A projected skill is adopted by use of the differential evolution (DE) algorithm to calculate a conditional nonlinear optimal perturbation (CNOP). The CNOP is the maximal value of a constrained optimization problem wi...A projected skill is adopted by use of the differential evolution (DE) algorithm to calculate a conditional nonlinear optimal perturbation (CNOP). The CNOP is the maximal value of a constrained optimization problem with a constraint condition, such as a ball constraint. The success of the DE algorithm lies in its ability to handle a non-differentiable and nonlinear cost function. In this study, the DE algorithm and the traditional optimization algorithms used to obtain the CNOPs are compared by analyzing a theoretical grassland ecosystem model and a dynamic global vegetation model. This study shows that the CNOPs generated by the DE algorithm are similar to those by the sequential quadratic programming (SQP) algorithm and the spectral projected gradients (SPG2) algorithm. If the cost function is non-differentiable, the CNOPs could also be caught with the DE algorithm. The numerical results suggest the DE algorithm can be employed to calculate the CNOP, especially when the cost function is non-differentiable.展开更多
为研究上海某石化工业区臭氧来源特征,采用在线监测系统对该工业区O_(3)及其前体物和气象参数展开了为期3个月(2020年6~8月)的同步连续观测.采用TCEQ(Texas Commission on Environmental Quality)区域背景臭氧估算法和主成分分析两种方...为研究上海某石化工业区臭氧来源特征,采用在线监测系统对该工业区O_(3)及其前体物和气象参数展开了为期3个月(2020年6~8月)的同步连续观测.采用TCEQ(Texas Commission on Environmental Quality)区域背景臭氧估算法和主成分分析两种方法研究工业区区域背景和本地生成O_(3)浓度贡献,并将两种方法进行对比分析.结果表明:(1)观测期间园区主导风向为东南风和东风,平均温度为27.12℃.ρ(VOCs-36)日均值为32.05~240.51μg·m^(-3),烷烃浓度占比最大;ρ(NOx)日均值为10.15~47.51μg·m^(-3);ρ(O_(3))为31.81~144.43μg·m^(-3).(2)TCEQ法得出的区域背景O_(3)浓度[ρR(O_(3))]为32.63~191.13μg·m^(-3),本地生成O_(3)浓度[ρL(O_(3))]为16.08~134.25μg·m^(-3),区域背景占比ω(TCEQ)为32.6%~87.7%.主成分分析计算得出的区域背景[ρPCA-R(O_(3))]为66.38~219.83μg·m^(-3);(3)TCEQ法计算得出的本地生成O_(3)浓度变化基本能够与该园区内臭氧生成潜势的变化对应,两种方法具有良好的吻合效果,经验证结果具有可靠性;(4)剔除由于站点浓度异常情况带来的计算误差,观测期间区域背景O_(3)占比基本处于75%~95%范围内.综上,园区内O_(3)浓度组成以区域输送为主,应重点关注工业区周边城市的O_(3)污染治理,落实长三角区域联防联控措施.展开更多
VAT Scheme Completed China has replaced all business tax with value-added tax（VAT）after extending the policy to cover the construction,real estate,finance and consumer services sectors on May 1.They were the last fo...VAT Scheme Completed China has replaced all business tax with value-added tax（VAT）after extending the policy to cover the construction,real estate,finance and consumer services sectors on May 1.They were the last four sectors still taxed based on their revenue.VAT refers to a tax levied on the difference between a commodity’s pre-tax price and its production cost.展开更多
基金provided by grants from the National Basic Research Program of China (Grant No. 2006CB400503)LASG Free Exploration Fund+1 种基金LASG State Key Laboratory Special Fundthe KZCX3-SW-230 of the Chinese Academy of Sciences
文摘A projected skill is adopted by use of the differential evolution (DE) algorithm to calculate a conditional nonlinear optimal perturbation (CNOP). The CNOP is the maximal value of a constrained optimization problem with a constraint condition, such as a ball constraint. The success of the DE algorithm lies in its ability to handle a non-differentiable and nonlinear cost function. In this study, the DE algorithm and the traditional optimization algorithms used to obtain the CNOPs are compared by analyzing a theoretical grassland ecosystem model and a dynamic global vegetation model. This study shows that the CNOPs generated by the DE algorithm are similar to those by the sequential quadratic programming (SQP) algorithm and the spectral projected gradients (SPG2) algorithm. If the cost function is non-differentiable, the CNOPs could also be caught with the DE algorithm. The numerical results suggest the DE algorithm can be employed to calculate the CNOP, especially when the cost function is non-differentiable.
文摘为研究上海某石化工业区臭氧来源特征,采用在线监测系统对该工业区O_(3)及其前体物和气象参数展开了为期3个月(2020年6~8月)的同步连续观测.采用TCEQ(Texas Commission on Environmental Quality)区域背景臭氧估算法和主成分分析两种方法研究工业区区域背景和本地生成O_(3)浓度贡献,并将两种方法进行对比分析.结果表明:(1)观测期间园区主导风向为东南风和东风,平均温度为27.12℃.ρ(VOCs-36)日均值为32.05~240.51μg·m^(-3),烷烃浓度占比最大;ρ(NOx)日均值为10.15~47.51μg·m^(-3);ρ(O_(3))为31.81~144.43μg·m^(-3).(2)TCEQ法得出的区域背景O_(3)浓度[ρR(O_(3))]为32.63~191.13μg·m^(-3),本地生成O_(3)浓度[ρL(O_(3))]为16.08~134.25μg·m^(-3),区域背景占比ω(TCEQ)为32.6%~87.7%.主成分分析计算得出的区域背景[ρPCA-R(O_(3))]为66.38~219.83μg·m^(-3);(3)TCEQ法计算得出的本地生成O_(3)浓度变化基本能够与该园区内臭氧生成潜势的变化对应,两种方法具有良好的吻合效果,经验证结果具有可靠性;(4)剔除由于站点浓度异常情况带来的计算误差,观测期间区域背景O_(3)占比基本处于75%~95%范围内.综上,园区内O_(3)浓度组成以区域输送为主,应重点关注工业区周边城市的O_(3)污染治理,落实长三角区域联防联控措施.
文摘臭氧(O_(3))作为地球大气中重要的微量成分,平均含量10~100 ppb,平流层集中了大部分O_(3),而对流层O_(3)含量仅占总量的10%左右。平流层O_(3)可降低太阳紫外线进入地球,保护人类及动植物。近地面污染物浓度及其扩散、反应、沉降等过程在很大程度上依赖于上层混合及垂直边界层的物理状况,如夜间残留层的O_(3)在次日可以被下沉运动带到地面,从而使地面的O_(3)浓度升高,甚至影响近地面的光化学污染进程。因此,利用差分吸收O_(3)激光雷达对阿拉善盟巴彦浩特环保局新楼站点附近O_(3)时空分布特征进行连续观测,研究了阿拉善盟巴彦浩特地区O_(3)日变化时空分布特征,分析了本地生成和区域传输两种类型的O_(3)污染来源。结果显示:巴彦浩特大气O_(3)监测时段日变化时空分布特征显著,一般在午后呈现典型的单峰特征;在O_(3)本地生成过程中,近地面O_(3)主要呈现高浓度,同时高度增大O_(3)浓度逐渐减小,高值O_(3)主要集中在1 km以下,1.5~2 km O_(3)浓度变化趋势平缓,并结合气象场分析了山谷风环流特征对O_(3)浓度的影响。
文摘VAT Scheme Completed China has replaced all business tax with value-added tax（VAT）after extending the policy to cover the construction,real estate,finance and consumer services sectors on May 1.They were the last four sectors still taxed based on their revenue.VAT refers to a tax levied on the difference between a commodity’s pre-tax price and its production cost.
