Analysis of the continuous berth allocation problem in container ports using a genetic algorithm

The optimal usage of berths plays a key role in raising the efficiency of container terminals. The berth allocation problem in a container terminal is defined as the feasible allocation of berths to incoming ships such that the total time that elapses between the arrival of the ships to their exit from their berths is minimized. In the transportation literature, the latter problem is usually formulated as a mixed integer programming model. Optimization methods, like the branch and bound algorithm, are efficient ways to solve this model but become absolutely unusable when the size of the problem increases. An advanced search method such as GA may be suited to such a situation. In this paper, a genetic-based algorithm is proposed for the problem. Computational results for two test problems (a small and a large-sized problem) are also presented. The results from the small test are also compared with the results obtained from the branch and bound algorithm.     

Ground travel mode choices of air arrivals at regional destinations: The significance of tourism attributes and destination contexts

The aim of this paper is to examine the air leisure arrivals’ ground travel mode choice in the context of their decision to disperse beyond the gateway. A stated choice experiment was designed to examine the dispersal and travel mode choice of leisure visitors arriving on air transport at Cairns. Results show that for a hypothetical public bus alternative, attributes such as ‘sightseeing opportunities’ and ‘driver quality’ were significant for trips made to less known destinations located south of Cairns, compared to destinations north of Cairns. Findings suggest that while travel mode attributes and trip characteristics are significant determinants of the mode choice of air leisure arrivals, the extent of their significance varied markedly across destinations. Although the data examined in this paper were collected in Cairns, this research should be of relevance to many regions interested in understanding the relationship between destination transport and dispersal of air arrivals.     

The nexus between port governance and performance

The diversity of port governance models in the world, sometimes even within the same country, has aroused the interest of researchers. This study is based on contingency theory to support the port governance model. The purpose is to understand the port governance model and the relation with port performance. There are three objectives: to analyze the port governance mechanisms; to analyze the port performance factors; and to understand the influence of the governance model mechanisms on port performance. A factorial analysis was used to determine the main components, and the methodology of the structural equation model was used to analyze a survey sample of 105 valid responses from specialists and managers of port user’s companies that operate in the main Portuguese ports. This study demonstrates that port governance model influences directly the port performance. The main contribution of this paper to the literature is providing a set of factors that public managers may decide when changing the characteristics of the port governance models to ensure their performance. It was also observed the approximation of the port expert vision of port governance with models described in literature.     

Simplified Technique for Predicting Offshore Pipeline Expansion

In this study, we propose a method for estimating the amount of expansion that occurs in subsea pipelines, which could be applied in the design of robust structures that transport oil and gas from offshore wells. We begin with a literature review and general discussion of existing estimation methods and terminologies with respect to subsea pipelines. Due to the effects of high pressure and high temperature, the production of fluid from offshore wells is typically caused by physical deformation of subsea structures, e.g., expansion and contraction during the transportation process. In severe cases, vertical and lateral buckling occurs, which causes a significant negative impact on structural safety, and which is related to on-bottom stability, free-span, structural collapse, and many other factors. In addition, these factors may affect the production rate with respect to flow assurance, wax, and hydration, to name a few. In this study, we developed a simple and efficient method for generating a reliable pipe expansion design in the early stage, which can lead to savings in both cost and computation time. As such, in this paper, we propose an applicable diagram, which we call the standard dimensionless ratio (SDR) versus virtual anchor length (L_A) diagram, that utilizes an efficient procedure for estimating subsea pipeline expansion based on applied reliable scenarios. With this user guideline, offshore pipeline structural designers can reliably determine the amount of subsea pipeline expansion and the obtained results will also be useful for the installation, design, and maintenance of the subsea pipeline.     

Past,present, and future of the satellite-based automatic identification system: areas of applications (2004–2016)

In 2016, the world shipping fleet grew by 3.5%. Even if the annual growth rate remains at its lowest since 2013, the global situation is still in overcapacity (UNCTAD 2016). Ninety percent of global trade, by volume, is done by sea. Monitoring this fleet helps with vessel navigation, informing to help avoid critical situations such as collisions, accidents leading to oil pollution, grounding, or ships in distress, but also because traffic management in congested areas is essential. For system wide management, in regions such as MPAs (marine protected areas), conservation is the key factor, and movements can be monitored and analyzed in order to determine illegal or suspicious activities, or in order to limit and/or divert traffic, to mitigate the risks to species subject to protection. It is among these efforts that the automatic identification system (AIS) can play a key role. Since 2004, this VHF transceiver-based reporting system, imposed by the International Maritime Organization (IMO), has shifted from a traditional vessel identification device to a tool used in a wide variety of applications. The most common uses are safety and security; these issues are quite visible in the media and may touch more people on a global scale (e.g., piracy, oil spills). Over the years, AIS has become, especially with the emergence of the satellite-based capture of the signal in 2011, a widely used tool for developing applications such as fisheries monitoring, marine conservation, air pollution forecasting and modeling, ballast water monitoring, invasive species transport, and many more. In this paper, we propose to review the peer-reviewed publications related to the uses and applications of the AIS.     

用于预报离岸管线膨胀的简化技术（英文）

In this study, we propose a method for estimating the amount of expansion that occurs in subsea pipelines, which could be applied in the design of robust structures that transport oil and gas from offshore wells. We begin with a literature review and general discussion of existing estimation methods and terminologies with respect to subsea pipelines. Due to the effects of high pressure and high temperature, the production of fluid from offshore wells is typically caused by physical deformation of subsea structures, e.g., expansion and contraction during the transportation process. In severe cases, vertical and lateral buckling occurs,which causes a significant negative impact on structural safety, and which is related to on-bottom stability, free-span, structural collapse, and many other factors. In addition, these factors may affect the production rate with respect to flow assurance, wax, and hydration, to name a few. In this study, we developed a simple and efficient method for generating a reliable pipe expansion design in the early stage, which can lead to savings in both cost and computation time. As such, in this paper, we propose an applicable diagram, which we call the standard dimensionless ratio(SDR) versus virtual anchor length(LA) diagram, that utilizes an efficient procedure for estimating subsea pipeline expansion based on applied reliable scenarios. With this user guideline,offshore pipeline structural designers can reliably determine the amount of subsea pipeline expansion and the obtained results will also be useful for the installation, design, and maintenance of the subsea pipeline.     

Vehicle mass as a determinant of fuel consumption and secondary safety performance: A comment

Attention is called to evidence that in collisions between vehicles of equal mass, and in single-vehicle collisions, there is unlikely to be a very strong effect of car size on injury severity, and that variation in crashworthiness within the set of car models of a given size has a much larger effect. Consequently, the secondary safety of a national fleet of small cars in the future could be as high as that of a national fleet of large cars today.     

Structural design of an outer tie rod for a passenger car

This study proposes a structural design method for an outer tie rod installed in a passenger car. The weight of the outer tie rod is optimized by using the aluminum alloy Al6082M, which is developed as a steel-substitute material, and applying structural optimization techniques. The high strength aluminum with improved mechanical properties was developed to reduce the weight of the outer tie rod. The newly developed aluminum alloy Al6082M is applied as the material of the outer tie rod. The static strength due to inertia force, durability and buckling performances are considered in the structural design of the outer tie rod. At the proto design stage of a new outer tie rod, it is cost-effective to utilize FE (finite element) analysis to predict each of these performances. In addition, the current trend in the structural design of automobile parts is to use optimization techniques to reduce the weights of the parts. First, for an arbitrary base design, the static strength, the life cycle and the buckling load are calculated to check whether the design satisfies its criteria. Then, the critical performance is selected so as to include its loading condition only in the optimization process. In this study, the metamodel based optimization process using kriging is adopted to obtain the minimum weight satisfying the critical design requirement. Then, the feasibility of the determined optimum shape is investigated against the other performances. Finally, the optimum design of outer tie rod is modified by considering forging efficiency. The performances of the final design are investigated through simulation and experiment.     

Development of a hardware in the loop simulation system for electric power steering in vehicles

In this paper, a hardware-in-the-loop simulation (HILS) system was developed before the development of an electric power steering (EPS) system in a vehicle. This study was focused on the establishment of the HILS system. Driving conditions are simulated with the HILS system. The actual steering input parameters are confirmed on the monitor while driving the HILS system. The steering forces observed in the simulation with the developed HILS system are similar to those in real vehicle tests. The developed HILS system can be applied in the development of various types of EPS systems.     

Experimental evaluation of SOF effects on EGR cooler fouling under various flow conditions

An experiment was conducted to characterize the effects of SOF on EGR cooler fouling. A removable singletube test rig combined with a soot generator was developed to represent an EGR cooler and diesel exhaust gas. The use of a soot generator, which controlled the size and concentration of soot particles, enabled independent variables to be completely controlled. Either n-dodecane or diesel lube oil as substitute SOFs were vaporized and injected into the test rig to evaluate their effects on the growth of PM deposits and the degradation performance of the EGR cooler. Coolant temperature, which seemed to be associated with SOF content, was chosen as an independent variable, and PM deposit mass per unit area and the effectiveness drop versus time increased as the coolant temperature decreased. The PM deposit mass per unit area and effectiveness drop had maximum values at a coolant temperature of 40°C for every n-dodecane injection rate. For substitute SOFs tested in this experiment, the deposit mass increased when either n-dodecane or diesel lube oil was injected, but the effect of lube oil was more significant. Diesel lube oil seemed to have a stronger effect on the reduction of thermal conductivity by filling pores in the deposits. When diesel lube oil was injected, the deposit mass per unit area increased 127% compared to dry soot without injection. The effectiveness drop after 10 hours increased only 12.5%.