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Internal incentives and operations strategies for the water-saving supply chain with cap-and-trade regulation

Zhisong CHEN, Li FANG, Huimin WANG

《工程管理前沿(英文)》 2019年 第6卷 第1期   页码 87-101 doi: 10.1007/s42524-019-0006-7

摘要:

Faced with the rapid development of modern industries of agriculture, manufacturing, and services, water resources are becoming increasingly scarce. Industries with high water consumption are generally regulated by the government’s water cap-and-trade (CAT) regulation to solve the contradiction between the limited water supply and the rapid growing water demand. Supply chain equilibrium and coordination models under the benchmark scenario without water saving and CAT regulation, water-saving supply chain equilibrium and coordination models under the scenario without/with CAT regulation are developed, analyzed and compared. The corresponding numerical and sensitivity analyses for all models are conducted and compared, and the managerial insights and policy recommendations are summarized in this article. The results indicate that (1) Conducting water saving could improve effectively the operational performance of the water-saving supply chain under the scenario without/with CAT regulation. (2) The coordination strategy based on the revenue sharing contract could efficiently coordinate the water-saving supply chain, enhance water consumption reduction rate, and improve the operational performance of the water-saving supply chain. (3) The implementation of CAT regulation enhances effectively water-consumption-reduction in the water-saving supply chain and improves the operational performance of water-saving supply chain. (4) Simultaneous implementation of CAT regulation by the government and adopting coordination strategy by the water-saving supply chain would be superior to any other scenarios/strategies. (5) A suitable water cap based on the industrial average water consumption and historical water consumption data are beneficial for constructing reasonable and effective incentive mechanism. (6) A higher marginal trade price could induce more reduction in water consumption and create better operational performance for the manufacturer and water-saving supply chain, both under the equilibrium and coordination strategies.

关键词: water-saving supply chain     equilibrium     coordination     internal incentive     cap and trade regulation    

Cylindrical particulate internal flows: A review

Lizhong HUANG, Xiang GAO, Jianzhong LIN

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 385-393 doi: 10.1007/s11465-012-0354-z

摘要:

The study of cylindrical particulate internal flows has wide industrial applicability hence received much attention. This article reviews the cylindrical particulate internal flows over the past twenty years. The research is related to the cylindrical particulate flows in the straight channel, curved channel and rotational channel. Finally, several open research issues have been identified.

关键词: cylindrical particulate flow     internal flow    

Current progress on internal medicine in China—2006 Part I

YAO Dingkang, ZHU Liang, ZHAO Xue, MEI Changlin

《医学前沿(英文)》 2007年 第1卷 第3期   页码 235-247 doi: 10.1007/s11684-007-0046-y

摘要: The growing interest has been placed in the current state of Chinaºs internal medicine from all over the world. Many data of internal medicine in China were collected by searching through some of the most prominent medical magazines published in China in 2006. Because there are many researches on the field of internal medicine, just some representative reports focusing on this topic were selected in this paper. In part I of this study, a summary of the advances made in cardiology, respiration diseases, and gastroenterology was presented.

关键词: internal medicine     Chinaºs internal     respiration     gastroenterology     cardiology    

Unified cycle model of a class of internal combustion engines and their optimum performance characteristics

Shiyan ZHENG

《能源前沿(英文)》 2011年 第5卷 第4期   页码 367-375 doi: 10.1007/s11708-011-0170-x

摘要: The unified cycle model of a class of internal combustion engines is presented, in which the influence of the multi-irreversibilities mainly resulting from the adiabatic processes, finite-time processes and heat leak loss through the cylinder wall on the performance of the cycle are taken into account. Based on the thermodynamic analysis method, the mathematical expressions of the power output and efficiency of the cycle are calculated and some important characteristic curves are given. The influence of the various design parameters such as the high-low pressure ratio, the high-low temperature ratio, the compression and expansion isentropic efficiencies etc. on the performance of the cycle is analyzed. The optimum criteria of some important parameters such as the power output, efficiency and pressure ratio are derived. The results obtained from this unified cycle model are very general and useful, from which the optimal performance of the Atkinson, Otto, Diesel, Dual and Miller heat engines and some new heat engines can be directly derived.

关键词: internal combustion engine     irreversibility     power output     efficiency     optimization    

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    

Quantitative research of incentive effects of heat-metering policy on energy-saving behavior in Tianjin

Jihong LING,Haitao MA,HuiZhu YU,Jincheng XING

《能源前沿(英文)》 2014年 第8卷 第4期   页码 504-512 doi: 10.1007/s11708-014-0332-8

摘要: To promote energy efficiency and emission reduction, the Chinese government has invested large amounts of resources in heat-metering reform over the past decade. However, heat-metering, which can reduce energy consumption by 15% at least in developed countries, is still not well known in China. This paper quantitatively analyzed the arousal effect of heat-metering policy on occupancy behavior regarding energy saving utilizing statistics method based on measured data of heating energy consumption of approximately 20000 users from 2008 to 2012 in Tianjin. The statistical data showed significant difference on energy consumption between users based on metering and based on area. The energy-saving rate in the heating season increased significantly from 4.11% in 2008–2009 to 10.27% in 2011–2012 as the implement of the heat-metering policy. The difference in energy-saving according to various outdoor temperatures showed that the energy-saving of occupancy behavior was more significant in a warm season than in a cold season. It also showed that the impact of heat-metering policy would be more pronounced in generally insulated buildings (15.55%) than in better insulated units (6.45%). Besides, this paper proposed some feasible suggestions for the formulation and implementation of heat-metering policy in northern heating areas of China.

关键词: heat-metering     occupancy behavior     heating energy consumption     policy    

Embankment dam foundation analysis for the decrease of internal erosion likelihood

Marc SMITH

《结构与土木工程前沿(英文)》 2012年 第6卷 第4期   页码 431-436 doi: 10.1007/s11709-012-0183-5

摘要: A zoned embankment dam is founded on clay underlain by a sand deposit. Major seepage phenomena were noticed in the foundation downstream from the dam where the vertical seepage forces in the sand layer were expected to exceed the downward forces due to the overlying clay. Modern technologies were applied to delineate critical zones to help design optimal rehabilitation measures. A global electromagnetic survey was carried out to detect and map the main sources, pathways and exits of seepage. Based on these global findings, a more detailed analysis was then conducted to identify zones where thickness of the foundation clay is minimal, pore pressures in sand are higher and thus where the factor of safety against uplift is lower and internal erosion is more likely to occur. Clay thickness evaluation required the determination of land surface as well as clay-sand contact elevations. A laser airborne survey was performed to model the land surface elevation. Data concerning the clay-sand contact elevation came from the interpreted stratigraphy based on a series of boreholes and cone penetration tests. This data was combined in a geostatistical model along with the measured piezometric levels in the foundation. This resulted in a contour map showing factors of safety against uplift over the entire downstream area. The use of modern technologies, namely electromagnetic and laser surveys as well as geostatistical tools, was instrumental in defining the limits of an otherwise spread-out problem and to provide an optimal solution, in terms of costs and effectiveness, for the long-term stabilization of the foundation.

关键词: seepage detection     geostatistical analysis     dam monitoring     internal erosion     LIDAR survey    

Advances in polishing of internal structures on parts made by laser-based powder bed fusion

《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0724-0

摘要: The internal structures of metallic products are important in realizing functional applications. Considering the manufacturing of inner structures, laser-based powder bed fusion (L-PBF) is an attractive approach because its layering principle enables the fabrication of parts with customized interior structures. However, the inferior surface quality of L-PBF components hinders its productization progress seriously. In this article, process, basic forms, and applications relevant to L-PBF internal structures are reviewed comprehensively. The causes of poor surface quality and differences in the microstructure and property of the surface features of L-PBF inner structures are presented to provide a perspective of their surface characteristics. Various polishing technologies for L-PBF components with inner structures are presented, whereas their strengths and weaknesses are summarized along with a discussion on the challenges and prospects for improving the interior surface quality of L-PBF parts.

关键词: laser-based powder bed fusion     polishing     internal structures     surface quality     surface features     post process     additive manufacturing    

investigation of the chemical and electrochemical characteristics of planar solid oxide fuel cell with direct internal

Yuzhang WANG, Shilie WENG, Yiwu WENG

《能源前沿(英文)》 2011年 第5卷 第2期   页码 195-206 doi: 10.1007/s11708-011-0148-8

摘要: A fully three-dimensional mathematical model of a planar solid oxide fuel cell (SOFC) with complete direct internal steam reforming was constructed to investigate the chemical and electrochemical characteristics of the porous-electrode-supported (PES)-SOFC developed by the Central Research Institute of Electric Power Industry of Japan. The effective kinetic models developed over the Ni/YSZ anode takes into account the heat transfer and species diffusion limitations in this porous anode. The models were used to simulate the methane steam reforming processes at the co- and counter-flow patterns. The results show that the flow patterns of gas and air have certain effects on cell performance. The cell at the counter-flow has a higher output voltage and output power density at the same operating conditions. At the counter-flow, however, a high hotspot temperature is observed in the anode with a non-fixed position, even when the air inlet flow rate is increased. This is disadvantageous to the cell. Both cell voltage and power density decrease with increased air flow rate.

关键词: planar solid oxide fuel cell (SOFC)     direct internal reforming     chemical reaction     methane     electrochemical    

Can floor-area-ratio incentive promote low impact development in a highly urbanized area?

Ming Cheng, Huapeng Qin, Kangmao He, Hongliang Xu

《环境科学与工程前沿(英文)》 2018年 第12卷 第2期 doi: 10.1007/s11783-017-1002-y

摘要: As an environmental friendly measure for surface runoff reduction, low impact development (LID) has been applied successfully in urban areas. However, due to high price of land and additional expense for LID construction in highly urbanized areas, the developers of real estate would not like to proceed LID exploitation. Floor area ratio (FAR) refers to “the ratio of a building’s total floor area to the size of the piece of land upon which it is built.” Increasing FAR indicates that the developers can construct higher buildings and earn more money. By means of awarding FAR, the developers may be willing to practice LID construction. In this study, a new residential district is selected as a case study to analyze the trade-off between the runoff reduction goal achieving by LID practices and the incentive of awarding FAR to promote LID construction. The System for Urban Stormwater Treatment and Analysis IntegratioN (SUSTAIN) model is applied to simulate the runoff reduction under various LID designs and then derive the Pareto-optimal solutions to achieve urban runoff reduction goals based on cost efficiency. The results indicates that the maximum surface runoff reduction is 20.5%. Under the extremity scenarios, the government has options to award FAR of 0.028, 0.038 and 0.047 and the net benefits developers gain are 0 CNY, one million CNY and two million CNY, respectively. The results provide a LID construction guideline related to awarding FAR, which supports incentive policy making for promoting LID practices in the highly urbanized areas.

关键词: Low impact development     Runoff reduction     Incentive     Floor area ratio     SUSTAIN(System for Urban Stormwater Treatment and Analysis IntegratioN)    

面向物联网的激励感知区块链辅助的智能边缘缓存与计算迁移研究 Article

王倩, 陈思光, 吴蒙

《工程(英文)》 2023年 第31卷 第12期   页码 127-138 doi: 10.1016/j.eng.2022.10.014

摘要:

人工智能的快速发展将物联网推向了一个新阶段,面对数据的爆炸性增长和用户对更高服务质量的迫切需求,边缘计算和缓存被视为富有前景的技术解决手段。然而,边缘节点(Edge Nodes, ENs)中的资源并不是取之不尽的。本文提出了一种面向物联网的激励感知区块链辅助的智能边缘缓存与计算迁移方案,该方案致力于为协作ENs在资源优化和控制方面提供安全和智能的解决方案。具体地,该方案通过联合优化迁移和缓存决策以及计算和通信资源分配,以最大限度地降低EN中完成任务的总成本。此外,为解决上述优化问题,本文设计了区块链激励和贡献联合感知的联邦深度强化学习算法。在本地训练期间,该算法构建了一个激励感知区块链辅助的协作机制,即在安全保障前提下增强ENs参与协作的意愿。同时,提出了一种基于贡献的联邦聚合方法,即基于EN对全局模型性能提升所做贡献来计算其梯度的聚合权重,以提升训练效果。最后,与其它基准方案相比,数值结果证明本文方案具备高效的资源优化效用,同时在降低总成本和缓存性能方面具有显著优势。


 

关键词: 计算迁移     缓存     激励     区块链     联邦深度强化学习    

enhancement and acute biotoxicity removal through the treatment of pharmaceutical wastewater using a combined internal

Liang SUN, Can WANG, Min JI, Fen WANG

《环境科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 481-487 doi: 10.1007/s11783-011-0341-3

摘要: Actual pharmaceutical wastewater was treated using a combined ultrasonic irradiation (US) and iron/coke internal electrolysis (Fe/C) technology. A significant synergetic effect was observed, showing that ultrasonic irradiation dramatically enhanced the chemical oxygen demand (COD) removal efficiencies by internal electrolysis. The effects of primary operating factors on COD removal were evaluated systematically. Higher ultrasonic frequency and lower pH values as well as longer reaction time were favorable to COD removal. The ratio of biochemical oxygen demand (BOD) and COD (B/C) of the wastewater increased from 0.21 to 0.32 after US-Fe/C treatment. An acute biotoxicity assay measuring the inhibition of bioluminescence indicated that the wastewater with overall toxicity of 4.3 mg-Zn ·L was reduced to 0.5 mg-Zn ·L after treatment. Both the raw and the treated wastewater samples were separated and identified. The types of compounds suggested that the increased biodegradability and reduced biotoxicity resulted mainly from the destruction of N,N-2 dimethyl formamide and aromatic compounds in the pharmaceutical wastewater.

关键词: internal electrolysis     ultrasonic     pharmaceutical wastewater     biodegradability     acute biotoxicity    

Influence of temperature on cam-tappet lubrication in an internal combustion engine

CHANG Qiuying, YANG Peiran, WANG Jing, CHEN Quanshi

《机械工程前沿(英文)》 2007年 第2卷 第4期   页码 489-492 doi: 10.1007/s11465-007-0085-8

摘要: The transient thermo-elastohydrodynamic (TEHL) lubrication simulation and isothermal elastohydrodynamic (EHL) simulation were performed on the exhausting cam-tappet friction pair of an internal combustion engine. Although by employing the two models the center pressure, the thickness of the lubricant film and friction coefficient obtained were similar in the changing trend during a rotating cycle, the parameters make a great difference, especially for the thickness of the lubricant film; the TEHL was four times thicker than the EHL. These results show that the temperature should not be neglected in the study of the lubrication of cam-tappet pairs.

关键词: coefficient     combustion     isothermal elastohydrodynamic     temperature     thickness    

Typical off-design analytical performances of internal combustion engine cogeneration

Xiaohong HE, Ruixian CAI

《能源前沿(英文)》 2009年 第3卷 第2期   页码 184-192 doi: 10.1007/s11708-009-0007-z

摘要: Based on experimental data, typical off-design characteristic curves with corresponding formulas of internal combustion engine (ICE) are summarized and investigated. In combination with analytical solution of single-pressure heat recovery steam generator (HRSG) and influence of ambient pressure on combined heat and power (CHP) system, off-design operation regularities of ICE cogeneration are analyzed. The approach temperature difference Δ , relative steam production and superheated steam temperature decrease with the decrease in engine load. The total energy efficiency, equivalent exergy efficiency and economic exergy efficiency first increase and then decrease. Therefore, there exists an optimum value, corresponding to ICE best efficiency operating condition. It is worth emphasizing that Δ is likely to be negative in low load condition with high design steam parameter and low ICE design exhaust gas temperature. Compared with single shaft gas turbine cogeneration, Δ in ICE cogeneration is more likely to be negative. The main reason for this is that the gas turbine has an increased exhaust gas flow with the decrease in load; while ICE is on the contrary. Moreover, ICE power output and efficiency decrease with the decrease in ambient pressure. Hence, approach temperature difference, relative steam production and superheated steam temperature decrease rapidly while the cogeneration efficiencies decrease slightly. It is necessary to consider the influence of ambient conditions, especially the optimization of ICE performances at different places, on cogeneration performances.

关键词: internal combustion engine (ICE)     cogeneration     heat recovery steam generator (HRSG)     off-design     superheated steam     saturated steam     ambient pressure    

Reaction kinetics and internal diffusion of Zhundong char gasification with CO

Yun Liu, Jiangyuan Qu, Xuehui Wu, Kai Zhang, Yuan Zhang

《化学科学与工程前沿(英文)》 2021年 第15卷 第2期   页码 373-383 doi: 10.1007/s11705-020-1949-2

摘要: Mass transfer usually affects the rate of chemical reactions in coal. The effect of internal diffusion on char gasification with CO in the temperature range from 1123 K to 1273 K was investigated via thermo-gravimetric analysis and assessment of char morphology features. The results revealed that the effect of internal diffusion on the initial reaction rate was more significant with an increase of particle size, due to the concentration gradient of the gasification agent within the solid particles. In the early stage of gasification, the generation of new micropores and the opening of closed pores led to an increase in specific surface area. As the reaction proceeded, the openings were gradually expanded and the specific surface area continued to increase. However, with further reaction, disappearance of edge pores, melting and collapse of the pore structure led to a decrease in specific surface area. The intrinsic activation energy and reaction order based on the th-order model were 157.67 kJ∙mol and 0.36, respectively. Thus, temperature zones corresponding to chemical reaction and diffusion control were identified. Moreover, the calculated effectiveness factor provided a quantitative estimation of internal diffusion in the initial stage.

关键词: coal char     CO2 gasification     internal diffusion     pore evolution    

标题 作者 时间 类型 操作

Internal incentives and operations strategies for the water-saving supply chain with cap-and-trade regulation

Zhisong CHEN, Li FANG, Huimin WANG

期刊论文

Cylindrical particulate internal flows: A review

Lizhong HUANG, Xiang GAO, Jianzhong LIN

期刊论文

Current progress on internal medicine in China—2006 Part I

YAO Dingkang, ZHU Liang, ZHAO Xue, MEI Changlin

期刊论文

Unified cycle model of a class of internal combustion engines and their optimum performance characteristics

Shiyan ZHENG

期刊论文

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

Zhi-wen Wang,Jing Tong

期刊论文

Quantitative research of incentive effects of heat-metering policy on energy-saving behavior in Tianjin

Jihong LING,Haitao MA,HuiZhu YU,Jincheng XING

期刊论文

Embankment dam foundation analysis for the decrease of internal erosion likelihood

Marc SMITH

期刊论文

Advances in polishing of internal structures on parts made by laser-based powder bed fusion

期刊论文

investigation of the chemical and electrochemical characteristics of planar solid oxide fuel cell with direct internal

Yuzhang WANG, Shilie WENG, Yiwu WENG

期刊论文

Can floor-area-ratio incentive promote low impact development in a highly urbanized area?

Ming Cheng, Huapeng Qin, Kangmao He, Hongliang Xu

期刊论文

面向物联网的激励感知区块链辅助的智能边缘缓存与计算迁移研究

王倩, 陈思光, 吴蒙

期刊论文

enhancement and acute biotoxicity removal through the treatment of pharmaceutical wastewater using a combined internal

Liang SUN, Can WANG, Min JI, Fen WANG

期刊论文

Influence of temperature on cam-tappet lubrication in an internal combustion engine

CHANG Qiuying, YANG Peiran, WANG Jing, CHEN Quanshi

期刊论文

Typical off-design analytical performances of internal combustion engine cogeneration

Xiaohong HE, Ruixian CAI

期刊论文

Reaction kinetics and internal diffusion of Zhundong char gasification with CO

Yun Liu, Jiangyuan Qu, Xuehui Wu, Kai Zhang, Yuan Zhang

期刊论文