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Forecast errors of tropical cyclone track and intensity by the China Meteorological Administration from 2013 to 2022
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作者 Huanmujin Yuan Hong Wang +2 位作者 Yubin Li Kevin K.W.Cheung Zhiqiu Gao 《Atmospheric and Oceanic Science Letters》 2026年第1期72-77,共6页
This study presents a comprehensive evaluation of tropical cyclone(TC)forecast performance in the western North Pacific from 2013 to 2022,based on operational forecasts issued by the China Meteorological Administratio... This study presents a comprehensive evaluation of tropical cyclone(TC)forecast performance in the western North Pacific from 2013 to 2022,based on operational forecasts issued by the China Meteorological Administration.The analysis reveals systematic improvements in both track and intensity forecasts over the decade,with distinct error characteristics observed across various forecast parameters.Track forecast errors have steadily decreased,particularly for longer lead times,while error magnitudes have increased with longer forecast lead times.Intensity forecasts show similar progressive enhancements,with maximum sustained wind speed errors decreasing by 0.26 m/s per year for 120 h forecasts.The study also identifies several key patterns in forecast performance:typhoon-grade or stronger TCs exhibit smaller track errors than week or weaker systems;intensity forecasts systematically overestimate weaker TCs while underestimating stronger systems;and spatial error distributions show greater track inaccuracies near landmasses and regional intensity biases.These findings highlight both the significant advances in TC forecasting capability achieved through improved modeling and observational systems,and the remaining challenges in predicting TC changes and landfall behavior,providing valuable benchmarks for future forecast system development. 展开更多
关键词 Forecast error Tropical cyclone TRACK intensity
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Diagnosis of focal spots at relativistic intensity utilizing coherent radiation from laser-driven flying electron sheets
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作者 Shirui Xu Zhuo Pan +22 位作者 Ying Gao Jiarui Zhao Shiyou Chen Zhusong Mei Xun Chen Ziyang Peng Xuan Liu Yulan Liang Tianqi Xu Tan Song Qingfan Wu Yujia Zhang Zhipeng Liu Zihao Zhang Haoran Chen Qihang Han Jundong Shen Chenghao Hua Kun Zhu Yanying Zhao Chen Lin Xueqing Yan Wenjun Ma 《Matter and Radiation at Extremes》 2025年第2期16-23,共8页
Experimental validation of laser intensity is particularly important for the study of fundamental physics at extremely high intensities.However,reliable diagnosis of the focal spot and peak intensity faces huge challe... Experimental validation of laser intensity is particularly important for the study of fundamental physics at extremely high intensities.However,reliable diagnosis of the focal spot and peak intensity faces huge challenges.In this work,we demonstrate for the firs time that the coherent radiation farfiel patterns from laser–foil interactions can serve as an in situ,real-time,and easy-to-implement diagnostic for an ultraintense laser focus.The laser-driven electron sheets,curved by the spatially varying laser fiel and leaving the targets at nearly the speed of light,produce doughnut-shaped patterns depending on the shapes of the focal spot and the absolute laser intensities.Assisted by particle-in-cell simulations,we can achieve measurements of the intensity and the focal spot,and provide immediate feedback to optimize the focal spots for extremely high intensity. 展开更多
关键词 diagnosis focal spot peak intensity laser foil interactions laser fi coherent radiation farfiel patterns laser driven electron sheets experimental validation laser intensity focal spot coherent radiation
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ENGINet:End-to-end deep learning of the cumulative absolute velocity,Arias intensity,and spectrum intensity prediction for on-site earthquake early warning
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作者 Zhu Jingbao Li Shanyou Song Jindong 《Earthquake Engineering and Engineering Vibration》 2025年第4期943-957,I0002-I0096,共110页
One of the primary tasks of earthquake early warning(EEW)systems is to predict potential earthquake damage rapidly and accurately.Cumulative absolute velocity(CAV),Arias intensity(I_(A)),and spectrum intensity(SI)are ... One of the primary tasks of earthquake early warning(EEW)systems is to predict potential earthquake damage rapidly and accurately.Cumulative absolute velocity(CAV),Arias intensity(I_(A)),and spectrum intensity(SI)are important parameters for measuring ground motion intensity and assessing earthquake damage.Due to the limited available information in EEW,CAV,I_(A),and SI cannot be accurately predicted using traditional EEW methods.In this paper,we propose an end-to-end deep learning-based Ground motion Intensity prediction Network(ENGINet)for on-site EEW.The aim of the ENGINet is to predict CAV,I_(A),and SI rapidly and reliably.ENGINet is based on a convolutional neural network and recurrent neural network.The inputs of the network are three-component acceleration records,three-component velocity records,and three-component displacement records obtained by a single station.The results from the test dataset show that at 3 s after the P-wave arrival,compared with the baseline models and other traditional methods,ENGINet has better performance in predicting CAV,I_(A),and SI.Our results indicate that ENGINet can quickly and accurately predict CAV,I_(A),and SI to some extent and has good potential in EEW efforts. 展开更多
关键词 on-site earthquake early warning deep learning cumulative absolute velocity arias intensity spectrum intensity
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Assessment of seismic intensity and seismic performance of buildings in the M7.9 Myanmar earthquake 被引量:4
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作者 Sun Baitao Yan Jiaqi +2 位作者 Yang Yongqiang Chen Xiangzhao Sun Menghan 《Earthquake Engineering and Engineering Vibration》 2025年第3期641-652,共12页
Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field ... Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field surveys,and loss evaluations.The paper focuses on the intensity distribution and structural damage characteristics of the 2025 M7.9 Myanmar earthquake,yielding the following key findings.(1)The seismogenic fault rupture propagated in a nearly N-S direction,with a surface rupture length of approximately 450 km.The seismic impact zone exhibited an elongated N-S distribution and a shorter E-W span,distributed like a belt around the seismogenic fault.(2)Within the seismic impact zones,existing buildings comprised five primary structural types,with timber(bamboo)structures constituting the largest proportion(≈80%in rural areas,≈50%in urban areas).The relatively low disaster losses and casualties were primarily attributable to the good seismic performance and low damage ratio of timber(bamboo)structures across varying intensity zones.(3)An anomalous zone of intensityⅨwas located at the boundary between intensityⅥandⅦregions in Nay Pyi Taw.Here,ridge topography combined with soft soil layers significantly amplified ground motion,exacerbating structural damage.(4)Directional effects of ground motion were observed,with the structural damage phenomena and peak ground acceleration(PGA)values in the N-S direction exceeding those in the E-W direction.This validates that the maximum PGA distribution of strike-slip fault earthquakes aligns with the fault strike.The research is expected to provide technical support for post-disaster reconstruction planning,site selection,and disaster mitigation strategies in Myanmar. 展开更多
关键词 M7.9 Myanmar earthquake seismic intensity timber(bamboo)structure directional effects of ground motion strike-slip fault
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Do energy intensity,resource abundance and inequality drive energy poverty?Evidence from developing countries 被引量:1
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作者 Ashar Awan Mustafa Kocoglu +2 位作者 Mohammad Subhan Mohammed Shakib Nora Yusma bte Mohamed Yusoff 《Geoscience Frontiers》 2025年第3期119-136,共18页
Energy poverty in developing countries is a critical issue characterized by the lack of access to modern energy services,such as electricity and clean cooking facilities,as marked in SDG 7.This study explores the corr... Energy poverty in developing countries is a critical issue characterized by the lack of access to modern energy services,such as electricity and clean cooking facilities,as marked in SDG 7.This study explores the correlations between energy poverty,energy intensity,resource abundance,and income inequality,as these factors have been theorized to play important roles in influencing energy poverty in developing countries.By observing that the dataset is heterogeneous across the countries and over the time frame,we use the Method of Moments Quantile Regression(MMQR)to analyze our developing countries’data from 2000 to 2019.Our findings indicate that energy intensity is a significant factor influencing energy poverty,suggesting that higher energy consumption relative to the sample countries can exacerbate this issue.Additionally,we observe that income inequality within the sample countries is a critical determinant of energy poverty levels,highlighting the dynamics between economic disparity and access to energy resources.Interestingly,our study reveals that resource abundance acts as a blessing rather than a curse in terms of energy poverty,implying that countries rich in natural resources may have better opportunities to combat energy deprivation.Finally,we emphasize the vital role of financial markets in addressing energy poverty on a global scale,suggesting that robust financial systems can facilitate investments and innovations aimed at improving energy access for vulnerable populations.The results from the robustness analysis support the empirical results obtained from the main estimation.The empirical findings of the present study advance important comprehensions for policymakers to adopt energy policies that address the complex challenges of energy poverty and promote inclusive energy access. 展开更多
关键词 Energy poverty Natural Resources Energy intensity INEQUALITY Developing countries SDGs
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Seismic wave simulation of near-fault seismic intensity field for the 2025 Myanmar M_(w)7.7 earthquake constrained by mid-to far-field CENC seismic network data 被引量:1
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作者 Xie Zhinan Wang Shuai +4 位作者 Yuan Yangtao Zhang Wenyue Zhou Tianyu Ma Qiang Li Shanyou 《Earthquake Engineering and Engineering Vibration》 2025年第3期629-640,I0001,共13页
The 2025 M_(w)7.7 Myanmar earthquake highlighted the challenge of near-fault seismic intensity field reconstruction due to sparse seismic networks.To address this limitation,a framework was proposed integrating seismi... The 2025 M_(w)7.7 Myanmar earthquake highlighted the challenge of near-fault seismic intensity field reconstruction due to sparse seismic networks.To address this limitation,a framework was proposed integrating seismic wave simulation with a data-constrained finite-fault rupture model.The constraint is implemented by identifying the optimal ground motion models(GMMs)through a scoring system that selects the best-fit GMMs to mid-and far-field China Earthquake Networks Center(CENC)seismic network data;and applying the optimal GMMs to refine the rupture model parameters for near-fault intensity field simulation.The simulated near-fault seismic intensity field reproduces seismic intensities collected from Myanmar’s sparse seismic network and concentrated in≥Ⅷintensity zones within 50 km of the projected fault plane;and identifies abnormal intensity regions exhibiting≥Ⅹintensity along the Meiktila-Naypyidaw corridor and near Shwebo that are attributed to soft soil amplification effects and near-fault directivity.This framework can also be applied to post-earthquake assessments in other similar regions. 展开更多
关键词 seismic wave simulation sparse seismic networks ground motion models seismic intensity feld finite-fault rupture model
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Exercise intensity and the risk of end-stage renal disease in diabetes: A nationwide population-based study
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作者 Eun Hui Bae Sang Yup Lim +6 位作者 Bong-Seong Kim Kyung-Do Han Sang Heon Suh Hong Sang Choi Chang Seong Kim Seong Kwon Ma Soo Wan Kim 《World Journal of Diabetes》 2025年第7期152-166,共15页
BACKGROUND Exercise plays a key role in managing chronic conditions such as diabetes mellitus(DM),a major contributor to end-stage renal disease(ESRD),a serious public health issue.AIM To investigate the relationship ... BACKGROUND Exercise plays a key role in managing chronic conditions such as diabetes mellitus(DM),a major contributor to end-stage renal disease(ESRD),a serious public health issue.AIM To investigate the relationship between exercise intensity,DM duration,and ESRD incidence.METHODS This retrospective cohort study analyzed data from 2495031 individuals with DM who underwent the Korean National Health Screening between 2015 and 2016,with follow-up through 2022.The Cox proportional hazards model was adjusted for confounders,including age,sex,income,smoking,and baseline comorbidities.RESULTS Longer DM duration was associated with a significantly higher risk of ESRD,with durations≥10 years showing the highest risk[hazard ratio(HR):2.624,95%confidence interval(CI):2.486-2.770].Increased exercise intensity reduced the risk of developing ESRD across all diabetes duration groups,with the highest exercise category(≥1500 metabolic equivalents of task-min/week)demonstrating a protective effect compared to that of no exercise(HR:0.837,95%CI:0.791-0.886).Exercise benefits were more pronounced in patients without hypertension,non-smokers,and those with lower alcohol consumption.Additionally,ESRD risk reduction was significant among patients with a body mass index≥25 and those without proteinuria or chronic kidney disease.CONCLUSION Longer diabetes duration is associated with increased ESRD risk,while high-intensity exercise may mitigate this risk.These findings suggest promoting exercise is important for managing diabetes to reduce renal complications. 展开更多
关键词 EXERCISE Diabetes mellitus End-stage renal disease Chronic kidney disease intensity DURATION
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Short-Term Rolling Prediction of Tropical Cyclone Intensity Based on Multi-Task Learning with Fusion of Deviation-Angle Variance and Satellite Imagery
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作者 Wei TIAN Ping SONG +5 位作者 Yuanyuan CHEN Yonghong ZHANG Liguang WU Haikun ZHAO Kenny Thiam Choy LIM KAM SIAN Chunyi XIANG 《Advances in Atmospheric Sciences》 2025年第1期111-128,共18页
Tropical cyclones(TCs)are one of the most serious types of natural disasters,and accurate TC activity predictions are key to disaster prevention and mitigation.Recently,TC track predictions have made significant progr... Tropical cyclones(TCs)are one of the most serious types of natural disasters,and accurate TC activity predictions are key to disaster prevention and mitigation.Recently,TC track predictions have made significant progress,but the ability to predict their intensity is obviously lagging behind.At present,research on TC intensity prediction takes atmospheric reanalysis data as the research object and mines the relationship between TC-related environmental factors and intensity through deep learning.However,reanalysis data are non-real-time in nature,which does not meet the requirements for operational forecasting applications.Therefore,a TC intensity prediction model named TC-Rolling is proposed,which can simultaneously extract the degree of symmetry for strong TC convective cloud and convection intensity,and fuse the deviation-angle variance with satellite images to construct the correlation between TC convection structure and intensity.For TCs'complex dynamic processes,a convolutional neural network(CNN)is used to learn their temporal and spatial features.For real-time intensity estimation,multi-task learning acts as an implicit time-series enhancement.The model is designed with a rolling strategy that aims to moderate the long-term dependent decay problem and improve accuracy for short-term intensity predictions.Since multiple tasks are correlated,the loss function of 12 h and 24 h are corrected.After testing on a sample of TCs in the Northwest Pacific,with a 4.48 kt root-mean-square error(RMSE)of 6 h intensity prediction,5.78 kt for 12 h,and 13.94 kt for 24 h,TC records from official agencies are used to assess the validity of TC-Rolling. 展开更多
关键词 tropical cyclone intensity structure rolling prediction MULTI-TASK
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Bonding and anti-bonding orbitals stable electron intensity difference theory
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作者 Xiaobing Lan Hao Lu +5 位作者 Xusheng Wang Qing Li Dongdong Li Jun Chen Peng Wang Guangfu Liao 《Chinese Journal of Catalysis》 2025年第9期6-9,共4页
Surface chemistry plays a critical role in the fields of electrochemistry,heterogeneous catalysis,adsorption,etc.[1–4].The representative D-band center theory reported through Hammer and Nørskov in surface chemi... Surface chemistry plays a critical role in the fields of electrochemistry,heterogeneous catalysis,adsorption,etc.[1–4].The representative D-band center theory reported through Hammer and Nørskov in surface chemistry has been widely used in early studies to predict adsorption strength[5,6].Generally,the adsorption strength of active sites correlates inversely with the downward shift of the D-band center(εd)relative to the Fermi level,as lower-energy positioning increases anti-bonding orbital occupancy,weakening surface interactions(Fig.1(a)). 展开更多
关键词 anti bonding orbitals adsorption surface chemistry ELECTROCHEMISTRY heterogeneous catalysis electron intensity bonding orbitals electrochemistryheterogeneous catalysisadsorptionetc
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Interplay between physical activity volume and intensity with modeled life expectancy in women and men:A prospective cohort analysis
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作者 Francesco Zaccardi Alex V.Rowlands +12 位作者 Paddy C.Dempsey Cameron Razieh Joe Henson Jonathan Goldney Benjamin D.Maylor Atanu Bhattacharjee Yogini Chudasama Charlotte Edwardson Jari A.Laukkanen Ulf Ekelund Melanie J.Davies Kamlesh Khunti Thomas Yates 《Journal of Sport and Health Science》 2025年第1期6-15,共10页
Background There is a lack of research examining the interplay between objectively measured physical activity volume and intensity with life expectancy.The purpose of the study was to investigate the interplay between... Background There is a lack of research examining the interplay between objectively measured physical activity volume and intensity with life expectancy.The purpose of the study was to investigate the interplay between objectively measured PA volume and intensity profiles with modeled life expectancy in women and men within the UK Biobank cohort study and interpret findings in relation to brisk walking.Methods Individuals from UK Biobank with wrist-worn accelerometer data were included.The average acceleration and intensity gradient were extracted to describe the physical activity volume and intensity profile.Mortality data were obtained from national registries.Adjusted life expectancies were estimated using parametric flexible survival models.Results 40,953(57.1%)women(median age=61.9 years)and 30,820(42.9%)men(63.1 years)were included.Over a median follow-up of 6.9 years,there were 1719(2.4%)deaths(733 in women;986 in men).At 60 years,life expectancy was progressively longer for higher physical activity volume and intensity profiles,reaching 95.6 years in women and 94.5 years in men at the 90th centile for both volume and intensity,corresponding to 3.4 additional years(95%confidence interval(95%CI):2.4-4.4)in women and 4.6 additional years(95%CI:3.6-5.6)in men compared to those at the 10th centiles.An additional 10-min or 30-min daily brisk walk was associated with 0.9(95%CI:0.5-1.3)and 1.4 years(95%CI:0.9-1.9)longer life expectancy,respectively,in inactive women;and 1.4 years(95%CI:1.0-1.8)and 2.5(95%CI:1.9-3.1)in inactive men.Conclusion Higher physical activity volumes were associated with longer life expectancy,with a higher physical activity intensity profile further adding to a longer life.Adding as little as a 10-min brisk walk to daily activity patterns may result in a meaningful benefit to life expectancy. 展开更多
关键词 Life expectancy Physical activity intensity Physical activity volume Survival Walking
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Effect of comprehensive perioperative nursing on pain intensity,complication rates,and comfort levels in patients undergoing gallstone surgery
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作者 Chen-Yan Bao Xiao-Kun Ding +2 位作者 Qiao-Fei Qi Peng Ye Ze-Jun Fang 《World Journal of Gastrointestinal Surgery》 2025年第2期111-119,共9页
BACKGROUND Surgery is the gold standard for gallstone treatment.Nevertheless,the complications associated with the surgical procedure can exert diverse and adverse impacts on patients’health and quality of life to va... BACKGROUND Surgery is the gold standard for gallstone treatment.Nevertheless,the complications associated with the surgical procedure can exert diverse and adverse impacts on patients’health and quality of life to varying extents.Hence,it is essential to offer perioperative care to patients undergoing gallstone surgery.AIM To examine the impact of perioperative comprehensive nursing on pain intensity,complication rates,and patient comfort in individuals undergoing gallstone surgery.METHODS From February 2022 to February 2024,195 patients who underwent gallstone surgery at Sanmen People’s Hospital were selected and divided into two groups:A control group receiving routine nursing care(95 patients)and a research group receiving perioperative comprehensive nursing(100 patients).Key postoperative recovery indicators,including time to first postoperative anal exhaust,oral food intake,and ambulation,were observed,along with pain intensity(measured by the numeric rating scale),complication rate(bleeding,incision infection,recurrence),patient comfort(assessed using the visual analogue scale),and quality of life(measured by the World Health Organization Quality of Life-BREF).RESULTS The research group showed significantly shorter times to first postoperative anal exhaust,oral intake,and ambulation.Moreover,numeric rating scale pain scores in the research group were markedly lower post-nursing,and the total complication rate was significantly reduced compared to the control group.Furthermore,comfort levels improved considerably in the research group,and World Health Organization Quality of Life-BREF scores across the physical,psychological,social,and environmental domains were significantly higher compared to the control group following nursing care.CONCLUSION Perioperative comprehensive nursing effectively enhances postoperative recovery in patients undergoing gallstone surgery,reducing pain,lowering complications,and improving patient comfort and quality of life,which deserves clinical application. 展开更多
关键词 Perioperative comprehensive nursing Gallstone surgery Pain intensity Complication rate COMFORT
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Spatio-temporal dynamics and influencing factors of carbon emission intensity in China's agriculture sector
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作者 YIN Junfeng YE Sijing +1 位作者 SONG Changqing GAO Peichao 《Journal of Geographical Sciences》 2025年第11期2310-2334,共25页
Agriculture holds a pivotal position in the economic fabric of every nation,yet concerns about agricultural carbon emission intensity(ACI)have become a major hurdle to achieving global economic sustainability.Focusing... Agriculture holds a pivotal position in the economic fabric of every nation,yet concerns about agricultural carbon emission intensity(ACI)have become a major hurdle to achieving global economic sustainability.Focusing on 31 provincial-level regions in China,this study uses the Exploratory Spatio-temporal Data Analysis(ESTDA)and Panel Quantile Regression(PQR)model to analyze the spatio-temporal interaction characteristics and influencing factors of ACI in China from 2004 to 2023.The findings are as follows:(1)ACI showed an overall downward trend,and the spatial distribution pattern was characterized by“high in the western region and low along the southeastern coast”.Although the overall disparity tended to converge,some high-carbon-intensity regions exhibited extreme trends.ACI displayed clear spatial directionality,with the spatial center shifting steadily toward the northeast.(2)Regions in the northwest,northeast,and central-south parts exhibited strong local spatial structural dynamics,and the local spatial dependence of ACI in each region showed a nonlinear trend.Generally speaking,the spatial association pattern demonstrated a certain degree of inertia in spatial transfer,reflecting strong path dependence or spatial lock-in characteristics.(3)Optimization of industrial structure and improvement in agricultural mechanization will increase ACI,while economic development can effectively reduce it.The impact of urbanization on ACI exhibits a nonlinear pattern.The coordinated development of economic growth and urbanization significantly reduces ACI,with a stronger emission reduction observed in regions with low ACI.The optimization of industrial structure,when combined with urbanization and environmental regulation,contributes to significant emission reductions particularly in high-ACI areas.Similarly,the synergy between agricultural mechanization and urbanization effectively lowers emissions in low-ACI regions,though this effect diminishes in areas with higher ACI. 展开更多
关键词 agriculture sector carbon emission intensity spatio-temporal interaction influencing factors China
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Spatiotemporal Variation of Water Cycle Intensity in the Pamir Plateau from 1980 to 2019 and Its Climatic Drivers
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作者 Jingjing Zhang Lingxin Kong +3 位作者 Long Ma Majid Gulayozov Anvar Kodirov Jilili Abuduwaili 《Journal of Earth Science》 2025年第6期2748-2762,共15页
A comprehensive understanding of the hydrological cycle is essential for Earth system science and climate change research.The Water Cycle Intensity(WCI)is defined as the sum of precipitation and actual evapotranspirat... A comprehensive understanding of the hydrological cycle is essential for Earth system science and climate change research.The Water Cycle Intensity(WCI)is defined as the sum of precipitation and actual evapotranspiration within a landscape unit.It is a widely used metric to quantify the impact of climate change on the global distribution of water resources.The WCI in the Pamir Plateau,located at the heart of Asian Water Towers,has received little attention.Understanding this aspect is crucial for assessing the impact of climate change on the hydrological cycle and devising strategies to adapt to these changes.Our study assessed the spatiotemporal variation in WCI on the Pamir Plateau from 1980 to 2019 using the WCI framework.Additionally,we explored the teleconnection mechanisms linking the WCI with the Indian Ocean Dipole Mode Index(DMI),canonical El Niño-Southern Oscillation(ENSO),and El Niño Modoki(EMI)using the wavelet analysis method.The findings showed that the WCI of the Pamir Plateau experienced a statistically insignificant increase from 1980 to 2019,particularly after 2003.Spatially,the eastern Pamir Plateau WCI increased significantly,whereas the western region showed a non-significant downward trend.This study found that the WCI in the Pamir Plateau is significantly influenced by atmospheric circulation patterns,and the variation in the WCI in the Pamir Plateau is mainly affected by the canonical ENSO,as well as by the coupling effect of canonical ENSO,and EMI.In addition,based on the characteristics of the regional hydrological cycle,we developed water resource management policies targeting flood risks in the northern Pamir Plateau and drought trends in the southwestern region.These insights not only deepen our understanding of changes in terrestrial hydrological cycles and their underlying mechanisms under climate change but also provide important references for water resource management in the mountainous regions of Central Asia. 展开更多
关键词 water cycle intensity wavelet analysis Pamir Plateau Large scale circulation Central Asia climate change water resources
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Fine-Grained Point Cloud Intensity Correction Modeling Method Based on Mobile Laser Scanning
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作者 Xu Liu Qiujie Li +3 位作者 Youlin Xu Musaed Alhussein Khursheed Aurangzeb Fa Zhu 《Computers, Materials & Continua》 2025年第4期575-593,共19页
The correction of Light Detection and Ranging(LiDAR)intensity data is of great significance for enhancing its application value.However,traditional intensity correction methods based on Terrestrial Laser Scanning(TLS)... The correction of Light Detection and Ranging(LiDAR)intensity data is of great significance for enhancing its application value.However,traditional intensity correction methods based on Terrestrial Laser Scanning(TLS)technology rely on manual site setup to collect intensity training data at different distances and incidence angles,which is noisy and limited in sample quantity,restricting the improvement of model accuracy.To overcome this limitation,this study proposes a fine-grained intensity correction modeling method based on Mobile Laser Scanning(MLS)technology.The method utilizes the continuous scanning characteristics of MLS technology to obtain dense point cloud intensity data at various distances and incidence angles.Then,a fine-grained screening strategy is employed to accurately select distance-intensity and incidence angle-intensity modeling samples.Finally,based on these samples,a high-precision intensity correction model is established through polynomial fitting functions.To verify the effectiveness of the proposed method,comparative experiments were designed,and the MLS modeling method was validated against the traditional TLS modeling method on the same test set.The results show that on Test Set 1,where the distance values vary widely(i.e.,0.1–3 m),the intensity consistency after correction using the MLS modeling method reached 7.692 times the original intensity,while the traditional TLS modeling method only increased to 4.630 times the original intensity.On Test Set 2,where the incidence angle values vary widely(i.e.,0○–80○),the MLS modeling method,although with a relatively smaller advantage,still improved the intensity consistency to 3.937 times the original intensity,slightly better than the TLS modeling method’s 3.413 times.These results demonstrate the significant advantage of the modeling method proposed in this study in enhancing the accuracy of intensity correction models. 展开更多
关键词 LIDAR intensity correction mobile laser scanning distance and incidence angle MODELING
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Toxicity variability in Alexandrium pacificum isolated from East China Sea:impact of temperature and light intensity
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作者 Xuexia ZHU Tianchi YIN +1 位作者 Min PANG Jun WANG 《Journal of Oceanology and Limnology》 2025年第1期147-158,共12页
Suitable temperature and light intensity play important roles in the formation of harmful algae blooms(HABs),which can pose serious threats to aquatic ecosystems and human health.In this study,we measured the growth,p... Suitable temperature and light intensity play important roles in the formation of harmful algae blooms(HABs),which can pose serious threats to aquatic ecosystems and human health.In this study,we measured the growth,physiological function,and paralytic shellfish toxins(PSTs)production of Alexandrium pacificum(CCMA-272),a strain isolated from East China Sea,at different temperatures(15,20,and 25℃)and light intensities(30,60,and 90μmol photons/(m^(2)·s)).Results indicate that temperature and light intensity significantly affected the growth,physiology,and toxigenic potentials of A.pacificum.The optimal conditions for the growth of A.pacificum were observed at 20℃ under60μmol photons/(m^(2)·s).Regarding the production of PSTs,this strain of A.pacificum produced 12 PSTs,including carbamate toxins:saxitoxin(STX),neosaxitoxin(NEO),and gonyautoxin 1–4(GTX1,GTX2,GTX3,GTX4);dicarbamoyl toxins:dicarbamoylsaxitoxin(dcSTX),dicarbamoylgonyautoxin 2,3(dcGTX2,dcGTX3);and N-sulfocarbamoyl toxins:N-sulfocarbamoylgonyautoxin 1,2(C1,C2),and gonyautoxin 5(GTX5).Among all the PSTs,C2 was the most abundant.Low temperature(15℃)and high light intensity(90μmol photons/(m^(2)·s))were beneficial for the production of PSTs in A.pacificum.When cultured at 20 and 25℃,A.pacificum generated comparable total quantities of PSTs,yet the toxicity levels were lower at 25℃.Intra-cellular PSTs contents were greater than extra-cellular PSTs contents,except those under the condition of 25℃ with 30μmol photons/(m^(2)·s).However,as the increase of temperature,A.pacificum released more amounts of analogues with higher toxicity levels(e.g.,STX and dcGTX_(2))into the environment than intracellularly.These findings emphasize the significant sensitivity of A.pacificum to temperature and light intensity,highlighting the importance of evaluating both intra-cellular and extra-cellular PSTs for assessing its toxicity and aiding in the prediction and management of HABs. 展开更多
关键词 TEMPERATURE light intensity Alexandrium pacificum paralytic shellfish toxin harmful algal bloom
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Energy field intensity approach for probabilistic notch fatigue assessment under size effect
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作者 Ding LIAO Shunpeng ZHU +4 位作者 Jiewei GAO Xuekang LI José CORREIA Rui CALÇADA Qingyuan WANG 《Chinese Journal of Aeronautics》 2025年第2期111-127,共17页
The development of modern engineering components and equipment features large size,intricate shape and long service life,which places greater demands on valid methods for fatigue performance analysis.Achieving a smoot... The development of modern engineering components and equipment features large size,intricate shape and long service life,which places greater demands on valid methods for fatigue performance analysis.Achieving a smooth transformation between small-scale laboratory specimens’fatigue properties and full-scale engineering components’fatigue strength has been a long-term challenge.In this work,two dominant factors impeding the smooth transformation—notch and size effect were experimentally studied,in which fatigue tests on Al 7075-T6511(a very high-strength aviation alloy)notched specimens of different scales were carried out.Fractography analyses identified the evidence of the size effect on notch fatigue damage evolution.Accordingly,the Energy Field Intensity(EFI)initially developed for multiaxial notch fatigue analysis was improved by utilizing the volume ratio of the Effective Damage Zones(EDZs)for size effect correction.In particular,it was extended to a probabilistic model considering the inherent variability of the fatigue phenomenon.The experimental data of Al 7075-T6511 notched specimens and the model-predicted results were compared,indicating the high potential of the proposed approach in fatigue evaluation under combined notch and size effects. 展开更多
关键词 Notch fatigue Size effect Energy field intensity Life prediction Probabilistic modelling
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Variations in optimal seismic intensity measures for shallowly buried bias loess tunnels
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作者 SUN Weiyu LIN Juncen +1 位作者 WANG Bo YAN Songhong 《Journal of Mountain Science》 2025年第5期1658-1673,共16页
Uneven terrain significantly increases the seismic risk of tunnels in loess deposits.To investigate the variations in optimal intensity measures(IMs)for shallowly buried loess tunnels considering biased terrain,nonlin... Uneven terrain significantly increases the seismic risk of tunnels in loess deposits.To investigate the variations in optimal intensity measures(IMs)for shallowly buried loess tunnels considering biased terrain,nonlinear dynamic analyses were conducted to obtain seismic responses validated by the actual damage pattern.Then IMs were evaluated based on the automatic calculation of the time history damage index fulfilled by a compiled Python program.Results showed that the plastic strain zone progressively developed and extended from the vault to the central slope surface with increasing seismic intensities,ultimately causing shear failure to the tunnel.For IMs at the slope top,peak ground velocity(PGV)(ζ=0.15),velocity spectrum intensity(VSI)(ζ=0.20),and peak spectrum velocity(PSv)(ζ=0.22)were all suitable for seismic fragility assessment.The VSI(ζ=0.17)was optimal,followed by PGV(ζ=0.19)and PSv(ζ=0.2)for those at the slope foot.Acceleration-related IMs were more sensitive to terrain variation.Comparative analyses demonstrated smaller damage probabilities for the IMs at the slope top than those at the slope foot under the same intensity level.The impact of unfavorable terrain on tunnels was accentuated as those located in uneven mountainous regions became more vulnerable to ground shaking. 展开更多
关键词 Shallowly buried bias Loess tunnels Slope failure Seismic intensity measures Fragility assessment
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Hepatic enhancement and signal intensity analysis on magnetic resonance imaging as prognostic biomarkers in advanced chronic liver disease
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作者 Bogdan-Ioan Stanciu Marcela Iojiban +4 位作者 Andreea Morariu-Barb Cosmin Caraiani Bogdan Procopet Horia Stefanescu Monica Lupsor-Platon 《World Journal of Hepatology》 2025年第12期97-122,共26页
BACKGROUND Advanced chronic liver disease is a progressive condition associated with high mor-bidity and mortality,leading to complications such as decompensation and hepatocellular carcinoma.Although prognostic score... BACKGROUND Advanced chronic liver disease is a progressive condition associated with high mor-bidity and mortality,leading to complications such as decompensation and hepatocellular carcinoma.Although prognostic scores such as the Child-Pugh score(which combines clinical assessment and laboratory parameters)and laboratory-based models,including Model for End-Stage Liver Disease(MELD)3.0,albumin-bilirubin(ALBI)grade,and fibrosis-4(FIB-4),are often used,their accuracy is limited by subjective assessments and variability in laboratory results.The Functional Liver Imaging Score(FLIS),a semi-quantitative magnetic resonance imaging(MRI)measure of liver function,may also be influenced by observer variability.This emphasizes the need for objective,reproducible tools to improve risk stratification and support treatment decision-making.AIM To evaluate the prognostic value of hepatic enhancement(HE)and signal intensity measured by gadoxetate disodium-enhanced MRI.METHODS In this retrospective cohort study,100 patients with advanced chronic liver disease underwent gadoxetateenhanced MRI.HE and signal intensity were measured quantitatively in liver segments III,VI,VIII,and the caudate lobe,and global values were calculated by averaging segmental measurements.Correlations were assessed with FLIS,Child-Pugh,MELD 3.0,ALBI,FIB-4,liver stiffness(FibroScan),and hepatic venous pressure gradient.Cox regression and receiver operating characteristic analysis were used to evaluate associations with hepatic decompensation,mortality,and hepatocellular carcinoma(HCC)occurrence during follow-up.RESULTS Global HE showed a significant correlation with FLIS(r=0.797),Child-Pugh(r=-0.589),MELD 3.0(r=-0.658),ALBI(r=-0.599),FIB-4(r=-0.308),liver stiffness(r=-0.470),and hepatic venous pressure gradient(r=-0.340).Lower HE was significantly associated with a higher risk of decompensation and mortality in univariate Cox regression.After adjustment for MELD 3.0,etiology,and prior HCC,segment VI HE remained independently predictive of mortality.At 12 months,HE improved risk stratification for mortality and reduced unnecessary interventions by 11 per 100 patients at a 10%threshold in the decision curve analysis.HE had an area under the receiver operating characteristic curve of 0.74 for predicting decompensation and 0.74 for predicting mortality.HE was higher in patients who developed or experienced recurrence of HCC during follow-up,but this was not statistically significant(P=0.1).CONCLUSION Lower HE in segment VI improved prognostic classification of high-risk patients.These patients align with Baveno VII criteria for intensified management,supporting the potential role of HE in risk-adapted surveillance. 展开更多
关键词 Advanced chronic liver disease Magnetic resonance imaging Gadoxetate disodium Hepatic enhancement Signal intensity Prognostic biomarkers Liver function assessment
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Spatial and temporal pattern of human activity intensity and its driving mechanism in the Turpan-Hami Basin,China from 1990 to 2020
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作者 SHI Qingqing YIN Benfeng +3 位作者 HUANG Jixia YIN Yuanyuan YANG Ao ZHANG Yuanming 《Journal of Arid Land》 2025年第11期1497-1517,共21页
The Turpan-Hami(Tuha)Basin of China,a critical region on the Silk Road Economic Belt and a major national energy base,occupies a significant position in energy security and in the major industrial clusters in Xinjiang... The Turpan-Hami(Tuha)Basin of China,a critical region on the Silk Road Economic Belt and a major national energy base,occupies a significant position in energy security and in the major industrial clusters in Xinjiang Uygur Autonomous Region,China.Understanding spatial and temporal evolution of human activities in this area is essential for harmonizing ecological protection with energy development,safeguarding the ecological security of the Silk Road Economic Belt,and promoting the sustainable development of the area.However,despite rapid socioeconomic advances,the trajectories of human activity intensity and the principal driving mechanisms over the past three decades remain inadequately understood.To address these gaps,this study constructed a land use dataset for the Tuha Basin from 1990 to 2020,utilizing Google Earth Engine(GEE)and random forest classification algorithm.We assessed the intensity of human activities and their spatial autocorrelation patterns and further identified key drivers influencing spatial and temporal variations using the Geodetector model.Our findings indicated that the intensity of human activities in the Tuha Basin has exhibited a"first decline and then recovery"trend over the past 30 a,accompanied by significant spatial clustering.In recent years,the aggregation of hot spots has diminished,while clustering of cold spots has intensified,suggesting a dispersion of human activity centers.Nevertheless,urban areas in the Hami and Turpan cities,along with their surrounding areas,continued to serve as core areas of human activities.Topographic features(slope gradient and aspect)and their interactions with economic variables emerged as dominant determinants shaping the spatial patterns and temporal dynamics of human activity intensity.This result provides critical insights into fostering sustainable regional development and ecological conservation in the Tuha Basin and offers valuable methodological and empirical references for studies on land use dynamics and human activity intensity in similar arid areas. 展开更多
关键词 Turpan-Hami Basin land use change Google Earth Engine human activity intensity INTERACTION
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Empirical correlation between the elastic input energy and typical intensity measures for offshore ground motions
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作者 Hu Jinjun Tian Hao +2 位作者 Tan Jingyang Liu Mingji Jin Chaoyue 《Earthquake Engineering and Engineering Vibration》 2025年第3期653-674,I0002-I0012,共33页
To analyze the correlation between the input energy parameters(V_(E))and typical intensity measures(IMs)of offshore ground motions,based on 273 earthquake events recorded by the K-NET in Japan,892 offshore ground moti... To analyze the correlation between the input energy parameters(V_(E))and typical intensity measures(IMs)of offshore ground motions,based on 273 earthquake events recorded by the K-NET in Japan,892 offshore ground motion records with moment magnitudes from 4.0 to 7.0 were used in this study.Residuals obtained through a ground motion model were calculated and analyzed for the correlation between V_(E) and amplitude,duration,frequency content and cumulative IMs.The results indicate that PGV and PGD have strong correlation with the V_(E)(T>0.2 s and T>0.4 s),the duration IMs have weakly negative correlation with the V_(E),Sd_(1) has a strong correlation with the V_(E) in the periods of T>0.4 s,T_(g) has a weak correlation with V_(E) and the cumulative IMs have strong correlation with the V_(E).The parametric predictive equations between typical IMs and V_(E) was proposed,and the differences between the prediction equations from the onshore ground motion records were compared.The differences in parametric predicted equations between offshore and onshore ground motions were confirmed in this study.Proposed correlation equations can be applied to offshore probabilistic seismic hazard analysis and the selection of ground motion records by generalized conditional intensity measures. 展开更多
关键词 input energy offshore ground motion intensity measures empirical correlation parametric prediction equations
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