超大型海洋浮式结构物开发过程需要解决的关键技术问题   总被引：15，自引：4，他引：11  

崔维成  吴有生 《海洋工程》2000,18(3):1-8

在我国研制和开发超大型海洋海式结构物（ＶＬＦＳ）对本世纪河北省工程的持续发展具有极为深远的战略意义。为了在我国研制和开发ＶＬＦＳ,首先必须要表楚在超大型海洋浮式结构物开发过程中需要解决的关键技术问题。本文通过对国际上大量文献的阅读和消化并经归纳和整理,从六个方面提出了需要研究解决的问题：（１）概念设计,（２）动力特性预报,（３）设计和建造,（４）可服役性、耐久性和可维性,（５）事故载荷和风险评估,  相似文献   

AffectRoute – considering people’s affective responses to environments for enhancing route-planning services     

Haosheng Huang  Silvia Klettner  Manuela Schmidt  Georg Gartner  Sven Leitinger  Andreas Wagner 《International journal of geographical information science》2014,28(12):2456-2473

Humans perceive and evaluate environments affectively. Some places are experienced as unsafe, while some others as attractive and interesting. These affective responses to environments influence people’s daily behavior and decision-making in space, e.g., choosing which route to take, or which place to visit. In this article, we report on a methodology of using people’s affective responses to environments for enhancing computer-based route planning. More specifically, we explore a crowdsourcing approach to model and collect people’s affective responses to environments; an Affect-Space-Model and a mobile application are developed to facilitate this crowdsourcing approach; a routing algorithm (named AffectRoute) is then proposed to aggregate and integrate the collected data for automatic route planning. Evaluation with human participants shows that the routes generated by considering people’s affective responses to environments are significantly preferred over the conventional shortest ones, which are employed in car navigation systems and many online route planners. In conclusion, considering people’s affective responses to environments contributes to the improvement of automatic route planning. The proposed method can be integrated into existing route-planning services (e.g., location-based services) to provide users with more satisfying routing results.  相似文献   

A Theoretical Explanation of Anomalous Atmospheric Circulation Associated with ENSO Modoki during Boreal Winter          下载免费PDF全文

XING Nan  LI Jian-Ping  LI Yao-Kun 《大气和海洋科学快报》2014,(4):352-357

Based on a linear model, the present study provides analytical solutions for ideal triple forcing sources similar to sea surface temperature anomaly （SSTA） pat- terns associated with El Nino-Southern Oscillation （ENSO） Modoki in winter. The ideal triple pattern is composed of an equatorially symmetric heat source in the middle and equatoriaUy asymmetric cold forcing in the southeast and northwest. The equatorially symmetric heat source excites low-level cyclonic circulation anomalies associated with Rossby waves in both hemispheres, while the northwest- ern and southeastern equatorially asymmetric cold sources induce low-level anomalous anticyclones associated with Rossby waves in the hemisphere where the forcing source is located. Low-level zonal winds converge toward the heat sources associated with Kelvin and Rossby waves. Due to unequal forcing intensity in the northwest and southeast, atmospheric responses around the equatorially symmetric forcing become asymmetric, and low-level cyclonic circulation anomalies in the Southern Hemisphere become greater than those in the Northern Hemisphere. Ascending （descending） flows coincide with heat （cold） sources, resulting in a double-cell structure over the regions of forcing sources. Ideal triple patterns similar to SSTA patterns associated with La Nina Modoki produce opposite atmospheric responses. The theoretical atmospheric responses are consistent with observed circulation anomalies associated with ENSO Modoki. Therefore, the theoretical solutions can explain the dynamics responsible for atmospheric circulation anomalies associated with ENSO Modoki events.  相似文献   

土体非线性参数变异性与地表响应的概率关系     

李波  孙锐  袁晓铭  陈红娟 《地震工程学报》2011,33(Z1)

场地土体非线性参数存在明显的变异性,因而与其相关的许多岩土工程问题都会受到其变异性的影响。采用数值模拟的方法研究了场地土非线性参数概率与场地地表加速度反应谱概率之间的关系。结果表明,场地土体动剪切模量比概率水平与场地地表加速度反应谱概率水平的关系随周期频段的变化而变化,粘性土在0.01 s～0.8 s周期内,无粘性土在0.02 s～0.7 s周期内,两者基本呈线性关系;场地土体阻尼比概率水平与地表加速度反应谱概率水平存在良好的对应关系,二者概率水平一致,且与反应谱的频段无关;在0.01 s～6.0 s周期频段内,无粘性土和粘性土的阻尼比概率与地表反应谱概率水平呈明显的线性关系。  相似文献   

一种新型波能发电装置的运动响应计算     

史宏达  刘栋  刘臻 《中国海洋大学学报(自然科学版)》2011,41(10):111-116

为分析碟形越浪式波能发电装置初步设计方案的合理性和不足,应用三维势流理论和波浪的辐射-衍射理论,结合水动力分析软件AQWA,计算在规则波浪作用下装置浮体6个自由度上运动的响应幅值算子(RAOs),考虑不规则波浪、风、流载荷的共同作用,对装置在工作海况和恶劣海况下的运动响应进行数值模拟分析,得到其时间历程结果。结果表明:装置结构外形设计合理,装置在其锚链张力腿锚泊系统定位下,运动响应满足工作稳定性要求和安全性要求。  相似文献   

A model simulating the processes in responses of glacier and runoff to climatic change   总被引：1，自引：0，他引：1  

Baisheng Ye  Kegong Chen 《中国地理科学(英文版)》1997,7(3):243-250

This paper presents a dynamic glacier model that simulates the processes in response of Glacier No. 1 in headwaters of the ürümqi River to various future climatic scenarios. The results indicate that the Glacier No. 1 will continue retreating if current climatic conditions prevail, until it reaches an equilibrium state of 1600 m in length after 700 to 800 years. If air temperature raise 1°C, the glacier would become a hanging glacier with a length of 300 m after 700 to 800 years. Due to its retreat, cooling function of the glacier would be weakened, resulting in the air temperature in glaciated area higher than that in ice-free areas. The results also indicate that the current glacier melt runoff is in higher value period in comparison with the runoff in the equilibrium state under the current climatic condition. If the air temperature continues increasing, however, the runoff would still increase to a new peak and then decrease rapidly. The project supported by the National Natural Science Foundation of China.  相似文献   

Automated suitable drainage network extraction from digital elevation models in Taiwan's upstream watersheds     

Wen‐Tzu Lin  Wen‐Chieh Chou  Chao‐Yuan Lin  Pi‐Hui Huang  Jing‐Shyan Tsai 《水文研究》2006,20(2):289-306

Automatically extracting drainage networks from digital elevation models coupled with the constant stream threshold value is a regular method. These extracted networks can be verified by comparing the channel initiation points with those from real networks. From the results analysed, the differences in channel initiation points will affect the network geometries, geomorphological indices and hydrological responses. This paper develops two automatic algorithms, the headwater‐tracing method and the fitness index, to trace the flow paths from headwaters to the outlet and to calculate the reasonable stream threshold. Instead of the method determined by trial and error or field survey, the accurate channel initiation points can be obtained from airborne photographs coupled with high‐resolution SPOT images for suitable drainage network extraction. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

Factors influencing hazard management by municipalities: The case of coastal communities     

《Global Environmental Change》2022

As climate and anthropogenic changes increase the vulnerability of coastal areas around the world, the threat (and reality) of coastal hazards grows. These threats arise particularly at a local level, calling out for more knowledge on how to best support coastal municipalities to deal with natural and human-induced hazards. This study seeks to add to the understanding through an examination of local-level experience with hazard planning and responses carried out by coastal municipalities, producing insights on how to reduce their vulnerability and support their resilience. It explores the factors influencing coastal municipalities’ management of relevant hazards to achieve comprehensive multi-hazard risk reduction and adaptation. We do so through a national survey of Canada’s coastal municipalities which assessed experience with hazards, risk perception, hazard prioritization, and the extent and specifics of hazard responses. We characterize the determinants of coastal municipalities’ behaviour and intervening factors, and conduct regression analyses to explain coastal municipalities’ risk perception, hazard prioritization, implementation of management processes for dealing with hazards, and the number of implemented or planned hazard responses. Six key factors were identified that influence hazard responses at the municipal level: experience with hazards; competing priorities; hazard visibility; access to resources (financial and technical capacity) and governance (institutional setting and political capacity). We conclude that municipal hazard responses can be reinforced by increasing the effectiveness of risk communication, promoting participatory processes, providing support for municipalities’ identified needs and priorities, ensuring municipalities have access to relevant information and expertise, and implementing integrated coastal governance and management.  相似文献   

Approximating peak responses in seismically isolated buildings using generalized modal analysis     

Tracy C. Becker  Stephen A. Mahin 《地震工程与结构动力学》2013,42(12):1807-1825

Although the ability to simulate accurately the detailed behavior of nonlinear isolation bearings and the effects of this nonlinearity on dynamic response of the isolated building is desirable, such detailed analyses are not feasible during initial design stages when bearing properties are being selected. However, it would be very beneficial to be able to estimate accurately key engineering demand parameters at the early stages of design to understand the dynamic response characteristics of the isolated structure and to balance and optimize the bearing and structural characteristics to achieve the performance goals set for the building. Unfortunately, classical modal response spectrum analysis methods do not provide accurate results for problems with large, nonclassical damping, as is characteristic of isolated buildings. To find a method capable of predicting peak building responses even with large nonclassical damping, generalized modal response spectrum analysis is implemented. The responses of several buildings having different heights and isolated by linear viscous as well as triple friction pendulum and single friction pendulum isolation systems are investigated. Generalized modal response spectrum analysis methods were found to give significantly better predictions for all systems compared with classical methods. The behavior of buildings isolated with single friction pendulum systems exhibiting sudden changes in stiffness could not be well predicted by either general or classical modal response spectrum analysis when effective damping was increased. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

基于生成对抗网络的建筑物损毁检测EI北大核心CSCD     

葛小三  陈曦  赵文智  李瑞祥 《测绘学报》2022,51(2):238-247

建筑物作为自然灾害中最受影响的承灾体之一,其损毁信息的准确提取对灾后应急救援具有十分重要的意义。本文借鉴多模态的思想,提出了一种自动检测损毁建筑物的recursive-generative adversarial networks(RS-GAN)方法,将损毁建筑物检测分为灾前建筑物识别和灾后损毁建筑物检测两个任务,且分别在两个GAN分支中完成。RS-GAN加入联合损失函数将两个GAN分支进行连接,充分利用两个任务之间的潜在互利性提升检测效果。RS-GAN利用第1条GAN分支识别建筑物灾前形状与位置,并将识别结果作为第2条GAN分支的输入进行损毁建筑物检测任务,从而使检测结果具有更清晰的轮廓。该方法为端到端模型,在不需要过多的人工干预情形下,实现了损毁建筑物的自动检测。为了验证RS-GAN模型的效果,在圣罗莎和密苏里两个数据集上进行了测试。试验结果表明,RS-GAN方法拥有更好的检测性能,在圣罗莎数据集上的总体精度和平均精度分别达到了0.90和0.86。  相似文献