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A Low-Spur Fractional-N PLL Based on a Time-Mode Arithmetic Unit

Gao, Z. (author), He, J. (author), Fritz, Martin (author), Shen, Y. (author), Zong, Z. (author), Spalink, Gerd (author), Alavi, S.M. (author), Staszewski, R.B. (author), Babaie, M. (author)

This article introduces a low-jitter low-spur fractional-N phase-locked loop (PLL) adopting a new concept of a time-mode arithmetic unit (TAU) for phase error extraction. The TAU is a time-signal processor that calculates the weighted sum of input time offsets. It processes two inputs - the period of a digitally controlled oscillator (DCO)...

journal article 2023

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Fast-responsive capsule based on two soluble components for self-healing concrete

Gao, Jian (author), Jin, Peng (author), Zhang, Yuze (author), Dong, H. (author), Wang, Ruixing (author)

Due to low activity or long mineralization time, traditional mineral agents for self-healing concrete generally need a long time to achieve a desired repair efficiency. Inspired by epoxy resin AB glue which can consolidate in a short time when mixing the two components together, a novel type of fast-responsive capsules based on two soluble...

journal article 2022

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Microwave heating mechanism and Self-healing performance of scrap tire pyrolysis carbon black modified bitumen

Wang, Fu (author), Zhu, Hongbin (author), Li, Yuanyuan (author), Gu, Dengjun (author), Gao, Y. (author), Feng, Jianlin (author), Shu, Benan (author), Li, Chao (author), Wu, Shaopeng (author)

Conventional asphalt mixture has poor microwave absorbing performance and microwave heating efficiency. Based on the characteristics of dielectric loss of scrap tire pyrolysis carbon black (PCB), it is proposed to improve the microwave absorbing performance and self-healing rate of bitumen. The phase composition and electromagnetic parameters...

journal article 2022

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Estimating loss of life caused by dam breaches based on the simulation of floods routing and evacuation potential of population at risk

Ge, Wei (author), Jiao, Yutie (author), Wu, Meimei (author), Li, Zongkun (author), Wang, Te (author), Li, Wei (author), Zhang, Yadong (author), Gao, Weixing (author), van Gelder, P.H.A.J.M. (author)

Dam breaches often have catastrophic consequences in downstream areas. Hydrodynamic factors and the evacuation potential of the population at risk (PAR) have significant impacts on the loss of life (LOL) caused by dam breaches. However, the existing comprehensive evaluation models have not conducted in-depth research on the evacuation...

journal article 2022

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Adaptive DDK Filter for GRACE Time‐Variable Gravity Field with a Novel Anisotropic Filtering Strength Metric

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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Generalized Single-Vehicle-Based Graph Reinforcement Learning for Decision-Making in Autonomous Driving

Yang, Fan (author), Li, Xueyuan (author), Liu, Qi (author), Li, Z. (author), Gao, Xin (author)

In the autonomous driving process, the decision-making system is mainly used to provide macro-control instructions based on the information captured by the sensing system. Learning-based algorithms have apparent advantages in information processing and understanding for an increasingly complex driving environment. To incorporate the...

journal article 2022

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Multi-Agent Decision-Making Modes in Uncertain Interactive Traffic Scenarios via Graph Convolution-Based Deep Reinforcement Learning

Gao, Xin (author), Li, Xueyuan (author), Liu, Qi (author), Li, Z. (author), Yang, Fan (author), Luan, Tian (author)

As one of the main elements of reinforcement learning, the design of the reward function is often not given enough attention when reinforcement learning is used in concrete applications, which leads to unsatisfactory performances. In this study, a reward function matrix is proposed for training various decision-making modes with emphasis on...

journal article 2022

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Bilevel Model for Protection-Branch Measurements-Based Topology Attack Against DC and AC State Estimations

Gao, Shibin (author), He, Zonglun (author), Wei, Xiaoguang (author), Liu, Y. (author), Huang, Tao (author), Lei, Jieyu (author)

A topology attack, as a special class of false data injection attacks, tampers with topology information of a system to mislead the decision of the control center. This article conducts an in-depth study on topology attacks that aim to interfere with the judgment in topology information and pose potential damage by tampering with measurement...

journal article 2022

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Assembly of Core/Shell Nanospheres of Amorphous Hemin/Acetone-Derived Carbonized Polymer with Graphene Nanosheets for Room-Temperature NO Sensing

Wang, Jianqiang (author), Gao, Yixun (author), Chen, Fengjia (author), Zhang, Lulu (author), Li, Hao (author), De Rooij, Nicolaas Frans (author), Umar, Ahmad (author), Lee, Yi Kuen (author), French, P.J. (author)

Implementing parts per billion-level nitric oxide (NO) sensing at room temperature (RT) is still in extreme demand for monitoring inflammatory respiratory diseases. Herein, we have prepared a kind of core-shell structural Hemin-based nanospheres (Abbr.: Hemin-nanospheres, defined as HNSs) with the core of amorphous Hemin and the shell of...

journal article 2022

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Evaluating the stray current corrosion of steel rebar in different layouts

Chen, Zhipei (author), Gao, Liang (author), Koleva, D.A. (author)

By different testing methods (electrochemical techniques, potential shift monitoring, and Environmental Scanning Electron Microscope), this research evaluates the stray current corrosion of steel rebar in different layouts. The more significant corrosion state is observed when the steel bar is parallel to stray current flow, compared to the...

journal article 2022

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Frozen soil hydrological modeling for a mountainous catchment northeast of the Qinghai-Tibet Plateau

Gao, Hongkai (author), Han, Chuntan (author), Chen, Rensheng (author), Feng, Zijing (author), Wang, Kang (author), Fenicia, Fabrizio (author), Savenije, Hubert (author)

Increased attention directed at frozen soil hydrology has been prompted by climate change. In spite of an increasing number of field measurements and modeling studies, the impact of frozen soil on hydrological processes at the catchment scale is still unclear. However, frozen soil hydrology models have mostly been developed based on a bottom...

journal article 2022

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A 23-μW Keyword Spotting IC With Ring-Oscillator-Based Time-Domain Feature Extraction

Kim, Kwantae (author), Gao, C. (author), Graca, Rui (author), Kiselev, Ilya (author), Yoo, Hoi Jun (author), Delbruck, Tobi (author), Liu, Shih Chii (author)

This article presents the first keyword spotting (KWS) IC that uses a ring-oscillator-based time-domain processing technique for its analog feature extractor (FEx). Its extensive usage of time-encoding schemes allows the analog audio signal to be processed in a fully time-domain manner except for the voltage-to-time conversion stage of the...

journal article 2022

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Microwave heating mechanism and self-healing performance of asphalt mixture with basalt and limestone aggregates

Wang, Fu (author), Zhu, Hongbin (author), Shu, Benan (author), Li, Yuanyuan (author), Gu, Dengjun (author), Gao, Y. (author), Chen, Anqi (author), Feng, Jianlin (author), Wu, Shaopeng (author)

Traditional asphalt mixtures can't absorb microwave energy efficiently, which limits the development of microwave heating technology in the field of road maintenance. Based on the microwave heating characteristics of basalt aggregates, the overall microwave self-healing rate of the asphalt mixture can be enhanced. The basalt was tested by XRF,...

journal article 2022

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Morphological wave attenuation of the nature-based flood defense: A case study from Chongming Dongtan Shoal, China

Mi, Jie (author), Zhang, Min (author), Zhu, Zhenchang (author), Vuik, V. (author), Wen, Jiahong (author), Gao, Hongkai (author), Bouma, Tjeerd J. (author)

The risk of coastal storm flooding is deteriorating under global warming, especially for the heavily urbanized deltaic cities, like Shanghai. The Nature-Based Flood Defense (NBFD), as an eco-friendly design alternative for hard infrastructure against coastal flooding, is gaining attention. Nevertheless, the vulnerability of saltmarsh due to...

journal article 2022

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Frequency division multiplexing readout of a transition edge sensor bolometer array with microstrip-type electrical bias lines

Wang, Q. (author), Khosropanah, P. (author), Van Der Kuur, J. (author), de Lange, G. (author), Audley, M. D. (author), Aminaei, A. (author), Ilyas, S. (author), van der Tak, F.M. (author), Gao, J.R. (author)

We demonstrate multiplexed readout of 43 transition edge sensor (TES) bolometers operating at 90 mK using a frequency division multiplexing (FDM) readout chain with bias frequencies ranging from 1 to 3.5 MHz and a typical frequency spacing of 32 kHz. We improve the previously reported performance of our FDM system by two important steps....

journal article 2022

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A theoretical study of atmospheric pollutant NO₂ on as-doped monolayer WS₂ based on DFT method

Hou, Shuhan (author), Wang, Zhaokun (author), Yang, Huiru (author), Jiang, Jing (author), Gao, Chenshan (author), Liu, Yufei (author), Tang, Xiaosheng (author), Ye, H. (author)

For the relevant properties of pristine and doped (Si, P, Se, Te, As) monolayer WS₂ before and after the adsorption of CO, CO₂, N₂, NO, NO₂ and O₂, density functional theory (DFT) calculations are made. Calculation results reveal that the monolayer WS₂ doped with P and As atoms...

journal article 2022

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Carbon Dots Embedded in Cellulose Film: Programmable, Performance-Tunable, and Large-Scale Subtle Fluorescent Patterning by in Situ Laser Writing

Guo, Yuanyuan (author), Wang, Quan (author), LI, H. (author), Gao, Yixun (author), Xu, Xuezhu (author), Tang, Biao (author), Yang, B. (author), Lee, Yi Kuen (author), French, P.J. (author)

Fluorescent patterns with multiple functions enable high-security anti-counterfeiting labels. Complex material synthesis and patterning processes limit the application of multifunctional fluorescent patterns, so the technology of in situ fluorescent patterning with tunable multimodal capabilities is becoming more necessary. In this work, an...

journal article 2022

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A Novel Bilevel False Data Injection Attack Model Based on Pre-and Post-Dispatch

Gao, Shibin (author), Lei, Jieyu (author), Wei, Xiaoguang (author), Liu, Y. (author), Wang, Tao (author)

This letter develops a new bilevel optimization model to construct false data injection attack based on pre- and post- dispatch. In order to enhance the attack concealment, the proposed bilevel model can minimize the variation of uploaded measurements between pre- and post-attack before dispatching, after which the attack can lead the system...

journal article 2022

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Strain-engineered S-HfSe₂ monolayer as a promising gas sensor for detecting NH₃: A first-principles study

Yang, Huiru (author), Li, Junfeng (author), Shao, Ziyuan (author), Tan, C. (author), Gao, Chenshan (author), Cui, Hongyuan (author), Tang, Xiaosheng (author), Liu, Yufei (author), Zhang, Kouchi (author), Ye, H. (author)

The development of high-performance gas sensing materials is one of the development trends of new gas sensor technology. In this work, in order to predict the gas-sensitive characteristics of HfSe₂ and its potential as a gas-sensitive material, the interactions of nonmetallic element (O, S, Te) doped HfSe₂ monolayer and...

journal article 2022

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Carbon-Iron Electron Transport Channels in Porphyrin–Graphene Complex for ppb-Level Room Temperature NO Gas Sensing

Gao, Yixun (author), Wang, Jianqiang (author), Feng, Yancong (author), Cao, Nengjie (author), Li, Hao (author), de Rooij, Nicolaas Frans (author), Umar, Ahmad (author), French, P.J. (author), Wang, Yao (author), Zhou, Guofu (author)

It is a great challenge to develop efficient room-temperature sensing materials and sensors for nitric oxide (NO) gas, which is a biomarker molecule used in the monitoring of inflammatory respiratory diseases. Herein, Hemin (Fe (III)-protoporphyrin IX) is introduced into the nitrogen-doped reduced graphene oxide (N-rGO) to obtain a novel...

journal article 2022