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Symbolic Uses of the “Rain” in the Novel A Farewell to Arms
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作者 古明 马博 于丹 《科技信息》 2010年第14期564-564,566,共2页
A Farewell to Arms,one of Ernest Hemingway's master works,mainly tells us a love story between Henry,a volunteer ambulance driver and Catherine,a beautiful British nurse.They fall in love with each other.Unfortuna... A Farewell to Arms,one of Ernest Hemingway's master works,mainly tells us a love story between Henry,a volunteer ambulance driver and Catherine,a beautiful British nurse.They fall in love with each other.Unfortunately,their love turns out to be a tragedy with Catherine and their baby's death.In this tragic story,it seems that where there is "rain",there is disaster and uneasiness.Accordingly,this essay will talk about the symbolic uses of the "rain". 展开更多
关键词 rain DEATH PARTING GRIEF
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RAIN-128算法的中间相遇攻击 被引量:1
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作者 杜小妮 郑亚楠 +1 位作者 梁丽芳 李锴彬 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第1期327-334,共8页
RAIN是一族SPN结构的轻量级分组密码算法,该算法具有软硬件实现效率高、安_全性强等特点。中间相遇攻击被广泛应用于分组密码算法的安全性分析中。该文通过分析RAIN-128的结构特性和截断差分特征,利用差分枚举技术分别构造了4轮和6轮中... RAIN是一族SPN结构的轻量级分组密码算法,该算法具有软硬件实现效率高、安_全性强等特点。中间相遇攻击被广泛应用于分组密码算法的安全性分析中。该文通过分析RAIN-128的结构特性和截断差分特征,利用差分枚举技术分别构造了4轮和6轮中间相遇区分器,给出了8轮及10轮的中间相遇攻击。当攻击轮数为8轮时,预计算阶段的时间复杂度为2^(68)次8轮RAIN-128加密,存储复杂度为2^(75)bit,在线攻击阶段的时间复杂度为2^(109)次8轮加密,数据复杂度是2^(72)个选择明文;当攻击轮数为10轮时,预计算阶段的时间复杂度为2^(214)次10轮加密,存储复杂度为2^(219)bit,在线攻击阶段的时间复杂度为2^(109)次10轮加密,数据复杂度是2^(72)个选择明文,分析结果显示,RAIN-128可以抵抗中间相遇攻击,并具有较高的安全冗余。 展开更多
关键词 分组密码 rain-128 中间相遇攻击 差分枚举技术
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Effect Evaluation of CBL Combined with Rain Classroom Teaching Method in Medical Statistics
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作者 Man Luo Xiaofang Zhang Wei Liu 《Open Journal of Applied Sciences》 2024年第5期1204-1213,共10页
Objective: To explore the application effect of CBL combined with rain classroom teaching method in medical statistics courses. Methods: The undergraduate students of medical imaging technology in 2019 and 2020 in a u... Objective: To explore the application effect of CBL combined with rain classroom teaching method in medical statistics courses. Methods: The undergraduate students of medical imaging technology in 2019 and 2020 in a university were selected as the research objects. A cluster sampling method was used to select 79 undergraduate students from 2019 in the control group and 75 undergraduate students from 2020 in the experimental group. Traditional teaching method and CBL combined with rain classroom teaching method was used in the control group and experimental group respectively. The final examination scores of the two groups were compared. In experimental group, the correlation between the average score in the rain classroom and the final examination score was tested, and the teaching effect was evaluated. Results: The average score of final examination in experimental group and control group was 79.13 ± 10.32 points and 71.54 ± 14.752 points, respectively, which had a statistically significant difference (Z = 2.586, P = 0.012);the final examination scores of the students in the experimental group were positively correlated with the average scores of the rain classroom (r = 0.372, P = 0.001), and the proportion of satisfaction in the experimental group was 94.7%. Conclusion: The CBL combined with rain classroom teaching method can improve the teaching effectiveness of medical statistics courses. 展开更多
关键词 rain Classroom CBL Medical Statistics
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基于“雨课堂”的植物生理学混合式教学设计与探索 被引量:3
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作者 肖继坪 杜晓翠 +2 位作者 陈疏影 董陈文华 李俊 《高教学刊》 2024年第1期103-106,共4页
随着多媒体工具和网络覆盖普及,基于互联网的在线教育愈加便捷,但其优势并未在高校的课程教学中得到体现和充分应用。该文针对植物生理学的学科特点和教学现状,充分利用线上教学资源,针对性地选择教学内容和方法,以学生为主体、教师为主... 随着多媒体工具和网络覆盖普及,基于互联网的在线教育愈加便捷,但其优势并未在高校的课程教学中得到体现和充分应用。该文针对植物生理学的学科特点和教学现状,充分利用线上教学资源,针对性地选择教学内容和方法,以学生为主体、教师为主导,基于“雨课堂”等教学平台进行线上线下混合式教学模式初探,以期利用有限的学时和丰富的线上教学资源,整合线上和线下教学的优势,通过有效的管理方式组织实施,为深化信息化教学改革、提高植物生理学的教学效果奠定基础。 展开更多
关键词 植物生理学 “雨课堂” 混合式教学 课程设计 组织实施
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基于雨课堂的SPOC+对分课堂的生理学混合式教学探索 被引量:1
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作者 关莉 闫福曼 +3 位作者 刘海梅 刘微 徐进文 张亚星 《中国中医药现代远程教育》 2024年第4期31-34,共4页
生理学是高等医药院校医药学及相关专业必修的基础课,其传统课堂教学存在“教得单调”“学得被动”“评得片面”等痛点问题。此研究建立异步小规模限制性在线课程(SPOC),作为学生课前、课后线上学习的主要资源;利用“雨课堂”平台进行... 生理学是高等医药院校医药学及相关专业必修的基础课,其传统课堂教学存在“教得单调”“学得被动”“评得片面”等痛点问题。此研究建立异步小规模限制性在线课程(SPOC),作为学生课前、课后线上学习的主要资源;利用“雨课堂”平台进行课前、课中、课后的教学管理。同时,在课堂教学设计中,引入“对分课堂”教学模式,将课堂时间和权力划分一半给学生,帮助学生完成知识的内化,使课堂成为线上线下融合、课前课中课后融合、教师教授与学生学习融合的关键环节,真正发挥教师的主导作用,体现学生的主体地位,从教师教学手段多样化、学生学习活动个体化、教学评价体系立体化等多方面提高教学质量和教育效果,为高等教育课堂教学改革开拓新思路、提供新素材。 展开更多
关键词 SPOC 雨课堂 对分课堂 生理学 教学改革
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基于雨课堂融合CBL教学法的传染病学见习课程建设及应用 被引量:1
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作者 李梅 党双锁 +4 位作者 贾晓黎 翟嵩 张欣 高宁 李亚萍 《中国高等医学教育》 2024年第1期136-138,共3页
建立基于雨课堂融合CBL教学法结合床旁教学的传染病见习课程模式并评价其应用效果。通过问卷调查+过程性评价+终结性评价的综合评价体系评价教学效果。研究结果表明,基于雨课堂的传染病见习课程模式有助于提高学生的学习兴趣和锻炼临床... 建立基于雨课堂融合CBL教学法结合床旁教学的传染病见习课程模式并评价其应用效果。通过问卷调查+过程性评价+终结性评价的综合评价体系评价教学效果。研究结果表明,基于雨课堂的传染病见习课程模式有助于提高学生的学习兴趣和锻炼临床思维能力,过程性评价联合终结性评价的评价体系能够较全面反映学生学习的过程与效果。因此,有必要进一步推广应用这种教学模式,并在实践的过程中持续改进。 展开更多
关键词 雨课堂 CBL 传染病学 见习课 教学模式
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新型教学工具“雨课堂”联合TBL教学法在儿科急救教学中的应用 被引量:1
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作者 邓莉莉 雷晔飞 +4 位作者 李君军 吴州丽 何骁 尹纾婧 张斯荻 《黑龙江医药科学》 2024年第2期24-27,共4页
目的:探讨新型教学工具“雨课堂”联合德莱尔(team-based learning,TBL)教学法在儿科急救教学中的应用。方法:选取2022年1月至2023年5月在郴州市第一人民医院儿科住培基地学习的医师86名作为研究对象。按照随机数字表法分为观察组(予以... 目的:探讨新型教学工具“雨课堂”联合德莱尔(team-based learning,TBL)教学法在儿科急救教学中的应用。方法:选取2022年1月至2023年5月在郴州市第一人民医院儿科住培基地学习的医师86名作为研究对象。按照随机数字表法分为观察组(予以新型教学工具“雨课堂”联合TBL教学法)与对照组(予以传统教学模式),每组各43名,对比理论知识、操作技能考核成绩、带教满意度、教学模式调查问卷评分及批判性思维态度倾向性量表(critical thinking disposition inventory-chinese version,CTDI-CV)。结果:观察组的理论知识、操作技能考核成绩均高于对照组(P<0.05)。观察组的激发学习兴趣、促进理论知识理解、提高思维水平、提高自主学习能力、提高临床应用能力、重视课前预习、重视课后复习、活跃课堂气氛、师生沟通交流及课程总体满意度占比高于对照组(P<0.05)。观察组的教学模式调查问卷评分高于对照组(P<0.05)。观察组的CTDI-CV评分均高于对照组(P<0.05)。结论:新型教学工具“雨课堂”联合TBL教学法在儿科急救教学中有利于提高医学生的临床思维能力和技能操作能力。 展开更多
关键词 “雨课堂”教学法 TBL教学法 儿科 急救教学
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Analysis, Variability and Rainfall Prediction in Sub-Saharan Africa: The Case of the Lake Guiers in Senegal
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作者 Abdou Arame Fall Saidou Ndao Aba Diop 《Open Journal of Ecology》 2023年第11期806-819,共14页
The aim of this article is to predict the rainfall evolution of a sub-Saharan area in which one of the most important freshwater resources is located: Lake Guiers. Characterized by short seasonal rains of three months... The aim of this article is to predict the rainfall evolution of a sub-Saharan area in which one of the most important freshwater resources is located: Lake Guiers. Characterized by short seasonal rains of three months, it experienced a long period of drought in the 1970s. We begin by analyzing the temporal distribution of the rainfall including the variability of the data, with a view to predicting a possible return. For this reason, we present here univariate modeling results of rainfall series collected on three stations in the area. The challenge lies in the adequacy of the parameters for the monthly rainfall series, which generates more or less significant forecast errors on the learning bases because of the missing data. This later motivated their conversion to moving average series. On the other hand, the normality of the latter seems to be rejected by the D’Agostino test. Student’s and Mann-Whitney’s tests confirmed the homogeneity. The autocorlograms show the presence of autoregressive terms in the data. Dickey-Fuller and Mann-Kendall tests reveal both trend and seasonality. The stationarity tests of Dickey-Fuller, Phillips-Perron and KPSS have shown that they are non-stationary. As a result, we did an ARIMA modeling method using the Box-Jenkins [1] method with the R software, which involves estimating model parameters, tests of significance, analysis of residualss, selection according to information criteria and forecasts. The results obtained during the learning-test phase showed a quasi-similarity of the base-tests in all the series except for that of Louga. 展开更多
关键词 Time Series rain TREND Stationarity RESIDUALS Model FORECAST
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雨养农业区黄芩轻简化膜间直播种植技术规程 被引量:1
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作者 米永伟 龚成文 +2 位作者 杨晓波 邵武平 张廷红 《寒旱农业科学》 2024年第2期189-192,共4页
为进一步推进甘肃省雨养农业区黄芩种植机械化、精量化和轻简化生产,结合多年的试验示范和生产实践,从范围、规范性引用文件、术语和定义、生产环境、栽培技术、田间管理、采收与产地加工等方面总结出了雨养农业区黄芩轻简化膜间直播种... 为进一步推进甘肃省雨养农业区黄芩种植机械化、精量化和轻简化生产,结合多年的试验示范和生产实践,从范围、规范性引用文件、术语和定义、生产环境、栽培技术、田间管理、采收与产地加工等方面总结出了雨养农业区黄芩轻简化膜间直播种植技术规程。 展开更多
关键词 黄芩 膜间直播 轻简化 技术规程 雨养农业区
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Analysis of Rainstorm Process in South China from September 7 to 8, 2022
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作者 Yiwei Wang 《Journal of Geoscience and Environment Protection》 2023年第8期161-167,共7页
Based on the NCEP data of the United States, a rainstorm process in South China during September 7 to 8, 2022 was studied. Synoptic method is a qualitative and empirical forecasting method. The results show that: In e... Based on the NCEP data of the United States, a rainstorm process in South China during September 7 to 8, 2022 was studied. Synoptic method is a qualitative and empirical forecasting method. The results show that: In early September 2022, the cold air behind the trough line from northeast China to North China can directly drive southward and invade South China from the east road. Typhoon Hinnamnor is located in the saddle field between the mainland subtropical high and the offshore subtropical high. It moves northward on the west side of the coastal subtropical high, affecting the Taiwan Island and the coastal areas of East China. During September 7-8, the wave trough of the 925 hPa Easterly wave was located near 110°E. Easterly jet existed in the southeast of South China. The center of the easterly jet was located to the east of Hainan Island, which could transport abundant water vapor from the sea surface to the sky over South China. The precipitable water in the whole layer of the atmosphere decreased from the southern coastal areas to the north, reaching more than 50 mm in southern China, of which most of the South China Sea, Hainan Island and parts of the western part of Guangdong Province exceeded 60 mm, providing sufficient water vapor supply. The circulation field with convergence at low level and divergence at high level is conducive to vertical uplift to form precipitation. 展开更多
关键词 South China Heavy rain Easterly Wave Subtropical High
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EICP与木质素联合改性粉土边坡抗雨蚀试验研究 被引量:1
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作者 张建伟 钱思羽 +3 位作者 王小锯 边汉亮 韩智光 石磊 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期70-76,共7页
通过设置6组试样,采用降雨试验,通过试样的表面侵蚀状况与冲蚀量、表面强度、碳酸钙含量的变化分析了改性后粉土边坡的抗雨蚀性能。试验结果表明:植物源酶诱导碳酸钙沉淀(EICP)与木质素联合改性试样并在表面喷洒EICP溶液后,试样表面完... 通过设置6组试样,采用降雨试验,通过试样的表面侵蚀状况与冲蚀量、表面强度、碳酸钙含量的变化分析了改性后粉土边坡的抗雨蚀性能。试验结果表明:植物源酶诱导碳酸钙沉淀(EICP)与木质素联合改性试样并在表面喷洒EICP溶液后,试样表面完整度更好,表面强度及碳酸钙含量更高,质量损失更小,抗雨蚀能力明显提高,与其他试样的平均值相比,边坡土体侵蚀量降低了75.0%,表面强度提高了33.8%,碳酸钙含量提高了235.2%;坡面喷洒EICP溶液可形成硬壳层,有效避免坡面侵蚀;木质素可为碳酸钙提供成核位点,使分布散乱的碳酸钙附着在木质素上,添加木质素后试样碳酸钙含量提高,且表面强度随碳酸钙含量提高而增大。 展开更多
关键词 植物源酶诱导碳酸钙沉淀(EICP) 木质素 粉土边坡 雨蚀 成核位点
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Characteristic Analysis of Short Time Heavy Rain in Yulin, China
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作者 Yiqing Xiao Qiyuan Hu +1 位作者 Pingyun Li Jing Yao 《Journal of Geoscience and Environment Protection》 2023年第9期165-175,共11页
National Centers for Environment Prediction (NCEP) reanalysis data, automatic observation data, FY-2E satellite data and Doppler radar data are used to analyze a short-time local heavy rain in Yulin city, Shaanxi, Chi... National Centers for Environment Prediction (NCEP) reanalysis data, automatic observation data, FY-2E satellite data and Doppler radar data are used to analyze a short-time local heavy rain in Yulin city, Shaanxi, China on August 7, 2018. The result shows that the strong convective weather occurred in peripheral subtropical high over west pacific, being caused by short wave disturbance, and surface convergence lines with positive pressure variation are corresponding to areas of short-time heavy precipitation. The degree of temperature change in cold pool caused by thunderstorm may decide the intensity of a short-time rainfall, and local topography plays an important role in extreme precipitation. Local water vapour accumulation and water vapour flux convergence in the middle and lower layers support adequate moisture condition in the process. Moving direction and development direction of mesocale convective cloud are in a line to develop the train effect, leading to local short-time heavy rain in Yulin city, Shaanxi, China. 展开更多
关键词 Short-Time rain Storm Precipitable Water Vapor Flux Divergence Train Effect
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海温异常对长江流域夏季典型旱涝的影响研究 被引量:1
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作者 张灵 熊开国 +1 位作者 郭广芬 张俊 《人民长江》 北大核心 2024年第4期118-124,共7页
为研究长江流域夏季旱涝特征及其与海温异常之间的关联性,基于中国326个气象站降水量、NCEP/NCAR再分析资料等,采用合成分析、EOF分解等方法,分析了长江流域夏季典型旱涝年的降水分布、同期大气环流及前期海温特征,并以2018年为例,初步... 为研究长江流域夏季旱涝特征及其与海温异常之间的关联性,基于中国326个气象站降水量、NCEP/NCAR再分析资料等,采用合成分析、EOF分解等方法,分析了长江流域夏季典型旱涝年的降水分布、同期大气环流及前期海温特征,并以2018年为例,初步揭示了2018年前期海温异常对大气环流的可能影响。结果表明:①长江流域夏季典型旱年,仅嘉陵江和岷沱江会表现出局部偏涝,全国为典型的Ⅰ类雨型,多雨区位于黄河流域及以北地区。前期冬季赤道太平洋表现出类拉尼娜的东冷西暖分布,同时黑潮区海温偏低,西风漂流区海温偏暖。受多海域协同作用,同期欧亚环流场上自西北向东南呈现出“+-+”三极型分布,东亚地区为自北向南“-+-”的EAP负位相。长江流域典型涝年,全国多为典型的Ⅱ类和Ⅲ类雨型,环流及海温呈现出相反特征。②2018年为典型的长江中下游偏旱年,仅在岷沱江降水偏多近3成,为历史第4多,与长江流域夏季降水的主模态正位相类似,解释方差达24%。③2018年前冬出现弱拉尼娜、春末夏初西风漂流区异常偏暖、NAT异常正位相,三者共同作用,使得东亚副热带西风急流偏北,东亚沿岸出现EAP负位相,大陆热低压明显偏强,东亚夏季风为1961年以来最强,同时副高脊线最北,造成夏季降水主雨带北推至华北、西北地区,岷沱江、嘉陵江异常多,而长江中下游异常少,为典型的Ⅰ类雨型。研究成果可为长江流域旱涝预测、水资源调度提供参考。 展开更多
关键词 夏季典型旱涝 海温异常 Ⅰ类雨型 拉尼娜 西风漂流区 长江流域
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Northeastern Tropical Atlantic SST and Sahel Rainfall Variability
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作者 Dahirou Wane Abdou Lahat Dieng +1 位作者 Coumba Niang Amadou T. Gaye 《Atmospheric and Climate Sciences》 2023年第4期431-454,共24页
The SST variability during the summer period in the northeastern tropical Atlantic region (NTA) is characterized by an alternation of warming/cooling which represents 87% of the total variability. The aim of this pape... The SST variability during the summer period in the northeastern tropical Atlantic region (NTA) is characterized by an alternation of warming/cooling which represents 87% of the total variability. The aim of this paper is to study the atmospheric responses as well as the precipitation associated with these oceanic conditions. Based on Reynolds’s SST from 1982 to 2019, a normalized Northern Tropical Atlantic index (NTAI) is computed into the region between 15° - 25°W;12° - 16°N and a composite analysis is then performed. It is shown that the NTAI is significantly correlated with the SST’s first principal component mode (PC1) in this region. Moreover, the composite of SST anomalies and atmospheric parameters exhibits a strong local ocean-atmosphere interaction which highly impacts the large-scale atmospheric circulation in West Africa, particularly in the western Sahel. An in-depth analysis shows that the atmospheric response to the warm (cold) SST is a cyclonic (anticyclonic) circulation in the lower layers near the West Africa Coast. This cyclonic (anticyclonic) circulation strengthens/reduces the moisture transport towards the continent in the low levels. In the middle layers of the atmosphere (500 hPa), the warm (cold) composite is associated with a decrease (increase) in the intensity of the African Easterly Jet (AEJ) whereas, in the upper atmosphere (200 hPa), the strengthening (weakening) of the Tropical Easterly Jet (TEJ) is observed. With regard to the composite precipitation field, a positive/negative SST anomaly is associated with significantly enhanced/reduced rainfall in the western Sahelian region. It is found that this relationship (correlation) increases as we are closer to the coasts. 展开更多
关键词 SST-rain Sahel rainfall Senegal rainfall Ocean-Atmosphere Interaction
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Pacific Sea Surface Temperature Effect Summer Rainfall in Huanghuai, Jianghuai Region in China
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作者 Tiantian Liu Xin Wang 《Open Journal of Applied Sciences》 2023年第8期1440-1445,共6页
Summer Precipitation in Eastern China was closely related to the global sea surface temperature field. In this paper, the impact of the main sea surface temperature anomaly on flood season precipitation in China’s Hu... Summer Precipitation in Eastern China was closely related to the global sea surface temperature field. In this paper, the impact of the main sea surface temperature anomaly on flood season precipitation in China’s Huanghuai and Jianghuai regions is examined as an external forcing factor for short-term climate prediction. Through analysis of global sea surface temperature anomalies and regional anomalies in Huanghuai and Jianghuai, a significant effect related to the main area, the North Pacific region, and the Nino3 corresponding index calculation is found. Various key areas are examined for their relevance, and finally, the mechanism of summer precipitation in two key zones, China’s Huanghuai and Jianghuai regions, is briefly discussed. The main implication is the prediction of season precipitation based on the external forcing signal of sea surface temperature anomaly in China’s Huanghuai and Jianghuai regions. 展开更多
关键词 Summer rainfall Sea Surface Temperature II rain Type RELATIVE
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基于河涌纳污能力的特大城市中心城区初期雨水截流标准
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作者 谭超 刘达 +2 位作者 黄本胜 刘美婷 罗志发 《水电能源科学》 北大核心 2024年第2期125-128,196,共5页
为有效控制和治理特大城市中心城区排水系统溢流的初期雨水污染,选取广州市猎德涌和石井河作为典型河涌,在对初期雨水水质及降雨特征进行分析的基础上,复核水域纳污能力,对比分析截流雨量与污染物削减效率,提出了初期雨水治理的截流标... 为有效控制和治理特大城市中心城区排水系统溢流的初期雨水污染,选取广州市猎德涌和石井河作为典型河涌,在对初期雨水水质及降雨特征进行分析的基础上,复核水域纳污能力,对比分析截流雨量与污染物削减效率,提出了初期雨水治理的截流标准。结果表明,广州市中心城区合流制区域的初雨截流标准宜为8~10 mm,分流制区域的取值宜为5~6 mm。研究结果可为广州市等特大城市中心城区初期雨水污染治理提供科学依据。 展开更多
关键词 特大城市 初期雨水 截流标准 纳污能力
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Enhancement of East African Monsoon Long Rainfall (March to May) Variability from Weekly to Annual Scale by Climatic Extremes
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作者 Jonah Kazora Weijun Zhu +3 位作者 Than Oo Kyaw Joseph Ndakize Sebaziga Frank Rusanganwa James Kagabo 《Atmospheric and Climate Sciences》 2023年第4期491-506,共16页
As global warming increasingly affects vulnerable regions such as Central East Africa, it is crucial to understand future changes in rainfall variability to reduce vulnerability. Despite the importance of rainfall var... As global warming increasingly affects vulnerable regions such as Central East Africa, it is crucial to understand future changes in rainfall variability to reduce vulnerability. Despite the importance of rainfall variability, it has received less attention compared to changes in mean and extreme rainfall. This study evaluates the amplification of synoptic (weekly) to annual variability of East African Monsoon (EAM) Long Rainfall (March to May) by climatic extremes. Using band-pass filtered daily rainfall data, we found that EAM rainfall variability is anticipated to increase by 20% - 60% across the region under global warming conditions. The majority of the intermodal variability in Long Rain EAM rainfall forecasting is explained by differences in mean rainfall. Our results show that the synoptic variability of Long Rain for EAM rainfall is likely to amplify, resulting in more extreme rainfall events and longer dry spells under global warming. This amplification is attributed to the warming of the Indian Ocean and the associated changes in atmospheric circulation patterns. The projected increase in synoptic to annual variability of Long Rain for EAM rainfall has significant implications for water resources management and agriculture in the region, challenging policymakers to develop adaptive strategies that can mitigate the impacts of these extreme events. This study emphasizes the potential impacts of projected climate changes in rainfall variability on the East African region at all periods and underscores the need for effective adaptation strategies to ensure sustainable development. 展开更多
关键词 Synoptic Variability East Africa Monsoon Long rain Global Warming Amplification
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不同类风场雨滴冲击荷载对输变电塔线体系动力响应的影响研究
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作者 王辉 戴根 张鑫 《应用力学学报》 CAS CSCD 北大核心 2024年第2期404-410,共7页
输变电塔体系遭受风雨耦合作用破坏时常将原因归于风荷载,忽略了雨荷载耦合激励的放大效应。针对某输电线路“一塔两线”体系模型,以数值方法模拟良态风雨场与湿下击暴流场的风雨时程荷载,分别对塔线体系进行动力响应分析,结果表明:降... 输变电塔体系遭受风雨耦合作用破坏时常将原因归于风荷载,忽略了雨荷载耦合激励的放大效应。针对某输电线路“一塔两线”体系模型,以数值方法模拟良态风雨场与湿下击暴流场的风雨时程荷载,分别对塔线体系进行动力响应分析,结果表明:降雨对输电塔线体系的响应,具有显著影响,随着雨强变大,塔线体系响应增大明显;在极值降雨条件下,湿下击暴流场塔顶位移增幅最大,在X向和Y向分别达到31.30%和33.93%;两种风雨场中塔顶位移及加速度功率谱密度均出现明显增幅,体系共振响应增强,塔身关键位置主材应力分别增大了11.64%、37.07%;在不同类风场中,强降雨时雨滴冲击对塔线体系产生的激励增大作用不可忽略。 展开更多
关键词 塔线体系 风雨荷载 良态风雨场 湿下击暴流 动力响应分析
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基于CAMM和CLDAS的黄淮海冬小麦成熟期连阴雨时空特征
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作者 邬定荣 高静 +5 位作者 姬兴杰 张溪荷 王培娟 杨建莹 马玉平 霍治国 《气象与环境科学》 2024年第1期1-9,共9页
利用黄淮海地区2008—2023年的CLDAS数据和同期65个农业气象观测站的冬小麦花期、成熟期观测数据,订正机理性中国农业气象模式(CAMM)中发育模块(RAM)的参数,评估模式对冬小麦成熟期的模拟精度,而后重构格点化的历年成熟期日期,统计成熟... 利用黄淮海地区2008—2023年的CLDAS数据和同期65个农业气象观测站的冬小麦花期、成熟期观测数据,订正机理性中国农业气象模式(CAMM)中发育模块(RAM)的参数,评估模式对冬小麦成熟期的模拟精度,而后重构格点化的历年成熟期日期,统计成熟期前6天后9天共16天的降水量和雨日数,随后基于连阴雨指标,研究连阴雨的时空分布特征。结果表明:(1)RAM模式对冬小麦成熟期具有较好的模拟能力,各站RMSE平均值为2.28±0.46 d,模拟值与实测值的R2为0.915。(2)黄淮海地区冬小麦成熟期降水量和雨日数均呈南北两端高中间低的空间分布格局,区域平均降水量为8.8~84.6 mm,平均值为31.9 mm,雨日数为1.0~9.1天,平均值为5.4天。(3)2008—2023年连阴雨灾害波动较大,其中2009、2013、2018和2023年较为严重,大致呈4~5年发生一次的周期性规律,且灾情呈加重的趋势。(4)连阴雨灾害在黄淮海地区北部很少发生,河北和山东交界处偶发,灾害高发重发区主要集中在河南省,尤其是郑州以南的驻马店和信阳一带最为严重,发生频率约为5年一遇,持续天数多在9天以上。 展开更多
关键词 连阴雨 黄淮海地区 冬小麦 发育模式 格点资料
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利用DQCT实现2018年8月超历史极值暴雨的高质量模拟
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作者 李博 李帅康 +3 位作者 陈超 钟水新 华灯鑫 徐波 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期31-39,共9页
构建较全面的双级质量控制技术(DQCT).利用中尺度天气预报模式(WRF)对2018年8月下旬华南地区一次超历史极值的暴雨过程进行高分辨率数值模拟,并用DQCT评判暴雨的模拟效果.结果表明,在暴雨形势背景场中用WRF成功模拟大尺度季风风场、西... 构建较全面的双级质量控制技术(DQCT).利用中尺度天气预报模式(WRF)对2018年8月下旬华南地区一次超历史极值的暴雨过程进行高分辨率数值模拟,并用DQCT评判暴雨的模拟效果.结果表明,在暴雨形势背景场中用WRF成功模拟大尺度季风风场、西南暖湿气流与低压交汇过程,并准确复制了造成高潭镇极端降雨的中尺度对流系统.总降雨量中的中γ尺度极值暴雨中心模拟得较为准确.该模式在24 h降雨量模拟中成功复制了暴雨中心的演变过程;在6 h降雨量模拟中较好地再现了中γ尺度雨带的演变过程.在暴雨重灾区高潭镇1 h降雨量演变过程的模拟中,总体降雨趋势与实况吻合较好.定性分析结果同步得到定量指标的验证. 展开更多
关键词 超历史极值暴雨 中γ尺度雨带 数值模拟 双级质量控制技术
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