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The ultraviolet emission line at 3.315 eV is observed at 8K in ZnO polycrystalline films and investigated by temperature-dependent photoluminescence spectra and cathodoluminescence spatial image. The relative intensity of 3.315eV emission line depends strongly on growth and annealing conditions. The cathodoluminescence image shows that the 3.315eV emission localizes on the surface and ridge of ZnO grain. These results suggest that the 3.315 eV emission attributes to Zn interstitials at the grain surface and ridge. This emission is stable in the range from 8K to 300K and contributes to the room temperature ultraviolet band.

Selecting optimization ship form scheme is an important content in the process of concept design of ship. Multi-objective fuzzy decision-making model for ship form demonstration is set up according to the fuzzy pattern-recognition theory. Weight coefficients of each target of ship form scheme are determined by information entropy and individual subjective partiality. This model is used to select the optimal ship form scheme, the example shows that the model is exact and the result is credible. It can provide a reference for choosing the optimization scheme of ship form.

In a general case, container ship serves many different ports on each voyage. A stowage planning for container ship made at one port must take account of the influence on subsequent ports. So the complexity of stowage planning problem increases due to its multi-ports nature. This problem is NP-hard problem. In order to reduce the computational complexity, the problem is decomposed into two sub-problems in this paper. First, container ship stowage problem (CSSP) is regarded as “packing problem”, ship-bays on the board of vessel are regarded as bins, the number of slots at each bay are taken as capacities of bins, and containers with different characteristics (homogeneous containers group) are treated as items packed. At this stage, there are two objective functions, one is to minimize the number of bays packed by containers and the other is to minimize the number of overstows. Secondly, containers assigned to each bays at first stage are allocate to special slot, the objective functions are to minimize the metacentric height, heel and overstows. The taboo search heuristics algorithm are used to solve the subproblem. The main focus of this paper is on the first subproblem. A case certifies the feasibility of the model and algorithm.

N-ZnO/p-Si heterojunctions are prepared by sputtering deposition of intrinsic ZnO films on p-Si substrates. Thicknesses of ZnO films are altered by varying the deposition time from 1 h to 3 h. The electrical properties of these structures are analysed from capacitance-voltage (C-V) and current-voltage (I-V) characteristics performed in a dark room. The results demonstrated that all the samples show strong rectifying behaviour. Photovoltaic property for the samples with different thicknesses of ZnO films are investigated by measuring open circuit voltage and short circuit current. It is found that photovoltages are kept to be almost constant of 320 mV along with the thickness while photocurrents changing a lot. The variation mechanism of the photovoltaic effect as a function of thickness of ZnO films is investigated.

ZnO:Al films have been prepared on p-type Si substrates by DC reactive sputtering. Hall measurement showed that the ZnO:Al films exhibited apparent n type conductivity. I-V characteristics in darkness and under illumination have been performed. It was found that the illumination reverse current increased rapidly with the applied voltage and was saturated at -1 V, which was obviously different from that in darkness. This phenomenon resulted from the photovoltaic effect of heterojunction. Furthermore, in order to investigate the mechanism of photovoltaic conversion, photoconductivity and photovoltage response spectra have been studied. It was found that the photocurrent decreased sharply when the wavelength was 380 nm, and the direction of photovoltage response also changed at this point. It was presumed that this phenomenon has a close relationship with the energy band structure of the heterojunction.