Xing Sun

Multiparameter Sensitivity Analysis of Operational Energy Efficiency for Inland River Ships Based on Backpropagation Neural Network Method

With the introduction of energy efficiency operational indicator (EEOI) to inland river ships, a multiparameter sensitivity analysis method was proposed to analyze the parameters affecting the operational energy efficiency of inland river ships. On the basis of experimental data, a model based on a backpropagation artificial neural network (BP-ANN) for predicting the EEOI was set up. The accuracy of this predictive model was verified. On the basis of weights and threshold values of each variable parameter gained in the trained BP-ANN, a Garson algorithm was used for calculating the parameter sensitivity factors. Results showed that, besides the engine speed, the environment conditions would also play a big part in the operational energy efficiency of inland river ships. The conclusion provides a foundation for engaging the energy efficiency improvement strategies for inland river ships.

Study of energy efficient navigation method for inland ship: A cruise ship case

According to the navigation characteristics of the inland ship, a multiple-constrained model of minimum fuel consumption is established. Some information collection sensors are amounted on this ship in order to obtain the research data. Through analysis and process of these data, the regression functions between main engine fuel consumption and shaft revolution speed and between ship speed to water and revolution speed are obtained. Take the typical navigation leg for example; the model is resolved using LINGO software. Next, the energy efficient methods are further studied in two aspects that is the optimization of the navigation time and the working number of the main engine. The research results indicate that ships fuel consumption can be efficiently reduced by extending the navigation time and reducing the working number of the main engine.

Clustering of the inland waterway navigational environment and its effects on ship energy consumption

This article examines the distribution characteristics of the navigational environment in the Yangtze River trunk line using several information collection sensors installed on ships that navigate in this line. Through experiments on these ships, data of energy consumption and the navigational environment are collected. Water flow and waterway depth are proved to be the main influencing factors on the ship energy consumption via Spearman’s correlation analysis. Next, data of water velocity and waterway depth that cover the entire trunk line are graded using the k-means clustering algorithm. To build an evaluation matrix of navigational environment, the frequency distribution of each grade in different Yangtze River legs is counted statistically, and on this basis, similar legs are clustered using the hierarchical clustering algorithm. In this way, the waterway partition in the Yangtze River trunk line is completed. Furthermore, the distribution of the energy consumption of ships in different legs is also calculated. The study results indicate that not only the navigational environment of the Yangtze River trunk line but also the energy consumption level of ships have distinctive regional differences. Finally, the laws of the Yangtze River navigational environment are analyzed, and the corresponding energy-saving navigation strategies are proposed, which are useful for crews to operate their ships in energy-efficient and safe conditions.

Research on the calculation methods of wind load coefficients of inland cruise ship

It is of great significance for the research of wind load in energy saving and emission reduction as wind load is one part of the ship total loads. An inland cruise ship is chosen as a research object, the wind loads on the ship including longitudinal and transverse forces and the yaw moment are calculated in wind angle of 0-180° by using CFD method, and then the numerical result is compared with those from empirical formula calculations such as Fujiware method, Blendermann method and Isherwood method. On this basis, the numerical flow field of the ship is analyzed. The result shows that wind load coefficients vary greatly with the coming wind angles; with the results from the four methods, it is concluded that the numerical calculations agree with Blendermann method very well, while Isherwood method has large discrepancy with the rest of the three methods. It should be mentioned that the wind moment could be obtained according to actual wind environment by using the method presented in this paper which could offer help for ship designing and stability assessing and the pressure distribution chart of the ship could provide reference for the optimal design of the superstructure of the ship by the CFD method used in this paper.

Navigation Environment Factors for the Investigation and Evaluation of Water Traffic Safety in the Yangtze River

This work aims to investigate the state of traffic safety in the Yangtze River, taking the navigation environment factors into account. Since accident data can directly represent the water traffic safety situation to some extent, it is widely used to evaluate the water traffic safety in the Yangtze River. The absolute accident index and relative accident index are two kinds of reasonable assessment data, but they can hardly represent the actual situation in different waterways when the navigation environment is changed. To overcome this problem, the data envelopment analysis (DEA) is employed for the evaluation of water traffic safety aiming at different navigation environments in this paper. First, detailed accident data for 2009-2011 as officially issued by the Maritime Safety Administration (MSA) of China in four different waterways and three water levels is described. Moreover, the corresponding navigation environments are also analyzed. Then, the evaluation of water traffic safety is studied by applying the C 2 R and C 2 GS 2 models. Finally, the results of the theoretical models are compared with traditional methods. This method can evaluate the water traffic safety in different waterways. The traffic flow, traffic accident, and the level of water traffic safety can be evaluated more scientifically and precisely. In the face of different navigational environments and water-traffic safety situations, the MSA can use these data and/or conclusions to improve their management level.

Research on the Energy Efficiency Improvement for Existing Ships

For numerous existing ships, reducing fuel consumption is achieved mainly by applying operational measures rather than technical measures. This paper outlines the operational approaches for energy efficiency enhancement. Methodologies for calculating greenhouse gas emissions or fuel consumption are presented from three perspectives: international maritime transports, regional or national shipping, and individual ships. A description model between EEOI and environment factors or service conditions was developed. It is suggested that the energy efficiency management should be planned on the base of the relationship model between ship energy efficiency and input variables.

Research on Navigation Information Flow Architecture of the Three Gorges under the Support of Internet of Things

The Three Gorges section of Yangtze River is of great importance and complexity, where ship locks, ships and cargos constitute a complex transportation logistics system. This system concentrates a large amount of information, and some of the information changes with time. The obtaining manner and processing method of such information are both important content of the work, without which the whole system would be obstructed. With cluster analysis and relational grade analysis of the navigation information, the system operating situation can be obtained by observing the information stream, and the navigation information flow architecture of Three Gorges under the support of internet of things is built. Therefore the traffic flow and material flow can be predicted and analyzed, so better ship lock scheduling is achieved.