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Research status of soil frost-heave theory and frost-heave prediction models
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作者 XiangDong Zhang ShengYang Feng 《Research in Cold and Arid Regions》 2010年第1期82-86,共5页
Soil frost heaving is a complex physical, mechanical, and chemical synthesis process. This paper summarizes the frost-heaving theory over half a century, including the capillary theory, the frozen-fringe theory, and t... Soil frost heaving is a complex physical, mechanical, and chemical synthesis process. This paper summarizes the frost-heaving theory over half a century, including the capillary theory, the frozen-fringe theory, and those achievements recently made by scholars. In this paper, we also discus researching achievements of the soil-prediction model during the past 40 years, including the water-dynamics model, the rigid-ice model, the segregation-potential model, and the thermo-dynamic model. This summary and discussion will enable readers to understand the latest direction of research; it also summarizes the development of frost-heave prediction models and their advantages and shortcomings. 展开更多
关键词 frost heaving theory frost heaving model research status
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“Flipped Classroom” Teaching Model Research: A Case Study of “Innovation and Entrepreneurship Education and Practice (Theory)”
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作者 Xiushu Zhao 《Open Journal of Applied Sciences》 2023年第11期2007-2013,共7页
The flipped classroom model differs significantly from the traditional classroom teaching model and offers numerous advantages. This article draws inspiration from the flipped classroom concept, using the “Innovation... The flipped classroom model differs significantly from the traditional classroom teaching model and offers numerous advantages. This article draws inspiration from the flipped classroom concept, using the “Innovation and Entrepreneurship Education and Practice (Theory)” course as an example to introduce the innovation and characteristics of the flipped classroom model: it is problem-oriented, addressing the “pain points” in teaching, motivating students towards “active learning,” and integrating diverse teaching methods. In the conclusion, the article proposed suggestions on the application of this model, encouraging teachers to summarize their teaching experiences, enhance their knowledge base, and foster students’ awareness of innovation and entrepreneurship. 展开更多
关键词 Flipped Classroom Teaching Model research Innovation and Entrepreneurship Education and Practice CASE
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Research on the New Model of Student Education Management in Vocational Colleges
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作者 Mingyuan Liu 《Journal of Contemporary Educational Research》 2023年第9期91-97,共7页
Vocational colleges are an important type of higher education in China.Higher vocational education aims to adapt to social needs and designs students’knowledge,ability,quality structure,and training plans based on th... Vocational colleges are an important type of higher education in China.Higher vocational education aims to adapt to social needs and designs students’knowledge,ability,quality structure,and training plans based on the cultivation of technical application skills.Emphasizing both theoretical teaching and practical training,graduates have the skills to work directly.At this stage,vocational education in China is in an important period of transformation and development.In order to better adapt to the rapid development of society,many vocational colleges have carried out management system reforms in student education management,with the aim of cultivating more high-quality and skilled talents that meet the needs of social development,and providing higher quality vocational education services for the country and society.In the process of physical education reform,due to regional and other factors,many reform models cannot adapt to the current situation of student education management in vocational colleges in the new era.Therefore,it is necessary to continuously explore new models suitable for vocational colleges.Based on the background of the physical education reform in vocational colleges,this article uses methods such as literature research and visits to analyze the current situation of education management in vocational colleges,the problems and possible reasons that exist in student education management in vocational colleges.This article discusses the possible new models of student education management in vocational colleges from the perspectives of repeated management methods,management concepts,management mechanisms,and evaluation systems,and elaborates on their new paths.Efforts are made to improve the management mode of student education in vocational colleges,innovate the management mechanism of vocational colleges,and actively explore the improvement of the management mode of student education in vocational colleges. 展开更多
关键词 Vocational colleges Educational management Model research
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Success rate of current human-derived gastric cancer organoids establishment and influencing factors:A systematic review and meta-analysis
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作者 Kai-Lin Jiang Xiang-Xiang Wang +5 位作者 Xue-Jiao Liu Li-Kun Guo Yong-Qi Chen Qing-Ling Jia Ke-Ming Yang Jiang-Hong Ling 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1626-1646,共21页
BACKGROUND Human-derived gastric cancer organoids(GCOs)are widely used in gastric cancer research;however,the culture success rate is generally low.AIM To explore the potential influencing factors,and the literature o... BACKGROUND Human-derived gastric cancer organoids(GCOs)are widely used in gastric cancer research;however,the culture success rate is generally low.AIM To explore the potential influencing factors,and the literature on successful culture rates of GCOs was reviewed using meta-analysis.METHODS PubMed,Web of Science,and EMBASE were searched for studies.Two trained researchers selected the studies and extracted data.STATA 17.0 software was used for meta-analysis of the incidence of each outcome event.The adjusted Methodological Index for Non-Randomized Studies scale was used to assess the quality of the included studies.Funnel plots and Egger’s test were used to detect publication bias.Subgroup analyses were conducted for sex,tissue source,histo-logical classification,and the pathological tumor-node-metastasis(pTNM)cancer staging system.RESULTS Eight studies with a pooled success rate of 66.6%were included.GCOs derived from women and men had success rates of 67%and 46.7%,respectively.GCOs from surgery or biopsy/endoscopic submucosal dissection showed success rates of 70.9%and 53.7%,respectively.GCOs of poorly-differentiated,moderately-differentiated and signet-ring cell cancer showed success rates of 64.6%,31%,and 32.7%,respectively.GCOs with pTNM stages I-II and III-IV showed success rates of 38.3%and 65.2%,respectively.Y-27632 and non-Y-27632 use showed success rates of 58.2%and 70%,respectively.GCOs generated with collagenase were more successful than those constructed with Liberase TH and TrypLE(72.1%vs 71%,respectively).EDTA digestion showed a 50%lower success rate than other methods(P=0.04).CONCLUSION GCO establishment rate is low and varies by sex,tissue source,histological type,and pTNM stage.Omitting Y-27632,and using Liberase TH,TrypLE,or collagenase yields greater success than EDTA. 展开更多
关键词 Gastric cancer organoids Human-derived organoids Gastric cancer Cell lines In vitro research models
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Risk assessment of high-speed railway CTC system based on improved game theory and cloud model
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作者 Yanhao Sun Tao Zhang +2 位作者 Shuxin Ding Zhiming Yuan Shengliang Yang 《Railway Sciences》 2024年第3期388-410,共23页
Purpose-In order to solve the problem of inaccurate calculation of index weights,subjectivity and uncertainty of index assessment in the risk assessment process,this study aims to propose a scientific and reasonable c... Purpose-In order to solve the problem of inaccurate calculation of index weights,subjectivity and uncertainty of index assessment in the risk assessment process,this study aims to propose a scientific and reasonable centralized traffic control(CTC)system risk assessment method.Design/methodologylapproach-First,system-theoretic process analysis(STPA)is used to conduct risk analysis on the CTC system and constructs risk assessment indexes based on this analysis.Then,to enhance the accuracy of weight calculation,the fuzzy analytical hierarchy process(FAHP),fuzzy decision-making trial and evaluation laboratory(FDEMATEL)and entropy weight method are employed to calculate the subjective weight,relative weight and objective weight of each index.These three types of weights are combined using game theory to obtain the combined weight for each index.To reduce subjectivity and uncertainty in the assessment process,the backward cloud generator method is utilized to obtain the numerical character(NC)of the cloud model for each index.The NCs of the indexes are then weighted to derive the comprehensive cloud for risk assessment of the CTC system.This cloud model is used to obtain the CTC system's comprehensive risk assessment.The model's similarity measurement method gauges the likeness between the comprehensive risk assessment cloud and the risk standard cloud.Finally,this process yields the risk assessment results for the CTC system.Findings-The cloud model can handle the subjectivity and fuzziness in the risk assessment process well.The cloud model-based risk assessment method was applied to the CTC system risk assessment of a railway group and achieved good results.Originality/value-This study provides a cloud model-based method for risk assessment of CTC systems,which accurately calculates the weight of risk indexes and uses cloud models to reduce uncertainty and subjectivity in the assessment,achieving effective risk assessment of CTC systems.It can provide a reference and theoretical basis for risk management of the CTC system. 展开更多
关键词 High-speed railway Centralized traffic control Risk assessment Game theory Cloud model Paper type research paper
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Artificial Intelligence Based Meteorological Parameter Forecasting for Optimizing Response of Nuclear Emergency Decision Support System
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作者 BILAL Ahmed Khan HASEEB ur Rehman +5 位作者 QAISAR Nadeem MUHAMMAD Ahmad Naveed Qureshi JAWARIA Ahad MUHAMMAD Naveed Akhtar AMJAD Farooq MASROOR Ahmad 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第10期2068-2076,共9页
This paper presents a novel artificial intelligence (AI) based approach to predict crucial meteorological parameters such as temperature,pressure,and wind speed,typically calculated from computationally intensive weat... This paper presents a novel artificial intelligence (AI) based approach to predict crucial meteorological parameters such as temperature,pressure,and wind speed,typically calculated from computationally intensive weather research and forecasting (WRF) model.Accurate meteorological data is indispensable for simulating the release of radioactive effluents,especially in dispersion modeling for nuclear emergency decision support systems.Simulation of meteorological conditions during nuclear emergencies using the conventional WRF model is very complex and time-consuming.Therefore,a new artificial neural network (ANN) based technique was proposed as a viable alternative for meteorological prediction.A multi-input multi-output neural network was trained using historical site-specific meteorological data to forecast the meteorological parameters.Comprehensive evaluation of this technique was conducted to test its performance in forecasting various parameters including atmospheric pressure,temperature,and wind speed components in both East-West and North-South directions.The performance of developed network was evaluated on an unknown dataset,and acquired results are within the acceptable range for all meteorological parameters.Results show that ANNs possess the capability to forecast meteorological parameters,such as temperature and pressure,at multiple spatial locations within a grid with high accuracy,utilizing input data from a single station.However,accuracy is slightly compromised when predicting wind speed components.Root mean square error (RMSE) was utilized to report the accuracy of predicted results,with values of 1.453℃for temperature,77 Pa for predicted pressure,1.058 m/s for the wind speed of U-component and 0.959 m/s for the wind speed of V-component.In conclusion,this approach offers a precise,efficient,and wellinformed method for administrative decision-making during nuclear emergencies. 展开更多
关键词 prediction of meteorological parameters weather research and forecasting model artificial neural networks nuclear emergency support system
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A STUDY OF THE INFLUENCE OF MICROPHYSICAL PROCESSES ON TYPHOON NIDA(2016) USING A NEW DOUBLE-MOMENT MICROPHYSICS SCHEME IN THE WEATHER RESEARCH AND FORECASTING MODEL 被引量:5
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作者 LI Zhe ZHANG Yu-tao +2 位作者 LIU Qi-jun FU Shi-zuo MA Zhan-shan 《Journal of Tropical Meteorology》 SCIE 2018年第2期123-130,共8页
The basic structure and cloud features of Typhoon Nida(2016) are simulated using a new microphysics scheme(Liuma) within the Weather Research and Forecasting(WRF) model. Typhoon characteristics simulated with the Lium... The basic structure and cloud features of Typhoon Nida(2016) are simulated using a new microphysics scheme(Liuma) within the Weather Research and Forecasting(WRF) model. Typhoon characteristics simulated with the Liuma microphysics scheme are compared with observations and those simulated with a commonly-used microphysics scheme(WSM6). Results show that using different microphysics schemes does not significantly alter the track of the typhoon but does significantly affect the intensity and the cloud structure of the typhoon. Results also show that the vertical distribution of cloud hydrometeors and the horizontal distribution of peripheral rainband are affected by the microphysics scheme. The mixing ratios of rain water and graupel correlate highly with the vertical velocity component and equivalent potential temperature at the typhoon eye-wall region. According to the simulation with WSM 6 scheme,it is likely that the very low typhoon central pressure results from the positive feedback between hydrometeors and typhoon intensity. As the ice-phase hydrometeors are mostly graupel in the Liuma microphysics scheme, further improvement in this aspect is required. 展开更多
关键词 Liuma microphysics scheme typhoon intensity cloud microphysics typhoon structure Weather research and Forecasting model
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Research on the Model of Consumer Health Information Seeking Behavior via Social Media 被引量:3
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作者 Juan Chen Xiaorong Hou Wenlong Zhao 《International Journal of Communications, Network and System Sciences》 2016年第8期326-337,共13页
Purpose: We aim to create a model of consumer health information seeking behavior via social media, then to have a better understand of it. After that further efforts should be made to provide targeted recommendations... Purpose: We aim to create a model of consumer health information seeking behavior via social media, then to have a better understand of it. After that further efforts should be made to provide targeted recommendations for media managers to promote health communication via social media. Methods: Our custom model was derived from literature review, empirical research was tested by the use of questionnaire investigation, and then the collected data were analyzed by structural equation model tool SmartPLS. Finally, the custom model was modified according to the experimental results of SmartPLS. Results: A total of 239 (66.39%) of the respondents were female and 121 (33.61%) were male. The maximum of two stages of age were 18 - 29 (70.56%), 30 - 39 (13.89%). Wechat (60.28%), QQ Zone (55.22%), Micro-blog (48.89%) were the most commonly used social media to obtain health information. About 44.72% of respondents used social media to obtain health information multiple times a day. The whole numerical values of AVE, cronbach’s alpha, CR and square roots of AVE were above the benchmarks of themselves and showed great reliability and validity. All the 11 hypotheses had obvious statistical significance, the P-value of eight path coefficients exhibited <0.001, one path coefficient exhibited <0.01 and two path coefficients exhibited <0.05. Conclusions: A suitable model of consumer health information seeking behavior via social media was created and some inner relationships were found. Namely, gratification of health information and its platform had a positive effect on attitudes toward health information seeking behavior. Health information literacy and health status were proved to have a significant influence on attitudes toward health information seeking behavior, subject norms and perceived behavioral control respectively. In addition, attitudes toward the health information seeking behavior, subject norms and perceived behavioral control were proved to positively associate with health information seeking behavior intention. 展开更多
关键词 Health Information Seeking Behavior research Model Structural Equation Model Social Media
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A Methodological Study on Using Weather Research and Forecasting(WRF) Model Outputs to Drive a One-Dimensional Cloud Model 被引量:1
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作者 JIN Ling Fanyou KONG +1 位作者 LEI Hengchi HU Zhaoxia 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第1期230-240,共11页
A new method for driving a One-Dimensional Stratiform Cold (1DSC) cloud model with Weather Research and Fore casting (WRF) model outputs was developed by conducting numerical experiments for a typical large-scale ... A new method for driving a One-Dimensional Stratiform Cold (1DSC) cloud model with Weather Research and Fore casting (WRF) model outputs was developed by conducting numerical experiments for a typical large-scale stratiform rainfall event that took place on 4-5 July 2004 in Changchun, China. Sensitivity test results suggested that, with hydrometeor pro files extracted from the WRF outputs as the initial input, and with continuous updating of soundings and vertical velocities (including downdraft) derived from the WRF model, the new WRF-driven 1DSC modeling system (WRF-1DSC) was able to successfully reproduce both the generation and dissipation processes of the precipitation event. The simulated rainfall intensity showed a time-lag behind that observed, which could have been caused by simulation errors of soundings, vertical velocities and hydrometeor profiles in the WRF output. Taking into consideration the simulated and observed movement path of the precipitation system, a nearby grid point was found to possess more accurate environmental fields in terms of their similarity to those observed in Changchun Station. Using profiles from this nearby grid point, WRF-1DSC was able to repro duce a realistic precipitation pattern. This study demonstrates that 1D cloud-seeding models do indeed have the potential to predict realistic precipitation patterns when properly driven by accurate atmospheric profiles derived from a regional short range forecasting system, This opens a novel and important approach to developing an ensemble-based rain enhancement prediction and operation system under a probabilistic framework concept. 展开更多
关键词 cloud-seeding model Weather research and Forecasting (WRF) model rain enhancement
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Review on Quantitative Research Methods of Regional Sustainable Development in China
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作者 Zhang Jinping Qin Yaochen Zhang Erxun 《Chinese Journal of Population,Resources and Environment》 2010年第3期44-53,共10页
Since the 1990s, with the in-depth study and understanding of sustainable development, quantitative study of regional sustainable development (RSD) was increasingly hot in China. Based on quantitative study of RSD fro... Since the 1990s, with the in-depth study and understanding of sustainable development, quantitative study of regional sustainable development (RSD) was increasingly hot in China. Based on quantitative study of RSD from Core Periodical in China National Knowledge Infrastructure (1992–2008), statistical analysis on the annual distribution, periodicals distribution and changes of the distribution were made. And from perspectives of social–economic, ecological, systematic and emerging methods, the course, problems and trends of the quantitative study methods on RSD were examined and analyzed to get a clear summary. By the review, the context on the quantitative study of RSD was to be clarified. The study also showed that, primarily, fields involving quantitative study are expanding; second, big progresses and constant development have been made on the systematic method gradually sophisticated, the flourishing ecological method and emerging new methods in the context of cross and integration which has made complex integrated systems a more satisfactory solution; third, the method system has been more multi-angled, and the clues of independent innovation have been observed despite the fact that the introduction of imported method is the main trend. Although many problems exist, multi-scale study, dynamic timeseries study and inter-regional comparative study will be further exploited and increasingly carried out with the progress of spatial information technology, which would boost the development and application of new methods in RSD study. 展开更多
关键词 regional sustainable development quantitative research models systematic methods ecological methods
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Malaysian Teacher Trainees' Competencies of Accessing, Evaluating, and Applying Information Ethically in Research Process
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作者 Siri Sena bin Baba Harold Fuziah Mohd Nadzar 《Journalism and Mass Communication》 2014年第2期133-145,共13页
The case study attempts to discover with certainty the competency of accessing, evaluating and applying information in research process acquired by undergraduate trainees of Malaysian Teacher Education Institute in th... The case study attempts to discover with certainty the competency of accessing, evaluating and applying information in research process acquired by undergraduate trainees of Malaysian Teacher Education Institute in the northern region of Peninsula Malaysia. Considered as highly important skills that trainee teachers have to acquire a comprehensive understanding of information literacy to pursue a research. Yet, it is a pivotal fact indicated by recent researchers that most future teachers often enter teaching without the necessary information literacy skills and knowledge in research process. The scope of study is based on full-time final year undergraduate trainee teachers for the Educational Degree Programme doing their school based action research in the states of Kedah, Perlis, and Penang. The study analyzes problems and issues faced by these trainee teachers tied up to information literacy competency in doing research process. The study investigates trainees' competencies of accessing, evaluating, and applying information ethically in their research process. The findings hope to give insights to stake holders on the ways to move forward in terms of needs, process and outcomes in accordance with the Malaysian National Information Literacy Agenda. 展开更多
关键词 information literacy competency information seeking behaviour research process model teachereducation final year trainee teachers
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Application of Animal Modeling to Biodefense Research
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作者 Mark A. Suckow ACLAM 《中国实验动物学报》 CAS CSCD 2005年第S1期2-3,共2页
关键词 Application of Animal Modeling to Biodefense research
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Research on Shanghai Technical Standards Development Strategy and Advancing Model
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作者 Shanghai Institution of Standardization 《China Standardization》 2004年第1期40-45,共6页
关键词 research on Shanghai Technical Standards Development Strategy and Advancing Model HIGH WTO
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Research on the hydrogeochemical model for water resources and ecological environment
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《Global Geology》 1998年第1期84-84,共1页
关键词 research on the hydrogeochemical model for water resources and ecological environment
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Solar Energy Resource Characteristics of Photovoltaic Power Station in Shandong Province 被引量:2
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作者 薛德强 王新 王新堂 《Agricultural Science & Technology》 CAS 2013年第4期666-671,共6页
[Objective] The aim was to analyze characters of solar energy in photo- voltaic power stations in Shandong Province. [Method] The models of total solar radiation and scattered radiation were determined, and solar ener... [Objective] The aim was to analyze characters of solar energy in photo- voltaic power stations in Shandong Province. [Method] The models of total solar radiation and scattered radiation were determined, and solar energy resources in pho-tovoltaic power stations were evaluated based on illumination in horizontal plane and cloud data in 123 counties or cities and observed information in Jinan, Fushan and Juxian in 1988-2008. [Result] Solar energy in northern regions in Shandong proved most abundant, which is suitable for photovoltaic power generation; the optimal angle of tilt of photovoltaic array was at 35°, decreasing by 2°-3° compared with local latitude. Total solar radiation received by the slope with optimal angle of tilt exceeded 1 600 kw.h/(m2.a), increasing by 16% compared with horizontal planes. The maximal irradiance concluded by WRF in different regions tended to be volatile in 1 020-1 060 W/m2. [Conclusion] The research provides references for construction of photovoltaic power stations in Shandong Province. 展开更多
关键词 Shandong Province Solar energy resource Photovoltaic power stations Optimum tilt angle WRF(weather research and forecasting model) Maximal daily irradiance
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Numerical Simulation of the Heavy Rainfall in the Yangtze-Huai River Basin during Summer 2003 Using the WRF Model 被引量:13
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作者 LIU Hong-Bo 《Atmospheric and Oceanic Science Letters》 2012年第1期20-25,共6页
In this study, a 47-day regional climate simulation of the heavy rainfall in the Yangtze-Huai River Basin during the summer of 2003 was conducted using the Weather Research and Forecast (WRY) model. The simulation r... In this study, a 47-day regional climate simulation of the heavy rainfall in the Yangtze-Huai River Basin during the summer of 2003 was conducted using the Weather Research and Forecast (WRY) model. The simulation reproduces reasonably well the evolution of the rainfall during the study period's three successive rainy phases, especially the frequent heavy rainfall events occurring in the Huai River Basin. The model captures the major rainfall peak observed by the monitoring stations in the morning. Another peak appears later than that shown by the observations. In addition, the simulation realistically captures not only the evolution of the low-level winds but also the characteristics of their diurnal variation. The strong southwesterly (low-level jet, LLJ) wind speed increases beginning in the early evening and reaches a peak in the morning; it then gradually decreases until the afternoon. The intense LLJ forms a strong convergent circulation pattern in the early morning along the Yangtze-Huai River Basin. This pattern partly explains the rainfall peak observed at this time. This study furnishes a basis for the further analysis of the mechanisms of evolution of the LLJ and for the further study of the interactions between the LLJ and rainfall. 展开更多
关键词 heavy rainfall Yangtze-Huai River Basin the Weather research and Forecast model low-level jet
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Simulations of Microphysics and Precipitation in a Stratiform Cloud Case over Northern China:Comparison of Two Microphysics Schemes 被引量:4
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作者 Tuanjie HOU Hengchi LEI +2 位作者 Zhaoxia HU Jiefan YANG Xingyu LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第1期117-129,共13页
Using the Weather Research and Forecasting(WRF)model with two different microphysics schemes,the Predicted Particle Properties(P3)and the Morrison double-moment parameterizations,we simulated a stratiform rainfall eve... Using the Weather Research and Forecasting(WRF)model with two different microphysics schemes,the Predicted Particle Properties(P3)and the Morrison double-moment parameterizations,we simulated a stratiform rainfall event on 20–21 April 2010.The simulation output was compared with precipitation and aircraft observations.The aircraft-observed moderate-rimed dendrites and plates indicated that riming contributed significantly to ice particle growth at the mature precipitation stage.Observations of dendrite aggregation and capped columns suggested that aggregation coexisted with deposition or riming and played an important role in producing many large particles.The domain-averaged values of the 24-h surface precipitation accumulation from the two schemes were quite close to each other.However,differences existed in the temporal and spatial evolutions of the precipitation distribution.An analysis of the surface precipitation temporal evolution indicated faster precipitation in Morrison,while P3 indicated slower rainfall by shifting the precipitation pattern eastward toward what was observed.The differences in precipitation values between the two schemes were related to the cloud water content distribution and fall speeds of rimed particles.P3 simulated the stratiform precipitation event better as it captured the gradual transition in the mass-weighted fall speeds and densities from unrimed to rimed particles. 展开更多
关键词 stratiform cloud RIMING Weather research and Forecasting model fall speed
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Simulation of a torrential rainstorm in Xinjiang and gravity wave analysis 被引量:4
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作者 Rui Yang Yi Liu +1 位作者 Ling-Kun Ran Yu-Li Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期573-580,共8页
We used a weather research and forecasting model to simulate a torrential rainstorm that occurred in Xinjiang,China during June 16–17,2016.The model successfully simulated the rainfall area,precipitation intensity,an... We used a weather research and forecasting model to simulate a torrential rainstorm that occurred in Xinjiang,China during June 16–17,2016.The model successfully simulated the rainfall area,precipitation intensity,and changes in precipitation.We identified a clear wave signal using the two-dimensional fast Fourier transform method;the waves propagated westwards,with wavelengths of 45–20 km,periods of 50–120 min,and phase velocities mainly concentrated in the-25 m/s to-10 m/s range.The results of wavelet cross-spectral analysis further confirmed that the waves were gravity waves,peaking at 11:00 UTC,June 17,2016.The gravity wave signal was identified along 79.17–79.93°E,81.35–81.45°E and 81.5–81.83°E.The gravity waves detected along 81.5–81.83°E corresponded well with precipitation that accumulated in 1 h,indicating that gravity waves could be considered a rainstorm precursor in future precipitation forecasts. 展开更多
关键词 gravity wave RAINSTORM spectral analysis methods weather research and forecasting model
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Simulation of Quasi-Linear Mesoscale Convective Systems in Northern China:Lightning Activities and Storm Structure 被引量:7
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作者 Wanli LI Xiushu QIE +2 位作者 Shenming FU Debin SU Yonghai SHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第1期85-100,共16页
Two intense quasi-linear mesoscale convective systems(QLMCSs) in northern China were simulated using the WRF(Weather Research and Forecasting) model and the 3D-Var(three-dimensional variational) analysis system ... Two intense quasi-linear mesoscale convective systems(QLMCSs) in northern China were simulated using the WRF(Weather Research and Forecasting) model and the 3D-Var(three-dimensional variational) analysis system of the ARPS(Advanced Regional Prediction System) model.A new method in which the lightning density is calculated using both the precipitation and non-precipitation ice mass was developed to reveal the relationship between the lightning activities and QLMCS structures.Results indicate that,compared with calculating the results using two previous methods,the lightning density calculated using the new method presented in this study is in better accordance with observations.Based on the calculated lightning densities using the new method,it was found that most lightning activity was initiated on the right side and at the front of the QLMCSs,where the surface wind field converged intensely.The CAPE was much stronger ahead of the southeastward progressing QLMCS than to the back it,and their lightning events mainly occurred in regions with a large gradient of CAPE.Comparisons between lightning and non-lightning regions indicated that lightning regions featured more intense ascending motion than non-lightning regions;the vertical ranges of maximum reflectivity between lightning and non-lightning regions were very different;and the ice mixing ratio featured no significant differences between the lightning and non-lightning regions. 展开更多
关键词 quasi-linear mesoscale convective system Weather research and Forecasting model Advanced Regional Prediction System model precipitation and non-precipitation ice
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Validation of WRF model on simulating forcing data for Heihe River Basin 被引量:10
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作者 XiaoDuo Pan Xin Li 《Research in Cold and Arid Regions》 2011年第4期344-357,共14页
The research of coupling WRF (Weather Research and Forecasting Model) with a land surface model is enhanced to explore the interaction of the atmosphere and land surface; however, regional applicability of WRF model... The research of coupling WRF (Weather Research and Forecasting Model) with a land surface model is enhanced to explore the interaction of the atmosphere and land surface; however, regional applicability of WRF model is questioned. In order to do the validation of WRF model on simulating forcing data for the Heihe River Basin, daily meteorological observation data from 15 stations of CMA (China Meteorological Administration) and hourly meteorological observation data from seven sites of WATER (Watershed Airborne Telemetry Experimental Research) are used to compare with WRF simulations, with a time range of a whole year for 2008. Results show that the average MBE (Mean Bias Error) of daily 2-m surface temperature, surface pressure, 2-m relative humidity and 10-m wind speed were -0.19 ℃, -4.49 hPa, 4.08% and 0.92 m/s, the average RMSE (Root Mean Square Error) of them were 2.11 ℃, 5.37 hPa, 9.55% and 1.73 m/s, and the average R (correlation coefficient) of them were 0.99, 0.98, 0.80 and 0.55, respectively. The average MBE of hourly 2-m surface temperature, surface pressure, 2-m relative humidity, 10-m wind speed, downward shortwave radiation and downward longwave were-0.16 ℃,-6.62 hPa,-5.14%, 0.26 m/s, 33.0 W/m^2 and-6.44 W/m^2, the average RMSE of them were 2.62 ℃, 17.10 hPa, 20.71%, 2.46 m/s, 152.9 W/m^2 and 53.5 W/m^2, and the average R of them were 0.96, 0.97, 0.70, 0.26, 0.91 and 0.60, respectively. Thus, the following conclusions were obtained: (1) regardless of daily or hourly validation, WRF model simulations of 2-m surface temperature, surface pressure and relative humidity are more reliable, especially for 2-m surface air temperature and surface pressure, the values of MBE were small and R were more than 0.96; (2) the WRF simulating downward shortwave radiation was relatively good, the average R between WRF simulation and hourly observation data was above 0.9, and the average R of downward longwave radiation was 0.6; (3) both wind speed and rainfall simulated from WRF model did not agree well with observation data. 展开更多
关键词 forcing data weather research and forecasting model watershed airborne telemetry experimental research Heihe River Basin
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