Editorial: Young maritime researchers—a note of respect

Globalization, liberalization, competition and spatial interaction are significant factors affecting the transformation of manufacturing industries worldwide. In the transportation and logistics industry, however, cooperation is becoming even more critical than competition in determining firms' efficiency. Cooperation has always characterized the liner sector in which strategic alliances, mergers and acquisitions have generated twin effects: notable increases in ship size and falls in freight rates. Meanwhile, the stevedoring industry is undergoing privatization-driven consolidation and the emergence of global pure terminal operators. This article focuses on vertical integration between global carriers and terminal operators. We address the following key current issues: 1. dedicated terminals as a strategy for cutting costs and controlling integrated transport chains;

2. the struggle for supply chain control, involving global carriers versus global terminal operators, driven by financial power and technical and managerial capability.

We close analysing one of the core problems of the market, namely the evolving role of the dedicated terminals. For the pure stevedores they represent an opportunity to secure a cargo, while in the hands of the liners they enable cost stability and the possibility to put pressure on pure terminal operators.     

Liner costs and pricing polices: a reconsideration of regulatory issues

A number of shipping analysts have adopted as a convenient approximations, the assumption that linear costa are homogeneous per unit of cargo. The paper points to recent evidence suggesting that considerable differences exist in the estimates of implicit marginal cost for various types of cargo, and re-evaluates the regulatory arguments which are based on the assumption of homogeneity of costs.     

Risk assessment: An introduction and critique

Abstract

Risk assessment is a methodology which has been used to evaluate the safety of major public projects, notably aerospace programs, liquefied natural gas import facilities, and nuclear power plants.

This article begins with a review of public attitudes toward risk and then describes the basic components of a risk assessment. Subsequent critical analysis suggests the pitfalls inherent in the technique, especially in regard to the establishing of a criterion of safety against which the results of a risk assessment will be compared. The author identifies three such criteria and rejects two of them, including the one most commonly used in federal government agency decision‐making, as unreliable or philosophically unacceptable.

The article concludes with comments on the applicability of risk assessment in coastal zone management.     

A stochastic model for highway traffic

A nonlinear model for unidirectional flow of heavy traffic on a two-lane highway is considered. Features such as entrance, exit and lane transfer with time-dependent parameters are incorporated into the model, with the result that a number of previous models employed in the study of traffic flow become special cases of ours. Using the method of system-size expansion, an asymptotic analysis of the problem, including the time evolution of both deterministic and stochastic aspects of the traffic system, is carried out. In addition, a scheme for obtaining the moments of the probability distribution for systems of finite size is developed and a comparison is made with the exact results appropriate to a particular model. The agreement between the two sets of results turns out to be remarkably good.     

Comparative environmental impacts of electric bikes in China

Electric two-wheelers have become a significant mode of transportation in China in the past decade. Though marketed and publicized by some as zero-emission vehicles, little past research has been done to quantify the environmental impacts of electric two-wheelers in China. This paper quantifies some of the environmental impacts of the production processes and use phase of electric two-wheelers and compares them to the environmental impacts of competing modes, including bicycles, buses, motorcycles and cars. The use phase emissions are quantified geographically with significantly higher emissions in coal rich regions, compared to regions relying more on hydropower. The results show that electric two-wheelers emit several times lower pollution per kilometer than motorcycles and cars, have comparable emission rates to buses and higher emission rates than bicycles. Lead is one pollutant on which electric two-wheelers perform poorly, because of their use of lead acid batteries.     

Spatial heterogeneity and temporal dynamics of particles, bacteria, and pEPS in Arctic winter sea ice

Abundances of particles, total bacteria, and particulate extracellular polymeric substances (pEPS) in Arctic sea ice were tracked through a winter season to examine the impact of combined extremes of low temperature and high salinity on the prokaryotic microbial community. Three horizons, centered at depths of 25, 45, and 65 cm from the ice surface, with mean seasonal temperatures of − 20, − 17, and − 13 °C, respectively, were sampled 16 times over the course of 12 weeks. Microscopic counts of bacteria (stained with DAPI) and particles (stained with acridine orange) reflected the dynamic conditions of the growing ice sheet, with greater abundances and variability in the upper ice horizons compared to the lower. The trend of higher particle and bacterial abundances in the upper ice was corroborated by several full-depth profiles taken during the expedition, which also displayed significantly decreasing cell abundance with depth. Bacterial abundance declined slowly and significantly with time in the upper and middle ice horizons, but not in the lowest, suggesting that much of the prokaryotic microbial community is resilient to extreme environmental conditions. We found that pEPS concentrations increased significantly with time and with decreasing temperatures in all depth horizons, which may lend support to the argument that sea ice bacteria produce EPS in situ as a cryoprotectant.     

Factors associated with crashes due to overcorrection or oversteering of vehicles

The objective of this research is to identify factors associated with crashes due to overcorrection or oversteering of vehicles. Crash data was collected from 2011 to 2013 for the State of North Carolina in the United States. Logistic regression modeling was used to analyze crash data because of the dichotomous nature of the dependent variable (overcorrection or oversteering). The crash involvement due to overcorrection or oversteering of a vehicle decreased as the age of the driver increased. Drivers are 2.22 times more likely to overcorrect or oversteer when ill, 3.44 times more likely to overcorrect or oversteer when under fatigue, and 1.61 times more likely to overcorrect or oversteer when fallen asleep compared to normal physical conditions. Overall, driver characteristics and speed limit tend to play a major role in overcorrection or oversteering of vehicles. Programs to reduce impaired driving might help in the reduction of overcorrection or oversteering related crash fatalities or injuries. Additionally, training and driver education programs focusing on identified factors associated with crashes due to overcorrection or oversteering of vehicles will benefit drivers on how to respond during emergency or panic situations.     

Aging characterization of metals for exhaust systems

The mechanical characteristics of four materials used in automotive exhaust systems have been compared after an aging treatment to evaluate the combined effects of thermo-mechanical fatigue and corrosion. For this purpose, an experimental aging procedure has been developed. This procedure is composed of chemical, thermal and mechanical cycles, which are combined and repeated to simulate the actual operating conditions of automotive exhaust systems. Three austenitic steels (AISI 309, AISI 316Ti, and AISI 321) and a nickel-based alloy (Inconel 625) are tested. The results show that Inconel 625 and AISI 309 are less affected by the aging process than the other materials.