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Comparison of the Minimum Bounding Rectangle and Minimum Circumscribed Ellipse of Rain Cells from TRMM

Advances in Atmospheric Sciences 2024年第3期41卷 391-406页

作者： hongke cai Yaqin MAO Xuanhao ZHU Yunfei FU Renjun ZHOU Plateau Atmospheric and Environment Laboratory of Sichuan Province School of Atmospheric SciencesChengdu University of Information TechnologyChengdu 610225China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Center for Atmospheric Optics Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China

Based on the TRMM dataset, this paper compares the applicability of the improved MCE(minimum circumscribed ellipse), MBR(minimum bounding rectangle), and DIA(direct indexing area) methods for rain cell fitting. These three methods can reflect the geometric characteristics of clouds and apply geometric parameters to estimate the real dimensions of rain cells. The MCE method shows a major advantage in identifying the circumference of rain cells. The circumference of rain cells identified by MCE in most samples is smaller than that identified by DIA and MBR, and more similar to the observed rain cells. The area of rain cells identified by MBR is relatively robust. For rain cells composed of many pixels(N> 20), the overall performance is better than that of MCE, but the contribution of MBR to the best identification results,which have the shortest circumference and the smallest area, is less than that of MCE. The DIA method is best suited to small rain cells with a circumference of less than 100 km and an area of less than 120 km^(2), but the overall performance is mediocre. The MCE method tends to achieve the highest success at any angle, whereas there are fewer “best identification”results from DIA or MBR and more of the worst ones in the along-track direction and cross-track direction. Through this comprehensive comparison, we conclude that MCE can obtain the best fitting results with the shortest circumference and the smallest area on behalf of the high filling effect for all sizes of rain cells.

关键词： TRMM minimum bounding rectangle minimum circumscribed ellipse

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Testing method of rock structural plane using digital drilling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2563-2578页

作者： Qi Wang Yuncai Wang Bei Jiang hongke Gao Fenglin Ma Dahu Zhai Songlin cai State Key Laboratory for Tunnel Engineering China University of Mining and Technology(Beijing)Beijing100083China

The rock mass consists of rock blocks and structural planes,which can reduce its integrity and ***,accurately obtaining the characteristics of the rock mass structural plane is a prerequisite for evaluating stability and designing supports in underground ***,there are no effective testing methods for the characteristic parameters of the rock mass structural plane in underground *** paper presents the digital drilling technology as a new testing method of rock mass structural *** rock specimens with cracks of varying widths and angles were used to simulate the rock mass structural planes,and the multifunctional rock mass digital drilling test system was employed to carry out the digital drilling *** analysis focuses on the variation laws of drilling parameters,such as drilling pressure and drilling torque,affected by the characteristics of prefabricated cracks,and clarifies the degradation mechanism of rock equivalent compressive ***,an identification model for the characteristic parameters of rock mass structural planes during drilling is *** test results indicate that the average difference of the characteristics of prefabricated cracks identified by the equivalent compressive strength is 2.45and 0.82 mm,*** identification model while drilling is verified to be correct due to the high identification *** on this,a method for testing the characteristic parameters of the surrounding rock structural plane while drilling is *** research offers a theoretical and methodological foundation for precise in situ identification of structural planes of the surrounding rock in underground engineering.

关键词： Structural planes in the rock mass Digital drilling Drilling parameters Equivalent compressive strength Testing method

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Main Detrainment Height of Deep Convection Systems over the Tibetan Plateau and Its Southern Slope

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Advances in Atmospheric Sciences 2019年第10期36卷 1078-1088页

作者： Quanliang CHEN Guolu GAO Yang LI hongke cai Xin ZHOU Zhenglin WANG School of Atmospheric Sciences Chengdu University of Information Technology and Plateau Atmosphere and Environment Key Laboratory of Sichuan Province

Deep convection systems (DCSs) can rapidly lift water vapor and other pollutants from the lower troposphere to the upper troposphere and lower stratosphere. The main detrainment height determines the level to which the air parcel is lifted. We analyzed the main detrainment height over the Tibetan Plateau and its southern slope based on the CloudSat Cloud Profiling Radar 2B_GEOPROF dataset and the Aura Microwave Limb Sounder Level 2 cloud ice product onboard the Atrain constellation of Earth-observing satellites. It was found that the DCSs over the Tibetan Plateau and its southern slope have a higher main detrainment height (about 10-16 km) than other regions in the same latitude. The mean main detrainment heights are 12.9 and 13.3 km over the Tibetan Plateau and its southern slope, respectively. The cloud ice water path decreases by 16.8% after excluding the influences of DCSs, and the height with the maximum increase in cloud ice water content is located at 178 hPa (about 13 km). The main detrainment height and outflow horizontal range are higher and larger over the central and eastern Tibetan Plateau, the west of the southern slope, and the southeastern edge of the Tibetan Plateau than that over the northwestern Tibetan Plateau. The main detrainment height and outflow horizontal range are lower and broader at nighttime than during daytime.

关键词： main detrainment height deep convection systems Tibetan Plateau and its southern slope A-train

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Optical Properties of Cirrus Transition Zones over China Detected by CALIOP

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Journal of Meteorological Research 2017年第3期31卷 576-585页

作者： hongke cai Yunfei FU Quanliang CHEN Xiao FENG Xin TIE Ranting TAO Kepiao XU School of Atmospheric Science Chengdu University of Information Technology/Plateau Atmospheric and Environment Laboratory of Sichuan Province School of Earth and Space Sciences University of Science and Technology of China

A transition zone near cirrus lateral boundaries can be detected by CALIOP （cloud-aerosol lidar with orthogonal polarization）. In the present study, for such transition zones over China, a number of optical properties, such as the backscatter coefficient and depolarization ratio, showed transitional characteristics between cirrus and clear sky. The stepped horizontal profile showed sharp changes in particle number and morphology between cirrus clouds and clear sky. The color ratio, however, was unable to show cirrus transition features because of the low signal-to-noise ratio. Typical ice particles presented a color ratio of 0.55-1.25 and a depolarization ratio of greater than 0.12, which were significantly higher than those of clear sky. Therefore, optical properties in transition took the form of stepwise hori- zontal profiles. The proportion of typical-featured particles also demonstrated a stepped horizontal profile similar to the optical characteristics, but the relationship between the proportion and the optical characteristics was not uniform in the cirrus clouds, transition zone, and clear sky. Therefore, the optical changes in the transition zone were caused by not only the change in particle concentration, but also the change in the particles themselves. The probability dens- ity distribution of the transition-zone widths showed a positive skewness distribution, and transition zones with widths of 3-5 km occurred most frequently. Overall, transition-zone width decreased with increasing temperature and increased with increasing vertical and horizontal wind speeds. This trend demonstrated independence with the direc- tion of the vertical and horizontal winds. These observations implied that the transitional features were caused by ma- terial exchange, such as entrainment and turbulent transport, near the cirrus lateral boundaries, and by the phase trans- formation of particles, such as sublimation.

关键词： cirrus transition zone lidar temperature wind speed

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The tropical Pacific cold tongue mode and its associated main ocean dynamical process in CMIP5 models

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Earth and Planetary Physics 2019年第5期3卷 400-413页

作者： Yang Li QuanLiang Chen JianPing Li WenJun Zhang MinHong Song Wei Hua hongke cai XiaoFei Wu College of Atmospheric Science Plateau Atmosphere and Environment Key Laboratory of Sichuan ProvinceChengdu University of Information TechnologyChengdu 610225China Key Laboratory of Physical Oceanography-Institute for Advanced Ocean Studies Ocean University of China and Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory of Meteorological Disaster of Ministry of EducationNanjing University of Information Science and TechnologyNanjing 210044China

The cold tongue mode(CTM),which represents the out-of-phase relationship in sea surface temperature anomaly(SSTA)variability between the Pacific cold tongue region and elsewhere in the tropical Pacific,shows a long-term cooling trend in the eastern equatorial *** this study,we investigate how well the CTM is reproduced in historical simulations generated by the 20 models considered in Phase 5 of the Coupled Model Intercomparison Project(CMIP5).Qualitatively,all 20 models roughly capture the cooling SSTA associated with the ***,a quantitative assessment(i.e.,Taylor diagrams and the ratio of the trend between the simulations and observations)shows that only five of these 20 models(i.e.,CESM1-CAM5,CMCC-CM,FGOALS-g2,IPSL-CM5B-LR,and NorESM1-M)can reproduce with useful accuracy the spatial pattern and long-term trend of the *** find that these five models generally simulate the main ocean dynamical process associated with the *** is,these models adequately capture the long-term cooling trend in the vertical advection of the anomalous temperature by the mean *** conclude that the performance of these CMIP5 models,with respect to simulations of the long-term cooling trend associated with the vertical advection,and the related long-term decreasing trend of the vertical gradient of the oceanic temperature anomaly,can play an important role in successful reproduction of the CTM.

关键词： tropical Pacific La Nina-like cold tongue mode ocean dynamical process CMIP5

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The first two leading modes of the tropical Pacific and their linkage without global warming

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Earth and Planetary Physics 2019年第2期3卷 157-165页

作者： Yang Li QuanLiang Chen XiaoRan Liu Nan Xing ZhiGang Cheng hongke cai Xin Zhou Dong Chen XiaoFei Wu MingGang Li College of Atmospheric Science Plateau Atmosphere and Environment Key Laboratory of Sichuan ProvinceChengdu University of Information Technology State Chongqing Climate Center Beijing Meteorological Service

A discrepancy remains in the first two leading empirical orthogonal function(EOF) modes of the tropical Pacific sea surface temperature anomaly(SSTA) based on observations since the 1980s. The EOF1 mode, representing the El Ni?o-Southern Oscillation(ENSO), is a robust result. However, the EOF2 features either El Ni?o Modoki(EM) or ENSO evolution during different periods, which is probably associated with the impacts of global warming. The underlying question is what the EOF2 mode of the tropical Pacific would be without global warming. Using the CMIP5 preindustrial scenario to exclude the influence of global warming, we find that the EOF1 mode of the tropical Pacific SSTA represents ENSO and that the EOF2 mode is not EM. According to the lead–lag correlation between the ENSO and EOF2 modes, the linkage between these two modes is as follows: …El Ni?o → EOF2 → La Ni?a →–EOF2 → El Ni?o…. By analyzing the evolution of sea surface temperature, surface wind, and subsurface ocean temperature anomalies, we find the mechanism linking the ENSO and EOF2 modes is the air–sea interaction associated with the ENSO cycle. This result suggests that the EOF2 mode represents an aspect of ENSO evolution under preindustrial conditions. Therefore, this study further indicates that the EM is probably due to the influence of global warming.

关键词： El Nino-Southern Oscillation(ENSO) ENSO evolution global warming air-sea interaction

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器官系统整合课程消化系统疾病双语教学实践与探索

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中国继续医学教育 2023年第19期15卷 6-9页

作者：蔡洪科李洋重庆医科大学附属第二医院胃肠外科重庆400010

以器官系统为中心的教学是医学教育改革的重要方向,重庆医科大学是国内较早开展器官系统整合课程的高校之一,为了培养医学复合型人才并响应教育部在高校开展双语教学的要求,本校不断推进器官系统整合课程的双语教学,但器官系统整合课程... 详细信息

以器官系统为中心的教学是医学教育改革的重要方向,重庆医科大学是国内较早开展器官系统整合课程的高校之一,为了培养医学复合型人才并响应教育部在高校开展双语教学的要求,本校不断推进器官系统整合课程的双语教学,但器官系统整合课程双语教学面临诸多困难与挑战。通过对重庆医科大学2018级“5+3”临床医学、儿科学专业的74名学生进行医学整合课程消化系统疾病双语教学问卷调查,结果显示71.6%(53/74)的学生已通过大学英语六级考试(College English Test Band 6,CET-6)或托福(Test of English as a Foreign Language,TOEFL)、研究生入学考试(Graduate Record Examination,GRE)。学生对双语教学的认可度、任课教师的双语教学水平较低,在无配套双语教材的情况下学生课前预习准备较差,这些因素均会影响双语教学质量。本校通过提高学生双语学习的积极性,加强双语教学师资建设,改革教学方法及手段,建设配套双语教学教材等,从而提高了医学整合课程消化系统疾病双语教学质量。

关键词：器官系统整合课程消化系统疾病教学改革医学教育双语教学教学质量

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大渡河流域逐日降雨数据融合的误差分析

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成都信息工程大学学报 2022年第6期37卷 683-689页

作者：陈媛董丹丹申飙蔡宏珂国能大渡河大数据服务有限公司四川成都610041 成都信息工程大学四川成都610225 重庆美天科技有限公司四川成都401120

为有效结合不同来源降雨资料的优势,发展多源降雨融合技术,采用数据融合方法,生成融合逐日降雨数据(以下称为Grid数据),再与气象观测站点资料、ERA5和NCEP2格点资料进行误差对比,探讨Grid数据在大渡河流域的适用性。结果表明:(1)Grid数... 详细信息

为有效结合不同来源降雨资料的优势,发展多源降雨融合技术,采用数据融合方法,生成融合逐日降雨数据(以下称为Grid数据),再与气象观测站点资料、ERA5和NCEP2格点资料进行误差对比,探讨Grid数据在大渡河流域的适用性。结果表明:(1)Grid数据基本能完整展示大渡河流域的日均降雨分布,总体的、各区域内的降雨分布与观测数据展示出的分布规律基本吻合;(2)从插值站点来看,Grid数据的降雨量量级与观测数据差距小,总体的、各区域内的最大降雨量和最小降雨量与观测数据接近,表现优于ERA5和NCEP2数据;(3)从标准差、均方根误差来看,Grid数据的误差要明显小于EAR5和NCEP2数据;(4)从2008-2018年全流域、1~4分区的面雨量时间序列来看,Grid数据与观测数据较ERA5和NCEP2数据更接近。综上,Grid融合数据能较好地反映大渡河流域实际降雨情况。

关键词：气象学气象数据处理与方法数据融合方法降雨分布特征大渡河流域

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微RNA-194参与结直肠癌细胞上皮-间质转化及迁移和侵袭的作用机制探讨

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肿瘤 2016年第3期36卷 280-287页

作者：蔡洪科陈茜王继见邓甬川重庆医科大学附属第二医院胃肠外科重庆400010 重庆医科大学分子医学与肿瘤研究中心重庆400016 浙江大学医学院附属第二医院肿瘤外科浙江杭州310009

目的 :观察微RNA-194(micro RNA-194,mi R-194)在结直肠癌细胞侵袭和迁移过程中的作用,并探讨其参与细胞上皮-间质转化的作用机制。方法 :将携带mi R-194基因的质粒载体转染结直肠癌SW480细胞,构建稳定高表达mi R-194的细胞系mi R-194-4... 详细信息

目的 :观察微RNA-194(micro RNA-194,mi R-194)在结直肠癌细胞侵袭和迁移过程中的作用,并探讨其参与细胞上皮-间质转化的作用机制。方法 :将携带mi R-194基因的质粒载体转染结直肠癌SW480细胞,构建稳定高表达mi R-194的细胞系mi R-194-480,并观察该细胞的形态学变化。采用MTT法、细胞划痕愈合实验和Transwell迁移及侵袭实验分别观察mi R-194-480细胞的增殖、迁移和侵袭能力;同时,采用实时荧光定量PCR和蛋白质印迹法分别检测mi R-194高表达对上皮-间质转化相关分子表达水平的影响。结果 :高表达mi R-194的结直肠癌mi R-194-480细胞系构建成功,细胞由之前的扁圆形转变为梭形,发生明显的间质性改变。mi R-194质粒转染后,mi R-194-480细胞的增殖能力并未见明显变化(P>0.05),但细胞迁移和侵袭能力却明显增强(P值均<0.001)。mi R-194高表达能够上调基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)和波形蛋白(vimentin)的表达水平(P<0.05,P<0.001),而E-钙黏蛋白(E-cadherin)表达明显下调(P<0.01)。结论 :mi R-194通过调节MMP-2、E-cadherin和vimentin的表达,参与结直肠癌细胞的上皮-间质转化,从而明显提高结直肠癌细胞的迁移和侵袭能力。

关键词：结直肠肿瘤微RNAs 肿瘤转移肿瘤浸润 MiR-194 上皮-间质转化

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六个气候系统模式对西南地区2m温度的预报检验分析

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高原山地气象研究 2022年第1期42卷 77-84页

作者：蔡宏珂郑嘉雯毛雅琴衡志炜曾琳成都信息工程大学大气科学学院/高原大气与环境四川省重点实验室成都610225 广东省广州市气象台广州511430 中国气象局成都高原气象研究所/高原与盆地暴雨旱涝灾害四川省重点实验室成都610072

通过分析BCC_CSM1.1m、ECMWF_SYSTEM5、NCEP_CFSv2、FGOALS_f、FGOALS_s2、PCCSM4气候模式的模式初始误差、空间相关系数和时间距平相关系数,评估国内外6种气候预测模式在西南地区的预测能力。结果表明:FGOALS_s2和ECMWF_SYSTEM5模式的... 详细信息

通过分析BCC_CSM1.1m、ECMWF_SYSTEM5、NCEP_CFSv2、FGOALS_f、FGOALS_s2、PCCSM4气候模式的模式初始误差、空间相关系数和时间距平相关系数,评估国内外6种气候预测模式在西南地区的预测能力。结果表明:FGOALS_s2和ECMWF_SYSTEM5模式的初始误差最大,FGOALS_f模式的最小。模式在西南地区西南部模拟2 m温度的初始误差较小,ECMWF_SYSTEM5模式在四川盆地东部的预测场均方根误差较小。ECMWF_SYSTEM5模式预报的空间相关系数最大(小)值随时间有所下降(上升),尤其是2016~2018年变化趋势较为明显,其产生原因可能与欧洲中心模式升级有关。采用ECMWF_SYSTEM5模式(西南和东部区域)和BCC_CSM1.1m模式(西北区域)预报的空间相关系数较高。随着预报时效的延长,各模式预报西南子区域的空间相关系数均呈先减后增的变化趋势;就东部子区域而言,BCC_CSM1.1m、NCEP_CFSv2和ECMWF_SYSTEM5模式预报的空间相关系数变化较小,其余各模式呈现单峰或双峰的变化特征;各模式对西北子区域的预报稳定度较高。从预报时效为1个月的时间距平相关系数水平分布看,各模式对西南区域东部的预报效果优于西部,这可能是西部地势较高且天气物理过程具有特殊性导致的。PCCSM4模式对高原区域预报效果较好,但对于地形起伏较大的区域,其预报效果仍然较差。采用FGOALS_s2和PCCSM4模式对西南子区域的预报效果较好,FGOALS_s2和ECMWF_SYSTEM5模式对西北子区域的预报效果较好,PCCSM4和NCEP_CFSv2模式对东部子区域的预报效果较好。从预报时效为1~3个月的时间距平相关系数变化趋势看出,各模式在预报时效为1个月的时间距平相关系数较高(低)的区域,其数值随预报时效的延长有下降(上升)的变化趋势。

关键词： 2 m温度季节预测预报技巧气候系统模式

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