Engineering Research Express最新文献_第7页

Identification of nonlinear system model and inverse model based on conditional invertible neural network 基于条件可逆神经网络的非线性系统模型和逆模型识别

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad6f6e

Tian Chen, Xingwu Zhang, Chenxi Wang, Xuedan Feng, Jiaqiao Lv, Jiangtao Deng, Shangqin You, Xuefeng Chen

{"title":"Identification of nonlinear system model and inverse model based on conditional invertible neural network","authors":"Tian Chen, Xingwu Zhang, Chenxi Wang, Xuedan Feng, Jiaqiao Lv, Jiangtao Deng, Shangqin You, Xuefeng Chen","doi":"10.1088/2631-8695/ad6f6e","DOIUrl":"https://doi.org/10.1088/2631-8695/ad6f6e","url":null,"abstract":"In applications such as adaptive inverse control, internal model control, and active noise control, the identification accuracy of the system model and the inverse model directly affects the performance. However, it is not easy to identify inverse models for nonlinear systems. Moreover, existing methods require two identification calculations to obtain the system model and the inverse model. Therefore, an identification method of nonlinear system model and inverse model based on conditional invertible neural network (cINN) is proposed. The invertible structure of cINN enables simultaneous approximation of complex nonlinear functions and simultaneous acquisition of the corresponding inverse functions. Consequently, both the nonlinear system model and the inverse model can be identified concurrently through cINN. Moreover, the identification performance of the cINN-based method is validated and applied to disturbance cancellation in a classical nonlinear simulation system. Finally, the inverse model of the actuator is identified by cINN, and the inverse model is applied to the nonlinear compensation of the actuator.","PeriodicalId":11753,"journal":{"name":"Engineering Research Express","volume":"30 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation on the effects of deposition strategy on the mechanical characteristics and microstructure of austenitic stainless steel 308LSi manufactured via wire arc additive manufacturing 研究沉积策略对线弧快速成型技术制造的奥氏体不锈钢 308LSi 的机械特性和微观结构的影响

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad6eee

Mohd Hairizal Osman, Mohd Rizal Alkahari, Lailatul Harina Paijan, Nur Ayuni Ashyira Mohamad Yusri

{"title":"Investigation on the effects of deposition strategy on the mechanical characteristics and microstructure of austenitic stainless steel 308LSi manufactured via wire arc additive manufacturing","authors":"Mohd Hairizal Osman, Mohd Rizal Alkahari, Lailatul Harina Paijan, Nur Ayuni Ashyira Mohamad Yusri","doi":"10.1088/2631-8695/ad6eee","DOIUrl":"https://doi.org/10.1088/2631-8695/ad6eee","url":null,"abstract":"This study examines the impact of deposition strategy on ASS 308LSi thin-walled structure manufactured via the Wire Arc Additive Manufacturing (WAAM) technique on the microstructural characteristics, tensile strength, microhardness, Charpy impact testing, and fracture morphology of the WAAM 308LSi. The analysis of the microstructure reveals that the deposition strategy promotes transitioning from columnar to equiaxed fine grain structure. The tensile strength results show that specimens with a 45° deposition strategy exhibit lower anisotropy and higher tensile properties compared to those with a 0° deposition strategy, with improvements of 33.1% in the transverse direction and 26.7% in the longitudinal deposition directions, respectively. The microhardness in WAAM SS308LSi demonstrates variations in the bottom, middle, and top regions, with the highest average value observed at a 45° deposition strategy (213.3 ± 6.5 HV, 201.1 ± 10.7 HV, and 191.5 ± 5.2 HV) as well. The impact testing results indicate that the highest absorbed energy occurs at a 45° deposition strategy, with 75 ± 4.2 J and 74 ± 4.0 J for the transverse and longitudinal directions, respectively. The fractures observed during testing exhibit ductile characteristics, with the presence of dimples and particles. This study demonstrates the significant potential of the 45° deposition strategy with the implementation of double-sided substrate deposition, resulting in a refined microstructure, nearly isotropic behavior, and excellent mechanical performance.","PeriodicalId":11753,"journal":{"name":"Engineering Research Express","volume":"51 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulation of synaptic properties of ferroelectric memory capacitors and neural network applications 铁电记忆电容器的突触特性模拟与神经网络应用

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad708e

Shikai Liu, Xingyu Li, Yingfang Zhu, Yujie Wu, Qin Jiang, Yang Zhan, Minghua Tang, Shaoan Yan

引用次数: 0

Adaptive super-twisted sliding mode trajectory tracking control for quadrotor UAV with prescribed performance based on finite-time disturbance observer 基于有限时间扰动观测器的具有规定性能的四旋翼无人机自适应超扭曲滑模轨迹跟踪控制

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad70f3

Hongji Liang, Junli Li, Yuanyao Zhang

{"title":"Adaptive super-twisted sliding mode trajectory tracking control for quadrotor UAV with prescribed performance based on finite-time disturbance observer","authors":"Hongji Liang, Junli Li, Yuanyao Zhang","doi":"10.1088/2631-8695/ad70f3","DOIUrl":"https://doi.org/10.1088/2631-8695/ad70f3","url":null,"abstract":"This study proposes a finite-time disturbed observer-based prescribed performance adaptive super-twisted sliding mode trajectory tracking control scheme for quadrotor UAV. Based on the super-twisted sliding mode algorithm, adaptive control, finite-time theory, and prescribed performance control, this scheme aims to achieve stable tracking of a quadrotor UAV along a defined trajectory. This is achieved even when faced with challenges such as modeling uncertainty, external uncertainty, and complex interference environments. Firstly, the coupling between the channels and the disturbance effects are unified as the aggregate disturbance. To address the issue of the adverse impact of aggregate disturbance on system performance, a new finite-time disturbance observer is developed to estimate the overall disturbance. The observer can effectively eliminate the negative effects of the aggregate disturbance without considering the disturbed boundary conditions during the design process. Secondly, the disturbance estimation information and the adaptive super-twisted algorithm are used to construct the adaptive super-twisted sliding mode controllers for the position and attitude loops, respectively. Then, a prescribed performance control is designed to predefined the time for the position loop to effectively suppress the deleterious effects of interference. This ensures that the position system can quickly meet the prescribed tracking requirements. Finally, the stability of the designed trajectory tracking control system is demonstrated using the Lyapunov theorem. Numerical simulation results verify the effectiveness and superiority of the proposed controller.","PeriodicalId":11753,"journal":{"name":"Engineering Research Express","volume":"10 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of machining parameters on average surface roughness during computer numerical controlled dry milling of high strength AISI 420 martensitic stainless steel 计算机数控干铣高强度 AISI 420 马氏体不锈钢时加工参数对平均表面粗糙度的影响

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad7195

Pramod George, Philip Selvaraj D, D S Ebenezer Jacob Dhas, Pradeep George

引用次数: 0

Magnetostrictive assisted free and forced vibration response of layered functionally graded circular plate with effect of prestress 具有预应力效应的分层功能分级圆板的磁致伸缩辅助自由振动和受迫振动响应

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad6eec

Mukund A Patil, Ravikiran Kadoli

引用次数: 0

A short-term wind speed prediction method based on the IDBO-BPNN 基于 IDBO-BPNN 的短期风速预测方法

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad7199

Lingzhi Wang, Cheng Li, Chenyang Li, Ling Zhao

{"title":"A short-term wind speed prediction method based on the IDBO-BPNN","authors":"Lingzhi Wang, Cheng Li, Chenyang Li, Ling Zhao","doi":"10.1088/2631-8695/ad7199","DOIUrl":"https://doi.org/10.1088/2631-8695/ad7199","url":null,"abstract":"Wind energy is known for its uncertainty and volatility, necessitating accurate wind speed prediction for stable wind farm operations. To enhance wind speed prediction accuracy, this study proposes a BP neural network (BPNN) short-term wind speed prediction model based on the Improved Dung Beetle Optimization (IDBO) algorithm. Addressing the issue of local optimization and reduced accuracy in the BPNN optimized by the Dung Beetle Optimization (DBO) algorithm, the circle chaotic mapping is utilized for population initialization to achieve a more uniform initial distribution. The improved sine-cosine algorithm, triangle wandering strategy, and adaptive weight coefficient are then employed to optimize dung beetle positions, balancing global exploration and local development capabilities and improving the algorithm’s search performance. Finally, the improved DBO algorithm optimizes the weights and thresholds of the BPNN, and the IDBO-BPNN prediction model was constructed. Simulation experiments were conducted based on wind speed data from a wind farm in Ohio, USA. The IDBO-BPNN model was compared with other prediction models, and error evaluation indexes were introduced to evaluate the experimental results. The findings demonstrate that the suggested model yields the most accurate predictions and achieves the optimal error evaluation indexes. MAE, MSE, RMSE, NSE and R<sup>2</sup> of dataset 1 are 0.42247, 0.28775, 0.53642, 88.8785%, 89.161%, those of dataset 2 are 0.28283, 0.14952, 0.38668, 85.7383%, 86.577%, and those of dataset 3 are 0.45406, 0.39268, 0.62664, 84.3859%, 84.931%. In particular, compared with BPNN model, the five evaluation indexes of the IDBO-BPNN model promoted by 41.53%, 57.38%, 34.71%, 24.91%, and 11.44%, respectively in dataset 3. Therefore, that the proposed IDBO-BPNN model exhibits higher accuracy in short-term wind speed prediction, indicating its feasibility and superiority in the realm of wind energy.","PeriodicalId":11753,"journal":{"name":"Engineering Research Express","volume":"23 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of surface remelting on the characteristics of IN718 components fabricated using laser powder directed energy deposition 表面重熔对使用激光粉末定向能沉积技术制造的 IN718 部件特性的影响

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad7196

Raja S Thanumoorthy, Satyajeet Vijay Jadhav, R Oyyaravelu, Srikanth Bontha, Balan A S S

{"title":"Effect of surface remelting on the characteristics of IN718 components fabricated using laser powder directed energy deposition","authors":"Raja S Thanumoorthy, Satyajeet Vijay Jadhav, R Oyyaravelu, Srikanth Bontha, Balan A S S","doi":"10.1088/2631-8695/ad7196","DOIUrl":"https://doi.org/10.1088/2631-8695/ad7196","url":null,"abstract":"Laser Powder Directed Energy Deposition (LP-DED) fabricated components exhibit poor surface finish, necessitating additional post-processing steps prior to their practical application. Enhancing the surface quality of additively manufactured IN718 specimens through conventional post-processing methods is particularly challenging, given the material’s poor machinability and the complexity of the fabricated components. The current study is centered on comprehending the impact of Laser Surface Remelting (LSR) on the surface properties of Laser Powder Directed Energy Deposited (LP-DED) IN718 material. To gain insights into how remelting influences surface characteristics, remelting was carried out using various sets of parameters. The remelted zone exhibited a refined grain structure, leading to increased hardness. Moreover, significant reductions in surface roughness and residual stress were observed in the remelted samples. Regression analysis indicated that laser power played a pivotal role, with positive impact on surface finish and depth of influence but a negative impact on residual stress and hardness. Therefore, considering all the comparison metrics, remelting using laser power of 150 W and a scan speed of 1140 mm min<sup>−1</sup> were found to yield optimal surface conditions.","PeriodicalId":11753,"journal":{"name":"Engineering Research Express","volume":"10 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessing performance variability in a dual-fuel diesel engine using diesel and biogas: an experimental study across different compression ratios 评估使用柴油和沼气的双燃料柴油发动机的性能变化：不同压缩比的实验研究

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad710b

Sanjay D Mali, Pinkesh R Shah, Divyang R Shah

{"title":"Assessing performance variability in a dual-fuel diesel engine using diesel and biogas: an experimental study across different compression ratios","authors":"Sanjay D Mali, Pinkesh R Shah, Divyang R Shah","doi":"10.1088/2631-8695/ad710b","DOIUrl":"https://doi.org/10.1088/2631-8695/ad710b","url":null,"abstract":"The increasing concerns about energy security and environmental sustainability have intensified the search for alternative fuels. This study investigates the performance and emission characteristics of a dual-fuel diesel engine utilizing purified biogas and diesel across various compression ratios. A single-cylinder, direct-injection, water-cooled, variable compression ratio diesel engine was adapted to operate in dual-fuel mode, running experiments at compression ratios of 12, 14, 16, 18, and 20 with a constant injection timing of 23° before top dead center under different load conditions. The study reveals a peak brake thermal efficiency of 33.25% at a compression ratio of 20, demonstrating the potential of biogas as a viable alternative fuel. Notably, while carbon monoxide and hydrocarbon emissions decreased with higher compression ratios, nitrogen oxide emissions increased, highlighting a trade-off in emission characteristics. This work contributes to the understanding of biogas utilization in diesel engines, offering insights into optimizing engine performance and emissions through compression ratio adjustments. The findings can inform future developments in sustainable energy solutions.","PeriodicalId":11753,"journal":{"name":"Engineering Research Express","volume":"24-25 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental and numerical study on the performance index of mixing for low aspect ratio serpentine microchannels 低长径比蛇形微通道混合性能指标的实验和数值研究

IF 1.7

Engineering Research Express Pub Date : 2024-08-29 DOI: 10.1088/2631-8695/ad7198

Pooria Pirdavari, Farzad Pourfattah, Huy Tran, Lian-Ping Wang, Ziwen He, Min Y Pack

{"title":"Experimental and numerical study on the performance index of mixing for low aspect ratio serpentine microchannels","authors":"Pooria Pirdavari, Farzad Pourfattah, Huy Tran, Lian-Ping Wang, Ziwen He, Min Y Pack","doi":"10.1088/2631-8695/ad7198","DOIUrl":"https://doi.org/10.1088/2631-8695/ad7198","url":null,"abstract":"In this work, the effect of a range of Dean numbers (De) varying from 0.01–70 on low aspect ratio (AR = 0.05–0.2) serpentine microfluidic devices was studied experimentally and numerically. It was observed that the AR, the number of circular bumps, and the angular positions of bumps transverse to the flow have a significant influence on the pressure drop and flow features (i.e., the position and shape of flow separation zones). Mixing was exclusively driven by diffusive mechanisms at low De values and at high De values, it was primarily induced by Dean vortices. The lowest mixing index (MI) was observed for De = 1 in all channel types, highlighting the transition region between the diffusion and Dean vortices-dominant mixing regimes. The MI was generally increased by increasing the AR of the channels. However, at high De, Dean vortices became strong enough to induce rapid mixing that was largely independent of the AR and bump placement. A dimensional performance index (PI) was defined as a function of the MI and the pressure drop per unit length. Distinct flow patterns arising from various positioning of bumps resulted in significant variations in the MI and PI values, with different dependencies on De. This underscored the importance of bump positioning based on the operational De range to optimize the mixing performance. Despite minor deviations between the designed and fabricated channels, the use of 3D-printed molds proved effective even at scales close to the resolution of the printer, resulting in mixing patterns consistent with the designed channels. These findings provide valuable insights into optimizing serpentine microchannels for efficient mixing while considering the trade-offs between enhanced mixing and increased pressure drop.","PeriodicalId":11753,"journal":{"name":"Engineering Research Express","volume":"68 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0