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Chloride penetration resistance of engineered cementitious composite (ECC) subjected to sustained flexural loading

Wang, Chuan (author), Sun, Renjuan (author), Hu, Xinlei (author), Guan, Yanhua (author), Yang, Yingzi (author), Lu, Wei (author), Tian, Jun (author), Zhang, Hongzhi (author), Ge, Zhi (author), Šavija, B. (author)

This paper presents a research on the chloride penetration behavior of engineered cementitious composites (ECC) under sustained flexural loads. Three load levels, i.e. 30 %, 60 % and 75 % of the ultimate flexural load were used. Chloride diffusion depth and concentration profile were measured 30, 60 and 150 days after the specimen was exposed...

journal article 2023

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The dependence of light extraction improvement on optimized surface microstructure for AlGaN-based UVC-LEDs considering TM-polarized emission

Zhu, Yifan (author), Lu, Huimin (author), Wang, Jianping (author), Yu, Tongjun (author), Li, Z.Z.L. (author), Tian, Yucheng (author)

In order to improve the light extraction of AlGaN-based short wavelength ultraviolet light emitting diodes (DUC-LEDs), a type of microstructure with high aspect ratio is introduced and optimized on the AlN substrate surface. And, particle swarm optimization (PSO) algorithm is used to inverse design of the surface microstructure to maximize...

journal article 2023

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The FluidFlower Validation Benchmark Study for the Storage of CO ₂

Flemisch, Bernd (author), Nordbotten, Jan M. (author), Geiger, S. (author), Hajibeygi, H. (author), Tian, X. (author), Voskov, D.V. (author), Wang, Y. (author), Wapperom, M.B. (author), Zhang, Z. (author)

Successful deployment of geological carbon storage (GCS) requires an extensive use of reservoir simulators for screening, ranking and optimization of storage sites. However, the time scales of GCS are such that no sufficient long-term data is available yet to validate the simulators against. As a consequence, there is currently no solid basis...

journal article 2023

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Efficient Angle Estimation for MIMO Systems via Redundancy Reduction Representation

Zhang, Yu (author), Wang, Yue (author), Tian, Zhi (author), Leus, G.J.T. (author), Zhang, Gong (author)

This paper proposes an efficient direction of departure (DOD) and direction of arrival (DOA) estimation method for multi-input multi-output (MIMO) systems. For uncorrelated scenarios, the redundancy of the covariance matrix is first exploited by establishing its concise representation through redundancy reduction, which transforms the...

journal article 2022

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Tuning homogenization of high-strength aluminum alloys through thermodynamic alloying approach

Wang, Yawen (author), Hou, Longgang (author), Su, Hui (author), Tian, Qingkun (author), Yu, Kangcai (author), Eskin, Dmitry (author), Katgerman, L. (author), Zhuang, Linzhong (author)

The alloy design and homogenization processes are intimately associated with the microstructure, phase composition and performance for Al-Zn-Mg-Cu alloys. The microstructures and phase composition of a series of Al-Zn-Mg-Cu alloys before and after the homogenization treatments were investigated along with thermodynamic calculation to...

journal article 2022

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Compound flood impact of water level and rainfall during tropical cyclone periods in a coastal city: the case of Shanghai

Xu, H. (author), Tian, Zhan (author), Sun, Laixiang (author), Ye, Qinghua (author), Ragno, E. (author), Bricker, J.D. (author), Tan, Jinkai (author), Ke, Q. (author), Wang, Shuai (author)

Compound flooding is generated when two or more flood drivers occur simultaneously or in close succession. Multiple drivers can amplify each other and lead to greater impacts than when they occur in isolation. A better understanding of the interdependence between flood drivers would facilitate a more accurate assessment of compound flood risk...

journal article 2022

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A Weighted Surrogate Model for Spatio-Temporal Dynamics with Multiple Time Spans: Applications for the Pollutant Concentration of the Bai River

Huan, Y. (author), Tian, Yubin (author), Wang, Dianpeng (author)

Simulations are often used to investigate the flow structures and system dynamics of complex natural phenomena and systems, which are significantly harder to obtain from experiments or theoretical analyses. Surrogate models are employed to mimic the results of simulations by reducing computational costs. In order to reduce the amount of...

journal article 2022

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Efficient Jacobian-Based Inverse Kinematics With Sim-to-Real Transfer of Soft Robots by Learning

Fang, G. (author), Tian, Yingjun (author), Yang, Zhi Xin (author), Geraedts, Jo M.P. (author), Wang, C.C. (author)

This article presents an efficient learning-based method to solve the <italic>inverse kinematic</italic> (IK) problem on soft robots with highly nonlinear deformation. The major challenge of efficiently computing IK for such robots is due to the lack of analytical formulation for either forward or inverse kinematics. To address...

journal article 2022

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Efficient Super-Resolution Two-Dimensional Harmonic Retrieval with Multiple Measurement Vectors

Zhang, Yu (author), Wang, Yue (author), Tian, Zhi (author), Leus, G.J.T. (author), Zhang, Gong (author)

This paper develops an efficient solution for super-resolution two-dimensional (2D) harmonic retrieval from multiple measurement vectors (MMV). Given the sample covariance matrix constructed from the MMV, a gridless compressed sensing approach is proposed based on the atomic norm minimization (ANM). In the approach, our key step is to perform...

journal article 2022

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Is the tropical cyclone surge in Shanghai more sensitive to landfall location or intensity change?

Wang, Shuai (author), Toumi, Ralf (author), Ye, Qinghua (author), Ke, Q. (author), Bricker, J.D. (author), Tian, Zhan (author), Sun, Laixiang (author)

It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing together with a poleward migration of TC track. However, their relative importance to TC surge at landfall remains unknown. Here we examine the sensitivity of TC surge in Shanghai to landfall location and intensity with a new dynamical modelling...

journal article 2021

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Reinforcement learning control of constrained dynamic systems with uniformly ultimate boundedness stability guarantee

Han, Minghao (author), Tian, Yuan (author), Zhang, Lixian (author), Wang, J. (author), Pan, W. (author)

Reinforcement learning (RL) is promising for complicated stochastic nonlinear control problems. Without using a mathematical model, an optimal controller can be learned from data evaluated by certain performance criteria through trial-and-error. However, the data-based learning approach is notorious for not guaranteeing stability, which is...

journal article 2021

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Direction of Arrival Estimation of Wideband Sources Using Sparse Linear Arrays

Wang, F. (author), Tian, Zhi (author), Leus, G.J.T. (author), Fang, Jun (author)

In this paper, we study the problem of wideband direction of arrival (DoA) estimation with sparse linear arrays (SLAs), where a number of uncorrelated wideband signals impinge on an SLA and the data is collected from multiple frequency bins. To boost the performance and perform underdetermined DoA estimation, the difference co-array response...

journal article 2021

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Small angle neutron scattering quantifies the hierarchical structure in fibrous calcium caseinate

Tian, B. (author), Wang, Zhaojun (author), de Campo, Liliana (author), Gilbert, Elliot P. (author), Dalgliesh, Robert M. (author), Velichko, E. (author), van der Goot, Atze Jan (author), Bouwman, W.G. (author)

Pronounced fibres are formed through simple shearing of a dense calcium caseinate dispersion. Both mechanical tests and scanning electron microscopy images demonstrate that the material is anisotropic. It is hypothesised that calcium caseinate aggregates, under shear, align into micro-fibres and bundle further into a hierarchical structure....

journal article 2020

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Physically-based landslide prediction over a large region: Scaling low-resolution hydrological model results for high-resolution slope stability assessment

Wang, S. (author), Zhang, Ke (author), van Beek, Ludovicus P.H. (author), Tian, X. (author), Bogaard, T.A. (author)

Rainfall-triggered shallow landslides are widespread natural hazards around the world, causing many damages to human lives and property. In this study, we focused on predicting landslides in a large region by coupling a 1 km-resolution hydrological model and a 90 m-resolution slope stability model, where a downscaling method for soil moisture...

journal article 2020

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Development of spectral-phenological features for deep learning to understand Spartina alterniflora invasion

Tian, Jinyan (author), Wang, Le (author), Yin, Dameng (author), Li, Xiaojuan (author), Diao, Chunyuan (author), Gong, Huili (author), Shi, Chen (author), Menenti, M. (author), Ge, Yong (author)

Invasive Spartina alterniflora (S. alterniflora), a native riparian species in the U.S. Gulf of Mexico, has led to serious degradation to the ecosystem and biodiversity as well as economic losses since it was introduced to China in 1979. Although multi-temporal remote sensing offers unique capability to monitor S. alterniflora over large...

journal article 2020

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Decadal morphological evolution of the mouth zone of the Yangtze Estuary in response to human interventions

Zhu, C. (author), Guo, Leicheng (author), van Maren, D.S. (author), Tian, Bo (author), Wang, Xianye (author), He, Qing (author), Wang, Zhengbing (author)

The morphology of the Yangtze Estuary has changed substantially at decadal time scales in response to natural processes, local human interference and reduced sediment supply. Due to its high sediment load, the morphodynamic response time of the estuary is short, providing a valuable semi-natural system to evaluate large-scale estuarine...

journal article 2019

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Air bubbles in calcium caseinate fibrous material enhances anisotropy

Wang, Zhaojun (author), Tian, B. (author), Boom, Remko (author), van der Goot, Atze Jan (author)

Dense calcium caseinate dispersions can be transformed into hierarchically fibrous structures by shear deformation. This transformation can be attributed to the intrinsic properties of calcium caseinate. Depending on the dispersion preparation method, a certain amount of air gets entrapped in the sheared protein matrix. Although anisotropy is...

journal article 2019

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Understanding the role of air and protein phase on mechanical anisotropy of calcium caseinate fibers

Wang, Zhaojun (author), Tian, B. (author), Boom, Remko (author), van der Goot, Atze Jan (author)

Calcium caseinate dispersions can be transformed into anisotropic, fibrous materials using the concept of shear-induced structuring. The aim of this study is to further investigate the relative importance of air bubbles and protein on the mechanical anisotropy of calcium caseinate material. In this study, the effect of air on mechanical...

journal article 2019

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Bas-Relief Modeling from Normal Layers

Wei, Mingqiang (author), Tian, Yang (author), Pang, Wai-Man (author), Wang, C.C. (author), Pang, Ming-Yong (author), Wang, Jun (author), Qin, Jin (author), Heng, Pheng-Ann (author)

Bas-relief is characterized by its unique presentation of intrinsic shape properties and/or detailed appearance using materials raised up in different degrees above a background. However, many bas-relief modeling methods could not manipulate scene details well. We propose a simple and effective solution for two kinds of bas-relief modeling (i...

journal article 2019

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Super-Resolution Channel Estimation for Arbitrary Arrays in Hybrid Millimeter-Wave Massive MIMO Systems

Wang, Yue (author), Zhang, Yu (author), Tian, Zhi (author), Leus, G.J.T. (author), Zhang, Gong (author)

This paper develops efficient channel estimation techniques for millimeter-wave (mmWave) massive multiple-input multiple-output (MIMO) systems under practical hardware limitations, including an arbitrary array geometry and a hybrid hardware structure. Taking on an angle-based approach, this work adopts a generalized array manifold separation...

journal article 2019