Efficiency Evaluation of Effect of Direct Grain Subsidy Policy on Performance of Rice Production

Using the DEA analysis method,on the basis of the national panel data from 2002 to 2014,this paper made a comparative analysis on the rice production performance before and after the implementation of direct grain subsidy policy,and made an empirical analysis on the relationship between the direct grain subsidy policy and the changes in the rice production performance. The results showed that the effect of the direct grain subsidy policy on promoting the rice production performance is declining year by year,largely because drop of scale efficiency. Besides,there are problems of serious redundancy in agricultural subsidy,unreasonable resource allocation,leading to low performance and resource waste of rice production.

Scheme of Constructing CGE Model of China's Direct Grain Subsidy Policy

This paper introduces the model of China's direct grain subsidy policy, adopts computable general equilibrium (CGE) theory, and advances the scheme of constructing the model of China's direct grain subsidy policy. On the basis of some assumptions, such as conforming to the complete competition of market, inexistence of move of capital and labor forces among countries, unchanged exchange rate and incomplete substitution, and the main body of behavior comprising representative households, producers, local government and central government, the model established in this paper includes production module and demand module. Moreover, the model takes into account equilibrium structure, the definition of profiting and macro condition for closure, the related coefficients this CGE model needs include Armingtion substitution elasticity of intermediate composite product, investment composite product and consumption composite product between import and domestic production; substitution elasticity among production factors; conversion elasticity of total sales between domestic absorption and export; elasticity of residents' expenditure; elasticity of price; elasticity of export demand; the relative share of all sectors in capital stock. This paper also points out the advantages and limitations of CGE model in analyzing direct grain subsidy policy.

Quantitative Assessment of the Impact of China's Direct Grain Subsidies on Grain Yield--Based on the Empirical Analysis of Panel Data Pertaining to 29 Provinces in the Period 2004-2007

We build the influence function empirical model of China's grain production at the present stage in view of the factors influencing direct grain subsidies,using Cobb-Douglas production function model.And we estimate the elasticity coefficient of impact of China's direct grain subsidies on grain yield,using the panel data pertaining to 29 provinces in the period 2004-2007;comparatively analyze the validity and limitation of policy factors of direct grain subsidies on China's grain yield.The results show that at the present stage,the elasticity coefficient of impact of China's direct grain subsidies on grain yield is 0.002 3,and under the existing subsidy system and level,direct grain subsidies play a positive role in increasing grain yield,but the role is limited;the elasticity coefficient of impact of the food price on grain yield is much larger than that of impact of direct grain subsidies on grain yield.Therefore,the government should strengthen and improve direct grain subsidy policies;in the mean time,pay full attention to the use of market mechanism to consolidate the basic role of the food price in promoting food security to a great extent.

Analysis of the System of Direct Subsidy for Grain Production in China

This paper introduces the status quo of the system structure of direct subsidy for grain production in China,and analyses the function and essence of direct subsidy for grain production in China as follows:the function of direct subsidy for grain production in China is to protect and promote the development of food industry,ensure food supply and national food security,protect grain growers' interests,and maintain the dominant position of national food trade;the essence of direct subsidy for grain production is the compensation for grain producers' reasonable interests,the compensation for positive externality of grain production,and social costs of adjusting equilibrium between food supply and demand.We discuss the problems existing in the system of direct subsidy for grain production in China and put forward corresponding countermeasures as follows:first,adhere to improving synergetic system of direct subsidy for grain production;second,adjust the direct subsidy method of grain production;third,establish long-term mechanism of subsidy for grain production;fourth,promote the information-based service level of the system of direct subsidy for grain production.

起动机动力涡轮叶片断裂故障研究与改进

系统归纳了动力涡轮叶片断裂故障的基本特征 ,分析了叶片断裂的根本原因在于叶片的一阶弯曲共振。在弯曲共振无法避免的情况下 ,从提高动力涡轮叶片的疲劳抗力入手 ,采用细晶 +方向性凝固 +热等静压的复合成型工艺 。

面向细粒度隐式篇章关系识别的远距离监督特征学习算法

针对中文细粒度隐式篇章关系识别进行研究。考虑细粒度篇章关系的方向性特点,提出一种基于远距离监督的特征学习算法。该算法使用远距离监督的方法,自动标注显式篇章数据,然后利用词与连词之间的相对位置信息,训练各个词的词表达,将词的修辞功能以及关系的方向性编码到密集词表达中,将这样的词表达应用到细粒度隐式篇章关系分类器。实验结果表明,在细粒度隐式篇章关系识别任务中,该方法的分类准确率达到49.79%,比未考虑篇章关系方向性的方法有较大程度的提高。

定向凝固镍基高温合金的组织结构与中温蠕变行为

通过蠕变性能测试、组织形貌观察,研究了定向凝固镍基高温合金热处理后组织形貌及其在760℃、700 MPa条件下蠕变不同时间的损伤机制。结果表明,合金热处理后,枝晶间和枝晶干区域的γ′相尺寸差异较大,粗大的γ′相和细小的γ′相分别存在于枝晶间和枝晶干区域。在760℃、700 MPa条件下合金蠕变断裂后立方γ′相并不形成筏状组织,并且越接近断口区域的γ′相扭曲越剧烈,这是由于在蠕变过程中试样断口区域发生了较大程度颈缩所致。蠕变后期,合金中裂纹首先在晶界和未完全消除的共晶组织处萌生与扩展,其中,沿与应力轴成45°的晶界承受较大剪切应力,因此发生蠕变损伤几率较大。