检索结果-南通市图书馆

Characteristics of the crack tip field in high-speed railway tunnel linings under train-induced aerodynamic shockwaves

引用

Underground Space 2024年第5期18卷 199-217页

作者： Yi-Kang Liu Yu-Ling Wang e Deng Yi-Qing Ni wei-Chao Yang Wai-Kei Ao School of Civil engineering Central South UniversityChangsha 410075China National Rail Transit electrification and Automation engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityHong Kong 999077China Department of Civil and environmental engineering The Hong Kong Polytechnic UniversityHong Kong 999077China The Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057China National engineering Research Center of High-speed Railway Construction Technology Changsha 410075China

High-speed railway tunnels in various countries have continuously reported accidents of vault falling concrete *** the concrete block falling occurs,serious consequences follow,and traffic safety may be *** aerodynamic shockwave evolves from the initial compression wave may be an important inducement causing the tunnel lining cracks to grow and form falling concrete blocks.A joint calculation framework is established based on ANSYS Fluent,ABAQUS,and FRANC3D for calculating the crack tip field under the aerodynamic *** intensification effect of aerodynamic shockwaves in the crack is revealed,and the evolution characteristics of the crack tip field and the influence factors of stress intensity factor(SIF)are *** show that(1)the aerodynamic shockwave intensifies after entering the crack,resulting in more significant pressure in the crack than the input *** maximum pressure of the inclined and longitudinal cracks is higher than the corresponding values of the circumferential crack,respectively.(2)The maximum SIF of the circumferential,inclined,and longitudinal crack appears at 0.5,0.68,and 0.78 times the crack front *** maximum SIF of the circumferential crack is higher than that of the inclined and longitudinal *** possibility of crack growth of the circumferential crack is the highest under aerodynamic shockwaves.(3)The influence of train speed on the SIF of the circumferential crack is more than 40%.When the train speed,crack depth,and crack length change,the change of pressure in the crack is the direct cause of the change of SIF.

关键词： Falling concrete blocks Tunnel lining cracks Aerodynamic shockwave Intensification effect Crack tip field Stress intensity factor

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

3D Printed Polyimide/Silica Composite Aerogels for Customizable Thermal Insulation from-50℃ to 1300℃

引用

Chinese Journal of Polymer Science 2024年第7期42卷 936-945,I0007页

作者： Dingyi Yu Tiantian Xue Zhuocheng Ma Zaiyin Hu Lijuan Long Yue-e Miao wei Fan Tianxi Liu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi214122China Guizhou Aerospace Wujiang electro-Mechanical equipment Co. Ltd.Zunyi563000China School of Materials and Architectural engineering Guizhou Normal UniversityGuiyang550025China

Aerogels are widely used as thermal insulation materials because of their high porosity and low bulk ***,the insulation performance of aerogels is limited to a narrow temperature ***,the preparation of aerogel materials with precisely controlled and complex architectures is still ***,we report 3D printed polyimide/silica aerogel particle(PI/SAP)composite aerogels for thermal insulation in a wide range of temperature with customized *** printability and shape fidelity of 3D printed composite aerogels is improved by adding hydrophilic SAP as a rheology *** resulting PI/SAP composite aerogel exhibits excellent flame-retardant properties and thermal insulation from-50℃ to 1300℃.Moreover,the PI/SAP composite aerogel with customized shape can be applied for battery insulation at subzero temperatures,promising to be used as customizable and stable insulating materials in a variety of complex and extreme applications.

关键词： 3D printing Polyimide Aerogel Silica Thermal insulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

electronic property and topological phase transition in a graphene/CoBr_(2) heterostructure

引用

Chinese Physics B 2024年第2期33卷 498-505页

作者：秦元秀李胜世纪维霄张昌文 School of Physics and Technology Institute of SpintronicsUniversity of JinanJinan 250022China

Recently,significant experimental advancements in achieving topological phases have been reported in van der Waals(vdW)heterostructures involving ***,using first-principles calculations,we investigate graphene/CoBr_(2)(Gr/CoBr_(2))heterostructures and find that an enhancement of in-plane magnetic anisotropy(IMA)energy in monolayer CoBr_(2) can be accomplished by reducing the interlayer distance of the vdW *** addition,we clarify that the enhancement of IMA energy primarily results from two factors:one is the weakness of the Co-d_(xy) and Co-d_(x^(2)-y^(2)) orbital hybridization and the other is the augmentation of the Co-d_(yz) and Co-d_(z)2 orbital ***,calculation results suggest that the Kosterlitz–Thouless phase transition temperature(TKT)of a 2D XY magnet Gr/CoBr_(2)(23.8 K)is higher than that of a 2D XY monolayer CoBr_(2)(1.35 K).By decreasing the interlayer distances,the proximity effect is more pronounced and band splitting ***,by taking into account spin–orbit coupling,a band gap of approximately 14.3 meV and the quantum anomalous Hall effect(QAHe)are attained by decreasing the interlayer distance by 1.0 *** by the above conclusions,we design a topological field transistor device *** results support that the vdW interlayer distance can be used to modulate the IMA energy and QAHe of materials,providing a pathway for the development of new low-power spintronic devices.

关键词： van der Waals heterostructure in-plane magnetic anisotropy energy quantum anomalous Hall effect

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Unveiling the secrets of gastrointestinal mucous adenocarcinoma survival after surgery with artificial intelligence:A population-based study

引用

World Journal of Gastrointestinal Oncology 2024年第6期16卷 2404-2418页

作者： Jie Song Xiang-xiu Yan Fang-Liang Zhang Yong-Yi Lei Zi-Yin Ke Fang Li Kai Zhang Yu-Qi He wei Li Chao Li Yuan-Ming Pan Department of Gastroenterology Dongying People’s HospitalDongying Hospital of Shandong Provincial Hospital GroupDongying 257000Shandong ProvinceChina Gastrointestinal Surgery Department Suining Central HospitalSuining 629000Sichuan ProvinceChina Obstetrical Department Suining Central HospitalSuining 629000Sichuan ProvinceChina School of Medicine Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107Guangdong ProvinceChina Department of Pathology Aerospace Center HospitalPeking University Aerospace School of Clinical MedicineBeijing 100049China General Department Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China Department of Gastroenterology Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China Department of Thoracic Surgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina Department of Gastroenterology Aerospace Center HospitalPeking University Aerospace School of Clinical MedicineBeijing 100049China Cancer Research Center Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China

BACKGROUND Research on gastrointestinal mucosal adenocarcinoma(GMA)is limited and controversial,and there is no reference tool for predicting postoperative *** To investigate the prognosis of GMA and develop predictive *** From the Surveillance,epidemiology,and end Results database,we collected clinical information on patients with *** random sampling,the patients were divided into the discovery(70%of the total,for model training),validation(20%,for model evaluation),and completely blind test cohorts(10%,for further model evaluation).The main assessment metric was the area under the receiver operating characteristic curve(AUC).All collected clinical features were used for Cox proportional hazard regression analysis to determine factors influencing GMA’s *** This model had an AUC of 0.7433[95% confidence intervals(95%CI):0.7424-0.7442]in the discovery cohort,0.7244(GMA:0.7234-0.7254)in the validation cohort,and 0.7388(95%CI:0.7378-0.7398)in the test *** packaged it into Windows software for doctors’use and uploaded *** gastric adenocarcinoma had the worst prognosis,and these were protective factors of GMA:Regional nodes examined[hazard ratio(HR):0.98,95%CI:0.97-0.98,Pemotherapy(HR:0.62,95%CI:0.58-0.66,Pe deep learning-based tool developed can accurately predict the overall survival of patients with GMA *** surgery,chemotherapy,and adequate lymph node dissection during surgery can improve patient outcomes.

关键词： Deep learning Gastrointestinal mucous adenocarcinoma Overall survival Surgery Clinical tool

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

elite Dung Beetle Optimization Algorithm for Multi-UAV Cooperative Search in Mountainous environments

引用

Journal of Bionic engineering 2024年第4期21卷 1677-1694页

作者： Xiaoyong Zhang wei Yue The College of Marine electrical engineering Dalian Maritime UniversityDalian116026China

This paper aims to address the problem of multi-UAV cooperative search for multiple targets in a mountainous environment,considering the constraints of UAV dynamics and prior environmental ***,using the target probability distribution map,two strategies of information fusion and information diffusion are employed to solve the problem of environmental information inconsistency caused by different UAVs searching different areas,thereby improving the coordination of UAV ***,the task region is decomposed into several high-value sub-regions by using data clustering *** on this,a hierarchical search strategy is proposed,which allows precise or rough search in different probability areas by adjusting the altitude of the aircraft,thereby improving the search ***,the elite Dung Beetle Optimization Algorithm(eDBOA)is proposed based on bionics by accurately simulating the social behavior of dung beetles to plan paths that satisfy the UAV dynamics constraints and adapt to the mountainous terrain,where the mountain is considered as an obstacle to be ***,the objective function for path optimization is formulated by considering factors such as coverage within the task region,smoothness of the search path,and path *** effectiveness and superiority of the proposed schemes are verified by the simulation.

关键词： Mountainous environment Multi-UAV cooperative search environment information consistency elite dung beetle optimization algorithm(eDBOA) Path planning

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

引用

Journal of Systems engineering and electronics 2024年第1期35卷 24-30页

作者： TIAN Jing ZHANG wei School of Information and electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial *** the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation *** cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range *** principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deep learning to develop zero-equation based turbulence model for CFD simulations of the built environment

引用

Building Simulation 2024年第3期17卷 399-414页

作者： Giovanni Calzolari wei Liu Division of Sustainable Buildings Department of Civil and Architectural EngineeringKTH Royal Institute of TechnologyBrinnelvägen 23Stockholm11428Sweden

This study aims to improve the accuracy and speed of predictions for thermal comfort and air quality in built environments by creating a coupled framework between computational fluid dynamics(CFD)simulations and deep learning *** coupling approach is showcased by the development of a data-driven turbulence *** new turbulence model is built using a deep learning neural network,whose mapping structure is based on a zero-equation turbulence model for built environment simulations,and is coupled with the CFD software OpenFOAM to create a hybrid *** neural network is a standard shallow multi-layer *** number of hidden layers and nodes per layer was optimized using Bayesan optimization *** framework is trained on an indoor environment case study,as well as tested on an indoor office simulation and an outdoor building array *** show that the deep learning based turbulence model is more robust and faster than traditional two-equation Reynolds average Navier-Stokes(RANS)turbulence models,while maintaining a similar level of *** model also outperforms the standard algebraic zero-equation model due to its superior ability to generalize to various flow *** some challenges,namely the mapping constraint,the limited training dataset size and the source of generation of training data,the hybrid framework demonstrates the viability of the coupling technique and serves as a starting point for future development of more reliable and advanced models.

关键词： neural networks computational fluid dynamics(CFD) turbulence model OpenFOAM

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

extracellular vesicles derived from mesenchymal stem cells mediate extracellular matrix remodeling in osteoarthritis through the transport of microRNA-29a

引用

World Journal of Stem Cells 2024年第2期16卷 191-206页

作者： Fan Yang Wan-Qi Xiong Chen-Zhi Li Ming-Jian Wu xiu-Zhi Zhang Chun-Xiao Ran Zhen-Hao Li Yan Cui Bao-Yi Liu De-wei Zhao Department of Orthopedics Affiliated Zhongshan Hospital of Dalian UniversityDalian 116001Liaoning ProvinceChina

BACKGROUND Knee osteoarthritis(KOA)is a common orthopedic condition with an uncertain etiology,possibly involving genetics and *** like changes in chondrocyte microenvironment,oxidative stress,inflammation,and immune responses affect KOA ***-stage treatment options primarily target symptom *** stem cells(MSCs)show promise for treatment,despite *** research highlights microRNAs(miRNAs)within MSC-released extracellular vesicles that can potentially promote cartilage regeneration and hinder KOA *** suggests exosomes(exos)as a promising avenue for future *** these findings emphasize the need for effective KOA progression management,further safety and efficacy validation for exos is *** To explore miR-29a’s role in KOA,we’ll create miR-29a-loaded vesicles,testing for early treatment in rat *** extraction of bone marrow MSC-derived extracellular vesicles,preparation of engineered vesicles loaded with miR-29a using ultrasonication,and identification using quantitative reverse transcription polymerase chain reaction;after establi-shing a rat model of KOA,rats were randomly divided into three groups:Blank control group injected with saline,normal extracellular vesicle group injected with normal extracellular vesicle suspension,and engineered extrace-llular vesicle group injected with engineered extracellular vesicle *** three groups evaluation,histological detection,and immunohistochemical detection to compare and evaluate the progress of various forms of *** General behavioral observation results showed that the extracellular vesicle group and engineered extracellular vesicle group had better performance in all four indicators of pain,gait,joint mobility,and swelling compared to the blank control ***,the engineered extracellular vesicle group had better pain relief at 4 wk and better knee joint mobility at 8 wk compared to the nor

关键词： exosomes Osteoarthritis Mesenchymal stem cells MicroRNA-29a Intra-articular injection

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer-assisted three-dimensional individualized extreme liver resection for hepatoblastoma in proximity to the major liver vasculature

引用

World Journal of Gastrointestinal Surgery 2024年第4期16卷 1066-1077页

作者： Wen-Li xiu Jie Liu Jing-Li Zhang Jing-Miao Wang Xue-Feng Wang Fei-Fei Wang Jie Mi Xi-wei Hao NanXia Qian Dong Department of Pediatric Surgery The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina Department of Pediatric Surgery Yijishan Hospital of Wannan Medical CollegeWuhu 241000Anhui ProvinceChina Shandong Provincial Key Laboratory of Digital Medicine and Computer-assisted Surgery Shandong College Collaborative Innovation Center of Digital Medicine Clinical Treatment and Nutrition HealthQingdao UniversityQingdao 266003Shandong ProvinceChina

BACKGROUND The management of hepatoblastoma(HB)becomes challenging when the tumor remains in close proximity to the major liver vasculature(PMV)even after a full course of neoadjuvant chemotherapy(NAC).In such cases,extreme liver resection can be considered a potential *** To explore whether computer-assisted three-dimensional individualized extreme liver resection is safe and feasible for children with HB who still have PMV after a full course of *** We retrospectively collected data from children with HB who underwent surgical resection at our center from June 2013 to June *** then analyzed the detailed clinical and three-dimensional characteristics of children with HB who still had PMV after a full course of *** Sixty-seven children diagnosed with HB underwent surgical *** age at diagnosis was 21.4±18.8 months,and 40 boys and 27 girls were ***-nine(88.1%)patients had a single tumor,39(58.2%)of which was located in the right lobe of the liver.A total of 47 patients(70.1%)had PRe-TeXT III or ***-nine patients(58.2%)underwent delayed *** a full course of NAC,16 patients still had close PMV(within 1 cm in two patients,touching in 11 patients,compressing in four patients,and showing tumor thrombus in three patients).There were 6 patients of tumors in the middle lobe of the liver,and four of those patients exhibited liver anatomy *** 16 children underwent extreme liver resection after comprehensive preoperative *** procedures were performed according to the preoperative plan,and the operations were successfully ***,the 3-year event-free survival of 67 children with HB is 88%.Among the 16 children who underwent extreme liver resection,three experienced recurrence,and one died due to multiple *** extreme liver resection for HB that is still in close PMV after a full course of NAC is both safe and *** approach not only reduces th

关键词： Children Hepatoblastoma Surgery Three-dimensional Computer-assisted

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optimal retrofitting scenarios of multi-objective energy-efficient historic building under different national goals integrating energy simulation,reduced order modelling and NSGA-II algorithm

引用

Building Simulation 2024年第6期17卷 933-954页

作者： Hailu wei Yuanhao Jiao Zhe Wang wei Wang Tong Zhang School of Architecture Southeast UniversityNanjingJiangsu Province210096China Key Laboratory of Urban and Architectural Heritage Conservation(Southeast University) Ministry of EducationNanjingChina Department of Civil and environmental engineering The Hong Kong University of Science and TechnologyHong KongChina HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute FutianShenzhenChina

Retrofitting a historic building under different national goals involves multiple objectives,constraints,and numerous potential measures and packages,therefore it is time-consuming and challenging during the early design *** study introduces a systematic retrofitting approach that incorporates standard measures for the building envelope(walls,windows,roof),as well as the heating,cooling,and lighting *** retrofit objectives are delineated based on prevailing Chinese *** retrofit measures function as genes to optimize energy-savings,carbon emissions,and net present value(NPV)by employing a log-additive decomposition approach through energy simulation techniques and NSGA-II,yielding 185,163,and 8 ***,a weighted sum method is proposed to derive optimal solutions across multiple *** framework is applied to a courtyard building in Nanjing,China,and the outcomes of the implementation are scrutinized to ascertain the optimal retrofit package under various *** this retrofit,energy consumption can be diminished by up to 63.62%,resulting in an NPV growth of 151.84%,and maximum rate of 60.48%carbon *** three result values not only indicate that the optimal values are achieved in these three aspects of energy saving,carbon reduction and economy,but also show the possibility of possible equilibrium in this multi-objective optimization *** framework proposed in this study effectively addresses the multi-objective optimization challenge in building renovation by employing a reliable optimization algorithm with a computationally efficient reduced-order *** provides valuable insights and recommendations for optimizing energy retrofit strategies and meeting various performance objectives.

关键词： historic building energy-efficient retrofitting building energy simulation log-additive decomposition approach NSGA-II

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：