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Identification of coastal water quality by multivariate statistical techniques in two typical bays of northern Zhejiang Province,East China Sea

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Acta Oceanologica Sinica 2017年第2期36卷 1-10页

作者： YE Ran LIU Lian WANG Qiong YE Xiansen CAO Wei HE Qinyan cai yanhong Marine Environmental Monitoring Centre of Ningbo State Oceanic Administration (SOA) School of Marine Sciences Ningbo University

The Hangzhou Bay（HZB） and Xiangshan Bay（XSB）, in northern Zhejiang Province and connect to the East China Sea（ECS） were considerably affected by the consequence of water quality degradation. In this study, we analyzed physical and biogeochemical properties of water quality via multivariate statistical techniques. Hierarchical cluster analysis（HCA） grouped HZB and XSB into two subareas of different pollution sources based on similar physical and biogeochemical properties. Principal component analysis（PCA） identified three latent pollution sources in HZB and XSB respectively and emphasized the importance of terrestrial inputs, coastal industries as well as natural processes in determining the water quality of the two bays. Therefore, proper measurement for the protection of aquatic ecoenvironment in HZB and XSB were of great urgency.

关键词： coastal water quality Hangzhou Bay Xiangshan Bay hierarchical cluster analysis principal component analysis latent pollution sources

Phytoplanktonic biogeography in the subtropical coastal waters,East China Sea along intensive anthropogenic stresses: roles of environmental versus spatial factors

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Acta Oceanologica Sinica 2023年第4期42卷 103-113页

作者： Ran Ye Haibo Zhang Yige Yu Qing Xu Dandi Shen Min Ren Lian Liu yanhong cai Marine Environmental Monitoring Centre of Ningbo Ningbo 315012China

Understanding the relative roles of local environmental effects and spatial effects on phytoplankton community is of essential importance to study the biogeography of them at regional scale. However, the determinants that driving the biogeography of phytoplankton communities in the coastal area of northern Zhejiang still remained unclear. We surveyed phytoplankton community compositions in water columns associated with environmental and spatial influences across five subzones that geographically covering this region over four seasons. Diatoms and dinoflagellates were recorded as the main dominant groups and Coscinodiscus oculs-iridis, Coscinodiscus jonesianus, and Skeletonema costatum, were identified as the major abundant species existing in all *** structured environmental conditions, rather than pure spatial or environmental factors, substantially shaped the biogeography of phytoplankton community, with the former mainly comprised of water temperature,dissolved oxygen, phosphate, pH, and salinity, and the latter referring to a non-negligible factor. This study was the first integrated research that combining environmental filtering with spatial factors in structuring phytoplankton communities at a complete tempo-spatial scale. Our results may facilitate to the further study of harmful algal blooms early-warning in this region.

关键词： biogeography of phytoplankton community environmental factors spatial factors coastal area of northern Zhejiang

Ecological thresholds of phytoplankton community across environmental gradients in the harmful algal blooms-frequently-occurring,subtropical coastal waters,East China Sea

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Acta Oceanologica Sinica 2021年第6期40卷 100-110页

作者： Ran Ye Chunying Ge Qiong Wang Qing Xu Guofeng Xu Yongkang Yan Mingli Qin yanhong cai Yuejun Fei Marine Environmental Monitoring Centre of Ningbo Ningbo 315012China

Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic *** study provided insights into the relationships concerning ecological thresholds of phytoplankton communities and individual taxon in response to environmental changes in coastal waters of northern Zhejiang Province,East China *** demonstrated that there existed seasonal variations of phytoplankton community ecological thresholds of which spring being higher than those in *** for individual species,Prorocentrum donghaiense and Noctiluca scintillans were identified as the most tolerant and sensitive indicator species in spring and summer,*** exhibited strong indications in response to environmental *** findings highlighted that phytoplankton community structure in this region was stable when environmental gradients were below the thresholds of sensitive species,whereas potential harmful algal blooms may occur when environmental gradients exceeded the thresholds of tolerant species.

关键词： ecological thresholds phytoplankton community environmental gradients indicator species coastal waters of northern Zhejiang Province

The biogeographical distribution of tree species-abundance and its relation to climatic factors in mass islands

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Acta Oceanologica Sinica 2017年第9期36卷 87-90页

作者： LI Xiaoming WU Chengzhen GU Wu YE Ran ZHANG Haibo QI Ping WANG Shengqiang ZHOU Siying WEI Yongjie cai yanhong State Oceanic Administration Beijing 100860 China Wuyi University Wuyishan 354300 China Marine Environmental Monitoring Center of Ningbo Ningbo 315012 China Marine Environmental Monitoring Center of Tianjin Tianjin 300450 China

Tree species-abundance in forests is a function of geographical area and climate, although it is not clear whether such relationships apply to mass islands. We examined the spatial pattern of tree species in mass islands along the coast of Zhejiang, East China Sea using the Preston model, to identify the relationships between tree communities and climatic conditions. The results show that：（1） the biogeographical distribution of tree species-abundance conformes to Preston＇s log-normal pattern, and is in accordance with the findings in both tropical rainforests and estuarine forests;（2） the climatic factors related to tree communities in mass islands are similar to that of the subtropical zone, including the major species of evergreen needle-leaf, broad-leaf and deciduous broad-leaf forests. We conclude that the Preston model can be applied to the trees of mass islands and thus facilitate the systematic ecological researches of vegetation species＇ composition in subtropical zone.

关键词： mass islands species-abundance spatial pattern log-normal model

剪切载荷作用下胶接材料界面动应力强度因子的研究

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机械强度 2008年第3期30卷 450-454页

作者：蔡艳红陈浩然大连理工大学工业装备结构分析国家重点实验室大连116024

主要研究剪切载荷作用下,胶接材料中弹性和粘弹性界面间Griffith裂纹尖端动态应力强度因子的时间响应。采用积分变换方法,得到Laplace域内弹性和粘弹性材料的应力和位移的含未知系数的表达式;引入位错密度函数,并通过边界条件和界面连... 详细信息

主要研究剪切载荷作用下,胶接材料中弹性和粘弹性界面间Griffith裂纹尖端动态应力强度因子的时间响应。采用积分变换方法,得到Laplace域内弹性和粘弹性材料的应力和位移的含未知系数的表达式;引入位错密度函数,并通过边界条件和界面连接条件,导出反映裂纹尖端奇异性的奇异积分方程组,采用Gauss积分,并运用Gauss-Jacobi求积公式化奇异积分方程组为代数方程组,利用配点法进行求解;最后经过Laplace逆变换,求得动态应力强度因子的时间响应。得到Ⅱ型动应力强度因子随着粘弹性材料的剪切松弛参量的增加而增大,膨胀松弛参量的增加而减小;随着弹性材料的剪切模量和泊松比的增加而增大。

关键词：胶接材料界面裂纹动态应力强度因子积分变换奇异积分方程

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竞争条件下的P2P网贷平台定价策略研究

清华大学学报（自然科学版） 2015年第4期55卷 470-474页

作者：张春霞蔡炎宏刘淳北京大学经济学院北京100871 中国农业银行北京100005 清华大学经济管理学院北京100084

互联网金融正在中国经济体制下迅猛发展,对整个金融生态产生积极影响,P2P网贷平台是其中最有活力和代表性的业务模式,而定价策略是其成功的核心要素。该文借鉴传统双边市场定价理论,建立竞争条件下P2P平台的定价模型,并就模型均衡状态... 详细信息

互联网金融正在中国经济体制下迅猛发展,对整个金融生态产生积极影响,P2P网贷平台是其中最有活力和代表性的业务模式,而定价策略是其成功的核心要素。该文借鉴传统双边市场定价理论,建立竞争条件下P2P平台的定价模型,并就模型均衡状态的经济意义进行探讨。建模分析结果表明:均衡状态下,平台对投资人的定价低于平台对借款人的定价;平台的利润与平台的差异化程度正相关;平台低于竞争对手定价时,将赢得更多的市场份额。相关理论结果可很好地解释现存P2P平台的不对称定价、产品差异化和价格战等实践。

关键词：互联网金融 P2P网贷平台双边市场定价策略

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无限长条板中弹性与粘弹性界面裂纹尖端场

复合材料学报 2005年第6期22卷 156-164页

作者：蔡艳红陈浩然王灿大连理工大学工业装备结构分析国家重点实验室大连116024

研究无限长条板中粘弹性-弹性界面Griffith裂纹在Ⅰ型突加载荷作用下,裂纹尖端动态应力强度因子的时间响应。利用积分变换方法、Fourier和Laplace变换,分别推导出了弹性和粘弹性问题的控制方程组;引入位错密度函数,并结合边界条件,导出... 详细信息

研究无限长条板中粘弹性-弹性界面Griffith裂纹在Ⅰ型突加载荷作用下,裂纹尖端动态应力强度因子的时间响应。利用积分变换方法、Fourier和Laplace变换,分别推导出了弹性和粘弹性问题的控制方程组;引入位错密度函数,并结合边界条件,导出了反映裂纹尖端奇异性的Cauchy型奇异积分方程组,运用Cheby-shev正交多项式化奇异积分方程组为代数方程组,用配点法进行求解;最后用Laplace积分变换数值反演方法,将拉氏域内的解反演到时间域内,求得动态应力强度因子的时间响应,并对材料参数的影响进行了分析。结果表明,剪切松弛参量对Ⅰ型动应力强度因子的影响小于对Ⅱ型的影响,而膨胀松弛参量对Ⅰ型动应力强度因子的影响大于对Ⅱ型的影响。

关键词：粘弹性界面裂纹动态应力强度因子位错密度函数奇异积分方程

Comparison of medium-term results of minimally invasive plating osteosynthesis and open reduction and internal fixation for mid-distal humeral shaft fractures

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Chinese Medical Journal 2022年第22期135卷 2764-2766页

作者： Bo Yin Lianhua Li Zheng Lu Jie Gao Huayong Zeng yanhong cai Yuanming He Zhi Liu Department of Orthopedic Surgery Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China Senior Department of Orthopedics the Fourth Medical Center of Chinese People's Liberation Army(PLA)General HospitalBeijing 100048China Medical Supplies Center of PLA General Hospital Beijing 100700China

To the Editor:There is controversy in the literature on the benefits of open reduction and internal fixation(ORIF)and minimally invasive plating osteosynthesis(MIPO)for mid-distal humeral shaft fractures.[1]ORIF has the advantages of anatomical reduction,strong fixation,and little impact on the function of the elbow and shoulder ***,it has some disadvantages,including the need for a large incision and more dissection of soft tissues,interrupting blood supply to the fracture site,resulting in difficulties in healing and an increased risk of bone non-union,and a high risk of iatrogenic radial nerve *** contrast,treatment of mid-distal humeral shaft fractures by MIPO has the advantages of less dissection of soft tissues,avoidance of exposure of the radial nerve,and a low risk of iatrogenic radial nerve *** study aimed to compare the medium-term safety and effectiveness of MIPO and conventional ORIF in the treatment of mid-distal humeral shaft fractures.

关键词： healing distal union

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蠕变材料Ⅰ型动态扩展裂纹尖端场

力学学报 2005年第5期37卷 573-578页

作者：唐立强蔡艳红哈尔滨工程大学建筑工程学院哈尔滨150001 大连理工大学工业装备结构分析国家重点实验室大连116024

为了研究黏性效应作用下的动态扩展裂纹尖端渐近场,建立了蠕变材料Ⅰ型动态扩展裂纹的力学模型.首先,依据在稳态蠕变阶段,弹性变形和黏性变形同时在裂纹尖端场中占主导地位,由量级协调可知,应力和应变具有相同的奇异量级,即(σ,ε)∝r-1... 详细信息

为了研究黏性效应作用下的动态扩展裂纹尖端渐近场,建立了蠕变材料Ⅰ型动态扩展裂纹的力学模型.首先,依据在稳态蠕变阶段,弹性变形和黏性变形同时在裂纹尖端场中占主导地位,由量级协调可知,应力和应变具有相同的奇异量级,即(σ,ε)∝r-1/(n-1),其次,通过渐近分析推导出动态扩展裂纹尖端场的控制方程并求得了裂纹尖端应力、应变和位移分离变量形式的渐近解.最后,采用双参数打靶法求得了裂纹尖端应力、应变的数值结果.数值计算表明,裂尖场主要受材料的蠕变指数n和马赫数M的控制;在Ⅰ型动态扩展裂纹前方,环向应变达到最大值,可据此建立断裂准则.由于裂纹稳定扩展与非稳定扩展的主奇异项相同,因此对于稳定扩展裂纹的渐近分析方法,同样适用于非稳定的裂纹扩展问题.

关键词：蠕变材料 Ⅰ型动态扩展裂纹尖端场