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乡村休闲度假旅游景区暴雨防灾减灾能力评价研究

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河北北方学院学报（自然科学版） 2024年第1期40卷 50-55页

作者：周梅吴超徐明伟合肥滨湖职业技术学院教育科学学院安徽合肥230601

为了提升景区防灾减灾能力,提出乡村休闲度假旅游景区暴雨防灾减灾能力评价方法。经致灾分析后,构建包含预警能力、应急能力、管理能力、重建能力4项一级指标的暴雨防灾减灾能力评价指标体系。依据评价指标体系构建评价模型,根据评价指... 详细信息

为了提升景区防灾减灾能力,提出乡村休闲度假旅游景区暴雨防灾减灾能力评价方法。经致灾分析后,构建包含预警能力、应急能力、管理能力、重建能力4项一级指标的暴雨防灾减灾能力评价指标体系。依据评价指标体系构建评价模型,根据评价指标等级标准,利用隶属度函数得到单指标测度评价矩阵。结合相似权法获取评价矩阵中相应指标权重,明确各指标在景区暴雨防灾减灾评价中重要程度,实现景区暴雨防灾减灾能力评价。以某地区乡村休闲度假旅游景区降雨数据为例进行模型检验,模型检验结果表明,所构建模型评价出的乡村休闲度假旅游景区预警能力指标权重值最高。根据评价结果,建议在未来的暴雨防灾减灾工作中,应以监测预警为重点关注对象,进一步保护旅游景区游客的生命财产安全。

关键词：乡村休闲度假旅游景区暴雨防灾减灾

SA-MGKT:基于自注意力融合的多图知识追踪方法

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华东师范大学学报（自然科学版） 2024年第5期 20-31页

作者：王畅马丹许华容陈攀峰陈梅李晖公共大数据国家重点实验室贵阳550025 贵州大学计算机科学与技术学院贵阳550025

提出了一种基于自注意力融合的多图知识追踪方法(multi-graph knowledge tracing method based on self-attention,SA-MGKT),旨在通过学生的历史答题数据,对其知识的掌握程度进行模型化,并评估其未来学习的表现.首先,该方法构建了学生... 详细信息

提出了一种基于自注意力融合的多图知识追踪方法(multi-graph knowledge tracing method based on self-attention,SA-MGKT),旨在通过学生的历史答题数据,对其知识的掌握程度进行模型化,并评估其未来学习的表现.首先,该方法构建了学生–习题异质图来表示学生–习题的高阶关系,通过图对比学习技术捕获学生的答题偏好,并采用3层LightGCN进行图表征学习.然后,引入概念关联超图和有向转换图的信息,通过超图卷积网络和有向图卷积网络进行节点嵌入.最后,通过引入自注意力机制,成功融合了习题序列的内部信息以及多图表征学习所蕴含的潜在信息,从而显著提升了知识追踪模型的准确性.实验数据在3个标准数据集上均展现出令人鼓舞的结果,模型的分类性能得到了大幅提升,具体表现为相对于基线模型,在评估指标上分别提高了3.51%、17.91%和1.47%.这些结果充分验证了融合多图信息和自注意力机制对于增强知识追踪模型性能的有效性.

关键词：知识追踪图对比学习自注意力机制

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烫漂结合氯化钙对大头菜预处理工艺研究

中国调味品 2024年第10期49卷 81-88页

作者：周莺茹袁先铃杜冬梅林洪斌四川轻化工大学生物工程学院四川宜宾644005 西华大学食品与生物工程学院成都610039

为抑制或延缓大头菜在加工过程中易软化的问题,该研究通过添加氯化钙,结合低温漂烫以探究大头菜的预处理工艺。通过测定漂烫时间、漂烫温度、氯化钙添加量对脆度、果胶甲酯酶(PE)活性、果胶酸钙含量和品质指标的影响,采用逼近于理想值... 详细信息

为抑制或延缓大头菜在加工过程中易软化的问题,该研究通过添加氯化钙,结合低温漂烫以探究大头菜的预处理工艺。通过测定漂烫时间、漂烫温度、氯化钙添加量对脆度、果胶甲酯酶(PE)活性、果胶酸钙含量和品质指标的影响,采用逼近于理想值的排序(TOPSIS)综合评价法得到最佳工艺条件为漂烫时间15 min、漂烫温度55℃、氯化钙添加量0.15%。扫描电镜(SEM)结果表明,经过该工艺预处理的大头菜能够明显抑制其在腌制过程中的软化,以期为大头菜的加工工艺提供理论参考。

关键词：大头菜漂烫氯化钙预处理工艺

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基于现场可编程门阵列的水果识别系统设计

高技术通讯 2024年第6期34卷 616-623页

作者：金梅曾欣张立国冯景瑞吴文哲燕山大学电气工程学院秦皇岛066004 燕山大学信息科学与工程学院秦皇岛066004

针对目前大多数水果识别系统实时性差和成本较高的问题,本文提出一种基于现场可编程门阵列(FPGA)的水果识别系统。整体硬件设计包含图像采集、检测识别和显示模块。软件部分通过图像采集平台将水果图像存储至双倍数据率同步动态随机存储... 详细信息

针对目前大多数水果识别系统实时性差和成本较高的问题,本文提出一种基于现场可编程门阵列(FPGA)的水果识别系统。整体硬件设计包含图像采集、检测识别和显示模块。软件部分通过图像采集平台将水果图像存储至双倍数据率同步动态随机存储器(DDR3)控制模块,进行图像灰度化处理,并创造性地提出背景帧差法对水果图像进行分割。通过融合水果颜色和几何特征,实现对水果数量、颜色和种类的识别。整个水果识别系统在不同光照下对常见水果进行了测试。实验结果表明,水果平均识别准确率达到93.25%,识别速度约为16.67 ms,FPGA硬件资源消耗率仅占28.02%,可以满足实时性需求。

关键词：水果识别背景帧差法图像处理现场可编程门阵列(FPGA)

氮掺杂生物炭的制备及其对亚甲基蓝的吸附性能研究

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无机盐工业 2024年第9期56卷 117-127页

作者：王萍徐荣声孙冬史小红徐炜李梅北方民族大学化学与化学工程学院宁夏银川750021 北方民族大学国家民委化工技术基础重点实验室宁夏银川750021

采用生物质枸杞杆为原料、KHCO_(3)为活化剂、尿素为氮源,制备枸杞杆氮掺杂生物炭。利用氮气吸附-脱附仪、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、拉曼光谱(Raman)、傅里叶变换红外光谱(FT-IR)和X射线光电子能谱(XPS)等分析所制生物... 详细信息

采用生物质枸杞杆为原料、KHCO_(3)为活化剂、尿素为氮源,制备枸杞杆氮掺杂生物炭。利用氮气吸附-脱附仪、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、拉曼光谱(Raman)、傅里叶变换红外光谱(FT-IR)和X射线光电子能谱(XPS)等分析所制生物炭的形貌、结构和表面官能团等特性,并探析其对水中亚甲基蓝(MB)的吸附行为。结果表明,KHCO_(3)活化枸杞杆的最佳条件:m(枸杞杆炭化料)∶m(KHCO_(3))=1∶2、活化温度为800℃、活化时间为1 h。在枸杞杆生物炭(LBC)表面掺杂尿素的最佳条件:LBC与尿素的负载比为1∶4(质量比),800℃下煅烧1 h,得到氮掺杂生物炭(LBC-N)。LBC和LBC-N的比表面积分别为940.29 m^(2)/g和1169.78 m^(2)/g,总孔体积分别为0.57 cm^(3)/g和0.72 cm^(3)/g,平均孔径分别为5.81 nm和3.20 nm,均是以介孔为主的生物质活性炭材料。在相应实验条件下,LBC和LBC-N对MB的吸附量分别为542.02 mg/g和639.20 mg/g。准二级动力学模型、颗粒内扩散模型和Langmuir等温模型能很好地描述LBC和LBC-N对MB的吸附过程。根据氮掺杂生物炭的理化性质和吸附实验,LBC-N对MB分子的吸附过程是以π-π相互作用、氢键作用、静电吸引作用等化学作用为主,孔隙填充物理吸附协同作用的结果。

关键词：枸杞杆氮掺杂生物炭尿素吸附亚甲基蓝

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Weighted Nuclear Norm Minimization-Based Regularization Method for Image Restoration

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Communications on Applied Mathematics and Computation 2021年第3期3卷 371-389页

作者： Yu-mei Huang Hui-Yin Yan Key Laboratory of Applied Mathematics and Complex Systems School of Mathematics and StatisticsLanzhou UniversityLanzhou730000China School of Mathematics and Statistics Xinyang Normal UniversityXinyang 464000Henan ProvinceChina

Regularization methods have been substantially applied in image restoration due to the ill-posedness of the image restoration *** assumptions or priors on images are applied in the construction of image regularization *** recent years,matrix low-rank approximation has been successfully introduced in the image denoising problem and significant denoising effects have been ***-rank matrix minimization is an NP-hard problem and it is often replaced with the matrix’s weighted nuclear norm minimization(WNNM).The assumption that an image contains an extensive amount of self-similarity is the basis for the construction of the matrix low-rank approximation-based image denoising *** this paper,we develop a model for image restoration using the sum of block matching matrices’weighted nuclear norm to be the regularization term in the cost *** alternating iterative algorithm is designed to solve the proposed model and the convergence analyses of the algorithm are also *** experiments show that the proposed method can recover the images much better than the existing regularization methods in terms of both recovered quantities and visual qualities.

关键词： Image restoration Regularization method Weighted nuclear norm Alternating iterative method

Certain Subsets on Which Every Bounded Convex Function Is Continuous

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Acta Mathematica Sinica,English Series 2007年第6期23卷 1063-1066页

作者： Li Xin CHENG Yan mei TENG School of Mathematical Sciences Xiamen University Xiamen 361005 P. R. China Department of Mathematics Beijing University of Aeronautics and Astronautics Beijing 100083 P. R. China

To guarantee every real-valued convex function bounded above on a set is continuous, how ＂thick＂ should the set be？ For a symmetric set A in a Banach space E,the answer of this paper is： Every real-valued convex function bounded above on A is continuous on E if and only if the following two conditions hold： i） spanA has finite co-dimentions and ii） coA has nonempty relative interior. This paper also shows that a subset A C E satisfying every real-valued convex function bounded above on A is continuous on E if （and only if） every real-valued linear functional bounded above on A is continuous on E, which is also equivalent to that every real-valued convex function bounded on A is continuous on E.

关键词： Convex function Boundedness Continuity Banach space

Experimental study on permanent deformation characteristics of coarse-grained soil under repeated dynamic loading

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Railway Engineering Science 2021年第1期29卷 94-107页

作者： Huihao mei Sajjad Satvati Wuming Leng China Railway 11 Bureau Group Co. Ltd.Wuhan 430061China Terracon Consultants IncOmahaNE 68144USA Department of Geotechnical Engineering School of Civil EngineeringCentral South UniversityChangsha 410075China

Practical assessment of subgrade settlement induced by train operation requires developing suitable models capable of describing permanent deformation characteristics of subgrade filling under repeated dynamic *** this paper,repeated load triaxial tests were performed on coarse-grained soil(CGS),and the axial permanent strain of CGS under different confining pressures and dynamic stress amplitudes was *** deformation behaviors of CGS were categorized based on the variation trend of permanent strain rate with accumulated permanent strain and the shakedown theory.A prediction model of permanent deformation considering stress state and number of load cycles was established,and the ranges of parameters for different types of dynamic behaviors were also *** results indicated that the variational trend of permanent strain rate with accumulated permanent strain can be used as a basis for classifying dynamic behaviors of *** stress state(confining pressure and dynamic stress amplitude)has significant effects on the permanent strain *** accumulative characteristics of permanent deformation of CGS with the number of load cycles can be described by a power function,and the model parameters can reflect the influence of confining pressure and dynamic stress *** study’s results could help deepen understanding of the permanent deformation characteristics of CGS.

关键词： Repeated load triaxial tests Coarse grained soil Shakedown theory Dynamic stress Accumulated permanent strain Railway subgrade

Effects of benthic algae on release of soluble reactive phosphorus from sediments: a radioisotope tracing study

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Water Science and Engineering 2015年第2期8卷 127-131页

作者： Xiu-feng Zhang Xue-ying mei Department of Ecology and Institute of Hydrobiology Jinan University College of Resources and Environment Anhui Agricultural University

To evaluate the effect of benthic algae on soluble reactive phosphorus（SRP） release from sediments in shallow lakes, experiments on SRP release with and without benthic algae in sediment cores and an experiment on SRP uptake by benthic algae were conducted using the radioisotope（32P） tracing method. The dissolved oxygen（DO） concentration in sediment cores was also investigated. The results show that benthic algae effectively reduce the release of SRP from sediments to overlying water. The uptake of SRP by benthic algae, which is the direct way in which benthic algae affect the SRP release from sediments, is low in filtered water and increases with the SRP concentration. However, in the experiment, the increased uptake rate lasted for a short time（in one hour）, and after that it returned to a low rate. Benthic algae make the DO concentration and the oxic layer thickness increased, which can indirectly reduce the SRP release from sediments. These findings indicate that benthic algae can reduce the SRP release from sediments in both direct and indirect ways. It seems that the indirect way also plays an important role in reducing the SRP release from sediments.

关键词： Sediment Benthic algae Soluble reactive phosphorus release Soluble reactive phosphorus uptake Shallow lake