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羊踯躅内生真菌Penicillium sp.RM的次生代谢产物及其肿瘤细胞增殖抑制活性研究
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作者 王雪 周磊 +3 位作者 胡倚航 刘洋 张雪 刘云宝 《中国中药杂志》 北大核心 2026年第2期444-449,共6页
对羊踯躅内生真菌Penicillium sp.RM的次级代谢产物进行研究,采用硅胶柱色谱、凝胶柱色谱、半制备液相色谱等进行分离纯化,共从Penicillium sp.RM发酵物的乙酸乙酯部位中分离鉴定出10个化合物,利用NMR、MS、UV、IR、CD等现代波谱技术确... 对羊踯躅内生真菌Penicillium sp.RM的次级代谢产物进行研究,采用硅胶柱色谱、凝胶柱色谱、半制备液相色谱等进行分离纯化,共从Penicillium sp.RM发酵物的乙酸乙酯部位中分离鉴定出10个化合物,利用NMR、MS、UV、IR、CD等现代波谱技术确定了化合物的结构,分别为penicidienone A(1)、diversonol(2)、alternariol(3)、alternariol 9-methyl ether(4)、methyla-ted dechloromonilicin(5)、norliquexantona(6)、alternethanoxin A(7)、α-diversonolic ester(8)、(±)-asperlone A(9)、verruculotoxin(10),其中化合物1是1种新的环戊烯酮衍生物。肿瘤细胞增殖抑制活性筛选结果表明化合物9对HepG2、HGC27、U251细胞具有抑制作用,IC50分别为9.7、9.3、8.4μmol·L-1。 展开更多
关键词 羊踯躅 内生真菌 Penicillium sp.rm 次生代谢产物 环戊烯酮
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Trends in alpha diversity,community composition,and network complexity of rare,intermediate,and abundant bacterial taxa along a latitudinal gradient and their impact on ecosystem multifunctionality 被引量:1
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作者 Rong Tang Shuaifeng Li +3 位作者 Xiaobo Huang Rui Zhang Cong Li Jianrong Su 《Forest Ecosystems》 2025年第4期642-654,共13页
Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions ... Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions affect EMF remain largely unknown.Here,we investigated variation in three measures of diversity(alpha diversity,community composition and network complexity)among rare,intermediate,and abundant taxa across a latitudinal gradient spanning five forest plots in Yunnan Province,China and examined their contributions on EMF.We aimed to characterize the diversity distributions of bacterial groups across latitudes and to assess the differences in the mechanisms underlying their contributions to EMF.We found that multifaceted diversity(i.e.,diversity assessed by the three different metrics)of rare,intermediate,and abundant bacteria generally decreased with increasing latitude.More importantly,we found that rare bacterial taxa tended to be more diverse,but they contributed less to EMF than intermediate or abundant bacteria.Among the three dimensions of diversity we assessed,only community composition significantly affected EMF across all locations,while alpha diversity had a negative effect,and network complexity showed no significant impact.Our study further emphasizes the importance of intermediate and abundant bacterial taxa as well as community composition to EMF and provides a theoretical basis for investigating the mechanisms by which belowground microorganisms drive EMF along a latitudinal gradient. 展开更多
关键词 BACTERIA Ecosystem multifunctionality Alpha diversity Community composition Network complexity Latitudinal gradient
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High performance multifunction integrated optic circuits base on thin-film lithium niobate
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作者 QU Bai-Ang GUO Hong-Jie +4 位作者 YANG Yong-Kang CHEN Wen-Bin ZHANG Xue-Chen GUO Wen-Tao TAN Man-Qing 《红外与毫米波学报》 北大核心 2026年第1期30-35,共6页
This paper introduces an innovative Multifunction Integrated Optic Circuit(MIOC)design utilizing thin-film lithium niobate,surpassing traditional bulk waveguide-based MIOCs in terms of size,half-wave voltage requireme... This paper introduces an innovative Multifunction Integrated Optic Circuit(MIOC)design utilizing thin-film lithium niobate,surpassing traditional bulk waveguide-based MIOCs in terms of size,half-wave voltage requirements,and integration capabilities.By implementing a sub-wavelength grating structure,we achieve a Po⁃larization Extinction Ratio(PER)exceeding 29 dB.Furthermore,our electrode design facilitates a voltage-length product(V_(π)L)below 2 V·cm,while a double-tapered coupling structure significantly reduces insertion loss.This advancement provides a pivotal direction for the miniaturization and integration of optical gyroscopes,marking a substantial contribution to the field. 展开更多
关键词 multifunction integrated optic circui(t MIOC) thin-film lithium niobate sub-wavelength grating polarization extinction ratio
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TETRA数字集群系统中截短RM码的改进译码方法
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作者 李鑫 孙敬伟 《电子技术应用》 2026年第2期52-56,共5页
对TETRA(Terrestrial Trunked Radio)数字集群系统中使用的截短RM(Reed-Muller)码进行研究,提出了基于大数逻辑译码算法的改进方法。首先,对接收到的30位软比特信息码元按幅值的绝对值由大到小排序,依次反转序列后几位可靠度较低码元的... 对TETRA(Terrestrial Trunked Radio)数字集群系统中使用的截短RM(Reed-Muller)码进行研究,提出了基于大数逻辑译码算法的改进方法。首先,对接收到的30位软比特信息码元按幅值的绝对值由大到小排序,依次反转序列后几位可靠度较低码元的符号位得到多个新的序列,再对新序列进行大数逻辑译码。最后计算新序列译码结果的代价函数,选择代价函数最小的作为最终译码结果。该方法改善了接收数据中低可靠度码元对译码结果的影响,提升了译码性能。所提出的方法可接近最大似然译码效果,在信噪比较低的情况下依然具有较好的译码性能。 展开更多
关键词 TETRA 截短rm 大数逻辑译码算法 代价函数
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Hydro-saline synergy regulates ecosystem multifunctionality via microbial biomass in semi-arid grasslands,China
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作者 HU Jinpeng HE Yuanyuan +2 位作者 LI Yuanhong ZHANG Yuewei ZHANG Jinlin 《Journal of Arid Land》 2026年第3期524-546,共23页
Soil water content and salinity critically regulate soil microbial composition,plant community structure,and ecosystem multifunctionality(EMF)in semi-arid grasslands.However,the mechanisms through which drought(D),sal... Soil water content and salinity critically regulate soil microbial composition,plant community structure,and ecosystem multifunctionality(EMF)in semi-arid grasslands.However,the mechanisms through which drought(D),saline-alkaline(SA),and their combined(DSA)stress influence these ecological components remain poorly understood.This study investigated these mechanisms along natural gradients in a semi-arid grassland of China by analyzing soil physical-chemical properties,microbial communities,and vegetation characteristics.The results showed that as the environmental stress shifted from the D group to the DSA group and then to the SA group,soil electrical conductivity significantly increased,while urease and phosphatase activities significantly decreased.Soil organic carbon,total nitrogen,total phosphorus,and microbial biomass carbon and nitrogen were lower in the D and SA groups than in the DSA group.Meanwhile,plant biomass showed an increasing trend along the treatment gradient,primarily driven by dominant species,while plant diversity did not exhibit significant differences.Further analysis identified the soil water content and salinity as the key determinants of soil microbial diversity and community complexity.Soil enzyme activities exhibited contrasting relationships with microbial composition,correlating positively with the richness of bacterial amplicon sequence variants(ASVs)but negatively with the richness of fungal ASVs.Notably,microbial biomass,which varied significantly across different groups,emerged as a key predictor of changes in EMF,with its critical role confirmed through structural equation modeling.These findings collectively elucidate the responses of ecological communities to synergistic soil hydro-saline stress in semi-arid ecosystems,while highlighting the critical role of microbial biomass in maintaining EMF. 展开更多
关键词 hydro-saline soil microbial enzyme activity ecosystem multifunctionality semi-arid grassland
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Restoration boosts soil P-cycle multifunctionality in karst ecosystems by modulating soil properties and rare bacterial taxa
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作者 Fujing Pan Xuan Yu +4 位作者 Yueming Liang Peilei Hu Kelin Wang Wei Zhang Qian Yang 《Journal of Integrative Agriculture》 2026年第2期513-528,共16页
Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient ... Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient balance within ecosystems,and enhancing ecosystem adaptability and resilience.This cycle is influenced by factors such as the restoration approach and microbial community dynamics.However,the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood.The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function,and it provides insights into changes in the P cycle between different restoration approaches.To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches,we analyzed soil available P (AP),total P (TP),microbial biomass P (MBP),and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP).These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches(artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland,CP) at six subtropical karst ecosystem sites in China.We also determined the soil organic carbon (SOC),exchangeable calcium (Ca) and magnesium (Mg),pH,bulk density (BD),microbial biomass C (MBC),and microbial biomass nitrogen (MBN),as well as the community structure,relative abundance,diversity indices,and co-occurrence networks of phoD-harboring bacteria.The results showed that the community structure of phoD-harboring bacteria varied significantly among AF,NF,and CP and across different temperature gradients.These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF,along with the ACP and ALP activities,but not the TP and AP contents.The P-cycle MFI values were significantly higher in NF compared to AF and CP,and the variation was significantly explained by restoration approach,temperature,MBC,MBN,SOC,exchangeable Ca,BD,community structure of phoD-harboring bacteria,and exchangeable Mg.Furthermore,natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC,microbial biomass,the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure,and ACP and ALP activities,but it reduced soil BD.The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera.This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems,with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity. 展开更多
关键词 karst ecosystem RESTORATION community phoD-harboring bacteria P-cycle multifunctionality rare taxa
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Impacts of small herbivore disturbance on grassland ecosystem multifunctionality on the Qinghai-Tibetan Plateau
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作者 TAN Zhaoxian YAO Baohui +6 位作者 WANG Rong WANG Yihong FAN Bo ZHANG Yan CHEN Xinyan FENG Jianzhuo QU Jiapeng 《Journal of Mountain Science》 2026年第3期1147-1164,共18页
As a critical global ecosystem,grasslands rely on complex aboveground-belowground interactions that underpin multifunctionality,yet their mechanisms remain poorly understood.Our investigation employed the plateau pika... As a critical global ecosystem,grasslands rely on complex aboveground-belowground interactions that underpin multifunctionality,yet their mechanisms remain poorly understood.Our investigation employed the plateau pika(Ochotona curzoniae),a small herbivore widely distributed throughout the Qinghai-Tibetan Plateau,as a model organism to examine the consequences of disturbance on plant diversity,soil properties,microbial diversity,and multifunctionality of grassland ecosystems.We found that high pika burrow density significantly reduced plant diversity(Shannon-Wiener and Chao1 indices)and aboveground biomass.It also increased soil pH and reduced ammonium nitrogen content.The soil microbial diversity,encompassing both bacteria and fungi,was markedly decreased in areas characterized by a high concentration of burrows.Microbial interaction networks demonstrated greater complexity in areas with high burrow densities,as revealed by the network analysis.Conversely,in regions characterized by low burrow density,a significant negative correlation was observed between the intricacy of soil bacterial networks and the multifunctionality of grassland ecosystems.Structural equation modelling showed that pika disturbance indirectly affected multifunctionality via changes in plant biomass and soil properties-notably,nitrate nitrogen explained 40%of multifunctionality variation under high disturbance.This investigation advances our understanding of complex aboveground-belowground linkages in grassland ecosystems,revealing novel mechanisms through which biodiversity governs ecosystem multifunctionality.Our findings underscore the critical role of small herbivores in shaping grassland ecosystem functions and emphasize the importance of maintaining balanced disturbance regimes to sustain ecosystem multifunctionality.This has immediate implications for global conservation policies on the Qinghai-Tibetan Plateau and analogous ecosystems. 展开更多
关键词 Plateau pika Plant diversity Soil microbes Ecosystem multifunctionality Qinghai-Tibetan Plateau
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Richness and biomass enhance soil multifunctionality in artificial shrub and grass restoration on alpine sandy landscapes of the Qinghai-Tibetan Plateau
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作者 anxin Wang Lixue Yang +4 位作者 Youjun Chen Qingping Zhou Yihe Lü Xuewei Shi Jian Hu 《Ecological Frontiers》 2026年第1期306-316,共11页
Several ecological restoration projects have been carried out to prevent and restore alpine sandy land,mainly by reestablishing vegetation through planting woody plants and grasses.However,our understanding of how shr... Several ecological restoration projects have been carried out to prevent and restore alpine sandy land,mainly by reestablishing vegetation through planting woody plants and grasses.However,our understanding of how shrub and grass restoration measures affect soil multifunctionality(SMF)in alpine and semi-humid areas remains limited.This study examined the effects of three typical restoration methods—artificial grass plus shrub planting(AGS),artificial grass planting(AG),and artificial shrub planting(AS)-on plant-soil functions and soil multifunctionality,as well as the factors influencing SMF compared to natural grassland(NG).The results showed that vegetation restoration improved aboveground plant characteristics and soil nutrients.Species richness(R),herbaceous plant coverage(Cover),and aboveground biomass(AGB)were higher in AGS than in AS.Soil organic carbon,nitrogen,and phosphorus levels decreased across AGS,AG,and AS,respectively.Additionally,vegetation restoration on sandy land significantly increased soil multifunctionality,with the SMF of AGS reaching 83.92%of that in NG.The structural equation model indicated that plant communities with higher species richness could enhance soil multifunctionality by increasing plant productivity.Compared to NG,soil bulk density negatively affected SMF directly,while soil water content(SWC)directly influenced R and AGB,and indirectly improved SMF through artificial shrub and grass vegetation restoration.Therefore,AGS enhanced SMF more than both AG and AS,and may be a more effective strategy for restoring soil functions in alpine and semi-humid sandy lands.Our findings suggest that combining grasses and shrubs in vegetation restoration offers a more sustainable approach,helping to combat desertification and improve management strategies in the alpine sub-humid region. 展开更多
关键词 DESERTIFICATION Qinghai-Tibetan Plateau Alpine grassland Sandy land Ecological restoration Soil multifunctionality
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Coplanar Floating-Gate Antiferroelectric Transistor with Multifunctionality for All-in-One Analog Reservoir Computing
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作者 Yufei Shi Zijie Zheng +5 位作者 Jiali Huo Yu‑Chieh Chien Sifan Li Haofei Zheng Xiao Gong Kah‑Wee Ang 《Nano-Micro Letters》 2026年第6期640-655,共16页
Analog reservoir computing(ARC)systems offer an energy-efficient platform for temporal information processing.However,their physical implementation typically requires disparate materials and device architectures for d... Analog reservoir computing(ARC)systems offer an energy-efficient platform for temporal information processing.However,their physical implementation typically requires disparate materials and device architectures for different system components,leading to complicated fabrication processes and increased system complexity.In this work,we present a coplanar floating-gate antiferroelectric field-effect transistor(FG AFeFET)that unifies multiple neural functionalities within a single device,enabling the physical implementation of a complete ARC system.By combining a coplanar layout design with an area ratio engineering strategy,we achieve tunable device behaviors,including volatile responses for artificial neuron emulation,nonvolatile states for synaptic functions,and fading memory dynamics for reservoir operations.The mechanisms underlying these functionalities and their operating mechanism are systematically elucidated using load line analysis and energy band diagrams.Leveraging these insights,we demonstrate an all-in-one ARC system based on the unified coplanar FG AFeFET architecture,which achieves recognition accuracies of 95.6%and 83.4%on the MNIST and Fashion-MNIST datasets,respectively.These findings highlight the potential of coplanar FG AFeFETs to deliver area-efficient,design-flexible neuromorphic hardware for next-generation computing systems. 展开更多
关键词 Hafnium zirconium oxide Coplanar structure Antiferroelectric field-effect transistor Reservoir computing multifunctionality
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Quantifying and predicting trait combinations to enhance ecological multifunctionality of urban broad-leaf forest tree species:leaf carbon content is an essential trait
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作者 Ruiting Wang Sheng Xu +3 位作者 Kexin Gao Yixin Zhang Yan Li Xingyuan He 《Journal of Forestry Research》 2026年第1期98-110,共13页
Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify... Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify TSEMF in response to environmental changes.However,there has been limited exploration of multitrait combinations for predicting TS-EMF across seasons and of trait thresholds that enhance TS-EMF.Here,for 10 dominant tree species in urban forests of Northeast China,14 traits were measured and four aboveground and three belowground ecological functions assessed in three seasons.Ecological functions and TS-EMF differed significantly throughout the seasons(P<0.05).Synergistic relationships were found between carbon sequestration and oxygen release,between cooling and humidification,and between organic carbon accumulation and nutrient cycling.Notably,aboveground multifunctionality played a leading role in TS-EMF.With seasonal changes,resource allocation shifted toward traits related to resource acquisition rather than conservation to maintain TS-EMF.The combination of traits that predicted TS-EMF varied by type,accounting for up to 66.45%of the variation.TS-EMF was primarily driven by leaf structure in spring and by nutrient accumulation in autumn.Leaf carbon content(LCC)consistently served as a stabilizing factor for predicting TS-EMF across seasons.At 36.5-36.8 mg g^(-1),LCC had its optimal effect on TS-EMF.Other traits in combination that positively influence total TS-EMF include leaf nitrogen content(3.43-3.45 mg g^(-1)),leaf phosphorus content(0.80-0.83 mg g^(-1)),and leaf area(65.86-68.43 cm^(2)).Within these specified trait thresholds,Morus alba and Quercus mongolica were identified as key species.These findings suggest that the trade-off between various ecological functions can be managed by altering plant traits across seasons.This approach could provide a theoretical foundation for enhancing the TS-EMF of urban forests through trait-based management,offering practical guidance for selecting tree species. 展开更多
关键词 Ecological multifunctionality of tree species Traits combination Urban forests Leaf carbon content
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Coordination Thermodynamic Control of Magnetic Domain Configuration Evolution toward Low‑Frequency Electromagnetic Attenuation
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作者 Tong Huang Dan Wang +9 位作者 Xue He Zhaobo Feng Zhiqiang Xiong Yuqi Luo Yuhui Peng Guangsheng Luo Xuliang Nie Mingyue Yuan Chongbo Liu Renchao Che 《Nano-Micro Letters》 2026年第3期860-875,共16页
The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)at... The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)attenuation behavior remain poorly understood.To address this gap,a thermodynamically controlled periodic coordination strategy is proposed to achieve precise modulation of magnetic nanoparticle spacing.This approach unveils the evolution of magnetic domain configurations,progressing from individual to coupled and ultimately to crosslinked domain configurations.A unique magnetic coupling phenomenon surpasses the Snoek limit in low-frequency range,which is observed through micromagnetic simulation.The crosslinked magnetic configuration achieves effective low-frequency EM wave absorption at 3.68 GHz,encompassing nearly the entire C-band.This exceptional magnetic interaction significantly enhances radar camouflage and thermal insulation properties.Additionally,a robust gradient metamaterial design extends coverage across the full band(2–40 GHz),effectively mitigating the impact of EM pollution on human health and environment.This comprehensive study elucidates the evolution mechanisms of magnetic domain configurations,addresses gaps in dynamic magnetic modulation,and provides novel insights for the development of high-performance,low-frequency EM wave absorption materials. 展开更多
关键词 Thermodynamically controlled coordination strategy Magnetic domain configuration Low-frequency electromagnetic wave absorption Electrical/magnetic coupling MULTIFUNCTION
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OSI-RM视角下的移动通信网络AI技术应用综述
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作者 章坚武 张天恒 +3 位作者 章谦骅 郭春生 傅剑峰 詹明 《电信科学》 北大核心 2025年第6期1-28,共28页
人工智能(artificial intelligence,AI)凭借其强大的推理、学习及自我修正能力,已成为解决复杂问题的重要技术,并广泛应用于尖端科技领域。移动通信网络作为现代信息社会的核心基础设施,其复杂性对网络构建、管理和优化提出了更高要求... 人工智能(artificial intelligence,AI)凭借其强大的推理、学习及自我修正能力,已成为解决复杂问题的重要技术,并广泛应用于尖端科技领域。移动通信网络作为现代信息社会的核心基础设施,其复杂性对网络构建、管理和优化提出了更高要求。开放系统互连参考模型(open systems interconnection reference model,OSI-RM)通过分层结构实现网络功能的模块化和标准化,为移动通信网络的设计与实现提供了重要理论框架,并指导多协议、多设备的互联互通。首先从OSI-RM的视角,系统梳理了AI技术在移动通信网络各层中的应用现状,分析了AI在解决移动通信网络复杂问题中的作用。同时,指出部分AI技术具备跨层应用的潜力,突破了单一层次的限制,为AI技术在移动通信网络中的深入研究与应用提供了新的方向。 展开更多
关键词 人工智能 开放系统互连参考模型 移动通信
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扰动激波与颗粒群的RM不稳定性研究
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作者 李林飞 金台 +2 位作者 邹立勇 罗坤 樊建人 《工程热物理学报》 北大核心 2025年第1期158-163,共6页
针对平面激波绕过圆柱产生的扰动激波与N2/SF6轻重气体界面相互作用产生的Richtmyer-Meshkov不稳定问题进行了数值模拟,研究了SF6中不同大小颗粒对不稳定发展的影响规律。计算结果表明,对于5µm、20µm、50µm三种不同尺寸... 针对平面激波绕过圆柱产生的扰动激波与N2/SF6轻重气体界面相互作用产生的Richtmyer-Meshkov不稳定问题进行了数值模拟,研究了SF6中不同大小颗粒对不稳定发展的影响规律。计算结果表明,对于5µm、20µm、50µm三种不同尺寸的颗粒,反射激波与轻重气体界面作用的时间和位置不同,50µm的颗粒中界面演化更充分,后期湍流化程度更高;比较反射激波与界面作用形成的涡旋结构的发展演化,SF6气体中会形成较多的尖钉、气泡结构,尖钉“腿部”由于剪切形成KH不稳定涡旋,最终形成大小不等的涡旋结构,转捩为湍流;5µm的小颗粒由于惯性小,跟随流体的运动能力更强,后期颗粒群演化出尖钉气泡结构,50µm的颗粒惯性大,与流体运动差别大,颗粒空间分布与气体界面不稳定发展有较大不同。 展开更多
关键词 扰动激波 rm不稳定 密度界面 颗粒 数值模拟
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面向实战的装备系统RMS综合仿真验证技术
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作者 张悦 张文良 +3 位作者 冯强 郭星 任羿 王自力 《系统仿真学报》 北大核心 2025年第7期1823-1835,共13页
针对现有装备系统的可靠性、维修性和保障性(reliability maintainability supportability,RMS)仿真验证通常基于典型条件开展,存在实战环境和任务建模能力弱的问题,提出了一种基于多智能体的RMS仿真验证框架。突破了复杂环境与多变任... 针对现有装备系统的可靠性、维修性和保障性(reliability maintainability supportability,RMS)仿真验证通常基于典型条件开展,存在实战环境和任务建模能力弱的问题,提出了一种基于多智能体的RMS仿真验证框架。突破了复杂环境与多变任务的智能体建模技术,构建了环境类智能体、任务类智能体与装备及保障系统的交互机制,给出了基于仿真的RMS综合评价方法。案例验证表明:所提出的RMS综合仿真验证方法能够实现复杂环境与多变任务建模,支持完成面向实战的仿真验证与设计方案综合评价,满足实战化研制需求。 展开更多
关键词 rmS(reliability maintainability supportability) 多智能体 仿真验证 复杂环境 多变任务
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基于RM-YOLOv8的热轧带钢表面缺陷检测 被引量:2
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作者 杨澳 侯红玲 +2 位作者 朱康凯 李相垚 赵妍棣 《锻压技术》 北大核心 2025年第2期103-114,共12页
针对传统热轧带钢表面缺陷检测算法在复杂工业环境下检测精度低、易漏检和误检等问题,提出一种基于RM-YOLOv8的热轧带钢表面缺陷检测算法。在特征提取网络中引入ConvNeXt Block模块,增强了网络特征提取能力;构建了注意力机制RC_MHSA,加... 针对传统热轧带钢表面缺陷检测算法在复杂工业环境下检测精度低、易漏检和误检等问题,提出一种基于RM-YOLOv8的热轧带钢表面缺陷检测算法。在特征提取网络中引入ConvNeXt Block模块,增强了网络特征提取能力;构建了注意力机制RC_MHSA,加强了特征提取网络对于特征图中感兴趣区域的训练;构建了轻量可学习视觉中心模块LLVC,并以跨层通道融合的方式向深层网络中加入更加丰富的特征信息,提高了模型对于局部角落特征的捕捉;最后,利用GhostBottleneck模块构造了一种轻量化模块C2f_Ghost,在减少计算量的同时,提高了网络的检测精度。实验结果表明,RM-YOLOv8在热轧带钢表面缺陷数据集NEU-DET上实验的平均精度均值相比于原始YOLOv8网络提升了7.0%,精确率提高了8.9%,召回率提高了6.8%。与其他检测算法相比,提出的RM-YOLOv8缺陷检测算法具有更好的检测性能和工业应用价值。 展开更多
关键词 热轧带钢 缺陷检测 深度学习 rm-YOLOv8 特征金字塔 注意力机制
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面向6G的RM码编译码方案 被引量:1
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作者 陈芳 陈景灿 +2 位作者 秦海生 魏岳军 李莉萍 《移动通信》 2025年第2期51-57,共7页
纠错编码是提升信道可靠性的重要途径。里德-穆勒(Reed-Muller)码作为最古老和最流行的码之一,其独特的码字结构使得编码和译码都具有较低的复杂度,并且可为其他码型的研究提供参考。2017年,RM码被证明可以在二进制擦除信道上实现信道容... 纠错编码是提升信道可靠性的重要途径。里德-穆勒(Reed-Muller)码作为最古老和最流行的码之一,其独特的码字结构使得编码和译码都具有较低的复杂度,并且可为其他码型的研究提供参考。2017年,RM码被证明可以在二进制擦除信道上实现信道容量,使得RM码的理论与应用再次引起关注。对RM码的编码结构和现有的译码算法进行论述与总结,并对当前译码算法的改进和发展进行综合论述。最后,对RM码作为6G的候选编码方案,未来需要开展的研究方向进行展望。 展开更多
关键词 rm rm码编码 递归列表译码 递归投影聚合译码 删余
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异常球菌RM菌株脂肪酶基因LIP的克隆、表达及酶学性质
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作者 郑炜彬 胡秋怡 +3 位作者 杨李 谭梓瀚 张玉璇 柯野 《福建农林大学学报(自然科学版)》 北大核心 2025年第4期533-543,共11页
【目的】探究异常球菌RM菌株高表达的脂肪酶基因(LIP)异源表达及其重组脂肪酶(rLIP)的酶学性质,为产脂肪酶微生物菌株的筛选提供新的来源参考,以及为低温脂肪酶的开发应用提供一定的理论依据。【方法】对异常球菌RM菌株的基因组及转录... 【目的】探究异常球菌RM菌株高表达的脂肪酶基因(LIP)异源表达及其重组脂肪酶(rLIP)的酶学性质,为产脂肪酶微生物菌株的筛选提供新的来源参考,以及为低温脂肪酶的开发应用提供一定的理论依据。【方法】对异常球菌RM菌株的基因组及转录组进行测序分析,筛选出表达量高的脂肪酶基因,重组至毕赤酵母GS115菌株中进行诱导表达;对rLIP的氨基酸残基序列和3-D结构进行分析,并探究其酶学性质。【结果】RM菌株表达了6个脂肪酶基因,其中只有1个基因编码胞外脂肪酶。序列比对分析表明,LIP与脂肪酶(国际蛋白结构数据库编号:5ah0.1.A)的序列一致性最高,为43.84%。LIP具有低温脂肪酶的催化三联体(Ser-Asp-His)和α/β水解酶折叠的典型结构特征。LIP基因在毕赤酵母GS115菌株中成功获得了表达。rLIP的最适底物为对硝基苯月桂酸酯和对硝基苯棕榈酸酯;rLIP最适反应温度为30℃,低于30℃有较高催化活性和稳定性;rLIP最适pH为8.0,pH为7.0~9.0时能保持50%以上的酶活性;Mg^(2+)对rLIP活性的提高有一定的促进作用。【结论】异常球菌RM菌株分泌的LIP是一种低温碱性脂肪酶,具有较强的稳定性和底物特异性。 展开更多
关键词 脂肪酶基因LIP 异常球菌rm菌株 蛋白结构预测 克隆表达 酶学性质
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典型炮射导弹性能与RMS设计仿真试验研究
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作者 李焕 邢文涛 +3 位作者 杜胜杰 郭成 魏艳娟 吴超云 《兵器装备工程学报》 北大核心 2025年第S2期151-158,184,共9页
通过对APS05型125毫米炮射导弹性能和RMS同步分析与设计,研发出满足作战需求的高可靠性炮射导弹。建立了炮射导弹性能和RMS综合权衡模型及设计分析平台,提高炮射导弹设计水平;编制炮射导弹性能和RMS综合权衡与设计分析技术应用指南,可... 通过对APS05型125毫米炮射导弹性能和RMS同步分析与设计,研发出满足作战需求的高可靠性炮射导弹。建立了炮射导弹性能和RMS综合权衡模型及设计分析平台,提高炮射导弹设计水平;编制炮射导弹性能和RMS综合权衡与设计分析技术应用指南,可为新型炮射导弹研制生产提供技术指导。 展开更多
关键词 炮射导弹 rmS设计 半实物仿真 仿真模型 装备
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Swift BAT硬X射线的RMS-Flux关系及流量分布研究
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作者 王亮 易庭丰 +1 位作者 王娜 张顺 《玉溪师范学院学报》 2025年第3期49-55,共7页
聚焦于Neil Gehrels Swift天文台的爆发警报望远镜(BAT)所发布的157个月硬X射线数据,深入探究了赛弗特活动星系核(SeyfertⅠ型和SeyfertⅡ型)、相对论性喷流活动星系核(Beamed AGN,包括Blazar和FSRQs)以及未定类型活动星系核(Unknown A... 聚焦于Neil Gehrels Swift天文台的爆发警报望远镜(BAT)所发布的157个月硬X射线数据,深入探究了赛弗特活动星系核(SeyfertⅠ型和SeyfertⅡ型)、相对论性喷流活动星系核(Beamed AGN,包括Blazar和FSRQs)以及未定类型活动星系核(Unknown AGN)的RMS-Flux的线性关系及其分布特征.研究过程中,首先对这4类活动星系核(AGNs)的硬X射线光变曲线进行分段处理,进而对RMS-Flux进行线性拟合.结果表明,各类AGNs均存在着较好的RMS-Flux线性关系.其中,Beamed AGN和SeyfertⅡ型的线性关系最为显著,SeyfertⅠ型次之,Unknown AGN相对较弱.研究推测,这一差异源于不同的辐射过程与机制,例如喷流、尘埃环以及吸积盘的冕,它们对硬X射线的调制程度各不相同.此外,针对4类AGNs光变曲线数据的流量分布,采用高斯函数和对数正态函数进行拟合,并开展Kolmogorov-Smirnov检验(K-S检验)、正态性检验(norm检验)以及卡方检验(Chi-Square检验).统计拟合结果显示:其流量分布更符合正态分布,这可能是由于BAT观测误差增强了流量分布的正态性. 展开更多
关键词 rmS-Flux 活动星系核 Swift BAT 硬X射线
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树种多样性对森林生态系统多功能性和韧性的影响 被引量:1
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作者 刘世荣 陈远其 +2 位作者 聂秀青 明安刚 王晖 《林业科学》 北大核心 2026年第1期1-18,共18页
生物多样性对森林生态系统功能和生态系统服务具有十分重要的影响,而不断加剧的气候变化正在严重威胁森林生物多样性及生态系统的健康和稳定性。为应对气候变化和保护生物多样性,提高森林生态系统韧性、多功能性和可持续性尤为重要。树... 生物多样性对森林生态系统功能和生态系统服务具有十分重要的影响,而不断加剧的气候变化正在严重威胁森林生物多样性及生态系统的健康和稳定性。为应对气候变化和保护生物多样性,提高森林生态系统韧性、多功能性和可持续性尤为重要。树种多样性是森林经营过程中关注的核心问题,直接影响森林生态系统的多功能性、稳定性和可持续性,是当今国内外森林生态学研究的前沿和热点。由于森林生态系统的复杂性(如类型多样、结构复杂以及对干扰和环境变化的时空动态响应),人们对树种多样性调控森林生态系统多功能性内在机理的认识还十分有限。本研究系统总结树种多样性对生态系统多功能性影响的生态学原理,包括生态位分化、资源分配与功能性状整合及拮抗、互补效应与选择效应、杠杆效应与功能冗余等;综述近年来树种多样性与生态系统多功能性的研究进展,涉及树种多样性对树木生长、林分生产力、根系及根系分泌物、土壤有机碳、土壤养分、土壤微生物和根系-土壤-微生物互作等生态过程与相关功能的影响,以及树种多样性对森林生态系统响应极端干旱、病虫害、外来物种入侵等的影响;结合经营实践,从树种选择与遗传多样性、混交与不同功能型树种组配、轮伐期调整与地力维持、景观配置与多功能性等方面提出人工林质量与生态系统多功能性协同提升的经营技术对策。最后,展望树种多样性与生态系统多功能性的未来研究趋势,探究应对气候变化与生物多样性保护相协同的近自然解决方案,以期为全球气候变化背景下森林生态系统经营,尤其是人工林多功能可持续经营提供科学依据和实践参考。 展开更多
关键词 森林 树种多样性 多功能性 韧性 功能性状 森林质量 人工林 气候变化
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