Novel Asymptotic Synchronization Criteria on Riemann-Liouville Derivative Type Nonidentical Delayed Neural Networks

Hongmei Zhang,Hai Zhang,Weiwei Zhang,Chen Wang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.4

This article focuses on investigating the asymptotic synchronization of two nonidentical RiemannLiouville (R-L) fractional-order delayed neural networks (FDNNs). Compared with the existing literature, the considered model is concerned with the nonidentical FDNNs rather than identical NNs. Under a novel feedback controller, two asymptotic synchronization criteria on FDNNs are established by utilizing the Lyapunov direct method. The derived criteria are concise and easy to test in actual applications. A numerical example is given to verify the availability of the presented results for nonidentical FDNNs.

Cyclic load experiment study on the laminated composite RC walls with different concrete ages

Zhang, Hongmei,Lua, Xilin,Li, Jianbao,Liang, Lin Techno-Press 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.36 No.6

12 typical laminated composite reinforced concrete (RC) walls with different concrete ages and 3 cast-in-place RC walls subjected to low frequency cyclic load were carried out in this study. The failure mode, force-deformation response and energy dissipation capacity of these specimens were investigated. Differences of structural behaviours between composite RC walls and common cast-in-place RC walls were emphasized in the analysis. The compatibility of the composite specimens with different concrete ages was discussed based on the experiment. Test results indicated that the differences between the lateral bearing capacity and the displacement ductility of the composite walls and the common walls were not so obvious. Some of the composite specimen even has higher bearing capacity under the experiment loading situation. Besides, the two parts of the laminated composite specimens demonstrates incompatibility at the later loading sequence on failure mode and strain response when it is in tension. Finally, this laminated composite shear walls are suggested to be applied in rapid reconstruction structures which is not very high.

Pneumococcal wall teichoic acid is required for the pathogenesis of Streptococcus pneumoniae in murine models

Hongmei Xu,Libin Wang,Jian Huang,YanQing Zhang,Feng Ma,Jianmin Wang,WenChun Xu,XueMei Zhang,YiBing Yin,KaiFeng Wu 한국미생물학회 2015 The journal of microbiology Vol.53 No.2

Pneumococcal asymptomatic colonization of the respiratory tracts is a major risk for invasive pneumococcal disease. We have previously shown that pneumococcal wall teichoic acid (WTA) was involved in pneumococcal infection of sepsis and adherence to epithelial and endothelial cells. In this study, we investigated the contribution of pneumococcal WTA to bacterial colonization and dissemination in murine models. The result showed that nasopharynx colonizing D39 bacterial cells have a distinct phenotype showing an increased exposure of teichoic acids relative to medium-grown bacteria. The WTA-deficient mutants were impaired in their colonization to the nasopharynx and lungs, and led to a mild inflammation in the lungs at 36 h post-inoculation. Pretreatment of the murine nares with WTA reduced the ability of wild type D39 bacteria to colonize the nasopharynx. In addition, the WTA-deficient strain was impaired in its ability to invade the blood and brain following intranasal administration. WTA-deficient D39 strain was reduced in C3 deposition but was more susceptible to the killing by the neutrophils as compared with its parent strain. Our results also demonstrated that the WTA enhanced pneumococcal colonization and dissemination independently of the host strains. These results indicate that WTA plays an important role in pneumococcal pathogenesis, both in colonization and dissemination processes.

Comparison and prediction of seismic performance for shear walls composed with fiber reinforced concrete

Zhang, Hongmei,Chen, Zhiyuan Techno-Press 2021 Advances in concrete construction Vol.11 No.2

Concrete cracking due to brittle tension strength significantly prevents fully utilization of the materials for "flexural-shear failure" type shear walls. Theoretical and experimental studies applying fiber reinforced concrete (FRC) have achieved fruitful results in improving the seismic performance of "flexural-shear failure" reinforced concrete shear walls. To come to an understanding of an optimal design strategy and find common performance prediction method for design methodology in terms to FRC shear walls, seismic performance on shear walls with PVA and steel FRC at edge columns and plastic region are compared in this study. The seismic behavior including damage mode, lateral bearing capacity, deformation capacity, and energy dissipation capacity are analyzed on different fiber reinforcing strategies. The experimental comparison realized that the lateral strength and deformation capacity are significantly improved for the shear walls with PVA and steel FRC in the plastic region and PVA FRC in the edge columns; PVA FRC improves both in tensile crack prevention and shear tolerance while steel FRC shows enhancement mainly in shear resistance. Moreover, the tensile strength of the FRC are suggested to be considered, and the steel bars in the tension edge reaches the ultimate strength for the confinement of the FRC in the yield and maximum lateral bearing capacity prediction comparing with the model specified in provisions.

Hysteretic model of isolator gap damper system and its equivalent linearization for random earthquake response analysis

Hongmei Zhang,Chen Gu 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.29 No.3

In near-fault earthquake prone areas, the velocity pulse-like seismic waves often results in excessive horizontal displacement for structures, which may result in severe structural failure during large or near-fault earthquakes. The recently developed isolator-gap damper (IGD) systems provide a solution for the large horizontal displacement of long period base-isolated structures. However, the hysteresis characteristics of the IGD system are significantly different from the traditional hysteretic behavior. At present, the hysteretic behavior is difficult to be reflected in the structural analysis and performance evaluation especially under random earthquake excitations for lacking of effective analysis models which prevent the application of this kind of IGD system. In this paper, we propose a mathematical hysteretic model for the IGD system that presents its nonlinear hysteretic characteristics. The equivalent linearization is conducted on this nonlinear model, which requires the variances of the IGD responses. The covariance matrix for the responses of the structure and the IGD system is obtained for random earthquake excitations represented by the Kanai-Tajimi spectrum by solving the Lyapunov equation. The responses obtained by the equivalent linearization are verified in comparison with the nonlinear responses by the Monte Carlo simulation (MCS) analysis for random earthquake excitations.

New Stochastic Stability Criteria for Nonlinear Neutral Markovian Jump Systems

Hongmei Zhang,Jinde Cao,Lianglin Xiong 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.3

This paper address the stochastic stability of neutral markovian jumping systems with nonlinear perturbations. By constructing novel Lyapunov functionals which contain an augmented Lyapunov functional, andcombining with the new inequalities, new delay-dependent stochastic stability criteria for the nominal systems areobtained. The asymptotically stable condition is a special case for the stochastic stability condition as the systemswithout markovian jump. Numerical examples show that the derived conditions are much less conservative thanthose given in the existing literature.

Cyclic load experiment study on the laminated composite RC walls with different concrete ages

Hongmei Zhang,Xilin Lu,Jianbao Li,Lin Liang 국제구조공학회 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.36 No.6

12 typical laminated composite reinforced concrete (RC) walls with different concrete ages and 3 cast-in-place RC walls subjected to low frequency cyclic load were carried out in this study. The failure mode, force-deformation response and energy dissipation capacity of these specimens were investigated. Differences of structural behaviours between composite RC walls and common cast-in-place RC walls were emphasized in the analysis. The compatibility of the composite specimens with different concrete ages was discussed based on the experiment. Test results indicated that the differences between the lateral bearing capacity and the displacement ductility of the composite walls and the common walls were not so obvious. Some of the composite specimen even has higher bearing capacity under the experiment loading situation. Besides, the two parts of the laminated composite specimens demonstrates incompatibility at the later loading sequence on failure mode and strain response when it is in tension. Finally, this laminated composite shear walls are suggested to be applied in rapid reconstruction structures which is not very high.

Vector mechanics-based simulation of large deformation behavior in RC shear walls using planar four-node elements

Hongmei Zhang,Yufei Shan,Yuanfeng Duan,Chung Bang Yun,Song Liu 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.74 No.1

For the large deformation of shear walls under vertical and horizontal loads, there are difficulties in obtaining accurate simulation results using the response analysis method, even with fine mesh elements. Furthermore, concrete material nonlinearity, stiffness degradation, concrete cracking and crushing, and steel bar damage may occur during the large deformation of reinforced concrete (RC) shear walls. Matrix operations that are involved in nonlinear analysis using the traditional finite-element method (FEM) may also result in flaws, and may thus lead to serious errors. To solve these problems, a planar four-node element was developed based on vector mechanics. Owing to particle-based formulation along the path element, the method does not require repeated constructions of a global stiffness matrix for the nonlinear behavior of the structure. The nonlinear concrete constitutive model and bilinear steel material model are integrated with the developed element, to ensure that large deformation and damage behavior can be addressed. For verification, simulation analyses were performed to obtain experimental results on an RC shear wall subjected to a monotonically increasing lateral load with a constant vertical load. To appropriately evaluate the parameters, investigations were conducted on the loading speed, meshing dimension, and the damping factor, because vector mechanics is based on the equation of motion. The static problem was then verified to obtain a stable solution by employing a balanced equation of motion. Using the parameters obtained, the simulated pushover response, including the bearing capacity, deformation ability, curvature development, and energy dissipation, were found to be in accordance with the experimental observation. This study demonstrated the potential of the developed planar element for simulating the entire process of large deformation and damage behavior in RC shear walls.

EXPERIENCE VALUE CO-CREATION IN TOURISM LIVESCAPE: THE ROLE OF INSPIRATION AND ENGAGEMENT

Hongmei Zhang,Wenxiu Wu,Boyang Shu,Yijiang Yang 글로벌지식마케팅경영학회 2023 Global Marketing Conference Vol.2023 No.07

An important segment, tourism e-commerce live streaming (TEcLS) has emerged as a new marketing channel actively embraced by destination marketing organizations (DMO) and tourist firms due to the COVID-19 pandemic. China, Japan, Australia, and many other nations have been selling such tourism products on various platforms. Live e-commerce generates a real-time interactive virtual environment that can be called a livescape. However, many tourism destinations or companies are unaware of the marketing science implications of live streaming and are unsure of their effectiveness or the intricacies of marketing live streaming. Previous research has explored the factors influencing consumer purchase behavior from the product, technology, and live-streamer perspectives, arguing that the advantages of breaking through time and space constraints, strong interactivity, the experience of reality, technological ease of use and usefulness, and celebrity aura encourage online purchases. However, limited investigation has been carried out on the impact of customers’ value-co-creation in livescape when watching tourism live streaming on their purchase intentions considering the key role of engagement. This calls for specific investigation of the phenomenon to facilitate live streaming design and tourism marketing. This study aims to explores the factors influencing consumer purchase intentions in the livescape based on a value co-creation research framework. Compared to traditional e-commerce, livescapes provides the “many-to-many” social presence and an immersive value co-creation platform. Thus, we focus on why and how social presence inspires customer engagement, ultimately leading to purchase intentions. This study finds that, as a crucial marketing tool, the social presence of tourism livescapes can promotes customer engagement, which in turn results in intentions to purchase tourism live-streaming products. Additionally, the mediating role of inspiration (inspired-by and inspired-to) between social presence and customer engagement is examined to reveal the influence mechanism in the tourism context. Finally, this study examines how to create an effective tourism livescape to enhance tourists social presence experience and inspire their engagement, which in turn increases their purchase intention.

Adaptive Control Design and Fractional Differential Inequality Approach to Complete Synchronization Analysis on Caputo Delayed Quaternion-valued Network Systems

Xinbin Chen,Weiwei Zhang,Hongmei Zhang,Hai Zhang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.10

This article discusses the complete synchronization problem for the Caputo derivative quaternion-valued delayed neural networks (QVDNNs). A novel Caputo fractional differential inequality is constructed, and an algebraic inequality result is derived by using the Laplace transform. Applying such algebraic inequality result and designing an adaptive controller with Riemann-Liouville integral operator, the two complete synchronization criteria on the Caputo fractional QVDNNs are established based on the different Lyapunov functionals. The obtained results are presented in algebraic inequality forms, which can greatly reduce the computation complexities in checking the complete synchronization performance. Particularly, the advantages of the obtained criteria are obvious in dealing with high-dimensional network systems. Moreover, the validity of the proposed results is demonstrated by the numerical simulations.