关键词： 产业转移   水污染   脱钩分析   地理集中度   不一致指数   不均衡指数   空间计量经济模型  

摘要： 豫湘赣皖四省是新一轮产业转移的重要承接地.采用地理集中度、不一致指数、不均衡指数、脱钩分析及空间计量经济模型等方法对2010-2015年豫湘赣皖承接产业转移与水污染关系的时空演变趋势进行了分析.结果表明:1)产业转移地理集中度由聚集向分散演变,呈现出北高南低的格局;2)水污染地理集中度高值、较高值的城市主要集中在四省的中北部,但分布较为分散;3)豫湘赣皖地区承接产业转移与水污染的空间格局有趋向均衡的趋势,但不均衡性仍较明显;4)豫湘赣皖承接产业转移与水污染大多处于脱钩状态,脱钩状态城市、负脱钩状态城市和连接状态城市的比值分别为90.9%、5.46%、3.64%;5)空间关联效应是水污染的重要因素,回归系数为0.35;6)产业转移和工业总产值对水污染具有正向作用,污染治理对水污染具有负向作用.

关键词： 海绵城市   低影响开发   全生命周期   综合效益   经济模型  

摘要： 论文从经济效益、环境效益以及社会效益3个层面出发,分析海绵城市背景下低影响开发(LID)措施效益的构成要素。经济层面包括减少能源消耗、雨水资源回收利用、减少传统雨水管网运行费用;环境层面包括净化空气、减少碳排放、补充地下水;社会层面包括减少消除污染的社会投入、减少洪泛成本等。同时运用环境经济学等方法,研究LID措施各项效益的货币化方法。然后结合全生命周期理论,从成本与效益的角度出发,构建LID措施净收益效益指标。以镇江市海绵城市建设为实际案例,量化研究了海绵城市背景下LID措施的综合效益。研究结果表明,建设海绵城市项目在节水、节能、减排、截污、防洪等方面为镇江市带来了较大的经济受益,每单位面积的LID措施能获得的年净效益为6.53元/m^2,值得推广。针对研究结果,论文提出了完善激励补偿政策、完善海绵城市技术体系、加强雨水资源化产业、因地制宜选择LID措施等建议。

关键词： cognitive behavioral therapy   cost-effectiveness   decision-analytic model   depression  

摘要： Objectives: Cognitive behavioral therapy (CBT) is an effective treatment for depression. Different CBT delivery formats (faceto-face [F2F], multimedia, and hybrid) and intensities have been used to expand access to the treatment. The aim of this study is to estimate the long-term cost-effectiveness of different CBT delivery modes. Methods: A decision-analytic model was developed to evaluate the cost-effectiveness of different CBT delivery modes and variations in intensity in comparison with treatment as usual (TAU). The model covered an average treatment period of 4 months with a 5-year follow-up period. The model was populated using a systematic review of randomized controlled trials and various sources from the literature. Results: Incremental cost-effectiveness ratios of treatments compared with the next best option after excluding all the dominated and extended dominated options are: 209/quality-adjusted life year (QALY) for 6 (sessions) x 30 (minutes) F2F-CBT versus TAU;4 pound 453/QALY for 8 x 30 F2F versus 6 x 30 F2F;12 pound 216/QALY for 8 x 60 F2F versus 8 x 30 F2F;and 43 pound 072/QALY for 16 x 60 F2F versus 8 x 60 F2F. The treatment with the highest net monetary benefit for thresholds of 20 pound 000 to 30 pound 000/QALY was 8 x 30 F2F-CBT. Probabilistic sensitivity analysis illustrated 6 x 30 F2F-CBT had the highest probability (32.8%) of being cost-effective at 20 pound 000/QALY;16 x 60 F2F-CBT had the highest probability (31.0%) at 30 pound 000/QALY. Conclusions: All CBT delivery modes on top of TAU were found to be more cost-effective than TAU alone. Four F2F-CBT options (6 x 30, 8 x 30, 8 x 60,16 x 60) are on the cost-effectiveness frontier. F2F-CBT with intensities of 6 x 30 and 16 x 60 had the highest probabilities of being cost-effective. The results, however, should be interpreted with caution owing to the high level of uncertainty.

关键词： Scheduling   Optimization   Distributed computing   Cloud computing   Service computing   Consolidation of servers  

摘要： This paper presents a new opportunistic scheduling and resource consolidation system based on an economic model related to different service level agreements (SLAs) classes. The goal is to address the problem of companies that manage a private infrastructure of machines, i.e., a cloud platform and would like to optimize the scheduling of several requests submitted online by users. For the sake of simplicity of the presentation, the proposed economic model has two SLAs classes (qualitative and quantitative) with three Quality of Service for each SLA class (Premium, Advanced and Best effort). The consequence of this choice as well as the need to serve requests as they come have an impact on the algorithmic ways to consolidate an infrastructure. Indeed, our system proposes a new allocation heuristic that adapts the number of active machines in the cloud according to the global resources usage of all machines inside the infrastructure. This heuristic can be examined as a consolidation heuristic, based on the idea that the system can make reasonable choices, based on the SLAs, for the placement and the allocation of resources for each request. Experimentation with our system is conducted on Prezi (Web workload) and Google Cloud Data (HPC-oriented workload) traces, and they demonstrate the potential of our approach under different scenarios. From a methodological point of view, we propose a general framework which is limited in scope, for the sake of simplicity in reading the paper, with a small number of SLAs, but the idea can be extended to many more SLAs and performance metrics. In this way, the user or the provider operating the cloud have more latitude, thanks to our multi-criteria approach, to control the workload without a sacrifice on performance.

关键词： Hydro-economic models   Positive mathematical programming   Data assimilation   Decision support systems  

摘要： The management of water resources among competing uses presents a complex technical and policy challenge. Integrated hydro-economic models capable of simulating the hydrologic system in irrigated and non-irrigated regions including the response of farmers to hydrologic constraints and economic and policy incentives, provide a framework to understand biophysical and socioeconomic implications of changing water availability. We present a transformative hydro-economic model of agricultural production driven by multi-sensor satellite observations, outputs from regional climate models, and socioeconomic data. Our approach overcomes the limitations of current decision support systems for agricultural water management and provides policymakers and natural resource managers with satellite data-driven, state-wide, operational models capable of anticipating how farmers allocate water, land, and other resources when confronted with new climate patterns, policy rules, or market signals. The model can also quantify how farming decisions affect agricultural water supplies. We demonstrate the model through an application in the state of Montana.

关键词： economic MPC   practical stability   relaxed stability   robust stability   smart building   tube-based robust MPC  

摘要： This article deals with an improved scheme of tube-based robust economic model predictive control (TEMPC). The controller is robust to unknown but bounded disturbances where guarantees recursive feasibility, robust stability, and convergence to the economically optimal operating point. Time-varying economic criteria are considered in the stage cost function of the control design. Initial states of the nominal-nondisturbed-system are considered as decision variables. It lets the controller know more information about the real-disturbance affected-system to take advantage of the recursive horizon approach. It also increases the control degree of freedom and enlarges the region of attraction. Making the closed-loop system work at the economically optimal operating point contradicts with the economic behavior. A convex optimization problem is represented to keep the economic performance from degradation as much as possible. It modifies the control optimization problem to economic optimally guarantee the closed-loop robust stability, which is called practical stability. It is shown that more economic behavior could be achieved under some conditions by relaxing the stability but maintaining the recursive feasibility guarantee, which is called relaxed stability. To show the efficiency of the proposed method, it is applied to the building energy management of smart grid. A commercial microgrid with battery energy storage dynamics and refrigeration dynamics of a supermarket are considered as a smart building system where the time-varying electricity price of the main grid is considered in the objective function. The results show valuable achievements in the TEMPC economic performance.

关键词： Microgrid   Renewable energy resources   Optimization   Hybrid economic model predictive control   Energy management system   Weather data  

摘要： Microgrid management is a multi-objective problem that involves purchasing and selling energy, time-variant renewable generation, and maintenance costs. The microgrid can operate autonomously on an island or through mode connected with the main grid. This paper proposes an original optimization model for the management of an isolated microgrid that allows the automatic grid connection to provide ancillary services to the main grid, such as selling the excess renewable generation and purchasing electricity to charge the battery bank. The proposed optimization is formulated via hybrid economic model predictive control using weather forecasts performed by a mesoscale meteorological model. It includes new constraints to meet a specific connection/disconnection regulation, such as the minimum connection/disconnection time and the maximum connection frequency. This paper also proposes a new hybrid model of a battery bank that includes the grid connection/disconnection. Furthermore, the hybrid models of renewable energy sources convert weather data to the wind and photovoltaic power by using the mixed logical dynamical framework. The proposed algorithm is sensitive to the forecasting error, which causes variations of 1% in the met demand, 27.3% in the battery bank costs, and 13.3% in the financial profits. Compared to multi-period mixed integer linear programming and rule-based strategy, we show that the proposed controller manages the microgrid more safely (i.e., it provides state of charge below its critical value during a period less than 25% of that offered by other strategies). In locations with high energy generation, only the proposed optimization furnishes energy sale profit.

关键词： 线性经济模型   换基迭代   退化   循环  

摘要： 文章针对线性规划技术—Dantzig方法的换基迭代准则进行了研究,作了计算方法上的改进,提高了算法的可靠性和有效性,并给出两个具体应用范例。研究结果表明:改进后的迭代方法可减少换基迭代次数,实现增量最优的步长迭代,同时对退化情形的线性经济模型可规避换基迭代循环现象的发生。

关键词： 共享单车   经济模型   增量市场   准备就绪   讲效率   存量市场   互联网   天时地利人和  

摘要： “它生来具有讲述宏大故事的可能性,既能讲规模故事,也能讲效率故事,还能讲环保故事,同时这个行业的单体经济模型都相对容易计算,一切都已经准备就绪。”共享单车正好具备所有条件。这是一场无声的战争,整个互联网线上流量红利几乎枯竭,共享单车成了低成本获客的关键。当一众人都往存量市场挤,共享单车出现在了增量市场,它成功找准了点,但也有人觉得它太过浮躁,天时地利人和一样都没有踩准。