A Disaggregated Econometric Model Based on Flexible Functional Forms

This paper introduces an econometric input—output model for Western Germany in a disaggregation of 12 commodities and sectors. The ‘Jorgenson’-type equilibrium model is based on flexible functional forms on the supply and on the demand side of the commodity markets. For intermediate demand, the relationship between the translog function and its special cases—the Cobb-Douglas function— is exploited. Prices and production are endogenized by market-clearing conditions. The fully integrated model also endogenizes capital accumulation, a rudimental govern-ment budget and income distribution, as well as wages and labour demand on rationed labour markets. The results of a dynamic ex post simulation show that the model is able to depict the sectoral economic development in Germany in the sample period from 1970 to 1986.     

Valuing customers for social network services

In the current Internet environment, many online service companies based on community factors (networks) produce and sell new types of digital products. For example, SNS (social network service) companies now sell customers digital decorative products for the adornment of online avatars. Not only do individual customers consume these digital products, but they also exchange them as gifts in their local neighborhoods. While previous studies on customer valuation (e.g. CLTV, RFM, etc.) focus on some important issues for identifying valuable customers, the literature does not resolve issues related to the effects on customer value of products purchased as gifts for another person. This study attempts to verify empirically the effects of two representative social network properties (tie strength and the number of ties) on customer monetary value.This study selects 2615 customers from a South Korean SNS website who enrolled on the site on the same day. Data include diverse purchase-related information, social network properties in terms of gift-giving for six months, and demographic information. The primary results of this study are as follows. First, the proposed model, which includes social network properties, has a great deal more explanatory power than the baseline model — the RFM-based customer value model. Second, tie strength and the number of ties in a gift-giving network increase customer value. Third, tie strength has a more profound impact on customer value than does the number of ties. The results of this study theoretically expand the domain of customer valuation studies due to the inclusion of social network properties, and suggest important practical implications for some online SNS companies in their efforts to find valuable customers and improve customer value.     

Effective experimental controls for research in international accounting: Further thoughts

This paper responds to recent research by Ruland et al. [Ruland, W., Shon, J., Zhou, P., 2007. Effective controls for research in international accounting. Journal of Accounting and Public Policy, 26(1), 96–116.] that addresses the effectiveness of experimental controls for research in international accounting, with focus on Ndubizu and Sanchez [Ndubizu, G.A., Sanchez, M.H., 2006. The valuation properties of earnings and book value prepared under US GAAP in Chile and IAS in Peru. Journal of Accounting and Public Policy 25 (2)]. We attempt to remove some misconceptions about effective experimental controls that have surfaced in the debate. We argue that theory and refined proxies alleviate many of the control issues that have surfaced in the literature.     

The "Invisible Hand"

The argument of the "Invisible Hand" is that the system of free enterprise benefits society in general even though it is not the aim of any particular economic agent to do that. This article proposes an analysis of why this is so. The key is that the morality of the market forbids only force and fraud; it does not require people to do good to others. Nevertheless, when all transactions are voluntary to both parties, that is exactly what we can expect to happen. This is both because the sum of the benefits of innumerable transactions, which are beneficial to both parties, is very great, but also and especially because of Positive Externalities. People use the particular products and services they get in market exchanges in ways that benefit others in ways not at all foreseen by the agents to those transactions at the time. These externalities range from the benefits of invention and ingenuity to the exercise of charity and philanthropy, all of which flourish in developed capitalist societies.     

聚合物产品质量监督检验方法及应用

介绍了目前大庆油田聚合物驱应用的聚合物产品质量监督检验方法，对其检验原理、改进情况，以及应用现状做了系统说明。     

Mean reversion in annual earnings and its implications for security valuation

This article documents the long-horizon mean reverting character of annual earnings and tests the implications of such mean reversion for security valuation. First, both theory-based and nonparametric measures of earnings persistence decrease as the estimation order increases, revealing 40 percent less long-horizon persistence than expected under the commonly used random walk model. Second, the return responses to the earnings shocks are more closely related across firms to the higher-order measures of persistence that reflect significant long-horizon mean reversion. Third, the persistence measure derived from classical valuation theory outperforms the generic measure in explaining the return responses. Taken as a whole, these results provide evidence for significant mean reversion in the higher-order properties of earnings and for the stock market incorporating these properties in a manner consistent with classical valuation theory.     

高羊茅纤维制取与结构性能研究

纺织纤维材料在近一个世纪的发展中,不仅在数量上有了巨大的发展,而且在纤维品种、性能上都有了突飞猛进的发展。但是,纤维材料产量的增加,主要依赖化学纤维的产量增加,而化学纤维原料主要是来源于石油、煤和天然气等有限的矿物资源,而这些有限的矿物资源的枯竭是可以预见的。[1]开发利用植物纤维是满足我们对纤维需求的一种有效途径。我国每年绿化用草修剪后废弃的草屑数量可观,大多被遗弃,造成资源浪费。开发利用植物纤维,既不会污染环境,又能够重复利用,符合纺织行业可持续发展的要求。     

Agricultural price transmission across space and commodities during price bubbles

This article investigates agricultural price transmission during price bubbles. The empirical approach concerns the horizontal transmission of cereal prices both across different market places and across different commodities. The trade policy intervention put forward to mitigate the impact of price exuberance is considered. The analysis is performed using Italian and international weekly spot (cash) price data over years 2006–2010, a period of generalized turbulence of agricultural markets. Firstly, the properties of price time series are explored; then, interdependence across prices is specified and estimated by adopting appropriate cointegration techniques. Results suggest that the bubble had only a slight impact on the price spread and the temporary trade‐policy measure, when effective, has limited this impact.     

铝硅镀层22 MnB5高强钢高温拉伸性能及本构模型

为了分析和表征热成形用的铝硅镀层22MnB5高强钢的热变形行为,采用Gleeble-3800热模拟试验机,在成形温度750～900℃、应变速率0.1～10 s~(-1)试验条件下实施了铝硅镀层22MnB5高强钢的板材等温拉伸试验,采用双曲正弦型Arrhenius本构模型描述铝硅镀层22MnB5高强钢的高温流变行为,并考虑应变影响构建了模型。结果表明:1)铝硅镀层22MnB5高强钢的真应力随成形温度的升高而降低,随应变速率的增大而升高,在高温低应变速率条件下(900℃,0.1 s~(-1)),峰值应力为134.24 MPa;在低温高应变速率条件下(750℃,10 s~(-1)),峰值应力为381.25 MPa; 2)本构模型预测值与等温拉伸试验值线性拟合的相关系数R~2为0.978,表明构建的本构模型在整个应变范围具有良好的预测精度。研究成果能够准确表征铝硅镀层22MnB5高强钢的热变形行为,为其数值模拟提供材料模型数据支持,并为其热加工工艺研究提供了参考。     

鸢尾属植物抗旱生理指标的测定

利用聚乙二醇(PEG-6000)以10%、20%、30%三个浓度,将四个品种鸢尾植株进行浸根处理,作为模拟土壤干旱胁迫。测定结果表明:马蔺具有较强的抗旱性。质膜透、MDA含量和SOD活性含量是鸢尾属植物重要的抗旱生理指标。