Decomposing regional business change at plant level in Italy: A novel spatial shift‐share approach

In this paper, spatial shift‐share decomposition is analysed when applied to Italian data on regional business change at plant level, over the period 2004–2009. A new type of spatial decomposition, which looks more effectively at neighbourhood influence, is introduced here. Notable results emerge from the empirical investigation. First, it can be seen that the spatial level of aggregation greatly affects results. Second, evidence of neighbourhood advantage in the Southern NUTS 3 regions is found, together with opposite results for the Central‐Northern NUTS 3 regions. Finally, evidence of positive industrial mix effects is only found in Central‐Northern Italy.     

Substitution bias and the construction of a spatial cost of living index*

We estimate the spatial substitution bias based on the difference between a price index (PI) and the true cost of living (COL). This bias is computed at three geographical scales, using several fixed baskets and across different expenditures quartiles. Our results show a significant substitution bias for small geographical units. The choice of the base basket is also relevant for the bias estimation. Finally, the spatial substitution bias is larger for upper side of the expenditure distribution due to the heterogeneity in the consumption basket. This exercise shows that the spatial dimension affects the construction of a price index and that the approach of fixed baskets should be carefully considered in the estimation of spatial price differentials.     

如何提高新药研发的成功率：化合物的物理化学性质的优化及其对类药性质的影响

近年来,为提高新药研发的成功率,通过对实验药物的物理化学性质进行统计分析,并和成功药物进行比较对照,试图找出化合物的物理化学性质与它们的类药性质的关系,从而可以指导新药的设计,加快新药研发的成功率和研发速度.     

R290分体式空调器中制冷剂分布与安全性

采用实验研究的方法,针对R290分体式空调器的结构特点,将分体式空调器分成6个单独的部件,分别对不同充灌量条件下的1P和1.5P R290分体式空调器各个部件的制冷剂分布规律进行研究。实验结果表明开机状态下虽然制冷剂在冷凝器中的分布最多,但整个低压侧的制冷剂量占整个系统充灌量的50%—60%,但在关机后1.5小时,低压侧的制冷剂量占整个系统充灌量的85%—92%。     

R134a水平微细管内流动沸腾换热的实验研究

本文对R134a在水平微细管内的流动沸腾进行了实验研究。实验测试段选用了内径为1 mm、2 mm、3 mm共3种不同的水平光滑不锈钢管,实验的饱和温度为5~30℃,热流密度为2~70 k W/m2,流量范围为200~1500 kg/(m2·s)。实验结果表明:相同条件下,干涸前2 mm管较3 mm管换热系数平均增幅为11.6%,1 mm管较2 mm管换热增幅为26.3%,1 mm管径换热系数比3 mm管径平均增大40.8%。随着管径的减小,换热系数在更低的干度开始减小,质量流速和强制对流蒸发作用对换热系数的影响变小,热流密度的影响依然显著;塞状流和弹状流区域减小,泡状流和环状流区域增大。     

Fab-Union: A Collective Online to Offline Robotic Design Platform

Official architectural education in China remains very traditional and has yet to engage with the digital age. To counter this, Shanghai-based Fab-Union was set up in 2014 to establish a cross-disciplinary community – now over 10,000 strong – that is driving the emergence of digital crafts in the country. Here, its founder Philip Yuan and lead designer Hao Meng describe Fab-Union's online design platform, its offline collective design space, and its robotic factory that functions as an open research facility and fabrication workshop.     

激光修补技术在修复薄膜图形缺陷上的应用——薄膜图形缺陷激光修补机

阐述了应用激光修补技术在玻璃基板上去除金属及其化合物薄膜和在玻璃基板上沉积金属薄膜的图形缺陷修补原理与方法;简述了影响薄膜图形缺陷修补质量与效率的关键技术;简单介绍了薄膜图形缺陷激光修补机的系统构成及其技术与性能指标.     

柔性薄膜收发组件技术研究

采用有源相控阵技术的薄膜合成孔径雷达因其全天候、大范围、高精度的探测能力,受到各国广泛重视。柔性薄膜T/ R 组件,由于其重量轻、厚度薄、可弯曲的特性,可以满足天基预警雷达柔性薄膜天线的需要。柔性 薄膜收发组件作为薄膜合成孔径雷达的核心部件,成为薄膜合成孔径雷达(SAR)的关键。文中对柔性薄膜T/ R 组件的接收和发射电路、弯曲特性进行了仿真分析,并对该T/ R 组件样机进行测试验证,获得了工作频段为L 波段,接收增益大于24dB,噪声系数小于2dB,发射功率大于1W,弯曲对带内的损耗影响小于0. 1dB,对带内的相位影响小于2°的结果,其在噪声和接收性能上具有先进性,并对工程应用具有一定的实际参考意义。     

网络入侵检测系统中的漂移检测

目前基于机器学习的入侵检测系统大都建立在入侵数据始终保持统计平稳的假设之上,无法应对攻击者有意改变数据特性或新型攻击方式的出现,而导致的检测率下降的状况.对于上述问题,即攻击漂移,提出了加权Rényi距离的检测方法.在KDD Cup99数据集上的实验证明,Rényi距离可以有效地增强检测效果;在检测到漂移后,通过重新训练模型可以使得对攻击的识别率显著提高.