Abstract: The potential benefits of LNG as fuel with regard to technical adaptability, compliance with emission regulations and reduced operating costs in ships have attracted the attention of stakeholders in the marine industry, and have recently experienced a significant rise in ship applications.  Statistically, it was found that the most dominant types of LNG fuelled ships are passenger/car ferries, followed by supply vessels and tugs operating within the coastal domain of inland waterways. A statistical survey of the raw data of the recent passenger-car ferries powered by LNG fuel was carried out, wherein the data of approximately 40 vessels was gathered from reliable sources. The data was tabulated, analyzed and plotted to demonstrate the different relationships between the main ship dimensions and other essential ship parameters.  This data takes the form of charts and formulae for determining the length of a new ship in relation to other ship particulars such as the breadth, depth, draft, speed and engine power.  Similar charts and formulae were plotted and created for determining the relationship and trends between the dead weights and breadth, depth and draft of the same type of ships.  Further, charts and formulae were designed depicting the relation between the LNG fuel tank volume and the tank diameter, the relation between tank volume and tank length, the relation between tank volume and tank weight in empty and full conditions, and the relation between tank volume and the total installed power. A chart illustrates the relation between the natural gas consumption and the ship installed power. The overall outcome of the plotted charts and given formulae can serve as trend guidance in the preliminary design phase for passenger/car ferries.

Abstract: In response to critical ship emission issues, the known devastating impact and strict national and international emission regulations, several options for emission reduction were investigated.In order to achieve the emission reduction goal, a set of practices can be adopted separately or in combination, including but not limited to alternative fuels, energy saving strategies and tools, renewable energy and abatement technology. In this paper, motivational factors, historical background, project development, locations, supply and demand, and reserve quantities of marine fuels are addressed. Potential scenarios involving alternative fuel drivers and emission reduction solution options are discussed. The alternative fuels addressed here include a comparison of their weighting aspects. Further, emission reduction abatement technology is explored. Among the current available alternative fuels (ethanol, methanol, bio-fuel, hydrogen, propane and natural gas), LNG is collectively the best fuel alternative due to measured superiority as the cleanest environmentally, the reasonable cost, suitability for propulsion engines and many other merits. 

Abstract: This paper deals with development of regression models for prediction of compressive strength of bagasse ash (BA) concrete. The compressive strength of dry BA concrete was determined using two variables, namely, curing period and pozzolanic Portland cement (PPC) content for BA grain size < 0.075 and water – PPC ratio of 0.55. The polynomial regression models were developed by varying PPC replacements (0, 5, 10, 15, 20, 25 and 30 percent) and curing periods (7, 14 and 28 days). Effort was made to modify the polynomial models using a three step approach. First step was identifying the best curve fitting technique (least square and interpolation methods). The second step of model development was to compute adjusted R2 for the polynomial Regression models. The final step was model validation. Least square quadratic polynomial (LSQP) with degree of the regression n = 4 was established as the most effective and accurate model in compressive strength prediction of BA concrete.