关键词： Marine current turbine   Power generation optimization   System modeling   Fast economic MPC  

摘要： This paper considers the optimal operation of the ocean current turbine power generation system. Based on the model construction of the ocean current turbine system, the model predictive control strategy with economic indicators as the main consideration and the system focusing on real-time control issues are used. It is known that the quadratic form complicates the process to be solved, thereby increasing the solution time. For some complex formulation settings, although the system optimization problem can be solved more effectively, the complexity of the system is increased and the calculation time is increased. Therefore, this paper considers an optimal control that can be obtained fast enough for real-time optimization of the feedback scheme. The economic model predictive control framework is proposed in the paper, with the sensitivity components to solve the formulation, and the paper also consider an iterative optimization algorithm to enhance and improve the response speed of the system without affecting the economics of the system. Finally, all of these concepts are demonstrated on a detailed case study of a marine current turbine generator system. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： River chief system   Water resource   Sustainable management  

摘要： China has established the River Chief System (RCS) to develop mechanisms to achieve success in cross-regional negotiations of the Sustainable Water Resource Management Affairs (SWRMA). This paper aims to investigate the mechanisms developed by RCS and social welfare brought by RCS in China, and thereafter put forward suggestions for the future development of RCS. Therefore, a one-stage cooperation game was used to investigate cross-regional SWRMA negotiations with RCS. The results showed that RCS ensures that cooperative solutions are chosen in cross-regional SWRMA negotiations. Moreover, this paper used a two-stage game to explore cross-regional SWRMA negotiations without involving RCS. In this case, the involvement of the upper-level administrators and the probability of a successful negotiation are endogenously determined by local authorities. The results showed that in cross-regional SWRMA negotiations, both when the upper-level administrators are involved in the first stage and in the second stage, the cooperative solutions would be adopted. Thus, RCS is an inevitable outcome of the cross-regional SWRMA negotiations. In addition, RCS could help to avoid transactional costs and external costs in cross-regional SWRMA negotiations. Based on these results, this study provided the following suggestions: the river chief and local authorities of RCS should be stakeholders;the major members of RCS should be the local authorities influenced mostly by SWRMA quantities;RCS should actively advertise the benefits and the cost-down of SWRMA. (C) 2019 Elsevier B.V. All rights reserved.

关键词： 金氰化浸出过程   动态优化   经济模型预测控制   不确定性   卡尔曼滤波  

摘要： 针对金氰化浸出过程时间常数大、不确定性强等问题,提出了一种基于经济模型预测控制(EMPC)的动态实时优化方法。不同于传统的模型预测控制,EMPC将经济指标直接作为滚动优化的目标函数,在每个采样时刻求解滚动窗口内的最优操作序列。和稳态优化方法相比,基于EMPC的方法能保证动态最优性,提高经济收益。此外,金氰化浸出过程受随机噪声、未知参数可变等不确定性影响,提出使用扩展卡尔曼滤波(EKF),通过构造增广系统对状态变量及不确定参数进行在线同步估计,加强EMPC的准确性和可靠性。仿真结果表明,提出的EMPC+EKF策略能有效提高金氰化浸出过程的经济性能。

关键词： 港口辐射作用   经济模型   连云港   优劣势分析  

摘要： 如果港口能充分地服务它所辐射的内地省份的经济发展,那么港口吞吐量应该与它所辐射省份的经济发展密切相关。为了定量地研究港口与其腹地经济发展的关系,建立以港口吞吐量为被解释变量,辐射的内部省份的GDP为解释变量的经济模型。定量分析连云港吞吐量与其所辐射内地经济发展之间的关系,进一步分析连云港的优劣势,并依此提出促进其经济发展的可行性建议。

关键词： 宏观经济模型   财政措施   经济萎缩   经济产出   主要经济体   居民收入和消费   联合国   对经济影响  

摘要： 联合国经社部的宏观经济模型预测,新冠病毒大流行可导致全球经济今年萎缩近百分之一。另外,如果对经济活动的限制持续到今年第三季度,再加上财政措施无法有效支持居民收入和消费支出,全球经济产出将可能会进一步收缩。新冠病毒大流行对经济影响的严重程度将在很大程度上取决于其对人口流动和主要经济体经济活动的限制期限,以及相应财政措施的规模和效力。

关键词： 农业模型   模型分类   生物模型   环境模型   技术模型   经济模型   应用案例   智慧农业  

摘要： 农业模型、农业人工智能及数据分析等技术贯穿于智慧农业的信息感知、信息传输、信息处理与控制全过程,是智慧农业的核心技术。为进一步明晰农业模型的内涵和作用,促进农业模型进一步研究及应用,推动智慧农业健康、稳定和可持续发展,本研究采用系统分析、比较及关系框图等方法,分析了农业模型的内涵,阐述了农业模型和智慧农业要素与过程的关系,明确了农业模型的作用并附以应用案例,比较了农业模型的国内外重要发展动态与趋势。国内外农业模型研究与应用重要进展比较表明,农业模型研究应用需要考虑农业生物要素的4个水平、农业环境要素的6个尺度、农业技术与农业经济要素的6个层次并采用相应方法进行,农业模型环境要素空间多尺度研究应用有较大发展潜力;农业模型与分子遗传学、感知技术及人工智能技术结合,农业模型研究应用的公私有组织协作,粮食安全挑战将成为农业模型进一步发展的重要推动力,且需更注重将各种农业系统模拟、数据库、和谐性与开放数据及决策支持系统相连接。中国农业模型研究与应用已形成具有中国特色的作物模型系列,也融入农业模型的互比较与改进、智慧农业等世界潮流,需要抢抓机遇,加快发展。农业模型是农业系统要素内及要素间关系的定量化表达,是农业科学定量与综合的重要方法,具有认识论价值,它与感知技术的结合可以在智慧农业数据获取与处理中发挥不可或缺的作用,成为信息农业技术落地应用的重要桥梁和纽带。

关键词： 经济模型   经济学   经济预测与决策   保险业   概率统计  

摘要： 为了保障我国经济的稳步增长,需统计、分析经济数据,并对经济现象进行预测和决策。概率与统计学作为工具学科,在经济学许多领域中应用。本文介绍概率与统计在建立经济模型、经济预测、经济决策、保险业四个方面的常见应用。

关键词： 降本增效   降本模型   物流成本   网络优化   交通经济  

摘要： 以平台型物流企业为研究对象,采用规模经济、密度经济、网络经济等模型进行降本方法研究,分别对样本物流企业的运输与财务总体数据、业务片区运输成本、物流网络均衡优化三个方面进行计算,检验物流企业降本模型适用性。研究发现:1)规模经济模型及其指标通过数据实证对企业宏观降本方向具有指导性;2)密度经济模型与指标以数据计算验证其对物流业务区域运输成本控制具有相当的效果;3)网络经济模型通过提升网络均衡性使物流运输网络的效率与成本经济性提高。研究结果对于平台型物流企业运输降本具有理论意义,为相关企业提供多层次的降本模型,并通过对自身数据的持续挖掘,达到物流企业降本增效的可持续性。

关键词： Circular economy   Moving bed biofilm reactor   Nutrient   Resource recovery   Water reuse  

摘要： Over the last years, an increasing concern has emerged regarding the eco-friendly management of wastewater. Apart from the role of wastewater treatment plants (WWTPs) for wastewater and sewage sludge treatment, the increasing need of the recovery of the resources contained in wastewater, such as nutrients and water, should be highlighted. This would allow for transforming a wastewater treatment plant (WWTP) into a sustainable technological system. The objective of this review is to propose a moving bed biofilm reactor (MBBR) as a novel technology that contributes to the circularity of the wastewater treatment sector according to the principles of circular economy. In this regard, this paper aims to consider the MBBR process as the initial step for water reuse, and nutrient removal and recovery, within the circular economy model.

关键词： Environmental externalities   Microeconomic models   Optimal taxation   Utility  

摘要： The environmental issue has surely become a central theme in the economic debate. From one side, this is analysed through large empirical models, solved numerically, that describe explicitly production and consumption\utility functions. On the other side, when environmental problems have a multinational dimension or, simply, involve a multiplicity of stakeholders, the game theoretical approach, focused on the strategic dimension of this problem, offers analytic solutions based on simple utility functions having only pollution and\or abatement as arguments. Although there are examples of large-scale empirical models taking into account game theoretical insights, the diversity in representing the same problem constitutes a gap for these two economic approaches to find a better integration. The present paper tries to bridge the mentioned gap by offering a family of models enough simple to be solved analytically, but where production and consumption, together with environmental aspects, are explicitly portrayed. Although the paper does not tackle directly the game theoretical aspect, the aim of the proposed family of models is to be used in game theoretical analysis in order to improve their representation of the economic-environmental linkage. Furthermore, in the proposed models, the negative consequences of pollution are divided into their detrimental effect on production activities and on utility. This last aspect is modelled in a novel way through the direct introduction into the utility function of an hypothetical environmental good whose consumption's possibilities are diminished by pollution.