Global ship risk profiles: Safety and the marine environment

This article uses visualization techniques to investigate global ship risk profiles and their changes over time. With a unique data set of 49,151 observations, the authors link changes in risk profiles to legislative developments and industry actions, as well as identify areas prone to general safety, loss of life, and pollution risks. Improved risk profiles over time have resulted from legislative measures, including the International Safety Management Code, the Oil Pollution Act, amendments to the International Convention for the Prevention of Pollution from Ships, and the introduction of port state controls and industry vetting inspections.     

Effects of wind strength and wave height on ship incident risk: Regional trends and seasonality

Oceanographic conditions like wind strength and wave height affect the risk of shipping incidents. Seasonal variations and trends in these effects are studied for weather-related incidents and pollution incidents, for six major ship types and for six regions across the globe. The employed database of more than five million observations combines information from various sources on oceanographic conditions, ship particulars, and incidents. The magnitude of wind and wave effects is found to vary by ship type, region, season, and period, and most of these effects are larger during the autumn and winter season and in recent periods.     

An epsilon-optimal algorithm considering greenhouse gas emissions for the management of a ship’s bunker fuel

This paper provides an algorithm to minimize the fixed ordering, purchase, and inventory-carrying costs associated with bunker fuel together with ship time costs; and environmental costs associated with greenhouse gas emissions. It determines the optimum ship speed, bunkering ports, and amounts of bunker fuel for a given ship’s route. To solve the problem, we use an epsilon-optimal algorithm by deriving a property. The algorithm is illustrated by applying it to typical sample data obtained and the effects of bunker prices, carbon taxes, and ship time costs on the ship speed are analyzed. The results indicate that the ship speed and CO₂ emissions are highly sensitive to the factors considered.     

Evaluation of total risk exposure and insurance premiums in the maritime industry

The empirical evaluation of maritime risk exposure is based on the monetary value at risk (MVR) that incorporates individual safety quality data of about 130,000 vessels, insurable values related to various potential damages, and proxies for fractions of values lost at incidents. MVR provides a tool to enhance strategic planning of maritime administrations and insurance providers, which is illustrated by a high level comparison of annual risk exposure with insurance premiums for 2010–2014. The analysis reveals a global annual insurable value of 30.6 trillion USD with associated annual MVR of 38.8 billion USD for very serious and serious incidents. Although oil tankers show the highest risk exposure (1.75 million USD per tanker per year), safety qualities are found to be best for this ship type (1.4% annual incident risk) and worst for container vessels (2.8%). Annual growth rates in total risk exposure are mostly positive with highest value for dry bulk carriers (27.8%), whereas risk exposure tends to decline for pollution of oil tankers (−2.0%) and passenger vessels (−11.3%), and for loss of life of oil tankers (−1.9%) and dry bulk carriers (−1.4%). Comparison across administrative dimensions reveals that most risk exposure lies with old open registries and with beneficial owners and the Document of Compliance companies located in high income countries. Comparison with global insurance premiums suggests reasonably adequate coverage of maritime risks (excluding cargo) with under-insurance of risk by around 5% (about 1 billion USD per year), with some uncertainties remaining for actual loss fractions of the involved damages.     

Comprehensive Review of the Maritime Safety Regimes: Present Status and Recommendations for Improvements

Abstract

This article presents a comprehensive review of the maritime safety regimes and provides recommendations on how to improve the system. The results show a complex legal framework which generates a high amount of inspections and overlapping of inspection areas where no cross‐recognition is established by the various stakeholders. While the safety system seems to be successful in eliminating substandard vessels and while average insurance claims costs are substantially lower for inspected vessels than non‐inspected vessels, the results indicate that the economic conditions of the shipping market also have an effect on safety quality besides the frequency of inspections. No significant differences can be found between industry inspections and port state control inspections with respect to decreasing the probability of casualty. The system could be made more effective by combining data sources on inspections and using them respectively to improve risk profiling and to decrease the frequency of inspections performed on ship types such as tankers. The results further indicate a lack of proper implementation of the International Safety Management Code (ISM code) and conventions with reference to working and living conditions of crew (ILO 147). A revision of the ISM code and more emphasis on enforcement of ILO 147 could further enhance the level of safety at sea. The authors would like to thank several inspection regimes for their cooperation in providing inspection data and in allowing the observation of surveys and inspections on 26 vessels. In addition, the authors would like to acknowledge the data providers for the casualty data, Clarksons for the economic data as well as two P&I Clubs in making data on insurance claims available.     

船舶溢油故障树分析与事故案例查询系统开发研究

根据故障树分析理论,基于MATLAB/GUI平台,构建了船舶溢油故障树分析与事故案例查询系统。该系统可实现针对船舶溢油事故发生原因和概率的定性和定量分析、及事故案例的多条件筛选查询功能。利用构建的系统对船舶碰撞导致溢油事故故障树模型进行了最小割集、顶事件概率和底事件重要度的求解分析,结果表明该系统操作简便,计算耗时少,结果准确,可以为船舶溢油事故风险分析提供辅助工具,具有很好的实用价值。     

Segment-based alteration for container liner shipping network design

Container liner shipping companies only partially alter their shipping networks to cope with the changing demand, rather than entirely redesign and change the network. In view of the practice, this paper proposes an optimal container liner shipping network alteration problem based on an interesting idea of segment, which is a sequence of legs from a head port to a tail port that are visited by the same type of ship more than once in the existing shipping network. In segment-based network alteration, the segments are intact and each port is visited by the same type of ship and from the same previous ports. As a result, the designed network needs minimum modification before implementation. A mixed-integer linear programming model with a polynomial number of variables is developed for the proposed segmented-based liner shipping network alternation problem. The developed model is applied to an Asia–Europe–Oceania liner shipping network with a total of 46 ports and 11 ship routes. Results demonstrate that the problem could be solved efficiently and the optimized network reduces the total cost of the initial network considerably.     

Competing risks analysis on traffic accident duration time

Different clearance methods in traffic accident management lead to varied duration distributions. Apart from investigating the influence of various factors associated with accidents on the duration of such accidents using different clearance methods, this study also examines the cumulative incidence probability. We used traffic accident data obtained for 12 months from the Fourth Ring Expressway main line in Beijing to develop a subdistribution hazard regression model, which can assess the risk factors of two clearance methods. The regression results show that the different factors have statistically significant effects on the duration of two accident groups with different clearance methods; furthermore, opposite effects occur even for some factors that have a strong effect on both accident groups. For example, an accident involving a taxi extends the duration time with clearance method 1; in comparison, the accident is shorter with clearance method 2. The predicted cumulative incidence curves of the two types of clearance methods are shown as examples, with stratification based on the influence factors (taxi involved, season). Finally, the Gray test of the cumulative incidence functions and the log‐rank test of the Kaplan–Meier estimates of the survival functions are compared, in order to demonstrate the importance of using proper methods for analyses. Copyright © 2014 John Wiley & Sons, Ltd.     

Maritime routing and speed optimization with emission control areas

Strict limits on the maximum sulphur content in fuel used by ships have recently been imposed in some Emission Control Areas (ECAs). In order to comply with these regulations many ship operators will switch to more expensive low-sulphur fuel when sailing inside ECAs. Since they are concerned about minimizing their costs, it is likely that speed and routing decisions will change because of this. In this paper, we develop an optimization model to be applied by ship operators for determining sailing paths and speeds that minimize operating costs for a ship along a given sequence of ports. We perform a computational study on a number of realistic shipping routes in order to evaluate possible impacts on sailing paths and speeds, and hence fuel consumption and costs, from the ECA regulations. Moreover, the aim is to examine the implications for the society with regards to environmental effects. Comparisons of cases show that a likely effect of the regulations is that ship operators will often choose to sail longer distances to avoid sailing time within ECAs. Another effect is that they will sail at lower speeds within and higher speeds outside the ECAs in order to use less of the more expensive fuel. On some shipping routes, this might give a considerable increase in the total amount of fuel consumed and the CO₂ emissions.     

Routing and fleet deployment in liner shipping with spot voyages

The routing, scheduling and fleet deployment is an important integrated planning problem faced by liner shipping companies which also lift load from the spot market. This paper is concerned with coordinating the decisions of the assignment of ships to contractual and spot voyages, and the determination of ship routes and schedules in order to maximize profit. We propose a new model for representing voyages as nodes of a directed graph which is used to build a mixed integer programming formulation. Besides contractual and spot nodes, another type of node is put forward to represent a combination of a contractual voyage with one or more spot voyages. In addition, the concept of dominated nodes is introduced in order to discard them and reduce the effort of the search for an optimal solution. A set of test problems has been generated taking into account real world assumptions. The test problems are solved by an optimization software and computational results are reported. The results show the potential of the approach to solve test problems of moderate size.     

Routing and scheduling of RoRo ships with stowage constraints

Roll-on/Roll-off ships are used for international transport of vehicles and other rolling equipment. We consider the problem where a ship sails between two geographical regions, picking up cargo in the first and making deliveries to the second. Several variations are considered with optional cargoes, flexible cargo quantities, and ship stability restrictions. Decisions must be made regarding the route and schedule of the ship as well as the stowage of cargo onboard. The problem is modeled as a mixed integer program, which has been solved using Xpress. In addition, a tailor made heuristic procedure is built using components from tabu search and squeaky wheel optimization. Extensive computational results are presented, showing that the heuristic is able to handle realistically sized problem instances.     

On two speed optimization problems for ships that sail in and out of emission control areas

This paper deals with two speed optimization problems for ships that sail in and out of Emission Control Areas (ECAs) with strict limits on sulfur emissions. For ships crossing in and out of ECAs, such as deep-sea vessels, one of the common options for complying with these limits is to burn heavy fuel oil (HFO) outside the ECA and switch to low-sulfur fuel such as marine gas oil (MGO) inside the ECA. As the prices of these two fuels are generally very different, so may be the speeds that the ship will sail at outside and inside the ECA. The first optimization problem examined by the paper considers an extension of the model of Ronen (1982) in which ship speeds both inside and outside the ECA are optimized. The second problem is called the ECA refraction problem, due to its conceptual similarity with the refraction problem when light travels across two different media, and also involves optimizing the point at which the ship crosses the ECA boundary. In both cases the objective of the problem is to maximize daily profit. In addition to mathematical formulations, examples and sensitivity analyses are presented for both problems.     

Accident severity analysis using ordered probit model

To reduce injuries in road crashes, better understanding is needed between the relationship of injury severity and risk factors. This study seeks to identify the contributing factors affecting crash severity with broad considerations of driver characteristics, roadway features, vehicle types, pedestrian characteristics and crash characteristics using an ordered probit model. It also explores how the interaction of these factors will affect accident severity risk. Three types of accidents were investigated: two-vehicle crashes, single vehicle crashes and pedestrian accidents. The reported crash data in Singapore from 1992 to 2001 were used to illustrate the process of parameter estimation. Several factors such as vehicle type, road type, collision type, location type, pedestrian age, time of day of accident occurrence were found to be significantly associated with injury severity. It was also found that injury severity decreases over time for the three types of accident investigated.     

西江航道实行船舶定线制的可行性分析

船舶定线制是国际上通行的实行水上船舶交通管理的一种形式,它对于规范船舶的航路,避免船舶过多交叉航行,减少船舶交通安全事故具有重要意义。文章以西江实行船舶分边通航为例,对实行船舶定线进行了可行性分析,建议通过分流和分道来防止或减少船舶发生碰撞、搁浅、触礁等水上交通事故。     

The desulphurisation of shipping: Past,present and the future under a global cap

As from January 2020, the International Maritime Organization (IMO) is implementing a global 0.5% limit on the sulphur content of fuel, commonly known as the global sulphur cap. This limit is the latest policy in the efforts to reduce sulphur emissions from shipping, following the designation of emission control areas (ECAs) and other regional regulations. In this paper, a literature review is conducted of academic studies that have dealt with issues relating to the reduction of maritime sulphur emissions. Various recurring research themes are identified, spanning the areas of operations research, maritime economics and transport policy. The effects and implications of available compliance options are then analyzed from the perspectives of ship operators, shippers and consumers. Using lessons learned from the enforcement of ECA regulations, this is followed by an appraisal of various potential issues related to the enforcement of these new global regulations. It is found that a homogeneous enforcement regime is required to ensure a level playing field amongst ship operators and that the global sulphur cap may lead to serious market distortion, due to the potential short term rise of fuel prices. The paper concludes with a set of recommendations for future research on sulphur emissions from shipping in the aftermath of the global cap and, looking forward, to its relationship to the IMO strategy on the reduction of greenhouse gas (GHG) shipping emissions.     

在役输气管线的完整性评价方法

引入国外发展较好的完整性评价技术,从影响在役输气管线完整性的各种因素着手,对在役输气管线的完整性评价从安全性、可靠性和风险性3个方面进行分析。管道完整性评价是将3种评价方法有机结合起来,深入研究将大大减少管道事故的发生,并减轻事故造成的后果,从而为在役输气管线的完整性管理提供可靠的依据。     

Dynamic optimization of ship energy efficiency considering time-varying environmental factors

Nowadays, optimization of ship energy efficiency attracts increasing attention in order to meet the requirement for energy conservation and emission reduction. Ship operation energy efficiency is significantly influenced by environmental factors such as wind speed and direction, water speed and depth. Owing to inherent time-variety and uncertainty associated with these various factors, it is very difficult to determine optimal sailing speeds accurately for different legs of the whole route using traditional static optimization methods, especially when the weather conditions change frequently over the length of a ship route. Therefore, in this paper, a novel dynamic optimization method adopting the model predictive control (MPC) strategy is proposed to optimize ship energy efficiency accounting for these time-varying environmental factors. Firstly, the dynamic optimization model of ship energy efficiency considering time-varying environmental factors and the nonlinear system model of ship energy efficiency are established. On this basis, the control algorithm and controller for the dynamic optimization of ship energy efficiency (DOSEE) are designed. Finally, a case study is carried out to demonstrate the validity of this optimization method. The results indicate that the optimal sailing speeds at different time steps could be determined through the dynamic optimization method. This method can improve ship energy efficiency and reduce CO₂ emissions effectively.     

Evaluating Key Resources and Capabilities for Liner Shipping Services

Abstract

This paper empirically evaluates key resources and capabilities in the liner shipping context. Based on a factor analysis, three resource dimensions are identified: marine equipment, information equipment, and corporate image; whereas seven capability dimensions are identified: purchasing, operation, human resource management, customer service, information integration, pricing, and financial management. The findings suggest that operation capability is perceived as the most important dimension, followed by customer service, human resource management, information integration, pricing purchasing, and financial management. Results indicate that four dimensions are found that significantly differ between shipping companies and agencies: marine equipment, information equipment, operation, and information integration. The theoretical and managerial implications of the research findings are discussed.     

Willingness-to-pay for road safety improvement

Few studies have explored, to date, the issue of the monetary valuation of non-fatal injuries caused by road traffic accidents. The present paper seeks to raise interest in this question and to estimate, by contingent valuation, French households’ willingness-to-pay (WTP) to improve their road safety level and reduce their risk of non-fatal injuries following a road accident. More precisely, a Tobit and a type-II Tobit model were estimated to identify factors for WTP. The results highlighted the significant positive influence of injury severity on WTP. Experience of road traffic accidents seemed to play an important role, positively influencing valuation of non-fatal injury.     

Methodological aspects for modeling the environmental risk of transporting hazardous materials by road

The main objective of this paper is to establish the procedures necessary to the development of a model for the environmental risk assessment of accidents involving Transporting Hazardous Materials by Road (THMR). Quantifying the environmental risk is useful in identifying areas with a high risk of accidents, which can be later discarded as main routes; orienting efficient emergency response operations; and assessing policies aimed at reducing these risks. Taking this into consideration, this study endeavors to identify the methodological aspects make possible the assessment of the impacts that arise from accidents involving the transportation of hazardous materials by road and to implement such methodological aspects in a Geographic Information System (GIS).