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Rock mass quality prediction on tunnel faces with incomplete multi-source dataset via tree-augmented naive Bayesian network 被引量:1
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作者 Hongwei Huang Chen Wu +3 位作者 Mingliang Zhou Jiayao Chen Tianze Han Le Zhang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期323-337,共15页
Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel faces.In tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantita... Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel faces.In tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantitative parameters.However,due to the harsh on-site construction conditions,it is rather difficult to obtain some of the evaluation parameters which are essential for the rock mass quality prediction.In this study,a novel improved Swin Transformer is proposed to detect,segment,and quantify rock mass characteristic parameters such as water leakage,fractures,weak interlayers.The site experiment results demonstrate that the improved Swin Transformer achieves optimal segmentation results and achieving accuracies of 92%,81%,and 86%for water leakage,fractures,and weak interlayers,respectively.A multisource rock tunnel face characteristic(RTFC)dataset includes 11 parameters for predicting rock mass quality is established.Considering the limitations in predictive performance of incomplete evaluation parameters exist in this dataset,a novel tree-augmented naive Bayesian network(BN)is proposed to address the challenge of the incomplete dataset and achieved a prediction accuracy of 88%.In comparison with other commonly used Machine Learning models the proposed BN-based approach proved an improved performance on predicting the rock mass quality with the incomplete dataset.By utilizing the established BN,a further sensitivity analysis is conducted to quantitatively evaluate the importance of the various parameters,results indicate that the rock strength and fractures parameter exert the most significant influence on rock mass quality. 展开更多
关键词 Rock mass quality Tunnel faces Incomplete multi-source dataset Improved Swin Transformer Bayesian networks
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A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM
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作者 Yili Wang Changsheng Li Xiaofeng Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期463-474,共12页
When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ... When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of layers.To address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent network.By leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration process.The analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,respectively.The model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target plates.The maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed model.Moreover,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves. 展开更多
关键词 Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting multi-source fusion
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The 18th Workshop on Antarctic Meteorology and Climate
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作者 Anastasia J.TOMANEK Ethan J.KOUDELKA +4 位作者 Mariana F.LITELL Taylor P.NORTON Mckenzie J.DICE Isabella I.ONSI Matthew A.LAZZARA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第12期2495-2504,共10页
The 18th Workshop on Antarctic Meteorology and Climate was held on 31 May through 2 June 2023.The Antarctic Meteorological Research and Data Center hosted this hybrid workshop at the Pyle Center at the University of W... The 18th Workshop on Antarctic Meteorology and Climate was held on 31 May through 2 June 2023.The Antarctic Meteorological Research and Data Center hosted this hybrid workshop at the Pyle Center at the University of Wisconsin-Madison in Madison,WI,USA.Global members of the Antarctic meteorological community gathered to present and discuss topics from scientific research to operational support within Antarctic meteorology and climate.Students and early career professionals chaired various presentations and discussions while all attendees engaged to share results,build collaborative plans,and discuss further developments.The main workshop topics included updates on the current Automatic Weather Station(AWS)networks,challenges,and planning concerning Antarctic forecasting and operational services,Antarctic numerical modeling systems,observational applications and research,and Antarctic community and data sources.Across six sessions,over 25 different presenters elaborated on their work in areas such as field season updates,atmospheric rivers,remote sensing,the Antarctic Mesoscale Prediction System(AMPS),and forecasting challenges due to data scarcity.Workshop discussions resulted in several key outcomes and action items regarding fieldwork impacts,exploration of field techniques,observation coverage,and communication between operations and research scientists.Future workshops will provide opportunities for continued discussion on the evolution of the AWS network and operational needs while providing a venue to promote collaboration and cooperation for Antarctic meteorology and climate activities. 展开更多
关键词 ANTARCTICA polar meteorology automatic weather station polar modeling polar climatology
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Multi-source heterogeneous data access management framework and key technologies for electric power Internet of Things
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作者 Pengtian Guo Kai Xiao +1 位作者 Xiaohui Wang Daoxing Li 《Global Energy Interconnection》 EI CSCD 2024年第1期94-105,共12页
The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initiall... The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initially built a power IoT architecture comprising a perception,network,and platform application layer.However,owing to the structural complexity of the power system,the construction of the power IoT continues to face problems such as complex access management of massive heterogeneous equipment,diverse IoT protocol access methods,high concurrency of network communications,and weak data security protection.To address these issues,this study optimizes the existing architecture of the power IoT and designs an integrated management framework for the access of multi-source heterogeneous data in the power IoT,comprising cloud,pipe,edge,and terminal parts.It further reviews and analyzes the key technologies involved in the power IoT,such as the unified management of the physical model,high concurrent access,multi-protocol access,multi-source heterogeneous data storage management,and data security control,to provide a more flexible,efficient,secure,and easy-to-use solution for multi-source heterogeneous data access in the power IoT. 展开更多
关键词 Power Internet of Things Object model High concurrency access Zero trust mechanism multi-source heterogeneous data
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Runout prediction of potential landslides based on the multi-source data collaboration analysis on historical cases
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作者 Jun Sun Yu Zhuang Ai-guo Xing 《China Geology》 CAS CSCD 2024年第2期264-276,共13页
Long runout landslides involve a massive amount of energy and can be extremely hazardous owing to their long movement distance,high mobility and strong destructive power.Numerical methods have been widely used to pred... Long runout landslides involve a massive amount of energy and can be extremely hazardous owing to their long movement distance,high mobility and strong destructive power.Numerical methods have been widely used to predict the landslide runout but a fundamental problem remained is how to determine the reliable numerical parameters.This study proposes a framework to predict the runout of potential landslides through multi-source data collaboration and numerical analysis of historical landslide events.Specifically,for the historical landslide cases,the landslide-induced seismic signal,geophysical surveys,and possible in-situ drone/phone videos(multi-source data collaboration)can validate the numerical results in terms of landslide dynamics and deposit features and help calibrate the numerical(rheological)parameters.Subsequently,the calibrated numerical parameters can be used to numerically predict the runout of potential landslides in the region with a similar geological setting to the recorded events.Application of the runout prediction approach to the 2020 Jiashanying landslide in Guizhou,China gives reasonable results in comparison to the field observations.The numerical parameters are determined from the multi-source data collaboration analysis of a historical case in the region(2019 Shuicheng landslide).The proposed framework for landslide runout prediction can be of great utility for landslide risk assessment and disaster reduction in mountainous regions worldwide. 展开更多
关键词 Landslide runout prediction Drone survey multi-source data collaboration DAN3D numerical modeling Jianshanying landslide Guizhou Province Geological hazards survey engineering
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A Web-Based Approach for the Efficient Management of Massive Multi-source 3D Models
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作者 ZHAO Qiansheng TANG Ruibing +1 位作者 PENG Mingjun GUO Mingwu 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第3期24-41,共18页
Effectively managing extensive,multi-source,and multi-level real-scene 3D models for responsive retrieval scheduling and rapid visualization in the Web environment is a significant challenge in the current development... Effectively managing extensive,multi-source,and multi-level real-scene 3D models for responsive retrieval scheduling and rapid visualization in the Web environment is a significant challenge in the current development of real-scene 3D applications in China.In this paper,we address this challenge by reorganizing spatial and temporal information into a 3D geospatial grid.It introduces the Global 3D Geocoding System(G_(3)DGS),leveraging neighborhood similarity and uniqueness for efficient storage,retrieval,updating,and scheduling of these models.A combination of G_(3)DGS and non-relational databases is implemented,enhancing data storage scalability and flexibility.Additionally,a model detail management scheduling strategy(TLOD)based on G_(3)DGS and an importance factor T is designed.Compared with mainstream commercial and open-source platforms,this method significantly enhances the loadable capacity of massive multi-source real-scene 3D models in the Web environment by 33%,improves browsing efficiency by 48%,and accelerates invocation speed by 40%. 展开更多
关键词 massive multi-source real-scene 3D model non-relational database global 3D geocoding system importance factor massive model management
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Relationship between Calligraphy and Meteorology
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作者 Licheng LIU Xunzhi GAO Liang GAO 《Meteorological and Environmental Research》 2024年第4期8-10,14,共4页
Since ancient times,calligraphy and meteorology have had an inseparable relationship.Wang Xizhi s Prologue to the Collection of Poems Composed at the Orchid Pavilion records the beautiful scenery of mild wind and brig... Since ancient times,calligraphy and meteorology have had an inseparable relationship.Wang Xizhi s Prologue to the Collection of Poems Composed at the Orchid Pavilion records the beautiful scenery of mild wind and bright sun,as well as the relaxed and joyful mood of people in such weather.Su Shi s Cold Food Calligraphy Copybook records the scenery of solar terms and the author s psychological changes during these solar terms through calligraphy.The Quick Snow and Clear Time Calligraphy Copybook also reflects the grandeur of snowy days and the customs of literati recording weather and sharing it with friends.In Sun Guoting s Shupu,it is clearly stated that the third element of the"five harmony and five obedience"refers to the clear sky,humid air,and pleasant climate,and excellent climatic conditions are conducive to writing. 展开更多
关键词 CALLIGRAPHY meteorology
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Enhanced permeability prediction in porous media using particle swarm optimization with multi-source integration
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作者 Zhiping Chen Jia Zhang +2 位作者 Daren Zhang Xiaolin Chang Wei Zhou 《Artificial Intelligence in Geosciences》 2024年第1期282-293,共12页
Accurately and efficiently predicting the permeability of porous media is essential for addressing a wide range of hydrogeological issues.However,the complexity of porous media often limits the effectiveness of indivi... Accurately and efficiently predicting the permeability of porous media is essential for addressing a wide range of hydrogeological issues.However,the complexity of porous media often limits the effectiveness of individual prediction methods.This study introduces a novel Particle Swarm Optimization-based Permeability Integrated Prediction model(PSO-PIP),which incorporates a particle swarm optimization algorithm enhanced with dy-namic clustering and adaptive parameter tuning(KGPSO).The model integrates multi-source data from the Lattice Boltzmann Method(LBM),Pore Network Modeling(PNM),and Finite Difference Method(FDM).By assigning optimal weight coefficients to the outputs of these methods,the model minimizes deviations from actual values and enhances permeability prediction performance.Initially,the computational performances of the LBM,PNM,and FDM are comparatively analyzed on datasets consisting of sphere packings and real rock samples.It is observed that these methods exhibit computational biases in certain permeability ranges.The PSOPIP model is proposed to combine the strengths of each computational approach and mitigate their limitations.The PSO-PIP model consistently produces predictions that are highly congruent with actual permeability values across all prediction intervals,significantly enhancing prediction accuracy.The outcomes of this study provide a new tool and perspective for the comprehensive,rapid,and accurate prediction of permeability in porous media. 展开更多
关键词 Porous media Particle swarm optimization algorithm multi-source data integration Permeability prediction
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Response of warm season secondary pollutants to emissions and meteorology in the North China Plain region during 2018-2022
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作者 Yueqi Gao Siyu Wang +7 位作者 Zhaolei Zhang Wenxuan Yu Shuai Wang Shengqiang Zhu Peng Wang Yan Li Yele Sun Hongliang Zhang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第4期58-64,共7页
自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_... 自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_(2)的年下降速率分别为1%和0.5%SIA和SOA也显著减少,每年分别减少9%和6%PM_(2.5)主要因排放减少而下降,而O_(3)则受气象影响而波动.硫酸盐和铵下降的主因是减排,而硝酸盐对气象变化敏感排放和气象变化对SOA的总体减少同样重要,但人为SOA对排放控制敏感生物SOA易受气象变化影响.研究强调了控制人为排放对缓解NCP地区夏季二次污染的重要性. 展开更多
关键词 PM_(2.5) 二次污染物 人为排放 气象 华北平原
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Development and Application of the Edition System of Agricultural Meteorology Short Message in Liaoning Province
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作者 李岚 明惠青 +4 位作者 唐亚平 孙婧 王艳丽 孙丽 赵淼 《Meteorological and Environmental Research》 CAS 2010年第5期92-96,共5页
In order to meet the needs of Agricultural Meteorology business and research,an edition system of agricultural meteorology short message was established based on the Microsoft Access 2000 database and visualization de... In order to meet the needs of Agricultural Meteorology business and research,an edition system of agricultural meteorology short message was established based on the Microsoft Access 2000 database and visualization developing software Visual Basic 6.0 in Liaoning Province.The basic principles of agro-meteorological text editing and system optimization ideas were pointed out.The meteorological conditions of the main crops growth needed in material library were introduced. 展开更多
关键词 Agricultural meteorology Short message System development APPLICATION China
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Separation method for multi-source blended seismic data
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作者 王汉闯 陈生昌 +1 位作者 张博 佘德平 《Applied Geophysics》 SCIE CSCD 2013年第3期251-264,357,共15页
Multi-source seismic technology is an efficient seismic acquisition method that requires a group of blended seismic data to be separated into single-source seismic data for subsequent processing. The separation of ble... Multi-source seismic technology is an efficient seismic acquisition method that requires a group of blended seismic data to be separated into single-source seismic data for subsequent processing. The separation of blended seismic data is a linear inverse problem. According to the relationship between the shooting number and the simultaneous source number of the acquisition system, this separation of blended seismic data is divided into an easily determined or overdetermined linear inverse problem and an underdetermined linear inverse problem that is difficult to solve. For the latter, this paper presents an optimization method that imposes the sparsity constraint on wavefields to construct the object function of inversion, and the problem is solved by using the iterative thresholding method. For the most extremely underdetermined separation problem with single-shooting and multiple sources, this paper presents a method of pseudo-deblending with random noise filtering. In this method, approximate common shot gathers are received through the pseudo-deblending process, and the random noises that appear when the approximate common shot gathers are sorted into common receiver gathers are eliminated through filtering methods. The separation methods proposed in this paper are applied to three types of numerical simulation data, including pure data without noise, data with random noise, and data with linear regular noise to obtain satisfactory results. The noise suppression effects of these methods are sufficient, particularly with single-shooting blended seismic data, which verifies the effectiveness of the proposed methods. 展开更多
关键词 multi-source data separation linear inverse problem sparsest constraint pseudo-deblending filtering
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An Overview of Tropical Cyclone and Tropical Meteorology Research Progress 被引量:18
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作者 陈联寿 罗会邦 +1 位作者 端义宏 余辉 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第3期505-514,共10页
There has been much progress in the study of tropical cyclones and tropical meteorology in China in the past few years. A new atmospheric field experiment of tropical cyclone landfall with the acronym of CLATEX (China... There has been much progress in the study of tropical cyclones and tropical meteorology in China in the past few years. A new atmospheric field experiment of tropical cyclone landfall with the acronym of CLATEX (China Landfalling Typhoon Experiment) was implemented in July-August 2002. The boundary layer characteristics of the target typhoon Vongfong and the mesoscale structural features of other land-falling typhoons were studied. In addition, typhoon track operational forecasting errors in the last decade have been reduced because the operational monitoring equipment and forecast techniques were improved. Some results from the research program on tropical cvclone landfall, structure and intensity change, inten-sification near coastal waters, interaction between tropical cyclone and mid-latitude circulation, and the interaction among different scales of motion are described in this paper. Four major meteorological scien-tific experiments in China with international cooperation were implemented in 1998: the South China Sea monsoon field experiment (SCSMEX), the Tibetan Plateau field experiment (TIPEX), the Huaihe River basin energy and water cycle experiment (HUBEX), and the South China heavy rain scientific experiment (HUAMEX). Although these field experiments have different scientific objectives, they commonly relate to monsoon activities and they interact with each other. The valuable intensive observation data that were obtained have already been shared internationally. Some new findings have been published recently. Other research work in China, such as the tropical air-sea interaction, tropical atmospheric circulation, and weather systems, are reviewed in this paper as well. Some research results have shown that the rainfall anomalies for different regions in China were closely related to the stages of El Nino events. 展开更多
关键词 tropical cyclones tropical meteorology research progress
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Current Status and Future Challenges of Weather Radar Polarimetry: Bridging the Gap between Radar Meteorology/Hydrology/Engineering and Numerical Weather Prediction 被引量:10
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作者 Guifu ZHANG Vivek N.MAHALE +25 位作者 Bryan J.PUTNAM Youcun QI Qing CAO ANDrew D.BYRD Petar BUKOVCIC Dusan S.ZRNIC Jidong GAO Ming XUE Youngsun JUNG Heather D.REEVES Pamela L.HEINSELMAN AlexANDer RYZHKOV Robert D.PALMER Pengfei ZHANG Mark WEBER Greg M.MCFARQUHAR Berrien MOORE III Yan ZHANG Jian ZHANG J.VIVEKANANDAN Yasser AL-RASHID Richard L.ICE Daniel S.BERKOWITZ Chong-chi TONG Caleb FULTON Richard J.DOVIAK 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第6期571-588,共18页
After decades of research and development, the WSR-88 D(NEXRAD) network in the United States was upgraded with dual-polarization capability, providing polarimetric radar data(PRD) that have the potential to improve we... After decades of research and development, the WSR-88 D(NEXRAD) network in the United States was upgraded with dual-polarization capability, providing polarimetric radar data(PRD) that have the potential to improve weather observations,quantification, forecasting, and warnings. The weather radar networks in China and other countries are also being upgraded with dual-polarization capability. Now, with radar polarimetry technology having matured, and PRD available both nationally and globally, it is important to understand the current status and future challenges and opportunities. The potential impact of PRD has been limited by their oftentimes subjective and empirical use. More importantly, the community has not begun to regularly derive from PRD the state parameters, such as water mixing ratios and number concentrations, used in numerical weather prediction(NWP) models.In this review, we summarize the current status of weather radar polarimetry, discuss the issues and limitations of PRD usage, and explore potential approaches to more efficiently use PRD for quantitative precipitation estimation and forecasting based on statistical retrieval with physical constraints where prior information is used and observation error is included. This approach aligns the observation-based retrievals favored by the radar meteorology community with the model-based analysis of the NWP community. We also examine the challenges and opportunities of polarimetric phased array radar research and development for future weather observation. 展开更多
关键词 WEATHER RADAR POLARIMETRY RADAR meteorology numerical WEATHER prediction data ASSIMILATION MICROPHYSICS parameterization forward operator
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Characteristics of Micrometeorology in the Surface Layer in the Tibetan Plateau 被引量:5
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作者 刘辉志 张宏升 +5 位作者 卞林根 陈家宜 周明煜 徐祥德 李诗明 赵翼浚 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第1期73-88,共16页
The data of the meteorological elements in the surface layer have been analyzed which were obtained during the IOP of TIPEX from May to July 1998 inG&#283;rz&#283;, Damxung and Qamdo. The characteristics of th... The data of the meteorological elements in the surface layer have been analyzed which were obtained during the IOP of TIPEX from May to July 1998 inG&#283;rz&#283;, Damxung and Qamdo. The characteristics of the diurnal variations and the vertical profiles of the wind velocity, temperature and humidity in the surface layer have been investigated. Some interesting results have been obtained. The moisture inversion phenomena occured during the daytime in the surface layer have also been discussed. 展开更多
关键词 Diurnal variation of meteorological element Vertical profile Tibetan Plateau
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Progress in Marine Meteorology Studies in China during 1999-2002 被引量:3
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作者 王东晓 秦曾灏 施平 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第3期485-496,共12页
The progresses of marine meteorology studies achieved in China during the four year period from 1999 to 2002 are summarized in six directions: air-sea flux, marine meteorology in high latitudes, marine disasters, conn... The progresses of marine meteorology studies achieved in China during the four year period from 1999 to 2002 are summarized in six directions: air-sea flux, marine meteorology in high latitudes, marine disasters, connection between ocean and weather/climate in China, remote sensing applications and new methodologies in marine meteorology. Compared to the previous ones, these studies adopted much more first-hand datasets, and more scientific issues were involved. As an exciting remark, there were so many contributions done by the young scientists. A brief statement about the research strategy of marine meteorology in China for the coming years is also given. 展开更多
关键词 marine meteorology China field observation marine disaster remote sensing application
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Marine Meteorology Research Progress of China from 2003 to 2006 被引量:2
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作者 王东晓 张燕 +1 位作者 曾丽丽 罗琳 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第1期17-30,共14页
The progress in marine meteorology research achieved by scientists in China during the four-year period from 2003 to 2006 is summarized under four categories: marine disaster study, typhoon over the ocean, ocean-atmo... The progress in marine meteorology research achieved by scientists in China during the four-year period from 2003 to 2006 is summarized under four categories: marine disaster study, typhoon over the ocean, ocean-atmosphere monitoring technology, and ocean-atmosphere forecasting technology. Compared to the previous four years, many more first-hand datasets have been obtained and more scientific issues have been addressed. In particular, many contributions have been made by young scientists. A brief statement on the research strategy of marine meteorology in China for the coming years is given at the end. 展开更多
关键词 marine meteorology marine disaster remote sensing monitoring and forecasting technology
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Cycle-by-Cycle Queue Length Estimation for Signalized Intersections Using Multi-Source Data 被引量:4
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作者 Zhongyu Wang Qing Cai +2 位作者 Bing Wu Yinhai Wang Linbo Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第2期86-93,共8页
In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is pre... In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is presented for estimating vehicular queue length using data from both point detectors and probe vehicles. The methodology applies the shockwave theory to model queue evolution over time and space. Using probe vehicle locations and times as well as point detector measured traffic states,analytical formulations for calculating the maximum and minimum( residual) queue length are developed. The proposed methodology is verified using ground truth data collected from numerical experiments conducted in Shanghai,China. It is found that the methodology has a mean absolute percentage error of 17. 09%,which is reasonably effective in estimating the queue length at traffic signalized intersections. Limitations of the proposed models and algorithms are also discussed in the paper. 展开更多
关键词 QUEUE LENGTH estimation multi-source data TRAFFIC SIGNALS TRAFFIC SHOCKWAVE theory
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Chinese investigation and research in Southern Ocean physical oceanography and meteorology during the Chinese Polar Programs 2011–2015 被引量:2
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作者 GAO Libao WEI Zexun +1 位作者 GUO Guijun SHI Jiuxin 《Advances in Polar Science》 2016年第4期209-218,共10页
Within the context of developing a research presence in the Antarctic region, the first phase of the Chinese Polar Programs covered the period 2011-2015, which almost coincided with the 12th Five-Year Plan (2011-2015... Within the context of developing a research presence in the Antarctic region, the first phase of the Chinese Polar Programs covered the period 2011-2015, which almost coincided with the 12th Five-Year Plan (2011-2015). For the promotion of full understanding of the progress of Chinese expeditions and research in Antarctica, the observations and achievements of cruises during 2011-2015 are summarized in this paper. Four Antarctic cruises (28th-31st) were performed in the Prydz Bay and Antarctic Peninsula regions during the first phase of the Polar Programs. These cruises performed systemic collections of physical oceanographic and meteorological data to support further research on the ice-ocean-atmosphere interactions in Antarctica. Overall, 248 CTD/LADCP stations, 66 microstructure profiles, 507 XBT/XCTDs, 181 air sounding balloons, 58000 total gaseous mercury (TGM) concentrations, 452 aerosol samples, 294 atmospheric samples, 11 moorings, and 28 surface drifters were acquired or deployed during the four cruises. Using these extensive observations and other data, Chinese scientists have achieved new recognition in the fields of Southern Ocean physical oceanography and meteorology, as well as in other interdisciplinary subjects. These studies, which have been associated with scientific techniques, instrumentation, ocean circulation, water mass formation, energy transformation, and carbon uptake, have elucidated the dynamic mechanisms and potential effects of climate change in Antarctica. Finally, some observations based on experience gained during previous Chinese Antarctic Research and Expedition campaigns are summarized with advice for the improvement of future investigations in the Antarctic region. 展开更多
关键词 physical oceanography meteorology Five-Year Plan CHINARE Chinese Polar Programs
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The Research on Synergic Development Mechanism of Oceanic Meteorology Modernization in the Huang-Bohai Region 被引量:1
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作者 Wang Wei Gong Xiaoqing +1 位作者 Liu Lili Wang Qinliang 《Meteorological and Environmental Research》 CAS 2019年第3期57-60,共4页
To study the cooperative development mechanism of ocean meteorological modernization of Huang-Bohai,we analyze the situation of ocean meteorological modernization in Huang-Bohai with the method of an new five-force mo... To study the cooperative development mechanism of ocean meteorological modernization of Huang-Bohai,we analyze the situation of ocean meteorological modernization in Huang-Bohai with the method of an new five-force model and the analyses of strengths,weaknesses,opportunities and threats (SWOT analysis).As the research results shown,the advantages of ocean meteorological modernization of Huang-Bohai mainly include three aspects which are ocean meteorological observation system,ocean meteorological warning information release and the construction of ocean meteorological center;the disadvantages contain that stereo-observation ability of the ocean meteorology is insufficiency,and the precision forecast technology and the cooperative development are deficiency in ocean meteorology;opportunities also include three aspects which are "The Belt and Road",and development of new technology and new warning system on meteorology disasters;threats mainly contain the main influencing weather system,the potential social competition and hazard factors.The use of different functions and combination innovation of five forces,i.e.,attractiveness,cohesiveness,radiating power,repulsiveness and affinity,could promote the cooperative development of ocean meteorological modernization in the Huang-Bohai. 展开更多
关键词 Pan-Bohai Synergic development meteorology MODERNIZATION EARLY WARNING OCEANIC meteorology
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Numerical investigation of the shockwave overpressure fields of multi-sources FAE explosions 被引量:4
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作者 Chun-hua Bai Xing-yu Zhao +1 位作者 Jian Yao Bin-feng Sun 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第4期1168-1177,共10页
Shockwaves from fuel-air explosive(FAE)cloud explosions may cause significant casualties.The ground overpressure field is usually used to evaluate the damage range of explosion shockwaves.In this paper,a finite elemen... Shockwaves from fuel-air explosive(FAE)cloud explosions may cause significant casualties.The ground overpressure field is usually used to evaluate the damage range of explosion shockwaves.In this paper,a finite element model of multi-sources FAE explosion is established to simulate the process of multiple shockwaves propagation and interaction.The model is verified with the experimental data of a fourfoldsource FAE explosion,with the total fuel mass of 340 kg.Simulation results show that the overpressure fields of multi-sources FAE explosions are different from that of the single-source.In the case of multisources,the overpressure fields are influenced significantly by source scattering distance and source number.Subsequently,damage ranges of overpressure under three different levels are calculated.Within a suitable source scattering distance,the damage range of multi-sources situation is greater than that of the single-source,under the same amount of total fuel mass.This research provides a basis for personnel shockwave protection from multi-sources FAE explosion. 展开更多
关键词 Fuel-air explosive Numerical simulation multi-sources explosion Shockwave overpressure field
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