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Obtaining 2D Soil Geotechnical Profiles from Cokriging Interpolation of Sample Data and Electrical Resistivity Tomography (ERT)—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Noel Howley +11 位作者 Andy Legg Tristan Pryer Danielle Silva de Paula Tatiana Sussel Gonçalves Mendes Daniel Metodiev Marcio Roberto Magalhães de Andrade Silvio Jorge Coelho Simões Maiconn Vinicius de Moraes Marcio Augusto Ernesto de Moraes Luana Albertani Pampuch Rodolfo Moreda Mendes Harideva Marturano Egas 《International Journal of Geosciences》 CAS 2024年第7期525-548,共24页
Brazil annually faces significant challenges with mass movements, particularly in areas with poorly constructed housing, inadequate engineering, and lacking sanitation infrastructure. Campos do Jordão, in Sã... Brazil annually faces significant challenges with mass movements, particularly in areas with poorly constructed housing, inadequate engineering, and lacking sanitation infrastructure. Campos do Jordão, in São Paulo state, is a city currently grappling with these issues. This paper details a study conducted within a pilot area in Campos do Jordão, where geophysical surveys and geotechnical borehole data were integrated. The geophysical surveys provided 2D profiles, and samples were collected to analyse soil moisture and plasticity. These datasets were combined using a Cokriging-based model to produce an accurate representation of the subsurface conditions. The enhanced modelling of subsurface variability facilitates a deeper understanding of soil behavior, which can be used to improve landslide risk assessments. This approach is innovative, particularly within the international context where similar studies often do not address the complexities associated with urban planning deficits such as those observed in some areas of Brazil. These conditions, including the lack of proper sanitation and irregular housing, significantly influence the geological stability of the region, adding layers of complexity to subsurface assessments. Adapting geotechnical evaluation methods to local challenges offers the potential to increase the efficacy and relevance of geological risk management in regions with similar socio-economic and urban characteristics. 展开更多
关键词 Mass movements GEOPHYSICS ERT Geotechnical Surveys Campos do Jordão COKRIGING
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Is It about a Bicycle? A Posthumanist Perspective on the Role of Women’s Bicycles in WWII Resistance Movements
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作者 Zuzana Križalkovičová 《Sociology Study》 2024年第4期198-211,共14页
Drawing upon Donna Haraway’s cyborg theory,this paper argues that the bicycle can be conceived as a cyborg extension of body and identity which transcended its mechanical essence to become an integral co-partner for ... Drawing upon Donna Haraway’s cyborg theory,this paper argues that the bicycle can be conceived as a cyborg extension of body and identity which transcended its mechanical essence to become an integral co-partner for women involved in resistance activities in WWII.More specifically,the study explores how women used cycling during World War Ⅱ not only for mobility but as a profound expression of courage,endurance and solidarity which enabled them to overcome physical and symbolic barriers under totalitarian regimes.The bicycle emerges not only as a central co-agent but also actively co-creates the situations in which it emerges as a transformative force.Cycling acted as a catalyst for personal and collective empowerment,fostering new subjectivities while transcending physical and social limitations.This study sparks multidimensional discourse on how technological tools can co-create our societies and identities,offering insights into how bicycles can drive socio-political change,promote emancipation and foster inclusivity. 展开更多
关键词 BICYCLE female involvement in World WarⅡresistance movements cyborg theory
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Existence of Extracellular Calmodulin in the Lower Epidermis of the Leaves of Vicia faba and Its Role in Regulating Stomatal Movements
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作者 陈玉玲 张学琴 +1 位作者 陈珈 王学臣 《Acta Botanica Sinica》 CSCD 2003年第1期40-46,共7页
As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to ... As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to environmental stimuli. CaM was found to be extracellular both in guard cells of broad bean leaves and in epidermal cells by immuno-electron microscopy and immuno-fluorescence microscopy techniques. Exogenous purified CaM enhanced stomatal closure and inhibited stomatal opening with an optimal concentration of 10(-8) mol/L; CaM antagonist W7-agarose and anti-CaM serum, which were membrane-impermeable macromolecules, inhibited stomatal closure and promoted stomatal opening. All these data showed that endogenous extracellular CaM. of guard cells did promote stomatal closure and inhibit stomatal opening, and could he active only outside the cells. Therefore under natural conditions, the endogenous extracellular CaM of guard cells might regulate stomatal movements as a primary messenger together with other signal molecules, and might be an important linkage between environmental stimuli and cell responses. 展开更多
关键词 extracellular CaM Vicia faba stomatal movement
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Eye movements during inspecting pictures of natural scenes for information to verify sentences
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作者 陈庆荣 蒋志杰 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期444-447,共4页
As eye tracking can be used to record moment-to-moment changes of eye movements as people inspect pictures of natural scenes and comprehend information, this paper attempts to use eye-movement technology to investigat... As eye tracking can be used to record moment-to-moment changes of eye movements as people inspect pictures of natural scenes and comprehend information, this paper attempts to use eye-movement technology to investigate how the order of presentation and the characteristics of information affect the semantic mismatch effect in the picture-sentence paradigm. A 3(syntax)×2(semantic relation) factorial design is adopted, with syntax and semantic relations as within-participant variables. The experiment finds that the semantic mismatch is most likely to increase cognitive loads as people have to spend more time, including first-pass time, regression path duration, and total fixation duration. Double negation does not significantly increase the processing difficulty of pictures and information. Experimental results show that people can extract the special syntactic strategy from long-term memory to process pictures and sentences with different semantic relations. It enables readers to comprehend double negation as affirmation. These results demonstrate that the constituent comparison model may not be a general model regarding other languages. 展开更多
关键词 natural scene semantic mismatch double negation eye movement
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Far-field crustal movements before and after the 2011 Ms9.0 Japan earthquake from GPS observations 被引量:14
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作者 Gu Guohua Wang Wuxing 《Geodesy and Geodynamics》 2011年第3期1-7,共7页
The paper gives an analysis of the displacement time series before and after the March 11,2011 Ms9.0 east Japan earthquake and co-seismic displacements observed at continuous GPS stations in and around China. The resu... The paper gives an analysis of the displacement time series before and after the March 11,2011 Ms9.0 east Japan earthquake and co-seismic displacements observed at continuous GPS stations in and around China. The results showed a broad-scaled related elastic-rebound process and some premonitory horizontal crustal movements to this earthquake over this vast area. 展开更多
关键词 Japan earthquake crustal movement GPS earthquake prediction co-seismic displacement
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Using Quantile Regression Approach to Analyze Price Movements of Agricultural Products in China 被引量:7
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作者 LI Gan-qiong XU Shi-wei +2 位作者 LI Zhe-min SUN Yi-guo DONG Xiao-xia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第4期674-683,共10页
This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese market.We employ a linear quantile approach not only to explore potential data hete... This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese market.We employ a linear quantile approach not only to explore potential data heteroscedasticity but also to generate confidence bands for the purpose of price stability study.We then evaluate our models by comparing the prediction intervals generated from the quantile regression models with in-sample and out-of-sample forecasts.Using monthly data from January 2000 to October 2010,we observed these findings:(i) the price changes of cost factors asymmetrically and unequally influence those of the livestock across different quantiles;(ii) the performance of our models is robust and consistent for both in-sample and out-of-sample forecasts;(iii) the confidence intervals generated from 0.05th and 0.95th quantile regression models are good methods to forecast livestock price fluctuation. 展开更多
关键词 cost factors agricultural products forecasting price movements quantile regression model
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Eye Movements, Cognitive Processes, and Reading 被引量:6
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作者 Keith Rayner 《心理与行为研究》 2004年第3期482-488,共7页
关键词 eye movements perceptual SPAN INTEGRATION ACROSS SACCADES eye movement control.
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Anomalous crustal movements before great Wenchuan earthquake observed by GPS 被引量:10
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作者 Gu Guohua Meng Guojie Wang Wuxing 《Geodesy and Geodynamics》 2011年第2期13-22,共10页
Studies of GPS data carried out before and after the great Wenchuan earthquake of Ms8.0 on May 12, 2008 show that anomalous crustal movements occurred before the earthquake. Data from 4 pre-earthquake observation sess... Studies of GPS data carried out before and after the great Wenchuan earthquake of Ms8.0 on May 12, 2008 show that anomalous crustal movements occurred before the earthquake. Data from 4 pre-earthquake observation sessions at a dense network of stations show that there were prominent broad-ranged long- and midterm anomalies in horizontal displacements and strain and in vertical displacements. Data from the fewer-numbered reference stations of continuous GPS observations since 1999 in West and South China showed short-term preseismic anomalies in horizontal displacements. The detection of co-seismic horizontal displacements at these stations supports the existence of the pre-earthquake anomalies. Results of single-epoch solutions of data from continuous-observation stations near the epicenter also show large imminent anomalies in vertical displacements. Although the Wenchuan earthquake was not predicted, these results give a strong indication that GPS should be the main observation technique for long-term, mid-term, short-term and imminent earthquake predictions. 展开更多
关键词 Wenchuan earthquake earthquake prediction GPS crustal movement horizontal displace- ment vertical displacement
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Energy-optimal control model for train movements 被引量:3
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作者 李克平 高自友 毛保华 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期359-364,共6页
In this paper, we propose a new cellular automaton (CA) model for train movement simulations under mixed traffic conditions. A kind of control strategy is employed for trains to reduce energy consumption. In the pro... In this paper, we propose a new cellular automaton (CA) model for train movement simulations under mixed traffic conditions. A kind of control strategy is employed for trains to reduce energy consumption. In the proposed CA model, the driver controls the train movements by using some updated rules. In order to obtain a good insight into the evolution behaviours of the rail traffic flow, we investigate the space-time diagram of the rail traffic flow and the trajectories of the train movements. The numerical simulation results demonstrate that the proposed CA model can well describe the dynamic behaviours of the train movements. Some complex phenomena of train movements can be reproduced, such as the train delay propagations, etc. 展开更多
关键词 train movement cellular automaton moving-block
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Earth crust vertical movements according to ITRF2000, ITRF2005,ITRF2008 and ITRF2014 coordinate systems and their comparing analysis 被引量:3
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作者 N.A.Chujkova T.G.Maximova +1 位作者 T.S.Chesnokova A.N.Grushinsky 《Geodesy and Geodynamics》 2018年第2期109-114,共6页
The analysis of Earth’s crust movement vertical velocities was made both for separate regions, and averaged on regions. As input data coordinates and velocities of earth crust points, obtained in International Coordi... The analysis of Earth’s crust movement vertical velocities was made both for separate regions, and averaged on regions. As input data coordinates and velocities of earth crust points, obtained in International Coordinate Systems ITRF2000, ITRF2005,ITRF2008 on the base of processing radio interferometric(VLBI), laser(SLR), Doppler(DORIS) and GPS observations was used. For the purpose of global analysis all input velocity values were averaged in the x trapezoids. For filling trapezoids the spherical function expansion to N=36 was made. Expansion harmonic coefficients allowed determine the global characteristics of earth crust movements both for all Earth, and for separate hemispheres, polar and equatorial regions, continents and oceans. It appears, that polar regions were risen, and equatorial ones were lowered, that can indicate the modern Earth oblateness reduction. The constructed maps of vertical velocities were compared with obtained by us map of earth crust strain distribution. It is appeared, that regions of modern earth surface rising(Fennoscandia, Canada, Antarctica) coincide with regions of vertical extension strain, and the lowering regions-with compression regions. Simultaneously with the determination of harmonious coefficients the mean-square error of approximation for expansion of power n=1 N and power dispersion were determined. Whereas the results converge badly and dispersion increased with the n grows, hence we can concludes, that vertical movements do not characterized global earth crust movement and denotes the unrelated character of these movement. Seemingly, the main cause of such movement origin is the local seismic events(earthquake, volcanic eruption and so on). It confirms by our conclusions about correspondence of vertical strain maximal gradient(and therefore vertical velocities) map of the earthquake distribution. In work the detailed analysis of obtained results for separate Earth’s regions was made. 展开更多
关键词 Crust movement Coordinate system UPLIFT
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Mass movements in small canyons in the northeast of Baiyun deepwater area, north of the South China Sea 被引量:4
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作者 LI Xishuang LIU Lejun +3 位作者 LI Jiagang GAO Shan ZHOU Qingjie SU Tianyun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期35-42,共8页
The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass m... The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass movements in small submarine canyons in the northeast of Baiyun deepwater area, north of the South China Sea (SCS), and their strong effects on the evolution of the canyons based on geophysical data. Submarine canyons in the study area arrange closely below the shelf break zone which was at the depth of -500 m. Within submarine canyons, seabed surface was covered with amounts of failure scars resulted from past small-sized landslides. A complex process of mass transportation in the canyons is indicated by three directions of mass movements. Recent mass movement deposits in the canyons exhibit translucent reflections or parallel reflections which represent the brittle deformation and the plastic deformation, respectively. The area of most landslides in the canyons is less than 3 km2. The trigger mechanisms for mass movements in the study area are gravitational overloading, slope angle and weak properties of soil. Geophysical data indicate that the genesis of submarine canyons is the erosion of mass movements and consequent turbidity currents. The significant effects of mass movements on canyon are incision and sediment transportation at the erosion phases and fillings supply at the fill phases. This research will be helpful for the geological risk assessments and understanding the sediment transportation in the northern margin of the SCS. 展开更多
关键词 mass movement geophysical data trigger mechanism submarine canyon north of the South China Sea
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Modeling and simulation of high-speed passenger train movements in the rail line 被引量:3
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作者 曹成铉 许琰 李克平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期239-245,共7页
In this paper, we propose a new formula of the real-time minimum safety headway based on the relative velocity of consecutive trains and present a dynamic model of high-speed passenger train movements in the rail line... In this paper, we propose a new formula of the real-time minimum safety headway based on the relative velocity of consecutive trains and present a dynamic model of high-speed passenger train movements in the rail line based on the proposed formula of the minimum safety headway. Moreover, we provide the control strategies of the high-speed passenger train operations based on the proposed formula of the real-time minimum safety headway and the dynamic model of highspeed passenger train movements. The simulation results demonstrate that the proposed control strategies of the passenger train operations can greatly reduce the delay propagation in the high-speed rail line when a random delay occurs. 展开更多
关键词 SIMULATION dynamic model control strategies of train movements high-speed passenger train
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Observations of coastal aeolian dune movements at Feicuidao, on the Changli Gold Coast in Hebei Province 被引量:3
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作者 YuXiang Dong DeQuan Huang JianHui Du 《Research in Cold and Arid Regions》 CSCD 2013年第3期324-330,共7页
High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei... High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei Province in 2006-2008. Our data provide information on the direction, type, and velocity of coastal dune movements, and indicate that the coastal dunes in this re- gion are characterized as slow and landward advancing, with to-and-fro fluctuations. The bottom of the studied coastal transverse ridge was stable during the observation period but the position of its crest advanced eastward (seaward) during summer and au- tumn, and moved landward (westward) in winter and spring. Thus, its crest moved generally landward (westward) but fluctuated to-and-fro eastward and westward. In contrast, the entire coastal crescent dune advanced landward (westward) in a to-and-fro manner, and the velocity of its movement was faster than that of the transverse ridge dune. These results are mainly related to the wind conditions in the research area, the height and volume of the two types of coastal dunes. 展开更多
关键词 coastal dune movement observation Changli in Hebei Province
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Comprehensive Investigation of Submarine Slide Zones and Mass Movements at the Northern Continental Slope of South China Sea 被引量:1
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作者 CHEN Hongjun LIANG Jin GONG Yuehua 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第1期101-117,共17页
Multi-beam bathymetry and seismic sequence surveys in the northern slope of the South China Sea reveal detailed geomorphology and seismic stratigraphy characteristics of canyons, gullies, and mass movements. Modern ca... Multi-beam bathymetry and seismic sequence surveys in the northern slope of the South China Sea reveal detailed geomorphology and seismic stratigraphy characteristics of canyons, gullies, and mass movements. Modern canyons and gullies are roughly elongated NNW–SSW with U-shaped cross sections at water depths of 400–1000 m. Mass movements include slide complexes, slide scars, and debris/turbidity flows. Slide complexes and slide scars are oriented in the NE–SW direction and cover an area of about 1790 and 926 km^2, respectively. The debris/turbidity flows developed along the lower slope. A detailed facies analysis suggests that four seismic facies exist, and the late Cenozoic stratigraphy above the acoustic basement can be roughly subdivided into three sequences separated by regional unconformities in the study area. The occurrence of gas hydrates is marked by seismic velocity anomalies, bottom-simulating reflectors, gas chimneys, and pockmarks in the study area. Seismic observations suggest that modern canyons and mass movements formed around the transition between the last glacial period and the current interglacial period. The possible existence and dissociation of gas hydrates and the regional tectonic setting may trigger instability and mass movements on the seafloor. Canyons may be the final result of gas hydrate dissociation. Our study aims to contribute new information that is applicable to engineering construction required for deep-water petroleum exploration and gas hydrate surveys along any marginal sea. 展开更多
关键词 SOUTH China Sea SUBMARINE SLIDE ZONES mass movements CONTINENTAL slope
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Graphene stirrer with designed movements:Targeting on environmental remediation and supercapacitor applications 被引量:2
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作者 Yang Huang Wei Chen +8 位作者 Hongfei Li Minshen Zhu Fuwei Liu Qi Xue Zengxia Pei Zifeng Wang Lei Wang Yan Huang Chunyi Zhi 《Green Energy & Environment》 SCIE 2018年第1期86-96,共11页
Beyond the traditional focus on improvements in mechanical, electronic and absorption properties, controllability, actuation, and dynamic response of monoliths have received increasing attentions for practical applica... Beyond the traditional focus on improvements in mechanical, electronic and absorption properties, controllability, actuation, and dynamic response of monoliths have received increasing attentions for practical applications. However, most of them could only realize simple response to constant conditions(e.g. a stationary magnetic field) while carrying out humdrum motions. By controlling distribution of metal organic framework obtained carbon-enriched Fe304 nanoparticles in self-assembly reduced graphene oxide(RGO) monoliths, we could achieve two distinctive RGO-Fe_3 O_4 stirrers that could dynamically respond to the rapidly changing magnetic field while executing designed movements precisely: rotating with lying down posture or standing straight posture. These stirrers can not only be applied in environmental remediation(e.g.suction skimmer), but also be recycled as electrode active materials for supercapacitors after fulfilling their destiny, realizing transformation of trash to treasure, which will inspire other dynamically responsive monoliths for various applications. 展开更多
关键词 Desinged movements Reduced graphene oxide Metal-organic framework FE3O4 STIRRER
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Measurement and analysis of associated mimic muscle movements 被引量:1
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作者 Guodong Feng Yuan Zhuang Zhiqiang Gao 《Journal of Otology》 CSCD 2015年第1期39-45,共7页
Objective: To measure movements of markers over the primary site and associated mimic muscles in certain facial expressions, for evaluating facial paresis and synkinesis. Methods: Participants included 22 normal subje... Objective: To measure movements of markers over the primary site and associated mimic muscles in certain facial expressions, for evaluating facial paresis and synkinesis. Methods: Participants included 22 normal subjects aged 45e66 years. Maximum shift(Smax) and velocity(Vmax)were measured using a custom-designed 3-D dynamic quantitative analysis system of facial motion(3-D ASFM) based on motion capture technology. Measures were taken from peri-oral muscles during forceful brow raising and tight eye closure, and from muscles around the eye during grinning, right/left/bilateral mouth corner raising and smiling. Results: 1) During forceful brow raising, Smaxwas 3.65e4.46 mm for markers over perioral muscles, with the marker over the nasolabial fold showing a Vmaxgreater than others(60.60 mm/s on left and 62.70 mm/s on right). 2) In tight eye closure, Smaxof perioral muscle markers was 1.58e1.92 mm, with Vmaxbeing 11.40e14.76 mm/s. 3) In grinning, the largest eye muscle marker Smaxwas seen at the lower lid(3.93 mm on left and 4.15 mm on right) and the smallest at the inner canthus(1.59 mm on left and 1.53 mm on right), with the largest Vmaxseen at the upper lid and smallest also at the inner canthus(11.71 mm/s on left and11.09 mm/s on right). 4) In smiling, the largest non-oral Smaxand Vmaxwere seen at the upper lid(3.05 mm and 36.14 mm/s on left and 2.53 mm and 28.90 mm/s on right) and the smallest also at the inner canthus(0.69 mm and 7.22 mm/s on left and 0.77 mm and 7.80 mm/s on right). 5) In right mouth corner raising, Smaxand Vmaxat lateral and medial canthus and at lower lid were greater on right than left, while those at upper lid and brow were slightly greater on left than right. 6) In left mouth corner raising, Smaxand Vmaxat lateral canthus and upper and lower lids were greater on left than right. Conclusions: There are no absolute immobile points on the face when making facial expressions. In addition to the primary movement site, there are associated movements at other points on the face with consistent Smaxand Vmax.In assessing facial paresis and synkinesis, physiological associated facial movements should be taken into consideration. 展开更多
关键词 Facial expression Associated movement 3-Dimensiona
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Influence of breathing movements and Valsalva maneuver on vena caval dynamics 被引量:1
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作者 Alicia Laborda Sergio Sierre +4 位作者 Mauro Malvè Ignacio De Blas Ignatios Ioakeim William T Kuo Miguel Angel De Gregorio 《World Journal of Radiology》 CAS 2014年第10期833-839,共7页
AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 year... AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 years of age who required an abdominal computed tomography(CT) and central venous access. IVC cross-sectional areas were measured on CT scans at three levels, suprarenal(SR), juxtarenal(JR) and infrarenal(IR), during neutral breathing and again during the Valsalva maneuver. All patientswere instructed on how to perform a correct Valsalva maneuver. In order to reduce the total radiation dose in our patients, low-dose CT protocols were used in all patients. The venous blood pressure(systolic, diastolic and mean) was invasively measured at the same three levels with neutral breathing and the Valsalva maneuver during venous port implantation. From CT scans, threedimensional models of the IVC were constructed and a collapsibility index was calculated for each patient. These data were then correlated with venous pressures and cross-sectional areas.RESULTS: The mean patient age was 51.64 ± 12.01 years. The areas of the ellipse in neutral breathing were 394.49 ± 85.83(SR), 380.10 ± 74.55(JR), and 342.72 ± 49.77 mm2(IR), and 87.46 ± 18.35(SR), 92.64 ± 15.36(JR) and 70.05 ± 9.64 mm2(IR) during the Valsalva(P s < 0.001). There was a correlation between areas in neutral breathing and in the Valsalva maneuver(P < 0.05 in all areas). Large areas decreased more than smaller areas. The collapsibility indices were 0.49 ± 0.06(SR), 0.50 ± 0.04(JR) and 0.50 ± 0.04(IR), with no significant differences in any region. Reconstructed three-dimensional models showed a flattening of the IVC during Valsalva, adopting an ellipsoid cross-sectional shape. The mean pressures with neutral breathing were 9.44 ± 1.78(SR), 9.40 ± 1.44(JR) and 8.84 ± 1.03 mmHg(IR), and 81.08 ± 21.82(SR), 79.88 ± 19.01(JR) and 74.04 ± 16.56 mmHg(IR) during Valsalva(P s < 0.001). There was a negative correlation between cross-sectional caval area and venous blood pressure, but this was not statistically significant in any of the cases. There was a significant correlation between diastolic and mean pressures measured during neutral breathing and in Valsalva.CONCLUSION: Respiratory movements have a major influence on IVC dynamics. The increase in intracaval pressure during Valsalva results in a significant de-crease in the IVC cross-sectional area. 展开更多
关键词 INFERIOR vena cava Morphology RESPIRATORY movements Size VALSALVA VENOUS HEMODYNAMICS
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WATER AND SALT MOVEMENTS IN SIMULTANEOUS FLOOD-IRRIGATION AND WELL-DRAINAGE OPERATIONS 被引量:1
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作者 戚隆溪 邱克俭 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1996年第2期135-143,共9页
This paper describes a new technology for solonchak soil reclamation in which surface flood irrigation of fresh water and pumped wells drainage of salty groundwater are combined. The comprehensive investigation of wat... This paper describes a new technology for solonchak soil reclamation in which surface flood irrigation of fresh water and pumped wells drainage of salty groundwater are combined. The comprehensive investigation of water and salt movement has been conducted through field test, laboratory simulation and numerical calculation. The dependence of desalination on irrigation water quantity, drainage quantity, leaching time and other parameters is obtained based on the field tests. The entire desalination process under the flood-irrigation and well-drainage operations was experimentally simulated in a vertical soil column. The water and salt movement has been numerically analysed for both the field and laboratory conditions. The present work indicates that this new technology can greatly improve the effects of desalination. 展开更多
关键词 water and salt movements solonchak soil reclamation irrigation-drainage method
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Numerical Simulation of Waves Generated by Seafloor Movements 被引量:1
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作者 何海伦 宋金宝 +1 位作者 李爽 杨建平 《China Ocean Engineering》 SCIE EI 2008年第4期693-704,共12页
Waves generated by vertical seafloor movements are simulated by use of a fully nonlinear two-dimensional numerical wave tank. In the souree region, the seafloor lifts to a designated height by a generation function. T... Waves generated by vertical seafloor movements are simulated by use of a fully nonlinear two-dimensional numerical wave tank. In the souree region, the seafloor lifts to a designated height by a generation function. The numerical tests show that the linear theory is only valid for estimating the wave behaviors induced by the seafloor movements with a small amplitude, and the fully nonlinear numerical model should be adopted in the simulation of the wave generation by the large amplitude seafloor movements. Without the background surface waves, many numerical tests on the stable maximum elevations η0^max are carried out by beth the linear theory and the fully nonlinear model. The results of two models are compared and analyzed. For the fully nonlinear model, the influences of the amplitudes and the horizontal lengths on η^max are stronger than that of the characteristic duration times. Furthermore, results reveal that there are significant differences be- tween the linear theory and the fully nonlinear model. When the influences of the background surface waves are considered, the corresponding numerical analyses reveal that with the fully nonlinear model the η0^max near-linearly varies with the wave amplitudes of the surface waves, and the η0^max has significant dependences on the wave lengths and the wave phases of the surface waves. In addition, the differences between the linear theory and the fully nonlinear model are still obvious, and these differences are significantly affected by the wave parameters of the background surface waves, such as the wave amplitude, the wave length and the wave phase. 展开更多
关键词 boundary element method numerical wave tank seafloor movement surface waves
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A novel three-dimensional electric ophthalmotrope for improving the teaching of ocular movements 被引量:1
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作者 Lei Xiong Xiao-Yan Ding +5 位作者 Ya-Zhi Fan Yao Xing Xiao-Hui Zhang Ting Li Jian-Ming Wang Feng Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第12期1893-1897,共5页
AIM: To develop a novel three-dimensional(3D) electric ophthalmotrope to improve the ophthalmology teaching effectiveness and evaluate the teaching value. METHODS: A 3D electric ophthalmotrope was designed by simulati... AIM: To develop a novel three-dimensional(3D) electric ophthalmotrope to improve the ophthalmology teaching effectiveness and evaluate the teaching value. METHODS: A 3D electric ophthalmotrope was designed by simulating the movement of the ocular and the extraocular muscles according to Sherrington’s law. The model with joint bearing was to ensure the flexibility and centripetal rotation of the simulated ball and stepper motor as the driving device. A programmable processor was used to control the motion amplitude of the stepper motor. The size of hole was set at the back of the simulated shell to limit the amount of eye movement. Afterwards, using a 5-point Likert scale, 7 experts evaluated the 3D electric ophthalmotrope’s simulation ability and precision, compared with the traditional anatomical model. In addition, the teaching effectiveness of the 3D electric ophthalmotrope was evaluated at in-class quiz and final exam in a randomized controlled trial. RESULTS: The 3D electric ophthalmotrope could be operated easily to demonstrate the eye movements with motion of different ocular muscles. The experts agreed that the 3D electric ophthalmotrope was different from the traditional model and was easier for students to understand every extraocular muscles’ movement in each evaluation index(P<0.05). Moreover, the results of teaching effectiveness showed that the 3D electric ophthalmotrope were significantly greater than the traditional model both at in-class quiz(P<0.01) and final exam(P<0.05). CONCLUSION: This novel 3D electric ophthalmotrope is better than the traditional model, which can be to improve the ophthalmology teaching effectiveness for students to understand the extraocular muscles’ movement. 展开更多
关键词 extraocular muscles movement ocular myopathy medical education ophthalmotrope three-dimensional electric model
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