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Chinese Chemical Letters 2023年第3期34卷 442-446页

作者： Wenyi Bian xueli shen Huang Tan Xing Fan Yunxia Liu Haiping Lin Youyong Li Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710062China Macao Institute of Materials Science and Engineering Macao University of Science and TechnologyMacaoChina

The on-purpose direct propane dehydrogenation(PDH) has received extensive attention to meet the everincreasing demand of *** this work,by means of density functional theory(DFT) calculations,we systematically studied the intrinsic coordinating effect of Fe single-atom catalysts in ***,the N and P dual-coordinated single Fe(Fe-N_(3)P-C) significantly outperform the Fe-N_(4-)C site in catalysis and exhibit desired activity and selectivity at industrial PDH *** mechanistic origin of different performance on Fe-N_(3)P-C and Fe-N_(4-)C has been ascribed to the geometric *** be specific,the in-plane configuration of Fe-N_(4) site exhibits low H affinity,which results in poor activity in C-H bond *** contrast,the out-of-plane structure of Fe-N_(3)P-C site exhibits moderate H affinity,which not only promote the C-H bond scission but also offer a platform for obtaining appropriate H diffusion rate which ensures the high selectivity of propylene and the regeneration of *** work demonstrates promising applications of dual-coordinated single-atom catalysts for highly selective propane dehydrogenation.

关键词： Non-oxidative propane dehydrogenation Propylene selectivity Single-atom catalysis Heteroatom-doped graphene Fe catalyst

Heat rate variability and dyssomnia and their correlations to neurological defects in cerebral infarction patients complicated by insomnia A concurrent non-randomized case-control study

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Neural Regeneration Research 2008年第1期3卷 66-70页

作者： Jianping Chu xueli shen Jun Fan Changhai Chen Shuyang Lin The 202 Hospital of Chinese PLA Shenyang 110003 Liaoning Province China Department of Neurology First Hospital Affiliated to China Medical University Shenyang 110000 Liaoning Province China

BACKGROUND： Heart rate variability refers to the beat-to-beat alteration in heart rate. It is usually a slight periodic variation of R-R intervals. Much information of autonomic nerve system balance can be obtained by measuring the heart rate variability of patients. It remains to be shown whether heart rate variability can be used as an index for determining the severity of insomnia and cerebral infarction. OBJECTIVE： This study aimed to analyze the correlation for each frequency spectrum parameter of heart rate variability with an insomnia index, as well as the degree of neurological defects in patients with simple cerebral infarction and cerebral infarction complicated by insomnia. The goal was to verify the feasibility of frequency spectrum parameters for heart rate variability as a marker for insomnia and cerebral infarction. DESIGN： A case-control observation. SETTING： Department of Neurology, First Hospital Affiliated to China Medical University. PARTICIPANTS： Sixty inpatients, and/or outpatients, with cerebral infarction were admitted to the 202 Hospital of Chinese PLA between December 2005 and October 2006, confirmed by CT, and recruited to the study. According to the insomnia condition （insomnia is defined by a Pittsburgh Sleep Quality Index score 〉 7）, the patients were assigned to a simple cerebral infarction group and a cerebral infarction complicated by insomnia group, with 30 subjects in each group. Thirty additional subjects, who concurrently received examinations and were confirmed to not suffer from cerebral infarction and insomnia, were recruited into the control group. Written informed consent was obtained from each subject for laboratory specimens. The protocol was approved by the Hospital＇s Ethics Committee. METHODS： Following admission, each subject＇s neurological impairment was assessed with the National Institutes of Health Stroke Scale and Pittsburgh Sleep Quality Index. Heart rate variability of each subject was measured with an autonomic

关键词： heart rate variability cerebral infarction dyssomnia

Improvement of Centroid Location Algorithm for Wireless Sensor Networks

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Improvement of Centroid Location Algorithm for Wireless Sens...

Risk Factors for Age-Related Macular Degeneration in Elderly Chinese Population in shenyang of China

2011 International Conference on Computer Science and Information Technology(ICCSIT 2011)

作者： xueli shen Huan Zhang School of Electronics and Information Engineering Liaoning Technical University

ISBN: (纸本)9781612848334

In this paper, the radio propagation path loss is analyzed and the previous weighted centroid location algorithm is improved. The weighted factor in the algorithm is optimized, which makes positioning error and positioning accuracy of the unknown nodes better. Firstly, the paper uses three-point location to calculate location of unknown nodes approximately. Secondly, the paper uses a modified weighted centroid location algorithm to calculate the unknown nodes precisely. Finally, the algorithm is simulated. Compared to the previous weighted centroid localization algorithm, the simulation results show that the improved centroid positioning algorithm has better positioning performance.

关键词： wireless sensor networks location algorithm unknown nodes.

来源： cnki会议评论

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Biomedical and Environmental Sciences 2011年第5期24卷 506-511页

作者： JIA LiHong shen xueli FAN Rui SUN Yan PAN XingYue YANH HongMei LIU Lu School of Public Health China Medical University Shenyang 110001 Liaoning China Department of Neurology The First Affiliated Hospital China Medical University Shenyang 110001 Liaoning China shenyang AIER Ophthalmology Hospital Shenyang 110005 Liaoning China Heshi Ophthalmology Hospital Shenyang 110034 Liaoning China

Objective The paper aims to evaluate the risk factors for age‐related macular degeneration （AMD） in elderly Chinese population in shenyang,a northeast city of *** A case‐control study was conducted to investigate the risk factors for the prevalence of *** three AMD patients diagnosed by a complete ophthalmic examination were recruited as cases from the outpatient departments of two eye hospitals in shenyang,while 108 normal subjects of similar age and sex were recruited as controls.A questionnaire was administered among both cases and *** AMD patients aged 60 years and older accounted for 75.3%.There were significantly higher educational levels,shorter smoking history,less sunlight exposure and cataract,and higher proportion of antioxidants intake in controls than in AMD *** frequency of intake of fruits,legumes,fish and shrimps was significantly higher in controls than in AMD *** a binary logistic regression analysis,smoking and cataract were the risk factors for AMD （OR：4.44,95% CI：2.27‐8.69;OR：4.47,95% CI：2.26‐8.85 respectively）.The high educational background was a protective factor for AMD （OR：0.761,95% CI：0.51‐0.98）.Conclusion A low educational background,smoking and cataract are associated with a higher prevalence of AMD.

关键词： Lifestyle Dietary habit Age‐related macular degeneration Chinese people

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基于最佳匹配拍卖的企业级网络资源分配策略

通信学报 2019年第8期40卷 212-222页

作者：丛鑫訾玲玲沈学利辽宁工程技术大学电子与信息工程学院

针对企业级网络中计算机拥有者的自私属性导致网络中可用资源节点数量不足和资源分配效率低的问题,提出一种以拍卖机制为核心的企业级网络最优匹配资源分配(OMRA)策略,在抑制节点自私性的同时提升网络可用资源数,进而提升整个拍卖市场... 详细信息

针对企业级网络中计算机拥有者的自私属性导致网络中可用资源节点数量不足和资源分配效率低的问题,提出一种以拍卖机制为核心的企业级网络最优匹配资源分配(OMRA)策略,在抑制节点自私性的同时提升网络可用资源数,进而提升整个拍卖市场的运行效率。首先,归一化不同类型资源的成本,确定拍卖初始的资源请求价格;其次,设计了最优化匹配的拍卖算法,最大化拍卖市场的收益;再次,运行服务请求预取算法,使资源提供者能以当前的成交价格获取更多的任务请求,保证资源提供者的收益;最后,利用请求价格和竞拍价格更新算法,保证买卖双方在下一轮拍卖过程中获得较高的优先级,以获取更多的收益。实验结果表明,与基于拍卖的云资源分配算法(CRAA/FA)相比,所提OMRA策略能提升10%的资源分配效率和11.4%的市场收益率。

关键词：最佳匹配拍卖服务请求预取企业级网络资源分配

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波动需求库存路径问题的持续自学习求解算法

计算机集成制造系统 2024年第4期30卷 1487-1505页

作者：郭羽含李津宁沈学利浙江科技学院理学院浙江杭州310023 辽宁工程技术大学软件学院辽宁葫芦岛125105

共享单车库存路径问题是一种受商品总量约束且需求周期性波动的库存路径问题,其优化过程需综合考虑资源利用率和调度成本,在求解大规模算例时难以同时保证求解效率和质量。针对上述挑战,将问题形式化为多目标序列化决策的马尔可夫过程,... 详细信息

共享单车库存路径问题是一种受商品总量约束且需求周期性波动的库存路径问题,其优化过程需综合考虑资源利用率和调度成本,在求解大规模算例时难以同时保证求解效率和质量。针对上述挑战,将问题形式化为多目标序列化决策的马尔可夫过程,建立了时间序列混合整数规划模型并提出了一种全局持续自学习算法。算法由离线学习、在线规划和持续学习三阶段构成。离线学习阶段设计了基于随机策略的多智能体协同算法以获取配送载具时空分布和需求点需求模式的定量化描述;在线规划阶段根据历史订单数据,对各时间步中的需求模式进行预测以确定最优的库存分配数量,并利用离线学习阶段的定量信息对供应商配送载具进行调度;持续学习阶段于每个处理周期结束后使用记录的订单数据对周期内调度结果进行持续评估和改进。基于企业真实数据的实验表明,在需求预测模型复杂程度、求解质量、调度载具总数量、总调度距离和站点改善程度等的综合评价指标上,所提算法优于对比方法。此外,通过对多种策略进行对比分析,总结出了库存问题的成本变化规律,并验证了算法在大规模算例下的有效性。

关键词：库存路径产品需求周期波动强化学习在线规划持续学习

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基于自治系统与动态概率包标记的DDoS攻击溯源优化方法

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计算机应用 2015年第6期35卷 1705-1709页

作者：沈学利申杰辽宁工程技术大学电子与信息工程学院辽宁葫芦岛125105

针对分布式拒绝服务(DDo S)攻击对于网络的严重威胁问题,提出基于自治系统(AS)与动态概率包标记(DPPM)的DDo S攻击溯源优化方法。在该方法中,设计了一种新的包标记方案,该方案设置两套标记,分别作为域标记和路由标记,用作域间溯源和域... 详细信息

针对分布式拒绝服务(DDo S)攻击对于网络的严重威胁问题,提出基于自治系统(AS)与动态概率包标记(DPPM)的DDo S攻击溯源优化方法。在该方法中,设计了一种新的包标记方案,该方案设置两套标记,分别作为域标记和路由标记,用作域间溯源和域内溯源。域标记和路由标记过程同时进行,标记过程采用动态包标记的方法。最后,通过域间和域内的路径重构实现对攻击节点的快速溯源。实验结果表明该算法是高效、可行的,能为DDo S攻击的防范提供重要依据。

关键词：分布式拒绝服务攻击自治系统动态概率包标记域间溯源域内溯源

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基于注意力机制的场感知点击率预测模型

计算机工程 2023年第3期49卷 80-86,94页

作者：沈学利韩倩雯辽宁工程技术大学软件学院辽宁葫芦岛125105

点击率预测是广告投放的重要手段之一,通过预测广告点击率对用户进行效推荐,能够提高广告收益。在点击率预测任务中,场感知点击率预测模型由于考虑了场信息,表现出一定优越性,但在进行特征交互时会产生大量冗余信息,导致预测准确率较低... 详细信息

点击率预测是广告投放的重要手段之一,通过预测广告点击率对用户进行效推荐,能够提高广告收益。在点击率预测任务中,场感知点击率预测模型由于考虑了场信息,表现出一定优越性,但在进行特征交互时会产生大量冗余信息,导致预测准确率较低。提出一种场感知注意嵌入神经网络(FAENN)模型,通过自注意力机制对嵌入层的输入向量进行权重分配,以较好地区分场感知嵌入特征的重要程度,加快模型训练速度。同时使用低阶特征交互层关注特征的一阶显性信息和二阶交互特征信息,并将有效特征输出到高阶交互层,利用高阶特征交互层将学习到的相互作用向量与深度神经网络相结合,捕捉更高阶的特征交互作用,以提高预测准确率。实验结果表明,FAENN模型相比于FM、FFM、AFM等模型有较高的预测准确率。

关键词：点击率预测表示学习嵌入技术自注意力机制特征交互

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基于图边缘特征注意力的入侵检测模型

计算机工程 2024年第11期50卷 236-245页

作者：沈学利刘士枫辽宁工程技术大学软件学院辽宁葫芦岛125105

入侵检测是一种网络安全技术,旨在检测和防止未经授权的访问或攻击。现有入侵检测模型对于分布均匀的网络数据具备良好的检测性能,但是网络中相关数据往往是不平衡的,现有模型对少数类攻击数据的检测率低。针对上述问题,提出一种基于图... 详细信息

入侵检测是一种网络安全技术,旨在检测和防止未经授权的访问或攻击。现有入侵检测模型对于分布均匀的网络数据具备良好的检测性能,但是网络中相关数据往往是不平衡的,现有模型对少数类攻击数据的检测率低。针对上述问题,提出一种基于图边缘特征注意力的入侵检测模型。首先,挖掘数据内部隐藏的图结构关系,并将数据进行归一化处理,对样本数据的原始特征进行更新,将数据转换成图结构;其次,使用图池化操作对图节点进行下采样,降低计算复杂度,利用图边缘特征注意力对采样后的图进行边缘特征加权聚合,提高模型的表征能力,将聚合后的边缘特征与节点特征拼接,生成节点嵌入,拼接源节点与目标节点嵌入形成边缘嵌入;最后,将边缘嵌入输入分类器转换成类别概率进行分类。在数据集UNSW-NB15和NSL_KDD上的对比实验结果表明,该模型能够有效检测出少数类攻击数据,相比现有模型提升了对不平衡数据的检测精度,多分类检测准确率分别达到0.9929和0.9766。

关键词：入侵检测不平衡数据图神经网络图边缘特征注意力边缘分类

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一种改进的无线传感器网络DV-Hop定位算法

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计算机工程 2015年第7期41卷 115-119页

作者：沈学利陈光辽宁工程技术大学电子与信息工程学院辽宁葫芦岛125105

针对现有无线传感器网络DV-Hop算法定位精度低、锚节点成本高的问题,给出最小偏离度的概念,并在此基础上提出一种改进算法AADV-Hop。通过寻找最小偏离度降低定位算法整体的平均定位误差,采用锚节点间的真实距离修正未知节点到锚节点距... 详细信息

针对现有无线传感器网络DV-Hop算法定位精度低、锚节点成本高的问题,给出最小偏离度的概念,并在此基础上提出一种改进算法AADV-Hop。通过寻找最小偏离度降低定位算法整体的平均定位误差,采用锚节点间的真实距离修正未知节点到锚节点距离的计算方法,以替代传统DV-Hop算法通过跳数与平均跳距的乘积得到的距离。仿真结果表明,当网络中锚节点数量较少时,AADV-Hop算法可有效提高定位精度,当最小偏离度为0.03时定位精度最高。

关键词：无线传感器网络 DV-Hop算法最小偏离度锚节点定位精度