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1.
The study investigates determinants of vessel-accident bunker fuel spillage. A vessel-accident bunker spillage equation is estimated using Tobit regression and data of individual non-oil-cargo vessel accidents that were investigated by the US Coast Guard during 2001–2008. The results indicate that the bunker spillage of a freight ship and an offshore supply vessel accident will be greater than that of a passenger ship accident. Also, the bunker spillage of a non-oil-cargo vessel accident will be greater if the vessel accident is an abandonment and occurs at night, but less if the accident involves a vessel that has diesel propulsion and even less if the vessel has both diesel propulsion and a steel hull.  相似文献   

2.
While the literature has established macroeconomic determinants of shipping freight (charter) rates, there has been no systematic investigation of the microeconomic determinants of shipping freight rates. Therefore, the purpose of this paper is to investigate microeconomic determinants of freight rates in the dry bulk shipping market, using a large sample of individual dry bulk charter contracts from January 2003 to July 2009. Differences in freight rates across major dry bulk shipping routes, the geographical distribution of shipping activities around the world, and the duration of the laycan period of shipping contracts are also investigated. Estimated results suggest that the laycan period and dry bulk freight rates are interrelated and determined simultaneously. Furthermore, vessel deadweight, age and voyage routes are important determinants of dry bulk shipping freight rates, while determinants of the laycan period of chartered vessels include vessel age, freight rate level, and freight rate volatility.  相似文献   

3.
Entering of chemical substances into aquatic environment occurs either by involuntary accidents or discharging of chemical wastes resulting from tank washing operations of tankers carrying chemicals. MARPOL 73/78 Convention strict regulations on discharging of chemical residues left in their tanks to the sea, but permits the discharging of such residues provided certain conditions are met. In the present study; the period from 1996 to 2016 is examined and the number of new tankers participating in the chemical tanker fleet and the distribution of these tankers according to dwt tonnage is shown. The tanker fleet which consisted of 1.882 ships in 1966 reached 3.923 units in 2016. Accordingly, the volume of chemical merchandise carried by sea was 132 million tons in 1996, but it reached 287 million tons in 2016. According to the order books, it is understood that these figures will increase even more. The increase in the number of tankers and the growth of the capacities means that more chemical substances are transported at the same time and the tonnage of the chemical waste discharged to the sea is also on increase. Based on the scientific background which proves that chemicals cause biological accumulation and acute and chronic toxicity on aquatic life, and the results of chemical tanker development over the last 20 years that has been presented; It is necessary for maritime authorities to reconsider the legal arrangements for allowing chemical tankers to discharge chemical wastes from tank washing waters to the sea.  相似文献   

4.
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.  相似文献   

5.
Maritime transportation, the primary mode for intercontinental movement of crude oil, accounts for 1.7 billion tons annually – bulk of which are carried via a fleet of large crude oil tankers. Although spectacular episodes such as Exxon Valdez underline the significant risk and tremendous cost associated with marine shipments of hazardous materials, maritime literature has focused only on the cost-effective scheduling of these tankers. It is important that oil transport companies consider risk, since the insurance premiums is contingent on the expected claim. Hence through this work, we present a mixed-integer optimization program – with operating cost and transport risk objectives, which could be used to prepare routes and schedules for a heterogeneous fleet of crude oil tankers. The bi-objective model was tested on a number of problem instances of realistic size, which were further analyzed to conclude that the cheapest route may not necessarily yield the lowest insurance premiums, and that larger vessels should be used if risk is more important as it enables better exploitation of the risk structure.  相似文献   

6.
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.  相似文献   

7.
在格拉管线维持性技术改造中,对全线12座泵站的71座油罐进行了第二次防腐层除锈涂漆施工,积累了一些实践经验.对其施工要点进行了总结:查清旧油罐涂层的破损实情;落实除锈标准;彻底消除油罐渗漏隐患;选择适宜的施工条件;选择适合高原油罐防腐的涂料和适宜的涂刷方法;采取得力有效的安全措施.这些做法确保了高质量按期竣工,实现了安全无事故.这些实践经验,对类似工程有借鉴价值.  相似文献   

8.
Some scholars consider that today’s market conditions are in favor of the Northern Sea Route (NSR) rather than the Suez Canal Route (SCR). However, the number of bulk carriers using the NSR remains extremely limited, despite higher fuel prices since 2009 and subsequent significant fuel savings. In 2013, there were 53 transits via the Arctic, out of which 27 by oil tankers and 6 by bulk carriers. In this article we show that this result might be attributable to a factor, which is not considered in most studies: the spot freight rate to fuel ratio which governs ship owners’ decisions regarding the sailing speed. Due to a low ratio since 2011, the speed of vessels on the SCR is at its lowest level, and potential NSR fuel savings are too limited to provide a viable alternative. We further argue that, contrary to most studies, internalizing NSR environmental benefits marginally improves the attractiveness of the NSR.  相似文献   

9.
Abstract

Inland vessels move goods along waterways (canals and rivers) and they visit ports. Because of their tidal nature, vessels make use of locks to enter ports or waterways. From a port management point of view, fast access to and from the port and high utilization of locks are important objectives. Where the former relates to low inbound and outbound waiting times, the latter relates to the placement of as many vessels as possible in the lock before its operation. This article includes a case study that relates to the operation of the Van Cauwelaert lock in the port of Antwerp, Belgium. Lock operation policy is as follows: vessels wait in front of the lock for a port administrator to assign places in the lock based on knowledge of the vessels’ dimensions. As such, there is no FIFO-discipline, but a ‘group-FIFO’-discipline, i.e. if n vessels are allowed into the lock, they are the first n vessels in the arrival queue. A heuristic algorithm is formulated for the placement of vessels in the lock. This algorithm supports the decision where to place the vessel in the lock, aiming to place as many vessels as possible from the arrival queue. At the same time, it supports the decision to start a locking operation or not, based on information about vessels that are announced but which have not yet arrived at the lock's entrance. The heuristic is called a ‘less-flexibility-first’-heuristic as it looks for pseudo-placements, showing which flexibility is left for the remaining vessels after placing a vessel. This article describes the implementation of the heuristic and provides numerical examples. A comparison is made between the heuristic results and daily practice, based on real-life vessel movements through the Van Cauwelaert lock in 2002.  相似文献   

10.
This paper measures greenhouse gas emissions from port vessel operations by considering the case of Korea’s Port of Incheon. It provides estimates of greenhouse gas emissions based on the type and the movement of a vessel from the moment of its arrival, to its docking, cargo handling, and departure. Taking a bottom-up approach based on individual vessels’ characteristics and using data on vessels processed by the port in 2012 estimate emissions. The results indicate that the level of emissions is five times higher than that estimated through the top-down approach. Among various types of vessels, international car ferries are the heaviest emitters, followed by full container vessels and car carriers. A vessel’s passage through lock gates and maneuver to approach the dock accounts for 96% of its emissions. Docking for cargo handling shows the lowest level of GHG emissions.  相似文献   

11.
In this study we analyze the dmographic and geographical distribution of pedestrian accidents (n=28,452) in the Quebec Municipalités régionales de comté (MRC) reported between January 1, 1983 and December 31, 1988. In order to be able to make comparisons between MRCs, we have created in Comparative Mortality Index and a Comparative Morbidity Index. We use a logistic regression model to single out explanatory factors. The main tendencies which are apparent in the demographic analysis are an overrepresentation of young persons and elderly persons in the accident statistics, and that men are more at risk than women. Men 15 years and under and men 65 years and over are more at risk of being involved in a fatal pedestrian accident. The geographic analysis show that among men, the average mortality rate is one and a half times greater in rural MRCs than in urban MRCs; among women, rural mortality is two and a half times greater than urban mortality. In the case of non-severe injuries we note an over-representation of urban MRCs. Young persons 15 years or less who live in an urban, populated zone are those most at risk of being involved in a pedestrian accident. Identifying high risk groups or areas is a prerequisite step for injury prevention and control.  相似文献   

12.
This research applied the Green Flag Program to assess the benefits of reducing speed and fuel transfer for large merchant vessels (bulk and container) entering Kaohsiung Port. This study adopts an activity-based model to calculate fuel consumption and emissions, as well as setting up two scenarios, (1) decrease vessel speed to 12 knots 20 nm away from port; and (2) decrease vessel speed to 12 knots and transfer fuel 20 nm away from port, which based on the Green Flag Program in Long Beach, in the U.S. The findings are (1) In scenario one, the container and bulk vessels saw reductions in CO2 emissions of about 41% and 14%, respectively. In scenario two, container and bulk vessels had reductions of about 48% and 43% in SO2 emissions, respectively. (2) Large vessels are more environmentally friendly than small vessels. (3) Using the CATCH model to assess the effectiveness of the two scenarios, it was found that container vessels benefited from both reducing speed and fuel transfer, while bulk carriers only did so from the former.  相似文献   

13.
Abstract

Since 1990s the liner shipping industry has faced a period of restructuring and consolidation, and been confronted with a continuing increase in container vessel scale. The impact of these changes is noticeable in trade patterns, cargo handling methods and shipping routes, in short ‘operations’. After listing factors influencing size, growth in container ship size is explained by economies of scale in deploying larger vessels. In order to quantify economies of scale, this paper uses the liner service cash flow model. A novelty in the model is the inclusion of +6000-20-foot Equivalent Unit (TEU) vessels and the distinction in costs between single and twin propeller units on ships. The results illustrate that scale economies have been – and will continue to be – the driving force behind the deployment of larger container vessels. The paper then assesses the link between ship size and operations, given current discussions about the increase in container vessel scale. It is found that (a) ship size and operations are linked; (b) optimal ship size depends on transport segment (deep-sea vs. short-sea shipping, SSS), terminal type (transhipment terminals vs. other terminals), trade lane (East-West vs. North-South trades) and technology; and (c) a ship optimal for one trade can be suboptimal for another.  相似文献   

14.
Ever stricter emission regulations stimulate vessel owners to consider the adoption of alternative marine fuels, such as Liquefied Natural Gas (LNG). In deciding whether to invest in LNG-fueled vessels, initial investment and operating costs are decisive factors that have not yet been fully studied in the literature. In this paper, we present a new investment appraisal method to compare the costs of LNG-fueled vessels with conventional vessels. We analyze the fuel costs and overall exploitation costs by simulating bunker planning decisions under stochastic fuel prices, presence in emission controlled areas, and route lengths. Our analyses reveal that the fuel costs of LNG-fueled vessels are often lower than those of conventional vessels, even under unfavorable LNG prices. Due to the higher initial investment costs in LNG-fueled vessels, these fuel cost reductions do not always translate into lower overall exploitation costs. By conducting numerical experiments, we identified conditions under which the exploitation costs of LNG-fueled vessels are lower than conventional vessels.  相似文献   

15.
This paper assesses the pros and the cons of installing batteries on offshore support vessels. These vessels are specially designed to provide services to oil and gas operations, such as anchor handling, supply and subsea operations. They have multiple engines and advanced dynamic positioning systems to ensure that they can perform their duties with high reliability at nearly any sea state. Combined with high safety requirements, this has resulted in general operational patterns with vessels running multiple combustion engines even at calm water conditions. For emissions, low engine loads yield high emissions of exhaust gases such as nitrogen oxides (NOx) and aerosols such as black carbon (BC), due to less favorable combustion conditions. The high span for these vessels between low loads and high, and their great need for potential power at short notice, motivate our examination of hybrid setups with electric: the vessel segment should be more favorable than many. We find that combining batteries with combustion engines reduces local pollution and climate impact, while the economics with current battery cost and fuel prices is good enough for new vessels, but not good enough for retrofits.  相似文献   

16.
This paper describes the application of probabilistic risk assessment techniques to level crossing safety on JR East, the largest of the six private railroads in Japan. The risk of a level crossing accident was defined as the product of the accident rate and the expected consequences per accident. Rail traffic volume, road traffic volume, visibility of the crossing from the road, road gradient, width of the crossing and the type of safety devices at the crossing were shown to influence the accident rate and the collective risk. The mean accident rate at all crossings was 0.74 per million trains. The accident rate was 0.59 per million trains at crossings equipped with barriers, 1.25 at crossings equipped with warning bells and 0.76 at pedestrian crossings. Crossings equipped with obstacle detectors had a lower accident rate (0.12 per million trains) than crossings without detectors (0.43 per million trains). Crossings with visibility less than 20 m had a 50% higher mean accident rate than crossings with visibility greater than 20 m. As the number of tracks increased, the accident rate monotonically increased due to the increased accident exposure. Risk assessment techniques were applied to determine the efficacy of the various level crossing safety devices. In addition to upgrading the safety of crossings, the management techniques stressed the importance of education campaigns in warning the public about the dangers of illegal crossings.  相似文献   

17.
We solve the problem of tactical supply vessel planning arising in the upstream offshore petroleum logistics. Supply vessels deliver all the necessary materials and equipment to offshore installations from an onshore supply base according to a delivery schedule. The planning of supply vessels should be done so that their number is minimized and at the same time provide a reliable flow of supplies from the base. The execution of a weekly sailing plan is affected by weather conditions, especially in winter time. Harsh weather conditions increase the number of vessels required to perform the operations as well as the service times at the installations, and thus disrupt the schedule, leading to additional costs and reduced service level. We present a methodology for robust supply vessel planning enabling a trade-off analysis to be made between the schedules’ service level and vessels’ cost. The methodology involves the generation of multiple vessel schedules with different level of robustness using an adaptive large neighbourhood search metaheuristic and a subsequent discrete event simulation procedure for the assessment of the service level. To control the level of robustness we developed a concept of slacks and incorporated it into the metaheuristic algorithm.  相似文献   

18.
Summary

1) Western Europe has a navigable waterways‐network of about 19,000 kms. For the coming decades, however, about 40 percent of the length of these waterways has a very limited relevance, because of the small capacity of the barges that can pass along them.

2) Of the different types of barges the majority are the self‐propelled type. The importance of the pull‐towed barges is declining quickly, whereas the push‐towed barges are on the upswing.

3) The relative importance of inland shipping in comparison with rail transport is far from uniform. In The Netherlands inland shipping is dominant. On the other hand, in France, this mode of transport has only 30 percent of the total number of tons transported by inland shipping and railways together.

4) May the relative importance defer, there is a strong resemblance between the types of goods that are transported via the waterways with crude and manufactured minerals as well as building materials ranking high. In general, inland shipping is primarily involved in the transport of basic products and is of vital importance to the functioning of the West‐European economy.

5) The rather complicated legal regime of the waterways in Western Europe is certainly not the only reason why the integration in the transportation sector of the European Communities hardly moves on.

A fundamental discussion about the basic conceptions of the transport policy in the Common Market is unavoidable before real progress can be made. The entrance of the United Kingdom into the European Community may give an opening on this point.

6) Life goes on, with or without transport‐integration. Inland shipping moves forward too, paying for the use of infrastructure or not.

The general trends in transport support the expectation that the relative importance of inland shipping will increase in the coming decades. The increase in size of shipments and transport distances works in favour of this mode of transport. Besides this, inland shipping still has many possibilities to improve its productivity.

7) The future of inland shipping will be found in bulk transport and the transport of general cargo that has a volume per destination that goes far beyond the quantities for which the container or comparable types of transport units are better suited.  相似文献   

19.
Analysis of National Travel Survey data on the amount of walking done by 17,000 individuals has shown that people spend about twenty minutes per day travelling by foot, on average. This implies a pedestrian accident rate of about 500 accidents per hundred million miles walked, a greater rate than for car drivers but less than for motor cyclists. This paper also relates accident risk to age and sex of pedestrian, time of day, day of week, and month of year. It is further shown that, for daylight hours, the average number of pedestrian accidents is approximately proportional to the product of vehicle and pedestrian flows.The authors would like to thank the Department of the Environment and the Transport and Road Research Laboratory for making available NTS and accident data respectively, and C. E. Mollart for his able assistance.  相似文献   

20.
Intersection accidents represent a significant proportion of overall motor vehicle accidents. More accurate estimates of the actual effectiveness of intersection safety improvements are required. This study develops an improved methodology for post-implementation evaluation of safety countermeasures at intersections. Accidents are random, rarely occurring events. For a given time period, this leads to random fluctuations in accident frequencies, which suggests that statistical analysis employing confidence intervals, rather than point estimates, is required. Two technical problems complicate this treatment of accident occurrence as a random variable. The first problem is that identifying of hazardous locations is generally based on above-average accident frequency during the most recent period(s) for which data is available. The second problem arises from changes in external factors such as traffic volume, motor vehicle safety standards, etc., during the period of analysis, which may also affect traffic safety. A “combined” approach which addresses these technical issues is developed. Empirical Bayesian methodology is combined with regression techniques to derive a more accurate measure of the effect of safety treatments. An important consideration is the derivation of the variance of this measure, so that appropriate confidence intervals may be constructed. The approach is then applied to a sample of locations that underwent treatment by the Massachusetts Department of Public Works (MDPW). We compare our results to those which might be obtained using alternative methodologies that correct for neither or only one of the technical problems. We also illustrate how preliminary conclusions may be drawn regarding the effectiveness of broad categories of treatments, and how individual sites requiring further investigation may be identified.  相似文献   

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