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Experimental study on drag coefficient of flexible vegetation under non-breaking waves

Reis, Rui A. (author), Fortes, Conceição J.E.M. (author), Rodrigues, José A. (author), Hu, Zhan (author), Suzuki, T. (author)

Laboratory experiments of wave propagation over rigid and flexible vegetation fields, with the same configurations, were conducted to understand the effect of vegetation flexibility on the drag coefficient (C_D). The direct method and the least squares method (LSM), based on force and flow measurements, are applied to calculate the...

journal article 2024

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Experimental and numerical investigation of the thermal inertia of sugar-beet-pulp/starch based bricks enhanced with phase change materials

Tenpierik, M.J. (author), Lachi, Mohammed (author), Bliard, Christophe (author), Polidori, Guillaume (author), Maalouf, Chadi (author)

Due to environmental concerns, bio-based materials are being increasingly investigated and used in buildings. In general, the density of these materials, and thus their thermal inertia, is low. Thermal inertia can be beneficial for reducing the energy use of buildings by damping indoor temperature fluctuations or by reducing and delaying...

journal article 2023

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Blast response of laminated glass: A gas-gun experimental investigation of the fracture pattern and yield lines observed in full-scale blast tests

Angelides, S. C. (author), Talbot, J. P. (author), Overend, M. (author)

The applications of architectural and automotive laminated glass continue to grow. This is largely due to the enhanced safety in extreme events, such as blast. However, the complex interaction between the glass fragments and the polymer interlayer after glass fracture is still only partially understood, with existing analysis methods adopting...

journal article 2023

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Overcoming inertia for sustainable urban development: Understanding the role of stimuli in shaping residents' participation behaviors in neighborhood regeneration projects in China

Fu, X. (author), Qian, QK (author), Liu, Guiwen (author), Zhuang, Taozhi (author), Visscher, H.J. (author), Huang, R. (author)

Neighborhood regeneration has become essential component of environmental improvement, and promoting resident participation is a key aspect of effective environmental management. However, in China, the legacy of the former housing allocation system and specific cultural contexts have led to residents' psychological inertia towards...

journal article 2023

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Cyber-Physical Testbed Co-simulation Real-Time: Normal and Abnormal System Frequency Response

Riquelme-Dominguez, Jose Miguel (author), Gonzalez-Longatt, Francisco (author), Melo, Andre Felipe Silva (author), Rueda, José L. (author), Palensky, P. (author)

Future carbon-neutral power systems impose many challenges; one is the urgent need for a simulation platform that allows replicating the complex systems’ actual dynamic performance. This paper shows the results of implementing a cyber-physical testbed co-simulation in real-time to analyse the system frequency response considering primary...

journal article 2023

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Explicit dynamic modeling with joint friction and coupling analysis of a 5-DOF hybrid polishing robot

Guo, Feng (author), Cheng, Gang (author), Pang, Y. (author)

Aiming at a 5-DOF hybrid optical mirror polishing robot, the explicit dynamic model considering the joint friction is established and the inertia coupling distribution is studied. Firstly, the kinematics of the manipulator is solved based on closed-loop vector method, and the dynamic model is established with Newton-Euler method based on the...

journal article 2022

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Verifying Machine Learning conclusions for securing Low Inertia systems

Bellizio, Federica (author), Bugaje, Al Amin B. (author), Cremer, Jochen (author), Strbac, Goran (author)

Machine Learning (ML) for real-time Dynamic Security Assessment (DSA) promises a probabilistic approach to secure lower safety margins and costs. However, future systems with a high share of renewables have low inertia and converter-interfaced devices resulting in faster dynamics. Past research on ML-based DSA used high inertia systems to...

journal article 2022

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Comparative study of SBOAs on the tuning procedure of the designed SMPI controller for MIMO VSP/HVDC interconnected model

Rakhshani, E. (author), Naveh, Iman Mohammad Hosseini (author), Mehrjerdi, Hasan (author)

This paper presents a new application of advanced SMPI controller for a newly introduced interconnected dynamic system with VSP based HVDC links for frequency control problem. This work presents an outgrowth of analysis about the Swarm – Based Optimization Algorithms (SBOAs) in the tuning process of Multivariable Proportional – Integral (MPI)...

journal article 2021

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An optimized LQG servo controller design using LQI tracker for VSP-based AC/DC interconnected systems

Rakhshani, E. (author), Naveh, Iman Mohammad Hosseini (author), Mehrjerdi, Hasan (author), Pan, K. (author)

This paper proposes a novel application for the optimal Linear Quadratic Gaussian (LQG) servo controller to enable a proper coordination of the AC/HVDC interconnected system with Virtual Synchronous Power (VSP) based inertia emulation. Particularly, the proposed control design takes the process disturbances and measurement noise of the...

journal article 2021

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Underfrequency Load Shedding using Locally Estimated RoCoF of the Center of Inertia

Sun, Mingyu (author), Liu, Gaoyuan (author), Popov, M. (author), Terzija, Vladimir (author), Azizi, Sadegh (author)

The conventional Under Frequency Load Shedding (UFLS) scheme could result in unacceptably low frequency nadirs or overshedding in power systems with volatile inertia. This paper proposes a novel UFLS scheme for modern power systems whose inertia may vary in a wide range due to high penetration of renewable energy sources (RESs). The proposed...

journal article 2021

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A Quasi-Oppositional Method for Output Tracking Control by Swarm-Based MPID Controller on AC/HVDC Interconnected Systems with Virtual Inertia Emulation

Naveh, Iman M. Hosseini (author), Rakhshani, E. (author), Mehrjerdi, Hasan (author), Elsaharty, Mohamed A. (author)

This paper presents a comprehensive evaluation of the effect of quasi oppositional - based learning method utilization in output tracking control through a swarm-based multivariable Proportional-Integral-Derivative (SMPID) controller, which is tuned by a novel performance index based on the step response characteristics in multi-input multi...

journal article 2021

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Electromechanical design of synchronous power controller in grid integration of renewable power converters to support dynamic stability

Abdollahi, Mostafa (author), Candela, Jose Ignacio (author), Tarraso, Andres (author), Atef Elsaharty, Mohamed (author), Rakhshani, E. (author)

Nowadays, modern power converters installed in renewable power plants can provide flexible electromechanical characteristics that rely on the developed control technologies such as Synchronous Power Controller (SPC). Since high renewable penetrated power grids result in a low-inertia system, this electromechanical characteristic provides...

journal article 2021

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Adaptive Control of HVDC Links for Frequency Stability Enhancement in Low-Inertia Systems

Stojković, J. (author), Lekić, A. (author), Stefanov, Predrag (author)

Decarbonization of power systems has put Renewable Energy Sources (RES) at the forefront when it comes to electric power generation. The increasing shares of converter-connected renewable generation cause a decrease of the rotational inertia of the Electric Power System (EPS), and consequently deteriorate the system capability to withstand large...

journal article 2020

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Defending the past by challenging the future: spatial and institutional path dependencies in the Naples port-city region

De Martino, P. (author)

Historical paths matter in port-city regions. Here, spatial patterns and governance arrangements are path dependent to the point that once certain paths have been established, these become hard to change. This defines a condition of institutional inertia that plays a significant role in preventing any form of spatial change. Naples is an...

journal article 2020

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FAPI Controller for Frequency Support in Low-Inertia Power Systems

Rakhshani, E. (author), Perilla Guerra, A.D. (author), Rueda, José L. (author), Gonzalez-Longatt, Francisco M. (author), Soeiro, Thiago B. (author), van der Meijden, M.A.M.M. (author)

This paper presents different forms of Fast Active Power Injection (FAPI) control schemes for the analysis and development of different mitigation measures to address the frequency stability problem due to the growth of the penetration level of the Power Electronic Interfaced Generation (PEIG) in sustainable interconnected energy systems. Among...

journal article 2020

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False Data Injection Attacks on Hybrid AC/HVDC Interconnected Systems with Virtual Inertia-Vulnerability, Impact and Detection

Pan, K. (author), Rakhshani, E. (author), Palensky, P. (author)

Power systems are moving towards hybrid AC/DC grids with the integration of HVDC links, renewable resources and energy storage modules. The load frequency control (LFC) of tomorrow has to consider the complex interactions between these components. Meanwhile, more attention should be paid to cyber security concerns as the LFC loop highly...

journal article 2020

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Jacobian-based natural frequency analysis of parallel manipulators

Hoevenaars, A.G.L. (author), Krut, S. (author), Herder, J.L. (author)

The dynamic performance of a parallel manipulator is often limited by its natural frequencies. These frequencies are a result of the controlled actuator stiffness and the mechanical design. Typically, only the lowest natural frequencies are of interest. However, existing methods to analyze natural frequencies of parallel manipulators with...

journal article 2020

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Effects of cyber attacks on ac and high-voltage DC interconnected power systems with emulated inertia

Pan, K. (author), Dong, J. (author), Rakhshani, E. (author), Palensky, P. (author)

The high penetration of renewable energy resources and power electronic-based components has led to a low-inertia power grid which would bring challenges to system operations. The new model of load frequency control (LFC) must be able to handle the modern scenario where controlled areas are interconnected by parallel AC/HVDC links and storage...

journal article 2020

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A Key Performance Indicator to Assess the Frequency Stability of Wind Generation Dominated Power System

Rakhshani, E. (author), Gusain, D. (author), Sewdien, V.N. (author), Rueda, José L. (author), van der Meijden, M.A.M.M. (author)

High penetration of power electronic interfaced generation, like wind power, has an essential impact on the inertia of the interconnected power system. It can pose a significant threat to the frequency stability. This paper introduces the notion of the key performance indicator (KPI) and illustrates its application on large scale power systems,...

journal article 2019

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Knowledge relationships of university spin-off firms: Contrasting dynamics in global reach

Taheri, M. (author), van Geenhuizen, M.S. (author)

This article provides an attempt to better understand the establishment of international knowledge relationships, including changes over time. Internationalization of young high-tech firms is strongly required given the drive for upscaling technology solutions and given the increased global spread of knowledge centers. To increase...

journal article 2019