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1.
ray tracing理论源于几何光学,将其引入海洋传输信道分析,在约当算法、帐篷定律等算法的支撑下,较好地解决了海洋环境与海洋信道的关系问题,为海上用频装备的合理使用提供了便利条件。  相似文献   

2.
船舶岸电系统研究综述   总被引:1,自引:0,他引:1  
随着海运业务的增加,船舶所带来的污染问题已引起社会的广泛关注。为了减小船舶对港口带来的污染,采用具有节能减排功能的船舶岸电技术作为供电方式,简要介绍了船舶岸电系统的一般组成,对线制匹配、相序检测、电压稳定、电力传输方式等关键技术进行了探讨,分析并提出某些问题的解决方法,同时分析了系统所涉及到的其它问题。  相似文献   

3.
自古以来,人类探索海洋,向往海洋与回归海洋的航海实践活动生生不息,从不间断。人类在这一伟大征程中所体现的不畏艰险,勇于探索的无数壮举与崇高精神永远值得思考与总结。人类在驾驭和征服海洋过程中所折射出的认知创新、技术创新与文化交融的创新硕果,将激励我们在可持续利用人类第二大生存空间———海洋与建设海洋强国的征程中,继续发扬伟大的郑和精神,不断创新航海技术,重铸我国航海事业的辉煌。  相似文献   

4.
S aint Martin Island is the only coral island and one of the well-known tourist spots in Bangladesh.Because of its geographic location,electricity cannot be supplied from the mainland through the electricity grid.Diesel generators and solar power are the only means of electricity generation presently available there.Surrounded by the sea,Saint Martin Island has the ideal conditions for wave energy extraction.In this research,numerical models have been developed using the Delft3 D simulation software to determine the wave characteristics of different locations around Saint Martin Island.The results have been calibrated and validated against the data obtained from well-known data sources.The wave power densities have been calculated using the data obtained from the simulation models.The findings of the research show that the wave power density increases significantly from shallow water to deep water and a large amount of wave energy can be extracted during the summer and rainy monsoon seasons.The maximum hourly average value of wave power in 2016 has been determined to be6.90 kW/m at location with a water depth of 27.80 m.Wave energy resources are also observed to be sufficiently stable with the coefficients of variation of wave power density less than 0.62,except for December,January,and May of that particular year.Moreover,the annual effective energies have been determined to be within the range of 36.57 to 57.28 MWh/m,which will be sufficient to meet the electricity requirement of the island communities.  相似文献   

5.
随着我国船舶行业的发展,船舶行业资源消耗大、污染物排放量大的问题日益明显,节能减排已经成为造船企业适应当前经济发展形势和提高未来竞争力必须要面对的重要课题。本文通过数据分析某造船企业动力车间各种能源供应分布中存在的不合理问题,认为动力车间供应的能源中电能的消耗在造船公司占用比重较大。对此,从起重设备的使用管理、电焊焊接设备的使用管理、车间空压站的管理、电力供应设备的管理等方面提出了管理建议。  相似文献   

6.
The air–sea CO2 exchange is primarily determined by the boundary-layer processes in the near-surface layer of the ocean since it is a water-side limited gas. As a consequence, the interfacial component of the CO2 transfer velocity can be linked to parameters of turbulence in the near-surface layer of the ocean. The development of remote sensing techniques provides a possibility to quantify the dissipation of the turbulent kinetic energy in the near-surface layer of the ocean and the air–sea CO2 transfer velocity on a global scale. In this work, the dissipation rate of the turbulent kinetic energy in the near-surface layer of the ocean and its patchiness has been linked to the air–sea CO2 transfer velocity with a boundary-layer type model. Field observations of upper ocean turbulence, laboratory studies, and the direct CO2 flux measurements are used to validate the model. The model is then forced with the TOPEX POSEIDON wind speed and significant wave height to demonstrate its applicability for estimating the distribution of the near-surface turbulence dissipation rate and gas transfer velocity for an extended (decadal) time period. A future version of this remote sensing algorithm will incorporate directional wind/wave data being available from QUIKSCAT, a now-cast wave model, and satellite heat fluxes. The inclusion of microwave imagery from the Special Sensor Microwave Imager (SSM/I) and the Synthetic Aperture Radar (SAR) will provide additional information on the fractional whitecap coverage and sea surface turbulence patchiness.  相似文献   

7.
随着各国越来越重视保护海洋环境,船舶垃圾的处理问题也越来越受到人们的关注。通过对水面舰艇固体垃圾的种类、数量和处理方法的介绍,并根据国内外船舶垃圾处理方面的一些法规要求,考虑到不同类型水面舰艇的特点,提出了相应的固体垃圾处理对策。  相似文献   

8.
美国海军海洋预报系统最早始于苏联时期,自此之后,美国海军制定了一系列计划,构建海洋观测网络,开发海洋数值模式,发展军事海洋学,旨在建成一套完整、精确的全球海洋预报系统并实现业务化应用。美国海军海洋学一直走在世界前沿,本文将对美国海军海洋预报系统的发展历程、成果及其现状进行阐述,这对于我国军事海洋学以及海洋预报系统的发展具有重要借鉴作用。  相似文献   

9.
This paper investigates wheather the actions of US ocean ports (since the passage of the Shipping Act of 1984) are supportive of the promotion of an efficient transportation system for US ocean commerce. In the short run, US ocean ports have generally been supportive of this efficiency goal;competiton among US ocean ports has has increased as is evident by the significant reduction that has occurred in port natural hinterlands. In the long run, port sunk costs, consolidations and cooperative activities, and long-term leases with ocean carriers are likely to be non-supportive of the efficiency goal.  相似文献   

10.
姚琦  王世明  张福曦 《船舶工程》2015,37(11):72-77
针对一种海洋波浪能轴流式叶轮波浪能发电装置,结合我国近海波浪特点,对该装置的叶轮进行结构设计、优化选型和实验验证。该海洋波浪能轴流式叶轮波浪能发电装置以水叶轮作为唯一的波浪能转化装置,能量转化效率是影响发电的重要因素。根据浮标的运动状态,结合我国近海水纹特征,得出不同设计参数下叶轮的轴向力、扭矩、相对出口压力、能量损失系数等关键数据。这些数据为制造样机提供力学及能量转化效率方面的指导作用。  相似文献   

11.
在全球化经济日趋一体化的今天,一旦货物链中的某个环节发生故障将产生连锁反应,导致多个国家地区以至全球经济的重创。海运由于其特殊性在当今货物链中扮演着极其重要的角色,而海运系统又是货物链中的脆弱环节,如何保证海运环节的通畅是保证整个货物链不断的关键。本着上述观点,探讨了Inmarsat新近推出的FteetF-77在保障海运通畅、保证全球货物链不断方面的重要应用,希望新技术业务的推出能对全球经济发展起一定的作用。  相似文献   

12.
王朋 《港口科技》2012,(4):26-29
为了提高工作效率,集装箱正面吊运机采用机电一体化行走机械伺服专用控制器。介绍整机电气控制系统的组成以及操纵系统、显示界面等。对产品应用结果进行分析。采用该装置大大简化操纵系统的操纵性,达到了预期效果。  相似文献   

13.
Wave energy from the ocean is currently a very popular renewable energy, and its development has primarily focused on the shape of the wave energy converter(WEC) used to efficiently convert wave energy into electrical energy. However, the free surface ocean wave problem is very complex and the parameters affecting WEC behavior are difficult to understand. In this paper, based on the Lattice-Boltzmann method, we present particle-based CFD simulation results for the pivoted-type WEC that exhibits both vertical and horizontal motions. In this method, the computation domain need not be a mesh and complex geometry is not a limiting factor. Using a free-surface turbulence model, we simulated the fluid-structure interaction. We detail our simulation results, which show good agreement with those in the literature.  相似文献   

14.
Ocean transportation has been mainly studied from an economic and strategic point of view. This paper adopts an operations management approach aiming at the identification of the value-adding attributes that characterize the ocean transportation industry. This is achieved by using Johansson et al.'s 1 four value metrics—service, quality, cost, time—which are used for the identification of the contribution that different factors make to the total created value. In this paper, multi-attribute utility theory (MAUT) has been used to measure and compare the value of different processes of various sectors of the ocean transportation industry. The application of MAUT methodology is illustrated with an example from the four sectors of the industry: liner, dry bulk, liquid bulk and specialized. Results suggest that there is strong emphasis placed by ocean transportation companies on quality and that there is differentiating importance put on service and cost by different sectors. Time is seen as the lowest value contributor by all four sectors of the surveyed companies.  相似文献   

15.
澳大利亚在建极地科考破冰船"努伊娜"号是一艘目前即将投用的国际极地海洋科学考察船。从船舶规范、船载科考能力、极地科考补给能力等3个方面,介绍这艘集海陆综合补给与南大洋科学考察于一身的新型极地科考破冰船,使读者了解当前世界极地科考船的设计、建造与考察功能等方面的最新发展态势。  相似文献   

16.
This United States stands alone amongst the nations of the world in its attempt to unilaterally regulate transnational ocean linear services. The major reason for current US regularity policies with regard to scheduled ocean transportation lies in its fundamental distruct of any form of co-operation amongst competitors as demonstrated by its history of antitrust legislation.

The linear industry, because of its unique technical and economic charectersitics has given rise to the establishment of ocean conferences—co ordinating sgreements between the operators of linear vessels. Whilst ocean conferences are permitted—even encouraged—by the their most diluted form, the so-called 'open conferences.

This Paper offers a critical review of Successive US regulatory practices in maritime transport. It is argued that these practices result in excess costs in US trades to the order of $1 billion annually, and that the linear industry's efficient functioning is seriously impaired by these rules-rules imposed by a government administration which fails to recognize that the linear industry's technical efficiency is of far greater importance than its market performance.  相似文献   

17.
This United States stands alone amongst the nations of the world in its attempt to unilaterally regulate transnational ocean linear services. The major reason for current US regularity policies with regard to scheduled ocean transportation lies in its fundamental distruct of any form of co-operation amongst competitors as demonstrated by its history of antitrust legislation.

The linear industry, because of its unique technical and economic charectersitics has given rise to the establishment of ocean conferences—co ordinating sgreements between the operators of linear vessels. Whilst ocean conferences are permitted—even encouraged—by the their most diluted form, the so-called ‘open conferences.

This Paper offers a critical review of Successive US regulatory practices in maritime transport. It is argued that these practices result in excess costs in US trades to the order of $1 billion annually, and that the linear industry‘s efficient functioning is seriously impaired by these rules-rules imposed by a government administration which fails to recognize that the linear industry‘s technical efficiency is of far greater importance than its market performance.  相似文献   

18.
液化天然气(LNG)作为一种公认的清洁能源,在船舶交通运输领域应用的市场前景十分广阔。同时,LNG也是一种高绝缘液体,在充装作业的过程中应尤为注意静电和杂散电流的危害,以防范引发LNG火灾等严重后果。通过分析静电和杂散电流产生及其造成危害的原理,提出并总结船舶LNG加注系统在防静电及杂散电流方面的应用建议。  相似文献   

19.
王世明  李淼淼  李泽宇  田卡 《船舶工程》2020,42(S1):130-135
潮流能是一种环保可再生的海洋新能源,随着世界各国重视潮流能的开发与利用,潮流能技术在国际上取得了不断突破。本文在简述国内外潮流能发电历程的基础上,重点介绍了近五年来国际潮流能技术现状及最新进展,对已建、在建的各种潮流能发电站的实验状况、实际并网发电应用情况进行了阐述,同时总结了各种潮流能水轮机的装机容量、累计发电量、额定功率等情况。通过国内外潮流能技术的应用分析,总结了目前潮流能开发利用存在的问题,并针对我国潮流能发展现状和趋势提出了几点建议。  相似文献   

20.
统计能量分析法及其损耗因子确定方法综述   总被引:7,自引:0,他引:7  
统计能量分析法(SEA)在中高频段被广泛用于预测复杂结构的振动和噪声传递,本文阐述了统计能量分析法及其在船舶上的应用和局限性。统计能量分析法将结构划分成若干子系统,这些子系统以在窄频带内存储的振动能量和模态数的多少为特征,耦合损耗因子和内损耗因子分别用来表示各子系统之间的耦合程度和能量的损失程度,是统计能量分析法应用中的重要参数,本文综述了近四十年来国内外统计能量分析法研究中确定损耗因子的方法。  相似文献   

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