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PARTITION OF SEASON BASED ON MULTIELEMENTS AND THE DECADAL CHANGE OF SEASON DURATION IN CHINA

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Journal of Tropical Meteorology 2019年第3期25卷 385-398页

作者： WANG Zheng ZHI Rong WANG Yu feng guo-lin College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000 China Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081 China

Using the multielements similarity measurement method and 1950-2017 NCEP/NCAR gridded daily reanalysis datasets, we analyzed season duration in China during 1950-2016, and we defined the element with maximum absolute sensitivity as the key impact element at each point using the sensitivity analysis method. The decadal change of season duration and its key impact element before and after 1980 were studied. The results indicated obvious meridional and zonal differences in the distribution of season duration for the 67-year average, and that the key impact element has the same distribution characteristics as season duration. In addition, complementary relationships were found between the durations of spring and summer, autumn and winter, and the cold and warm seasons. Among them, the complementary relationship between the durations of spring and summer was strongest and the regions of complementarity were numerous. The complementary regions of autumn and winter durations were found mainly in western China. In the cold and warm seasons, the complementary regions were widespread and the complementary relationship was generally weak. Comparison of the periods before and after 1980 revealed an east-west difference in the interdecadal variation of season duration. Interdecadal variation in spring and summer was found concentrated in northern and western regions, while that in autumn and winter was concentrated in the western region. Areas of significant interdecadal variation of the key elements were found concentrated in northern and western regions,corresponding well to the areas of significant interdecadal variation of season duration.

关键词： multielements similarity measurement method season duration key impact element decadal change

A STUDY OF THE WINTER-WINTER RECURRENCE MECHANISM OF THE TEMPERATURES IN NORTHERN EAST ASIA

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Journal of Tropical Meteorology 2018年第1期24卷 49-59页

作者： WANG Xiao-juan QIAO Shao-bo feng guo-lin College of Physics and Electronic Engineering Changshu Institute of Technology Changshu Jiangsu 215500 China Department of Atmospheric Sciences Lanzhou University Lanzhou 730000 China National Climate Center China Meteorological Administration Beijing 100081 China

In this study, the winter-summer-winter seasonal variation characteristics of the atmospheric temperature in northern East Asia(NEA) during the past 60 years are analyzed. The results revealed a type of new seasonal variation mechanism of temperature: winter-winter recurrence(WWR). This study initially discussed the formation mechanism of WWR from the angle of the relationship between the WWR and the atmospheric internal factors and external *** main conclusions are summarized as follows:(1) The winter-summer-winter continuous variation of the AO anomaly index has consistent characteristics with the atmospheric variation of the WWR in the NEA, and their 60-year correlation coefficient reaches 0.43, passing the 95% significance level. It is indicated that the seasonal anomaly of the AO has a certain influence on the WWR;(2) Overall, the PDO maintains a negative phase in the negative WWR years,while it displays the opposite feature in the positive WWR years. The negative(positive) anomaly of PDO is favourable to the occurrence of sustainable low(high) temperatures in the NEA, and may be the important external driving factor for motivating the WWR in the NEA;(3) The binary regression, based on the PDO and AO indexes successfully reproduces the curve of T_(WWR-HG), which is significantly correlated with the WWR index TWWR, and can reproduce the time-height profile of the WWR characteristics from 400 to 1,000 hPa. Therefore, it is concluded that the WWR of the atmospheric temperatures in the NEA is the result of the combined action of the PDO and AO.

关键词： recurrence index mechanism winter-winter recurrence synthesis analysis combined action

Spatial-Temporal Characteristics of Regional Extreme Low Temperature Events in China during 1960-2009

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Advances in Climate Change Research 2012年第4期3卷 186-194页

作者： WANG Xiao-Juan GONG Zhi-Qiang REN Fu-Min feng guo-lin Department of Atmospheric and Sciences Lanzhou University College of Physics and Electronic Project Changshu Institute of Technology National Climate Center China Meteorological Administration

An objective identification technique is used to detect regional extreme low temperature events （RELTE） in China during 1960-2009. Their spatial-temporal characteristics are analyzed. The results indicate that the lowest temperatures of RELTE, together with the frequency distribution of the geometric latitude center, exhibit a double-peak feature. The RELTE frequently happen near the geometric area of 30°N and 42°N before the mid-1980s, but shifted afterwards to 30°N. During 1960-2009, the frequency~ intensity, and the maximum impacted area of RELTE show overall decreasing trends. Due to the contribution of RELTE, with long duratioh and large spatial range, which account for 10% of the total RELTE, there is a significant turning point in the late 1980s. A change to a much more steady state after the late 1990s is identified. In addition, the integrated indices of RELTE are classified and analyzed.

关键词： regional extreme low temperature events spatial-temporal features turning point frequency distribution

Clinical Study of Combining Chemotherapy of Oxaliplatin or 5-Fluorouracil/Leucovorin with Hydroxycamptothecine for Advanced Colorectal Cancer

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Chinese Journal of Clinical Oncology 2009年第2期6卷 117-123页

作者： Yuanjue Sun Hui Zhao Yaowu guo feng lin lina Tang Yang Yao Department of Medical Oncology The Sixth People's Hospital of Shanghai Jiaotong University Shanghai 200233 China

OBJECTIVE To estimate effects, survival rate after the short-time efficacy, side the treatment of combining chemotherapy of oxaliplatin or 5-fluorouracil/leucovorin with hydroxycamptothecine （HCPT） for the patients with advanced colorectal cancer. METHODS From January 2002 to November 2005, 59 patients with advanced colorectal cancer confirmed by pathology were enrolled into this study in the department of medical oncology, in the Sixth People＇s Hospital of Shanghai Jiaotong University, Shanghai. Patients＇ characteristics in two groups were similarly confirmed by statistic. All 37 patients in OH group received oxalip21atin （130 mg/m^2 d1） plus hydroxycamptothecine （6 mg/m d1-4）, and all 22 patients in the HLF group received hydroxycamptothecine （6 mg/m^2 d1-4） plus leucovorin （300 mg d1-5） and 5-fluorouracil （0.375 g/m^2 d1-5）. The regimens in both groups were 21-day cycle that was repeated three weeks. The side effects were evaluated. The efficacy was estimated after two cycles of chemotherapy for each patient. RESULTS The efficacy of the treatment in the OH group with 37 patients and in the HLF group with 22 patients was estimated. The overall response rate （CR ＋ PR） was 32.4% in the OH group and 22.7% in the HLF group. There was no complete response （CR） and there was no statistical significantly difference （%2= 0.876, P = 0.704） in two groups. The 1-year survival rate was 30.98% in the OH group and 15.02% in the HLF group, and it had no significant difference between the two groups. The median PSF and OS were 5.83 months and 11.17 months in the OH group vs. 7.40 months and 10.48 months in the HLF group, and it had no significant differences between the two groups （P 〉 0.05）. The major side effects of grade III and IV in the two groups were myelosuppression and gastrointestinal reactions. The statistically significant difference in side effects appeared in leukopenia （χ^2= 17.173, P = 0.001）, nausea/vomiting （χ^2= 6.426, P = 0.039）, diarrhea （χ^2= 16.245, P =

关键词： oxaliplatin hydroxycamptothecine 5-fluorouracil colorectal cancer.

考虑内阻尼的梁结构耦合点处近场耗散功率分析

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振动与冲击 2013年第15期32卷 126-129,137页

作者：郑国涛国凤林上海交通大学船舶海洋与建筑工程学院上海200240

以考虑结构内阻尼系数的Euler-Bernoulli梁为理论基础,建立了以任意角度耦合的简单三叉梁结构波动方程,根据耦合点处平衡条件和连续性条件得到了在分别给定弯曲波激励和纵向波激励情况下近场波的幅值,由于内阻尼系数的引入,近场项将消... 详细信息

以考虑结构内阻尼系数的Euler-Bernoulli梁为理论基础,建立了以任意角度耦合的简单三叉梁结构波动方程,根据耦合点处平衡条件和连续性条件得到了在分别给定弯曲波激励和纵向波激励情况下近场波的幅值,由于内阻尼系数的引入,近场项将消耗功率,根据振动波幅和振动功率之间的关系求得到耦合点处近场耗散功率系数,算例研究了内阻尼系数、耦合角度和激励频率对一种特定三叉梁近场耗散功率系数的影响,得到了一些至关重要的结论,对耦合梁结构振动设计有着重要的指导意义。

关键词：内阻尼系数振动功率近场耗散功率三叉梁

与黏性电介质液体接触的压电材料中B-G波的传播

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上海交通大学学报 2009年第8期43卷 1262-1266页

作者：宋煜国凤林上海交通大学工程力学系上海200240

采用严格的界面电学边界条件导出了显式形式的频散关系,并对PZT-5H压电陶瓷进行了数值计算.计算结果表明:衰减随着液体的黏性系数、液体密度和波的频率的增加而增大;当液体的介电常数较大时,穿透深度变小,衰减变大.

关键词： B-G波压电材料黏性液体频散关系穿透深度

中国夏季大气水分循环特征及再分析资料对比分析

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物理学报 2014年第24期63卷 489-501页

作者：苏涛封国林兰州大学大气科学学院兰州730000 国家气候中心中国气象局气候研究开放实验室北京100081

大气水分循环过程耦合了降水、蒸发、水汽输送等多个环节.本文利用ERA-Interim与MERRA再分析资料,研究了中国1979—2012年夏季大气水分循环的时空变化特征及其对全球气候变化的响应,并对两套再分析资料在中国地区的适用性进行了评估.结... 详细信息

大气水分循环过程耦合了降水、蒸发、水汽输送等多个环节.本文利用ERA-Interim与MERRA再分析资料,研究了中国1979—2012年夏季大气水分循环的时空变化特征及其对全球气候变化的响应,并对两套再分析资料在中国地区的适用性进行了评估.结果表明:1)中国夏季降水、蒸发、可降水量均自东南沿海地区向西北内陆递减;降水与蒸发相互联系、相互制约,由于不同地区下垫面物理条件的差异,它们之间同时存在正、负反馈的影响机制,可降水量主要集中在地面至700 h Pa高度,约占总量的75%;2)近34年大气水分循环显著变化的区域主要集中在西部和东北地区,西部内陆地区可降水量显著增加,北方大部分地区纬向水汽输送通量显著减小,西北北部地区经向水汽输送通量显著增大,蒸发量与水汽输送的气候变化可能是造成可降水量增加的主要原因;3)Interim与MERRA资料对降水量时空变化特征的再现能力要优于蒸发量,此外,它们对降水与蒸发气候变化趋势的模拟结果差别较大,使用时应该慎重;两套资料对可降水量与水汽输送通量的时空变化特征以及气候变化趋势的模拟比较一致,可信度较高;4)Interim资料对西南、东南以及东北区域夏季水循环均有较好的描述能力;而MERRA资料更适用于研究西南和西北区域的水汽收支情况.

关键词：大气水分循环再分析资料大气水汽收支气候变化趋势

氢扩散与裂纹尖端应力场耦合效应的有限元分析

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表面技术 2018年第6期47卷 240-245页

作者：张显国凤林上海交通大学船舶海洋与建筑工程学院上海200240

目的研究氢鼓包形成过程中应力诱导下氢原子的扩散聚集行为,并考虑氢原子扩散聚集后对裂纹尖端区域应力场的影响,探究裂纹尖端区域氢浓度、氢气压强、应力强度因子随时间的演化历程。方法采用有限元软件ABAQUS,通过一个完全耦合分析,探... 详细信息

目的研究氢鼓包形成过程中应力诱导下氢原子的扩散聚集行为,并考虑氢原子扩散聚集后对裂纹尖端区域应力场的影响,探究裂纹尖端区域氢浓度、氢气压强、应力强度因子随时间的演化历程。方法采用有限元软件ABAQUS,通过一个完全耦合分析,探究氢扩散与裂纹尖端区域应力场相互影响的动态过程。借助于断裂力学中的裂纹扩展判据判定氢鼓包是否会继续向前扩展。结果在应力诱导作用下,氢原子源源不断地向裂纹尖端高应力区域聚集,裂纹尖端区域的氢浓度、氢压、应力强度因子随时间呈指数型增长。结论在浓度梯度作用下,氢原子会向材料内部扩散。氢压引起的应力场会促进氢原子的扩散聚集行为,且应力场越大,促进作用越明显,使得缺陷处的氢浓度不断增大,氢压也就越来越大。当应力强度因子达到裂纹起裂的临界值时,就会导致开裂,形成氢鼓包,如此循环往复,直至氢鼓包开裂。

关键词：氢扩散应力诱导扩散完全耦合分析氢鼓包裂纹扩展

PROPAGATION OF BLEUSTEIN-GULYAEV WAVE IN A PIEZOELECTRIC CRYSTAL IN CONTACT WITH VISCOUS CONDUCTIVE LIQUIDS

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PROPAGATION OF BLEUSTEIN-GULYAEV WAVE IN A PIEZOELECTRIC CRY...