• Journal of Ocean Engineering and Technology
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• v.27 no.6
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• pp.43-55
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• 2013

In general, huge caissons for breakwaters have been constructed on land or a floating dock. In the case of the construction on a floating dock, a 4 step installation procedure is involved: i) construction on a floating dock, ii) transportation by the floating dock to an area near the target sea, iii) launching from the floating dock, and iv) transference by tug-boats to the installation site. It is especially important to pay attention to the dynamic stability of the floating dock against the conditions in the sea during steps i) and iii). In this paper, the static and dynamic stabilities of a caisson on a floating dock are evaluated based on IMO rules during the construction and launching of the caisson on a floating dock by using independent commercial S/Ws such as NAPA, WAMIT, and CHARM3D.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.628-634
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• 2012

Release of veterinary antibiotics (VSs) to agricultural environment through application of animal manure and/or animal manure-based composts to soils is of concern. The current study was conducted to examine decline of VAs during composting the chicken manure. For this, antibiotics free chicken manure (20 kg) and sawdust (10 kg) were added to the bench-scale composting apparatus and then the mixed material was spiked simultaneously with three VAs (chlortetracycline, CTC; sulfamethazine, SMZ; tylosin, TYL) at two different levels (10 and $20mg\;kg^{-1}$). Then the decline of VAs was determined using Charm II system during 53 composting period. For comparison, composting only chicken manure was included at VAs concentration of $10mg\;kg^{-1}$. During composting, the concentration of all three different VAs declined below the prospective guideline values ($0.8mg\;kg^{-1}$ for CTC, $0.2mg\;kg^{-1}$ for SMZ, and $1.0mg\;kg^{-1}$ for TYL) except CTC at $20mg\;kg^{-1}$ spiking when the chicken manure was composted together with sawdust. Interestingly, CTC at $10mg\;kg^{-1}$ spiking appeared to be declined under the guideline value without sawdust while SMZ was resistant to be declined without sawdust. Unlike CTC and SMZ, TYL showed immediate decline right after spiking TYL to composting materials regardless the spiking concentration and existence of sawdust. Appropriate composting procedure of chicken manure was able to decline the residual VAs in the manure below the prospective guideline value and the importance of organic substances on this decline was perceived.