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Efficiency evaluation of government investment for air pollution control in city clusters: A case from the Beijing–Tianjin–Hebei areas in China

《工程管理前沿(英文)》   页码 612-624 doi: 10.1007/s42524-023-0269-x

摘要: Air pollution poses a significant threat to human health, particularly in urban areas with high levels of industrial activities. In China, the government plays a crucial role in managing air quality through the Air Pollution Prevention and Control Action Plan. The government provides direct financial support and guides the investment direction of social funds to improve air quality. While government investment has led to improvements in air quality across China, concerns remain regarding the efficiency of such large-scale investments. To address this concern, we conducted a study using a three-stage data envelopment analysis (DEA)-Malmquist model to assess the efficiency of government investment in improving air quality in China. Our analysis revealed regional disparities and annual dynamic changes. Specifically, we focused on the Beijing–Tianjin–Hebei areas as a case study, as the investment primarily targeted industrial activities in urban areas with the goal of improving living conditions for urban residents. The results demonstrate significant differences in investment efficiency between regions. Beijing exhibits relatively high investment efficiency, while cities in Hebei Province require improvement. We identified scale inefficiency, which refers to the ratio of air pollutant reduction to financial investment, as the main factor contributing to regional disparities. However, we found that increasing the total investment scale can help mitigate this effect. Furthermore, our study observed positive but fluctuating annual changes in investment efficiency within this city cluster from 2014 to 2018. Investment-combined technical efficiency, which represents the investment strategy, is the main obstacle to improving yearly investment efficiency. Therefore, in addition to promoting investment strategies at the individual city level, it is crucial to enhance coordination and cooperation among cities to improve the investment efficiency of the entire city cluster. Evaluating the efficiency of government investment and understanding its influencing factors can guide future investment measures and directions. This knowledge can also support policymaking for other projects involving substantial investments.

关键词: investment efficiency     government investment     air pollution control     three-stage DEA-Malmquist model    

Removal of odors and VOCs in municipal solid waste comprehensive treatment plants using a novel three-stage

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1421-7

摘要:

A novel three-stage integrated biofilter (TSIBF) composed of acidophilic bacteria reaction segment (ABRS), fungal reaction segment (FRS) and heterotrophic bacteria reaction segment (HBRS) was constructed for the treatment of odors and volatile organic compounds (VOCs)from municipal solid waste (MSW) comprehensive treatment plants. The performance, counts of predominant microorganisms, and bioaerosol emissions of a full-scale TSIBF system were studied. High and stable removal efficiencies of hydrogen sulfide, ammonia and VOCs could be achieved with the TSIBF system, and the emissions of culturable heterotrophic bacteria, fungi and acidophilic sulfur bacteria were relatively low.

关键词: Biofiltration     Multi-stage biofilter     Volatile organic compounds     Waste gas treatment     Bioaerosol emissions    

Sustainability performance analysis of environment innovation systems using a two-stage network DEA model

《工程管理前沿(英文)》   页码 425-438 doi: 10.1007/s42524-022-0205-5

摘要: The term environmental innovation system refers to an innovation network composed of enterprises, universities, and research institutions involved in the development and diffusion of environmental technology, with the participation of a government. An environmental innovation system not only exerts important impact on the achievement of carbon neutrality but also affects social and economic activities. Investigations on environmental innovation system performance constantly assume a single-stage independent system while ignoring its internal structure. However, such systems are composed of environmental innovation research and development (R&D) and environmental innovation conversion subsystems. A two-stage data envelopment analysis (DEA) model is developed in this study to analyze the efficiency of Chinese regional environmental innovation system by opening the “black box” and considering shared resources. Empirical results indicated that China presents high overall environmental innovation efficiency although some regions need to improve. Regions with low efficiencies in both environmental innovation R&D (EIR) and environmental innovation conversion (EIC) subsystems should expand their investment in and strengthen the management of environmental innovation resources. Regions with low EIR efficiency should improve the absorption and transformation of environmental innovation achievements. Regions with low EIC efficiency should increase investment in the commercialization of environmental innovation achievements and encourage green economy industries, such as new energy, art, tourism, and environmental protection.

关键词: data envelopment analysis     environmental efficiency     environmental innovation system     shared resources     two-stage structure    

Theoretical modeling and experimental verifications of the single-compressor-driven three-stage Stirling-type

Haizheng DANG, Dingli BAO, Zhiqian GAO, Tao ZHANG, Jun TAN, Rui ZHA, Jiaqi LI, Ning LI, Yongjiang ZHAO, Bangjian ZHAO

《能源前沿(英文)》 2019年 第13卷 第3期   页码 450-463 doi: 10.1007/s11708-018-0569-8

摘要: This paper establishes a theoretical model of the single-compressor-driven (SCD) three-stage Stirling-type pulse tube cryocooler (SPTC) and conducts experimental verifications. The main differences between the SCD type and the multi-compressor-driven (MCD) cryocooler are analyzed, such as the distribution of the input acoustic power in each stage and the optimization of the operating parameters, in which both advantages and difficulties of the former are stressed. The effects of the dynamic temperatures are considered to improve the accuracy of the simulation at very low temperatures, and a specific simulation example aiming at 10 K is given in which quantitative analyses are provided. A SCD three-stage SPTC is developed based on the theoretical analyses and with a total input acoustic power of 371.58 W, which reaches a no-load temperature of 8.82 K and can simultaneously achieve the cooling capacities of 2.4 W at 70 K, 0.17 W at 25 K, and 0.05 W at 10 K. The performance of the SCD three-stage SPTC is slightly poorer than that of its MCD counterpart developed in the same laboratory, but the advantages of lightweight and compactness make the former more attractive to practical applications.

关键词: single-compressor-driven     three-stage     Stirling-type pulse tube cryocooler     theoretical modeling     experimental verification    

Methods and applications of DEA cross-efficiency: Review and future perspectives

Jie WU, Jiasen SUN, Liang LIANG

《工程管理前沿(英文)》 2021年 第8卷 第2期   页码 199-211 doi: 10.1007/s42524-020-0133-1

摘要: The field of engineering management usually involves evaluation issues, such as program selection, team performance evaluation, technology selection, and supplier evaluation. The traditional self-evaluation data envelopment analysis (DEA) method usually exaggerates the effects of several inputs or outputs of the evaluated decision-making unit (DMU), resulting in unrealistic results. To address this problem, scholars have proposed the cross-efficiency evaluation (CREE) method. Compared with the DEA method, CREE can rank DMUs more completely by using reasonable weights. With the extensive application of this technique, several problems, such as non-unique weights and non-Pareto optimal results, have arisen in CREE methods. Therefore, the improvement of CREE has attracted the attention of many scholars. This paper reviews the theory and applications of CREE, including the non-uniqueness problem, the aggregation of cross-efficiency data, and applications in engineering management. It also discusses the directions for future research on CREE.

关键词: cross-efficiency evaluation     efficiency     secondary goal model     aggregation     review    

Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

《环境科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 313-319 doi: 10.1007/s11783-009-0025-4

摘要: This investigation was carried out to establish a new domestic landfill gas (LFG) generation rate model that takes into account the impact of leachate recirculation. The first-order kinetics and two-stage reaction (FKTSR) model of the LFG generation rate includes mechanisms of the nutrient balance for biochemical reaction in two main stages. In this study, the FKTSR model was modified by the introduction of the outflow function and the organic acid conversion coefficient in order to represent the in-situ condition of nutrient loss through leachate. Laboratory experiments were carried out to simulate the impact of leachate recirculation and verify the modified FKTSR model. The model calibration was then calculated by using the experimental data. The results suggested that the new model was in line with the experimental data. The main parameters of the modified FKTSR model, including the LFG production potential (), the reaction rate constant in the first stage (), and the reaction rate constant in the second stage () of 64.746 L, 0.202 d, and 0.338 d, respectively, were comparable to the old ones of 42.069 L, 0.231 d, and 0.231 d. The new model is better able to explain the mechanisms involved in LFG generation.

关键词: landfill gas (LFG)     generation rate model     first-order kinetics     two-stage reaction     outflow function    

一种流水车间批量调度的高效计算三阶段优化方法 Research Articles

Hai-yan WANG, Fu ZHAO, Hui-min GAO, John W. SUTHERLAND

《信息与电子工程前沿(英文)》 2019年 第20卷 第7期   页码 1002-1020 doi: 10.1631/FITEE.1700457

摘要: 在工件含批量生产任务情况下如何进行最佳生产调度是一个重要的生产计划问题。通常将批量工件划分为子批处理(称为分批优化)。若子批数较大,则会大大增加工件完成时间的计算复杂性。现有研究未能考虑此类计算时间问题。本文考虑可变子批、准备时间以及子批批量约束(传输子批批量受传输设备容量限制),提出一种求解n个工件、m台机器流水车间分批优化调度方法。所提方法包含3个阶段:初始批量划分、基于生产周期/总流程时间指标快速评价法的工件排序优化、分批传输方案调整。为验证3阶段优化方法的有效性,采用5个标准数据集进行测试。实验结果表明,所提方法能节省大量计算时间,尤其对大规模问题能提供更优解。

关键词: 批量流;流水车间调度;传输子批;可变批量;批量约束;差分进化    

数据包络分析法(DEA)的研究与应用

李美娟,陈国宏

《中国工程科学》 2003年 第5卷 第6期   页码 88-94

摘要:

叙述了数据包络分析法(DEA)的思想、模型和应用步骤,总结了近20多年来DEA方法的发展、主要应用领域——DEA方法的主要研究成果,并对该领域的进一步研究提出了一些想法和展望

关键词: 数据包络分析法(DEA    决策单元     相对有效性     研究趋势    

Probabilistic model for vessel-bridge collisions in the Three Gorges Reservoir

Bo GENG , Hong WANG , Junjie WANG ,

《结构与土木工程前沿(英文)》 2009年 第3卷 第3期   页码 279-285 doi: 10.1007/s11709-009-0044-z

摘要: Based on a field observation on vessel transit path of three bridges over the Yangtze River in the Three Gorges Reservoir, and an analysis of the geometric probabilistic model of transiting vessels in collision probability calculation, the aberrancy angle and vessel velocity probabilistic model related with impact force, a probabilistic model is established and also verified by goodness-of-fit test. The vessel transit path distribution can be expressed by the normal distribution model. For the Three Gorges Reservoir, the mean and standard deviation adopt 0.2 and 0.1, respectively ( is the channel width). The aberrancy angle distribution of vessels accepts maximum I distribution model, and its distribution parameters can be taken as 0.314 and 4.354. The velocity distribution of up-bound and down-bound vessels can also be expressed by the normal distribution model.

关键词: vessel-bridge collision     probabilistic model     parameter statistics    

有固相析出的多效两段蒸发系统模型与过程模拟

李玲,阮奇

《中国工程科学》 2008年 第10卷 第10期   页码 54-60

摘要:

建立了带有冷凝水闪蒸的有固相析出的多效两段蒸发系统的常规设计数学模型,模型将系统的相平衡关系用回归式表达,使模型可以用计算机编程求解,避免了手工计算结合查相图的烦琐的计算过程;利用矩阵方程具有结构清晰和高度模块化的特点,将系统的物料衡算和热量衡算方程组写成矩阵方程的形式,只要保留或舍弃矩阵方程中的相关块矩阵,模型就能代表没有冷凝水闪蒸或没有固相析出的多效两段蒸发系统常规设计模型;采用迭代法结合矩阵法来求解模型,算例表明,冷凝水闪蒸对多效两段蒸发系统是有效的节能措施,算法收敛速度快、收敛稳定性好。

关键词: 固相析出     多效两段蒸发数学模型     冷凝水闪蒸    

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)    

A data envelopment analysis of agricultural technical efficiency of Northwest Arid Areas in China

Yubao WANG, Lijie SHI, Haojie ZHANG, Shikun SUN

《农业科学与工程前沿(英文)》 2017年 第4卷 第2期   页码 195-207 doi: 10.15302/J-FASE-2017153

摘要: Severe resource shortage and waste of resource in agricultural production make it necessary to assess efficiency to increase productivity with high efficiency and ensure sustainable agricultural development. This paper adopted an input-oriented data envelopment analysis (DEA) method with the assumption of variable returns to scale to evaluate agricultural production efficiency of 100 major irrigation districts in Northwest China in 2010. Major findings of this paper were as follows: firstly, the average value of total technical efficiency, pure technical efficiency and scale efficiency of those irrigation districts in Northwest China were 0.770, 0.825 and 0.931, respectively; secondly, 30% of irrigation districts were technically efficient, while 42% and 32% of them showed pure technical and scale efficiency respectively. Among inefficient decision-making units, total technical efficiency score varied from 0.313 to 0.966, showing significant geographical differences, but geographical differences of pure technical efficiency was more consistent with that of total technical efficiency; thirdly, input redundancy was evident. Inputs of agricultural population, irrigation area, green water, blue water, consumption of fertilizer and agricultural machinery could be reduced by 34.88%, 40.19%, 43.85%, 47.10%, 41.53% and 42.21% respectively without reducing agricultural outputs. Furthermore, irrigation area, green water and blue water had relatively high slack movement though Northwest China which is short of water resources. Based on these results, this paper drew the following conclusions: First, there is huge potential for Northwest China to improve its agricultural production efficiency, and agro-technology not input scale had greater influence on improvement. Second, farmers needed proper guidance in order to reduce agricultural inputs and it is time to centralize agricultural management for overall agricultural inputs regulation and control.

关键词: agricultural production efficiency     DEA model     input redundancy     irrigation districts     Northwest Arid Areas in China    

An efficient two-stage approach for structural damage detection using meta-heuristic algorithms and groupmethod of data handling surrogate model

Hamed FATHNEJAT, Behrouz AHMADI-NEDUSHAN

《结构与土木工程前沿(英文)》 2020年 第14卷 第4期   页码 907-929 doi: 10.1007/s11709-020-0628-1

摘要: In this study, the performance of an efficient two-stage methodology which is applied in a damage detection system using a surrogate model of the structure has been investigated. In the first stage, in order to locate the damage accurately, the performance of the modal strain energy based index for using different numbers of natural mode shapes has been evaluated using the confusion matrix. In the second stage, to estimate the damage extent, the sensitivity of most used modal properties due to damage, such as natural frequency and flexibility matrix is compared with the mean normalized modal strain energy (MNMSE) of suspected damaged elements. Moreover, a modal property change vector is evaluated using the group method of data handling (GMDH) network as a surrogate model during damage extent estimation by optimization algorithm; in this part of methodology, the performance of the three popular optimization algorithms including particle swarm optimization (PSO), bat algorithm (BA), and colliding bodies optimization (CBO) is examined and in this regard, root mean square deviation ( ) based on the modal property change vector has been proposed as an objective function. Furthermore, the effect of noise in the measurement of structural responses by the sensors has also been studied. Finally, in order to achieve the most generalized neural network as a surrogate model, GMDH performance is compared with a properly trained cascade feed-forward neural network (CFNN) with log-sigmoid hidden layer transfer function. The results indicate that the accuracy of damage extent estimation is acceptable in the case of integration of PSO and MNMSE. Moreover, the GMDH model is also more efficient and mimics the behavior of the structure slightly better than CFNN model.

关键词: two-stage method     modal strain energy     surrogate model     GMDH     optimization damage detection    

Three-dimensional numerical simulation of flow in trapezoidal cutthroat flumes based on FLOW-3D

Danjie RAN, Wene WANG, Xiaotao HU

《农业科学与工程前沿(英文)》 2018年 第5卷 第2期   页码 168-176 doi: 10.15302/J-FASE-2018217

摘要: To solve the common problem of flumes flow-measurement accuracy without sacrificing water head, a new type of trapezoidal cutthroat flume to measure the discharge in terminal trapezoidal channels is presented. Using the computational fluid dynamic method, three-dimensional flow fields in trapezoidal cutthroat flumes were simulated using the RNG three-dimensional turbulence model along with the TruVOF technique. Simulations were performed for 12 working conditions, with discharges up to 0.075 m ·s to determine hydraulic performance. Experimental data for the trapezoidal cutthroat flume in terminal trapezoidal channel were also obtained to validate the simulation results. Velocity distribution of the flume obtained from simulation analyses were compared with observed results based on time-averaged flow field and comparison yielded a solid agreement between results from the two methods, with relative error below 10%. The results indicated that the Froude number and the longitudinal average velocity increased along the convergence section and decreased in the divergent section. In the upper throat, the Froude number was less than 0.5, which meets the water measurement requirement, and the critical flow appeared near the throat section. The maximum water head loss of the trapezoidal cutthroat flume was less than 9% of the total head, compared to the rectangular cutthroat flume, and head loss of trapezoidal cutthroat flume was significantly less. Regression models developed for upstream depth versus discharge under different working conditions were satisfactory, with a relative error of less than 2.06%, which meets the common requirements of flow measurement in irrigation areas. It was concluded that trapezoidal cutthroat flumes can improve flow-measurement accuracy without sacrificing water head.

关键词: distribution of velocity     Froude number     head loss     stage-discharge relationship     trapezoidal cutthroat flume    

General closed-form inverse kinematics for arbitrary three-joint subproblems based on the product ofexponential model

《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0681-7

摘要: The inverse kinematics problems of robots are usually decomposed into several Paden–Kahan subproblems based on the product of exponential model. However, the simple combination of subproblems cannot solve all the inverse kinematics problems, and there is no common approach to solve arbitrary three-joint subproblems in an arbitrary postural relationship. The novel algebraic geometric (NAG) methods that obtain the general closed-form inverse kinematics for all types of three-joint subproblems are presented in this paper. The geometric and algebraic constraints are used as the conditions precedent to solve the inverse kinematics of three-joint subproblems. The NAG methods can be applied in the inverse kinematics of three-joint subproblems in an arbitrary postural relationship. The inverse kinematics simulations of all three-joint subproblems are implemented, and simulation results indicating that the inverse solutions are consistent with the given joint angles validate the general closed-form inverse kinematics. Huaque III minimally invasive surgical robot is used as the experimental platform for the simulation, and a master–slave tracking experiment is conducted to verify the NAG methods. The simulation result shows the inverse solutions and six sets given joint angles are consistent. Additionally, the mean and maximum of the master–slave tracking experiment for the closed-form solution are 0.1486 and 0.4777 mm, respectively, while the mean and maximum of the master–slave tracking experiment for the compensation method are 0.3188 and 0.6394 mm, respectively. The experiments results demonstrate that the closed-form solution is superior to the compensation method. The results verify the proposed general closed-form inverse kinematics based on the NAG methods.

关键词: inverse kinematics     Paden–Kahan subproblems     three-joint subproblems     product of exponential     closed-form solution    

标题 作者 时间 类型 操作

Efficiency evaluation of government investment for air pollution control in city clusters: A case from the Beijing–Tianjin–Hebei areas in China

期刊论文

Removal of odors and VOCs in municipal solid waste comprehensive treatment plants using a novel three-stage

期刊论文

Sustainability performance analysis of environment innovation systems using a two-stage network DEA model

期刊论文

Theoretical modeling and experimental verifications of the single-compressor-driven three-stage Stirling-type

Haizheng DANG, Dingli BAO, Zhiqian GAO, Tao ZHANG, Jun TAN, Rui ZHA, Jiaqi LI, Ning LI, Yongjiang ZHAO, Bangjian ZHAO

期刊论文

Methods and applications of DEA cross-efficiency: Review and future perspectives

Jie WU, Jiasen SUN, Liang LIANG

期刊论文

Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

期刊论文

一种流水车间批量调度的高效计算三阶段优化方法

Hai-yan WANG, Fu ZHAO, Hui-min GAO, John W. SUTHERLAND

期刊论文

数据包络分析法(DEA)的研究与应用

李美娟,陈国宏

期刊论文

Probabilistic model for vessel-bridge collisions in the Three Gorges Reservoir

Bo GENG , Hong WANG , Junjie WANG ,

期刊论文

有固相析出的多效两段蒸发系统模型与过程模拟

李玲,阮奇

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

A data envelopment analysis of agricultural technical efficiency of Northwest Arid Areas in China

Yubao WANG, Lijie SHI, Haojie ZHANG, Shikun SUN

期刊论文

An efficient two-stage approach for structural damage detection using meta-heuristic algorithms and groupmethod of data handling surrogate model

Hamed FATHNEJAT, Behrouz AHMADI-NEDUSHAN

期刊论文

Three-dimensional numerical simulation of flow in trapezoidal cutthroat flumes based on FLOW-3D

Danjie RAN, Wene WANG, Xiaotao HU

期刊论文

General closed-form inverse kinematics for arbitrary three-joint subproblems based on the product ofexponential model

期刊论文