document

Terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer

Gao, J.R. (author), Hovenier, J.N. (author), Yang, Z.Q. (author), Baselmans, J.J.A. (author), Baryshev, A. (author), Hajenius, M. (author), Klapwijk, T.M. (author), Adam, A.J.L. (author), Klaassen, T.O. (author), Williams, B.S. (author), Kumar, S. (author), Hu, Q. (author), Reno, J.L. (author)

We report the first demonstration of an all solid-state heterodyne receiver that can be used for high-resolution spectroscopy above 2?THz suitable for space-based observatories. The receiver uses a NbN superconducting hot-electron bolometer as mixer and a quantum cascade laser operating at 2.8?THz as local oscillator. We measure a double...

journal article 2005

document

Reduced noise in NbN hot-electron bolometer mixers by annealing

Yang, Z.Q. (author), Hajenius, M. (author), Baselmans, J.J.A. (author), Gao, J.R. (author), Voronov, B. (author), Gol'tsman, G.N. (author)

journal article 2006

document

Full characterization and analysis of a terahertz heterodyne receiver based on a NbN hot electron bolometer

Hajenius, M. (author), Baselmans, J.J.A. (author), Baryshev, A. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Kooi, J.W. (author), Jellema, W. (author), Yang, Z.Q. (author)

We present a complete experimental characterization of a quasioptical twin-slot antenna coupled small area (1.0×0.15??m2) NbN hot electron bolometer (HEB) mixer compatible with currently available solid state tunable local oscillator (LO) sources. The required LO power absorbed in the HEB is analyzed in detail and equals only 25?nW. Due to the...

journal article 2006

document

Combined Effects of Unsteady River Discharges and Wave Conditions on River Mouth Bar Morphodynamics

Gao, Weilun (author), Shao, Dongdong (author), Wang, Zhengbing (author), Nardin, William (author), Yang, Wei (author), Sun, Tao (author), Cui, Baoshan (author)

River mouth bar formation, a key process in fluvial-deltaic morphodynamics, is subject to both river discharge and waves. Given the increasing variability of both forcings under continuous climate change and human interventions, assessing their combined effects on mouth bar formatio n is an imperative issue. In this study, an extensive set of...

journal article 2018

document

Long-Term Cumulative Effects of Intra-Annual Variability of Unsteady River Discharge on the Progradation of Delta Lobes: A Modeling Perspective

Gao, Weilun (author), Shao, Dongdong (author), Wang, Zhengbing (author), Nardin, William (author), Rajput, Prateek (author), Yang, Wei (author), Sun, Tao (author), Cui, Baoshan (author)

Rivers, regardless of their scales and geographic locations, are characterized with natural and human-induced variability in their discharges. While previous studies have established the effects of both interannual and intra-annual variabilities of unsteady river discharge on delta morphological evolution, the long-term cumulative effects of...

journal article 2019

document

A contactless measuring speed system of belt conveyor based on machine vision and machine learning

Gao, Yuan (author), Qiao, Tiezhu (author), Zhang, Haitao (author), Yang, Yi (author), Pang, Y. (author), Wei, Hongyan (author)

During the operation of the belt conveyor, measuring speed of the belt conveyor is vital to the safe and efficient operation. In the existing measuring speed system, the measurement instrument is required contacting with the surface of the belt. The contact measurement method cannot avoid the occurrence of measuring error caused by slipping...

journal article 2019

document

Room temperature ppt-level NO₂ gas sensor based on SnO _x/SnS nanostructures with rich oxygen vacancies

Tang, H. (author), Gao, Chenshan (author), Yang, Huiru (author), Sacco, L.N. (author), Sokolovskij, R. (author), Ye, H. (author), Vollebregt, S. (author), Fan, X. (author), Zhang, Kouchi (author)

In this paper, tin oxidation (SnO x )/tin-sulfide (SnS) heterostructures are synthesized by the post-oxidation of liquid-phase exfoliated SnS nanosheets in air. We comparatively analyzed the NO2 gas response of samples with different oxidation levels to study the gas sensing mechanisms. The results show that the samples oxidized at 325 °C are...

journal article 2021

document

New innovations in pavement materials and engineering: A review on pavement engineering research 2021

Chen, Jiaqi (author), Dan, Hancheng (author), Ding, Yongjie (author), Gao, Y. (author), Guo, Meng (author), Guo, Shuaicheng (author), Han, Bingye (author), Hong, Bin (author), Hou, Yue (author), Hu, Chichun (author), Hu, Jing (author), Huyan, Ju (author), Jiang, Jiwang (author), Jiang, Wei (author), Li, Cheng (author), Liu, Pengfei (author), Liu, Yu (author), Liu, Zhuangzhuang (author), Lu, Guoyang (author), Ouyang, Jian (author), Qu, Xin (author), Ren, Dongya (author), Wang, Chao (author), Wang, Chaohui (author), Wang, Dawei (author), Wang, Di (author), Wang, Hainian (author), Wang, Haopeng (author), Xiao, Yue (author), Xing, Chao (author), Xu, Huining (author), Yan, Yu (author), Yang, Xu (author), You, Lingyun (author), You, Zhanping (author), Yu, Bin (author), Yu, Huayang (author), Yu, Huanan (author), Zhang, Henglong (author), Zhang, Jizhe (author), Zhou, Changhong (author), Zhou, Changjun (author), Zhu, Xingyi (author)

Sustainable and resilient pavement infrastructure is critical for current economic and environmental challenges. In the past 10 years, the pavement infrastructure strongly supports the rapid development of the global social economy. New theories, new methods, new technologies and new materials related to pavement engineering are emerging....

review 2021

document

Modification on the chloride binding capacity of alkali activated slag by applying calcium and aluminium containing phases

Yang, Tingli (author), Fan, Xiaochun (author), Gao, Xu (author), Gu, Qian (author), Xu, S. (author), Shui, Zhonghe (author)

In this study, a modified alkali activated slag system is designed by introducing additional calcium and aluminum containing phases in the binder, aiming at promote the formation of Friedel's salt (Fs) within the reaction products and therefore achieve a better chloride binding capacity. The effect of calcium and alumina contents on phase...

journal article 2022

document

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

document

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

document

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

document

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

document

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

document

Effect of pretreated cow dung fiber on rheological and fatigue properties of asphalt binder

Niu, D. (author), Zhang, Zhao (author), Gao, Y. (author), Li, Yuanxiao (author), Yang, Zhengxian (author), Niu, Yanhui (author)

Cow dung waste has caused severe environmental pollution and public health issues in China. In this study, the cow dung residues were used as a cheap renewable fiber to modify asphalt binder, providing a new solution for the proper disposal of cow dung waste. Three cow dung fibers with two lengths were prepared using different treatments,...

journal article 2023

document

Investigation on the technical performance and workability of hot-melting road marking materials using for the high-altitude area

Lu, Jing (author), Zhang, Min (author), Feng, Jianlin (author), Gao, Y. (author), Yang, Ye (author), Li, Yuanyuan (author), Li, Linglin (author)

The special environment conditions in high altitude areas leads to serious cracking and peeling of road hot-melt marking coatings. In order to improve the durability of marking paint, a durable hot-melt marking paint was designed by modifying the paint with toughening-agent, rheological agent, and anti-aging agent. The modification mechanism...

journal article 2023

document

Structure and dynamics of urban freight truck movements: A complex network theory perspective

Yang, Y. (author), Jia, Bin (author), Yan, Xiao Yong (author), Chen, Y. (author), Tavasszy, Lorant (author), de Bok, M.A. (author), Bai, Zhuotong (author), Liu, Erjian (author), Gao, Ziyou (author)

Knowledge of the core structure and inherent dynamics of urban freight transport systems is important for the development of policies, aimed at improving the livability and sustainability of cities. The past decade has witnessed a great deal of efforts into analyzing the geographic structure of urban freight transport systems. However, in...

journal article 2023

document

Stretchable strain sensor based on HfSe₂/LIG composite with high sensitivity and good linearity within a wide range

Yang, Huiru (author), Wang, S. (author), Huang, Qianming (author), Tan, C. (author), Gao, Chenshan (author), Xu, Siyuan (author), Ye, Huaiyu (author), Zhang, Kouchi (author)

Flexible strain sensors based on nanomaterials have sparked a lot of interest in the field of wearable smart electronics. Laser induced graphene (LIG) based sensors in particular stand out due to their straightforward fabrication procedure, three-dimensional porous structures, and exceptional electromechanical capabilities. Recent studies...

journal article 2023

document

Slight Multielement Doping-Induced Structural Order-Disorder Transition for High-Performance Layered Na-Ion Oxide Cathodes

Guo, Hao (author), Zhao, C. (author), Gao, Jianxiang (author), Yang, Wenyun (author), Hu, Xufeng (author), Ma, Xiaobai (author), Jiao, Xuesheng (author), Yang, Jinbo (author), Sun, Kai (author), Chen, Dongfeng (author)

To realize concurrently the high-energy density and excellent cycling stability, maximum utilization of redox couple, minimization of detrimental phase transition, and structural degradation of O3-type layered oxide cathodes are critical for developing Na-ion batteries. Ni²⁺/Ni⁴⁺ redox couple showing multielectron...

journal article 2023

document

Rapid extraction of pavement aggregate gradation based on point clouds using deep learning networks

Chen, Siyu (author), Chen, Can (author), Ma, Tao (author), Han, Chengjia (author), Luo, Haoyuan (author), Wang, Siqi (author), Gao, Y. (author), Yang, Yaowen (author)

Usage of asphalt mixture with poor gradation will most likely lead to pavement deficiency. There is a growing need for rapid and non-destructive methods to extract pavement aggregate gradation. In this study, a deep learning-based method that utilizes point clouds data for gradation extraction was proposed. Firstly, a data enhancement...

journal article 2023