Large biases exist in real-time ENSO prediction, which can be attributed to uncertainties in initial conditions and model parameters. Previously, a 4D variational （4D-Vat） data assimilation system was developed for ...Large biases exist in real-time ENSO prediction, which can be attributed to uncertainties in initial conditions and model parameters. Previously, a 4D variational （4D-Vat） data assimilation system was developed for an intermediate coupled model （ICM） and used to improve ENSO modeling through optimized initial conditions. In this paper, this system is further applied to optimize model parameters. In the ICM used, one important process for ENSO is related to the anomalous temperature of subsurface water entrained into the mixed layer （Te）, which is empirically and explicitly related to sea level （SL） variation. The strength of the thermocline effect on SST （referred to simply as ＂the thermocline effect＂） is represented by an introduced parameter, （l＇Te. A numerical procedure is developed to optimize this model parameter through the 4D-Var assimilation of SST data in a twin experiment context with an idealized setting. Experiments having their initial condition optimized only, and having their initial condition plus this additional model parameter optimized, are compared. It is shown that ENSO evolution can be more effectively recovered by including the additional optimization of this parameter in ENSO modeling. The demonstrated feasibility of optimizing model parameters and initial conditions together through the 4D-Var method provides a modeling platform for ENSO studies. Further applications of the 4D-Vat data assimilation system implemented in the ICM are also discussed.展开更多
Four-dimensional variational(4D-VAR) data assimilation method is a perfect data assimilation solution in theory, but the computational issue is quite difficult in operational implementation.The incremental 4D-VAR assi...Four-dimensional variational(4D-VAR) data assimilation method is a perfect data assimilation solution in theory, but the computational issue is quite difficult in operational implementation.The incremental 4D-VAR assimilation scheme is set up in order to reduce the computational cost. It is shown that the accuracy of the observations, the length of the assimilation window and the choice of the first guess have an important influence on the assimilation outcome through the contrast experiment. Compared with the standard 4D-VAR assimilation scheme, the incremental 4D-VAR assimilation scheme shows its advantage in the computation speed through an assimilation experiment.展开更多
4D技术的发展和应用给建设项目带来了巨大的效益,但目前用于4D模拟的3D模型一般在施工前创建,4D模拟的应用局限于施工前的计划阶段。为将4D模拟的应用扩展至项目施工阶段,对4D模拟的3D模型进行研究,着重对比分析施工模型和实时施工模型...4D技术的发展和应用给建设项目带来了巨大的效益,但目前用于4D模拟的3D模型一般在施工前创建,4D模拟的应用局限于施工前的计划阶段。为将4D模拟的应用扩展至项目施工阶段,对4D模拟的3D模型进行研究,着重对比分析施工模型和实时施工模型,研究BIM(Building Information Modeling,建筑信息模型)模型的自动创建技术。研究发现,自动化创建的BIM实时施工模型可以动态的跟踪项目进展情况,能提高模型的准确性和减少建模工作量。提出基于BIM实时施工模型的4D模拟,是一个动态的4D模拟过程,可作为项目施工全过程的动态控制的有效工具,能进一步提高建设项目的效率和效益。展开更多
文摘为探讨经典名方散偏汤对慢性偏头痛的作用机制,该研究采用4D-DIA蛋白质组学技术分析其对慢性偏头痛模型大鼠的干预影响,并对关键差异蛋白进行实验验证。首先将SD雄性大鼠随机分组,反复注射硝酸甘油制备慢性偏头痛模型。连续灌胃7 d后,采用大鼠痛苦面容量表(RGS)评估药效。取三叉神经节进行4D-DIA相对定量蛋白质组学检测,筛选各组差异蛋白,结合多个数据库进行基因本体论(Gene Ontology,GO)功能和京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)通路富集分析;使用STRING数据库及Cytoscape软件进行蛋白-蛋白互作(PPI)网络分析,并对关键差异表达蛋白TRPV1进行蛋白免疫印迹法(Western blot)检测。结果显示,空白组与模型组间有517个差异表达蛋白,模型组与散偏汤中剂量组间有221个差异表达蛋白。GO功能和KEGG通路富集分析显示,差异表达蛋白主要与炎症反应、伤害性感受刺激、甘油三酯代谢、免疫调节等相关,主要集中在炎症相关TRP通路、AMPK信号通路、PI3K-Akt信号通路、TGF-β信号通路等。PPI网络显示,IGF、TOP2A、APOA1、CDK1、TTN、RYR1、CSRP3等靶蛋白具有较高的度值(degree)。Western blot结果显示,与模型组比较,散偏汤中、高剂量组TRPV1表达水平差异有统计学意义(P<0.05)。综上,散偏汤可能通过调节TRP、AMPK、PI3K-Akt等炎症相关通路治疗慢性偏头痛,其对TRPV1蛋白的调节发挥了重要作用,并对伤害性刺激感受、脂代谢和免疫反应等具有潜在的调节作用。
基金supported by the National Natural Science Foundation of China (Grant Nos. 41705082, 41475101, 41690122(41690120))a Chinese Academy of Sciences Strategic Priority Project-the Western Pacific Ocean System (Grant Nos. XDA11010105 and XDA11020306)+1 种基金the National Programme on Global Change and Air–Sea Interaction (Grant Nos. GASI-IPOVAI06 and GASI-IPOVAI-01-01)the China Postdoctoral Science Foundation, and a Qingdao Postdoctoral Application Research Project
文摘Large biases exist in real-time ENSO prediction, which can be attributed to uncertainties in initial conditions and model parameters. Previously, a 4D variational （4D-Vat） data assimilation system was developed for an intermediate coupled model （ICM） and used to improve ENSO modeling through optimized initial conditions. In this paper, this system is further applied to optimize model parameters. In the ICM used, one important process for ENSO is related to the anomalous temperature of subsurface water entrained into the mixed layer （Te）, which is empirically and explicitly related to sea level （SL） variation. The strength of the thermocline effect on SST （referred to simply as ＂the thermocline effect＂） is represented by an introduced parameter, （l＇Te. A numerical procedure is developed to optimize this model parameter through the 4D-Var assimilation of SST data in a twin experiment context with an idealized setting. Experiments having their initial condition optimized only, and having their initial condition plus this additional model parameter optimized, are compared. It is shown that ENSO evolution can be more effectively recovered by including the additional optimization of this parameter in ENSO modeling. The demonstrated feasibility of optimizing model parameters and initial conditions together through the 4D-Var method provides a modeling platform for ENSO studies. Further applications of the 4D-Vat data assimilation system implemented in the ICM are also discussed.
基金the National Basic Research Program of China under Natural contract Nos 2007CB816001 and 2006CB400603Natinal Natural Science Foundation of China under contract Nos 40346027 and 40676008the China"908"-Project under Grant No.908-02-01-03 and 908-IC-I-13
文摘Four-dimensional variational(4D-VAR) data assimilation method is a perfect data assimilation solution in theory, but the computational issue is quite difficult in operational implementation.The incremental 4D-VAR assimilation scheme is set up in order to reduce the computational cost. It is shown that the accuracy of the observations, the length of the assimilation window and the choice of the first guess have an important influence on the assimilation outcome through the contrast experiment. Compared with the standard 4D-VAR assimilation scheme, the incremental 4D-VAR assimilation scheme shows its advantage in the computation speed through an assimilation experiment.
文摘4D技术的发展和应用给建设项目带来了巨大的效益,但目前用于4D模拟的3D模型一般在施工前创建,4D模拟的应用局限于施工前的计划阶段。为将4D模拟的应用扩展至项目施工阶段,对4D模拟的3D模型进行研究,着重对比分析施工模型和实时施工模型,研究BIM(Building Information Modeling,建筑信息模型)模型的自动创建技术。研究发现,自动化创建的BIM实时施工模型可以动态的跟踪项目进展情况,能提高模型的准确性和减少建模工作量。提出基于BIM实时施工模型的4D模拟,是一个动态的4D模拟过程,可作为项目施工全过程的动态控制的有效工具,能进一步提高建设项目的效率和效益。
