504 results on '"Fan, Yang"'
Search Results
2. Atomic layer deposition in advanced display technologies: from photoluminescence to encapsulation
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Rong Chen, Kun Cao, Yanwei Wen, Fan Yang, Jian Wang, Xiao Liu, and Bin Shan
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atomic layer deposition ,display ,luminescent ,encapsulation ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Industrial engineering. Management engineering ,T55.4-60.8 ,Physics ,QC1-999 - Abstract
Driven by the growing demand for next-generation displays, the development of advanced luminescent materials with exceptional photoelectric properties is rapidly accelerating, with such materials including quantum dots and phosphors, etc. Nevertheless, the primary challenge preventing the practical application of these luminescent materials lies in meeting the required durability standards. Atomic layer deposition (ALD) has, therefore, been employed to stabilize luminescent materials, and as a result, flexible display devices have been fabricated through material modification, surface and interface engineering, encapsulation, cross-scale manufacturing, and simulations. In addition, the appropriate equipment has been developed for both spatial ALD and fluidized ALD to satisfy the low-cost, high-efficiency, and high-reliability manufacturing requirements. This strategic approach establishes the groundwork for the development of ultra-stable luminescent materials, highly efficient light-emitting diodes (LEDs), and thin-film packaging. Ultimately, this significantly enhances their potential applicability in LED illumination and backlighted displays, marking a notable advancement in the display industry.
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- 2024
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3. A parallel quantum eigensolver for quantum machine learning
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Fan Yang, Dafa Zhao, Chao Wei, Xinyu Chen, Shijie Wei, Hefeng Wang, Guilu Long, and Tao Xin
- Subjects
eigensolver ,quantum computing ,recommendation system ,Science ,Physics ,QC1-999 - Abstract
Eigensolvers have a wide range of applications in machine learning. Quantum eigensolvers have been developed for achieving quantum speedup. Here, we propose a parallel quantum eigensolver (PQE) for solving a set of machine learning problems, which is based on quantum multi-resonant transitions that simultaneously trigger multiple energy transitions in the systems on demand. PQE has a polylogarithmic cost in problem size under certain circumstances and is hardware efficient, such that it is implementable in near-term quantum computers. As a verification, we utilize it to construct a collaborative filtering quantum recommendation system and implement an experiment of the movie recommendation tasks on a nuclear spin quantum processor. As a result, our recommendation system accurately suggests movies to the user that he/she might be interested in. We further demonstrate the applications of PQE in classification and image completion. In the future, our work will shed light on more applications in quantum machine learning.
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- 2024
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4. Effects of electrical pulse on metal deformation behaviors
- Author
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Tao Huang, Fan Yang, Bing-Hui Xing, Ke-Xing Song, Nan Xiang, Yan-Min Zhang, Xue-Wen Chen, and Jun-Qing Guo
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electrically assisted forming ,prediction model ,flow stress ,microstructure ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
As a kind of special energy field assisted plastic forming, electric pulse assisted plastic forming combines multiple physical fields, such as thermal, electrical, magnetic and mechanical effects, has multiple effects on metal. It has a good industrial application prospect in the fields of directional microstructure regulation of materials and preparation of new materials. The flow stress of metal materials can be effectively reduced by electro-pulse assisted forming. The action mechanism of pulse current includes thermodynamics (Joule heating effect) and kinetic (pure electro-plastic effect or athermal effect). Thermodynamically, electric pulses can be used to provide the energy for dislocation migration and atomic diffusion, and aid in microstructure changes such as recrystallization, phase transition and microcrack healing of metals. In terms of dynamics, electric pulse has an effect on the speed and path of dislocation structure evolution. On this basis, a series of theoretical models for accurately predicting the flow stress of materials in electrically assisted forming process were formulated by combining the stress–strain constitutive relationship considering the temperature rise effect and the pure electro-plastic effect. The accuracy of the predicting model is greatly enhanced by the introduction of electrical parameters. The mechanism for electrically assisted forming was further revealed.
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- 2024
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5. A noise-robust quantum dynamics learning protocol based on Choi–Jamiolkowski isomorphism: theory and experiment
- Author
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Xin-Yu Chen, Pan Gao, Chu-Dan Qiu, Ya-Nan Lu, Fan Yang, Yuanyuan Zhao, Hang Li, Jiang Zhang, Shijie Wei, Tonghao Xing, Xin-Yu Pan, Dong Ruan, Feihao Zhang, Keren Li, and Guilu Long
- Subjects
indirect learning ,Choi–Jamiolkowski isomorphism ,noise resilience ,nitrogen-vacancy center ,Science ,Physics ,QC1-999 - Abstract
With the rapid development of quantum technology, the growing manipulated Hilbert space makes learning the dynamics of the quantum system a significant challenge. Machine learning technique has brought apparent advantages in some learning strategies, therefore, we introduce it to indirect learning in this paper. Based on Choi–Jamiolkowski isomorphism, we propose a protocol that learns the dynamics of an inaccessible quantum system using a quantum device at hand. For an n -qubit system, the learning task can be done iteratively, with operational complexity $\mathcal{O}(\text{poly}(n, L)/\epsilon^2)$ in each iteration, where L is the circuit depth and ε is the measurement error. Then we theoretically prove its noise resilience to global depolarization, state preparation and measurement noise, and unitary noise in gates implementation, where we find the learned dynamics stay invariant. Finally, we investigate the protocol experimentally on a nitrogen-vacancy center system with a natural noise source. The results show that the behavior of a relatively intractable nuclear spin can be learned through an easily accessible electron spin under different noise models, demonstrating the protocol’s feasibility.
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- 2024
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6. Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture
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Mingjun Zhang, Liang Li, Fan Yang, Shigang Zhang, He Zhang, and Jian An
- Subjects
high alumina coal gangue ,kaolinite ,thermal activation ,mechanical properties ,microstructure ,cementitious admixture ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
In order to use high alumina coal gangue as auxiliary cementitious admixture via a simple and convenient thermal activation technique, the thermal transformation, mineral phase transformation and structure changes of coal gangue at calcining temperatures of 500–1000 °C were analyzed using x-ray diffraction (XRD), differential thermal Analysis (DTA), thermogravimetry (TG), infrared analysis (IR) and scanning electron microscope (SEM). The mechanical properties of cement mortar with 30% coal gangue auxiliary cementitious admixture were also measured to determine the optimal calcining temperature. As calcining temperature was increased, the coal gangue experienced the following transformations: carbon combustion, dehydroxylation, metakaolin transformation and mullite transformation. The cement mortar with coal gangue auxiliary cementitious admixture calcined at 700 °C presented the highest 28-d flexural and compressive strength, increasing by 8.27% and 11.85% respectively as compared with the benchmark cement mortar. The maximum dosage of coal gangue auxiliary cementitious admixture in cement mortar was further identified to be less than 30% by mechanical properties testing. The activity of high alumina coal gangues at different calcining temperatures was explained from the view points of hydration degree and products. The present investigation can provide a useful reference to utilize high alumina coal gangue as auxiliary cementitious admixture by means of a simple thermal activation at 700 °C.
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- 2024
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7. Experimental simulation of quantum superchannels
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Hang Li, Kai Wang, Shijie Wei, Fan Yang, Xinyu Chen, Barry C Sanders, Dong-Sheng Wang, and Gui-Lu Long
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quantum channels ,quantum superchannels ,quantum simulation ,nuclear magnetic resonance ,NMR ,Science ,Physics ,QC1-999 - Abstract
Simulating quantum physical processes has been one of the major motivations for quantum information science. Quantum channels, which are completely positive and trace preserving processes, are the standard mathematical language to describe quantum evolution, while in recent years quantum superchannels have emerged as the substantial extension. Superchannels capture effects of quantum memory and non-Markovianality more precisely, and have found broad applications in universal models, algorithm, metrology, discrimination tasks, as examples. Here, we report an experimental simulation of qubit superchannels in a nuclear magnetic resonance (NMR) system with high accuracy, based on a recently developed quantum algorithm for superchannel simulation. Our algorithm applies to arbitrary target superchannels, and our experiment shows the high quality of NMR simulators for near-term usage. Our approach can also be adapted to other experimental systems and demonstrates prospects for more applications of superchannels.
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- 2024
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8. Functional nanolayers favor the stability of solid-electrolyte-interphase in rechargeable batteries
- Author
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Liu, Huiqiao, primary, Zhang, Jiakun, additional, Fu, Jinjin, additional, Li, Chao, additional, Fan, Yang, additional, and Cao, Kangzhe, additional
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- 2024
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9. High-Temperature Reliability of Nano-Ag Sintered Joints on Ag-Plated Cu Substrates
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Xiaoting, Wang, primary, He, Jingjing, additional, Peng, Zhipeng, additional, Fan, Yang, additional, and Wenbo, Zhu, additional
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- 2024
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10. Combinatorial development of antibacterial FeCoCr-Ag medium entropy alloy
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Jiashu Cao, Xin Jiang, Qinghua Zhang, Fusen Yuan, Jihao Yu, Fan Yang, Mingxing Li, Chao Wang, Ying Lu, Ming Li, Weihua Wang, and Yanhui Liu
- Subjects
antibacterial metals and alloys ,medium entropy alloy ,combinatorial method ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Antibacterial activity and mechanical properties of FeCoCr-Ag medium entropy alloys were studied via combinatorial fabrication paired with high-throughput characterizations. It was found that the antibacterial activity and mechanical properties exhibit non-linear dependence on the content of Ag addition. Within the studied alloys, (FeCoCr) _80 Ag _20 possesses an optimized combination of different properties for potential applications as antibacterial coating materials. The underlying mechanism is ascribed to the formation of a dual-phase structure that leads to competition between the role of Ag phase and FeCoCr phase at different Ag content. The results not only demonstrate the power and effectiveness of combinatorial methods in multi-parameter optimization but also indicate the potential of high entropy alloys as antibacterial materials.
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- 2023
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11. TESS Timings of 31 Hot Jupiters with Ephemeris Uncertainties
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Su-Su Shan, Fan Yang, You-Jun Lu, Xing Wei, Wen-Wu Tian, Hai-Yan Zhang, Rui Guo, Xiao-Hong Cui, Ai-Yuan Yang, Bo Zhang, and Ji-Feng Liu
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Exoplanet astronomy ,Exoplanet systems ,Transit photometry ,Transit timing variation method ,Astrophysics ,QB460-466 - Abstract
A precise transit ephemeris serves as the premise for follow-up exoplanet observations. We compare TESS Object of Interest (TOI) transit timings of 262 hot Jupiters with the archival ephemeris and find 31 of them having TOI timing offsets, among which WASP-161b shows the most significant offset of −203.7 ± 4.1 minutes. The median value of these offsets is 17.8 minutes, equivalent to 3.6 σ . We generate TESS timings in each sector for these 31 hot Jupiters, using a self-generated pipeline. The pipeline performs photometric measurements to TESS images and produces transit timings by fitting the light curves. We refine and update the previous ephemeris, based on these TESS timings (uncertainty ∼1 minute) and a long timing baseline (∼10 yr). Our refined ephemeris gives the transit timing at a median precision of 0.82 minutes until 2025 and 1.21 minutes until 2030. We regard the timing offsets to mainly originate from the underestimated ephemeris uncertainty. All the targets with timing offset larger than 10 σ present earlier timings than the prediction, which cannot be due to underestimated ephemeris uncertainty, apsidal precision, or Rømer effect as those effects should be unsigned. For some particular targets, timing offsets are likely due to tidal dissipation. Our sample leads to the detection of period-decaying candidates of WASP-161b and XO-3b reported previously.
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- 2023
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12. Low-temperature ferromagnetism in tensile-strained LaCoO2.5 thin film
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Fan, Yang-Yang, primary, Wang, Jing, additional, Hu, Feng-Xia, additional, Li, Bao-He, additional, Geng, Ai-Cong, additional, Yin, Zhuo, additional, Zhang, Cheng, additional, Zhou, Hou-Bo, additional, Wang, Meng-Qin, additional, Yu, Zi-Bing, additional, and Shen, Bao-Gen, additional
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- 2023
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13. Mottness induced superfluid phase fluctuation with increased density
- Author
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Zi-Jian Lang, Fan Yang, and Wei Ku
- Subjects
superfluid phase stiffness ,phase fluctuation ,Gutzwiller approximation ,Science ,Physics ,QC1-999 - Abstract
Recent observation of diminishing superfluid phase stiffness upon increasing carrier density in cuprate high-temperature superconductors is unexpected from the quantum density-phase conjugation of superfluidity. Here, through analytic estimation and verified via variational Monte Carlo calculation of an emergent Bose liquid, we point out that Mottness of the underlying carriers can cause a stronger phase fluctuation of the superfluid with increasing carrier density. This effect turns the expected density-increased phase stiffness into a dome shape, in good agreement with the recent observation. Specifically, the effective mass divergence due to ‘jamming’ of the low-energy bosons reproduces the observed nonlinear relation between phase stiffness and transition temperature. Our results suggest a new paradigm, in which unconventional superconductivity in some strongly correlated materials is described by physics of bosonic superfluidity, as opposed to pairing-strength limited Cooper pairing.
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- 2022
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14. Ultra-thin foldable transparent electrodes composed of stacked silver nanowires embedded in polydimethylsiloxane
- Author
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Xingzhen Yan, Bo Li, Kaian Song, Fan Yang, Yanjie Wang, Chao Wang, Yaodan Chi, and Xiaotian Yang
- Subjects
silver nanowire ,coating ,freeform substrate ,folding ,transparent electrode ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
We have prepared an ultra-thin flexible transparent conductive electrode with high folding endurance composed of randomly arranged silver nanowires (AgNWs) embedded in polydimethylsiloxane (PDMS). A simple preparation method was performed to connect a glass substrate coated with a AgNW network and a glass substrate coated with PDMS. The glass substrate was then removed after the PDMS solidified, and the AgNW–PDMS composite film was peeled off. Moreover, the problem of the high contact resistance caused by the random arrangement of AgNWs was solved by the local joule heat generated by applying voltage to both sides of the AgNW–PDMS composite structure to weld the overlapping AgNWs. The sheet resistance ( R _s ) of AgNW–PDMS composite films with different AgNW deposition concentrations decreased by 46.4%–75.8% through this electro-sintering treatment. The embedded structure of the AgNW–PDMS composite ensures better voltage resistance and environmental stability under high temperature and humidity conditions compared with a AgNW network attached to a glass substrate. Additionally, the substrate-free, excellent elasticity and high resilience characteristics resulted in the R _s value of the same composite electrode only increasing by 2.9 ohm sq ^−1 after folding four times. The advantage of the metal thermal conductivity makes the joule heat generated by electric injection rapidly diffuse and dissipate in the AgNW-based transparent heater with faster response time and smaller voltage drive than indium tin oxide.
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- 2022
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15. A feasible strategy of fabricating camptothecin (SN38)-loaded holmium ferrite nanocarrier delivery for glioma treatment
- Author
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Yu Zeng, Huihui Chen, Fan Yang, Huiyong Li, and Pengxiang Yang
- Subjects
biocompatibility ,holmium ferrite ,cytotoxicity ,glioma cancer ,SN38 ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
Malignant gliomas are the most prevalent and deadly primary brain tumors. The life expectancy of people with gliomas only slightly increases through surgical procedures, radiation, and chemotherapy. Magnetic nanocarriers must be developed to enable drug delivery using a magnetic field. A utilized to fabricate holmium ferrite nanoparticles is described herein. β -Cyclodextrin-polyethylene glycol (PEG) conjugate is used as a coat for the holmium ferrite nanoparticles. X-ray diffraction, energy dispersive x-ray spectroscopy, and x-ray photoelectron spectroscopy are all used to study the nanoparticles. This size range of nanoparticles is optimal for efficient drug delivery. The in vitro cytotoxicity of the fabricated nanoparticles was examined using U87MG and LN229 glioma cancer cells. The acridine orange/ethidium bromide and nuclear staining methods examined the morphological changes in the U87MG and LN229 glioma cells. The mode of cell death mechanism was investigated by Annexin V-FITC/PI flow cytometry methods. The possibility for successful SN38 delivery for the treatment of glioma cancer exists with the SN38@HF- β -CD-PEG.
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- 2022
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16. Study on Selection of Test Water for the Large Liquefied Natural Gas (LNG) Storage Tanks
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Fan, Yang, primary, Li, Xiao, additional, Yuqi, Zhang, additional, and Huan, Huang, additional
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- 2023
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17. High-Temperature Reliability of Nano-Ag Sintered Joints on Ag-Plated Cu Substrates.
- Author
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Xiaoting, Wang, He, Jingjing, Peng, Zhipeng, Fan, Yang, and Wenbo, Zhu
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- 2023
- Full Text
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18. Impact load identification and localization method on thin-walled cylinders using machine learning
- Author
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Chenyu Guo, Liangliang Jiang, Fan Yang, Zhiguang Yang, and Xi Zhang
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Mechanics of Materials ,Signal Processing ,General Materials Science ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Civil and Structural Engineering - Abstract
In this paper, a novel impact load identification and localization method on actual engineering structures using machine learning is proposed. Three machine learning models, including a gradient boosting decision tree (GBDT) model based on ensemble learning, a convolutional neural network (CNN) model and a bidirectional long short-term memory (BLSTM) model based on deep learning, are trained to directly identify and locate impact loads according to dynamic response. The GBDT model and the CNN model can reversely identify force peak and location of impact loads. The BLSTM model can reconstruct the time history of impact loads. The method is verified on a thin-walled cylinder with obvious nonlinearity. The result shows that the method can accurately identify impact loads and its location. The characteristics of the three models are compared and the influence of structural boundary conditions on the accuracy of identification is discussed. The proposed method has the potential to be applied to various engineering structures and multiple load types.
- Published
- 2023
19. A novel inchworm piezoelectric actuator using two-stage amplification mechanism with high speed: design, modeling, and experimental evaluation
- Author
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Simiao Yu, JiaYu Liang, Fan Yang, Haitao Wang, Xianglong Liu, Chao Xu, Zhen Wang, and Dongmei Xu
- Subjects
Mechanics of Materials ,Signal Processing ,General Materials Science ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Civil and Structural Engineering - Abstract
The inchworm piezoelectric actuator has a wide application prospect in the field of precision instruments. However, in view of the complex structure of the existing inchworm piezoelectric actuator and the far distance between the driving feet of the actuator, it is difficult to realize alternate driving and the high output speed of the driving feet, etc. In this paper, an inchworm piezoelectric linear actuator based on two-stage amplification mechanism is designed, which amplifies the output displacement of the driving feet by two-stage amplification mechanism, and improves the driving efficiency of the actuator stator by the way of alternating driving. We present an inchworm piezoelectric actuator with three piezoelectric stacks and a two-stage amplification mechanism, which is simple in structure design, compact in actuator structure and easy to realize alternate driving. The kinematics and dynamics models of the inchworm piezoelectric actuator are established by analyzing the flexible hinge and its structure with the pseudo-rigid body method. The length of the lever structure and the angle of the triangular structure of the piezoelectric actuator are solved by kinematics, and the natural frequency of the whole structure is calculated by dynamics. Through finite element analysis, the simulation magnification ratio of the piezoelectric actuator is obtained, so as to evaluate and verify the theoretical calculation and further optimize the structure. The experimental results show that the inchworm piezoelectric linear actuator using two-stage amplification mechanism has a high driving speed of 5.53 mm s−1 under voltage of 135 V and frequency of 70 Hz.
- Published
- 2023
20. Research on Distributed Measurement and Control System Based on FlexRay Bus
- Author
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Xiaodong Zhao, Fan Yang, Wantong Li, and Haiyuan Li
- Subjects
History ,Computer Science Applications ,Education - Abstract
With the purpose of the design problem of electromagnetic launch distributed measurement and control system, this paper proposes a design method of scalable large-scale distributed interconnected measurement and control system based on FlexRay bus. The task execution time deviation of each node in the distributed system, including phase deviation and frequency deviation, is reduced by using the macro tick generation process and clock synchronization process to achieve task synchronization in the distributed system. The synchronization of timing generation is realized based on the universal clock technology. When the timing interval is zero, the pulse power units are guaranteed to be close to the ideal full synchronization, thus ensuring that the released energy during transmission is close to the design value. In the state of adjustable timing, when the pulse power supply module conducts pulse discharge, the trigger discharge times of the modules are set according to the load needs. The flat top, sawtooth, and other characteristic current waveforms are adjusted accurately. At the same time, a combined multi-level protection structure based on hardware and software is realized. The verification results show that the distributed electromagnetic launch measurement and control system implemented in this paper can meet the high efficiency, fast and continuous launch target.
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- 2023
21. Measurements of Majorana transition frequency shift in caesium atomic fountain clocks
- Author
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Jun-Ru Shi, Xin-Liang Wang, Fan Yang, Yang Bai, Yong Guan, Si-Chen Fan, Dan-Dan Liu, Jun Ruan, and Shou-Gang Zhang
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General Physics and Astronomy - Abstract
The caesium atomic fountain clock is a primary frequency standard. During its operation, a Majorana transition frequency shift will occur once a magnetic field at some special locations along the atomic trajectory is singular. In this study, by developing a physical model, we analyzed the magnetic field requirements for atomic adiabatic transition and calculated the influence of the Majorana atomic transition on the atomic state via a quantum method. Based on the simulation results for the magnetic field in the fountain clock, we applied the Monte Carlo method to simulate the relationship between the Majorana transition frequency shift and the magnetic field at the entrance of the magnetic shielding, as well as the initial atomic population. Measurement of the Majorana transition frequency shift was realized by state-selecting asymmetrically populated atoms. The relationship between the Majorana transition frequency shift and the axial magnetic field at the entrance of the magnetic shielding was obtained. The measured results were essentially consistent with the calculated results. Thus, the magnetic field at the entrance of the magnetic shielding was configured, and the Majorana transition frequency shift of the fountain clock was calculated to be 4.57 × 10−18.
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- 2023
22. Research on Connector Assembly System and Control Strategy for Large-scale Panel
- Author
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Fan, Yang, primary, Changming, Hu, additional, Zhanying, Feng, additional, Min, Liu, additional, and Xumin, Wang, additional
- Published
- 2022
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23. Dynamic morphology imaging of cardiomyocytes based on AFM
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Can Cheng, Xingyue Wang, Jianjun Dong, Fan Yang, Tuoyu Ju, and Zuobin Wang
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Bioengineering ,General Chemistry ,Electrical and Electronic Engineering - Abstract
A cardiomyocyte is the basic structural and functional unit of the heart, which is the actual executor of the systolic function. The study of the contraction and relaxation characteristics of cardiomyocyte is of great significance to the physiological behavior and pathology of the heart. How to dynamically express its contraction and relaxation behaviors in 3D has become a challenging issue. Although the video analysis method under the optical microscope can observe the changes in the horizontal direction, it is difficult to describe the changes in the vertical direction. The atomic force microscope (AFM) can accurately express the mechanical and morphological characteristics of the changes in the vertical direction, but it cannot be fully expressed in real time because it is acquired by scanning with a single probe. In order to express the contraction and relaxation characteristics of cardiomyocyte accurately and three dimensionally, a dynamic imaging method in this study is proposed using the periodicity of AFM acquisition and the periodicity of cardiomyocyte contraction. Compared with the optical experiment, it is proven that this method can dynamically represent the contraction and relaxation processes of cardiomyocyte and solve the problem of how to express it in 3D. It brings a new way for the study of physiological characteristics of cardiomyocytes and dynamic imaging by AFM.
- Published
- 2023
24. Simulation Research for Thermal Characteristics for Temperature Gradient of Three-core Cable Joint
- Author
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Shaohua Wang, Xuxiang Wu, Junping Cao, Ruixiang Tao, Rong Xia, Jian Zhao, Xing Li, and Fan Yang
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History ,Computer Science Applications ,Education - Abstract
Temperature is one of the important parameters of power cables with normal operation. In this article, the electromagnetic and thermal characteristics of three-core cable joints were investigated. And the core and surface temperature gradient were obtained with a three-core cable joint. The research results show that the core temperature of the center is about higher than 14 °C than the body part. The surface temperature is distributed as high at the center and low at the body. The surface fluctuation amplitude of the joint center temperature is about 10 °C. The maximum surface temperature gradient with the center can reach 1697 °C/m of cable joint. The results here should have potential application value in characteristics of electromagnetic-thermal coupling field under the action of internal defects of cable joint.
- Published
- 2023
25. Plasmon-enhanced photocatalysis using gold nanoparticles encapsulated in nanoscale molybdenum oxide shell
- Author
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Zizi Tao, Jiyuan Feng, Fan Yang, Liqiu Zhang, Hongxia Shen, Qiong Cheng, and Lichun Liu
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Bioengineering ,General Chemistry ,Electrical and Electronic Engineering - Abstract
Using solar energy to enhance the transformation rate of organic molecules is a promising strategy to advance chemical synthesis and environmental remediation. Plasmonic nanoparticles responsive to sunlight show great promise in the catalysis of chemical reactions. In this work, we used a straightforward wet-chemistry method to synthesize plasmonic octahedral gold nanoparticles (NPs) coated with thin molybdenum oxide (MoO3−x ), Au@MoO3−x NPs, which exhibited strong surface plasmon resonance in a broad wavelength range. The synthesized Au@MoO3−x NPs were characterized by UV–vis, SEM, TEM, EDS, XPS, and the electrochemical technique of cyclic voltammetry (CV). The catalytic performance of Au@MoO3−x NPs under visible light irradiation was investigated using the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) as a model reaction. The presence of a thin capping layer of MoO3−x on our Au NPs contributed to the broadening of their range of absorption of visible light, resulting in a stronger intra-particle plasmonic resonance and the modulation of surface energy and electronic state. Accordingly, the kinetics of plasmon photocatalytic transformation of 4-NP to 4-AP was significantly accelerated (by a factor of 8.1) under visible light, compared to uncapped Au NPs in the dark. Our as-synthesized Au@MoO3−x NPs is an example that the range of plasmonic wavelengths of NPs can be effectively broadened by coating them with another plasmon-active (semiconducting) material, which substantially improves their plasmonic photocatalytic performance. Meanwhile, the synthesized Au@MoO3−x NPs can be used to accelerate the transformation of organic molecules under visible light irradiation.
- Published
- 2023
26. Circuit Breaker Identification Based on SSD
- Author
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Yuhuan Li, Fan Yang, Yan Li, Changshu Tan, and Zijun Liu
- Subjects
History ,Computer Science Applications ,Education - Abstract
The circuit breaker is a device that cuts off and connects the load circuit in the power system, cuts off the fault circuit, prevents the accident from expanding, and ensures safe operation. Detecting circuit breaker failures is necessary to ensure power systems’ safety. Before fault identification, the circuit breaker must be identified and positioned first. In this paper, a circuit breaker identification technology based on SSD is adopted, and SSD is used to identify the circuit breaker and mark the voltage name quickly.
- Published
- 2023
27. Electrical equipment identification method in infrared images based on VGG
- Author
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Yan Li, Jinqiao Du, Lin Zhang, Jie Tian, Fan Yang, and Zhimin Li
- Subjects
History ,Computer Science Applications ,Education - Abstract
Temperature is widely used to detect the state of electric equipment. Almost all the data is collected and sorted. And image analyzed by manual, which cause some trouble. In order to improve the intelligence level of power equipment detection, this paper proposes an infrared scene identification method for 220 kV current transformers, including target identification, temperature extraction, and image fusion. Firstly, a semantic segmentation model is built on VGG, which can effectively extract the target temperature information in complex environments. Then combined with the method of data set expansion, 3224 images of 220 kV current transformers were used for training. Finally, an image fusion method is used to extract equipment temperature. The experimental show that the method proposed in this paper for semantic segmentation and identification of 220 kV current transformers accuracy reaches 99.68%. In contrast, the traditional CNN identification method is 44%, effectively improving the target identification efficiency of 220 kV current transformers and has a good reference for electric equipment intelligence detection.
- Published
- 2023
28. Exponential law for random maps on compact manifolds*
- Author
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Jérôme Rousseau, Fan Yang, and Nicolai Haydn
- Subjects
Pure mathematics ,Applied Mathematics ,Realisation ,010102 general mathematics ,Skew ,General Physics and Astronomy ,Asymptotic distribution ,Statistical and Nonlinear Physics ,Interval (mathematics) ,01 natural sciences ,Exponential function ,010101 applied mathematics ,Product (mathematics) ,0101 mathematics ,Exponential law ,Mathematical Physics ,Unit interval ,Mathematics - Abstract
We consider random dynamical systems on manifolds modelled by a skew product which have certain geometric properties and whose measures satisfy quenched decay of correlations at a sufficient rate. We prove that the limiting distribution for the hitting and return times to geometric balls are both exponential for almost every realisation. We then apply this result to random C 2 maps of the interval, random parabolic maps on the unit interval and random perturbation of partially hyperbolic attractors on a compact Riemannian manifold.
- Published
- 2020
29. Author response for 'Exploring dynamic functional connectivity alterations in the preclinical stage of Alzheimer’s disease: an exploratory study from SILCODE'
- Author
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null Fan Yang, null Xueyan Jiang, null Feng Yue, null Luyao Wang, null Henning Boecker, null Ying Han, and null Jiehui Jiang
- Published
- 2022
30. Balanced Optimization Design of Aluminum Alloy Impeller Rapid Casting Production Line
- Author
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Zheng, Wenqing, primary, Zhang, Siqi, additional, Fan, Yang, additional, Song, Aonan, additional, Li, Bowen, additional, and Lu, Yanqiu, additional
- Published
- 2022
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31. Symbolic regression assisted design of perovskite-type OER electrocatalysts for oxygen evolution reaction (OER) in alkaline electrolyte
- Author
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Wentao Li, Fan Yang, and Junliang Zhang
- Subjects
History ,Computer Science Applications ,Education - Abstract
Perovskite oxides are promising electrocatalysts for oxygen evolution reaction (OER) in alkaline electrolytes. With high activity and low cost, they are being pursued by researchers worldwide. However, due to the compositional and structural diversity of perovskite-type oxides, the conventional method based on experimental trials on thousands of elemental combinations is inefficient and time-consuming, which hampers the development of this type of electrocatalyst. Here we employed a symbolic regression (SR) method under a machine learning framework to build mathematical formulae that best fit datasets based on 105 experimentally studied perovskite-type electrocatalysts and identified a simple parameter as the OER activity descriptor. Results show that B-site cations with a large number of d electrons and a small radius, such as Ni4+, Co4+, and Fe4+, are beneficial to high OER activity in perovskite oxides, which provide a guide for materials design.
- Published
- 2022
32. Research on propagation delay correction method based on scaled model of enhanced Loran transmitting antenna
- Author
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Zhaopeng Hu and Fan Yang
- Subjects
History ,Computer Science Applications ,Education - Abstract
The enhanced Loran signal transmits the signal through the atmospheric channel. Considering the obstacles and other factors, the radio wave will be affected by path loss, shadow fading and multipath fading. Therefore, the signal power at different distances from the transmitting point is different. The scaled model antenna is used to transmit and receive the enhanced Loran signal, and the Loran receiver is used to receive. According to the different power of the received signal of the receiver, the signal propagation distance can be deduced by using the correlation model, so as to correct the path delay, that is, the timing accuracy can be improved.
- Published
- 2022
33. A yaw attitude determination method based on coarse sun sensor information for the GEO satellite
- Author
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Jing Yin, Jiang Liu, and Fan Yang
- Subjects
History ,Computer Science Applications ,Education - Abstract
The coarse sun sensor is used to measure the satellite’s attitude relative to the sun. If the satellite can maintain the earth-pointing attitude by the high-precision sensor, the coarse sun sensor information can be used to determine the satellite’s yaw attitude, which is effective in coping with the short-term failure of the satellite’s yaw attitude sensor. This paper proposes a method to determine the yaw attitude of the satellite using the coarse sun sensor information. In view of the main factors affecting the accuracy of the coarse sun sensor, the measures to improve the yaw accuracy are proposed: the sensor calibration method based on historical data and effective measurement range selection. Simulation with satellite onboard data, the expected function can be achieved, and by correcting the measurement data, the yaw attitude accuracy can be significantly improved.
- Published
- 2022
34. Multi-objective optimization method for distributed energy storage configuration under distribution network operation constraints
- Author
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Wen Long, Bin Zhu, Huaizheng Li, Fan Yang, Wenxin Peng, and Qiang Wang
- Subjects
History ,Computer Science Applications ,Education - Abstract
The multi-objective optimization method for distributed energy storage configuration has the problem of high network loss expectation. A multi-objective optimization method for distributed energy storage configuration under distribution network operation constraints is designed to solve the above problems. The intra-day charge/discharge balance is used as a criterion to identify the characteristics of distributed energy storage configuration, calculate the network loss sensitivity of nodes, construct a siting and capacity setting model, and integrate multiple power quality indicators to improve the multi-objective optimization model under the distribution network operation constraint. The experimental results show that the mean values of network loss expectations for the distributed energy storage configuration multi-objective optimization method in the paper and the other two distributed energy storage configuration multi-objective optimization methods are: 226.731 kW, 270.762 kW, and 276.728 kW, respectively, indicating that the designed distributed energy storage configuration multi-objective optimization method is more feasible after fully considering the distribution network operation constraints.
- Published
- 2022
35. A high dynamic weak spread spectrum signal acquisition strategy based on the transfer model
- Author
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Fan Yang, Zhijun Meng, Guangming Wang, Xiye Guo, Enqi Yan, and Yufeng Zhang
- Subjects
History ,Computer Science Applications ,Education - Abstract
To solve the problem of low Earth orbit (Leo) satellite constellation link spread spectrum signal acquisition in the high dynamic weak environment, this paper proposes a acquisition strategy based on transfer model. In this paper, we analyze the dynamic characteristics of link signal. An improved method of parallel code phase search acquisition based on transfer model acquisition strategy is introduced, the improvement of the proposed acquisition strategy to the traditional acquisition algorithm is illustrated through theoretical analysis. Simulation results verify the superiority of the acquisition strategy based on the transfer model for high dynamic weak signal acquisition.
- Published
- 2022
36. A novel convolutional network with a self-adaptation high-pass filter for fault diagnosis of wind turbine gearboxes
- Author
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Fan Yang, Donghua Huang, Dongdong Li, Yao Zhao, Shunfu Lin, and Muyeen S M
- Subjects
Applied Mathematics ,Instrumentation ,Engineering (miscellaneous) - Abstract
The fault diagnosis of a wind turbine gearbox is helpful for reducing the operating costs and risks of wind power systems. However, existing machine-learning-based gearbox fault diagnosis methods have two shortcomings: (a) data samples of gearbox faults are always scarce; and (b) due to the complex structure of gearboxes, the collected vibration signals often contain a large amount of low-frequency noise, which is detrimental to both feature extraction and fault diagnosis. To solve the above two problems, a combination of deep convolutional generative adversarial networks (DCGANs) and a convolutional network with a high-pass filter (CNHF) is proposed in this paper. Among them, the DCGAN combined with one-dimensional (1D) vibration data converted to a grayscale map is used to expand the fault data to solve the problem of a lack of fault data samples. The CNHF is realized by adding an adaptive high-pass filter to the conventional convolutional layer, and the threshold of the high-pass filter is adaptively set by the 1D convolution according to different data characteristics, thus greatly filtering out the interference of low-frequency noise and realizing the accurate diagnosis of faults. Experiments are performed on a drivetrain dynamics simulator rig to verify the efficacy of the proposed method.
- Published
- 2022
37. A Remote Monitoring and Maintenance System for Industrial Robots
- Author
-
Jian Zhou, Xiao-jian Ding, Li-Jun Sun, Yun-Fan Yang, Yuan-hang Wang, and Wen-Wei Liu
- Subjects
History ,Computer Science Applications ,Education - Abstract
Technologies such as external sensors, data acquisition, trend analysis, and cloud services make remote operation and maintenance of equipment status monitoring more convenient and lower maintenance costs. In this paper, an industrial robot operation and maintenance system is designed. First, the online monitoring of the robot is realized by collecting the control parameters, state parameters, fault information and external sensor monitoring information of the industrial robot. Then, the health baseline of the industrial robot is established based on the historical operation data. The online data is compared with the baseline data to realize the online assessment of the robot’s health status. Finally, a visualization platform for remote operation and maintenance of the robot is built to realize the online display of parameters, health trend tracking and fault status early warning, which is convenient for maintenance personnel to take timely countermeasures.
- Published
- 2022
38. An Ultra-wide Bandwidth Low-frequency Radio Astronomical Cryogenic Receiver for FAST Telescope
- Author
-
Hong-Fei Liu, Peng Jiang, Chuan He, Fan Yang, Hong-Ju Liu, Sheng-Wang Wang, Yang Wu, Yan Zhu, Yang Cao, Jin-You Song, Xiang-Wei Shi, Ming-Lei Guo, Hang Zhang, and Wen-Hao Liu
- Subjects
Space and Planetary Science ,Astronomy and Astrophysics - Abstract
This paper presents an ultra-wide bandwidth (UWB) low-frequency radio astronomical cryogenic receiver for the Five-hundred-meter Aperture Spherical radio Telescope (FAST). It covers 6.6:1 bandwidth from 0.5 to 3.3 GHz. The receiver consists of a Quad-Ridged Flared Horn (QRFH), a cryogenic microwave unit, an optical transceiver and a warm microwave and frequency mixing unit. A QRFH with a concentric-loaded dielectric spear is developed: the average return losses are larger than 20 dB; the average ports polarization isolation is 43.87 dB; the average dish efficiency is higher than 65%. Many UWB cryogenic low loss components are developed for the fabrication of a cryogenic microwave unit. The average noise temperature lower than 14.2 K and 22.5 K are achieved as referred to the input ports of cryogenic Dewar and the output of horn, respectively. Compared to other similar advanced UWB receivers, such as Parkes 0.7–4.2 GHz (6:1 bandwidth) receiver and FAST 0.27–1.62 GHz (6:1 bandwidth) receiver, wider relative bandwidth of the proposed receiver is achieved and it is a new attempt to expand the bandwidth of UWB low-frequency receiver.
- Published
- 2022
39. A MEMS high g acceleration sensor simulation analysis
- Author
-
Yujun Yang, Peng Wang, Manlong Chen, Fan Yang, Yingxuan Liang, and Fangfang Chen
- Subjects
History ,Computer Science Applications ,Education - Abstract
The acceleration sensor with high g value is widely used in a variety of fields, including collision impact, aerospace, and defense security and thus is a key focus in the future. The sensor with a double-ended four-beam structure is investigated in this paper via finite element simulation analysis. The measurement sensitivity of the sensor can be improved by changing the position of the cantilever beam. Furthermore, transverse interference in the X-direction and Y-direction can be eliminated in theory through the layout of piezoresistors and the Wheatstone circuit. The simulation results show that the sensor's sensitivity is 2.6μV/g while its cross-sensitivity in the X-direction and Y-direction is 0%, indicating that the sensor's performance has been substantially improved.
- Published
- 2022
40. Review of Key Technologies of mobile energy storage vehicle participating in distribution network dispatching under the high proportion of renewable energy access
- Author
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Wenpei Li, Bin Xiang, Hu Xiong, Jiayuan Li, and Fan Yang
- Subjects
History ,Computer Science Applications ,Education - Abstract
With modern society’s increasing reliance on electric energy, rapid growth in demand for electricity, and the increasingly high requirements for power supply quality, sudden power outages are bound to cause damage to people’s regular order of life and the normal functioning of society. Currently, the commonly used emergency power protection equipment is mainly based on diesel generator sets, while there is also flywheel energy storage equipment in the application of emergency power protection. In today’s society, we strongly advocate green, energy-saving, and emission reduction background, and the demand for new mobile power supply systems becomes very urgent. Mobile energy storage vehicles can not only charge and discharge, but they can also facilitate more proactive distribution network planning and dispatching by moving around. The basic model and typical application scenarios of a mobile power supply system with battery energy storage as the platform are introduced, and the input process and key technologies of mobile energy storage devices under different operation modes are elaborated to provide strong support for further input and reasonable dispatch of mobile energy storage vehicles.
- Published
- 2022
41. Generalized self-similar spectrum and the effect of large-scale in decaying homogeneous isotropic turbulence
- Author
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Ping-Fan Yang, Alain Pumir, and Haitao Xu
- Subjects
homogeneous and isotropic turbulence ,spectrum ,decaying turbulence ,self-similarity ,Science ,Physics ,QC1-999 - Abstract
In statistically stationary conditions, the turbulent energy spectrum in a high Reynolds number flow exhibits a k ^−5/3 (Kolmogorov) regime, with a faster decay at larger, dissipative wavenumbers. Here, we investigate how the energy spectrum of a turbulent flow evolves in time when turbulence decays freely, in the absence of forcing. Results from direct numerical simulation of decaying turbulence in a periodic box with several different initial conditions suggest a generalized self-similar spectrum, depending on ${k}_{s}=k\times \eta (t)$ and ${k}_{l}=k\times L(t)$ , where η ( t ) and L ( t ) are, respectively, the small (Kolmogorov) and large scales of the flow. A closure method allows us to obtain an explicit form of the spectrum, which reproduces the deviations from the Kolmogorov spectrum at small k observed numerically. The solution can also be used to determine the second and third order structure functions in decaying turbulent flows, and to study their scaling behavior. Our results compare favorably with high-Reynolds number wind tunnel data. Moreover, our theoretical results provide support to the interesting empirical observation by Pearson et al (2002 Phys. Fluids 14 1288–90) that, independent of the large scale structure of the flow, the dimensionless energy dissipation rate is a universal constant when scaled in terms of the turbulent kinetic energy of the flow, and of the length scale corresponding to the peak of the compensated energy spectrum.
- Published
- 2018
- Full Text
- View/download PDF
42. Optical and microstructural characterization of Micro-LED with sidewall treatment
- Author
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Fan Yang, Yu Xu, Lu Li, Xin Cai, Jianjie Li, Jiahao Tao, Shunan Zheng, Bing Cao, and Ke Xu
- Subjects
Acoustics and Ultrasonics ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Abstract
The traditional influence on the sidewall damage of Micro-LED was mostly focused on the research of I-V-L. In this paper, we discussed the influence of Micro-LED sidewall damage from the perspective of optical and microstructural characterization. Scanning electron microscopy showed that the Micro-LED structure with smaller size was more irregular after inductively coupled plasma etching. High-resolution transmission electron microscopy and energy dispersive x-ray spectroscopy analysis showed that the area of the upper and lower regions of the quantum well was inconsistent, there was about 2 nm lattice disorder on the surface of the sidewall of the mesa, and oxygen and silicon impurity atoms were enriched. For optical characterization, a method combining laser scanning confocal microscopy and photoluminescence (PL) was proposed to evaluate the optical performance of the mesa. The results showed that the luminescence of Micro-LED mesa was uneven, the luminous intensity at the edge of the mesa was reduced by more than 65%, and the luminous wavelength was shifted by several nanometers. Finally, we optimized the sidewall treatment process, effectively improved the performance of Micro-LED devices by combining tetramethylammonium hydroxide treatment and SiO2 passivation, and increased the luminous intensity of Micro-LED 2 μm away from the edge by about 4.7 times and PL uniformity was greatly improved. These results provided an available reference for the development of Micro-LED.
- Published
- 2022
43. A novel natural surface-enhanced fluorescence system based on reed leaf as substrate for crystal violet trace detection
- Author
-
Hui-Ju Cao, Hong-Wen Cao, Yue Li, Zhen Sun, Yun-Fan Yang, Ti-Feng Jiao, and Ming-Li Wang
- Subjects
General Physics and Astronomy - Abstract
The preparation of surface-enhanced fluorescence (SEF) substrates is often influenced by experimental strategies and factors such as the morphology and size of the nanostructures. In this study, using the natural reed leaves (RLs) without any special pretreatment as the substrate, metal silver is modified by magnetron sputtering technology to prepare a stable and efficient SEF system. The abundant “hedgehog-like” protrusions on the RL substrate surface can generate high-density “hot spots”, thus enhancement factor (EF) is enhanced up to 3345 times. The stability and reproducibility are verified in many measurements. The contribution of the intervention of silver nanostructure to the radiation attenuation process of fluorescent molecules is analyzed with the aid of Jablonski diagrams. Three-dimensional (3D) finite difference time domain (FDTD) simulates the spatial electric field and “hot spots” distribution of the substrate. The “hedgehog-like” protrusion structure generates multiple “hot spots”, which produce an excellent local surface plasmon resonance (LSPR) effect and provide higher fluorescence signal. Finally, RL/Ag-35 substrate is used to detect crystal violet (CV), and the detection limit is as low as 10−13 M. This “hedgehog-like” SEF substrate provides a new strategy for the trace detection of CV, which has a good practical application value.
- Published
- 2022
44. Analytical formula describing the non-saturating linear magnetoresistance in inhomogeneous conductors
- Author
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Shan-Shan Chen, Yang Yang, and Fan Yang
- Subjects
General Physics and Astronomy - Abstract
The effective-medium theory (EMT) has proved successful in modeling the non-saturating linear magnetoresistance induced by inhomogeneity. However, calculating magnetoresistance using the EMT usually involves solving coupled integral equations which have no analytical solutions, and therefore, it is still difficult to directly compare the predictions of EMT with experimental data. Here we demonstrate that the linear magnetoresistance predicted by the EMT can be either exactly formulated or well approximated by a simple analytical equation Δ ρ / ρ 0 = k 2 B 2 + a 2 − a in a number of known situations. The relations between the EMT parameters and the phenomenological parameters k and a are evaluated. Our results provide a convenient and effective method for extracting the EMT parameters from experimental data.
- Published
- 2022
45. A novel demodulation method for transmission using nitrogen–vacancy-based solid-state quantum sensor
- Author
-
Ruixin Bai, Xinyue Zhu, Fan Yang, Tianran Gao, Ziran Wang, Linyan Yu, Jinfeng Wang, Li Zhou, and Guanxiang Du
- Subjects
General Physics and Astronomy - Abstract
Diamond based quantum sensing is a fast-emerging field with both scientific and technological significance. The nitrogen–vacancy (NV) center, a crystal defect in diamond, has become a unique object for microwave sensing applications due to its excellent stability, long spin coherence time, and optical properties at ambient condition. In this work, we use diamond NV center as atomic receiver to demodulate on–off keying (OOK) signal transmitted in broad frequency range (2 GHz–14 GHz in a portable benchtop setup). We proposed a unique algorithm of voltage discrimination and demonstrated audio signal transceiving with fidelity above 99%. This diamond receiver is attached to the end of a tapered fiber, having all optic nature, which will find important applications in data transmission tasks under extreme conditions such as strong electromagnetic interference, high temperatures, and high corrosion.
- Published
- 2022
46. NiCo alloy/C nanocomposites derived from a Ni-doped ZIF-67 for lightweight microwave absorbers
- Author
-
Zhang, Ximing, primary, Wang, Jingyu, additional, Fan, Yang, additional, Ren, Hengdong, additional, Liu, Zhenying, additional, Wang, Yanfen, additional, Liu, Yin, additional, Bai, Hongcun, additional, and Kong, Lingbing, additional
- Published
- 2021
- Full Text
- View/download PDF
47. Study on analytical model of gas diffusion in underground pipe network
- Author
-
Tian Zhou, Fan Yang, Wei Liu, and Yue Tan
- Subjects
History ,Computer Science Applications ,Education - Abstract
Through the analysis of gas pipeline leakage causes and gas leakage diffusion model, the preventive measures for gas leakage accidents are put forward, which is of great significance for the harm of gas leakage and explosion accidents. In this paper, the mathematical model of gas leakage is established through hydrodynamics and pipeline gas motion equation, and the leakage process is analyzed by means of numerical simulation, the change law of gas dynamic leakage is obtained from the aspects of gas leakage conditions, gas movement and diffusion law.
- Published
- 2022
48. Analysis of rainwater overflow in underground pipe network
- Author
-
Tian Zhou, Fan Yang, Wei Liu, and Yue Tan
- Subjects
History ,Computer Science Applications ,Education - Abstract
Urban rainwater pipe network is a direct way to resist urban waterlogging, and its safe and stable operation is the premise to ensure the normal operation of the city. However, in China and even around the world, the monitoring means for the operation of urban rainwater pipe network are very limited. For the occurrence and solution of urban waterlogging, it often mainly depends on the means of personnel inspection to monitor where the rainwater pipe network overflows, and then take measures. There is no effective monitoring method for the whole rainwater pipe network. Therefore, an accurate and efficient rainwater pipe network monitoring method is urgently needed. To solve the current problem of real-time monitoring of rainwater pipe network, the core problem is how to monitor the liquid level data of any pipe section of the whole rainwater pipe network in real time, so it is necessary to introduce hydrodynamic model. The traditional hydrodynamic model mainly simulates the hydraulic and hydrological, and does not simulate the rainwater pipe network, but makes a generalized estimation of the drainage of the rainwater pipe network. In addition, some hydrodynamic models for drainage pipe network are not established for the problem of rainwater pipe network monitoring. The ultrasonic liquid level gauge with real-time acquisition function is not introduced into the calculation simulation, and it does not have the ability of adaptive correction. Therefore, the traditional rainwater monitoring methods and hydrodynamic models can not fundamentally solve the problem of real-time monitoring of the whole rainwater pipe network. Using hydrodynamic model calculation, combined with rain gauge and liquid level gauge to monitor and modify model parameters, so as to intelligently monitor the whole rainwater pipe network, which can greatly improve the current monitoring level of urban rainwater pipe network and reduce the work cost of manual patrol monitoring.
- Published
- 2022
49. Effect of Particle Combination Ratio of Soil Rock Mixture on Shear Strength
- Author
-
Shengting Li, Rui Zhou, Fan Yang, Yangchun Zhang, and Yongjun Du
- Subjects
History ,Computer Science Applications ,Education - Abstract
With the increase of fine-grained soil content, the properties continue to transform to fine-grained soil, which will affect the permeability and strength of the soil. Even if the content of silt and clay in fine-grained soil is not high, it will significantly impact soil properties. When the content of coarse particles is low, the nature of soil depends on the fine particles in the soil. When the content of coarse particles gradually increases, and the coarse particles are overhead, the nature of soil only depends on the coarse-grained soil, and the influence of fine particles on the nature of soil gradually weakens. To reveal the interaction mechanism between coarse and fine particles in high moisture content clayey gravel, this project conducts a systematic experimental study on the high moisture content clayey gravel, takes 0.5mm as the particle size limit, takes the separation of coarse and fine particles in the soil sample as the control test, and systematically tests the shear strength of the separated fine particles; systematic shear strength tests were also carried out on the separated coarse particles. In addition, shear strength tests were carried out on soil samples with different fine particle content.
- Published
- 2022
50. First-Principles Study of Hole-Doped Superconductors RNiO2 (R = Nd, La, and Pr)
- Author
-
Juan-Juan Hao, Pei-Han Sun, Ming Zhang, Xian-Xin Wu, Kai Liu, and Fan Yang
- Subjects
General Physics and Astronomy - Abstract
Recent experiments have found that in contrast to the nonsuperconducting bulk RNiO2 (R = Nd, La, and Pr), the strontium-doped R 1 – x Sr x NiO 2 thin films show superconductivity with the critical temperature T c of 9–15 K at x = 0.2, whose origin of superconductivity deserves further investigation. Based on first-principles calculations, we study the electronic structure, lattice dynamics, and electron–phonon coupling (EPC) of the undoped and doped RNiO2 (R = Nd, La, and Pr) at the experimental doping level. Our results show that the EPC-derived T c’s are all about 0 K in the undoped and doped RNiO2. The electron–phonon coupling strength is too small to account for the observed superconductivity. We hence propose that the electron–phonon interaction can not be the exclusive origin of the superconductivity in RNiO2 (R = Nd, La, and Pr).
- Published
- 2022
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