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991.
本文简要分析了国外水翼艇附体的一些特征,重点介绍长江水翼客艇Ⅱ号(以下简称水翼Ⅱ号)附体的特点。由试验证实,将舵、水翼支柱和尾轴支架组合为一体,用一剖面代替三个不连续的剖面,可得到令人满意的阻力性能,满足附体阻力控制在总阻力的20%以内的设计要求。文中还介绍了水翼Ⅱ号三种附件组合体方案及模型阻力试验分析。 相似文献
992.
Labour/management practices in North American ports are undergoing fundamental changes in their shift from confrontation to Cooperation. Cooperation is increasing to counter competitive threats from other ports arising from intermodalism and transportation deregulation. Technological advances in port operations are reducing the number of longshore forces required and changing the skills required of those which remain. A recent survey of North American container terminals provided a 'snapshot' of current approaches of improving labour/management relations. Focusing on growth and development needs of individual port workers enhances morale and motivation resulting in environment. Many ports are introducing new management techniques including improved communications and training to enhance the motivation and productivity of their longshore forces. 相似文献
993.
The Haskind-Hanaoka relations for obtaining the wave-exciting forces, given the incoming and radiation potentials in floating rigid-body dynamics, are extended to deformable-body dynamics in the presence of a free surface and within the assumption of linear potentials theory. These relations are applied to the mode-superposition and the direct methods of solution of hydroelasticity problems. In other words, it is shown that regardless of the structural analysis method used in a hydroelasticity problem, the Haskind-Hanaoka relations can be used to calculate the wave-exciting forces without solving for the diffraction potential explicitly. These relations can also be used in the composite singularity distribution method to increase further the computational efficiency. 相似文献
994.
戴雅康 《大连铁道学院学报》1989,10(3):61-68
本文通过对用铌磷半钢配制的中磷闸瓦的金相组织、力学性能、物理性能和摩擦-磨损特性的研究及其实际运行,证明:其质量指标和使用性能完全满足 TB1159-76标准,并超过普通中磷闸瓦的技术水平;可使中磷铸铁闸瓦的原材料成本降低10%左右. 相似文献
995.
996.
本文用杆系结构动力有限元法分析了我国定型设计中具有斜桥门架的三座铁路简支桁架桥的空间自振特性,并在分析计算结果的基础上就自振频率的近似计算及用有限元法分析时计算模型的选取等问题作了讨论。 相似文献
997.
C. Szczepaniak A. Kesy Z. Kesy 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1991,20(5):283-295
In this work three first-order nonlinear, nonstationary differential equations describing a hydraulic torque converter in a power transmission system are used.
A linear model is obtained on the basis of these equations. This model is verified both theoretically and by an experimental test. On the basis of the calculations the torsional damping was determined. This permitted the damping performance of a power transmission system with a hydraulic torque converter to be defined and established. 相似文献
A linear model is obtained on the basis of these equations. This model is verified both theoretically and by an experimental test. On the basis of the calculations the torsional damping was determined. This permitted the damping performance of a power transmission system with a hydraulic torque converter to be defined and established. 相似文献
998.
999.
For the production development of marginal offshore oil fields or to achieve early production in offshore fields scheduled for full production facilities a jack-up drilling rig can be converted to operate as a mobile production unit. This paper presents a summary discussion of the main aspects to be considered in the design, conversion, installation and operation of a jack-up production unit. 相似文献
1000.
Providing effective training for managers in the maritime and ports sector in developing countries has proven to be a daunting task. Initial attempts by the United Nations Conference on Trade and Development (UNCTAD) in the 1970s led to the development of senior port manager residence courses in Sweden. However, Given the vast numbers of managers needing training a more eficient method was required. Using the systematic training techniques pioneered by the International Telecommunications Union, UNCTAD, in the 1980s initiated two parallel programme: Trainmer (Training development in Maritime Transport); and IPP (Improving Port Performance). Both of these programmes demonstrated considerable success in terms of the numbers of maritime and port managers receiving training opportunities. Increased cooperation amoungst international agencies providing training programmes should result in improved transport management training in the 1990s, lrading to increased efficiences in port and related transport systems. 相似文献