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Systematic analysis and modeling of the FLASH sparing effect as a function of dose and dose rate
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作者 Qi-Bin Fu Yan Zhang +3 位作者 Yu-Cheng Wang Tu-Chen Huang Hong-Yu Zhu Xiao-Wu Deng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期51-58,共8页
Ultrahigh-dose-rate radiotherapy(FLASH-RT)is a revolutionary radiotherapy technology that can spare normal tissues without compromising tumor control.Although qualitative experimental results have been reported,quanti... Ultrahigh-dose-rate radiotherapy(FLASH-RT)is a revolutionary radiotherapy technology that can spare normal tissues without compromising tumor control.Although qualitative experimental results have been reported,quantitative and systematic analysis of data is necessary.Particularly,the FLASH effect response model to the dose or dose rate is still unclear.This study investigated the relationships between the FLASH effect and experimental parameters,such as dose,dose rate,and other factors by analyzing published in vivo experimental data from animal models.The data were modeled based on logistic regression analysis using the sigmoid function.The model was evaluated using prediction accuracy,receiver operating characteristic(ROC)curve,and area under the ROC curve.Results showed that the FLASH effect was closely related to the dose,mean dose rate,tissue type,and corresponding biological endpoints.The dose rate corresponding to a 50% probability of triggering cognitive protection in the brain was 45 Gy s^(-1).The dose rate corresponding to a 50% probability of triggering intestinal crypt survival and regeneration was 140 Gy s^(-1).For the skin toxicity effect,the dose corresponding to a 50% probability of triggering the FLASH effect was 24 Gy.This study helps to characterize the conditions underlying the FLASH effect and provides important information for optimizing experiments. 展开更多
关键词 FLASH radiotherapy Sparing effect Systematic analysis Dose rate DOSE Biological endpoints
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Analysis of sensitivity to hydrate blockage risk in natural gas gathering pipeline
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作者 Ao-Yang Zhang Meng Cai +4 位作者 Na Wei Hai-Tao Li Chao Zhang Jun Pei Xin-Wei Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2723-2733,共11页
During the operational process of natural gas gathering and transmission pipelines,the formation of hydrates is highly probable,leading to uncontrolled movement and aggregation of hydrates.The continuous migration and... During the operational process of natural gas gathering and transmission pipelines,the formation of hydrates is highly probable,leading to uncontrolled movement and aggregation of hydrates.The continuous migration and accumulation of hydrates further contribute to the obstruction of natural gas pipelines,resulting in production reduction,shutdowns,and pressure build-ups.Consequently,a cascade of risks is prone to occur.To address this issue,this study focuses on the operational process of natural gas gathering and transmission pipelines,where a comprehensive framework is established.This framework includes theoretical models for pipeline temperature distribution,pipeline pressure distribution,multiphase flow within the pipeline,hydrate blockage,and numerical solution methods.By analyzing the influence of inlet temperature,inlet pressure,and terminal pressure on hydrate formation within the pipeline,the sensitivity patterns of hydrate blockage risks are derived.The research indicates that reducing inlet pressure and terminal pressure could lead to a decreased maximum hydrate formation rate,potentially mitigating pipeline blockage during natural gas transportation.Furthermore,an increase in inlet temperature and terminal pressure,and a decrease in inlet pressure,results in a displacement of the most probable location for hydrate blockage towards the terminal station.However,it is crucial to note that operating under low-pressure conditions significantly elevates energy consumption within the gathering system,contradicting the operational goal of energy efficiency and reduction of energy consumption.Consequently,for high-pressure gathering pipelines,measures such as raising the inlet temperature or employing inhibitors,electrical heat tracing,and thermal insulation should be adopted to prevent hydrate formation during natural gas transportation.Moreover,considering abnormal conditions such as gas well production and pipeline network shutdowns,which could potentially trigger hydrate formation,the installation of methanol injection connectors remains necessary to ensure production safety. 展开更多
关键词 Natural gas hydrates Gathering pipeline Temperature variation Hydrate formation rate Sensitivity analysis
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Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron
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作者 De-quan Shi Ze-yu Liu +1 位作者 Gui-li Gao Yi-cheng Feng 《China Foundry》 SCIE EI CAS CSCD 2024年第1期91-100,共10页
Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements af... Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements affecting the solidification of molten iron.In this study,FeSi75 was added in one chamber of the dual-chamber sample cup,and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were investigated.The results show that with the increase of FeSi75,the start temperature of austenite formation TALfirstly decreases and then increases,but the start temperature of eutectic growth TSEF,the lowest eutectic temperature TEU,temperature at maximum eutectic reaction rate TEM,and highest eutectic temperature TERkeep always an increase.The temperature at final solidification point TEShas little change.The FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation,and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher one.According to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.%FeSi75 additive in one chamber,the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these curves.The time differenceΔtERcorresponding to the highest eutectic temperature TERhas a closer relationship with the vermiculating rate,and a parabolic regression curve between the time differenceΔtERand vermiculating rateηhas been obtained within the range of 65%to 95%,which is suitable for the qualified melt. 展开更多
关键词 FeSi75 additive characteristic value vermiculating rate thermal analysis compacted graphite iron
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Rate transient analysis methods for water-producing gas wells in tight reservoirs with mobile water
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作者 Qingyan Yu Ying Jia +2 位作者 Pengcheng Liu Xiangyang Hu Shengye Hao 《Energy Geoscience》 EI 2024年第1期311-320,共10页
Tight gas reservoirs with mobile water exhibit multi-phase flow and high stress sensitivity.Accurately analyzing the reservoir and well parameters using conventional single-phase rate transient analysis methods proves... Tight gas reservoirs with mobile water exhibit multi-phase flow and high stress sensitivity.Accurately analyzing the reservoir and well parameters using conventional single-phase rate transient analysis methods proves challenging.This study introduces novel rate transient analysis methods incorporating evaluation processes based on the conventional flowing material balance method and the Blasingame type-curve method to examine fractured gas wells producing water.By positing a gas-water two-phase equivalent homogenous phase that considers characteristics of mobile water,gas,and high stress sensitivity,the conventional single-phase rate transient analysis methods can be applied by integrating the phase's characteristics and defining the phase's normalized parameters and material balance pseudotime.The rate transient analysis methods based on the equivalent homogenous phase can be used to quantitatively assess the parameters of wells and gas reservoirs,such as original gas-in-place,fracture half-length,reservoir permeability,and well drainage radius.This facilitates the analysis of production dynamics of fractured wells and well-controlled areas,subsequently aiding in locating residual gas and guiding the configuration of well patterns.The specific evaluation processes are detailed.Additionally,a numerical simulation mechanism model was constructed to verify the reliability of the developed methods.The methods introduced have been successfully implemented in field water-producing gas wells within tight gas reservoirs containing mobile water. 展开更多
关键词 Gas reservoirs with mobile water Gas-water two phase flow High stress sensitivity Equivalent homogenous phase rate transient analysis
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A comprehensive review of heart rate variability as an indicator in the regulation of the autonomic nervous system by acupuncture:a bibliometric analysis
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作者 Yi-Feng Shen Kun Zhu +4 位作者 Jun-Long Zhu Xiao-Peng Huang De-Gui Chang Yao-Dong You Dong-Dong Yang 《Integrative Medicine Discovery》 2024年第14期1-14,共14页
This study sought to conduct a bibliometric analysis of acupuncture studies focusing on heart rate variability(HRV)and to investigate the correlation between various acupoints and their effects on HRV by utilizing ass... This study sought to conduct a bibliometric analysis of acupuncture studies focusing on heart rate variability(HRV)and to investigate the correlation between various acupoints and their effects on HRV by utilizing association rule mining and network analysis.A total of 536 publications on the topic of acupuncture studies based on HRV.The disease keyword analysis revealed that HRV-related acupuncture studies were mainly related to pain,inflammation,emotional disorders,gastrointestinal function,and hypertension.A separate analysis was conducted on acupuncture prescriptions,and Neiguan(PC6)and Zusanli(ST36)were the most frequently used acupoints.The core acupoints for HRV regulation were identified as PC6,ST36,Shenmen(HT7),Hegu(LI4),Sanyinjiao(SP6),Jianshi(PC5),Taichong(LR3),Quchi(LI11),Guanyuan(CV4),Baihui(GV20),and Taixi(KI3).Additionally,the research encompassed 46 reports on acupuncture animal experiments conducted on HRV,with ST36 being the most frequently utilized acupoint.The research presented in this study offers valuable insights into the global research trend and hotspots in acupuncture-based HRV studies,as well as identifying frequently used combinations of acupoints.The findings may be helpful for further research in this field and provide valuable information about the potential use of acupuncture for improving HRV in both humans and animals. 展开更多
关键词 heart rate variability ACUPUNCTURE autonomous nerves system bibliometric analysis data mining
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Genetic dissection of the grain-filling rate and related traits through linkage analysis and genome-wide association study in bread wheat 被引量:2
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作者 YU Hai-xia DUAN Xi-xian +12 位作者 SUN Ai-qing SUN Xiao-xiao ZHANG Jing-juan SUN Hua-qing SUN Yan-yan NING Tang-yuan TIAN Ji-chun WANG Dong-xue LI Hao FAN Ke-xin WANG Ai-ping MA Wu-jun CHEN Jian-sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第10期2805-2817,共13页
Wheat grain yield is generally sink-limited during grain filling.The grain-filling rate(GFR)plays a vital role but is poorly studied due to the difficulty of phenotype surveys.This study explored the grain-filling tra... Wheat grain yield is generally sink-limited during grain filling.The grain-filling rate(GFR)plays a vital role but is poorly studied due to the difficulty of phenotype surveys.This study explored the grain-filling traits in a recombinant inbred population and wheat collection using two highly saturated genetic maps for linkage analysis and genome-wide association study(GWAS).Seventeen stable additive quantitative trait loci(QTLs)were identified on chromosomes 1B,4B,and 5A.The linkage interval between IWB19555 and IWB56078 showed pleiotropic effects on GFR_(1),GFR_(max),kernel length(KL),kernel width(KW),kernel thickness(KT),and thousand kernel weight(TKW),with the phenotypic variation explained(PVE)ranging from 13.38%(KW)to 33.69%(TKW).198 significant marker-trait associations(MTAs)were distributed across most chromosomes except for 3D and 4D.The major associated sites for GFR included IWB44469(11.27%),IWB8156(12.56%)and IWB24812(14.46%).Linkage analysis suggested that IWB35850,identified through GWAS,was located in approximately the same region as QGFR_(max)2B.3-11,where two high-confidence candidate genes were present.Two important grain weight(GW)-related QTLs colocalized with grain-filling QTLs.The findings contribute to understanding the genetic architecture of the GFR and provide a basic approach to predict candidate genes for grain yield trait QTLs. 展开更多
关键词 WHEAT grain-filling rate linkage analysis genome-wide association study
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Application of thermodynamics-based rate-dependent constitutive models of concrete in the seismic analysis of concrete dams 被引量:1
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作者 Leng Fei Lin Gao 《Water Science and Engineering》 EI CAS 2008年第3期54-64,共11页
This paper discusses the seismic analysis of concrete dams with consideration of material nonlinearity. Based on a consistent rate-dependent model and two thermodynamics-based models, two thermodynamics-based rate-dep... This paper discusses the seismic analysis of concrete dams with consideration of material nonlinearity. Based on a consistent rate-dependent model and two thermodynamics-based models, two thermodynamics-based rate-dependent constitutive models were developed with consideration of the influence of the strain rate. They can describe the dynamic behavior of concrete and be applied to nonlinear seismic analysis of concrete dams taking into account the rate sensitivity of concrete. With the two models, a nonlinear analysis of the seismic response of the Koyna Gravity Dam and the Dagangshan Arch Dam was conducted. The results were compared with those of a linear elastic model and two rate-independent thermodynamics-based constitutive models, and the influences of constitutive models and strain rate on the seismic response of concrete dams were discussed. It can be concluded from the analysis that, during seismic response, the tensile stress is the control stress in the design and seismic safety evaluation of concrete dams. In different models, the plastic strain and plastic strain rate of concrete dams show a similar distribution. When the influence of the strain rate is considered, the maximum plastic strain and plastic strain rate decrease. 展开更多
关键词 CONCRETE constitutive model rate dependency concrete dam NONLINEARITY seismic analysis
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ACCURACY ANALYSIS OF PASSIVE LOCATION SYSTEM WITH PHASE DIFFERENCE RATE MEASUREMENT 被引量:1
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作者 邓新蒲 姜文利 周一宇 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2000年第4期222-227,共6页
The conventional mono-station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement-rate (derivative) of phase diff... The conventional mono-station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement-rate (derivative) of phase difference from a two-element antenna array (interferometer) is introduced, accuracy of a passive location system with this measurement and directions of arrival (DOA) is analyzed, and the Cramer-Rao bound of location error of this system for 3D location is examined by simulations. 展开更多
关键词 passive location phase difference rate location accuracy analysis INTERFEROMETER
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Well interference evaluation considering complex fracture networks through pressure and rate transient analysis in unconventional reservoirs 被引量:2
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作者 Jia-Zheng Qin Qian-Hu Zhong +2 位作者 Yong Tang Wei Yu Kamy Sepehrnoori 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期337-349,共13页
Severe well interference through complex fracture networks(CFNs)can be observed among multi-well pads in low permeability reservoirs.The well interference analysis between multi-fractured horizontal wells(MFHWs)is vit... Severe well interference through complex fracture networks(CFNs)can be observed among multi-well pads in low permeability reservoirs.The well interference analysis between multi-fractured horizontal wells(MFHWs)is vitally important for reservoir effective development.Well interference has been historically investigated by pressure transient analysis,while it has shown that rate transient analysis has great potential in well interference diagnosis.However,the impact of complex fracture networks(CFNs)on rate transient behavior of parent well and child well in unconventional reservoirs is still not clear.To further investigate,this paper develops an integrated approach combining pressure and rate transient analysis for well interference diagnosis considering CFNs.To perform multi-well simulation considering CFNs,non-intrusive embedded discrete fracture model approach was applied for coupling fracture with reservoir models.The impact of CFN including natural fractures and frac-hits on pressure and rate transient behavior in multi-well system was investigated.On a logelog plot,interference flow and compound linear flow are two new flow regimes caused by nearby producers.When both NFs and frac-hits are present in the reservoir,frac-hits have a greater impact on well#1 which contains frac-hits,and NFs have greater impact on well#3 which does not have frac-hits.For all well producing circumstances,it might be challenging to see divergence during pseudosteady state flow brought on by frac-hits on the logelog plot.Besides,when NFs occur,reservoir depletion becomes noticeable in comparison to frac-hits in pressure distribution.Application of this integrated approach demonstrates that it works well to characterize the well interference among different multi-fractured horizontal wells in a well pad.Better reservoir evaluation can be acquired based on the new features observed in the novel model,demonstrating the practicability of the proposed approach.The findings of this study can help for better evaluating well interference degree in multi-well systems combing PTA and RTA,which can reduce the uncertainty and improve the accuracy of the well interference analysis based on both field pressure and rate data. 展开更多
关键词 Well interference Numerical rate transient analysis Numerical pressure transient analysis Complex fracture networks Embedded discrete fracture model
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Machine Learning-based USD/PKR Exchange Rate Forecasting Using Sentiment Analysis of Twitter Data 被引量:1
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作者 Samreen Naeem Wali Khan Mashwani +4 位作者 Aqib Ali M.Irfan Uddin Marwan Mahmoud Farrukh Jamal Christophe Chesneau 《Computers, Materials & Continua》 SCIE EI 2021年第6期3451-3461,共11页
This study proposes an approach based on machine learning to forecast currency exchange rates by applying sentiment analysis to messages on Twitter(called tweets).A dataset of the exchange rates between the United Sta... This study proposes an approach based on machine learning to forecast currency exchange rates by applying sentiment analysis to messages on Twitter(called tweets).A dataset of the exchange rates between the United States Dollar(USD)and the Pakistani Rupee(PKR)was formed by collecting information from a forex website as well as a collection of tweets from the business community in Pakistan containing finance-related words.The dataset was collected in raw form,and was subjected to natural language processing by way of data preprocessing.Response variable labeling was then applied to the standardized dataset,where the response variables were divided into two classes:“1”indicated an increase in the exchange rate and“−1”indicated a decrease in it.To better represent the dataset,we used linear discriminant analysis and principal component analysis to visualize the data in three-dimensional vector space.Clusters that were obtained using a sampling approach were then used for data optimization.Five machine learning classifiers—the simple logistic classifier,the random forest,bagging,naïve Bayes,and the support vector machine—were applied to the optimized dataset.The results show that the simple logistic classifier yielded the highest accuracy of 82.14%for the USD and the PKR exchange rates forecasting. 展开更多
关键词 Machine learning exchange rate sentiment analysis linear discriminant analysis principal component analysis simple logistic
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Modeling,Simulation,and Risk Analysis of Battery Energy Storage Systems in New Energy Grid Integration Scenarios
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作者 Xiaohui Ye Fucheng Tan +4 位作者 Xinli Song Hanyang Dai Xia Li Shixia Mu Shaohang Hao 《Energy Engineering》 EI 2024年第12期3689-3710,共22页
Energy storage batteries can smooth the volatility of renewable energy sources.The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy s... Energy storage batteries can smooth the volatility of renewable energy sources.The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy storage system(BESS).However,the current modeling of grid-connected BESS is overly simplistic,typically only considering state of charge(SOC)and power constraints.Detailed lithium(Li)-ion battery cell models are computationally intensive and impractical for real-time applications and may not be suitable for power grid operating conditions.Additionally,there is a lack of real-time batteries risk assessment frameworks.To address these issues,in this study,we establish a thermal-electric-performance(TEP)coupling model based on a multitime scale BESS model,incorporating the electrical and thermal characteristics of Li-ion batteries along with their performance degradation to achieve detailed simulation of grid-connected BESS.Additionally,considering the operating characteristics of energy storage batteries and electrical and thermal abuse factors,we developed a battery pack operational riskmodel,which takes into account SOCand charge-discharge rate(Cr),using amodified failure rate to represent the BESS risk.By integrating detailed simulation of energy storage with predictive failure risk analysis,we obtained a detailed model for BESS risk analysis.This model offers a multi-time scale integrated simulation that spans month-level energy storage simulation times,day-level performance degradation,minutescale failure rate,and second-level BESS characteristics.It offers a critical tool for the study of BESS.Finally,the performance and risk of energy storage batteries under three scenarios—microgrid energy storage,wind power smoothing,and power grid failure response—are simulated,achieving a real-time state-dependent operational risk analysis of the BESS. 展开更多
关键词 Grid-connected battery energy storage system thermal-electric-performance coupling model operational risk model failure rate risk analysis
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Modelling and Analysis of Bacteria Dependent Infectious Diseases with Variable Contact Rates 被引量:1
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作者 J.B.Shukla Shikha Singh +1 位作者 Jitendra Singh Sunil Kumar Sharma 《Computers, Materials & Continua》 SCIE EI 2021年第8期1859-1875,共17页
In this research,we proposed a non-linear SIS model to study the effect of variable interaction rates and non-emigrating population of the human habitat on the spread of bacteria-infected diseases.It assumed that the ... In this research,we proposed a non-linear SIS model to study the effect of variable interaction rates and non-emigrating population of the human habitat on the spread of bacteria-infected diseases.It assumed that the growth of bacteria is logistic with an intrinsic growth rate is a linear function of infectives.In this model,we assume that contact rates between susceptibles and infectives as well as between susceptibles and bacteria depend on the density of the non-emigrating population and the total population of the habitat.The stability theory has been analyzed to analyzed to study the crucial role played by bacteria in the increased spread of an infectious disease.It is shown that as the density of non-emigrating population increases,the spread of an infectious disease increases.It is shown further that as the emigration increases,the spread of the disease decreases in both the cases of contact mentioned above rates,but this spread increases as these contact rates increase.It suggested that the control of bacteria in the human habitat is very useful to decrease the spread of an infectious disease.These results are confirmed by numerical simulation. 展开更多
关键词 Mathematical modelling density dependent contact rates stability analysis
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Prediction of cavity growth rate during underground coal gasification using multiple regression analysis 被引量:8
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作者 Mehdi Najafi Seyed Mohammad Esmaiel Jalali +1 位作者 Reza KhaloKakaie Farrokh Forouhandeh 《International Journal of Coal Science & Technology》 EI 2015年第4期318-324,共7页
During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by... During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by controllable (operation pressure, gasification time, geometry of UCG panel) and uncontrollable (coal seam properties) factors. The CGR is usually predicted by mathematical models and laboratory experiments, which are time consuming, cumbersome and expensive. In this paper, a new simple model for CGR is developed using non-linear regression analysis, based on data from 1 l UCG field trials. The empirical model compares satisfactorily with Perkins model and can reliably predict CGR. 展开更多
关键词 Underground coal gasification (UCG) - Cavity growth rate . Multiple regression analysis ~ Empirical model
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A Research for Regional Contribution Rate of Internal Source and External Source of PM_(2.5) Based on Set Pair Analysis Method 被引量:1
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作者 Zhou Yejing Zhou Jingxuan Xiao Renbin 《Meteorological and Environmental Research》 CAS 2016年第2期36-40,44,共6页
A problem of the air pollution control in China is getting to know a regional contribution rate of internal and external source of PM2.5. In this paper,Set Pair Analysis( SPA) method is proposed to calculate the con... A problem of the air pollution control in China is getting to know a regional contribution rate of internal and external source of PM2.5. In this paper,Set Pair Analysis( SPA) method is proposed to calculate the contribution rate of PM2.5in Dongguan City. Due to geographic,meteorological factors and the low concentration of air pollutants in Qingxi area,the PM2.5in this place is mainly contributed by the regional transport of air pollutants from other inside areas of Dongguan,and less affected by the outside of Dongguan. So the concentration of PM2.5in Qingxi area can reflect the Dongguan's basic background concentration of PM2.5. On the basis of the basic background concentration,firstly the concentration of each pollutant components is divided into the internal part and the mixed part. Secondly using the source apportionment samples of five monitoring sites in Dongguan we can respectively construct a sample set A and an evaluation set B. Thirdly the SPA is operated onto the mixed part in terms of set B.At last the connection degree between the concentration of each pollutant components and external source and internal source will be calculated,that is the contribution rate. The research reveals that the contribution rate of internal source and external source of PM2.5in Dongguan City is 83%and 17% respectively,which roughly met expectations. This method is simple and effective and it can provide a reference for the government taking reduction measures to control PM2.5pollutants emission. 展开更多
关键词 Set Pair analysis Connection degree PM2.5 Internal source External source Contribution rate
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Design of a Technology Verification Platform for Space Electromagnetic Interference Signal Testing and Analysis
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作者 Qi Liu Huiwen Du +1 位作者 Chao Zhang Yazhou Zhang 《Journal of Electronic Research and Application》 2024年第5期72-79,共8页
This paper designs a space electromagnetic interference signal test and analysis technology verification platform.The article firstly introduces the general scheme of the technical verification platform and then descr... This paper designs a space electromagnetic interference signal test and analysis technology verification platform.The article firstly introduces the general scheme of the technical verification platform and then describes each component unit of the hardware and the overall structure of the software in detail.The platform can achieve a 10 MHz~50 GHz working frequency band,1.2 GHz acquisition and real-time recording bandwidth,6 GB/s recording rate,and 12 TB recording capacity. 展开更多
关键词 Real-time recording bandwidth Recording rate Recording capacity Playback analysis
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QTL analysis of leaf photosynthetic rate and related physiological traits in rice(Oryza sativa L.) 被引量:3
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作者 TENG Sheng, QIAN Qian, ZENG Dali, Yasufumi Kunihiro, Hiroshi Fujimoto, HUANG Daman, and ZHU Lihuang, Key Lab for Rice Biology, CNRRI, Hangzhou 310006 Inst of Genetics and Development Biology, the Chinese Academy of Sciences, Beijing 100101 +1 位作者 College of Life Sci, Zhejiang Univ, Hangzhou 310029, China Japan International Res Center for Agri Sci, Tsukuba, Japan 《Chinese Rice Research Newsletter》 2002年第3期4-6,共3页
Photosynthesis is one of the most important factors that influence the biomass and yield. Recently, more attention has been paid to genetic study on rice photosynthesis and rice breeding for the physiological traits r... Photosynthesis is one of the most important factors that influence the biomass and yield. Recently, more attention has been paid to genetic study on rice photosynthesis and rice breeding for the physiological traits related to high efficient photosynthesis. Chlorophyll content, stomatal resistance, and transpiration rate were very important physiological traits related to photosynthesis. But until now, no genetic study on these traits has been reported. A DH population derived from anther culture of ZYQ8/JX17, a typical indica/japonica hybrid was developed, 展开更多
关键词 rate DH Oryza sativa L QTL analysis of leaf photosynthetic rate and related physiological traits in rice
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Elemental analysis of copper alloy by high repetition rate LA-SIBS using compact fiber spectrometer
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作者 Xiaoyong HE Runhua LI Fujuan WANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期40-45,共6页
High repetition rate laser-ablation spark-induced breakdown spectroscopy(HRR LA-SIBS) was first used to analyze trace elements in copper alloy samples. The 1064 nm output of an acoustooptically Q-switched Nd:YAG laser... High repetition rate laser-ablation spark-induced breakdown spectroscopy(HRR LA-SIBS) was first used to analyze trace elements in copper alloy samples. The 1064 nm output of an acoustooptically Q-switched Nd:YAG laser operated at a pulse repetition rate of 1 kHz was utilized to ablate copper alloy and to form original plasma, spark-discharge was applied to further breakdown the ablated samples and enhance the emission of the laser-induced plasma. A compact multichannel fiber spectrometer was used to analyze the plasma emission under nongated operation mode. Under the assistance of high repetition rate spark discharge, the plasma emission was able to be improved significantly. The determined limits of the detection of lead and aluminum were 15.5 ppm and 1.9 ppm by HRR LA-SIBS, respectively, which were 11 and 6 folds better than that determined by HRR LIBS under the same laser-ablation condition. This work demonstrates the feasibility of using fiber spectrometer to analyze plasma emission under non-gated operation mode and the possibility of building a portable HRR LA-SIBS system for rapid elemental analysis of copper alloys and other solid samples. 展开更多
关键词 high REPETITION rate LASER-ABLATION spark-induced BREAKDOWN spectroscopy copper alloy rapid analysis
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Study on Differential Rate Kinetics Analysis Based on the Substitution Reaction of Rare Earth-PHA with CyDTA
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作者 蔡汝秀 杨屹 +2 位作者 林智信 曾云鹗 王丽莎 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第4期300-305,共6页
The kinetic behaviours of the substitution reaction of rare earth-PHA with CyDTA were studied systemati- cally.The relationship between the rate constant and atomic number was discussed.The rate differentiation val- u... The kinetic behaviours of the substitution reaction of rare earth-PHA with CyDTA were studied systemati- cally.The relationship between the rate constant and atomic number was discussed.The rate differentiation val- ue R_d(R_d=lgk_(z+n)-lgk_z)was proposed to evaluate the possibility of differential kinetic analysis.The R_d value between the neighbouring lanthanide ions first increases and then decreases along with increasing atomic number, so that the middle and heavy rare earth mixture(such as Sm-Gd and Gd-Y)are ideal systems for the differential rate kinetic analysis. 展开更多
关键词 RE Differential rate kinetics analysis PHA (Polyhalogenated bisazo chromotropic acid derivants)
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L0 Regularization for the Estimation of Piecewise Constant Hazard Rates in Survival Analysis
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作者 Olivier Bouaziz Grégory Nuel 《Applied Mathematics》 2017年第3期377-394,共18页
In a survival analysis context, we suggest a new method to estimate the piecewise constant hazard rate model. The method provides an automatic procedure to find the number and location of cut points and to estimate th... In a survival analysis context, we suggest a new method to estimate the piecewise constant hazard rate model. The method provides an automatic procedure to find the number and location of cut points and to estimate the hazard on each cut interval. Estimation is performed through a penalized likelihood using an adaptive ridge procedure. A bootstrap procedure is proposed in order to derive valid statistical inference taking both into account the variability of the estimate and the variability in the choice of the cut points. The new method is applied both to simulated data and to the Mayo Clinic trial on primary biliary cirrhosis. The algorithm implementation is seen to work well and to be of practical relevance. 展开更多
关键词 Adaptive RIDGE Procedure HAZARD rate ESTIMATION Penalized LIKELIHOOD PIECEWISE CONSTANT HAZARD Survival analysis
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Infant Mortality Rate Statistic Method and Difference Analysis in China
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作者 Benfeng Du Yu Zhang 《Open Journal of Statistics》 2011年第3期236-243,共8页
Infant mortality rate (IMR) has been viewed as the vital index which can be used to measure the health level of a country or a district, and also can indirectly illustrate the economic development level of the country... Infant mortality rate (IMR) has been viewed as the vital index which can be used to measure the health level of a country or a district, and also can indirectly illustrate the economic development level of the country or district. In this paper, the authors 1) introduce three calculation methods of IMR and compare the differences among them;2) calculate the IMR using one method above, and find the IMRs recorded in China Population Statistic Yearbook (CPSY) from National Statistics Institute and in China Health Statistic Yearbook from Ministry of National Hygiene are both overestimated;3) point out three main reasons for this overestimation: firstly, confusion of methods of calculation and concepts, secondly, inconsistent statistical caliber among different yearbooks, thirdly, flaws within the registration system. 展开更多
关键词 INFANT MORTALITY rate Statistic METHOD DIFFERENCES analysis
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