基于加权Voronoi多边形的山区农村居民点优化布局———以重庆市崇龛镇与石龙镇为例

中国的城市化进程伴随着农村人口向城市大量转移,使得乡村普遍面临人口流失、耕地撂荒及居民点闲置等问题,严重限制农村地区的经济发展,影响基础设施与公共服务设施的配置效率。优化农村居民点布局,实现资源的集约节约利用是国家新型城镇化规划的重要内容。文章以重庆市潼南县崇龛镇与巴南区石龙镇为例,探讨西南地区农村居民点空间布局优化的科学方法。首先,结合西南地区特有的自然人文条件,运用GIS空间分析技术与景观格局指数分析居民点分布特征;然后,构建包括限制性评价与适宜性评价两个阶段的西南地区居民点综合评价体系;基于对未来乡村发展趋势的判断,依据公平与效率原则,将现有居民点划分为发展型、保留型及迁并型等3类;在此基础上,运用加权Voronoi图确定重点发展型居民点的增长极引力范围,明确迁并型居民点与保留型居民点的发展方向,最终确定农村居民点布局的优化方案。经过优化,崇龛镇基于效率原则确定出222个重点发展型居民点,节约农村居民点用地0.813km2;石龙镇基于公平原则整理出416个重点发展型居民点,节约农村居民点用地0.301km2。研究能为2个示范镇农村居民点的规划优化提供科学依据,也为西南地区开展新型城镇化规划提供参考。     

石台县土壤硒资源分布特征及其利用

[目的]为实现对石台县土壤天然富硒资源的合理利用,促进石台县经济发展。[方法]文章通过实地调查与资料分析的方法,研究了石台县土壤硒资源空间分布的特点和土壤富硒资源利用途径。[结果]石台县土壤硒均值为0.5556mg/kg,达到富硒水平,石台县富硒地区占全县的28.73%,中硒地区占全县面积的67.62%,富硒地区主要分布在仙寓镇、七都镇、大演乡、丁香镇、仁里镇。石台县土壤硒含量主要与成土母岩、土壤质地、成土过程、土壤有机质和人类活动等影响因素有关。[结论]石台县土壤硒资源利用可以通过发展富硒茶、富硒米、富硒养生旅游、生态富硒高山蔬菜和瓜果、富硒中药材、富硒黑猪肉和富硒牛肉等富硒产业,富硒茶区域应设置在仙寓、七都、大演、矶滩、横渡5个乡镇,富硒米种植区域应设置在台县东部的七都镇和南部的仙寓镇,富硒养生旅游可以设置在横渡镇、仙寓镇、大演乡、丁香镇、小河镇,生态富硒蔬菜和瓜果应集中分布于石台县横渡、仁里、矶滩、七井等地,富硒养殖业可以分布在石台县西部的小河镇。     

Do regional house prices converge or diverge in China?

This paper aims to test whether the regional house prices are convergent or divergent in China using a monthly panel data set of China’s 70 large and medium-sized cities from July 2005 to December 2010. This issue is closely related to understanding the efficiency of the country-level housing policies made by China’s central government. The test results suggest that the regional house prices in China are generally divergent, and thereby the country-level policies may be inefficient since they do not explicitly take the strong heterogeneity of China’s regional housing markets into consideration. As a consequence, it may be better for China’s central government to further decentralize and devolve its governance toward the housing market to the local governments.     

Stuck in the Middle: Off-Farm Employment and Caregiving Among Middle-Aged Rural Chinese

ABSTRACT

Using the China Health and Retirement Longitudinal Study (CHARLS) 2011–12 baseline data, this contribution explores to what extent taking care of grandchildren and frail parents influences rural middle-aged Chinese adults’ off-farm employment. The findings show that, conditional on socioeconomic and demographic characteristics, taking care of grandchildren has a negative effect on rural middle-aged men's and women's off-farm job participation and hours worked. Caregiving for parents does not have the same negative effects on off-farm employment and hours worked. Furthermore, the study finds that annual earnings are also negatively affected by caregiving responsibilities, especially for women and men taking care of grandchildren.     

2×150MW CFB矸石发电机组运行

神华准能矸石发电公司两台东锅的480t/h CFB锅炉,配有2台南京的150MW汽轮机和两台南京的150MW 发电机.神华准能矸石发电公司自投产以来,从"星期机组"到现在连续安全经济运行,已近4年的时间.这期间经过公司上下的共同努力,以科学发展观和科技强企的工作指导思想,对设备系统进行技术改造,并且掌握了许多先进的运行...     

Pains and gains of environmental management system certification for the sustainable development of manufacturing companies: Heterogeneous effects of industry peer learning

Environmental sustainability is a growing global concern. Environmental management systems (EMS) could be an effective strategic tool to help firms deal with their sustainable development. However, whether EMS certification pays off financially and how it takes effect can be debated. Thus far, these questions remain largely under‐researched. In particular, the effects of EMS certification on financial performance are inconclusive, and the reasons explaining the effects are underdeveloped. This study aims to enrich the current research by exploring the mediating and moderating roles from the perspective of cost‐efficiency trade‐offs to reveal how EMS certification affects financial performance. Applying a PROCESS procedure analysis and causal mediation analysis to a sample of 1,751 Chinese listed manufacturing firms from 2008 to 2016, this study shows that the effect of EMS certification on firms' financial performance is insignificant because their operating costs burden increases while their marketing efficiency and managerial efficiency improve. For the first time, this study demonstrates the moderating role of industry peer learning, as the mediating effects decrease with the growth of industry peer learning.     

均衡性转移支付、公共支出结构与经济高质量发展

本文首先从理论层面系统阐述均衡性转移支付、公共支出结构与经济增长质量三者之间的多重作用机制。其次立足“五大发展理念”构建综合指标体系对经济增长质量展开测度，本文发现我国地方经济增长质量虽然在整体上呈缓慢上升态势，但其绝对水平相对偏低，且具有较为明显的地区异质性。最后本文通过构建动态面板联立方程模型与采取三阶段最小二乘法进行实证考察，结果表明：地方政府公共支出结构与经济增长质量显著正相关，但均衡性转移支付与经济增长质量的正相关关系并不显著。标准化回归结果显示均衡性转移支付能够通过优化公共支出结构对地方经济增长质量产生间接提升效应。     

基于声誉效应的工程监理激励机制模型研究

为了提高工程监理工作积极性,基于Holmstrom-Milgrom模型,引入声誉效应,建立声誉效应和显性激励机制相结合的动态委托代理激励模型。分析声誉效应发挥激励机制作用条件,并与未考虑声誉效应的委托代理模型进行比较。结果表明:声誉效应在满足一定的条件下,引入声誉激励机制能够增加业主的期望收益,并且能提高监理的努力水平。最后,通过数值仿真模拟验证引入声誉效应的合理性。     

国企利润分配制度改革与资本积累

依据鲍尔斯等学者对"剩余产品"的相关论述,本文将国企利润分配制度改革分为"利润控制主体改革"和"利润使用方式改革",按照这两个维度,立足于《资本论》中的理论与方法,建立了马克思主义理论框架,对国企利润分配制度改革作出了新的阶段划分,并解释了新中国成立以来国有工业企业的长期资本积累历程。本文的基本结论是,"利润控制主体改革"和"利润使用方式改革"均影响资本积累。当前,深化国有资本经营预算改革面临的真正挑战是预算支出结构改革将导致公平与效率的权衡,在民生支出提高的情况下需要保证国有资本经营预算的相对独立性,切实提高国有资本经营生产性支出效率。     

基于GIS的皖江流域耕地地力评价研究

[目的]为了整体掌握皖江流域耕地地力水平、特征和土壤肥力状况等,充分利用耕地资源,提升皖江流域的耕地质量。[方法]文章基于农业部耕地资源管理信息系统软件,分别构建了皖江流域平原区和皖江流域山地丘陵区的评价指标体系,并通过现在较为成熟的特尔菲法、层次分析法、模糊数学评价等方法相结合,开展皖江流域耕地地力评价。[结果]皖江流域平原区耕地划分为9个等级, 1～9等地耕地面积所占比例分别为8.7%,18.4%,22.5%,22.7%,13.5%,17.2%,2.8%,2.9%和1.3%,其中2等地、3等地以及4等地分布区域较广,所占面积较大;皖江流域山地丘陵区耕地划分为9个等级, 1～9等地耕地面积所占比例分别为2.2%,8.6%,14.2%,26.0%,21.3%,10.6%,9.0%,5.0%和3.2%,该区域主要有3等地、4等地、5等地分布。[结论]该评价结果对皖江流域耕地资源的科学管理和可持续利用以及农业现代化发展具有非常重要的意义。