检索结果-南通市图书馆

Numerical Solutions of the Electromagnetic Scattering by Overfilled Cavities with Inhomogeneous Anisotropic Media

在线全文

学校读者我要写书评

暂无评论

Communications in Computational Physics 2023年第7期34卷 530-562页

作者： Meiling Zhao jiahui he Liqun Wang Department of Mathematics and Physics North China Electric Power UniversityBaoding071003China hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding071003China Department of Mathematics College of ScienceChina University of PetroleumBeijing102249China Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of PetroleumBeijing102249China

In this paper,the electromagnetic scattering from overfilled cavities with inhomogeneous anisotropic media is *** solve the scattering problem,a Petrov-Galerkin finite element interfacemethod on non-body-fitted grids is *** reduce the infinite domain of scattering to a bounded domain problem by introducing a transparent boundary *** level set function is used to capture complex boundary and interface geometry that is not aligned with the ***-fitted grids allow us to save computational costs during mesh generation and significantly reduce the amount of computer memory *** solution is built by connecting two linear polynomials across the interfaces to satisfy the jump *** proposed method can handle matrix coefficients produced by permittivity and permeability tensors of anisotropic *** final linear system is sparse,making it more suitable for most iterative *** experiments show that the proposed method has good convergence and ***,we discover that the absorbing properties of anisotropic media clearly and positively influence the reduction of radar cross *** has also been demonstrated that the method can achieve second-order accuracy.

关键词： Electromagnetic scattering overfilled cavity inhomogeneous anisotropicmedia nonbody-fitted grids Petrov-Galerkin finite element interface method

Review of accumulative failure of winding insulation subjected to repetitive impulse voltages

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2019年第1期4卷 1-11页

作者： Potao Sun Wenxia Sima Xiongwei Jiang Dingfei Zhang jiahui he Lian Ye State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400030People's Republic of China Department of Materials Science College of Engineering MaterialsChongqing UniversityChongqing 400030People's Republic of China Department of Electrical and Computer Engineering University of FloridaGainesvilleFL 32611USA

The premature failure phenomenon that occurs in solid insulation under the application of repetitive impulse voltages is known as the accumulative effect of impulse voltages on a solid *** accumulative failure of winding insulation is considered to be a core problem resulting from this *** main problems include the accumulative failure of motor winding insulation under pulse-width modulation impulses and the accumulative failure of transformer winding insulation under the application of overvoltages,and these problems represent new challenges in the safe and stable operation of power *** regards to the above problems,this study reviews the results of recent research on the accumulative failure characteristics and mechanisms of winding insulation when subjected to repetitive impulse *** challenges faced are discussed at the end of this study.

关键词： insulation winding dielectric

人脐带间充质干细胞来源外泌体抗小鼠肾缺血再灌注损伤的机制

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国组织工程研究 2025年第13期29卷 2706-2712页

作者：李灵玉魏华锋罗豪王浩贺佳辉姚雅韡吕兴华兰州大学第一临床医学院甘肃省兰州市730000 兰州大学第一医院日间手术中心甘肃省兰州市730000

背景:人脐带间充质干细胞来源外泌体参与多种损伤修复过程,其对肾缺血再灌注损伤的影响以及具体机制还没有完全阐明。目的:探讨人脐带间充质干细胞来源外泌体治疗肾缺血再灌注损伤的分子机制。方法:①培养人脐带间充质干细胞,使用外泌... 详细信息

背景:人脐带间充质干细胞来源外泌体参与多种损伤修复过程,其对肾缺血再灌注损伤的影响以及具体机制还没有完全阐明。目的:探讨人脐带间充质干细胞来源外泌体治疗肾缺血再灌注损伤的分子机制。方法:①培养人脐带间充质干细胞,使用外泌体提取试剂盒获取外泌体并鉴定;②采用活体荧光成像技术检测外泌体在肾缺血再灌注损伤小鼠肾脏中的分布;③C57/BL6雄性小鼠30只,按随机数字表法分为5组:假手术组、肾缺血再灌注组、假手术组+Compound C组、肾缺血再灌注+外泌体组、肾缺血再灌注+外泌体+Compound C组,每组6只。除假手术组外,其余组均夹闭双侧肾蒂45 min,再灌注24 h建立肾缺血再灌注小鼠模型;假手术组+Compound C组和外泌体+Compound C组于造模前30 min腹腔注射AMPK抑制剂Compound C;外泌体组和外泌体+Compound C组在肾蒂夹闭前15 min经尾静脉注射外泌体。再灌注24 h检测各组小鼠血清肌酐和尿素氮水平、肾组织白细胞介素6和肿瘤坏死因子α水平、肾组织凋亡相关因子的表达。结果与结论:①人脐带间充质干细胞外泌体具有典型的茶托形态,直径分布在40-160 nm范围内,表达外泌体表面特异性标志膜蛋白;②与假手术组相比,肾缺血再灌注损伤小鼠肾脏更易聚集人脐带间充质干细胞外泌体;③外泌体预处理可减轻肾缺血再灌注小鼠肾损伤,降低肾小管上皮细胞凋亡水平,并且这种保护作用可被AMPK抑制剂所逆转。结果表明,人脐带间充质干细胞来源外泌体发挥肾缺血再灌注损伤的保护作用可能与激活AMPK/YAP1通路抗细胞凋亡有关。

关键词：人脐带间充质干细胞外泌体 AMPK-YAP1通路凋亡肾缺血再灌注损伤

Injectable Self‑healing Adhesive pH‑Responsive Hydrogels Accelerate Gastric hemostasis and Wound healing

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2021年第5期13卷 118-134页

作者： jiahui he Zixi Zhang Yutong Yang Fenggang Ren Jipeng Li Shaojun Zhu Feng Ma Rongqian Wu Yi Lv Gang he Baolin Guo Dake Chu Department of Gastroenterology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anPeople’s Republic of China Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research College of StomatologyXi’an Jiaotong UniversityXi’an 710049People’s Republic of China Department of Dermatology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China National Local Joint Engineering Research Center for Precision Surgery and Regenerative Medicine and Surgical Engineering Research Center of Shaanxi Province First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anPeople’s Republic of China Department of Experimental Surgery Xijing HospitalFourth Military Medical UniversityXi’anPeople’s Republic of China Department of Pathology Tangdu HospitalFourth Military Medical UniversityXi’anPeople’s Republic of China

Endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)are well-established therapeutics for gastrointestinal neoplasias,but complications after EMR/ESD,including bleeding and perforation,result in additional treatment morbidity and even threaten the lives of ***,designing biomaterials to treat gastric bleeding and wound healing after endoscopic treatment is highly desired and remains a ***,a series of injectable pH-responsive selfhealing adhesive hydrogels based on acryloyl-6-aminocaproic acid(AA)and AA-g-N-hydroxysuccinimide(AA-NHS)were developed,and their great potential as endoscopic sprayable bioadhesive materials to efficiently stop hemorrhage and promote the wound healing process was further demonstrated in a swine gastric hemorrhage/wound *** hydrogels showed a suitable gelation time,an autonomous and efficient self-healing capacity,hemostatic properties,and good *** the introduction of AA-NHS as a micro-cross-linker,the hydrogels exhibited enhanced adhesive strength.A swine gastric hemorrhage in vivo model demonstrated that the hydrogels showed good hemostatic performance by stopping acute arterial bleeding and preventing delayed bleeding.A gastric wound model indicated that the hydrogels showed excellent treatment effects with significantly enhanced wound healing with type I collagen deposition,α-SMA expression,and blood vessel *** injectable self-healing adhesive hydrogels exhibited great potential to treat gastric wounds after endoscopic treatment.

关键词： Injectable self-healing hydrogel Adhesive hydrogel Gastric hemostasis Gastric wound healing Endoscopic treatment

Emergency membrane contactor based absorption system for ammonia leaks in water treatment plants

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2008年第10期20卷 1189-1194页

作者： SHAO jiahui, FANG Xuliang, he Yiliang, JIN Qiang School of Environmental Science and Engineering, Shanghai Jiao Tong Univerisity, 800 Dongchuan Road, Shanghai 200240, China [a]School of Environmental Science Engineering Shanghai Jiao Tong Univerisity 800 Dongchuan Road Shanghai 200240 China

Because of the suspected health risks of trihalomethanes (THMs), more and more water treatment plants have replaced traditional chlorine disinfection process with chloramines but often without the proper absorption system installed in the case of ammonia leaks in the storage room. A pilot plant membrane absorption system was developed and installed in a water treatment plant for this purpose. Experimentally determined contact angle, surface tension, and corrosion tests indicated that the sulfuric acid was the proper choice as the absorbent for leaking ammonia using polypropylene hollow fiber membrane contactor. Effects of several operating conditions on the mass transfer coeffcient, ammonia absorption, and removal effciency were examined, including the liquid concentration, liquid velocity, and feed gas concentration. Under the operation conditions investigated, the gas absorption effciency over 99.9% was achieved. This indicated that the designed pilot plant membrane absorption system was effective to absorb the leaking ammonia in the model storage room. The removal rate of the ammonia in the model storage room was also experimentally and theoretically found to be primarily determined by the ammonia suction flow rate from the ammonia storage room to the membrane contactor. The ammonia removal rate of 99.9% was expected to be achieved within 1.3 h at the ammonia gas flow rate of 500 m3/h. The success of the pilot plant membrane absorption system developed in this study illustrated the potential of this technology for ammonia leaks in water treatment plant, also paved the way towards a larger scale application.

关键词： membrane contactor polypropylene hollow fiber ammonia absorption water treatment plants

Miniaturization of mechanical actuators in skin-integrated electronics for haptic interfaces

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2021年第5期7卷 31-39页

作者： Dengfeng Li jiahui he Zhen Song Kuanming Yao Mengge Wu Haoran Fu Yiming Liu Zhan Gao Jingkun Zhou Lei Wei Zhengyou Zhang Yuan Dai Zhaoqian Xie Xinge Yu Department of Biomedical Engineering City University of Hong KongHong Kong SARChina Hong Kong Centre for Cerebro-Cardiovascular health Engineering(COChe) Hong Kong SARChina State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsDalian University of TechnologyDalianChina lnstitute of Flexible Electronic Technology of Tsinghua JiaxingChina Tencent Robotics X ShenzhenChina Ningbo Institute of Dalian University of Technology NingboChina

Skin-integrated electronics,also known as electronic skin(e-skin);are rapidly developing and are gradually being adopted in biomedical fields as well as in our daily lives.E-skin capable of providing sensitive and high-resolution tactile sensations and haptic feedback to the human body would open a new e-skin paradigm for closed-loop human-machine ***,we report a class of materials and mechanical designs for the miniaturization of mechanical actuators and strategies for their integration into thin,soft e-skin for haptic *** mechanical actuators exhibit small dimensions of 5 mm diameter and 1.45 mm thickness and work in an electromagnetically driven vibrotactile mode with resonance frequency overlapping the most sensitive frequency of human *** mini actuators can be integrated simultaneously in a small area of 2 cm×2 cm to form a 3×3 haptic feedback array,which is small and compact enough to mount on a thumb ***,the thin,soft haptic interface exhibits good mechanical properties that work properly during stretching,bending,and twisting and therefore can conformally fit onto various parts of the human body to afford programmable tactile enhancement and Braille recognition with an accuracy rate over 85%.

关键词： stretching properly mount

Determination of Content of Hyperin and Luteolin in Vernonia cinerea (L.) Less.

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Medicinal Plant 2021年第1期12卷 59-62页

作者： Zhiying WEI jiahui he Hailin LU Guangxi University of Chinese Medicine Nanning 530200China

[Objectives]To determine the content of hyperin and luteolin in Vernonia cinerea(L.)Less.,and to provide basic experimental data for experimental research and clinical application of ***(L.)Less.[Methods]The components to be determined were extracted by ultrasonic extraction,and the hyperin and luteolin in ***(L.)*** separated and determined by reversed-phase high performance liquid chromatography(chromatographic conditions:reverse C 18 column,methanol-0.4%phosphoric acid as mobile phase for gradient elution,flow rate of 1.0 mL/min,detector wavelength of 360 nm).[Results]The precision and repeatability of the experimental method were good,and the solution of ***(L.)*** stable within 18 *** was a good linear relationship between the injection volume of hyperin and luteolin and the chromatographic peak area within the prescribed range,and the recovery rate was *** content of hyperin and luteolin in ***(L.)*** 0.0665 mg/g(n=3)and 0.1004 mg/g(n=3),respectively.[Conclusions]The experimental method is sensitive,specific,stable,accurate and reliable,and can be used for the determination of hyperin and luteolin in ***(L.)Less.

关键词： Vernonia cinerea(L.)Less. Hyperin Luteolin

Multi-Label Chinese Comments Categorization: Comparison of Multi-Label Learning Algorithms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of New Media 2019年第2期1卷 51-61页

作者： jiahui he Chaozhi Wang Hongyu Wu Leiming Yan Christian Lu School of Computer and Software Nanjing University of Information Science&TechnologyNanjing210044China School of Information Technology Deakin UniversityVictoriaAustralia

Multi-label text categorization refers to the problem of categorizing text througha multi-label learning algorithm. Text classification for Asian languages such as Chinese isdifferent from work for other languages such as English which use spaces to separate *** classifying text, it is necessary to perform a word segmentation operation to converta continuous language into a list of separate words and then convert it into a vector of acertain dimension. Generally, multi-label learning algorithms can be divided into twocategories, problem transformation methods and adapted algorithms. This work will usecustomer's comments about some hotels as a training data set, which contains labels for allaspects of the hotel evaluation, aiming to analyze and compare the performance of variousmulti-label learning algorithms on Chinese text classification. The experiment involves threebasic methods of problem transformation methods: Support Vector Machine, Random Forest,k-Nearest-Neighbor;and one adapted algorithm of Convolutional Neural Network. Theexperimental results show that the Support Vector Machine has better performance.

关键词： Multi-label classification Chinese text classification problem transformation,adapted algorithms

联合字典学习与OCSVM的遥测数据异常检测方法

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

航空学报 2023年第13期44卷 202-214页

作者：何家辉程志君郭波国防科技大学系统工程学院长沙410073

针对航天器遥测数据故障样本少,多参数关联异常缺乏有效检测手段的问题,引入字典学习(DL)改进一类支持向量机(OCSVM)对多参数关联关系异常的识别性能,并提出一种联合优化学习机制,以提升模型的检测效果和泛化能力。首先基于正常遥测数据... 详细信息

针对航天器遥测数据故障样本少,多参数关联异常缺乏有效检测手段的问题,引入字典学习(DL)改进一类支持向量机(OCSVM)对多参数关联关系异常的识别性能,并提出一种联合优化学习机制,以提升模型的检测效果和泛化能力。首先基于正常遥测数据,构建字典学习与OCSVM的联合学习函数,通过迭代优化的方法获取最优关联关系特征提取字典和异常决策边界;然后测试样本在最优字典下稀疏分解,提取特征输入优化后的OCSVM;最终基于异常决策边界实现异常标记。将所提方法应用于NASA公布的航天器MSL数据集和某卫星天线遥测数据进行验证,结果表明:相比于现有的一类分类异常检测方法,该方法在异常检测率、F1分数和G-mean等性能指标都有所提升,特别是在关联关系异常检测上展现出更优越的性能。

关键词：字典学习一类支持向量机遥测数据异常检测联合优化