From the case study of Evening Bell Ringing at Nanping Hill,one of the West Lake Cultural Landscapes in Hangzhou,China,we investigated the soundscape of a scenic area with a profound cultural background.First,we condu...From the case study of Evening Bell Ringing at Nanping Hill,one of the West Lake Cultural Landscapes in Hangzhou,China,we investigated the soundscape of a scenic area with a profound cultural background.First,we conducted the soundscape physical index of the area in both winter and spring seasons to analyze its objective graphical expression.Second,we focused on people's reactions to the soundscape in order to obtain a subjective evaluation of each component in the soundscape and integrated environment.Then,the relationship between the objective data and the subjective evaluation was analyzed.Finally,the impacts of the natural environment,history,and cultural factors on the evaluation of the Jingci Temple soundscape were studied.It was found that natural sounds,cultural sounds,and historic sounds were widely acclaimed in people's subjective feelings,which indicated the close relationships among historical and cultural background,soundscape,and natural environment.Thus,the conclusion was made that soundscape should be consistent with the local natural environment and the historical and cultural background.展开更多
Honji instability and ringing of offshore structrures are two different phenomena. Honji instability occurs at a circular cylinder in transverse periodic finite motion in a water tank. It is superposed on the streamin...Honji instability and ringing of offshore structrures are two different phenomena. Honji instability occurs at a circular cylinder in transverse periodic finite motion in a water tank. It is superposed on the streaming flow induced by the cylinder’s boundary layer. Its oscillation period is half of the period of the cylinder oscillation. Finite volume calculations of the filtered Navier-Stokes equations visualize the three-dimensional instability, where fluid particles transported by the circumferencial roll pairs exhibit a periodic mushroom-like pattern. Force is the same with and without the Honji instability. The large eddy simulation calculations for high Reynolds number support a drag coefficient in accordance with the Stokes-Wang solution below separation and conform with experimental measurements of the damping force on a harmonically oscillating cylinder. Ringing of offshore structures are vibrations which appear at natural frequencies and concern fatigue. It is generated by a higher harmonic force oscillating with frequency being 3-4 times the fundamental wave frequency. Together with a strong inertia load in phase with the incoming wave’s acceleration, a secondary load cycle appears in strong seas when the wave crest leaves the structure; this occurs about 1/4 wave period after the main force peak, it starts when the wave crest is about one cylinder radius behind the cylinder, lasts for about 15-20 percent of the wave period and has a magnitude up to 11 % of the peak-to-peak total force. It is a gravity effect and appears in strong irregular seas when kA > 0.18 and um/√gD > 0.4 (k wavenumber, A amplitude, um maximal wave induced velocity, g acceleration of gravity, D cylinder diameter).展开更多
Ringing artifact degradations always appear in the deconvolution of geophysical data. To address this problem, we propose a postprocessing approach to suppress ringing artifacts that uses a novel anisotropic diffusion...Ringing artifact degradations always appear in the deconvolution of geophysical data. To address this problem, we propose a postprocessing approach to suppress ringing artifacts that uses a novel anisotropic diffusion based on a stationary wavelet transform （SWT） algorithm. In this paper, we discuss the ringing artifact suppression problem and analyze the characteristics of the deconvolu- tion ringing artifact. The deconvolution data containing ringing artifacts are decomposed into different SWT sub- bands for analysis, and a new multiscale adaptive aniso- tropic filter is developed to suppress these degradations. Finally, we demonstrate the performance of the proposed method and describe the experiments in detail.展开更多
This paper presents a numerical study on the high-frequency wave loads and ringing response of offshore wind turbine foundations exposed to moderately steep transient water waves.Input wave groups are generated by the...This paper presents a numerical study on the high-frequency wave loads and ringing response of offshore wind turbine foundations exposed to moderately steep transient water waves.Input wave groups are generated by the technique of frequency-focusing,and the numerical simulation of focused waves is based on the NewWave model and a Fourier time-stepping procedure.The proposed model is validated by comparison with the published laboratory data.In respect of both the wave elevations and the underlying water particle kinematics,the numerical results are in excellent agreement with the experimental data.Furthermore,the local evolution of power spectra and the transfer of energy into higher frequencies can be clearly identified.Then the generalized FNV theory and Rainey’s model are applied respectively to calculate the nonlinear wave loads on a bottom-hinged vertical cylinder in focused waves.Resonant ringing response excited by the nonlinear high-frequency wave loads is found in the numerical simulation when frequency ratios(natural frequency of the structure to peak frequency of wave spectra)are equal to 3–5.Dynamic amplification factor of ringing response is also investigated for different dynamic properties(natural frequency and damping ratio)of the structure.展开更多
We investigate the evolution of an electromagnetic field in the spacetime of a stringy black hole.The objectpicture of the quasinormal ringing has been obtained by the finite difference method.Compared with a Schwarzs...We investigate the evolution of an electromagnetic field in the spacetime of a stringy black hole.The objectpicture of the quasinormal ringing has been obtained by the finite difference method.Compared with a Schwarzschildblack hole,the results show that the electromagnetic field damps more slowly for a stringy black hole.展开更多
The exponential application of mobile technology has led to a concern about implications of electromagnetic radiation on human health. As we are aware that mobile phone radiates EMR when users communicate to others an...The exponential application of mobile technology has led to a concern about implications of electromagnetic radiation on human health. As we are aware that mobile phone radiates EMR when users communicate to others and that time subscribers of the device are regularly exposed nearby 40% - 50% of total mobile irradiation. We analyzed the risk of "Ringing Delusion" among normal users, moderate users and heavy users when compared to low users. Although the "Ringing Delusion" has not been added in medical terminology but we found frequently such kind of symptoms among mobile phone users. "Ringing Delusion" may be considered as an imagination of ringing voice from cellular phone. The risk was also compared between urban and rural, male and female and adult and children population. The information was gathered through well designed questionnaires for cellular user’s demographic and social characteristics, adopted safety measures and calling duration. Prevalence of “Ringing Delusion” among rural users was higher than the urban users. A trend for the risk was also observed in male users in comparison to female. Study may support innovators to re-examine health effects of mobile phones.展开更多
We propose a four-step phase cycling scheme that can cancel ringings from both the excitation and the refocusing pulses in Carr-Purcell-Meiboom-Gill(CPMG)measurements.It allows accurate measurements of the first echo ...We propose a four-step phase cycling scheme that can cancel ringings from both the excitation and the refocusing pulses in Carr-Purcell-Meiboom-Gill(CPMG)measurements.It allows accurate measurements of the first echo with short echo spacing tE,yielding improved precision of porosity,permeability,and fluid type identification in porous media study,at a cost of~25%signal reduction.In our example,we achieved tE=100 ms on a 6.8 MHz unilateral NMR sensor without using a Q-switch.These methods can be integrated in all nuclear magnetic resonance(NMR)protocols using CPMG,such as relaxation(T1,T2)and diffusion measurements,and do not require additional hardware(e.g.,Qswitches)to cancel ringing(although it can be used with a Q-switch to further reduce residual ringing).展开更多
A LAPTOP, a broadband connection and a pile of express delivery orders are all clues that 26-year-old Qu Wen was no longer a member of the nine-to-five white collar brigade. Three years after graduating, 0u now manage...A LAPTOP, a broadband connection and a pile of express delivery orders are all clues that 26-year-old Qu Wen was no longer a member of the nine-to-five white collar brigade. Three years after graduating, 0u now manages an online store on Taobao, China＇s fast-growing online shopping bazaar, selling handbags, cosmetics, accessories and other goods. Her online store now has three employees, and daily turnover surpassing 10,000 yuan （$1.612）. Last year. the entrepreneur also opened a retail outlet in her hometown in Shandong Province.展开更多
It＇s just been over half a year since Kenya inaugurated its standard gauge railway, but already the transport system is seeing heavy demand from travelers between Nairobi and Mombasa.
Sales show that Chinese mobile phone manufacturers have dialed into what African consumers really need by Gui Gui WHEN Guan Yazhou visited Tanzania’s Kariakoo market for the first time in late 2009,he couldn’t help ...Sales show that Chinese mobile phone manufacturers have dialed into what African consumers really need by Gui Gui WHEN Guan Yazhou visited Tanzania’s Kariakoo market for the first time in late 2009,he couldn’t help but be impressed.Today,the 29-year-old mobile phone engineer can still remember how surprised he was at seeing the extent to which Tecno,a Chinese mobile phone brand,had blanketed the area in advertising material.展开更多
China＇s Xinhua News Agency calls it the ＂biggest government reshuffle in years＂ in what is seen as a dra matic continuation of the previous seven rounds of cabinet restructuring that began in 1982.
Understanding migration patterns and spatial connectivity is crucial for conserving long-distance migratory birds. While satellite telemetry has advanced the study of large gulls, Pallas's Gull (Ichthyaetus ichthy...Understanding migration patterns and spatial connectivity is crucial for conserving long-distance migratory birds. While satellite telemetry has advanced the study of large gulls, Pallas's Gull (Ichthyaetus ichthyaetus) remains relatively understudied, with limited data on its migration routes and habitat use, particularly in Central Asia. This study integrates 684 ring recoveries (1968–2024) and GPS tracking data to analyze the migration ecology of individuals breeding at Alakol Lake, Kazakhstan. Ring recoveries confirm migratory connectivity across Kazakhstan, Russia, Uzbekistan, Turkmenistan, Iran, and Pakistan, with wintering records as far as India, Kuwait, Bangladesh, and Ethiopia. GPS tracking of a single individual (June 2020–August 2021) revealed a migration route from Alakol Lake to the Arabian Sea, with key stopovers at Zaisan Lake, Balkhash Lake, the Aral Sea, Aydar Lake, and the Amu Darya River. Notably, a post-breeding northward dispersal to Zaisan Lake and southern Russia was identified before the southward migration commenced. These findings highlight the significance of Kazakhstan's lakes as breeding and migratory hubs and the need to protect critical stopover sites in Central Asia. Given increasing anthropogenic pressures on wetland habitats, this research provides essential baseline data for conservation planning and enhances the broader understanding of gull migration ecology.展开更多
The ringing phenomenon has been studied in optical whispering gallery mode(WGM)resonators and can be used to sense the ultrafast process in spectroscopy.Here we observe the ringing phenomenon in a magnomechanical syst...The ringing phenomenon has been studied in optical whispering gallery mode(WGM)resonators and can be used to sense the ultrafast process in spectroscopy.Here we observe the ringing phenomenon in a magnomechanical system for the first time,which is induced by the interference between the microwave photons converted from the damped phonons and the probing microwave photons.This interference eventually appears as a transparency window even along with the ringing phenomenon in the measured microwave reflection spectrum,which is influenced by the scanning speed and the input power.Then,the ringing spectroscopy is used to measure the coupling strength between the magnon and phonon modes,and outline the displacement profile of𝑆1,2,2 mechanical mode in a YIG microsphere,demonstrating the theoretical analysis.In addition,the ring-up spectroscopy is developed in our magnomechanical system,laying the foundation for fast sensing based on mechanical motion.展开更多
随着人工智能大模型训练与推理业务的快速发展,智算中心面临算网协同调度的新挑战。为优化分布式智算Ring Allreduce业务的部署问题,首先,通过扩展传统波平面,开发了算力波平面技术,实现了算力与网络资源的一体化虚拟管理。然后,基于算...随着人工智能大模型训练与推理业务的快速发展,智算中心面临算网协同调度的新挑战。为优化分布式智算Ring Allreduce业务的部署问题,首先,通过扩展传统波平面,开发了算力波平面技术,实现了算力与网络资源的一体化虚拟管理。然后,基于算力波平面,提出了一种高效路由、波长、算力和时隙分配(routing,wavelength,computing power and time slot assignment,RWCTA)算法用于环规约(Ring Allreduce)业务部署。仿真结果表明,与传统基于波平面的部署算法相比,基于算力波平面的RWCTA算法能有效降低62.4%的总业务完成时间和54.5%的平均业务计算时间。展开更多
We describe here the characteristic features of the ringing we observed following large PMT signals in the Daya Bay reactor antineutrino experiment. We conclude that the ceramic capacitors used in the circuitry of the...We describe here the characteristic features of the ringing we observed following large PMT signals in the Daya Bay reactor antineutrino experiment. We conclude that the ceramic capacitors used in the circuitry of the PMT bases and the HV-signal decouplers are the primary cause for this ringing. We present some possible schemes to reduce the ringing when replacing these ceramic capacitors is not feasible.展开更多
Increasing temperatures and severe droughts threaten forest vitality globally.Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts o...Increasing temperatures and severe droughts threaten forest vitality globally.Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts on the growth of tree species,likely driven by local climatic aridity,climate trends,edaphic conditions,and the climatic adaption of tree species.The ability of tree species to cope with changing climate and the effects of environmental variables on growth trends and growth-climate relationships across diverse bioclimatic regions are still poorly understood for many species.This study investigated radial growth trends,interannual growth variability,and growth-climate sensitivity of two dominant tree species,Pinus tabulaeformis(PT)and Pinus sylvestris var.mongolica(PS),across a broad climatic gradient with a variety of soil properties in temperate Northern China.Using a network of 83 tree ring chronologies(54 for PT and 29 for PS)from 1971 to 2010,we documented that both species maintained constant growth trends at wet sites,while both displayed rapid declines at dry sites.We reported the species-specific drivers of spatial heterogeneity in growth trends,interannual growth variability,and growth-climate relationships.Calculated climatic variables and soil properties were identified as the most critical factors affecting the growth trends and growth-climate relationships.However,climatic variables play more essential roles than soil properties in determining the spatial heterogeneity of the growth-climate relationship.Lower clay content and higher soil nutrient regimes can exacerbate the moisture-related susceptibility of tree growth.Our findings highlight that soil properties emerged as important modulating factors to predict the drought vulnerability of forests in addition to climatic variables.Considering the continued climate warmingdrying trend in the future,both pines will face a more severe growth decline and increase in drought vulnerability at drier sites with lower clayed soil or higher nutrient regimes.展开更多
In this study,we present a comprehensive evaluation of the magnetic field measurements from the Vector Field Magnetometer(VFM)aboard the recently launched Macao Science Satellite-1(MSS-1).One-year data from November 2...In this study,we present a comprehensive evaluation of the magnetic field measurements from the Vector Field Magnetometer(VFM)aboard the recently launched Macao Science Satellite-1(MSS-1).One-year data from November 2,2023,to November 1,2024,are considered.The MSS-1 flies with a low inclination(41°)and is designed to provide high-resolution magnetic field measurements,especially for monitoring the evolution of the South Atlantic Anomaly.Earlier studies confirmed the possibility of using MSS-1A data to model the Earth’s main magnetic field(e.g.,Jiang Y et al.,2024).Therefore,in this study we focus on the magnetic signatures related to the external field,which are primarily associated with magnetospheric and ionospheric currents.The global distributions of the magnetic residuals from MSS-1A show a pattern consistent with that derived from the European Space Agency’s Swarm A satellite.A statistical survey of the conjugated observations(withΔt<5 min andΔR<150 km)between the two satellites showed that the difference between their magnetic residuals is within±3 nanoteslas.By separating the magnetic residuals at the noon and midnight hours,we see that the MSS-1A data can effectively capture features of the magnetospheric and ionospheric currents,such as the magnetospheric ring current and ionospheric equatorial electrojet.Moreover,the magnetic residuals from MSS-1A show a diamagnetic effect caused by post-sunset equatorial plasma bubbles,which also suggests that the MSS-1A data have the potential to reveal the ionospheric structures.The comprehensive evaluations performed within this study demonstrate that the MSS-1A provides high-quality magnetic field data reaching the level of the Swarm satellite,which enables a deeper understanding of the modeling of Earth’s magnetic field as well as monitoring of the magnetic environment.展开更多
基金Project supported by the National Natural Science Foundation of China (No. 51078325)the State Key Lab of Subtropical Building Science,South China University of Technology,China
文摘From the case study of Evening Bell Ringing at Nanping Hill,one of the West Lake Cultural Landscapes in Hangzhou,China,we investigated the soundscape of a scenic area with a profound cultural background.First,we conducted the soundscape physical index of the area in both winter and spring seasons to analyze its objective graphical expression.Second,we focused on people's reactions to the soundscape in order to obtain a subjective evaluation of each component in the soundscape and integrated environment.Then,the relationship between the objective data and the subjective evaluation was analyzed.Finally,the impacts of the natural environment,history,and cultural factors on the evaluation of the Jingci Temple soundscape were studied.It was found that natural sounds,cultural sounds,and historic sounds were widely acclaimed in people's subjective feelings,which indicated the close relationships among historical and cultural background,soundscape,and natural environment.Thus,the conclusion was made that soundscape should be consistent with the local natural environment and the historical and cultural background.
基金funded by the Research Council of Norway through NFR 191204/V30
文摘Honji instability and ringing of offshore structrures are two different phenomena. Honji instability occurs at a circular cylinder in transverse periodic finite motion in a water tank. It is superposed on the streaming flow induced by the cylinder’s boundary layer. Its oscillation period is half of the period of the cylinder oscillation. Finite volume calculations of the filtered Navier-Stokes equations visualize the three-dimensional instability, where fluid particles transported by the circumferencial roll pairs exhibit a periodic mushroom-like pattern. Force is the same with and without the Honji instability. The large eddy simulation calculations for high Reynolds number support a drag coefficient in accordance with the Stokes-Wang solution below separation and conform with experimental measurements of the damping force on a harmonically oscillating cylinder. Ringing of offshore structures are vibrations which appear at natural frequencies and concern fatigue. It is generated by a higher harmonic force oscillating with frequency being 3-4 times the fundamental wave frequency. Together with a strong inertia load in phase with the incoming wave’s acceleration, a secondary load cycle appears in strong seas when the wave crest leaves the structure; this occurs about 1/4 wave period after the main force peak, it starts when the wave crest is about one cylinder radius behind the cylinder, lasts for about 15-20 percent of the wave period and has a magnitude up to 11 % of the peak-to-peak total force. It is a gravity effect and appears in strong irregular seas when kA > 0.18 and um/√gD > 0.4 (k wavenumber, A amplitude, um maximal wave induced velocity, g acceleration of gravity, D cylinder diameter).
文摘Ringing artifact degradations always appear in the deconvolution of geophysical data. To address this problem, we propose a postprocessing approach to suppress ringing artifacts that uses a novel anisotropic diffusion based on a stationary wavelet transform （SWT） algorithm. In this paper, we discuss the ringing artifact suppression problem and analyze the characteristics of the deconvolu- tion ringing artifact. The deconvolution data containing ringing artifacts are decomposed into different SWT sub- bands for analysis, and a new multiscale adaptive aniso- tropic filter is developed to suppress these degradations. Finally, we demonstrate the performance of the proposed method and describe the experiments in detail.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51879039 and 51490672)。
文摘This paper presents a numerical study on the high-frequency wave loads and ringing response of offshore wind turbine foundations exposed to moderately steep transient water waves.Input wave groups are generated by the technique of frequency-focusing,and the numerical simulation of focused waves is based on the NewWave model and a Fourier time-stepping procedure.The proposed model is validated by comparison with the published laboratory data.In respect of both the wave elevations and the underlying water particle kinematics,the numerical results are in excellent agreement with the experimental data.Furthermore,the local evolution of power spectra and the transfer of energy into higher frequencies can be clearly identified.Then the generalized FNV theory and Rainey’s model are applied respectively to calculate the nonlinear wave loads on a bottom-hinged vertical cylinder in focused waves.Resonant ringing response excited by the nonlinear high-frequency wave loads is found in the numerical simulation when frequency ratios(natural frequency of the structure to peak frequency of wave spectra)are equal to 3–5.Dynamic amplification factor of ringing response is also investigated for different dynamic properties(natural frequency and damping ratio)of the structure.
基金National Natural Science Foundation of China under Grant No.10573004
文摘We investigate the evolution of an electromagnetic field in the spacetime of a stringy black hole.The objectpicture of the quasinormal ringing has been obtained by the finite difference method.Compared with a Schwarzschildblack hole,the results show that the electromagnetic field damps more slowly for a stringy black hole.
文摘The exponential application of mobile technology has led to a concern about implications of electromagnetic radiation on human health. As we are aware that mobile phone radiates EMR when users communicate to others and that time subscribers of the device are regularly exposed nearby 40% - 50% of total mobile irradiation. We analyzed the risk of "Ringing Delusion" among normal users, moderate users and heavy users when compared to low users. Although the "Ringing Delusion" has not been added in medical terminology but we found frequently such kind of symptoms among mobile phone users. "Ringing Delusion" may be considered as an imagination of ringing voice from cellular phone. The risk was also compared between urban and rural, male and female and adult and children population. The information was gathered through well designed questionnaires for cellular user’s demographic and social characteristics, adopted safety measures and calling duration. Prevalence of “Ringing Delusion” among rural users was higher than the urban users. A trend for the risk was also observed in male users in comparison to female. Study may support innovators to re-examine health effects of mobile phones.
基金We appreciate many helpful discussions with Martin Hürlimann at Schlumberger-Doll Research.We thank Dr.Isik Kizilyalli,program director of the Advanced Research Projects Agency-Energy(ARPA-E),for the partial support of this research under contract DE-AR0001063.
文摘We propose a four-step phase cycling scheme that can cancel ringings from both the excitation and the refocusing pulses in Carr-Purcell-Meiboom-Gill(CPMG)measurements.It allows accurate measurements of the first echo with short echo spacing tE,yielding improved precision of porosity,permeability,and fluid type identification in porous media study,at a cost of~25%signal reduction.In our example,we achieved tE=100 ms on a 6.8 MHz unilateral NMR sensor without using a Q-switch.These methods can be integrated in all nuclear magnetic resonance(NMR)protocols using CPMG,such as relaxation(T1,T2)and diffusion measurements,and do not require additional hardware(e.g.,Qswitches)to cancel ringing(although it can be used with a Q-switch to further reduce residual ringing).
文摘A LAPTOP, a broadband connection and a pile of express delivery orders are all clues that 26-year-old Qu Wen was no longer a member of the nine-to-five white collar brigade. Three years after graduating, 0u now manages an online store on Taobao, China＇s fast-growing online shopping bazaar, selling handbags, cosmetics, accessories and other goods. Her online store now has three employees, and daily turnover surpassing 10,000 yuan （$1.612）. Last year. the entrepreneur also opened a retail outlet in her hometown in Shandong Province.
文摘It＇s just been over half a year since Kenya inaugurated its standard gauge railway, but already the transport system is seeing heavy demand from travelers between Nairobi and Mombasa.
文摘Sales show that Chinese mobile phone manufacturers have dialed into what African consumers really need by Gui Gui WHEN Guan Yazhou visited Tanzania’s Kariakoo market for the first time in late 2009,he couldn’t help but be impressed.Today,the 29-year-old mobile phone engineer can still remember how surprised he was at seeing the extent to which Tecno,a Chinese mobile phone brand,had blanketed the area in advertising material.
文摘China＇s Xinhua News Agency calls it the ＂biggest government reshuffle in years＂ in what is seen as a dra matic continuation of the previous seven rounds of cabinet restructuring that began in 1982.
基金funded by the Ministry of Science and Higher Education of the Republic of Kazakhstan,the Scientific Program BR21882199–Cadastre of wild animals of arid territories of the Balkhash-Alakol basin with an assessment of threats for their conservation and sustainable use.
文摘Understanding migration patterns and spatial connectivity is crucial for conserving long-distance migratory birds. While satellite telemetry has advanced the study of large gulls, Pallas's Gull (Ichthyaetus ichthyaetus) remains relatively understudied, with limited data on its migration routes and habitat use, particularly in Central Asia. This study integrates 684 ring recoveries (1968–2024) and GPS tracking data to analyze the migration ecology of individuals breeding at Alakol Lake, Kazakhstan. Ring recoveries confirm migratory connectivity across Kazakhstan, Russia, Uzbekistan, Turkmenistan, Iran, and Pakistan, with wintering records as far as India, Kuwait, Bangladesh, and Ethiopia. GPS tracking of a single individual (June 2020–August 2021) revealed a migration route from Alakol Lake to the Arabian Sea, with key stopovers at Zaisan Lake, Balkhash Lake, the Aral Sea, Aydar Lake, and the Amu Darya River. Notably, a post-breeding northward dispersal to Zaisan Lake and southern Russia was identified before the southward migration commenced. These findings highlight the significance of Kazakhstan's lakes as breeding and migratory hubs and the need to protect critical stopover sites in Central Asia. Given increasing anthropogenic pressures on wetland habitats, this research provides essential baseline data for conservation planning and enhances the broader understanding of gull migration ecology.
基金supported by the National Key Research and Development Program of China(2020YFB2205801)Innovation program for Quantum Science and Technology(2021ZD0303203)+2 种基金National Natural Science Foundation of China(11934012,11874342 and 92050109)USTC Research Funds of the Double First-Class Initiative(YD2470002002)the Fundamental Research Funds for the Central Universities.
文摘The ringing phenomenon has been studied in optical whispering gallery mode(WGM)resonators and can be used to sense the ultrafast process in spectroscopy.Here we observe the ringing phenomenon in a magnomechanical system for the first time,which is induced by the interference between the microwave photons converted from the damped phonons and the probing microwave photons.This interference eventually appears as a transparency window even along with the ringing phenomenon in the measured microwave reflection spectrum,which is influenced by the scanning speed and the input power.Then,the ringing spectroscopy is used to measure the coupling strength between the magnon and phonon modes,and outline the displacement profile of𝑆1,2,2 mechanical mode in a YIG microsphere,demonstrating the theoretical analysis.In addition,the ring-up spectroscopy is developed in our magnomechanical system,laying the foundation for fast sensing based on mechanical motion.
文摘随着人工智能大模型训练与推理业务的快速发展,智算中心面临算网协同调度的新挑战。为优化分布式智算Ring Allreduce业务的部署问题,首先,通过扩展传统波平面,开发了算力波平面技术,实现了算力与网络资源的一体化虚拟管理。然后,基于算力波平面,提出了一种高效路由、波长、算力和时隙分配(routing,wavelength,computing power and time slot assignment,RWCTA)算法用于环规约(Ring Allreduce)业务部署。仿真结果表明,与传统基于波平面的部署算法相比,基于算力波平面的RWCTA算法能有效降低62.4%的总业务完成时间和54.5%的平均业务计算时间。
基金Supported by Ministry of Science and Technology of People’s Republic of China (2006CB808102)United States Department of Energy (DE-AC02-05CH11231, DE-FG02-94ER40840)
文摘We describe here the characteristic features of the ringing we observed following large PMT signals in the Daya Bay reactor antineutrino experiment. We conclude that the ceramic capacitors used in the circuitry of the PMT bases and the HV-signal decouplers are the primary cause for this ringing. We present some possible schemes to reduce the ringing when replacing these ceramic capacitors is not feasible.
基金funded by the National Key Research and Development Plan of China(No.2022YFE0127900)the National Natural Science Foundation of China(Nos.32071558,32171559)+2 种基金the Natural Science Foundation Key Project of Inner Mongolia Autonomous Region,China(No.2023ZD23)the Hulunbuir Science and Technology Plan Project(No.SF2022001)the Fundamental Research Funds of CAF(CAFYBB2023ZA002).
文摘Increasing temperatures and severe droughts threaten forest vitality globally.Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts on the growth of tree species,likely driven by local climatic aridity,climate trends,edaphic conditions,and the climatic adaption of tree species.The ability of tree species to cope with changing climate and the effects of environmental variables on growth trends and growth-climate relationships across diverse bioclimatic regions are still poorly understood for many species.This study investigated radial growth trends,interannual growth variability,and growth-climate sensitivity of two dominant tree species,Pinus tabulaeformis(PT)and Pinus sylvestris var.mongolica(PS),across a broad climatic gradient with a variety of soil properties in temperate Northern China.Using a network of 83 tree ring chronologies(54 for PT and 29 for PS)from 1971 to 2010,we documented that both species maintained constant growth trends at wet sites,while both displayed rapid declines at dry sites.We reported the species-specific drivers of spatial heterogeneity in growth trends,interannual growth variability,and growth-climate relationships.Calculated climatic variables and soil properties were identified as the most critical factors affecting the growth trends and growth-climate relationships.However,climatic variables play more essential roles than soil properties in determining the spatial heterogeneity of the growth-climate relationship.Lower clay content and higher soil nutrient regimes can exacerbate the moisture-related susceptibility of tree growth.Our findings highlight that soil properties emerged as important modulating factors to predict the drought vulnerability of forests in addition to climatic variables.Considering the continued climate warmingdrying trend in the future,both pines will face a more severe growth decline and increase in drought vulnerability at drier sites with lower clayed soil or higher nutrient regimes.
基金supported by the National Natural Science Foundation of China(Grant Nos.42474200 and 42174186)Chao Xiong is supported by the Dragon 6 cooperation 2024-2028(Project No.95437).
文摘In this study,we present a comprehensive evaluation of the magnetic field measurements from the Vector Field Magnetometer(VFM)aboard the recently launched Macao Science Satellite-1(MSS-1).One-year data from November 2,2023,to November 1,2024,are considered.The MSS-1 flies with a low inclination(41°)and is designed to provide high-resolution magnetic field measurements,especially for monitoring the evolution of the South Atlantic Anomaly.Earlier studies confirmed the possibility of using MSS-1A data to model the Earth’s main magnetic field(e.g.,Jiang Y et al.,2024).Therefore,in this study we focus on the magnetic signatures related to the external field,which are primarily associated with magnetospheric and ionospheric currents.The global distributions of the magnetic residuals from MSS-1A show a pattern consistent with that derived from the European Space Agency’s Swarm A satellite.A statistical survey of the conjugated observations(withΔt<5 min andΔR<150 km)between the two satellites showed that the difference between their magnetic residuals is within±3 nanoteslas.By separating the magnetic residuals at the noon and midnight hours,we see that the MSS-1A data can effectively capture features of the magnetospheric and ionospheric currents,such as the magnetospheric ring current and ionospheric equatorial electrojet.Moreover,the magnetic residuals from MSS-1A show a diamagnetic effect caused by post-sunset equatorial plasma bubbles,which also suggests that the MSS-1A data have the potential to reveal the ionospheric structures.The comprehensive evaluations performed within this study demonstrate that the MSS-1A provides high-quality magnetic field data reaching the level of the Swarm satellite,which enables a deeper understanding of the modeling of Earth’s magnetic field as well as monitoring of the magnetic environment.
