资源类型

期刊论文 352

会议视频 12

年份

2024 1

2023 19

2022 47

2021 33

2020 25

2019 24

2018 22

2017 29

2016 13

2015 24

2014 16

2013 19

2012 12

2011 9

2010 10

2009 10

2008 9

2007 15

2006 4

2005 2

展开 ︾

关键词

能源 4

不确定性 2

中国 2

保持社交距离 2

医学 2

环境影响 2

2035 1

3D打印 1

cyp17a1 1

Anderson 模型 1

COVID-19 1

GDP年增长率 1

Gossip模型 1

SARS危机 1

WTO 1

一致性 1

三峡工程 1

三维人脸重建；级联回归；形状空间；实时 1

三维细观模拟 1

展开 ︾

检索范围：

排序： 展示方式：

Does environmental infrastructure investment contribute to emissions reduction? A case of China

Xiaoqian SONG, Yong GENG, Ke LI, Xi ZHANG, Fei WU, Hengyu PAN, Yiqing ZHANG

《能源前沿（英文）》 2020年 第14卷 第1期   页码 57-70 doi: 10.1007/s11708-019-0654-7

摘要： Environmental infrastructure investment (EII) is an important environmental policy instrument on responding to greenhouse gas (GHG) emission and air pollution. This paper employs an improved stochastic impact by regression on population, affluence and technology (STRIPAT) model by using panel data from 30 Chinese provinces and municipalities for the period of 2003–2015 to investigate the effect of EII on CO emissions, SO emissions, and PM pollution. The results indicate that EII has a positive and significant effect on mitigating CO emission. However, the effect of EII on SO emission fluctuated although it still contributes to the reduction of PM pollution through technology innovations. Energy intensity has the largest impact on GHG emissions and air pollution, followed by GDP per capita and industrial structure. In addition, the effect of EII on environmental issues varies in different regions. Such findings suggest that policies on EII should be region-specific so that more appropriate mitigation policies can be raised by considering the local realities.

关键词： environmental infrastructure investment (EII)     CO2 emission     SO2 emission     PM2.5 pollution     stochastic impact by regression on population     affluence and technology (STIRPAT) model     governance    

HTML PDF 收藏

图引导正则最小化的随机超梯度的交替方向方法 None

Qiang LAN, Lin-bo QIAO, Yi-jie WANG

《信息与电子工程前沿（英文）》 2018年 第19卷 第6期   页码 755-762 doi: 10.1631/FITEE.1601771

摘要： 提出并比较额外梯度交替方向的几种随机变体方法，称为带拉格朗日函数（SEGL）的随机超梯度交替方向法和带增广拉格朗日函数（SEGAL）的随机超梯度交替方向法。这些方法由两个大规模凸目标函数组成，可最小化图形引导的优化问题。机器学习中一些重要应用遵循图导引优化公式等作为线性回归、逻辑回归、Lasso结构化扩展以及结构化正则化逻辑回归的原则。通过融合逻辑回归和图形引导正则化回归，在几类数据集上进行了试验。试验结果表明所提算法优于其他竞争算法，且在实际应用中，SEGAL比SEGL性能更好。

关键词： 随机优化；图形引导最小化；超梯度法；融合逻辑回归；图导向正则化逻辑回归    

HTML PDF 收藏

Impact of inter-fuel substitution on energy intensity in Ghana

Boqiang LIN, Hermas ABUDU

《能源前沿（英文）》 2020年 第14卷 第1期   页码 27-41 doi: 10.1007/s11708-019-0656-5

摘要： Energy intensity and elasticity, together with inter-fuel substitution are key issues in the current development stage of Ghana. Translog production and ridge regression are applied for studying these issues with a data range of 2000–2015. The current energy dynamics reveal the expected inverse relationship: higher energy intensity and lower elasticity with economic growth. There are evidences of energy-economic challenges: high energy cost, inefficiency and backfire rebound effect. The implications are higher energy losses in the system, more consumption of lower-quality energy together with low energy technology innovation. Energy is wasted and directly not productive with economic activities. It is observed further that the higher energy intensity invariably increases CO emission because approximately 95% of total energy is derived from hydrocarbons and biomass. An inter-fuel substitution future scenario design was further conducted and the results were positive with growth, lower energy intensity, and improved energy efficiency. Therefore, government and energy policymakers should improve energy efficiency, cost, and productiveness. That is, they should change energy compositions and augment energy technology innovation, thus, increasing renewable share to 15% by 2026, reducing wood and charcoal by about 69%, and increasing natural gas to about 776%. Energy policymakers should enhance the installation of smart energy, cloud energy solution, tokenization of energy system and storage.

关键词： energy intensity     energy elasticity     inter-fuel substitution prospects     energy contribution     Translog production approach     ridge regression    

HTML PDF 收藏

Integrated uncertain models for runoff forecasting and crop planting structure optimization of the Shiyang River Basin, north-west China

Fan ZHANG, Mo LI, Shanshan GUO, Chenglong ZHANG, Ping GUO

《农业科学与工程前沿（英文）》 2018年 第5卷 第2期   页码 177-187 doi: 10.15302/J-FASE-2017177

摘要： To improve the accuracy of runoff forecasting, an uncertain multiple linear regression (UMLR) model is presented in this study. The proposed model avoids the transfer of random error generated in the independent variable to the dependent variable, as this affects prediction accuracy. On this basis, an inexact two-stage stochastic programming (ITSP) model is used for crop planting structure optimization (CPSO) with the inputs that are interval flow values under different probabilities obtained from the UMLR model. The developed system, in which the UMLR model for runoff forecasting and the ITSP model for crop planting structure optimization are integrated, is applied to a real case study. The aim of the developed system is to optimize crops planting area with limited available water resources base on the downstream runoff forecasting in order to obtain the maximum system benefit in the future. The solution obtained can demonstrate the feasibility and suitability of the developed system, and help decision makers to identify reasonable crop planting structure under multiple uncertainties.

关键词： crop planting structure optimization     inexact two-stage stochastic programming     runoff forecasting     Shiyang River Basin     uncertain multiple linear regression    

HTML PDF 收藏

Special Column on Multiscale Stochastic Finite Element Method

《结构与土木工程前沿（英文）》 2015年 第9卷 第2期   页码 105-106 doi: 10.1007/s11709-015-0297-7

HTML PDF 收藏

Simulation of bubble column reactors using CFD coupled with a population balance model

Tiefeng WANG

《化学科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 162-172 doi: 10.1007/s11705-009-0267-5

摘要： Bubble columns are widely used in chemical and biochemical processes due to their excellent mass and heat transfer characteristics and simple construction. However, their fundamental hydrodynamic behaviors, which are essential for reactor scale-up and design, are still not fully understood. To develop design tools for engineering purposes, much research has been carried out in the area of computational fluid dynamics (CFD) modeling and simulation of gas-liquid flows. Due to the importance of the bubble behavior, the bubble size distribution must be considered in the CFD models. The population balance model (PBM) is an effective approach to predict the bubble size distribution, and great efforts have been made in recent years to couple the PBM into CFD simulations. This article gives a selective review of the modeling and simulation of bubble column reactors using CFD coupled with PBM. Bubble breakup and coalescence models due to different mechanisms are discussed. It is shown that the CFD-PBM coupled model with proper bubble breakup and coalescence models and interphase force formulations has the ability of predicting the complex hydrodynamics in different flow regimes and, thus, provides a unified description of both the homogeneous and heterogeneous regimes. Further study is needed to improve the models of bubble coalescence and breakup, turbulence modification in high gas holdup, and interphase forces of bubble swarms.

关键词： bubble column     computational fluid dynamics     bubble breakup and coalescence     population balance model     bubble size distribution    

HTML PDF 收藏

Stochastic analysis of laminated composite plate considering stochastic homogenization problem

S. SAKATA,K. OKUDA,K. IKEDA

《结构与土木工程前沿（英文）》 2015年 第9卷 第2期   页码 141-153 doi: 10.1007/s11709-014-0286-2

摘要： This paper discusses a multiscale stochastic analysis of a laminated composite plate consisting of unidirectional fiber reinforced composite laminae. In particular, influence of a microscopic random variation of the elastic properties of component materials on mechanical properties of the laminated plate is investigated. Laminated composites are widely used in civil engineering, and therefore multiscale stochastic analysis of laminated composites should be performed for reliability evaluation of a composite civil structure. This study deals with the stochastic response of a laminated composite plate against the microscopic random variation in addition to a random variation of fiber orientation in each lamina, and stochastic properties of the mechanical responses of the laminated plate is investigated. Halpin-Tsai formula and the homogenization theory-based finite element analysis are employed for estimation of effective elastic properties of lamina, and the classical laminate theory is employed for analysis of a laminated plate. The Monte-Carlo simulation and the first-order second moment method with sensitivity analysis are employed for the stochastic analysis. From the numerical results, importance of the multiscale stochastic analysis for reliability evaluation of a laminated composite structure and applicability of the sensitivity-based approach are discussed.

关键词： stochastic homogenization     multiscale stochastic analysis     microscopic random variation     laminated composite plate    

HTML PDF 收藏

Application of an efficient stochastic calculation method on the seismic analysis of an isolated structure

Wei GUO, Zhiwu YU

《结构与土木工程前沿（英文）》 2012年 第6卷 第4期   页码 379-384 doi: 10.1007/s11709-012-0180-8

摘要： An isolated structure often possesses distinct non-proportional damping characteristics. However, traditional seismic calculation theory and methods are derived based on the assumption that damping is proportional. Based on this drawback, a new, more efficient stochastic calculation method, an improvement on the pseudo-excitation method, is introduced. This method is then applied to the seismic analysis of an isolated structure. By comparing it with the forced decoupling, matrix inversion and iteration methods, it is shown that the presented method can produce accurate results while increasing the efficiency of the stochastic analysis. Moreover, the calculation process of the seismic response of an isolated structure is convergent. Based on the results of the example presented in this paper, the given method is applicable to the seismic analysis of an isolated structure and can be utilized in practice.

关键词： isolated structure     stochastic response     non-proportional damping     efficient     accurate     pseudo-excitation method    

HTML PDF 收藏

Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

《环境科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 43-48 doi: 10.1007/s11783-012-0397-8

摘要： The effects of hydraulic retention time (HRT) on the nitrification activities and population dynamics of a conventional activated sludge system fed with synthetic inorganic wastewater were investigated over a period of 260 days. When the HRT was gradually decreased from 30 to 5 h, the specific ammonium-oxidizing rates (SAOR) varied between 0.32 and 0.45 kg (kg mixed liquor suspended solids (MLSS)·d) , and the specific nitrate-forming rates (SNFR) increased from 0.11 to 0.50 kg (kg MLSS·d) , showing that the decrease in HRT led to a significant increase in the nitrite oxidation activity. According to fluorescence in situ hybridization (FISH) analysis results, the proportion of ammonia-oxidizing bacteria (AOBs) among the total bacteria decreased from 33% to 15% with the decrease in HRT, whereas the fraction of nitrite-oxidizing bacteria (NOBs), particularly the fast-growing sp., increased significantly (from 4% to 15% for NOBs and from 1.5% to 10.6% for sp.) with the decrease in HRT, which was in accordance with the changes in SNFR. A short HRT favored the relative growth of NOBs, particularly the fast-growing sp., in the conventional activated sludge system.

关键词： ammonia-oxidizing bacteria     hydraulic retention time     nitrification activity     nitrite-oxidizing bacteria     population dynamics    

HTML PDF 收藏

Socialized care services for the aged population: System construction and support measures

《工程管理前沿（英文）》 2023年 第10卷 第2期   页码 339-353 doi: 10.1007/s42524-022-0208-2

摘要： Given the aging society, an increase in social demand, information- and communication technology-driven culture, and government policy support emerges to enable the development of the socialized care services system for the aged (SCSSA). The development of the SCSSA would be a significant step toward addressing China’s aging population. However, the construction of the SCSSA challenges the theories and methods of traditional elderly care service system construction. Specifically, the implementation path for such elderly care service policies is unclear, the necessary technological support is insufficient, and the mechanism for integrating intelligent information technology remains underexplored. Thus, this paper focuses on the needs of the elderly, grounded in the context of the changing elderly care service policies in China, and proposes a research paradigm that integrates system construction and support measure embedding. We then construct the original SCSSA, which includes “material + spirit + medical treatment + healthcare” and propose a method of optimization and iteration. Finally, we build the research framework of systematic support measures from the perspectives of policy reconstruction, institutional embeddedness, and technical support. Our work provides theoretical support and practical guidance for the construction and dynamic optimization of the SCSSA, thus making a significant contribution that will help China effectively cope with its aging society.

关键词： socialized     care service for the elderly     system construction     support measure    

HTML PDF 收藏

Hierarchical modeling of stochastic manufacturing and service systems

Zhe George ZHANG, Xiaoling YIN

《工程管理前沿（英文）》 2017年 第4卷 第3期   页码 295-303 doi: 10.15302/J-FEM-2017047

摘要： This paper presents a review of methodologies for analyzing stochastic manufacturing and service systems. On the basis of the scale and level of details of operations, we can study stochastic systems using micro-, meso-, and macro-scopic models. Such a classification unifies stochastic modeling theory. For each model type, we highlight the advantages and disadvantages and the applicable situations. Micro-scopic models are based on quasi-birth-and-death process because of the phase-type distributed service times and/or Markov arrival processes. Such models are appropriate for modeling the detailed operations of a manufacturing system with relatively small number of servers (production facilities). By contrast, meso-scopic and macro-scopic models are based on the functional central limit theorem (FCLT) and functional strong law of large numbers (FSLLN), respectively, under heavy-traffic regimes. These high-level models are appropriate for modeling large-scale service systems with many servers, such as call centers or large service networks. This review will help practitioners select the appropriate level of modeling to enhance their understanding of the dynamic behavior of manufacturing or service systems. Enhanced understanding will ensure that optimal policies can be designed to improve system performance. Researchers in operation analytics and optimization of manufacturing and logistics also benefit from such a review.

关键词： stochastic modeling     QBD process     PH distribution     heavy traffic limits     diffusion process    

HTML PDF 收藏

Multiple regression models for energy consumption of office buildings in different climates in China

Siyu ZHOU, Neng ZHU

《能源前沿（英文）》 2013年 第7卷 第1期   页码 103-110 doi: 10.1007/s11708-012-0220-z

摘要： The energy consumption of office buildings in China has been growing significantly in recent years. Obviously, there are significant relationships between building envelope and the energy consumption of office buildings. The 8 key building envelope influencing factors were found in this paper to evaluate their effects on the energy consumption of the air-conditioning system. The typical combinations of the key influencing factors were performed in Trnsy simulation. Then on the basis of the simulated results, the multiple regression models were developed respectively for the four climates of China—hot summer and warm winter, hot summer and cold winter, cold, and severely cold. According to the analysis of regression coefficients, the appropriate building envelope design schemes were discussed in different climates. At last, the regression model evaluations consisting of the simulation evaluations and the actual case evaluations were performed to verify the feasibility and accuracy of the regression models. The error rates are within±5% in the simulation evaluations and within±15% in the actual case evaluations. It is believed that the regression models developed in this paper can be used to estimate the energy consumption of office buildings in different climates when various building envelope designs are considered.

关键词： regression model     energy consumption     building envelope     office building     different climates    

HTML PDF 收藏

Discrete-event stochastic systems with correlated inputs: Modeling and performance evaluation

《工程管理前沿（英文）》 2022年 第9卷 第2期   页码 214-220 doi: 10.1007/s42524-022-0192-6

摘要： In the majority of the previous works on discrete-event stochastic systems, they have been assumed to have independent input processes. However, in many applications, these input processes can be highly correlated. Furthermore, the performance measures of the systems with correlated inputs can be significantly different from those with independent inputs. In this paper, we provide an overview on some commonly used methods for modeling correlated input processes, and we discuss the difficulties and possible future research topics in the study of discrete-event stochastic systems with correlated inputs.

关键词： discrete-event stochastic system     correlated input     performance evaluation    

HTML PDF 收藏

Obesity and overweight prevalence and its association with undiagnosed hypertension in Shanghai population, China: a cross-sectional population-based survey

null

《医学前沿（英文）》 2012年 第6卷 第3期   页码 322-328 doi: 10.1007/s11684-012-0204-8

摘要：

The aim of this study was to determine the prevalence of overweight and obese subjects in the Shanghai population of China and its association with undiagnosed hypertension, by taking age, gender and place of residence (urban or suburban) into account. A cross-sectional population-based survey was conducted in 2007. The sample included 13 359 participants aged 15–69 years. Weight, height, and blood pressure were recorded, and information about gender, age and place of residence was obtained. Overweight and obesity prevalence were calculated by the body mass index (BMI) definition recommended by Working Group on Obesity in China (normal weight, 18.5–23.9 kg/m2; overweight, 24–27.9 kg/m2; obesity,≥28 kg/m2). Undiagnosed hypertension was defined by China criteria in accord with that of WHO-ISH (subjects with systolic pressure≥140 mmHg, and/or diastolic pressure≥90 mmHg). Multiple logistic regression analyses were used to assess the association of overweight or obesity with undiagnosed hypertension by adjusting for age, gender and place of residence. The overall overweight, obesity, and undiagnosed hypertension prevalence were 27.6% (95% CI: 26.8–28.4), 6.6% (95% CI: 6.2–7.0), and 15.5% (95% CI: 14.9–16.1), respectively. Compared to normal weight subjects, the odds ratios (OR) for subjects who were overweight and had hypertension was 2.33 (95% CI: 2.10–2.59); that for obesity and hypertension was 4.27 (95% CI: 3.66–4.99). These data suggest that overweight and obesity prevalence and their association with undiagnosed hypertension are high in our study population.

关键词： overweight     obesity     undiagnosed hypertension     prevalence     association    

HTML PDF 收藏

Prognostic analysis of chronic myeloid leukemia in Chinese population in an imatinib era

null

《医学前沿（英文）》 2012年 第6卷 第2期   页码 204-211 doi: 10.1007/s11684-012-0202-x

摘要：

We evaluated the outcomes of chronic myeloid leukemia (CML) patients in three clinical phases, namely, chronic (CP), accelerated (AP), and blast (BP) phases, receiving imatinib treatment. The single-institution treatment experiences of Chinese patients with CML were presented. A total of 275 CML patients (CP, 210; AP, 24; and BP, 41) who received imatinib between February 2001 and April 2008 were enrolled in this study. We evaluated the responses (hematologic, cytogenetic, and molecular), overall survival (OS), treatment event-free survival (EFS), and prognostic factors of outcome. At the cut-off point, the complete cytogenetic response (CCyR) and complete molecular response rates of patients in the CP were 84.7% and 61.9%, respectively, which were significantly higher than those of patients in the AP (50% and 29.1%, respectively, both P<0.001) and BP (24.3% and 9.7%, respectively, both P<0.001). The estimated five-year OS and five-year EFS rates were 93.2% and 86.4% for CP patients, as well as 64.5% and 50.9% for AP patients, which were significantly higher than those for BP patients (P<0.001). In CP patients, univariate analysis revealed that early treatment with imatinib, achieving CCyR within 12 months, additional cytogenetic abnormalities, and kinase domain mutations were associated with the treatment outcome. More patients are needed to carry out multivariate analysis.

关键词： imatinib     chronic myeloid leukemia     complete cytogenetic response    

HTML PDF 收藏

标题 作者 时间 类型 操作

Does environmental infrastructure investment contribute to emissions reduction? A case of China

Xiaoqian SONG, Yong GENG, Ke LI, Xi ZHANG, Fei WU, Hengyu PAN, Yiqing ZHANG

期刊论文

图引导正则最小化的随机超梯度的交替方向方法

Qiang LAN, Lin-bo QIAO, Yi-jie WANG

期刊论文

Impact of inter-fuel substitution on energy intensity in Ghana

Boqiang LIN, Hermas ABUDU

期刊论文

Integrated uncertain models for runoff forecasting and crop planting structure optimization of the Shiyang River Basin, north-west China

Fan ZHANG, Mo LI, Shanshan GUO, Chenglong ZHANG, Ping GUO

期刊论文

Special Column on Multiscale Stochastic Finite Element Method

期刊论文

Simulation of bubble column reactors using CFD coupled with a population balance model

Tiefeng WANG

期刊论文

Stochastic analysis of laminated composite plate considering stochastic homogenization problem

S. SAKATA,K. OKUDA,K. IKEDA

期刊论文

Application of an efficient stochastic calculation method on the seismic analysis of an isolated structure

Wei GUO, Zhiwu YU

期刊论文

Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

期刊论文

Socialized care services for the aged population: System construction and support measures

期刊论文

Hierarchical modeling of stochastic manufacturing and service systems

Zhe George ZHANG, Xiaoling YIN

期刊论文

Multiple regression models for energy consumption of office buildings in different climates in China

Siyu ZHOU, Neng ZHU

期刊论文

Discrete-event stochastic systems with correlated inputs: Modeling and performance evaluation

期刊论文

Obesity and overweight prevalence and its association with undiagnosed hypertension in Shanghai population, China: a cross-sectional population-based survey

null

期刊论文

Prognostic analysis of chronic myeloid leukemia in Chinese population in an imatinib era

null

期刊论文