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Liquefaction prediction using support vector machine model based on cone penetration data

Pijush SAMUI

《结构与土木工程前沿(英文)》 2013年 第7卷 第1期   页码 72-82 doi: 10.1007/s11709-013-0185-y

摘要: A support vector machine (SVM) model has been developed for the prediction of liquefaction susceptibility as a classification problem, which is an imperative task in earthquake engineering. This paper examines the potential of SVM model in prediction of liquefaction using actual field cone penetration test (CPT) data from the 1999 Chi-Chi, Taiwan earthquake. The SVM, a novel learning machine based on statistical theory, uses structural risk minimization (SRM) induction principle to minimize the error. Using cone resistance ( ) and cyclic stress ratio ( ), model has been developed for prediction of liquefaction using SVM. Further an attempt has been made to simplify the model, requiring only two parameters ( and maximum horizontal acceleration ), for prediction of liquefaction. Further, developed SVM model has been applied to different case histories available globally and the results obtained confirm the capability of SVM model. For Chi-Chi earthquake, the model predicts with accuracy of 100%, and in the case of global data, SVM model predicts with accuracy of 89%. The effect of capacity factor ( ) on number of support vector and model accuracy has also been investigated. The study shows that SVM can be used as a practical tool for prediction of liquefaction potential, based on field CPT data.

关键词: earthquake     cone penetration test     liquefaction     support vector machine (SVM)     prediction    

Prediction of the shear wave velocity

Amoroso SARA

《结构与土木工程前沿(英文)》 2014年 第8卷 第1期   页码 83-92 doi: 10.1007/s11709-013-0234-6

摘要: The paper examines the correlations to obtain rough estimates of the shear wave velocity from non-seismic dilatometer tests (DMT) and cone penetration tests (CPT). While the direct measurement of is obviously preferable, these correlations may turn out useful in various circumstances. The experimental results at six international research sites suggest that the DMT predictions of from the parameters (material index), (horizontal stress index), (constrained modulus) are more reliable and consistent than the CPT predictions from (cone resistance), presumably because of the availability, by DMT, of the stress history index .

关键词: horizontal stress index     shear wave velocity     flat dilatometer test     cone penetration test    

In situ-based assessment of soil liquefaction potential–Case study of an earth dam in Tunisia

Ikram GUETTAYA,Mohamed Ridha EL OUNI

《结构与土木工程前沿(英文)》 2014年 第8卷 第4期   页码 456-461 doi: 10.1007/s11709-014-0259-5

摘要: The present paper examines the evaluation of liquefaction potential of an earth dam foundation in Tunisia. The assessment of soil liquefaction was made using deterministic and probabilistic simplified procedures developed from several case histories. The data collected from the field investigation performed before and after the vibrocompaction are analyzed and the results are reported. The obtained results show that after vibrocompaction, a significant improvement of the soil resistance reduces the liquefaction potential of the sandy foundation. Indeed, in the untreated layers, the factor of safety drops below 1 which means that the soil is susceptible for liquefaction. However, in the compacted horizons, the values of exceed the unit which justifies the absence of liquefaction hazard of the foundation.

关键词: liquefaction     cone penetration test (CPT)     standard penetration test (SPT)     vibrcompaction     sand    

Application of machine learning algorithms for the evaluation of seismic soil liquefaction potential

Mahmood AHMAD, Xiao-Wei TANG, Jiang-Nan QIU, Feezan AHMAD, Wen-Jing GU

《结构与土木工程前沿(英文)》 2021年 第15卷 第2期   页码 490-505 doi: 10.1007/s11709-020-0669-5

摘要: This study investigates the performance of four machine learning (ML) algorithms to evaluate the earthquake-induced liquefaction potential of soil based on the cone penetration test field case history records using the Bayesian belief network (BBN) learning software Netica. The BBN structures that were developed by ML algorithms-K2, hill climbing (HC), tree augmented naive (TAN) Bayes, and Tabu search were adopted to perform parameter learning in Netica, thereby fixing the BBN models. The performance measure indexes, namely, overall accuracy ( ), precision, recall, , and area under the receiver operating characteristic curve, were used to evaluate the training and testing BBN models’ performance and highlight the capability of the K2 and TAN Bayes models over the Tabu search and HC models. The sensitivity analysis results showed that the cone tip resistance and vertical effective stress are the most sensitive factors, whereas the mean grain size is the least sensitive factor in the prediction of seismic soil liquefaction potential. The results of this study can provide theoretical support for researchers in selecting appropriate ML algorithms and improving the predictive performance of seismic soil liquefaction potential models.

关键词: seismic soil liquefaction     Bayesian belief network     cone penetration test     parameter learning     structural learning    

A step forward towards a comprehensive framework for assessing liquefaction land damage vulnerability: Exploration from historical data

Mahmood AHMAD, Xiao-Wei TANG, Jiang-Nan QIU, Feezan AHMAD, Wen-Jing GU

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1476-1491 doi: 10.1007/s11709-020-0670-z

摘要: The unprecedented liquefaction-related land damage during earthquakes has highlighted the need to develop a model that better interprets the liquefaction land damage vulnerability (LLDV) when determining whether liquefaction is likely to cause damage at the ground’s surface. This paper presents the development of a novel comprehensive framework based on select case history records of cone penetration tests using a Bayesian belief network (BBN) methodology to assess seismic soil liquefaction and liquefaction land damage potentials in one model. The BBN-based LLDV model is developed by integrating multi-related factors of seismic soil liquefaction and its induced hazards using a machine learning (ML) algorithm-K2 and domain knowledge (DK) data fusion methodology. Compared with the C4.5 decision tree-J48 model, naive Bayesian (NB) classifier, and BBN-K2 ML prediction methods in terms of overall accuracy and the Cohen’s kappa coefficient, the proposed BBN K2 and DK model has a better performance and provides a substitutive novel LLDV framework for characterizing the vulnerability of land to liquefaction-induced damage. The proposed model not only predicts quantitatively the seismic soil liquefaction potential and its ground damage potential probability but can also identify the main reasons and fault-finding state combinations, and the results are likely to assist in decisions on seismic risk mitigation measures for sustainable development. The proposed model is simple to perform in practice and provides a step toward a more sophisticated liquefaction risk assessment modeling. This study also interprets the BBN model sensitivity analysis and most probable explanation of seismic soil liquefied sites based on an engineering point of view.

关键词: Bayesian belief network     liquefaction-induced damage potential     cone penetration test     soil liquefaction     structural learning and domain knowledge    

SPT based determination of undrained shear strength: Regression models and machine learning

Walid Khalid MBARAK, Esma Nur CINICIOGLU, Ozer CINICIOGLU

《结构与土木工程前沿(英文)》 2020年 第14卷 第1期   页码 185-198 doi: 10.1007/s11709-019-0591-x

摘要: The purpose of this study is the accurate prediction of undrained shear strength using Standard Penetration Test results and soil consistency indices, such as water content and Atterberg limits. With this study, along with the conventional methods of simple and multiple linear regression models, three machine learning algorithms, random forest, gradient boosting and stacked models, are developed for prediction of undrained shear strength. These models are employed on a relatively large data set from different projects around Turkey covering 230 observations. As an improvement over the available studies in literature, this study utilizes correct statistical analyses techniques on a relatively large database, such as using a train/test split on the data set to avoid overfitting of the developed models. Furthermore, the validity and consistency of the prediction results are ensured with the correct use of statistical measures like -value and cross-validation which were missing in previous studies. To compare the performances of the models developed in this study with the prior ones existing in literature, all models were applied on the test data set and their performances are evaluated in terms of the resulting root mean squared error ( ) values and coefficient of determination ( ). Accordingly, the models developed in this study demonstrate superior prediction capabilities compared to all of the prior studies. Moreover, to facilitate the use of machine learning algorithms for prediction purposes, entire source code prepared for this study and the collected data set are provided as supplements of this study.

关键词: undrained shear strength     linear regression     random forest     gradient boosting     machine learning     standard penetration test    

Impingement of hollow cone spray on hot porous medium

ZHAO Zhiguo, XIE Maozhao

《能源前沿(英文)》 2008年 第2卷 第3期   页码 273-278 doi: 10.1007/s11708-008-0048-8

摘要: To have a good understanding of the formation of homogenous mixture in a porous medium engine, the interaction between hollow cone spray and hot porous medium was studied numerically by using an improved version of KIVA-3V code. The improved KIVA-3V code is incorporated with an impingement model, heat transfer model and linearized instability sheet atomization (LISA) model to simulate the hollow cone spray. The reasonability of the impingement model and heat transfer model was validated. With a simple model to describe the structure of the porous medium, the interaction between hollow cone spray and hot porous medium was simulated under different ambient pressures and spray cone angles. Computational results show that the fuel spray could be divided into smaller ones, which provides conditions for the quick evaporation of fuel droplets and the mixing of fuel vapor with air. Differences in ambient pressure and spray cone angle affect the distribution of droplets in the porous medium.

关键词: improved version     simple     impingement     atomization     hollow    

Hollow-fiber gas penetration electrodes efficiently produce renewable synthetic fuels

《能源前沿(英文)》 2022年 第16卷 第5期   页码 700-705 doi: 10.1007/s11708-022-0842-8

Enhanced penetration strategies for transdermal delivery

Qiaofei Pan, Yinglin Yu, Dong Chen, Genlong Jiao, Xiaowen Liu

《化学科学与工程前沿(英文)》 2020年 第14卷 第3期   页码 378-388 doi: 10.1007/s11705-019-1913-1

摘要: Transdermal delivery offers several advantages in drug distribution, including convenience, painless administration, avoidance of first-pass metabolism, and ease of termination. However, the natural protective barriers of the skin, such as the stratum corneum, the topmost layer of skin, limit the systemic absorption of external therapeutics via transdermal delivery. Therefore, extensive application of transdermal delivery in medical treatment has been limited. Over the past few years, many formulation strategies and physical technologies, therefore, have been developed to enhance transdermal delivery. This review summarizes various formulation strategies proposed for transdermal delivery and their application in medical treatment.

关键词: transdermal delivery     stratum corneum     enhanced penetration     therapeutics    

of undercut on the lower bound stability of vertical rock escarpment using finite element and power cone

《结构与土木工程前沿(英文)》 doi: 10.1007/s11709-023-0035-5

摘要: Correction to: Effect of undercut on the lower bound stability of vertical rock escarpment using finite element and power cone programming

关键词: finite element power     stability rock escarpment    

of undercut on the lower bound stability of vertical rock escarpment using finite element and power cone

Shuvankar DAS; Debarghya CHAKRABORTY

《结构与土木工程前沿(英文)》 2022年 第16卷 第8期   页码 1040-1055 doi: 10.1007/s11709-022-0841-1

摘要: In the present study, the stability of a vertical rock escarpment is determined by considering the influence of undercut. Lower bound finite element limit analysis in association with Power Cone Programming (PCP) is applied to incorporate the failure of rock mass with the help of the Generalized Hoek-Brown yield criterion. The change in stability due to the presence of undercut is expressed in terms of a non-dimensional stability number (σci/γH). The variations of the magnitude of σci/γH are presented as design charts by considering the different magnitudes of undercut offset (H/vu and wu/vu) from the vertical edge and different magnitudes of Hoek-Brown rock mass strength parameters (Geological Strength Index (GSI), rock parameter (mi,), Disturbance factor (D)). The obtained results indicate that undercut can cause a severe stability problem in rock mass having poor strength. With the help of regression analysis of the computed results, a simplified design equation is proposed for obtaining σci/γH. By performing sensitivity analysis for an undisturbed vertical rock escarpment, we have found that the undercut height ratio (H/vu) is the most sensitive parameter followed by GSI, undercut shape ratio (wu/vu), and mi. The developed design equation as well as design charts can be useful for practicing engineers to determine the stability of the vertical rock escarpment in the presence of undercut. Failure patterns are also presented to understand type of failure and extent of plastic state during collapse.

关键词: undercut     vertical escarpment     stability     Hoek-Brown yield criterion     PCP    

Impacts of cone-structured interface and aperiodicity on nanoscale thermal transport in Si/Ge superlattices

Pengfei JI, Yiming RONG, Yuwen ZHANG, Yong TANG

《能源前沿(英文)》 2018年 第12卷 第1期   页码 137-142 doi: 10.1007/s11708-018-0532-8

摘要: Si/Ge superlattices are promising thermoelectric materials to convert thermal energy into electric power. The nanoscale thermal transport in Si/Ge superlattices is investigated via molecular dynamics (MD) simulation in this short communication. The impact of Si and Ge interface on the cross-plane thermal conductivity reduction in the Si/Ge superlattices is studied by designing cone-structured interface and aperiodicity between the Si and Ge layers. The temperature difference between the left and right sides of the Si/Ge superlattices is set up for nonequilibrium MD simulation. The spatial distribution of temperature is recorded to examine whether the steady-state has been reached. As a crucial factor to quantify thermal transport, the temporal evolution of heat flux flowing through Si/Ge superlattices is calculated. Compared with the even interface, the cone-structured interface contributes remarkable resistance to the thermal transport, whereas the aperiodic arrangement of Si and Ge layers with unequal thicknesses has a marginal influence on the reduction of effective thermal conductivity. The interface with divergent cone-structure shows the most excellent performance of all the simulated cases, which brings a 33% reduction of the average thermal conductivity to the other Si/Ge superlattices with even, convergent cone-structured interfaces and aperiodic arrangements. The design of divergent cone-structured interface sheds promising light on enhancing the thermoelectric efficiency of Si/Ge based materials.

关键词: thermoelectric material     thermal transport     Si/Gesuperlattics     molecular dynamics (MD)    

Influence of short chain ceramides and lipophilic penetration enhancers on the nano-structure of stratum

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

《化学科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 29-36 doi: 10.1007/s11705-013-1302-0

摘要: Oriented stratum corneum model lipid membranes were used to study the influence of the short chain ceramides (CER)[NP] and [AP] as well as the impact of the lipophilic penetration enhancer molecules oleic acid (OA) and isopropyl myristate (IPM) on the lipid nanostructure. The influence of the enhancer molecules were studied using specifically deuterated OA and IPM and neutron diffraction. H NMR spectroscopy was used to study the impact of the ceramides’ degree of order within the stratum corneum model lipid membranes. It was found that CER[NP] forms two very stable phases with high resistance against temperature increase. Phase B showed unusual hydration behavior as no water uptake of this phase was observed. The H NMR spectroscopic measurements showed that CER[NP] based ternary model system had a higher state of lamellar order in comparison to CER[AP] based lipid matrix. The studies confirmed that the short chain ceramides, particularly CER[NP], have a very high impact on the integrity of the Stratum corneum lipid bilayers. The penetration enhancer OA has not influenced the repeat distance of the model membrane based on CER[AP], and was not able to induce a phase separation in the investigated lipid matrix. However, a disorder and a fluidisation of the model membranes were observed when OA was incorporated. IPM showed the same effect but two phases (assigned as phase A and B) appeared, when IPM was used as penetration enhancer and incorporated into the model membrane. Furthermore, two arrangements of IPM were identified in phase A using deuterated IPM. A model of the nanostructure of the Stratum corneum lipid membranes is presented.

关键词: nano-structure of the stratum corneum     ceramide     penetration enhancer     model membrane     neutron diffraction     2H NMR spectroscopy    

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    

Study of mechanism of activating flux increasing weld penetration of AC A-TIG welding for aluminum alloy

HUANG Yong, FAN Ding, FAN Qinghua

《机械工程前沿(英文)》 2007年 第2卷 第4期   页码 442-447 doi: 10.1007/s11465-007-0076-9

摘要: When multi-component flux AF305 is used as surface activating flux for an aluminum alloy, the weld pene tration of activating flux-tungsten inert-gas (A-TIG) welding is over two times more than that of conventional TIG welding. Using A-TIG welding with the modes of alternating current (AC), direct current electrode negative (DCEN) and direct current electrode positive (DCEP), respectively, the flux differently affects weld penetration when the polarity is different. After studied the effect of compelled arc con striction on weld penetration of AC welding, it is believed that the constriction of the whole arc root is not the main mechanism that flux AF305 dramatically improves weld penetration. The penetration has a relationship with the separate distribution of slag on the weld surface. Then, an observation of scanning electron microscopy (SEM) and an electronic data systems (EDS) analysis of slag were performed respectively. The separate distribution of slag on the weld pool during welding and the great constriction of arc spots were confirmed by TIG welding with helium shielding gas. The relationship between slag distribution and weld penetration was studied by adding aluminum powder into flux AF305 to change the distribution of slag. During welding, the separate distribution of slag on the weld pool results in the great constriction of arc spots, an increase in arc spot force, and an increase in Lorentz force within the arc and weld pool. Finally, the weld penetration is increased.

关键词: A-TIG welding     surface     DCEN     electrode negative     increase    

标题 作者 时间 类型 操作

Liquefaction prediction using support vector machine model based on cone penetration data

Pijush SAMUI

期刊论文

Prediction of the shear wave velocity

Amoroso SARA

期刊论文

In situ-based assessment of soil liquefaction potential–Case study of an earth dam in Tunisia

Ikram GUETTAYA,Mohamed Ridha EL OUNI

期刊论文

Application of machine learning algorithms for the evaluation of seismic soil liquefaction potential

Mahmood AHMAD, Xiao-Wei TANG, Jiang-Nan QIU, Feezan AHMAD, Wen-Jing GU

期刊论文

A step forward towards a comprehensive framework for assessing liquefaction land damage vulnerability: Exploration from historical data

Mahmood AHMAD, Xiao-Wei TANG, Jiang-Nan QIU, Feezan AHMAD, Wen-Jing GU

期刊论文

SPT based determination of undrained shear strength: Regression models and machine learning

Walid Khalid MBARAK, Esma Nur CINICIOGLU, Ozer CINICIOGLU

期刊论文

Impingement of hollow cone spray on hot porous medium

ZHAO Zhiguo, XIE Maozhao

期刊论文

Hollow-fiber gas penetration electrodes efficiently produce renewable synthetic fuels

期刊论文

Enhanced penetration strategies for transdermal delivery

Qiaofei Pan, Yinglin Yu, Dong Chen, Genlong Jiao, Xiaowen Liu

期刊论文

of undercut on the lower bound stability of vertical rock escarpment using finite element and power cone

期刊论文

of undercut on the lower bound stability of vertical rock escarpment using finite element and power cone

Shuvankar DAS; Debarghya CHAKRABORTY

期刊论文

Impacts of cone-structured interface and aperiodicity on nanoscale thermal transport in Si/Ge superlattices

Pengfei JI, Yiming RONG, Yuwen ZHANG, Yong TANG

期刊论文

Influence of short chain ceramides and lipophilic penetration enhancers on the nano-structure of stratum

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

期刊论文

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

Tsukasa KATSUMATA, Yoshihiro MIZUTANI, Akira TODOROKI, Ryosuke MATSUZAKI

期刊论文

Study of mechanism of activating flux increasing weld penetration of AC A-TIG welding for aluminum alloy

HUANG Yong, FAN Ding, FAN Qinghua

期刊论文