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Forecast of cosmological constraints with superluminous supernovae from the Chinese Space Station Telescope

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 132-142页

作者： Xuan-Dong Jia Jian-Ping Hu fa-Yin wang Zi-Gao Dai School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education Department of Astronomy University of Science and Technology of China

Superluminous supernovae（SLSNe） are a class of intense celestial events that can be standardized for measuring cosmological parameters, bridging the gap between type Ia supernovae and the cosmic microwave background. In this work, we discuss the cosmological applications of SLSNe from the Chinese Space Station Telescope（CSST）. Our estimation suggests that SLSNe rate is biased tracing the cosmic star formation rate, exhibiting a factor of （1 + z）1.2. We futher predict that CSST is poised to observe ～360 SLSNe in the 10 square degrees ultra-deep field survey within a span of 2.5 years. A stringent constraint on cosmological parameters can be derived from their peak-color relationship. CSST is anticipated to uncover a substantial number of SLSNe, contributing to a deeper understanding of their central engines and shedding light on the nature of dark energy at high redshifts.

关键词： supernovae cosmology cosmological constant

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Magnetism and Superconductivity in the t–J Model of La_(3)Ni_(2)O_7 Under Multiband Gutzwiller Approximation

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Chinese Physics Letters 2024年第5期41卷 97-106页

作者：薛洁然王垡 International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

The recent discovery of possible high temperature superconductivity in single crystals of La_(3)Ni_(2)O_(7) under pressure renews the interest in research on *** density functional theory calculations reveal that both d_(z^(2)) and d_(x^(2)-y^(2)) orbitals are active,which suggests a minimal two-orbital model to capture the low-energy physics of this *** this work,we study a bilayer two-orbital t–J model within multiband Gutzwiller approximation,and discuss the magnetism as well as the superconductivity over a wide range of the hole *** to the inter-orbital super-exchange process between d_(z^(2)) and d_(x^(2)-y^(2)) orbitals,the induced ferromagnetic coupling within layers competes with the conventional antiferromagnetic coupling,and leads to complicated hole doping dependence for the magnetic properties in the *** increasing hole doping,the system transfers to A-type antiferromagnetic state from the starting G-type antiferromagnetic(G-AFM)*** also find the inter-layer superconducting pairing of d_(x^(2)-y^(2)) orbitals dominates due to the large hopping parameter ofd_(z^(2)) along the vertical inter-layer bonds and significant Hund’s coupling between d_(z^(2)) and d_(x^(2)-y^(2)) ***,the G-AFM state and superconductivity state can coexist in the low hole doping *** take account of the pressure,we also analyze the impacts of inter-layer hopping amplitude on the system properties.

关键词： properties doping orbital

Calibration and experimental verification of discrete element parameters of Panax notoginseng root

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 13-23页

作者： Kaiting Xie Zhaoguo Zhang fa’an wang Xiaolan Yu Chenglin wang Shifei Jiang faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500China faculty of Modern Agricultural Engineering Kunming University of Science and TechnologyKunming 650500China Guizhou Agricultural Machinery Technology Promotion Station Guiyang 550003China Yunnan Tobacco Machinery Co. LtdKunming 650100China

Existing discrete element method-based simulation analysis of Panax notoginseng root soil separation still has the challenge to get the accurate and reliable basic parameters,which are necessary for discrete element *** this paper,the *** roots suitable for harvesting period were taken as the experimental *** using 3D scanning reverse modeling technology and EDEM software to establish the discrete element model of ***,based on which,the physical and virtual tests were carried out to calibrate the simulation ***,the basic physical parameters(density,triaxial geometric size,moisture content,shear modulus,and elastic modulus)and contact coefficients(static friction coefficient,rolling friction coefficient,and crash recovery coefficient between *** roots and 65Mn steel)were measured by physical ***,treating the contact coefficients of *** roots as the influence factor,the steepest uphill test,and four factors combing five levels of rotational virtual simulation are *** measured relative error accumulation angle and simulation accumulation angle are set as the performance *** results show that the static friction coefficient,rolling friction coefficient,crash recovery coefficient,and surface energy coefficient of *** roots are 0.55,0.35,0.16,and 19.5 J/m2,*** calibration results as parameters of the vibration separation simulation test of *** soil,the Box-Behnken vibration separation simulation tests were carried out,in which the vibration frequency,inclination angle,and vibration amplitude of separation device as factors,screening rate and damage rate of *** soil complex are regarded as *** results show that the optimal operating parameters of the separation device are the vibration frequency of 10 Hz,the inclination angle of 5°,and the amplitude of 6 *** on the optimal operation parameters,the discrete element

关键词： Panax notoginseng root EDEM parameter calibration separation test

Is the time right for systematically serotyping SARS-related coronaviruses?

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hLife 2024年第1期2卷 4-5页

作者： Chee Wah Tan Lin-fa wang Department of Microbiology and Immunology Yong Loo Lin School of MedicineNational University of SingaporeSingapore CitySingapore Duke-NUS Medical School Singapore CitySingapore

IS THERE A NEED FOR SEROTYPING?The emergence and rapid selection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)immune escape variants have exerted significant challenges in many different ways,from public health response to vaccine boosting strategy and monitoring of herd immunity against future variants or related severe acute respiratory syndrome(SARS)related coronaviruses(SARSr-CoVs).The Omicron sub-variants,which differ substantially from the pre-Omicron variants,are circulating worldwide and continuing to evolve extensively through mutations and/or recombination predominantly in the spike protein,mainly due to immune-selective *** their phylogenetically close relationship to ancestral SARS-CoV-2,antigenically,Omicron variants are very different from the original *** is therefore very natural to raise the question whether we need a better way to classify and differentiate those CoVs which are genetically very similar,but antigenically quite *** of viruses is a common practice for many known virus groups,most notably for human papillomavirus(HPV)and dengue virus(DENV)[1,2].The concept of CoV serotypes was not new and has been applied to study the antigenicity of feline CoVs[3].The possibility of establishing distinctive serotypes for the SARS-CoV-2 virus was first raised by Simon-Loriere and Schwartz in 2022[4].Serotyping SARS-CoV-2 is expected to help more scientifically define the differences between variants and facilitate more targeted diagnostics,therapeutics,and vaccine development.

关键词： immunity SARS establishing

Identified the hydrochemical and the sulfur cycle process in subsidence area of Pingyu mining area using multi-isotopes combined with hydrochemistry methods

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Journal of Groundwater Science and Engineering 2024年第1期12卷 62-77页

作者： Hui-Meng Su fa-wang Zhang Jing-Yu Hu Jin-Feng Lei Wei Zuo Bo Yang Yu-Hua Liu School of Environmental Studies China University of GeosciencesWuhan 430074China Center for Hydrogeology and Environmental Geology China Geological SurveyBaoding 071051Hebei ProvinceChina Henan Branch China South-to-North Water Diversion Middle Route Corporation LimitedZhengzhou 450046China The Fifth Geological Survey Institute Henan Provincial Bureau of Geology and Mineral ResourcesZhengzhou 450012China Natural Resources Science and Technology Innovation Center of Henan Province(Research on Eco-Environmental Assessment and Restoration Technology) Zhengzhou 450012China

Groundwater serves as an important water source for residents in and around mining *** achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the chemical formation process and the ground water sulfur cycle that transpire after the coal mining *** on studies of hydrochemistry and D,^(18)O-H_(2)O,^(34)S-SO_(4)isotopes,this study applied principal component analysis,ion ratio and other methods in its attempts to reveal the hydrogeochemical action and sulfur cycle in the subsidence area of Pingyu mining *** study discovered that,in the studied area,precipitation provides the major supply of groundwater and the main water chemistry effects are dominated by oxidation dissolution of sulfide minerals as well as the dissolution of carbonate and silicate *** sulfate in groundwater primarily originates from oxidation and dissolution of sulfide minerals in coal-bearing strata and human *** mixed sulfate formed by the oxidation of sulfide minerals and by human activities continuously recharges the groundwater,promoting the dissolution of carbonate rock and silicate rock in the process.

关键词： PCA Ion ratio Water chemistry Sulfide minerals Multi-isotopes Subsidence area of mining area

Scintillation Arc from FRB 20220912A

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 134-142页

作者： Zi-Wei Wu Robert AMain Wei-Wei Zhu Bing Zhang Peng Jiang Jia-Rui Niu Jin-Lin Han Di Li Ke-Jia Lee Dong-Zi Li Yuan-Pei Yang fa-Yin wang Rui Luo Pei wang Chen-Hui Niu Heng Xu Bo-Jun wang Wei-Yang wang Yong-Kun Zhang Yi Feng De-Jiang Zhou Yong-Hua Xu Can-Min Deng Yu-Hao Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Max-Planck-Institut für Radioastronomie Bonn 53121Germany Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Nevada Center for Astrophysics and Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA CAS Key Laboratory of faST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Cahill Center for Astronomy and Astrophysics California Institute of TechnologyPasadena 91125USA South-Western Institute For Astronomy Research Yunnan UniversityKunming 650504China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China CSIRO Space and Astronomy Epping 1710Australia Department of Astronomy School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Guangxi Key Laboratory for Relativistic Astrophysics Department of PhysicsGuangxi UniversityNanning 530004China

We present the interstellar scintillation analysis of fast radio burst(FRB)20220912A during its extremely active episode in 2022using data from the Five-hundred-meter Aperture Spherical Radio Telescope(faST).We detect a scintillation arc in the FRB’s secondary spectrum,which describes the power in terms of the scattered FRB signals’time delay and Doppler *** arc indicates that the scintillation is caused by a highly localized *** analysis favors a Milky Way origin of the ionized interstellar medium(IISM)for the localized scattering medium but cannot rule out a host galaxy *** present our method for detecting the scintillation arc,which can be applied generally to sources with irregularly spaced bursts or *** methods could help shed light on the complex interstellar environment surrounding the FRBs and in our Galaxy.

关键词： fast radio burst scintillation FRB 20220912A

Groundwater and environmental challenges in Asia

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Journal of Groundwater Science and Engineering 2024年第2期12卷 223-236页

作者： Yan-pei Cheng fa-wang Zhang Hua Dong Xue-ru Wen Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Key Laboratory of Groundwater Sciences and Engineering Ministry of natural ResourcesZhengding 050803HebeiChina Center for Hydrogeology and Environmental Geology Survey China Geological SurveyBaoding 071051HebeiChina

Asia stands out as the most populous and geographically diverse region *** pressing issues of water resource development and the resulting ecological impacts are exacerbated by the region's rapid population growth and economic ***,a vital source of water in Asia,faces significant disparities in distribution and suffers from unsustainable exploitation *** study applies groundwater system theory and categorizes Asia into 11 primary groundwater systems and 36 secondary ones,based on intercontinental geological structures,climate,terrain,and hydrogeological *** of the end of 2010,Asia's assessed groundwater resources totalled 4.677×10^(9) m^(3)/a,with exploitable resources amounting to 3.274×10^(9) m^(3)/*** considering the geological environmental impacts of groundwater development and the distinctive characteristics of terrain and landforms,six categories of effect zones with varying distribution patterns are *** current research on Asia's groundwater resources,environmental dynamics,and human impacts aims to provide a theoretical foundation for sustainable groundwater management and environmental conservation in the region.

关键词： Asia Groundwater resources Groundwater quality Ecological environment Environmental impacts

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基于区间二型模糊逻辑的制动防抱死控制

交通运输工程学报 2024年第3期24卷 238-250页

作者：王骏骋吕林峰王法慧浙江理工大学机械工程学院浙江杭州310018

针对传统模糊逻辑制动防抱死控制抗干扰能力较弱,在面对不同路面附着系数及理想滑移率时滑移率控制效果较差的问题,提出了一种区间二型模糊逻辑制动防抱死控制系统和方法;控制系统以滑移率误差为输入,利用区间二型模糊集合描述了滑移率... 详细信息

针对传统模糊逻辑制动防抱死控制抗干扰能力较弱,在面对不同路面附着系数及理想滑移率时滑移率控制效果较差的问题,提出了一种区间二型模糊逻辑制动防抱死控制系统和方法;控制系统以滑移率误差为输入,利用区间二型模糊集合描述了滑移率误差及其变化率,并经模糊化、模糊推理、模糊降型、解模糊化4个步骤得到理想制动力矩输出;根据上、下隶属度函数确定的模糊变量隶属度计算模糊规则激活度区间,以增强系统的抗干扰能力,并保证滑移率精准跟踪;基于MATLAB/SIMULINK软件,针对搭载了提出的控制器与传统控制器的车辆,模拟了在不同路面附着条件下的防抱死控制性能,并搭建了防抱死硬件在环平台,进行了验证分析。研究结果表明:在区间二型模糊逻辑制动防抱死控制下,车辆在低附着系数路面下前、后轮滑移率误差均方分别下降了52.96%和57.36%,制动距离缩短了0.24 m,制动时间降低了0.04 s;在中附路面下前、后轮滑移率误差均方分别下降了65.15%和73.32%,制动距离缩短了0.36 m,制动时间降低了0.05 s;在高附着系数路面下前、后轮滑移率误差均方分别下降了47.20%和39.57%,制动距离缩短了0.19 m,制动时间降低了0.02 s。由此可见,相比于传统模糊逻辑制动防抱死控制,提出的区间二型模糊逻辑制动防抱死控制在不同制动条件下均能取得更好的滑移率控制效果。

关键词：汽车工程制动防抱死抗干扰能力滑移率区间二型模糊逻辑模糊降型隶属度函数硬件在环

基于SSK的室内VLPC系统设计及性能分析

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电子学报 2024年第6期52卷 1809-1816页

作者：王法松姜雯李睿史士杰郑州大学电气与信息工程学院河南郑州450001 河南工业大学理学院河南郑州450001

本文设计了一个多输入单输出(Multiple-Input Single-Output,MISO)的三维室内可见光定位通信一体化(Visible Light Position and Communication,VLPC)系统,该系统在接收端基于接收信号强度(Received Signal Strength,RSS)的三维可见光定位(Visible Light Position,VLP)算法获得定位数据,同时估计信道状态信息(Channel State Information,CSI)并上传给发射端进行定向通信.该系统的发射端基于空移键控(Space Shift Keying,SSK)的室内可见光通信(Visible Light Communication,VLC)技术实现系统的通信功能.另外,本方案可以完全避免通信与定位子系统之间的干扰.同时,通过推导定位误差的克拉美罗下界(Cramér-Rao Lower Bound,CRLB)和SSK-VLC的通信可达速率来评估本文提出的VLPC系统的性能.仿真结果验证了本文所提方案的有效性.

关键词：可见光定位可见光通信空移键控克拉美罗下界可达速率