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CLINICAL REPORT ON MULTI-CENTER RANDOMIZED CONTROLLED TRIAL OF TREATMENT OF MIGRAINE BY ELECTRO-ACUPUNCTURE AT QI■X■(丘墟GB40) 被引量:1
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作者 贾春生 马小顺 +10 位作者 石晶 王耀民 李永方 袁军 李梅 郑利星 张祥建 王少锦 高建英 李晓峰 霍永利 《World Journal of Acupuncture-Moxibustion》 2008年第1期1-9,共9页
Objective To observe the therapeutic effect of electro acupuncture at QIǖXǖ(丘墟GB40) for treating migraine and provide clinical study for Acupoints Dictionary of People's Republic of China. Methods Multi-center ... Objective To observe the therapeutic effect of electro acupuncture at QIǖXǖ(丘墟GB40) for treating migraine and provide clinical study for Acupoints Dictionary of People's Republic of China. Methods Multi-center (3 First-Class hospitals) study was adopted, and the involved 3 hospitals did clinical observation according to the requirements of the project. The methods are as follows. All cases were randomized into treatment group and control group according to their sequence. QIǖXǖ(丘墟GB40) was selected in treatment group, while Tiānshū (天枢 ST25) was selected in control group. Both groups were performed electro acupuncture, and syndromes indexes of migraine and 5-HT were observed before and after treatment. All data were analyzed by statistic software SPSS11.5. Results There was significant difference of VAS margin between two groups in each center and the combined center (u= -3. 362, P=0. 001 ). There was significant difference of therapeutic effect of 4-week treatment between two groups in each clinical center and the combined center. The therapeutic effect of 3-month treatment between two groups in No. 1 and No. 3 hospitals, showed significant difference, the treatment group was better; while that of No. 2 hospital had no obvious difference. The therapeutic effect of 6-month treatment between two groups in each center and the combined center had significant difference, the treatment group was better. Conclusion The therapy of electro acupuncture at QIǖXǖ(丘墟GB40) is effective for migraine. 展开更多
关键词 QIǖXǖ(丘墟GB40) Electro acupuncture Migraine multi-center clinical observation
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Probing the structure of multi-center molecules with odd–even high harmonics 被引量:4
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作者 Ning Su Shujuan Yu +2 位作者 Weiyan Li Shiping Yang Yanjun Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期274-280,共7页
We study high-order harmonic generation(HHG)from multi-center asymmetric linear molecules numerically and analytically.Our simulations show that odd and even HHG spectra of the asymmetric multi-center system respond d... We study high-order harmonic generation(HHG)from multi-center asymmetric linear molecules numerically and analytically.Our simulations show that odd and even HHG spectra of the asymmetric multi-center system respond differently to the change of the molecular structure.Specifically,when the internuclear distances between these nuclei of the molecule have a small change,the odd spectra usually do not change basically,but the even spectra differ remarkably.Based on this phenomenon,a simple procedure is proposed to probe the positions of these nuclei with odd–even HHG.Our results shed light on attosecond probing of the structure of multi-center molecules using HHG. 展开更多
关键词 odd-even harmonics multi-center asymmetric molecules molecular structure
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Effect of a disposable endoscope precleaning kit in the cleaning procedure of gastrointestinal endoscope:A multi-center observational study 被引量:1
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作者 Yi-Fan Wang Yu Wu +10 位作者 Xiao-Wei Liu Jian-Guo Li Yan-Qiong Zhan Bin Liu Wen-Ling Fan Zi-Heng Peng Jin-Tao Xiao Bing-Bing Li Jian He Jun Yi Zhao-Xia Lu 《World Journal of Gastrointestinal Endoscopy》 2023年第12期705-714,共10页
BACKGROUND Precleaning is a key step in endoscopic reprocessing.AIM To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.METHODS Altogether,228 used ga... BACKGROUND Precleaning is a key step in endoscopic reprocessing.AIM To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.METHODS Altogether,228 used gastrointestinal endoscopes were selected from five high-volume endoscopy units and precleaned by a traditional precleaning bucket(group T)or a disposable endoscope bedside precleaning kit(group D).Each group was further subdivided based on the replacement frequency of the cleaning solution,which was replaced every time in subgroups T1 and D1 and every several times in subgroups Ts and Ds.The adenosine triphosphate(ATP)level and residual proteins were measured three times:Before and after precleaning and after manual cleaning.RESULTS After precleaning,the precleaning kit significantly reduced the ATP levels(P=0.034)and has a more stable ATP clearance rate than the traditional precleaning bucket.The precleaning kit also saved a quarter of the cost of enzymatic detergent used during the precleaning process.After manual cleaning,the ATP levels were also significantly lower in the precleaning kit group than in the traditional precleaning bucket group(P<0.05).Meanwhile,the number of uses of the cleaning solution(up to four times)has no significant impact on the cleaning effect(P>0.05).CONCLUSION Considering its economic cost and cleaning effect,the use of a disposable endoscope bedside precleaning kit can be an optimal option in the precleaning stage with the cleaning solution being replaced several times in the manual cleaning stage. 展开更多
关键词 Cleaning effect Economic cost ENDOSCOPE multi-center study Precleaning
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Minimum MSE Weights of Adjusted Summary Estimator of Risk Difference in Multi-Center Studies 被引量:1
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作者 Chukiat Viwatwongkasem Jirawan Jitthavech +1 位作者 Dankmar Bohning Vichit Lorchirachoonkul 《Open Journal of Statistics》 2012年第1期48-59,共12页
The simple adjusted estimator of risk difference in each center is easy constructed by adding a value c on the number of successes and on the number of failures in each arm of the proportion estimator. Assessing a tre... The simple adjusted estimator of risk difference in each center is easy constructed by adding a value c on the number of successes and on the number of failures in each arm of the proportion estimator. Assessing a treatment effect in multi-center studies, we propose minimum MSE (mean square error) weights of an adjusted summary estimate of risk difference under the assumption of a constant of common risk difference over all centers. To evaluate the performance of the proposed weights, we compare not only in terms of estimation based on bias, variance, and MSE with two other conventional weights, such as the Cochran-Mantel-Haenszel weights and the inverse variance (weighted least square) weights, but also we compare the potential tests based on the type I error probability and the power of test in a variety of situations. The results illustrate that the proposed weights in terms of point estimation and hypothesis testing perform well and should be recommended to use as an alternative choice. Finally, two applications are illustrated for the practical use. 展开更多
关键词 Minimum MSE WEIGHTS Optimal WEIGHTS Cochran-Mantel-Haenszel WEIGHTS Inverse Variance WEIGHTS multi-center STUDIES Risk Difference
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Analysis of gravity wave activity during stratospheric sudden warmings in the northern hemisphere 被引量:2
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作者 XuanYun Zeng Guang Zhong 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期415-422,共8页
Due to the significant changes they bring to high latitude stratospheric temperature and wind,stratospheric sudden warmings(SSWs)can have an impact on the propagation and energy distribution of gravity waves(GWs).The ... Due to the significant changes they bring to high latitude stratospheric temperature and wind,stratospheric sudden warmings(SSWs)can have an impact on the propagation and energy distribution of gravity waves(GWs).The variation characteristics of GWs during SSWs have always been an important issue.Using temperature data from January to March in 2014−2016,provided by the Constellation Observing System for Meteorology,Ionosphere and Climate(COSMIC)mission,we have analyzed global GW activity at 15−40 km in the Northern Hemisphere during SSW events.During the SSWs that we studied,the stratospheric temperature rose in one or two longitudinal regions in the Northern Hemisphere;the areas affected extended to the east of 90°W.During these SSWs,the potential energy density(E_(p)of GWs expanded and covered a larger range of longitude and altitude,exhibiting an eastward and downward extension.The E_(p)usually increased,while partially filtered by the eastward zonal winds.When zonal winds weakened or turned westward,E_(p)began to strengthen.After SSWs,the E_(p)usually decreased.These observations can serve as a reference for analyzing the interaction mechanism between SSWs and GWs in future work. 展开更多
关键词 stratospheric sudden warming gravity wave wind filter
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Theoretical study of(e,2e) triple differential cross section of 1b3g orbital of ethylene by vibrational multi-center distorted-wave method
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作者 王振鹏 宫毛毛 +2 位作者 李星宇 张松斌 陈向军 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期306-312,共7页
The vibrational motions are usually neglected when calculating(e,2e) triple differential cross sections(TDCSs) of molecules. Here, multi-center distorted-wave method(MCDW) has been modified by including molecular vibr... The vibrational motions are usually neglected when calculating(e,2e) triple differential cross sections(TDCSs) of molecules. Here, multi-center distorted-wave method(MCDW) has been modified by including molecular vibrations. This vibrational MCDW method is employed to calculate the TDCSs of 1b3gorbital of ethylene at low(100 eV) and medium(250 eV) incident electron energies in coplanar asymmetric kinematic condition. The results show that molecular vibrations significantly influence the angular distributions of the TDCSs, especially in the binary region along momentum transfer near the Bethe ridge. 展开更多
关键词 (e 2e) multi-center distorted-wave method(MCDW) vibrational effect
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Theoretical study of (e,2e) triple differential cross sections of pyrimidine and tetrahydrofurfuryl alcohol molecules using multi-center distorted-wave method
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作者 Yiao Wang Zhenpeng Wang +2 位作者 Maomao Gong Chunkai Xu Xiangjun Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期118-123,共6页
We report theoretical studies of electron impact triple differential cross sections of two bio-molecules,pyrimidine and tetrahydrofurfuryl alcohol,in the coplanar asymmetric kinematic conditions with the impact energy... We report theoretical studies of electron impact triple differential cross sections of two bio-molecules,pyrimidine and tetrahydrofurfuryl alcohol,in the coplanar asymmetric kinematic conditions with the impact energy of 250 eV and ejected electron energy of 20 eV at three scattering angles of-5°,-10°,and-15°.Present multi-center distorted-wave method well describes the experimental data,which was obtained by performing(e,2e)experiment.The calculations show that the secondary electron produced by the primary impact electron is strongly influenced by the molecular ionic multi-center potential,which must be considered when the low energy electron interacts with DNA analogues. 展开更多
关键词 (E 2E) bio-molecules multi-center distorted-wave method(MCDW)
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Multi-Order and Multi-Center Metallogenic Zoning of Yinshan Cu-Au Polymetallic Ore Deposit,Jiangxi Province,China
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作者 Mo Cehui Liu Danying Feng Zhiwen Xia WeflwaChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1993年第1期70-73,共4页
Yinshan anticline is the product of tectono-dynamic deformation - metamorphism .Along the axis of the anticline exists a brittle-ductile shearing zone which obviously controls the ore-formation . Mineralization occurs... Yinshan anticline is the product of tectono-dynamic deformation - metamorphism .Along the axis of the anticline exists a brittle-ductile shearing zone which obviously controls the ore-formation . Mineralization occurs along the axis of the anticline in a width of about 1000m .In the mining area .volcano- subvolcanic rocks of Early Yanshan period are divided into three cycles :Ⅰ intermediate acidic dacite lava and dacite porphyry ;Ⅱ acidic amphibole liparite and quartz porphyry;Ⅲ intermediate andesite porphyrite . Among them activities of ⅠandⅡ cycles are more intensive and are intimately related to the mineralization . Yinshan ore deposit is the result of combinative processes of tectono -dynamic and volcano -magmatic hydrothermal fluids, so that mere are two centers of metallogenic zoning, one being the axial strain zone of Yinshan anticline which is the center of first order, and the other being porphyry stock , 2nd order. 展开更多
关键词 Yinshan polymetallic deposit multi-order and multi-center metallogenic zoning brittle-ductile shearing zone porphyry stock .
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The Volume Effect and Safety of 6% Hydroxyethyl Starch 130/0.4 in Patients Undergoing Major Elective Surgery: An Uncontrolled, Open-Labeled, Multi-Center Study
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作者 Nobutada Morioka Makoto Ozaki +6 位作者 Michiaki Yamakage Hiroshi Morimatsu Yasuyuki Suzuki Frank Bepperling Hideki Miyao Akiyoshi Namiki Kiyoshi Morita 《Open Journal of Anesthesiology》 2013年第7期326-337,共12页
Purpose: The primary aim of this study was to investigate volume effect and safety of up to 50 mL/kg BW 6% hydroxyethyl starch (HES) 130/0.4 in adult and pediatric patients undergoing major elective surgery. The need ... Purpose: The primary aim of this study was to investigate volume effect and safety of up to 50 mL/kg BW 6% hydroxyethyl starch (HES) 130/0.4 in adult and pediatric patients undergoing major elective surgery. The need to infuse human albumin may be reduced or avoided in Japan if these large doses 6% HES 130/0.4 can be infused. Methods: The study was an uncontrolled, open-labeled, multi-center trial. Fifteen adult and 5 pediatric patients undergoing major elective surgery received 6% HES 130/0.4 (Voluven&#174) with a maximum dose of 50 mL/kg from the start of surgery until 2 hours after the end of surgery according to a treatment algorithm. The primary efficacy endpoint was the volume effect of 6% HES 130/0.4 determined by the volume of saved albumin during the investigational period and the time course of hemodynamic stability in adult and pediatric patients. Safety parameters were fluid balance, hemodynamic and laboratory parameters ECG, local and systemic tolerance and adverse events. Results: Adult patients received a mean of 32.0 mL/kg of 6% HES 130/0.4. For 12 out of 15 adult patients an average amount of 1033.8 mL (18.6 mL/kg) albumin could be saved. The other 3 adult patients did not receive more than 1000 mL of HES 130/0.4. All pediatric patients received approximately 50 mL/kg of HES 130/0.4;for these patients an average amount of 39.9 mL/kg body weight albumin could be saved. The majority of adult patients, and all pediatric patients were hemodynamically stable at all 3 time points. The observed changes of the assessed laboratory parameters including hematological and coagulation parameters or in any other safety parameter determined did not reveal any safety concern related to the administration of 6% HES 130/0.4 up to doses of 50 mL/kg body weight. Conclusion: The study results indicate that 6% HES 130/0.4 has a reliable volume effect, could contribute to significant human albumin savings and was safe and well tolerated up to a maximum dose of 50 mL/kg body weight in adult and pediatric patients undergoing major elective surgery. 展开更多
关键词 High DOSE Volume Effect SAFETY 6% Hydroxyethyl STARCH 130/0.4 ELECTIVE Surgery multi-center Study
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Characteristics and control factors of feldspar dissolution in gravity flow sandstone of Chang 7 Member,Triassic Yanchang Formation,Ordos Basin,NW China 被引量:1
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作者 ZHU Haihua ZHANG Qiuxia +4 位作者 DONG Guodong SHANG Fei ZHANG Fuyuan ZHAO Xiaoming ZHANG Xi 《Petroleum Exploration and Development》 SCIE 2024年第1期114-126,共13页
To clarify the formation and distribution of feldspar dissolution pores and predict the distribution of high-quality reservoir in gravity flow sandstone of the 7^(th) member of Triassic Yanchang Formation(Chang 7 Memb... To clarify the formation and distribution of feldspar dissolution pores and predict the distribution of high-quality reservoir in gravity flow sandstone of the 7^(th) member of Triassic Yanchang Formation(Chang 7 Member)in the Ordos Basin,thin sections,scanning electron microscopy,energy spectrum analysis,X-ray diffraction whole rock analysis,and dissolution experiments are employed in this study to investigate the characteristics and control factors of feldspar dissolution pores.The results show that:(1)Three types of diagenetic processes are observed in the feldspar of Chang 7 sandstone in the study area:secondary overgrowth of feldspar,replacement by clay and calcite,and dissolution of detrital feldspar.(2)The feldspar dissolution of Chang 7 tight sandstone is caused by organic acid,and is further affected by the type of feldspar,the degree of early feldspar alteration,and the buffering effect of mica debris on organic acid.(3)Feldspars have varying degrees of dissolution.Potassium feldspar is more susceptible to dissolution than plagioclase.Among potassium feldspar,orthoclase is more soluble than microcline,and unaltered feldspar is more soluble than early kaolinized or sericitized feldspar.(4)The dissolution experiment demonstrated that the presence of mica can hinder the dissolution of feldspar.Mica of the same mass has a significantly stronger capacity to consume organic acids than feldspar.(5)Dissolution pores in feldspar of Chang 7 Member are more abundant in areas with low mica content,and they improve the reservoir physical properties,while in areas with high mica content,the number of feldspar dissolution pores decreases significantly. 展开更多
关键词 gravity flow sandstone differential feldspar dissolution mica-feldspar dissolution experiment Chang 7 Member of Triassic Yanchang Formation Ordos Basin
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Influence of topography on the fine structures of stratospheric gravity waves:An analysis using COSMIC-2 temperature data 被引量:1
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作者 JiaRui Wei Xiao Liu +2 位作者 JiYao Xu QinZeng Li Hong Gao 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期497-513,共17页
We derive the potential energy of gravity waves(GWs)in the upper troposphere and stratosphere at 45°S-45°N from December 2019 to November 2022 by using temperature profiles retrieved from the Constellation O... We derive the potential energy of gravity waves(GWs)in the upper troposphere and stratosphere at 45°S-45°N from December 2019 to November 2022 by using temperature profiles retrieved from the Constellation Observing System for Meteorology,Ionosphere,and Climate-2(COSMIC-2)satellite.Owing to the dense sampling of COSMIC-2,in addition to the strong peaks of gravity wave potential energy(GWPE)above the Andes and Tibetan Plateau,we found weak peaks above the Rocky,Atlas,Caucasus,and Tianshan Mountains.The land-sea contrast is responsible for the longitudinal variations of the GWPE in the lower and upper stratosphere.At 40°N/S,the peaks were mainly above the topographic regions during the winter.At 20°N/S,the peaks were a slight distance away from the topographic regions and might be the combined effect of nontopographic GWs and mountain waves.Near the Equator,the peaks were mainly above the regions with the lowest sea level altitude and may have resulted from convection.Our results indicate that even above the local regions with lower sea level altitudes compared with the Andes and Tibetan Plateau,the GWPE also exhibits fine structures in geographic distributions.We found that dissipation layers above the tropopause jet provide the body force to generate secondary waves in the upper stratosphere,especially during the winter months of each hemisphere and at latitudes of greater than 20°N/S. 展开更多
关键词 TOPOGRAPHY fine structures stratospheric gravity waves Constellation Observing System for Meteorology Ionosphere and Climate-2(COSMIC-2) dissipation layers
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Probing signals of atmospheric gravity waves excited by the July 29,2021 M_(W)8.2 Alaska earthquake
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作者 Geng Zhang Jianqiao Xu +2 位作者 Xiaodong Chen Heping Sun Lizhuo Gong 《Geodesy and Geodynamics》 EI CSCD 2024年第3期219-229,共11页
It is commonly believed that the atmosphere is decoupled from the solid Earth.Thus,it is difficult for the seismic wave energy inside the Earth to propagate into the atmosphere,and atmospheric pressure wave signals ex... It is commonly believed that the atmosphere is decoupled from the solid Earth.Thus,it is difficult for the seismic wave energy inside the Earth to propagate into the atmosphere,and atmospheric pressure wave signals excited by earthquakes are unlikely to exist in atmospheric observations.An increasing number of studies have shown that earthquakes,volcanoes,and tsunamis can perturb the Earth's atmosphere due to various coupling effects.However,the observations mainly focus on acoustic waves with periods of less than 10 min and inertial gravity waves with periods of greater than 1 h.There are almost no clear observations of gravity waves that coincide with observations of low-frequency signals of the Earth's free oscillation frequency band within 1 h.This paper investigates atmospheric gravity wave signals within1 h of surface-atmosphere observations using the periodogram method based on seismometer and microbarometer observations from the global seismic network before and after the July 29,2021 M_(w)8.2 Alaska earthquake in the United States.The numerical results show that the atmospheric gravity wave signals with frequencies similar to those of the Earth's free oscillations _(0)S_(2) and _(0)T_(2) can be detected in the microbaro meter observations.The results con firm the existence of atmospheric gravity waves,indicating that the atmosphere and the solid Earth are not decoupled within this frequency band and that seismic wave energy excited by earthquakes can propagate from the interior of the Earth to the atmosphere and enhance the atmospheric gravity wave signals within 1 h. 展开更多
关键词 Atmospheric gravity modes Atmospheric gravity waves Alaska earthquake Normal modes Coupling of solid earth and atmosphere
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Quintessence anisotropic stellar models in quadratic and Born-Infeld modified teleparallel Rastall gravity
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作者 Allah Ditta 夏铁成 +1 位作者 Irfan Mahmood Asif Mahmood 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期179-189,共11页
This study aims to discuss anisotropic solutions that are spherically symmetric in the quintessence field,which describe compact stellar objects in the modified Rastall teleparallel theory of gravity.To achieve this g... This study aims to discuss anisotropic solutions that are spherically symmetric in the quintessence field,which describe compact stellar objects in the modified Rastall teleparallel theory of gravity.To achieve this goal,the Krori and Barua arrangement for spherically symmetric components of the line element is incorporated.We explore the field equations by selecting appropriate off-diagonal tetrad fields.Born-Infeld function of torsion f(T)=β√λT+1-1 and power law form h(T)=δTn are used.The Born-Infeld gravity was the first modified teleparallel gravity to discuss inflation.We use the linear equation of state pr=ξρto separate the quintessence density.After obtaining the field equations,we investigate different physical parameters that demonstrate the stability and physical acceptability of the stellar models.We use observational data,such as the mass and radius of the compact star candidates PSRJ 1416-2230,Cen X-3,&4U 1820-30,to ensure the physical plausibility of our findings. 展开更多
关键词 anisotropic spheres quintessence field modified Rastall teleparallel gravity equation of state(EoS) f(T)gravity
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Gravity Fault Subsidence and Beach Ridges Progradation in Quinta-Cassino (RS) Coastal Plain, Brazil
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作者 Bruno Silva da Fontoura Adelir José Strieder +3 位作者 Iran Carlos Stalliviere Corrêa Paulo Rogério Mendes Alexandre Felipe Bruch Angélica Cirolini 《Open Journal of Geology》 CAS 2024年第2期177-195,共19页
Ground penetrating radar (GPR) surveys have being applied to investigate very near-surface stratification of sedimentary units in coastal plains and to define their depositional conditions. This paper presents, howeve... Ground penetrating radar (GPR) surveys have being applied to investigate very near-surface stratification of sedimentary units in coastal plains and to define their depositional conditions. This paper presents, however, low-frequency GPR survey to investigate fault-related depositional systems at greater depths. The Quinta-Cassino area in the Rio Grande do Sul Coastal Plain (RGSCP, Brazil) shows a wide strandplain that is made off by very long, continuous, and linear geomorphic features (beach ridges). This strandplain extends for ~70 km southward. The beach ridges show low-angle truncations against the Quinta escarpment, and also truncations in the strandplain. The traditional approach points that RGSCP was developed by juxtaposition of four lagoons/barrier systems as consequence of sea level changes;previous model assumes that no deformational episode occurred in RGSCP. The geophysical and geological surveys carried out in this area showed the existence of listric fault controlling the beach ridges in the escarpments and hanging-wall blocks. The radargrams could distinguish Pleistocene basement unit anticlockwise rotation, thickening of beach ridges radarfacies close to listric normal faults, and horst structures. These deformational features indicate that the extensional zone of a large-scale gravity-driven structure controlled the mechanical subsidence, the Holocene sedimentation and its stratigraphic and geomorphic features in the Quinta-Cassino area to build up an asymmetric delta. The results point to a new approach in dealing with RGSCP Holocene evolution. 展开更多
关键词 gravity Tectonics Normal Faults Ground Penetrating Radar Survey Beach-Ridges Progradation
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A VGGNet-based correction for satellite altimetry-derived gravity anomalies to improve the accuracy of bathymetry to depths of 6500 m
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作者 Xiaolun Chen Xiaowen Luo +6 位作者 Ziyin Wu Xiaoming Qin Jihong Shang Huajun Xu Bin Li Mingwei Wang Hongyang Wan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期112-122,共11页
Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the... Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the seafloor has been precisely modeled to date,and there is an urgent need to improve the accuracy and reduce the uncertainty of underwater survey data.In this study,we introduce a pretrained visual geometry group network(VGGNet)method based on deep learning.To apply this method,we input gravity anomaly data derived from ship measurements and satellite altimetry into the model and correct the latter,which has a larger spatial coverage,based on the former,which is considered the true value and is more accurate.After obtaining the corrected high-precision gravity model,it is inverted to the corresponding bathymetric model by applying the gravity-depth correlation.We choose four data pairs collected from different environments,i.e.,the Southern Ocean,Pacific Ocean,Atlantic Ocean and Caribbean Sea,to evaluate the topographic correction results of the model.The experiments show that the coefficient of determination(R~2)reaches 0.834 among the results of the four experimental groups,signifying a high correlation.The standard deviation and normalized root mean square error are also evaluated,and the accuracy of their performance improved by up to 24.2%compared with similar research done in recent years.The evaluation of the R^(2) values at different water depths shows that our model can achieve performance results above 0.90 at certain water depths and can also significantly improve results from mid-water depths when compared to previous research.Finally,the bathymetry corrected by our model is able to show an accuracy improvement level of more than 21%within 1%of the total water depths,which is sufficient to prove that the VGGNet-based method has the ability to perform a gravity-bathymetry correction and achieve outstanding results. 展开更多
关键词 gravity anomaly bathymetry inversion VGGNet multibeam sonar satellite altimetry
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The Structure of Gravity Funnels and Stability Considerations of Matter in SI Units
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作者 Tobias Bartusch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期71-81,共11页
This article describes an extension of the theory of vortices to electromagnetic types with a start point from known fluid systems. From this, properties of gravity-generating objects (particles and black holes) can b... This article describes an extension of the theory of vortices to electromagnetic types with a start point from known fluid systems. From this, properties of gravity-generating objects (particles and black holes) can be derived, which can also describe their possible interior. This also leads to questions about stability, which are then addressed and ultimately lead to considerations of black holes and their possible internal structure. The results fit into the observable areas and can also be directly verified because they were analytically calculated in SI units. 展开更多
关键词 Black Hole Dark Matter Electromagnetic gravity SINGULARITY VORTEX
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A method for extracting the preseismic gravity anomalies over the Tibetan Plateau based on the maximum shear strain using GRACE data
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作者 Hui Wang DongMei Song +1 位作者 XinJian Shan Bin Wang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第4期589-608,共20页
The occurrence of earthquakes is closely related to the crustal geotectonic movement and the migration of mass,which consequently cause changes in gravity.The Gravity Recovery And Climate Experiment(GRACE)satellite da... The occurrence of earthquakes is closely related to the crustal geotectonic movement and the migration of mass,which consequently cause changes in gravity.The Gravity Recovery And Climate Experiment(GRACE)satellite data can be used to detect gravity changes associated with large earthquakes.However,previous GRACE satellite-based seismic gravity-change studies have focused more on coseismic gravity changes than on preseismic gravity changes.Moreover,the noise of the north–south stripe in GRACE data is difficult to eliminate,thereby resulting in the loss of some gravity information related to tectonic activities.To explore the preseismic gravity anomalies in a more refined way,we first propose a method of characterizing gravity variation based on the maximum shear strain of gravity,inspired by the concept of crustal strain.The offset index method is then adopted to describe the gravity anomalies,and the spatial and temporal characteristics of gravity anomalies before earthquakes are analyzed at the scales of the fault zone and plate,respectively.In this work,experiments are carried out on the Tibetan Plateau and its surrounding areas,and the following findings are obtained:First,from the observation scale of the fault zone,we detect the occurrence of large-area gravity anomalies near the epicenter,oftentimes about half a year before an earthquake,and these anomalies were distributed along the fault zone.Second,from the observation scale of the plate,we find that when an earthquake occurred on the Tibetan Plateau,a large number of gravity anomalies also occurred at the boundary of the Tibetan Plateau and the Indian Plate.Moreover,the aforementioned experiments confirm that the proposed method can successfully capture the preseismic gravity anomalies of large earthquakes with a magnitude of less than 8,which suggests a new idea for the application of gravity satellite data to earthquake research. 展开更多
关键词 gravity Recovery And Climate Experiment(GRACE)data maximum shear strain offset index K preseismic gravity anomalies Tibetan Plateau fault zone
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Predicting bathymetry based on vertical gravity gradient anomaly and analyses for various influential factors
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作者 Huan Xu Jinhai Yu +3 位作者 Yanyan Zeng Qiuyu Wang Yuwei Tian Zhongmiao Sun 《Geodesy and Geodynamics》 EI CSCD 2024年第4期386-396,共11页
The prediction of bathymetry has advanced significantly with the development of satellite altimetry.However,the majority of its data originate from marine gravity anomaly.In this study,based on the expression of verti... The prediction of bathymetry has advanced significantly with the development of satellite altimetry.However,the majority of its data originate from marine gravity anomaly.In this study,based on the expression of vertical gravity gradient(VGG)of a rectangular prism,the governing equations for determining sea depths to invert bathymetry.The governing equation is solved by linearization through an iterative process,and numerical simulations verify its algorithm and its stability.We also study the processing methods of different interference errors.The regularization method improves the stability of the inversion process for errors.A piecewise bilinear interpolation function roughly replaces the low-frequency error,and numerical simulations show that the accuracy can be improved by 41.2%after this treatment.For variable ocean crust density,simulation simulations verify that the root-mean-square(RMS)error of prediction is approximately 5 m for the sea depth of 6 km if density is chosen as the average one.Finally,two test regions in the South China Sea are predicted and compared with ship soundings data,RMS errors of predictions are 71.1 m and 91.4 m,respectively. 展开更多
关键词 Rectangular prism Vertical gravity gradient BATHYMETRY Numerical simulation Prediction error
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Gravity and the Nature of Physical Interactions
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作者 Kajetan Młynarski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1578-1612,共35页
This work is a kind of thought experiment aimed at answering the question: what might a theory look like in which time and space (spacetime) are not fundamental? The article formulates theoretical frameworks that intr... This work is a kind of thought experiment aimed at answering the question: what might a theory look like in which time and space (spacetime) are not fundamental? The article formulates theoretical frameworks that introduce the number of spacetime dimensions, the principle of equivalence of mass, and the value of the gravitational constant not as empirically given data, but as results of theoretical deduction. This analysis opens up potential connections between gravitational and electrostatic interactions, proposing a new approach to traditional physical assumptions. The theory is presented in a preliminary form, intended to inspire possible further research. The final part of the paper proposes experiments to verify these ideas. 展开更多
关键词 Time SPACE gravity Principle of Equivalence Gravitational Constant Planck Mass
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Xi-Feng-Hua-Shi granules for diarrhea-predominant irritable bowel syndrome:protocol for a randomized,double-blind,placebo-controlled multi-center clinical trial
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作者 Hui Li Kai-Li Luo +13 位作者 Dan Wang Yun Huang Xiao-Mei Xu Xue Zou Ren-Jing Qiu Ting Chen Chuan-Wang Zhu Jie Li Yong-Shuang Wang Han-Lin Wang Zu Yang Yong-Yue Wei Yao-Zhou Tian Xu-Dong Tang 《Clinical Research Communications》 2022年第2期15-21,共7页
Background:Irritable bowel syndrome(IBS)is a common functional bowel disorder that can severely affect the quality of life of patients.Limited drugs have been reported for modern medical IBS treatment.The advantages o... Background:Irritable bowel syndrome(IBS)is a common functional bowel disorder that can severely affect the quality of life of patients.Limited drugs have been reported for modern medical IBS treatment.The advantages of traditional Chinese medicine(TCM)treatment are gradually becoming prominent.Xi-Feng-Hua-Shi granules have been clinically used for diarrhea-predominant IBS(IBS-D)treatment for many years in TCM practice.Thus,this study aimed to further verify the effectiveness and safety of Xi-Feng-Hua-Shi(XFHS)granules in IBS-D treatment through a randomized,double-blind,placebo-controlled multi-center clinical trial and provide high-quality evidence for its effectiveness and safety in treatment,as well as provide a basis for clinical rational drug use and explore new clinical IBS-D treatment plans.Methods:A randomized,double-blind,placebo-controlled multi-center clinical trial will be performed in 23 hospitals.A total of 300 participants will be randomly divided into the experimental group(prescribed with XFHS granules)and the control group(prescribed with the placebo granules),with 150 participants in each group.The appearance,shape,color,and taste of the placebo granules are the same as those of XFHS granules.All participants will receive a 4-week treatment and a 6-month follow-up.The primary outcome is the overall clinical efficacy;the secondary outcomes are the IBS-Symptom Severity Score(IBS-SSS),TCM Syndrome Evaluation,and the IBS-Quality of Life(IBS-QoL)score,mental state assessment,and recurrence rate.Outcome measures(including primary and secondary outcome measures)are collected at baseline,as well as 2,4,16,and 28 weeks post-intervention.Discussion:This randomized,placebo-controlled,multi-center trial may provide high-quality evidence for the clinical XFHS granule efficacy in IBS-D treatment.Additionally,this study will conduct safety evaluations to provide a basis for clinical rational drug use. 展开更多
关键词 Xi-Feng-Hua-Shi granules diarrhea-predominant irritable bowel syndrome Randomized double-blind placebo-controlled multi-center clinical trial protocol
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