• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.5
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• pp.276-281
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• 2007

The toxicity of two species of puffer fish, Takifugu xanthopterus and T. stictonotus, collected from coastal regions of Korea, was determined using a mouse bioassay. The highest toxin scores in the muscle, skin, fins, and testis in both species were below 50 mouse units (MU) per gram, and for each organ of both species the proportion of toxic specimens containing ${\geq}10MU/g$ was less than about 10%. In T. xanthopterus, the highest toxin levels in the liver, gallbladder, and ovary exceeded 1,000 MU/g (1,275-1,910), while less than 200 MU/g (12-136) was detected in the same organs of T. stictonotus. Therefore, the toxicities of muscle, skin, and testis in both species of puffer fish were within acceptable levels for human consumption.

• Journal of Electrical Engineering and Technology
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• v.13 no.5
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• pp.1852-1863
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• 2018

Direct current(DC) systems have recently attracted attention due to the increase in DC loads and distributed generations, such as renewable energy sources. Among these technologies, there has been much research into DC distribution systems or DC microgrids. Within this body of research, the main topics have been about optimum control and operation methods in terms of improving power efficiency. When DC systems are controlled and operated using power electronic devices such as converters, it is necessary to design and analyze them by considering the power electronics sections. For this reason, we propose a scalable DC system analysis algorithm, which considers various system configurations depending on the operating mode and location of the converter. The algorithm consists of power flow fault current calculations, and the results of the algorithm can be used for designing DC systems. The algorithm is implemented using MATLAB with defined input and output data. The verification of the algorithm is mainly performed using ETAP software, and the accuracy of the algorithm analysis can be confirmed through the results.

• Fisheries and Aquatic Sciences
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• v.21 no.12
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• pp.36.1-36.11
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• 2018

Background: To confirm whether shellfish are suitable for consumption, the quality of seawater and shellfish in shellfish-producing areas must be assessed regularly. This study was conducted to evaluate the bacterial quality on the Changseon area, containing a designated shellfish-producing area, in Korea during 2011-2013. Result: Even though many inland pollutants near the area were identified, they showed no significant impact on the designated area and the shellfish therein. The concentrations of fecal bacteria in all the seawater and mussel samples from the designated area during the harvesting season were within the standards of various countries. Pathogenic bacteria were not detected in any of the mussel samples. In our previous study, the hazardous metal levels in all the mussels from the same area were also within the limits of different countries. Conclusion: The mussel products in this area are suitable for consumption based on fecal pollution, pathogenic bacteria, and also heavy metals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.1
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• pp.15-19
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• 2009

A simple and sensitive method for erythromycin quantification by liquid chromatography electrospray mass spectrometry (LC-MS/MS) in fishery products was developed. Samples were extracted by liquid-liquid extraction using 70% acetonitrile. Lipids were removed by acetonitrile saturated hexane. LC separation was performed on a Shiseido UG C-18 column ($150\;mm{\times}2.0\;mm$ internal diameter.) with a gradient system of 0.2% acetic acid-acetonitrile containing 0.2% acetic acid as a mobile phase at flow rate of 0.2 mL/min. The mass spectrometer was operated in selected reaction monitoring with positive electro-spray interface. Transitions were monitored a m/z $734{\to}577$ and $734{\to}158$, with m/z $734{\to}577$ chosen for quantification. Recovery of erythromycin from fish and shrimp fortified at the 10 ng/mL, 50 ng/mL and 100 ng/mL were 91.6-109.4%, 84.4-111.2% and 98.8-109.6% with high precision, respectively. Limits of quantification and limits of detection of erythromycin in both fish and shrimp were 10.0 ng/mL and 1.0 ng/mL, respectively. This analysis method for erythromycin has been proposed for registration in the Korean Official Methods of Food Analysis and has been utilized for fishery products analysis by the Korea Food and Drug Adminstration and the National Fisheries Products Quality Inspection Service.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.5
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• pp.1404-1409
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• 2004

Cheonmabanhwa-Tang(CBT) has been used in the Oriental Medicine for many centuries as a therapeutic agent for dizziness due to Poong-Dam. This Study was designed to investigate the mechanism of Prescription on cerebral hemodynamics [regional cerebral blood flow(rCBF) and pial arterial diameter(PAD)J in cerebral ischemia rats, The results in cerebral ischemic rats were as follows: Both rCBF and PAD were significantly and stably increased by CBT (10 ㎎/㎏, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. Pretreatment with indomethacin(1 ㎎/㎏, i.p.), an inhibitor of cyclooxygenase significantly but unstably increased the CBT-induced increases in PAD as well as rCBF during the period of cerebral reperfusion. Pretreatment with methylene blue(10 (.1.㎍/㎏, i.p.), an inhibitor of guanylate cyclase significantly but unstably increased the CBT-induced increases in PAD as well as rCBF during 150 minutes of cerebral reperfusion, but decreased stably the CBT-induced increases in rCBF and PAD after 180 minutes of cerebral reperfusion. In conclusion, the present authors thought that CBT caused effect on cerebral hemodynamics via mediation of cyclooxygenase.

• Journal of Biosystems Engineering
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• v.7 no.2
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• pp.36-44
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• 1983

Farm population was rapidly decreasing due to shift of the people from farm sector to the non-farm sector caused by the economic growth of the country. Especially, a great shortage of farm labor in busy farming period in June and October is becoming a serious problem in maintaining or promoting land productivity. The peak of labor requirement in summer is caused by rice transplanting and barley harvesting. In order to reduce the restrictions imposed on farm management by the concurrence of labor requirement and the lack of labor, the experimental study for mechanization of barley harvesting has been carried out in the fields. 1. The machines for barley harvesting were knap-sack type reapers, windrow reaper (power tiller attachment), binder and combine. The order of higher efficiency of machine for barley harvesting was combine, binder, windrow reaper (WR), knapsack type reaper 1(KSTR1), and knap sack type reaper 2(KSTR2; mist and duster attachment). 2. The ratio of grain loss for the manual, binder, and combine plot was about four percent of total field yield. 3. The total yield of barley in 35 days and 40 days harvesting after heading were 514 kg and 507kg per 10 ares respectively. The yield of 35 days-plot was higher than other experimental plots. 4. The lowest yield was recorded in 30 days-plot due to the large quantity of immatured grains and having lighter 1000-grain weight. The ratio of immatured grains was 2.66 percent and 1000-grain weight was 29.4 grams. 5. The total harvesting cost of the windrow reaper was 10,178 won per 10 ares. It was the lowest value compared to other machines. The next were combine, binder, KSTR1, KSTR2, and manual in sequence. As a result, the optimum time of barley harvesting for mechanization was 35-40 days after heading. Combine, binder, and windrow reaper were recommended as the suitable machines for barley harvesting in the work efficiency. However, in total harvesting cost, the windrow reaper was the most promising machine for barley harvesting.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.1
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• pp.12-17
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• 2010

Wild and cultured fish including olive flounder, sea bass, rock bream, yellowtail, gray mullet, gizzard shad, black rockfish, red seabream and squid were collected from a fish market located on the coast of Korea, and the antibiotic content of their muscle was investigated. Tetracycline group antibiotics were not detected in the 108 individuals of 9 species of wild fish. However, oxytetracycline (OTC) and tetracycline(TC) were detected in some samples of the 111 individuals in 7 cultured live fish species. The detected ranges of OTC and TC were ND~ 0.06 and ND~ 0.03, respectively. Five different fluoroquinolone antibiotics were also tested for, but were not detected in the wild fish species. Only small amount of criprofloxacin(ND~0.029 mg/kg) were detected in a few cultured fish samples. Oxolinic acid was not detected in either wild and cultured fish samples. Results showed that even very low levels of antibiotics could be detected by the testing methods used. Antibiotics were identified in a few fish samples but levels were far below the maximum allowable limits of the Korean Food Code, and the safety of fish being sold in markets, with regard to antibiotic levels, was confirmed.

• Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.17.1-17.9
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• 2016

The seasonal variation of fecal coliforms (FCs) and physicochemical factors was determined in seawaters of the Hansan-Geojeman area, including a designated area for oyster, and in inland pollution sources of its drainage basin. The mean daily loads of FCs in inland pollution sources ranged from $1.2{\times}10^9$ to $3.1{\times}10^{11}$ most probable number (MPN)/day; however, the pollutants could not be reached at the designated area. FC concentrations of seawaters were closely related to season, rainfall, and inland contaminants, however, within the regulation limit of various countries for shellfish. The highest concentrations for chemical oxygen demand (COD) and $chlorophyll-{\alpha}$ in seawaters were shown in the surface layer during August with high rainfall, whereas the lowest for dissolved oxygen (DO) in the bottom layer of the same month. Therefore, it indicates that the concentrations of FC, COD, DO, and $chlorophyll-{\alpha}$ of seawaters were closely related to season and rainfall.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.682-688
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• 2013

In this study, we investigated about cell toxicity and oxidative stress of HepG2 cell by treatment of sodium fluoride (NaF) and fluoride extracts from krill Euphausia superba meat, shell, whole body and krill meal. The cell toxicity showed significant at 300 and $500{\mu}g/mL$ NaF treatment group. But krill (Euphausia superba) fluoride extract (KFE) treatment in all groups were not toxic. The superoxide radical production increased significantly in NaF treated group, but there was no significant change in KFE treated group. The superoxide dismutase activity was a significant increase 21.5% at $100{\mu}g/mL$ and 24.7% at $300{\mu}g/mL$ treatment group of fluoride extracts from krill meat, and 8.7% at $300{\mu}g/mL$ in krill meals, compared to the control group. However, hydroxy radical flux and catalase and glutathione peroxidase activity of fluoride extracts from krill meat did not change. As a result, for a short period of time, NaF treatment in HepG2 cells affect the cell toxicity and oxidative stress, but in the case of KFE, these were not recognized. Thus, depending on the type of food ingested with fluoride, cell toxicity and oxidative stress was found to be different.

• Journal of Information Technology and Architecture
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• v.11 no.1
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• pp.45-52
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• 2014

Recently, more and more hospitals have become interested in the innovation of healthcare services and processes through IT convergence based on RFID, NFC, smart devices and so on. This paper presents a case of process innovation by implementing a smart health checkup system using these advanced information technologies. The existing inefficient health checkup process based on the paper chart and manual work has been innovated using the advanced information and communication technologies. The newly developed smart health checkup system has been used successfully in a tertiary university hospital named Samsung Medical Center since April 2013. The contributions of the system include improvement of service quality, enhancement of customer satisfaction, reduction in workload of staffs, improvement of work accuracy, and accordingly reinforcement of the competitiveness of the hospital.