资源类型

期刊论文 2426

会议视频 35

会议信息 2

年份

2024 2

2023 131

2022 187

2021 170

2020 144

2019 145

2018 119

2017 120

2016 107

2015 129

2014 127

2013 99

2012 114

2011 104

2010 118

2009 101

2008 103

2007 119

2006 62

2005 47

展开 ︾

关键词

数学模型 13

数值模拟 12

模型试验 9

能源 9

风险分析 9

影响因素 7

模型 7

COVID-19 6

人工智能 5

可持续发展 5

遗传算法 5

DX桩 4

不确定性 4

分析 4

对策 4

环境 4

神经网络 4

管理 4

裂缝 4

展开 ︾

检索范围：

排序： 展示方式：

Evaluation of ICUs and weight of quality control indicators: an exploratory study based on Chinese ICU

《医学前沿（英文）》 2023年 第17卷 第4期   页码 675-684 doi: 10.1007/s11684-022-0970-x

摘要： This study aimed to explore key quality control factors that affected the prognosis of intensive care unit (ICU) patients in Chinese mainland over six years (2015−2020). The data for this study were from 31 provincial and municipal hospitals (3425 hospital ICUs) and included 2 110 685 ICU patients, for a total of 27 607 376 ICU hospitalization days. We found that 15 initially established quality control indicators were good predictors of patient prognosis, including percentage of ICU patients out of all inpatients (%), percentage of ICU bed occupancy of total inpatient bed occupancy (%), percentage of all ICU inpatients with an APACHE II score ≥15 (%), three-hour (surviving sepsis campaign) SSC bundle compliance (%), six-hour SSC bundle compliance (%), rate of microbe detection before antibiotics (%), percentage of drug deep venous thrombosis (DVT) prophylaxis (%), percentage of unplanned endotracheal extubations (%), percentage of patients reintubated within 48 hours (%), unplanned transfers to the ICU (%), 48-h ICU readmission rate (%), ventilator associated pneumonia (VAP) (per 1000 ventilator days), catheter related blood stream infection (CRBSI) (per 1000 catheter days), catheter-associated urinary tract infections (CAUTI) (per 1000 catheter days), in-hospital mortality (%). When exploratory factor analysis was applied, the 15 indicators were divided into 6 core elements that varied in weight regarding quality evaluation: nosocomial infection management (21.35%), compliance with the Surviving Sepsis Campaign guidelines (17.97%), ICU resources (17.46%), airway management (15.53%), prevention of deep-vein thrombosis (14.07%), and severity of patient condition (13.61%). Based on the different weights of the core elements associated with the 15 indicators, we developed an integrated quality scoring system defined as F score=21.35%×nosocomial infection management + 17.97%×compliance with SSC guidelines + 17.46%×ICU resources + 15.53%×airway management + 14.07%×DVT prevention + 13.61%×severity of patient condition. This evidence-based quality scoring system will help in assessing the key elements of quality management and establish a foundation for further optimization of the quality control indicator system.

关键词： critical care medicine     quality control     evaluation     exploratory factor analysis (EFA) model    

HTML PDF 收藏

Industrial eco-efficiency and its spatial-temporal differentiation in China

Wei YANG, Fengjun JIN, Chengjin WANG, Chen LV

《环境科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 559-568 doi: 10.1007/s11783-012-0400-4

摘要： The aim of this paper is to study the spatial-temporal differentiation of industrial eco-efficiency in China. Using methods based on the data envelopment analysis (DEA) model and exploratory spatial data analysis (ESDA) and data from 1985, 1995, 2005, and 2008 of 30 provinces in China, the spatial-temporal pattern changes in industrial eco-efficiency are discussed. The results show that: first, the patterns of industrial eco-efficiency are dominated by clustering of relatively low efficiency provinces; second, spatial relationships between the industrial eco-efficiencies of different provinces changed slightly throughout the period and the provinces persistently exhibit spatial concentration of relatively low industrial eco-efficiency; finally, there is an obvious trend in the polarization of industrial eco-efficiency, i.e., the higher level spatial units are concentrated in eastern China, and the lower level spatial units are mainly in western and central China.

关键词： industrial eco-efficiency     data envelopment analysis (DEA) model     exploratory spatial data analysis (ESDA)    

HTML PDF 收藏

Modelling and analysis of FMS productivity variables by ISM, SEM and GTMA approach

null

《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 218-232 doi: 10.1007/s11465-014-0309-7

摘要：

Productivity has often been cited as a key factor in a flexible manufacturing system (FMS) performance, and actions to increase it are said to improve profitability and the wage earning capacity of employees. Improving productivity is seen as a key issue for survival and success in the long term of a manufacturing system. The purpose of this paper is to make a model and analysis of the productivity variables of FMS. This study was performed by different approaches viz. interpretive structural modelling (ISM), structural equation modelling (SEM), graph theory and matrix approach (GTMA) and a cross-sectional survey within manufacturing firms in India. ISM has been used to develop a model of productivity variables, and then it has been analyzed. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) are powerful statistical techniques. CFA is carried by SEM. EFA is applied to extract the factors in FMS by the statistical package for social sciences (SPSS 20) software and confirming these factors by CFA through analysis of moment structures (AMOS 20) software. The twenty productivity variables are identified through literature and four factors extracted, which involves the productivity of FMS. The four factors are people, quality, machine and flexibility. SEM using AMOS 20 was used to perform the first order four-factor structures. GTMA is a multiple attribute decision making (MADM) methodology used to find intensity/quantification of productivity variables in an organization. The FMS productivity index has purposed to intensify the factors which affect FMS.

关键词： FMS     ISM     EFA     SEM     GTMA    

HTML PDF 收藏

An exploratory study for predicting component reliability with new load conditions

Zhengwei HU, Xiaoping DU

《机械工程前沿（英文）》 2019年 第14卷 第1期   页码 76-84 doi: 10.1007/s11465-018-0522-x

摘要： Reliability is important to design innovation. A new product should be not only innovative, but also reliable. For many existing components used in the new product, their reliability will change because the applied Loads are different from the ones for which the components are originally designed and manufactured. Then the new reliability must be re-evaluated. The system designers of the new product, however, may not have enough information to perform this task. With a beam problem as a case study, this study explores a feasible way to re-evaluate the component reliability with new Loads given the following information: The original reliability of the component with respect to the component Loads and the distributions of the new component Loads. Physics-based methods are employed to build the equivalent component limit-state function that can predict the component failure under the new Loads. Since the information is limited, the re-evaluated component reliability is given by its maximum and minimum values. The case study shows that good accuracy can be obtained even though the new reliability is provided with the aforementioned interval.

关键词： reliability     component     failure mode     prediction     random variable    

HTML PDF 收藏

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 877-894 doi: 10.1007/s11709-021-0756-2

摘要： Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.

关键词： bridges     multi-lane factor     traffic load     lane load disparity     multi-truck presence     weigh-in-motion data    

HTML PDF 收藏

Interactive effects of high-speed rail on nodal zones in a city: exploratory study on China

Guo LIU, Kunhui YE

《工程管理前沿（英文）》 2019年 第6卷 第3期   页码 327-335 doi: 10.1007/s42524-019-0051-2

摘要： The arrival of the high-speed rail (HSR) era has accelerated the pace of urban development, but its broad socioeconomic impact remains subject to intense debates. This research aims to propose a model for measuring the impact of HSR operation on HSR stations and the surrounding areas, which this research call the HSR-based nodal zone (HNZ). The proposed model is composed of two variables (i.e., transportation situation and vitality) and three subsystems (i.e., economic, societal, and environmental). Data were collected in China through questionnaire survey. Results indicate that the effects of HSR operation on HNZ are multidimensional, transportation vitality has an intermediary role in the effects, and the effects on the physical environment are negative. This study presents an early examination of the impact of HSR operation on the HSR stations and relevant areas and contributes new evidence to academic debates on the contribution of HSR to urban development. Accordingly, urban development policies should be built on the mechanism of HSR in driving the growth of HNZ.

关键词： high-speed rail     nodal zone     interactive effects     sustainable urbanization     China    

HTML PDF 收藏

一种基于多因素分析和多模型集成的海洋溶解氧浓度时间序列预测混合神经网络模型 Article

刘辉, 杨睿, 段铸, 吴海平

《工程（英文）》 2021年 第7卷 第12期   页码 1751-1765 doi: 10.1016/j.eng.2020.10.023

摘要：

溶解氧是水产养殖的重要指标，准确预测溶解氧浓度可有效提高水产品质量。本文提出了一种新的溶解氧混合预测模型，该模型包括多因素分析、自适应分解和优化集成三个阶段。首先，考虑到影响溶解氧浓度的因素复杂繁多，采用灰色关联度法筛选出与溶解氧关系最密切的环境因素，多因素的考虑使得模型融合更加有效。其次，运用经验小波变换方法自适应地将溶解氧、水温、盐度和氧饱和度等序列分解为子序列。然后，利用5个基准模型对经验小波变换分解出的子序列进行预测，这五个子预测模型的集成权重通过粒子群优化和引力搜索算法计算得出。最后，通过加权分配得到溶解氧多因素集成模型。来自太平洋岛屿海洋观测系统希洛WQB04站收集的时间序列数据验证了该模型的性能。实验的评价指标包括Nash-Sutcliffe效率系数、Kling-Gupta效率系数、平均绝对百分比误差、误差标准差和决定系数。实例分析表明：①所提出的模型能够获得优异的溶解氧预测结果；②该模型优于文中其他对比模型；③预测模型可用于分析溶解氧变化趋势，便于管理者能够做出更好的决策。

关键词： 溶解氧浓度预测     时间序列多步预测     多因素分析     经验小波变化分解     多模型优化集成    

HTML PDF 收藏

品牌竞争力影响因素分析

邴红艳

《中国工程科学》 2002年 第4卷 第5期   页码 79-83

摘要：

跨国公司实施全球战略，从产品输出、资本输出到品牌输出，这种以品牌为旗帜，凭借雄厚的资本和先进技术的综合输出，对国内民族品牌形成巨大冲击并提出了严峻挑战。面对外国品牌的大举抢滩，民族品牌竞争乏力的问题日益显露。通过对品牌竞争力影响要素的分析，探讨了提髙品牌竞争力的对策。

关键词： 品牌竞争力     影响因素     分析     对策    

HTML PDF 收藏

The formation mechanism and the influence factor of residual stress in machining

null

《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 265-269 doi: 10.1007/s11465-014-0311-0

摘要：

Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses in cutting. An important conclusion is drawn that the accumulated plastic strain is the main factor which determines the nature and the magnitude of surface residual stresses in the workpiece. On the basis of the analytical model for residual stress, a series of simulations for residual stress prediction during cutting AISI 1045 steel are implemented in order to obtain the influences of cutting speed, depth of cut and tool edge radius on surface residual stress in the workpiece. And these influences are explained from the perspective of formation mechanism of residual stress in cutting. The conclusions have good applicability and can be used to guide the parameters selection in actual production.

关键词： residual stress     analytical model     strain     plastic     cutting parameter    

HTML PDF 收藏

Factor analysis for the statistical modeling of earthquake-induced landslides

Jeng-Wen LIN, Meng-Hsun HSIEH, Yu-Jen LI

《结构与土木工程前沿（英文）》 2020年 第14卷 第1期   页码 123-126 doi: 10.1007/s11709-019-0582-y

摘要： Earthquake-induced landslides are difficult to assess and predict owing to the inherent unpredictability of earthquakes. In most existing studies, the landslide potential is statistically assessed by collecting and analyzing the data of historical landslide events and earthquake observation records. Unlike rainfall-induced landslides, earthquake-induced landslides cannot be predicted in advance using real-time monitoring systems, and the development of the models for these landslides should instead depend on early earthquake warnings and estimations. Hence, in this study, factor analysis was performed and the frequency distribution method was employed to investigate the potential risk of the landslides caused by earthquakes. Factors such as the slope gradient, lithology (geology), aspect, and elevation were selected and classified as influential factors to facilitate the construction of a landslide database for the area of study.

关键词： earthquake     factor analysis     slope landslides     statistical modeling    

HTML PDF 收藏

Regional characteristics of industrial energy efficiency in China: application of stochastic frontier analysis

Tao HUANG,Akio ONISHI,Feng SHI,Masafumi MORISUGI,Mjo Lwin CHERRY

《环境科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 506-521 doi: 10.1007/s11783-014-0656-y

摘要： This paper analyzed regional industrial energy efficiency in China with Total-Factor Energy Efficiency (TFEE). The East region has the best energy efficiency and the Central and the West regions stand as the second and the third respectively. However, it is found that industrial energy efficiency of all regions increased from 1998 to 2006. This result is consistent with level of economic development of every region. The industries of all provinces in China are not yet at the frontier efficiency position, therefore, to the frontier as target, their technology levels and production processes should be adjusted accordingly. Compared with the conventional energy efficiency, the inverse of energy intensity, which is defined as the ratio of actual output to energy input, is regarded as Single-Factor Energy Efficiency (SFEE) index. Although TFEE ranks are not changed for each region, they are different for each province. The comparative result also shows that the substitution among inputs (labor, capital stock, and energy) to produce the output is significant. The SFEE scores could be over-estimated if energy is taken as the single input in the production. Finally, we identified determining factors affecting industrial energy efficiency using Tobit model. The results indicate that an increase of per capita Gross Domestic Product (GDP), the percentage of output value of industry invested by Hong Kong, Macao, Taiwan and abroad, energy price and investment of scientific and technological activities for industry could be possible contributors and drivers to the industrial energy efficiency. However, increasing of heavy industry will lead to worse industrial energy efficiency.

关键词： industrial energy efficiency     stochastic frontier analysis     total-factor energy efficiency     single factor energy efficiency    

HTML PDF 收藏

Multivariable regression model for Fox depth correction factor

Ravi Kant MITTAL, Sanket RAWAT, Piyush BANSAL

《结构与土木工程前沿（英文）》 2019年 第13卷 第1期   页码 103-109 doi: 10.1007/s11709-018-0474-6

摘要： This paper presents a simple and efficient equation for calculating the Fox depth correction factor used in computation of settlement reduction due to foundation embedment. Classical solution of Boussinesq theory was used originally to develop the Fox depth correction factor equations which were rather complex in nature. The equations were later simplified in the form of graphs and tables and referred in various international code of practices and standard texts for an unsophisticated and quick analysis. However, these tables and graphs provide the factor only for limited values of the input variables and hence again complicates the process of automation of analysis. Therefore, this paper presents a non-linear regression model for the analysis of effect of embedment developed using “IBM Statistical Package for the Social Sciences” software. Through multiple iterations, the value of coefficient of determination is found to reach 0.987. The equation is straightforward, competent and easy to use for both manual and automated calculation of the Fox depth correction factor for wide range of input values. Using the developed equation, parametric study is also conducted in the later part of the paper to analyse the extent of effect of a particular variable on the Fox depth factor.

关键词： settlement     embedment     Fox depth correction factor     regression     multivariable    

HTML PDF 收藏

Effect of interface adhesion factor on the bearing capacity of strip footing placed on cohesive soil

《结构与土木工程前沿（英文）》 2021年 第15卷 第6期   页码 1494-1503 doi: 10.1007/s11709-021-0768-y

摘要： The problem related to bearing capacity of footing either on pure soil or on pure rock mass has been investigated over the years. Currently, no study deals with the bearing capacity of strip footing on a cohesive soil layer overlying rock mass. Therefore, by implementing the lower bound finite element limit analysis in conjunction with the second-order cone programming and the power cone programming, the ultimate bearing capacity of a strip footing located on a cohesive soil overlying rock mass is determined in this study. By considering the different values of interface adhesion factor (αcr) between the cohesive soil and rock mass, the ultimate bearing capacity of strip footing is expressed in terms of influence factor (If) for different values of cohesive soil layer cover ratio (Tcs/B). The failure of cohesive soil is modeled by using Mohr−Coulomb yield criterion, whereas Generalized Hoek−Brown yield criterion is utilized to model the rock mass at failure. The variations ofIf with different magnitudes of αcr are studied by considering the influence of the rock mass strength parameters of beneath rock mass layer. To examine stress distribution at different depths, failure patterns are also plotted.

关键词： bearing capacity     soil-rock interface     Hoek−Brown yield criterion     plasticity     limit analysis    

HTML PDF 收藏

A chemometric analysis on the fluorescent dissolved organic matter in a full-scale sequencing batch reactor

Chen Qian, Wei Chen, Wei-Hua Li, Han-Qing Yu

《环境科学与工程前沿（英文）》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0962-2

摘要： Rapid monitoring of water quality is crucial to the operation of municipal wastewater treatment plants (WWTPs). Fluorescence excitation-emission matrix (EEM) in combination with parallel factor analysis (PARAFAC) has been used as a powerful tool for the characterization of dissolved organic matter (DOM) in WWTPs. However, a recent work has revealed the drawback of PARAFAC analysis, i.e., overestimating the component number. A novel method, parallel factor framework-clustering analysis (PFFCA), has been developed in our earlier work to resolve this drawback of PARAFAC. In the present work, both PARAFAC and PFFCA were used to analyze the EEMs of water samples from a full-scale WWTP from a practical application point of view. The component number and goodness-of-fit from these two methods were compared and the relationship between the relative score change of component and the actual concentration was investigated to evaluate the estimation error introduced by both methods. PFFCA score and actual concentration exhibited a higher correlation coefficient ( = 0.870) compared with PARAFAC ( <0.771), indicating that PFFCA provided a more accurate relative change estimation than PARAFAC. The results suggest that use of PARAFAC may cause confusion in selecting the component number, while EEM-PFFCA is a more reliable alternative approach for monitoring water quality in WWTPs.

关键词： Wastewater treatment plants (WWTPs)     Excitation-emission matrix (EEM)     Parallel factor (PARAFAC)     Parallel factor framework-clustering analysis (PFFCA)    

HTML PDF 收藏

Heuristic solution using decision tree model for enhanced XML schema matching of bridge structural calculation

Sang I. PARK, Sang-Ho LEE

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1403-1417 doi: 10.1007/s11709-020-0666-8

摘要： Research on the quality of data in a structural calculation document (SCD) is lacking, although the SCD of a bridge is used as an essential reference during the entire lifecycle of the facility. XML Schema matching enables qualitative improvement of the stored data. This study aimed to enhance the applicability of XML Schema matching, which improves the speed and quality of information stored in bridge SCDs. First, the authors proposed a method of reducing the computing time for the schema matching of bridge SCDs. The computing speed of schema matching was increased by 13 to 1800 times by reducing the checking process of the correlations. Second, the authors developed a heuristic solution for selecting the optimal weight factors used in the matching process to maintain a high accuracy by introducing a decision tree. The decision tree model was built using the content elements stored in the SCD, design companies, bridge types, and weight factors as input variables, and the matching accuracy as the target variable. The inverse-calculation method was applied to extract the weight factors from the decision tree model for high-accuracy schema matching results.

关键词： structural calculation document     bridge structure     XML Schema matching     weight factor     data mining     decision tree model    

HTML PDF 收藏

标题 作者 时间 类型 操作

Evaluation of ICUs and weight of quality control indicators: an exploratory study based on Chinese ICU

期刊论文

Industrial eco-efficiency and its spatial-temporal differentiation in China

Wei YANG, Fengjun JIN, Chengjin WANG, Chen LV

期刊论文

Modelling and analysis of FMS productivity variables by ISM, SEM and GTMA approach

null

期刊论文

An exploratory study for predicting component reliability with new load conditions

Zhengwei HU, Xiaoping DU

期刊论文

A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

期刊论文

Interactive effects of high-speed rail on nodal zones in a city: exploratory study on China

Guo LIU, Kunhui YE

期刊论文

一种基于多因素分析和多模型集成的海洋溶解氧浓度时间序列预测混合神经网络模型

刘辉, 杨睿, 段铸, 吴海平

期刊论文

品牌竞争力影响因素分析

邴红艳

期刊论文

The formation mechanism and the influence factor of residual stress in machining

null

期刊论文

Factor analysis for the statistical modeling of earthquake-induced landslides

Jeng-Wen LIN, Meng-Hsun HSIEH, Yu-Jen LI

期刊论文

Regional characteristics of industrial energy efficiency in China: application of stochastic frontier analysis

Tao HUANG,Akio ONISHI,Feng SHI,Masafumi MORISUGI,Mjo Lwin CHERRY

期刊论文

Multivariable regression model for Fox depth correction factor

Ravi Kant MITTAL, Sanket RAWAT, Piyush BANSAL

期刊论文

Effect of interface adhesion factor on the bearing capacity of strip footing placed on cohesive soil

期刊论文

A chemometric analysis on the fluorescent dissolved organic matter in a full-scale sequencing batch reactor

Chen Qian, Wei Chen, Wei-Hua Li, Han-Qing Yu

期刊论文

Heuristic solution using decision tree model for enhanced XML schema matching of bridge structural calculation

Sang I. PARK, Sang-Ho LEE

期刊论文