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Improved nuclear magnetic resonance-based Green-Ampt infiltration model incorporating dynamic permeability of clay
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作者 TAO Gaoliang ZHOU Hengjie +3 位作者 CHEN Qingsheng NIMBALKAR Sanjay LIAO Lingjin PENG Pai 《Journal of Mountain Science》 2025年第10期3690-3705,共16页
The traditional Green-Ampt model does not accurately represent the infiltration behavior of clay soils.Infiltration in clay is influenced by low hydraulic conductivity,strong capillary forces,and a gradual transition ... The traditional Green-Ampt model does not accurately represent the infiltration behavior of clay soils.Infiltration in clay is influenced by low hydraulic conductivity,strong capillary forces,and a gradual transition zone between saturated and unsaturated zones.These factors often lead to overestimated infiltration rates and underestimated infiltration durations.Therefore,it is necessary to improve the model to better reflect the characteristics of clay infiltration and enhance its predictive accuracy and practical applicability.This study conducts hydraulic characterization tests,one-dimensional soil column rainfall infiltration experiments,and numerical analysis on a representative clay sampled from Wuhan,China,to investigate infiltration behaviors under varying rainfall intensities and initial moisture conditions.The study reveals that the proportion of the transition layer within the wetting layer decreases with increasing wetting front depth,following a power-law function.Under the same initial moisture content,this proportion tends to converge to a stable value regardless of rainfall intensity.In contrast,under the same rainfall intensity,a higher initial moisture content leads to a larger proportion of the transition layer at a given wetting front depth.Based on the NMR curve,the unsaturated permeability coefficients corresponding to different volumetric water contents of clay can be obtained quickly,accurately,and at low cost.By utilizing the unsaturated permeability coefficient prediction model based on the nuclear magnetic resonance(NMR)curve,the study refines the computational method for the equivalent permeability coefficient in the wetting layer during clay rainfall infiltration,and proposes an improved clay Green-Ampt infiltration model that considers the saturated-unsaturated differentiation layer and the dynamic variation of its equivalent permeability coefficient under continuous rainfall conditions.The computational results of the improved model were compared with measured infiltration data,numerical simulations,and predictions from the traditional GA model.The results indicate that the improved model effectively captures the dynamic variation between the transition layer and wetting layer and provides more accurate predictions of wetting front depth in clay,with an accuracy approximately 68.36%higher than that of the traditional GA model. 展开更多
关键词 Clay rainfall infiltration Stratification hypothesis NMR equivalent permeability coefficient green Ampt model
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基于改进Green-Ampt模型的土质边坡降雨入渗规律研究
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作者 朱鹏程 杨辉鸿 朱浩锋 《湖南工业大学学报》 2026年第1期9-15,共7页
同时考虑土层初始含水率随深度变化非线性特性、降雨入渗边界条件及饱和与非饱和区动态发展的特点,对Green-Ampt(GA)模型进行修正,并采用参数计算分析的方法,对修正模型的实用性及参数影响规律开展研究。研究结果表明:改进GA模型将降雨... 同时考虑土层初始含水率随深度变化非线性特性、降雨入渗边界条件及饱和与非饱和区动态发展的特点,对Green-Ampt(GA)模型进行修正,并采用参数计算分析的方法,对修正模型的实用性及参数影响规律开展研究。研究结果表明:改进GA模型将降雨入渗过程细分为3个阶段,推导出了对应的时间边界条件以及各阶段降雨历时与湿润锋及饱和区深度的计算公式;降雨强度较小时,降雨入渗过程分为3个阶段,但随着降雨强度的增加,降雨入渗过程可以简化为2个阶段;初始含水率分布模式对土体入渗时间边界条件、湿润锋与饱和区深度具有显著的影响。随着降雨历时增加,指数分布模式湿润锋深度发展较定值分布模式发展更快,且降雨入渗初期,初始含水率分布模式对参数ξ影响较大,但随着降雨历时增加,对ξ影响逐渐可以被忽略。 展开更多
关键词 改进green-Ampt模型 土质边坡 初始含水率 入渗规律 湿润锋
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基于标量Green函数的各向异性介质电阻率法三维正演
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作者 徐志锋 熊心如 +3 位作者 熊彬 石靖 陆裕国 李明晟 《地球物理学报》 北大核心 2025年第10期4005-4011,共7页
自然条件下,有些金属矿床赋存于沉积、变质岩层中.由于沉积旋回和构造挤压,大多数沉积岩和一部分变质岩往往具有层状结构,它们的导电性具有明显的方向性,有时垂直层理方向的电阻率ρn比沿着层理方向的电阻率ρt大好几倍.岩层的各向异性... 自然条件下,有些金属矿床赋存于沉积、变质岩层中.由于沉积旋回和构造挤压,大多数沉积岩和一部分变质岩往往具有层状结构,它们的导电性具有明显的方向性,有时垂直层理方向的电阻率ρn比沿着层理方向的电阻率ρt大好几倍.岩层的各向异性使得理想条件下(均匀、各向同性)的电场分布规律发生畸变,直接导致电法勘查后续推断解释工作复杂化.基于此,本文针对电导率各向异性介质开展电阻率法三维正演研究.首先,引入标量Green函数,形成各向异性介质中Green函数的全新表达,消除点电流源附近场的奇异性,实现了面向总电位的各向异性地电模型中电阻率法数值模拟;其次,通过均匀半空间各向异性模型验证文中提出算法的计算精度;然后,定义各向异性电阻率法视电阻率,利用垂直接触面上的Wenner剖面曲线展示本文算法的适用性;最后,以地下赋存方形目标体为例,计算视电阻率,考察介质电导率非各向同性对电阻率响应的影响,识别地下介质各向异性特征.模型计算结果表明,本文研究成果一方面降低了传统算法的复杂度,一方面大幅度提高了计算精度,有望在电法勘查的其他分支类方法中获得积极应用. 展开更多
关键词 电阻率法 各向异性 正演 green函数 总电位
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Indocyanine green clearance test and model for end-stage liver disease score of patients with liver cirrhosis 被引量:37
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作者 Sheng, Qin-Song Lang, Ren +3 位作者 He, Qiang Yang, Yong-Jiu Zhao, De-Fang Chen, Da-Zhi 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第1期46-49,共4页
BACKGROUND: The indocyanine green (ICG) clearance test (clearance rate (K) and retention rate at 15 minutes (R(15))) is a sensitive indicator to evaluate liver function. The model for end-stage liver disease (MELD) sc... BACKGROUND: The indocyanine green (ICG) clearance test (clearance rate (K) and retention rate at 15 minutes (R(15))) is a sensitive indicator to evaluate liver function. The model for end-stage liver disease (MELD) score has emerged as a useful tool for estimating the mortality of patients awaiting liver transplantation and has recently been validated on patients with liver diseases of various etiologies and severity. In this study, we investigated the correlation between the ICG clearance test and MELD score of patients with liver cirrhosis. METHODS: From June 2007 to March 2008, 52 patients with liver cirrhosis admitted to our center were classified into Child-Pugh class A (8 patients), B (14) and C (30). The ICG clearance test (K value and R(15)) was performed by ICG pulse spectrophotometry (DDG-3300K), and the MELD scores of patients were calculated. RESULTS: As the Child-Pugh classification of liver function gradually deteriorated, the K value decreased, while R(15) and MELD score increased. There were significant statistical differences in K value, R(15) and MELD score in patients with different Child-Pugh classifications. Significant correlations were found between the parameters of the ICG clearance test (K value and R(15)) and MELD score. A negative correlation was observed between K value and MELD score (r=-0.892, P < 0.05), while a positive correlation was observed between R(15) and MELD score (r=0.804, P < 0.05). CONCLUSIONS: The ICG clearance test and MELD score are good parameters for evaluating liver function. Moreover, K value and R(15) have significant correlations with MELD score, especially the K value, which may be a convenient and appropriate indicator to evaluate liver function of patients with liver cirrhosis. 展开更多
关键词 liver function tests indocyanine green model for end-stage liver disease SPECTROPHOTOMETRY
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Spatial distribution prediction and benefits assessment of green manure in the Pinggu District,Beijing,based on the CLUE-S model 被引量:14
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作者 ZHANG Li-ping ZHANG Shi-wen +3 位作者 ZHOU Zhi-ming HOU Sen HUANG Yuan-fang CAO Wei-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第2期465-474,共10页
Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in mo... Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in more attention to green manure.Human intervention and policy-oriented behaviors likely have large impacts on promoting green manure planting.However,little information is available regarding on where,at what rates,and in which ways(i.e.,intercropping green manure in orchards or rotating green manure in cropland) to develop green manure and what benefits could be gained by incorporating green manure in fields at the county scale.This paper presents the conversion of land use and its effects at small region extent(CLUE-S) model,which is specifically developed for the simulation of land use changes originally,to predict spatial distribution of green manure in cropland and orchards in 2020 in Pinggu District located in Beijing,China.Four types of land use for planting or not planting green manure were classified and the future land use dynamics(mainly croplands and orchards) were considered in the prediction.Two scenarios were used to predict the spatial distribution of green manure based on data from 2011:The promotion of green manure planting in orchards(scenario 1) and the promotion of simultaneous green manure planting in orchards and croplands(scenario 2).The predictions were generally accurate based on the receiver operating characteristic(ROC) and Kappa indices,which validated the effectiveness of the CLUE-S model in the prediction.In addition,the spatial distribution of the green manure was acquired,which indicated that green manure mainly located in the orchards of the middle and southern regions of Dahuashan,the western and southern regions of Wangxinzhuang,the middle region of Shandongzhuang,the eastern region of Pinggu and the middle region of Xiagezhuang under scenario 1.Green manure planting under scenario 2 occurred in orchards in the middle region of Wangxinzhuang,and croplands in most regions of Daxingzhuang,southern Pinggu,northern Xiagezhuang and most of Mafang.The spatially explicit results allowed for the assessment of the benefits of these changes based on different economic and ecological indicators.The economic and ecological gains of scenarios 1 and 2 were 175691 900 and143000 300 CNY,respectively,which indicated that the first scenario was more beneficial for promoting the same area of green manure.These results can facilitate policies of promoting green manure and guide the extensive use of green manure in local agricultural production in suitable ways. 展开更多
关键词 CLUE-S model green manure spatial distribution prediction benefits assessment
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Green development model and cultivating path for characteristic small town 被引量:2
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作者 ZHANG Yu-meng 《Ecological Economy》 2017年第1期80-88,共9页
In the context of the new urbanization,the characteristic town,as a new hotspot to developing rapidly to explore the industry,humanities,community integration town model,a urbanization and high-tech industry developme... In the context of the new urbanization,the characteristic town,as a new hotspot to developing rapidly to explore the industry,humanities,community integration town model,a urbanization and high-tech industry development booster,by the government and developers attention.At the same time,the green development model applies to the characteristic town of industrial upgrading and transformation,guiding the future characteristic town of green economic industry development direction.This paper studies the green development model of the characteristic town,and puts forward the implementation of the green industry through the greening industry structure,promoting green consumption and optimizing the green management. 展开更多
关键词 characteristic town green development model cultivating path
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引入Green函数实现电阻率法总电位高精度三维正演
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作者 熊彬 熊心如 +2 位作者 徐志锋 陆裕国 张健辉 《地球物理学报》 北大核心 2025年第7期2786-2791,共6页
在电阻率法正演中,采用有限单元法数值求解总电位V时,关于总电位V的泛函中含有点电流源项,而位函数V在源点处具有奇异性.为了有效模拟点电流源邻近总电位V的变化情况,人们采用线性插值、二次插值甚至更高次插值,也难以完全消除其影响,... 在电阻率法正演中,采用有限单元法数值求解总电位V时,关于总电位V的泛函中含有点电流源项,而位函数V在源点处具有奇异性.为了有效模拟点电流源邻近总电位V的变化情况,人们采用线性插值、二次插值甚至更高次插值,也难以完全消除其影响,均不能收获令人满意的精度.本文将满足Possion方程的Green函数引入稳定电流场所满足的边值问题,借助Galerkin加权余量法构建有限单元法控制方程,进而实现基于总电位的高精度电阻率法三维正演.理论计算结果表明,本文提出算法的稳定性颇佳,对网格的依赖性低,且计算精度与基于异常电位正演的计算精度相当. 展开更多
关键词 电阻率法 正演 有限单元法 green函数 总电位
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Infiltration,runoff,and slope stability behaviors of infinite slope with macropores based on an improved Green–Ampt model 被引量:1
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作者 LI Shanghui WU Guoxiong +2 位作者 QUE Yun JIANG Zhenliang CHENG Gaoyun 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2220-2235,共16页
Infiltration–runoff–slope instability mechanism of macropore slope under heavy rainfall is unclear.This paper studied its instability mechanism with an improved Green–Ampt(GA)model considering the dual-porosity(i.e... Infiltration–runoff–slope instability mechanism of macropore slope under heavy rainfall is unclear.This paper studied its instability mechanism with an improved Green–Ampt(GA)model considering the dual-porosity(i.e.,matrix and macropore)and ponding condition,and proposed the infiltration equations,infiltration–runoff coupled model,and safety factor calculation method.Results show that the infiltration processes of macropore slope can be divided into three stages,and the proposed model is rational by a comparative analysis.The wetting front depth of the traditional unsaturated slope is 17.2%larger than that of the macropore slope in the early rainfall stage and 27%smaller than that of the macropore slope in the late rainfall stage.Then,macropores benefit the slope stability in the early rainfall but not in the latter.Macropore flow does not occur initially but becomes pronounced with increasing rainfall duration.The equal depth of the wetting front in the two domains is regarded as the onset criteria of macropore flow.Parameter analysis shows that macropore flow is delayed by increasing proportion of macropore domain(ω_(f)),whereas promoted by increasing ratio of saturated permeability coefficients between the two domains(μ).The increasing trend of ponding depth is sharp at first and then grows slowly.Finally,when rainfall duration is less than 3 h,ωf andμhave no significant effect on the safety factor,whereas it decreases with increasingωf and increases with increasingμunder longer duration(≥3 h).With the increase ofω_(f),the slope maximum instability time advances by 10.5 h,and with the increase ofμ,the slope maximum instability time delays by 3.1 h. 展开更多
关键词 Macropore slope green–Ampt infiltration model Equivalent wetting front Ponding response time Slope stability
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Vegetation greenness modeling in response to climate change for Northeast Thailand 被引量:6
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作者 Watinee THAVORNTAM Netnapid TANTEMSAPYA 《Journal of Geographical Sciences》 SCIE CSCD 2013年第6期1052-1068,共17页
In Northeast Thailand, the climate change has resulted in erratic rainfall and tem- perature patterns. The region has experienced both periods of drought and seasonal floods with the increasing severity. This study in... In Northeast Thailand, the climate change has resulted in erratic rainfall and tem- perature patterns. The region has experienced both periods of drought and seasonal floods with the increasing severity. This study investigated the seasonal variation of vegetation greenness based on the Normalized Difference Vegetation Index (NDVI) in major land cover types in the region. An assessment of the relationship between climate patterns and vegeta- tion conditions observed from NDVI was made. NDVI data were collected from year 2001 to 2009 using multi-temporal Terra MODIS Vegetation Indices Product (MOD13Q1). NDVI pro- files were developed to measure vegetation dynamics and variation according to land cover types. Meteorological information, i.e. rainfall and temperature, for a 30 year time span from 1980 to 2009 was analyzed for their patterns. Furthermore, the data taken from the period of 2001-2009, were digitally encoded into GIS database and the spatial patterns of monthly rainfall and temperature maps were generated based on kriging technique. The results showed a decreasing trend in NDVI values for both deciduous and evergreen forests. The highest productivity and biomass were observed in dry evergreen forests and the lowest in paddy fields. Temperature was found to be increasing slightly from 1980 to 2009 while no significant trends in rainfall amounts were observed. In dry evergreen forest, NDVI was not correlated with rainfall but was significant negatively correlated with temperature. These re- sults indicated that the overall productivity in dry evergreen forest was affected by increasing temperatures. A vegetation greenness model was developed from correlations between NDVI and meteorological data using linear regression. The model could be used to observe the change in vegetation greenness and dynamics affected by temperature and rainfall. 展开更多
关键词 Normalized Difference Vegetation Index (NDVI) vegetation greenness climate variability modelING
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上覆碳酸盐岩红土层对磷石膏水分运移的影响及Green-Ampt模型模拟 被引量:1
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作者 陈浩 刘冬冬 +2 位作者 冯娜 杨娅 唐俊杰 《水土保持通报》 北大核心 2025年第1期225-234,共10页
[目的]分析上覆碳酸盐岩红土对磷石膏入渗特性的影响机制,为西南喀斯特地区磷石膏堆场合理处置及利用提供科学依据。[方法]通过室内扁平土柱入渗试验研究3种磷石膏容重(1.2,1.3,1.4 g/cm^(3))和3种上覆土层厚度(0,6,12 cm)对磷石膏水分... [目的]分析上覆碳酸盐岩红土对磷石膏入渗特性的影响机制,为西南喀斯特地区磷石膏堆场合理处置及利用提供科学依据。[方法]通过室内扁平土柱入渗试验研究3种磷石膏容重(1.2,1.3,1.4 g/cm^(3))和3种上覆土层厚度(0,6,12 cm)对磷石膏水分入渗过程的影响,并通过改进的分层型Green-Ampt模型进行入渗过程数值模拟。[结果](1)6和12 cm覆土厚度处理下水分入渗到底部的时间差异不显著(p>0.05),而在0与6 cm、0与12 cm覆土厚度处理下入渗时间差异显著(p<0.05)。覆土厚度为0 cm的初始入渗率、平均入渗率和稳定入渗率显著高于6,12 cm的初始入渗率、平均入渗率和稳定入渗率(p<0.05),稳定入渗率随覆土厚度增大而显著减小。6,12 cm覆土厚度累积入渗量差异不显著(p>0.05),其余覆土厚度之间累积入渗量差异显著(p<0.05)。(2)相同覆土厚度下,磷石膏容重对初始入渗率、平均入渗率和稳定入渗率的影响均不显著(p>0.05)。(3)湿润峰深度实测值与模拟值决定系数(R^(2))变化范围为0.951~0.995,均方根误差(RMSE)为12.174~40.856,平均绝对百分比误差(MAPE)为0.070~0.227。覆土6和12 cm时,累积入渗量实测值与模拟值决定系数(R~2)变化范围为0.963~0.999,均方根误差(RMSE)为1.471~11.201,平均绝对百分比误差(MAPE)为0.046~0.169。[结论]磷石膏覆土与未覆土的土壤水分入渗特征存在显著差异,改进的分层型Green-Ampt模型能够用于模拟上覆土层条件下磷石膏的入渗过程。 展开更多
关键词 覆土 磷石膏 水分运移 green-AMPT模型
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Evaluating Model Effectiveness for Soil Infiltration Attribute: Comparison of Green-Ampt, Horton and Modified Green-Ampt Infiltration Models 被引量:1
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作者 Mosammat Mustari Khanaum Md. Saidul Borhan 《Journal of Geoscience and Environment Protection》 2023年第2期57-68,共12页
Soil infiltration is a very important concept in hydrology as well as irrigation, which plays a vital role in estimating surface runoff and groundwater recharge. It is a complicated process that varies with numerous f... Soil infiltration is a very important concept in hydrology as well as irrigation, which plays a vital role in estimating surface runoff and groundwater recharge. It is a complicated process that varies with numerous factors. Accurate estimation of soil infiltration is required for future irrigation, and many other purposes. To estimate the infiltration process, there are numerous models. The majority of them have some presumptions, a unique calculation method, and some limitations. The purpose of the paper was to assess the model’s performance for a similar hypothetical scenario involving soil infiltration. It compared the infiltration rate, runoff rate, and incremental infiltration versus time for three different infiltration models: the Green-Ampt model (GA), the Horton model and the Modified Green-Ampt (MGA) model. A spreadsheet was used to calculate the Horton model, and HYDROL-INF (V 5.03) was used to simulate the other two models. Among those three models, the MGA model outperformed those three models, while the GA model produced greater infiltration rate than rainfall, which was insensible. The study showed that the MGA model, which provides useful infiltration predictions, outperformed the other two infiltration models. Since the Horton model does not consider ponding conditions, it is only applicable when the effective rainfall intensity exceeds the final infiltration capacity. Moreover, the GA model’s initial infiltration rate is irrational because it disregards the intensity of the rainfall. The results of this study will assist in selecting the most accurate method for estimating soil infiltration for agricultural purposes. 展开更多
关键词 INFILTRATION Groundwater Recharge green-Ampt Horton model Modified green-Ampt
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Green Investment Cost Optimization Model in the Supply Chain 被引量:2
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作者 Seungbae Sim Hosang Jung 《American Journal of Operations Research》 2013年第6期454-462,共9页
The objective of this study is to develop a model that determines the optimal points for investment in green management by defining a mathematical relationship between carbon trading profits and investments in green m... The objective of this study is to develop a model that determines the optimal points for investment in green management by defining a mathematical relationship between carbon trading profits and investments in green management using a company’s supply chain information. To formulate this model, we first define and analyze a green supply chain in a multi-dimensional and quantitative manner. The green investment alternatives considering in our model are as follows: 1) purchasing eco-friendly raw materials that cost more than conventional raw materials but whose use in production results in lower CO2 emissions;2) replacing current facilities with new eco-friendly facilities that have the capability to reduce CO2 emissions;and 3) changing modes of transport from less eco-friendly to more eco-friendly modes. We propose a green investment cost optimization (GICO) model that enables us to determine the optimal investment points. The proposed GICO model can support decision-making processes in green supply chain management environments. 展开更多
关键词 green INVESTMENT COST OPTIMIZATION model in the Supply CHAIN
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Edgeworth expansion for the survival function estimator in the Koziol-Green model
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作者 吴国富 孙六全 《Science China Mathematics》 SCIE 2002年第6期681-693,共13页
In the Koziol-Green or proportional hazards random censorship model, the asymptotic accuracy of the estimated one-term Edgeworth expansion and the smoothed bootstrap approximation for the Studentized Abdushukurov-Chen... In the Koziol-Green or proportional hazards random censorship model, the asymptotic accuracy of the estimated one-term Edgeworth expansion and the smoothed bootstrap approximation for the Studentized Abdushukurov-Cheng-Lin estimator is investigated. It is shown that both the Edgeworth expansion estimate and the bootstrap approximation are asymptotically closer to the exact distribution of the Studentized Abdushukurov-Cheng-Lin estimator than the normal approximation. 展开更多
关键词 censoring Abdushukurov-Cheng-Lin estimator Koziol-green model Edgeworth EX pansion BOOTSTRAP approximation.
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考虑动荷载诱发路基土水分迁移特性的Green-Ampt模型改进
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作者 许国俊 高峰 +2 位作者 肖林 王夏青 孙润东 《公路交通科技》 北大核心 2025年第10期216-225,共10页
【目标】围绕典型行车动荷载下路基填料水分迁移致灾问题,对传统Green-Ampt模型进行改进,以更准确地评估行车动荷载下路基非饱和土中水分迁移规律。【方法】构建改进Green-Ampt模型,增强模型处理动荷载下土中水分迁移问题的适用性;利用... 【目标】围绕典型行车动荷载下路基填料水分迁移致灾问题,对传统Green-Ampt模型进行改进,以更准确地评估行车动荷载下路基非饱和土中水分迁移规律。【方法】构建改进Green-Ampt模型,增强模型处理动荷载下土中水分迁移问题的适用性;利用自主研制的路基动力加载试验系统,开展非饱和粉砂土水分迁移试验;基于室内试验和模型计算结果,对比分析加载频率对水分迁移量及迁移速率的影响规律,揭示振动荷载下土中湿度场时空演变特性。【结果】通过将振动加速度对湿润锋水势作用等效转化为土体渗透系数变化,构建的改进Green-Ampt模型为动荷载条件下非饱和土水分迁移特征的模拟提供了有效工具,尤其适用于浅层路基土工况;循环动荷载对孔隙水迁移行为具有显著影响,随着加载频率的提高,浅层土体体积含水量增长更为明显,这表明更多孔隙水以更快速度向上迁移,其惯性势在动力加载作用下提高,迁移能力增强;水分迁移速率随时间呈先快速衰减而后逐渐稳定的变化趋势,荷载频率的增加显著提高了初始阶段的迁移速率,这表明动荷载在水分重分布初期作用尤为突出。【结论】改进的Green-Ampt模型的预测精度受土体性质、水分状态及荷载参数等多因素共同制约,后续研究中应重点考虑湿润锋处含水率与基质水头动态变化特性,以进一步提升模型在路基岩土水分迁移评价中的可靠性与适用性。 展开更多
关键词 道路工程 非饱和土 模型改进 水分迁移 green-AMPT模型
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Adsorption of Naphthol Green B on unburned carbon:2-and3-parameter linear and non-linear equilibrium modelling
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作者 Lucie Bartoňová Lucie Ruppenthalová Michal Ritz 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第1期37-44,共8页
The study deals with adsorption of Naphthol Green B on two unburned carbons and the parent coal,from which the UCs have been created in a fluidised-bed power station.Particular attention has been paid to the adsorptio... The study deals with adsorption of Naphthol Green B on two unburned carbons and the parent coal,from which the UCs have been created in a fluidised-bed power station.Particular attention has been paid to the adsorption equilibrium modelling:experimental data has been analysed using 2-parameter(Langmuir,Freundlich) and3-parameter(Redlich-Peterson) isotherms — both linear and non-linear regressions have been used for the estimation of the isotherm parameters.In the case of both UCs,the Langmuir isotherm model provides the worst fit,whereas 2-parameter Freundlich and 3-parameter Redlich-Peterson models are both good,from which 3-parameter Redlich-Peterson isotherm provides slightly better results(despite the penalty used for the higher number of parameters).In the case of both UCs,the linear regression of Freundlich and Redlich-Peterson models provides good results(comparable with non-linear regressions).Unlike both UCs,the best fit of the experimental data from the adsorption on the coal has been achieved by the Langmuir isotherm model.The results based on the Freundlich or Redlich-Peterson model were(in this case) somewhat worse. 展开更多
关键词 Adsorption Unburned carbon Naphthol green B Isotherms Non-linear modelling Redlich-Peterson model
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Model of Cost-benefit Flow in Six Green Projects in China
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作者 ZhuYongjie ZhouBoling 《Forestry Studies in China》 CAS 2003年第3期49-53,共5页
From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have s... From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have some problems unsolved since the model of cost-benefit flow is still centralized and mainly in an administrative way in spite of many efforts made theoretically and practically. It is suggested that a new model based on market-oriented economy from the point of cost-benefit flow with Six Green Projects Management and Policies System consist of complete natural reserve (NR). Management system included environmental nature reserves in addition to biodiversity nature reserve, paid using nature resources, an environmental conservation and construction industry and renewable resource production incentive system that turn the direct administration and operation to management and services. The detail figure of the new model of cost-benefit flow is provided and the main points related are discussed in this paper. 展开更多
关键词 Six green Projects model of cost-benefit flow management and policy frame
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基于渗透系数修正改进Green-Ampt模型的降雨入渗分析
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作者 路喆津 邓珂 +3 位作者 张小东 李好 黄江华 赵炼恒 《水文地质工程地质》 北大核心 2025年第6期77-84,共8页
经典Green-Ampt模型在分析浅层边坡的降雨入渗规律时假定湿润区完全饱和,未考虑入渗过渡带及其对土体渗透系数的影响。为探究边坡的降雨入渗规律,研究土体渗透系数随降雨过程的变化,建立了考虑入渗过渡带的坡体水分剖面理论模型;根据湿... 经典Green-Ampt模型在分析浅层边坡的降雨入渗规律时假定湿润区完全饱和,未考虑入渗过渡带及其对土体渗透系数的影响。为探究边坡的降雨入渗规律,研究土体渗透系数随降雨过程的变化,建立了考虑入渗过渡带的坡体水分剖面理论模型;根据湿润区中过渡带厚度占比关系,基于土体非饱和渗透特性及van Genuthen模型对湿润区土体的实际渗透系数进行修正,建立了改进的Green-Ampt入渗模型。与Richards方程计算结果及已有试验结果对比表明,本理论模型能够较为准确地反映边坡入渗速率和湿润锋推移深度随降雨时间的变化规律,精度高于经典Green-Ampt模型,验证了本模型的准确性。进一步对边坡渗流规律的影响因素进行讨论分析,结果表明:土体入渗速率及湿润锋推移深度受控于降雨强度,降雨强度越大坡体湿润锋推进越快,坡表径流出现的时间越早;不同土体种类具有不同的渗透特性,进而直接影响土体入渗规律,总体而言,粗粒土边坡湿润锋推移最快,黏壤土其次,粉质黏壤土最慢;坡体初始含水率越高,相同的入渗总量下边坡的湿润锋推移深度越大。 展开更多
关键词 非饱和土 渗透系数 green-AMPT模型 土体特性 RICHARDS方程
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A Cost-benefit Measuring Model of Green Products in Manufacturing Industry 被引量:1
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作者 Qingshan Zhang Luping Zhang 《Chinese Business Review》 2005年第5期8-15,共8页
The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products' cost and benefit completely and correctly under the ci... The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products' cost and benefit completely and correctly under the circumstance of satisfying enterprise, customer, environment and society. It also puts forth an operable method to estimate social benefit by opportunity cost and establishes a profit maximization-programming model. The model can be applied to justify whether some kinds of green products should be developed and produced. 展开更多
关键词 green product full life cycle social benefit estimation the measuring model
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A Decision-Making Framework Model of Cutting Fluid Selection for Green Manufacturing and the Case Study 被引量:5
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作者 TAN Xian-chun 1, LIU Fei 1, CAO Hua-jun 1, ZHANG Hua 2 (1. The Institute of Manufacturing Engineering, Chongqing University, Chongqing 400044, China 2. School of Manufacturing & Automation, Wuhan University of Science & Technol ogy, Wuhan 430081, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期136-137,共2页
Pursuing the green manufacturing (GM) of products i s very beneficial in the alleviation of environment burdens. In order to reap such benefits, green manufacturing is involved in every aspect of manufacturing proc es... Pursuing the green manufacturing (GM) of products i s very beneficial in the alleviation of environment burdens. In order to reap such benefits, green manufacturing is involved in every aspect of manufacturing proc esses. During the machining process, cutting fluid is one of the main roots of e nvironmental pollution. And how to make an optimal selection for cutting fluid f or GM is an important path to reduce the environmental pollution. The objective factors of decision-making problems in the traditional selection of cutting flu id are usually two: quality and cost. But from the viewpoint of GM, environmenta l impact (E) should be considered together. In this paper, a multi-object d ecision-making model of cutting fluid selection for GM is put forward, in which the objects of Quality (Q), Cost(C) and Environmental impact (E) are considered together. In this model, E means to minimize the environmental impact, Q means to maximize the quality and C means to minimize the cost. Each objective is anal yzed in detail too. A case study on a decision-making problem of cutting fluid selection in a gear hobbing process is analyzed, and the result shows the model is practical. 展开更多
关键词 green manufacturing cutting fluid decision-mak ing model environmental impact
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考虑垂直入渗的非饱和土Green-Ampt模型改进研究
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作者 马镖 崔宏环 +3 位作者 郭宏燕 张旭 刘军 崔雪刚 《河北建筑工程学院学报》 2025年第2期40-45,64,共7页
为研究持续降雨对泥岩风化带路堤边坡垂直入渗深度的影响,以达西定律和质量守恒方程为基础,结合入渗速率与累积入渗量的微分关联性,提出了Green-Ampt模型的改进形式,提出了可表征华北地区风化泥岩入渗过程的土体降雨入渗公式。基于自制... 为研究持续降雨对泥岩风化带路堤边坡垂直入渗深度的影响,以达西定律和质量守恒方程为基础,结合入渗速率与累积入渗量的微分关联性,提出了Green-Ampt模型的改进形式,提出了可表征华北地区风化泥岩入渗过程的土体降雨入渗公式。基于自制试验装置进行风化泥岩一维垂直入渗试验对所改进的模型进行了验证。试验数据显示,在相同降雨历时条件下,改进后的Green-Ampt模型所预测的湿润锋推进深度与实测结果具有更好的吻合度。研究成果对于构建华北地区风化泥岩路堤边坡降雨入渗预测模型有积极意义。 展开更多
关键词 降雨入渗 风化泥岩 green-AMPT模型 湿润峰
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