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氧诱导条件下自发性视网膜色素变性模型rdf小鼠视网膜新生血管相关生长因子的表达和相互作用
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作者 刘梦园 谷蒙 +1 位作者 赵婧钰 张迁 《眼科新进展》 北大核心 2026年第1期13-17,共5页
目的探讨氧诱导条件下自发性视网膜色素变性模型rdf小鼠视网膜新生血管相关生长因子的表达和相互作用。方法选取7天龄C57BL/6J和rdf两种品系的小鼠各42只。将每种品系的小鼠分别随机分为常氧组与高氧组,分为4组:C57BL/6J常氧组、C57BL/6... 目的探讨氧诱导条件下自发性视网膜色素变性模型rdf小鼠视网膜新生血管相关生长因子的表达和相互作用。方法选取7天龄C57BL/6J和rdf两种品系的小鼠各42只。将每种品系的小鼠分别随机分为常氧组与高氧组,分为4组:C57BL/6J常氧组、C57BL/6J高氧组、rdf常氧组及rdf高氧组,每组18只;两种品系各预留6只(共12只)小鼠用于后续视网膜原代微血管内皮细胞的提取。利用高氧环境诱导建立视网膜病变模型作为高氧组小鼠,常氧组小鼠在正常大气环境中饲养。HE染色观察小鼠视网膜的结构变化,Western blot检测小鼠视网膜血管内皮生长因子(VEGF)、色素上皮衍生因子(PEDF)、缺氧诱导因子-1α及促红细胞生成素蛋白的表达,免疫共沉淀分析小鼠视网膜组织中PEDF与VEGF蛋白互作关系,免疫荧光染色分析不同品系小鼠原代视网膜内皮细胞中VEGF与PEDF的表达情况。结果HE染色结果显示,C57BL/6J常氧组小鼠视网膜各层结构排列整齐,未见新生血管内皮细胞突破内界膜;C57BL/6J高氧组小鼠视网膜结构紊乱,可见较多新生血管内皮细胞突破内界膜。rdf常氧组与高氧组小鼠视网膜各层结构均基本保持整齐,仅高氧组偶见新生血管内皮细胞突破内界膜。Western blot分析结果表明,无论在常氧还是高氧环境中,与C57BL/6J组相比,rdf组小鼠视网膜组织中促血管生成因子(VEGF、促红细胞生成素、缺氧诱导因子-1α)蛋白表达水平均显著降低;而血管抑制因子PEDF蛋白表达水平显著升高,差异均有统计学意义(均为P<0.05)。免疫共沉淀实验结果表明,促血管生成因子VEGF与血管抑制因子PEDF在小鼠视网膜组织中存在相互作用。免疫荧光染色结果显示,PEDF与VEGF在C57BL/6J与rdf小鼠的原代视网膜内皮细胞中均存在共定位。C57BL/6J常氧组原代视网膜内皮细胞VEGF/PEDF光密度比值为4.55±1.35,C57BL/6J高氧组为26.39±7.58,rdf常氧组为0.52±0.38,rdf高氧组为1.76±0.46,各组间比较差异均有统计学意义(均为P<0.05)。结论在视网膜色素变性rdf小鼠视网膜中,VEGF/PEDF平衡向抗血管生成方向显著偏移,小鼠视网膜促血管生成因子低表达与抗血管生成因子高表达共同抑制了氧诱导后病理性新生血管的形成。 展开更多
关键词 视网膜新生血管 氧诱导视网膜病变 血管内皮生长因子 色素上皮衍生因子 rdf小鼠
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Joint Optimization of Routing and Resource Allocation in Decentralized UAV Networks Based on DDQN and GNN
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作者 Nawaf Q.H.Othman YANG Qinghai JIANG Xinpei 《电讯技术》 北大核心 2026年第1期1-10,共10页
Optimizing routing and resource allocation in decentralized unmanned aerial vehicle(UAV)networks remains challenging due to interference and rapidly changing topologies.The authors introduce a novel framework combinin... Optimizing routing and resource allocation in decentralized unmanned aerial vehicle(UAV)networks remains challenging due to interference and rapidly changing topologies.The authors introduce a novel framework combining double deep Q-networks(DDQNs)and graph neural networks(GNNs)for joint routing and resource allocation.The framework uses GNNs to model the network topology and DDQNs to adaptively control routing and resource allocation,addressing interference and improving network performance.Simulation results show that the proposed approach outperforms traditional methods such as Closest-to-Destination(c2Dst),Max-SINR(mSINR),and Multi-Layer Perceptron(MLP)-based models,achieving approximately 23.5% improvement in throughput,50% increase in connection probability,and 17.6% reduction in number of hops,demonstrating its effectiveness in dynamic UAV networks. 展开更多
关键词 decentralized UAV network resource allocation routing algorithm GNN DDQN DRL
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Research on the Optimal Allocation of Community Elderly Care Service Resources Based on Big Data Technology
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作者 Shuying Li 《Journal of Clinical and Nursing Research》 2026年第1期241-246,共6页
With the accelerating aging process of China’s population,the demand for community elderly care services has shown diversified and personalized characteristics.However,problems such as insufficient total care service... With the accelerating aging process of China’s population,the demand for community elderly care services has shown diversified and personalized characteristics.However,problems such as insufficient total care service resources,uneven distribution,and prominent supply-demand contradictions have seriously affected service quality.Big data technology,with core advantages including data collection,analysis and mining,and accurate prediction,provides a new solution for the allocation of community elderly care service resources.This paper systematically studies the application value of big data technology in the allocation of community elderly care service resources from three aspects:resource allocation efficiency,service accuracy,and management intelligence.Combined with practical needs,it proposes optimal allocation strategies such as building a big data analysis platform and accurately grasping the elderly’s care needs,striving to provide operable path references for the construction of community elderly care service systems,promoting the early realization of the elderly care service goal of“adequate support and proper care for the elderly”,and boosting the high-quality development of China’s elderly care service industry. 展开更多
关键词 Big data technology COMMUNITY Elderly care Service resources
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Occurrence modes and comprehensive utilization of critical metal resources associated with coal:A review
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作者 Qin Zhang Wei Cheng +6 位作者 Tiebin Zhang Hongbo Liu Jiwei Yuan Aoao Chen Tingshun Wang Qian Liu Jianghe Wang 《International Journal of Mining Science and Technology》 2026年第2期277-293,共17页
Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a syste... Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a systematic review of the enrichment characteristics,occurrence modes,and comprehensive utilization potential of these critical metals in coal.Globally,the distribution of these metal resources exhibits significant regional heterogeneity.While the concentration in most coals falls below industrial cut-off grades,anomalous enrichment in specific coal basins results in Li,Ga,Ge,and REE concentrations far exceeding global averages,highlighting their considerable potential as unconventional metal deposits.The occurrence modes of these metals are diverse:Li is primarily hosted in mineral phases;Ga exists in inorganic,organic,and complex forms;Ge shows a strong association with organic matter;and REE are mainly present in adsorbed/isomorphic forms within clay minerals,while also displaying organic affinity.Direct extraction of metals from raw coal is often cost-prohibitive;effective recovery is therefore more feasible when integrated with coal processing.Metals are further enriched in solid wastes such as coal gangue,fly ash,and bottom ash,from which recovery is more economically and technically viable.Current comprehensive utilization primarily employs integrated mineral processing-hydrometallurgy approaches.Future research should focus on elucidating the precise occurrence forms of metals in coal and solid wastes,optimizing pre-treatment methods,and selecting effective activators and leachants.Advancing the synergistic extraction and green recovery of multiple associated resources from coal and its by-products is essential for achieving high-value,comprehensive utilization of coal-based resources. 展开更多
关键词 Coal-associated resources Lithium GALLIUM GERMANIUM Rare carth elements Extraction and separation
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Turning Black Waste into a Green Resource
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作者 LIU JING 《China Today》 2026年第1期68-70,共3页
To deal with a polluted by-product of coal production,central China’s Shanxi Province has explored a governance path that addresses both the symptoms and root causes.
关键词 black waste green resource polluted product shanxi province coal production governance path
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Water resources and sustainable management in Tajikistan under global change
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作者 CHEN Yaning FANG Gonghuan +5 位作者 LI Zhi ZHANG Xueqi LI Weihong Nekruz GULAHMADOV Farhod NASRULLOEV Aminjon GULAKHMADOV 《Regional Sustainability》 2026年第1期1-10,共10页
As a major source of freshwater in Central Asia,Tajikistan is endowed with abundant glaciers and water resources.However,the country faces multiple challenges,including accelerated glacier retreat,complex inter-govern... As a major source of freshwater in Central Asia,Tajikistan is endowed with abundant glaciers and water resources.However,the country faces multiple challenges,including accelerated glacier retreat,complex inter-government water resource management,and inefficient water use.Existing research has predominantly focused on individual hydrological processes,such as glacier retreat,snow cover change,or transboundary water issues,but it has yet to fully capture the overall complexity of water system.Tajikistan’s water system functions as an integrated whole from mountain runoff to downstream supply,but a comprehensive study of its water resource has yet to be conducted.To address this research gap,this study systematically examined the status,challenges,and sustainable management strategies of Tajikistan’s water resources based on a literature review,remote sensing data analysis,and case studies.Despite Tajikistan’s relative abundance of water resources,global warming is accelerating glacier melting and altering the hydrological cycles,which have resulted in unstable runoff patterns and heightened risks of extreme events.In Tajikistan,outdated infrastructure and poor management are primary causes of low water-use efficiency in the agricultural sector,which accounts for 85.00%of the total water withdrawals.At the governance level,Tajikistan faces challenges in balancing the water-energy-food nexus and transboundary water resource issues.To address these issues,this study proposes core paths for Tajikistan to achieve sustainable water resource management,such as accelerating technological innovation,promoting water-saving agricultural technologies,improving water resource utilization efficiency,and establishing a community participation-based comprehensive management framework.Additionally,strengthening cross-border cooperation and improving real-time monitoring systems have been identified as critical steps to advance sustainable water resource utilization and evidence-based decision-making in Tajikistan and across Central Asia. 展开更多
关键词 Climate change Glacial retreat Cross-border cooperation Water resource management TAJIKISTAN Central Asia
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AI and ML in groundwater exploration and water resources management:Concepts,methods,applications,and future directions
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作者 Adla Andalu MGopal Naik Sandeep Budde 《Journal of Groundwater Science and Engineering》 2026年第1期100-122,共23页
The integration of Artificial Intelligence(AI)and Machine Learning(ML)into groundwater exploration and water resources management has emerged as a transformative approach to addressing global water challenges.This rev... The integration of Artificial Intelligence(AI)and Machine Learning(ML)into groundwater exploration and water resources management has emerged as a transformative approach to addressing global water challenges.This review explores key AI and ML concepts,methodologies,and their applications in hydrology,focusing on groundwater potential mapping,water quality prediction,and groundwater level forecasting.It discusses various data acquisition techniques,including remote sensing,geospatial analysis,and geophysical surveys,alongside preprocessing methods that are essential for enhancing model accuracy.The study highlights AI-driven solutions in water distribution,allocation optimization,and realtime resource management.Despite their advantages,the application of AI and ML in water sciences faces several challenges,including data scarcity,model reliability,and the integration of these tools with traditional water management systems.Ethical and regulatory concerns also demand careful consideration.The paper also outlines future research directions,emphasizing the need for improved data collection,interpretable models,real-time monitoring capabilities,and interdisciplinary collaboration.By leveraging AI and ML advancements,the water sector can enhance decision-making,optimize resource distribution,and support the development of sustainable water management strategies. 展开更多
关键词 Artificial intelligence Machine learning Groundwater exploration Hydrological modeling Remote sensing applications Water resources management
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Intelligent Resource Allocation for Multiaccess Edge Computing in 5G Ultra-Dense Slicing Network Using Federated Multiagent DDPG Algorithm
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作者 Gong Yu Gong Pengwei +3 位作者 Jiang He Xie Wen Wang Chenxi Xu Peijun 《China Communications》 2026年第1期273-289,共17页
Nowadays,advances in communication technology and cloud computing have spawned a variety of smart mobile devices,which will generate a great amount of computing-intensive businesses,and require corresponding resources... Nowadays,advances in communication technology and cloud computing have spawned a variety of smart mobile devices,which will generate a great amount of computing-intensive businesses,and require corresponding resources of computation and communication.Multiaccess edge computing(MEC)can offload computing-intensive tasks to the nearby edge servers,which alleviates the pressure of devices.Ultra-dense network(UDN)can provide effective spectrum resources by deploying a large number of micro base stations.Furthermore,network slicing can support various applications in different communication scenarios.Therefore,this paper integrates the ultra-dense network slicing and the MEC technology,and introduces a hybrid computing offloading strategy in order to satisfy various quality of service(QoS)of edge devices.In order to dynamically allocate limited resources,the above problem is formulated as multiagent distributed deep reinforcement learning(DRL),which will achieve low overhead computation offloading strategy and real-time resource allocation decisions.In this context,federated learning is added to train DRL agents in a distributed manner,where each agent is dedicated to exploring actions composed of offloading decisions and allocating resources,so as to jointly optimize system delay and energy consumption.Simulation results show that the proposed learning algorithm has better performance compared with other strategies in literature. 展开更多
关键词 federated learning multiaccess edge computing mutiagent deep reinforcement learning resource allocation ultra-dense slicing network
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Optimal competitive resource assignment in two-stage Colonel Blotto game with Lanchester-type attrition
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作者 YUAN Weilin CHEN Shaofei +4 位作者 HU Zhenzhen JI Xiang LU Lina SU Xiaolong CHEN Jing 《Journal of Systems Engineering and Electronics》 2026年第1期242-256,共15页
In strategic decision-making tasks,determining how to assign limited costly resource towards the defender and the attacker is a central problem.However,it is hard for pre-allocated resource assignment to adapt to dyna... In strategic decision-making tasks,determining how to assign limited costly resource towards the defender and the attacker is a central problem.However,it is hard for pre-allocated resource assignment to adapt to dynamic fighting scenarios,and exists situations where the scenario and rule of the Colonel Blotto(CB)game are too restrictive in real world.To address these issues,a support stage is added as supplementary for pre-allocated results,in which a novel two-stage competitive resource assignment problem is formulated based on CB game and stochastic Lanchester equation(SLE).Further,the force attrition in these two stages is formulated as a stochastic progress to consider the complex fighting progress,including the case that the player with fewer resources defeats the player with more resources and wins the battlefield.For solving this two-stage resource assignment problem,nested solving and no-regret learning are proposed to search the optimal resource assignment strategies.Numerical experiments are taken to analyze the effectiveness of the proposed model and study the assignment strategies in various cases. 展开更多
关键词 resource assignment Colonel Blotto(CB)game stochastic Lanchester equation(SLE) regret match
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The pathway to discovering antiviral drugs from marine resources
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作者 Wei Wang 《Infectious Diseases Research》 2026年第1期1-3,共3页
Owing to the emergence of drug resistance and high morbidity,the need for novel antiviral drugs with novel targets is highly sought after.Marine-derived compounds mostly possess potent antiviral activity and serve as ... Owing to the emergence of drug resistance and high morbidity,the need for novel antiviral drugs with novel targets is highly sought after.Marine-derived compounds mostly possess potent antiviral activity and serve as a primary source for developing novel antiviral drugs,making the rapid discovery and evaluation of marine antiviral agents particularly crucial.Thus,future research should place greater emphasis on the identification of novel antiviral targets through the combination of artificial intelligence(AI)and structural pharmacology,as well as expanding the marine resource and target databases. 展开更多
关键词 identification novel antiviral targets discovery evaluation antiviral drugs artificial intelligence ai drug resistance developing novel antiviral drugsmaking marine resources marine antiviral agents
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Mineral resources of Asia continent:Resource endowment,mining industry pattern,and contributions to the world economy
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作者 Xi-feng Chen Gang Wang +2 位作者 Yan-xiong Mei Hai-jie Zhao Yan-yun Ma 《China Geology》 2026年第1期1-24,共24页
Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of mineral... Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation. 展开更多
关键词 Mineral resource endowment Minerogenetic series Metallogenic specialization Carbonate-type REE deposits Weathering-type REE deposits Hard rock-type lithium deposits Laterite nickel deposits Crystalline graphite deposits Magmatic nickel deposits Significant metallogenic belt Mining industry development pattern Mineral exploration and exploitation World economy Contribution Asia continent
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Overview of in-situ oxygen production technologies for lunar resources 被引量:2
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作者 Youpeng Xu Sheng Pang +5 位作者 Liangwei Cong Guoyu Qian Dong Wang Laishi Li Yusheng Wu Zhi Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期233-255,共23页
The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extract... The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic oxides.This oxygen and metal extraction can be achieved using existing metallurgical techniques.Furthermore,the ample reserves of water ice on the Moon offer another means for oxygen production.This paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental conditions.It delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar regolith.The two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the Moon.Considering the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the Moon.This review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives. 展开更多
关键词 lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis
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RDF技术在固体废物处理中的应用 被引量:1
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作者 金晶 王清森 +4 位作者 郑伟 王庆 冯旭 朱光鼒 王殿二 《绿色科技》 2025年第6期171-174,213,共5页
为探讨RDF技术在国内外固体废物处理中的应用现状,分析了制约其推广的关键因素,并提出了改进措施,以促进RDF技术的广泛应用,助力实现“双碳”目标。通过文献综述、案例分析等方法,详细阐述了RDF技术在生活垃圾、陈腐垃圾、一般工业固废... 为探讨RDF技术在国内外固体废物处理中的应用现状,分析了制约其推广的关键因素,并提出了改进措施,以促进RDF技术的广泛应用,助力实现“双碳”目标。通过文献综述、案例分析等方法,详细阐述了RDF技术在生活垃圾、陈腐垃圾、一般工业固废和园林废弃物处理中的应用进展,深入剖析了阻碍RDF技术推广的原因,包括标准体系不完善、制备成本高、缺乏投资补贴、环保排放问题以及经济效益不佳等。结果表明:国内RDF技术起步较晚,但近年来在生活垃圾、一般工业固废和园林废弃物处理方面取得了一定进展。 展开更多
关键词 rdf技术 固废处理 改进建议
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基于HINT的时态RDF语义索引和查询研究
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作者 张航 刘宇 《计算机与数字工程》 2025年第12期3477-3483,共7页
鉴于时态信息是知识图谱中的重要属性,研究人员已提出了多种高效存储和查询时态RDF的方案。然而,现有的时态RDF的存储和查询未能充分利用三元组之间的时态语义关系,从而会影响面向时态RDF的语义查询性能。针对上述问题,提出了基于区间索... 鉴于时态信息是知识图谱中的重要属性,研究人员已提出了多种高效存储和查询时态RDF的方案。然而,现有的时态RDF的存储和查询未能充分利用三元组之间的时态语义关系,从而会影响面向时态RDF的语义查询性能。针对上述问题,提出了基于区间索引HINT的时态RDF索引结构,该索引结构融合了HINT的层次索引和RDF的组合位图索引,从而使索引结构能蕴含三元组之间的时态语义关系。在HINT和组合位图索引的基础上,实现了面向SPARQL的时态算子,能够支持十三种Allen时态关系的语义查询。实验结果表明,基于HINT的时态RDF语义索引能够提升时态RDF的查询性能。 展开更多
关键词 知识图谱 时态rdf 两层索引 时态语义 查询优化
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面向双时态RDF星型查询的两阶段索引方法
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作者 王刚 张薇 +1 位作者 陈宏栉 张富 《东北大学学报(自然科学版)》 北大核心 2025年第2期18-27,共10页
为了对时间信息进行表示和处理,随之开展了时态RDF(temporal resource description framework)的扩展研究,而如何对时态RDF数据进行有效的管理也逐渐成为了一个重要问题.构建有效的索引机制是管理时态RDF数据和提高查询效率的重要途径之... 为了对时间信息进行表示和处理,随之开展了时态RDF(temporal resource description framework)的扩展研究,而如何对时态RDF数据进行有效的管理也逐渐成为了一个重要问题.构建有效的索引机制是管理时态RDF数据和提高查询效率的重要途径之一.本文提出了一种针对双时态RDF(bitemporal RDF)星型查询的两阶段索引方法:第一阶段索引提出一种基于双时态RDF节点邻域信息的候选集生成方法,第二阶段索引进一步提出一种基于位图索引的结果集生成方法.通过两阶段索引可以避免星型查询中成本昂贵的连接操作,快速得到查询结果.在查询效率和索引性能方面进行了对比实验,验证了所提方法的有效性. 展开更多
关键词 资源描述框架(rdf) 双时态rdf 星型查询 两阶段索引 位图索引
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Current status and diversity of fish resources in the Pinglu Canal Century Project 被引量:1
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作者 LU Jia TANG Wei +3 位作者 WANG Li XU Shengxian ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第4期131-144,共14页
[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of... [Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project. 展开更多
关键词 Pinglu Canal Project inter-basin connectivity fish resources community structure BIODIVERSITY influencing factors
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Non-Terrestrial Network Resource Management Towards 6G:Technology,Development,and Future Challenges 被引量:2
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作者 Xu Kexin Zhang Haijun +2 位作者 Du Bing Wang Lina Long Keping 《China Communications》 2025年第8期228-244,共17页
In the sixth generation mobile communication(6G) system,Non-Terrestrial Networks(NTN),as a supplement to terrestrial network,can meet the requirements of wide area intelligent connection and global ubiquitous seamless... In the sixth generation mobile communication(6G) system,Non-Terrestrial Networks(NTN),as a supplement to terrestrial network,can meet the requirements of wide area intelligent connection and global ubiquitous seamless access,establish intelligent connection for wide area objects,and provide intelligent services.Due to issues such as massive access,doppler shift,and limited spectrum resources in NTN,research on resource management is crucial for optimizing NTN performance.In this paper,a comprehensive survey of multi-pattern heterogeneous NTN resource management is provided.Firstly,the key technologies involved in NTN resource management is summarized.Secondly,NTN resource management is discussed from network pattern and resource pattern.The network pattern focuses on the application of different optimization methods to different network dimension communication resource management,and the resource type pattern focuses on the research and application of multi-domain resource management such as computation,cache,communication and sensing.Finally,future research directions and challenges of 6G NTN resource management are discussed. 展开更多
关键词 Non-terrestrial networks resource management 6G
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Computation and wireless resource management in 6G space-integrated-ground access networks 被引量:1
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作者 Ning Hui Qian Sun +2 位作者 Lin Tian Yuanyuan Wang Yiqing Zhou 《Digital Communications and Networks》 2025年第3期768-777,共10页
In 6th Generation Mobile Networks(6G),the Space-Integrated-Ground(SIG)Radio Access Network(RAN)promises seamless coverage and exceptionally high Quality of Service(QoS)for diverse services.However,achieving this neces... In 6th Generation Mobile Networks(6G),the Space-Integrated-Ground(SIG)Radio Access Network(RAN)promises seamless coverage and exceptionally high Quality of Service(QoS)for diverse services.However,achieving this necessitates effective management of computation and wireless resources tailored to the requirements of various services.The heterogeneity of computation resources and interference among shared wireless resources pose significant coordination and management challenges.To solve these problems,this work provides an overview of multi-dimensional resource management in 6G SIG RAN,including computation and wireless resource.Firstly it provides with a review of current investigations on computation and wireless resource management and an analysis of existing deficiencies and challenges.Then focusing on the provided challenges,the work proposes an MEC-based computation resource management scheme and a mixed numerology-based wireless resource management scheme.Furthermore,it outlines promising future technologies,including joint model-driven and data-driven resource management technology,and blockchain-based resource management technology within the 6G SIG network.The work also highlights remaining challenges,such as reducing communication costs associated with unstable ground-to-satellite links and overcoming barriers posed by spectrum isolation.Overall,this comprehensive approach aims to pave the way for efficient and effective resource management in future 6G networks. 展开更多
关键词 Space-integrated-ground Radio access network MEC-based computation resource management Mixed numerology-based wireless resource management
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Geological characteristics,resource potential,and development direction of shale gas in China 被引量:4
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作者 GUO Xusheng WANG Ruyue +3 位作者 SHEN Baojian WANG Guanping WAN Chengxiang WANG Qianru 《Petroleum Exploration and Development》 2025年第1期17-32,共16页
By reviewing the research progress and exploration practices of shale gas geology in China,analyzing and summarizing the geological characteristics,enrichment laws,and resource potential of different types of shale ga... By reviewing the research progress and exploration practices of shale gas geology in China,analyzing and summarizing the geological characteristics,enrichment laws,and resource potential of different types of shale gas,the following understandings have been obtained:(1)Marine,transitional,and lacustrine shales in China are distributed from old to new in geological age,and the complexity of tectonic reworking and hydrocarbon generation evolution processes gradually decreases.(2)The sedimentary environment controls the type of source-reservoir configuration,which is the basis of“hydrocarbon generation and reservoir formation”.The types of source-reservoir configuration in marine and lacustrine shales are mainly source-reservoir integration,with occasional source-reservoir separation.The configuration types of transitional shale are mainly source-reservoir integration and source-reservoir symbiosis.(3)The resistance of rigid minerals to compression for pore preservation and the overpressure facilitate the enrichment of source-reservoir integrated shale gas.Good source reservoir coupling and preservation conditions are crucial for the shale gas enrichment of source-reservoir symbiosis and source-reservoir separation types.(4)Marine shale remains the main battlefield for increasing shale gas reserves and production in China,while transitional and lacustrine shales are expected to become important replacement areas.It is recommended to carry out the shale gas exploration at three levels:Accelerate the exploration of Silurian,Cambrian,and Permian marine shales in the Upper-Middle Yangtze region;make key exploration breakthroughs in ultra-deep marine shales of the Upper-Middle Yangtze region,the new Ordovician marine shale strata in the North China region,the transitional shales of the Carboniferous and Permian,as well as the Mesozoic lacustrine shale gas in basins such as Sichuan,Ordos and Songliao;explore and prepare for new shale gas exploration areas such as South China and Northwest China,providing technology and resource reserves for the sustainable development of shale gas in China. 展开更多
关键词 shale gas marine shale transitional shale lacustrine shale source-reservoir configuration enrichment mechanism resource potential
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Do energy intensity,resource abundance and inequality drive energy poverty?Evidence from developing countries 被引量:2
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作者 Ashar Awan Mustafa Kocoglu +2 位作者 Mohammad Subhan Mohammed Shakib Nora Yusma bte Mohamed Yusoff 《Geoscience Frontiers》 2025年第3期119-136,共18页
Energy poverty in developing countries is a critical issue characterized by the lack of access to modern energy services,such as electricity and clean cooking facilities,as marked in SDG 7.This study explores the corr... Energy poverty in developing countries is a critical issue characterized by the lack of access to modern energy services,such as electricity and clean cooking facilities,as marked in SDG 7.This study explores the correlations between energy poverty,energy intensity,resource abundance,and income inequality,as these factors have been theorized to play important roles in influencing energy poverty in developing countries.By observing that the dataset is heterogeneous across the countries and over the time frame,we use the Method of Moments Quantile Regression(MMQR)to analyze our developing countries’data from 2000 to 2019.Our findings indicate that energy intensity is a significant factor influencing energy poverty,suggesting that higher energy consumption relative to the sample countries can exacerbate this issue.Additionally,we observe that income inequality within the sample countries is a critical determinant of energy poverty levels,highlighting the dynamics between economic disparity and access to energy resources.Interestingly,our study reveals that resource abundance acts as a blessing rather than a curse in terms of energy poverty,implying that countries rich in natural resources may have better opportunities to combat energy deprivation.Finally,we emphasize the vital role of financial markets in addressing energy poverty on a global scale,suggesting that robust financial systems can facilitate investments and innovations aimed at improving energy access for vulnerable populations.The results from the robustness analysis support the empirical results obtained from the main estimation.The empirical findings of the present study advance important comprehensions for policymakers to adopt energy policies that address the complex challenges of energy poverty and promote inclusive energy access. 展开更多
关键词 Energy poverty Natural resources Energy Intensity INEQUALITY Developing countries SDGs
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