通胀目标制与汇率目标制不能共存吗

基于汇率传递的风险溢价渠道，本文将我国利率调控通胀、外汇储备对冲干预汇率纳入新凯恩斯政策模型，构建双目标双工具政策分析框架，比较泰勒规则与双目标双工具规则下通胀目标与汇率目标共存的经济机制与效应。本文模拟显示：（1）双目标双工具政策框架下通胀目标与汇率目标能够共存，此时通过影响汇率风险溢价来盯住汇率不影响通胀；而单工具政策下两目标无法共存，此时降低国内资产的收益率盯住汇率会刺激居民的消费行为引起通胀。（2）国际资本冲击下，双目标双工具政策在固定汇率的同时能保证经济稳定；而当贸易条件恶化时，选择完全浮动汇率制度最优。央行政策损失分析进一步验证了以上结论。（3）随着金融市场化改革深入，外汇储备稳定汇率的有效性将下降，冲销成本会大幅提升。资本账户开放下，双目标双工具政策仍是央行抵御外部资本冲击的首选政策；但是汇率市场化后，通胀目标制与双目标双工具政策效果基本无差异。本文结论的启示是：面对国际资本，需必要的汇率管制；但是面对贸易冲击，可适度提升汇率弹性来减少冲击对产出和通胀的影响。     

就业结构调整对水库移民土地流转的影响研究*——以南水北调中线工程移民为例

[目的]为促进水库移民的生计恢复及转型,探寻就业结构和土地流转间的交互机制,分析两者间耦合作用对当前移民安置模式及政策的影响。[方法]文章从移民就业结构变迁出发,通过超边际理论构建了安置区移民土地的流转机制模型,推演了从业决策对土地流转行为的影响路径,并运用南水北调农业安置移民数据进行实证检验。[结果]大面积转出土地是移民搬迁后土地处置的主要行为,移民中土地转入户有所增加,但土地集中度却有所减少。移民非农就业较搬迁前有明显上升,并有向当地兼业转移的趋势,但与土地流转间并不互为因果,农村社保还难以弱化其对土地养老的依赖。劳动力数量、非农就业时间、非农收入占比、土地政策等对移民土地流转行为和规模均有显著影响,而外出就业前景和地租水平在促进土地流转行为的同时,却不一定能增加土地流转面积。[结论]移民外迁中可以采用无土安置代替农业安置,推动移民土地流转的关键在于技能培训、政策保障和地租补贴,简单的就业推荐和土地权属划分的作用有限。而对于移民中的农业大户,则需在满足土地转入面积的基础上,保障其在安置区的各项土地权益。     

Why has China’s vertical specialization declined?

Vertical specialization (VS) is quantified by the VS share, which measures the average import content per dollar of exports. A characteristic of China’s export trade is its strong dependence on assembly and processing activities. To take proper account of this, China’s VS shares should explicitly distinguish processing export production from other production. We estimate China’s annual VS shares from 2000 to 2012—the latest year for which a special input–output table is available that makes such an explicit distinction. We find that VS shares increased from 2000 to 2004 and subsequently started to decrease. To explore why it has declined, we introduce a new structural decomposition approach. We find that the decrease of the VS share appears to have been driven mainly by the substitution of imported intermediates by domestic products. This occurred in particular in the production of exports, which implies an upgrading of China’s position in global value chains.     

Crowdsourcing-based semantic relation recognition for natural language questions over RDF data

ABSTRACT

Natural language query systems over RDF data need to rely on the semantic relations in query. First, we propose the new crowdsourcing model that used to produce semantic relations dataset. The model not only inherits completeness of the iterative model and accuracy of the parallel model, but also saves human resources. Second, we mine the rules of semantic relation recognition from the correlations between dependency structures and semantic relations. Third, we propose an algorithm of semantic relation recognition for natural language query over RDF data, and experiments demonstrate that it can recognize more semantic relations than existing methods.     

微波加热对叶绿素水溶液的影响

本文通过对叶绿素水溶液进行微波加热,分析微波加热对叶绿素水溶液的温度、色度、叶绿素含量的影响。结果表明,微波加热处理的水溶液温度显著高于对照沸水浴,1~2 min时,1000 W功率下的水溶液温度显著高于200 W(P<0.05)。与沸水浴相比,微波加热显著降低了叶绿素水溶液的绿色程度,且高功率微波加热显著加剧了水溶液亮度的变化。200 W微波加热使水溶液中叶绿素a、b含量降低,但1000 W微波加热则提高了水溶液中叶绿素a、b含量。     

Training and organisational performance: A meta‐analysis of temporal,institutional and organisational context moderators

Drawing on systems theory, we conducted a moderated meta‐analysis of the training and organisational performance relationship using 119 primary studies. We examined the moderating effects of quality versus quantity of training, time, institutional and organisational context factors in the relationship between training and organisational performance. Our findings reveal that training is positively and directly related to organisational performance with no statistically significant difference between measures of training quality and quantity. We found that the relationship was stronger over time and that country performance orientation and country labour cost moderate the training and organisational performance relationship. We found no evidence for the moderating effects of the three organisational context moderators we examined (i.e. industry sector, organisational size and technology intensity). Finally, our results reveal that training type (i.e. general or firm‐specific) does not moderate the training and organisational performance relationship.     

京津冀城市群土地经济密度时空格局演变与驱动因素分析

[目的]研究2006—2016年京津冀城市群土地经济密度的时空格局演变特征及其驱动机制。[方法]以京津冀城市群153个县区为例,运用空间自相关分析、热点分析、地理探测器等研究方法,对土地经济密度的时空演变规律及其驱动因素进行探讨。[结果](1)2006—2016年京津冀城市群县区和地市的土地经济密度及其发展速度在空间上均呈"东高西低,南高北低"格局,但随时间变化区域差异逐渐缩小;(2)Moran′s I指数由0.013 9上升至0.065 3,表明在空间上存在空间集聚状态,且随时间不断优化,区域一体化趋势逐渐增强;(3)空间集聚特征明显,热点显著区集中于北京、天津等经济优势区,并向四周梯度扩散;(4)人均GDP、当年实际使用外资额、固定资产投资额等经济类因子对土地经济密度的解释力较大,且任意两因子交互后作用力优于单项因子作用力。[结论]可为京津冀城市群土地资源的合理利用和差别化调控提供参考。     

Potential Spatial Labor and Human Capital Mobility in China: Evidence from College Admissions Under the National College Entrance Examination System

Abstract:

Higher education in China plays an important role in promoting labor and human capital mobility. In this paper, I empirically address the issue of regional disparities, college admissions under the National College Entrance Examination (CEE) system, and potential interregional labor and human capital mobility in China. The results show that examinees from western provinces have a strong preference for coastal universities, compared with examinees from central provinces. College admissions in China then seem to have a stronger effect on potential labor and human capital movement from the western to the coastal regions than from the central to the coastal regions.     

一种改进的非凸秩最小化算法及其在矩阵恢复中的应用

在分析现有处理矩阵恢复问题的非凸秩最小化算法的基础上,提出了一种基于超松弛迭代的改进算法,并给出了松弛因子ω的确定准则。仿真实验表明:在惩罚参数选取较大的情形下,改进算法较原算法具有更快的收敛速度及更高的收敛精度,同时展示了基于非凸秩最小化算法的矩阵恢复技术在图像去噪中的应用。     

中国新能源汽车产业创新系统功能演化研究--兼论政府措施的作用

新能源汽车产业是中国重点发展的七大战略性新兴产业之一,剖析其创新系统的发展与完善过程,识别发展过程中的影响因素,并了解政府在这一演化过程中如何进行介入和引导,对新能源汽车以及其他新兴产业的发展具有重要的理论与实践价值。本文以创新系统功能理论为基础,构建了针对中国新能源汽车产业创新系统演化分析的功能框架,剖析了中国新能源汽车产业创新系统功能体系的发展与完善过程,同时讨论了政府措施在这一过程中的引导与支撑作用。研究发现,中国新能源汽车产业创新体系正处于快速完善阶段,知识获取、产业制度体系建设等功能已经成熟,而基础设施与支撑平台建设、产业链整合与升级以及正向外部性创造等功能仍有待于进一步完善。同时发现,这一过程中政府采取的各种措施与产业发展过程中遇到的阻碍因素密切相关,措施的类型与着力点也随着各种阻碍因素的出现不断变化,发挥了积极的引导作用。