船舶修理中对焊接设备的检查要求

在造船和修船的过程中由于电焊机和被焊件之间的连接不当,造成了电流对船体的腐蚀,严重时可能造成船体穿孔。对腐蚀和穿孔的原因进行电路分析,指出几种不正确的连接方法,同时给出正确的连接方法。     

集装箱船计算机辅助排箱与配载研究

本文利用可视化窗口界面编程工具VisualBasic开发集装箱船设计程序，利用窗口、表格、图象、文件等工具来直观、快捷地帮助设计人员进行集装箱船的布置安排，并能结合线型绘制、容量和稳性计算程序进行重量、稳性、浮态的检验，做好排箱和配载的工作。程序设计体现了输入导向性、检查严密性，处理面向对象性和输出直观性。给出的一个实例说明了对程序的具体应用。     

大型油船（VLCC）系离海上单点（SPM）操纵的体会

操纵大型油船系离海上单点在中国引航史上还处于起步阶段，作者就首次参与大型油船系离海上单点浮筒的实践，总结了如何确保操纵安全的经验。     

Surf-riding and oscillations of a ship in quartering waves

The behavior of a ship encountering large regular waves from astern at low frequency is the object of investigation, with a parallel study of surf-riding and periodic motion paterns. First, the theoretical analysis of surf-riding is extended from purely following to quartering seas. Steady-state continuation is used to identify all possible surf-riding states for one wavelength. Examination of stability indicates the existence of stable and unstable states and predicts a new type of oscillatory surf-riding. Global analysis is also applied to determine the areas of state space which lead to surf-riding for a given ship and wave conditions. In the case of overtaking waves, the large rudder-yaw-surge oscillations of the vessel are examined, showing the mechanism and conditions responsible for loss of controllability at certain vessel headings.List of symbols c wave celerity (m/s) - C(p) roll damping moment (Ntm) - g acceleration of gravity (m/s²) - GM metacentric height (m) - H wave height (m) - I _x ,I _z roll and yaw ship moments of inertia (kg m²) - k wave number (m^–1) - K _H ,K _W ,K _R hull reaction, wave, rudder, and propeller - K _p forces in the roll direction (Ntm) - m ship mass (kg) - n propeller rate of rotation (rpm) - N _H ,N _W ,N _R hull reaction, wave, rudder, and propeller - N _P moments in the yaw direction (Ntm) - p roll angular velocity (rad/s) - r rate-of-turn (rad/s) - R(,x) restoring moment (Ntm) - Res(u) ship resistance (Nt) - t time (s) - u surge velocity (m/s) - U vessel speed (m/s) - v sway velocity (m/s) - W ship weight (Nt) - x longitudinal position of the ship measured from the wave system (m) - x _G ,z _G longitudinal and vertical center of gravity (m) - x _S longitudinal position of a ship section (S), in the ship-fixed system (m) - X _H ,X _W ,X _R hull reaction, wave, rudder, and propeller - X _P forces in the surge direction (Nt) - y transverse position of the ship, measured from the wave system (m) - Y _H ,Y _W ,Y _R hull reaction, wave, rudder, and propeller - Y _p forces in the sway direction (Nt) - z _Y vertical position of the point of action of the lateral reaction force during turn (m) - z _W vertical position of the point of action of the lateral wave force (m) Greek symbols angle of drift (rad) - rudder angle (rad) - wavelength (m) - position of the ship in the earth-fixed system (m) - water density (kg/m³) - angle of heel (rad) - heading angle (rad) - _e frequency of encounter (rad/s) Hydrodynamic coefficients K roll added mass - N _v ,N _r yaw acceleration coefficients - N _v N _r N _rr N _rrv ,N _vvr yaw velocity coefficients K. Spyrou: Ship behavior in quartering waves - X _u surge acceleration coefficient - X _u X _vr surge velocity coefficients - Y _v ,Y _r sway acceleration coefficients - Y _v ,Y _r ,Y _vv ,Y _rr ,Y _vr sway velocity coefficients European Union-nominated Fellow of the Science and Technology Agency of Japan, Visiting Researcher, National Research Institute of Fisheries Engineering of Japan     

Dynamics of ships running aground

A comprehensive dynamic model is presented for analysis of the transient loads and responses of the hull girder of ships running aground on relatively plane sand, gravel, or rock sea bottoms. Depending on the seabed soil characteristics and the geometry of the ship bow, the bow will plow into the seabed to some extent. The soil forces are determined by a mathematical model based on a theory for frictional soils in rupture and dynamic equilibrium of the fluid phase in the saturated soil. The hydrodynamic pressure forces acting on the decelerated ship hull are determined by taking into account the effect of shallow water. Hydrodynamic memory effects on the transient hull motions are modeled by application of an impulse response technique. The ship hull is modeled as an elastic beam to determine the structural response in the form of flexural and longitudinal stress waves caused by the transient ground reaction and hydrodynamic forces. A number of numerical analysis results are presented for a VLCC running aground. The results include bow trajectory in the seabed, time variation of the grounding force, and the maximum values of the sectional shear forces and bending moments in the hull girder.     

集装箱船弯扭耦合振动分析

本文基于薄壁结构力学基本理论，提出了一种适合于大开口集装箱船弯扭耦合振动分析的薄壁梁有限元模型。该模型考虑了翘曲、剪切及剖面转动的影响，以及货舱大开口和抗扭箱（甲板梁）引起的结构不连续性。其例中，计算结果与三维有限元分析结果、模型试验结果相当吻合，而薄壁梁有限元的计算效率要高得多，算例还表明抗扭箱（甲板梁）对提高集装箱船的抗扭刚度有十分重要的意义。     

远洋大型集装箱船动力装置选型论证

本文首先介绍了远洋大型集装箱船动力装置选型的变化趋势,就我国90年代将开发应用的3500 TEU 集装箱船主机选型,从船机桨匹配,燃油经济性,初投资,机舱布置,振动特性等多种因素综合比较分析优选得到最适宜的机型,此外,为提高3500 TEU 集装箱船的燃油经济性,对多种节能新技术进行了筛选.     

A theory of coupled beams for strength assessment of passenger ships

This paper describes a coupled beam method, which estimates elastic response in the longitudinal bending of a passenger ship with a large multi-deck superstructure. The method can be applied during an early project stage, when detailed three-dimensional finite element modelling is not yet possible. The theory is based on the assumption that each deck in the superstructure and also the main hull can be considered as a thin-walled beam. These beams are coupled to adjacent beams with springs modelling vertical and shear stiffness. The shear effect in the side and deck structures is included with options for large openings. As a result, the method allows for the calculation of the normal stresses and vertical deflections in the arbitrary location of the hull girder. Average longitudinal displacements of deck structures and shear stresses in the side structures can be estimated as well. Simplified structures were analysed in order to validate the coupled beam method against the three-dimensional finite element method.     

铁路运输中货车周转与货物运送时间的分析

对铁路货车周转时间及货物运送时间进行了较详细的探讨,对造成周转时间与货物运送时间延长的各时间因素及其影响程度进行了分析计算,并提出了相应的建议.     

内河智能交通系统研究

内河航运在运输成本、环保、可持续发展等方面优势突出,而内河航运管理相对滞后。提出内河智能交通系统的概念,阐明内河智能交通系统的3个关键技术:船舶定位、无线数据通信、电子河图显示与信息系统,并对我国发展内河智能交通系统提出建议。