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Comparison of Simulated Backgrounds with In-orbit Observations for HXI Onboard ASO-S
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作者 Hao-Xiang Wang Zhe Zhang +4 位作者 Wei Liu Xian-Kai Jiang Deng-Yi Chen Yi-Ming Hu Yang Su 《Research in Astronomy and Astrophysics》 2025年第3期141-153,共13页
The Hard X-ray Imager(HXI)payload,a component of China’s Advanced Space-based Solar Observatory satellite,is designed to observe solar X-ray emissions in the 30-200 keV range,with the aim of investigating nonthermal ... The Hard X-ray Imager(HXI)payload,a component of China’s Advanced Space-based Solar Observatory satellite,is designed to observe solar X-ray emissions in the 30-200 keV range,with the aim of investigating nonthermal physical processes during solar flares.Before launch,Geant4 simulations were employed to assess the onorbit background of the HXI instrument,evaluating its performance and potential to achieve its scientific objectives.This study addresses issues identified in previous simulations and conducts further analyses to examine the distribution of background counts across the 99 detectors.The results demonstrate alignment between simulations and observations at low and medium geomagnetic latitudes;however,challenges persist at high geomagnetic latitudes due to limitations in the current albedo photon model.This investigation provides insights into background sources from various particles,enhances understanding of space background characteristics,and offers guidance for background subtraction in imaging processes. 展开更多
关键词 instrumentation detectors-Sun X-rays gamma-rays-(cosmology )cosmic background radiation-gamma-rays diffuse background
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The collaborative cross mouse for studying the effect of host genetic background on memory impairments due to obesity and diabetes 被引量:1
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作者 Avia Paz Kareem Midlej +2 位作者 Osayd Zohud Iqbal MLone Fuad A.Iraqi 《Animal Models and Experimental Medicine》 2025年第1期126-141,共16页
Background:Over the past few decades,a threefold increase in obesity and type 2 diabetes(T2D)has placed a heavy burden on the health-care system and society.Previous studies have shown correlations between obesity,T2D... Background:Over the past few decades,a threefold increase in obesity and type 2 diabetes(T2D)has placed a heavy burden on the health-care system and society.Previous studies have shown correlations between obesity,T2D,and neurodegenera-tive diseases,including dementia.It is imperative to further understand the relation-ship between obesity,T2D,and cognitive deficits.Methods:This investigation tested and evaluated the cognitive impact of obesity and T2D induced by high-fat diet(HFD)and the effect of the host genetic background on the severity of cognitive decline caused by obesity and T2D in collaborative cross(CC)mice.The CC mice are a genetically diverse panel derived from eight inbred strains.Results:Our findings demonstrated significant variations in the recorded phenotypes across different CC lines compared to the reference mouse line,C57BL/6J.CC037 line exhibited a substantial increase in body weight on HFD,whereas line CC005 ex-hibited differing responses based on sex.Glucose tolerance tests revealed significant variations,with some lines like CC005 showing a marked increase in area under the curve(AUC)values on HFD.Organ weights,including brain,spleen,liver,and kidney,varied significantly among the lines and sexes in response to HFD.Behavioral tests using the Morris water maze indicated that cognitive performance was differentially affected by diet and genetic background.Conclusions:Our study establishes a foundation for future quantitative trait loci map-ping using CC lines and identifying genes underlying the comorbidity of Alzheimer's disease(AD),caused by obesity and T2D.The genetic components may offer new tools for early prediction and prevention. 展开更多
关键词 collaborative cross mouse DIABETES host genetic background memory impairments OBESITY
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Construction and characteristic analysis of background error covariance coupled with land surface temperature 被引量:1
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作者 Qihang Yang Yaodeng Chen +4 位作者 Luyao Qin Yuanbing Wang Deming Meng Xusheng Yan Xinyao Qian 《Atmospheric and Oceanic Science Letters》 2025年第3期7-12,共6页
Land surface temperature(LST)is the key variable in land-atmosphere interaction,having an important impact on weather and climate forecasting.However,achieving consistent analysis of LST and the atmosphere in assimila... Land surface temperature(LST)is the key variable in land-atmosphere interaction,having an important impact on weather and climate forecasting.However,achieving consistent analysis of LST and the atmosphere in assimilation is quite challenging.This is because there is limited knowledge about the cross-component background error covariance(BEC)between LST and atmospheric state variables.This study aims to clarify whether there is a relationship between the error of LST and atmospheric variables,and whether this relationship varies spatially and temporally.To this end,the BEC coupled with atmospheric variables and LST was constructed(LST-BEC),and its characteristics were analyzed based on the 2023 mei-yu season.The general characteristics of LST-BEC show that the LST is mainly correlated with the atmospheric temperature and the correlation decreases gradually with a rise in atmospheric height,and the error standard deviation of the LST is noticeably larger than that of the low-level atmospheric temperature.The spatiotemporal characteristics of LST-BEC on the heavy-rain day and light-rain day show that the error correlation and error standard deviation of LST and low-level atmospheric temperature and humidity are closely related to the weather background,and also have obvious diurnal variations.These results provide valuable information for strongly coupled land-atmosphere assimilation. 展开更多
关键词 background error covariance Land surface temperature Error correlation Error standard deviation Data assimilation
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Association of the glycemic background patterns and the diabetes management efficacy in poorly controlled type 2 diabetes
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作者 Ayşe N Erbakan Müzeyyen Arslan Bahadır +6 位作者 FatoşN Kaya Büşra Güleç MiraçVural Keskinler Ümmügülsüm AktemurÇelik Özge Faydalıel Banu Mesçi Aytekin Oğuz 《World Journal of Diabetes》 SCIE 2025年第1期74-90,共17页
BACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2DM)is a major public health problem and a significant risk factor for the progression of diabetic complications.AIM To evaluate the effects of ... BACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2DM)is a major public health problem and a significant risk factor for the progression of diabetic complications.AIM To evaluate the effects of intensive and supportive glycemic management strategies over a 12-month period in individuals with T2DM with glycated hemoglobin(HbA1c)≥10%and varying backgrounds of glycemic control.METHODS This prospective observational study investigated glycemic control in patients with poorly controlled T2DM over 12 months.Participants were categorized into four groups based on prior glycemic history:Newly diagnosed,previously well controlled with recent worsening,previously off-target but now worsening,and HbA1c consistently above 10%.HbA1c levels were monitored quarterly,and patients received medical,educational,and dietary support as needed.The analysis focused on the success rates of good glycemic control and the associated factors within each group.RESULTS The study showed significant improvements in HbA1c levels in all participants.The most significant improvement was observed in individuals newly diagnosed with diabetes:65%achieved an HbA1c target of≤7%.The results varied between participants with different glycemic control histories,followed by decreasing success rates:39%in participants with previously good glycemic control,21%in participants whose glycemic control had deteriorated compared to before,and only 10%in participants with persistently poor control,with mean HbA1c levels of 6.3%,7.7%,8.2%,and 9.7%,respectively.After one year,65.2%of the“newly diagnosed patients”,39.3%in the“previously controlled group”,21.9%in the“previously off-target but now worsened'”group and 10%in the“poorly controlled from the start”group had achieved HbA1c levels of 7 and below.CONCLUSION In poorly controlled diabetes,the rate at which treatment goals are achieved is associated with the glycemic background characteristics,emphasizing the need for tailored strategies.Therefore,different and comprehensive treatment approaches are needed for patients with persistent uncontrolled diabetes. 展开更多
关键词 Type 2 diabetes mellitus Glycated hemoglobin Glycemic control Patient-centered care Diabetes management glycemic background
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Study on the Correction Method of Radiant Temperature Measurement of Turbine Blades Under the Background of High-Temperature Dynamics
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作者 Shengnan Liu Liwei Chen 《Instrumentation》 2025年第2期80-90,共11页
The turbine blades operate under high temperature and high pressure conditions,and when using radiation thermometry,the influence of radiation from surrounding blades leads to measurement errors.To address this issue,... The turbine blades operate under high temperature and high pressure conditions,and when using radiation thermometry,the influence of radiation from surrounding blades leads to measurement errors.To address this issue,this paper develops a three-dimensional discretized dynamic radiation transfer model based on the blade shape of the turbine.The relationship between the radiation angle coefficient of the surrounding blades and the rotation angle of the blade under test is analyzed.The radiation angle coefficient is calculated using the triangular element method,and temperature inversion is performed based on the effective emissivity to compute the measurement error.The results show that under dynamic high temperature conditions,the temperature measurement error caused by reflection at the selected 60%leaf height point varies with the rotation angle,and the maximum reaches 25.58K.The angular coefficient exhibits periodic fluctuations with changes in rotation angle,and the maximum effective emissivity increases as the rotation angle increases.As the blade height increases,the impact of reflected radiation on radiometric temperature measurement errors shows a decreasing trend.This study provides a reference for radiation thermometry in dynamic high-temperature environments. 展开更多
关键词 radiation temperature measurement dynamic background turbine blades effective emissivity ERROR
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Identification of QTL-by-environment interaction by controlling polygenic background effect
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作者 Fuping Zhao Lixian Wang Shizhong Xu 《Journal of Genetics and Genomics》 2025年第7期915-926,共12页
The quantitative trait loci(QTL)-by-environment(Q × E) interaction effect is hard to detect because there are no effective ways to control the genomic background. In this study, we propose a linear mixed model th... The quantitative trait loci(QTL)-by-environment(Q × E) interaction effect is hard to detect because there are no effective ways to control the genomic background. In this study, we propose a linear mixed model that simultaneously analyzes data from multiple environments to detect Q × E interactions. This model incorporates two different kinship matrices derived from the genome-wide markers to control both main and interaction polygenic background effects. Simulation studies demonstrate that our approach is more powerful than the meta-analysis and inclusive composite interval mapping methods. We further analyze four agronomic traits of rice across four environments. A main effect QTL is identified for 1000-grain weight(KGW), while no QTL are found for tiller number. Additionally, a large QTL with a significant Q × E interaction is detected on chromosome 7 affecting grain number, yield, and KGW. This region harbors two important genes, PROG1 and Ghd7. Furthermore, we apply our mixed model to analyze lodging in barley across six environments. The six regions exhibiting Q × E interaction effects identified by our approach overlap with the SNPs previously identified using EM and MCMC-based Bayesian methods, further validating the robustness of our approach. Both simulation studies and empirical data analyses show that our method outperforms all other methods compared. 展开更多
关键词 Q×E interaction Main effect META-ANALYSIS Mixed model Polygenic background
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High summer background O_(3)levels in the desert of northwest China
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作者 Xinbing Ren Fang Wang +8 位作者 Bayi Wu Shaoting Zhang Lei Zhang Xingjun Zhou Yuanzhe Ren Yongjing Ma Feng Hao Yongli Tian Jinyuan Xin 《Journal of Environmental Sciences》 2025年第5期516-528,共13页
Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentratio... Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentrations are relatively low.However,high summer background concentrations of about 100μg/m^(3)or 60 ppb were found in the Alxa Desert in the highland of northwest China based on continuous summer observations from 2019 to 2021,which was higher than the most of natural background areas or clean areas in world for summer O_(3)background concentrations.The high O_(3)background concentrations were related to surface features and altitude.Heavy-intensity anthropogenic activity areas in desert areas can cause increased O_(3)concentrations or pollution,but also generated O_(3)depleting substances such as nitrous oxide,which eventually reduced the regional O_(3)baseline values.Nitrogen dioxide(NO2)also had a dual effect on O_(3)generation,showing promotion at low concentrations and inhibition at high concentrations.In addition,sand-dust weather reduced O_(3)clearly,but O_(3)eventually stabilized around the background concentration values and did not vary with sand-dust particulate matter. 展开更多
关键词 Alxa Desert O_(3)background concentration Anthropogenic effect Sand-dust weather Northwest China
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A Preliminary Study on the Background of the Formation of the Meng Yao Zheng Dian
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作者 Hongying Wu Bao Long 《Journal of Clinical and Nursing Research》 2025年第2期93-101,共9页
Meng Yao Zheng Dian is one of the three classics of Mongolian medicine.It was written by Zhanbra Dorje,who was a famous Mongolian physician.The book was not only related to the author's origin,education and learni... Meng Yao Zheng Dian is one of the three classics of Mongolian medicine.It was written by Zhanbra Dorje,who was a famous Mongolian physician.The book was not only related to the author's origin,education and learning experience,but also closely related to the social development,cultural exchanges between Mongolian and Tibetan,and people's demand for Mongolian medicine at that time.The book in four languages indicates the name of Mongolian medicinal herbs,Mongolian of China,Tibetan of China,Chinese,Manchu medicine academic and cultural exchanges played a positive role in promoting the cultural exchanges,is a vivid embodiment of the cultural exchanges between Chinese nationalities and exchanges and mingling. 展开更多
关键词 Zhanbra Dorje Meng Yao Zheng Dian background of the book
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Rogue waves on a periodic background in the reduced Maxwell–Bloch system
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作者 YiJie Zhao Zhaqilao Niqi Ao 《Communications in Theoretical Physics》 2025年第8期25-34,共10页
In this paper,the nonlinearization of the Lax pair and the Darboux transformation method are used to construct the rogue wave on the elliptic function background in the reduced Maxwell–Bloch system,which is described... In this paper,the nonlinearization of the Lax pair and the Darboux transformation method are used to construct the rogue wave on the elliptic function background in the reduced Maxwell–Bloch system,which is described by four component nonlinear evolution equations(NLEEs).On the background of the Jacobian elliptic function,we obtain the admissible eigenvalues and the corresponding non-periodic eigenfunctions of the model spectrum problem.Then,with the help of the one-fold Darboux transformation and two-fold Darboux transformation,rogue waves on a dn-periodic background and cn-periodic background are derived,respectively.Finally,the corresponding complex dynamical properties and evolutions of the four components are illustrated graphically by choosing suitable parameters. 展开更多
关键词 Jacobian elliptic function Darboux transformation reduced Maxwell–Bloch system rogue waves on a periodic background
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Interactions of the Background State and Eddies in Shaping Aleutian Low Variations
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作者 Nan LIN Tuantuan ZHANG +3 位作者 Qiaoling REN Ho-Nam CHEUNG Chang-Hoi HO Song YANG 《Advances in Atmospheric Sciences》 2025年第8期1548-1565,共18页
The Aleutian Low(AL)is a dominant feature of the mean circulation in the North Pacific during the winter season.The background stationary wave,air-sea interaction,and transient eddies over the North Pacific exert dist... The Aleutian Low(AL)is a dominant feature of the mean circulation in the North Pacific during the winter season.The background stationary wave,air-sea interaction,and transient eddies over the North Pacific exert distinct impacts on the interannual variations of the AL intensity and position.In this study,we adopt the quasi-geostrophic geopotential tendency equation to investigate the roles of various physical processes in the maintenance and interannual variations of this system.The results show that absolute vorticity advection plays the most important role in the formation and maintenance of AL intensity,while high-frequency transient eddies contribute most to the meridional and zonal shifts of the AL.The high-frequency transient eddy vorticity forcing affects the AL through the barotropic energy conversion process,and,in turn,the AL enhances the high-frequency transient eddies through the baroclinic energy conversion process,forming a positive feedback.The associated high-frequency eddy kinetic energy anomalies exhibit an eastward movement toward the east coast of North America in the years of an intensified AL,which explains why a strengthened AL is often accompanied by an eastward movement.Furthermore,the energy conversion terms of high-frequency transient eddies are mostly located over the extratropical eastern North Pacific,leading to asymmetric features in the zonal movement of the AL. 展开更多
关键词 Aleutian Low interannual variations interactions between eddies and the background flow
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Gravitational Wave Background from Extreme-Mass-Ratio Inspirals
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作者 Haoyu Zhao Yuanhao Zhang +1 位作者 Xilong Fan Wenbiao Han 《Chinese Physics Letters》 2025年第5期239-247,共9页
The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary ta... The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary target for the space-based detector laser interferometer space antenna due to their long-lived signals and high signal-to-noise ratios. This study explores the statistical properties of the GWB from EMRI, focusing on the calculation methods for the GWB, the astrophysical distribution of EMRI sources, and the influence of key parameters, including the spin of supermassive black holes(SMBHs) and the masses of compact objects(COs). By analyzing these factors, we determine the distribution range of the characteristic strain of the GWB from EMRIs. We find that the final eccentricity distributions appear to have negligible effect on the intensity of the GWB due to rapid circularization before they become detectable and the spin of the SMBH enhances the gravitational wave characteristic strain by approximately 1% compared to cases without spin effects. The masses of COs can also significantly affect the characteristic strain of the GWB from EMRIs, with black hole as CO producing a gravitational wave signal intensity that is approximately one order of magnitude higher compared to cases where neutron star or white dwarf are the COs. 展开更多
关键词 probing astrophysical dynamical processes galactic centers astrophysical distribution extreme mass ratio inspirals laser interferometer space antenna gravitational wave background calculation methods characteristic strain Laser Interferometer Space Antenna
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The CCD instrument background of the SMILE SXI 被引量:2
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作者 M.W.J.Hubbard O.Hetherington +6 位作者 D.J.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay 《Earth and Planetary Physics》 EI CSCD 2024年第1期15-24,共10页
The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrou... The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is high.The shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen Belts.Therefore,two radiation environments can be approximated based on the shutter door position:open and closed.The instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two environments.Due to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two extremes.The results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar maxima.This is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes. 展开更多
关键词 instrument background X-ray astronomy space radiation
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STABILITY OF TRANSONIC SHOCKS TO THE EULER-POISSON SYSTEM WITH VARYING BACKGROUND CHARGES
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作者 Yang CAO Yuanyuan XING Na ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1487-1506,共20页
This paper is devoted to studying the stability of transonic shock solutions to the Euler-Poisson system in a one-dimensional nozzle of finite length.The background charge in the Poisson equation is a piecewise consta... This paper is devoted to studying the stability of transonic shock solutions to the Euler-Poisson system in a one-dimensional nozzle of finite length.The background charge in the Poisson equation is a piecewise constant function.The structural stability of the steady transonic shock solution is obtained by the monotonicity argument.Furthermore,this transonic shock is proved to be dynamically and exponentially stable with respect to small perturbations of the initial data.One of the crucial ingredients of the analysis is to establish the global well-posedness of a free boundary problem for a quasilinear second order equation with nonlinear boundary conditions. 展开更多
关键词 Euler-Poisson system transonic shock varying background charges STABILITY
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Hybrid rogue waves and breather solutions on the double-periodic background for the Kundu-DNLS equation
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作者 DongZhu Jiang Zhaqilao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第5期33-48,共16页
In this paper,by using the Darboux transformation(DT)method and the Taylor expansion method,a new nth-order determinant of the hybrid rogue waves and breathers solution on the double-periodic background of the Kundu-D... In this paper,by using the Darboux transformation(DT)method and the Taylor expansion method,a new nth-order determinant of the hybrid rogue waves and breathers solution on the double-periodic background of the Kundu-DNLS equation is constructed when n is even.Breathers and rogue waves can be obtained from this determinant,respectively.Further to this,the hybrid rogue waves and breathers solutions on the different periodic backgrounds are given explicitly,including the single-periodic background,the double-periodic background and the plane wave background by selecting different parameters.In addition,the form of the obtained solutions is summarized. 展开更多
关键词 double-periodic background hybrid rogue waves and breather darboux transformation Kundu-DNLS equation
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Rogue waves for the(2+1)-dimensional Myrzakulov–Lakshmanan-Ⅳ equation on a periodic background
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作者 Xiao-Hui Wang Zhaqilao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第4期32-42,共11页
In this paper, the rogue wave solutions of the(2+1)-dimensional Myrzakulov–Lakshmanan(ML)-Ⅳ equation, which is described by five component nonlinear evolution equations, are studied on a periodic background. By usin... In this paper, the rogue wave solutions of the(2+1)-dimensional Myrzakulov–Lakshmanan(ML)-Ⅳ equation, which is described by five component nonlinear evolution equations, are studied on a periodic background. By using the Jacobian elliptic function expansion method, the Darboux transformation(DT) method and the nonlinearization of the Lax pair, two kinds of rogue wave solutions which are expressed by Jacobian elliptic functions dn and cn, are obtained.The relationship between these five kinds of potential is summarized systematically. Firstly, the periodic rogue wave solution of one potential is obtained, and then the periodic rogue wave solutions of the other four potentials are obtained directly. The solutions we find present the dynamic phenomena of higher-order nonlinear wave equations. 展开更多
关键词 rogue waves on a periodic background (2+1)-dimensional Myrzakulov-Lakshmanan-IV equation Darboux transformation Jacobian elliptic function
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Characteristics of Lightning Activity in Southeast China and its Relation to the Atmospheric Background
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作者 支树林 朱杰 +1 位作者 刘岩 毛梦妮 《Journal of Tropical Meteorology》 SCIE 2024年第1期76-88,共13页
Based on the lightning observation data from the Fengyun-4A(FY-4A)Lightning Mapping Imager(FY-4A/LMI)and the Lightning Imaging Sensor(LIS)on the International Space Station(ISS),we extract the“event”type data as the... Based on the lightning observation data from the Fengyun-4A(FY-4A)Lightning Mapping Imager(FY-4A/LMI)and the Lightning Imaging Sensor(LIS)on the International Space Station(ISS),we extract the“event”type data as the lightning detection results.These observations are then compared with the cloud-to-ground(CG)lightning observation data from the China Meteorological Administration.This study focuses on the characteristics of lightning activity in Southeast China,primarily in Jiangxi Province and its adjacent areas,from April to September,2017–2022.In addition,with the fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis data,we further delved into the potential factors influencing the distribution and variations in lightning activity and their primary related factors.Our findings indicate that the lightning frequency and density of the FY-4A/LMI,ISS-LIS and CG data are higher in southern and central Jiangxi,central Fujian Province,and western and central Guangdong Province,while they tend to be lower in eastern Hunan Province.In general,the high-value areas of lightning density for the FY-4A/LMI are located in inland mountainous areas.The lower the latitude is,the higher the CG lightning density is.High-value areas of the CG lightning density are more likely to be located in eastern Fujian and southeastern Zhejiang Province.However,the high-value areas of lightning density for the ISS-LIS are more dispersed,with a scattered distribution in inland mountainous areas and along the coast of eastern Fujian.Thus,the mountainous terrain is closely related to the high-value areas of the lightning density.The locations of the high-value areas of the lightning density for the FY-4A/LMI correspond well with those for the CG observations,and the seasonal variations are also consistent.In contrast,the distribution of the high-value areas of the lightning density for the ISS-LIS is more dispersed.The positions of the peak frequency of the FY-4A/LMI lightning and CG lightning contrast with local altitudes,primarily located at lower altitudes or near mountainsides.K-index and convective available potential energy(CAPE)can better reflect the local boundary layer conditions,where the lightning density is higher and lightning seasonal variations are apparent.There are strong correlations in the annual variations between the dew-point temperature(Td)and CG lightning frequency,and the monthly variations of the dew-point temperature and CAPE are also strongly correlated with monthly variations of CG lightning,while they are weakly correlated with the lightning frequency for the FY-4A/LMI and ISS-LIS.This result reflects that the CAPE shows a remarkable effect on the CG lightning frequency during seasonal transitions. 展开更多
关键词 LIGHTNING satellite and ground detections atmospheric background Southeast China
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Comparative Analysis of Energy Characteristics of Two Southwest Vortices in Sichuan Under Similar Circulation Backgrounds
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作者 周春花 张驹 肖红茹 《Journal of Tropical Meteorology》 SCIE 2024年第2期168-179,共12页
Based on ERA5 reanalysis data,the present study analyzed the thermal energy development mechanism and kinetic energy conversion characteristics of two extreme rainstorm processes in relation to the shallow southwest v... Based on ERA5 reanalysis data,the present study analyzed the thermal energy development mechanism and kinetic energy conversion characteristics of two extreme rainstorm processes in relation to the shallow southwest vortex in the warm-sector during a“rain-generated vortex”process and the deep southwest vortex in a“vortex-generated rain”process.The findings were as follows:(1)During the extreme rainstorm on August 11,2020(hereinafter referred to as the“8·11”process),intense surface heating and a high-energy unstable environment were observed.The mesoscale convergence system triggered convection to produce heavy rainfall,and the release of latent condensation heat generated by the rainfall promoted the formation of a southwest vortex.The significant increase(decrease)in atmospheric diabatic heating and kinetic energy preceded the increase(decrease)in vorticity.By contrast,the extreme rainstorm on August 16,2020(hereinafter referred to as the“8·16”process)involved the generation of southwest vortex in a low-energy and highhumidity environment.The dynamic uplift of the southwest vortex triggered rainfall,and the release of condensation latent heat from rainfall further strengthened the development of the southwest vortex.The significant increase(decrease)in atmospheric diabatic heating and kinetic energy exhibited a delayed progression compared to the increase(decrease)in vorticity.(2)The heating effect around the southwest vortex region was non-uniform,and the heating intensity varied in different stages.In the“8·11”process,the heating effect was the strongest in the initial stage,but weakened during the vortex's development.On the contrary,the heating effect was initially weak in the“8·16”process,and intensified during the development stage.(3)The available potential energy of the“8·11”process significantly increased in kinetic energy converted from rotational and divergent winds through baroclinic action,and the divergent wind energy continued to convert into rotational wind energy.By contrast,the“8·16”process involved the conversion of rotational wind energy into divergent wind energy,which in turn converted kinetic energy back into available potential energy,thereby impeding the further development and maintenance of the southwest vortex. 展开更多
关键词 southwest vortex similar circulation background diabatic heating kinetic energy spatial non-uniform heating effect
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Gravitational Waves Background, as Well as Some UFO, FRB and Supernova Flares, Are Due to Compressibility of the Spacetime (CoST)
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作者 Evgeny A. Novikov 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期67-70,共4页
The recently observed gravitational wave background is explained in terms of the quantum modification of the general relativity (Qmoger). Some UFO, FRB and supernova flares also can be explained in terms of Qmoger.
关键词 Gravitational Wave background Quantum Modification of the General Relativity Compressibility of the Spacetime (CoST)
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Optimal Insurance with Background Risk under the Ambiguity and Belief Heterogeneity Structure
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作者 Xiaohan Wang 《Journal of Applied Mathematics and Physics》 2024年第6期2160-2171,共12页
In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal i... In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal insurance contract when maxing the insured’s expected utility of his/her remaining wealth under the smooth ambiguity model and the heterogeneous belief form satisfying the MHR condition. We calculate the insurance premium by using generalized Wang’s premium and also introduce a series of stochastic orders proposed by [1] to describe the relationships among the insurable risk, background risk and ambiguity parameter. We obtain the deductible insurance is the optimal insurance while they meet specific dependence structures. 展开更多
关键词 Optimal Insurance Monotone Hazard Ratio Order Smooth Ambiguity Model background Risk Belief Heterogeneity Structure
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Algorithms for Empirical Equations in Terms of the Cosmic Microwave Background Temperature
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作者 Tomofumi Miyashita 《Journal of Modern Physics》 2024年第10期1567-1585,共19页
Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature. Next, we propose an empirical equation for the fine-structure constant. Considering the compatibility among... Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature. Next, we propose an empirical equation for the fine-structure constant. Considering the compatibility among these empirical equations, the CMB temperature (Tc) and gravitational constant (G) were calculated to be 2.726312 K and 6.673778 × 10−11 m3∙kg−1∙s−2, respectively. Every equation can be explained numerically in terms of the Compton length of an electron (λe), the Compton length of a proton (λp) and α. Furthermore, every equation can also be explained in terms of the Avogadro number and the number of electrons at 1 C. We show that every equation can be described in terms of the Planck constant. Then, the ratio of the gravitational force to the electric force can be uniquely determined with the assumption of minimum mass. In this report, we describe the algorithms used to explain these equations in detail. Thus, there are no dimension mismatch problems. 展开更多
关键词 Temperature of the Cosmic Microwave background Minimum Mass The Ratio of Gravitational Force to Electric Force Dimension Analysis Redefinition Method Fine Structure Constant
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