• Korean Journal of Veterinary Service
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• v.28 no.3
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• pp.203-213
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• 2005

Oxytetracycline, tetracycline, chlortetracycline and doxycycline in honey were separated by solid phase extraction (SPE) and determined with high performance liquid chromatography (HPLC) with UV/Visible detector. Analysis was carried out using following conditions: XTerra $C_8$ column $(3.9\times150mm\;i.d. 5{\mu}m)$, mobile phase composed of 0.01M oxalic acid : methanol : acetonitrile (820 : 80 : 100, v/v/v), isocratic pump at a flow rate of 0.9 ml/min. and $50{\mu}l$ of injection volume, UV/Visible detector with wavelength of 360nm. The calibration curves of four tetracyclines showed linearity $(\gamma^2>0.999)$ at concentration range of $100\~1,000 ng/ml$. The recoveries in fortified honey represented more than $70\%$ with low coefficient of variation $(<10\%)$ for concentration range of four tetracyclines. The detection limits for oxytetracycline, tetracycline, chlortetracycline and doxycycline were 13.8, 14.6, 26.2 and 24.9ng/g in acacia honey. respectively. We also monitored tetracyclines residue in domestic honey [n : 38, acacia (20), wild flower (18) ] and foreign honey [n=22, legally distributed (13), illegally distributed (9)] using modified Charm II screening and HPLC confirmation methods. Seven of the 60 samples $(11.7\%)$ were suspect positive using modified Charm II screening test. Chlortetracycline residue was found in one foreign honey (illegally distributed) tested at concentrations of 0.22 ppm. Conclusively, for more effective control of tetracyclines used in beekeeping should be further survey for residues in honey and also national guidelines (maximum residue limit : MRL) and methods should be obligatory.

• Korean Journal of Veterinary Service
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• v.28 no.3
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• pp.225-234
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• 2005

Egg has been considered as one of the most important food sources in both nutritionally and economically. However, because the hazards of egg flow chains' complexity from producers to consumers and the insufficiency of cold chain systems in Korea are still remained, preventive measures for egg safety should be established. This experiment was carried out to investigate the changes of egg qualify during storage in order to find out the proper storage condition and eggshell treatment. Eggs were stored at cold condition $(5^{\circ}C,\;relative\;humidity;\;RH:\;65\pm3\%)$ and room Condition $(1st: Sep\; 6\~Nov\; 15,\;2001,\; 10\~30^{\circ}C,\;RH\;41\~86\%,\;2nd;\; Dec\;13,\;2001\~Feb\;21,\;2002,\;4\~23^{\circ}C,\;RH\;36\~89\%)$ after eggshell treatment (unwashed, washed and coated egg) during'10 weeks and examined weight loss and interior quality periodically. Weight loss was in decreasing order room washed > room unwashed > cold washed > cold unwashed > room coated > cold coated egg. And, Haugh unit was decreasing order room washed > room unwashed > room coated > cold washed > cold unwashed > cold coated egg. Our findings show that both coated eggs and refrigeration reduces the rate of decline in Haugh units and egg weight. And, washed eggs had lower average Haugh units and a higher weight loss than any of the eggshell treatment in both storage conditions. Conclusively, for washing eggshell, 150 ppm of sodium hypochlorite, regular exchange and temperature control of water should be consistent and also eggs should be dried immediately after washing. Also, national guidelines for temperature and moisture of storage places, transportation and expiration data should be established to keep quality and weight loss of eggs. Storage temperature that is a critical factor in the quality and safety of eggs should be kept under 12'c and labelling of expiration date should be obligatory.

• Journal of Korean Society on Water Environment
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• v.33 no.6
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• pp.680-688
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• 2017

Water quality monitoring for flow rates and BOD/COD/T-N/T-P/SS/TOC concentrations has been conducted in Nakdong river tributaries since 2011. In this study concentrations and loading rates of BOD, T-P, and TOC were analyzed to evaluate water quality monitoring stations using accumulated data at 206 tributary monitoring stations in Nakdong river 2012 ~ 2016. Average concentration ranges for 206 monitoring stations were 0.3 ~ 6.4 mg/L, 0.025 ~ 1.562 mg/L, and 0.6 ~ 10.7 mg/L for BOD, T-P, and TOC, respectively. Additionally, average loading rate ranges were 0.96 ~ 46,040 kg/d, 0.087 ~ 1,834 kg/d, and 1.51 ~ 80,425 kg/d for BOD, T-P, and TOC, respectively. Average concentration for BOD, T-P, and TOC at each monitoring station was evaluated using ambient water quality standards of rivers and water quality regulation level for medium-sized management areas. Average loading rate and specific loading rate (loading rate/drainage basin area) for BOD, T-P, and TOC at each monitoring station was considered to evaluate monitoring stations using suggested classification (BOD, TOC: -1, 1 ~ 10, 10 ~ 100, 100 ~ 1,000, and 1,000 ~ kg/d; T-P: -0.1. 0.1 ~ 1, 1 ~ 10, 10 ~ 100, and 100 ~ kg/d) Using results of this study, various water quality status maps were provided, and three evaluation methods were suggested to determine priority monitoring stations in Nakdong river for rational water quality control and tributaries basin management.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.581-589
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• 2011

Generally, treated water or raw water is transported into storage reservoirs which are receiving facilities of local governments from multi-regional water supply systems. A water supply control and operation center is operated not only to manage the water facilities more economically and efficiently but also to mitigate the shortage of water resources due to the increase in water consumption. To achieve the goal, important information such as the flow-rate in the systems, water levels of storage reservoirs or tanks, and pump-operation schedule should be considered based on the resonable water demand forecasting. However, it is difficult to acquire the pattern of water demand used in local government, since the operating information is not shared between multi-regional and local water systems. The pattern of water demand is irregular and unpredictable. Also, additional changes such as an abrupt accident and frequent changes of electric power rates could occur. Consequently, it is not easy to forecast accurate water demands. Therefore, it is necessary to introduce a short-term water demands forecasting and to develop an application of the forecasting models. In this study, the forecasting simulator for water demand is developed based on mathematical and neural network methods as linear and non-linear models to implement the optimal water demands forecasting. It is shown that MLP(Multi-Layered Perceptron) and ANFIS(Adaptive Neuro-Fuzzy Inference System) can be applied to obtain better forecasting results in multi-regional water supply systems with a large scale and local water supply systems with small or medium scale than conventional methods, respectively.

• Journal of Chest Surgery
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• v.19 no.3
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• pp.443-448
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• 1986

Aortic dissection is a serious disease that mortality does not approach to zero despite of medical and surgical improvement. Recently two cases of aortic dissection were treated with good results by the two other methods. Case 1 [57-Y-0-Male]; Chief complaint was chest pain radiating to the back. Preoperatively he was controlled by Minipress, dichlotride, & sodium nitroprusside. Aortography showed DeBakey Type III aortic dissection extending from just below the Lt. subclavian artery to the proximal portion of the origin of the renal artery. Through the midline long incision Flow reversal & Thrombo-exclusion method was used, and bypass course was proximal anastomosis at the ascending aorta - through the Rt. thoracic cavity - midportion of the diaphragm - posterior to the liver, stomach, & pancreas - distal anastomosis at the abdominal aorta proximal to its bifurcation. Bypass graft was preclotted 20 mm Dacron Woven Graft, and the aortic arch between the Lt. subclavian artery & Lt. common carotid artery was divided and meticulously sutured. Control aortogram which was done at 4th postoperative month revealed obstruction of the false lumen by thrombosis, and complications were not noticed. Case 2 [53-Y-0-Male]; Chief complaint was chest pain radiating to the abdomen. DeBakey Type III aortic dissection which was similar to the case 1 was detected by the aortography, and involvement of the Lt. subclavian & common carotid arteries was suspicious. Through the Lt. posterolateral thoracotomy the Ringed Intraluminal Sutureless Graft, No. 22 mm, was inserted from just below the Lt. common carotid artery to the midportion of the descending thoracic aorta under total circulation arrest using a F-F bypass, and the Lt. subclavian artery was ligated. Postoperatively hospital course was uneventful with antihypertensive drugs, and any specific complications were not noticed.

• Journal of Wetlands Research
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• v.19 no.3
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• pp.287-295
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• 2017

In this study, rainfall runoff characteristics according to peak concentration were analyzed using the water quality and flow data in the Geumho river, and the direction of nonpoint source management such as monitoring and management period by pollution source was derived. Peak Water Quality Concentration is the concept that utilizes the extreme value as the concentration of non-point pollution control standard with the highest water quality in the rainwater runoff. Using this method, the evaluation factors such as cumulative precipitation(total precipitation), peak water quality concentration, cumulative precipitation up to peak water quality concentration, time to peak water quality concentration, and EMC to peak water quality concentration were examined and long- Rainfall runoff characteristics of nonpoint sources were analyzed. The results of the analysis suggested proper monitoring and management method to manage nonpoint source.

• Geomechanics and Engineering
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• v.23 no.1
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• pp.85-92
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• 2020

This study adopted soil test and laboratory physical model experiments to simulate the tailings impoundment accumulation process according to the principle of similarity. Relying on the practical engineering, it analyzed the tailings deposition characteristics on dry beach surface during the damming process, as well as the variation rules of dam saturation line. Results suggested that, the tailings particles gradually became finer along the dry beach surface to inside the impoundment. The particle size suddenly changed at the junction between the deposited beach and the water surface, which displayed an obvious coarsening phenomenon. Besides, the deposited beach exhibited the vertical feature of coarse upward and fine downward on the whole. Additionally, in the physical model, the saturation line elevated with the increase in dam height, and its amplitude was relatively obvious within the range of 1.0-4.5 m away from the initial dam. Under flood condition, the saturation line height was higher than that under normal condition on the whole, with the maximum height difference of 4 cm. This study could provide an important theoretical basis for further studies on dam failure experiments and the evolution rules of leaked tailings flow.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.523-523
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• 2012

As the wafer geometric requirements continuously complicated and minutes in tens of nanometers, the expectation of real-time add-on sensors for in-situ plasma process monitoring is rapidly increasing. Various industry applications, utilizing plasma impedance monitor (PIM) and optical emission spectroscopy (OES), on etch end point detection, etch chemistry investigation, health monitoring, fault detection and classification, and advanced process control are good examples. However, process monitoring in semiconductor manufacturing industry requires non-invasiveness. The hypothesis behind the optical monitoring of plasma induced ion current is for the monitoring of plasma induced charging damage in non-invasive optical way. In plasma dielectric via etching, the bombardment of reactive ions on exposed conductor patterns may induce electrical current. Induced electrical charge can further flow down to device level, and accumulated charges in the consecutive plasma processes during back-end metallization can create plasma induced charging damage to shift the threshold voltage of device. As a preliminary research for the hypothesis, we performed two phases experiment to measure the plasma induced current in etch environmental condition. We fabricated electrical test circuits to convert induced current to flickering frequency of LED output, and the flickering frequency was measured by high speed optical plasma monitoring system (OPMS) in 10 kHz. Current-frequency calibration was done in offline by applying stepwise current increase while LED flickering was measured. Once the performance of the test circuits was evaluated, a metal pad for collecting ion bombardment during plasma etch condition was placed inside etch chamber, and the LED output frequency was measured in real-time. It was successful to acquire high speed optical emission data acquisition in 10 kHz. Offline measurement with the test circuitry was satisfactory, and we are continuously investigating the potential of real-time in-situ plasma induce current measurement via OPMS.

• Journal of Pharmaceutical Investigation
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• v.22 no.3
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• pp.197-204
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• 1992

A gas chromatographic method using nitrogen phosphorous selective detection was developed for simultaneous determination of haloperidol and its metabolite, reduced haloperidol, in human plasma. Combelen was used as internal standard, The method involved extraction and trimethylsilylation followed by the injection of $2-4\;{\mu}l$ of benzene layer, which was used to dissolve the trimethylsilylated derivatives of haloperidol and reduced haloperidol, onto SE-54 column [5% phenyl methyl silica fused capillary column, $16m{\times}0.22\;mm$ $(I.D.){\times}0.33\;{\mu}m$ (coated thickness)]. The temperature of column oven was programmed from $200^{\circ}C\;to\;300^{\circ}C$ at the increase rate of $10^{\circ}C/min and also the temperatures of injector and detector were set at $300^{\circ}C$. Helium was used as carrier gas and its flow rate was maintained at 30 ml/min. The detection was conducted with nitrogen phosphorous selective detector. The retention times for combelen, reduced haloperidol and haloperidol were found to be 9.14, 9.75 and 9.99 min, respectively. The detection limits for haloperidol and reduced haloperidol in human plasma were both 0.2 ng/ml. The coefficients of variation of the intra-assay were generally low (below 9.8%). The mean absolute recoveries of added haloperidol and reduced haloperidol from plasma were 72% and 84%, respectively. No interferences from endogenous substances were found.

• Journal of Pharmaceutical Investigation
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• v.22 no.3
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• pp.219-227
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• 1992

The influence of phenobarbital (PB) pretreatment (75 mg/kg/day, i.p. for 4 days) on the pharmacokinetics of diltiazem (DTZ) and its metabolite, desacetyldiltiazem (DAD), was investigated in rats. DTZ was injected via femoral (3 mg/kg) or portal (10 mg/kg) vein to the control and PB-pretreated rats. DAD was also injected separately via femoral (3 mg/kg) vein to both groups of rats. The intrinsic hepatic plasma clearance of DTZ was found to be significantly increased (6.8-fold) by the PB pretreatment. However, the fraction of an intravenous DTZ dose converted to DAD $(F_mi)$ was only slightly (6%) increased and calculated metabolic rate constant of DTZ to DAD was not affected by the pretreatment. On the other hand, plasma free fraction of DTZ was increased (1.8-fold) from $4.24{\pm}0.25%$ to $7.45{\pm}0.54%$ by the pretreatment. However, the l.8-fold increase in the free fraction of DTZ would not explain the 6.8-fold increase in the hepatic intrinsic clearance of DTZ. Therefore, the increase in either the hepatic blood flow or the metabolism other than to DAD was expected as the probable mechanism(s) of the increased hepatic clearance of DTZ. Sequential metabolism of DAD to further metabolites, however, would be a more potential cause of the apparently unchanged metabolism of DTZ to DAD by the PB-pretreatment.