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Wei, Zilong (author), Sun, Xianfu (author), Yang, Fei (author), Ke, Zaitian (author), Lu, Tao (author), Zhang, P. (author), Shen, C. (author)The presence of rail corrugation enlarges the wheel-rail impact and exacerbates the failure of track components, and the situation becomes even worse under high train speed, which promotes the urgent need for an efficient and easily accessible inspection method. Conventional diagnosis approaches such as axle box acceleration (ABA) and image...journal article 2022
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Qian, N. (author), Chang, Guobin (author), Gao, Jingxiang (author), Shen, Wenbin (author), Yan, Z. (author)Filtering for GRACE temporal gravity fields is a necessary step before calculating surface mass anomalies. In this study, we propose a new denoising and decorrelation kernel (DDK) filtering scheme called adaptive DDK filter. The involved error covariance matrix (ECM) adopts nothing but the monthly time‐variable released by several data...journal article 2022
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Bootsman, R.J. (author), Mul, D.P.N. (author), Shen, Y. (author), Hashemi, M. (author), Heeres, Rob M. (author), van Rijs, Fred (author), Alavi, S.M. (author), de Vreede, L.C.N. (author)Fully digital transmitters (DTXs) have the potential of replacing analog-intensive transmitter (TX) line-ups in future massive multiple-input and multiple-output (mMIMO) systems since they hold the promise of higher system integration level and energy efficiency. DTX operation so far has been limited to low RF output powers. This article...journal article 2022
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Zhang, F. (author), Westra, Kevin (author), Shen, Q. (author), Batashev, I. (author), Kiecana, A. (author), van Dijk, N.H. (author), Brück, E.H. (author)The novel all-d-metal Ni(Co)MnTi based magnetic Heusler alloys provide an adjustable giant magnetocaloric effect and good mechanical properties. We report that the second-order magnetic phase transition can be tailored in this all-d-metal NiCoMnTi based Heusler system by optimizing the Mn/Ti ratio, resulting in a reversible ferromagnetic-to...journal article 2022
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Beikmirza, M.R. (author), Shen, Y. (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)A 40nm CMOS wideband digital Cartesian push-pull inverted Doherty operating in class-E is presented. Wideband Doherty operation is achieved over a 1.9-to-3GHz frequency band, using an off-chip power combining network. The fully digital transmitter (DTX) provides 25.3dBm peak power with a drain/DTX line-up efficiency (DE/SE) of 58.7%/44.9%,...conference paper 2022
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Bootsman, R.J. (author), Shen, Y. (author), Mul, D.P.N. (author), Rousstia, Mohadig (author), Heeres, Rob (author), van Rijs, Fred (author), Gajadharsing, John (author), Alavi, S.M. (author), de Vreede, L.C.N. (author)A high-power fully-digital Doherty transmitter (DDTX) is proposed. It features two segmented LDMOS output switch banks implemented in a custom V T -down-shifted LDMOS technology. A 40 nm CMOS controller digitally activates the individual LDMOS gate segments of the output stage at RF speed. An inverted Doherty power combiner is proposed that...conference paper 2022
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Yang, Jun (author), Chen, Yongjun (author), Gurvits, L. (author), Paragi, Zsolt (author), Yang, Aiyuan (author), Yang, Xiaolong (author), Shen, Zhiqiang (author)In the time domain, the radio sky in particular along the Galactic plane direction may vary significantly because of various energetic activities associated with stars, stellar, and supermassive black holes. Multi-epoch Very Large Array surveys of the Galactic plane at 5.0 GHz enabled the finding of a catalogue of 39 variable radio sources in...journal article 2022
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WANG, J. (author), Schrade, Constantin (author), Levajac, V. (author), van Driel, D. (author), Li, K. (author), Badawy, G.H.A. (author), Lee, J.S. (author), Kouwenhoven, Leo P. (author), Shen, Jie (author)We study a Cooper pair transistor realized by two Josephson weak links that enclose a superconducting island in an InSb-Al hybrid nanowire. When the nanowire is subject to a magnetic field, isolated subgap levels arise in the superconducting island and, because of the Coulomb blockade, mediate a supercurrent by coherent cotunneling of Cooper...journal article 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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Song, Minyoung (author), Huang, Yu (author), Shen, Yiyu (author), Shi, Chengyao (author), Breeschoten, Arjan (author), Konijnenburg, Mario (author), Visser, Huib (author), Romme, J.P.A. (author), Dutta, Barundeb (author), Alavi, S.M. (author)Intra-cortical extracellular neural sensing is being rapidly and widely applied in several clinical research and brain-computer interfaces (BCIs), as the number of sensing channels continues to double every 6 years. By distributing multiple high-density extracellular micro-electrode arrays (MEAs) in vivo across the brain, each with 1000's of...conference paper 2022
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Gomez Ortega, A. (author), van Kollenburg, Janne (author), Shen, Yvette (author), Murray-Rust, D.S. (author), Nedić, Dajana (author), Jimenez Garcia, Juan (author), Meijer, Wo (author), Kumar Chaudhary, Pranshu (author), Bourgeois, Jacky (author)Designers and HCI researchers from industry and academia have been exploring the opportunities that emerge from incorporating behavioral data into the design process. For this, designers employ and combine data from multiple sources, multiple scales, and types to obtain valuable insights that inform and support design decisions. This combination...conference paper 2022
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Xu, Xing (author), Lin, Kaiyi (author), Yang, Yang (author), Hanjalic, A. (author), Shen, Heng Tao (author)Recently, generative adversarial network (GAN) has shown its strong ability on modeling data distribution via adversarial learning. Cross-modal GAN, which attempts to utilize the power of GAN to model the cross-modal joint distribution and to learn compatible cross-modal features, is becoming the research hotspot. However, the existing cross...journal article 2022
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Shen, Y. (author)This thesis focuses on digital-intensive up-converters for sub-6GHz wireless communication. Nowadays, wireless cellular communication is entering its 5th generation (5G), driven by the demand for faster mobile access and higher data throughput. 5G utilizes larger modulation bandwidths, higher-order modulations, and (many) more transmitters and...doctoral thesis 2021
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Ni, Chenxin (author), Yu, Zhuqing (author), Shen, Xiaodong (author)As one of the mineral admixtures, silica fume (SF) with high pozzolanic reactivity is generally used to improve the properties of concrete. Most commercial silica fume used in concrete project is dry densified silica fume (DSF). It consists of a good deal of agglomerates of sizes ranging from 10 μm to several millimeters. The size of the...conference paper 2021
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Wan, Xiaomei (author), Shen, Chen (author), Zhao, Tiejun (author)Ultra-high toughness geopolymer composites (UHTGC) were fabricated based on the matrix of binder composed of alkali-activated fly-ash and granulated blast furnace slag and polyvinyl alcohol (PVA) fibres in this research. The tensile behaviour and fracture toughness of UHTGC are investigated on both macro and microscales experimentally and...conference paper 2021
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Wu, Changsheng (author), Rwei, A.Y. (author), Lee, Jong Yoon (author), Ouyang, Wei (author), Jacobson, Lauren (author), Shen, Haixu (author), Luan, Haiwen (author), Xu, Yameng (author), Li, S. (author)Background Current near-infrared spectroscopy (NIRS)-based systems for continuous flap monitoring are highly sensitive for detecting malperfusion. However, the clinical utility and user experience are limited by the wired connection between the sensor and bedside console. This wire leads to instability of the flap-sensor interface and may...journal article 2021
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Beikmirza, M.R. (author), Shen, Y. (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)We present a wideband, 12-bit four-way Doherty Cartesian digital transmitter (DTX) featuring an innovative 50%-LO signed I/Q interleaved up-conversion technique that enables close to perfect orthogonal I/Q summation. The DTX incorporates a compact four-way lumped-element Doherty power combining network to enhance its average efficiency at...journal article 2021
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Shen, C. (author), Deng, X. (author), Wei, Z. (author), Dollevoet, R.P.B.J. (author), Zoeteman, A. (author), Li, Z. (author)A singular rail or wheel surface irregularity, such as a squat, insulation joint or wheel flat, can cause large wheelrail impact force. Both the magnitude and frequency content of the impact force need to be correctly modelledbecause they are closely related to the formation, deterioration and detection of such irregularities. In this paper,we...journal article 2021
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Shen, C. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)We propose to combine a physics-based finite element (FE) track model and a data-driven Gaussian process regression (GPR) model to directly infer railpad and ballast stiffness from measured frequency response functions (FRF) by field hammer tests. Conventionally, only the rail resonance and full track resonance are used as the FRF features to...journal article 2021
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Yang, Fei (author), Wei, Zilong (author), Sun, Xianfu (author), Shen, C. (author), Nunez, Alfredo (author)In this study, a wheel-rail transient rolling contact model capable of accounting for the nonlinear displacement-force properties of hanging sleepers is proposed. The sleeper hanging status affected by rail irregularities is an input for an analysis of the wheel-rail contact behavior and related rail degradation in terms of plastic...journal article 2021