Due to the importance of the Arctic shipping route, the study investigates the interaction between side-by-side barges floating near an ice sheet, where the ice sheet is modeled as a semi-infinite elastic thin plate. The entire fluid flow field is described using two-dimensional linear velocity potential theory, and a hybrid method is employed to solve the disturbed velocity potential. Based on this approach, the boundary equations around the side-by-side barges are formulated, and the eigenfunction series of the velocity potential are expanded within the ice-covered domain. Similarly, the eigenfunction series in the far field are employed to satisfy the radiation condition. The boundary integral equations and the coefficients of the eigenfunction expansions are solved simultaneously, ensuring continuity of pressure and velocity at the interfaces between sub-domains. The study provides extensive results on the hydrodynamic forces acting on the barges and explores the effects of ice sheet and barge properties in detail.

Negative pressure adsorption can make use of deep-sea environmental pressure to provide a great adsorption force and it is a suitable fixed method for deep-sea applications. However, the deep-sea environment puts forward higher requirements for the sealing performance of negative pressure suction cups, so a more adaptable suction cup sealing device is needed. In this paper, a deep-sea adsorption device with rigid suction cups is designed, and the suction cup is sealed by O-ring. The influence of both section diameter and inner diameter of the O-ring on its preload, suction force, and extrusion failure is tested and analyzed. Moreover, the fitting formula is given to guide the selection of the section diameter and inner diameter of the O-ring. Furthermore, according to the summary of the experimental phenomenon, dual-accumulators configuration with stage pressures method is created, and the theoretical basis that the suction cup can achieve a larger suction force under the condition of a small preload force is given, which can provide a reference for the design of deep-sea adsorption devices and sealing structure.

Knuckle boom crane (KBC) mounted on a polar ship (PS) is a maritime engineering equipment widely used in offshore activities. The working performance of a PS-mounted KBC (PSKBC) may degrade quickly if manipulated manually under extreme working conditions in polar region. To address the challenges, a performance-maximum optimization method through trajectory planning is developed to further promote the intelligently unmanned lifting processes of the PSKBC. Firstly, the dynamic model of lifting activities of the PSKBC is established using Lagrangian equation, based on which the point-to-point trajectory planning (PTP) method is developed for lifting processes. Subsequently, the PTP‐based optimization model is established to realize the minimum energy consumption and time cost of the lifting activities of the PSKBC, and the obtained optimal lifting performance is compared with the traditional S-curve method. To verify the superiority of the proposed performance-maximum optimization method, numerical simulations of the lifting activities of the PSKBC with respect to different crane loads and final lifting positions are performed. Results indicate that the PTP‐based performance-maximum optimization method for the PSKBC can perfectly achieve better performances with applicable lifting trajectories regarding various working conditions and demands.

研究生学术道德和科研诚信是提升我国科研队伍人才综合素质的关键所在,同时也是创新型人才和科技强国的根本保障.面对研究生学术道德素养和科研诚信的现状和问题,需要充分发挥思想政治教育的核心引导作用,提升学生们遵守学术规范的要领,最大限度地摒弃和减少学术不端行为.对此,本文从研究生学术道德与诚信现状、研究生学术道德与诚信教育现状以及改善研究生学术思想道德教育途径等方面展开相应的探讨,为横向的教学实践提供参考.

针对目前润滑状态测试装置的局限性,提出一种双点接触自适应摩擦试验装置.该装置结合了摩擦因数法与接触电阻法的优点,在相对静止的双下试件上测量电阻,简化了电路的设计;利用浮动支撑机构实现加载力的平衡自动调节功能,采用自下而上的加载方式,降低了导轨与滑块之间的摩擦以及装置自重对测量的影响,试验测量方便,测试精度有保证.利用该装置研究点接触下不转速和不同载荷所对应的电阻和摩擦因数,并考察两者的变化规律.试验结果表明,摩擦因数与电阻的变化存在较强的关联性.结合Dowson润滑状态的划分方法,对点接触润滑状态进行划分,并绘制了相应的润滑状态图.结果 表明,该装置可对润滑状态进行精确划分,为润滑状态研究、润滑油品质鉴定等提供一种新的思路.

Interference connection is an effective method for improving the fatigue life of bolt connections. In this paper, a new method of interference connection was designed based on the shape memory effect of shape memory alloy. Using the method of numerical simulation, a finite element model was established to analyze the stress–strain rule of the bolt and the hole wall under different interference fit sizes. The results show that the stress concentration is formed at the orifice of the connecting plate. When the interference fit size is less than 1%, the connection hole has elastic deformation. When the interference fit size is 1.5%, the hole wall has plastic deformation. When the interference fit size is 2.5%, the maximum stress on the connecting plate is close to the tensile limit of the material. If the interference fit size continues to increase, the strength of the connection structure will be damaged. The connection experiments with different interference fit size were designed, and the interference force was calculated by the pull-out force. The experimental results were compared with the numerical simulation results. The change trend of the interference force with the interference fit size is consistent, which verifies the rationality of the finite element simulation.

本文主要介绍了大连海事大学创新教育基地的建设情况及经验做法,重点论述了该基地实施“兴趣驱动、自主实践、社团引领、开放共享、特色选育”的建设模式的成功实践,以及“三位一体、三个层次、三种模式、三个途径”的创新型人才培养机制,并就如何实现基地的可持续发展提出了具体建议.

为提高轮机工程专业学生的识读图样能力,把元认知策略的基本原理与识读图样教学相联系,提出基于元认知策略的识读图样教学方法. 运用试验对比的方法对轮机专业的两个班级进行教学试验,结果表明,利用元认知策略可以提高识读图样的能力和元认知水平,从而更好地进行后续专业课程的学习.

结合轮机专业工程制图的课程特点，通过活动教学与传递教学的比较，形成两者在工程制图课堂的和谐统一，建立活动教学与传递教学融合的教学模式，既保证基础理论的深度和广度，又兼顾实践能力、创新能力的培养。

大连海事大学教学督导组成立于1993年，至今已经历了20个春秋。20年来，教学督导组通过开展课堂教学评价和各种专项检查等工作，较好地发挥了督查、评估、咨询、指导的作用，有效地促进了学校教育教学质量的提高。教学督导组成为大连海事大学教学质量保障体系的一个重要组成部分。

The virtual assembly of purifier was achieved based on Division Mockup.The architecture of the virtual assembly system was proposed.Some key technologies as the form transformation between CAD software and Division Mockup,the interactive assembly process,the process planning compiled were researched.At last the assembly system for proving and training came true.

在简要阐述质量管理体系的基本理论的基础上,以大连海事大学的质量管理体系建立与运行情况为背景,探讨高等学校建立实施内部质量保障体系、促进本科教学质量不断提高、保障人才培养质量、营造高校质量文化的良好氛围的具体实践。

介绍徒手绘制工程图在培养学生创新精神、提高学生工程素质方面的作用,提出在工程图学课程中加强徒手绘图训练的必要性。结合教学实践,讨论影响徒手绘图教学的关键问题,并对其解决办法作了探讨。

Engine room of a ship is an environment scattered numbers of components. Pipe-routing arrangement should meet various requirement or constraints referring to either properties of individual components or relationships between components. The models of environment and components must be simplified by appropriate method to ensure an accurate and effectual design. An approach was proposed to construct the simulation environment for 3D pipeline design in ship engine room. The approach proceeds through 3 steps. First, the number of constrains is reduced by free space modeling method. Then, the proposed environment is divided into smaller modules. The final step is model simplification. The research aims at rapid construction of the scene for pipe routing arrangement, which is a prerequisite for a modern simulation-based approach. Finally, an example is presented to validate the effect and validity.

Notice of Retraction After careful and considered review of the content of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE's Publication Principles. We hereby retract the content of this paper. Reasonable effort should be made to remove all past references to this paper. The presenting author of this paper has the option to appeal this decision by contacting TPII@ieee.org. The main character of pipe route arrangement of a ship is to search a feasible path that connects given locations and avoids all obstacles in an engine room environment scattered with equipments and components, at the same time, the selected route should meet special evaluation conditions. Spatial effect is an important factor in the evaluation of pipelines, but is ignored in most existing optimize algorithms or the given methods are too complicated. Orientation-location distribution algorithm is presented to evaluate the spatial effect of pipe-routing. According to the location and direction of pipeline, different spatial effect coefficients are given and used to cost modification of routes to get the optimum layout. The presented algorithm is simple and feasible.

In this paper, we develop a model of shipbuilding supply chain network, including three tiers: raw materials and accessory products suppliers, shipbuilding centers (i.e. shipyard), the shipowner. In the normal course of shipbuilding, production is mainly carried out by meeting the needs of the end-user (i.e. the ship-owner). Under these conditions, decision-makers are analyzed in target, at last the optimization of the model by using the theory of variational inequalities and the numerical example are given.

In this paper, we present a green reverse supply chain supernetwork model, which consists of I manufacturers, J distributors, M markets and N recyclers. Hereon this base, the optimality conditions for the manufacturers, distributors, the consumers and the recyclers are established respectively using the variational inequalities. Then we describe the optimization situation for the supply chain supernetwork model and get the stationary points for this situation. An example is illustrated to validate the utility of the supply chain supernetwork model in the last part.

In order to implement the automized pipe route layout with artificial intelligence technology,based on the study of references,layout environment and the simplified representation methods of equipment are given.The obstacles of layout are represented by informationally-complete product models to overcome the large computational demand for checking the interference of models and to reduce the number of design constraints.The design environment is separated and the approximated layout platform is constructed quickly to make the least number of models in the scene.The efficiency and accuracy of the proposed approach are verified by an instance.

A multi-criteria and multi-decision e-commerce-based shipbuilding supply chain network model was established to optimize shipbuilding supply chain network.The current shipbuilding supply chain was expanded,and the knowledge of e-commerce was merged into the links of shipbuilding such as procurement of raw materials and the supply of auxiliary product,which enable enterprises to manage more effectively,save cost and enhance efficiency.Variational inequality approach was used to analyze the optimal behavior for all levels of decision-makers, and eventually the whole supply chain optimal state was obtained.Simulations show the reasonability of the proposed model.

The pebbling number of a graph G, f(G), is the least n such that, no matter how n pebbles are placed on the vertices of G, we can move a pebble to any vertex by a sequence of pebbling moves, each move taking two pebbles off one vertex and placing one on an adjacent vertex. Let p1,p2,…,pn be positive integers and G be such a graph, V(G)=n. The thorn graph of the graph G, with parameters p1,p2,…,pn, is obtained by attaching pi new vertices of degree 1 to the vertex ui of the graph G, i=1,2,…,n. Graham conjectured that for any connected graphs G and H, f(G×H)≤f(G)f(H). We show that Graham’s conjecture holds true for a thorn graph of the complete graph with every pi>1(i=1,2,…,n) by a graph with the two-pebbling property. As a corollary, Graham’s conjecture holds when G and H are the thorn graphs of the complete graphs with every pi>1(i=1,2,…,n).