The dissolution of CaCO(3) is one of the ways ocean acidification can, potentially, greatly affect the ballast of aggregates. A diminution of the ballast could reduce the settling speed of aggregates, resulting in a change in the carbon flux to the deep sea. This would mean lower amounts of more refractory organic matter reaching the ocean floor. This work aimed to determine the effect of ocean...

POWER ENGINEERING JOURNAL APRIL 2002 61 I nduction generators are commonly used for small hydro schemes due to advantages such as availability, low cost and robustness. The cost per kW of a single-phase generator is generally higher than a threephase generator. Hence a three-phase generator, which produces a single-phase output, is normally used. In order to minimise further the capital cost, c...

This paper proposes fluorescent electronic ballast with high power factor and low line input current harmonics. The system performance can be improved by a charged pump circuit. Details of design and circuit operation are described. The proposed electronic ballast is modified from single stage half bridge class D electronic ballast by adding capacitor parallel with each power switch and setting...

In the recent years many authors [1-4] are working to obtain single stage HPF electronic ballast for fluorescent and HID lamps to obtain cost reduction and to comply with international standard requirements. Usually to obtain HPF in electronic ballast for high pressure sodium lamps a Power Factor Preregulator (PFP) is used between the mains and the electronic ballast [5]. In this paper will be ...

This paper presents the design and develops of voltage acceptability curves for LED lamps. It is done with the mathematical representation of DC bus voltage of LED lamps internal ballast circuit during voltage sags. First, experimental analysis was done to determine the effect of voltage sag of LED lamp. From the findings on the variation of DC bus voltage during voltage sag, a mathematical equ...

Currently, seawater flushing is the only management strategy for reducing the number of viable organisms in residual sediments and water of ballast tanks of vessels declaring no ballast on board (NOBOB) that traffic ports of the eastern United States. Previously, we identified several species of freshwater and brackish-water peracarid crustaceans able to survive the osmotic shock that occurs du...

Indicator organisms and antibiotic resistance were used as a proxy to measure microbial water quality of ballast tanks of ships, and surface waters in a tropical harbor. The survival of marine bacteria in ballast tanks appeared to diminish over longer water retention time, with a reduction of cell viability observed after a week based on heterotrophic plate counts. Pyrosequencing of 16S rRNA ge...

Korea Train eXpress (KTX) is now being operated, which allows Korea being one of the countries that operates the high-speed rail system. The high-speed rail has its advantage of short time transportation of population and materials, which lead to many researches performed in this matter. In the case of high speed classical trackbed system, the maintenance and usability of gravel ballast system ...

The determination of the strategy to ensure that the geometry for railway track is kept within acceptable limits, in a cost effective manner, is a complex process. It requires the simultaneous consideration of the activities which govern inspection, maintenance and renewal. In addition to this the geometry degradation process is dependent upon the maintenance history. The condition where the tr...

Ship ballast water treatment methods face many technical challenges. The effectiveness of every treatment method usually is evaluated by using large scale equipment and a large volume of samples, which involves time-consuming, laborious, and complex operations. This paper reports the development of a novel, simple and fast platform of methodology in evaluating the efficiency and the best parame...