资源类型

期刊论文 309

会议视频 7

年份

2024 1

2023 17

2022 22

2021 22

2020 14

2019 17

2018 15

2017 14

2016 11

2015 17

2014 11

2013 11

2012 30

2011 25

2010 21

2009 17

2008 11

2007 9

2006 3

2005 2

展开 ︾

关键词

微地震监测 8

监测 4

变形监测 3

机器学习 3

结构健康监测 3

ANSYS 2

三峡升船机 2

三峡工程 2

优化设计 2

健康监测 2

光纤传感技术 2

台风监测 2

失效概率 2

状态监测 2

现场监测 2

裂缝 2

运载系统 2

&gamma 1

10kV高压电力电缆 1

展开 ︾

检索范围:

排序: 展示方式:

Study of high-strength CFRP bolted joints with failure- monitoring cone washers

Tsukasa KATSUMATA, Yoshihiro MIZUTANI, Akira TODOROKI, Ryosuke MATSUZAKI

《机械工程前沿(英文)》 2011年 第6卷 第3期   页码 272-276 doi: 10.1007/s11465-011-0231-1

摘要:

To increase the strength of carbon-fiber-reinforced plastic (CFRP) bolted joints, a method to increase the friction force between carbon-fiber-reinforced plastic members was proposed. The increase in failure load for the proposed joint was confirmed in finite-element method analyses and joint tests. Additionally, the feasibility of damage monitoring using surface strains of the cone washer was demonstrated.

关键词: composite     bolted joint     failure monitoring     finite-element method    

Integrated management of cardiac failure: the cardiac failure clinic

null

《医学前沿(英文)》 2011年 第5卷 第1期   页码 20-25 doi: 10.1007/s11684-011-0106-1

摘要:

The prevalence of the risk factors and the risk of cardiac failure are both increasing in China. This might be the consequence of the changes of the life conditions (emigration to the urban areas, changes in the diet and life style, lack of physical exercise, etc.). The wide range of clinical presentations of cardiac failure (acute or chronic) and of therapeutic approaches (medical or surgical) makes necessary the integration within the same structure of the various experts involved in the diagnosis and the treatment of cardiac diseases. Technologic and human resources required to offer all the options represent a multifaceted commitment which should be focused optimally in dedicated centers. In these centers, collaboration should replace competition between the medical and the surgical cardiac specialists. Development of team work should permit to optimize the cost efficacy of the treatments. Most of all, such a structure will facilitate the translation of innovative therapies between the research centers and clinical facilities.

关键词: cardiac failure     cardiac transplantation     mechanical circulatory support    

Progressive failure analysis of notched composite plate by utilizing macro mechanics approach

《结构与土木工程前沿(英文)》 2021年 第15卷 第3期   页码 623-642 doi: 10.1007/s11709-021-0726-8

摘要: In this study, gradual and sudden reduction methods were combined to simulate a progressive failure in notched composite plates using a macro mechanics approach. Using the presented method, a progressive failure is simulated based on a linear softening law prior to a catastrophic failure, and thereafter, sudden reduction methods are employed for modeling a progressive failure. This combination method significantly reduces the computational cost and is also capable of simultaneously predicting the first and last ply failures (LPFs) in composite plates. The proposed method is intended to predict the first ply failure (FPF), LPF, and dominant failure modes of carbon/epoxy and glass/epoxy notched composite plates. In addition, the effects of mechanical properties and different stacking sequences on the propagation of damage in notched composite plates were studied. The results of the presented method were compared with experimental data previously reported in the literature. By comparing the numerical and experimental data, it is revealed that the proposed method can accurately simulate the failure propagation in notched composite plates at a low computational cost.

关键词: progressive failure     notched composite plate     Hashin failure criterion     macro mechanics approach     finite element method    

以可靠性为中心的维修方法及其在隧道中的应用

王景春,房思思,李晓萌,张伟

《中国工程科学》 2017年 第19卷 第6期   页码 61-65 doi: 10.15302/J-SSCAE-2017.06.009

摘要:

本文针对目前隧道监控维修状况及存在的问题,提出以可靠性为中心的维修(RCM)作为维修理念,并将其引入到隧道管理中,对隧道设备的故障模式及可靠性进行分析,并对RCM方法在隧道监控维修中的应用做了初步研究。最后通过案例说明,隧道采用RCM方法可有效降低维修费用,具有一定的经济效益和社会效益。

关键词: 隧道     可靠性     维修     监控     故障分析    

模板辅助合成半导体金属氧化物气敏纳米材料的合理设计:综述 Research Article

关云川1,刘渝2,周可1,李强3,王团结3,李辉3

《信息与电子工程前沿(英文)》 2023年 第24卷 第7期   页码 964-979 doi: 10.1631/FITEE.2200488

摘要: 磁盘故障预测方法在单一问题上的解决方案十分成熟,例如磁盘异构问题、模型老化问题和小样本问题。然而,由于这些问题经常同时存在,只能处理其中一个问题的模型在实际预测中存在偏差。目前针对不同问题的解决方案经常相互冲突,然而现有磁盘故障预测方法通常简单地融合各种模型,缺乏在面对多个问题时对训练数据准备和学习模式的讨论。为此,提出一种多属性数据划分方法(MDP),来探索针对多个问题的训练数据准备。引入与模型无关的元学习算法(MAML),对被划分的多个数据子集进行多任务学习。基于这些改进,提出一种名为MDP-MAML的磁盘故障预测模型。MDP解决了数据不均匀划分和按时间划分的挑战,而MAML解决了针对多个问题小样本学习的问题。此外,MDP-MAML能够适应新出现的问题并进行学习和预测。在两个实际数据中心的数据集上,与最先进方法相比,MDP-MAML将曲线下面积(AUC)从0.85提升至0.89,将误检率(FDR)从0.85提升至0.91,将误报率(FAR)从4.88%降低至2.85%。

关键词: 存储系统可靠性;磁盘故障预测;自我监测、分析及报告技术(SMART);机器学习    

Bending failure performance of a shield tunnel segment based on full-scale test and numerical analysis

《结构与土木工程前沿(英文)》   页码 1033-1046 doi: 10.1007/s11709-023-0973-y

摘要: This study focuses on the bending failure performance of a shield tunnel segment. A full-scale test was conducted to investigate deformation and failure characteristics. During the loading, the bending failure process can be divided into four stages: the elastic stage, working stage with cracks, failure stage, and ultimate stage. The characteristic loads between contiguous stages are the cracking, failure, and ultimate loads. A numerical model corresponding to the test was established using the elastoplastic damage constitutive model of concrete. After a comparative analysis of the simulation and test results, parametric studies were performed to discuss the influence of the reinforcement ratio and proportion of tensile longitudinal reinforcement on the bearing capacity. The results indicated that the change in the reinforcement ratio and the proportion of tensile longitudinal reinforcement had little effect on the cracking load but significantly influenced the failure and ultimate loads of the segment. It is suggested that in the reinforcement design of the subway segment, the reinforcement ratio and the proportion of tensile longitudinal reinforcement can be chosen in the range of 0.7%–1.2% and 49%–55%, respectively, allowing the segment to effectively use the reinforcement and exert the design strength, thereby improving the bearing capacity of the segment.

关键词: shield tunnel     bearing capacity     failure mechanism     segment reinforcement    

Overview on acute-on-chronic liver failure

null

《医学前沿(英文)》 2016年 第10卷 第1期   页码 1-17 doi: 10.1007/s11684-016-0439-x

摘要:

Liver failure (LF) is defined as severe dysfunction in hepatic synthesis, detoxification, and metabolism induced by various etiologies. Clinical presentation of LF typically includes severe jaundice, coagulation disorder, hepatic encephalopathy, and ascites. LF can be classified into acute LF, acute-on-chronic LF (ACLF), and chronic LF. ACLF has been demonstrated as a distinct syndrome with unique clinical presentation and outcomes. The severity, curability, and reversibility of ACLF have attracted considerable attention. Remarkable developments in ACLF-related conception, diagnostic criteria, pathogenesis, and therapy have been achieved. However, this disease, especially its diagnostic criteria, remains controversial. In this paper, we systemically reviewed the current understanding of ACLF from its definition, etiology, pathophysiology, pathology, and clinical presentation to management by thoroughly comparing important findings between east and west countries, as well as those from other regions. We also discussed the controversies, challenges, and needs for future studies to promote the standardization and optimization of the diagnosis and treatment for ACLF.

关键词: liver failure     chronic liver failure     acute-on-chronic liver failure     diagnosis     prognosis     treatment    

Surficial stability analysis of soil slope under seepage based on a novel failure mode

《结构与土木工程前沿(英文)》 2021年 第15卷 第3期   页码 712-726 doi: 10.1007/s11709-021-0729-5

摘要: Normally, the edge effects of surficial landslides are not considered in the infinite slope method for surficial stability analysis of soil slopes. In this study, the limit stress state and discrimination equation of an infinite slope under saturated seepage flow were analyzed based on the Mohr-Coulomb strength criterion. Therefore, a novel failure mode involving three sliding zones (upper tension zone, middle shear sliding zone, and lower compression zone) was proposed. Accordingly, based on the limit equilibrium analysis, a semi-analytical framework considering the edge effect for the surficial stability of a soil slope under downslope seepage was established. Subsequently, the new failure mode was verified via a numerical finite element analysis based on the reduced strength theory with ABAQUS and some simplified methods using SLIDE software. The results obtained by the new failure mode agree well with those obtained by the numerical analysis and traditional simplified methods, and can be efficiently used to assess the surficial stability of soil slopes under rainwater seepage. Finally, an evaluation of the infinite slope method was performed using the semi-analytical method proposed in this study. The results show that the infinite slope tends to be conservative because the edge effect is neglected, particularly when the ratio of surficial slope length to depth is relatively small.

关键词: soil slope     seepage     surficial failure mode     stress state     edge effects    

LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

《结构与土木工程前沿(英文)》 2022年 第16卷 第7期   页码 871-881 doi: 10.1007/s11709-022-0863-8

摘要: The failure criteria of practical soil mass are very complex, and have significant influence on the safety factor of slope stability. The Coulomb strength criterion and the power-law failure criterion are classically simplified. Each one has limited applicability owing to the noticeable difference between calculated predictions and actual results in some cases. In the work reported here, an analysis method based on the least square support vector machine (LSSVM), a machine learning model, is purposefully provided to establish a complex nonlinear failure criterion via iteration computation based on strength test data of the soil, which is of more extensive applicability to many problems of slope stability. In particular, three evaluation indexes including coefficient of determination, mean absolute percentage error, and mean square error indicate that fitting precision of the machine learning-based failure criterion is better than those of the linear Coulomb criterion and nonlinear power-law criterion. Based on the proposed LSSVM approach to determine the failure criterion, the limit equilibrium method can be used to calculate the safety factor of three-dimensional slope stability. Analysis of results of the safety factor of two three-dimensional homogeneous slopes shows that the maximum relative errors between the proposed approach and the linear failure criterion-based method and the power-law failure criterion-based method are about 12% and 7%, respectively.

关键词: slope stability     safety factor     failure criterion     least square support vector machine    

Analysis of stress and failure in rock specimens with closed and open flaws on the surface

《结构与土木工程前沿(英文)》 2021年 第15卷 第5期   页码 1222-1237 doi: 10.1007/s11709-021-0773-1

摘要: The influence of closed and open surface flaws on the stress distribution and failure in rock specimens is investigated. Heterogeneous finite element models are developed to simulate the compression tests on flawed rock specimens. The simulated specimens include those with closed flaws and those with open flaws on the surface. Systematic analyses are conducted to investigate the influences of the flaw inclination, friction coefficient and the confining stress on failure behavior. Numerical results show significant differences in the stress, displacement, and failure behavior of the closed and open flaws when they are subjected to pure compression; however, their behaviors under shear and tensile loads are similar. According to the results, when compression is the dominant mode of stress applied to the flaw surface, an open flaw may play a destressing role in the rock and relocate the stress concentration and failure zones. The presented results in this article suggest that failure at the rock surface may be managed in a favorable manner by fabricating open flaws on the rock surface. The insights gained from this research can be helpful in managing failure at the boundaries of rock structures.

关键词: surface flaw     heterogeneity     circular hole     numerical modeling     relative displacement    

Experimental study on the progressive failure and its anchoring effect of weak-broken rock vertical slope

Hehua ZHU, Qianwei XU, Wenqi DING, Feng HUANG

《结构与土木工程前沿(英文)》 2011年 第5卷 第2期   页码 208-224 doi: 10.1007/s11709-011-0111-0

摘要: To improve the understanding on the failure behavior and its anchoring effect of weak-broken rock slope, the rock of grade IV according to China is taken as reference prototype, and a series of model tests were carried out in laboratory. These tests can be divided into two categories, that is, with bolt reinforcement and without bolt reinforcement. In which, the stability of slope reinforced with different bolt diameter, different anchor length and different space are studied. The test results show that the collapse of slope is the combination of tension failure at the top and the compression-shearing failure at the bottom of the slope, and its failure process presents progressive characteristics. The contributions of bolt reinforcement are mainly reflected by the aspects of shear resistance, crack resistance and anti-extension. The reinforcement of blot not only can improve the vertical bearing capacity before failure, but also can reduce the vertical settlement and allow greater lateral rock wall deformation; what is more, the stress concentration degree in rock mass can be dispersed, which do help to improve the stability of slope rock mass.

关键词: progressive failure     weak-broken rock     slope     model test     bolt    

Stability analysis of slopes with planar failure using variational calculus and numerical methods

Norly BELANDRIA, Roberto ÚCAR, Francisco M. LEÓN, Ferri HASSANI

《结构与土木工程前沿(英文)》 2020年 第14卷 第5期   页码 1262-1273 doi: 10.1007/s11709-020-0657-9

摘要: This study investigates the technique of variational calculus applied to estimate the slope stability considering the mechanism of planar failure. The critical plane failure surface should be determined because it theoretically indicates the most unfavorable plane to be considered when stabilizing a slope to rectify the instability generated by several statistically possible planes. This generates integrals that can be solved by numerical methods, such as the Newton Cotes and the finite differences methods. Additionally, a system of nonlinear equations is obtained and solved. The surface of the critical planar failure is determined by applying the condition of transversality in mobile boundaries, for which various examples are provided. The number of slices is varied in one of the examples, while the surface of the critical planar failure is determined in the others. Results are compared using analytical methods through axis rotations. All the results obtained by considering normal stress, safety factors, and critical planar failure are nearly the same; however, in this research, a study is carried out for “ ” number of slices using programming methods. Sub-routines are important because they can be applied in slopes with different geometry, surcharge, interstitial pressure, and pseudo-static load.

关键词: slopes stability     planar failure     variational calculus     numerical methods    

Theoretical study of failure in composite pressure vessels subjected to low-velocity impact and internal

Roham RAFIEE, Hossein RASHEDI, Shiva REZAEE

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1349-1358 doi: 10.1007/s11709-020-0650-3

摘要: A theoretical solution is aimed to be developed in this research for predicting the failure in internally pressurized composite pressure vessels exposed to low-velocity impact. Both in-plane and out-of-plane failure modes are taken into account simultaneously and thus all components of the stress and strain fields are derived. For this purpose, layer-wise theory is employed in a composite cylinder under internal pressure and low-velocity impact. Obtained stress/strain components are fed into appropriate failure criteria for investigating the occurrence of failure. In case of experiencing any in-plane failure mode, the evolution of damage is modeled using progressive damage modeling in the context of continuum damage mechanics. Namely, mechanical properties of failed ply are degraded and stress analysis is performed on the updated status of the model. In the event of delamination occurrence, the solution is terminated. The obtained results are validated with available experimental observations in open literature. It is observed that the sequence of in-plane failure and delamination varies by increasing the impact energy.

关键词: composite pressure vessel     low-velocity impact     failure     theoretical solution     progressive damage modeling    

Non-invasive continuous blood pressure monitoring: a review of current applications

null

《医学前沿(英文)》 2013年 第7卷 第1期   页码 91-101 doi: 10.1007/s11684-013-0239-5

摘要:

Blood pressure monitoring has come a long way from the initial observations made by Reverend Hales in the 18th century. There are none that deny the importance of monitoring perioperative blood pressure; however, the limited ability of the current prevalent technology (oscillometric blood pressure monitoring) to offer continuous blood pressure measurements leaves room for improvement. Invasive monitoring is able to detect beat-to-beat blood pressure measurement, but the risks inherent to the procedure make it unsuitable for routine use except when this risk is outweighed by the benefits. This review focuses on the discoveries which have led up to the current blood pressure monitoring technologies, and especially the creation of those offering non-invasive but continuous blood pressure monitoring capabilities, including their methods of measurement and limitations.

关键词: non-invasive blood pressure monitoring     continuous blood pressure monitoring     invasive blood pressure monitoring     Riva-Rocci technique     oscillometric     Pe?áz technique     arterial tonometry     pulse transit time    

Optimization of the mechanical performance and damage failure characteristics of laminated composites

《结构与土木工程前沿(英文)》   页码 1357-1369 doi: 10.1007/s11709-023-0996-4

摘要: In this study, the effect of fiber angle on the tensile load-bearing performance and damage failure characteristics of glass composite laminates was investigated experimentally, analytically, and numerically. The glass fabric in the laminate was perfectly aligned along the load direction (i.e., at 0°), offset at angles of 30° and 45°, or mixed in different directions (i.e., 0°/30° or 0°/45°). The composite laminates were fabricated using vacuum-assisted resin molding. The influence of fiber orientation angle on the mechanical properties and stiffness degradation of the laminates was studied via cyclic tensile strength tests. Furthermore, simulations have been conducted using finite element analysis and analytical approaches to evaluate the influence of fiber orientation on the mechanical performance of glass laminates. Experimental testing revealed that, although the composite laminates laid along the 0° direction exhibited the highest stiffness and strength, their structural performance deteriorated rapidly. We also determined that increasing the fiber offset angle (i.e., 30°) could optimize the mechanical properties and damage failure characteristics of glass laminates. The results of the numerical and analytical approaches demonstrated their ability to capture the mechanical behavior and damage failure modes of composite laminates with different fiber orientations, which may be used to prevent the catastrophic failures that occur in composite laminates.

关键词: fiber orientation     composite laminates     stiffness degradation     analytical approaches     finite element analysis    

标题 作者 时间 类型 操作

Study of high-strength CFRP bolted joints with failure- monitoring cone washers

Tsukasa KATSUMATA, Yoshihiro MIZUTANI, Akira TODOROKI, Ryosuke MATSUZAKI

期刊论文

Integrated management of cardiac failure: the cardiac failure clinic

null

期刊论文

Progressive failure analysis of notched composite plate by utilizing macro mechanics approach

期刊论文

以可靠性为中心的维修方法及其在隧道中的应用

王景春,房思思,李晓萌,张伟

期刊论文

模板辅助合成半导体金属氧化物气敏纳米材料的合理设计:综述

关云川1,刘渝2,周可1,李强3,王团结3,李辉3

期刊论文

Bending failure performance of a shield tunnel segment based on full-scale test and numerical analysis

期刊论文

Overview on acute-on-chronic liver failure

null

期刊论文

Surficial stability analysis of soil slope under seepage based on a novel failure mode

期刊论文

LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

期刊论文

Analysis of stress and failure in rock specimens with closed and open flaws on the surface

期刊论文

Experimental study on the progressive failure and its anchoring effect of weak-broken rock vertical slope

Hehua ZHU, Qianwei XU, Wenqi DING, Feng HUANG

期刊论文

Stability analysis of slopes with planar failure using variational calculus and numerical methods

Norly BELANDRIA, Roberto ÚCAR, Francisco M. LEÓN, Ferri HASSANI

期刊论文

Theoretical study of failure in composite pressure vessels subjected to low-velocity impact and internal

Roham RAFIEE, Hossein RASHEDI, Shiva REZAEE

期刊论文

Non-invasive continuous blood pressure monitoring: a review of current applications

null

期刊论文

Optimization of the mechanical performance and damage failure characteristics of laminated composites

期刊论文