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Bent函数 1

DX桩 1

GPS轨迹 1

MCDM决策 1

Spark 1

Walsh谱 1

Walsh谱分解式 1

万有引力定律 1

下泄水温公式 1

严格雪崩准则 1

中药，类风湿关节炎，循证治疗，展望 1

乘客热点预测 1

乳液共聚合 1

任务规划；机器人；规划领域定义语言（PDDL）；回答集程序（ASP） 1

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Effect of heat transfer coefficient of steam turbine rotor on thermal stress field under off-design condition

Jie GUO,Danmei XIE,Hengliang ZHANG,Wei JIANG,Yan ZHOU

《能源前沿（英文）》 2016年第10卷第1期页码 57-64 doi: 10.1007/s11708-015-0385-3

摘要： The precise calculation of temperature and thermal stress field of steam turbine rotor under off-design conditions is of paramount significance for safe and economic operation, in which an accurate calculation of heat transfer (HT) coefficient plays a decisive role. HT coefficient changes dramatically along with working conditions. First, a finite element analysis of rotor model, applied with ordinary rotor materials, has been conducted to investigate the temperature and thermal stress difference along with the change of HT coefficient from 20 W/(m ·°C) to 20000 W/(m ·°C). Next, the differentiation between existing empirical formulas has been analyzed from the aspect of physical significance of non-dimension parameters. Finally, a verifying case of the cold startup of a 1000MW unit has been proceeded. The result shows that the accuracy of coefficient calculation when steam parameters are low has a greater influence on that of rotor temperature and thermal stress, which means a precise empirical HT coefficient formula, like the Sarkar formula is strongly recommended. When steam parameters are high and HT coefficient is larger than 10 W/(m ·°C), there will be barely any influence on the calculation of thermal stress. This research plays a constructive role in the calculation and analysis of thermal stress.

关键词： steam turbine rotor thermal stress heat transfer coefficient empirical formula

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Prediction of the theoretical and semi-empirical model of ambient temperature

Foued CHABANE,Noureddine MOUMMI,Abdelhafid BRIMA,Abdelhafid MOUMMI

《能源前沿（英文）》 2016年第10卷第3期页码 268-276 doi: 10.1007/s11708-016-0413-y

摘要： It is well known that the ambient temperature is a sensitive parameter which has a great effect on biology, technology, geology and even on human behavior. A prediction is a statement about an uncertain event. It is often, but not always, based upon experience or knowledge. Although guaranteed accurate information about the future is in many cases impossible, prediction can be useful to assist in making plans about possible developments. As a result, temperature profiles can be developed which accurately represent the expected ambient temperature exposure that this environment experiences during measurement. The ambient temperature over time is modeled based on the previous and data and using a Lagrange interpolation. To observe the comprehensive variation of ambient temperature the profile must be determined numerically. The model proposed in this paper can provide an acceptable way to measure the change in ambient temperature.

关键词： ambient temperature environment correlation theoretical model semi-empirical

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Detection of schedule delay risk of empirical construction projects

Tsegay GEBREHIWET, Hanbin LUO

《工程管理前沿（英文）》 2018年第5卷第2期页码 251-267 doi: 10.15302/J-FEM-2018086

摘要： In Ethiopian construction projects, schedule delay risk is a predominant issue because it is not properly addressed. Although several studies have been focused on the various effects of risk in construction projects, limited efforts have been made to investigate the typical and the overall schedule delay risk. In this study, our aim is to detect the typical and overall schedule delay risk throughout the construction project lifecycle, which consists of the pre-construction, construction, and post-construction stages, and compare the stages with each other. Common criteria, sub-criteria, and attributes were developed for all alternatives for the purpose of making a risk decision. The methodology that was followed integrated the multiple-criteria decision-making (MCDM) model of fuzzy analytic hierarchy process comprehensive evaluation (FAHPCE) and the relative important index (RII). Data were collected from 77 participants, who were selected through purposive sampling from different contracting organizations in Ethiopian construction projects by means of questionnaires that were distributed to experienced experts. The findings showed that there is a typical delay risk either in the type or in the level of the different construction activities. Consequently, the most influenced alternative is the construction stage because of the high-risk responsibility, resource, and contract condition related criteria. The post-construction stage was the second most influenced stage because of the high-risk responsibility-related criteria. The pre-constructed stage was the least influenced stage that consist high-risk criteria of responsibility, resource, and contract condition related. These differences provided noteworthy information about risk mitigation in construction projects by identifying the exact risk level on specific activity to make appropriate decision.

关键词： fuzzy analytic hierarchy process comprehensive evaluation construction project detection of delay risk relative important index

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Relative vibration identification of cutter and workpiece based on improved bidimensional empirical mode

Jiasheng LI, Xingzhan LI, Wei WEI, Pinkuan LIU

《机械工程前沿（英文）》 2020年第15卷第2期页码 227-239 doi: 10.1007/s11465-020-0587-1

摘要： In the process of cutting, the relative vibration between the cutter and the workpiece has an important effect on the surface topography. In this study, the bidimensional empirical mode decomposition (BEMD) method is used to identify such effect. According to Riesz transform theory, a type of isotropic monogenic signal is proposed. The boundary data is extended on the basis of a similarity principle that deals with serious boundary effect problem. The decomposition examples show that the improved BEMD can effectively solve the problem of boundary effect and decompose the original machined surface topography at multiple scales. The characteristic surface topography representing the relative vibration between the cutter and the workpiece through feature identification is selected. In addition, the spatial spectrum analysis of the extracted profile is carried out. The decimal part of the frequency ratio that has an important effect on the shape of the contour can be accurately identified through contour extraction and spatial spectrum analysis. The decomposition results of simulation and experimental surface morphology demonstrate the validity of the improved BEMD algorithm in realizing the relative vibration identification between the cutter and the workpiece.

关键词： bidimensional empirical mode decomposition spatial spectrum analysis boundary effect vibration identification surface topography

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Changes in public trust in physicians: empirical evidence from China

Dahai Zhao, Zhiruo Zhang

《医学前沿（英文）》 2019年第13卷第4期页码 504-510 doi: 10.1007/s11684-018-0666-4

摘要： Studies examining the trends in public trust in physicians have provided a considerable amount of valuable policy implications for policymakers compared with cross-sectional studies on this topic in many countries. This study investigated changes in public trust in physicians in China based on two cross-sectional national surveys conducted in 2011 and 2016 and identified the determinants of these changes. The results indicated 83.4% of respondents in 2011 reported trust or strong trust in physicians in China, which decreased to 64.2% by 2016. The results of ordinal logistic regression demonstrated that public trust in physicians in China had decreased significantly from 2011 to 2016 ( <0.001) after adjusting for other independent variables. Self-reported health status, self-rated happiness, and self-identified social class were all associated positively with public trust in physicians in China. The results also confirmed that decreasing public satisfaction with the most recent treatment experience was the major determinant of decreasing public trust in physicians in China. The findings of this study suggest that decreasing public trust in physicians deserves considerable attention from national policymakers and that improving satisfaction with treatment experiences would be the most effective strategy for enhancing public trust in physicians in China.

关键词： trust in physicians public trust physician-patient relationship health system performance

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relationship of industrial agglomeration and low-carbon economy considering spatiotemporal differentiation: An empirical

《工程管理前沿（英文）》 2023年第10卷第2期页码 285-299 doi: 10.1007/s42524-022-0197-1

摘要： Although China’s construction machinery thrives to meet the needs of construction, a number of challenges still remain to be overcome, such as lack of thorough knowledge of regional disparities and several limitations in terms of carbon emissions and economic development. Meanwhile, a low-carbon economy was proposed and implemented in China. This research aims to investigate the differences in industrial agglomeration of construction machineries and further explore the relationship between industrial agglomeration and low-carbon economy. On this basis, spatiotemporal analysis was performed to evaluate the levels of industrial agglomeration in different regions based on the situations of China’s construction machinery industry. Furthermore, this study explored the interaction between industrial agglomeration and low-carbon economy utilizing the coupling coordination analysis method. Results showed that the coupling coordination of the two subsystems was extremely unbalanced in 2006, and it maintained an increasing trend, reaching a relatively high level in 2018. Finally, suggestions, such as establishing a policy guarantee system and implementing variable policies in different regions, were proposed to provide guidelines for the government decision-making and promote the sustainable development of China’s construction machinery industry.

关键词： spatiotemporal differentiation industrial agglomeration low-carbon economy construction machinery industry empirical study

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连轧张力公式的实验验证和分析

张进之,赵厚信,王喆,王保罗

《中国工程科学》 2008年第10卷第4期页码 73-77

摘要：

连轧张力公式是连轧理论和实践的核心问题，该问题国内外都有大量的研究，20世纪60年代笔者推导了连轧张力微分方程、多机架动态张力公式、稳态张力公式，理论上已作过深入、广泛的分析讨论。日本在20世纪70年代对连轧张力公式进行了理论上的推导和实验验证，特别是浅川基男等人的连轧实验结果更为重要。为此引用了浅川基男的实验数据和宝钢2 050 mm热连轧机上的实测数据，验证了连轧张力公式。

关键词：连轧张力公式实验验证解析解定常性

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An Empirical Study on the Generation Mechanism of NIMBY Conflicts of Construction Projects

Guang-she Jia,Song-yu Yan,Wen-jun Wang,Ralf Müller,Chen Lin

《工程管理前沿（英文）》 2016年第3卷第1期页码 39-49 doi: 10.15302/J-FEM-2016015

摘要： In the highly overlapped contexts of urbanization and social transformation, and with the advent of the “Risk Society,” the social issues, called “Not in My Back Yard (NIMBY)” conflicts, caused by the construction or operation of the NIMBY projects have become a serious problem in China. Hence, it is in urgent need to find out the influencing factors and discover the generation mechanism of the NIMBY conflicts. From the perspective of social conflict theory, the authors built a process model of the NIMBY conflicts on the basis of identifying stakeholders and analyzing their interest interaction. Thereafter, the authors conducted a questionnaire survey, followed by exploratory factor analysis (EFA) revealing the underlying influencing factors of the NIMBY conflicts. Finally, they performed the confirmatory analysis method of Structural Equation Modeling to test the preliminary research hypothesis of the model and its interaction path in AMOS 18.0, with the results showing that unequal exchange and consensus mobilization will contribute to the formation of common consciousness of the opposition party, the opposition party’s common consciousness and action mobilization affects the generation of social conflicts. The process model reveals the generation mechanism of the NIMBY conflicts, and it facilitates further investigations in the governance of the NIMBY conflicts.

关键词： NIMBY conflicts social conflict construction projects mechanism empirical study

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An Empirical Study on the Internal Control Efficiency of Listed Engineering Companies

Zhi-wen Wang,Jing Tong

《工程管理前沿（英文）》 2015年第2卷第2期页码 159-164 doi: 10.15302/J-FEM-2015026

摘要： The authors carried out an empirical study on the internal control efficiency of publically listed engineering companies in China. This study presents an exploration of the relationship of independent director ratios, audit committee quality and auditor independence with the internal control efficiency of publically listed engineering companies and forward suggestions and recommendations on raising the internal control efficiency of publically listed engineering companies.

关键词： internal control efficiency board of directors independent directors audit committee

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Empirical models and design codes in prediction of modulus of elasticity of concrete

Behnam VAKHSHOURI, Shami NEJADI

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 38-48 doi: 10.1007/s11709-018-0479-1

摘要： Modulus of Elasticity (MOE) is a key parameter in reinforced concrete design. It represents the stress-strain relationship in the elastic range and is used in the prediction of concrete structures. Out of range estimation of MOE in the existing codes of practice strongly affect the design and performance of the concrete structures. This study includes: (a) evaluation and comparison of the existing analytical models to estimating the MOE in normal strength concrete, and (b) proposing and verifying a new model. In addition, a wide range of experimental databases and empirical models to estimate the MOE from compressive strength and density of concrete are evaluated to verification of the proposed model. The results show underestimation of MOE of conventional concrete in majority of the existing models. Also, considering the consistency between density and mechanical properties of concrete, the predicted MOE in the models including density effect, are more compatible with the experimental results.

关键词： modulus of elasticity normal strength normal weight concrete empirical models design codes compressive strength density

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ANN-based empirical modelling of pile behaviour under static compressive loading

Abdussamad ISMAIL

《结构与土木工程前沿（英文）》 2018年第12卷第4期页码 594-608 doi: 10.1007/s11709-017-0446-2

摘要： Artificial neural networks have been widely used over the past two decades to successfully develop empirical models for a variety of geotechnical problems. In this paper, an empirical model based on the product-unit neural network (PUNN) is developed to predict the load-deformation behaviour of piles based SPT values of the supporting soil. Other parameters used as inputs include particle grading, pile geometry, method of installation as well as the elastic modulus of the pile material. The model is trained using full-scale pile loading tests data retrieved from FHWA deep foundations database. From the results obtained, it is observed that the proposed model gives a better simulation of pile load-deformation curves compared to the Fleming’s hyperbolic model and t-z approach.

关键词： piles in compression load-deformation behaviour product-unit neural network

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Novel empirical model for predicting residual flexural capacity of corroded steel reinforced concrete

Zhao-Hui LU, Hong-Jun WANG, Fulin QU, Yan-Gang ZHAO, Peiran LI, Wengui LI

《结构与土木工程前沿（英文）》 2020年第14卷第4期页码 888-906 doi: 10.1007/s11709-020-0637-0

摘要： In this study, a total of 177 flexural experimental tests of corroded reinforced concrete (CRC) beams were collected from the published literature. The database of flexural capacity of CRC beam was established by using unified and standardized experimental data. Through this database, the effects of various parameters on the flexural capacity of CRC beams were discussed, including beam width, the effective height of beam section, ratio of strength between longitudinal reinforcement and concrete, concrete compressive strength, and longitudinal reinforcement corrosion ratio. The results indicate that the corrosion of longitudinal reinforcement has the greatest effect on the residual flexural capacity of CRC beams, while other parameters have much less effect. In addition, six available empirical models for calculating the residual flexural strength of CRC beams were also collected and compared with each other based on the established database. It indicates that though five of six existing empirical models underestimate the flexural capacity of CRC beams, there is one model overestimating the flexural capacity. Finally, a newly developed empirical model is proposed to provide accurate and effective predictions in a large range of corrosion ratio for safety assessment of flexural failure of CRC beams confirmed by the comparisons.

关键词： CRC beams flexural capacity steel corrosion database empirical models

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以土体应力状态计算边坡安全系数的方法

王国体

《中国工程科学》 2006年第8卷第12期页码 80-84

摘要：

土坡的稳定分析一直是沿着条分法的思路发展的。由于对土体应力状态条件的忽视和条分法本身的缺陷，使得条分法得到的安全系数在工程中的应用面临激烈的挑战。土体不同条件下的应力状态表现为K₀效应和变化，它对坡体的安全度影响不可忽视。笔者以考虑土体应力状态为条件，应用土的库伦强度定律和摩尔-库伦准则，推导出平面土坡的安全系数计算公式，与条分法的安全系数对比结果说明这种方法具有概念明确、计算简便、定性可靠的重要特点，可以直接提供于工程应用和参考。

关键词：侧应力系数K₀ 初始应力状态稳定安全系数公式

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Empirical analysis of the Environmental Kuznets Curve in agrochemicals

Fei LI,Suocheng DONG,Fujia LI,Libiao YANG

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 276-287 doi: 10.1007/s11783-014-0700-y

摘要： As the largest contributor to water impairment, agriculture-related pollution has attracted the attention of scientists as well as policy makers, and quantitative information is being sought to focus and advance the policy debate. This study applies the panel unit root, heterogeneous panel cointegration, and panel-based dynamic ordinary least squares to investigate the Environmental Kuznets Curve on environmental issues resulting from use of agricultural synthetic fertilizer, pesticide, and film for 31 provincial economies in mainland China from 1989 to 2009. The empirical results indicate a positive long-run co-integrated relationship between the environmental index and real GDP per capita. This relationship takes on the inverted U-shaped Environmental Kuznets Curve, and the value of the turning point is approximately 10,000–13,000, 85,000–89,000 and over 160,000 CNY, for synthetic fertilizer nitrogen indicator, fertilizer phosphorus indicator and pesticide indicator, respectively. At present, China is subject to tremendous environmental pressure and should assign more importance to special agriculture-related environmental issues.

关键词： Environmental Kuznets Curve agrochemical China

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Lingguizhugan Decoction, a Chinese herbal formula, improves insulin resistance in overweight/obese subjects

《医学前沿（英文）》 2022年第16卷第5期页码 745-759 doi: 10.1007/s11684-021-0880-3

摘要： Lingguizhugan Decoction (LGZG) has been investigated in basic studies, with satisfactory effects on insulin resistance in non-alcoholic fatty liver disease (NAFLD). This translational approach aimed to explore the effect and underlying mechanism of LGZG in clinical setting. A randomized, double-blinded, placebo-controlled trial was performed. A total of 243 eligible participants with NAFLD were equally allocated to receive LGZG (two groups: standard dose and low dose) or placebo for 12 weeks on the basis of lifestyle modifications. The primary efficacy variable was homeostasis model assessment of insulin resistance (HOMA-IR). Analyses were performed in two populations in accordance with body mass index (BMI; overweight/obese, BMI ≥ 24 kg/m²; lean, BMI < 24 kg/m ²). For overweight/obese participants, low-dose LGZG significantly decreased their HOMA-IR level compared with placebo (−0.19 (1.47) versus 0.08 (1.99),P = 0.038). For lean subjects, neither dose of LGZG showed a superior effect compared with placebo. Methylated DNA immunoprecipitation sequencing and real-time qPCR found that the DNA N6-methyladenine modification levels of protein phosphatase 1 regulatory subunit 3A (PPP1R3A) and autophagy related 3 (ATG3) significantly increased after LGZG intervention in overweight/obese population. Low-dose LGZG effectively improved insulin resistance in overweight/obese subjects with NAFLD. The underlying mechanism may be related to the regulation of DNA N6-methyladenine modification of PPP1R3A and ATG3. Lean subjects may not be a targeted population for LGZG.

关键词： insulin resistance non-alcoholic fatty liver disease Chinese herbal medicine randomized controlled trial DNA N6-methyladenine modification