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A FRAMEWORK FOR PROCESS INDICATORS TO MONITOR
FOR SUSTAINABLE DEVELOPMENT: PRACTICE TO AN URBAN WATER SYSTEM 总被引:2,自引:0,他引:2
Although very often used, the concept of sustainable development has not yet been perceived pragmatically. Due to its process
nature, in this paper, we argue that sustainable development is a process in which the essential feedback loops, or Viability Loops as we name them, in the system in question are kept healthy and functional. This process deals with evolutionary changes
with the end point not known in advance. According to this perception, measurement of sustainable development does not make
sense. Rather, we should look for the process indicators to monitor systems for sustainable development. The purpose of the
paper is to develop a methodology to deal with monitoring systems for sustainable development and its practice in an urban
water system. Using a system dynamics approach, the paper adopts a systemic monitoring framework based on the idea of Viability Loops to define process indicators to monitor systems for sustainable development. To illustrate the application of the framework,
its practice in the urban water system of Tehran, the capital of Iran, is provided as an example. The example of the urban
water supply system of Tehran is given as a case study, albeit with some unavailable data. Here, four typical viability loops
are discussed. The results of this application show that the flows of informative signals are lacking. Adopting the process
indicators, we can see the gaps between the public perceptions of water abundance, the costs of water provision and energy
utilizations, and what is going on in the reality are getting wider. That indicates that the viability loops are not functional
enough to produce effective changes to offset the reinforcing mechanisms. The sustainable development of the system is impaired
due to the persistence of those reinforcing mechanisms. 相似文献
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Dynamic simulation of urban water metabolism under water environmental carrying capacity restrictions 总被引:2,自引:0,他引:2
A revised concept for urban water metabolism (UWM) is presented in this study to address the inadequacies in current research on UWM and the problems associated with the traditional urban water metabolic process. Feedback loops can be analyzed to increase the water environmental carrying capacity (WECC) of the new urban water metabolism system (UWMS) over that of a traditional UWMS. An analysis of the feedback loops of an UWMS was used to construct a system dynamics (SD) model for the system under a WECC restriction. Water metabolic processes were simulated for different scenarios using the Tongzhou District in Beijing as an example. The results for the newly developed UWM case showed that a water environment of Tongzhou District could support a population of 1.1926 × 106, an irrigation area of 375.521 km2, a livestock of 0.7732 × 106, and an industrial value added of ¥193.14 × 109 (i.e. about US$28.285× 109) in 2020. A sensitivity analysis showed that the WECC could be improved to some extent by constructing new sewage treatment facilities or by expanding the current sewage treatment facilities, using reclaimed water and improving the water circulation system. 相似文献
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目的介绍计算机仿真技术的特点及其在动态设备系统设计中的应用。方法首先简要介绍仿真技术的发展和特点,其次介绍一些仿真经验,最后通过若干实例介绍Simulink软件在动态设备系统中的应用。结果基于Simulink仿真,可以快速获得系统运行过程中的各种所关注的参数运行结果,为系统性能评估和优化提供可靠的依据。结论计算机仿真技术已经日趋成熟,应用于动态环境试验系统设计中,可提升设计水平。 相似文献
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Hydrogen (H2) explosion effects recently examined, are confirming the devastating loss scenarios to humans, environment, assets, and associated business interruption. H2 production is a core process in refineries used in further process steps. Steam reforming of natural gas or a mix with naphtha or LPG is a common hydrogen production technique, where the latest technologies have adopted enhanced metallurgies to minimize explosion risk and the associated maintenance cost following plant degradation owing to corrosion effects. However, corrosion rates are still high in specific areas of piping and process equipment. The aim of this paper is to present a methodology based on semi-quantitative RBI modeling according to regulations by API and recent EN standards, adopting a family of linear regression forecasting models that depict the yearly corrosion rate (per corrosion loop) of a hydrogen production steam reforming unit; this is done under different operating conditions (e.g., temperature, pressure, and fluid speed), metallurgy and other related physicochemical variables. The model is based on the examination of both ultrasonic wall thinning measurements and the examination of quantitative crosslinking total corrosion effects along with the physicochemical properties prevailing in different plant corrosion loops. The outcome of the regression analysis is an expansive family of multivariable equations describing, with a defined accuracy, the yearly corrosion rate and associated lifespan forecast per corrosion loop, and per examined part. These equations were further utilized in a custom-made database that can be used as an additional loss prevention tool by the hydrogen production unit management team. Evaluation results regarding the tool efficiency are presented in the following of this paper. 相似文献
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Tore Sderqvist Hanna Nathaniel Daniel Franzn Frida Franzn Linus Hasselstrm Fredrik Grndahl Rajib Sinha Johanna Stadmark sa Strand Ida Ingmansson Sofia Lingegrd Jean-Baptiste Thomas 《Ambio》2022,51(5):1302
Harvesting beach-cast can help mitigate marine eutrophication by closing land-marine nutrient loops and provide a blue biomass raw material for the bioeconomy. Cost–benefit analysis was applied to harvest activities during 2009–2018 on the island of Gotland in the Baltic Sea, highlighting benefits such as nutrient removal from the marine system and improved recreational opportunities as well as costs of using inputs necessary for harvest. The results indicate that the activities entailed a net gain to society, lending substance to continued funding for harvests on Gotland and assessments of upscaling of harvest activities to other areas in Sweden and elsewhere. The lessons learnt from the considerable harvest experience on Gotland should be utilized for developing concrete guidelines for carrying out sustainable harvest practice, paying due attention to local conditions but also to what can be generalized to a wider national and international context.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01641-8. 相似文献
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Susan J. Colarullo Manoutchehr Heidari Thomas Maddock III 《Journal of the American Water Resources Association》1984,20(5):747-760
A groundwater hydraulic management model is used to identify the optimal strategy for allocating limited fresh-water supplies and containing wastes in a hypothetical aquifer affected by brine contamination from surface disposal ponds. The present cost of pumping from a network of potential supply and interception wells is minimized over a five-year planning period, subject to a set of hydraulic, institutional, and legal constraints. Hydraulic constraints are formulated using linear systems theory to describe drawdown and velocity variables as linear functions of supply and interception well discharge decision variables. Successful validation of the optimal management strategy suggests that the model formulation can feasibly be applied to define management options for locally contaminated aquifer systems which are used to fulfill fresh-water demands. 相似文献