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191.
大屏幕集装箱装卸桥仿真训练器研究与开发 总被引:1,自引:0,他引:1
汪诚强 《南通航运职业技术学院学报》2007,6(2):46-50
港口起重设备自2005年被国务院颁布的《特种设备安全监察条例》列为重点监察的特种设备以来,对其相关操作人员的培训越来越受到各港口作业单位的重视。为提高培训质量,降低培训成本,南通航运职业技术学院研发了大屏幕集装箱装卸桥仿真训练器。文章结合该仿真训练器的研发介绍了系统的基本组成、功能以及技术特点,并指出应用该模拟器的重要现实意义。 相似文献
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Grouted connections are intensively used in offshore rigs, platforms as well as jacket and monopile offshore wind turbine structures. Being located in remote offshore conditions, these connections can experience considerable adverse loading during their lifetimes. Degradation was reported inside similar connections, which were installed in the last three decades. Grouting in the offshore sites may often be proven difficult, which eventually leads to reduced load-bearing capacity of connections in the long run. Thus, repair and rehabilitation of such connections should be planned ahead to minimize operational delays and costs. In this study, scaled grouted connections were manufactured using a novel mould, whose integrity were monitored using digital image correlation (DIC). The connections were loaded under static load to visualize the main failure pattern using distributed fibre optic sensors and acoustic emission (AE) analysis. Grouted connections were then repaired using a cementitious injectable grout. The effectiveness of the grout injection was monitored using dye penetration technique. Finally, specimens are reloaded to identify the potential of such repair for grouted connections. 相似文献
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Stress evaluation of a submerged floating tunnel (SFT) is an issue important for determining the section dimensions required to resist environmental loads. However, the complex interaction between an SFT and surrounding fluid has confined most research on SFTs to longitudinal global time-history analyses based on Morison's equation [1]. Even though these analyses give sufficient information in the longitudinal direction, too little information about the circumferential direction compels an SFT section to be designed conservatively. This means that SFT design requires additional information on the structural behavior of the tunnel in the circumferential direction for efficient design. Accordingly, a supplementary approach by which to obtain structural responses in the circumferential direction is introduced in this paper. Upon consideration of the static responses equivalent to the dynamic behavior, three-dimensional (3-D) finite-element analyses of an SFT were performed by application of static loads corresponding to dynamic loads equivalent to those of wave, current and earthquake. The validation of each equivalent static load was supported by the results from comparison of the tension forces in mooring lines obtained using OrcaFlex [2] and ABAQUS [3]. These were used mainly for longitudinal dynamic analysis and 3-D stress evaluation, respectively, of an SFT. Based on the stresses obtained in the longitudinal and circumferential directions, the selection of suitable section dimensions for an SFT is considered. 相似文献
197.
Floating offshore wind turbines are a novel technology, which has reached, with the first wind farm in operation, an advanced state of development. The question of how floating wind systems can be optimized to operate smoothly in harsh wind and wave conditions is the subject of the present work. An integrated optimization was conducted, where the hull shape of a semi-submersible, as well as the wind turbine controller were varied with the goal of finding a cost-efficient design, which does not respond to wind and wave excitations, resulting in small structural fatigue and extreme loads.The optimum design was found to have a remarkably low tower-base fatigue load response and small rotor fore-aft amplitudes. Further investigations showed that the reason for the good dynamic behavior is a particularly favorable response to first-order wave loads: The floating wind turbine rotates in pitch-direction about a point close to the rotor hub and the rotor fore-aft motion is almost unaffected by the wave excitation. As a result, the power production and the blade loads are not influenced by the waves. A comparable effect was so far known for Tension Leg Platforms but not for semi-submersible wind turbines. The methodology builds on a low-order simulation model, coupled to a parametric panel code model, a detailed viscous drag model and an individually tuned blade pitch controller. The results are confirmed by the higher-fidelity model FAST. A new indicator to express the optimal behavior through a single design criterion has been developed. 相似文献
198.
针对PHP没有提供用户所要求的满足他们需要的特殊的功能,作者介绍了3种方法将由用户自由编制的函数加入PHP中,大大增强了PHP的功能。 相似文献
199.
电动机架悬新型驱动装置的基本结构与分析比较 总被引:4,自引:1,他引:3
着重介绍了4种具有盘形制动功能的轮对空心轴式电机架悬新型驱动装置的基本结构,并对它们的特点进行了全面的分析比较。结合我国常用速度200km/h机车的发展,提出了应积极开发研究掌握具有交流电动机、承载式传动齿轮箱、盘形制动功能、弹性架悬等特征的我国第二代电动机架悬技术。 相似文献
200.
吕佰铨 《减速顶与调速技术》2005,(3):5-7
文章介绍了发展重载运输以后对编组站作业带来的各种影响,并提出应对既有的调速设备和作业方式进行改造和改进来适应这一新变化. 相似文献