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Effect of the protrusion shape on gas ingestion of two sealing structures

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Chinese Journal of Aeronautics 2021年第4期34卷 320-331页

作者： Zeyu WU Xiang LUO Jianqin ZHU Hang CHEN jiahua liu School of Energy and Power Engineering Beihang UniversityBeijing 100083China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100083China

The windage loss caused by protrusion in a rotor–stator cavity has been studied in detail,and there are abundant fitting formulas that have been summarized to calculate the moment *** other theorists have emphasized its effect on the sealing efficiency,proposing that installation of protrusion could alleviate gas ***,the protrusion shape which is an influential factor on the sealing efficiency has not been focused in previous *** the experimental method of measuring CO2 volume fraction,cavity pressure,and power consumption,we investigated the effects of several typical protrusion shapes on various parameters for two sealing structures,in order to obtain the optimal *** showed that a variation of the protrusion shape had little impact on the static pressure,but the total pressure and the sealing efficiency increased in different ***,even though the hexagon shape resulted in the highest sealing efficiency,we observed that the drop shape had the best overall performance in all of the eight models,which could result in higher efficiency of the turbine *** combination of a radial seal structure and protrusion could improve sealing efficiency better.

关键词： Axial seal Cavity Gas ingestion Protrusion shape Radial seal Sealing efficiency Turbine

Clarification of underneath capacity loss for O3-type Ni, co free layered cathodes at high voltage for sodium ion batteries

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Journal of Energy Chemistry 2023年第2期77卷 479-486,I0012页

作者： Dong Zhou De Ning Jun Wang jiahua liu Gaoyuan Zhang Yinguo Xiao Jiaxin Zheng Yongli Li Jie Li Xinzhi liu Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices School of PhysicsSun Yat-sen UniversityGuangzhou 510275GuangdongChina School of Innovation and Entrepreneurship Southern University of Science and TechnologyShenzhen 518055GuangdongChina Centre for Photonics Information and Energy Materials Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhen 518055GuangdongChina Institute for Clean Energy Technology North China Electric Power UniversityBeijing 102206China Department of Energy Politecnico di MilanoVia Lambruschini 4Milano 20156Italy Centre for Physical Mechanics and Biophysics School of PhysicsSun Yat-sen UniversityGuangzhou 510275GuangdongChina

Earth abundant O3-type NaFe_(0.5)Mn_(0.5)O_(2)layered oxide is regarded as one of the most promising cathodes for sodium ion batteries due to its low cost and high energy ***,its poor structural stability and cycle life strongly impede the practical ***,the dynamic phase evolution as well as charge compensation mechanism of O3-type NaFe_(0.5)Mn_(0.5)O_(2)cathode during sodiation/desodiation are revealed by a systemic study with operando X-ray diffraction and X-ray absorption spectroscopy,high resolution neutron powder diffraction and neutron pair distribution *** layered structure experiences a phase transition of O3→P3→OP2→ramsdellite during the desodiation,and a new O3’phase is observed at the end of the discharge state(1.5 V).The density functional theory(DFT)calculations and nPDF results suggest that depletion of Na^(+)ions induces the movement of Fe into Na layer resulting the formation of an inert ramsdellite phase thus causing the loss of capacity and structural ***,the operando XAS clarified the voltage regions for active Mn^(3+)/Mn^(4+)and Fe^(3+)/Fe^(4+)redox *** work points out the universal underneath problem for Fe-based layered oxide cathodes when cycled at high voltage and highlights the importance to suppress Fe migration regarding the design of high energy O3-type cathodes for sodium ion batteries.

关键词： Sodium ion batteries Layered oxide cathode Iron migration Operando X-ray absorption spectroscopy Neutron measurements

基于隐马尔可夫模型的出租车轨迹预测方法研究

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基于隐马尔可夫模型的出租车轨迹预测方法研究

作者： liu jiahua 长安大学

学位级别：硕士

出租车作为城市公共交通的一种工具,在城市居民日常出行中发挥着重要作用。对出租车轨迹的准确预测有助于城市路网交通状态感知和预测,以及基于位置的交通信息服务。为了提升出租车轨迹预测的准确性,本文提出了一种基于Transformer模型... 详细信息

出租车作为城市公共交通的一种工具,在城市居民日常出行中发挥着重要作用。对出租车轨迹的准确预测有助于城市路网交通状态感知和预测,以及基于位置的交通信息服务。为了提升出租车轨迹预测的准确性,本文提出了一种基于Transformer模型的路段聚类方法形成对路网的层次化表达。而后,利用层次化的隐马尔可夫模型对轨迹序列中存在的空间层次关系进行建模。同时,基于路网中空间层次间的关系,提出了一种时空关系融合网络,表达局部路网与全局路网之间的关联关系,对路网中不同空间层次下的出租车轨迹进行预测。主要研究内容如下:(1)提出一种基于Transformer模型的路网聚类方法。该方法首先使用独热码对路段物理属性进行嵌入表达;其次,考虑路段嵌入属性间的全局注意力,基于Transformer模型构建K均值聚类算法,提取路段聚类簇和路段与路段聚类簇之间的隶属关系。形成以路段号表示的轨迹序列和路段聚类簇表示的轨迹序列。同时,为了精确表示车辆在路段中的位置,进一步将路段切分为子路段,形成轨迹序列的子路段表达。(2)提出了一种基于层次化隐马尔可夫模型的多层次轨迹预测方法。该方法首先构建路段聚类簇层次与路段号层次间的隐马尔可夫模型,以及路段号层次与子路段层次间的隐马尔可夫模型。其次,基于GCN、Conv2d与Self-attention构建了一种层次化的融合网络,对路段聚类簇之间的出发量关系与路段聚类簇之间的距离关系,以及路段号层次下考虑了路段拓扑关系与路段出发量关系进行融合,对路段聚类簇层次与路段号层次间的隐马尔可夫模型,以及路段号层次与子路段层次间的隐马尔可夫模型进行优化。利用优化后的层次化隐马尔可夫模型对轨迹进行层次化的预测。本文使用西安市出租车轨迹数据对所提方法进行了实验验证,实验结果表明,本文所提出的出租车轨迹预测方法优于现有的轨迹预测方法。

关键词：出租车轨迹预测隐马尔可夫模型深度学习聚类分析 GPS轨迹数据

Chemical composition， biological activities and product development of Gastrodia elata: a review

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Food Science and Human Wellness 2024年

作者： Yuchen Jiang Liankui Wen Wenqi Wang Rongchen Zhu jiahua liu Yang He Fei Zheng Yuzhu Wu Department of Food Science and Engineering， Jilin Agricultural University Jilin Ginseng Academy， Changchun University of Chinese Medicine National Engineering Research Center for Wheat and Corn Deep Processing

Gastrodia elata Blume (G. elata) has a rich history of traditional Asian use. However， there is still a need for systematic analysis regarding the relationship and in-depth development between its components and functions. Through comprehensive analysis utilizing databases such as PubMed， Web of Science， and Google Scholar， the practical components， biological activities， and product development of G. elata have been investigated. It has been found that the main active components of G. elata， such as Gastrodin and Gastrodia Polysaccharides， possess functionalities in improving conditions such as epilepsy， hypertension， and osteoporosis. These active components exhibit phenolic hydroxyl groups， molecular weight， conformation， and spatial arrangement， contributing to their enhanced ability to scavenge free radicals. Additionally， G. elata is known to have organic acids and esters， which exhibit potential immune regulatory and antiviral properties. Compounds with multiple acidic functional groups exhibit even more vigorous activity. Steroidal compounds like β-sitosterol， due to their presence of alcohol and ketone groups， along with a multi-ring structure， exhibit superior cholesterol-lowering activity. G. elata has already been recognized in the Traditional Chinese Medicine and Food Homology list， showcasing its potential for development in line with the health demands of the current era. However， challenges regarding quality evaluation， peculiar odor， and the extraction process of the practical components still require immediate attention. Constructing a robust evaluation system and optimizing product processing techniques will be crucial for the future advancement of the G. elata industry.

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Design of a highly potent GLP-1R and GCGR dual-agonist for recovering hepatic fibrosis

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Acta Pharmaceutica Sinica B 2022年第5期12卷 2443-2461页

作者： Nazi Song Hongjiao Xu jiahua liu Qian Zhao Hui Chen Zhibin Yan Runling Yang Zhiteng Luo Qi liu Jianmei Ouyang Shuohan Wu Suijia Luo Shuyin Ye Runfeng Lin Xi Sun Junqiu Xie Tian Lan Zhongdao Wu Rui Wang Xianxing Jiang School of Pharmaceutical Sciences Guangdong Provincial Key Laboratory of Chiral Molecule and Drug DiscoverySun Yat-sen UniversityGuangzhou 510006China Department of Parasitology of Zhongshan School of Medicine Sun Yat-sen UniversityGuangzhou 510006China Key Laboratory of Tropical Disease Control Ministry of EducationSun Yat-sen UniversityGuangzhou 510006China Provincial Engineering Technology Research Center for Biological Vector Control Sun Yat-sen UniversityGuangzhou 510006China Research Unit of Peptide Science Chinese Academy of Medical SciencesLanzhou 730000China Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical SciencesLanzhou UniversityLanzhou 730000China Shenzhen Turier Biotech.Co. Ltd.Shenzhen 518118China Guangdong Pharmaceutical University Guangzhou 510006China

Currently, there is still no effective curative treatment for the development of late-stage liver fibrosis. Here, we have illustrated that TB001, a dual glucagon-like peptide-1 receptor/glucagon receptor(GLP-1 R/GCGR) agonist with higher affinity towards GCGR, could retard the progression of liver fibrosis in various rodent models, with remarkable potency, selectivity, extended half-life and low toxicity. Four types of liver fibrosis animal models which were induced by CCl_(4), a-naphthyl-isothiocyanate(ANIT), bile duct ligation(BDL) and Schistosoma japonicum were used in our study. We found that TB001 treatment dose-dependently significantly attenuated liver injury and collagen accumulation in these animal models. In addition to decreased levels of extracellular matrix(ECM) accumulation during hepatic injury, activation of hepatic stellate cells was also inhibited via suppression of TGF-β expression as well as downstream Smad signaling pathways particularly in CCl_(4)-and S. japonicum-induced liver fibrosis. Moreover, TB001 attenuated liver fibrosis through blocking downstream activation of proinflammatory nuclear factor kappa B/NF-kappa-B inhibitor alpha(NFκB/IKBa) pathways as well as cJun N-terminal kinase(JNK)-dependent induction of hepatocyte apoptosis. Furthermore, GLP-1 R and/or GCGR knock-down results represented GCGR played an important role in ameliorating CCl_(4)-induced hepatic fibrosis. Therefore, TB001 can be used as a promising therapeutic candidate for the treatment of multiple causes of hepatic fibrosis demonstrated by our extensive pre-clinical evaluation of TB001.

关键词： GLP-1R GCGR Liver fibrosis Inflammation Apoptosis Candidate peptides

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建筑安全专业人才培养模式的构建与实践

中国安全科学学报 2022年第7期32卷 14-19页

作者：刘加华江苏工程职业技术学院建筑工程学院江苏南通226007 西安交通大学人居环境与建筑工程学院陕西西安710049

为提高建筑安全专业人才培养质量,探索高素质技术技能人才培养模式,结合建筑产业现代化对人才培养的新需求,分析并解决当前建筑安全专业人才培养存在的问题;以学生为主体,构建实训、实践平台,产教、产学、研训协同,实现从知识传授、技... 详细信息

为提高建筑安全专业人才培养质量,探索高素质技术技能人才培养模式,结合建筑产业现代化对人才培养的新需求,分析并解决当前建筑安全专业人才培养存在的问题;以学生为主体,构建实训、实践平台,产教、产学、研训协同,实现从知识传授、技能提升、价值塑造到引领创新的四步进阶;构建新的建筑安全专业人才培养模式,并评价其实践效果。结果表明:通过构建满足企业所需的建筑安全课程体系,培养工匠型双师团队,创新实训实践平台,产教融合、协同创新,有助于实现建筑安全专业技术技能型人才培养的增值。

关键词：建筑安全专业人才培养产教融合工匠四步进阶

Construction of Coupler Component and Numerical Atmosphere-Ocean Coupling Experiment

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通讯和计算机（中英文版） 2010年第12期7卷 1-5页

作者： Xiying liu jiahua Zhao Yijia Hu Huasheng Xia Zhong Zhong Institute of Meteorology University of Science and Technology Nanjing 211101 China

Tomato Leaf Disease Detection Algorithm Based on Yolov5s

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Tomato Leaf Disease Detection Algorithm Based on Yolov5s

预制装配式大面积非线性GRC幕墙及屋面板安装技术

第43届中国控制会议

作者： Zedong Shi jiahua liu Xubin Qin Jing Cao Tongda College of Nanjing University of Posts and Telecommunications Wuxi Branch of Jiangsu Academy of Agricultural Sciences

A modified algorithm based on YOLOv5s is proposed for tomato leaf disease detection under interference from complex environmental factors and diverse types of diseases. Firstly, multiple disease images are preprocessed to enhance the richness of the dataset. In order to enhance the image classification ability of the model, the attention mechanism is introduced in the backbone network;the C2f module of YOLOv8 replaces the original C3 module to obtain richer gradient flow information;the loss function SIoU is replaced to accelerate the convergence speed and improve the inference effect;CARAFE(ContentAware ReAssembly of FEatures) is utilized instead of the original nearest-neighbor interpolation method to expand the improved model's receptive field, obtaining more feature map information effectively, thereby enhancing detection capabilities while ensuring lightweight design. In experiments, the improved algorithm achieves a m AP0.5 of 93.3% in test validation,outperforming the main models, such as the original YOLOv5s, YOLOv8, et al. The proposed tomato leaf disease detection method maintains good detection speed and high accuracy in complex real-world scenarios. This improved algorithm meets the requirements for precision recognition, providing theoretical support for the prevention and control of tomato leaf diseases.

关键词： YOLOv5 CARAFE attention mechanism tomato leaf diseases SIoU

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施工技术 2017年第3期46卷 26-29页

作者：刘加华江苏工程职业技术学院建筑工程学院江苏南通226007 代尔夫特理工大学土木工程和地球科学学院

南京青奥会议中心幕墙及屋面板由预制装配式轻型GRC(玻璃纤维增强水泥)板安装而成,该建筑外形独特,采用不规则的非线性结构,增加了GRC板安装难度;工艺复杂,质量控制及安全文明施工难度大,对幕墙和屋面防水及保温施工要求高,采用纳米涂... 详细信息

南京青奥会议中心幕墙及屋面板由预制装配式轻型GRC(玻璃纤维增强水泥)板安装而成,该建筑外形独特,采用不规则的非线性结构,增加了GRC板安装难度;工艺复杂,质量控制及安全文明施工难度大,对幕墙和屋面防水及保温施工要求高,采用纳米涂层技术,使幕墙具有雨水自洁功能,提高了GRC板的耐久性。

关键词：预制装配式幕墙屋面板 GRC板安装施工技术