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完善维修体制提高舰船维修水平 总被引:1,自引:0,他引:1
随着装备的现代化、自动化和信息化,以装备使用时间确定维修间隔期的定期维修制度已不能满足舰船维修发展的需要,维修体制从以定期维修为主辅以视情维修的方式,逐步发展到以视情维修为主的预防性维修。必须彻底转变传统的维修观念,加强装备的视情设计,制订维修大纲,不断完善监测手段,建立和健全基地和舰员两级监测体系,进一步提高状态监测和故障诊断能力,将定期维修与视情维修结合起来,全面提高舰船装备的维修水平。 相似文献
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为节省维修费用,确保设备处于良好状态,我公司近几年对设备的维修模式进行了大刀阔斧的改革,从定额维修到社会化承包维修,再到专业化的服务总包。维修模式的变革带来了设备完好率的上升及维修成本的下降,为社会化、专业化维修探索出了一套行之有效的办法。1沃尔沃装载机维修模式的变化沃尔沃装载机是2005年9月引进到我公司的,当时维修模式以自主维修为主、外修为辅。 相似文献
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《舰船科学技术》2019,(20)
舰船维修成本估计直接影响舰船企业的运营效益,针对当前舰船维修成本估计方法存在的一些局限性,以延长舰船寿命,提出基于BP神经网络的舰船维修成本估计方法。首先介绍当前舰船维修成本估计研究现状,找到当前各种舰船维修成本估计方法的不足,然后在此基础上依据舰船维修成本变化特点,引入BP神经网络建立舰船维修成本估计模型,最后通过Matalab2017平台实现了舰船维修成本估计仿真实验。相对当前其他的舰船维修成本估计方法,BP神经网络可以更好地跟踪舰船维修成本变化特点,不仅舰船维修成本估计精度高,而且舰船维修成本估计建模时间短,为解决复杂多变的舰船维修成本估计问题提供了一种新的方法。 相似文献
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论述美国航母全寿命使用维修周期的组成、维修计划的模式、维修计划制订的原则和方法。在此基础上,分析不同维修模式对维修费用和效果带来的影响,进而提出提高维修效率、减少维修费用的途径和方法。 相似文献
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涡激振动响应预报对于深水海洋结构物的设计是非常重要的。近年来,基于圆柱体的受迫振荡实验数据提出了若干经验模型。针对潘志远提出的一种基于实验数据并且与立管的有限元模态分析有机结合的VIV预报模型,采用近期的一个阶梯状分布来流下的涡激振动响应实验测量数据,验证了该模型的有效性和局限性。 相似文献
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Wen -Jeng Hsueh 《Journal of Marine Science and Technology》1998,3(1):50-60
A semiactive-type absorber for vibration reduction of main hull girders was investigated. The semiactive absorber system includes a moving mass, support springs, dynamic dampers, and a control system. Only a small electrical power supply is needed for control of the damper valve and the operation of the control system. In this paper, the dynamics of the ship's hull and the constraints of the semiactive absorber are described first. Then, a suboptimal operation law is derived based on the properties of the absorber and the theory of optimal vibration reduction. The numerical simulation results show that the semiactive absorber is more efficient in hull vibration reduction than the passive absorber during critical periodical excitation from the propeller. The vibration caused by multifrequency excitation can also be suppressed by the semiactive absorber. In terms of effectiveness, the semiactive absorber is almost as effective as the active absorber. In particular, the performance of the semiactive absorber is excellent in the reduction of high-frequency fluctuations.List of symbols
C
h
(i)
damping matrices of the segmenti
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C
sb
structural damping coefficient of bending
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C
ss
structural damping coefficient of shear
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C
v
hydrodynamic damping coefficient
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EI
flexural rigidity
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f
a
force generated by the absorber
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f
ad
damper force of the semiactive absorber
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f
ext
total excitation force
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F
ext
(i)
generalized load vector in segmenti
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teÎ
the identity matrix
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J
performance index
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J
r
rotatory moment of inertia
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k
a
stiffness coefficient of the absorber
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K
h
(i)
stiffnes matrices of the segmenti
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K
s
A
s
G
s
shear rigidity
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k
v
hydrodynamic spring coefficient
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l
k
length of the segmentk
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m
a
mass of the absorber
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M
ext
total exciting moment
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M
h
(i)
mass matrices of the segmenti
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m
v
mass moment of inertia
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w
h
deflection of the center line of the hull
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W
h
(i)
vertical translation and shear slope of nodes in segmenti
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¯ w
d
displacement of the absorber mass relative to the hull
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¯ w
a
absolute displacement of the absorber mass
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¯ w (a, t)
absolute upward displacement of the hull atx=a
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slope deflection due to bending
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slope deflection due to shear
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Dirac delta function
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k
(i)
Kronecker delta function
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k
distribution function
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shape function vector 相似文献
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