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1.
为了反映系统动力学在经济管理理论与方法中的应用现状,文章重点对2014年以来发表在国内外主流学术期刊上的相关论文进行了系统性综述。分别从系统动力学与经济管理理论与工具、计算方法、综合评价理论和其他仿真模拟方法等结合的情况进行了研究。尝试将系统动力学与经济管理理论与方法进行有效结合,将是研究者们获得突破的重要途径;从理论层面解决系统动力学与经济管理理论与方法的耦合,将是未来研究的一个重点方向;如何实现经济管理理论与方法和系统动力学的内化结合,是未来研究中要深入讨论与尝试的方面。  相似文献   
2.
文章结合数字经济的内涵和外延,分别从数字基础设施、数字产业化、产业数字化等方面构建了数字经济发展水平量化指标体系,基于熵值法测度了中国2010—2018年数字经济发展趋势,并建立灰色预测模型对2019—2028年的数字经济发展走向进行预测。研究结果表明:2010—2018年,中国数字经济发展水平增长了4.4倍,年均增速达到50%,2019—2028年,中国数字经济发展水平增速将不断提高,预计2028年数字经济发展水平将是2018年的5倍。因此,我国要进一步推动新型数字经济基础设施建设,加快传统产业的数字化转型,积极发展电信业等数字产业,以保障我国数字经济快速发展。  相似文献   
3.
经济承压背景下中国能源经济预测与展望   总被引:1,自引:0,他引:1  
2019年中央经济工作会议强调,中国正处在转变发展方式、优化经济结构、转换增长动力的攻关期,经济下行压力不断加大。以此为背景阐述能源经济发展现状,分析重点行业发展前景,通过不同情景下的预测分析,探讨经济承压背景下中国能源经济发展的路径与趋势。根据预测结果,经济承压对各行业的能源消费量存在普遍影响,尤其是煤炭、黑色金属冶炼和汽车行业的能源消费量在未来一段时间将呈下降趋势;在基准情形下,预计到2030年,中国GDP将达到171.97万亿元(2018年不变价水平),能源消费总量约57.09亿吨标准煤,煤炭消费占比将不断下降,清洁能源占比预计达到41.7%。根据预测结果,有针对性地在能源消费结构、能源效率和能源合作方面提出政策建议。  相似文献   
4.
《Risk analysis》2018,38(8):1634-1655
The work in the article presents the development of an application guide based on feedback and comments stemming from various railway actors on their practices of SIL allocation to railway safety‐related functions. The initial generic methodology for SIL allocation has been updated to be applied to railway rolling stock safety‐related functions in order to solve the SIL concept application issues. Various actors dealing with railway SIL allocation problems are the intended target of the methodology; its principles will be summarized in this article with a focus on modifications and precisions made in order to establish a practical guide for railway safety authorities. The methodology is based on the flowchart formalism used in CSM (common safety method) European regulation. It starts with the use of quantitative safety requirements, particularly tolerable hazard rates (THR). THR apportioning rules are applied. On the one hand, the rules are related to classical logical combinations of safety‐related functions preventing hazard occurrence. On the other hand, to take into account technical conditions (last safety weak link, functional dependencies, technological complexity, etc.), specific rules implicitly used in existing practices are defined for readjusting some THR values. SIL allocation process based on apportioned and validated THR values is finally illustrated through the example of “emergency brake” subsystems. Some specific SIL allocation rules are also defined and illustrated.  相似文献   
5.
随着补贴退坡和双积分等重要政策接连出台,中国新能源汽车发展进入新时代。2017年,私人购买量大幅上升到41%,汽车动力电池行业集中度上升,三元电池装机占比显著增加到44%,车桩比有所下降。双积分政策在2017年正式出台,加上国家和地方补贴的进一步退坡,新能源汽车产业加速从政策驱动过渡为市场驱动阶段。但私人消费需求还有待进一步激发,电池等关键零部件的核心技术仍需突破,充电设施的建设与运营面临挑战。双积分和补贴退坡等重要政策实施后,中国汽车行业格局将发生深刻变化。从政策支持与行业发展来看,燃料电池汽车及电动汽车智能化融合发展将是今后重要的发展方向。  相似文献   
6.
The looming oil crisis, pollution, and climate change have pushed governments, corporations, and individuals to think of new policies, new objects/products and new manners to market them – usually under the label of “green economy” (or the shifting towards a sustainable economy).

The changes that are on the way as a result of the envisaged “green revolution” need a broad vision that couples the economy of energetic techniques with the related socio-cultural economy that is induced by, and at the same time reciprocally influences, the mere technical transformations.

Based on previous analysis of theories of socio-technological change and putting at its center the concept of subjectivation in social sciences, this article proposes a theoretical understanding of cultural shifts and their relationship with changes in the practices of production, transfer and use of energy.

First part presents a schema of subjectivation in triangulation, that links the biological level with the material culture and with the representational realm of normativities in our society. It will be developed through the example of electric vehicle as metaphor of the energetic transition. Through this understanding, second part deals with the modeling of the three items as a processual energetic system by using the concepts of surplus and expenditure. Within this frame, we show how disruptions in one of the poles of this model influences the others and bring about changes in the entire Anthropo-Social level. Third part proposes possible types of emerging subjectivities and advances the idea of extending the realm of consciousness to the energetic transfers and their potentiality.  相似文献   

7.
Sequential explanatory mixed method design is the most frequently applied in both health and social sciences literature. It is denoted by ‘QUAN → qual’ which represents the quantitative study occurs first and has greater weight in addressing the study’s aims, and the qualitative study follows to explain quantitative results. Despite the extensive use of sequential explanatory design, there are limited references to this design. Therefore, this methodological paper attempts to fill the gap by providing an illustration in developing a sequential explanatory interview schedule based on complementary-alternative medicine (CAM) study among clinical psychologists in Indonesia. The most important step to develop sequential explanatory interview schedule was the construction of aspects and questions that were immensely grounded on the most notable quantitative results. In this study, eight aspects of interview schedule were constructed after analyses of the nationwide survey. The interview schedule then piloted among participants with fairly similar characteristics to the participants in the main interviews. This process enhanced the quality of questions through feedback from participants and improved the interviewer’s skills through familiarization with questions. It is expected that this reflection report could be adopted as a practical guideline in developing interview schedule for sequential explanatory mixed method design, particularly in the field of psychology.  相似文献   
8.
The exponentially weighted moving average (EWMA) chart is often designed assuming the process parameters are known. In practice, the parameters are rarely known and need to be estimated from Phase I samples. Different Phase I samples are used when practitioners construct their own control chart's limits, which leads to the “Phase I between-practitioners” variability in the in-control average run length (ARL) of control charts. The standard deviation of the ARL (SDARL) is a good alternative to quantify this variability in control charts. Based on the SDARL metric, the performance of the EWMA median chart with estimated parameters is investigated in this paper. Some recommendations are given based on the SDARL metric. The results show that the EWMA median chart requires a much larger amount of Phase I data in order to reduce the variation in the in-control ARL up to a reasonable level. Due to the limitation of the amount of the Phase I data, the suggested EWMA median chart is designed with the bootstrap method which provides a good balance between the in-control and out-of-control ARL values.  相似文献   
9.
Critical infrastructure networks enable social behavior, economic productivity, and the way of life of communities. Disruptions to these cyber–physical–social networks highlight their importance. Recent disruptions caused by natural phenomena, including Hurricanes Harvey and Irma in 2017, have particularly demonstrated the importance of functioning electric power networks. Assessing the economic impact (EI) of electricity outages after a service disruption is a challenging task, particularly when interruption costs vary by the type of electric power use (e.g., residential, commercial, industrial). In contrast with most of the literature, this work proposes an approach to spatially evaluate EIs of disruptions to particular components of the electric power network, thus enabling resilience‐based preparedness planning from economic and community perspectives. Our contribution is a mix‐method approach that combines EI evaluation, component importance analysis, and GIS visualization for decision making. We integrate geographic information systems and an economic evaluation of sporadic electric power outages to provide a tool to assist with prioritizing restoration of power in commercial areas that have the largest impact. By making use of public data describing commercial market value, gross domestic product, and electric area distribution, this article proposes a method to evaluate the EI experienced by commercial districts. A geospatial visualization is presented to observe and compare the areas that are more vulnerable in terms of EI based on the areas covered by each distribution substation. Additionally, a heat map is developed to observe the behavior of disrupted substations to determine the important component exhibiting the highest EI. The proposed resilience analytics approach is applied to analyze outages of substations in the boroughs of New York City.  相似文献   
10.
为了对多个多属性(指标)待评价对象(方案)在多个时间点的发展状态和该时间段内的总体发展水平进行比较分析,根据理想解法和灰关联度法优缺点,提出基于理想解和灰关联度的动态评价方法。该方法基于三维数据,将欧氏距离和灰色关联度相结合,提出一种新贴近度,同时反映了位置关系和数据曲线的相似性差异,兼顾评价指标值差异程度和增长程度。最后将该方法应用于"十二五"期间省域循环经济生态效益评价,通过实例验证该方法实际应用上的有效性。  相似文献   
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