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基于FP-Growth算法和贝叶斯模型的坍塌事故致因分析
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作者 李珏 曾敏 《武汉理工大学学报(信息与管理工程版)》 2026年第1期15-21,共7页
为探究建筑施工安全风险,深入分析建筑工程中的坍塌事故风险,通过改进的人因分析和分类系统(HFACS)模型识别出32个坍塌事故的关键致因。同时为深入挖掘事故特征,明确施工坍塌事故的成因机制,采用基于FP-Growth算法的关联规则挖掘方法构... 为探究建筑施工安全风险,深入分析建筑工程中的坍塌事故风险,通过改进的人因分析和分类系统(HFACS)模型识别出32个坍塌事故的关键致因。同时为深入挖掘事故特征,明确施工坍塌事故的成因机制,采用基于FP-Growth算法的关联规则挖掘方法构建贝叶斯网络结构,通过数据驱动的方式训练模型,从而提升坍塌事故推理分析的效率与精度。基于贝叶斯网络的敏感性分析与逆向推理,识别出5类坍塌事故的关键致因及其致因路径。研究结果表明:土方坍塌、建筑物坍塌、拆除工程坍塌和模板坍塌多由不安全行为前提条件造成,脚手架坍塌多由不安全行为前提条件和不安全行为共同造成。通过关键致因链分析可知5类坍塌事故的发生路径,从而对各类事故进行管控。 展开更多
关键词 FP-growth算法 贝叶斯网络 HFACS模型 风险分析 关联规则
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基于FP-growth算法与贝叶斯网络的冲击地压事故致因分析
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作者 欧阳振华 肖曼曼 +2 位作者 刘建 许乾海 鞠成润 《华北科技学院学报》 2026年第1期106-116,共11页
为克服传统方法在分析冲击地压多因素耦合致灾方面的不足,精准解析该灾害的致因逻辑并实现风险前置管控,本文以2001-2024年间56份权威事故调查报告为样本,利用FP-growth算法对非结构化文本进行挖掘,通过支持度-置信度-提升度三维过滤机... 为克服传统方法在分析冲击地压多因素耦合致灾方面的不足,精准解析该灾害的致因逻辑并实现风险前置管控,本文以2001-2024年间56份权威事故调查报告为样本,利用FP-growth算法对非结构化文本进行挖掘,通过支持度-置信度-提升度三维过滤机制提取高频共现致因;继而融合挖掘结果与领域知识,构建具备先验-后验动态更新能力的贝叶斯网络拓扑,实现致因链的概率推理与风险反演。揭示了“地质-开采-管理”因素耦合的非线性致灾规律,定量识别出煤岩冲击倾向性、地质构造、开采深度等地质因素的主导作用,以及采掘扰动、煤柱等开采因素的关键触发效应,同时明确了安全意识不足等管理因素的风险放大作用。基于量化分析结果,提出了针对性的冲击地压风险前置管控措施,为煤矿企业优化开采方案与精准部署卸压监测工程提供了科学依据,可推动冲击地压防治由经验驱动向数据-知识协同驱动转型。 展开更多
关键词 冲击地压 致灾因素 FP-growth算法 贝叶斯网络 关联关系
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The Quantitative Law of Network Information Growth 被引量:1
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作者 Jingehuan Hou Tingxiao Wen Junping Qiu 《Chinese Business Review》 2004年第2期10-19,共10页
Based on the assumptions of "information transfer" and "information creation", this paper educes the multiplied growth mechanism of network information: that the gross quantity of network information (Im) is ab... Based on the assumptions of "information transfer" and "information creation", this paper educes the multiplied growth mechanism of network information: that the gross quantity of network information (Im) is about n times as much as the quantity of real network information (Ir). According to this theoretical model, we give a uniform explanation to all kinds of information growth models in existence, and put forward some proposals, such as "forbidding information transfer" and "building up the central information base", to control the repeated information flooding on the network and facilitate the full use of network information. 展开更多
关键词 webmetrics law of network information growth network information multiplier Internet economy central information base
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An evolving network model with modular growth 被引量:1
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作者 Zou Zhi-Yun Liu Peng +1 位作者 Lei Li Gao Jian-Zhi 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期603-609,共7页
In this paper, we propose an evolving network model growing fast in units of module, according to the analysis of the evolution characteristics in real complex networks. Each module is a small-world network containing... In this paper, we propose an evolving network model growing fast in units of module, according to the analysis of the evolution characteristics in real complex networks. Each module is a small-world network containing several interconnected nodes and the nodes between the modules are linked by preferential attachment on degree of nodes. We study the modularity measure of the proposed model, which can be adjusted by changing the ratio of the number of inner- module edges and the number of inter-module edges. In view of the mean-field theory, we develop an analytical function of the degree distribution, which is verified by a numerical example and indicates that the degree distribution shows characteristics of the small-world network and the scale-free network distinctly at different segments. The clustering coefficient and the average path length of the network are simulated numerically, indicating that the network shows the small-world property and is affected little by the randomness of the new module. 展开更多
关键词 EVOLVING modular growth small-world network scale-free network
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Discrete Choice Analysis of Temporal Factors on Social Network Growth
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作者 Kwok-Wai Cheung Yuk Tai Siu 《Intelligent Information Management》 2024年第1期21-34,共14页
Social networks like Facebook, X (Twitter), and LinkedIn provide an interaction and communication environment for users to generate and share content, allowing for the observation of social behaviours in the digital w... Social networks like Facebook, X (Twitter), and LinkedIn provide an interaction and communication environment for users to generate and share content, allowing for the observation of social behaviours in the digital world. These networks can be viewed as a collection of nodes and edges, where users and their interactions are represented as nodes and the connections between them as edges. Understanding the factors that contribute to the formation of these edges is important for studying network structure and processes. This knowledge can be applied to various areas such as identifying communities, recommending friends, and targeting online advertisements. Several factors, including node popularity and friends-of-friends relationships, influence edge formation and network growth. This research focuses on the temporal activity of nodes and its impact on edge formation. Specifically, the study examines how the minimum age of friends-of-friends edges and the average age of all edges connected to potential target nodes influence the formation of network edges. Discrete choice analysis is used to analyse the combined effect of these temporal factors and other well-known attributes like node degree (i.e., the number of connections a node has) and network distance between nodes. The findings reveal that temporal properties have a similar impact as network proximity in predicting the creation of links. By incorporating temporal features into the models, the accuracy of link prediction can be further improved. 展开更多
关键词 Discrete Choice Models Temporal Factors Social network Link Prediction network growth
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Hybrid Reliability Parameter Selection Method Based on Text Mining, Frequent Pattern Growth Algorithm and Fuzzy Bayesian Network 被引量:1
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作者 SHUAI Yon SONG Tailian +1 位作者 WANG Jianping ZHAN Wenbin 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第3期423-428,共6页
Reliability parameter selection is very important in the period of equipment project design and demonstration. In this paper, the problem in selecting the reliability parameters and their number is proposed. In order ... Reliability parameter selection is very important in the period of equipment project design and demonstration. In this paper, the problem in selecting the reliability parameters and their number is proposed. In order to solve this problem, the thought of text mining is used to extract the feature and curtail feature sets from text data firstly, and frequent pattern tree (FPT) of the text data is constructed to reason frequent item-set between the key factors by frequent patter growth (FPC) algorithm. Then on the basis of fuzzy Bayesian network (FBN) and sample distribution, this paper fuzzifies the key attributes, which forms associated relationship in frequent item-sets and their main parameters, eliminates the subjective influence factors and obtains condition mutual information and maximum weight directed tree among all the attribute variables. Furthermore, the hybrid model is established by reason fuzzy prior probability and contingent probability and concluding parameter learning method. Finally, the example indicates the model is believable and effective. 展开更多
关键词 reliability parameter text mining frequent pattern growth(FPG) fuzzy Bayesian network(FBN)
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Market presence in China Strengthened Network Growth and Dual-Chinese-Hub Strategy
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作者 Audrey Guo 《China's Foreign Trade》 2008年第2期52-,共1页
  In the end of 2007, Air China Limited (hereinafter "Air China") and Shanghai Airlines, formally joined Star Alliance at a ceremony held in the new Terminal Three at Beijing Capital International Airport....   In the end of 2007, Air China Limited (hereinafter "Air China") and Shanghai Airlines, formally joined Star Alliance at a ceremony held in the new Terminal Three at Beijing Capital International Airport. With the addition of the two Chinese airlines, Star Alliance now has 19 member carriers operating 17,000 daily flights to 897 destinations in 160 countries.…… 展开更多
关键词 Star Market presence in China Strengthened network growth and Dual-Chinese-Hub Strategy
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ZTE Achieves Strong Growth of Bearer Network Products
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《ZTE Communications》 2008年第3期33-33,共1页
ZTE Corporation continues to register remarkable growthrate for its bearer network products according to theannouncement the
关键词 ZTE Achieves Strong growth of Bearer network Products
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ZTE Records Highest Industry Growth for Optical Networking Solutions
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《ZTE Communications》 2008年第3期19-19,共1页
ZTE Corporation has the highest industry sales growth in the area of Optical Networking (ON)last year,according tothe report published by
关键词 ZTE Records Highest Industry growth for Optical networking Solutions
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User growth and penetration modeling for converged heterogeneous network 被引量:1
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作者 SADIA Murawwat 赵三元 +4 位作者 岳雷 张超 薛丞博 MUHAMMAD Imran Malik 沈庭芝 《Journal of Beijing Institute of Technology》 EI CAS 2013年第3期361-366,共6页
To evaluate the trail potential of converged heterogeneous network (CHN) market, the logistic method for adoption modeling of CHN is used. User growth & penetration have been taken as two variants to find saturatio... To evaluate the trail potential of converged heterogeneous network (CHN) market, the logistic method for adoption modeling of CHN is used. User growth & penetration have been taken as two variants to find saturation condition in market. Model is continuous in time but modifications are done for discrete recurrence equation, commonly known as logistic map. Dynamic and static phases are taken into consideration while penetration decay is not covered in this model. 展开更多
关键词 CONVERGENCE heterogeneous network logistic model user growth user penetration
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Urban Growth Modeling Using Neural Network Simulation: A Case Study of Dongguan City, China
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作者 Xinmin Zhang 《Journal of Geographic Information System》 2016年第3期317-328,共12页
Dongguan is an important industrial city, located in the Pearl River Delta, South China. Recently, Dongguan city experienced a rapid urban growth with the locational advantage by transforming from traditional agricult... Dongguan is an important industrial city, located in the Pearl River Delta, South China. Recently, Dongguan city experienced a rapid urban growth with the locational advantage by transforming from traditional agricultural region to modern manufacturing metropolis. The urban transformation became the usual change in China under the background of urbanization which belongs to one trend of globalization in the 21st century. This paper tries to analyze urban growth simulation based on remotely sensed data of previous years and the related physical and socio-economic factors and predict future urban growth in 2024. The study examined and compared the land use/cover (LUC) changes over time based on produced maps of 2004, 2009, and 2014. The results showed that water and forest area decreased since the past years. In contrast, the urban land increased from 2004 to 2014, and this increasing trend will continue to the future years through the urbanization process. Having understood the spatiotemporal trends of urban growth, the study simulated the urban growth of Dongguan city for 2024 using neural network simulation technique. Further, the figure of merit (FoM) of simulated map of 2014 map was 8.86%, which can be accepted in the simulation and used in the prediction process. Based on the consideration of water body and forest, the newly growth area is located in the west, northeast, and southeast regions of Dongguan city. The finding can help us to understand which areas are going to be considered in the future urban planning and policy by the local government. 展开更多
关键词 Urban growth Neural network Simulation Dongguan City
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Using Artificial Neural-Networks in Stochastic Differential Equations Based Software Reliability Growth Modeling
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作者 Sunil Kumar Khatri Prakriti Trivedi +1 位作者 Shiv Kant Nisha Dembla 《Journal of Software Engineering and Applications》 2011年第10期596-601,共6页
Due to high cost of fixing failures, safety concerns, and legal liabilities, organizations need to produce software that is highly reliable. Software reliability growth models have been developed by software developer... Due to high cost of fixing failures, safety concerns, and legal liabilities, organizations need to produce software that is highly reliable. Software reliability growth models have been developed by software developers in tracking and measuring the growth of reliability. Most of the Software Reliability Growth Models, which have been proposed, treat the event of software fault detection in the testing and operational phase as a counting process. Moreover, if the size of software system is large, the number of software faults detected during the testing phase becomes large, and the change of the number of faults which are detected and removed through debugging activities becomes sufficiently small compared with the initial fault content at the beginning of the testing phase. Therefore in such a situation, we can model the software fault detection process as a stochastic process with a continuous state space. Recently, Artificial Neural Networks (ANN) have been applied in software reliability growth prediction. In this paper, we propose an ANN based software reliability growth model based on Ito type of stochastic differential equation. The model has been validated, evaluated and compared with other existing NHPP model by applying it on actual failure/fault removal data sets cited from real software development projects. The proposed model integrated with the concept of stochastic differential equation performs comparatively better than the existing NHPP based model. 展开更多
关键词 Software Reliability growth Model Artificial NEURAL network STOCHASTIC DIFFERENTIAL EQUATION (SDE) STOCHASTIC Process
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URBAN GROWTH, TRANSPORTATION SYSTEM AND COMMERCIALNETWORK OF BEIJING
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作者 Yang Wuyang(Department of Geography, Peking University, Beijing 100871)People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1995年第3期15-31,共17页
In this afticle, three uopt problems on the developlnent and plabong of Beijing metropolis are expounded (1) Having analyzed the process of urbanlzation dunng 45 years, the autihor divides it into three Stages :city e... In this afticle, three uopt problems on the developlnent and plabong of Beijing metropolis are expounded (1) Having analyzed the process of urbanlzation dunng 45 years, the autihor divides it into three Stages :city expansion, qrban sprawl and fonmation of centnpotal urban nngr. Then a rank-number-size law is pLif fotward to predict the development and allocation of satellite towns (2) Having looked back on the change of urban transpoftation nforork, the atlthor points out its merits and demerits.According to the increases of traffic flow, improving measures for the urban road systems are demonstrated. (3) Having reviewed the llistory of commercial distnbution and referred to previous lnodels, the author roprds the spatial structure of business as a combined network from central place and idealized stnucture of lnetropolitan area. The trade and service orgaluzation in n1ain urban area and peripheral zone can be planned with defferent ways. The atlthor predicts a rational network of commerce and service of Beijing with a strong BCD Which is accepted by some trade authorities 展开更多
关键词 urban growth central place theory transportation system commercial network
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从知识涌现到扩散:“新”—“兴”主题成长特征动态测度研究
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作者 赵又霖 王月妹 +2 位作者 王嘉杰 封丽 石燕青 《图书情报工作》 北大核心 2026年第7期83-100,共18页
[目的/意义]在新兴主题成长过程中,主题涌现时的知识创新程度体现为“新”的特质,而主题扩散下的知识传播潜力则展现为“兴”的趋势。为解决当前测度方法中对主题创新来源探究不足以及跨领域扩散潜力动态反映缺失的问题,通过优化测度维... [目的/意义]在新兴主题成长过程中,主题涌现时的知识创新程度体现为“新”的特质,而主题扩散下的知识传播潜力则展现为“兴”的趋势。为解决当前测度方法中对主题创新来源探究不足以及跨领域扩散潜力动态反映缺失的问题,通过优化测度维度和指标框架,提升测度结果的准确度与时效性。[方法/过程]从主题形成机制出发,贯穿知识涌现到扩散全貌,构建融合知识涌现创新性和知识扩散传播潜力维度的成长特征动态测度指标框架KEDT-GFDIM。在知识涌现创新性维度,基于主题关联网络分析新主题演化路径,结合时间、语义与路径结构差异计算主题创新性;在知识扩散传播潜力维度,基于主题扩散网络反映主题传播能力,通过引文关系引入IPC跨领域流动量化主题扩散潜力。[结果/结论]在定量评估上,KEDT-GFDIM测度方法与传统测度方法相比,识别准确度提升了16.7%,且识别时效性得到提高,可更敏锐地检测到新兴主题或主题未来的发展趋势;在定性分析上,对动态成长曲线及国家相关政策进行分析可知,所识别出的三大新兴主题与其相一致,证明构建的动态测度方法能有效识别领域新兴主题。 展开更多
关键词 新兴主题 知识涌现 知识扩散 复杂网络 成长特征测度
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人工智能企业创新网络成长机制研究——基于新闻文本挖掘的指数随机图模型分析
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作者 杨伟 沈薇 李玲菲 《研究与发展管理》 北大核心 2026年第1期39-51,共13页
深入理解创新网络成长机制是企业开展合作创新和构筑创新生态系统的关键。以“AI四小龙”为实证对象,基于新闻文本挖掘数据和专利数据构建其创新网络,借助指数随机图模型研究内生和外生变量对网络成长的影响。研究结果表明:“AI四小龙... 深入理解创新网络成长机制是企业开展合作创新和构筑创新生态系统的关键。以“AI四小龙”为实证对象,基于新闻文本挖掘数据和专利数据构建其创新网络,借助指数随机图模型研究内生和外生变量对网络成长的影响。研究结果表明:“AI四小龙”企业创新网络具有小世界网络的特征,网络呈现明显的“中心—边缘”分布;内生结构效应对各人工智能企业创新网络成长的影响基本一致,其中闭合三角形结构是持续推动人工智能企业创新网络成长的重要内生动力,开放三角结构在企业创新网络成长初期作用不显著,但到快速扩张和稳定发展阶段起正向驱动作用,而星型结构会抑制网络的形成和成长;节点属性效应对4个企业创新网络呈异质性影响,“AI四小龙”在不同阶段与企业、学研机构和政府的合作侧重有所不同,呈现出“研发驱动—政企协同”“企业联动—政企协同”和“政府扶持—研发深化”3种合作伙伴驱动模式;从外生网络效应来看,地理邻近性对人工智能企业创新网络的影响不明显。研究结论不仅为创新网络成长机制提供新的理论依据,也为同类研究提供了新的数据来源。 展开更多
关键词 人工智能 创新网络 ERGM 成长机制
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基于改进苔藓生长优化算法的矿井通风网络解算收敛性研究
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作者 杨培尧 聂兴信 +2 位作者 张鑫 赵林海 苟晓斌 《黄金》 2026年第1期28-35,共8页
为应对地下矿井工作面用风需求,提出一种分支风量自适应调控方法。依据矿井通风三大基本定律建立地下通风网络数学模型,确定以最小风机功率为目标函数建立非线性规划模型,并利用罚函数法去约束化。通过风网灵敏度的相关知识确定最优可... 为应对地下矿井工作面用风需求,提出一种分支风量自适应调控方法。依据矿井通风三大基本定律建立地下通风网络数学模型,确定以最小风机功率为目标函数建立非线性规划模型,并利用罚函数法去约束化。通过风网灵敏度的相关知识确定最优可调分支集并确定风量调节范围,引入苔藓生长优化算法对风量寻优流程进行优化,并通过性能对比分析验证了该算法通风网络解算的收敛性能。基于矿井风量智能调控试验平台,对灵敏分支风量调控方案进行试验验证。设计了系统的总体结构,开发了相关的功能模块,调用IMGO对目标风量进行寻优,输出最优的调风方案与具体的调风参数,验证了基于灵敏分支风量调控方案的可行性与有效性。结果显示,利用IMGO算法求得的最优风机功率为240.56 kW,平均风机风压为2588.53 Pa,平均迭代次数为270次,平均迭代时间为20.5 s,各项数据均明显优于其他两种优化算法。因此,改进后的苔藓生长优化算法在寻优性能和稳定性方面均有较大提升,能够提高地下通风网络解算的效率。研究结果为矿井通风网络的优化提供参考。 展开更多
关键词 矿井通风 通风网络 苔藓生长算法 收敛性 风网解算
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间充质干细胞来源细胞外囊泡干预细胞调控网络治疗肺纤维化的机制与临床策略
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作者 丁炎 聂宏光 孙宇 《中国组织工程研究》 北大核心 2026年第19期5024-5032,共9页
背景:肺纤维化是一种以细胞外基质异常沉积为特征的慢性进行性肺疾病,目前缺乏有效的治疗手段。间充质干细胞来源细胞外囊泡凭借脂质包膜结构可穿越体内屏障,将多种抗纤维化、免疫调节因子(如生长因子、免疫调节细胞因子、趋化因子)、... 背景:肺纤维化是一种以细胞外基质异常沉积为特征的慢性进行性肺疾病,目前缺乏有效的治疗手段。间充质干细胞来源细胞外囊泡凭借脂质包膜结构可穿越体内屏障,将多种抗纤维化、免疫调节因子(如生长因子、免疫调节细胞因子、趋化因子)、脂质和核酸(mRNA和miRNA)等生物活性物质直接递送至肺内靶细胞。目的:系统综述间充质干细胞来源细胞外囊泡治疗肺纤维化的核心机制,总结和阐述间充质干细胞来源细胞外囊泡将携带的生物活性物质直接递送至肺内不同靶细胞,展现出调控肺纤维化微环境的独特优势,为将来利用间充质干细胞来源细胞外囊泡治疗肺纤维化疾病提供理论基础。方法:应用计算机检索中国知网、Pub Med数据库、clinicaltrials.gov数据库和中国临床试验注册中心,英文检索关键词为“Mesenchymal stem cells,Extracellular vesicles,Pulmonary fibrosis,Alveolar epithelium,Microvascular endothelium,Macrophages,Neutrophils”,中文检索关键词为“间充质干细胞,细胞外囊泡,肺纤维化,上皮细胞,血管内皮细胞,巨噬细胞,中性粒细胞”,最终纳入56篇文献进行总结。结果与结论:在肺泡上皮细胞中,通过调控蛋白激酶B/糖原合成酶激酶3β、转化生长因子β/Smad等信号通路抑制上皮间质转化进程,以及特定miRNA(如miR-466f-3p、let-7等)阻断促纤维化通路网络。而在成纤维细胞和内皮细胞中,分别通过miR-21-5p和miR-218/miR-214-3p干预成纤维细胞的活化和内皮间质转化,同时从宏观上重编程单核细胞、调控巨噬细胞极化、抑制树突细胞成熟及平衡Th17/Treg反应,重塑免疫微环境。此外,基于工程化修饰(靶向肽修饰、药物共载)的间充质干细胞来源细胞外囊泡还可增强病变区域多细胞亚型的精准靶向性,而囊泡异质性、规模化制备标准及体内动态示踪技术仍是临床转化的关键瓶颈。未来研究需结合单细胞测序与空间多组学技术,深入解析间充质干细胞来源细胞外囊泡干预细胞调控网络的深入机制,制定以细胞为靶点的新型肺纤维化临床治疗策略。 展开更多
关键词 肺纤维化 细胞外囊泡 细胞调控网络 生长因子 上皮间质转化
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基于非线性自回归神经网络构建肉葡萄球菌生长动力学模型及其冻干损伤研究
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作者 王仪 祝超智 +5 位作者 郑飏衣 丁科慧 白雪原 崔文明 王闯 赵改名 《食品与发酵工业》 北大核心 2026年第4期174-181,共8页
肉葡萄球菌应用于肉制品发酵中可有效改善产品风味与色泽。为制备高活性发酵剂,该研究通过单因素试验优化肉葡萄球菌的培养条件和发酵罐工艺,提高活菌数,并以非线性自回归(nonlinear autoregressive,NAR)神经网络构建菌体生长动力学模... 肉葡萄球菌应用于肉制品发酵中可有效改善产品风味与色泽。为制备高活性发酵剂,该研究通过单因素试验优化肉葡萄球菌的培养条件和发酵罐工艺,提高活菌数,并以非线性自回归(nonlinear autoregressive,NAR)神经网络构建菌体生长动力学模型。进一步利用真空冷冻干燥技术制备发酵剂,通过单因素试验确定菌株的最适预冻温度。为评估菌株的冻干损伤,通过测定细胞膜完整性、流动性及Na^(+)/K^(+)-ATP酶活性变化,并结合扫描电镜观察菌体三维立体结构,以此为依据采用相应的冻干保护剂来降低损伤。结果表明,最佳的培养条件为:接种量1%(体积分数),初始pH值为7.5,温度35~40℃,此时的活菌数为2.53×10^(9)CFU/mL;发酵罐的最佳工艺条件为:转速400 r/min,以氨水为中和剂维持发酵罐内pH值为7.5,活菌数可达7.56×10^(10)CFU/mL,是优化前的40倍。NAR神经网络所构建的菌体生长动力学模型可较精确地预测菌体增殖趋势。此外,单因素试验表明,-80℃下冻干存活率为19.9%,Na^(+)/K^(+)-ATP酶活性降低77%。激光共聚焦与荧光偏振结果表明,细胞膜的完整性、流动性受到较大损伤,扫描电镜下菌体的三维立体结构遭到破坏。明确冻干损伤后,初步分析可能采用的冻干保护剂为脱脂乳、海藻糖、甘露醇。综上,该研究实现了肉葡萄球菌的高密度培养,为提高肉葡萄球菌冻干存活率提供参考,为下一步发酵剂的制备奠定了理论基础。 展开更多
关键词 肉葡萄球菌 高密度培养 NAR神经网络 菌体生长动力学模型 冻干损伤
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基于FP-Growth算法和GRNN的电力知识文本挖掘 被引量:11
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作者 白勇 张占龙 熊隽迪 《计算机科学》 CSCD 北大核心 2021年第8期86-90,共5页
为了提高电力知识文本挖掘的性能,采用FP-Growth算法对影响电力需求的强关联因素进行挖掘,运用广义回归神经网络(General Regression Neural Network,GRNN)算法实现电力需求预测。首先,对待挖掘的电力文本进行指标提取并编码,生成电力... 为了提高电力知识文本挖掘的性能,采用FP-Growth算法对影响电力需求的强关联因素进行挖掘,运用广义回归神经网络(General Regression Neural Network,GRNN)算法实现电力需求预测。首先,对待挖掘的电力文本进行指标提取并编码,生成电力文本初始FP-Tree;接着采用FP-Growth算法遍历所有FP-Tree,生成频繁集,过滤掉小于最小支持度的项,留下频数较高的频繁项;然后根据更新后的FP-Tree统计关联项,选择与总用电量增长率关联强的变量生成训练样本;最后采用GRNN算法对电力需求文本进行训练,输入电力需求预测样本,设置平滑因子,通过模式层的输出和加权求和来获得电力需求预测结果。实验结果证明,通过合理设置最小支持度和GRNN的平滑因子,能够获得较好的电力文本挖掘性能,与常用挖掘算法相比,所提算法能够获得更高的电力需求预测准确率。 展开更多
关键词 电力文本挖掘 FP-growth算法 广义回归神经网络 平滑因子 频繁集
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植物碳酸酐酶的功能及调控
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作者 张文松 陈杰 +3 位作者 张楚涵 殷国梅 王国良 产祝龙 《植物生理学报》 北大核心 2026年第2期153-161,共9页
碳酸酐酶(CA)是一类广泛存在于植物中的含锌金属酶,其核心功能是催化CO_(2)与HCO_(3)^(-)的可逆转化。本文综述了碳酸酐酶在植物光合作用、生长发育及逆境响应中的作用,同时也总结了碳酸酐酶基因表达的调控网络,并展望了未来研究方向,... 碳酸酐酶(CA)是一类广泛存在于植物中的含锌金属酶,其核心功能是催化CO_(2)与HCO_(3)^(-)的可逆转化。本文综述了碳酸酐酶在植物光合作用、生长发育及逆境响应中的作用,同时也总结了碳酸酐酶基因表达的调控网络,并展望了未来研究方向,以期为解析植物碳酸酐酶系统功能及调控网络奠定理论基础,并为通过基因工程提高作物产量和增强抗逆性提供理论参考。 展开更多
关键词 碳酸酐酶 基因功能 光合作用 生长发育 逆境 调控网络
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