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1.
The circular economy (CE) requires companies to rethink their supply chains and business models. Several frameworks found in the academic and practitioner literature propose circular economy business models (CEBMs) to redefine how companies create value while adhering to CE principles. A review of these frameworks shows that some models are frequently discussed, some are framework specific, and some use a different wording to refer to similar CEBMs, pointing to the need to consolidate the current state of the art. We conduct a morphological analysis of 26 current CEBMs from the literature, which includes defining their major business model dimensions and identifying the specific characteristics of these dimensions. Based on this analysis, we identify a broad range of business model design options and propose six major CEBM patterns with the potential to support the closing of resource flows: repair and maintenance; reuse and redistribution; refurbishment and remanufacturing; recycling; cascading and repurposing; and organic feedstock business model patterns. We also discuss different design strategies to support the development of these CEBMs.  相似文献   

2.
从我国工业开发区的现状出发,论述了工业开发区实施环境—经济双向控制的必要性,规划的思路,规划目标体系的建立,规划的编制程序,多目标规划模型的建立,对工业开发区的环境规划提供了一个新方法.  相似文献   

3.
The rapid technological evolution and adoption of consumer electronics highlights a growing need for adaptive methodologies to evaluate material consumption at the intersection of technological change and increasing consumption. While dematerialization and the circular economy (CE) have both been proposed to mitigate increasing material consumption, recent research has shown that these methods may be ineffective at achieving net material use reduction: When focused on specific products, these methods neglect the effects of complex interactions among and increasing consumption of consumer electronic products. The research presented here develops and applies a material flow analysis aimed at evaluating an entire “product ecosystem,” thereby including the effects of increasing consumption, product trade‐offs, and technological innovations. Results are then used to evaluate the potential efficacy of “natural” dematerialization (occurring as technology advances or smaller products substitute for larger ones) and CE (closing the loop between secondary material supply and primary material demand). Results show that material consumption by the ecosystem of electronics commonly used by U.S. households peaked in 2000. This consumption relies on increasingly diverse materials, including gold, cobalt, and indium, for whom secondary supply is still negligible, particularly given low recovery rates, often less than 1%. Potential circularity metrics of material “dilution,” “dispersion,” and “demand mismatch” are also evaluated, and indicate that CE approaches aimed at closing the loop on consumer electronic material still face several critical barriers particularly related to design and efficient recycling infrastructure.  相似文献   

4.
Risk assessment is an essential prelude to the development of accident prevention strategies in any chemical or petrochemical industry. Many techniques and methodologies such as HAZOP, failure mode effect analysis, fault tree analysis, preliminary hazard analysis, quantitative risk assessment and probabilistic safety analysis are available to conduct qualitative, quantitative, and probabilistic risk assessment. However, these methodologies are limited by: extensive data requirements, the length of study, results are not directly interpretable for decision making, simulation is often difficult, and they are applicable only at the operation or late design stage. Khan et al. (2001a) recently proposed a detailed methodology for risk assessment and safety evaluation. This methodology is simple, yet it is effective in safety and design-related decision making, and it has been applied successfully to many case studies. It is named SCAP, where S stands for safety, C and A stand for credible accident respectively, and P stands for probabilistic fault tree analysis. This paper recapitulates the SCAP methodology and demonstrates its application to a petrochemical plant.  相似文献   

5.
干旱地区经济-生态环境系统规划方法与应用   总被引:9,自引:1,他引:9  
张振兴  郭怀成  陈冰  张宁 《生态学报》2002,22(7):1018-1027
从干旱地区经济-生态环境系统的动态性,综合性,多目标性和不确定性等特征出发,提出用不确定性多目标规划(IMOP)模型来解决干旱地区以水资源为核心的生态环境规划优化问题,建立了干旱地区经济与生态环境系统不确定性多目标规划模型(IMOPMEES),应用模型算法退化形式进行多目标规划的求解,并以新疆和墨洛地区为具体研究对象,采用IMOPMEES进行可持续发展规划,应用交互式调整和情景分析的方法得到模型在两种情景下的优化方案,进而对两种情景进行综合分析比较,为决策者提供科学合理的决策依据,研究表明IMOP模型可以充分反映干旱地区经济-生态环境系统的不确定性和动态性,并有效地协调目标之间的冲突,为干旱地区经济-生态环境规划工作提供了一种较为有力的工具。  相似文献   

6.
Under the network environment, the trading volume and asset price of a financial commodity or instrument are affected by various complicated factors. Machine learning and sentiment analysis provide powerful tools to collect a great deal of data from the website and retrieve useful information for effectively forecasting financial risk of associated companies. This article studies trading volume and asset price risk when sentimental financial information data are available using both sentiment analysis and popular machine learning approaches: artificial neural network (ANN) and support vector machine (SVM). Nonlinear GARCH-based mining models are developed by integrating GARCH (generalized autoregressive conditional heteroskedasticity) theory and ANN and SVM. Empirical studies in the U.S. stock market show that the proposed approach achieves favorable forecast performances. GARCH-based SVM outperforms GARCH-based ANN for volatility forecast, whereas GARCH-based ANN achieves a better forecast result for the volatility trend. Results also indicate a strong correlation between information sentiment and both trading volume and asset price volatility.  相似文献   

7.
8.
The food industry in Australia (agriculture and manufacturing) plays a fundamental role in contributing to socioeconomic sectors nationally. However, alongside the benefits, the industry also produces environmental burdens associated with the production of food. Sectorally, agriculture is the largest consumer of water. Additionally, land degradation, greenhouse gas emissions, energy consumption, and waste generation are considered the main environmental impacts caused by the industry. The research project aims to evaluate the eco‐efficiency performance of various subsectors in the Australian agri‐food systems through the use of input‐output–oriented approaches of data envelopment analysis and material flow analysis. This helps in establishing environmental and economic indicators for the industry. The results have shown inefficiencies during the life cycle of food production in Australia. Following the principles of industrial ecology, the study recommends the implementation of sustainable processes to increase efficiency, diminish undesirable outputs, and decrease the use of nonrenewable inputs within the production cycle. Broadly, the research outcomes are useful to inform decision makers about the advantages of moving from a traditional linear system to a circular production system, where a sustainable and efficient circular economy could be created in the Australian food industry.  相似文献   

9.
京医通业务系统启动后,推行了线上挂号缴费业务,在一定程度上提高医院工作效率,提升患者就医体验,改善患者就医环境。但同时也带来了一些内部控制特别是资金安全管理的风险,针对这些风险,采取了相应的控制措施,加强内部控制管理和风险防范。  相似文献   

10.
Renewable energy (RE) technologies are looked upon favorably to provide for future energy demands and reduce greenhouse gas (GHG) emissions. However, the installation of these technologies requires large quantities of finite material resources. We apply life cycle assessment to 100 years of electricity generation from three stand‐alone RE technologies—solar photovoltaics, run‐of‐river hydro, and wind—to evaluate environmental burden profiles against baseline electricity generation from fossil fuels. We then devised scenarios to incorporate circular economy (CE) improvements targeting hotspots in systems’ life cycle, specifically (1) improved recycling rates for raw materials and (ii) the application of eco‐design. Hydro presented the lowest environmental burdens per kilowatt‐hour of electricity generation compared with other RE technologies, owing to its higher efficiency and longer life spans for main components. Distinct results were observed in the environmental performance of each system based on the consideration of improved recycling rates and eco‐design. CE measures produced similar modest savings in already low GHG emissions burdens for each technology, while eco‐design specifically had the potential to provide significant savings in abiotic resource depletion. Further research to explore the full potential of CE measures for RE technologies will curtail the resource intensity of RE technologies required to mitigate climate change.  相似文献   

11.
In recent years, risk management has attracted a great deal of attention from both researchers and practitioners. Complexity and uncertainty in many practical problems require new methods and tools. Risk management can be used as a tool for greater rewards, not just control against loss. Enterprise risk management has become an important topic in today's more complex, inter-related global business environment, replete with threats from natural, political, economic, and technical sources. Risks are studied from different silo disciplinary perspectives, with a discussion of how various methods and tools are used to optimize risk management.  相似文献   

12.
Due to resource scarcity and environmental degradation, a new development concept emphasizing environmental concerns, called the circular economy (CE), has been enacted in legislation in China. This environmental management concept can be implemented at three levels, namely, region, industrial zone, and individual enterprise, with the objective of boosting economic development while lessening environmental and resource challenges. Environmental supply chain cooperation (ESCC), an approach that utilizes customer and supplier cooperation in environmental management, has been initiated among Chinese enterprises. Using survey data collected from 396 Chinese manufacturers, we examine the role of ESCC practices in influencing the relationship between implementing CE practices and the achievement of performance outcomes by testing the moderation and mediation effects of ESCC practices on the CE practice‐performance relationship through hierarchical regression analysis. Our data analyses indicate that ESCC practices are useful by moderation and, in some cases, essential by mediation, for Chinese manufacturers seeking to realize the performance targets desired in CE practices. The results highlight the need for Chinese manufacturers to improve supply chain coordination in their implementation of CE. On the policy side, our research findings suggest that ESCC practices are beneficial and, in some cases, necessary for the development of CE in China.  相似文献   

13.
A guideline is presented for selection of sensitivity analysis methods applied to microbial food safety process risk (MFSPR) models. The guideline provides useful boundaries and principles for selecting sensitivity analysis methods for MSFPR models. Although the guideline is predicated on a specific branch of risk assessment models related to food-borne diseases, the principles and recommendations provided are typically generally applicable to other types of risk models. Applicable situations include: prioritizing potential critical control points; identifying key sources of variability and uncertainty; and refinement, verification, and validation of a model. Based on the objective of the analysis, characteristics of the model under study, amount of detail expected from sensitivity analysis, and characteristics of the sensitivity analysis method, recommendations for selection of sensitivity analysis methods are provided. A decision framework for method selection is introduced. The decision framework can substantially facilitate the process of selecting a sensitivity analysis method.  相似文献   

14.
With the rapid growth of highway mileage and vehicles, the Chinese highway traffic system (HTS) has become one of the great resource consumers. This article attempts to evaluate the material metabolism of China's HTS during 2001–2005 using the approach of material flow analysis (MFA) and to explore possible measures to promote circular economy throughout HTS. We measured a set of indicators to illustrate the whole material metabolism of China's HTS. The results indicated that the direct material input (DMI) of China's HTS increased from 1181.26 million tonnes (Mt) in 2001 to 1,874.57 Mt in 2005, and about 80% of DMI was accumulated in the system as infrastructure and vehicles. The domestic processed output (DPO) increased by 59.0% from 2001 to 2005. Carbon dioxide and solid waste accounted for 80.5% and 10.4% of DPO, respectively. The increase of resource consumption and pollutant emissions kept pace with the growth of transportation turnover. All these suggest that China's HTS still followed an extensive linear developing pattern with large resource consumption and heavy pollution emissions during the study period, which brought great challenges to the resources and the environment. Therefore, it's high time for China to implement a circular economy throughout the HTS by instituting resource and energy savings, by reducing emissions in the field of infrastructure construction and maintenance, by reducing vehicles’ energy and materials consumption, and by recycling waste materials.  相似文献   

15.
Ecological risk actually refers to two separate things. First, risk to the environment as a result of human activity. Contaminated sites are an example. Second, risk to the biota—flora, fauna, and people—as a result of environmental hazards. Geophysical risk arising from natural hazards is an example. Risk is a combination of likelihoods and consequences. This article examines methods used to quantify the consequences. At the general level, such methods are linked to the methods used to quantify the likelihoods and thus to quantify the risks. It is possible to use the existing frameworks of risk management, health risk assessment, and ecological risk analysis to develop a risk management framework that is suitable for ecological risk assessment. The framework consists of the following steps:
  1. Determine concernsby using risk assessment techniques for various scenarios.

  2. Identify the consequences by systematically identifying hazards.

  3. Undertake calculations by using relevant models.

  4. Evaluate certainties, uncertainties, and probabilities involved in the calculations of the vulnerability and of the exposure.

  5. Compare with criteriato assess the need for further action.

  6. Determine and act on options to control, mitigate, and adapt to the risk.

  7. Communicatethe results to those who need to know.

  相似文献   

16.
Flood control engineering system risk assessment entails fuzziness. An assessment model is developed, based on the improved fuzzy comprehensive assessment method that developed a new index (Sfin ) to judge the assessment class. The model is used to assess the flood control engineering risk of a case in China. The results show that the proposed model in the present article can rationally determine the risk status of a flood control engineering system, and has higher resolution compared to the two conventional methods, fuzzy comprehensive assessment and matter-element model method. The proposed model is flexible and adaptable for determining flood control engineering system risk status.  相似文献   

17.
栓皮栎种群数量动态的谱分析与稳定性   总被引:20,自引:0,他引:20  
1 前 言波动可出现于所有的植被中 ,而谱分析的方法可以揭示种群数量变动的周期性波动。Veblen等通过老龄林结构和动态分析认为 :优势种的更替是周期循环的 ,而不是一个连续发展过程[2 ]。谱分析方法在昆虫数量动态研究中应用较多[1 ],在植物生态学研究中也有数例应用 ,伍业钢等[2 ]首次将之应用于阔叶红松林的演替与天然更新过程的研究 ,认为红松天然更新过程的周期波浪式发展 ,是其稳定的一个特点。但对于林木年龄较小、增长特征较明显的种群 ,谱分析方法是否适用 ,其结果与种群稳定性的关系如何 ,则尚未见报道。本文以河南省分布…  相似文献   

18.
Dynamic material flow analysis (MFA) provides information about material usage over time and consequent changes in material stocks and flows. In order to understand the effect of limited data quality and model assumptions on MFA results, the use of sensitivity analysis methods in dynamic MFA studies has been on the increase. So far, sensitivity analysis in dynamic MFA has been conducted by means of a one‐at‐a‐time method, which tests parameter perturbations individually and observes the outcomes on output. In contrast to that, variance‐based global sensitivity analysis decomposes the variance of the model output into fractions caused by the uncertainty or variability of input parameters. The present study investigates interaction and time‐delay effects of uncertain parameters on the output of an archetypal input‐driven dynamic material flow model using variance‐based global sensitivity analysis. The results show that determining the main (first‐order) effects of parameter variations is often sufficient in dynamic MFA because substantial effects attributed to the simultaneous variation of several parameters (higher‐order effects) do not appear for classical setups of dynamic material flow models. For models with time‐varying parameters, time‐delay effects of parameter variation on model outputs need to be considered, potentially boosting the computational cost of global sensitivity analysis. Finally, the implications of exploring the sensitivities of model outputs with respect to parameter variations in the archetypical model are used to derive model‐ and goal‐specific recommendations on choosing appropriate sensitivity analysis methods in dynamic MFA.  相似文献   

19.
Researches on hydrologic extreme events have great significance in reducing and avoiding the severe losses and impacts caused by natural disasters. When forecasting hydrologic design values of the hydrologic extreme events of interest by the conventional hydrologic frequency analysis (HFA) model, the results cannot take uncertainties and risks into account. In this article, in order to overcome conventional HFA model's disadvantages and to improve hydrologic design values’ forecast results, an improved HFA model named AM-MCMC-HFA is proposed by employing the AM-MCMC algorithm (adaptive Metropolis-Markov chain Monte Carlo) to HFA process. Differing with conventional HFA model, which is seeking single optimal forecast result, the AM-MCMC-HFA model can not only get the optimal but also the probabilistic forecast results of hydrologic design values. By applying to two obviously different hydrologic series, the performances of the model proposed have been verified. Analysis results show that four factors have great influence on hydrologic design values’ reliability, and also indicate that AM-MCMC-HFA has the ability of assessing the uncertainties of parameters and hydrologic design values. Therefore, by using the AM-MCMC-HFA model, hydrologic designs tasks can be operated more reasonably, and more rational decisions can be made by governmental decision-makers and public in practice.  相似文献   

20.
通过野外定点观察,运用花粉—胚珠比、联苯胺—过氧化氢法、杂交指数、人工授粉和套袋试验等方法,对黄花角蒿(Incarvillea sinensis var. przewalskii)的开花动态及繁育系统进行了研究。结果表明:黄花角蒿种群花期一般为6~9月,单花花期一般为2~3 d,花雌雄异熟,雄蕊先熟,雌雄蕊异位。单花花期依其形态和散粉特征可分为散粉初期、散粉盛期、散粉末期、凋谢期4个时期。黄花角蒿花粉—胚珠比为331.3,杂交指数等于5,结合人工授粉和套袋实验结果可以确定该物种的繁育系统为异交,部分自交亲和,需要传粉者。套袋实验及实地观察显示黄花角蒿为虫媒传粉。  相似文献   

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