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Impact of temperature and precipitation lapse rate on hydrological modelling over Himalayan Gandak River Basin
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作者 Brijesh KUMAR Dipankar ROY Venkataraman LAKSHMI 《Journal of Mountain Science》 SCIE CSCD 2022年第12期3487-3502,共16页
The hydrology of Himalayan region is influenced by temperature lapse rate(TLAPS)and precipitation lapse rate(PLAPS).Therefore,hydrological modeling considering TLAPS and PLAPS is crucial to manage the water resources ... The hydrology of Himalayan region is influenced by temperature lapse rate(TLAPS)and precipitation lapse rate(PLAPS).Therefore,hydrological modeling considering TLAPS and PLAPS is crucial to manage the water resources in these terrains.In this research,Himalayan Gandak River basin is considered as the study area where TLAPS and PLAPS vary significantly due to high altitude of Himalayas.To assess the impact of TLAPS and PLAPS on water balance components,Soil Water Assessment Tool(SWAT)model was calibrated(2000-2007)and validated(2008-2014)on daily time step for three projects i.e.,Reference Project(RP),Snowmelt Project(SP)and distributed elevation band snowmelt project(SWAT-ETISM).The analysis discloses that SWAT-ETISM model(which has TLAPS and PLAPS parameters)outperforms the RP and the SP models in predicting streamflow with improved statistical indicators R2=0.88,NSE=0.84 and PBIAS=11.9.Furthermore,it was observed that SWAT-ETISM model comprehensively improved the streamflow statistics by improving the snow water equivalent and water balance components through the consideration of TLAPS and PLAPS values for the region.Hence,the proposed SWAT-ETISM model can be used for estimation of the water budget at the high-altitude and data scarce alpine Himalayan regions and worldwide,where PLAPS and TLAPS are substantial due to altitudinal variation. 展开更多
关键词 Streamflow SWAT-ETISM Himalayan Regions Water balance Temperature lapse rate Precipitation lapse rate
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Time-lapse geophysical technology-based study on overburden strata changes induced by modern coal mining 被引量:16
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作者 Wenfeng Du Suping Peng +1 位作者 Guowei Zhu Feng Yang 《International Journal of Coal Science & Technology》 EI CAS 2014年第2期184-191,共8页
To study the impact of modern coal mining on overlying strata and its water bearing conditions,integrated time-lapse geophysical prospecting integrating 3D seismic,electrical and ground penetrating radar method were u... To study the impact of modern coal mining on overlying strata and its water bearing conditions,integrated time-lapse geophysical prospecting integrating 3D seismic,electrical and ground penetrating radar method were used.Through observing and analyzing the geophysical data variations of all stages of pre-mining,mining and post-mining as well as post-mining deposition stable period,impacts of coal mining on stratigraphic structure and its water bearing were studied and modern coal mining induced stratigraphic change pattern was summarized.The research result shows that the stratigraphic structure and the water bearing of surface layer during modern coal mining have self-healing pattern with mining time;the self-healing capability of near-surface strata is relatively strong while the roof weak;water bearing selfhealing of near-surface strata is relatively high while the roof strata adjacent to mined coal beds low.Due to integrated time-lapse geophysical prospecting technology has extra time dimension which makes up the deficiency of static analysis of conventional geophysical methods,it can better highlight the dynamic changes of modern coal mining induced overburden strata and its water bearing conditions. 展开更多
关键词 Time lapse Geophysical prospecting Coal mining Overburden strata Strata changes Modern coalmining
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Surface warming patterns dominate the uncertainty in global water vapor plus lapse rate feedback 被引量:1
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作者 Jingchun Zhang Jian Ma +2 位作者 Jing Che Zhenqiang Zhou Guoping Gao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第3期81-89,共9页
Climate feedbacks have been usually estimated using changes in radiative effects associated with increased global-mean surface temperature. Feedback uncertainties, however, are not only functions of global-mean surfac... Climate feedbacks have been usually estimated using changes in radiative effects associated with increased global-mean surface temperature. Feedback uncertainties, however, are not only functions of global-mean surface temperature increase. In projections by global climate models, it has been demonstrated that the geographical variation of sea surface temperature change brings significant uncertainties into atmospheric circulation and precipitation responses at regional scales. Here we show that the spatial pattern of surface warming is a major contributor to uncertainty in the combined water vapour-lapse rate feedback. This is demonstrated by computing the global-mean radiative effects of changes in air temperature and relative humidity simulated by 31 climate models using a methodology based on radiative kernels. Our results highlight the important contribution of regional climate change to the uncertainty in climate feedbacks, and identify the regions of the world where constraining surface warming patterns would be most effective for higher skill of climate projections. 展开更多
关键词 surface WARMING PATTERNS UNCERTAINTY water vapor FEEDBACK lapse RATE FEEDBACK relative humidity air temperature radiative kernels
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Analysis of Lower Tropospheric Lapse Rate Trend over Port Harcourt Coastal City, Nigeria 被引量:1
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作者 Vincent E. Weli David O. Edokpa 《Atmospheric and Climate Sciences》 2018年第2期134-142,共9页
Understanding the spatial distribution of temperature, especially the relationship between temperature and altitude, is essential for understanding both climatological and hydrological processes and their variabilitie... Understanding the spatial distribution of temperature, especially the relationship between temperature and altitude, is essential for understanding both climatological and hydrological processes and their variabilities. This is because those processes are sensitive to air temperature, especially in sub humid tropical regions, where air temperature influences the movements of pollutants and controls exchanges of energy and water fluxes between land and atmosphere particularly within the lower troposphere. This study examined the trend of lower tropospheric lapse rate in the coastal area of Port Harcourt, Nigeria. Six years’ data (2010-2015) for temperature between 1000 mbar and 850 mbar pressure levels was retrieved from era-interim re-analysis platform for the analysis. The data was acquired at 6-hourly synoptic hours: 0000H, 0600H, 1200H and 1800H at 0.125° grid resolution. Findings from the computed environmental lapse rate (ELR) show that conditional instability with an annual lapse rate of 5.5°C/km persists at the area from January to December. It was revealed that the months of December and January constituted the highest ELR trends of 6.5°C/km and 5.9°C/km respectively. This indicates that the month of December assumes a normal tropospheric lapse rate trend. The average range of lapse rate trend in the area which is close to the moist adiabatic lapse rate (MALR) of 5.0°C/km than the dry adiabatic lapse rate (DALR) shows that the study atmospheric environment is rich in water vapour. The 6-hourly synoptic analysis of the ELR pattern shows that lapse rate range between 1°C/km - 6.4°C/km and 6.5°C/km - 10°C/km dominates throughout the year at 0000 - 0600 Hrs and 1200 - 1800 Hrs respectively. This demonstrates a higher and lower lapse rate trend during the day and night periods respectively. Relating study findings to the potential of air to disperse emissions in the area suggests that air emissions will be conveyed through far and near distances across the boundary layers due to the moderate dispersive potential of air regarding the closeness of the average ELR to the MALR. Policies that will ensure that pollutants are dispersed aloft especially emission stacks above 50 m is advocated in the city of Port Harcourt. 展开更多
关键词 lapse Rates LOWER Troposphere PORT Harcourt Emissions
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Unraveling the distribution patterns of near-surface temperature lapse rates in the Northwestern Kunlun Mountains
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作者 SUN Cong-jian CHEN Wei SHEN Yan-jun 《Journal of Mountain Science》 SCIE CSCD 2022年第4期1168-1181,共14页
The near-surface temperature lapse rates for the core area of the Kunlun Mountains remain critically unresolved due to data scarcity.Here,we revealed the spatial and temporal patterns of nearsurface temperature lapse ... The near-surface temperature lapse rates for the core area of the Kunlun Mountains remain critically unresolved due to data scarcity.Here,we revealed the spatial and temporal patterns of nearsurface temperature lapse rate in the Kunlun Mountain regions based on both long-term meteorological records(1961-2017)and field surveys measured data(2012-2017).The results showed that(1)The near-surface temperature lapse rates(β;)has spatiotemporal distribution patterns on the Northwestern Kunlun Mountains(NWKM),and in complex terrain areas the complexity of the temperature-elevation relationship cannot be explained by the constant environmental temperature lapse rate(0.65℃/100 m)throughout alone.(2)Theβ;for the daily mean,minimum,and maximum temperature on the north slopes in the Kunlun mountain area are 0.41,0.47,and 0.37℃/100 m and on the Tiznafu River(TR)basin are 0.51,0.47 and 0.53℃/100 m,respectively.(3)The variations ofβ;for daily maximum and minimum temperature of the two regions exhibit similar monthly characteristics,which are lower in the winter and spring months than in other months.A greatest variability ofβ;for the daily mean,minimum,and maximum temperature appears in winter and a light variability ofβ;occurs in spring.The seasonal variability ofβ;for daily maximum temperature is greater than that for daily minimum temperature,and the seasonal variability ofβ;for daily average temperature has the smallest variability.(4)There is no significant trend of change occurred in theβ;of NWKM.(5)The spatial and temporal variations ofβ;for the NWKM are linked to the geographic differences and climate factors.The results of Grey Relational Analysis showed that theβ;distribution is mainly influenced by the wind speed and relative humidity of the NWKM. 展开更多
关键词 Near-surface Temperature lapse Rate Spatiotemporal Variations Controlling Factors Northwestern Kunlun Mountains
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Planetary Layer Lapse Rate Comparison of Tropical, Montane and Hot Semi-Arid Climates of Nigeria
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作者 David O.Edokpa Precious NEde 《Journal of Atmospheric Science Research》 2020年第2期11-18,共8页
This study assessed the pattern of planetary layer lapse rate across the major climate belts of Nigeria.Six years’data(2010-2015)for air temperature values between 1000 mbar and 850 mbar atmospheric pressure levels w... This study assessed the pattern of planetary layer lapse rate across the major climate belts of Nigeria.Six years’data(2010-2015)for air temperature values between 1000 mbar and 850 mbar atmospheric pressure levels was acquired from Era-Interim Re-analysis data centre.The data was retrieved at 6-hourly synoptic hours:00:00 Hr,06:00 Hr.at 0.125o grid resolution.Results showed that the lower tropospheric layers throughout the various climate belts has a positive lapse rate.Findings also revealed that the average annual lapse rate condition were:Tropical wet zone(Port Harcourt)-5.6 oC/km;Bi-modal Tropical continental zone(Enugu)-5.8 oC/km;Montane zone(Jos)-6.5 oC/km;Mono-modal Tropical continental zone(Kano)-6.6 oC/km;and Hot semi-arid zone(Maiduguri)-6.6 oC/km.This average values presents the lapse rates to be near the Saturated Adiabatic Lapse Rate(SALR).Average diurnal results for the climate belts showed that lapse rate is higher during the afternoon and transition periods than the rest periods and increases from the coastal areas northward.The seasonal periods of highest lapse rates during the day time are from December-May(i.e.-5.8-9.5 oC/km)with slight decrease from June-November.The positive lapse rates of range-1.8 to 5.9 oC/km observed during the period of dawn across the entire region showed that infrared radiation was still being released and modified by less energetic mechanical turbulence that characterizes the surface layer across Nigeria.This also indicate that global warming is real and in substantial effect.The study findings imply that conditional instability prevailed over the entire region,therefore,the planetary layer environment will be of slow to moderate dispersive potential and will require forceful mechanism to lift emissions introduced into it.It is recommended that industrial stacks should be above 50 m to enhance the dispersion of emissions aloft. 展开更多
关键词 lapse rates Planetary layer Climate belts Nigeria Emissions
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Using satellite-derived land surface temperatures to clarify the spatiotemporal warming trends of the Alborz Mountains in northern Iran
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作者 ROSHAN Gholamreza SARLI Reza +2 位作者 GHANGHERMEH Abdolazim TAHERIZADEH Mehrnoosh NIKNAM Arman 《Journal of Mountain Science》 SCIE CSCD 2024年第2期449-469,共21页
The Alborz Mountains are some of the highest in Iran,and they play an important role in controlling the climate of the country’s northern regions.The land surface temperature(LST)is an important variable that affects... The Alborz Mountains are some of the highest in Iran,and they play an important role in controlling the climate of the country’s northern regions.The land surface temperature(LST)is an important variable that affects the ecosystem of this area.This study investigated the spatiotemporal changes and trends of the nighttime LST in the western region of the Central Alborz Mountains at elevations of 1500-4000 m above sea level.MODIS data were extracted for the period of 2000-2021,and the Mann-Kendall nonparametric test was applied to evaluating the changes in the LST.The results indicated a significant increasing trend for the monthly average LST in May-August along the southern aspect.Both the northern and southern aspects showed decreasing trends for the monthly average LST in October,November,and March and an increasing trend in other months.At all elevations,the average decadal change in the monthly average LST was more severe along the southern aspect(0.60°C)than along the northern aspect(0.37°C).The LST difference between the northern and southern aspects decreased in the cold months but increased in the hot months.At the same elevation,the difference in the lapse rate between the northern and southern aspects was greater in the hot months than in the cold months.With increasing elevation,the lapse rate between the northern and southern aspects disappeared.Climate change was concluded to greatly decrease the difference in LST at different elevations for April-July. 展开更多
关键词 Global warming Mountainous areas lapse rate Surface air temperatures ALBORZ
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Loss to Specialized Cardiology Follow-Up in Adults Living with Congenital Heart Disease
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作者 Cheryl Dickson Danielle Osborn +3 位作者 David Baker Judith Fethney David S.Celermajer Rachael Cordina 《Congenital Heart Disease》 SCIE 2024年第1期49-63,共15页
Background:Much has been written about the loss to follow-up in the transition between pediatric and adult Congenital Heart Disease(CHD)care centers.Much less is understood about the loss to follow-up(LTF)after a succ... Background:Much has been written about the loss to follow-up in the transition between pediatric and adult Congenital Heart Disease(CHD)care centers.Much less is understood about the loss to follow-up(LTF)after a successful transition.This is critical too,as patients lost to specialised care are more likely to experience mor-bidity and premature mortality.Aims:To understand the prevalence and reasons for loss to follow-up(LTF)at a large Australian Adult Congenital Heart Disease(ACHD)centre.Methods:Patients with moderate or highly complex CHD and gaps in care of>3 years(defined as LTF)were identified from a comprehensive ACHD data-base.Structured telephone interviews examined current care and barriers to clinic attendance.Results:Overall,407(22%)of ACHD patients(n=1842)were LTF.The mean age at LTF was 31(SD 11.5)years and 54%were male;311(76%)were uncontactable.Compared to adults seen regularly,lost patients were younger,with a greater socio-economic disadvantage,and had less complex CHD(p<0.05 for all).We interviewed 59 patients(14%).The top 3 responses for care absences were“feeling well”(61%),losing track of time(36%),and not needing fol-low-up care(25%).Conclusions:A large proportion of the ACHD population becomes lost to specialised cardiac care,even after a successful transition.This Australian study reports younger age,moderate complexity defects,and socio-economic disadvantage as predictive of loss to follow-up.This study highlights the need for novel approaches to patient-centered service delivery even beyond the age of transition and resources to maintain patient engagement within the ACHD service. 展开更多
关键词 Loss to follow-up FOLLOW-UP adult congenital heart disease lapse in care gaps in care care gaps care continuity ACHD predictors
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STUDIES ON GEOGRAPHIC DISTRIBUTION OF THE ALTITUDINAL LAPSE RATE OF TEMPERATURE IN CHINA 被引量:3
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作者 方精云 《Chinese Science Bulletin》 SCIE EI CAS 1992年第23期1979-1983,共5页
Based on the statistical analysis, the author studied the geographic distribution of altitudinal lapse rate of temperature (ALRT) in China from points of the difference of the ALRT between the south and north, annual ... Based on the statistical analysis, the author studied the geographic distribution of altitudinal lapse rate of temperature (ALRT) in China from points of the difference of the ALRT between the south and north, annual change of the ALRT and effect of macrotopography on the ALRT, using temperature data from 671 national standard meteorological stations. 展开更多
关键词 altitudinal lapse RATE of TEMPERATURE (ALRT) distance from COAST (DC) LATITUDE macro-topography
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Media effects on the dynamics of a stochastic SIRI epidemic model with relapse and Lévy noise perturbation 被引量:4
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作者 Badr-Eddine Berrhazi Mohamed El Fatini +1 位作者 Roger Pettersson Aziz Laaribi 《International Journal of Biomathematics》 SCIE 2019年第3期227-247,共21页
In this paper, we study the dynamic properties of an SIRI epidemic model incorporating media coverage, and stochastically perturbed by a Lévy noise. We establish the existence of a unique global positive solution... In this paper, we study the dynamic properties of an SIRI epidemic model incorporating media coverage, and stochastically perturbed by a Lévy noise. We establish the existence of a unique global positive solution. We investigate the dynamic properties of the solution around both disease-free and endemic equilibria points of the deterministic model depending on the basic reproduction number under some noise excitation. Furthermore, we present some numerical simulations to support the theoretical results. 展开更多
关键词 DYNAMICS Lévy process white noisere lapse media COVERAGE
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Early detection and classification of live bacteria using time-lapse coherent imaging and deep learning 被引量:2
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作者 Hongda Wang Hatice Ceylan Koydemir +8 位作者 Yunzhe Qiu Bijie Bai Yibo Zhang Yiyin Jin Sabiha Tok Enis Cagatay Yilmaz Esin Gumustekin Yair Rivenson Aydogan Ozcan 《Light(Science & Applications)》 SCIE EI CAS CSCD 2020年第1期890-906,共17页
Early identification of pathogenic bacteria in food,water,and bodily fluids is very important and yet challenging,owing to sample complexities and large sample volumes that need to be rapidly screened.Existing screeni... Early identification of pathogenic bacteria in food,water,and bodily fluids is very important and yet challenging,owing to sample complexities and large sample volumes that need to be rapidly screened.Existing screening methods based on plate counting or molecular analysis present various tradeoffs with regard to the detection time,accuracy/sensitivity,cost,and sample preparation complexity.Here,we present a computational live bacteria detection system that periodically captures coherent microscopy images of bacterial growth inside a 60-mm-diameter agar plate and analyses these time-lapsed holograms using deep neural networks for the rapid detection of bacterial growth and the classification of the corresponding species.The performance of our system was demonstrated by the rapid detection of Escherichia coli and total coliform bacteria(i.e.,Klebsiella aerogenes and Klebsiella pneumoniae subsp.pneumoniae)in water samples,shortening the detection time by >12 h compared to the Environmental Protection Agency(EPA)-approved methods.Using the preincubation of samples in growth media,our system achieved a limit of detection(LOD)of ~1 colony forming unit(CFU)/L in≤9 h of total test time.This platform is highly cost-effective(~$0.6/test)and has high-throughput with a scanning speed of 24 cm2/min over the entire plate surface,making it highly suitable for integration with the existing methods currently used for bacteria detection on agar plates.Powered by deep learning,this automated and cost-effective live bacteria detection platform can be transformative for a wide range of applications in microbiology by significantly reducing the detection time and automating the identification of colonies without labelling or the need for an expert. 展开更多
关键词 COHERENT EARLY lapse
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BOUNDARY LAYER GROWTH AND LAPSE RATE CHANGES DETERMINED BY LIDAR AND SURFACE HEAT FLUX IN SOFIA
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作者 E.Donev K.Zeller +1 位作者 St.Panchev I.Kolev 《Acta meteorologica Sinica》 SCIE 1995年第1期101-111,共11页
In this study the results from a boundary layer experiment,conducted in autumn 1991 over a flat,build-up urban area in Southeast Sofia,together with some models for mixed layer growth rates are used to investigate the... In this study the results from a boundary layer experiment,conducted in autumn 1991 over a flat,build-up urban area in Southeast Sofia,together with some models for mixed layer growth rates are used to investigate the layered struc- ture of the vertical atmospheric stability distribution in the Sofia Valley.Lidar measurements of aerosol layer heights and morning boundary layer development are combined with surface eddy correlation measurements of kinematic heat and moisture fluxes,profiles of temperature and humidity,wind speed and wind direction.A diagnostic method is pres- ented for determining vertical lapse rates using surface meteorological measurements and lidar returns observed during the transition from nighttime stable stratification to daytime convective boundary layer after the sunrise. 展开更多
关键词 convective boundary layer LIDAR heat flux lapse rate
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Time-Lapse 3-D Seismic Wave Simulation via the Generalized Multiscale Finite Element Method
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作者 Yongchae Cho Richard L.Gibson,Jr. +2 位作者 Hyunmin Kim Mikhail Artemyev Yalchin Efendiev 《Communications in Computational Physics》 SCIE 2020年第6期401-423,共23页
Numerical solution of time-lapse seismic monitoring problems can be challenging due to the presence of finely layered reservoirs.Repetitive wave modeling using fine layered meshes also adds more computational cost.Con... Numerical solution of time-lapse seismic monitoring problems can be challenging due to the presence of finely layered reservoirs.Repetitive wave modeling using fine layered meshes also adds more computational cost.Conventional approaches such as finite difference and finite element methods may be prohibitively expensive if the whole domain is discretized with the cells corresponding to the grid in the reservoir subdomain.A common approach in this case is to use homogenization techniques to upscale properties of subsurface media and assign the background properties to coarser grid;however,inappropriate application of upscaling might result in a distortion of the model,which hinders accurate monitoring of the fluid change in subsurface.In this work,we instead investigate capabilities of a multiscale method that can deal with fine scale heterogeneities of the reservoir layer and more coarsely meshed rock properties in the surrounding domains in the same fashion.To address the 3-D wave problems,we also demonstrate how the multiscale wave modeling technique can detect the changes caused by fluid movement while the hydrocarbon production activity proceeds. 展开更多
关键词 Fluid simulation time lapse Generalized multiscale finite element elastic wave
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基于多源资料的一次弓状强飑线成熟结构研究
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作者 孙玉婷 李红莉 +3 位作者 汪小康 康兆萍 肖艳姣 林建 《气象科学》 北大核心 2023年第5期632-642,共11页
利用局地分析和预报系统(Local Analysis and Prediction System,LAPS),结合多源资料,分析了2018年3月4日暖区强飑线成熟阶段的热动力结构和大风形成机制。结果表明:暖区内层结不稳定范围向东扩展和强的垂直风切变,驱动飑线组织化加强... 利用局地分析和预报系统(Local Analysis and Prediction System,LAPS),结合多源资料,分析了2018年3月4日暖区强飑线成熟阶段的热动力结构和大风形成机制。结果表明:暖区内层结不稳定范围向东扩展和强的垂直风切变,驱动飑线组织化加强并向前移动和发展。成熟阶段飑线热动力结构呈现出两支强入流和冷池的典型特征,即前侧入流在低层(0~3.0 km)辐合上升,部分气流在高层翻转流向系统前侧,无后向流出;后侧中层(4.0~5.5 km)入流进入云体后部,在水凝物强烈相变降温作用下,密度增大转而下沉;下沉气流区降雨蒸发冷却增强了雷暴冷池。相比于飑线南段单一的对流线,北段弓形特点突出,后侧入流下降,加之存在尾随层状云,有更大的潜在冷却作用,促进气流加速下沉增强地面雷暴高压,最终导致更强的极端大风。 展开更多
关键词 飑线 入流 冷池 LAPS
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基于LAPS资料的一次江西连续性暴雨过程分析
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作者 吴菲菲 毕晨 《农业灾害研究》 2023年第3期104-106,共3页
利用LAPS资料,结合地面和高空常规观测资料、雷达资料,从环流背景、影响系统、物理量场等方面对2013年6月27—29日连续性暴雨过程进行分析,得出结论:(1)LAPS输出的产品时效性好,分辨率高,产品多样化,更好地丰富了对天气过程分析的方法,... 利用LAPS资料,结合地面和高空常规观测资料、雷达资料,从环流背景、影响系统、物理量场等方面对2013年6月27—29日连续性暴雨过程进行分析,得出结论:(1)LAPS输出的产品时效性好,分辨率高,产品多样化,更好地丰富了对天气过程分析的方法,对中尺度天气具有非常明确的解释能力,有利于从更深层次分析天气发生的成因;(2)高纬有阻高建立,低纬度地区受南亚高压控制,系统稳定少动,中纬度地区不断有短波槽东移,引导冷空气南下,副高西北侧强盛的西南气流将暖湿空气源源不断地输入江西中北部,在此形成冷暖交汇,稳定的形势有利于形成连续性暴雨天气;(3)副高西北侧的强西南急流中,风向风速在江西中北部辐合,为强降水提供了抬升条件,并且急流的脉动与降水强度的变化有着密切关系,强降水往往出现在凌晨前后,下午至晚上逐渐减弱。 展开更多
关键词 LAPS资料 暴雨 天气预报
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移动代理的故障模型分析 被引量:1
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作者 程欣 杨孝宗 《计算机工程与应用》 CSCD 北大核心 2003年第13期16-18,共3页
容错是移动代理系统实现的重要条件。该文提出移动代理的故障模型分类方法LAPSe。介绍了基于暂存复制和基于空间复制分类方法,据此分类方法比较了部分现有移动代理容错模型,结论是:其中基于空间复制类的代理系统容错性能最好。讨论了移... 容错是移动代理系统实现的重要条件。该文提出移动代理的故障模型分类方法LAPSe。介绍了基于暂存复制和基于空间复制分类方法,据此分类方法比较了部分现有移动代理容错模型,结论是:其中基于空间复制类的代理系统容错性能最好。讨论了移动代理的容错研究需要解决的关键问题。 展开更多
关键词 容错 故障模型分类 lapse
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时间延迟及螺旋自动启动技术在多层螺旋CT腹部增强扫描中的应用 被引量:1
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作者 顾欣 《医疗装备》 2006年第1期18-19,共2页
目的:探讨时间延迟分析软件及螺旋自动启动技术在多层螺旋CT腹部增强扫描中的应用价值。方法:应用时间延迟软件确定个性化的各动态增强扫描期的时间,并应用SAS技术与高压注射器联动,对20例患者行腹部螺旋CT增强扫描。结果:针对个性化的... 目的:探讨时间延迟分析软件及螺旋自动启动技术在多层螺旋CT腹部增强扫描中的应用价值。方法:应用时间延迟软件确定个性化的各动态增强扫描期的时间,并应用SAS技术与高压注射器联动,对20例患者行腹部螺旋CT增强扫描。结果:针对个性化的扫描期相,采集到的图像可分辨的期相也相应更加细腻。结论:采用时间延迟分析软件及螺旋自动启动技术,使多层螺旋CT采集的速度更快,时间分辨力提高,增加了对很多病变的识别能力。 展开更多
关键词 时间延迟(Time lapse) 螺旋自动启动(Spiral Automatic Start SAS) 多层螺旋CT(MSCT)
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Identifying Distinct Quitting Trajectories after an Unassisted Smoking Cessation Attempt: An Ecological Momentary Assessment Study
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作者 Monica S. Bachmann Hansjorg Znoj Jeannette Brodbeck 《Open Journal of Medical Psychology》 2012年第3期44-50,共7页
Objectives: This study aimed at identifying distinct quitting trajectories over 29 days after an unassisted smoking ces- sation attempt by ecological momentary assessment (EMA). In order to validate these trajectories... Objectives: This study aimed at identifying distinct quitting trajectories over 29 days after an unassisted smoking ces- sation attempt by ecological momentary assessment (EMA). In order to validate these trajectories we tested if they predict smoking frequency up to six months later. Methods: EMA via mobile phones was used to collect real time data on smoking (yes/no) after an unassisted quit attempt over 29 days. Smoking frequency one, three and six months after the quit attempt was assessed with online questionnaires. Latent class growth modeling was used to analyze the data of 230 self-quitters. Results: Four different quitting trajectories emerged: quitter (43.9%), late quitter (11.3%), returner (17%) and persistent smoker (27.8%). The quitting trajectories predicted smoking frequency one, three and six months after the quit attempt (all p < 0.001). Conclusions: Outcome after a smoking cessation attempt is better described by four distinct trajectories instead of a binary variable for abstinence or relapse. In line with the relapse model by Marlatt and Gordon, late quitter may have learned how to cope with lapses during one month after the quitting attempt. This group would have been allocated to the relapse group in traditional outcome studies. 展开更多
关键词 Smoking Cessation lapse Relapse Process Ecological Momentary Assessment Self-Quitter
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中国南方暴雨野外试验中尺度气象分析场的建立及其质量评估 被引量:23
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作者 崔春光 倪允琪 +4 位作者 李红莉 彭菊香 张艳霞 邱学兴 许晓林 《气象学报》 CAS CSCD 北大核心 2011年第1期26-40,共15页
利用武汉暴雨研究所从美国引进的LAPS中尺度分析系统,将2008年和2009年5—7月中国南方暴雨野外科学试验(SCHeREX)中所采集的观测资料进行融合、同化,生成了华南、华中、江淮和长江三角洲4个观测区的空间分辨为5 km、时间分辨为3 h的SHCe... 利用武汉暴雨研究所从美国引进的LAPS中尺度分析系统,将2008年和2009年5—7月中国南方暴雨野外科学试验(SCHeREX)中所采集的观测资料进行融合、同化,生成了华南、华中、江淮和长江三角洲4个观测区的空间分辨为5 km、时间分辨为3 h的SHCeREX中尺度气象分析场。文中从两方面对SCHeREX中尺度分析场的质量进行了评估分析。首先,根据野外试验期间在4个观测区出现的暴雨日,结合观测的雷达回波和卫星云图云顶亮温(TBB)资料与SCHeREX中尺度分析资料进行统计分析与比较,结果表明,SCHeREX中尺度分析资料对中尺度强对流系统具有很强的再现能力。同时,以探空观测资料为基准,分析计算了SCHeREX中尺度分析场的平均偏差、平均均方根误差及其随高度的分布,分析结果表明SCHeREX中尺度分析场的位势高度、温度、相对湿度、风向和风速的分析误差均在观测误差范围内,尤其是SCHeREX中尺度分析场700—925 hPa位势高度的平均分析误差为45 gpm,温度的平均分析误差为1.0-1.1℃,相对湿度的平均分析误差不超过20%,风速的平均误差为1.5—2.0m/s,风向为20°—25°。 展开更多
关键词 LAPS 诊断分析 融合和同化 适用性 质量评估
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中尺度分析系统LAPS应用雷达资料的个例研究 被引量:31
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作者 李红莉 崔春光 +2 位作者 王志斌 王晓芳 谢有才 《高原气象》 CSCD 北大核心 2009年第6期1443-1452,共10页
武汉暴雨所引进国际先进的中尺度分析系统LAPS,经成功本地移植后,该系统能融合华中区域多种非常规观测资料,提供包含丰富中尺度信息的高分辨率中尺度分析场。针对一次梅雨期强降水过程,利用LAPS系统进行中尺度分析,通过对比该系统融合... 武汉暴雨所引进国际先进的中尺度分析系统LAPS,经成功本地移植后,该系统能融合华中区域多种非常规观测资料,提供包含丰富中尺度信息的高分辨率中尺度分析场。针对一次梅雨期强降水过程,利用LAPS系统进行中尺度分析,通过对比该系统融合多普勒雷达资料前后各种物理量场的差异,研究了多普勒雷达资料在该系统中的作用。结果表明,LAPS融合雷达径向风后,对风场的改善比较明显,能揭示流场的中尺度信息。融合多种资料后的LAPS中尺度分析场比NCEP再分析场更接近实况,能清楚地反映中尺度特征,可作为分析此次强降水过程发生、发展的工具。融合雷达资料反射率后,LAPS云分析能提供与实况接近的较细致的云信息,有利于了解暴雨过程中云参数的演变,同时也为数值模式热启动提供条件。 展开更多
关键词 LAPS系统 中尺度分析 云分析 多普勒雷达资料
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