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论计算机仿真理论中制模方法的特点 被引量:1
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作者 曹伟 姜斌 《自然辩证法研究》 CSSCI 北大核心 1998年第6期22-25,65,共5页
本文分析了计算机仿真理论中制模方法的若干特点,如实际系统的辨识与观测;基本模型的非形式描述,集总模型的简化规则与有效性判据;形式模型的分类与“系统规范”描述;仿真模型的必要条件;程序模型中程序正确性问题等。
关键词 计算机仿真理论 仿真理论 制模方法
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脑缺血的动物模型和制模方法 被引量:1
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作者 赵云辉 《国际医药卫生导报》 2001年第10C期114-115,共2页
建立可靠、稳定、经济的脑缺血动物模型,是研究缺血性脑血管疾病及其治疗的基础,而大脑中动脉阻塞性脑梗塞在临床脑梗塞中占60%,故其动物模型极为重要.笔者介绍几种常用的脑缺血。
关键词 大脑中动脉 脑缺血 动物模型 制模方法
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精密铸造制模新方法
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作者 王海才 肖根楠 熊武 《江西工业大学学报》 1992年第4期127-131,共5页
本文主要介绍根据熔模铸造原理而创造的一种制造大、中型冲压成形模具的新方法,着重阐述了在大模样材料选择、提高模壳的强度与表面质量以及制件的尺寸精度控制等三个关键性问题上的独特见解和创造性的应用。论文还介绍了精密铸造制模... 本文主要介绍根据熔模铸造原理而创造的一种制造大、中型冲压成形模具的新方法,着重阐述了在大模样材料选择、提高模壳的强度与表面质量以及制件的尺寸精度控制等三个关键性问题上的独特见解和创造性的应用。论文还介绍了精密铸造制模法的主要优点和应用实例,并展望了这种新工艺的应用前景。 展开更多
关键词 制模方法 模样材料 模壳强度 铸件尺寸精度 精密铸造
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构建各期大鼠压疮模型方法的实验研究 被引量:6
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作者 张亚楠 李贤 +3 位作者 严德云 赵志红 郑美洁 高文娟 《护理研究(上旬版)》 2017年第11期3945-3948,共4页
[目的]建立大鼠四期两个阶段的大鼠压疮模型,为动物压疮相关研究提供参考依据。[方法]将64只大鼠按随机数字表随机分为8组,即空白组、对照组、一期组、二期组、可疑深部组织损伤组、三期组、不可分期组、四期组,每组8只,通过在臀肌下埋... [目的]建立大鼠四期两个阶段的大鼠压疮模型,为动物压疮相关研究提供参考依据。[方法]将64只大鼠按随机数字表随机分为8组,即空白组、对照组、一期组、二期组、可疑深部组织损伤组、三期组、不可分期组、四期组,每组8只,通过在臀肌下埋置铁片,在体外放置圆形磁铁从而对肌肉和皮肤产生压力,造成局部组织缺血,每次加压2h后将磁铁取下血流灌注0.5h,如此循环,每天大鼠连续进行5个循环后将磁铁取下,第2天重复以上步骤。[结果]通过不同的循环数成功复制大鼠四期两个阶段的压疮模型。[结论]臀肌下埋置铁片体外加压磁铁,通过不同的加压循环数可以复制出不同期的大鼠压疮模型,模型稳定,可重复复制,此研究结果可应用于压疮预防与治疗的研究。 展开更多
关键词 各期 压疮 压疮模型 组织学 病理学 制模方法 大鼠 实验研究
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两种微倾黏土场地离心模型制备方法适用对比研究 被引量:1
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作者 刘荟达 王永志 《地震工程与工程振动》 CSCD 北大核心 2020年第3期130-138,共9页
侧移是强震灾害中场地地基破坏的典型形式之一,而倾斜场地是侧移发生的一个重要条件。倾斜场地的制备是开展离心地震模型试验的基础而重要环节,针对两种微倾灵敏或软黏土场地的制备方法,通过常重力和60 g离心加速度下的T-bar试验,探讨... 侧移是强震灾害中场地地基破坏的典型形式之一,而倾斜场地是侧移发生的一个重要条件。倾斜场地的制备是开展离心地震模型试验的基础而重要环节,针对两种微倾灵敏或软黏土场地的制备方法,通过常重力和60 g离心加速度下的T-bar试验,探讨抗剪强度的分布规律与空间均匀性,对比了两方法的适用性。试验结果表明:表面斜割法获得模型的抗剪强度随深度变化较均匀,常重力和离心加速度下与理论状态较好吻合;双箱变换-倾楔法在拆换的剪切箱内抗剪强度随深度发生了显著折减,且在顶部呈现回弯现象,常重力和离心加速度下与理论状态偏差较大,折减系数约为0.31;相比而言,前者更适于制备微倾灵敏黏土场地模型。研究方法和结论,对动力离心模型试验制备方法选取和进一步开展黏土场地侧移离心模型试验研究,提供了重要借鉴和理论支撑。 展开更多
关键词 场地侧移 动力离心模型 制模方法 抗剪强度 适用性
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纸浆模塑模具材料的性能及其应用 被引量:5
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作者 曲晓晴 黄俊彦 高娟娟 《中国造纸》 CAS 北大核心 2010年第12期66-70,共5页
针对制作纸浆模塑模具用材料的基本要求,综述了各种制模材料的特性及其对纸浆模塑生产的影响,介绍了用各种材料制作纸浆模塑模具的方法及其应用,为纸浆模塑模具的制作和生产提供参考。
关键词 纸浆模塑 模具材料 材料特性 制模方法
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纸浆模塑模具的制作材料及其性能
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作者 高娟娟 黄俊彦 曲晓晴 《包装学报》 2010年第4期10-13,共4页
针对制作纸浆模塑模具用材料的基本要求,介绍了各种制模材料的特性、规格及其对纸浆模塑生产的影响,综述了各种材料制作纸模模具的方法及其应用。
关键词 纸浆模塑 模具材料 材料特性 制模方法
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A molding method to fabricate the waveguide multilayer card 被引量:1
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作者 ZHOU Wang-ren LIANG Zhong-cheng GU Min-fen 《Optoelectronics Letters》 EI 2008年第2期153-154,共2页
Waveguide multilayer optical card (WMOC) is a new kind of three-dimensional storage device. A method of fabricating the WMOC using the molding technique is introduced in this paper. The fabrication of WMOC mainly incl... Waveguide multilayer optical card (WMOC) is a new kind of three-dimensional storage device. A method of fabricating the WMOC using the molding technique is introduced in this paper. The fabrication of WMOC mainly includes data writing with hot embossing method and multilayer bonding with PDMS material. The structure of the WMOC is consisted with Polycarbonate (PC) as the core layer material and Polydimethylsiloxane (PDMS) as cladding layer. The experimental results demonstrate that the molding fabrication method is feasible and effective. 展开更多
关键词 波导 多层卡 制模方法 结构
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Framework-solvent interactional mechanism and effect of NMP/DMF on solvothermal synthesis of [Zn_4O(BDC)_3]_8 被引量:3
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作者 吴争平 王明雪 +4 位作者 周丽姣 尹周澜 谈进 张锦玲 陈启元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3722-3731,共10页
In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) o... In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF. 展开更多
关键词 solvothermal synthesis [Zn4O(BDC)3]8 N-METHYL-2-PYRROLIDONE interactional mechanism COSMO solvation model density functional method
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新专利技术
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《陶瓷》 CAS 2007年第8期61-61,共1页
基于CAD/CAE/RP技术的陶瓷坐便器的快速制模方法;抛光砖防污剂的制膜设备及方法;异型陶瓷成形模具;
关键词 专利技术 CAD/CAE 制模方法 RP技术 成形模具 坐便器 膜设备 防污剂
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专利信息
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作者 王元荪 《山东陶瓷》 CAS 2008年第5期48-48,共1页
抛光砖防污剂的制膜设备及方法;基于CAD/CAE/CAM的陶瓷坐便器快速制模方法;实木瓷砖;异型陶瓷成形模具;一种陶瓷离心压力注浆成形机;加固水泥结合力瓷砖。
关键词 专利信息 CAD/CAE/CAM 制模方法 成形模具 压力注浆 膜设备 防污剂 抛光砖
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Modeling of Energy Consumption and Effluent Quality Using Density Peaks-based Adaptive Fuzzy Neural Network 被引量:10
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作者 Junfei Qiao Hongbiao Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第5期968-976,共9页
Modeling of energy consumption(EC) and effluent quality(EQ) are very essential problems that need to be solved for the multiobjective optimal control in the wastewater treatment process(WWTP). To address this issue, a... Modeling of energy consumption(EC) and effluent quality(EQ) are very essential problems that need to be solved for the multiobjective optimal control in the wastewater treatment process(WWTP). To address this issue, a density peaks-based adaptive fuzzy neural network(DP-AFNN) is proposed in this study. To obtain suitable fuzzy rules, a DP-based clustering method is applied to fit the cluster centers to process nonlinearity.The parameters of the extracted fuzzy rules are fine-tuned based on the improved Levenberg-Marquardt algorithm during the training process. Furthermore, the analysis of convergence is performed to guarantee the successful application of the DPAFNN. Finally, the proposed DP-AFNN is utilized to develop the models of EC and EQ in the WWTP. The experimental results show that the proposed DP-AFNN can achieve fast convergence speed and high prediction accuracy in comparison with some existing methods. 展开更多
关键词 Density peaks clustering effluent quality (EQ) energy consumption (EC) fuzzy neural network improved Levenberg-Marquardt algorithm wastewater treatment process (WWTP).
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Adaptive control using interval Type-2 fuzzy logic for uncertain nonlinear systems 被引量:5
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作者 周海波 应浩 段吉安 《Journal of Central South University》 SCIE EI CAS 2011年第3期760-766,共7页
A new adaptive Type-2 (T2) fuzzy controller was developed and its potential performance advantage over adaptive Type-1 (T1) fuzzy control was also quantified in computer simulation. Base on the Lyapunov method, th... A new adaptive Type-2 (T2) fuzzy controller was developed and its potential performance advantage over adaptive Type-1 (T1) fuzzy control was also quantified in computer simulation. Base on the Lyapunov method, the adaptive laws with guaranteed system stability and convergence were developed. The controller updates its parameters online using the laws to control a system and tracks its output command trajectory. The simulation study involving the popular inverted pendulum control problem shows theoretically predicted system stability and good tracking performance. And the comparison simulation experiments subjected to white noige or step disturbance indicate that the T2 controller is better than the T1 controller by 0--18%, depending on the experiment condition and performance measure. 展开更多
关键词 Type-2 fuzzy systems adaptive fuzzy control nonlinear systems stability
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Study of Interval Type-2 Fuzzy Controller for the Twin-tank Water Level System 被引量:4
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作者 赵涛岩 李平 曹江涛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1102-1106,共5页
For dealing with large static error due to poor immunity of the traditional fuzzy control, a novel interval type-2 fuzzy control system is proposed. By extending the typical membership functions to interval type-2 mem... For dealing with large static error due to poor immunity of the traditional fuzzy control, a novel interval type-2 fuzzy control system is proposed. By extending the typical membership functions to interval type-2 membership functions, the proposed control system can efficiently reduce the uncertain disturbance from real environment without increasing the design complexity. The simulation results on the water tank level control system showed that the proposed method succeeded in better static and dynamic control with stronger robust performance than the traditional fuzzy control method. 展开更多
关键词 interval type-2 fuzzy set fuzzy control system twin-tank water level system
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Application of pH control to a tubular flow reactor 被引量:1
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作者 .Halil Vural Ayla Altinten +2 位作者 Hale Hapoglu Sebahat Erdogan Mustafa Alpbaz 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期154-161,共8页
Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the ... Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the present work, sodium hydroxide and acetic acid solutions were sent to the tubular flow reactor. The aim was to control p H at 7 in the nonlinear region. The p H control of a tubular flow reactor with high time delay and a highly nonlinear behavior in p H neutralization reaction was investigated experimentally in the face of the various load and set point changes. Firstly, efficiency of conventional Proportional-Integral-Derivative(PID) algorithm in the experiments was tested. Then self-tuning PID(STPID) control system was applied by using the ARMAX model. The model parameters were calculated from input–output data by using PRBS signal as disturbance and Bierman algorithm. Lastly, the experimental fuzzy control of p H based on fuzzy model was achieved to compare the success of fuzzy approach with the performance of other control cases studied. 展开更多
关键词 Tubular flow reactor p H control Self tuning PID control PID control Fuzzy control
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A Multiple Model Approach to Modeling Based on Fuzzy Support Vector Machines 被引量:2
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作者 冯瑞 张艳珠 +1 位作者 宋春林 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期137-141,共5页
A new multiple models(MM) approach was proposed to model complex industrial process by using Fuzzy Support Vector Machines(F -SVMs). By applying the proposed approach to a pH neutralization titration experiment, F -SV... A new multiple models(MM) approach was proposed to model complex industrial process by using Fuzzy Support Vector Machines(F -SVMs). By applying the proposed approach to a pH neutralization titration experiment, F -SVMs MM not only provides satisfactory approximation and generalization property, but also achieves superior performance to USOCPN multiple modeling method and single modeling method based on standard SVMs. 展开更多
关键词 fuzzy support vector machines(FSVMs) fuzzy support vector classifier(FSVC) fuzzy support vector regression(FSVR) multiple model MODELING
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Gastric cancer:Animal studies on the risk of hypoacidity and hypergastrinemia 被引量:5
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作者 Reidar Fossmark Gunnar Qvigstad Helge L Waldum 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第11期1646-1651,共6页
Gastric hypoacidity and hypergastrinaemia are seen in several conditions associated with an increased risk of gastric malignancy.Hypoacidity and hypergastrinaemia are closely related and their long-term effects are di... Gastric hypoacidity and hypergastrinaemia are seen in several conditions associated with an increased risk of gastric malignancy.Hypoacidity and hypergastrinaemia are closely related and their long-term effects are difficult to study separately in patients.Studies using animal models can provide valuable information about risk factors and mechanisms in gastric cancer development as the models allow a high degree of intervention when introducing or eliminating factors possibly affecting carcinogenesis.In this report,we briefly review findings from relevant animal studies on this topic.Animal models of gastric hypoacidity and hypergastrinaemia provide evidence hypergastrinaemia is a common causative factor in many otherwise diverse settings.In all species where sufficient hypoacidity and hypergastrinaemia have been induced,a proportion of the animals develop malignant lesions in the gastric oxyntic mucosa. 展开更多
关键词 Gash'in Gastric cancer Proton pump inhibitors Acid secretion Animal model
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Dynamic modelling of 2-DOF luffing mechanism with serial closed kinematic chains 被引量:2
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作者 ZHU Zhen-xin ZHU Jian-xin +1 位作者 KANG Hui-mei QIAN Huan-yun 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第1期168-178,共11页
Luffing mechanism is a key component of the construction machinery.This paper proposes a two degree of freedom(2-DOF)luffing mechanism,which has one more pair of driving cylinders than the single DOF luffing mechanism... Luffing mechanism is a key component of the construction machinery.This paper proposes a two degree of freedom(2-DOF)luffing mechanism,which has one more pair of driving cylinders than the single DOF luffing mechanism,to improve the performance of the machinery.To establish the dynamic model of the 2-DOF luffing mechanism,firstly,we develop a hierarchical method to deduce the Jacobian matrix and Hessian matrix for obtaining the kinematics equations.Subsequently,we divide the luffing mechanism into six bodies considering actuators,and deduce the kinetic equations of each body by the Newton-Euler method.Based on the dynamic model,we simulate the luffing process.Finally,a prototype is built on a pile driver to validate the model.Simulations and experiments show that the dynamic model can reflect the dynamic properties of the proposed luffing mechanism.And the control strategy that the front cylinders retract first shows better mechanical behavior than the other two control strategies.This research provides a reference for the design and application of 2-DOF luffing mechanism on construction machinery.The modeling approach can also be applied to similar mechanism with serial closed kinematic chains,which allows to calculate the dynamic parameters easily and exactly. 展开更多
关键词 luffing mechanism dynamic model hierarchical method control strategy PROTOTYPE
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A New Tuning Method for Two-Degree-of-Freedom Internal Model Control under Parametric Uncertainty 被引量:10
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作者 Juwari Purwo sutikno Badhrulhisham Abdul aziz +1 位作者 Chin Sim yee Rosbi Mamat 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期1030-1037,共8页
Internal model control (IMC) yields very good performance for set point tracking, but gives sluggish response for disturbance rejection problem. A two-degree-of-freedom IMC (2DOF-IMC) has been developed to overcom... Internal model control (IMC) yields very good performance for set point tracking, but gives sluggish response for disturbance rejection problem. A two-degree-of-freedom IMC (2DOF-IMC) has been developed to overcome the weakness. However, the setting of parameter becomes a complicated matter if there is an uncertainty model. The present study proposes a new tuning method for the controller. The proposed tuning method consists of three steps. Firstly, the worst case of the model uncertainty is determined. Secondly, the parameter of set point con- troller using maximum peak (Mp) criteria is specified, and finally, the parameter of the disturbance rejection con- troller using gain margin (GM) criteria is obtained. The proposed method is denoted as Mp-GM tuning method. The effectiveness of Mp-GM tuning method has evaluated and compared with IMC-controller tuning program (IMCTUNE) as bench mark. The evaluation and comparison have been done through the simulation on a number of first order plus dead time (FOPDT) and higher order processes. The FOPDT process tested includes processes with controllability ratio in the range 0.7 to 2.5. The higher processes include second order with underdarnped and third order with nonminimum phase processes. Although the two of higher order processes are considered as difficult processes, the proposed Mp-GM tuning method are able to obtain the good controller parameter even under process uncertainties. 展开更多
关键词 tuning 2DOF-IMC model uncertainty dead time process Mp-GM tuning IMCTUNE
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Research on Dynamic Model's Building of Active Magnetic Suspension Systems 被引量:4
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作者 施建 颜国正 +1 位作者 李黎川 王坤东 《Journal of Donghua University(English Edition)》 EI CAS 2006年第3期131-135,共5页
An experimental method is introduced in this paper to build the dynamics of AMSS (the active magnetic suspension system), which doesn’t depend on system’s physical parameters. The rotor can be reliably suspended und... An experimental method is introduced in this paper to build the dynamics of AMSS (the active magnetic suspension system), which doesn’t depend on system’s physical parameters. The rotor can be reliably suspended under the unit feedback control system designed with the primary dynamic model obtained. Online identification in frequency domain is processed to give the precise model. Comparisons show that the experimental method is much closer to the precise model than the theoretic method based on magnetic circuit law. So this experimental method is a good choice to build the primary dynamic model of AMSS. 展开更多
关键词 active magnetic suspension feedback control dynamic model building experimental method
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