scholarly journals Influence of pitting corrosion on fatigue and corrosion fatigue of ship structures Part I Pitting corrosion of ship structures

2013 ◽  
Vol 21 (1) ◽  
pp. 62-69 ◽  
Author(s):  
Marek Jakubowski
Keyword(s):  
Growth Rate ◽  
Marine Environment ◽  
Pitting Corrosion ◽  
Nucleation And Growth ◽  
Literature Survey ◽  
Growth Phases ◽  
Specific Kind ◽  
Ship Structures ◽  
Pit Nucleation

ABSTRACT The present paper is a literature survey focused on a specific kind of corrosion, i.e. pitting corrosion and its influence on fatigue of ship and offshore steels. Mechanisms of a shortand long-term pitting corrosion in marine environment have been described including pit nucleation and growth phases. Some models of pit growth versus time of exposure have been presented. Some factors which influence the pit growth rate have been discussed briefly

Pitting Degradation Modeling of Ocean Steel Structures Using Bayesian Network

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Jyoti Bhandari ◽  
Faisal Khan ◽  
Rouzbeh Abbassi ◽  
Vikram Garaniya ◽  
Roberto Ojeda
Keyword(s):  
Bayesian Network ◽  
Structural Steel ◽  
Marine Environment ◽  
Pitting Corrosion ◽  
Steel Structures ◽  
Poor Quality ◽  
Real World Data ◽  
Corrosion Depth ◽  
Operational Conditions

Modeling depth of long-term pitting corrosion is of interest for engineers in predicting the structural longevity of ocean infrastructures. Conventional models demonstrate poor quality in predicting the long-term pitting corrosion depth. Recently developed phenomenological models provide a strong understanding of the pitting process; however, they have limited engineering applications. In this study, a novel probabilistic model is developed for predicting the long-term pitting corrosion depth of steel structures in marine environment using Bayesian network (BN). The proposed BN model combines an understanding of corrosion phenomenological model and empirical model calibrated using real-world data. A case study, which exemplifies the application of methodology to predict the pit depth of structural steel in long-term marine environment, is presented. The result shows that the proposed methodology succeeds in predicting the time-dependent, long-term anaerobic pitting corrosion depth of structural steel in different environmental and operational conditions.

scholarly journals The study of long-term durability and bio-colonization of concrete in marine environment

2021 ◽  
pp. 100120
Author(s):  
Marine Georges ◽  
Amel Bourguiba ◽  
Daniel Chateigner ◽  
Nassim Sebaibi ◽  
Mohamed Boutouil
Keyword(s):  
Marine Environment

Marine Environmental Damage: The Compensability of Ecosystem Service Loss in International Law

2019 ◽  
Vol 34 (4) ◽  
pp. 602-641
Author(s):  
Günther Handl
Keyword(s):  
International Law ◽  
Marine Environment ◽  
Oil Pollution ◽  
Environmental Damage ◽  
Emerging Trends ◽  
Full Compensation ◽  
Environmental Loss ◽  
National Practice ◽  
Marine Environmental

AbstractKey maritime conventions governing liability and compensation for pollution of the marine environment, foremost among them the 1992 Civil Liability for Oil Pollution Convention and the 2003 Supplementary Fund Protocol (the CLC/Fund regime), exclude compensation for pure environmental loss. This article discusses whether anything less than full compensation of damage to the marine environment, including the loss of ecosystem services, comports with contemporary international public policy or law. After reviewing and rejecting traditional arguments opposing such compensability, the article contrasts the CLC/Fund regime’s environmental claims practice with emerging trends in decision on the international legal plane and in select domestic legal systems, all of which support full compensation. The article thus concludes that an adjustment of the CLC/Fund regime’s environmental claims approach is desirable to align it with this international (and national) practice and thereby to protect the long-term integrity of the regime itself.

Phase separation in undercooled molten Pd80Si20: Part I

1999 ◽  
Vol 14 (9) ◽  
pp. 3653-3662 ◽  
Author(s):  
K. L. Lee ◽  
H. W. Kui
Keyword(s):  
Growth Rate ◽  
Phase Separation ◽  
Crystal Growth ◽  
Grain Refinement ◽  
Crystallization Temperature ◽  
Sharp Decrease ◽  
Nucleation And Growth ◽  
Crystal Growth Rate ◽  
Large Undercooling ◽  
Kinetic Crystallization

Three different kinds of morphology are found in undercooled Pd80Si20, and they dominate at different undercooling regimens ΔT, defined as ΔT = T1 – Tk, where T1 is the liquidus of Pd80Si20 and Tk is the kinetic crystallization temperature. In the small undercooling regimen, i.e., for ΔT ≤ 190 K, the microstructures are typically dendritic precipitation with a eutecticlike background. In the intermediate undercooling regimen, i.e., for 190 ≤ ΔT ≤ 220 K, spherical morphologies, which arise from nucleation and growth, are identified. In addition, Pd particles are found throughout an entire undercooled specimen. In the large undercooling regimen, i.e., for ΔT ≥ 220 K, a connected structure composed of two subnetworks is found. A sharp decrease in the dimension of the microstructures occurs from the intermediate to the large undercooling regimen. Although the crystalline phases in the intermediate and the large undercooling regimens are the same, the crystal growth rate is too slow to bring about the occurrence of grain refinement. Combining the morphologies observed in the three undercooling regimens and their crystallization behaviors, we conclude that phase separation takes place in undercooled molten Pd80Si20.

scholarly journals Long-term Performance of Concrete under Marine Environment

2001 ◽  
Vol 39 (10) ◽  
pp. 17-24
Author(s):  
H. Hamada ◽  
T.U. Mohammed ◽  
T. Yamaji ◽  
H. Watanabe
Keyword(s):  
Marine Environment ◽  
Long Term Performance ◽  
Term Performance

ON THE CONSUMPTION/DISTRIBUTION THEOREM UNDER THE LONG-RUN GROWTH CRITERION SUBJECT TO A DRAWDOWN CONSTRAINT

2010 ◽  
Vol 13 (06) ◽  
pp. 931-957 ◽  
Author(s):  
MICHAEL J. KLASS ◽  
KRZYSZTOF NOWICKI
Keyword(s):  
Growth Rate ◽  
Short Term ◽  
Long Run ◽  
Time Period ◽  
Total Capital ◽  
Growth Criterion ◽  
Drawdown Constraint ◽  
Riskless Asset ◽  
Distribution Theorem

Consider any discrete time sequence of investment fortunes Fn which has a finite long-run growth rate [Formula: see text] when subject to the present value capital drawdown constraint Fne-rn ≥ λ* max 0≤k≤nFke-rk, where 0 ≤ λ* < 1, in the presence of a riskless asset affording a return of er dollars per time period per dollar invested. We show that money can be withdrawn for consumption from the invested capital without either reducing the long-run growth rate of such capital or violating the drawdown constraint for our capital sequence, while simultaneously increasing the amount of capital withdrawn for consumption at the identical long-term rate of V(r, λ*). We extend this result to an exponentially increasing number of consumption categories and discuss how additional yearly contributions can temporarily augment the total capital under management. In addition, we assess the short-term practicality of creating such an endowment/consumption/distribution program.

The Effects of Reduced Salinity on the Shell Growth of Small Mytilus Edulis

1984 ◽  
Vol 64 (1) ◽  
pp. 171-182 ◽  
Author(s):  
Patricia C. Almada-Villela
Keyword(s):  
Growth Rate ◽  
Mytilus Edulis ◽  
High Salinity ◽  
Shell Growth ◽  
Experimental Period ◽  
Gradual Decline ◽  
Poor Growth ◽  
Term Response ◽  
Better Than

The shell growth of small coastal Mytilus edulis L. was measured at three different constant low salinities over short periods of time. Growth was significantly depressed in 6·4 and 16‰ S but not in 22·4‰ S. Fluctuating salinities between 0 and 32‰ S depressed growth whether the fluctuations were of sinusoidal or abrupt form. After 1 week of preconditioning to constant 32‰ S the growth of coastal (Bangor) mussels was better than estuarine (Conwy) mussels. However, after two weeks’ preconditioning to 32‰ S the estuarine mussels displayed the best growth. In the fluctuating regime, both coastal and estuarine mussels exhibited poor growth rates. The long-term response of the shell growth of coastal M. edulis was followed over a period of 44 days. Salinities in the range 1·8–9·6‰ S were lethal to the mussels within 10 days. In 12·8 and 16‰ S growth was initially delayed but recovered eventually. There was a gradual decline in the growth rate of the mussels exposed to the higher salinities (19·2–32‰) and an improvement in the growth of the mussels living in lower salinities (12·8 and 16‰) to levels nearly matching that of the high salinity animals by day 37. This suggests that acclimation of the shell growth of M. edulis to salinities in the 12·8–28·8‰ S range was achieved by the mussels during the experimental period.

Walleye (Stizostedion vitreum vitreum) and Yellow Perch (Perca flavescens) Populations and Fisheries of the Red Lakes, Minnesota, 1930–75

1977 ◽  
Vol 34 (10) ◽  
pp. 1774-1783 ◽  
Author(s):  
Lloyd L. Smith Jr.
Keyword(s):  
Growth Rate ◽  
Yellow Perch ◽  
Climatic Factors ◽  
Perca Flavescens ◽  
Growing Season ◽  
Commercial Fishery ◽  
Class Strength ◽  
Parent Stock ◽  
Catch Statistics

In an investigation of the commercial fishery of Red Lakes, Minnesota, for the 46-yr period 1930–75, catch statistics were analyzed, and the dynamics of the perch and walleye populations were examined. Mean annual yields of walleye for two statistical periods, 1930–53 and 1954–75, were 309,900 and 245,100 kg, respectively for walleyes, and 96,400 and 109,500 kg for perch. Annual abundance (CPE based on average catches per day per 5-net units of gill nets) varied from 3.8 to 64.6 kg for walleye, and from 2.5 to 34.4 kg for perch. Causes of fluctuations in harvestable stock were directly related to strength of year-classes and to growth rate during the season of capture. Year-class strength was not related to the abundance of parent stock or of potential predators. The respective strengths of year-classes of perch and walleye in the same year were positively correlated (r = 0.859, P < 0.01), and are directly related to climatic factors. Growth rate of walleye in different calendar years varied from +30.7 to −42.2% of mean growth, and that of perch from +13.4 to −8.6% (1941–56). Growing season began in mid-June and was almost over by September 1. Walleye yield could be enhanced by starting harvest July 1 instead of early June. Perch yield could be improved by harvesting small perch. Key words: Percidae, Perca, population dynamics, Stizostedion, long-term yield

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