劳动力转移对城乡居民收入差距的非线性影响研究

借鉴已有相关研究成果,将劳动力转移、农业技术水平与城乡居民收入差距联系起来思考,可以具体地考察劳动力转移对城乡居民收入差距的影响.文章以农业技术水平作为门槛变量,选取2009—2019年中国31个省份的面板数据,利用泰尔指数测定城乡收入差距,以劳动力转移作为核心解释变量构建面板门槛模型,实证得出劳动力转移对城乡居民收入差距的非线性影响.研究发现:劳动力转移可以缩小城乡居民收入差距,且该影响具有单一门槛效应.在农业技术水平较低时,劳动力转移对城乡居民收入差距收敛效应较小;当农业技术水平越过门槛值达到较高水平后,劳动力转移对缩小城乡居民收入差距的效果几乎增加了一倍.此后,通过替换解释变量泰尔指数为城乡人均可支配收入比、替换核心解释变量农业技术水平为农业生产效率重新建立面板门槛模型,发现上述结论仍然成立,其检验结果具有较强的稳健性.文章将农业技术进步、劳动力转移、城乡居民收入差距这三个重要变量纳入同一模型框架中,在加深劳动力流动影响城乡居民收入差距这一视角的研究的同时,对缩小城乡居民收入差距政策的制定提供了重要的参考意义.     

Measuring and Achieving Equity in Multiperiod Emergency Material Allocation

Emergency material allocation is an important part of postdisaster emergency logistics that is significant for improving rescue effectiveness and reducing disaster losses. However, the traditional single‐period allocation model often causes local surpluses or shortages and high cost, and prevents the system from achieving an equitable or optimal multiperiod allocation. To achieve equitable allocation of emergency materials in the case of serious shortages relative to the demand by victims, this article introduces a multiperiod model for allocation of emergency materials to multiple affected locations (using an exponential utility function to reflect the disutility loss due to material shortfalls), and illustrates the relationship between equity of allocations and the cost of emergency response. Finally, numerical examples are presented to demonstrate both the feasibility and the usefulness of the proposed model for achieving multiperiod equitable allocation of emergency material among multiple disaster locations. The results indicate that the introduction of a nonlinear utility function to reflect the disutility of large shortfalls can make the material allocation fairer, and minimize large losses due to shortfalls. We found that achieving equity has a significant but not unreasonable impact on emergency costs. We also illustrate that using differing utility functions for different types of materials adds an important dimension of flexibility.     

Trends in the Race and Ethnicity of Eminent Americans

During the last several decades, the ethnic and racial composition of the American elite has changed to include some ethnic minorities and women. This study examines changes in the composition of one segment of the American elite: those who have obtained eminence in their occupations. Lieberson and Carter's study of the ethnic composition of eminent Americans, using Who's Who in America, is replicated with data from the 1990s (Lieberson and Carter, 1979, American Sociological Review 44:347–366). In addition, comparisons between blacks listed in Who's Who in America and blacks listed only in Who's Who among Black Americans are made. During the 20 years since Lieberson and Carter's study, Jews have made remarkable gains in eminent membership, while the rate of black representation has increased only moderately. Women are a small percentage of the eminent regardless of ethnicity, although black women are better represented than their counterparts in white ethnic groups.     

陶渊明的诗化人格

作家的人格是其作品风格的内在因素 ,往往决定着其作品的风格。我们在研究作品风格的时候 ,不能不关注作家的人格。只有对作家的人格进行全面深入的审视 ,才能更准确地理解和把握其作品的风格。探讨陶渊明的人格魅力及其特征 ,是深入研究陶渊明作品风格的至关重要的途径。从陶渊明的作品中 ,从他的言行中 ,我们可以领悟到他的情趣和胸襟 ,领悟到一种具体的人格。陶渊明自然率真平和旷达的个性特征构筑了他的诗化人格 ,即未经世俗异化的高尚贞洁的人格。这种人格的内在思想根源是自然化迁的宇宙观和委运自然的人生观。这种人格的外在表现形式是他任真自得和固穷守节的行为方式。他的作品中常见的酒与菊、孤松、孤云与归鸟等艺术形象组成了陶渊明诗化人格的象征系列     

脊波导宽频带电磁参数测试技术

针对高损耗介质材料电磁参数的宽频带测试问题,提出了利用脊波导进行测试的新方法,建立了电磁参数测试系统,并采用TRL技术进行了系统校准。该方法仅用3个波段的脊波导即可覆盖2.0～18.0GHz宽频带范围内的电磁参数测试,具有频带宽、体积小、测试精确度高等优点。     

论创新思维的基础

创新是人类的本质特征 ,在人类创新的实践中 ,创新思维具有基础性和先导性的作用 ,是理论创新、科技创新、体制创新的基础和前提。创新思维是唯物辩证法的基本原理与规律在思维过程中的具体运用和体现 ,是多种思维要素相互协调作用的结果 ,它有着坚实的物质基础、心理基础和方法论基础     

多媒体技术与素质教育

多媒体技术有利于开发人的潜能,提高教学质量,培养学生的广泛兴趣,有利于加强德育教育.素质教育需要多媒体技术,需要掌握多媒体技术的教师.造就一支具有创新意识、创新精神、创新能力的高素质教师队伍,是全面落实素质教育的根本保证.     

与时俱进、创新理论是党的建设的基础——学习江泽民同志《论党的建设》

理论建设是党的建设的首要问题。与时俱进、创新理论是马克思主义基本原理的必然要求,是保持党的先进性的客观需要,是党的建设的永恒主题。     

我国就业制度的演变及其对妇女发展的影响

文章着重研究不同的就业制度对妇女发展的深刻影响 ,阐述就业制度的选择与男女平等观念实现的关系 ,以期能为当前就业政策的制定提供一些理论思考     

建立高效的高校物流体系

将经济领域的物流引入高校,提出了高校物流体系概念;介绍了高校物流的组成要素及物流目标。为了增加高校在市场环境中的适应性及竞争能力,首先应提高物流系统中的管理水平,从整合、优化、预测的角度制定适应新形势下的物流战略。