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The latest progress of Five-hundred-meter Aperture Spherical radio Telescope

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Science China(Technological Sciences) 2022年第4期65卷 987-988页

作者： JIANG Peng yao rui CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

After nearly two years of operation,FAST has acquired abundant scientific achievements,and more than one hundred high-quality papers have been published based on the FAST data[1–6],which have produced far-reaching scientific achievements in ***,FAST data plays an important role in constraining the physical origin of fast radio *** corresponding results have been published in the journal“Nature”.

关键词： journal FAST hundred

Accuracy Analysis of Stewart Platform Based on Interval Analysis Method

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Chinese Journal of Mechanical Engineering 2013年第1期26卷 29-34页

作者： yao rui ZHU Wenbai HUANG Peng National Astronomical Observatories Chinese Academy of Sciences Department of Precision Instruments and Mechanology Tsinghua University

A Stewart platform is introduced in thc 500 m aperture spherical radio telescope（FAST） as an accuracy adjustable mechanism for teed receivers. Accuracy analysis is the basis of accuracy design. However, a rapid and effective accuracy analysis method for parallel manipulator is still needed. In order to enhance solution efficiency, an interval analysis method（lA method） is introduced to solve the terminal error bound of the Stewart platform with detailed solution path. Taking a terminal pose of the Stewart platform in FAST as an example, the terminal error is solved by the Monte Carlo method（MC method） by 4 980 s, the stochastic mathematical method（SM method） by 0.078 s, and the IA method by 2.203 s. Compared with MC method, the terminal error by SM method leads a 20% underestimate while the IA method can envelop the real error bound of the Stewart platform. This indicates that the IA method outperforms the other two methods by providing quick calculations and enveloping the real error bound of the Stewart platform. According to the given structural error of the dimension parameters of the Stewart platform, the IA method gives a maximum position error of 19.91 mm and maximum orientation error of 0.534°, which suggests that the IA method can be used for accuracy design of the Stewart platfbnn in FAST. The 1A method presented is a rapid and effective accuracy analysis method for Stewart platform.

关键词： Stewart platform accuracy interval analysis radio telescope

Pose optimization of the FAST feed support system based on the new feed cabin mechanism

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 178-187页

作者： Jianing Yin Peng Jiang rui yao CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

The Five-hundred-meter Aperture Spherical radio Telescope(FAST) is the largest and most sensitive single-dish radio telescope in the world and has made many important scientific achievements in a few years. Given the enormous scientific research potential of the Milky Way center, it is necessary to enhance the observation zenith angle as close to the Milky Way center as possible. In this regard, a new mechanism for the feed cabin is proposed with cables and sliders, which is lighter in weight and larger in the workspace. This paper will introduce this new feed cabin and the whole feed support system and establish their mechanical models to optimize the relevant control parameters, making FAST achieve an observation zenith angle of at least 50°with satisfying the required constraints. It indicates that the new mechanism designed by the FAST team can be used for the FAST upgrade and the future FAST array project.

关键词： radio telescope cable-driven parallel robot mechanism optimization

Multi-objective evolutionary design of selective triple modular redundancy systems against SEUs

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Chinese Journal of Aeronautics 2015年第3期28卷 804-813页

作者： yao rui Chen Qinqin Li Zengwu Sun Yanmei College of Automation and Engineering Nanjing University of Aeronautics and Astronautics

Abstract To improve the reliability of spaceborne electronic systems, a fault-tolerant strategy of selective triple modular redundancy （STMR） based on multi-objective optimization and evolvable hardware （EHW） against single-event upsets （SEUs） for circuits implemented on field pro- grammable gate arrays （FPGAs） based on static random access memory （SRAM） is presented in this paper. Various topologies of circuit with the same functionality are evolved using EHW firstly. Then the SEU-sensitive gates of each circuit are identified using signal probabilities of all the lines in it, and each circuit is hardened against SEUs by selectively applying triple modular redundancy （TMR） to these SEU-sensitive gates. Afterward, each circuit hardened has been evaluated by SEU Simulation, and the multi-objective optimization technology is introduced to optimize the area overhead and the number of functional errors of all the circuits, The proposed fault-tolerant strategy is tested on four circuits from microelectronics center of North Carolina （MCNC） benchmark suite. The experimental results show that it can generate innovative trade-off solutions to compromise between hardware resource consumption and system reliability. The maximum savings in the area overhead of the STMR circuit over the full TMR design is 58% with the same SEU immunity.

关键词： Evolvable hardware Field programmable gatearray Multi-objective approachSelective triple modularredundancy Single event upset

An approximately analytical solution method for the cable-driven parallel robot in FAST

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Research in Astronomy and Astrophysics 2021年第2期21卷 169-179页

作者： Jia-Ning Yin Peng Jiang rui yao National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

The Five-hundred-meter Aperture Spherical radio Telescope(FAST)is the largest single-dish aperture telescope with a cable-driven parallel robot introduced to achieve the highest sensitivity in the ***,to realize the high-precision,mechanical equations of such a robot are always complicated,so that it is difficult to achieve real-time control by the traditional iterative *** this regard,this paper proposes an approximately analytical solution method,which uses the approximately linear relationship between the main parameters of FAST to bypass some *** the coefficients of the relationship extracted,static or quasi-static mechanical equations can be analytically *** this paper’s example,this method saves at least 90%of the calculating time and the calculated values are consistent with the experimental *** such huge efficiency improvements,real-time and high-precision control of the FAST will no longer be difficult ***,all the work in this paper is expected to be used in the FAST.

关键词： telescopes-methods analytical-instrumentation miscellaneous

A self-healing strategy with fault-cell reutilization of bio-inspired hardware

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Chinese Journal of Aeronautics 2019年第7期32卷 1673-1683页

作者： Zhai ZHANG yao QIU Xiaoliang YUAN rui yao Yan CHEN Youren WANG College of Automation Engineering Nanjing University of Aeronautics and Astronautics

The self-healing strategy is a key component in designing the bio-inspired embryonics circuit with the structure of cell arrays. However, the existing self-healing strategies of embryonics circuits mainly focus on permanent faults inside the modules of cells such as the function module and the configuration register, while little attention is paid to transient faults. From the point of view of obtaining high efficiency of hardware utilization, it would be a huge waste of hardware resources by permanent elimination when a cell only suffers a transient fault which can be repaired by a configuration mechanism. A new self-healing strategy, the Fault-Cell Reutilization Self-healing Strategy(FCRSS) which presents a method for reusing transient fault cells, is proposed in this paper. The circuit structures of all the modules in the cells are described in detail. In the new strategy, two processes of elimination and reconfiguration are combined. Within the process of fault-cell elimination, cells with transient faults in the embryonics circuit array could be reused simultaneously to replace the functions of the cells on their left side in the same row. Therefore, transient fault-cells in a transparent state can be reconfigured to realize the fault-cell reutilization. Finally,a circuit simulation, resource consumption, a reliability analysis and a detailed normalization analysis are presented. The FCRSS can improve the hardware utilization rate and system reliability at the expense of a small amount of hardware resources and reconfiguration time. Following the conclusion, the method of determining the optimal self-healing strategy is presented according to the environmental conditions.

关键词： Bio-inspired hardware Embryonics Fault-cell reutilization Reliability analysis Self-healing strategy Transient fault

Posttraumatic stress symptoms among Chinese university students during the COVID-19 pandemic:Prevalence,correlates,and mental health help-seeking

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World Journal of Psychiatry 2025年第1期15卷 145-152页

作者： rui-yao Wu Lin-Feng Ge Bao-Liang Zhong Department of Psychiatry The Affiliated Wuhan Mental Health CenterTongji Medical College of Huazhong University of Science&TechnologyWuhan 430012Hubei ProvinceChina Department of Psychiatry Wuhan Mental Health CenterWuhan 430012Hubei ProvinceChina

BACKGROUND Revisiting the epidemiology of posttraumatic stress symptoms(PTSSs)among university students during the coronavirus disease 2019(COVID-19)pandemic as well as understanding the mental health help-seeking behavior of individuals with PTSSs has critical implications for public mental health strategies in future medical *** To investigate the prevalence and correlates of PTSSs among university students during the first wave of the COVID-19 pandemic in China and to examine mental health help-seeking behaviors among these *** A total of 2507 Chinese university students were recruited via snowball *** students completed the Seven-item Screening Scale for Post-traumatic Stress Disorder during the first wave of the COVID-19 pandemic in ***-graphic characteristics,pandemic-related characteristics,and mental health help-seeking behaviors of students with PTSSs were also *** The prevalence of PTSSs among the participants was 28.0%.Seven significant correlates of PTSSs were identified(odds ratio=1.23-3.65,P≤0.024):Female sex,being 19 years old or older,living with others or alone,a low level of family economic status,fair or poor interpersonal relationships,severe or very severe local pandemic,and having family members diagnosed with ***,only 3.28%of the students with PTSSs reported seeking help from mental health *** the 23 students who sought help from mental health specialists,13 opted for online or telephone-based psychological *** Our data suggest that there was a high risk of PTSSs among university students and a high level of unmet mental health needs during the COVID-19 *** delivery of mental health services online or via telephone is a promising approach to address these unmet needs.

关键词： Posttraumatic stress symptoms University students COVID-19 Mental health help-seeking China

Hydrological Processes in the Huaihe River Basin, China： Seasonal Variations, Causes and Implications

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Chinese Geographical Science 2018年第4期28卷 636-653页

作者： SUN Peng SUN Yuyan ZHANG Qiang yao rui College of Geography and Tourism Anhui Normal University Wuhu 241002 China Anhui Key Laboratory of Natural Disaster Process and Prevention Wuhu 241002 China Key Laboratory of Water Conservancy and Water Resources of Anhui Province Water Resources Research Institute of Anhui Province and Huaihe River China Bengbu 233000 China Key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China Academy of Disaster Reduction and Emergency Management Faculty of Geographical Science Beijing Normal University Beijing 100875 China

Understanding streamflow changes in terms of trends and periodicities and relevant causes is the first step into scientific management of water resources in a changing environment. In this study, monthly streamflow variations were analyzed using Modified Mann-Kendall(MM-K) trend test and Continuous Wavelet Transform(CWT) methods at 9 hydrological stations in the Huaihe River Basin. It was found that: 1) streamflow mainly occurs during May to September, accounting for 70.4% of the annual total streamflowamount with Cv values between 0.16–0.85 and extremum ratio values between 1.70–23.90; 2) decreased streamflow can be observed in the Huaihe River Basin and significant decreased streamflow can be detected during April and May, which should be the results of precipitation change and increased irrigation demand; 3) significant periods of 2–4 yr were detected during the 1960 s, the 1980 s and the 2000 s. Different periods were found at stations concentrated within certain regions implying periods of streamflow were caused by different influencing factors for specific regions; 4) Pacific Decadal Oscillation(PDO) has the most significant impacts on monthly streamflow mainly during June. Besides, Southern Oscillation Index(SOI), North Atlantic Oscillation(NAO) and the Ni?o3.4 Sea Surface Temperature(Ni?o3.4) have impacts on monthly streamflow with three months lags, and was less significant in time lag of six months. Identification of critical climatic factors having impacts on streamflow changes can help to predict monthly streamflow changes using climatic factors as explanatory variables. These findings were well corroborated by results concerning impacts of El Nino-Southern Oscillation(ENSO) regimes on precipitation events across the Huaihe River Basin. The results of this study can provide theoretical background for basin-scale management of water resources and agricultural irrigation.

关键词： streamflow trend periodicity abrupt behavior climate indices Huaihe River Basin China

Amorphous NiFeB nanoparticles realizing highly active and stable oxygen evolving reaction for water splitting

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Nano Research 2018年第3期11卷 1664-1675页

作者： Guang Liu Dongying He rui yao Yong Zhao Jinping Li Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization Research Institute of Special Chemicals Taiyuan University ofTechnology Taiyuan 030024 China

The development of highly efficient and inexpensive catalysts for oxygen evolving reactions （OERs） is extremely urgent for promoting the overall efficiency of water splitting. Herein we report the fabrication of a series of amorphous NiFeB nanoparticles with varying atomic ratios of Fe to （Ni ＋ Fe）（XFe） by a facile chemical-reduction method. The amorphous NiFeB （XFe=0.20） nanoparticles, combining the merits of in situ formation of borate-enriched NiFeOOH catalytic surface layers, intrinsic amorphous nanostructures, and an optimized degree of Fe doping, displayed highly active electrocatalytic performance towards the OER in a broad range of pH values （from alkaline to neutral conditions）. The catalyst exhibited a relatively low overpotential of 216 mV with a Tafel slope of 40 mWdec on Ni foam and 251 mV with a Tafel slope of 43 mV/dec on glassy carbon at 10 mA/cm2 in a 1 M KOH solution, demonstrating much greater OER efficiency than that of commercial RuO2. Long-term stability testing of the OER performance of NiFeB （XFe = 0.20） by chronoamperometry （overpotential （η） = 320 mV） over 200 h revealed no evidence of degradation. Facile, scalable synthesis and highly active water oxidation make the NiFeB nanoparticles very attractive for OER electrocatalysis.

关键词： amorphous NiFeB electrocatalyst oxygen evolving reaction water splitting