作者机构：
[Xie, Liang; Lin, Xiang; Li, Zhe; Liu, Zhezheng; Jiang, Jishui] Cent South Univ, Sch Architecture & Art, Changsha 410075, Peoples R China.;[Xie, Liang; Lin, Xiang; Li, Zhe; Liu, Zhezheng; Jiang, Jishui] Cent South Univ, Hist Heritage Conservat Res Ctr, Changsha 410075, Peoples R China.;[Jiang, Jishui] Hunan City Univ, Sch Architecture & Urban Planning, Yiyang 413000, Peoples R China.
通讯机构：
[Li, Z ] C;Cent South Univ, Sch Architecture & Art, Changsha 410075, Peoples R China.;Cent South Univ, Hist Heritage Conservat Res Ctr, Changsha 410075, Peoples R China.
关键词：
western Hunan region;Dong;traditional settlement;fire prevention study;Pyrosim simulation
摘要：
Dopamine (DA) is an important neurotransmitter in human's brain, which has direct connection to diseases like Parkinson's disease, schizophrenia, etc. Therefore, the sensitive and rapid quantitative detection of DA is essential for medical diagnosis and disease prevention. To construct a novel electrochemical sensor for DA detection, nickel-based metal-organic frameworks (Ni-MOF) were synthesized through a hydrothermal method and combined with beta-cyclodextrin. Under optimal experimental conditions, the sensor exhibited a wide linear detection range (0.7-310.2 mu M) and a low detection limit (0.227 mu M). Furthermore, the sensor exhibited satisfactory stability and accuracy in an electrochemical study involving human serum and dopamine hydrochloride injection samples containing DA, and the redox mechanism of the sensor was elucidated. Overall, this study presents a novel electrochemical sensor based on cyclodextrins and MOFs for DA detection.
期刊：
Journal of Computational Methods in Sciences and Engineering,2023年23(1):433-443 ISSN：1472-7978
作者机构：
College of Teacher Education, Hunan City University, Yiyang, Hunan, China;Mechanical and Electrical Engineering College, Hunan City University, Yiyang, Hunan, China
关键词：
Deep learning;offline learning;classroom concentration;identification;measures
摘要：
During the reform of the deep teaching model, students’ deep learning quality was affected and restricted by various factors. During the offline class learning process of students, the concentration of deep learning directly affects the quality of learning. This article analyzes the study focus of students in deep learning models, conducts research on the quality of class offline learning of different students, quantifies the factors that affect students’ deep learning, and builds an analysis model for quantitative comparison. Important influence factor affecting students’ offline classroom concentration, through targeted measures, improve teaching methods and quality, optimize classroom teaching models, use various methods and measures to effectively improve learning focus, and further promote the reform of teaching models. The level of concentration of students’ learning has been steadily improved, and the model of deep learning is proposed to help the teaching model reform.
摘要：
An accurate estimation of earth pressure on retaining walls is imperative to achieving its design. This paper presents an analytical method framework that considers the effect of plant transpiration relative to the traditional calculation approaches. Specifically, a closed-form solution for one-dimensional steady unsaturated flow considering plant transpiration is incorporated into a representation of effective stress to obtain the changes in matric suction, and effective stress. The representations are used to extend Hooke's law and Rankine's earth pressure theory to determine at-rest, active, and passive earth pressures. Subsequently, the analytical method is used in a series of analysis case studies on the influence of root architecture types, transpiration rates, and soil types on earth pressure, to reveal that it can rapidly obtain the earth pressure. Notably, the effect of plant transpiration on earth pressure is significant. Furthermore, it is found that soil types and transpiration rates have a larger influence than root architecture types. Collectively, the research not only reveals the effect of plant on earth pressure for retaining wall, but also provides a theoretical basis for further exploration of the contribution of plants to the stability of retaining wall.
作者机构：
[Xu, Jun; Li, Xintao; Zheng, Kaihong; Pan, Fusheng; Kang, Yuehua; Zhou, Nan] Guangdong Acad Sci, Inst New Mat, Guangzhou 510650, Peoples R China.;[Zhao, Jun] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413002, Peoples R China.;[Yang, Hong; Jiang, Bin; Pan, Fusheng] Chongqing Univ, Coll Mat Sci & Engn, Natl Engn Res Ctr Magnesium Alloys, Chongqing 400044, Peoples R China.;[Yang, Hong; Jiang, Bin; Pan, Fusheng] Chongqing Inst Adv Light Met, Chongqing 400030, Peoples R China.;[Liu, Wenjun] Chongqing Univ Technol, Coll Mat Sci & Engn, Chongqing, Peoples R China.
通讯机构：
[Jun Xu] I;[Bin Jiang] N;Institute of New Materials, Guangdong Academy of Sciences, Guangzhou, China<&wdkj&>National Engineering Research Center for Magnesium Alloys, College of Materials Science and Engineering, Chongqing University, Chongqing, China<&wdkj&>Chongqing Institute for Advanced Light Metals, Chongqing, China
摘要：
Mg-3Al-1Zn (AZ31) sheets were produced by transverse gradient extrusion (TGE) process. The flow behavior and dynamic recrystallization during extrusion were systematically analyzed. The microstructures, textures, and mechanical behavior of extruded AZ31 sheet were also analyzed and compared with conventional extruded (CE) sheet. The results showed that fine grain structure and multi-type unique textures were formed in TGE sheet because of the generation of extra flow velocity along transverse direction (TD) and flow velocity gradient along extrusion direction (ED) during extrusion. The basal poles gradually deviated away normal direction (ND) from edge to center of the TGE sheet along TD, and the largest inclination angle at center region reached around 65 degrees. Furthermore, the basal poles inclined from ED to TD 40 degrees-63 degrees, except for the center region of TGE sheet. The TGE sheet presented higher ductility and strain hardening exponent (n-value), but lower yield strength and Lankford value (r-value) in comparison with the CE sheet. Both the basal <a> slip and tensile twins were easy to be activated during deformation, and the largest elongation of 41% and the lowest yield strength of 86.5 MPa were obtained for the ED-center sample in the TGE sheet.
摘要：
In this study, we present a novel analysis approach for lattice composite cylindrical shells reinforced with Graphene Platelets (GPL) nanoparticles. Our primary contribution lies in the investigation of these advanced structures, incorporating nanocomposite reinforcement, orthotropic inhomogeneity, and semi-analytical methods. The lattice composite comprises an anisogrid lattice laminated shell, reinforced with functionally graded GPL. We model this structure using a global continuous orthotropic deep shell approach, integrating the Halpin-Tsai and rule of mixtures homogenization strategies to estimate equivalent mechanical properties. We derive theoretical formulations utilizing Reddy's third-order shear deformation theory and nonlinear Sanders' kinematic assumptions, tailored for deep thick shells. Nonlinear equilibrium equations are obtained using Hamilton's principle and Hooke's constitutive law, leading to linearized bifurcation equations through adjacent-equilibrium and membrane pre-buckling analysis. Our stability analysis employs a semi-analytical method combining trigonometric expansion and Chebyshev collocation functions. Validation through parametric ex -amples demonstrates the accuracy and efficiency of our approach, unveiling insights into the impact of lattice composite and geometric parameters on the stability response of these innovative structures.
关键词：
3D Navier-Stokes-Voigt equations;admissible trajectories set;admissible control set;feedback control;time optimal control
摘要：
In this article, we discuss a time optimal feedback control for asymmetrical 3D Navier–Stokes–Voigt equations. Firstly, we consider the existence of the admissible trajectories for the asymmetrical 3D Navier–Stokes–Voigt equations by using the well-known Cesari property and the Fillippove’s theorem. Secondly, we study the existence result of a time optimal control for the feedback control systems. Lastly, asymmetrical Clarke’s subdifferential inclusions and asymmetrical 3D Navier–Stokes–Voigt differential variational inequalities are given to explain our main results.
作者机构：
[Luo, Xiaoyong; Long, Hao; Dong, Shuang; Luo, XY; Liu, Jinhong] Cent South Univ, Sch Civil Engn, Changsha 410000, Peoples R China.;[Long, Hao] Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;[Luo, Xiaoyong; Luo, XY] Cent South Univ, Hunan Prefabricated Bldg Engn Technol Res Ctr, Changsha 410000, Peoples R China.
通讯机构：
[Luo, XY ] C;Cent South Univ, Sch Civil Engn, Changsha 410000, Peoples R China.;Cent South Univ, Hunan Prefabricated Bldg Engn Technol Res Ctr, Changsha 410000, Peoples R China.
关键词：
prefabricated components;tolerance;manufacturing dimensions;dimensional chain;monte carlo method;installation reliability
摘要：
During the installation process of prefabricated components, deviations in dimensions and installation positions can occur due to construction quality issues, and the accumulation of these deviations can impact the reliability of component installation. However, the current approach to addressing accumulated deviations in the component installation process primarily relies on the trial-and-error method, lacking a solid theoretical foundation. This paper introduces the dimensional chain theory derived from mechanical engineering and presents a method to evaluate the installation reliability of prefabricated components in concrete structures. First, based on extensive measurements of installation deviations, it was found that the installation deviations of components followed a log-normal distribution. By analyzing the relationship between installation deviations and the acceptance rate, it was determined that for a 90% acceptance rate, the installation position deviation should be 8.6 mm for prefabricated wall panel components and 7.3 mm for prefabricated column components. Subsequently, the concept of dimensional chain theory from mechanical engineering was introduced to establish a limit state equation for quantifying the installation reliability of prefabricated components in concrete structures. By applying this theory, appropriate component fabrication dimensions could be determined to achieve a 95% level of installation reliability. Finally, by using the Monte Carlo method to solve the installation limit state equation for an actual engineering project, recommended fabrication dimensions for the components were obtained. The results indicate that within the horizontal axis, the length deviation of prefabricated beams, and the width fabrication dimension of columns needed to be reduced by 2.3 mm to 2.9 mm. Within the vertical axis, the length dimension of columns and the height dimension of beams had to be reduced by 0.9 mm to 2.2 mm to achieve a 95% level of installation reliability.
