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31.
一种便携式船舶气象仪仿真仪 总被引:2,自引:0,他引:2
为了解决船舶气象仪维修过程中存在的故障诊断困难、对维修人员要求较高以及专家随船维修不现实等问题,研制了一种便携式船舶气象仪仿真仪。该仿真仪的硬件部分采用模块化设计,主要模块均设计有基于AVR单片机的低功耗嵌入式系统,各模块间通过CAN总线连接,并可按需组态;软件部分设计有基于专家知识库和故障树分析法的专家系统故障诊断模型。试验结果表明,该仿真仪能够对现有各型号船舶气象仪的故障进行快速识别和准确定位,从而大大提高了船舶气象仪的维修保障能力。 相似文献
32.
为了研究表面微结构与自抛光的协同防污效果,将具有吸水溶胀能力的微球加入到自抛光树脂中,通过交联反应制备了表面微结构自抛光防污涂层,考察了涂层浸水过程中表面微结构形貌、溶胀、自抛光性能和抑制小球藻附着性能。研究结果表明:涂层自抛光过程中,微结构形貌的变化随微球含量的增加而更加明显;涂层溶胀率与微球的含量正相关,自抛光率与可水解单体含量正相关,但可水解单体含量过大时,涂层溶胀与自抛光成相互制约关系;小球藻附着率随微球含量的增加而增大,随可水解单体含量的增加而下降,当微球分散液质量分数为10%、可水解单体质量分数为40%时,涂层抑制小球藻附着的效果最佳。 相似文献
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本研究采用湿法制粒、流化床制粒包衣、湿法制粒流化床包衣三种工艺分别制备海水仔稚鱼微粒饲料,并对饲料的性能进行分析比较。固体原料超微粉碎后粒径小于20 μm,然后与液体原料经充分混合后作为基础饲料。制备的饲料粒径大多为150~840 μm。扫描电镜观察结果:湿法制粒工艺制备的饲料表面没有连续均匀一致的表面结构;流化床制粒包衣工艺制备的饲料表面有光滑致密的包衣膜;湿法制粒流化床包衣工艺制备的饲料形状较规则,表面有连续均匀一致的包衣膜。湿法制粒、流化床制粒包衣、湿法制粒流化床包衣三种工艺制备的微粒饲料(250~420 μm)在3.50%NaCl溶液1 h的氮保留率分别为43.6%、52.3%、57.5%;沉降速率分别为5.1、4.5、4.9 mm/s;均能均匀的分散于整个水体。 相似文献
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37.
海洋环境下混凝土强度的经时变化模型 总被引:16,自引:0,他引:16
牛荻涛 《西安建筑科技大学学报(自然科学版)》1995,27(1):49-52
在总结分析国内外混凝土长期暴露试验和经年建筑物实测结果基础上,分析了海洋环境下混凝土强度的经时变化规律,提出了混凝土强度平均值和标准差的经时数学模型。 相似文献
38.
《Energy Policy》2016
Commercial fishermen are arguably the stakeholder group most likely to be directly impacted by the expansion of the marine renewable energy (MRE) sector. The potential opposition of fishermen may hinder the development of MRE projects and the provision of benefit schemes could to enhance acceptance. Benefit schemes refer to additional voluntary measures that are provided by a developer to local stakeholders. The aim of this study is to explore the issue of the provision of benefit packages to local fishing communities and financial compensation measures for fishermen who may be impacted by MRE projects. Semi-structured interviews were conducted with fourteen fishermen from three separate case study sites around the island of Ireland where MRE projects were being developed. In addition, ten company fisheries liaison officers (CFLOs) who have worked on MRE projects in the UK and Ireland were also interviewed. The interviews were analysed under the headings of local employment, benefits in kind, compensation and community funds and ownership of projects. Analysis shows that there is uncertainty among fishermen over whether they would benefit or gain employment from MRE. Provision of re-training schemes and preferential hiring practices could be used by MRE developers to reduce this uncertainty. There was also agreement between fishermen and CFLOs on the need for the provision of an evidence-base and a standard approach for the calculation of disruption payments. A formal structure for the provision of benefit schemes for fishermen would be useful. Furthermore, schemes that provide a range of benefits to fishermen and other stakeholders over the lifetime of a MRE project are more likely to be successful at enhancing acceptance. 相似文献
39.
《International Journal of Hydrogen Energy》2019,44(56):29743-29751
Operational rules and control strategies of the chemically recuperated gas turbine (CRGT) in the marine propulsion are investigated in this paper. The Minimization of Gibbs free energy method is used to calculate the diesel-steam reforming reaction which products synthetic hydrogen rich fuels, and a universal model of the chemical regenerator which is easily applied to different application environments is created. The hydrogen production and hydrogen molar fraction are investigated to verify that the CRGT improve the combustion performances under low working conditions. Off-design calculations are performed to derive proper operational rules, and transient calculations are performed to investigate the best control strategies for the systems. The modelling approach of the chemical regenerator can be generally used in the chemically recuperated gas turbine. The elaborate operational rules can greatly improve the thermal efficiencies under every working condition. The system using synchronous control strategies have better regulation speed and operation stability than that using asynchronous control strategies. 相似文献
40.
E. Altunsaray G. Neser C. Erbil K. T. Gürsel D. Ünsalan 《Materialwissenschaft und Werkstofftechnik》2012,43(12):1053-1058
This study is aimed to find the fatigue behavior of Glass Reinforced Plastics, a material which is a widely preferred material for small marine crafts, as well as several other applications. The type of composite tested is hand‐laid E‐glass non‐crimp reinforcements with an polyester resin matrix. The specimens were produced in two standard thicknesses and with these material directions and were tested both under atmospheric and simulated seawater environments for fatigue. It was seen that the results of fatigue lifetime obtained by testing the material in seawater is much lower than the results obtained from testing similar specimens under atmospheric conditions. However, the stress curves indicate the same slope, suggesting that the fatigue failure mechanism of both testing conditions is the same and the fiber‐related factors dominate. It was found that the thickness and material direction did not have a significant effect on the fatigue behavior of the material. 相似文献