Likelihood Of Accident Occurrence Research Articles

Trend of traffic on inland waterways of Port Harcourt urban coastal environment: a comparative safety imperative for a Ghanaian coastal regional province

The purpose of the study is to compare mobility and access in Sub- Saharan Africa urban cities of Nigeria and Ghana by analysing trends and accident probabilities on the inland waterways to improve safety standards. Primary data from100 respondents through structured data and interview from boat and ferry operators were used. The responses were ranked on a four-point scale based on the selected routes’ average accident probabilities in percent: Very Safe {0-20}, Fairy Safe {21- 50}, Unsafe {51- 80}, and Very Unsafe {81- 100}. Secondary data from the National Inland Waterways Authority (NIWA) and Ghana Maritime Authority (GMA) and the Volta Lake Transport Company (VLTC) were subjected to probability, percentage and trend analysis. Results indicate that in the Niger delta for every journey there is approximately 59% likelihood of fatal accident; while on the Volta Lake there is a likelihood of 7% fatal accident occurrence. The trend of traffic was high in the Niger delta noticeably in the routes of Akwa- Ibom. Cross Rivers and Rivers State. The Volta Lake recorded high traffic volumes on the routes of Yeji,Tapa Abo and Bidi on market days while on non-market days, Makango. Kwamekrom and Kpechu had high passenger volumes. Estimated annual passenger traffic on the Niger delta routes outweighed that on the Volta Lake routes on a ratio of 4:1. Safety analysis further reveals that the water ways of Port Harcourt in Rivers state were unsafe for travel while the water ways of the Volta Lake were relatively safe as revealed by the average probability ratio of 8:1 in comparative terms. The log linear regression analysis reveals a price elasticity of demand for boat transport of 1.00 and 0.97 for the selected route of Port Harcourt Nigeria and Volta Lake, Ghana respectively. It further supports the fact that more passengers were responsive to travel by waterways in Nigeria than Ghana. The study concludes that waterways of Niger delta basin have high risk indices and likelihood of accident occurrence than the Volta basin; and recommends that VLTC and NIWA should invest optimally and partner with the private sector to enforce and regulate the waterways operations so as to increase safety and mobility of users of the waterways.

SPA–fuzzy method based real-time risk assessment for major hazard installations storing flammable gas

For monitoring and control of major hazard installations storing flammable gas, the risk based warning/early-warning is very important. A set-pair analysis (SPA) based fuzzy assessment method (SPA–fuzzy) is proposed for the real-time risk assessment in this paper. Based on principle of SPA and fuzzy logic theory, the likelihood of accident occurrence and the consequence of the accident can be assessed, and the risk value or risk degree can be evaluated. The method takes advantage of the data acquired from the real-time safety monitoring system, so that the varying of the risk can be revealed during an accident developing. The risk assessment simulation of VCE accident caused by gas leaked from LPG tank is performed. It is shown that SPA–fuzzy method has the same risk value as that assessed by normal fuzzy method.

Modeling Accident Occurrence at Signalized Tee Intersections with Special Emphasis on Excess Zeros

In implementing effective remedial treatments at hazardous intersections, it often is necessary to identify the geometric and traffic factors that lead to accident occurrence. However, one particular problem frequently encountered in accident studies is how to distinguish virtually safe intersections with little likelihood of accident occurrence from those that have happened to have no accident due to the random process. To deal with this problem, the "excess" records of zero accident, the zero-inflated negative binomial was used to assign the probability to the accident outcome. Accident data at 104 signalized tee intersections in Singapore over a period of 9 years were employed for model development. The model indicates that uncontrolled left-turn slip road, permissive right-turn phase, existence of a horizontal curve, short sight distances, large number of signal phases, total approach volume, and left-turn volume may increase accident occurrence. On the other hand, right-turn channelization, acceleration section on the left-turn lane, median railings, and more than 5% approach gradient may reduce accident occurrence. Moreover, there is a trend of reducing accidents over the years.

ASSESSING ENVIRONMENTAL IMPACTS FROM A PUGET SOUND OIL SPILL

ABSTRACT An oil spill risk assessment determines the likelihood of accident occurrence and potential consequences of a spill when the spill occurs. An essential part of the risk assessment is an environmental impact assessment. The impact assessment identifies resources at risk and examines potential environmental contamination. Computer models can be used in conjunction with resource distributions to predict the impact of an oil spill. This paper provides an overview of the methodology used in assessing environmental impacts from an oil spill and examines various oil spill-modeling tools. The Regulatory Assessment: Use of Tug to Protect Against Oil Spills in the Puget Sound Area (USCG, 1999) includes a Qualitative Environmental Impact Assessment that serves as a case study demonstrating the environmental impact assessment process. The U.S. Coast Guard used this Regulatory Assessment to study the alternatives for improving maritime safety in the Puget Sound area. The following are elements and approaches adopted for the impact assessment:Problem formulation. Problem formulation is a planning and scoping process that establishes the goals, breadth, and focus of the risk analysis. A conceptual model is developed to identify environmental resources to be protected, data needed, and analysis to be used.Analysis. This analysis phase develops profiles of environmental exposure and effects of oil spills. The exposure profile characterizes the ecosystem that may be exposed and describes the magnitude and pattern of exposure.Validation. The validation process is a crucial step in defining the reliability of modeling environmental impacts. The use of several oil spill models can minimize the weakness and assumptions associated with each model. Actual spill incidents provide a range and magnitude of possible environmental damages, which further validate model results.