台风引起的海浪灾害对我国黄、渤海沿岸影响巨大,严重威胁相关区域人民群众生命财产安全。本文主要利用ERA5(the fifth generation European Center for Medium-Range Weather forecasts atmospheric reanalysis of the global climate...台风引起的海浪灾害对我国黄、渤海沿岸影响巨大,严重威胁相关区域人民群众生命财产安全。本文主要利用ERA5(the fifth generation European Center for Medium-Range Weather forecasts atmospheric reanalysis of the global climate)风场研究了两类不同移动路径下的台风(1909号台风“利奇马”和1109号台风“梅花”)在黄、渤海区域的海浪场的时空分布特征及风-浪成长关系。结果表明:两个台风引起的海浪的有效波高空间分布明显不同,波高的分布和风速对应,而海浪周期与风速、波高的分布无明显相关性,波向较风向偏于台风移动方向且两者偏差较大;两个台风进入黄海之前就形成一个从黄海向渤海的“涌浪舌”。海浪成分方面,台风“利奇马”引起的沿海区大浪主要是风浪,而台风“梅花”移动路径的右侧以风浪为主,左侧则主要是涌浪;通过建立无因次波高与无因次周期的幂律关系、以及有效波高关于风速的二次多项式变化关系,研究了风-浪成长特性,结果发现,台风浪的成长特性与台风过程关系不明显,但与所处水域的水深和海底地形地貌有关,表现为两个台风在黄海区域的台风浪成长较渤海区域更为充分。展开更多
目的·探讨入住重症监护病房(intensive care unit,ICU)救治的危重孕产妇的临床特征及死亡情况。方法·选择2007年1月—2018年12月于上海交通大学附属第一人民医院南院ICU救治的危重孕产妇283例。根据入住ICU的主要病因是否与...目的·探讨入住重症监护病房(intensive care unit,ICU)救治的危重孕产妇的临床特征及死亡情况。方法·选择2007年1月—2018年12月于上海交通大学附属第一人民医院南院ICU救治的危重孕产妇283例。根据入住ICU的主要病因是否与妊娠相关,将患者分为妊娠并发症组(175例)和妊娠合并症组(108例)。采用统计学方法比较病例资料的组间差异。结果·妊娠并发症组孕产妇入住ICU的前3位病因依次是妊娠期高血压疾病、产科出血及妊娠剧吐导致的代谢紊乱,妊娠合并症组的前3位病因依次是妊娠合并心脏疾病、妊娠合并感染及妊娠合并急性胰腺炎。与妊娠合并症组相比,妊娠并发症组孕产妇的平均年龄较大、经产妇及未规律产检者较多、急性生理学与慢性健康评分Ⅱ(Acute Physiology and Chronic Health EvaluationⅡ,APACHEⅡ)分值较高,且进行内科穿刺操作(胸腔穿刺术、腹腔穿刺术、腰椎穿刺术、骨髓穿刺术)者较少(均P<0.05)。结论·危重孕产妇入住ICU的病因较多,深入分析该类孕产妇的临床特征将有助于ICU医师更好地认识和管理产科急危重症。展开更多
In this paper, we present a simple spring-block model for ocean internal waves based on the self-organized criticality （SOC）. The oscillations of the water blocks in the model display power-law behavior with an expo...In this paper, we present a simple spring-block model for ocean internal waves based on the self-organized criticality （SOC）. The oscillations of the water blocks in the model display power-law behavior with an exponent of -2 in the frequency domain, which is similar to the current and sea water temperature spectra in the actual ocean and the universal Garrett and Munk deep ocean internal wave model [Geophysical Fluid Dynamics 2 （1972） 225; J. Geophys. Res. 80 （1975） 291]. The influence of the ratio of the driving force to the spring coefficient to SOC behaviors in the model is also discussed.展开更多
With the increasing construction of artificial beach in coastal areas, it is of practical significance to study the beach surface deformation of artificial beach profile. Previous studies only focus on a single wave d...With the increasing construction of artificial beach in coastal areas, it is of practical significance to study the beach surface deformation of artificial beach profile. Previous studies only focus on a single wave dynamic factor, and it is difficult to predict the beach deformation of artificial beach profile under the storm surge-wave co-action. To solve this problem, the cross-section physical model test method was used to study the beach surface deformation of a typical artificial beach profile in Shuangdao Bay, Weihai, Shandong Province, after continuous wave actions till they stabilize. The characteristics of beach surface deformation under the conditions of constant water levels, laddershaped water level combined with corresponding wave elements and storm surge-wave co-action are compared and analyzed. A beach profile model which satisfies the theory of Bruun model is proposed. The test results show that the maximum scour depth of beach under storm surge-wave co-action is smaller and the scour range is obviously larger than that under the condition of constant water levels or ladder-shaped water level. The evaluation of the maximum scour depth by traditional model test tends to be conservative while the evaluation of the scour range is insufficient.The research results can provide scientific reference for designing artificial beaches.展开更多
Storm surges are cataclysmic natural disasters that occur along the coasts and are usually accompanied by large waves.The effects of coupled storm surges and waves can pose a significant threat to coastal security.Pre...Storm surges are cataclysmic natural disasters that occur along the coasts and are usually accompanied by large waves.The effects of coupled storm surges and waves can pose a significant threat to coastal security.Previous labo-ratory studies on the effects of storm surges and waves on coastal structures have typically utilized steady water levels and constant wave elements.An indoor simulation of the coupled processes of tides and waves is developed by adding a tide generation system to an existing laboratory wave basin to model continuous dynamic tide levels so that tide generation and wave-making occur synchronously in the pool.Specific experimental methods are given,which are applied to further study waves overtopping on artificial sea dikes and coastal flooding evolution under the coupled actions of tides and waves.The results of the overtopping discharge obtained by the test with a dynamic water level are compared with those obtained from steady water level tests and the existing empirical formula.In addition,the impacts of ecological coastal shelterbelts and structures on coastal flood processes and distributions are also investi-gated.The proposed simulation methods provide a new approach for studying the effects of storm surges and waves on coastal areas.The study also aims to provide a reference for coastal protective engineering.展开更多
文摘台风引起的海浪灾害对我国黄、渤海沿岸影响巨大,严重威胁相关区域人民群众生命财产安全。本文主要利用ERA5(the fifth generation European Center for Medium-Range Weather forecasts atmospheric reanalysis of the global climate)风场研究了两类不同移动路径下的台风(1909号台风“利奇马”和1109号台风“梅花”)在黄、渤海区域的海浪场的时空分布特征及风-浪成长关系。结果表明:两个台风引起的海浪的有效波高空间分布明显不同,波高的分布和风速对应,而海浪周期与风速、波高的分布无明显相关性,波向较风向偏于台风移动方向且两者偏差较大;两个台风进入黄海之前就形成一个从黄海向渤海的“涌浪舌”。海浪成分方面,台风“利奇马”引起的沿海区大浪主要是风浪,而台风“梅花”移动路径的右侧以风浪为主,左侧则主要是涌浪;通过建立无因次波高与无因次周期的幂律关系、以及有效波高关于风速的二次多项式变化关系,研究了风-浪成长特性,结果发现,台风浪的成长特性与台风过程关系不明显,但与所处水域的水深和海底地形地貌有关,表现为两个台风在黄海区域的台风浪成长较渤海区域更为充分。
文摘目的·探讨入住重症监护病房(intensive care unit,ICU)救治的危重孕产妇的临床特征及死亡情况。方法·选择2007年1月—2018年12月于上海交通大学附属第一人民医院南院ICU救治的危重孕产妇283例。根据入住ICU的主要病因是否与妊娠相关,将患者分为妊娠并发症组(175例)和妊娠合并症组(108例)。采用统计学方法比较病例资料的组间差异。结果·妊娠并发症组孕产妇入住ICU的前3位病因依次是妊娠期高血压疾病、产科出血及妊娠剧吐导致的代谢紊乱,妊娠合并症组的前3位病因依次是妊娠合并心脏疾病、妊娠合并感染及妊娠合并急性胰腺炎。与妊娠合并症组相比,妊娠并发症组孕产妇的平均年龄较大、经产妇及未规律产检者较多、急性生理学与慢性健康评分Ⅱ(Acute Physiology and Chronic Health EvaluationⅡ,APACHEⅡ)分值较高,且进行内科穿刺操作(胸腔穿刺术、腹腔穿刺术、腰椎穿刺术、骨髓穿刺术)者较少(均P<0.05)。结论·危重孕产妇入住ICU的病因较多,深入分析该类孕产妇的临床特征将有助于ICU医师更好地认识和管理产科急危重症。
基金supported by the Key Project of National Natural Science Foundation of China under Grant No.40730842the Knowledge Innovation Program of the Chinese Academy of Sciences under Grant No.KZCX2-YW-201the Postdoctoral Special Fund for the Innovation Program of the Shandong Province
文摘In this paper, we present a simple spring-block model for ocean internal waves based on the self-organized criticality （SOC）. The oscillations of the water blocks in the model display power-law behavior with an exponent of -2 in the frequency domain, which is similar to the current and sea water temperature spectra in the actual ocean and the universal Garrett and Munk deep ocean internal wave model [Geophysical Fluid Dynamics 2 （1972） 225; J. Geophys. Res. 80 （1975） 291]. The influence of the ratio of the driving force to the spring coefficient to SOC behaviors in the model is also discussed.
基金financially supported by the NSFC-Shandong Joint Fund (Grant No. U1706216)the Major Project of Nanjing Hydraulic Research Institute Funds (Grand Nos. Y220002, Y220013 and Y221017)+1 种基金the Water Conservancy Science and Technology Project of Jiangsu Province(Grant No. 2019009)the Water Conservancy Planning Project of Jiangsu Province (Grant No. GHB-HT-202100)
文摘With the increasing construction of artificial beach in coastal areas, it is of practical significance to study the beach surface deformation of artificial beach profile. Previous studies only focus on a single wave dynamic factor, and it is difficult to predict the beach deformation of artificial beach profile under the storm surge-wave co-action. To solve this problem, the cross-section physical model test method was used to study the beach surface deformation of a typical artificial beach profile in Shuangdao Bay, Weihai, Shandong Province, after continuous wave actions till they stabilize. The characteristics of beach surface deformation under the conditions of constant water levels, laddershaped water level combined with corresponding wave elements and storm surge-wave co-action are compared and analyzed. A beach profile model which satisfies the theory of Bruun model is proposed. The test results show that the maximum scour depth of beach under storm surge-wave co-action is smaller and the scour range is obviously larger than that under the condition of constant water levels or ladder-shaped water level. The evaluation of the maximum scour depth by traditional model test tends to be conservative while the evaluation of the scour range is insufficient.The research results can provide scientific reference for designing artificial beaches.
基金This study was financially supported by the NSFC-Shandong Joint Fund Key Project(Grant No.U1706216)the Innovative Research Foundation of Ship General Performance(Grant No.31422118)the Nanjing Hydraulic Research Institute Special Fund for Basic Scientific Research of Central Public Research Institutes(Grant Nos.Y220013 and Y222004).
文摘Storm surges are cataclysmic natural disasters that occur along the coasts and are usually accompanied by large waves.The effects of coupled storm surges and waves can pose a significant threat to coastal security.Previous labo-ratory studies on the effects of storm surges and waves on coastal structures have typically utilized steady water levels and constant wave elements.An indoor simulation of the coupled processes of tides and waves is developed by adding a tide generation system to an existing laboratory wave basin to model continuous dynamic tide levels so that tide generation and wave-making occur synchronously in the pool.Specific experimental methods are given,which are applied to further study waves overtopping on artificial sea dikes and coastal flooding evolution under the coupled actions of tides and waves.The results of the overtopping discharge obtained by the test with a dynamic water level are compared with those obtained from steady water level tests and the existing empirical formula.In addition,the impacts of ecological coastal shelterbelts and structures on coastal flood processes and distributions are also investi-gated.The proposed simulation methods provide a new approach for studying the effects of storm surges and waves on coastal areas.The study also aims to provide a reference for coastal protective engineering.
