Reduction in nitrogen fertilizer use results in increased rice yields and improved environmental protection

Overuse of nitrogen fertilizer represents a considerable environmental problem globally, but especially in China. Recently, a recent approach on an experimental scale based on the diffusion of the so-called Three-Control Technology (TCT) successfully alleviated the overuse of nitrogen fertilizer in southern China villages in the Guangdong Province, serving as a reference point for other rice-producing countries tackling similar challenges. Here, we assessed the correlation between rice yields and reduction in the use of nitrogen fertilizer following the introduction of TCT. Our study was based on the collection of primary data from 248 households randomly selected from four rice-growing areas of Guangdong Province, China. Our results show that TCT significantly improved the efficiency in the use of nitrogen. Crucially, participating farmers, including both full adopters and partial adopters, were found to fundamentally change their application practices of nitrogen fertilizer, resulting in major improvements in the local soil and water systems.     

候变化对我国种植业化肥投入的影响

气候变化不但会对农业产出产生影响，而且还会对农业生产要素投入产生影响。利用我国26个省2001—2012年的面板数据，实证分析气温和降水量变化对我国种植业生产中化肥使用强度的影响，结果表明：从整体看，年平均气温上升有助于降低化肥的使用强度，而年降水量的增加则会提升化肥的使用强度；对于热带亚热带季风气候区，降水量增加、气温上升均会导致化肥使用强度增加；对于温带季风气候区，气温上升会导致化肥使用强度下降，但是降水量增加对化肥使用强度的影响不显著。气候变化对不同气候区农业生产的化肥投入具有不同的影响，因此有关化肥控制的政策有必要考虑气候因素的影响，政策目标的设定也应体现区域差异。     

Balancing the risk of ‘Lazearian’ interrupters and the benefits of educational and social peers: tracing parental preferences for class-size reduction

Using Danish survey data from a choice experiment, parental preferences for class-size reduction are estimated. While parents with children in large classes are willing to pay for class-size reduction, parents with children in small classes are reluctant and even express negative utility for further class-size reduction. We interpret this as parents balancing the risk of ‘Lazearian’ interrupters and the benefits of educational and social peers when forming their preferences for class size.     

Kernel-type estimators for the distortion risk premiums of heavy-tailed distributions

A new kernel-type estimator for the distortion risk premiums of heavy-tailed losses is introduced. Using a least-squares approach, a bias-reduced version of this estimator is proposed. Under suitable assumptions, the asymptotic normality of the given estimators is established. A small simulation study, to illustrate the performance of our method, is carried out.     

农田污染对粮食生产的影响研究——以四川为例

作为农业生产的根本,农田质量对于粮食生产而言至关重要,因此农田污染的相关防治已经成为我国农业可持续发展、农产品安全以及我国生态环境保护的重要措施。目前我国农田污染主要特征为农田污染物成分复杂,农田污染程度不断扩大。同时由于农田污染导致土壤肥力下降进而导致相关农作物的产量以及品质不断下降。文章以四川省为例,探究农田污染对粮食生产的影响,结果发现,目前四川省农田污染主要来源于农药化肥的不合理使用,水体以及土壤受工业废水污染严重,畜牧业废弃物污染等。农田污染导致可耕种土地面积不断减少,粮食生产受到严重影响。基于此,该文针对四川省农田污染现状提出农田污染综合立体防控策略,并在此基础上通过合理规划农业生产,减少农药化肥使用量,提高生物防治在病虫害防治当中的比例等措施减少农田污染对粮食生产的影响,以期为我国农田保护以及粮食生产提供一定的理论以及政策依据。     

The role of openness in the fuzzy front-end of service innovation

The early stages of innovation involve high levels of uncertainty, leading to it being labelled as the “fuzzy-front end” (FFE). Although openness has been identified as pivotal to innovation performance in the open innovation literature, little effort has been put into exploring its role in the FFE. Specifically, this study examines ‘openness competence’ within the FFE–i.e., the ability of a FFE team to explore, gather and assimilate operant resources from external sources by means of external searches and inter-organisational partnerships. The aim is to investigate the impact of openness competence on front-end uncertainty reduction and service innovation success. Data were obtained from a survey of 122 IT-based service innovation projects implemented by IT service provider firms in Thailand. The results suggest that openness competence positively influences both the degree of uncertainty being reduced during the FFE and the overall success of service innovations. These findings offer several implications for research on open innovation and the FFE as well as encouragement to managers to apply a more open approach to the FFE of their service innovation projects.     

铁离子、亚铁离子变化对工业锅炉酸洗的影响

介绍工业锅炉酸洗中铁离子的来源,并以实例说明酸洗中应强化对铁离子、亚铁离子(Fe3+、Fe2+)的化学监测,使锅炉酸洗安全进行,及终点的判断。     

路基稳定性数值分析

本文通过对常见的路基稳定性分析案例进行强度折减法的数值分析,为进一步研究这一方法在路基稳定性分析中的应用奠定基础。     

Reducing High Public Debt Ratios: Lessons from UK Experience*

This paper examines contrasting experiences of the United Kingdom in addressing high public debt to GDP ratios following major wars. A clear message is that interest rate / growth rate differentials were more important than primary budget surpluses for the different outcomes. The debt to GDP ratio fell very rapidly under financial repression following the Second World War but remained stubbornly high despite large budget surpluses with price deflation after the First World War. Implications for policymakers today are that averting price deflation is a high priority and that supply‐side policies that raise growth could play an important part in debt reduction.     

我国各区域农业生产资源配置效率分析

本文运用数据包络分析法测算了我国各区域农业经济的投入产出效率,指出目前我国各省市农业经济资源配置效率差异较大,其中人均化肥施用量对全国大多数省市农业劳动生产率都是最重要的,这种生产方式属于典型的“化肥农业”,并由此引发了一系列问题。文章认为,制度创新可以再造农业经济主体之间的相互关系,减少信息成本和不确定性,降低交易成本,提高生产要素配置效率,从而促进农业经济快速增长;在制度创新先行的前提下,实现农业经济组织创新与制度创新、知识创新的互动,是转变“化肥农业”生产方式,走可持续的新型农业发展道路的关键所在。