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基于小波变换算法的普朗铜矿爆破振动信号能量分布研究

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中国矿业 2024年第3期33卷 226-234页

作者：刘明武黄永辉李争荣贾皓琦甘等俊李洪超张智宇云南迪庆有色金属有限责任公司云南迪庆674400 昆明理工大学电力工程学院云南昆明650500 昆明理工大学国土资源工程学院云南昆明650093 昆明理工大学城市学院云南昆明650051

小波变换算法能够对爆破振动信号的频率、能量分布特征进行研究,按照不同的主振频带对爆破振动信号进行分解及重构,已被广泛应用于爆破振动稳定性分析以及矿山安全生产管理。针对在矿山复杂条件下爆破振动信号易受干扰等问题,以普朗铜... 详细信息

小波变换算法能够对爆破振动信号的频率、能量分布特征进行研究,按照不同的主振频带对爆破振动信号进行分解及重构,已被广泛应用于爆破振动稳定性分析以及矿山安全生产管理。针对在矿山复杂条件下爆破振动信号易受干扰等问题,以普朗铜矿南部拉底爆破振动数据为研究对象,采用小波变换算法分析振动信号0~125 Hz各个频率段能量分布情况,通过HHT算法、STFT算法分别对爆区近区、爆区远区开展能量分布及其衰减规律的研究。研究结果表明:在0~125 Hz频率段范围内,爆区近区和爆区远区能量衰减速度和分布不同,爆区近区能量主振频率分布在15.62~<31.20 Hz频率段,爆区远区能量主振频率分布在46.87~<93.75 Hz频率段。在15.62~<31.20 Hz频率段,爆区近区比爆区远区能量占比平均多出14.1%;在46.87~<93.75 Hz频率段,爆区远区比爆区近区能量占比平均多出18.65%。基于本次爆破施工所监测到的普朗铜矿南部巷道区域爆破振动数据得出,在0~125 Hz频率段范围内,爆区近区能量衰减速度较快且能量分布不集中,爆区远区能量衰减速度较为缓慢且能量分布密集;爆破振动能量随着传播距离增加,能量虽有所衰减,但能量分布更为集中。分析结果表明,小波变换算法可以真实反映振动信号的能量分布情况,为研究爆破振动效应下的井下构筑物的结构安全提供有效的分析手段。

关键词：小波变换爆破振动能量分布 HHT算法 STFT算法主振频率

Numerical Method Based on Compatible Manifold Element for Thin Plate Bending

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Chinese Journal of Mechanical Engineering 2010年第1期23卷 100-109页

作者： zhang zhengrong zhang Xiangwei Lu Wenge Faculty of Materials and Energy Guangdong University of Technology Guangzhou 510006 China Faculty of Electromeehanical Engineering Guangdong University of Technology Guangzhou 510006 China

The typical quadrangular and triangular elements for thin plate bending based on Kirchhoff assumptions are the non- conforming elements with low computational accuracy and limitative application range in fmite element method（FEM）. Some compatible elements can be developed by the means of supplementing correction functions, increasing nodes in element or on the boundaries, expanding nodal degrees of freedom（DOF）, etc, but these elements are inconvenient to apply in practice for the high calculation complexity. In this paper, in order to overcome the defects of thin plate bending finite element, numerical manifold method（NMM） was introduced to solve thin plate bending deformation problem. Rectangular mesh was adopted as mathematical mesh to form f＇mite element cover system, and then 16-cover manifold element was proposed. Numerical manifold formulas were constructed on the basis of minimum potential energy principle, displacement boundary conditions are implemented by penalty function method, and all the element matrixes were derived in details. The 16-cover element has a simple calculation process for employing only the transverse displacement cover DOFs as the basic unknown variables, and has been proved to meet the requirements of completeness and full compatibility. As an application, the presented 16-cover element has been used to analyze bending deformation of square thin plate under different loads and boundary conditions, and the results show that numerical manifold method with compatible element, compared with finite element method, can improve computational accuracy and convergence greatly.

关键词： thin plate bending numerical manifold method compatible element 16-cover manifold element

甲基二乙醇胺-二元胺混合体系烟气CO_(2)吸收再生性能研究

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发电技术 2024年第3期45卷 468-477页

作者：孙宇航李超王争荣孙路长王凯亮胡昔鸣方梦祥张锋能源高效清洁利用全国重点实验室(浙江大学) 浙江省杭州市310027 中国华电科工集团有限公司北京市丰台区100160 浙江大学青山湖能源研究基地浙江省杭州市311300 国网浙江省电力有限公司建设分公司浙江省杭州市310008

【目的】研究甲基二乙醇胺(MDEA)与不同二元胺混合后配方的吸收再生性能。【方法】在体积分数12%的CO_(2)和88%的N_(2)模拟烟气环境下,以MDEA为主剂,分别添加乙二胺(EDA)、1,3-丙二胺(DAP)、3-甲氨基丙胺(MAPA)、羟乙基乙二胺(AEEA)、 N... 详细信息

【目的】研究甲基二乙醇胺(MDEA)与不同二元胺混合后配方的吸收再生性能。【方法】在体积分数12%的CO_(2)和88%的N_(2)模拟烟气环境下,以MDEA为主剂,分别添加乙二胺(EDA)、1,3-丙二胺(DAP)、3-甲氨基丙胺(MAPA)、羟乙基乙二胺(AEEA)、 N, N-二甲基乙二胺(DMEDA)和N,N-二甲基-1,3-丙二胺(DMPDA)作为活化剂。在总胺质量分数为40%的条件下,以主剂与活化剂的质量比1∶1、2∶1、3∶1配置化学吸收剂。通过比较鼓泡吸收和油浴再生实验,得到不同吸收剂的吸收速率、再生速率和循环容量,筛选出性能优良的吸收剂配方。【结果】MDEAEDA体系在MDEA与EDA的质量比1∶1时吸收性能最佳;MDEA-DMEDA体系在MDEA与DMEDA的质量比2∶1时再生性能最佳,循环容量达到1.7 mol/kg;MDEA-AEEA体系在MDEA与AEEA的质量比1∶1时整体性能达到最优,循环容量可以达到1.49 mol/kg。【结论】研究结果可为工业上混合胺液的配方优选提供理论依据。

关键词：碳捕集、利用与封存(CCUS) 吸收性能再生性能甲基二乙醇胺(MDEA) 二元胺

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某离心压气机转子叶尖流场测试及可视化分析

测控技术 2024年第1期43卷 83-88页

作者：高倩张一弛姚峥嵘马宏伟郭君德中国航发湖南动力机械研究所湖南株洲412002 北京航空航天大学能源与动力工程学院北京100191

对壁面动态压力传感器阵列测试技术进行了研究,并将该技术应用于某离心压气机转子叶尖的动态流场测试中,获取了大量的动态流场测试数据。采用锁相技术和线性插值方法对测试数据进行了处理和分析,并采用数据可视化技术将动态数据转化成... 详细信息

对壁面动态压力传感器阵列测试技术进行了研究,并将该技术应用于某离心压气机转子叶尖的动态流场测试中,获取了大量的动态流场测试数据。采用锁相技术和线性插值方法对测试数据进行了处理和分析,并采用数据可视化技术将动态数据转化成压力分布云图,从云图中可以清楚看出离心压气机不同工作状态下转子叶尖的压力变化,有助于分析转子叶尖处泄漏流、前缘溢流以及泄漏流和分流叶片前缘的相互作用。转子叶尖流场测试及可视化分析结果可以为压气机性能验证和数值模拟方法的修正提供重要的技术支撑。

关键词：压气机转子叶尖壁面动态压力阵列测试可视化分析

SETD2 mediates immunotherapy and radiotherapy efficacy via regulating DNA damage responses and genomic stability in lung adenocarcinoma

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Genes & Diseases 2023年第2期10卷 336-339页

作者： Zihang Zeng Yanping Gao Jiali Li Jianguo zhang Yangyi Li Fajian He zhengrong Huang Linzhi Han Yan Gong Conghua Xie Department of Radiation and Medical Oncology Zhongnan Hospital of Wuhan UniversityWuhanHubei 430071China Department of Biological Repositories Zhongnan Hospital of Wuhan UniversityWuhanHubei 430071China Tumor Precision Diagnosis and Treatment Technology and Translational Medicine Hubei Engineering Research CenterZhongnan Hospital of Wuhan UniversityWuhanHubei 430071China Hubei Key Laboratory of Tumor Biological Behaviors Zhongnan Hospital of Wuhan UniversityWuhanHubei 430071China Hubei Cancer Clinical Study Center Zhongnan Hospital of Wuhan UniversityWuhanHubei 430071China

SETD2 is the main transferase for the trimethylation of histone H3 at lysine 36 (H3K36me3) in mammals. SETD2 plays important role in repairing DNA double strand breaks and maintaining chromatin integrity.1 In renal carcinoma, SETD2 deficiency caused DNA replication fork instability and DNA damage.2 The absence of SETD2 was also reported to have strong tumor-promoting effects in lung adenocarcinomas (LUAD).3 However, the other roles of SETD2 remain poorly understood in LUAD. In this study, we utilized comprehensive omics-data analysis to determine that SETD2 was associated with DNA damage and immune-related signals in LUAD. SETD2 knockdown induced DNA damage and cGAS activation in LUAD cells, and reduced the number of cells at the G1 phase. Moreover, SETD2 deficiency was conducive to mutation burden, immune cell infiltration, and immunotherapy responses. High SETD2 expression was associated with high radiocurability. These findings suggest that SETD2 may be a promising biomarker of therapeutic responses for LUAD patients, and offer novel insights into immunotherapy and radiotherapy.

关键词： SETD2 damage immunotherapy

益生菌缓解金黄色葡萄球菌感染牛乳腺炎的研究与应用进展

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中国乳品工业 2024年第1期52卷 33-39页

作者：朱妍刘慧燕闫丹丽赵春光滕政蓉张英刘晓燕方海田武俊瑞沈阳农业大学食品学院辽宁省食品发酵技术工程研究中心沈阳市微生物发酵技术创新重点实验室沈阳110866 宁夏食品微生物应用技术与安全控制重点实验室宁夏大学食品与葡萄酒学院银川750021 宁夏伊品生物科技股份有限公司银川750001

金黄色葡萄球菌(Staphylococcus aureus,S. aureus)感染牛乳腺引发炎症。研究表明益生菌对缓解牛乳腺炎有一定作用,且相对于抗生素更加安全。本文对S. aureus的致病机理、益生菌在牛乳腺炎中的作用机制及应用等进行了综述。明确S. aureu... 详细信息

金黄色葡萄球菌(Staphylococcus aureus,S. aureus)感染牛乳腺引发炎症。研究表明益生菌对缓解牛乳腺炎有一定作用,且相对于抗生素更加安全。本文对S. aureus的致病机理、益生菌在牛乳腺炎中的作用机制及应用等进行了综述。明确S. aureus通过释放毒力因子,其中黏蛋白帮助病原菌定植细胞表面同时大量S. aureus生成生物膜破坏细胞结构引发“细胞因子风暴”,干扰机体免疫系统识别。S. aureus入侵牛乳腺上皮细胞(bovine mammary epithelial cells,bMEC)后激活信号通路以及相关蛋白的表达,通过分析其入侵乳腺上皮细胞后能够破坏上皮细胞屏障,干扰机体免疫系统3个方面说明S. aureus能够在bMEC存活的干扰因素。并且从益生菌角度总结已有发现益生菌在体内定植可增强肠道完整性、抑制病原菌的生长,提高机体免疫力从而抑制S. aureus对bMEC的黏附和侵染,降低S. aureus生物膜的形成,以减少S. aureus在乳腺内的定植,从而起到减轻乳腺感染效果。

关键词：金黄色葡萄球菌牛乳腺炎益生菌发病机制机体免疫

The Strength and Microstructure Properties of Oil Well Cement with Halloysite Nanotube

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The Strength and Microstructure Properties of Oil Well Cemen...

深圳市男男性行为者HIV暴露后预防的使用:一项系列横断面研究

作者： Huiting Liu Ming Xu zhengrong zhang Shuoqiong Liu Hua zhang Chi zhang Jiawen Fu Mi Cong Zhifang Li

Halloysite nanotube has attracted more and more attention to reinforce cement for its excellent physical properties and chemical composition.In this study,effects of halloysite nanotube on compressive strength,flexural strength,micro-structure and hydration products of oil well cement were investigated.The results show that the compressive and flexural strength of cement with 3% halloysite nanotube was increased by 35.2% and 38.5%,and the porosity decreased by 14.95%,respectively.Based on the results of SEM and MIP,the following conclusions can be obtained.Halloysite nanotube promoted the hydration process because of its high surface area,filled in the pores of hardened cement paste for the nano size and expansion process,and formed cross-linking structure for the tube-like appearance,all of which lead to denser micro-structure and better strength performance of oil well cement eventually.

关键词： Halloysite nanotube Cement Compressive strength Flexural strength Pore structure

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中国艾滋病性病 2024年第1期30卷 18-22页

作者：戴德磊杨梓杰张燕谭唯杨峥嵘刘少础谢炜卫兰李思美袁苑袁小洪唐虎朱悦赵锦汕头大学公共卫生学院广东汕头515063 深圳市疾病预防控制中心广东深圳518000 北京大学北京100083 中山大学公共卫生学院广州510080 山西医科大学公共卫生学院山西太原030607 南方医科大学广州510515

目的分析2020-2022年深圳市MSM的nPEP使用情况及其影响因素。方法2020年1月至2022年12月,在深圳市通过与社会组织合作招募MSM开展问卷调查,收集人口学、行为学以及nPEP使用等信息。采用χ2检验和Logistic回归分析nPEP使用的影响因素。... 详细信息

目的分析2020-2022年深圳市MSM的nPEP使用情况及其影响因素。方法2020年1月至2022年12月,在深圳市通过与社会组织合作招募MSM开展问卷调查,收集人口学、行为学以及nPEP使用等信息。采用χ2检验和Logistic回归分析nPEP使用的影响因素。结果共2900名研究对象纳入分析,2020-2022年深圳市MSM中三年的nPEP使用率依次为7.00%(55/787)、5.00%(59/1183)和5.59%(52/930)。多因素Logistic回归结果显示:有药物滥用(aOR=1.720,95%CI:1.242~2.381)、近一年在诊所或男同场所接受艾滋病相关服务(aOR=1.741,95%CI:1.068~2.836)、有启动PrEP的意愿(aOR=3.299,95%CI:2.256~4.832)、过去一年确诊患有性传播疾病(aOR=1.849,95%CI:1.139~3.000)、有做包皮环切术的历史(aOR=1.591,95%CI:1.029~2.459)的MSM使用nPEP的概率更高,而有固定性伴侣的MSM(aOR=0.532,95%CI:0.375~0.755)、有套肛交性行为(aOR=0.377,95%CI:0.230~0.619)使用nPEP的概率更低。结论2020-2022年深圳市MSM的nPEP使用率不高,有必要开展针对性的教育宣传,重点关注有固定性伴侣和有套肛交性行为的人群,提高nPEP使用率。

关键词：艾滋病病毒非职业暴露后预防男男性行为者影响因素

Energy enhanced tissue texture in spectral computed tomography for lesion classification

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Visual Computing for Industry,Biomedicine,and Art 2019年第1期2卷 138-149页

作者： Yongfeng Gao Yongyi Shi Weiguo Cao Shu zhang zhengrong Liang Department of Radiology Stony Brook UniversityStony BrookNY 11794USA Institute of Image Processing and Pattern Recognition Xi’an Jiaotong UniversityXi’an 710049ShanxiChina Departments of Radiology Biomedical EngineeringComputer Scienceand Electrical EngineeringStony Brook UniversityStony BrookNY 11794USA

Tissue texture reflects the spatial distribution of contrasts of image voxel gray levels,i.e.,the tissue heterogeneity,and has been recognized as important biomarkers in various clinical tasks.Spectral computed tomography(CT)is believed to be able to enrich tissue texture by providing different voxel contrast images using different X-ray energies.Therefore,this paper aims to address two related issues for clinical usage of spectral CT,especially the photon counting CT(PCCT):(1)texture enhancement by spectral CT image reconstruction,and(2)spectral energy enriched tissue texture for improved lesion classification.For issue(1),we recently proposed a tissue-specific texture prior in addition to low rank prior for the individual energy-channel low-count image reconstruction problems in PCCT under the Bayesian theory.Reconstruction results showed the proposed method outperforms existing methods of total variation(TV),low-rank TV and tensor dictionary learning in terms of not only preserving texture features but also suppressing image noise.For issue(2),this paper will investigate three models to incorporate the enriched texture by PCCT in accordance with three types of inputs:one is the spectral images,another is the cooccurrence matrices(CMs)extracted from the spectral images,and the third one is the Haralick features(HF)extracted from the CMs.Studies were performed on simulated photon counting data by introducing attenuationenergy response curve to the traditional CT images from energy integration detectors.Classification results showed the spectral CT enriched texture model can improve the area under the receiver operating characteristic curve(AUC)score by 7.3%,0.42%and 3.0%for the spectral images,CMs and HFs respectively on the five-energy spectral data over the original single energy data only.The CM-and HF-inputs can achieve the best AUC of 0.934 and 0.927.This texture themed study shows the insight that incorporating clinical important prior information,e.g.,tissue texture in this paper,into the medical imagin

关键词： Tissue texture Spectral computed tomography Lesion classification Machine learning Bayesian reconstruction