Pub Date : 2024-09-17DOI: 10.1088/1402-4896/ad78c6
Jaya Joshi, Rajeev, J F Gómez-Aguilar and J E Lavín-Delgado
This paper centers around a space-fractional mathematical model for a fluvio-deltaic sedimentation process which involves a space-fractional derivative (Caputo derivative) and time dependent variable sediment flux to investigates the movement of shoreline in a sedimentary ocean basin. This model is a specific case of a basic shoreline model and analogous to a Stefan problem. The numerical solution to the problem is acquired by employing a front-fixing explicit finite difference method. The consistency, stability and convergence of the numerical scheme are theoretically analyzed. The effects of variable sediment flux on the movement of shoreline position and the height of sediments are also assessed for different cases.
{"title":"A front-fixing numerical method for a fluvio-deltaic sedimentation process with thespace fractional derivative and variable sediment flux","authors":"Jaya Joshi, Rajeev, J F Gómez-Aguilar and J E Lavín-Delgado","doi":"10.1088/1402-4896/ad78c6","DOIUrl":"https://doi.org/10.1088/1402-4896/ad78c6","url":null,"abstract":"This paper centers around a space-fractional mathematical model for a fluvio-deltaic sedimentation process which involves a space-fractional derivative (Caputo derivative) and time dependent variable sediment flux to investigates the movement of shoreline in a sedimentary ocean basin. This model is a specific case of a basic shoreline model and analogous to a Stefan problem. The numerical solution to the problem is acquired by employing a front-fixing explicit finite difference method. The consistency, stability and convergence of the numerical scheme are theoretically analyzed. The effects of variable sediment flux on the movement of shoreline position and the height of sediments are also assessed for different cases.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1088/1402-4896/ad7409
Jiajun Xian, Teng Wang, Wei Zhang, Kunwei Chen, Nan Meng, Jiawen Sun, Dan Yang, Ming Liu, Jinlin Ye and Wei Wang
Epidemic transmission and the associated awareness diffusion are fundamentally interactive. There has been a burgeoning interest in exploring the coupled epidemic-awareness dynamic. However, current research predominantly focuses on self-protection behavior stimulated by awareness, paying less attention to self-isolation behavior. Given the constraints of government-mandated quarantine measures, spontaneous self-isolation actions assume greater significance in the long-term response to epidemics. In response, we propose a coupled awareness-epidemic spreading model with the consideration of self-isolation behavior and subsequently employ a Micro Markov Chain Approach to analyze the model. Extensive experiments show that self-isolation behavior can effectively raise the epidemic threshold and reduce the final outbreak scale. Notably, in multiplex networks with positive inter-layer correlation, the inhibitory effect is the greatest. Moreover, there exists a metacritical point, only when the awareness diffusion probability exceeds the critical value of this point, the epidemic threshold will increase with the increase of awareness diffusion probability. In addition, the growth of the average degree of the virtual-contact layer can reduce the value of this metacritical point. This research emphasizes the significant role of self-isolation behavior in curbing epidemic transmission, providing valuable perspectives for epidemic prevention through the interplay of awareness and epidemic spreading.
{"title":"Coupled awareness-epidemic spreading with the consideration of self-isolation behavior","authors":"Jiajun Xian, Teng Wang, Wei Zhang, Kunwei Chen, Nan Meng, Jiawen Sun, Dan Yang, Ming Liu, Jinlin Ye and Wei Wang","doi":"10.1088/1402-4896/ad7409","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7409","url":null,"abstract":"Epidemic transmission and the associated awareness diffusion are fundamentally interactive. There has been a burgeoning interest in exploring the coupled epidemic-awareness dynamic. However, current research predominantly focuses on self-protection behavior stimulated by awareness, paying less attention to self-isolation behavior. Given the constraints of government-mandated quarantine measures, spontaneous self-isolation actions assume greater significance in the long-term response to epidemics. In response, we propose a coupled awareness-epidemic spreading model with the consideration of self-isolation behavior and subsequently employ a Micro Markov Chain Approach to analyze the model. Extensive experiments show that self-isolation behavior can effectively raise the epidemic threshold and reduce the final outbreak scale. Notably, in multiplex networks with positive inter-layer correlation, the inhibitory effect is the greatest. Moreover, there exists a metacritical point, only when the awareness diffusion probability exceeds the critical value of this point, the epidemic threshold will increase with the increase of awareness diffusion probability. In addition, the growth of the average degree of the virtual-contact layer can reduce the value of this metacritical point. This research emphasizes the significant role of self-isolation behavior in curbing epidemic transmission, providing valuable perspectives for epidemic prevention through the interplay of awareness and epidemic spreading.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1088/1402-4896/ad7648
Bin Rong, Wei Zhao, Yi Liao, Yixiao Zhang, Yangyang Zhu, Wei Shi and Bin Wei
Organic field-effect transistors (OFETs) incorporating hybrid high-κ inorganic Al2O3 and polymer dielectrics, including polyvinyl alcohol (PVA), polystyrene (PS), or polymethyl methacrylate (PMMA), through solution-processing techniques were fabricated. The analyses revealed that the high surface energy and hydrophilicity property of Al2O3 and PVA, and the relatively hydrophobic property of PS surface, hindered the performance of corresponding OFETs. The Al2O3/PMMA-based OFET achieved the optimized performance, with a threshold voltage of −2.7 V, a hole carrier mobility of 0.056 cm2/Vs, and a current on/off ratio of 1.0 × 104 at a low operating voltage of −5 V. Through analyzing the characteristics of leakage current, capacitance, contact resistance, and trap density of OFETs, we found that the PMMA-engaged films possessed the optimized electrical properties. The introduction of PMMA eliminated the interfacial trapping, thereby lowering the threshold voltage and enhancing the performance of the device. The COMSOL Multiphysics simulation was conducted to confirm the physical mechanism. The strategy of utilizing Al2O3/PMMA hybrid dielectric could simultaneously ensure the low operating voltage and good performance of OFET, while guaranteeing the low leakage current by the thick PMMA.
{"title":"Low-voltage organic field-effect transistors by using solution-processable high-κ inorganic-polymer hybrid dielectrics","authors":"Bin Rong, Wei Zhao, Yi Liao, Yixiao Zhang, Yangyang Zhu, Wei Shi and Bin Wei","doi":"10.1088/1402-4896/ad7648","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7648","url":null,"abstract":"Organic field-effect transistors (OFETs) incorporating hybrid high-κ inorganic Al2O3 and polymer dielectrics, including polyvinyl alcohol (PVA), polystyrene (PS), or polymethyl methacrylate (PMMA), through solution-processing techniques were fabricated. The analyses revealed that the high surface energy and hydrophilicity property of Al2O3 and PVA, and the relatively hydrophobic property of PS surface, hindered the performance of corresponding OFETs. The Al2O3/PMMA-based OFET achieved the optimized performance, with a threshold voltage of −2.7 V, a hole carrier mobility of 0.056 cm2/Vs, and a current on/off ratio of 1.0 × 104 at a low operating voltage of −5 V. Through analyzing the characteristics of leakage current, capacitance, contact resistance, and trap density of OFETs, we found that the PMMA-engaged films possessed the optimized electrical properties. The introduction of PMMA eliminated the interfacial trapping, thereby lowering the threshold voltage and enhancing the performance of the device. The COMSOL Multiphysics simulation was conducted to confirm the physical mechanism. The strategy of utilizing Al2O3/PMMA hybrid dielectric could simultaneously ensure the low operating voltage and good performance of OFET, while guaranteeing the low leakage current by the thick PMMA.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1088/1402-4896/ad76ea
Shreyas Tiwari, Rajesh Saha and Tarun Varma
The basic building block of neural network is a device, which can mimic the neural behavior. The spiking neural network (SNN) is an efficient methodology in terms of power and area. Due to the excess energy consumption and larger area, various spintronic neural devices are unfit for neuron applications. In this article, we have implemented Ge source based Tunnel FET (TFET) for ultralow energy spike generation using TCAD simulator. It is seen that Ge source TFET has signature spiking frequency in THz range versus input voltage curve of an artificial biological neuron. The simulated device deploy the leaky integrate and fire (LIF) technique for generation of neurons. The simulation result highlights that the energy of device is 1.08 aJ/spike, which is several order less than existing neural based FET devices in literature.
{"title":"An energy efficient leaky integrate and fire neuron using Ge-source TFET for spiking neural network: simulation analysis","authors":"Shreyas Tiwari, Rajesh Saha and Tarun Varma","doi":"10.1088/1402-4896/ad76ea","DOIUrl":"https://doi.org/10.1088/1402-4896/ad76ea","url":null,"abstract":"The basic building block of neural network is a device, which can mimic the neural behavior. The spiking neural network (SNN) is an efficient methodology in terms of power and area. Due to the excess energy consumption and larger area, various spintronic neural devices are unfit for neuron applications. In this article, we have implemented Ge source based Tunnel FET (TFET) for ultralow energy spike generation using TCAD simulator. It is seen that Ge source TFET has signature spiking frequency in THz range versus input voltage curve of an artificial biological neuron. The simulated device deploy the leaky integrate and fire (LIF) technique for generation of neurons. The simulation result highlights that the energy of device is 1.08 aJ/spike, which is several order less than existing neural based FET devices in literature.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Surface blistering on tungsten under deuterium plasma exposure has been well known and investigated intensively in the last decade. However, the mechanism of the blistering is still unclear. There have been mainly two different models proposed: the gas driven model and lateral stress model. In this work, we designed an experiment to address this issue. Tungsten disc samples were prepared using twin-jet electro-polishing. The specimens were under deuterium plasma exposure to study the thickness effect on the surface blistering. The results showed that blistering was rarely observed on the surface around the inner edge of the central perforation with thickness of ∼100–500 nm. The blisters started to appear on the surface when the thickness was about 10 μm. Both the number and size of the blisters increased further on the outer surface with further increase in thickness. This trend was not obvious as the thickness increased up to above 180 μm. The diffusion depth of D in this work was calculated to be 8.5 μm. These results affirmed the lateral stress model as the surface blistering mechanism.
{"title":"Lateral stress induced blistering of tungsten exposed to deuterium plasma","authors":"Zhenyu Jiang, Tongjun Xia, Wenjia Han, Yongzhi Shi, Wenjie Zhang and Kaigui Zhu","doi":"10.1088/1402-4896/ad75ce","DOIUrl":"https://doi.org/10.1088/1402-4896/ad75ce","url":null,"abstract":"Surface blistering on tungsten under deuterium plasma exposure has been well known and investigated intensively in the last decade. However, the mechanism of the blistering is still unclear. There have been mainly two different models proposed: the gas driven model and lateral stress model. In this work, we designed an experiment to address this issue. Tungsten disc samples were prepared using twin-jet electro-polishing. The specimens were under deuterium plasma exposure to study the thickness effect on the surface blistering. The results showed that blistering was rarely observed on the surface around the inner edge of the central perforation with thickness of ∼100–500 nm. The blisters started to appear on the surface when the thickness was about 10 μm. Both the number and size of the blisters increased further on the outer surface with further increase in thickness. This trend was not obvious as the thickness increased up to above 180 μm. The diffusion depth of D in this work was calculated to be 8.5 μm. These results affirmed the lateral stress model as the surface blistering mechanism.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1088/1402-4896/ad77f8
Wenguang Yang, Wenhao Wang, Xiangyu Teng, Zezheng Qiao, Haibo Yu and Shuxiang Cai
The manipulation of micron-scale semicircular tubular structures has wide applications in micro-nano processing, device manufacturing, biomedicine, and micron sensing and measurement. Here, we propose a method to fabricate and manipulate semicircular tubular structures based on optically induced dielectrophoresis (ODEP). First, electric field intensity simulations are performed for polyethylene glycol diacrylate (PEGDA) semicircular tubular structures with different conductivities and of different heights. In addition, the polarization model based on slender rods reveals that the semicircular tubular structure is subject to a negative dielectrophoretic force and tends to move along the vertical direction of the central axis. Finally, according to the maximum movement speed of the semicircular tubular structure, the resistance and dielectrophoretic force it receives are characterized. This allows for the realization of the translation and rotation operations of semicircular tubular structures of different lengths, and the assembly of multiple structures into different shapes. This assembly method holds significant promise for applications in biomedicine and the manufacturing and processing of micro-nano devices.
{"title":"The electrodynamic analysis and manipulation of PEGDA semicircular tubular structures based on optically induced dielectrophoresis","authors":"Wenguang Yang, Wenhao Wang, Xiangyu Teng, Zezheng Qiao, Haibo Yu and Shuxiang Cai","doi":"10.1088/1402-4896/ad77f8","DOIUrl":"https://doi.org/10.1088/1402-4896/ad77f8","url":null,"abstract":"The manipulation of micron-scale semicircular tubular structures has wide applications in micro-nano processing, device manufacturing, biomedicine, and micron sensing and measurement. Here, we propose a method to fabricate and manipulate semicircular tubular structures based on optically induced dielectrophoresis (ODEP). First, electric field intensity simulations are performed for polyethylene glycol diacrylate (PEGDA) semicircular tubular structures with different conductivities and of different heights. In addition, the polarization model based on slender rods reveals that the semicircular tubular structure is subject to a negative dielectrophoretic force and tends to move along the vertical direction of the central axis. Finally, according to the maximum movement speed of the semicircular tubular structure, the resistance and dielectrophoretic force it receives are characterized. This allows for the realization of the translation and rotation operations of semicircular tubular structures of different lengths, and the assembly of multiple structures into different shapes. This assembly method holds significant promise for applications in biomedicine and the manufacturing and processing of micro-nano devices.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1088/1402-4896/ad7538
Jie Sun, Qiulan Zhao and Xinyue Li
We study the symmetric structures and dynamic analysis of a (2 + 1)-dimensional generalized Benny-Luke (GBL) equation based on the Lie symmetry method, the GBL equation is an important non-integrable model of water waves. Specifically, we construct multiple exact solutions of the GBL equation and obtain its nonlocally related systems. Firstly, the Lie point symmetries and conservation laws of the GBL equation are computed, and then we get the reduced ordinary differential equation from one of the conservation laws. Multiple methods, for example, the dynamical systems method, the power series method, the homogeneous balancing method and generalized variable separation method, are used to solve the ordinary differential equation and abundant exact solutions of the GBL equation are got. Finally, we extend these exact solutions by discrete symmetries, and give three-dimensional graphs of partial exact solutions. In addition, we construct the nonlocally related PDE systems, which contains the potential systems from the conservation laws and an inverse system from a Lie point symmetry of the GBL equation. These findings reveal the dynamical behavior behind the GBL equation and broaden the range of nonlinear water wave model solutions.
{"title":"Symmetric structures and dynamic analysis of a (2+1)-dimensional generalized Benny-Luke equation","authors":"Jie Sun, Qiulan Zhao and Xinyue Li","doi":"10.1088/1402-4896/ad7538","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7538","url":null,"abstract":"We study the symmetric structures and dynamic analysis of a (2 + 1)-dimensional generalized Benny-Luke (GBL) equation based on the Lie symmetry method, the GBL equation is an important non-integrable model of water waves. Specifically, we construct multiple exact solutions of the GBL equation and obtain its nonlocally related systems. Firstly, the Lie point symmetries and conservation laws of the GBL equation are computed, and then we get the reduced ordinary differential equation from one of the conservation laws. Multiple methods, for example, the dynamical systems method, the power series method, the homogeneous balancing method and generalized variable separation method, are used to solve the ordinary differential equation and abundant exact solutions of the GBL equation are got. Finally, we extend these exact solutions by discrete symmetries, and give three-dimensional graphs of partial exact solutions. In addition, we construct the nonlocally related PDE systems, which contains the potential systems from the conservation laws and an inverse system from a Lie point symmetry of the GBL equation. These findings reveal the dynamical behavior behind the GBL equation and broaden the range of nonlinear water wave model solutions.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1088/1402-4896/ad7706
Yudong Zhong, Xue Zeng, Junjian Hou, Ruolan Wang, Liangwen Wang, Dengfeng Zhao, Wenbin He and Yinan Zheng
Crack detection and identification is of great significance to the safety issues of engineering structures. In this paper, an intelligent crack identification scheme based on extended finite element and neural network surrogate model is proposed to realize the accurate identification of crack parameters. The method firstly employs extended finite element forward analysis to obtain the displacement data of measurement points on geometric models with different crack lengths, and inputs them as sample data to train the agent model, establishes a neural network-based inverse analysis model for crack identification, and automatically updates the threshold and weight of the neural network by using the Gray Wolf optimization algorithm to finally compute the globally optimal results. In the screening of the surrogate model, this paper verifies the advantages of the neural network surrogate model in data fitting and crack information extraction by comparing and analyzing the characteristics of neural network, support vector machine and other surrogate models, and optimizing the neural network surrogate model by adopting the Gray Wolf optimization algorithm. Finally, several numerical examples of different types of cracks are given to verify the validity of the proposed method, and the results show that the proposed method can accurately invert the geometric information of cracks.
{"title":"A crack identification scheme based on neural network surrogate model and XFEM","authors":"Yudong Zhong, Xue Zeng, Junjian Hou, Ruolan Wang, Liangwen Wang, Dengfeng Zhao, Wenbin He and Yinan Zheng","doi":"10.1088/1402-4896/ad7706","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7706","url":null,"abstract":"Crack detection and identification is of great significance to the safety issues of engineering structures. In this paper, an intelligent crack identification scheme based on extended finite element and neural network surrogate model is proposed to realize the accurate identification of crack parameters. The method firstly employs extended finite element forward analysis to obtain the displacement data of measurement points on geometric models with different crack lengths, and inputs them as sample data to train the agent model, establishes a neural network-based inverse analysis model for crack identification, and automatically updates the threshold and weight of the neural network by using the Gray Wolf optimization algorithm to finally compute the globally optimal results. In the screening of the surrogate model, this paper verifies the advantages of the neural network surrogate model in data fitting and crack information extraction by comparing and analyzing the characteristics of neural network, support vector machine and other surrogate models, and optimizing the neural network surrogate model by adopting the Gray Wolf optimization algorithm. Finally, several numerical examples of different types of cracks are given to verify the validity of the proposed method, and the results show that the proposed method can accurately invert the geometric information of cracks.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1088/1402-4896/ad7201
Zakir Hussain, Fazia and Muhammad Shoaib Anwar
This article presents Artificial Neural Networks (ANN) for convective heat transfer in a trapezoidal cavity subjected to corrugated heated rod inside it. The LevenbergMarquardt algorithm is utilized to optimize the Neural Networks. The trapezoidal cavity has low-temperature inclined walls and adiabatic upper and lower walls compared to the corrugated heated rod. Single-wall carbon (SWCNTs) nanomaterials are submerged in the base liquid water. The flow of SWCNTs-water is generated due to the temperature gradient in the cavity. The system of dimensional partial differential equations has been formulated for the physical setup under investigation. The dimensional system has been converted into a non-dimensional form using dimensionless variables. Finite element is used for the solutions. The dimensionless functions velocity, temperature, and heat transfer rates are studied against the Rayleigh number (Ra). The outcomes are presented in the form of isotherms, contours, tabular values, and graphs. The data for Artificial Neural Networks (ANN) has been generated by FEM against the Nusselt number. The ANN has been trained for a specific amplitude of the rod and predicted heat transfer against a larger amplitude. The results show good agreement for both training and testing data. The outcomes of analysis reveals that convection caused by temperature gradient is dominant for higher values of the Rayleigh number (Ra). Local Nusselt number has been discussed against different amplitudes, and predicted enhancement for the larger amplitude of the rod.
本文介绍了人工神经网络（ANN）用于梯形空腔内波纹加热棒的对流传热。采用 LevenbergMarquardt 算法对神经网络进行优化。与波纹加热棒相比，梯形空腔具有低温倾斜壁和绝热上下壁。单壁碳纳米材料（SWCNTs）被浸没在基础液态水中。由于空腔中的温度梯度，SWCNTs-水产生流动。针对所研究的物理装置，我们制定了维度偏微分方程系统。使用无量纲变量将量纲系统转换为非量纲形式。有限元用于求解。针对雷利数 (Ra) 对无量纲函数速度、温度和传热率进行了研究。研究结果以等温线、等值线、表格值和图表的形式呈现。人工神经网络（ANN）的数据是由 FEM 根据努塞尔特数生成的。已针对杆的特定振幅对人工神经网络进行了训练，并针对更大的振幅对传热进行了预测。结果显示，训练数据和测试数据的一致性都很好。分析结果表明，温度梯度引起的对流在雷利数（Ra）值较高时占主导地位。针对不同振幅对局部努塞尔特数进行了讨论，并预测了较大振幅杆的增强效果。
{"title":"Neural network approach to investigate heat transfer in SWCNTs nanofluid within trapezoidal cavity with varied corrugated rod amplitudes","authors":"Zakir Hussain, Fazia and Muhammad Shoaib Anwar","doi":"10.1088/1402-4896/ad7201","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7201","url":null,"abstract":"This article presents Artificial Neural Networks (ANN) for convective heat transfer in a trapezoidal cavity subjected to corrugated heated rod inside it. The LevenbergMarquardt algorithm is utilized to optimize the Neural Networks. The trapezoidal cavity has low-temperature inclined walls and adiabatic upper and lower walls compared to the corrugated heated rod. Single-wall carbon (SWCNTs) nanomaterials are submerged in the base liquid water. The flow of SWCNTs-water is generated due to the temperature gradient in the cavity. The system of dimensional partial differential equations has been formulated for the physical setup under investigation. The dimensional system has been converted into a non-dimensional form using dimensionless variables. Finite element is used for the solutions. The dimensionless functions velocity, temperature, and heat transfer rates are studied against the Rayleigh number (Ra). The outcomes are presented in the form of isotherms, contours, tabular values, and graphs. The data for Artificial Neural Networks (ANN) has been generated by FEM against the Nusselt number. The ANN has been trained for a specific amplitude of the rod and predicted heat transfer against a larger amplitude. The results show good agreement for both training and testing data. The outcomes of analysis reveals that convection caused by temperature gradient is dominant for higher values of the Rayleigh number (Ra). Local Nusselt number has been discussed against different amplitudes, and predicted enhancement for the larger amplitude of the rod.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-12DOI: 10.1088/1402-4896/ad7547
Morteza Salehi
We theoretically show that an interface formed by a three-dimensional Dirac/magnetic Weyl semimetal deflects the propagation direction of hitting Weyl fermions according to their Chirality in opposite directions. This effect leads to a Chirality current that flows parallel to the interface. There is an imbalance between the Chirality of Weyl fermions in this current whereas it does not carry any charge. Also, this phenomenon creates an indirect gap in the charge conductance that pass through the circuit. Unlike real spin, Chirality remains a good quantum number in systems characterized by very strong spin-momentum coupling. We derive a continuity equation for the Chirality density wave to elucidate how magnetization alters its dynamics and relates to the transverse Chirality current. Furthermore, we demonstrate a torque, that we called it Chirality transfer torque, imposes on the junction that its value relates to the transverse Chirality current.
我们从理论上证明，由三维狄拉克/磁性韦尔半金属形成的界面会使撞击韦尔费米子的传播方向根据其奇异性向相反方向偏转。这种效应导致了平行于界面的手性电流。在这一电流中，Weyl 费米子的手性之间存在不平衡，而它并不携带任何电荷。此外，这种现象还会在通过电路的电荷传导中产生间接间隙。与真实自旋不同，手性在自旋-动量耦合非常强的系统中仍然是一个很好的量子数。我们推导出了手性密度波的连续性方程，以阐明磁化如何改变其动态以及与横向手性电流的关系。此外，我们还证明了一种我们称之为手性传递力矩（Chirality transfer torque）的力矩，它施加在结点上，其值与横向手性电流有关。
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