms.Statistical analysis using Structural Equation Modeling revealed that green inbound logistics positively influences environmental and social performance while moderately affecting eco-nomic outcomes.In contrast,green outbound logistics demonstrates stronger effects on economic and environmental performance but exhibits limited impact on social dimensions.The measurement model showed strong reliability and validity(Cronbach's Alpha>0.70,robust Composite Reliability and Average Variance Extracted values),with excellent fit indices(Chi-Square/df=1.681,GFI=0.898,TLI=0.945,CFI=0.956,RMSEA=0.056).These findings highlight important distinctions between inbound and outbound green logistics impacts,offering valuable insights for an industry with currently low adoption rates of sustainable practices.The research demonstrates that implementing green logistics enhances both environmental preservation and business performance,providing compelling evidence for companies to accelerate their sustainability transition.By understanding these differential impacts,logistics firms can develop more tar-geted and effective sustainability strategies that optimize triple bottom line outcomes. 展开更多
关键词 Green logistics Environmental Performance Social Performance logistics Firms IGL OGL Carbon Emissions Energy Efficiency
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