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1.
This paper investigates why the upsurge of top income shares has coincided with economic slowdowns in the US since the late 1970s. I argue that a fast-growing unearned income from ‘wealth residual’ – the unexplained increase in wealth that is not accompanied by any increase in real output – lies behind them. To support this hypothesis, I measure wealth residual from the national accounts and associated statistics, and then perform a set of panel regressions using a comprehensive panel dataset of the US at the state level. The estimation results demonstrate that the rapid growth of wealth residual during the last four decades has contributed to a co-evolution of fast-growing inequality and falling growth. 相似文献
2.
王秀芬 《中小企业管理与科技》2021,(9)
对于城市轨道交通来讲,在运行的过程中,直流牵引供电系统是使用最为主要的部件之一。在该系统应用的过程中,接触网残压问题是较为严重的问题,也是当前所出现问题当中比较普遍的一种。对于直流牵引供电系统来讲,当出现接触网残压问题时,可能会对人的生命安全造成严重威胁,同时也会使检修施工和接触网送电保护闭锁等相关工作受到影响,严重拖慢工作进度。因此,论文通过测试、仿真分析和模拟验证等方法,对城市轨道交通直流牵引供电系统接触网残压问题进行了研究与论述。 相似文献
3.
为摸清猕猴桃中有毒有害物质的残留动态,确保出口产品质量安全符合主要贸易国官方要求,本文采用气相色谱-质谱法,测定施药后不同时期苯醚甲环唑在猕猴桃果实中的残留量,并依据残留消解动态,按照欧盟和日本食品安全卫生标准,对10%苯醚甲环唑水分散粒剂的使用安全性进行评价。结果表明,苯醚甲环唑在猕猴桃中的残留量随着时间的推移逐渐下降,动态曲线符合一级动力学方程C_t=0.5359e-0.184t,半衰期为3.767 d,属易消解农药;按照欧盟和日本猕猴桃农药最大残留限量要求,10%苯醚甲环唑水分散粒剂按照推荐剂量单次施药,10天后采摘食用是安全的。 相似文献
4.
5.
This paper reports the results of a scientific survey of the equity valuation practices of CFA Institute members with equity analysis job responsibilities. Using an instrument designed to minimize biases in prior valuation surveys and sampling a larger group than in previous studies (13,500 investment professionals, resulting in 1,980 valid completed questionnaires), this paper documents professional practices in the selection of equity valuation approaches, including specific model variations and key input preferences. Important differences in practice were observed across geographies and employer firm types. 相似文献
6.
新疆棉农残膜回收行为影响因素及实证研究*——基于棉农的调研数据 总被引:1,自引:0,他引:1
[目的]为响应农业农村部“农业绿色发展五大行动”,加强农业面源污染防治,缓解新疆棉田残膜危害,基于新疆棉农的问卷调查研究棉农的残膜回收行为。[方法]采用描述性统计和Logistic回归模型分析影响新疆棉农残膜回收行为的因素。[结果](1)新疆农用地膜回收率低,地膜污染形势严峻。(2)棉农对残膜危害认知缺乏,对残膜回收的间接价值认识不足,影响新疆残膜回收效率。(3)残膜回收的成本收益是影响棉农残膜回收行为的关键因素,其他如棉农年龄、种棉年限、对残膜危害的认知等自身特征,以及农户劳动力数量、政府对残膜污染的关注程度等因素对棉农的残膜回收行为有重要影响。[结论]网络及电视广播等现代媒体对棉农的残膜危害认知水平有较大影响,棉农更愿意采用成本更节约的焚烧、堆地的残膜处理方式。因此提出引导棉农残膜回收、提高棉田残膜回收效率的对策建议。 相似文献
7.
Land greening in China is regarded as contributing a great deal to greening of the Earth. The phenomenon is mainly attributed to climate change, arising atmospheric CO2 and ‘Grain for Green’ (GFG) land management policies. However, limited knowledge is known how much land greening is from contributions of the GFG practice. Therefore, the study took the typical region of the GFG practice, the Loess Plateau, as the study area, and used 1982–2015 satellite-observed GIMMS3g normalized difference vegetation index (NDVI) data, ERA-Interim climatic variables (precipitation, temperature and solar radiation) and atmospheric CO2 concentration data with the help of a developed TPRC-based NDVI model to derive GFG-induced NDVI after 1999. Furthermore, this study tracked the spatial-temporal dynamics of GFG-induced NDVI and assessed contributions of the GFG practice to regional vegetation changes. Results showed that satellite-observed NDVI and TPRC-based NDVI both exhibited an increasing spatial pattern from the northwestern to southeastern Loess Plateau, but their greening trends were separately 0.0022 and 0.0009 per year in 1982–2015 (p < 0.05). Note that the satellite-observed greening trend was much steeper with a slope of 0.0056 per year after 2006 (p < 0.05). The subsequent analyses documented that GFG-induced land greening were largely responsible for the steep trend. In space, evident greening patterns began to be observed in the central Loess Plateau from 2006 to 2008, afterwards expanded towards eastern and southwestern Loess Plateau. In 2011–2015, the increase magnitude of GFG-induced land greening in the Loess Plateau averagely accounted for 8.5 % in comparison to estimated TPRC-based NDVI, but in six natural zones were various, ranging from 3.2%–15.7%. In some regions of central Loess Plateau, GFG-induced NDVI contributed even more than 20 % to vegetation increase. This study highlights that land use management contributes more to land greening dynamics over the Loess Plateau compared to climate change and arising atmospheric CO2 concentration. These findings likely provide some valuable information for curbing or enhancing specific-location vegetation changes in future regional land management and planning. 相似文献
8.
In this paper, we consider portmanteau tests for testing the adequacy of multiplicative seasonal autoregressive moving‐average models under the assumption that the errors are uncorrelated but not necessarily independent. We relax the standard independence assumption on the error terms in order to extend the range of applications of the seasonal autoregressive moving‐average models. We study the asymptotic distributions of residual and normalized residual empirical autocovariances and autocorrelations under weak assumptions on noise. We establish the asymptotic behavior of the proposed statistics. A set of Monte Carlo experiments and an application to monthly mean total sunspot number are presented. 相似文献
9.
Alexander William Salter 《Economic Affairs》2016,36(3):294-308
I develop a robust political economy of bureaucracy by highlighting the conditions necessary for hierarchical administrative bodies to govern protectively and productively, but not predatorily. These conditions are residual claimancy and jurisdictional competition. I make this argument by exploring a post‐cameralist interpretation of governance. Cameralism arose as a governance philosophy in the fractured principalities of seventeenth‐century Germany following the Thirty Years' War. Post‐cameralism focuses not on particular cameralist governance strategies but on a paradigm which sees governance as an activity provided within a larger exchange order, rather than imposing itself on that order as in more conventional treatments of public economics. While a post‐cameralist conception of governance comes with its own challenges, such as tensions with normative visions that promote self‐governance, it nonetheless presents an intriguing synthesis of monocentric and polycentric insights. 相似文献
10.
介绍了亚麻油的加工技术、亚麻籽粕中的有害成分、亚麻油的保健功能以及选择与传统溶剂不同的两相溶剂系统分离有毒成分生氰葡糖苷的方法,并对分离效果和影响分离效果的操作参数进行了分析比较,得出了最佳浸出溶剂系统的操作参数。 相似文献