Whether industrial agglomeration (IA) can effectively improve green development efficiency (GDE) is crucial for both the smooth realization of China's dual carbon goals and the country's future green development. This paper evaluated the GDE and the IA of 283 cities in China by constructing an improved data envelopment analysis model and a location entropy model. The nonlinear effect of IA on GDE was investigated empirically using the recently created spatial statistical model and mediating effect model. The results showed that (1) China's overall GDE shows a good upward trend, while IA shows a slight downward trend. The differences between cities are very obvious. High-GDE cities are concentrated in coastal areas, and their average annual growth rate (AAGR) is low or even negative. Low-GDE cities are concentrated mainly in inland areas, with high AAGR. (2) There is a strong nonlinear U-shaped correlation between IA and GDE. (3) Influence factors such as economic development level (GDP) will promote GDE improvement, while influence factors such as energy structure will inhibit GDE improvement. (4) Industrial structure upgrading plays a major intermediary role between IA and GDE. Therefore, this paper proposes corresponding policy implications for how IA can promote green development.

Global warming caused by excessive emissions of carbon dioxide (CO2) has become a hot topic globally in today’s society, and optimizing carbon emission performance (CEP) is an effective way to alleviate CO2 emissions. Many studies have explored CEP at the global, national, provincial and sector levels. However, due to the difficulty in obtaining energy consumption data, there is a lack of studies at the urban agglomeration and city levels. Taking the urban agglomeration dimension as the starting point, this paper constructs an improved epsilon-based measure (EBM) model to measure the CEP of the Yellow River Basin. A spatial data analysis model was introduced to explore the regional spatial characteristics of CEP. The newly developed spatial statistical model was used to study the driving factors of CEP. The results showed that: (1) The overall CEP of the Yellow River Basin was relatively high, showing an upward trend of volatility. There were significant differences between the seven urban agglomerations and 69 cities. (2) The CEP of the Yellow River Basin showed a trend of spatial agglomeration. The urban agglomerations of the eastern region showed a low-value agglomeration phenomenon, and the urban agglomerations of the central and western regions showed a trend of high-value agglomeration. (3) Economic development level (PGGDP), technological progress (TP), industrialization level (IND) and human capital (HC) can play a positive role in promoting the improvement in CEP, and population structure (PD) and energy structure (ES) can play a negative role in promoting the improvement in CEP. Industrial agglomeration (IA) and CEP show a “U"-shaped relationship that first inhibits and then promotes. In addition, foreign direct investment (FDI), IND, and HC have significant spatial spillover effects on neighboring cities.

电网发生故障后充分利用报警信息对故障元件进行判别,是保障电力系统安全运行的重要环节.针对现有Petri网时序推理与置信度推理相分开、计算过程复杂且未充分利用时间信息等问题,提出了一种基于加权模糊的时序约束Petri网电网故障诊断方法.将时序约束引入到Petri网的库所与变迁中,根据保护与断路器之间的动作顺序关系建立加权模糊的时序约束Petri网模型.定义置信度与时间区间分层推理运算,实现置信度推理与时序推理同步进行,在置信度推理过程中充分考虑到时间信息的影响.通过对多组算例仿真比较得出,所提方法能够有效判别出故障元件,具有较高的准确性和容错性.

基于西部大开发二十年的战略基点,采用基于非期望产出超效率的SBM模型测度我国西部大开发过去二十年(2000-2020年)以来的能源效率,并以测算结果为基础,采用Tobit模型对贵州省能源效率的影响因素进行分析.结果表明:西部地区能源效率在2000年后呈现下降趋势并在2016年后呈现上升趋势.贵州省能源效率相较于西部地区较低.在影响因素中,经济发展水平、技术进步和环境规制对能源效率起正向作用;城镇化水平、能源消费和第二产业比重降低能源效率.

在对山东能源集团23个煤矿进行调研的基础上,从不同矿业集团、不同煤炭产区、不同生产能力3个视角对比分析了煤炭企业生产成本.研究发现:各个矿业集团的管理费用和销售费用差距较大,具有一定的降本空间;未来山东省煤炭开采应进一步向济宁矿区、新汶矿区和巨野矿区集中;山东能源集团应进一步合并重组煤炭企业,提高生产能力.最后,提出了相应的降本提效对策.

中国能源分布存在显著的非均衡性,随着能源的不断开采及国家能源布局的调整,能源产能快速呈现出空间集聚的态势.在世界能源格局巨变和全球环境恶化的背景下,研究能源产能空间集聚对区域能源效率的作用机理和效应,能够为中国制定相关能源政策和能源战略提供有益指导.文章利用2000—2017年省级面板数据,通过构建能源产能空间集聚测度模型、全要素能源效率测度模型、能源产能空间集聚对区域能源效率的影响模型和中介效应检验模型,研究能源产能空间集聚对区域能源效率的作用机理和效应.结果表明:① 中国东、中、西部地区能源产能空间集聚呈收敛态势.其中,东部地区集聚度逐渐减小,西部地区集聚度逐渐增大,中部地区集聚度先增后减.② 中国区域能源效率差异明显,整体表现为东部>中部>西部的态势.③ 能源产能空间集聚对能源效率的影响具有明显的区域异质性.从全国看,能源产能空间集聚对能源效率具有显著正向效应;分区域看,东部地区能源产能空间集聚对能源效率具有促进作用,而对中、西部地区具有抑制作用.④ 能源结构和技术创新是能源产能空间集聚影响能源效率的重要因素.根据研究结论,文章提出了贯彻落实"抑制东部、控制中部、发展西部"的煤炭发展战略;加快推进中西部地区新能源发展,扩大碳交易机制范围,优化能源消费结构;大力推进中西部地区节能技术创新和节能产业发展,加大能源效率考核力度等政策建议.

在"资源诅咒"理论假说的基础上,利用2000-2019年"晋陕蒙宁新"5个煤炭资源型省区面板数据,依次开展了样本省区"资源诅咒"存在性检验、传导路径检验以及新能源打破煤炭资源型地区"资源诅咒"效应检验.结果 表明:煤炭资源型地区存在显著的"资源诅咒"效应,煤炭资源开发主要通过抑制人力资本、提升第二产业占比阻碍经济快速增长,而新能源开发利用能够有效打破煤炭资源型地区"资源诅咒"现象.

煤炭资源型区域产业体系是具有强关联特征的煤基产业体系,摸清煤炭资源型区域产业系统演化动力机制,对指导其产业转型升级具有重要意义.基于自组织理论分析了煤基产业树系统的自组织特征,进而提取了煤基产业树系统演化的内生性动力和外部激发性动力.其中,内生性动力包含价值增值动力、自组织动力和创新动力;外部激发性动力包含市场引导动力、政策引导动力和组织网络动力.然后,通过序参量选择,明确了关键驱动力即二维序参量遵循(价值增值动力,市场引导动力)—(自组织动力,政策引导动力)—(创新动力,组织网络动力)的动态演化路径.最后,构建了煤基产业树系统演化的动力机制模型,并为煤基产业树系统自组织状态演化的实现提出相关的对策建议.

我国对产业结构优化的研究多是基于国外成熟的理论,由于发展阶段、经济体制等存在差异,研究结论往往与实际情况不匹配,产业结构的动态优化研究不足.对产业结构优化的定量化研究模型从静态角度建立的多,不具有普适性.需要依据产业结构的发展规律制定动态的产业政策,进而对产业结构进行调整优化,从而实现产业间的持续协调发展.

在测度中国30省市电热行业煤炭利用效率的基础上,运用ESDA模型以及空间误差模型研究中国电热行业煤炭利用效率的空间特征以及影响因素.研究结果表明:①2001—2015年间中国电热行业煤炭利用效率水平不高,且呈现出小幅度下降趋势;30省市的煤炭利用效率均未实现有效,且存在明显差异性,呈现出东部>中部>西部的分布格局.②中国省际电热行业煤炭利用效率呈现正向空间自相关性,且存在明显的集聚状态,近邻效应显著.③中国省际电热行业煤炭利用效率的主要影响因素有工业发展水平、 产业集聚、 技术进步、 交通及政府规制.

This article has been withdrawn: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been withdrawn at the request of the Editor in Chief. Subsequent to acceptance of this special issue paper by the responsible Guest Editor Sundhararajan Mahalingam, the integrity and rigor of the peer-review process was investigated and confirmed to fall beneath the high standards expected by Microprocessors & Microsystems. There are also indications that much of the Special Issue includes unoriginal and heavily paraphrased content. Due to a configuration error in the editorial system, unfortunately the Editor in Chief did not receive these papers for approval as per the journal's standard workflow.

The coal seams in western China are predominantly formed in the lower Jurassic, with generally low strength and poor cementability, which are markedly different from the coal seams in eastern China. In addition, mining layout has an important impact on the fissure development pattern and height in weak-cemented overburden. Thus, investigating the relationship between fissure development pattern and mining layout is of great significance to mining safety. In this study, the mechanical properties of coal and rock strata in no. 3 mining area of Saier Mine, Xingjiang, China, were tested. And a numerical simulation was performed by using the Universal Distinct Element Code (UDEC) distinct element numerical simulation software. The different working face layout schemes were performed to investigate the variation patterns of overburden fissure development height, and coal pillar stress and deformation. The simulation results indicate that as the delta(W) (ratio of the working face width to coal pillar width) increases, the fissure development height gradually increases and the coal pillar horizontal displacement, vertical stress, and horizontal stress first decrease and then increase. Four empirical equations for computing the fissure development height and the horizontal displacement, vertical stress, and horizontal stress of coal pillars were obtained by using the regression analysis method. What is more, all the correlations between the above independent variables and delta(W) can be expressed as quadratic functions. The equations can not only be used as reference criteria for the working face layout design of A3 coal seam in no. 3 mining area of Saier Mine, but also are of great guiding significance to the safety of multiple-seam mining actions under confined water in western China.

煤炭资源型区域产业体系是以煤炭产业为核心逐步演化形成的关联性强的煤基产业体系,煤炭产业的转型升级将对其产生强大的波及效应,全面考虑煤基产业体系的构成要素和结构因素对煤炭产业能否有效转型具有重要意义.文章在产业链和产业网络等理论基础上,提出煤基产业树概念,并通过类比分析方法构建了煤基产业树模型;然后,分析了煤基产业树结构与功能以及演化机理;最后,从理论和实证两方面分析了煤基产业树在区域煤炭产业转型方向判别中的应用价值和路径.