输出理论对大学英语口语与写作教学的启示

输出理论是指在学习第二门语言遇到问题时会促使我们进一步学习这种语言的理论。正因为意识到了学习时遇到问题,学习者就会改善它的输出,从而学习有关这门语言的新知识。尽管苏安宣称这种输出并不是第二语言知识获得的唯一途径,但在语言产生的相关大脑活动中,输出理论促使了第二语言的学习,它有别于输入理论,却又可以加强输入。本文在介绍了苏安的输出理论的基础上,阐述了这一理论对英语口语和写作教学的指导意义。     

集体林权改革下的林业经济增长因素分析——以辽宁省为例

根据1982～2008年辽宁省林业经济发展的相关数据,采用C-D生产函数模型,实证分析了林业投资、劳动力、林业科技进步、产权制度等要素对辽宁省林业经济增长的影响。结果表明,集体林改下辽宁省林业经济整体呈快速上升趋势,27年间资本、劳动力、科技进步的产出弹性分别为0.4,0.55,0.06,对经济增长的贡献率分别为37.7%,19.15%和43.15%,林改作为政策制度因素对于林业经济增长具有正向的推动作用。     

Structural change and blurred sectoral boundaries: assessing the extent to which knowledge-intensive business services satisfy manufacturing final demand in Western countries

This paper focuses on the vertical integration of knowledge-intensive business services (KIBS) into manufacturing sectors, using a subsystem approach to input–output analysis. It aims at correctly assessing the process of structural change that has occurred in the four main European countries (France, Germany, Italy and the UK) over time (1995–2005). It does not focus on KIBS sectors per se, but on their function as carriers and sources of knowledge which influences the performance of sectors, value chains and clusters across industries and within countries. The analysis shows that KIBS’ contribution to satisfying the final demand of manufacturing is in general largely underestimated; that KIBS vertical integration into manufacturing has increased over time in all the countries investigated except the UK; and that the extent to which manufacturing sectors outsource to KIBS is significantly affected by their technological intensity.     

Intensidad en empleo a largo plazo del crecimiento del producto sectorial en Túnez

Se examina la capacidad a largo plazo de Túnez de generar empleo. Con datos de panel de 15 sectores económicos de 1983–2010, los autores estiman sus elasticidades producto‐empleo a largo plazo utilizando el estimador de media grupal. Según sus resultados, la política económica debería orientarse a los sectores más intensivos en empleo: servicios y manufacturas exportadoras. Destaca la incapacidad del sector minero de absorber mano de obra, por lo que la inversión en el mismo no será productiva; asimismo, el crecimiento sin empleo a largo plazo de la hotelería y restauración induce a pensar que deberían fomentarse más las actividades paraturísticas que las turísticas.     

SENSITIVITY AND UNCERTAINTY ANALYSIS IN MRIO MODELLING; SOME EMPIRICAL RESULTS WITH REGARD TO THE DUTCH CARBON FOOTPRINT

Environmental multi-regional input–output (MRIO) models require large amounts of data that all have their specific uncertainties. This paper presents a sensitivity and uncertainty analysis in order to gain an understanding of the directions in which efforts should be made to reduce these uncertainties. The analyses were carried out for an MRIO model to calculate the Dutch carbon footprint. A sensitivity analysis of the technical coefficients showed that changes in the coefficients in the domestic blocks and in the Dutch import blocks had the largest effects on the calculated footprint. The uncertainty analysis consisting of a Monte Carlo simulation based on probability distributions around the model coefficients showed a relatively low degree of uncertainty in the total Dutch carbon footprint; uncertainties in the carbon emissions allocated to regions, sectors and products were larger. Both analyses showed that, in certain cases, it is justified to apply a partial MRIO analysis.     

UNDERSTANDING THE INTERACTION BETWEEN INTERNATIONAL AND EURO AREA OUTPUT VOLATILITY

This paper addresses two main questions. First, it seeks to establish whether the stylized facts of the ‘great moderation’ that have been documented for the UK and US economies can be found for the Euro area. Second, it explores possible explanations for any changes that have occurred in the volatility of Euro area output fluctuations. In examining why business cycles have moderated, much of the existing literature has tended to concentrate on a few key factors. These include shifts in the structure of the economy, improved monetary policy and a ‘good luck’ factor. This paper, however, follows a relatively new branch of the great moderation literature by focusing on whether international business cycle linkages have changed in a way that may have perpetuated the dampening in Euro area output fluctuations. The results show Euro area output fluctuations to have significantly reduced in variability over the last quarter of a century. The results go on to highlight that, although Euro area cycles differ little from rest of the world cycles, the moderation in Euro area output fluctuations is only marginally due to changes in international business cycle linkages and smaller international and domestic shock variances.     

TRADE INTEGRATION,OUTSOURCING AND EMPLOYMENT IN AUSTRIA: A DECOMPOSITION APPROACH

Outsourcing and trade integration of advanced countries is debated with respect to employment effects, in particular for low educated workers – at least in relative terms. We study the employment effects – differentiated by educational attainment levels – of changes in the patterns of trade integration and outsourcing in the Austrian economy over the periods 1995–2000 and 2000–2005 using hierarchical decomposition analysis based on deflated input–output tables. Outsourcing is modeled as changes in the shares of domestically produced intermediates in total intermediates. A similar decomposition of the final demand vector allows us to draw conclusions on the overall employment effects of trade integration. The results suggest that the expected negative employment effects of outsourcing and rising import penetration have been overcompensated by increasing exports. Thus, the overall employment effects of Austrian trade integration have been positive for all educational attainment groups. However, whereas the total effects have been strongest for medium and high educated workers over the period 1995–2000, employment of low educated workers have been strongest and positively affected over the period 2000–2005. This pattern can be explained by a more sluggish export performance together with stronger negative effects of outsourcing and import penetration in medium and high-skill intensive products.     

财政受托责任的理论分析

有效实现财政受托责任,首先必须明确政府各部门的财政受托责任;其次应该有正式的法律制度来保证财政受托责任的实现。针对责任的回应性,狭义政府部门的财政受托责任主要通过产出预算来实现。     

集成运放的一些使用技巧

目前集成技术飞速发展且集成芯片已被广泛应用 ,为了充分利用集成在一个芯片上的两个运算放大器性能互相匹配的特点 ,本文从三个方面介绍了合理使用集成运算放大器的几种技巧。其中 ,利用集成在一个硅片上的两个运算放大器的输入失调电压极其温度漂移相互补偿的原理 ,组成了失调电压极低的运算放大器 ;根据输入电阻的自举扩展原理 ,利用集成在一个硅片上的两个运算放大器组成的反向比例运算放大器具有很高的输入电阻和较高的电压放大倍数 ;根据差动放大电路的输出电压方式 ,利用集成在一个硅片上的两个运算放大器组成的差动输出运算放大器 ,最大线性输出电压范围比一个集成运算放大器的最大线形输出电压范围大一倍。且适用于不接地负载。