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Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration
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作者 Jin-Min Song Xin Jin +10 位作者 Zhong Luo Shu-Gen Liu Shao-Bo Liu Xing-Zhi Ma Zhi-Wu Li Xue-Song Lu Ling-Li Zhao Ke-Ran Li Jia-Xin Ren Li-Zhou Tian Hao-Shuang Deng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期806-822,共17页
Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional p... Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain lateral comparison profile and seismic reflection structures in the 2D seismic section, which can provide references for future worldwide exploration. Microbial mounds with larger buildups and thicker vertical reservoirs are typically targeted on the windward margin, while small-sized microbial mounds and flats with better lateral connections are typically focused on the leeward margin. 展开更多
关键词 Sichuan Basin The Member Deng-2 marginal microbial mound-bank complex Depositional model Exploration implications
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Modeling Water Quality Impacts of Growing Corn, Switchgrass, and <i>Miscanthus</i>on Marginal Soils 被引量:1
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作者 Mark A. Thomas Laurent M. Ahiablame +1 位作者 Bernard A. Engel Indrajeet Chaubey 《Journal of Water Resource and Protection》 2014年第14期1352-1368,共17页
The goal of the study was to model water quality impacts of growing perennial grasses on marginal soils. The GLEAMS-NAPRA and RUSLE models were used to simulate long-term surface runoff, percolation, erosion, total ph... The goal of the study was to model water quality impacts of growing perennial grasses on marginal soils. The GLEAMS-NAPRA and RUSLE models were used to simulate long-term surface runoff, percolation, erosion, total phosphorus (TP), and nitrate (NO3-N) losses associated with the production of corn-based bioenergy systems (i.e. conventional tillage corn and corn grain plus stover removal), switchgrass and Miscanthus on three marginal quality soils and one good quality soil in Indiana. Simulations showed that switchgrass and Miscanthus had no effect on annual runoff, but decreased percolation by at least 17%. Results also suggested a potential for reduction in erosion for Miscanthus across the soil types examined when compared to corn-based bioenergy production. The production of switchgrass and Miscanthus did not have significant effects on the simulated TP and NO3-N losses in runoff compared to corn production systems. Nitrates leached from fertilized Miscanthus production were approximately 90% lower than NO3-N leached from the production of fertilized switchgrass and corn systems. Additional studies are needed to better understand the hydrology, erosion and nutrient responses of Miscanthus and switchgrass production to meet bioenergy demands. 展开更多
关键词 Water Quality modelING Perennial Grass Runoff Biofuels marginal Lands GLEAMS-NAPRA
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Physical modeling of salt structures in the middle south Atlantic marginal basins and their controlling factors 被引量:3
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作者 YU Yixin TAO Chongzhi +3 位作者 SHI Shuaiyu YIN Jinyin WU Changwu LIU Jingjing 《Petroleum Exploration and Development》 CSCD 2021年第1期136-145,共10页
With many types of salt structures developed in the Lower Cretaceous Aptian Formation,the passive continental marginal basins in the middle segment of the south Atlantic are hot areas of deep-water petroleum explorati... With many types of salt structures developed in the Lower Cretaceous Aptian Formation,the passive continental marginal basins in the middle segment of the south Atlantic are hot areas of deep-water petroleum exploration.Based on analysis of differential deformations of salt structures,the influences of the inclination of subsalt slope,subsalt topographic reliefs and basement uplifting on the formation of salt structures were analyzed by physical modeling in this work.The experimental results show that the subsalt slopes in the middle West Africa basins are steeper,so the salt rock is likely to rapidly flow towards the ocean to form larger and fewer salt diapirs.In the Santos and Campos basins,the basement uplifts outside the basins are far from the provenances,which is conducive to the intrusion and accumulation of salt rock on the top of the basement uplifts.In contrast,in the middle West Africa,the basement uplifts are close to the basin margin,the residual salt layers above them are thin,and small triangular salt structures develop on both sides of the uplifts.Moreover,the uplifting of the African plate is also conducive to the full development of salt diapirs in the middle West Africa and results in large-scale thrust faults and folds in the front compressional zone. 展开更多
关键词 South Atlantic passive continental margin Lower Cretacous salt structure subsalt framework physical modeling
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A three-dimensional Moho depth model beneath the Yemeni highlands and rifted volcanic margins of the Red Sea and Gulf of Aden, Southwest Arabia
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作者 Amin Noman Al Kadasi 《China Geology》 CAS CSCD 2023年第4期611-622,共12页
Knowing Moho discontinuity undulation is fundamental to understanding mechanisms of lithosphereasthenosphere interaction, extensional tectonism and crustal deformation in volcanic passive margins such as the study are... Knowing Moho discontinuity undulation is fundamental to understanding mechanisms of lithosphereasthenosphere interaction, extensional tectonism and crustal deformation in volcanic passive margins such as the study area, which is located in the southwestern corner of the Arabian Peninsula bounded by the Red Sea and the Gulf of Aden. In this work, a 3D Moho depth model of the study area is constructed for the first time by inverting gravity data from the Earth Gravitational Model(EGM2008) using the ParkerOldenburg algorithm. This model indicates the shallow zone is situated at depths of 20 km to 24 km beneath coastal plains, whereas the deep zone is located below the plateau at depths of 30 km to 35 km and its deepest part coincides mainly with the Dhamar-Rada ’a Quaternary volcanic field. The results also indicate two channels of hot magmatic materials joining both the Sana’a-Amran Quaternary volcanic field and the Late Miocene Jabal An Nar volcanic area with the Dhamar-Rada’a volcanic field. This conclusion is supported by the widespread geothermal activity(of mantle origin) distributed along these channels,isotopic data, and the upper mantle low velocity zones indicated by earlier studies. 展开更多
关键词 Bouguer gravity anomaly Earth gravitational model(EGM2008) Moho discontinuity Mantle upwelling Lithosphere-asthenosphere interaction Volcanic passive margin ISOSTASY Gulf of Aden Red Sea Arabian Peninsula
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Marginalized cubature Kalman filtering algorithm based on linear/nonlinear mixed-Gaussian model
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作者 Hu Yumei Hu Zhentao Jin Yong 《High Technology Letters》 EI CAS 2018年第4期362-368,共7页
Aiming at improving the estimation accuracy and real-time of nonlinear system with linear Gaussian sub-structure,a novel marginalized cubature Kalman filter is proposed in Bayesian estimation framework. Firstly,the ma... Aiming at improving the estimation accuracy and real-time of nonlinear system with linear Gaussian sub-structure,a novel marginalized cubature Kalman filter is proposed in Bayesian estimation framework. Firstly,the marginalized technique is adopted to model the target system dynamics with nonlinear state and linear state separately,and the two parts are estimated by cubature Kalman filter and standard Kalman filter respectively. Therefore,the linear part avoids the generation and propagation process of cubature points. Accordingly,the computational complexity is reduced.Meanwhile,the accuracy of state estimation is improved by taking the difference of nonlinear state estimation as the measurement of linear state. Furthermore,the computational complexity of marginalized cubature Kalman filter is discussed by calculating the number of floating-point operation. Finally,simulation experiments and analysis show that the proposed algorithm can improve the performance of filtering precision and real-time effectively in target tracking system. 展开更多
关键词 state estimation marginalized modeling mixed-Gaussian model CUBATURE KALMAN FILTER
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Zero Truncated Bivariate Poisson Model: Marginal-Conditional Modeling Approach with an Application to Traffic Accident Data
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作者 Rafiqul I. Chowdhury M. Ataharul Islam 《Applied Mathematics》 2016年第14期1589-1598,共11页
A new covariate dependent zero-truncated bivariate Poisson model is proposed in this paper employing generalized linear model. A marginal-conditional approach is used to show the bivariate model. The proposed model wi... A new covariate dependent zero-truncated bivariate Poisson model is proposed in this paper employing generalized linear model. A marginal-conditional approach is used to show the bivariate model. The proposed model with estimation procedure and tests for goodness-of-fit and under (or over) dispersion are shown and applied to road safety data. Two correlated outcome variables considered in this study are number of cars involved in an accident and number of casualties for given number of cars. 展开更多
关键词 Bivariate Poisson Conditional model Generalized Linear model marginal model Road Safety Data Zero-Truncated
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Causal inference with marginal structural modeling for longitudinal data in laparoscopic surgery: A technical note
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作者 Zhongheng Zhang Peng Jin +7 位作者 Menglin Feng Jie Yang Jiajie Huang Lin Chen Ping Xu Jian Sun Caibao Hu Yucai Hong 《Laparoscopic, Endoscopic and Robotic Surgery》 2022年第4期146-152,共7页
Causal inference prevails in the field of laparoscopic surgery.Once the causality between an intervention and outcome is established,the intervention can be applied to a target population to improve clinical outcomes.... Causal inference prevails in the field of laparoscopic surgery.Once the causality between an intervention and outcome is established,the intervention can be applied to a target population to improve clinical outcomes.In many clinical scenarios,interventions are applied longitudinally in response to patients’conditions.Such longitudinal data comprise static variables,such as age,gender,and comorbidities;and dynamic variables,such as the treatment regime,laboratory variables,and vital signs.Some dynamic variables can act as both the confounder and mediator for the effect of an intervention on the outcome;in such cases,simple adjustment with a conventional regression model will bias the effect sizes.To address this,numerous statistical methods are being developed for causal inference;these include,but are not limited to,the structural marginal Cox regression model,dynamic treatment regime,and Cox regression model with time-varying covariates.This technical note provides a gentle introduction to such models and illustrates their use with an example in the field of laparoscopic surgery. 展开更多
关键词 Causal inference Laparoscopic surgery Machine learning marginal structural modeling
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Marginal Conceptual Predictive Statistic for Mixed Model Selection
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作者 Cheng Wenren Junfeng Shang Juming Pan 《Open Journal of Statistics》 2016年第2期239-253,共15页
We focus on the development of model selection criteria in linear mixed models. In particular, we propose the model selection criteria following the Mallows’ Conceptual Predictive Statistic (Cp) [1] [2] in linear mix... We focus on the development of model selection criteria in linear mixed models. In particular, we propose the model selection criteria following the Mallows’ Conceptual Predictive Statistic (Cp) [1] [2] in linear mixed models. When correlation exists between the observations in data, the normal Gauss discrepancy in univariate case is not appropriate to measure the distance between the true model and a candidate model. Instead, we define a marginal Gauss discrepancy which takes the correlation into account in the mixed models. The model selection criterion, marginal Cp, called MCp, serves as an asymptotically unbiased estimator of the expected marginal Gauss discrepancy. An improvement of MCp, called IMCp, is then derived and proved to be a more accurate estimator of the expected marginal Gauss discrepancy than MCp. The performance of the proposed criteria is investigated in a simulation study. The simulation results show that in small samples, the proposed criteria outperform the Akaike Information Criteria (AIC) [3] [4] and Bayesian Information Criterion (BIC) [5] in selecting the correct model;in large samples, their performance is competitive. Further, the proposed criteria perform significantly better for highly correlated response data than for weakly correlated data. 展开更多
关键词 Mixed model Selection marginal Cp Improved marginal Cp marginal Gauss Discrepancy Linear Mixed model
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Geochemical characteristics and genetic model of dolomite reservoirs in the eastern margin of the Pre-Caspian Basin 被引量:13
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作者 Wang Shuqin Zhao Lun +2 位作者 Cheng Xubin Fan Zifei He Ling 《Petroleum Science》 SCIE CAS CSCD 2012年第2期161-169,共9页
The widespread Carboniferous KT-I dolomite in the eastern margin of the Pre-Caspian Basin is an important hydrocarbon reservoir. The dolomite lithology is dominated by crystalline dolomite. The δ18O values range from... The widespread Carboniferous KT-I dolomite in the eastern margin of the Pre-Caspian Basin is an important hydrocarbon reservoir. The dolomite lithology is dominated by crystalline dolomite. The δ18O values range from -6.71‰ to 2.45‰, and average 0.063‰, obviously larger than -2.5‰, indicating low-temperature dolomite of evaporation origin. Stable strontium isotope ratios (87Sr/86Sr) range from 0.70829 to 0.70875 and average 0.708365, very consistent with 87Sr/86Sr ratios in Carboniferous seawater. Chemical analysis of Ca and Mg elements shows that the dolomite has 9.1 mole% excess Ca or even higher before stabilization. The degree of order of dolomite is medium–slightly poor, varying in a range of 0.336-0.504 and averaging 0.417. It suggests that the dolomite formed under near-surface conditions. There are two models for the origin of the Carboniferous KT-I dolomite reservoir. These are 1) the evaporation concentration – weathering crust model and 2) the shoal facies – seepage reflux model. The former is mainly developed in restricted platforms – evaporate platforms of restricted marine deposition environments with a representation of dolomite associated with gypsum and mudstone. The latter mainly formed in platform edge shoals and intra-platform shoals and is controlled by dolomitization due to high salinity sea water influx from adjacent restricted sea or evaporate platform. 展开更多
关键词 ISOTOPE DOLOMITE CARBONIFEROUS genetic model eastern margin of Pre-Caspian Basin
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Aseismic negative dislocation model and deformation analysis of crustal horizontal movement during 1999--2001 in the northeast margin of Qinghai-Xizang block 被引量:1
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作者 张希 江在森 +2 位作者 王琪 王双绪 张晓亮 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第4期395-403,共9页
Through numerical simulation for GPS data, aseismic negative dislocation model for crustal horizontal movement during 1999~2001 in the northeast margin of Qinghai-Xizang block is presented, combined with the spatial d... Through numerical simulation for GPS data, aseismic negative dislocation model for crustal horizontal movement during 1999~2001 in the northeast margin of Qinghai-Xizang block is presented, combined with the spatial distribution of apparent strain field in this area, the characteristics of motion and deformation of active blocks and their boundary faults, together with the place and intensity of strain accumulation are analyzed. It is shown that: a) 9 active blocks appeared totally clockwise motion from eastward by north to eastward by south. Obvious sinistral strike-slip and NE-NEE relative compressive motion between the blocks separated by Qilianshan-Haiyuan fault zone was discovered; b) 20 fault segments (most of them showed compression) locked the relative motion between blocks to varying degrees, among the total, the mid-east segment of Qilianshan fault (containing the place where it meets Riyueshan-Lajishan fault) and the place where it meets Haiyuan fault and Zhuanglanghe fault, more favored accumulation of strain. Moreover, the region where Riyueshan-Lajishan fault meets north boundary of Qaidam block may have strain accumulation to some degree. c) Obtained magnitude of block velocities and locking of their boundaries were less than relevant results for observation in the period of 1993~1999. 展开更多
关键词 the northeast margin of Qinghai-Xizang block GPS crustal horizontal movement aseismic negative dislocation model apparent strain field
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Numerical modeling of the development of southeastern Red Sea continental margin
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作者 Sunil Kumar Dwivedi Daigoro Hayashi 《Earthquake Science》 CSCD 2009年第3期239-249,共11页
The Red Sea continental margin (RSCM) corresponds to a wide hinge zone between Red Sea and Arabian plate. This margin has been studied through geological and geophysical observations primarily in regard to the evolu... The Red Sea continental margin (RSCM) corresponds to a wide hinge zone between Red Sea and Arabian plate. This margin has been studied through geological and geophysical observations primarily in regard to the evolution of Red Sea rift. This margin is characterized by occurrence of thin sediments, significant onshore uplift, tectonic subsidence of the offshore sedimentary basin, active faulting and seismicity. Studies indicate that sedimentary sequences of the margin are deformed by faults and folds resulting from at least two phases of extension and a phase of uplift. During the two phases of extension due to regional plate stress the sequence was cut by set of extensional faults. While during the phase of uplift the sequence was deformed by folding and faulting. The present paper aims to clear the structural development of RSCM during these tectonic episodes, taken as particular tectonic event, by two-dimensional finite element modeling on plane strain condition. Elastic theology is assumed for the oceanic, continental and transitional crust along with syntectonic deposits. Stress field, shear stress and fault distribution suggests that mantle plume weakened the crust following rifting due to regional stress and developed the margin. These results are well consistent with those from present seismicity, active faulting and neotectonic studies. 展开更多
关键词 Red Sea rift continental margin numerical modeling SEISMICITY NEOTECTONICS
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Asymmetry Index on Marginal Homogeneity for Square Contingency Tables with Ordered Categories
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作者 Kouji Tahata Kanau Kawasaki Sadao Tomizawa 《Open Journal of Statistics》 2012年第2期198-203,共6页
For square contingency tables with ordered categories, the present paper considers two kinds of weak marginal homogeneity and gives measures to represent the degree of departure from weak marginal homogeneity. The pro... For square contingency tables with ordered categories, the present paper considers two kinds of weak marginal homogeneity and gives measures to represent the degree of departure from weak marginal homogeneity. The proposed measures lie between –1 to 1. When the marginal cumulative logistic model or the extended marginal homogeneity model holds, the proposed measures represent the degree of departure from marginal homogeneity. Using these measures, three kinds of unaided distance vision data are analyzed. 展开更多
关键词 marginal HOMOGENEITY marginal CUMULATIVE Logistic model Measure SQUARE CONTINGENCY Table
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Marginal Expansion Planning of Infrastructure at a Container Terminal
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作者 Keng Bin Loke Ab. Saman Abd. Kader +2 位作者 Mohd. Zamani Ahmad Saharuddin Abdul Hamid Mohamad Rosni Othman 《Open Journal of Marine Science》 2015年第1期99-107,共9页
Globalization push container terminal grown rapidly in decade. To fulfill the future traffic requirement, this study highlights marginal expansion planning of infrastructure in a container terminal. By using marginal ... Globalization push container terminal grown rapidly in decade. To fulfill the future traffic requirement, this study highlights marginal expansion planning of infrastructure in a container terminal. By using marginal approach, the expansion plan can be determine correctly and economically stage by stage. A mathematical model has generated to calculate the expansion size, expansion time, interval of expansion, expansion cost, and significant of expansion for each infrastructure respectively. It recommended determining the expansion plan for each infrastructure respectively. This is because one of the infrastructures needs to be expanding but the other may not. The generated model was verified with others model and validated with case study to investigate the practicability of the model. The model serves as expansion decision making tools to assist port expansion planners. 展开更多
关键词 INFRASTRUCTURE marginal Approach EXPANSION PLAN MATHEMATICAL model EXPANSION SIZE EXPANSION Time
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Evaluation of Potential Productivity of Woody Energy Crops on Marginal Land in China
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作者 WANG Jinzhu GAO Ming +3 位作者 HE Xinhua ZHANG Qian Natamba LEO XU Chang 《Chinese Geographical Science》 SCIE CSCD 2017年第6期963-973,共11页
Energy crops are a basic material in the bioenergy industry, and they can also mitigate carbon emissions and have environ- mental benefits when planted on marginal lands. The aim of this study was to evaluate the pote... Energy crops are a basic material in the bioenergy industry, and they can also mitigate carbon emissions and have environ- mental benefits when planted on marginal lands. The aim of this study was to evaluate the potential productivity of energy crops on marginal lands in China. A mechanistic model, combined with energy crop and land use characteristics, and meteorological and soil parameters, was used to simulate the potential productivity of energy crops. There were three main results. 1) The total marginal land in China was determined to be 104.78 × 106 ha. The 400-mm precipitation boundary line, which is the dividing line between the semi-humid and semi-arid zones in China, also divided the marginal land into shrub land and sparse forest land in the southeast and bare land, bare rock land, and saline alkali land in the northeast. 2) The total area of the marginal land suitable for planting energy crops was determined to be 55.82 × 106 ha, with Xanthoceras sorbifolia and Cerasus humilis mainly grown in the northern China, Jatropha curcas and Comus wilsoniana mainly grown in the southwest and southeast, and Pistacia chinensis mainly grown in the central area, while also having a northeast-southwest zonal distribution. 3) Taking the highest yield in overlapping areas, the potential productivity of target energy crops was determined to be 32.63 × 106 t/yr. Without considering the overlapping areas, the potential productivity was 6.81× 106 t/yr from X. sorbifolia, 8.86× 106t/yr from C. humilis, 7.18 ×106t/yr from J. curcas, 9.55 × 106t/yr from P. chinensis, and 7.78 ×106 t/yr from C. wilsoniana. 展开更多
关键词 energy crop marginal land potential productivity mechanistic model China
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Structural Architecture for Development of Marginal Extensional Sub-Basins in the Red Sea Active Rift Zone
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作者 Reda Amer Mohamed Sultan +1 位作者 Robert Ripperdan John Encarnación 《International Journal of Geosciences》 2012年第1期133-152,共20页
This paper presents a robust kinematic model that describes northern Red Sea and Gulf of Suez rifting and the development of marginal extensional half-graben sub-basins (ESB). A combination of Landsat Enhanced Themati... This paper presents a robust kinematic model that describes northern Red Sea and Gulf of Suez rifting and the development of marginal extensional half-graben sub-basins (ESB). A combination of Landsat Enhanced Thematic Mapper Plus (ETM+) and structural data was used to provide model constraints on the development of rift segments and ESB in the active rift zones. Structural analysis shows rotation and change in strike of rift-bounding faults. The model describes the northern Red Sea region as a poly-phase rift system initiated by late Oligocene (30 - 24 Ma) orthogonal rifting and the development of marginal ESB (now inland ESB), followed by oblique rifting and flank uplift during the early Miocene (24 - 18 Ma). The oblique rifting fragmented the rift depression into segments separated by oblique-slip accommodation within reactivated Pan-African (ca. 600 Ma) fracture zones, resulting in the development of antithetic faults and an en-echelon distribution of inland ESB. The current phase of rifting was instigated by the development of the Dead Sea Transform in response to increased northeasterly extension during the middle Miocene (ca. 18 Ma). The model explains the widening of the Red Sea rift during the last phase more than the Gulf of Suez rift by developing more antithetic faults and formation of offshore ESB, and deepening the rift depression. 展开更多
关键词 Remote Sensing TECTONIC model marginal Sub-Basins RIFT ZONE Red SEA
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Gravity Modeling for the Rifted Crust at the Arabian Shield Margin – Further Insight into Red Sea Spreading
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作者 Saad Mogren Manoj Mukhopadhyay 《Open Journal of Geology》 2013年第2期28-33,共6页
A large variation in elevation and gravity anomaly prevails from the Red Sea coast to the interior of the Arabian Shield (AS) across the Asir Igneous Province (AIP);The Asir Mountain (AM) is developed on AIP. Here the... A large variation in elevation and gravity anomaly prevails from the Red Sea coast to the interior of the Arabian Shield (AS) across the Asir Igneous Province (AIP);The Asir Mountain (AM) is developed on AIP. Here the elevation varies from 45 - 2700 m, corresponding changes in F.A. are from –30 to + 220 mgal and B.A. from +22 to –175 mgal. Regression relationships between elevation and gravity anomalies demonstrate significant changes in trend at about 400 m threshold of elevation across the pediment west of AM, at about 45 km inland of the shoreline, flanking the Hizaz-Asir Escarpment (HAE). Gravity anomaly variation along a traverse taken across HAE and AIP is interpreted here in terms of anomalous masses in crust as well as due to deeper crustal configuration. 2D gravity interpretation is, in part, constrained by surface geology, available geologic cross-sections for crust, interpretations from the IRIS Deep-Seismic Refraction Line, and to a lesser extent by the available gross results from shear-wave splitting and receiver function analysis. The gravity model provides probable solutions for the first time on geometric configuration and geophysical identification: a) for the seaward margin of the mid-Tertiary Mafic Crust (TMC) below sediment cover of the Asir pediment that coincides with the 400 m threshold elevation. This signifies an anomalous uplift at the rifting phase. Moho below TMC extends from 10 - 22 km depth across HAE and west margin of AIP, b). Thinned continental crust below the Asir margin whose upper layer coincides with a seismic reflector is at about 22 km depth, c). Rift-margin characteristic detachment fault associated with basaltic flows on top surface of TMC at its inner margin, d). Two geologically mapped low-angle normal faults dipping to the east developed between the basic rocks intruding the AIP and e). felsic pluton farther east within AS. Large scale igneous activity followed by intense deformation affecting AIP clearly owes their origin to the rifting architecture of the AS at the Red Sea extensional margin. 展开更多
关键词 Shield-margin MAFIC CRUST Asir IGNEOUS Province Seismic MOHO 2D Gravity CRUSTAL model Red Sea Ex-tensional margin
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Recent Trends in Satellite-Derived Chlorophyll and Aerosol Optical Depth Together with Simulated Dimethylsulfide in the Eastern China Marginal Seas
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作者 QU Bo GABRIC Albert J. 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第2期486-498,共13页
The biogenic compound dimethylsulfide(DMS)produced by a range of marine biota is the major natural source of re-duced sulfur to the atmosphere and plays a major role in the formation and evolution of aerosols,potentia... The biogenic compound dimethylsulfide(DMS)produced by a range of marine biota is the major natural source of re-duced sulfur to the atmosphere and plays a major role in the formation and evolution of aerosols,potentially affecting climate.The spatio-temporal distribution of satellite-derived chlorophyll_a(CHL)and aerosol optical depth(AOD)for the recent years(2011-2019)in the Eastern China Marginal Seas(ECMS)(25°-40°N,120°-130°E)are studied.The seasonal CHL peaks occurred during late April and the CHL distribution displays a clear zonal gradient.Elevated CHL was also observed along the northern and western coastlines during summer and winter seasons.Trend analysis shows that mean CHL decreases by about 10%over the 9-year study period,while AOD was higher in south and lower in north during summertime.A genetic algorithm technique is used to calibrate the key model parameters and simulations are carried out for 2015,a year when field data was available.Our simulation results show that DMS seawater concentration ranges from 1.56 to 5.88 nmol L^(−1) with a mean value of 2.76 nmol L^(−1).DMS sea-air flux ranges from 2.66 to 5.00mmol m^(−2) d^(−1) with mean of 3.80mmol m^(−2) d^(−1).Positive correlations of about 0.5 between CHL and AOD were found in the study region,with higher correlations along the coasts of Jiangsu and Zhejiang Provinces.The elevated CHL concentration along the west coast is correlated with increased sea-water concentrations of DMS in the region.Our results suggest a possible influ-ence of DMS-derived aerosol in the local ECMS atmosphere,especially along the western coastline of ECMS. 展开更多
关键词 dimethylsulfide sea-to-air flux CHLOROPHYLL-A aerosol optical depth biogeochemical model Eastern China marginal Seas
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Diagnostic value of preoperative examination for evaluating margin status in breast cancer
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作者 Peng Liu Ye Zhao +4 位作者 Dong-Dong Rong Kai-Fu Li Ya-Jun Wang Jing Zhao Hua Kang 《World Journal of Clinical Cases》 SCIE 2023年第20期4852-4864,共13页
BACKGROUND A positive resection margin is a major risk factor for local breast cancer recurrence after breast-conserving surgery(BCS).Preoperative imaging examinations are frequently employed to assess the surgical ma... BACKGROUND A positive resection margin is a major risk factor for local breast cancer recurrence after breast-conserving surgery(BCS).Preoperative imaging examinations are frequently employed to assess the surgical margin.AIM To investigate the role and value of preoperative imaging examinations[magnetic resonance imaging(MRI),molybdenum target,and ultrasound]in evaluating margins for BCS.METHODS A retrospective study was conducted on 323 breast cancer patients who met the criteria for BCS and consented to the procedure from January 2014 to July 2021.The study gathered preoperative imaging data(MRI,ultrasound,and molybdenum target examination)and intraoperative and postoperative pathological information.Based on their BCS outcomes,patients were categorized into positive and negative margin groups.Subsequently,the patients were randomly split into a training set(226 patients,approximately 70%)and a validation set(97 patients,approximately 30%).The imaging and pathological information was analyzed and summarized using R software.Non-conditional logistic regression and LASSO regression were conducted in the validation set to identify factors that might influence the failure of BCS.A column chart was generated and applied to the validation set to examine the relationship between pathological margin range and prognosis.This study aims to identify the risk factors associated with failure in BCS.RESULTS The multivariate non-conditional logistic regression analysis demonstrated that various factors raise the risk of positive margins following BCS.These factors comprise non-mass enhancement(NME)on dynamic contrastenhanced MRI,multiple focal vascular signs around the lesion on MRI,tumor size exceeding 2 cm,type III timesignal intensity curve,indistinct margins on molybdenum target examination,unclear margins on ultrasound examination,and estrogen receptor(ER)positivity in immunohistochemistry.LASSO regression was additionally employed in this study to identify four predictive factors for the model:ER,molybdenum target tumor type(MT Xmd Shape),maximum intensity projection imaging feature,and lesion type on MRI.The model constructed with these predictive factors exhibited strong consistency with the real-world scenario in both the training set and validation set.Particularly,the outcomes of the column chart model accurately predicted the likelihood of positive margins in BCS.CONCLUSION The proposed column chart model effectively predicts the success of BCS for breast cancer.The model utilizes preoperative ultrasound,molybdenum target,MRI,and core needle biopsy pathology evaluation results,all of which align with the real-world scenario.Hence,our model can offer dependable guidance for clinical decisionmaking concerning BCS. 展开更多
关键词 Breast cancer Breast-conserving surgery Imaging features Positive surgical margin Regression analysis model
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恒定市场份额三层次两极均化模型及其应用——我国对“一带一路”沿线国家农产品出口增长的驱动因素及其贡献率分析 被引量:2
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作者 葛明 贾怀勤 赵素萍 《统计研究》 CSSCI 北大核心 2024年第2期3-14,共12页
恒定市场份额(CMS)三层次两极均化模型将微观层面的商品价格、数量、种类,中观层面的国别、产业结构,与宏观层面的市场份额和需求规模有机结合起来,系统刻画出口波动的直接因素。基于该模型,本文从总体、动态、区域、产业4个维度逐层解... 恒定市场份额(CMS)三层次两极均化模型将微观层面的商品价格、数量、种类,中观层面的国别、产业结构,与宏观层面的市场份额和需求规模有机结合起来,系统刻画出口波动的直接因素。基于该模型,本文从总体、动态、区域、产业4个维度逐层解析2002—2021年我国对“一带一路”沿线国家农产品出口增长的驱动因素及其贡献率。结果表明,进口需求效应占据主导地位,需求数量和价格水平增长均有显著贡献,虽然出口竞争力效应总体表现不佳,但是品类竞争力和质量竞争力均小幅改善。“一带一路”倡议提出后,出口竞争力效应显著增长,特别是数量竞争力效应大幅改善。研究还表明,上述效应在不同产业和区域既存在共性特征,也具有一定程度差异性。相对于CMS两层次分解框架,CMS三层次两极均化模型的研究内容更加丰富,经济学含义更加清晰,政策启示更加明确,具有更广泛的应用价值。 展开更多
关键词 CMS模型 三元边际 国际竞争力 “一带一路”倡议 农产品
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Fixed-Bed Column Adsorption Modeling of MnO4- Ions from Acidic Aqueous Solutions on Activated Carbons Prepared with the Biomass
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作者 Charly Mve Mfoumou Francis Ngoye +3 位作者 Pradel Tonda-Mikiela Mbouiti Lionel Berthy Bouassa Mougnala Spenseur Guy Raymond Feuya Tchouya 《Open Journal of Inorganic Chemistry》 CAS 2023年第2期25-42,共18页
Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-<... Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-</sup> ions in acidic media on fixed bed column and on the kinetic modeling of experimental data of breakthrough curves of  MnO<sub>4</sub>-</sup> ions obtained. Results on the adsorption of MnO<sub>4</sub>-</sup>  ions in fixed-bed dynamics obtained on AC-400 and AC-600 adsorbents beds indicated that the AC-400 bed appears to be the most efficient in removing MnO<sub>4</sub>-</sup>  ions in acidic media. Indeed, the adsorbed amounts, the adsorbed capacities at saturation and the elimination percentage of MnO<sub>4</sub>-</sup>  ions obtained with AC-400 (31.24 mg;52.06 mg·g<sup>-1</sup> and 41.65% respectively) were higher compared to those obtained with AC-600 (9.87 mg;16.45 mg·g<sup>-1</sup> and 17.79% respectively). The breakthrough curves kinetic modeling revealed that the Thomas model and the pseudo-first-order kinetic model were the most suitable models to describe the adsorption of MnO<sub>4</sub>-</sup>  ions on adsorbents studied in our experimental conditions. The results of the intraparticle diffusion model showed that intraparticle diffusion was involved in the adsorption mechanism of MnO<sub>4</sub>-</sup>  ions on investigated adsorbents and was not the limiting step and the only process controlling MnO<sub>4</sub>-</sup>  ions adsorption. In contrast to AC-400, the intraparticle diffusion on AC-600 bed plays an important role in the adsorption mechanism of MnO<sub>4</sub>-</sup>  ions. 展开更多
关键词 Acidic Media MnO4 style=margin-left:-6px >- BIOMASS Activated Carbon Dynamic Adsorption Kinetics models
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