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Liu, D. (author), Wang, H. (author), Van Mieghem, P. (author)In recent years, many network perturbation techniques, such as topological perturbations and service perturbations, were employed to study and improve the robustness of complex networks. However, there is no general way to evaluate the network robustness. In this paper, we propose a global measure for a network, the reconstructability...journal article 2010
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- Van Mieghem, P.F.A. (author), Stevanovic, D (author), Kuipers, F.A. (author), Li, C. (author), van de Bovenkamp, R. (author), Liu, D. (author), Wang, H. (author) journal article 2011
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Van Mieghem, P. (author), Stevanovi?, D. (author), Kuipers, F. (author), Li, C. (author), Van de Bovenkamp, R. (author), Liu, D. (author), Wang, H. (author)The decrease of the spectral radius, an important characterizer of network dynamics, by removing links is investigated. The minimization of the spectral radius by removing m links is shown to be an NP-complete problem, which suggests considering heuristic strategies. Several greedy strategies are compared, and several bounds on the decrease of...journal article 2011
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Liu, D. (author), Blenn, N. (author), Van Mieghem, P.F.A. (author)ur society contains all types of organizations, such as companies, research groups and hobby clubs. Affliation networks, as a large and important portion of social networks, consist of individuals and their affiation relations: Two individuals are connected by a link if they belong to the same organization(s). Affliation networks naturally...journal article 2012
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Liu, D. (author), Blenn, N. (author), Van Mieghem, P.F.A. (author)Social networks, as well as many other real-world networks, exhibit overlapping community structure. In this paper, we present formulas which facilitate the computation for characterizing the overlapping community structure of networks. A hypergraph representation of networks with overlapping community structure is introduced. Using the...journal article 2012
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Liu, D. (author), Trajanovski, S. (author), Van Mieghem, P. (author)For a fixed number N of nodes, the number of links L in the line graph H(N,L) can only appear in consecutive intervals, called a band of L. We prove that some consecutive integers can never represent the number of links L in H(N,L), and they are called a bandgap of L. We give the exact expressions of bands and bandgaps of L. We propose a model...journal article 2013
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Liu, D. (author), Trajanovski, S. (author), Van Mieghem, P. (author)This paper presents a new and efficient algorithm, ILIGRA, for inverse line graph construction. Given a line graph H, ILIGRA constructs its root graph G with the time complexity being linear in the number of nodes in H. If ILIGRA does not know whether the given graph H is a line graph, it firstly assumes that H is a line graph and starts its...journal article 2014
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Song, X. (author), Liu, D. (author), Polinder, H. (author), Mijatovic, Nenad (author), Holbøll, Joachim (author), Jensen, Bogi Bech (author)Direct drive high temperature superconducting (HTS) wind turbine generators have been proposed to tackle challenges for ever increasing wind turbine ratings. Due to smaller reactances in HTS generators, higher fault currents and larger transient torques could occur if sudden short circuits happen at generator terminals. In this paper, a finite...journal article 2017
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Liu, D (author), Šavija, B. (author), Smith, G.E. (author), Flewitt, P.E.J. (author), Lowe, T. (author), Schlangen, E. (author)In this work, porosity-property relationships of quasi-brittle materials are explored through a combined experimental and numerical approach. In the experimental part, hemihyrate gypsum plaster powder (CaSO 4 ⋅1/2H 2 O CaSO4⋅1/2H2O) and expanded spherical polystyrene beads (1.5–2.0 mm dia.) have been mixed to form a model material with...journal article 2017
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Liu, D. (author), Kenjeres, S. (author)In the present study, we address the development and application of an efficient tool for conversion of results obtained by an integrated computational fluid dynamics (CFD) and computational reaction dynamics (CRD) approach and their visualization in the Google Earth. We focus on results typical for environmental fluid mechanics studies at a...journal article 2017
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Liu, D. (author), Polinder, H. (author), Abrahamsen, Asger B. (author), Ferreira, Jan Abraham (author)This paper aims at assessing the potential of partially superconducting generators for 10 MW direct-drive wind turbines by investigating their performance for a very wide range of excitation currents. Performance indicators such as shear stress and efficiency and other generator characteristics are compared for 12 different generator topologies....journal article 2017
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Liu, D. (author), Tito, Nicholas B. (author), Broer, Dirk J. (author)Coatings with a dynamic surface topography are of interest for applications in haptics, soft robotics, cell growth in biology, hydro- and air dynamics and tribology. Here we propose a design for creating oscillating surface topographies in thin liquid crystal polymer network coatings under an electric field. By applying an alternating...journal article 2017
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Abrahamsen, Asger Bech (author), Liu, D. (author), Magnusson, Niklas (author), Thomas, Arwyn (author), Azar, Ziad (author), Stehouwer, Ewoud (author), Hendriks, Ben (author), Van Zinderen, Gerrit-Jan (author), Deng, Fujin (author), Chen, Zhe (author), Karwatzki, Dennis (author), Mertens, Axel (author), Parker, Max (author), Finney, Stephen (author), Polinder, H. (author)A method for comparing the levelized cost of energy (LCoE) of different superconducting drive trains is introduced. The properties of a 10-MW MgB<sub>2</sub> superconducting direct-drive generator and the cost break down of the nacelle components are presented and scaled up to a turbine with a rotor diameter of up to 280 m. The partial load...journal article 2018
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Liu, Nan (author), Liu, D. (author), Wang, Weifei (author), Hollmann, F. (author), Xu, Long (author), Ma, Yunjian (author), Yang, Bo (author), Bai, Weidong (author), Sun, Xiaotao (author), Wang, Yonghua (author)α‐Linolenic acid‐rich diacylglycerol has been demonstrated with promising health promotion functions. This study examined the production, immobilization of lipase PCL, and its application in the synthesis of diacylglycerol by esterification of α‐linolenic acid with glycerol. The resin ECR8806 was selected as an effective support for the...journal article 2018
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Šavija, B. (author), Smith, G.E. (author), Liu, D (author), Schlangen, E. (author), Flewitt, P.E.J. (author)Deformation and fracture of materials are usually considered in terms of brittle and ductile modes. However, there is an intermediate class between these limits that is termed quasi-brittle where there is measurable inelastic deformation prior to final graceful ‘brittle’ failure. In previous work, we presented deformation and fracture data...journal article 2018
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Liu, D. (author), Yu, Wenwu (author), Baldi, S. (author), Cao, Jinde (author), Huang, Wei (author)The work presented in this paper concerns a switching-based control formulation for multi-intersection and multiphase traffic light systems. A macroscopic traffic flow modeling approach is first presented, which is instrumental to the development of a model-based and switching-based optimization method for traffic signal operation, in the...journal article 2020
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Liu, D. (author), Song, X. (author), Deng, Fujin (author), Dong, J. (author)High-Temperature superconducting (HTS) generators are being considered as a competitive candidate in large direct-drive (DD) wind turbines because of their features of being lightweight and compact. Normally a large air gap is inevitable in partially HTS generators, sacrificing the torque producing capability. In this paper, multi-phase...journal article 2020
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Liu, D. (author), van den Boom, S.J. (author), Simone, A. (author), Aragon, A.M. (author)We propose an enriched finite element formulation to address the computational modeling of contact problems and the coupling of non-conforming discretizations in the small deformation setting. The displacement field is augmented by enriched terms that are associated with generalized degrees of freedom collocated along non-conforming...journal article 2022
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Zhang, J. (author), Zhebel, E.V. (author), van den Boom, S.J. (author), Liu, D. (author), Aragon, A.M. (author)In this work, an object-oriented geometric engine is proposed to solve problems with discontinuities, for instance, material interfaces and cracks, by means of unfitted, immersed, or enriched finite element methods (FEMs). Both explicit and implicit representations, such as geometric entities and level sets, are introduced to describe...journal article 2022