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Nuclear charge radius predictions by kernel ridge regression with odd-even effects
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作者 Lu Tang Zhen-Hua Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期94-102,共9页
The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear models.These are:(i)the isospin-dependent A^(... The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear models.These are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-Bogoliubov(RCHB)theory,(iii)Hartree-Fock-Bogoliubov(HFB)model HFB25,(iv)the Weizsacker-Skyrme(WS)model WS*,and(v)HFB25*model.In the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFB25 models,respectively.For each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number Z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR method.The best among them was the RCHB model,with a root-mean-square deviation of 0.0092 fm.The extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR method.The strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=126 and 82 shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method. 展开更多
关键词 Nuclear charge radius Machine learning Kernel ridge regression method
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Hydrographic Characteristics and Oceanic Heat Flux in the Upper Arctic Ocean over the Alpha Ridge Observed by the DTOP Platform in 2018 and 2021
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作者 WANG Yongjun LI Tao 《Journal of Ocean University of China》 CAS CSCD 2024年第2期304-316,共13页
In 2018 and 2021,the Drift-Towing Ocean Profilers(DTOP)provided extensive temperature and salinity data on the upper 120m ocean through their drifts over the Alpha Ridge north of the Canada Basin.The thickness and tem... In 2018 and 2021,the Drift-Towing Ocean Profilers(DTOP)provided extensive temperature and salinity data on the upper 120m ocean through their drifts over the Alpha Ridge north of the Canada Basin.The thickness and temperature maximum of Alaska Coastal Water(ACW)ranged from 20m to 40m and-1.5℃to-0.8℃,respectively,and the salinity generally maintained from 30.2 to 32.5.Comparison with World Ocean Atlas 2018’s climatology manifested a 40m-thick and warm ACW roughly ex-ceeding the temperature maximum by 0.4–0.5℃in June–August 2021.This anomalously warm ACW was highly related to the ex-pansion of the Beaufort Gyre in the negative Arctic Oscillation phase.During summer,the under-ice oceanic heat flux F_(w)^(OHF)was elevated,with a maximum value of above 25Wm^(-2).F_(w)^(OHF)was typically low in the freezing season,with an average value of 1.2Wm^(-2).The estimates of upward heat flux contributed by ACW to the sea ice bottom F_(w)^(OHF)were in the range of 3–4Wm^(-2)in June–August 2021,when ACW contained a heat content of more than 80MJm^(-2).The heat loss over this period was driven by a weak stratification upon the ACW layer associated with a surface mixed layer(SML)approaching the ACW core.After autumn,F_(w)^(OHF)was reduced(<2 Wm^(-2))except during rare events when it elevated F_(w)^(OHF)slightly.In addition,the intensive and widespread Ekman suction,which created a violent upwelling north of the Canada Basin,was largely responsible for the substantial cooling and thinning of the ACW layer in the summer of 2021. 展开更多
关键词 Arctic Ocean oceanic heat flux Alaska Coastal Water Alpha ridge
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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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基于Bayesian-Ridge模型的煤炭企业净资产收益率影响因素
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作者 谭旭红 王朕卿 《黑龙江科技大学学报》 CAS 2023年第4期622-628,共7页
为评估各因素对净资产收益的影响程度,以2002—2022年我国上市煤炭企业的相关数据为研究样本,基于机器学习中的Bayesian-Ridge模型进行训练,分析各自变量对因变量的影响程度,并与传统OLS模型进行对比。实验结果表明:在影响因素权重大小... 为评估各因素对净资产收益的影响程度,以2002—2022年我国上市煤炭企业的相关数据为研究样本,基于机器学习中的Bayesian-Ridge模型进行训练,分析各自变量对因变量的影响程度,并与传统OLS模型进行对比。实验结果表明:在影响因素权重大小方面,Bayesian-Ridge模型与OLS模型均显示经营负债比率对净资产收益率影响最大,其次是国有持股比例和营业利润率;在方法层面,随样本点数据增加,Bayesian-Ridge模型可降低先验分布的影响;Bayesian-Ridge模型决定系数R~2为0.002 3,高于OLS模型的0.001 8,在该问题研究中Bayesian-Ridge模型优于OLS模型。 展开更多
关键词 煤炭企业 净资产收益率 Bayesian-ridge模型 OLS模型 因子权重
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Review on the fully mulched ridge–furrow system for sustainable maize production on the semi-arid Loess Plateau 被引量:1
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作者 WANG Jin-bin XIE Jun-hong +1 位作者 LI Ling-ling ADINGO Samuel 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1277-1290,共14页
The fully mulched ridge–furrow(FMRF) system has been widely used on the semi-arid Loess Plateau of China due to its high maize(Zea mays L.) productivity and rainfall use efficiency. However, high outputs under this s... The fully mulched ridge–furrow(FMRF) system has been widely used on the semi-arid Loess Plateau of China due to its high maize(Zea mays L.) productivity and rainfall use efficiency. However, high outputs under this system led to a depletion of soil moisture and soil nutrients, which reduces its sustainability in the long run. Therefore, it is necessary to optimize the system for the sustainable development of agriculture. The development, yield-increasing mechanisms,negative impacts, optimization, and their relations in the FMRF system are reviewed in this paper. We suggest using grain and forage maize varieties instead of regular maize;mulching plastic film in autumn or leaving the mulch after maize harvesting until the next spring, and then removing the old film and mulching new film;combining reduced/notillage with straw return;utilizing crop rotation or intercropping with winter canola(Brassica campestris L.), millet(Setaria italica), or oilseed flax(Linum usitatissimum L.);reducing nitrogen fertilizer and partially replacing chemical fertilizer with organic fertilizer;using biodegradable or weather-resistant film;and implementing mechanized production. These integrations help to establish an environmentally friendly, high quality, and sustainable agricultural system, promote highquality development of dryland farming, and create new opportunities for agricultural development in the semi-arid Loess Plateau. 展开更多
关键词 fully mulched ridge–furrow SYSTEM SEMI-ARID Loess Plateau maize productivity FARMING SYSTEM sustainability
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Mulching broad ridges with a woven polypropylene fabric increases the growth and yield of young pear trees ‘Yuluxiang' in the North China Plain 被引量:1
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作者 Yang Wu Mingde Sun Songzhong Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期414-424,共11页
Unlike traditional ridging, mulching broad ridges with a woven polypropylene fabric (WPF) can reduce soil evaporation during the drought season and avoid long saturation time in the root zone of pear trees during the ... Unlike traditional ridging, mulching broad ridges with a woven polypropylene fabric (WPF) can reduce soil evaporation during the drought season and avoid long saturation time in the root zone of pear trees during the rainy season. In this study, field experiments were conducted from 2017 to 2020 in a pear orchard in the North China Plain to investigate the effects of mulching broad ridges (0.3 m in height and 2 m in width) with WPF on soil temperature and moisture, nitrogen leaching, vegetative and reproductive growth of young pear trees(Pyrus bretschneideri Rehd.‘Yuluxiang’). The experiments involved two treatments, namely, control (traditional no-ridge planting without mulching) and mulching broad ridges with WPF (RM treatment). The results showed that the RM treatment increased soil moisture and temperature and decreased nitrogen leaching, resulting in vigorous growth of the young pear trees. Moreover, the RM treatment increased the tree trunk cross-sectional area and height of the young pear trees by 37%and 8%in 2020, respectively. The nitrate nitrogen content at the soil layer depth of 0-30 cm was significantly higher in the RM than that in control. Furthermore, the RM treatment significantly increased the fruit yield due to larger tree size. In addition, compared with control, significantly higher fruit soluble solid content of RM treatment was detected in 2020. High precipitation (423 mm) occurred during fruit enlargement stage in 2020, RM treatment decreased the rainfall infiltration in the ridge and the soil moisture in root region, resulting in the improvement of fruit quality, compared with control.Therefore, mulching broad ridges with WPF can be implemented to increase soil moisture during drought season, soil temperature, and nitrate nitrogen content, thereby improving the growth and fruit yield of young pear trees. Additionally, it can reduce soil moisture in the root zone during the rainy season and improve the fruit quality of the trees. Finally, it can reduce nitrate nitrogen leaching, thereby reducing environmental pollution. 展开更多
关键词 Pyrus bretschneideri Rehd Mulching broad ridges Trunk cross-sectional area Yield efficiency Soil water content Soil temperature
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Origin of submarine canyon-channel systems along the middle segment of West Mariana Ridge,Philippine Sea
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作者 Guangxu ZHANG Shuang LI +4 位作者 Wei LI Xiujuan WANG Duanxin CHEN Dongdong DONG Wenlong WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期881-896,共16页
Submarine canyon-channel systems have been documented in the Parece Vela Basin,West Mariana Ridge;however,the mechanism of the formation and controlling factors remain poorly understood.Based on high-resolution multib... Submarine canyon-channel systems have been documented in the Parece Vela Basin,West Mariana Ridge;however,the mechanism of the formation and controlling factors remain poorly understood.Based on high-resolution multibeam bathymetric data and two-dimensional(2D)seismic profiles,we identified and mapped the submarine canyon-channel system along the middle segment of West Mariana Ridge in the Philippine Sea.These submarine canyon-channels show a main W-E orientation at depth of 2000–4500 m.They are approximately 72–128 km in length and 1.3–15 km in width,and their canyon heads are adjacent to the seamounts with several branches.The upper reaches of submarine canyon-channels are characterized by deeply incised,narrow,V-shaped thalwegs,suggesting the powerful erosion of gravity flows.The distinguished sediment waves are suggested to be resulted from the interaction of turbidity currents and seafloor.Our observations demonstrate that gravity flows originated from the collapses of seamount flanks plays a vital role in developing the submarine canyonchannel system along the West Mariana Ridge.This work provides better understanding of erosion,transport,and deposition of sediments from subducting ridges to deep-water basins,and also new insights into the origin and evolution of submarine canyon-channel systems along subducting ridges. 展开更多
关键词 submarine canyon-channel system gravity flow subducting ridges West Mariana ridge
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Export of Greenland Sea water across the Mohn Ridge induced by summer storms
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作者 Xusiyang Shen Jinping Zhao +4 位作者 Xiaoyu Wang Tore Hattermann Wenqi Shi Long Lin Ping Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期17-28,共12页
The Mohn Ridge separates the Greenland Sea and the Lofoten Basin.Previous studies identified the export across the Mohn Ridge(EMR)from the Greenland Basin into the Lofoten Basin using water mass analysis and the trace... The Mohn Ridge separates the Greenland Sea and the Lofoten Basin.Previous studies identified the export across the Mohn Ridge(EMR)from the Greenland Basin into the Lofoten Basin using water mass analysis and the tracer diffusion method,but there is still lack of direct current measurements.A surface mooring with four current meters was deployed on the Mohn Ridge from June 5 to June 18 in 2015,when three cyclones passed in the adjacent area.In the absence of cyclones,the flow on the Mohn Ridge was northeastward,parallel to the ridge.When cyclones appeared,the EMR occurred to transport Greenland Sea water into the Lofoten Basin.The probable mechanism is the sea level height variation caused by the perturbation of the low pressure of cyclones,which yields an outward pressure gradient force to drive the outflow.Our results suggest that the outflow is intermittent and only happens during cyclone activities.The annual mean volume flux of EMR was roughly estimated by the limited data,which is about 3.8×10^(6)m^(3)/s,a little bit smaller than the estimation based on volume conservation.The results indicate that the contribution of the cyclonic storms to EMR is a greatly important mechanism that potentially influences the global thermohaline circulation through the Greenland-Scotland Ridge overflow. 展开更多
关键词 Mohn ridge current measurement CYCLONE
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Critical thresholds for stage division of water erosion process in different ridge systems in mollisol region of Northeast China
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作者 JIAO Jian QIN Wei +3 位作者 LI Kun-heng XU Hai-chao YIN Zhe HOU Shu-yan 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1540-1560,共21页
Extreme rainfall events on a slope under ridge tillage systems cause concentrated stream soil loss.To analyse the critical thresholds for different stages of water erosion process of ridge systems,simulated rainfall-e... Extreme rainfall events on a slope under ridge tillage systems cause concentrated stream soil loss.To analyse the critical thresholds for different stages of water erosion process of ridge systems,simulated rainfall-erosion experiments for the contour wide ridge(CWR),contour narrow ridge(CNR),longitudinal wide ridge(LWR),and longitudinal narrow ridge(LNR)were conducted under four rainfall intensities,with slope gradients of 3°and 5°.For the runoff event,the runoff depth order was LNR>LWR>CWR>CNR;the soil loss order was CNR>LNR>CWR>LWR.The product of slope factor(S)and rainfall erosivity(R)or runoff depth(D),can be adopted as critical thresholds for different stages of runoff and soil erosion process.For the longitudinal ridge systems,R values were provided for LWR and LNR and were the beginning of sheet flow,whereas the product of rainfall erosivity and slope factor(RS)values were provided for LWR and LNR as the beginning of the accelerated concentrated flow.For the contour ridge systems,R values were provided for CWR and CNR as critical thresholds for the beginning of overflow.The product of runoff depth and slope factor(DS)values were 9.98 and 7.73 mm for CWR and CNR,respectively,and were critical thresholds for the beginning of ridge failure;the DS values were 18.45 and 12.75 mm for CWR and CNR,respectively,and were critical thresholds for the beginning of the formation of ephemeral gully erosion.The critical thresholds can distinguish different stages of soil erosion process modelling. 展开更多
关键词 RUNOFF Soil loss THRESHOLD ridge failure Artificial rainfall simulation
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Geological context and vents morphology in the ultramafic-hosted Tianxiu field, Carlsberg Ridge
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作者 Jin Liang Chunhui Tao +6 位作者 Xiangxin Wang Cheng Su Wei Gao Yadong Zhou Weikun Xu Xiaohe Liu Zhongjun Ding 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第9期62-70,共9页
The Tianxiu hydrothermal field(TXHF) located on Carlsberg Ridge is one of the few active ultramafic-hosted venting systems known in the Indian Ocean. Despite numerous investigations, there is limited understanding of ... The Tianxiu hydrothermal field(TXHF) located on Carlsberg Ridge is one of the few active ultramafic-hosted venting systems known in the Indian Ocean. Despite numerous investigations, there is limited understanding of its sulfide structure morphology, and the factors controlling the formation of TXHF are poorly understood. In this study, we conducted detailed seafloor mapping using visual data obtained by dives using the human-occupied vehicle(HOV) Jiaolong. The TXHF is found to be an active, off-axis, ultramafic-hosted, high-temperature hydrothermal area in which serpentine peridotite is exposed. Two main hydrothermal sites were identified, i.e., P and Y, both of which feature a complex of chimneys and beehive diffusers constituting a “chimney jungle” and isolated large steep-sided structures developed on flat-lying sulfide mounds. In addition, some sporadic inactive chimneys and outcrops of hydrothermal deposits were noted. The chimneys are rich in Fe and Zn sulfide, and lack the central fluid channel formed by focused high-temperature fluid flow. Hydrothermal venting at TXHF is likely related to low-angle detachment faults that focus and transport hydrothermal fluids away from a heat source along the valley wall. Our results complement and expand upon previous works concerning sulfide chimney morphology and their corresponding mineral paragenesis in ultramafic-hosted hydrothermal systems in the Indian Ocean and further our understanding of modern seafloor hydrothermal systems. 展开更多
关键词 hydrothermal activity sulfide accumulation MORPHOLOGY ultramafic-hosted Carlsberg ridge
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Ridge regression energy levels calculation of neutral ytterbium(Z=70)
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作者 余雨姝 杨晨 蒋刚 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期196-204,共9页
In view of the difficulty in calculating the atomic structure parameters of high-Z elements,the Hartree–Fock with relativistic corrections(HFR)theory in combination with the ridge regression(RR)algorithm rather than ... In view of the difficulty in calculating the atomic structure parameters of high-Z elements,the Hartree–Fock with relativistic corrections(HFR)theory in combination with the ridge regression(RR)algorithm rather than the Cowan code’s least squares fitting(LSF)method is proposed and applied.By analyzing the energy level structure parameters of the HFR theory and using the fitting experimental energy level extrapolation method,some excited state energy levels of the Yb I(Z=70)atom including the 4f open shell are calculated.The advantages of the ridge regression algorithm are demonstrated by comparing it with Cowan code’s LSF results.In addition,the results obtained by the new method are compared with the experimental results and other theoretical results to demonstrate the reliability and accuracy of our approach. 展开更多
关键词 atomic data YTTERBIUM energy levels ridge regression algorithm
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Analysis of Ship Motion in An Ice Ridge Field Based on Empirical Approach
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作者 SONG Ming YUAN Wei +1 位作者 LIU Kun HAN Yue 《China Ocean Engineering》 SCIE EI CSCD 2023年第6期912-922,共11页
The estimation of ship speed in ice ridge fields is important for both route planning and prediction of emergency response time.An analytical method for estimating ship motion in first-year ice ridge is developed base... The estimation of ship speed in ice ridge fields is important for both route planning and prediction of emergency response time.An analytical method for estimating ship motion in first-year ice ridge is developed based on ice resistance models and ship motion equations,in which the effect of ship speed on ridge resistance is taken into account.Two model tests in level ice and one model test in ice ridge for an icebreaking multipurpose vessel are used to validate and benchmark the presented method.The predicted results including level ice resistances,net thrust and ship motion in the ice ridge field are compared with the model test data.The comparisons show that the presented method can generate reasonable results.The effects of input parameters on ship speed,penetration depth and number of necessary rams to transit ridge have been studied.Based on the calibrated model,insights into the ice resistance and the ship motion are obtained.It is found that the energy consumption of the keel obtained by integral calculation of the keel resistance at the penetration distance is with the same magnitude as the result of the maximum keel resistance multiplied by the ridge length.In addition,the effect of ridge width and keel depth on keel resistance and average transit speed is investigated. 展开更多
关键词 ice ridge ice resistance model tests average transit speed
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Formation and modification of wrinkle ridges in the central Tharsis region of Mars as constrained by detailed geomorphological mapping and landsystem analysis
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作者 An Yin YingChi Wang 《Earth and Planetary Physics》 EI CSCD 2023年第2期161-192,共32页
Wrinkle ridges are common landforms documented on all rocky planets and the Moon in the inner solar system.Despite the long research history,their formation mechanisms remain debated.A key unresolved issue is whether ... Wrinkle ridges are common landforms documented on all rocky planets and the Moon in the inner solar system.Despite the long research history,their formation mechanisms remain debated.A key unresolved issue is whether the wrinkle-ridge formation is related to igneous processes.This is because wrinkle ridges are mostly associated in space and possibly in time with the occurrence of flood-basalt volcanism in all cases in the inner solar system.To address this issue,we conducted geomorphological mapping,a topographic-data analysis,and a detailed landform and landsystem analysis of satellite images at a resolution of 25 cm/pixel to 6 m/pixel in the central Tharsis region of Mars.The main results of this work are in the form of(1)a regional geomorphological map at a resolution of 6 m/pixel and(2)a local geomorphological map at a resolution of 50 cm/pixel.Our work suggests the following older-to-younger sequence of geological events in the study area:(1)formation of a northeast-trending mountain range(i.e.,the Thaumasia plateau)along the eastern margin of the Tharsis rise that was created by the Himalayan-style crustal-scale thrusting;(2)coeval volcanic-plateau construction west of the thrusting-induced rising mountain range;(3)eastward-flowing lavas that were sourced from a volcanic plateau to the west terminated at the rising Thaumasia plateau to the east;(4)wrinkle-ridge development by decollement folding of recently emplaced warm,ductile volcanic-lava piles;(5)emplacement of a regionally extensive ice sheet over the central Tharsis region that produced extensive boulder-bearing materials,striated surfaces,and boulder-bearing dendritic-ridge networks possibly representing subglacial eskers;and(6)local deposition of highly concentrated glacial flours resulted in the formation of mantled terrain on plains between wrinkle ridges.Our work supports the early suggestion that the Tharsis wrinkle ridges were created by horizontal shortening induced by crustal-scale tectonic processes.In detail,however,the occurrence of flow-front-like fold margins associated with many mapped wrinkle ridges suggests the involvement of ductile-flow deformation during ridge formation.We attribute the flow-like fold fronts to ductile deformation of thermally weakened lava piles that were emplaced during or immediately before the folding event.Our compression-induced wrinkle-ridge model also differs from the early hypotheses in that the thin-skinned folding is associated with basement subduction,which explains the lack of coeval and parallel folding and extensional faulting associated with wrinkle ridge formation in the study area.Post-folding glacial modification means that the present wrinkle-ridge morphologies may differ significantly from the original fold shapes,which prevents the utility of using topographic profiles across wrinkle ridges for inverting the underlying thrust geometries. 展开更多
关键词 planetary tectonics wrinkle ridges Tharsis rise GLACIATION
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Clay mineral distribution characteristics of surface sediments in the South Mid-Atlantic Ridge
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作者 Qiannan HU Chuanshun LI +4 位作者 Baoju YANG Xisheng FANG Huahua LÜ Xuefa SHI Jihua LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期897-908,共12页
Clay minerals are usually considered as important indicators to identify sources in both terrigenous and marine sediments.In particular,clay minerals in metalliferous sediments(MS)have long been studied in global ocea... Clay minerals are usually considered as important indicators to identify sources in both terrigenous and marine sediments.In particular,clay minerals in metalliferous sediments(MS)have long been studied in global oceans except in South Mid-Atlantic Ridge(SMAR)due to limited explorations.Thus,32 MS and 34 non-MS(NMS)samples were analyzed to clarify the distribution characteristics and mineral compositions of clay minerals.All the sediments were collected along the SMAR between 12°S and 27°S.After removal of organic matter and carbonate,clay fractions(<2μm)were investigated by Xray diffraction(XRD)analysis.Results show that clay mineral assemblages of surface MS consist dominantly of smectite,less abundant illite,chlorite,and kaolinite in average weight percentage of 30%,21%,18%,and 16%,respectively.On the other hand,clay mineral assemblages in the NMS consist mainly of illite,less abundant kaolinite,chlorite,and very scarce smectite in average weight percentage of 47%,29%,24%,and 0.2%,respectively.The clay fractions in MS are mainly composed of amorphous or poorly crystallized Fe/Mn oxyhydroxides,clay mineral,quartz,and plagioclase.However,the counterparts in the NMS are mainly composed of well-crystallized clay minerals,quartz,and plagioclase without the presence of Fe/Mn oxyhydroxides.It is suggested that most of the illite,kaolinite,and chlorite in both MS and NMS are likely aeolian dust in origin from South Africa continent.In addition,the abundance of kaolinite dominates the clay mineral assemblage at low latitudes,where the intensive chemical weathering of continental source rocks facilitating the formation of kaolinite.In terms of smectite,it is indicated of authigenic origin in consideration of only smectite is available in several MS and the absence in NMS.Moreover,the MS samples with only smectite available are always accompanied by goethite.Therefore,it is assumed that most of smectite occurred in studied area is the results of interaction between hydrothermal Fe-oxyhydroxide,silica,and seawater. 展开更多
关键词 metalliferous sediment South Mid-Atlantic ridge(SMAR) clay mineral SMECTITE
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Minimally Invasive Maxillofacial Surgery Using Digital Work Surgery: A Case of Alveolar Ridge Reconstruction after Maxillary Cystectomy
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作者 Toshiyuki Kataoka Kei Amemiya +2 位作者 Erika Tajima Akira Nose Toshihiro Okamoto 《Open Journal of Stomatology》 2023年第10期323-333,共11页
Introduction: Iliac particulate cancellous bone and marrow (PCBM) is commonly used as a high-quality reconstruction material;however, PCBM cannot be extracted in sufficient amounts to meet demand. To determine the app... Introduction: Iliac particulate cancellous bone and marrow (PCBM) is commonly used as a high-quality reconstruction material;however, PCBM cannot be extracted in sufficient amounts to meet demand. To determine the appropriate amount of iliac PCBM to be collected, we used digital technology to measure the volume required for jaw reconstruction before surgery. Clinical Case: The patient, a 23-year-old man, underwent surgery for a calcifying odontogenic cyst. A maxillary cyst occupied the left anterior-premolar region (tooth 21 - 25) and the deciduous canine remained;a permanent canine was included in the cyst. We planned to preserve the teeth except for the impacted canine, completely excise the maxillary cyst, and preserve the alveolar ridge morphology. Preoperative digital imaging was used to determine the amount of alveolar ridge reconstruction required and accordingly determine the amount of iliac cancellous bone to be harvested. We used a titanium mesh tray and grafts of iliac particulate cancellous bone and marrow to reconstruct the alveolar ridge. The amount of iliac cancellous bone that needed to be collected was clarified and the supply amount could be collected in just the right amount;thus, the cortical bone of the iliac inner plate could be preserved. The alveolar bone morphology was reconstructed to allow the placement of dental implants as per the preoperative digital surgery. Three years after the operation, no sign of recurrence has been observed. Conclusion: Minimally invasive surgery was performed by clarifying the amount of iliac cancellous bone graft that needs to be harvested, which improved the accuracy of surgery. 展开更多
关键词 Alveolar ridge Reconstruction Digital Work Surgery Iliac Cancellous Bone Graft Minimally Invasive Surgery
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Aseismic ridge subduction and flat subduction:Insights from three-dimensional numerical models
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作者 Hui Zhao Wei Leng 《Earth and Planetary Physics》 EI CSCD 2023年第2期269-281,共13页
Flat subduction can significantly influence the distribution of volcanism,stress state,and surface topography of the overriding plate.However,the mechanisms for inducing flat subduction remain controversial.Previous t... Flat subduction can significantly influence the distribution of volcanism,stress state,and surface topography of the overriding plate.However,the mechanisms for inducing flat subduction remain controversial.Previous two-dimensional(2-D)numerical models and laboratory analogue models suggested that a buoyant impactor(aseismic ridge,oceanic plateau,or the like)may induce flat subduction.However,three-dimensional(3-D)systematic studies on the relationship between flat subduction and buoyant blocks are still lacking.Here,we use a 3-D numerical model to investigate the influence of the aseismic ridge,especially its width(which is difficult to consider in 2-D numerical models),on the formation of flat subduction.Our model results suggest that the aseismic ridge needs to be wide and thick enough to induce flat subduction,a condition that is difficult to satisfy on the Earth.We also find that the subduction of an aseismic ridge parallel to the trench or a double aseismic ridge normal to the trench has a similar effect on super-wide aseismic ridge subduction in terms of causing flat subduction,which can explain the flat subduction observed beneath regions such as Chile and Peru. 展开更多
关键词 flat subduction aseismic ridge oceanic plateau 3-D numerical simulation
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Ridge回归模型下金融支持对安徽农村产业融合的影响
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作者 程艳 柏锦凤 《滁州学院学报》 2023年第1期33-38,共6页
农村一二三产业融合发展是农业农村转型发展的根本选择,对实施乡村振兴战略、全面建设社会主义现代化国家具有重大意义。本文以安徽省为切入点,构建农村产业融合评价体系,通过熵值法测度安徽农村产业融合发展水平;运用Ridge回归模型分... 农村一二三产业融合发展是农业农村转型发展的根本选择,对实施乡村振兴战略、全面建设社会主义现代化国家具有重大意义。本文以安徽省为切入点,构建农村产业融合评价体系,通过熵值法测度安徽农村产业融合发展水平;运用Ridge回归模型分析金融支持对安徽农村产业融合的影响。实证研究结果表明,政府财政支持、金融机构支农力度、金融业发展水平对促进安徽省农村产业融合发展有着正向作用。本文在此基础上提出了相关政策建议。 展开更多
关键词 金融支持 农村产业融合 ridge回归模型 熵值法
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Record of hydrothermal activity in the Yuhuang hydrothermal field and its implications for the Southwest Indian Ridge:evidence from sulfide chronology
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作者 Weifang Yang Chunhui Tao +6 位作者 Shili Liao Jin Liang Wei Li Teng Ding Ágata Alveirinho Dias Xuefeng Wang Lisheng Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期59-68,共10页
The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previ... The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide deposits.However,the sulfide chronology and hydrothermal activity of the YHF remain poorly constrained.In this study,mineralogical analyses and 230Th/U dating were performed.Hydrothermal activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the YHF.The 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the SWIR.Hydrothermal activity in the SWIR has been relatively active over the past20 ka.In contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in duration.The maximum activity occurred at 15–11 ka,9–7 ka,6–0.2 ka.There was a slight positive correlation between the maximal age and estimated surface area or estimated tonnage.The minimum mass accumulation rate of YHF is about 278 t/a,which is higher than most HFs related to ultramafic systems.The ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)deposits.The results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges. 展开更多
关键词 Southwest Indian ridge seafloor massive sulfides 230Th/U dating hydrothermal activity mass accumulation
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Revisiting Akaike’s Final Prediction Error and the Generalized Cross Validation Criteria in Regression from the Same Perspective: From Least Squares to Ridge Regression and Smoothing Splines
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作者 Jean Raphael Ndzinga Mvondo Eugène-Patrice Ndong Nguéma 《Open Journal of Statistics》 2023年第5期694-716,共23页
In regression, despite being both aimed at estimating the Mean Squared Prediction Error (MSPE), Akaike’s Final Prediction Error (FPE) and the Generalized Cross Validation (GCV) selection criteria are usually derived ... In regression, despite being both aimed at estimating the Mean Squared Prediction Error (MSPE), Akaike’s Final Prediction Error (FPE) and the Generalized Cross Validation (GCV) selection criteria are usually derived from two quite different perspectives. Here, settling on the most commonly accepted definition of the MSPE as the expectation of the squared prediction error loss, we provide theoretical expressions for it, valid for any linear model (LM) fitter, be it under random or non random designs. Specializing these MSPE expressions for each of them, we are able to derive closed formulas of the MSPE for some of the most popular LM fitters: Ordinary Least Squares (OLS), with or without a full column rank design matrix;Ordinary and Generalized Ridge regression, the latter embedding smoothing splines fitting. For each of these LM fitters, we then deduce a computable estimate of the MSPE which turns out to coincide with Akaike’s FPE. Using a slight variation, we similarly get a class of MSPE estimates coinciding with the classical GCV formula for those same LM fitters. 展开更多
关键词 Linear Model Mean Squared Prediction Error Final Prediction Error Generalized Cross Validation Least Squares ridge Regression
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一种基于核ridge回归的解耦控制系统 被引量:2
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作者 全勇 杨杰 《上海交通大学学报》 EI CAS CSCD 北大核心 2003年第9期1421-1425,共5页
提出了一种新的基于核ridge回归的解耦方法.该方法具有传统径向基(RBF)神经网络解耦方法对被控对象数学模型依赖性小的特点,同时又能有效地克服RBF神经网络解耦方法对训练样本要求高、噪声敏感和解耦速度慢的缺点,经核ridge解耦器补偿... 提出了一种新的基于核ridge回归的解耦方法.该方法具有传统径向基(RBF)神经网络解耦方法对被控对象数学模型依赖性小的特点,同时又能有效地克服RBF神经网络解耦方法对训练样本要求高、噪声敏感和解耦速度慢的缺点,经核ridge解耦器补偿后的控制系统具有被调节量和调节量之间耦合作用小、动态特性好、稳定性强的优点.补偿后的控制系统具有很强的校正能力,对外界各种干扰也有较强的解耦效果和控制质量.仿真试验表明,采用核ridge解耦器的多变量控制系统能够有效地解除系统各变量之间的耦合作用,且结构简单、易于实现,大大增强了解耦控制系统的实用性能. 展开更多
关键词 解耦 多变量控制系统 ridge回归
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