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Journal of Thermal Science 2022年第6期31卷 2411-2423页

作者： PENG Zhigang OUYANG Hua WU Yadong tian jie School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Brose Electric Motors Company Limited Shanghai 201801China

To optimize the aerodynamic performance of the automobile cooling fan(ACF), the internal flow field of the original fan was numerically simulated. According to the theory of boundary vorticity dynamics(BVD), the distribution laws of the boundary vorticity flux(BVF) on the blade surface and the circumferential vorticity(CV) at the wake plane of the fan were analyzed, and the underlying various negative factors, such as vortex shedding, separated flow and complicated secondary flow, on the fan blade surface and its dynamic source were diagnosed. Combined with the velocity triangle theory, the mathematical relationship between the BVF diagnosis and the geometrical characteristics of the blade profile(hereinafter referred to as profile) is used to guide the design improvement of the blade. The analysis found that at the same speed, the extension and rotation of the profile could match a smaller input torque at the same flow rate and pressure rise, thereby improving the efficiency of the fan. The test results confirmed the above conclusion. The peak efficiency of the improved fan has been increased by 2.3%, and the aerodynamic performance in the low-flow-rate has been improved. The conclusion of the study shows the applicability of the BVD theory in the diagnosis and design improvement of ACF internal flow.

关键词： boundary vorticity flux automotive cooling fan design improvement blade profile

管中管流体流动与管柱变形测量实验平台设计与测试

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实验技术与管理 2024年第6期41卷 64-69页

作者：孙巧雷田杰刘语维金雨杰冯定长江大学机械工程学院湖北荆州434020 湖北省油气钻完井工具工程技术研究中心湖北荆州434020

基于海上管中管结构承载特性设计了管中管流体流动与管柱变形测量实验平台。该实验平台可更换不同的内管尺寸,研究不同管柱组合的变形和海水流动响应,能够通过调节外管外流速度、内管内流速度、顶部张紧力大小及水深等模拟海上管中管流... 详细信息

基于海上管中管结构承载特性设计了管中管流体流动与管柱变形测量实验平台。该实验平台可更换不同的内管尺寸,研究不同管柱组合的变形和海水流动响应,能够通过调节外管外流速度、内管内流速度、顶部张紧力大小及水深等模拟海上管中管流体流动和变形特性。该实验平台可帮助学生加深对海上管中管的结构、原理及其作用的理解,提高专业兴趣,还可以进行管中管结构动态响应创新性实验研究,培养创新意识,提高解决复杂工程问题的能力。

关键词：管中管流体流动变形实验平台测试

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基于CEEMD的露天深孔爆破振动信号降噪光滑模型

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爆破 2024年第2期41卷 143-150,159页

作者：田婕张云鹏闫鹏孙文诚杨曦华北理工大学矿业工程学院唐山063210 河北省矿业开发与安全技术重点实验室唐山063210 承德广兴矿业有限责任公司承德067103

由于爆破区域地形地质条件的复杂、监测仪器的误差、振动传播介质的反射以及磁场的干扰等原因,采集的原始爆破振动信号常常会掺杂大量的噪声,针对此问题提出了基于互补集合经验模态分解(CEEMD)的信号降噪光滑模型。此模型将爆破振动信... 详细信息

由于爆破区域地形地质条件的复杂、监测仪器的误差、振动传播介质的反射以及磁场的干扰等原因,采集的原始爆破振动信号常常会掺杂大量的噪声,针对此问题提出了基于互补集合经验模态分解(CEEMD)的信号降噪光滑模型。此模型将爆破振动信号进行CEEMD,基于分解所得到的IMF分量建立低通滤波算法。根据滤波算法的相似度与光滑度,构造目标函数并计算最优解,其对应的滤波算法模型即为爆破振动信号的最优降噪光滑模型。通过构造仿真信号验证了降噪光滑模型算法的可行性,并将模型应用了实际露天深孔爆破振动信号的研究。采用信噪比和均方根误差两种指标对比经验模态分解(EMD)方法、小波阈值法、CEEMD-小波阈值法与滤波算法模型BP3的降噪效果,验证了降噪光滑模型在对露天矿山爆破振动信号降噪方面的有效性,并通过频谱分析进一步验证了降噪光滑模型较CEEMD-小波阈值法的优越性。结果表明:基于CEEMD的露天深孔爆破振动信号降噪光滑模型具有良好的降噪能力,能够在保留原始爆破振动信号真实特征信息的前提下对信号进行降噪,且降噪效果优于EMD方法、小波阈值法和CEEMD-小波阈值法。

关键词：露天深孔爆破振动信号 CEEMD 低通滤波降噪光滑模型

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性发育异常的基因诊断现状和研究进展

生殖医学杂志 2024年第8期33卷 1125-1131页

作者：丁蕾蕾田秦杰中国医学科学院北京协和医学院北京协和医院妇产科学系妇科内分泌与生殖中心国家妇产疾病临床医学研究中心北京100730

性发育异常(DSD)是先天性改变引起的发育异常或变异,表现为性染色体、性腺或性激素性别不典型、不一致。DSD是一类临床表现类似的遗传性疾病,临床误诊率极高。通过基因检测能够明确病因,避免因血清化验、影像检查的局限性导致疾病误诊... 详细信息

性发育异常(DSD)是先天性改变引起的发育异常或变异,表现为性染色体、性腺或性激素性别不典型、不一致。DSD是一类临床表现类似的遗传性疾病,临床误诊率极高。通过基因检测能够明确病因,避免因血清化验、影像检查的局限性导致疾病误诊。本文对性发育的胚胎学和遗传学机制进行了描述,总结了近年来DSD不同疾病中的主要基因组发现,以期为DSD的临床诊断和遗传咨询提供更多参考。

关键词：性发育异常性腺分化与发育基因检测

基于PDCA模式下的高校绩效评价体系研究——以S大学为例

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教育财会研究 2024年第3期35卷 30-36页

作者：杜俊萍王舟田洁山西大学计划财务处山西太原030006

高校绩效管理是学校财务管理的核心内容,而绩效预算评价作为绩效管理的重要组成部分,备受关注。本文将PDCA管理模式引入高校绩效管理框架,融合高校特色,构建科学合理的多维度预算绩效评价体系,助力高校绩效管理目标的实现,促进高校内涵... 详细信息

高校绩效管理是学校财务管理的核心内容,而绩效预算评价作为绩效管理的重要组成部分,备受关注。本文将PDCA管理模式引入高校绩效管理框架,融合高校特色,构建科学合理的多维度预算绩效评价体系,助力高校绩效管理目标的实现,促进高校内涵式发展,最终形成绩效计划制定、绩效目标实施、绩效考核评估及绩效反馈与应用的良性循环。同时,本文选取了S大学2018-2022年绩效评价数据及相关财务数据,基于PDCA管理模式,运用层次分析法开展预算绩效评价,旨在为高校预算绩效评价指标的建立提供有效借鉴,促进高校实现内涵式发展。

关键词：高校绩效管理绩效评价体系 PDCA模式

Modal Analysis of Axial Compressor Tip Rotating Instability under Varying Operating Conditions

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Journal of Thermal Science 2023年第4期32卷 1345-1356页

作者： LI Tao WU Yadong tian jie OUYANG Hua School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China Engineering Research Centre of Gas Turbine and Civil Aero Engine Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China

The full annulus numerical research was performed on a low-speed compressor rotor to investigate the rotating instability in the tip *** frequency spectra show the existence of rotating instability at narrow stable operating *** the decrease of flow rate,31 cells of flow disturbance can be found in the instantaneous flow *** distribution of vortex suggests that the circumferential propagation of the interaction between tip leakage vortex and adjacent blade brings about these *** dynamic mode decomposition(DMD)method and spatial discrete Fourier transform(SDFT)were applied to obtain the circumferential mode features,and the results indicate that the rotating instability is associated with the 31 cells of flow *** the DMD method was further applied on the pressure data from a circle and an annulus domain,so as to extract different mode components with the corresponding spatial structures,frequencies and *** results suggest that DMD modes can display the flow feature and explore the evolution of each instability source in the tip flow field.

关键词： axial compressor rotating instability flow structure circumferential mode dynamic mode decomposition

In situ observations of soil hydraulic properties and soil moisture in a high,cold mountainous area of the northeastern Qinghai-Tibet Plateau

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Science China Earth Sciences 2023年第8期66卷 1757-1775页

作者： jie tian Baoqing ZHANG Xuejin WANG Chansheng HE Key Laboratory of West China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Department of Geography Environmentand TourismWestern Michigan UniversityKalamazooMichigan 49009USA Dayekou Hydrological Process Observation and Research Station Lanzhou UniversityLanzhou 730000China

Information on soil hydraulic properties(SHPs)and soil moisture(SM)is essential to understand and model water and energy cycles at terrestrial ***,information regarding these soil properties in existing datasets is often scarce and inaccurate for high,cold mountainous areas such as the Qinghai-Tibet Plateau(QTP).To help bridge this gap,we have compiled an SHP and SM dataset for the northeastern QTP(a major high,cold mountainous area)using measurements of soil collected at 5 and 25 cm depths from 206 sampling sites,and in-situ observations from 32 SM monitoring stations at 5,15,25,40,and 60 cm *** used this dataset to explore large-scale variations(spatial and temporal)in SHPs and SM across the study *** also evaluated several widely used SHP(soil texture,bulk density,and saturated hydraulic conductivity)and SM datasets derived by remote-sensing methods,reanalysis and data *** datasets showed that SM significantly decreases from the southeastern part to the northwestern part in the study area,and SM decreases with increases in depth over 0–70 ***,the regional annual SM showed decreased trend from 2014 to 2020 in the study ***,we detected substantial bias in the currently available large SHP datasets,which do not capture the spatial variability recorded in the in-situ ***,clay and sand estimates from both HWSD and SoilGrid datasets were significantly overestimated,and silt was significantly underestimated within the depth of 0–30 cm in the study *** also found that SM values derived from remote sensing datasets fitted the in-situ SM observations better than those derived from the reanalysis data(which had higher bias)and data assimilation(which did not capture the temporal variability of SM).Our findings emphasize the unneglectable bias of the widely-used large-scale SHP datasets,especially for the soil texture ***,an urgent need for large-scale field sampling of SHP in mountainous

关键词： Mountainous areas Soil hydraulic properties Soil moisture Soil property datasets Soil moisture datasets

改性金属有机框架对甲基苯丙胺吸附及机理分析

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工业水处理 2024年第7期44卷 96-104页

作者：宋凤娇刘正宏曹淑瑞田洁游嘉德张磊重庆医科大学药学院重庆400016 西南政法大学司法鉴定中心重庆401120 西南政法大学刑事侦查学院重庆401120 重庆生产力促进中心重庆401147

将低共熔溶剂(DES)接枝到金属有机框架ZIF/磁性还原氧化石墨烯(MG)制备了一种复合吸附剂(DES@ZIF@MG),用于吸附水中甲基苯丙胺。采用SEM、FT-IR、BET、VSM、TGA等表征研究复合材料的微观形貌及理化性质。通过吸附动力学、吸附等温线以... 详细信息

将低共熔溶剂(DES)接枝到金属有机框架ZIF/磁性还原氧化石墨烯(MG)制备了一种复合吸附剂(DES@ZIF@MG),用于吸附水中甲基苯丙胺。采用SEM、FT-IR、BET、VSM、TGA等表征研究复合材料的微观形貌及理化性质。通过吸附动力学、吸附等温线以及吸附影响实验(pH、离子浓度和腐殖酸)探究吸附剂对甲基苯丙胺的吸附性能及机理。结果表明:吸附剂DES@ZIF@MG对甲基苯丙胺的吸附符合准二级动力学模型和Langmuir等温模型,说明吸附过程是以化学吸附为主导的能量均匀吸附。结合XPS表征进一步分析,DES@ZIF@MG对甲基苯丙胺的吸附过程中主要存在氢键作用、π-π作用、静电作用以及螯合作用。

关键词：吸附低共熔溶剂金属有机框架甲基苯丙胺

钙改性虾壳生物炭处理高磷溶液后对铀的去除影响

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有色金属工程 2024年第7期14卷 163-172页

作者：肖权津田婕罗旭贺珊谭杨奕王国华南华大学土木工程学院湖南衡阳421001 南华大学污染控制与资源化技术湖南省高校重点实验室湖南衡阳421001 南华大学铀矿冶生物技术国防重点学科实验室湖南衡阳421001

通过钙改性虾壳生物炭(Ca-SBC)处理高浓度磷溶液制备了富磷-钙改性虾壳生物炭(P-Ca-SBC),探讨了钙改性虾壳生物炭处理高浓度磷后对于铀去除的影响。结果表明,在pH=3时,P-Ca-SBC对U(Ⅵ)的去除能力最高,其平衡吸附能力达到969.768 mg/g,是... 详细信息

通过钙改性虾壳生物炭(Ca-SBC)处理高浓度磷溶液制备了富磷-钙改性虾壳生物炭(P-Ca-SBC),探讨了钙改性虾壳生物炭处理高浓度磷后对于铀去除的影响。结果表明,在pH=3时,P-Ca-SBC对U(Ⅵ)的去除能力最高,其平衡吸附能力达到969.768 mg/g,是Ca-SBC的三倍。BET结果显示,较于Ca-SBC,P-Ca-SBC比表面积增加了16倍以上,孔体积增加了14倍以上。XRD、FTIR结果表明,Ca-SBC在300 mg/L的高浓度磷溶液中形成了HAP。P-Ca-SBC表面的HAP对U(Ⅵ)的吸附起着至关重要的作用。在与U(Ⅵ)接触后,在P-Ca-SBC表面的官能团与U(Ⅵ)络合,磷酸与U(Ⅵ)反应生成沉淀Ca(UO_(2))_(2)(PO_(4))_(2)·6H_(2)O。总之,在高磷浓度溶液中回收的钙改性废弃虾壳生物炭可以作为去除U(Ⅵ)有效方法。

关键词：钙改性生物炭 U(Ⅵ) 高浓度磷

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Deep reinforcement learning-based resource allocation for D2D communications in heterogeneous cellular networks

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Digital Communications and Networks 2022年第5期8卷 834-842页

作者： Yuan Zhi jie tian Xiaofang Deng Jingping Qiao Dianjie Lu School of Information Science and Engineering Shandong Normal UniversityJinan250358China School of Information and Communication Guilin University of Electronic TechnologyGuilin541004China

Device-to-Device(D2D)communication-enabled Heterogeneous Cellular Networks(HCNs)have been a promising technology for satisfying the growing demands of smart mobile devices in fifth-generation mobile *** introduction of Millimeter Wave(mm-wave)communications into D2D-enabled HCNs allows higher system capacity and user data rates to be ***,interference among cellular and D2D links remains severe due to spectrum *** this paper,to guarantee user Quality of Service(QoS)requirements and effectively manage the interference among users,we focus on investigating the joint optimization problem of mode selection and channel allocation in D2D-enabled HCNs with mm-wave and cellular *** optimization problem is formulated as the maximization of the system sum-rate under QoS constraints of both cellular and D2D users in *** solve it,a distributed multiagent deep Q-network algorithm is proposed,where the reward function is redefined according to the optimization *** addition,to reduce signaling overhead,a partial information sharing strategy that does not observe global information is proposed for D2D agents to select the optimal mode and channel through *** results illustrate that the proposed joint optimization algorithm possesses good convergence and achieves better system performance compared with other existing schemes.

关键词： Deep reinforcement learning Heterogeneous cellular networks Device-to-device communication Millimeter wave communication Resource allocation