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He, Xianqi (author), Yang, Lin (author), Lu, Chao (author), Gong, Jianwei (author), Li, Z. (author)In urban environments, the complex and uncertain intersection scenarios are challenging for autonomous driving. To ensure safety, it is crucial to develop an adaptive decision making system that can handle the interaction with other vehicles. Manually designed model-based methods are reliable in common scenarios. But in uncertain environments,...conference paper 2022
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Gao, Z. (author), He, J. (author), Fritz, Martin (author), Gong, J. (author), Shen, Y. (author), Zong, Z. (author), Chen, Peng (author), Staszewski, R.B. (author), Alavi, S.M. (author), Babaie, M. (author)In a fractional-N PLL, it is beneficial to minimize the input range of its phase detector (PD) as it promotes better linearity and higher PD gain for suppressing noise contributions of the following loop components. This can be done by canceling the predicted instantaneous time offset between the frequency reference (FREF) and the variable...conference paper 2022
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Yao, X. (author), He, Y. (author), Hessenberger, Norbert (author), Song, Y. (author), Vink, P. (author)During a flight, passengers spend most of their time sitting in their seats. Studying the comfort and discomfort while passengers are sitting is helpful to improve the overall comfort during a flight. Pressure mats are commonly used in studies to collect pressure distribution in order to research sitting comfort. Different from most past studies...conference paper 2021
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He, Nan (author), Yang, S. (author), Li, Fan (author), Trajanovski, S. (author), Kuipers, F.A. (author), Fu, Xiaoming (author)The efficacy of Network Function Virtualization (NFV) depends critically on (1) where the virtual network functions (VNFs) are placed and (2) how the traffic is routed. Unfortunately, these aspects are not easily optimized, especially under time-varying network states with different quality of service (QoS) requirements. Given the importance of...conference paper 2021
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Igl, Maximilian (author), Gambardella, Andrew (author), He, J. (author), Nardelli, Nantas (author), Siddharth, N (author), Böhmer, J.W. (author), Whiteson, Shimon (author)We present Multitask Soft Option Learning (MSOL), a hierarchical multitask framework based on Planning as Inference. MSOL extends the concept of options, using separate variational posteriors for each task, regularized by a shared prior. This “soft” version of options avoids several instabilities during training in a multitask setting, and...conference paper 2020
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He, L. (author), de Weerdt, M.M. (author), Yorke-Smith, N. (author)An important class of scheduling problems is characterised by time-dependency and/or sequence-dependency with time windows. We introduce and analyze four algorithmic ideas for this class: a novel hybridization of adaptive large neighbourhood search (ALNS) and tabu search (TS), randomized generic neighbourhood operators, a partial sequence...conference paper 2019
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Sun, P. (author), Van Mieghem, P.F.A. (author), Kooij, Robert (author), He, Z. (author), Van Mieghem, Piet (author)In this paper, we propose closed-form analytic approximations for the minimum number of driver nodes needed to fully control networks, where links are removed according to both random and targeted attacks. Our approximations rely on the concept of critical links. A link is called critical if its removal increases the required number of driver...conference paper 2019
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He, Z. (author), Sun, P. (author), Van Mieghem, P.F.A. (author)Network recoverability refers to the ability of a network to return to a desired performance level after suffering malicious attacks or random failures. This paper proposes a general topological approach and recoverability indicators to measure the network recoverability in two scenarios: 1) recovery of damaged connections and 2) any...conference paper 2019
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van Duin, Ron (author), Wiegmans, B. (author), Tavasszy, Lorant (author), Hendriks, B. (author), He, Y. (author)Five years ago the project Cargo Hitching started with the goal to use the unused capacity of public transport passenger vehicles for freight and parcel transport. Like many new city logistics initiatives it is a difficult challenge to setup a profitable private business model. A rural pilot project was developed in the East of the Netherlands,...conference paper 2018
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He, L. (author), de Weerdt, M.M. (author), Yorke-Smith, N. (author), Liu, Xiaolu (author), Chen, Yingwu (author)Agile Earth observation satellite (AEOS) scheduling is complex, due to long visible time windows and time-dependent transitions between observations. We introduce a generic approach suited for scheduling problems characterised by time-dependency and/or sequence-dependency. Our approach is a novel hybridization of adaptive large neighbourhood...conference paper 2018
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Dabrowski, M.M. (author), Stead, D. (author), Yu, Feng (author), He, J. (author)In some of the delta cities which are the most exposed to flooding caused by climate change - like Shenzhen and Guangzhou investigated in this paper - there is surprisingly little recognition of this problem and hardly any action is taken to address it. This paper draws on the insights from these two cases to address the following research...conference paper 2016
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We report experimental results for the temperature variance 2(z) and the corresponding frequency spectra P(f) in turbulent Rayleigh-Bénard convection (RBC) in a cylindrical sample of aspect ratioT= D/L = 1:00 (D = 1:12 m is the diameter and L = 1:12 m the height). The measurements were conducted in the Rayleigh-number range 1011 < Ra < 1:35 1014...conference paper 2015
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We report on measurements of the ultimate-state transition in turbulent Rayleigh-B\'enard convection obtained in a large facility known as the ``Uboot of G\"ottingen" and using pressurized sulfur hexafluoride as the convecting fluid. We found that the transition occurs over a range of $Ra$ which becomes more narrow as $\Gamma$ increases, ranging...conference paper 2015
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The evolution of coherent structures in a flat plate boundary layer transition induced by the cylinder wake is investigated using the particle image velocimetry (PIV) technique. The finite-time Lyapunov exponent (FTLE), which characterizes the amount of stretching about the flow trajectory, is used to extract the Lagrangian coherent structures....conference paper 2015
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We report on measurements of the mean-flow Reynolds number ReU and the rms fluctuation Reynolds number ReV in turbulent Rayleigh-Bénard convection as a function of the Rayleigh number Ra for 4 x 1011 < Ra < 2 1014 and Pr ' 0:8. Both can be described by the same power law with an effective exponent = 0:44, in agreement with predictions for ReU...conference paper 2015
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Thermally driven turbulent convection under the influence of global rotation is ubiquitous in nature. Well known examples are the outer convective shell of our Sun and the outer liquid core of the Earth. Trying to understand the underlying dynamics of such flows is highly challenging, not only because of the enormous range in length- and time...conference paper 2015
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Li, Zi Ru (author), Zhang, Guang Ming (author), He, Wei Dong (author), van Terwisga, T.J.C. (author)In this paper, the unsteady cavitation phenomena on a NACA0015 hydrofoil is numerically simulated by unsteady Reynolds-Averaged Navier-Stokes (URANS) method and Large Eddy Simulation (LES) in single-fluid approaches to multiphase modelling, respectively. It is observed that the large-scale structures and characteristic periodic shedding...conference paper 2015
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Guo, Renzhong (author), Luo, Feng (author), Zhao, Zhigang (author), He, Biao (author), Li, Lin (author), Luo, Ping (author), Ying, Shen (author)As the economy and urbanization develop, the expansion of the city not only develops towards the horizontal space, but also towards the vertical space. Facing the development of three-dimensional (3D) space, the traditional two-dimensional (2D) cadastral management mode cannot satisfy the need of current 3D land use and urban plan, so developing...conference paper 2014
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- Stroeven, P. (author), He, H. (author), Le, L.B.N. (author), Li, K. (author) conference paper 2014
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Zhang, M. (author), He, Q. (author), Gong, J. (author)Composable modeling method has been a research hotpot in the area of Modeling and Simulation for a long time. In order to increase the reuse and interoperability of BOM based model, this paper put forward a composable modeling method based on BOM, studied on the basic theory of composable modeling method based on BOM, designed a general...conference paper 2013