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Adaptive allocation strategy for cooperatively jamming netted radar system based on improved cuckoo search algorithm
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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
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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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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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基于中性粒细胞胞外诱捕网探究丹参酮ⅡA对脓毒症小鼠肠损伤的影响及机制 被引量:2
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作者 陈聪敏 张晓慧 +3 位作者 丁新耘 马源 刘澈 马玉清 《中国急救医学》 CAS CSCD 2023年第2期119-125,共7页
目的探究丹参酮ⅡA(TanⅡA)对脓毒症小鼠肠损伤的影响和中性粒细胞胞外诱捕网(NETs)在其中的作用及可能机制。方法24只健康雄性C57BL/6小鼠随机分为对照组(Control组)、脂多糖组(LPS组)、LY294002组(LPS+LY组)、丹参酮ⅡA组(LPS+TanⅡA... 目的探究丹参酮ⅡA(TanⅡA)对脓毒症小鼠肠损伤的影响和中性粒细胞胞外诱捕网(NETs)在其中的作用及可能机制。方法24只健康雄性C57BL/6小鼠随机分为对照组(Control组)、脂多糖组(LPS组)、LY294002组(LPS+LY组)、丹参酮ⅡA组(LPS+TanⅡA组),每组6只。除Control组注射等量磷酸盐缓冲液(PBS)外,其余各组腹腔注射LPS 10 mg/kg建立脓毒症模型。LPS+LY组于造模前30 min腹腔注射LY29400230 mg/kg,LPS+TanⅡA组于造模前30 min腹腔注射TanⅡA 30 mg/kg,其余两组于上述时间点腹腔注射等量PBS[含1‰二甲基亚砜(DMSO)]。给药12 h后采集标本。苏木精-伊红(HE)染色观察小肠组织病理学变化并进行Chiu′s评分;酶联免疫吸附实验(ELISA)检测血清D-乳酸(D-Lac)水平、小肠组织髓过氧化物酶(MPO)-DNA复合物(MPO-DNA)及瓜氨酸化组蛋白H3(CitH3)含量;蛋白免疫印迹法(Western blotting)检测小肠组织闭合蛋白(Claudin)-1、磷酸化(p-)PI3K、磷酸化(p-)Akt蛋白表达。结果与Control组比较,LPS组小鼠小肠组织病理损伤严重;Chiu′s评分升高;血清D-Lac水平上升,小肠组织MPO-DNA、CitH3含量增加Claudin-1蛋白表达减少,p-PI3K、p-Akt蛋白表达增加,差异均有统计学意义(P<0.001)。与LPS组比较,LPS+LY组和LPS+TanⅡA组小鼠小肠组织病理损伤减轻,Chiu′s评分降低(P<0.001),血清D-Lac水平下降(P<0.001),小肠组织MPO-DNA、CitH3含量减少(P<0.001);Claudin-1蛋白表达增加(P<0.05或P<0.001),p-PI3K、p-Akt蛋白表达减少(P<0.01)。结论TanⅡA通过抑制PI3K/Akt信号通路,减少NETs生成,增加Claudin-1蛋白表达,降低肠黏膜通透性,发挥脓毒症小鼠肠损伤的保护作用。 展开更多
关键词 脓毒症 肠损伤 中性粒细胞胞外诱捕网(NETs) 磷脂酰肌醇-3-激酶(PI3K)/蛋白激酶(Akt) 丹参酮ⅡA(TanⅡA) 瓜氨酸化组蛋白H3(CitH3) 闭合蛋白-1(Claudin-1)
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热射病相关生物标志物的研究现状
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作者 廖婵(综述) 李倩(审校) 《锦州医科大学学报》 CAS 2023年第6期108-112,共5页
热射病是临床上病死率较高的疾病,相比于普通中暑,其具有病情进展迅速、病情危重等特点,早期识别、诊断和干预对于提高患者生存率至关重要,相关生物标志物可帮助临床医生快速了解病情,为临床工作提供经验,本文通过查阅相关文献,将就热... 热射病是临床上病死率较高的疾病,相比于普通中暑,其具有病情进展迅速、病情危重等特点,早期识别、诊断和干预对于提高患者生存率至关重要,相关生物标志物可帮助临床医生快速了解病情,为临床工作提供经验,本文通过查阅相关文献,将就热射病细胞、组织损伤与修复相关的生物标志物做一综述。 展开更多
关键词 热射病 组织损伤与修复 HSP70 INOS NETS D-二聚体 细胞间黏附因子
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Boundedness and liveness enforcement for labeled Petri nets using transition priority
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作者 Ye-Jia Liu Xun-Bo Li 《Journal of Electronic Science and Technology》 EI CSCD 2023年第4期75-90,共16页
This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condit... This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condition is given and proven for the existence of a feasible priority-based controller based on the notions of liveness and transition invariants. Next, a cyclic behavior graph is constructed, which shows the reachable markings that guarantee the maximum liveness of the system within a given bound vector. Finally, an on-line control strategy is proposed to enforce boundedness and liveness to the given system by appending priority relations to transitions. The dynamic priority relation changes flexibly according to the current state of the system and enforces the system evolving in a bounded and live manner. In addition, numerical examples are studied to verify the validity of the proposed approach that remains the structure of the plant net and is efficient for on-line control. 展开更多
关键词 BOUNDEDNESS Control strategy LIVENESS Petri nets PRIORITY Transition invariant
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Free form deformation and symmetry constraint‐based multimodal brain image registration using generative adversarial nets
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作者 Xingxing Zhu Mingyue Ding Xuming Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1492-1506,共15页
Multi‐modal brain image registration has been widely applied to functional localisation,neurosurgery and computational anatomy.The existing registration methods based on the dense deformation fields involve too many ... Multi‐modal brain image registration has been widely applied to functional localisation,neurosurgery and computational anatomy.The existing registration methods based on the dense deformation fields involve too many parameters,which is not conducive to the exploration of correct spatial correspondence between the float and reference images.Meanwhile,the unidirectional registration may involve the deformation folding,which will result in the change of topology during registration.To address these issues,this work has presented an unsupervised image registration method using the free form deformation(FFD)and the symmetry constraint‐based generative adversarial networks(FSGAN).The FSGAN utilises the principle component analysis network‐based structural representations of the reference and float images as the inputs and uses the generator to learn the FFD model parameters,thereby producing two deformation fields.Meanwhile,the FSGAN uses two discriminators to decide whether the bilateral registration have been realised simultaneously.Besides,the symmetry constraint is utilised to construct the loss function,thereby avoiding the deformation folding.Experiments on BrainWeb,high grade gliomas,IXI and LPBA40 show that compared with state‐of‐the‐art methods,the FSGAN provides superior performance in terms of visual comparisons and such quantitative indexes as dice value,target registration error and computational efficiency. 展开更多
关键词 Free‐form deformation Generative adversarial nets Multi‐modal brain image registration Structural representation Symmetry constraint
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Situational Analysis of Malaria Control Following the 2021 Distribution of Long Lasting Insecticide-Treated Bed Nets in the Tiko Health District, South West Region, Cameroon
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作者 Jini Victor Bongajum Nyasa Raymond Babila Esum Mathias Eyong 《Journal of Biosciences and Medicines》 2023年第4期153-172,共20页
Malaria is still a major public health concern in Cameroon as more than 20 million people are at risk of the disease. Despite the government’s effort to scale up the distribution of long lasting insecticide-treated b... Malaria is still a major public health concern in Cameroon as more than 20 million people are at risk of the disease. Despite the government’s effort to scale up the distribution of long lasting insecticide-treated bed nets (LLINs), full ownership and optimal use is still limited. In 2021, over a million LLINs were made available for distribution in the South West Region. However, the current situation of malaria has not yet been ascertained following the 2021 mass distribution campaign (MDC). Therefore, the aim of this study was to determine LLIN ownership, coverage, usage and the prevalence of malaria following the 2021 MDC in the Tiko Health District (THD), South West Region of Cameroon. A cross-sectional study was carried from May 1 to 27, 2022 in which a multi-stage sampling technique was used to enroll eligible participants. Data were collected from household heads using questionnaires and capillary blood samples collected from consented household members were used to test for malaria. Data were analyzed using SPSS version 25 at 0.05 significance level. From the 150 households surveyed, 96 (64.0%) owned a mosquito net before the recent MDC. There was an overall significant increase (p p = 0.644) in LLINs ownership between areas where door-to-door (79.5%) and fixed “Hit and Run” (75.8%) strategies were used in the distribution of LLINs in THD. The prevalence of malaria was 10.2%. The regular use of LLINs was significantly associated (p = 0.007) with low malaria prevalence. The 2021 MDC had an impact on malaria prevalence in those who properly used them. 展开更多
关键词 Long Lasting Insecticide Treated-Bed Nets OWNERSHIP COVERAGE Use Malaria Prevalence
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Scale and Associated Factors of Using Pyrethroid-Impregnated Mosquito Nets as Fishing Tools on Nokoué Lake within Sô-Ava Municipality in Benin, 2020
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作者 Nicolas Ayokpon Hondo Horace Degnonvi +4 位作者 Rodrigue Landeou Franck Zinsou Mignanwande Zoulkifl Salou Bachirou Roch Christian Johnson Ghislain Emmanuel Sopoh 《Open Journal of Preventive Medicine》 2023年第6期199-212,共14页
Background: In lacustrine communities, whether in Benin or elsewhere, populations use impregnated mosquito nets (IMNs) as fishing nets. This depletes the lake of its fishery resources, which in turn are contaminated b... Background: In lacustrine communities, whether in Benin or elsewhere, populations use impregnated mosquito nets (IMNs) as fishing nets. This depletes the lake of its fishery resources, which in turn are contaminated by the pyrethroids impregnated in the nets. This study aims to determine the scale and factors associated with the use of pyrethroid-impregnated mosquito nets as fishing tools in the municipality of Sô-Ava in Benin. Methods: This is a cross-sectional and analytical study with two components. First, a quantitative component was made up of 280 volunteers who were interviewed in the seven districts of the city. Data collection was done in two phases: the first from September to October 2020, and the second in August 2022. Data were analyzed with Stata and logistic regression was used. Another qualitative component was made up of forty participants chosen by reasoned choice, of which 32 were split into four focus groups of eight members each, and the rest participated in semi-structured interviews. Triangulation of the different sources was used to analyze the data. Results: Around 67% of the population reported using impregnated mosquito nets as fishing tools and 33% exclusively for malaria. Seasonal fishermen (ORa = 2.03, CI = 1.35 - 4.97, P = 0.004) and years of professional experience (ORa = 1.53, CI = 1.00 - 2.05, P = 0.021) increase the risk of using these nets as fishing tools. The use of insecticide-treated mosquito nets against mosquitoes causes skin scratching and impairs breathing because of the impregnation products, as reported by respondents. Conclusion: A high prevalence of inappropriate use of impregnated mosquito nets in fishing practices is highlighted in this study. Interviews in the field revealed that nets are diverted for fishing purposes to increase the volume of catches. Consequently, it will be appropriate to assess the pyrethroid content in water and fishery products. 展开更多
关键词 Associated Factor Impregnated Mosquito Nets PYRETHROIDS Fishing Tools Sô-Ava
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New Superionic Memory Devices Can Provide Clues to the Human Memory Structure and to Consciousness
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作者 Hans Hermann Otto 《Journal of Applied Mathematics and Physics》 2023年第2期377-376,共10页
Since the work of Penrose and Hameroff the possibility is discussed that the location of human memory and consciousness could be connected with tubulin microtubules. If one would use superionic nano-materials rolled u... Since the work of Penrose and Hameroff the possibility is discussed that the location of human memory and consciousness could be connected with tubulin microtubules. If one would use superionic nano-materials rolled up to microtubules with an electrolyte inside the formed channels mediating fast ionic exchange of protons respectively lithium ions, it seems to be possible to write into such materials whole image arrays (pictures) under the action of the complex electromagnetic spectrum that composes these images. The same material and architecture may be recommended for super-computers. Especially microtubules with a protofilament number of 13 are the most important to note. We connected such microtubules before with Fibonacci nets composed of 13 sub-cells that were helically rolled up to deliver suitable channels. Our recent Fibonacci analysis of Wadsley-Roth shear phases such as niobium tungsten oxide , exhibiting channels for ultra-fast lithium-ion diffusion, suggests to use these materials, besides super-battery main application, in form of nanorods or microtubules as effectively working superionic memory devices for computers that work ultra-fast with the complex effectiveness of human brains. Finally, we pose the question, whether dark matter, ever connected with ultrafast movement of ordinary matter, may be responsible for synchronization between interactions of human brains and consciousness. 展开更多
关键词 Memory Device Niobium Tungsten Oxide Crystallographic Shear Lithium Intercalation Superionicity Super Battery Fibonacci Nets Fibonacci Stoichiometry Tubulin Microtubules
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中性粒细胞胞外诱捕网研究进展
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作者 彭菲 张玉明 才文明 《现代畜牧科技》 2023年第5期19-26,共8页
中性粒细胞是重要的先天免疫细胞,随着对其特殊的免疫防御机制——胞外诱捕网(NETs)研究的不断深入,有充足的证据表明NETs是一把双刃剑,当NETs适当产生时,发挥重要的免疫防御功能,诱捕甚至杀灭病原微生物;而NETs在无菌内源性物质或病原... 中性粒细胞是重要的先天免疫细胞,随着对其特殊的免疫防御机制——胞外诱捕网(NETs)研究的不断深入,有充足的证据表明NETs是一把双刃剑,当NETs适当产生时,发挥重要的免疫防御功能,诱捕甚至杀灭病原微生物;而NETs在无菌内源性物质或病原诱导条件下过量产生后,引起多种自身免疫疾病,造成机体代谢和免疫机能紊乱。最近研究发现病原逃避NETs诱捕的免疫机制,与病原本身基因进化和中性粒细胞免疫应答机能有关。该文针对NETs近年的研究进展进行总结归纳,对增强机体先天免疫机能和治疗自身免疫性疾病具有重要的临床指导意义。 展开更多
关键词 NETS 急慢性炎症 免疫逃避 系统性红斑狼疮 免疫防御
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The Evaluation of Social Sharing Nets Users’ Fundamental Principals According to Nickname Usage and Time Spent
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作者 Mehmet Ali Seven Mustafa Çağrı Engin +1 位作者 Mehmet Yıldız Ali Osman Engin 《Advances in Internet of Things》 2023年第2期31-62,共32页
This work;It was made to determine the positive and negative usage information, attitudes and behaviors of social networking networks for users. Today, it is well known how the wide social effects of social networking... This work;It was made to determine the positive and negative usage information, attitudes and behaviors of social networking networks for users. Today, it is well known how the wide social effects of social networking sites are widespread and effective. As far as it can be followed from written and visual media, it causes significant damages for attitudes and behaviors for individuals. Looking at the results of the study, it seems impossible to limit the time and necessity of these networks for people, but it is understood that people force their limits and capacity. It was determined that the general acceptance and rejection areas are mixed and the dominant distinctive effects were weakened. Unable to prevent social dissolution and deterioration was realized by these social networks of networks. However, we cannot only talk about negative effects because their positive effects should be mentioned. Data were obtained in this direction. For example, some segments encourage the users of these sites to have more freedom, to develop democracy and human rights awareness. However, the real problem is when and where to stand. This study;Social networking networks use information, attitudes and behaviors;It was carried out for the purpose of evaluating the use of nicknames and networks for the use of networks. The data of the study were obtained by the application of a questionnaire and the data obtained were analyzed with appropriate statistical analysis methods. In the first part of the study, field study/operational concept scanning is performed and theoretical information is included. In the second part, the purpose of the study, the problem status, the importance of the study, limitations, assumptions, problem question, research method, research universe and sample are specified and informed. In the third section, the data obtained using appropriate statistical methods are analyzed. In the last section, some important suggestions and comments are made in the light of the data obtained. 展开更多
关键词 Psycho-Social Effect of Facebook Facebook and Personal Harms Habitual Activity of Using Facebook Nickname Usage and Social Sharing Nets
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基于Deep Belief Nets的中文名实体关系抽取 被引量:70
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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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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:3
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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:14
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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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