互联网贸易能否缩小收入差距?——双异质模型及来自中国的经验

互联网贸易作为影响社会经济的一种新兴贸易模式,其对居民收入差距的影响区别于传统贸易,且具有不确定性。系统分析互联网贸易对收入差距的综合影响效应可为我国缓解收入差距矛盾提供可资借鉴的解决方案。本文尝试构建双异质贸易理论分析框架,从数理模型的角度解释互联网贸易对收入差距的影响机制和影响效应,理论和实证研究表明互联网贸易能够缩小地区内收入差距和城乡收入差距,而互联网贸易规模的扩大和渗透能力的增强则是互联网贸易影响收入差距的关键变量。大力发展互联网贸易,同时完善既有收入分配调整政策是促进我国收入差距进一步缩小的有效途径。

互联网贸易发展与收入分配差距

互联网贸易作为数字经济背景下影响经济发展的重要模式,其诸多区别于传统贸易形式的新特点对居民收入分配差距产生不确定性影响。本文通过构建包含互联网贸易与劳动力要素在内的双异质理论模型,基于2000~2018年样本数据的实证检验结果,深入剖析互联网贸易发展对不同类型收入分配差距影响的内在机理。研究结果表明:互联网贸易发展不仅可以缩小地区收入差距,而且能够改善城乡收入差距状况。其中,互联网贸易规模的扩大与渗透能力的增强是互联网贸易发展改善居民收入分配差距的重要原因。

HBT's High Frequency Noise Modeling and Analysis

A T equivalent high frequency heterojunction bipolar transistor (HBT) noise model is reported.This model is derived from Hawkins noise model commonly used in Si BJT.The main modifications include the influence of the ideality factor,emitter resistance,intrinsic base collector capacitance,extrinsic base collector capacitance and other parasitic elements of HBT represented in equivalent circuit topology.In order to calculate accurate noise parameters from the equivalent circuit,the noise correlation matrix method is used to avoid any simplifications generated in circuit transformations and complex noise measurements.The analysis of the influence of the equivalent circuit elements on the minimum noise figure is reported,the results of analysis agree well with the physics explanations.By means of the formulae derived from device physics of HBT,the influence of device parameters on the minimum noise figure is also represented.