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Some Construction Methods of Optimum Chemical Balance Weighing Designs III
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作者 Rashmi Awad Shakti Banerjee 《Open Journal of Statistics》 2016年第1期37-48,共12页
Methods of constructing the optimum chemical balance weighing designs from symmetric balanced incomplete block designs are proposed with illustration. As a by-product pairwise efficiency and variance balanced designs ... Methods of constructing the optimum chemical balance weighing designs from symmetric balanced incomplete block designs are proposed with illustration. As a by-product pairwise efficiency and variance balanced designs are also obtained. 展开更多
关键词 Balanced Incomplete Block Design Symmetric Balanced Incomplete Block Design Ternary Balanced Block Design Variance Balanced Design Efficiency Balanced Design Nested Balanced Incomplete Block Design weighing Design Chemical Balance weighing Design Optimum Chemical Balance weighing Design
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Adjustment of precipitation measurements using Total Rain weighing Sensor(TRwS)gauges in the cryospheric hydrometeorology observation(CHOICE)system of the Qilian Mountains,Northwest China 被引量:1
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作者 ZHAO Yanni CHEN Rensheng +1 位作者 HAN Chuntan WANG Lei 《Journal of Arid Land》 SCIE CSCD 2022年第3期310-324,共15页
Precipitation is one of the most important indicators of climate data,but there are many errors in precipitation measurements due to the influence of climatic conditions,especially those of solid precipitation in alpi... Precipitation is one of the most important indicators of climate data,but there are many errors in precipitation measurements due to the influence of climatic conditions,especially those of solid precipitation in alpine mountains and at high latitude areas.The measured amount of precipitation in those areas is frequently less than the actual amount of precipitation.To understand the impact of climatic conditions on precipitation measurements in the mountainous areas of Northwest China and the applicability of different gauges in alpine mountains,we established a cryospheric hydrometeorology observation(CHOICE)system in 2008 in the Qilian Mountains,which consists of six automated observation stations located between 2960 and 4800 m a.s.l.Total Rain weighing Sensor(TRwS)gauges tested in the World Meteorological Organization-Solid Precipitation Intercomparison Experiment(WMO-SPICE)were used at observation stations with the CHOICE system.To study the influence of climatic conditions on different types of precipitation measured by the TRwS gauges,we conducted an intercomparison experiment of precipitation at Hulu-1 station that was one of the stations in the CHOICE system.Moreover,we tested the application of transfer functions recommended by the WMO-SPICE at this station using the measurement data from a TRwS gauge from August 2016 to December 2020 and computed new coefficients for the same transfer functions that were more appropriate for the dataset from Hulu-1 station.The new coefficients were used to correct the precipitation measurements of other stations in the CHOICE system.Results showed that the new parameters fitted to the local dataset had better correction results than the original parameters.The environmental conditions of Hulu-1 station were very different from those of observation stations that provided datasets to create the transfer functions.Thus,root-mean-square error(RMSE)of solid and mixed precipitation corrected by the original parameters increased significantly by the averages of 0.135(353%)and 0.072 mm(111%),respectively.RMSE values of liquid,solid and mixed precipitation measurements corrected by the new parameters decreased by 6%,20% and 13%,respectively.In addition,the new parameters were suitable for correcting precipitation at other five stations in the CHOICE system.The relative precipitation(RP)increment of different types of precipitation increased with rising altitude.The average RP increment value of snowfall at six stations was the highest,reaching 7%,while that of rainfall was the lowest,covering 3%.Our results confirmed that the new parameters could be used to correct precipitation measurements of the CHOICE system. 展开更多
关键词 automatic weather stations Total Rain weighing Sensors precipitation correction transfer function Qilian Mountains
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A New Correction Method of Electronic-weighing System for Blast Furnace
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作者 Zou Tiepeng Xia Jingbo +1 位作者 Wang Shi Lu Zengxi 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 1998年第2期34-37,共4页
In the injection of pulverized coal into a blast furnace, there are some factors which affect the readout of electronic weighing system. Through analyzing the measuring errors, it is found that the main reasons are p... In the injection of pulverized coal into a blast furnace, there are some factors which affect the readout of electronic weighing system. Through analyzing the measuring errors, it is found that the main reasons are pressure fluctuations of storage tank and puffing tank. According to the interaction of pressures, a neural network based method combined with fuzzy logic is adopted to enhance the precision. Experimental results show this method is satisfactory. 展开更多
关键词 neural network fuzzy logic BP algorithm electronic weighing system
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A Comparison of Weighing Methods Prior to Fusion Preparing Iron Samples for XRF Analysis
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作者 Louis Lefrancois Perreault Mathieu Bouchard 《Journal of Chemistry and Chemical Engineering》 2019年第2期93-100,共8页
Sample preparation by fusion for XRF analysis is all about knowing the exact weights of the sample and the flux (sample-to-flux ratio). The whole analytical chain, including the weighing step in sample preparation pri... Sample preparation by fusion for XRF analysis is all about knowing the exact weights of the sample and the flux (sample-to-flux ratio). The whole analytical chain, including the weighing step in sample preparation prior to fusion, is of crucial importance to get precise and accurate x-ray fluorescence (XRF) results. Consequently, the weighing method will affect the quality of the analytical results given by the spectrometer. In this study, the effects of different weighing methods on the precision (RSD) of the obtained XRF results are compared to determine the best weighing method for sample preparation by fusion in terms of comparable precisions in the XRF results. 展开更多
关键词 weighing METHOD SAMPLE preparation by FUSION tolerance accepted XRF analysis precision accuracy ANALYTICAL METHOD sample-to-flux ratio ANALYTICAL results AUTOMATIC dispensing balance AUTOMATIC weighing instrument
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Some Construction Methods of A-Optimum Chemical Balance Weighing Designs
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作者 Rashmi Awad Shakti Banerjee 《Journal of Applied Mathematics and Physics》 2014年第13期1159-1170,共12页
Some new construction methods of the optimum chemical balance weighing designs and pairwise efficiency and variance balanced designs are proposed, which are based on the incidence matrices of the known symmetric balan... Some new construction methods of the optimum chemical balance weighing designs and pairwise efficiency and variance balanced designs are proposed, which are based on the incidence matrices of the known symmetric balanced incomplete block designs. Also the conditions under which the constructed chemical balance weighing designs become A-optimal are also been given. 展开更多
关键词 BALANCE INCOMPLETE Block DESIGN Symmetric BALANCED INCOMPLETE Block DESIGN Variance BALANCED DESIGN Efficiency BALANCED DESIGN weighing DESIGN CHEMICAL BALANCE weighing DESIGN Optimum CHEMICAL BALANCE weighing DESIGN A-Optimal CHEMICAL BALANCE weighing DESIGN
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Which adjustment methods are suitable for the wind-induced errors of Geonor T-200BM3 precipitation weighing gauges in a periglacial site?
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作者 Lei WANG Ren-Sheng CHEN +3 位作者 Wei-Jun SUN Chun-Tan HAN Bao-Juan HUAI Yan-Ni ZHAO 《Advances in Climate Change Research》 SCIE CSCD 2023年第5期707-719,共13页
Single Alter shielded T-200BM3 weighing precipitation gauges are widely used in the measurement of all precipitation types(rainfall,snow and mixed precipitation)in unattended boreal or alpine regions,but their origina... Single Alter shielded T-200BM3 weighing precipitation gauges are widely used in the measurement of all precipitation types(rainfall,snow and mixed precipitation)in unattended boreal or alpine regions,but their original datasets must be adjusted for undercatch errors caused by wind in snowy,windy and harsh environments.Therefore,previous researchers have developed many adjustment methods for all precipitation types on different time scales.However,which adjustment method is suitable for T-200BM3 weighing gauge wind-induced error adjustment in harsh alpine regions is unclear.Therefore,precipitation measurement intercomparison experiments were conducted in the Qilian Mountains from July 2018 to July 2021,and eight adjustment methods;were evaluated for wind-induced errors for daily,individual precipitation event,hourly,and half-hourly time scales.Z2004 outperformed the other adjustment methods in regard to the daily measurements of snow and mixed precipitation.Regarding individual snowfall events,M2007 reduced the absolute value of RMSE(bias)from 1.44 to 1.32 mm(0.77-0.24 mm)and could be recommended for snowfall event adjustment.K2017-1 attained a better performance than K2017-2 in regard to half-hourly snowfall and mixed sample adjustment and was more suitable for half-hourly snowfall sample adjustment.K2017-1 reduced the absolute value of bias from 0.07 to 0.00 mm for snowfall.Finally,Z2004,M2007,and K2017-1 yielded better adjustment results for the daily accumulation precipitation amount(>2 mm d−1),individual snowfall events(>2 mm per event),and half-hourly accumulation snowfall or mixed samples(>1 mm 30 min−1),respectively.However,further intercomparison in different climate regions is needed for trace precipitation samples. 展开更多
关键词 Evaluation Wind-induced errors Adjustment methods weighing gauges Periglacial site
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DEVELOPMENT OF AN AUTOMATIC WEIGHING PLATFORM FOR MONITORING BODYWEIGHT OF BROILER CHICKENS IN COMMERCIAL PRODUCTION
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作者 Danni ZHOU Yi ZHOU +4 位作者 Pengguang HE Lin YU Jinming PAN Lilong CHAI Hongjian LIN 《Frontiers of Agricultural Science and Engineering》 CSCD 2023年第3期363-373,共11页
Bodyweight is a key indicator of broiler production as it measures the production efficiency and indicates the health of a flock.Currently,broiler weight(i.e.,bodyweight)is primarily weighed manually,which is timecons... Bodyweight is a key indicator of broiler production as it measures the production efficiency and indicates the health of a flock.Currently,broiler weight(i.e.,bodyweight)is primarily weighed manually,which is timeconsuming and labor-intensive,and tends to create stress in birds.This study aimed to develop an automatic and stress-free weighing platform for monitoring the weight of floor-reared broiler chickens in commercial production.The developed system consists of a weighing platform,a real-time communication terminal,computer software and a smart phone applet userinterface.The system collected weight data of chickens on the weighing platform at intervals of 6 s,followed by filtering of outliers and repeating readings.The performance and stability of this system was systematically evaluated under commercial production conditions.With the adoption of data preprocessing protocol,the average error of the new automatic weighing system was only 10.3 g,with an average accuracy 99.5%with the standard deviation of 2.3%.Further regression analysis showed a strong agreement between estimated weight and the standard weight obtained by the established live-bird sales system.The variance(an indicator of flock uniformity)of broiler weight estimated using automatic weighing platforms was in accordance with the standard weight.The weighing system demonstrated superior stability for different growth stages,rearing seasons,growth rate types(medium-and slow-growing chickens)and sexes.The system is applicable for daily weight monitoring in floor-reared broiler houses to improve feeding management,growth monitoring and finishing day prediction.Its application in commercial farms would improve the sustainability of poultry industry. 展开更多
关键词 automatic weighing weight monitoring floor housing UNIFORMITY precision poultry farming
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Upgrade and Renovation of Steel Billet Scalein front of High-speed Wire Furnace
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作者 Xiao Chen 《Frontiers of Metallurgical Industry》 2024年第2期43-46,共4页
This article briefly introduces the weighing device for steel billets in front of the heating furnace of the high-speed wire rod unit,and analyzes and summarizes the problems existing in the original weighing device f... This article briefly introduces the weighing device for steel billets in front of the heating furnace of the high-speed wire rod unit,and analyzes and summarizes the problems existing in the original weighing device for steel billets in production and use.Based on on-site installation conditions,design a new weighing method,match a large range weighing sensor,upgrade the automation control of the weighing device,and remotely transmit the billet weighing data to the MES system of the group.The automatic,stable,reliable,and accurate measurement of steel billet raw materials has been achieved,providing important guarantees for the accurate measurement of production line billet and product yield. 展开更多
关键词 weighing device gate type boom type weighing sensor
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A method for weighing broiler chickens using improved amplitude-limiting filtering algorithm and BP neural networks 被引量:6
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作者 Weihong Ma Qifeng Li +2 位作者 Jiawei Li Luyu Ding Qinyang Yu 《Information Processing in Agriculture》 EI 2021年第2期299-309,共11页
Broiler chickens are traditionally weighed by steelyard or platform scale,which is timeconsuming and labor-intensive.Broiler chickens usually exhibit stress-related behavior during weighing.The 3D camera-based weighin... Broiler chickens are traditionally weighed by steelyard or platform scale,which is timeconsuming and labor-intensive.Broiler chickens usually exhibit stress-related behavior during weighing.The 3D camera-based weighing system for broiler chickens can only weigh the broiler chicken in the monitoring area.Usually,it makes poor weight prediction due to poor segmentation especially when the broiler chicken is flapping its wings.To solve these issues,we developed one simple and low-cost weighing system with high stability and accuracy.A validity value extraction method from dynamic weighing was proposed.Then,an improved amplitude-limiting filtering algorithm and a BP neural networks model were developed to avoid accidental interference.The BP neural networks model used daily weight gain,day-age,average velocity,and the weight data after filtering algorithm as the input layer.The weighing system was tested in a commercial Beijing Fatty Chickens house with Beijing Fatty Chickens.We tested thirteen groups of Beijing Fatty Chickens of different weights,from 500 g to 1800 g in intervals of 100 g,using the three different methods:no filtering algorithm or BP neural networks,only the improved amplitude-limiting filtering algorithm and a hybrid of the improved amplitude-limiting filtering algorithm and BP neural networks.The results showed that the hybrid algorithm had a better performance in minimizing the error,lowering from the original 6%down to 3%.The accurate weight data was transmitted to the remote service platform for further decision-making,such as activity analysis,feeding management,and health alerts. 展开更多
关键词 weighing of broiler chickens Improved amplitude-limiting filtering algorithm BP neural networks Dynamic weighing
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Changes of coastline and tidal flat and its implication for ecological protection under human activities: Take China’s Bohai Bay as an example
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作者 Yong Li Ming-zheng Wen +3 位作者 Heng Yu Peng Yang Fei-cui Wang Fu Wang 《China Geology》 CAS CSCD 2024年第1期26-35,共10页
The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecologic... The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecological environment changes and even global changes.Based on field measurements,combined with Linear Regression(LR)model and Inverse Distance Weighing(IDW)method,this paper presents detailed analysis on the change history and trend of the shoreline and tidal flat in Bohai Bay.The shoreline faces a high erosion chance under the action of natural factors,while the tidal flat faces a different erosion and deposition patterns in Bohai Bay due to the impact of human activities.The implication of change rule for ecological protection and recovery is also discussed.Measures should be taken to protect the coastal ecological environment.The models used in this paper show a high correlation coefficient between observed and modeling data,which means that this method can be used to predict the changing trend of shoreline and tidal flat.The research results of present study can provide scientific supports for future coastal protection and management. 展开更多
关键词 SHORELINE Tidal flat Erosion deposition patterns Changing trend Ecological protection Human activity Linear regression model Inverse distance weighing method Prediction Bohai Bay
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Enhancing the accuracy of area extraction in machine vision-based pig weighing through edge detection 被引量:9
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作者 Yongsheng Wang Wade Yang +1 位作者 Lloyd T.Walker Taha M.Rababah 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2008年第1期37-42,共6页
The accuracy of extracting projected pig area is critical to the accuracy of the weight measurement of pigs by machine vision.The capability of both the conventional and the edge detection methods for extracting pig a... The accuracy of extracting projected pig area is critical to the accuracy of the weight measurement of pigs by machine vision.The capability of both the conventional and the edge detection methods for extracting pig area was examined using the images of 47 pigs of different weights.Relationship between the threshold value and the extracted area was numerically analyzed for both methods.It was found that the accuracy of the conventional method depended heavily on the threshold value,while choice of threshold value in the edge detection approach had no influence on the extracted area over a wide range.In normal lighting conditions,both methods yielded comparable values of predicted weight;however,under variable light intensities,the edge detection method was superior to the conventional method,because the former was proven to be independent of light intensities.This makes edge detection an ideal method for area extraction during the walk-through weighing process where pigs are allowed to move around. 展开更多
关键词 Area extraction edge detection threshold value pig weighing machine vision image processing
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Convergence rate of principal component analysis with local-linear smoother for functional data under a unified weighing scheme 被引量:1
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作者 Xingyu Yan Xiaolong Pu +1 位作者 Yingchun Zhou Xiaolei Xun 《Statistical Theory and Related Fields》 2020年第1期55-65,共11页
The unified weighing scheme for the local-linear smoother in analysing functional data can deal with data that are dense,sparse or of neither type.In this paper,we focus on the convergence rate of functional principal... The unified weighing scheme for the local-linear smoother in analysing functional data can deal with data that are dense,sparse or of neither type.In this paper,we focus on the convergence rate of functional principal component analysis using this method.Almost sure asymptotic consistency and rates of convergence for the estimators of eigenvalues and eigenfunctions have been established.We also provide the convergence rate of the variance estimation of the measurement error.Based on the results,the number of observations within each curve can be of any rate relative to the sample size,which is consistent with the earlier conclusions about the asymptotic properties of the mean and covariance estimators. 展开更多
关键词 Functional principal components asymptotic properties local-linear smoothing weighing scheme
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Simple weighing lysimeters for measuring evapotranspiration and developing crop coefficients
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作者 Daniel K.Fisher 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2012年第3期35-43,共9页
Knowledge of cotton crop evapotranspiration(ET)is important in scheduling irrigations,optimizing crop production,and modeling ET and crop growth.The ability to measure,estimate,and predict ET and cotton crop water req... Knowledge of cotton crop evapotranspiration(ET)is important in scheduling irrigations,optimizing crop production,and modeling ET and crop growth.The ability to measure,estimate,and predict ET and cotton crop water requirements can result in better satisfying the crop’s water needs and improving water use efficiency.Weighing lysimeters have been used for many years to measure and study water use,and to develop crop-coefficient functions necessary in estimating ET.Electronic weighing lysimeters,consisting of a steel outer tank and inner tank,electronic loadcell assemblies,and a PVC drain system,were designed,constructed,and installed.Each lysimeter cost approximately US$1700(in 2001)in materials,required two people and 40 hours of labor to construct,and were installed by two people using minimal excavation and hand tools.Daily ET data for cotton were collected from 2003 to 2006 to quantify cotton water-use and to develop crop coefficient functions.Seasonal water use ranged generally from 2 to 8 mm/d.Seasonal water-use patterns varied considerably among growing seasons due to variable environmental and crop-growth conditions,making determination of an“average”crop-coefficient function difficult. 展开更多
关键词 weighing lysimeter EVAPOTRANSPIRATION crop coefficient water use efficiency COTTON
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Weighing In
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作者 Li Yifan 《Beijing Review》 2019年第39期38-39,共2页
Innovation reinvigorates a time-honored compressor factory Less than a year after he started working at the Shenyang Blower Works Factory,the predecessor of the Shenyang Blower Works Group(SBW),Wang Chuanghua was assi... Innovation reinvigorates a time-honored compressor factory Less than a year after he started working at the Shenyang Blower Works Factory,the predecessor of the Shenyang Blower Works Group(SBW),Wang Chuanghua was assigned a task in May 1992 to design two compressors with a pressure of 160 kg for a national-level chemical fertilizer project. 展开更多
关键词 SBW weighing In
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Weighing In on City Planning—Could smart urban design keep people fit and trim ?
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作者 Ben Harder 陈莉 《科技英语学习》 2007年第3期28-29,共2页
城市的规划布局对居民健康的影响究竟有多大?尤其对于爱散步的人来说,附近有些小店或是便利食品店会鼓励他们多走路,而一些现代化社区将商店、饭馆和其他生活设施集中在大型购物休闲中心内,反而打消了人们在附近走走顺便吃顿饭买点小东... 城市的规划布局对居民健康的影响究竟有多大?尤其对于爱散步的人来说,附近有些小店或是便利食品店会鼓励他们多走路,而一些现代化社区将商店、饭馆和其他生活设施集中在大型购物休闲中心内,反而打消了人们在附近走走顺便吃顿饭买点小东西的念头。如此说来,城市规划的“好看”和人们体型的好看与否还真是息息相关。 展开更多
关键词 In weighing In on City Planning Could smart urban design keep people fit and trim
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Determination of groundwater potential distribution in Kulfo-Hare watershed through integration of GIS, remote sensing, and AHP in Southern Ethiopia
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作者 Edmealem Temesgen Demelash Wendmagegnehu Goshime Destaw Akili 《Journal of Groundwater Science and Engineering》 2023年第3期249-262,共14页
Identification of groundwater potential areas(GPA)is important in regions facing surface water scarcity,as it assists in effective planning and utilization of groundwater for various purposes.This study employs the me... Identification of groundwater potential areas(GPA)is important in regions facing surface water scarcity,as it assists in effective planning and utilization of groundwater for various purposes.This study employs the methods of remote sensing(RS),geographic information system(GIS)model,and analytical hierarchy process(AHP),multi-criteria decision analysis(MCDA)to locate and map the prospective groundwater areas in the Kulfo-Hare watershed.Seven significant groundwater influencing factors were selected for the determination of groundwater potential in the area:Geology,land use/land cover(LULC),soil,rainfall,slope,drainage density,and lineament density.By applying a five-class classification scheme(very low,low,moderate,high,and very high),the GIS models were used to define the distribution of groundwater potential areas in terms of area coverage(km^(2)),percentage and mapping.The results show that the groundwater potential(GWP)distribution in the research region is as follows:9.7%(6035.9 ha)classified as very high GWP,29.6%(18606 ha)classified as high,24.5%(15245 ha)classified as moderate,18.1%(11431 ha)as low and 18.1%(11492 ha)very low GWP,on the basis of the weighted overlay evaluation.Although a few regions are identifies as extremely low GWP,most of the study area is characterized by very high to moderate GWP.These findings provide valuable insight for sustainable groundwater planning by the government bodies,decision-makers,and private sectors. 展开更多
关键词 Groundwater potential zone Multi-criteria decision Pairwise NORMALIZATION Weighed overlay analysis
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Validation of the effects of temperature simulated by multi-model ensemble and prediction of mean temperature changes for the next three decades in China
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作者 Ke Liu Jie Pan +1 位作者 ShengCai Tao YinLong Xu 《Research in Cold and Arid Regions》 2012年第1期56-64,共9页
Using series of daily average temperature observations over the period of 1961-1999 of 701 meteorological stations in China, and simulated results of 20 global climate models (such as BCCR_BCM2.0, CGCM3T47) during t... Using series of daily average temperature observations over the period of 1961-1999 of 701 meteorological stations in China, and simulated results of 20 global climate models (such as BCCR_BCM2.0, CGCM3T47) during the same period as the observation, we validate and analyze the simulated results of the models by using three factor statistical method, achieve the results of mul- ti-model ensemble, test and verify the results of multi-model ensemble by using the observation data during the period of 1991-1999. Finally, we analyze changes of the annual mean temperature result of multi-mode ensemble prediction for the period of 2011-2040 under the emission scenarios A2, A1B and B 1. Analyzed results show that: (1) Global climate models can repro- duce Chinese regional spatial distribution of annual mean temperature, especially in low latitudes and eastern China. (2) With the factor of the trend of annual mean temperature changes in reference period, there is an obvious bias between the model and the observation. (3) Testing the result of multi-model ensemble during the period of 1991-1999, we can simulate the trend of temper- ature increase. Compared to observation, the result of different weighing multi-model ensemble prediction is better than the same weighing ensemble. (4) For the period of 20ll-2040, the growth of the annual mean temperature in China, which results from multi-mode ensemble prediction, is above 1℃. In the spatial distribution of annual mean temperature, under the emission scenarios of A2, A1B and B 1, the trend of growth in South China region is the smallest, the increment is less than or equals to 0.8℃; the trends in the northwestern region and south of the Qinghai-Tibet Plateau are the largest, the increment is more than 1℃. 展开更多
关键词 global climate model different weighing multi-model ensemble same weighing multi-model ensemble wanning
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超高温超高密度有机盐钻井液技术研究 被引量:14
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作者 艾贵成 田效山 +2 位作者 兰祖权 王卫国 沈科 《西部探矿工程》 CAS 2010年第9期47-49,共3页
为解决费尔干纳盆地深部井段抗高温高密度钻井液技术难题,开发出了抗温220℃、密度2.60~3.00g/cm^3的有机盐钻井液技术,并进行了抗温、抗污染、抑制、储层保护、腐蚀性和环保能力等综合性能评价。实验表明:在密度达3.00g/cm^3... 为解决费尔干纳盆地深部井段抗高温高密度钻井液技术难题,开发出了抗温220℃、密度2.60~3.00g/cm^3的有机盐钻井液技术,并进行了抗温、抗污染、抑制、储层保护、腐蚀性和环保能力等综合性能评价。实验表明:在密度达3.00g/cm^3时,固相含量低于50%,滤饼摩阻系数小于0.20,具有良好的流动性和润滑防卡能力,较好地解决了加重材料的沉降和过饱和盐水的结晶问题。根据已钻井的经验,总结出了现场超高温超高密度有机盐钻井液的维护处理事项,为钻探作业的顺利开展提供了技术支撑。 展开更多
关键词 高密度 Weigh有机盐 有机盐钻井液 抗高温 润滑防卡
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A proposed surface resistance model for the Penman-Monteith formula to estimate evapotranspiration in a solar greenhouse 被引量:12
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作者 GONG Xuewen LIU Hao +6 位作者 SUN Jingsheng GAO Yang ZHANG Xiaoxian Shiva K JHA ZHANG Hao MA Xiaojian WANG Wanning 《Journal of Arid Land》 SCIE CSCD 2017年第4期530-546,共17页
Greenhousing is a technique to bridge season gap in vegetable production and has been widely used worldwide. Calculation of water requirement of crops grown in greenhouse and determination of their irrigation schedule... Greenhousing is a technique to bridge season gap in vegetable production and has been widely used worldwide. Calculation of water requirement of crops grown in greenhouse and determination of their irrigation schedules in arid and semi-arid regions are essential for greenhouse maintenance and have thus attracted increased attention over the past decades. The most common method used in the literature to estimate crop evapotranspiration(ET) is the Penman-Monteith(PM) formula. When applied to greenhouse, however, it often uses canopy resistance instead of surface resistance. It is understood that the surface resistance in greenhouse is the result of a combined effect of canopy restriction and soil-surface restriction to water vapor flow, and the relative dominance of one restriction over another depends on crop canopy. In this paper, we developed a surface resistance model in a way similar to two parallel resistances in an electrical circuit to account for both restrictions. Also, considering that wind speed in greenhouse is normally rather small, we compared three methods available in the literature to calculate the aerodynamic resistance, which are the r_a^1 method proposed by Perrier(1975a, b), the r_a^2 method proposed by Thom and Oliver(1977), and the r_a^3 method proposed by Zhang and Lemeu(1992). We validated the model against ET of tomatoes in a greenhouse measured from sap flow system combined with micro-lysimeter in 2015 and with weighing lysimeter in 2016. The results showed that the proposed surface resistance model improved the accuracy of the PM model, especially when the leaf area index was low and the greenhouse was being irrigated. We also found that the aerodynamic resistance calculated from the r_a^1 and r_a^3 methods is applicable to the greenhouse although the latter is slightly more accurate than the former. The proposed surface resistance model, together with the r_a^3 method for aerodynamic resistance, offers an improved approach to estimate ET in greenhouse using the PM formula. 展开更多
关键词 canopy resistance surface resistance aerodynamic resistance sap flow system micro-lysimeter weighing lysimeter
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无固相试井工作液室内研究 被引量:1
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作者 张鹏 郑力会 +2 位作者 张立波 张新海 田梅 《石油地质与工程》 CAS 2009年第1期118-119,122,共3页
根据有机盐水溶性加重剂Weigh2在复杂地层钻井、完井作业中的特点,通过优选黄原胶XC作为流型调节剂、改性抗温淀粉DFD-140和油溶性树脂暂堵剂实验,研制出三套有机盐Weigh2无固相试井工作液。该工作液性能稳定、密度可调、具有较好的固... 根据有机盐水溶性加重剂Weigh2在复杂地层钻井、完井作业中的特点,通过优选黄原胶XC作为流型调节剂、改性抗温淀粉DFD-140和油溶性树脂暂堵剂实验,研制出三套有机盐Weigh2无固相试井工作液。该工作液性能稳定、密度可调、具有较好的固相携带能力,便于充分洗井;其流变性、API和HTHP滤失量均能满足试井施工作业要求。 展开更多
关键词 Weigh2 无固相 试井工作液 钻井完井作业
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