International Variation in Accounting Measurement Rules and Analysts' Earnings Forecast Errors

We theorize that accounting systems affect analysts' forecast accuracy through changes in earnings variability. We argue that the matching and historical cost principles reduce earnings variability, and hence, reduce analysts' earnings forecast errors. We also argue that restricting the choice of accounting methods can result in larger forecast errors. We argue that more informative disclosure environments should reduce forecast errors. We test whether variation in these factors across countries explain variation in analysts' earnings forecast bias and accuracy. Our results indicate that these characteristics of financial accounting systems are complements, and that they affect financial analysts' earnings forecast errors.     

浅谈铣刀和铣削用量的合理选择对数控加工的影响

机械加工的目的为:高质量、高效率和低成本。数控铣床做为一种高效率的加工设备,要想充分发挥其高效的特点,与合理的生产工艺分不开,而铣刀与铣削用量的合理选择是生产工艺中不可缺的一部分。合理的选择铣刀和铣削用量不仅能提高加工效率而且能保证零件的加工质量。     

关于金刚石环形带锯条在硅晶圆棒切割中的技术要求及应用问题的探讨

随着太阳能光伏行业的迅速发展,硅太阳能电池已经得到大规模应用,并在工业生产中占据主导地位,从而金刚石环形带锯条也广泛应用在硅材料的加工中。文章对金刚石环形带锯条在硅晶圆棒切割应用中的技术要求及使用中常出现的一些问题进行了分析和探讨。     

Bounding endogenous regressor coefficients using moment inequalities and generalized instruments

The main approach to deal with regressor endogeneity is instrumental variable estimator (IVE), where an instrumental variable (IV) m is required to be uncorrelated to the regression model error term u (COR(m,u)=0) and correlated to the endogenous regressor. If COR(m,u)≠0 is likely, then m gets discarded. But even when COR(m,u)≠0, often one has a good idea on the sign of COR(m,u). This article shows how to make use of the sign information on COR(m,u) to obtain an one‐sided bound on the endogenous regressor coefficient, calling m a ‘generalized instrument’ or ‘generalized instrumental variable (GIV)’. If there are two GIV's m₁ and m₂, then a two‐sided bound or an improved one‐sided bound can be obtained. Our approach is simple, needing only IVE; no non‐parametrics, nor any ‘tuning constants’. Specifically, the usual IVE is carried out, and the only necessary modification is that the estimate for the endogenous regressor coefficient is interpreted as a lower/upper bound depending on the prior notion on the sign of COR(m,u) and some estimable moment. A real data application is done to Korean household data with two or more children to illustrate our approach for the issue of child quantity–quality trade‐off.     

计算机在实践中的运用

介绍了如何对紫金Ⅱ微机进行改进,使其既保持原有的性能(用高级语言编程)又具有单片机的工控特性。举出了用于控制通风管道温度参数的成功例子。     

大型矿井动力操控员工安全心理参数探究

随着矿产资源不断向地层深部开采，矿井亦不断延伸，尤其是千米深井日渐增多，矿井动力提升速度和提升功能不断加快、增强，矿井数字化水平提高，对矿井动力操控员工的心理反应能力、注意能力、时空判断能力等一系列心理素质水平的要求不断增强。员工的反应准确性、注意集中和分配能力及情绪稳定性和人格状况是构成影响员工操控行为安全稳定的核心心理品质。探究矿井动力提升系统操控员工的各项安全心理阈限值及其安全心理参数标准，建立员工安全心理选拔准入制，是保障矿井人一机和谐安全运行的重要措施。     

Wars and capital destruction

In this paper, we propose a theoretical framework to investigate the impact of conflicts and wars on key macroeconomic aggregates and welfare. Using a panel data with 9 countries from 1870 onwards, we first show that the consumption-to-output ratio is minimal during WWII for participants. While this can be explained by an increase in public spending in the USA, this cannot be the case in other countries that participated in WWII, as they experience a large fall in output during wartime. To account for this, we build a variation of a Real Business Cycle model first proposed by Hercowitz and Sampson (1991). We extend the initial model to account for specific shocks that destroy private and public capital stocks – as conflicts do – by assuming an (exogenously) time-varying parameter in the law of capital accumulation. In addition, the model imbeds generalized TFP shocks capturing standard technological factors as well as the potential effects of war on the labor force. The model is estimated and used (i) to assess the importance of capital shocks during war episodes, and (ii) to quantify the welfare effects of conflicts. We show that capital shocks are crucial to account for the macroeconomic dynamics of countries that have experienced large war-related destruction, and that the welfare losses from fluctuations can be quite large when considering data samples that include major war episodes.     

兰尖铁矿无底柱分段崩落法结构参数研究与确定

本文对兰尖铁矿无底柱分段崩落法结构参数的选择进行了研究分析,指出了参数选择的依据,对其它类似矿山选择结构参数提供了参考。     

几何参数对空心楼板刚度的影响研究

本文采用ANSYS软件,以肋宽、肋高、底板和顶板厚度等构造参数为变量建立了系列有限元模型,分析研究了这些参数对现浇混凝土空心楼板刚度的影响大小和规律。为空心楼板的设计提供参考。