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基于改进XGBoost模型的网络入侵检测研究

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计算机与现代化 2024年第6期 109-114页

作者：苏凯旋鞍钢集团信息产业有限公司辽宁鞍山114000

为了提升传统的网络入侵检测模型的检测准确性和实用性,本文提出一种基于改进梯度提升树(XGBoost)模型的网络入侵检测方法。首先,采用随机森林算法预计关键特征点,在数据的预处理阶段有效地选取了重要性权重最高的特征并构建特征集合;其... 详细信息

为了提升传统的网络入侵检测模型的检测准确性和实用性,本文提出一种基于改进梯度提升树(XGBoost)模型的网络入侵检测方法。首先,采用随机森林算法预计关键特征点,在数据的预处理阶段有效地选取了重要性权重最高的特征并构建特征集合;其次,利用卡单方程改进了XGBoost模型的预测方法;最后,在XGBoost优化算法中引入代价敏感函数来提升算法对小样本数据的检测率,应用网格法调参减少模型复杂性。实验结果表明,与其它人工智能算法对比,所提出的模型在具有更高检验精度的情况下降低了50%以上等待时间,并且在噪音环境下具有较强的可扩展性和自适应性,并结合其他模型设置参数消融实验,实验结果表明树深对模型性能影响最大。

关键词：入侵检测特征选择随机森林 XGBoost 代价敏感函数

Roles of serum uric acid on the association between arsenic exposure and incident metabolic syndrome in an older Chinese population

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Journal of Environmental Sciences 2025年第1期147卷 332-341页

作者： Haiyan Jiang Simei Zhang Yaoyao Lin Lin Meng Jiayi Li Wenqing Wang kaixuan Yang Mingjuan Jin Jianbing Wang Mengling Tang Kun Chen Department of Public Health Fourth Affiliated HospitalZhejiang University School of MedicineHangzhou 310058China Department of Public Health Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310058China Department of Public Health National Clinical Research Center for Child Health of Children’s HospitalZhejiang University School of MedicineHangzhou 310058China

Growing evidences showed that heavy metals exposure may be associated with metabolic ***,themechanism underlying arsenic(As)exposure and metabolic syndrome(MetS)risk has not been fully *** we aimed to prospectively investigate the role of serum uric acid(suA)on the association between blood As exposure and incident MetS.A sample of 1045 older participants in a community in China was *** determined As at baseline and suA concentration at follow-up in the Yiwu Elderly *** events were defined according to the criteria of the International Diabetes Federation(IDF).Generalized linear model with log-binominal regression model was applied to estimate the association of As with incident *** investigate the role of suA in the association between As andMetS,amediation analysiswas *** the fully adjusted log-binominal model,per interquartile range increment of As,the risk of MetS increased *** with the lowest quartile of As,the adjusted relative risk(RR)of MetS in the highest quartile was 1.42(95%confidence interval,CI:1.03,2.00).Additionally,blood As was positively associated with suA,while suA had significant association with MetS *** mediation analysis demonstrated that the association of As and MetS risk was mediated by suA,with the proportion of 15.7%.Our study found higher As was remarkably associated with the elevated risk of MetS in the Chinese older adults *** analysis indicated that suA might be a mediator in the association between As exposure and MetS.

关键词： Arsenic(As)exposure Metabolic syndrome(MetS) Serum uric acid(suA) Cohort study Mediation effect Older adults

Synthetic control of chiral pore surfaces in covalent organic frameworks for enantioselective separation of chiral drugs

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Science China Chemistry 2025年

作者： Shiguo Fu Xiaofeng Zhang kaixuan Wang Linfeng Chen Fan Xia Yong Cui Yan Liu School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Faculty of Materials Science and Chemistry China University of Geosciences

Enantioselective separations of racemates using porous materials are highly attractive and significant in both fundamental research and technological applications. However, achieving controlled chiral pore surfaces to create the necessary driving force for enantiomer discrimination poses a fundamental challenge. Herein, we demonstrate that chiral covalent organic frameworks(COFs) possess the essential characteristics for effective enantioseparations through synthetic control over pore surfaces. We synthesized three 3D chiral COFs (CCOFs) featuring abundant chiral recognition sites on the pore walls via the condensation of enantiopure dialdehyde of 2,2′-dihydroxy-1,1′-binaphthyl and tetraamine. All CCOFs with high stability exhibit an 11-fold interpenetrated framework with tubular open channels, decorated with dihydroxyl or diethoxyl groups. The CCOFs with dihydroxyl groups serve as solid adsorbents for the adsorptive separation and solid-phase extraction of various chiral 1-phenylethanol-derived enantiomers, particularly racemic drugs, achieving up to 98%enantiomeric excess. In contrast, the CCOF with diethoxy groups is unable to resolve the racemates. These CCOF materials can be recycled and reused without any apparent loss of performance. Density functional theory (DFT) calculations reveal that the enantiospecific recognition arises from the well-organized chiral inner sphere and multiple chiral host-guest interactions.

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矿工不安全情绪对其风险偏好的影响研究

安全与环境学报 2024年第8期24卷 3154-3164页

作者：李广利温情苏锴轩李昆泉程锦鹏张子健湖南工学院安全与管理工程学院湖南衡阳421002

为了探明矿工不安全情绪与其风险偏好的关系,基于文献研究探讨了矿工不安全情绪对其风险偏好影响的直接作用关系,自我控制的中介作用以及情绪智力和年龄的调节作用,提出了矿工不安全情绪对其风险偏好影响的理论假设。采用PROCESS插件,运... 详细信息

为了探明矿工不安全情绪与其风险偏好的关系,基于文献研究探讨了矿工不安全情绪对其风险偏好影响的直接作用关系,自我控制的中介作用以及情绪智力和年龄的调节作用,提出了矿工不安全情绪对其风险偏好影响的理论假设。采用PROCESS插件,运用Bootstrap方法检验回归系数的显著性,以验证理论假设的合理性。结果显示:矿工不安全情绪显著正向影响其风险偏好水平;自我控制在矿工不安全情绪影响其风险偏好过程中具有部分中介效应;情绪智力在矿工不安全情绪影响其自我控制过程中具有调节作用:高情绪智力水平的矿工,在弱化其不安全情绪对自我控制的负向影响中更加有效;矿工年龄可调节其不安全情绪对风险偏好影响的直接过程,但仅在30~39岁及40~49岁年龄组具有调节效应,随着年龄的增长,矿工不安全情绪对其风险偏好的正向影响逐渐减弱。研究结果为降低矿工风险偏好水平,提升矿工安全行为决策能力提供了实证依据。

关键词：安全人体学矿工不安全情绪风险偏好情绪智力自我控制

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IP承载网稳定性提升技术研究

移动信息 2016年第6期 15-16页

作者：刘博蕙彭嘉填苏凯旋中国移动通信广东有限公司汕头分公司广东汕头515000

IP承载网是一种比较新型的技术,可以同时支持企业互联、数据、音频等多种业务,一般被用于服务高要求、高价值的电信业务。为提高其应用效率,需要从技术角度分析,采取合理的措施,不断提高其稳定性。对IP承载网进行了分析,并提出了相应的... 详细信息

IP承载网是一种比较新型的技术,可以同时支持企业互联、数据、音频等多种业务,一般被用于服务高要求、高价值的电信业务。为提高其应用效率,需要从技术角度分析,采取合理的措施,不断提高其稳定性。对IP承载网进行了分析,并提出了相应的稳定性提升技术。

关键词： IP承载网稳定性下一代网络

Development of a fast LC-QqQ-MS/MS method for detecting flavonoids in the phenylpropanoid pathway of plants

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Journal of Integrative Agriculture 2025年第1期24卷 398-402页

作者： Dili Lai Yu Fan Md.Nurul Huda Yuanfen Gao Tanzim Jahan Wei Li Yuqi He kaixuan Zhang Jianping Cheng Jingjun Ruan Baoping Zhao Meiliang Zhou State Key Laboratory of Crop Gene Resources and Breeding/Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China College of Agriculture Guizhou UniversityGuiyang 550025China School of Food and Biological Engineering Chengdu UniversityChengdu 610106China Agronomy College Inner Mongolia Agricultural UniversityHohhot 010019China

The phenylpropane metabolic pathway is one of the most significant metabolic pathways in plants,synthesizing more than 8,000 metabolites,including flavonoids,lignans,lignin,coumarins,and other metabolites through multiple branching pathways(Zhang and Liu 2015;Gao et al.2024).This pathway is crucial in plant growth,development,and plant-environment interactions(Dong and Lin 2021).

关键词： MS/MS branching

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： kaixuan Zhou Gaoxiong Duan Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun Liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

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“冷盆”缫丝技术与阆中源考

丝绸 2025年第1期62卷 94-100页

作者：刘凯旋陈祥平程明四川省丝绸科学研究院成都610031 四川省丝绸协会成都610031

四川省阆中市出土的“缫丝图铜摆件”被专家鉴定为宋代铸造,其展现的煮、缫分离的“冷盆”缫丝技术,乃现代缫丝工业技术之雏形,对于蚕丝品质的提升具有里程碑的意义。而现已出版的中国丝绸史书籍中将“冷盆”缫丝技术划归元代加以描述... 详细信息

四川省阆中市出土的“缫丝图铜摆件”被专家鉴定为宋代铸造,其展现的煮、缫分离的“冷盆”缫丝技术,乃现代缫丝工业技术之雏形,对于蚕丝品质的提升具有里程碑的意义。而现已出版的中国丝绸史书籍中将“冷盆”缫丝技术划归元代加以描述。文章对宋代前后缫车及缫丝工艺技术演变过程进行历史追溯和研究,对阆中从宋代至民国与“冷盆”缫丝相关的历史脉络进行梳理,以探究“冷盆”缫丝技术的渊源。研究表明,“冷盆”缫丝技术源于宋代,而“缫丝图铜摆件”所呈现的煮、缫分离的缫丝生产场景,与现有文献典籍及图考中所载“冷盆”缫丝高度契合,且三者互为映射,从而印证了阆中(古阆州)为宋代“冷盆”缫丝技术源流地。

关键词：宋代缫丝图铜摆件缫丝技术阆中冷盆缫丝源流地

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斑岩系统中低熔点亲铜元素与稀贵金属赋存状态和富集机制研究:以藏东南普朗超大型斑岩Cu-Au矿床为例

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岩石学报 2025年第2期41卷 621-641页

作者：王大钊梁丰王艳军李凯旋刘家军冷成彪东华理工大学铀资源探采与核遥感全国重点实验室南昌330013 东华理工大学核资源与环境国家重点实验室南昌330013 中国地质大学地质过程与矿产资源国家重点实验室北京100083 中国地质大学(北京)地球科学与资源学院北京100083

斑岩铜矿床常伴生大量低熔点亲铜元素(LMCE,包括Te、Se、Bi、Sb、As等)和稀贵金属(NM,包括Au、Ag、PGE),但这些元素的相互作用关系、富集分异机制及其控制因素尚不清楚。普朗斑岩Cu-Au矿床是位于特提斯-喜马拉雅成矿带中的超大型矿床,... 详细信息

斑岩铜矿床常伴生大量低熔点亲铜元素(LMCE,包括Te、Se、Bi、Sb、As等)和稀贵金属(NM,包括Au、Ag、PGE),但这些元素的相互作用关系、富集分异机制及其控制因素尚不清楚。普朗斑岩Cu-Au矿床是位于特提斯-喜马拉雅成矿带中的超大型矿床,矿床中富集伴生元素,具有重要的经济价值,成为探讨这些问题的理想研究对象。本文利用扫描电镜、电子探针及硫化物LA-ICP-MS等原位分析技术对普朗矿床中伴生元素的分布规律、赋存状态及形成过程开展研究。结果表明,LMCE和NM主要以微粒包体形式赋存于硫化物中,并形成富硒方铅矿、辉碲铋矿、辉铋矿、辉硒铋矿、硫银铋矿、银金矿/金银矿、硒银矿、碲银矿、碲钯矿、碲铂矿、砷碲钯矿和富钯辉钴矿等矿物。普朗矿床中的铂族元素矿物(PGM)至少存在早期高温、晚期低温两个阶段的结晶,其中自形粒状的碲钯矿和碲铂矿结晶温度高、结晶空间开阔,可能是高温下直接由LMCE-Pt-Pd熔体固结形成,PGM形成后继续在流体中迁移并被后期结晶的硫化物捕获;而碲银矿±砷锑钯矿±辉碲铋矿±辉铋矿矿物组合具有固溶体分解和二面角等典型的熔体固结结构,推测为低温下NM-LMCE熔体充填在已结晶的硫化物裂隙和孔洞中形成。斑岩铜矿床从岩浆形成到热液出溶再到矿质沉淀的全过程均伴随着LMCE和NM的分异和富集,其中LMCE熔体对NM的高效富集具有重要意义。

关键词：斑岩铜矿低熔点亲铜元素铂族元素富集分异机制普朗