中国输出了“通货紧缩”或“通货膨胀”?

本文首次采用最新发展的有向无环图等技术方法,对中国是否输出通货紧缩以及是否输出通货膨胀这一问题展开综合性、系统性的研究。研究结果表明,在通货膨胀的国际传递中,作为世界第一大经济实体的美国发挥着主导作用,与此同时,无论是在中国通货紧缩时期还是在通货膨胀时期,中国对各主要贸易伙伴国物价水平的冲击均十分微小,因此,中国并非全球通货紧缩或通货膨胀的引发因素。在此研究过程中,最新发展的有向无环图技术等方法的综合运用,在很大程度上增强了本文分析结论的可靠性与合理性。     

Impact of the Fast Track Land Reform Programme (FTLRP) on agricultural production: A tobacco success story in Zimbabwe?

The study ascertained the impact of the Fast Track Land Reform Programme (FTLRP) in Zimbabwe on tobacco production. The Chow Test, Vector Error Correction Model (VECM) and the Vector Error Granger-Causality Test were applied. The results reveal that there was a structural break in tobacco sales in the year 2000. Furthermore, in the long-run, area under tobacco production had a positive impact whilst number of tobacco producers had a negative impact on tobacco sold pre-FTLRP. Post-FTLRP, area of tobacco and number of tobacco producers had negative impact. In addition, the FTLRP induced an 8.94 % increase in the speed of adjustment in correcting the long-run equilibrium in tobacco sales. In the short-run, the FTLRP caused a percentage increase in the area of tobacco production and number of tobacco producers to induce a 0.65 % and 0.76 % increase in the tobacco sales, respectively. Area of tobacco production and number of tobacco producers Granger-caused tobacco sales in the pre-FTLRP period. Post-FTLRP, the number of tobacco growers Granger-caused tobacco sales. It is concluded that the FTLRP had an impact on tobacco sales, mainly through the number of tobacco growers. The study recommends the specialisation and training of the new farmers to improve productivity.     

《可编程控制器》课程中错误和算术标志位的理解与教学

文章介绍了可编程控制器的功能指令执行结果影响特殊标志位的状态,在教学中通过例子讲解错误和算术标志位的含义,使学生能够深刻理解和正确使用,提高教学效果。     

天然气压缩因子对流量计量的影响

探讨了速度式和容积式流量计用于天然气计量时,天然气压缩因子对其计量结果的影响;同时也探讨了无压缩因子修正或修正不当而造成的二次仪表计量误差.     

野外施工中超声波探伤检测误差的影响因素分析及对策

上油气管道安装施工中,因现场条件限制,管理环境和技术环境的恶化,使超声波探伤质量变异性增加,检测误差增大,严重地影响超声波探伤的准确性和权威性,甚至危及油气输送管道的正常生产。就野外超声波探伤检测误差增大的诸因素进行较全面的分析,并根据帕累托原理提出了相应对策,以促使上超声波务检测误差降低。     

Introducing errors in progress ratios determined from experience curves

Progress ratios (PRs) derived from historical data in experience curves are used for forecasting development of many technologies as a means to model endogenous technical change in for instance climate–economy models. These forecasts are highly sensitive to uncertainties in the progress ratio. As a progress ratio is determined from fitting data, a coefficient of determination R² is frequently used to show the quality of the fit and accuracy of PR. Although this is instructive, we recommend using the error σ_PR in PR, which can be directly determined from fitting the data. In this paper we illustrate this approach for three renewable energy technologies, i.e., wind energy, bio-ethanol, and photovoltaics.     

认购权证与标的股票间的价格相关关系实证研究

为系统分析我国认购权证市场与其标的股票市场间的价格相关关系，发现权证市场与股票市场间的联系。本文以12组样本认购权证目收盘价和标的股票的目收盘价为观测对象，运用ADF单位根检验、Johansen协整检验、向量误差修正模型（VECM）、Granger因果检验和Hasbrouck方差分解方法，考察了两个时序数列间的长期均衡关系、短期动态关系、Granger因果关系和两市在价格发现功能中作用的大小、反映信息的效率，得出了研究结论。