It is very. difficuh to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect them during project implementation process. A GAs-based fully fuzzy optimal time-cost trade-off model is presented based on fuzzy sets and genetic algorithms (GAs). In tihs model all parameters and variables are characteristics by fuzzy numbers. And then GAs is adopted to search for the optimal solution to this model. The method solves the time-cost trade-off problems under an uncertain environment and is proved practicable through a giving example in ship building scheduling.

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The design of the ship cabin layout is a multi-objective comprehensive optimization problem, which needs to consider the location of the passage, cabin layout, space utilization ratio, functional realization, comfort, safety, and so on. In this paper, an improved tabu-criterion genetic algorithm for the intelligent design of ship cabin layout is proposed. According to the characteristics of ship accommodation cabin layout design, a ship deck layout area model and a multi-objective optimization model including relative location model, absolute location model, and ergonomic constraint model are established. The neighborhood transformation criterion and tabu-criterion of tabu search algorithm are introduced into genetic algorithm to advance the local search ability of a genetic algorithm. At the same time, a new genetic algorithm coding method is proposed to avoid the generation of illegal solutions in cabin layout sequence crossover and mutation operation. The improved genetic algorithm can effectively improve the local search ability of a genetic algorithm and make the algorithm converge to the optimal solution as soon as possible at the later stage of calculation. Finally, the simulation results verify the feasibility and efficiency of the proposed intelligent design method for ship accommodation cabin layout.

The paper studies the tearing algorithm in DSM, which is a useful tool to develop the product plan. This paper determines the iteration sequence of initial tasks in coupling set by introducing weight to DSM based on the flowing direction and the traffic of information. Combined DSM with Critical Path Method, the paper adjusts unreasonable tasks. The improved DSM method has been successfully applied into the development of the Ship Design Plan Management System of Dalian Heavy Industry Ship Yard. Keywords-Design Structure Matrix (DSM) develop plan plan optimization

With the increase of LNG power ship, the structure form of the fuel tank has been paid more attention. In this paper the advantages and disadvantages of LNG powered ship fuel tank with double shell tank structure or independent C type single shell tank structure are discussed from the initial evaporation rate control and the construction cost. According to the characteristics of the fuel tank for LNG power ship, the weight of the steel structure for the double shell fuel tank and the single shell fuel tank is calculated based on the design of four different kinds of fuel tanks, and the evaporation rate is simulated and predicted by use of ANSYS finite element software. Through the comparative analysis, it is found that the two kinds of structure can both meet the requirements of the specification. Under the condition of the same volume, shape and thickness of the insulation layer, the weight of the double shell tank structure is about two times as that of the single shell tank structure, while the evaporation rate about a quarter.