• Computers and Concrete
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• v.15 no.4
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• pp.589-606
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• 2015

It is well-documented that the major deterioration of coastal RC structures is chloride-induced corrosion. Therefore, regional investigations are necessary for durability based design and evaluation of the proposed service life prdiction models. In this paper, four reinforced concrete jetties exposed to severe marine environment were monitored to assess the long term chloride penetration at 6 months to 96 months. Also, some accelerated durability tests were performed on standard samples in laboratory. As a result, two time-dependent equations are proposed for basic parameters of chloride diffusion into concrete and then the corrosion initiation time is estimated by a developed probabilistic service life model Also, two famous service life prediction models are compared using chloride profiles obtained from structures after about 40 years in the tidal exposure conditions. The results confirm that the influence of concrete quality on diffusion coefficients is related to the concrete pore structure and the time dependence is due to chemical reactions of sea water ions with hydration products which lead a reduction in pore structure. Also, proper attention to the durability properties of concrete may extend the service life of marine structures greater than fifty years, even in harsh environments.

• Ocean Systems Engineering
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• v.2 no.3
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• pp.229-238
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• 2012

We discuss the bi - stability that is possibly exhibited by a liquid free surface in a parametrically - driven two-dimensional (2D) rectangular tank with finite liquid depth. Following the method of adaptive mode ordering, assuming two dominant modes and retaining polynomial nonlinearities up to third-order, a nonlinear finite-dimensional nonlinear modal system approximation is obtained. A "continuation method" of nonlinear dynamics is then used in order to elicit efficiently the instability boundary in parameters' space and to predict how steady surface elevation changes as the frequency and/or the amplitude of excitation are varied. Results are compared against those of the linear version of the system (that is a Mathieu-type model) and furthermore, against an intermediate model also derived with formal mode ordering, that is based on a second - order ordinary differential equation having nonlinearities due to products of elevation with elevation velocity or acceleration. The investigation verifies that, in parameters space, there must be a region, inside the quiescent region, where liquid surface instability is exhibited. There, behaviour depends on initial conditions and a wave form would be realised only if the free surface was substantially disturbed initially.

• Journal of Fisheries and Marine Sciences Education
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• v.5 no.2
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• pp.80-89
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• 1993

Notwithstanding Korea and P. R.China are located in the neighborhood each other geographically, the break of diplomatic relations of them continued a long term, and the difference of ideology and social structure of two countries was acting as a barrier to understand each other in many fields. Two countries established formal diplomatic relation in 1992, and then the interchange and mutual cooperation between both countries are being performed rapidly, but the field of fisheries education and research system is continuing in the early stage yet. It can be easily expected that the interchange and mutual cooperation in the field of fisheries through the ocean contribute not only to the international friendship, but to the rational management of fisheries resources. In accordence with the necessity mentioned above, the author considered the general situation of fisheries education and research system in P. R. China. P. R. China runs two kinds of fisheries education system which are regular and irregular system. The regular education system is the principal means of cultivating fisheries scientists and technicians. And there are three grade levels in regular education : the tasks of which are undertaken by the fisheries universities, fisheries colleges and fisheries high schools. Adult education system in fisheries are of the following types : fishery cadet training courses, evening schools, correspondence courses and broadcasting or TV programs. The fisheries research in P. R. China is undertaken by the research institutes under the Bureau of Aquatic Products, and the basic research of oceanography is undertaken by the oceanographic institutes under the Chinese Academy of Science.

• Asia pacific journal of information systems
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• v.1 no.1
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• pp.147-163
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• 1991

The insurance industry is highly competitive since it is difficult to differentiate one company's service from another. This paper examines how Ankuk Fire & Marine Insurance has differentiated its service and improved its competitive edge against others by using electronic data interchange (EDI). In order to improve its service level, Ankuk Fire Insurance has significantly reduced paper work by transmitting information electronically to its customers. This was possible with standardized product codes and databases which were installed both on the Ankuk and customer premises. Ankuk Fire Insurance transmits its customer's insurance information to the customer's database instead of hand-carrying or mailing it. The main benefits of this has been: (1) fewer errors as data does not need to be re-entered, (2) faster customer service with electronic data delivery, and (3) better quality customer service due to highly structured relationships with customers. EDI will soon be available to all insurance companies due to the goverment's aggressive promotion of a KTNet plan. Ankuk Insurance, therefore, needs to adopt the standardized protocol recommended by KTNet and develop new products which will give them a competitive edge and minimize the possibilities of losing their clients to other insurance firms.

• Journal of Surface Science and Engineering
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• v.51 no.4
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• pp.218-223
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• 2018

In this study, we proposed a new ultrasonic-chemical decontamination process for decontaminating radioactive corrosion products during the maintenance of reactor coolant pump (RCP). The actual decontamination process was reproduced in the laboratory. And the corrosion characteristics of stainless steel (STS), constituting the RCP interior parts, were examined. The weight-loss measurment and polarization experiment were carried out in order to determine the corrosion characteristics of STS 304 and STS 415 by repeated decontamination processes. The STS 304 presented a little corrosion damage, which was almost indistinguishable from visual observation. The weight-loss rate of STS 304 was also significantly lower. On the other hand, STS 415 showed severe corrosion damage on its surface, greater weight-loss rate and higher corrosion current density than STS 304.

• Journal of Fisheries and Marine Sciences Education
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• v.16 no.2
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• pp.210-217
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• 2004

Cooling technology has been a vital prerequisite for the rapid, if not explosive, growth of the electronic equipment industry. This has been especially true during the last 20 years with the advent of intergrated circuit chips and their applications in computers and related electronic products. The purpose of this study is to develop a telecommunication equipment cooling system using a thermoelectric module combined with cooling fan. Thermoelectric module is a device that can perform cooling only by input of electric power. In the present study, the cooling package using the thermoeletric module has been developed to improve the thermal performance. The cooling characteristics of the electronic chip was placed into the subrack and it can be rapidly assembled or disassembled in the equipment rack. As a preliminary experiment, the cooling performances between a conventional way using a cooling fin and a proposed method applying the thermoelectric module was comosed and analyzyed. The cooling performance at a simulated electronic component packaging a thermomodule operated well.

• Corrosion Science and Technology
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• v.20 no.6
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• pp.403-411
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• 2021

In this study, the reliability of a commercial ER-type corrosion sensor was evaluated under an accelerated corrosion environment to verify its suitability for application in monitoring of ship's seawater piping system. A closed-loop pump piping testbed was designed and constructed to compare the wall thickness reduction of the pipe and the response from the sensor. The sensor was attached inside the pipe near the outlet of the pump that was exposed to a 3.5% NaCl solution with or without copper accelerated acetic acid (CASS). The results demonstrated that the presence of CASS significantly increased the corrosivity of the solution as well as the thickness reduction of the pipe, as expected. On the other hand, the corrosion products formed by the solution with CASS were thicker compared with those without CASS. The sensor response to temperature variation was found to be a clear linear relationship for the solution without CASS but there was a non-linear relationship where CASS was present.

• The Journal of Economics, Marketing and Management
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• v.6 no.4
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• pp.41-49
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• 2018

Purpose - The purpose of the study was to investigate restaurants increasing seaweed of marine products and to let consumers live healthy and happy lives and to discuss increase of seaweeds consumption. The purpose of the study was to give consumers good food and to live healthy and happy life and to elevate life quality and to produce added value by increase of consumption of seaweeds such as laver, brown seaweed, tangle and gracilaria and others and to give economic advantage. The seaweed could be produced in large quantity without spending of much money in accordance with demand to make use of it at restaurants. Research design, data, and Methodology - The author visited restaurant businessmen at Suwon, Anyang, Hwaseong and Yongin to investigate low sales by in-depth interview. The study investigated Kodari-jorim restaurants that made use of laver ssam for side dish. The subject was HS distributors to let restaurant keepers think of seaweeds and replacement of vegetable by seaweed. Results - Women customers who thought of health and diet usually selected menu at the restaurants not to appeal. Conclusions - Menu with high quality seaweeds (low calory, satiety and health) can satisfy women customers thinking much of health and diet to increase consumption of seaweeds. The study was exploratory to investigate in qualitative and quantitative way in the future.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.701-708
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• 1996

To evaluate the possibility of using a by-products of skipjack canning as a food or feedstuff, the proximate composition, total and free amino acids, total lipid composition, and nucleotide related compounds were analyzed. The crude protein was highest in dark muscle, while lipid was highest in head. The important total amino acids in by-products were founded to be glycine, glutamic acid, alanine and histidine. The important free amino acids from dark muscle and head were taurine, histidine and anserine. The amounts of histidine, anserine and carnosine in dark muscle was higher than those of cooking drips, head, and raw vicera. The major fatty acids in by-products were palmitic, stearic, oleic and docosahexaenoic acid (DHA). The inosine and hypoxanthine were important nucleotide related compounds in by-products. The results suggests that by-products from skipjack can be used as food sources and feedstuffs especially for marine fish culture.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.288-294
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• 2014

Penicillin and its salts, including the benzatine, procaine, and sodium salts, have been widely used in human and veterinary medicine. Owing to their low toxicity, they currently form the most important group of antibiotics. However, overdose and abuse of these antibiotics may lead to potential risk in human health. Therefore, this study was conducted to validate the analysis method established by the Korea Food Code in 2012 and to monitor the levels of benzylpenicillin residues in products with reference to the maximum residue level (MRL). Of the 232 product samples tested, benzylpenicillin was detected in 11 livestock products and 2 marine products. Benzylpenicillin concentrations were found to be lower than the MRL in 12 products; however, the concentration of benzylpenicillin was found to be greater than the MRL in 1 pork product. The limit of quantification (LOQ) for benzylpenicillin was found to be 0.001-0.002 mg/kg, with an average recovery of 90.4-115.3%. Calibrations showed good linearity of 0.995 over a range of 0.002-0.05 mg/kg.