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Standardization Approach for Integration of Informatization and Industrialization Interview with Li Jun Informatization Research and Promotion Center ETIRI, MIIT
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作者 li jun 《China Standardization》 2017年第5期14-19,共6页
The fasting evolving information technology has driven the global industry into a new period of development where integration of informatization and industrialization became the focus of all countries around the world... The fasting evolving information technology has driven the global industry into a new period of development where integration of informatization and industrialization became the focus of all countries around the world,and a key trend for thousands of enterprises to follow.This now plays a decisive role on the evolution of world’s industrial development as well as the international competition. 展开更多
关键词 JUN LI
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Analysis and Countermeasures of a Lightning Accident Suffered by Hangjun 12 被引量:2
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作者 Jia Pei li jun +1 位作者 Zhu Fanglin Qi Jiuhan 《Meteorological and Environmental Research》 CAS 2014年第7期24-28,共5页
In the evening of October 17, 2012, the vessel Hangjun 12 of Changhang Wuhan Engineering Bureau was struck by lightning when working in Malaysia red ridge channel. In the lightning accident, the weather instrument of ... In the evening of October 17, 2012, the vessel Hangjun 12 of Changhang Wuhan Engineering Bureau was struck by lightning when working in Malaysia red ridge channel. In the lightning accident, the weather instrument of the ship was destroyed by the lightning to the ground, and the electronic information equipment in the vessel was influenced by induction lightning, which had damaged the electronic information system and elec- trical equipment. According to the Code for Design Protection of Structures against Lightning ( GB 50057-2010), this lightning accident suffered by Hangjun 12 was analyzed theoretically from aspects of the protection scope of the two lightning reds, main measures against lightning electromag- netic impulse, and specific reasons for the lightning accident. Finally, some measures to prevent the ship from being struck by lightning were put forward, such as improving countermeasures against direct lightning flash, enhancing equipotential bonding and shielding measures and so forth. 展开更多
关键词 Waterway transportation SHIP Lightning accident COUNTERMEASURES China
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IFCB时变特性约束的多频GPS/Galileo/BDS-3的PPP算法
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作者 路阳阳 祝会忠 +2 位作者 李博 李军 徐爱功 《测绘学报》 北大核心 2025年第2期233-247,共15页
多频高精度定位中需要考虑新频率对定位性能的影响。传统相位频间钟偏差(inter frequency clock bias,IFCB)处理方法受制于参考站数量,且与接收机和卫星相关的硬件延迟相关,影响多频精密单点定位(precision point positioning,PPP)的可... 多频高精度定位中需要考虑新频率对定位性能的影响。传统相位频间钟偏差(inter frequency clock bias,IFCB)处理方法受制于参考站数量,且与接收机和卫星相关的硬件延迟相关,影响多频精密单点定位(precision point positioning,PPP)的可靠性和准确性。针对IFCB对多全球导航卫星系统(global navigation satellite system,GNSS)多频PPP的影响,本文提出了基于测站IFCB观测值提取功率谱密度(power spectral density,PSD)的算法,进一步构建IFCB参数时变特性约束的多频PPP算法,并全面分析了IFCB的时变特性和不同IFCB模型对非差非组合PPP性能的影响。试验结果表明:依据测站IFCB观测值提取IFCB功率谱密度可行且有效。相较于忽略IFCB方法,采用PSD约束的随机模型估计IFCB,PPP在收敛时间提升最大,提升46.51%,采用iGMAS产品和CNES产品平均提升43.54%、34.50%,三维定位精度分别提升41.68%、32.24%、24.64%。并且,将IFCB采用时变特性约束的随机模型参数优化方案能真实地反映IFCB变化。因此,在多GNSS多频PPP处理中,将IFCB参数采用时变特性约束的随机模型参数优化方案能够加快位置收敛速度,提升定位精度,优于产品改正方法,更有利于实时多频PPP的应用。 展开更多
关键词 三频 PPP 多GNSS 随机游走 IFCB 时变特征
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基于Solidworks Flow Simulation的换热器翅片形状对换热量影响研究
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作者 张蓬菲 李俊 +2 位作者 孙丽婷 张慧跃 张宇 《山东化工》 2025年第7期205-209,共5页
利用Solidworks Flow Simulation软件,对不同翅片形状的翅片管式换热器进行数值模拟研究,探讨了在相同翅片面积、不考虑翅片厚度的前提下,翅片形状分别为正三角形、正方形、正六边形、正八边形、圆形时换热量的差异。通过建立不同翅片... 利用Solidworks Flow Simulation软件,对不同翅片形状的翅片管式换热器进行数值模拟研究,探讨了在相同翅片面积、不考虑翅片厚度的前提下,翅片形状分别为正三角形、正方形、正六边形、正八边形、圆形时换热量的差异。通过建立不同翅片形状的翅片管式换热器三维模型,设定合理的边界条件和物理属性,在保证其他所有物理参数、材料属性保持不变的前提下,分析了不同翅片形状的翅片管式换热器的热传递过程,计算出热交换系数、热通量、壁面温度、流体平均温度等数值,从而总结换热量的差异,归纳出翅片形状带给换热量的影响。研究表明,翅片形状对换热器的换热量有显著影响,若翅片形状为边数更多的正多边形,即翅片更接近于圆形,则换热量更小。换热量趋于稳态后,通过提取相同迭代次数区间的换热量数值,计算区间内换热量数值方差,发现三角形至六边形换热稳定性渐变稳定,从六边形至圆形稳定性逐渐降低。此研究为翅片管式换热器设计优化提供了理论依据。 展开更多
关键词 翅片管式换热器 翅片形状 Solidworks Flow Simulation 换热量 CFD 数值模拟
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区域创新生态系统韧性提升路径研究——基于NCA和动态QCA的组态分析
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作者 袁旭梅 李俊 +1 位作者 张明 张旭 《工业技术经济》 北大核心 2026年第1期43-53,共11页
提升区域创新生态系统韧性是应对外部干扰、推动区域高质量发展的重要手段。本文以2013~2024年我国30个省(区、市)为样本,基于TOE(技术-组织-环境)框架,采用必要条件分析(NCA)与动态定性比较分析(QCA)方法,探究区域创新生态系统韧性的... 提升区域创新生态系统韧性是应对外部干扰、推动区域高质量发展的重要手段。本文以2013~2024年我国30个省(区、市)为样本,基于TOE(技术-组织-环境)框架,采用必要条件分析(NCA)与动态定性比较分析(QCA)方法,探究区域创新生态系统韧性的提升路径及其时空演变规律。研究发现:任何单一条件均不构成高区域创新生态系统韧性的必要条件,但产学研合作与市场环境是驱动区域创新生态系统韧性提升的重要条件;存在4条实现高区域创新生态系统韧性的组态路径,可归纳为“组织-环境”型和“技术-组织-环境”型两类,在特定情况下不同前因条件间存在一定替代关系;时间维度上各组态对结果的充分性解释具有较强的稳健性,空间维度上各组态组内覆盖度均值具有明显的地域异质性。研究从组态视角揭示了区域创新生态系统韧性提升的复杂机理,为各地因地制宜推进韧性建设提供了有益启示。 展开更多
关键词 区域创新生态系统韧性 动态QCA NCA TOE框架 数字基础设施 产学研合作 市场环境 因地制宜
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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel
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作者 GAO Qian li jun +3 位作者 WANG Xianhui CAO Laifu GONG Jian li Bo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期275-282,共8页
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the... Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties. 展开更多
关键词 high temperature annealing heating rate secondary recrystallization grain oriented silicon steel
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隐孢子虫重组蛋白包被抗原的筛选及ELISA方法的建立及初步应用 被引量:3
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作者 李军 唐林生 +7 位作者 彭昊 陶立 潘艳 陈泽祥 许力干 谢永平 杨威 黄维义 《中国预防兽医学报》 CAS CSCD 北大核心 2015年第4期286-290,共5页
为建立检测牛隐孢子虫抗体的间接ELISA方法,本研究将重组表达的隐孢子虫卵囊壁蛋白(COWP)、热休克蛋白70(HSP70)蛋白及COWP-HSP70串联蛋白分别作为包被抗原,进行反应条件的优化,建立了3种间接ELISA检测方法。建立的这3种方法均具有较高... 为建立检测牛隐孢子虫抗体的间接ELISA方法,本研究将重组表达的隐孢子虫卵囊壁蛋白(COWP)、热休克蛋白70(HSP70)蛋白及COWP-HSP70串联蛋白分别作为包被抗原,进行反应条件的优化,建立了3种间接ELISA检测方法。建立的这3种方法均具有较高的特异性和敏感性。与伊氏锥虫,球虫和弓形虫阳性血清均无交叉反应,最低检出血清稀释倍数分别为1∶1600、1∶3200和1∶3200。经过筛选,确定COWP-HSP70串联蛋白为包被抗原的间接ELISA方法为最佳检测方法。以该方法进行的重复性试验结果显示,其批内和批间变异系数分别为3.9%~8.2%和4.7%~8.3%。采用建立的ELISA方法与传统的粪检法分别对174份临床样品进行检测,隐孢子虫感染的检出率分别为9.2%和12.07%,两者符合率为97.13%。本研究建立的以COWPHSP70串联蛋白为包被抗原的牛隐孢子虫间接ELISA检测方法适用于临床牛隐孢子虫感染的检测。 展开更多
关键词 隐孢子虫 卵囊壁蛋白 热休克蛋白70 酶联免疫吸附试验
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掺碳LiFePO_(4)的合成及性能研究 被引量:3
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作者 李军 黄慧民 +2 位作者 魏关锋 夏信德 李大光 《材料导报》 EI CAS CSCD 北大核心 2007年第11期125-126,129,共3页
为提高LiFePO_(4)的电化学性能,通过固相合成法制备了掺碳的LiFePO_4正极材料,并用XRD、SEM、电化学工作站及充放电测试等对样品的性能进行了研究分析。结果表明,少量的碳掺杂并未改变LiFePO_4的晶体结构但显著改善了其电化学性能,LiFeP... 为提高LiFePO_(4)的电化学性能,通过固相合成法制备了掺碳的LiFePO_4正极材料,并用XRD、SEM、电化学工作站及充放电测试等对样品的性能进行了研究分析。结果表明,少量的碳掺杂并未改变LiFePO_4的晶体结构但显著改善了其电化学性能,LiFePO_4/C样品的粒度较小,粒径分布均匀,0.1C首次放电比容量为141.9mAh/g,循环50次后容量下降了11.2mAh/g,以1C倍率首次放电比容量为126.5mAh/g,循环50次后容量保持率为87.2%。 展开更多
关键词 锂离子电池 正极材料 磷酸铁锂 掺杂
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铝热还原TiO2制备Magnéli相低价钛氧化物工艺及过程机制研究 被引量:6
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作者 李军 鲁雄刚 +3 位作者 杨绍利 吴恩辉 侯静 李重河 《稀有金属》 EI CAS CSCD 北大核心 2018年第6期627-633,共7页
Magnéli相(TinO2n-1)(4〈n〈10)低价钛氧化物材料具有导电性好、可见光响应强、耐磨、优异的耐腐蚀性能等,被广泛应用于制备电池、惰性电极及光催化降解材料。在空气气氛下利用铝还原锐钛矿相TiO2制备Magnéli相低价钛氧... Magnéli相(TinO2n-1)(4〈n〈10)低价钛氧化物材料具有导电性好、可见光响应强、耐磨、优异的耐腐蚀性能等,被广泛应用于制备电池、惰性电极及光催化降解材料。在空气气氛下利用铝还原锐钛矿相TiO2制备Magnéli相低价钛氧化物材料,研究了不同焙烧温度、焙烧时间和配铝量等工艺参数对制备黑色Magnéli相低价钛氧化物复合材料相变过程的影响,并采用X射线衍射(XRD)、拉曼光谱(Raman)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)等分析手段对制备出的Magnéli相低价氧化物复合材料的物相组成变化及微观组织形貌进行表征,结果表明:不同焙烧温度和焙烧时间下制备的样品主要物相为Ti9O17,Ti8O15,Ti7O13,Ti4O7,随着焙烧温度的升高和焙烧时间的延长,还原程度不断加深,TinO2n-1中的n值不断降低。制备的Magnéli相低价氧化物材料呈颗粒状,粒径200~400 nm左右。通过稀盐酸浸出,可以将Magnéli相材料中过剩的铝除去得到较为纯净的Magnéli相TinO2n-1材料。 展开更多
关键词 铝热还原 TinO2n-1 Magnéli相
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三七总皂苷通过调节Beclin1表达抑制氧化应激诱导的内皮细胞自噬机制 被引量:2
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作者 董艳 李军 +2 位作者 张振鹏 刘咏梅 王阶 《中华中医药杂志》 CAS CSCD 北大核心 2023年第10期4683-4687,共5页
目的:研究三七总皂苷(PNS)抗氧化应激诱导的血管内皮细胞自噬作用机制。方法:将人脐静脉内皮细胞(HUVECs)分为空白组、模型组和治疗组,运用qRT-PCR和Western blot检测自噬蛋白6(Beclin1)、自噬蛋白5(Atg5)mRNA和蛋白表达及细胞自噬流情... 目的:研究三七总皂苷(PNS)抗氧化应激诱导的血管内皮细胞自噬作用机制。方法:将人脐静脉内皮细胞(HUVECs)分为空白组、模型组和治疗组,运用qRT-PCR和Western blot检测自噬蛋白6(Beclin1)、自噬蛋白5(Atg5)mRNA和蛋白表达及细胞自噬流情况;利用透射电子显微镜观察细胞自噬小体形成情况。结果:与空白组比较,模型组能促进自噬小体形成,增加自噬相关膜的合成,上调Beclin1 mRNA和蛋白表达(P<0.05,P<0.01),同时提高Atg5蛋白水平(P<0.01),下调Atg5 mRNA表达(P<0.01)。与模型组比较,治疗组能抑制自噬小体形成,减少细胞自噬流和自噬相关膜合成,并显著下调Beclin1 mRNA和蛋白表达水平(P<0.05),上调Atg5 mRNA表达(P<0.01)。结论:PNS可以通过抑制Beclin1 mRNA及蛋白表达水平,抑制细胞自噬小体和自噬流,从而发挥抗H2O2诱导的HUVECs细胞自噬作用。 展开更多
关键词 三七总皂苷 细胞自噬 血管内皮细胞 氧化应激 自噬蛋白6 自噬蛋白5
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Mobility-Aware User Scheduling in Wireless Federated Learning with Contextual Multi-Armed Bandit
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作者 li jun Sun Haiyang +4 位作者 Deng Xiumei Wei Kang Shi Long liang Le Chen Wen 《China Communications》 2025年第11期256-272,共17页
Federated learning(FL)is an intricate and privacy-preserving technique that enables distributed mobile devices to collaboratively train a machine learning model.However,in real-world FL scenarios,the training performa... Federated learning(FL)is an intricate and privacy-preserving technique that enables distributed mobile devices to collaboratively train a machine learning model.However,in real-world FL scenarios,the training performance is affected by a combination of factors such as the mobility of user devices,limited communication and computational resources,thus making the user scheduling problem crucial.To tackle this problem,we jointly consider the user mobility,communication and computational capacities,and develop a stochastic optimization problem to minimize the convergence time.Specifically,we first establish a convergence bound on the training performance based on the heterogeneity of users’data,and then leverage this bound to derive the participation rate for each user.After deriving the user-specific participation rate,we aim to minimize the training latency by optimizing user scheduling under the constraints of the energy consumption and participation rate.Afterward,we transform this optimization problem to the contextual multi-armed bandit framework based on the Lyapunov method and solve it with the submodular reward enhanced linear upper confidence bound(SR-linUCB)algorithm.Experimental results demonstrate the superiority of our proposed algorithm on the training performance and time consumption compared with stateof-the-art algorithms for both independent and identically distributed(IID)and non-IID settings. 展开更多
关键词 contextual multi-armed bandit federated learning resource allocation upper confidence bound user scheduling
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Enhanced Lithofacies Classification of Tight Sandstone Reservoirs Using a Hybrid CNN-GRU Model with BSMOTE and Heat Kernel Imputation
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作者 li Pan Meng Jia-bing +1 位作者 li jun Chen Qi-jing 《Applied Geophysics》 2025年第4期1141-1157,1495,1496,共19页
Accurate lithofacies classification in low-permeability sandstone reservoirs remains challenging due to class imbalance in well-log data and the difficulty of the modeling vertical lithological dependencies.Traditiona... Accurate lithofacies classification in low-permeability sandstone reservoirs remains challenging due to class imbalance in well-log data and the difficulty of the modeling vertical lithological dependencies.Traditional core-based interpretation introduces subjectivity,while conventional deep learning models often fail to capture stratigraphic sequences effectively.To address these limitations,we propose a hybrid CNN–GRU framework that integrates spatial feature extraction and sequential modeling.Heat Kernel Imputation is applied to reconstruct missing log data,and Borderline SMOTE(BSMOTE)improves class balance by augmenting boundary-case minority samples.The CNN component extracts localized petrophysical features,and the GRU component captures depth-wise lithological transitions,to enable spatial-sequential feature fusion.Experiments on real-well datasets from tight sandstone reservoirs show that the proposed model achieves an average accuracy of 93.3%and a Macro F1-score of 0.934.It outperforms baseline models,including RF(87.8%),GBDT(81.8%),CNN-only(87.5%),and GRU-only(86.1%).Leave-one-well-out validation further confirms strong generalization ability.These results demonstrate that the proposed approach effectively addresses data imbalance and enhances classification robustness,offering a scalable and automated solution for lithofacies interpretation under complex geological conditions. 展开更多
关键词 Lithofacies Classification Deep Learning CNN-GRU Model Imbalanced data processing Heat kernel Imputation
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Unified Bandwidth Scheduling in Centralized Fixed Access Network(C-FAN)
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作者 li jun Lu Xiang +3 位作者 Wang Xiang Chang Tianghai Sanjay Kumar Bose Shen Gangxiang 《China Communications》 2025年第1期196-215,共20页
Time Division Multiplexing-Passive Optical Networks(TDM-PONs)play a vital role in Fiberto-the-Home(FTTH)deployments.To improve the service quality of home networks,FTTH is expanding to the Fiber-to-the-Room(FTTR)scena... Time Division Multiplexing-Passive Optical Networks(TDM-PONs)play a vital role in Fiberto-the-Home(FTTH)deployments.To improve the service quality of home networks,FTTH is expanding to the Fiber-to-the-Room(FTTR)scenario,where fibers are deployed to connect individual rooms(i.e.,Fiber In-premises Network(FIN)in the ITU-T G.9940 standard).In this scenario,a point-to-multipoint(P2MP)fiber network is deployed as FTTR FIN to offer gigabit access to each room,which forms a two-tier cascaded network together with the FTTH segment.To optimize the capacity utilization of the cascaded network and reduce the overall system cost,a centralized architecture,known as Centralized Fixed Access Network(C-FAN),has been introduced.C-FAN centralizes the medium access control(MAC)modules of both the FTTH and FTTR networks at the FTTH’s Optical Line Terminal(OLT)for unified control and management of the cascaded network.We develop a unified bandwidth scheduling protocol by extending the ITU-T PON standard for both the upstream and downstream directions of C-FAN.We also propose a unified dynamic bandwidth allocation(UDBA)algorithm for efficient bandwidth allocation for multiple traffic flows in the two-tier cascaded network.Simulations are conducted to evaluate the performance of the proposed control protocol and the UDBA algorithm.The results show that,in comparison to the conventional DBA algorithm,the UDBA algorithm can utilize upstream bandwidth more efficiently to reduce packet delay and loss,without adversely impacting downstream transmission performance. 展开更多
关键词 ARCHITECTURE dynamic bandwidth allocation FTTH FTTR PON
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Microstructure evolution and mechanical properties of 2195 Al-Li alloy with different heat-treatment states via friction stir additive manufacturing
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作者 GAO Yong-hui JIANG Tao +5 位作者 DAI Guo-qing li jun GUO Yan-hua SUN Zhong-gang liU Chun-hui ZHAN li-hua 《Journal of Central South University》 2025年第11期4159-4179,共21页
Friction stir additive manufacturing(FSAM)is an innovative additive manufacturing(AM)method.The various heat treatment conditions of aluminum-lithium alloys using this method have not been widely discussed.In this stu... Friction stir additive manufacturing(FSAM)is an innovative additive manufacturing(AM)method.The various heat treatment conditions of aluminum-lithium alloys using this method have not been widely discussed.In this study,the microstructure evolution and mechanical properties of FSAM 2195 aluminum-lithium alloy in different heat treatment conditions(T3 and T8)were investigated.The results demonstrated that the heat treatment state of 2195 Al-Li alloys was minimally influenced by FSAM as the FSAM temperature exceeded the solid solution temperature.After conducting a single-pass FSAM experiment,a notable grain refinement was observed in the nugget zone(NZ)region compared to the base material(BM).The average grain size of the 2195-T3 alloy decreased from 6.1 to 2.9µm,while the proportion of high-angle grain boundaries increased from 16.5%to 43.9%.Similarly,the average grain size of the 2195-T8 alloy decreased from 8.9 to 2.8µm,with an increase in high-angle grain boundary from 37.6%to 59.2%.The tensile strength of the 2195-T3 Al-Li alloy reached 466 and 478 MPa in the NZ of single-pass and lap experiments,respectively.In comparison,the tensile strength of the 2195-T8 Al-Li alloy in the NZ could reach 452 and 481 MPa in single-pass and lap experiments,respectively.These results demonstrate the significant improvements in microstructure and mechanical properties were achieved through the FSAM process. 展开更多
关键词 2195 Al-Li alloys friction stir additive manufacturing microstructure evolution MICROHARDNESS
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Application of interval type-2 TSK FLS method based on IGWO algorithm in short-term photovoltaic power forecasting
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作者 li jun ZENG Yuxiang 《Journal of Measurement Science and Instrumentation》 2025年第2期258-271,共14页
For short-term PV power prediction,based on interval type-2 Takagi-Sugeno-Kang fuzzy logic systems(IT2 TSK FLS),combined with improved grey wolf optimizer(IGWO)algorithm,an IGWO-IT2 TSK FLS method was proposed.Compare... For short-term PV power prediction,based on interval type-2 Takagi-Sugeno-Kang fuzzy logic systems(IT2 TSK FLS),combined with improved grey wolf optimizer(IGWO)algorithm,an IGWO-IT2 TSK FLS method was proposed.Compared with the type-1 TSK fuzzy logic system method,interval type-2 fuzzy sets could simultaneously model both intra-personal uncertainty and inter-personal uncertainty based on the training of the existing error back propagation(BP)algorithm,and the IGWO algorithm was used for training the model premise and consequent parameters to further improve the predictive performance of the model.By improving the gray wolf optimization algorithm,the early convergence judgment mechanism,nonlinear cosine adjustment strategy,and Levy flight strategy were introduced to improve the convergence speed of the algorithm and avoid the problem of falling into local optimum.The interval type-2 TSK FLS method based on the IGWO algorithm was applied to the real-world photovoltaic power time series forecasting instance.Under the same conditions,it was also compared with different IT2 TSK FLS methods,such as type I TSK FLS method,BP algorithm,genetic algorithm,differential evolution,particle swarm optimization,biogeography optimization,gray wolf optimization,etc.Experimental results showed that the proposed method based on IGWO algorithm outperformed other methods in performance,showing its effectiveness and application potential. 展开更多
关键词 photovoltaic power interval type-2 fuzzy logic system grey wolf optimizer algorithm forecast performance of model
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Design and Application of an Intelligent Control System for Ceramic Kiln Exhaust Covers Based on 5G and IoT Technology
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作者 ZHAO Zengyi li Tao +1 位作者 YU Zhongzhan li jun 《International Journal of Plant Engineering and Management》 2025年第3期146-160,共15页
Based on 5G and IoT technology,this study addresses the issues of manual control dependency,poor reliability,and high labor costs in traditional ceramic kiln exhaust cover operations.An intelligent control system for ... Based on 5G and IoT technology,this study addresses the issues of manual control dependency,poor reliability,and high labor costs in traditional ceramic kiln exhaust cover operations.An intelligent control system for kiln exhaust covers was designed in this paper.The system employs temperature measurement devices to monitor the internal temperature of the kiln in real time.A controller automatically operates the actuator to open or close the kiln exhaust cover based on temperature measurements.Additionally,the system integrates data transmission units and cloud services,enabling remote monitoring of kiln temperature and historical data storage.Experimental results demonstrate that the system effectively reduces labor costs and significantly enhances the IoT capabilities of kiln operations. 展开更多
关键词 5G IoT ceramic kiln exhaust cover automatic control
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Generalized Quadrature Spatial Modulation for STAR-RIS Aided NOMA Networks
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作者 Guo Yonghao Dang Shuping +3 位作者 li jun Shang Wenli Hou Jia Huang Yu 《China Communications》 2025年第4期1-12,共12页
The simultaneously transmitting and reflecting reconfigurable intelligent surface(STAR-RIS)is regarded as a promising paradigm for enhancing the connectivity and reliability of non-orthogonal multiple access(NOMA)netw... The simultaneously transmitting and reflecting reconfigurable intelligent surface(STAR-RIS)is regarded as a promising paradigm for enhancing the connectivity and reliability of non-orthogonal multiple access(NOMA)networks.However,the transmission of STAR-RIS enhanced NOMA networks performance is severely limited due to the inter-user interference(IUI)on multi-user detections.To mitigate this drawback,we propose a generalized quadrature spatial modulation(GQSM)aided STAR-RIS in conjunction with the NOMA scheme,termed STARRIS-NOMA-GQSM,to improve the performance of the corresponding NGMA network.By STAR-RISNOMA-GQSM,the information bits for all users in transmission and reflection zones are transmitted via orthogonal signal domains to eliminate the IUI so as to greatly improve the system performance.The lowcomplexity detection and upper-bounded bit error rate(BER)of STAR-RIS-NOMA-GQSM are both studied to evaluate its feasibility and performance.Moreover,by further utilizing index modulation(IM),we propose an enhanced STAR-RIS-NOMA-GQSM scheme,termed E-STAR-RIS-NOMA-GQSM,to enhance the transmission rate by dynamically adjusting reflection patterns in both transmission and reflection zones.Simulation results show that the proposed original and enhanced scheme significantly outperform the conventional STAR-RIS-NOMA and also confirm the precision of the theoretical analysis of the upper-bounded BER. 展开更多
关键词 index modulation NOMA STAR-RIS
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Local Geomagnetic Component Modeling of Auroral Images Based on Local‑Global Feature
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作者 WANG Bo ZHANG Yuanshu +5 位作者 CHENG Wei TIAN Xinqin SHENG Qinghong li jun liNG Xiao liU Xiang 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第6期710-727,共18页
Accurately predicting geomagnetic field is of great significance for space environment monitoring and space weather forecasting worldwide.This paper proposes a vision Transformer(ViT)hybrid model that leverages aurora... Accurately predicting geomagnetic field is of great significance for space environment monitoring and space weather forecasting worldwide.This paper proposes a vision Transformer(ViT)hybrid model that leverages aurora images to predict local geomagnetic station component,breaking the spatial limitations of geomagnetic stations.Our method utilizes the ViT backbone model in combination with convolutional networks to capture both the large-scale spatial correlation and distinct local feature correlation between aurora images and geomagnetic station data.Essentially,the model comprises a visual geometry group(VGG)image feature extraction network,a ViT-based encoder network,and a regression prediction network.Our experimental findings indicate that global features of aurora images play a more substantial role in predicting geomagnetic data than local features.Specifically,the hybrid model achieves a 39.1%reduction in root mean square error compared to the VGG model,a 29.5%reduction compared to the ViT model and a 35.3%reduction relative to the residual network(ResNet)model.Moreover,the fitting accuracy of the model surpasses that of the VGG,ViT,and ResNet models by 2.14%1.58%,and 4.1%,respectively. 展开更多
关键词 ultraviolet aurora image geomagnetic field prediction vision Transformer(ViT)hybrid model
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铝热还原法制备Magnéli相亚氧化钛及其可见光光催化活性研究 被引量:1
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作者 李军 吴恩辉 +4 位作者 侯静 黄平 蒋燕 徐众 刘黔蜀 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2020年第7期2281-2288,共8页
采用铝热还原-盐酸酸洗工艺成功制备了Magnéli相亚氧化钛,通过XRD,SEM,UV-Vis DRS和XPS等手段进行表征。结果表明:在焙烧温度950℃,焙烧时间20 min,Al/TiO2=0.2时,成功制备以Ti4O7为主要物相的Magnéli相亚氧化钛材料,其粒径为... 采用铝热还原-盐酸酸洗工艺成功制备了Magnéli相亚氧化钛,通过XRD,SEM,UV-Vis DRS和XPS等手段进行表征。结果表明:在焙烧温度950℃,焙烧时间20 min,Al/TiO2=0.2时,成功制备以Ti4O7为主要物相的Magnéli相亚氧化钛材料,其粒径为400~600 nm,样品表面形成了大量的氧空位,表现出很强的紫外和可见光吸收性能。在可见光条件下光照130 min时,950℃焙烧20、25和35 min条件下制备并酸洗后的Magnéli相亚氧化钛降解亚甲基蓝的效率分别达到37%、43%和62%。 展开更多
关键词 铝热还原 Magnéli相 光催化降解
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VARIAN Eclipse治疗计划中PBC和AAA算法在直肠癌调强放疗中的剂量学研究比较 被引量:4
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作者 褚俊峰 李军 +5 位作者 桂龙刚 张西志 张先稳 陈永东 孙新臣 李金凯 《肿瘤基础与临床》 2018年第4期311-315,共5页
目的比较VARIAN Eclipse计划系统中笔形束卷积(PBC)和各向异性(AAA)算法在直肠癌调强放疗(IMAT)中的剂量学差异,并进行剂量验证。方法随机选取20例直肠癌放疗患者,并在VARIAN Eclipse系统中分别采用PBC算法和AAA算法设计IMRT治疗计划,... 目的比较VARIAN Eclipse计划系统中笔形束卷积(PBC)和各向异性(AAA)算法在直肠癌调强放疗(IMAT)中的剂量学差异,并进行剂量验证。方法随机选取20例直肠癌放疗患者,并在VARIAN Eclipse系统中分别采用PBC算法和AAA算法设计IMRT治疗计划,并利用PTW 729二维剂量验证系统成相应的验证计划,比较靶区及危及器官(OARs)的剂量学参数差异。结果 2种算法模型下,都能满足临床要求,但两者对靶区和OARs的差异影响是比较明显的。对临床靶区(CTV)和计划靶区(PTV)而言,AAA算法模型下的D2%、D5%、D50%、D95%、D98%、Dmean较PBC算法模型更高(P均<0. 05),且CTV的剂量适形度指数和PTV的剂量均匀性指数更好(P均<0. 05);从保护OARs的角度而言,PBC算法模型条件下的小肠Dmax、脊髓Dmax和膀胱D50%较AAA算法模型更低(P均<0. 05);剂量验证中,对整个计划而言,2种算法模型下的γ通过率均能达到95%,都能达满足临床要求(P> 0. 05)。结论对于基于Eclipse系统的直肠癌IMRT计划而言,AAA算法整体上能获得更好的靶区剂量分布,更有利于肿瘤的治疗,但PBC算法却更能保护OARs,降低放疗不良反应。 展开更多
关键词 直肠癌 调强放疗 AAA算法 PBC算法 剂量学参数
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