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101.
通过统计分析得出影响建筑业碳排放强度的13个影响因素,基于收集的京津冀相关数据,运用逐步回归分析找出其中6个关键因素.借鉴五折交叉验证解决数据稀缺问题,采用神经网络对京津冀建筑业碳排放强度进行预测.利用敏感性分析简化模型,筛选出4个核心因素.结果表明,此模型预测精度高达99%,同时根据挖掘出的核心因素和关键因素,提出建筑业节能减排的建议.  相似文献   
102.
In this paper, we consider the feasibility of constructing online sentiment indices, using large amounts of media data, as an alternative to the conventional survey method used to create the consumer confidence index in South Africa. A clustering framework is adopted to provide an indication of possible candidate sentiment indices constructed from a combination of different text sources and dictionaries that best mimic the traditional survey-based consumer confidence index from the South African Bureau for Economic Research (BER). The results conclude that it is possible to create an index using sentiment analysis using online editorial data that does resemble the BER’s consumer confidence index. The different media-based sentiment indices (MSI) show a significant level of correlation and co-movement with the BER’s CCI. Impulse responses and cross-correlation functions indicate that the MSI could potentially lead the survey-based method up to two quarters. Furthermore, Granger-causality tests show that the media-based indices are good predictors of future consumer confidence index values. The results provide motivation for further study on the use of sentiment-based techniques and online media data sources to track consumer confidence within an emerging market such as South Africa.  相似文献   
103.
The Great East Japan Earthquake created health hazards for many people. Using Panel Data gathered in Iwanuma city, Japan, at two points in time (in 2010 before the quake, and in 2013 after the quake), we found that the high degree of housing damage negatively affected victims’ self rated health (SRH) (direct effect), and decreased the levels of their social connections, which in turn also had a harmful effect on their SRH (indirect effect). We also found that although the direct impacts of earthquakes disappear relatively quickly, the harmful indirect effects associated with a decrease in social connections are slower to dissipate. We conducted a first-difference two-step GMM estimation to consider the possible problem of endogeneity. The results support the above conclusion, and show that in the short-term, the indirect impacts of the earthquake accounted for 55 % of all the impacts experienced.  相似文献   
104.
This paper aimed to present an original approach for solving the aircraft stand allocation (SA) problem dynamically when due to operational disturbances, the planned allocation cannot be accomplished. The proposed Multiple-criteria Dynamic Stand Allocation (MDSA) method uses fuzzy logic to support decision-making under uncertainty. The MDSA method provides effective solutions in a short time, necessary for traffic management in case of delays, emergency, and untypical cases. It considers partially conflicting points of view of different airport users (airport managers, air traffic controllers, airlines, handling agents, and passengers) and may significantly support managers on the SA problem. The approach proposed can also be used for creating an initial SA plan for a considerable number of aircraft.  相似文献   
105.
This paper discusses the determinants of China’s outward foreign direct investment (OFDI) with a special focus on the role of government policy. In particular, we investigate the types of policies that are most influential in promoting OFDI. Our main contribution is to analyse, for the first time, China’s OFDI policies by means of quantitative indicators. We refine policies definitions and distinguish between Regulation Policies, Service Policies, Promotion Policies and Supervision Policies, and we develop a methodology for collecting, screening and coding policies; then we create new indices to capture different types of policies. We find that Regulation Policies, Service Policies and the general attitude of the government have significant effects on China’s OFDI at the national level.  相似文献   
106.
The credit risk contagion of Internet peer-to-peer (P2P) lending platforms is an important part of Internet financial risk management and supervision. This study analyzes the contagion path of credit risk in Internet P2P lending. Based on complex network theory and the theory of infectious disease dynamics, the characteristics of Internet P2P lending development are combined to construct a SEIR model of credit risk transmission among Internet P2P lending platforms with time lag, and the robustness of the model is analyzed and proven. The influence of platform correlations, the susceptible immune rate, the platform elimination rate, contagion latency, the saturation coefficient, and the susceptibility input rate on credit risk contagion behavior among Internet P2P lending platforms is analyzed, using the equilibrium point and threshold value. The impact of each variable is analyzed by simulation. Corresponding countermeasures and suggestions are proposed to prevent and control credit risk contagion among these platforms.  相似文献   
107.
[目的]分析评价江苏省现有农田保护经济补偿政策绩效与空间差异对建立完善长效的农业生态补偿机制和推动我国农业生态环境的可持续发展具有重要意义。[方法]以江苏省为研究区域,运用熵权-TOPSIS法,选取2010—2017年全省及苏北、苏中、苏南三个区域内11个指标,计算江苏省及三大区域农田保护经济补偿政策综合绩效值与经济、生态和社会效益单项绩效值,进行比较分析。[结果](1)江苏省农田保护经济补偿政策在2010—2017年8年综合绩效值由0189波动增长到0841,效果初现且具有较强推广价值。(2)经济效益绩效值以年均257%的增长率由0增长到1,效果最为显著,社会效益次之,生态效益自2013年后为绩效值中最低值,与前两项最大差距在05左右,反映出环境改善、农田质量提高效应远低于农户创收、社会公平效应,政策拟合度不高。(3)江苏省农田保护经济补偿政策效果存在空间差异,综合来看政策效果表现为苏南>苏中>苏北,苏南凭借经济优势在2016年和2017年的综合绩效值上比苏中苏北高出01、在经济与社会绩效值以002的差距领先且生态绩效值没有下降拐点,具有长效可持续性。[结论]现阶段农田保护经济补偿政策效果依赖地方政府经济实力,尚未形成良性长效机制,需从制度体系、环境经济手段、差别化补偿措施、农业补贴结构和宣传等5方面着手,推进农田保护经济补偿政策更好地服务生态环境。  相似文献   
108.
Airport performance differences require a better understanding of the sources of efficiency and competitive advantages. Globalization drives the air transport industry into a more market-orientated business questioning the relationship between managerial decisions and airport performance. Aviation management studies do not consider managerial capabilities and skills since they are intangible exogenous factors that are difficult to assess. In this study, a stochastic frontier analysis is performed accounting for top managers' theoretical knowledge and experience enclosed as exogenous drivers of airports' efficiency. The model analyses 12 Polish airports from 2009 to 2017. The results show a diversity of airports with a different number of passengers as efficient. The top managers' experience, when gained in the same airport, has a positive impact on airports' technical efficiency. Airports having unstable management are more technically inefficient. Independently of the efficiency level, some airports change their management after the national elections, suggesting that managers are chosen by political interest rather than by their specialised knowledge or their prior experience in aviation management. The results suggest that more practical knowledge improve airports’ performance. Airports with a majority of government ownership that are the largest ones increase their efficiency significantly, suggesting that political decisions may be discriminatory in detriment of airports managed by regional and city authorities.  相似文献   
109.
论文调查分析了近年来热度较高的跨境社交媒体平台以及相关使用数据,利用相关性分析方法分析了多个平台的数据,在此过程中发现了各平台间具有相当高的互惠性,并运用互惠比例和推广方式适配度模型完成了对跨境社交平台的运行模式以及推广方式的对比分析,最终研究得出跨境社交媒体平台的产品推广模式。  相似文献   
110.
Agriculture–nutrition linkages (ANLs) have been increasingly investigated in the literature. However, nutritional returns and costs of household agricultural production practices (APPs) in semisubsistence settings are poorly understood. We fill these knowledge gaps using pooled cross-section data sets in Tajikistan, where semisubsistence farming and undernutrition coexist despite relatively good agricultural infrastructure and education systems. Agricultural diversification, yield enhancement, production expansion are positively associated with various nutritional outcomes, particularly in areas with poor food market access. Decomposition exercises suggest that nutritional returns and costs of these APPs vary across households, and the adoption of APPs is driven by the expected nutritional returns. In Tajikistan, improving nutrition through household ANLs requires growing the smallholder agricultural sector in multiple dimensions, including diversification, intensification, and expansion, while also understanding better the pathways of ANLs and addressing bottlenecks at appropriate stages of such pathways.  相似文献   
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