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Optimizing polyphase sequences for orthogonal netted radar systems 被引量:5
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作者 Wenwu Chen Zhengyu Cai +1 位作者 Rushan Chen Zhao Zhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第4期529-535,共7页
Orthogonal netted radar systems (ONRS) can fundamentally improve the radar performance by using a group of specially designed orthogonal polyphase code signals which require a very low aperiodic autocorrelation peak... Orthogonal netted radar systems (ONRS) can fundamentally improve the radar performance by using a group of specially designed orthogonal polyphase code signals which require a very low aperiodic autocorrelation peak sidelobe level, low aperiodic cross-correlation, and a good resilience to small Doppler shifts. However, the existing numerical solutions degrade severely in the presence of small Doppler shifts. A new set of polyphase sequences is presented with good correlation properties as well as resilience to Doppler shifts. These sequences are built by using numerical optimization based on correlation properties as well as the Doppler effects on matched filter outputs, which maintains the Doppler tolerance. The statistical simulated annealing algorithm and the greedy code search method are used to optimize the sequences. Correlation and Doppler results are compared with the best-known sequences and show to be superior. 展开更多
关键词 Doppler resilience netted radar orthogonal polyphasecode simulated annealing (SA).
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Adaptive allocation strategy for cooperatively jamming netted radar system based on improved cuckoo search algorithm 被引量:2
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作者 De-jiang Lu Xing Wang +1 位作者 Xiao-tian Wu You Chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期285-297,共13页
The jamming resource allocation problem of the aircraft formation cooperatively jamming netted radar system is investigated.An adaptive allocation strategy based on dynamic adaptive discrete cuckoo search algorithm(DA... The jamming resource allocation problem of the aircraft formation cooperatively jamming netted radar system is investigated.An adaptive allocation strategy based on dynamic adaptive discrete cuckoo search algorithm(DADCS)is proposed,whose core is to adjust allocation scheme of limited jamming resource of aircraft formation in real time to maintain the best jamming effectiveness against netted radar system.Firstly,considering the information fusion rules and different working modes of the netted radar system,a two-factor jamming effectiveness evaluation function is constructed,detection probability and aiming probability are adopted to characterize jamming effectiveness against netted radar system in searching and tracking mode,respectively.Then a nonconvex optimization model for cooperatively jamming netted radar system is established.Finally,a dynamic adaptive discrete cuckoo search algorithm(DADCS)is constructed by improving path update strategies and introducing a global learning mechanism,and a three-step solution method is proposed subsequently.Simulation results are provided to demonstrate the advantages of the proposed optimization strategy and the effectiveness of the improved algorithm. 展开更多
关键词 Cuckoo search algorithm netted radar system Radar countermeasures Resource allocation Information fusion
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Joint target assignment and power allocation in the netted C-MIMO radar when tracking multi-targets in the presence of self-defense blanket jamming 被引量:1
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作者 Zhengjie Li Junwei Xie +1 位作者 Haowei Zhang Jiahao Xie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期414-427,共14页
The netted radar system(NRS)has been proved to possess unique advantages in anti-jamming and improving target tracking performance.Effective resource management can greatly ensure the combat capability of the NRS.In t... The netted radar system(NRS)has been proved to possess unique advantages in anti-jamming and improving target tracking performance.Effective resource management can greatly ensure the combat capability of the NRS.In this paper,based on the netted collocated multiple input multiple output(CMIMO)radar,an effective joint target assignment and power allocation(JTAPA)strategy for tracking multi-targets under self-defense blanket jamming is proposed.An architecture based on the distributed fusion is used in the radar network to estimate target state parameters.By deriving the predicted conditional Cramer-Rao lower bound(PC-CRLB)based on the obtained state estimation information,the objective function is formulated.To maximize the worst case tracking accuracy,the proposed JTAPA strategy implements an online target assignment and power allocation of all active nodes,subject to some resource constraints.Since the formulated JTAPA is non-convex,we propose an efficient two-step solution strategy.In terms of the simulation results,the proposed algorithm can effectively improve tracking performance in the worst case. 展开更多
关键词 netted radar system MIMO Target assignment Power allocation Multi-targets tracking Self-defense blanket jamming
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ECCM schemes in netted radar system based ontemporal pulse diversity 被引量:1
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作者 ahmed abdalla zhao yuan bin tang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1001-1009,共9页
For a netted radar system to counteract the deceptionelectronic countermeasure (ECM) signals, an effective electroniccounter countermeasure (ECCM) approach is proposed. The proposedapproach is realized based on th... For a netted radar system to counteract the deceptionelectronic countermeasure (ECM) signals, an effective electroniccounter countermeasure (ECCM) approach is proposed. The proposedapproach is realized based on the new signaling strategyfor the temporal pulse diversity, which makes use of transmittingpulses at each pulse repetition interval (PRI) with specific transmissionpulse block, and then following proper processing andinformation fusion. The existence of the deceptive ECM signal isconfirmed by one station, while the other stations in the nettedradar with same parameters applied the pulse diversity skillfully.Meanwhile, this method ensured that, pulse diversity can be appliedin netted radar. The performance assessment shows that theproposed solutions are effective in presence of ECM signals. Thisalgorithm has been demonstrated by simulations. The presentedsimulation results are in excellent consensus with theoretical predictions. 展开更多
关键词 pulse diversity electronic counter countermeasure(ECCM) digital radio frequency memory (DRFM) electronic countermeasure(ECM) netted radar matching filter.
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Fabrication and formation mechanism of NbC_x-C three-dimensional netted fibers
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作者 GuiyingXu JianbaoLi 《Journal of University of Science and Technology Beijing》 CSCD 2002年第2期121-126,共6页
Micrometer NbC_x-C three-dimensional netted fibers were synthesized by thecarbothermal method under 0.1 MPa of N_2 ambient atmosphere at a relatively low temperature. Rawmaterials were commercial powders of Nb_2O_5 (9... Micrometer NbC_x-C three-dimensional netted fibers were synthesized by thecarbothermal method under 0.1 MPa of N_2 ambient atmosphere at a relatively low temperature. Rawmaterials were commercial powders of Nb_2O_5 (99.95 percent), reactive carbon (99.99 percent), NaCl(99.95 percent) and sucrose (99.94 percent). The relationship of the fabrication processing with thecomposition, crystal structure and morphology of fibers was investigated. The formation mechanismwas also proposed and discussed. 展开更多
关键词 NbC_x-C three-dimensional netted fibers FABRICATION MORPHOLOGY formation mechanism
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720 000--meter Plastic Netted Steel Framework Composite Pipe Project
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《China Oil & Gas》 CAS 1998年第2期119-119,共1页
关键词 meter Plastic netted Steel Framework Composite Pipe Project
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Fabrication and morphology of NbC_x-C composite three-dimensinal netted fibers
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作者 Guiying Xu Jianbao Li Yong Huang 《Chinese Science Bulletin》 SCIE EI CAS 2000年第6期496-502,共7页
The raw materials were commercial powders of Nb2O5 (99.95%), reactive carbon (99.99%), NaCI (99.95%) and sucrose (99.94%). By the carbothermal method, the NbCx (x= 0.98)-C composite three-dimensional netted fibers wer... The raw materials were commercial powders of Nb2O5 (99.95%), reactive carbon (99.99%), NaCI (99.95%) and sucrose (99.94%). By the carbothermal method, the NbCx (x= 0.98)-C composite three-dimensional netted fibers were prepared in graphite resistance furnace in 0.1 MPa/N2 ambient atmosphere at temperature from 970 to 1 120℃. The diameters of composite three-dimensional netted fibers are 12-38 μm, the hole circumferences of netted fibers are 0.22-2.2 mm, and the hole diameters are 70-701 μm. The process conditions for fabricating NbCx-C composite three-dimensional netted fibers and related morphology, composition and crystal structure of NbCx-C composite netted fibers were investigated in detail. 展开更多
关键词 FABRICATION MORPHOLOGY NBC -C COMPOSITE THREE-DIMENSIONAL netted fibers carbothermal method.
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Assembly, crystal structure, and luminescent properties of three-dimensional (10,3)-a netted rare earth coordination polymers
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作者 TANG Yu TANG KuanZhen +1 位作者 LIU WeiSheng TAN MinYu 《Science China Chemistry》 SCIE EI CAS 2008年第7期614-622,共9页
Solid complexes [REL(NO3)3]n with novel (10,3)-a type three-dimensional networks structure have been assembled using rare earth nitrates and an amide type semirigid tripodal bridging ligand, 1,3,5-tris {[(2′-benzylam... Solid complexes [REL(NO3)3]n with novel (10,3)-a type three-dimensional networks structure have been assembled using rare earth nitrates and an amide type semirigid tripodal bridging ligand, 1,3,5-tris {[(2′-benzylaminoformyl)phenoxyl]methyl}benzene (L), as building blocks. The complexes were crys- tallized in the orthorhombic system with chiral space group P212121. The whole structure consists of an infinite array of trigonal RE(III) ions bridged by tridentate ligands, and a novel (10,3)-a net is formed, which is very uncommon in the rare earth complexes. At room temperature, the Sm(III), Eu(III), Tb(III), Dy(III) complexes all exhibited characteristic luminescence emissions of central metal ions under UV light excitation. 展开更多
关键词 amide-type TRIPODAL bridge LIGAND rare earth NITRATE (10 3)-a netted coordination polymer luminecent properties
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NETs在脓毒症凝血功能障碍中的作用研究进展
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作者 李淑芳 熊旭东 《岭南急诊医学杂志》 2024年第4期443-446,共4页
脓毒症凝血功能障碍是脓毒症患者死亡的主要原因之一。炎症反应和凝血功能障碍相互促进、相互影响是影响脓毒症预后的重要因素。NETs是活化中性粒细胞分泌的网状结构,在脓毒症炎症和凝血中起桥梁作用。本文从NETs形成,NETs与血管内皮细... 脓毒症凝血功能障碍是脓毒症患者死亡的主要原因之一。炎症反应和凝血功能障碍相互促进、相互影响是影响脓毒症预后的重要因素。NETs是活化中性粒细胞分泌的网状结构,在脓毒症炎症和凝血中起桥梁作用。本文从NETs形成,NETs与血管内皮细胞、凝血因子、血小板关系及针对NETs开展的相关药物研究等方面进行综述,为进一步探索干预脓毒症凝血功能障碍的方法提供理论依据。 展开更多
关键词 NETS 脓毒症 血管内皮细胞 凝血因子 血小板
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Medical ozone alleviates acute lung injury by enhancing phagocytosis targeting NETs via AMPK/SR-A1 axis 被引量:1
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作者 Chenxiao Yan Yong Zhang +10 位作者 Lai Jin Xiaojie Liu Xuexian Zhu Qifeng Li Yu Wang Liang Hu Xueming He Hongguang Bao Xia Zhu Qian Wang Wen-Tao Liu 《Journal of Biomedical Research》 CAS CSCD 2024年第6期569-584,共16页
Acute lung injury(ALI)linked to sepsis has a high mortality rate,with limited treatment options available.In recent studies,medical ozone has shown the potential to alleviate inflammation and infection.Here,we aimed t... Acute lung injury(ALI)linked to sepsis has a high mortality rate,with limited treatment options available.In recent studies,medical ozone has shown the potential to alleviate inflammation and infection.Here,we aimed to evaluate therapeutic potential of medical ozone in a mouse model of the sepsis-induced ALI by measuring behavioral assessments,lung function,and blood flow.Protein levels were quantified by Western blotting.In vitro,we performed experiments on bone marrow-derived macrophages(BMDMs)to investigate the effect of adenosine monophosphate(AMP)-activated protein kinase(AMPK)inhibitors and agonists on their phagocytic activity.The results showed that medical ozone significantly improved the survival rate,ameliorated lung injury,and enhanced lung function and limb microcirculation in mice with ALI.Notably,medical ozone inhibited the formation of neutrophil extracellular traps(NETs),a crucial factor in the ALI development.Additionally,medical ozone counteracted the elevated levels of tissue factor,matrix metalloproteinase-9,and interleukin-1β.In the ALI mice,the effects of ozone were abolished,and BMDMs showed an impaired capacity to engulf NETs following the Sr-a1 knockout.Under normal physiological conditions,the administration of an AMPK antagonist showed similar effects on the Sr-a1 knockout,significantly inhibiting the phagocytosis of NETs by BMDMs.In contrast,AMPK agonists enhanced this phagocytic process.In conclusion,medical ozone may alleviate the sepsis-induced lung injury through the AMPK/SR-A1 pathway,thereby enhancing the phagocytosis of NETs by macrophages. 展开更多
关键词 SR-A1 NETS ALI PHAGOCYTOSIS ozone therapy
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直肠神经内分泌肿瘤的内镜下治疗效果评价分析
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作者 许松欣 段兆涛 李贵庆 《现代消化及介入诊疗》 2024年第4期445-448,共4页
背景对于没有转移危险因素且直径<15 mm直肠神经内分泌肿瘤的患者,推荐行内镜下切除,但其短期和长期结果尚不清楚。目的本研究旨在探讨内镜切除15 mm以内的直肠NETs的疗效。方法分析接受内镜切除治疗的直肠NETs<15 mm患者的短期... 背景对于没有转移危险因素且直径<15 mm直肠神经内分泌肿瘤的患者,推荐行内镜下切除,但其短期和长期结果尚不清楚。目的本研究旨在探讨内镜切除15 mm以内的直肠NETs的疗效。方法分析接受内镜切除治疗的直肠NETs<15 mm患者的短期和长期结果,以及EMR及ESD切除的结果。肿瘤分为<10 mm(小型组)和10~14 mm(中等大小组)两组。结果总共纳入2024年1月~2023年11月扬州大学附属医院消化科90例直肠神经内分泌肿瘤(小型组,n=81;中等大小组,n=9)。根据2019年世界卫生组织分级标准,所有肿瘤均被分为G1(n=88)或G2(n=2)。两组之间完整切除率无显著差异。在小型组中,内镜粘膜下剥离(ESD)和内镜粘膜下切除(EMR)均达到100%的完整切除率。EMR手术时间(P<0.001)和住院时间(P<0.001)显著短于ESD。在中等大小组中,ESD的完整切除率为100%。15 mm以内肿瘤大小不影响总生存率或淋巴结/远处转移率。结论对于没有转移风险因素15 mm以内的直肠NETs患者,内镜切除是可行且有效的治疗方法。对于小于10 mm和10~14 mm的肿瘤,EMR和ESD是最佳的切除技术,分别适用于两种不同大小的肿瘤。 展开更多
关键词 直肠 神经内分泌肿瘤 NETS ESD EMR
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系统性红斑狼疮患者血管内皮细胞损伤影响因素研究进展
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作者 李力 张瑞仙 《医学研究杂志》 2024年第6期168-171,共4页
系统性红斑狼疮(systemic lupus erythematosus,SLE)是一种慢性自身免疫性疾病,主要表现为异常激活的免疫系统攻击自身细胞组织,进而累及全身多系统器官。血管内皮细胞作为SLE免疫攻击的靶标之一,其损伤可进一步引起患者皮肤、心脏、肾... 系统性红斑狼疮(systemic lupus erythematosus,SLE)是一种慢性自身免疫性疾病,主要表现为异常激活的免疫系统攻击自身细胞组织,进而累及全身多系统器官。血管内皮细胞作为SLE免疫攻击的靶标之一,其损伤可进一步引起患者皮肤、心脏、肾脏等重要系统器官的并发症。而引起SLE患者血管内皮细胞损伤的因素众多,主要包括多种免疫细胞及其分泌的细胞因子、血管活性物质、内皮特异性蛋白、活性氧等。同时,也有部分保护因素,如血管生成性T细胞、一氧化氮、褪黑素等能促进血管内皮细胞的修复。本文从上述提及的影响因素进行综述,旨在为SLE血管内皮细胞损伤及其机制的研究提供线索,同时为精准防治SLE提供依据。 展开更多
关键词 系统性红斑狼疮 血管内皮细胞 NETS BLYS 血管活性物质
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HB-Continuous Mappings in L-Topological Space
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作者 Najah A. AlSaedi 《Advances in Pure Mathematics》 2024年第5期333-353,共21页
In this paper, we introduce and study the notion of HB-closed sets in L-topological space. Then, HB-convergence theory for L-molecular nets and L-ideals is established in terms of HB-closedness. Finally, we give a new... In this paper, we introduce and study the notion of HB-closed sets in L-topological space. Then, HB-convergence theory for L-molecular nets and L-ideals is established in terms of HB-closedness. Finally, we give a new definition of fuzzy H-continuous [1] which is called HB-continuity on the basis of the notion of H-bounded L-subsets in L-topological space. Then we give characterizations and properties by making use of HB-converges theory of L-molecular nets and L-ideals. 展开更多
关键词 L-Topological Space HB-Closed Set H-Bounded Set HB-Continuous Mappings HB-Convergence L-Molecular Nets L-Ideals
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基于Deep Belief Nets的中文名实体关系抽取 被引量:72
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作者 陈宇 郑德权 赵铁军 《软件学报》 EI CSCD 北大核心 2012年第10期2572-2585,共14页
关系抽取是信息抽取的一项子任务,用以识别文本中实体之间的语义关系.提出一种利用DBN(deepbelief nets)模型进行基于特征的实体关系抽取方法,该模型是由多层无监督的RBM(restricted Boltzmann machine)网络和一层有监督的BP(back-propa... 关系抽取是信息抽取的一项子任务,用以识别文本中实体之间的语义关系.提出一种利用DBN(deepbelief nets)模型进行基于特征的实体关系抽取方法,该模型是由多层无监督的RBM(restricted Boltzmann machine)网络和一层有监督的BP(back-propagation)网络组成的神经网络分类器.RBM网络以确保特征向量映射达到最优,最后一层BP网络分类RBM网络的输出特征向量,从而训练实体关系分类器.在ACE04语料上进行的相关测试,一方面证明了字特征比词特征更适用于中文关系抽取任务;另一方面设计了3组不同的实验,分别使用正确的实体类别信息、通过实体类型分类器得到实体类型信息和不使用实体类型信息,用以比较实体类型信息对关系抽取效果的影响.实验结果表明,DBN非常适用于基于高维空间特征的信息抽取任务,获得的效果比SVM和反向传播网络更好. 展开更多
关键词 DBN(deep BELIEF nets) 神经网络 关系抽取 深层网络 字特征
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基于不完备信息系统规则提取和Petri Nets的电力变压器故障诊断 被引量:11
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作者 荣雅君 赵杰 +2 位作者 王健 吴闻婧 葛葆华 《电力系统保护与控制》 EI CSCD 北大核心 2009年第18期1-4,10,共5页
鉴于电力变压器故障信息具有不完备性及复杂性,将不完备信息系统规则的提取与Petri Nets(PNs)有机结合在一起进行变压器故障诊断。利用不完备信息规则提取对信息表进行知识的简化与故障特征的压缩,获得最小诊断规则,并利用此规则建造PN... 鉴于电力变压器故障信息具有不完备性及复杂性,将不完备信息系统规则的提取与Petri Nets(PNs)有机结合在一起进行变压器故障诊断。利用不完备信息规则提取对信息表进行知识的简化与故障特征的压缩,获得最小诊断规则,并利用此规则建造PNs的模型。同时利用PNs实现并行推理,对变压器进行快速分析。故障实例分析表明,文中所提出的智能方法具有准确性,有效性。 展开更多
关键词 PETRI NETS 电力变压器 故障诊断 规则提取 不完备信息系统
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Intrusion detection model based on deep belief nets 被引量:6
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作者 高妮 高岭 +2 位作者 贺毅岳 高全力 任杰 《Journal of Southeast University(English Edition)》 EI CAS 2015年第3期339-346,共8页
This paper focuses on the intrusion classification of huge amounts of data in a network intrusion detection system. An intrusion detection model based on deep belief nets (DBN) is proposed to conduct intrusion detec... This paper focuses on the intrusion classification of huge amounts of data in a network intrusion detection system. An intrusion detection model based on deep belief nets (DBN) is proposed to conduct intrusion detection,and the principles regarding DBN are discussed.The DBN is composed of a multiple unsupervised restricted Boltzmann machine (RBM) and a supervised back propagation (BP)network.First,the DBN in the proposed model is pre-trained in a fast and greedy way,and each RBM is trained by the contrastive divergence algorithm.Secondly,the whole network is fine-tuned by the supervised BP algorithm,which is employed for classifying the low-dimensional features of the intrusion data generated by the last RBM layer simultaneously.The experimental results on the KDD CUP 1999 dataset demonstrate that the DBN using the RBM network with three or more layers outperforms the self-organizing maps (SOM)and neural network (NN)in intrusion classification.Therefore,the DBN is an efficient approach for intrusion detection in high-dimensional space. 展开更多
关键词 intrusion detection deep belief nets restricted Boltzmann machine deep learning
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中性粒细胞的功能及其与自身免疫性疾病关联性研究进展 被引量:18
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作者 刘义庆 卢冰如 +1 位作者 张炳昌 赵跃然 《中国免疫学杂志》 CAS CSCD 北大核心 2014年第5期712-716,共5页
中性粒细胞是人体内最主要的固有免疫细胞之一,感染及炎症发生时,在趋化因子作用下第一时间募集到疾病发生位点。细菌、真菌及病毒等病原微生物感染过程中,中性粒细胞通过吞噬杀伤和分泌抗菌物质发挥其固有免疫作用。近年来研究发现... 中性粒细胞是人体内最主要的固有免疫细胞之一,感染及炎症发生时,在趋化因子作用下第一时间募集到疾病发生位点。细菌、真菌及病毒等病原微生物感染过程中,中性粒细胞通过吞噬杀伤和分泌抗菌物质发挥其固有免疫作用。近年来研究发现,中性粒细胞可以分泌多种细胞因子发挥免疫调节作用,中性粒细胞的免疫调节功能越来越受到重视。NETs是新发现的中性粒细胞抗感染机制,能够网络病原菌限制其散播范围,提高局部抗菌物质浓度消除病原菌。中性粒细胞是人体内最重要的炎症介导细胞,其具有在炎症发生过程中趋化、游出、释放炎症介质及蛋白酶类的生物学特性,可以引起广泛的组织损伤。 NETs在发挥胞外抗菌作用的同时,限制各种抗菌性颗粒蛋白的扩散能够减少中性粒细胞引起的组织损伤,但同时NETs的形成及清除障碍会加重某些自身免疫性疾病的严重程度。此外,中性粒细胞分泌的细胞因子、机体抗中性粒细胞胞浆抗体的产生在自身免疫病发病机制中也有重要作用。本文旨在着重对中性粒细胞在感染及炎症中的免疫功能、NETs的功能和形成机制以及中性粒细胞在某些常见自身免疫病发病中的作用进行简单综述。 展开更多
关键词 抗中性粒细胞胞浆抗体 自身免疫性疾病 炎症介质 自身免疫病 NETS 固有免疫细胞 感染过程 免疫调节作用
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新版美国国家教师教育技术标准解读及启示 被引量:12
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作者 吴芸 刘向敏 沈书生 《中国电化教育》 CSSCI 北大核心 2008年第11期5-10,共6页
国际教育技术协会于2008年6月30日公布了新版的美国国家教师教育技术标准,文章针对修订后的标准,从新标准出台的背景、新标准与2000版标准在结构和内容上的对比、新标准更新的亮点以及对我国中小学教师教育技术能力建设所带来的启示等... 国际教育技术协会于2008年6月30日公布了新版的美国国家教师教育技术标准,文章针对修订后的标准,从新标准出台的背景、新标准与2000版标准在结构和内容上的对比、新标准更新的亮点以及对我国中小学教师教育技术能力建设所带来的启示等方面进行探讨。文章认为新版教师教育技术标准的核心在于教师利用数字化工具和资源提升学生的创造力和创新精神。 展开更多
关键词 NETS 教师教育技术标准 创新 数字化
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基于SE-CapsNet的肺结节良恶性诊断研究 被引量:4
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作者 叶枫 王路遥 +2 位作者 洪卫 丁国军 车镓荣 《中国生物医学工程学报》 CAS CSCD 北大核心 2021年第1期71-80,共10页
在过去的几年中,肺癌是癌症相关死亡的主要原因。提出一种针对低剂量计算机断层扫描(CT)影像精细化预处理条件下的SE-CapsNet分类方法,解决传统肺结节诊断方法中分类精度低、假阳性高等问题。改进胶囊神经网络分类算法:对最新Hinton的... 在过去的几年中,肺癌是癌症相关死亡的主要原因。提出一种针对低剂量计算机断层扫描(CT)影像精细化预处理条件下的SE-CapsNet分类方法,解决传统肺结节诊断方法中分类精度低、假阳性高等问题。改进胶囊神经网络分类算法:对最新Hinton的胶囊神经网络进行改进,引入新的非线性激活向量,避免全局向量压缩;采用特征重标定的方法,在特征通道层面进行模型优化。在标定的感兴趣区域,利用自动阈值法对CT影像进行预处理,并在中心结节处进行样本采样,获得预处理结果数据样本。选用内含1 010个病例的公开数据集LIDC-IDRI和某医院30个脱敏肿瘤患者病例,评估改进的SE-CapsNet算法,评价指标包括准确性、敏感性和特异性。在LIDC-IDRI数据集与医院数据集中,SE-CapsNet算法的平均准确率分别达到95.83%和94.67%,优于基于Caps Net分类算法的平均准确率。此外,在分类算法的耗时方面也具有明显优势,改进的胶囊网络能够更快地收敛,得到稳定的结果。 展开更多
关键词 Caps Nets SE-Net 肺结节 CT图像 计算机辅助诊断
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美国国家教师相关标准及其对我国教师信息能力标准制定的启发 被引量:15
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作者 李爽 陈丽 《电化教育研究》 CSSCI 北大核心 2003年第5期68-71,共4页
国内目前为止仍然没有一套国家级的相关教师信息能力标准 ,使得各种教师培训缺乏规范性和统一性。美国在教师培训方面已经进行了长期的实践 ,在教师教育技术和信息技能标准制定方面拥有丰富的经验 ,本文在分析美国国家制定的有关教师能... 国内目前为止仍然没有一套国家级的相关教师信息能力标准 ,使得各种教师培训缺乏规范性和统一性。美国在教师培训方面已经进行了长期的实践 ,在教师教育技术和信息技能标准制定方面拥有丰富的经验 ,本文在分析美国国家制定的有关教师能力标准的基础上 ,探索我国中小学教师信息能力标准制定的相关问题。 展开更多
关键词 NETS CSED 教师信息能力标准
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