Fault Diagnosing System of Steam Generator for Nuclear Power Plant Based on Fuzzy Neural Networks

All kinds of reasons are analysed in theory and a fault repository combined with local expert experiences is establishedaccording to the structure and the operation characteristic of steam generator in this paper. At the same time, Kohonen algo-rithm is used for fault diagnoses system based on fuzzy neural networks. Fuzzy arithmetic is inducted into neural networks tosolve uncertain diagnosis induced by uncertain knowledge. According to its self-association in the course of default diagnosis. thesystem is provided with non-supervise, self-organizing, self-learning, and has strong cluster ability and fast cluster velocity.     

3-D computational method of wave loads on turret moored FPSO tankers

A three-dimensional method of calculating wave loads of turret moored FPSO (Floating Production Storage and Offloading) tankers is presented. The linearized restoring forces acting on the ship hull by the mooring system are calculated according to the catenary theory, which are expressed as the function of linear stiffness coefficients and the displacements of the upper ends of mooring chains. The hydrodynamic coefficients of the ship are calculated by the three-dimensional potential flow theory of the linear hydrodynamic problem for ships with a low forward speed. The equations of ship motions are established with the effect of the restoring forces from the mooring system included as linear stiffness coefficients. The equations of motions are solved in frequency domain, and the responses of wave-induced motions and loads on the ship can be obtained. A computer program based on this method has been developed, and some calculation examples are illustrated. Analysis results show that the method can give satisfying prediction of wave loads.     

The effect of plastic constraint on the initiation of ductile tears in shipbuilding structural steels

In this paper, the effect of plastic constraint on the initiation of ductile tears in four different shipbuilding structural steels has been experimentally studied by measuring the J-integral and crack opening displacement COD at initiation in three-point bend specimens with deep and shallow notches. Experimental results of seven groups of different strength alloy steels show that both Si and Ji values of ductile tear from the shallow crack specimens which have less constraint flow field are significantly higher than those of deeply notched specimens. Slip-line-field analysis shows that, for shallow crack, the hydrostatic stress is lower than that from standard deeply cracked bend specimen, which develops a high level of crack tip constraint, provides a lower bound estimate of toughness, and will ensure an unduly conservative approach when applied to structural defects, especially if initiation values of COD and J-integral are used.     

Simulation System Design of 3-D Panorama of Ship Motions in Wave

In this paper a 3-D panoramic simulation system of a ship is described which is developed with the MAXSCRTPT language and VC + + as programming tools on the platform of 3 Dsmax. The strip theory method is applied to the motion prediction of the mono-hull. The time history solutions of heave and pitch are obtained in the condition of head sea to provide the primary data on panoramic simulation. The simulation system has following functions: 1) digital simulation; 2 ) panoramic simulation; 3) environmental set-up; 4) render preview and output.     

Potential and benefits of AIS to Ships and Maritime Administrations

The Universal Automatic Identification System (AIS) provides a huge variety of potential applications and services which exceed the well known ship-to-ship data exchange. The purpose of this paper is to address the most important AIS services, in particular the AIS position report and the AIS safety-related and binary messages (“AIS telegrams”). The main issue is the impact of this new technology on the on-board use of AIS in collision avoidance (and its limitations) as well as the impact on shore-based services such as Vessel Traffic Service (VTS), port management and the need of an effective AIS network.     

Accessing the global seafaring labour market

As a global labour market exists for international shipping, a challenging issue facing this industry is to get access to reliable, accurate and timely information of seafarers’ demand and supply. Related to the deregulation environment and great variety in the availability and quality of relevant information, an enquiry into the global seafaring labour market is more complex than a national labour force survey. To cope with the challenge, a novel approach has been developed by the Seafarers International Research Centre (SIRC) at Cardiff University. Viewing capital (ship), labour (seafarers) and services (cargo or passengers) as interconnected and interwoven to each other, it collects and analyses crew lists from main ports world-wide, resulting in the creation of the first global seafarers database. The purpose of this paper is explain its methodological principles, and to illustrate its application potential. Taking the cruise sector as an example, research findings and methodological implications are highlighted.     

Maritime search and rescue: Benefit or burden for society?

Just twenty five years have passed since the International Maritime Organization (IMO) provided the legal and internationally harmonized framework for maritime search and rescue operations. While a number of nations only had to adapt their well-established national services it took great efforts for other nations to develop agencies able to fulfil or outstrip minimum requirements. However, the majority of nations (well aware of the humanitarian nature of that task) have been afraid to cope with this challenge and the related financial burdens since the benefits to local, regional, or even national economies are not always clear to the relevant national administrating authorities.     

The choice of speed and clearance for RAS on 3D method

In this paper, a 3D source distribution technique is used to calculate the coupled motions between two ships which advance in the wave with the same speed. The numerical results of coupled motions for a frigate and a supply ship have a good agreement with the experimental results. Based on the 3D coupled motions of two ships, a spectral analysis is employed to clearly observe the effect of speed, clearance and wave heading on the significant relative motion amplitude (SRMA) of two ships.The method presented in this paper will be helpful to select suitable clearance, speed and wave heading for underway replenishment at sea(RAS).     

Assessing asymmetric response effect of behavioral intention to service quality in an integrated psychological decision-making process model of intercity bus passengers: a case of Taiwan

This study introduces the concept of loss aversion to consumer behavioral intention at the personal psychological level to develop an integrative structural equation model for analyzing traveler psychological decision making. In this model, the relationship between behavioral intention and service quality is a non-smooth function based on the theory of loss aversion. The expectation service quality in the SERVQUAL model proposed by Parasuraman, Zeithaml, and Berry (PZB) serves as a reference point. This model can be applied to analyze the effect of non-smooth response of behavioral intention to service quality in a traveler psychological decision-making process model. Intercity travel among cities in Taiwan is used as an empirical example. Data were gathered in cities in Taiwan via a questionnaire survey, and the model was tested using path analysis performed by LISREL. The empirical result shows that all causal relationships are statistically significant. Service quality loss influences repurchase intention more than does Service quality gain. Finally, this study concludes by discussing managerial implications and suggesting directions for future research.