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Fuel cost is an important part of voyage cost, and fuel replenishment strategy is an important decision affecting the operating cost and benefit of shipping companies. A mixed integer nonlinear programming model of fuel supply for LNG dual-fuel ships is established to expand the research scope of fuel supply in the shipping industry to minimize fuel cost. In this paper, the genetic algorithm is improved, the solving steps are designed, and the validity of the model and the algorithm are verified by example analysis. The results show that as long as the LNG price does not exceed 120% of the LSHFO price, the LNG dual-fuel ship can still reduce the fuel cost during the voyage. The lower the LNG price, the larger the LNG fuel tank capacity and the higher the proportion of fuel cost saved. When the fuel market fluctuates, the model can provide a scientific basis for shipping companies to determine the type of ship fuel, optimize the speed, and select the fuel port and fuel volume.

To enhance the bridge resilient performance, a novel re-centering seismic isolator (RSI) is developed by incorporating damping enhanced (DE)-sliding-lead rubber bearing (LRB) with superelastic shape memory alloy (SMA), which functions with the yielding-sliding hysteretic mode. The numerical model of the novel RSI is developed in OpenSees platform and validated by comparing the numerical and experimental hysteretic loops of the superelastic SMA and DE-sliding-LRB. A parametric design procedure is proposed to determine the optimum parameters of the novel RSI system. A three-span continuous girder bridge is selected to investigate the response mitigation efficiency of the novel RSI system compared with LRB system under near-fault ground motions. A systematic parametric study is conducted to design the optimal parameters of the novel RSI system for bridges. Case study is conducted to investigate the effectiveness of the proposed design procedure and the novel RSI system for response mitigation of bridges. Results show that the damping capability is effectively enhanced by designing the friction coefficient of the sliding element. The novel RSI system can achieve dual mitigation of the displacement responses and base force in piers for bridges. Case study demonstrates the effectiveness of the novel RSI and parametric design procedure.

In large-scale game activities, the computer big data system is collected, and then large-scale real-time data collection, processing and control systems are used to bring mathematical algorithm models, and state information reliability algorithms are used to illustrate the system control machine design and its Implementation based on VMS. This article calculates the most by calculation. The main design ideas in the game mathematical model, the research found that the system controller proposed by the system is a method to solve the multi-state process synchronization problem in the Client/Server computing system, and can effectively deal with the algorithm application research in the model.

The power conversion efficiency (PCE) of polymer solar cells (PSCs) can obviously be improved by plasmon resonance effects of noble metal nanoparticles. However, incorporating noble metal such as Ag and Au nanoparticles (NPs) can usually accelerate the deterioration of PSCs due to the diffusion of noble metal atoms, which would limit the potential application of plasmonic PSCs. PSCs with ferrocenedicarboxylic acid (FDA) modified Al-doped ZnO (AZO) layer compared to pure AZO layer can synchronously increase PCEs and ultraviolet (UV) and moisture stabilities. PSCs with Ag NPs doped Al-doped ZnO (AZO:Ag) increased to 10.20% of PCE from 9.08% PCE of the reference PSCs with pure AZO layer, but show inferior stability. Furthermore, PSCs with FDA modified AZO:Ag layer obtained 10.0% of PCEs and showed superior UV durability and moisture stability. PSCs with FDA modified AZO:Ag layer respectively maintain the original PCE values of 50% and 53% exposing UV light for 13 h and aging for 9 months at RH 10%, which are obviously higher than 36% and 34% of the original PCEs of PSCs with AZO:Ag layer. The results indicate that FDA modification is an effective strategy to solve the quick deterioration of plasmonic PSCs without evidently sacrificing PCEs.

Reduced graphene oxide bundles with sharp tips were fabricated by a simple approach with freeze-drying and hydrothermal reduction, and this approach could modify the surface topography of the field emission cathode and make more graphene bundles sharpen and aligned. This field emission cathode material displayed excellent field emission properties decreased from 2.9 V μm−1 to a low turn-on field of 0.8 V μm−1 at the emission current density of 10 μA cm−2. Sharp graphene emitter arrays have sharp protruded tips in abundance, leading to an enlarged field enhancement factor from 1683 to 10182, which was much better than those films prepared by other methods we adopted. It also revealed a good field emission stability with no degradation in the current for 3 h. We believe that this approach can enhance the field emission performance of graphene emitters, which could be widely candidate for various field emission applications.

Because of its extremely low permeability, cohesive soil is often regarded as a very important impermeable material in geotechnical projects. Therefore, further study of the mechanism of cohesive soil infiltration has a very far-reaching significance in the field of civil engineering. In this paper, with the concept of effective void ratio, the traditional formula of soil permeability coefficient is modified. Based on the fractal dimension of fractal theory, the function relationship between void ratio and fractal dimension was established. Based on this function, the fractal dimension was used to describe the effective void ratio of saturated clay, and the fractal theory is used to correct the empirical formula of permeability coefficient of saturated cohesive soil. The formula can be used to study the permeability of saturated cohesive soil and improve the theory of percolation and the solution of permeability coefficient.

End-to-end learning-based communications systems are more likely to achieve the global optimal performance. In this work, we implement a complete communications system as an end-to-end deep neural network, including transmitter, channel model, synchronization and receiver. There are a lot of issues which can result to the out of synchronization between the transmitter and the receiver, including sampling timing offset, sampling frequency offset and so on. Therefore, we focus on frame and timing synchronization in the end-to-end learning-based communications systems. Our results show that such an end-to-end learning-based communications system is robust to the impairments that arise from sampling frequency offset. An extra synchronization model based on the convolutional neural networks is introduced to achieve frame synchronization and compensate for the impairments which arise from sampling time offset and sampling time error. The performances of the synchronization model are evaluated from the symbol error rate and the frame header detection results. It can correctly detect most of the actual position of frame header, and it is about 2dB better than that of the direct correlation detection in the end-to-end communications systems.

To ensure the security of the cantilever construction and elevation template adjustment for cable-stayed bridge, finite element model of guyed form traveller of Gan-zhu-xi cable-stayed bridge was built. At first, two models are considered under actual construction stage, then a static load test was carried out. The theoretic result was in consistent with the results from field test. It also showed that the optimal design was reliable and the operational performance could meet the construction requirements. Elevation template can be determined by the deflection measured results.

In order to study the mechanism of the annular Pre-stressing steel strands applied to cable-pylon anchorage zone, a full-scale model test and finite element analysis were conducted. Through the research on the full-scale model test of the U-shaped annular Pre-stressing steel strands for the Anchorage Zone of Guangzhou Bridge, the prestressing technique for the U-shaped annular Pre-stressing steel strands was investigated, and the stress distribution in the model were measured and analyzed. It can be found that the elongation of the U-shaped pre-stressing steel strands is greater than the actual theoretical limit, and the results of some project cases also showed that it is a common phenomenon. Finally, the reasons for thus problems and relative suggestions are proposed, they can be used as a reference to engineering practice.

Efficient inverted polymer solar cells (PSCs) with two-step deposited zinc oxide (ZnO) cathode interfacial layer are developed by magnetron sputtering method. The first-step ZnO layer sputtered with Ar gas has lower bulk resistance due to increasing oxygen vacancy. The second-step ZnO layer sputtered with O2/Ar ratio (1:7) gas can obtain lower contact barrier and superior interface properties at ZnO/photoactive layer interface. The power conversion efficiencies of inverted poly(3-hexylthiophene) and phenyl-C61-butyric acid methylester (P3HT:PCBM) based PSCs with 11 nm/4 nm and 50 nm/10 nm ZnO layers are, respectively, 4.08% and 3.13%, which are obviously higher than that of corresponding PSCs with O2/Ar gas sputtered 15 nm and 60 nm ZnO layers. The conduction band level of ZnO film with O2/Ar sputtering gas is higher, 0.14 eV, than that of ZnO film with only Ar layer derived from ultraviolet photoelectron spectroscopy and optical band gap of ZnO films. The capacitive behavior of PSCs with 30 nm and 60 nm layers indicates that two-step sputtered ZnO layer can efficiently enhance electron transport ability of bulk ZnO layer and attenuate electron accumulation at ZnO/P3HT:PCBM interface. Lower reverse saturation current and higher shunt resistant of PSCs with two-step sputtered ZnO layer demonstrated that the defects penetrating into the whole ZnO layer can be inhibited.

Four-layered plasmonic structures of glass/Au/TiO2/NaYF4:Yb, Er, Gd nanorods were fabricated and tremendous improvement in upconversion luminescence (UCL) was observed under infrared 980 nm excitation. The TiO2 film was used as an oxide spacer. The emission intensity of the upconversion (UC) nanorods was strongly modulated by the thickness of the TiO2 layer. The extent of modulation depended on the separation distance between the Au layer and UC nanorods. A maximum UCL enhancement of 192-fold was observed for one green emission (540 nm) when a 10 nm-thick TiO2 film was used; 150-fold was observed for the other green emission (521 nm) at the same thickness of TiO2; and 105-fold was observed for the red emission (654 nm) when a 7.5 nm-thick TiO2 film was used. Alteration of the radiative decay rate was demonstrated for the first time in measurements of the decay times of UC nanorods positioned at various distances from the Au layer. The light interaction and coupling between metal Au and UC nanorods is numerically studied. The UCL mechanisms of multilayer plasmonic structures are discussed. Experimental results are explained and correspond well with those of theoretical calculations.

The thermal stability of AZO/Al/Ag/Al/AZO (5A) compared with AZO/Ag/AZO (3A) electrodes was significantly improved by introducing a thin Al layer at the interface between Ag and AZO layers. The rapidly deteriorated sheet resistance of 3A compared with 5A electrodes is roughly consistent with the XRD results of weaker intensity of the (1 1 1) Ag peak of 3A after annealing for 20 h at 300 or 500 °C for 10 min. The improved thermal stability of the 5A electrode is ascribed to the limitation function of Al atoms on Ag diffusion into the AZO layer. The polymer solar cells based on 5A compared with ITO electrodes showed a similar efficiency.

The synthesis of diamond-like carbon (DLC) films at room temperature by Nd:YAG pulsed laser (532 nm) irradiation of a polymer precursor is presented. The structures of films with the laser fluence were investigated by Raman spectroscopy. The morphologies of the resulting samples were examined by scanning electron microscopy (SEM), and the mechanism of DLC phases converted from the polymer is discussed. Raman spectrum analysis and SEM results indicate that the polymer is converted into amorphous carbon (a-C:H) phases with fluence from 60 to 650 mJ/cm2 and crystalline diamond in amorphous carbon matrix phases with fluence above 650 mJ/cm2 by pulsed laser irradiation in an argon gas atmosphere. It is proposed that the conversion of DLC phases is related to the special diamond-like structure of the polymer, and the laser provides an efficient thermal source.

Using the outer product reduction coefficient of the ordinary permutation group, the authors have calculated the Clebsch-Gordan coefficient for the non-special Gel'fand basis of the graded unitary group SU (m/n) for the five-particle system.