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1.
宜昌长江公路大桥钢桥面铺装大修采用了由国内自主创新的ERS铺装技术。本文通过宜昌大桥的ERS铺装实践对ERS技术的原理和特点以及施工中必要的注意事项等进行了总结和归纳。  相似文献   

2.
张晓 《中国海事》2008,(2):44-47
中国交通部最近发出通知,要求中国国际航行的客船、客滚船、5,000载重吨及以上的液货船、船长90米及以上的散货船、船长150米及以上的普通货船应在2009年7月1日前满足ERS要求。文中介绍了ERS(船舶应急响应服务)产生的背景、实施的法律依据,并对ERS的概念以及如何加入和使用ERS作了较为详细的介绍。  相似文献   

3.
ERS能及时针对海损事故做出应急响应,协助船舶脱离危险,从而减小海损事故对生命、财产和海洋环境所带来的破坏。文章介绍了ERS的背景、服务特点、服务内容和服务周期及其应急流程,并对一般海损事故处理的关键技术要点进行了阐述。  相似文献   

4.
ERS利用快速计算方法和先进的三维建模技术,当船只在运营中发生意外时,能够快速有效的提供技术评估,协助遇险船舶脱离危险,从而减少事故对生命、财产、环境的破坏。介绍ERS的产生背景、服务方式和内容、以及应用前景展望。  相似文献   

5.
潘海涛 《水运工程》2004,(10):50-53
介绍国内外港口油气码头装载臂紧急脱离装置(ERS)的技术发展,论述该项技术在港口工程的应用和发展前景。  相似文献   

6.
6月14日上午9时50分,北京,中国船级社(CCS)总部ERS(船舶应急响应服务系统)指挥中心突然接到一个船东的紧急呼救--"中国船级社ERS指挥中心,我是大连航运集团有限公司"银河王子"轮,我们在渤海湾海域航行过程中汽车舱发生火灾,船舶已启动压力水雾施救,在施救过程中,由于下水管路堵塞不能及时排出,造成汽车大量消防积水,导致船舶横倾,请求提供事故后船舶稳性计算,以及脱险方案的相关建议.船上在组织救火,请启动船舶应急响应服务.船舶具体状态将随后报告."  相似文献   

7.
曹健 《中国船检》2013,(10):92-94
一艘船舶,一旦处于紧急状态,且该船舶的船东和船级社预先签订了船舶应急响应服务(ERS)协议,已建立稳性与结构强度有关的应急响应数据库,那么,船级社常设的岸基应急响应机构就会迅速集结,启动船舶应急响应数据库,按船东提出的要求提供包括破损稳性、破损强度、溢油等的计算分析,为协助船舶脱离危险提供技术支持,为船长/船东最终决策提供参考意见。  相似文献   

8.
针对LNG船、FSRU、岸基码头三者之间的通信没有统一控制的问题,基于控制中心的思想确定船岸及船船连接系统架构;依据SIGTTO规范对于光纤连接和电气连接通道的设定,对现有闲置端口进行新的功能定义,使得系统能够同时进行语音、系泊数据、含LNG的ESD,以及含CNG的ESD通信传输;采用双电气连接设计,保证能够兼容更广的码头类型;并制定ESD和ERS的操作程序,保障作业安全,设计方案符合规范、行业标准及安全作业要求,能够为FSRU的三方联动作业通信提供设计指导。  相似文献   

9.
开展舰船模块式设计研究的设想与建议   总被引:2,自引:0,他引:2  
本文提出了在我国开展舰船模块式设计技术研究的设想。文章论述了开展研究的必要性,并根据我国舰船装备的现状提出了开展研究的大致内容和重点,以及设想的研究途径和步骤。  相似文献   

10.
介绍了山东省港口企业开展科技创新活动的基本情况,并对开展创新活动的思路和科技发展的对策,作了详尽的叙述。  相似文献   

11.
This study investigates the effectiveness of the Singular Evolutive Extended Kalman filter (SEEK) and its variants (SEIK and SFEK filters) for data assimilation into a Princeton Ocean Model (POM) of the Mediterranean Sea. The SEEK filters are sub-optimal Kalman filters based on the approximation of the filter's error covariance matrices by singular low-rank matrices, reducing in this way extensive computational burden. At the initialization, the filters error covariance matrix is parameterized by a set of multivariate empirical orthogonal functions (EOFs) which describe the dominant modes of the system's variability. The Mediterranean model is implemented on a 1/4° × 1/4° horizontal grid with 25 sigma levels and is forced with 6-hour ECMWF re-analysis atmospheric data. Several twin experiments, in which pseudo-observations of altimetric data and/or data profiles were assimilated, were first performed to evaluate the filters performances and to study their sensitivities to different parameters and setups. The results of these experiments were very encouraging and helped in setting up an effective configuration for the assimilation of real data in near-real time situation. In the hindcast experiments, Topex/Poseidon and ERS weekly sea level anomaly data were first assimilated during 1993 and the filters solution was evaluated against independent Reynolds sea surface temperature (SST) analysis. The assimilation system was able to significantly enhance the consistency between the model and the assimilated data, although the improvement with respect to independent SST data was significantly less pronounced. The model SST was only improved after including SST data in the assimilation system.  相似文献   

12.
A sequential assimilative system has been implemented into a coupled physical–biogeochemical model (CPBM) of the North Atlantic basin at eddy-permitting resolution (1/4°), with the long-term goal of estimating the basin scale patterns of the oceanic primary production and their seasonal variability. The assimilation system, which is based on the SEEK filter [Brasseur, P., Verron, J., 2006. The SEEK filter method for data assimilation in oceanography: a synthesis. Ocean Dynamics. doi: 10.1007/s10236-006-0080-3], has been adapted to this CPBM in order to control the physical and biogeochemical components of the coupled model separately or in combination. The assimilated data are the satellite Topex/Poseidon and ERS altimetric data, the AVHRR Sea Surface Temperature observations, and the Levitus climatology for salinity, temperature and nitrate.In the present study, different assimilation experiments are conducted to assess the relative usefulness of the assimilated data to improve the representation of the primary production by the CPBM. Consistently with the results obtained by Berline et al. [Berline, L., Brankart, J-M., Brasseur, P., Ourmières, Y., Verron, J., 2007. Improving the physics of a coupled physical–biogeochemical model of the North Atlantic through data assimilation: impact on the ecosystem. J. Mar. Syst. 64 (1–4), 153–172] with a comparable assimilative model, it is shown that the assimilation of physical data alone can improve the representation of the mixed layer depth, but the impact on the ecosystem is rather weak. In some situations, the physical data assimilation can even worsen the ecosystem response for areas where the prior nutrient distribution is significantly incorrect. However, these experiments also show that the combined assimilation of physical and nutrient data has a positive impact on the phytoplankton patterns by comparison with SeaWiFS ocean colour data, demonstrating the good complementarity between SST, altimetry and in situ nutrient data. These results suggest that more intensive in situ measurements of biogeochemical nutrients are urgently needed at basin scale to initiate a permanent monitoring of oceanic ecosystems.  相似文献   

13.
To distinguish offshore and onshore seismic ground motions, conventional analyses in terms of peak ground acceleration (PGA) and earthquake response spectrum (ERS) have been carried out in a recent work by authors and other papers in literature. In the present study, distinct temporal and spectral characteristics between onshore and offshore earthquake ground motions are further investigated in time-domain and frequency-domain. The data used is 69 pairs of concurrent onshore and offshore ground motions collected from the Kyoshin Network (K-NET). Each pair of data are of approximately identical epicenter distances. Comparisons are made on zero-up-crossing period (Tz), peak-to-trough acceleration range (Apt) and period (Tpt), duration of ground motion (Td), predominant frequency (fp) and the spectral bandwidth parameter (ε). The results indicate that for offshore horizontal and vertical seismic signals, statistics of Tz, Tpt, Td and predominant period Tp tend to be larger than the onshore counterparts. Meanwhile, ε of the offshore vertical ground motions is also greater. Through the proposed energy ratio (ER) analysis, the spectral energy of offshore ground motion is found to shift to moderate and low frequency bands. The time-frequency analysis conducted by Hilbert-Huang transform (HHT) shows that the Hilbert spectra of offshore accelerations contain larger spectral energy than the onshore counterpart but the corresponding instantaneous frequencies at peak energy are smaller, especially for horizontal recordings. Therefore, larger dynamic response of offshore structures is prone to be induced by the offshore ground excitation. This is further validated through the dynamic analysis of a marine pipeline in case study.  相似文献   

14.
This paper presents Prototype Système 2 Global (PSY2G), the first Mercator global Ocean General Circulation Model (OGCM) to assimilate along-track sea level anomaly (SLA) satellite data. Based on a coarse resolution ocean model, this system was developed mainly for climatic purposes and will provide, for example, initial oceanic states for coupled ocean-atmosphere seasonal predictions. It has been operational since 3 September 2003 and produces an analysis and a two-week forecast for the global ocean every week. The PSY2G system uses an incremental assimilation scheme based on the Cooper and Haines [Cooper, M., Haines, K., 1996. Data assimilation with water property conservation. J. Geophys. Res., 101, 1059-1077.] lifting–lowering of isopycnals. The SLA increment is obtained using an optimal interpolation method then the correction is partitioned into baroclinic and barotropic contributions. The baroclinic ocean state correction consists of temperature, salinity and geostrophic velocity increments and the barotropic correction is a barotropic velocity increment. A reanalysis (1993–2003) was carried out that enabled the PSY2G system to perform its first operational cycle. All available SLA data sets (TOPEX/Poséïdon, ERS2, Geosat-Follow-On, Jason1 and Envisat) were assimilated for the 1993–2003 period. The major objective of this study is to assess the reanalysis from both an assimilation and a thermodynamic point of view in order to evaluate its realism, especially in the tropical band which is a key region for climatic studies. Although the system is also able to deliver forecasts, we have mainly focused on analysis. These results are useful because they give an a priori estimation of the qualities and capabilities of the operational ocean analysis system that has been implemented. In particular, the reanalysis identifies some regional biases in sea level variability such as near the Antarctic Circumpolar Current, in the eastern Equatorial Pacific and in the Norwegian Sea (generally less than 1 cm) with a small seasonal cycle. This is attributed to changes in mean circulation and vertical stratification caused by the assimilation methodology. But the model's low resolution, inaccurate physical parameterisations (especially for ocean–ice interactions) and surface atmospheric forcing also contribute to the occurrence of the SLA biases. A detailed analysis of the thermohaline structure of the ocean reveals that the isopycnal lifting–lowering tends to diffuse vertically the main thermocline. The impact on temperature is that the surface layer (0–200 m) becomes cooler whereas in deeper waters (from 500 to 1500 m), the ocean becomes slightly warmer. This is particularly true in the tropics, between 30°N and 30°S. However it can be demonstrated that the assimilation improves the variability in both surface currents and sub-surface temperature in the Equatorial Pacific Ocean.  相似文献   

15.
随着罗津港使用权的获取,自罗津港出入的中国船舶将不断增多,因此对日本海西部的气象保障服务需求势必不断增加。为加强日本海西部海事气象保障服务水平,使其能够为罗津港附近海域在海运、港口管理和海上作业等方面更好地起到规避风险、提高效益的作用,文中根据对目前日本海西部海事气象保障服务现状的调研结果,指出了当前日本海西部海事气象保障服务存在着区域划分不合理、精细化程度不足以及服务形式过于单一等问题。据此,结合目前国内外海事气象保障服务的思路,提出了针对于日本海西部的海事气象保障服务的建议,可为提升日本海西部海事气象保障服务的升级换代提供一些参考思路。  相似文献   

16.
This paper provides an up-to-date review of the previous literature concerning the impact of passenger rail franchising on productivity and costs in Britain, and also presents important new evidence. In particular, the extension in time of previously-used datasets offers the first opportunity to study the impacts of re-franchising. The previous literature emphasised the failure of franchising to produce sustained productivity gains, with a sharp deterioration in productivity after 2000. The new evidence presented offers a somewhat more positive view of the British experience. It suggests that part of what was previously considered to be falling productivity may in fact be due to exogenous changes in diesel prices. Further, new data suggests that the recent increases in costs have resulted in higher quality of service. Finally, competitive re-franchising, and the associated unwinding of short-term management and re-negotiated contracts, seems to have led to improvements in productivity between 2006 and 2008. Nevertheless, it remains the case that passenger rail franchising in Britain has failed to reduce costs in the way experienced in many other industries and in rail in other European countries. The evidence is that somewhat larger franchises, avoiding overlapping and optimising train density and length, should reduce costs. We also speculate that the major increase in wages and conditions of staff might be moderated by longer franchises, although that remains to be proved. This re-appraisal of the British case is important in the context of the wider international interest in the use of franchising in passenger rail, and its relevance to the current review of ways of introducing competition into the domestic rail passenger market in Europe.  相似文献   

17.
近年来,随着与船舶自主航行相关的信息技术、人工智能技术水平的提高,无人船舶行业取得了长足的发展,其在海上安保、环境监测等领域应用也越来越成熟。为推动无人船在海事管理方面的应用研究,破解港口水域海事监管手段不足的瓶颈问题,文中在分析港口水域海事监管特点和无人船系统建设条件的基础上,定量研究了无人船在港口水域海事监管应用面临的性能指标确定、船型平台选择、载荷设备搭配、运行管理体系建设等方面的具体问题,提出了一种港口水域海事监管无人船系统的应用解决方案。  相似文献   

18.
针对宁波舟山港岛屿岸线利用开发所遇到的问题,总结宁波舟山港选址和建设码头的经验,对宁波舟山地区港口建设码头选址过程中遇到的各类岛屿岸线问题进行分析,提出采用顺流连岛、炸礁清障、导流堤整治水流、避开转流回流段等整治措施,得出宁波舟山港地区码头选址可采用的有效整治利用岸线的方法。认为:宁波舟山港岛屿岸线整治和利用须使得该段岸线前的往复潮流主轴线基本顺直,避免转流和回流岸段。  相似文献   

19.
闫勇  韩鸿胜 《水道港口》2012,33(2):113-118
利用珠江口伶仃洋海域实测水文、泥沙及水深测量等现场实测资料分析,建立了南起万山群岛、北至虎门、东起汲水门、西至珠海—澳门的港珠澳大桥整体物理模型,研究工程实施对伶仃洋诸港口、伶仃航道、铜鼓航道及附近海域流场、潮位和水深变化的影响。结果表明:港珠澳大桥实施对潮流、潮位的影响仅在桥轴线上下游各4 km的范围内,对伶仃航道、铜鼓航道通航基本没有影响。  相似文献   

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