• Microbiology and Biotechnology Letters
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• v.29 no.4
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• pp.227-233
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• 2001

To maximize astaxanthin (3,3'-dihydroxy-$\beta\beta$'carotene-44'-dione) production by high density Haematococcus pluvialis cultures, various, media were examined Among tested media, \`Hong Kong Medium and Modified Bolds Basal Medium showed the best result for cell growth ( $2.0$\times$10^{ 6}$cells /mL) and for astaxanthin content per cell (9.7 mg astaxanthin mg/g cell), respectively, Maximum astasanthin concentration of 6.1mL was obtained at pH 7.5, $20^{\circ}C$~$25^{\circ}C$ Deficiencies of nitrogen source($NaNO_3$ and proteose-peptone) found to simulate astaxanthin formation Relatively low light inten- sity of $60\mu$E ($\m^2$s) was sutiable for vegetative cell growth while higher light intensity was required for higher astaxanthin accumulation.

• Advances in concrete construction
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• v.10 no.4
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• pp.301-310
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• 2020

The following paper concentrates on the objective of studying the influences of extent of duration and temperature on the Pozzolanic properties as well as reactivity of locally existing natural clay of Nai Gaj, district Dadu, Sindh Pakistan. The activation of the clay only occurs through heating when temperature in a furnace chamber reaches 600, 700 and 800oC for 1, 2 and 3 hours and at 900 and 1000℃ for 1 and 2 hours. Furthermore, the strength activity index (SAI) of advanced pozzolanic material happens to be identified through 20% cement replacement for different samples of calcined clay as per ASTM C-618. The compressive strength test of samples had been operated for 7 and 28-days curing afterwards. The maximum compressive strength had been seen in mix E in which cement was replaced with clay calcined at 700℃ for 1 hour that is 27.05 MPa that is 24.31% more than that of control mix. The results gathered from the SAI verdicts the optimal activation temperature is 700℃ within a one-hour time period. The SAI at a temperature of 700℃ with a one-hour duration at 28 days is 124.31% which happens to satisfy the requirements of the new Pozzolanic material, in order to be applied in mortar/concrete (i.e., 75%). The Energy- dispersive spectrometry (EDS) along with the X-ray diffraction (XRD) have been carried out in means of verifying whether there is silica content or amorphous silica present in metakaolin that has been developed. The findings gathered from the SAI were validated, as the analysis of XRD verified that there is in fact Pozzolanic activity of developed metakaolin. Additionally, based on observation, the activated metakaolin holds a significant influence on the increase in mortar's compressive strength.

• Analytical Science and Technology
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• v.14 no.5
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• pp.432-441
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• 2001

An automated on-line portable preconcentration-short column gas chromatograph was developed, which used preconcentrator using adsorption tube with Tenax-GR and Curie-point heating. The developed system operated with 3 steps of processing, preconcentration, thermal desorption, and analysis and cleaning, and could continued operating within 1~2 min cycle. The recoveries of preconcentrator for toluene was ranged between $94.7{\pm}6.6%$ and $103.8{\pm}3.1%$ with less than 7% of RSD. For benzene, toluene and xylene(BTX) standard gas test, IDL was 41, 49, $472ng/m^3$ benzene, toluene and o-xylene, respectively. The BTX mixture was analyzed within 30 sec with baseline separation by the system equipped with 4 m long capillary column. The deficiency of separation power caused by short column was solved by the control of sample injection volume and inlet/outlet pressure ratio. The automated portable preconcentration-short column gas chromatograph system was found to be useful for the continuous air monitoring of BTX at ppb levels in ambient air.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.413-419
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• 2011

Diagnosis X-ray equipment localized at 1950's but it is developed suddenly at 1960's with demand together. Manufacture of Diagnostic X-ray equipment is controled by the KS regulation and the Ministry of Health and Welfare because of hazardous element etc. exposure by radiation. Most of diagnostic X-ray equipment ware single phase and three phase full-wave rectification but from 1980's it transforms it was exchanged in inverter type X-ray equipment. Inverter type X-ray equipment produces approximately 50~80% more average photon intensity then single phase full-wave rectification and the accuracy is high. But from a clinic it dose not use because expensive therefor the efficiency improvement of single phase full-wave rectification is necessary. We produced single phase full-wave rectification X-ray equipment control unit, high tension transformer, filament heating transformer, rectification circuit, high tension cable and others and evaluated efficiency, in result which is excellent compare with Rule of Safety Management and KS regulation.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.177-183
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• 2002

The extracts from approximately 40 different Korean traditional medicines were prepared to investigate the antimicrobial activities against poultry disease-related bacteria. Among tested, the extracts of Schizandra chinensis (SC), Melia azedarach (MA), Caesalpinia sappan (CS) and Rhus javanica (RJ) exhibited significant antimicrobial activities against Salmonella gallinarum, whereas the extracts of Elsholtzia ciliata (EC), Myristica fragrans (MF), Alpinia katsumadai (AK), Poncirus trifoliata (PT), Prunella vulgaris (PV), CS and RJ exhibited antimicrobial activities against Staphylococcus aureus. Minimum inhibitory concentrations (MIC) of MA, CS and RJ extracts against S. gallinarum were 1.2 mg/ml, whereas MIC of RJ extract for S. aureus was 0.6 ㎎/ml, which was the lowest among tested. The antimicrobial activities of SC and RJ extracts against S. gallinarum were reduced, but those of AK and CS extracts against S. aureus were not affected by heating treatment. The antimicrobial activities of SC extract against S. gallinarum and those of EC, PT and RJ extracts against S. aureus were stable by acid treatment but unstable by alkaline treatment. those of CS extract was not effected by either acid or alkaline treatment. The growth of all bacteria was significantly inhibited within 24 hours by the addition of at least 100 ppm and 300 ppm of RJ and CS extracts, respectively, compared with the control group. In conclusion, these findings suggest that RJ and CS extracts may play important roles for antimicrobial activities against poultry disease-related bacteria.

• The Journal of the Korea Contents Association
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• v.9 no.11
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• pp.247-253
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• 2009

We investigated the cell growth rate according to the change of temperature of the Thermo-rod used for the local hyperthermia therapy. For this study, we fabricated the Thermo-rods (TR) using Duplex Stainless Steels having magnetic properties as well as non magnetic properties. To evaluate cell growth rates up to 15 days, we conducted cell proliferation test using cell counting methods. For the tests, the CAPEs and Osteoblats were seeded on the 6-we11 plates with the induction heated thermo-rods 30 mins a day for 15 days with 2 days interval and without induction heated thermo-rods as control group respectively. We calculated cell growth rates, 6 hours after heating. From the results, in case of CAPEs and Osteobalsts seeded groups, the cell growth rates in all groups increased drastically for 6 days after seeding, but decreased irregularly after 6 days. In conclusion, the cell growth rates showed no significant difference among all groups and it indicated that there were no effects of temperate ($41^{\circ}C$) on cell growth rates.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.588-595
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• 2020

Prediction and control of nitrogen oxides (NO_x) emission is of great interest in industry due to stricter environmental regulations. Herein, we propose an artificial intelligence (AI)-based framework for prediction of NO_x emission. The framework includes pre-processing of data for training of neural networks and evaluation of the AI-based models. In this work, Long-Short-Term Memory (LSTM), one of the recurrent neural networks, was adopted to reflect the time series characteristics of NO_x emissions. A decision tree was used to determine a time window of LSTM prior to training of the network. The neural network was trained with operational data from a heating furnace. The optimal model was obtained by optimizing hyper-parameters. The LSTM model provided a reliable prediction of NO_x emission for both training and test data, showing an accuracy of 93% or more. The application of the proposed AI-based framework will provide new opportunities for predicting the emission of various air pollutants with time series characteristics.

• Biomedical Science Letters
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• v.11 no.3
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• pp.343-347
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• 2005

Bambusae caulis in Liquamen is one of the important herbal medicine produced by heating bamboo indirectly and is used for treatment of stroke, hypertension, and diabetes etc. Recently the mechanism of clinical effects on Bambusae caulis in Liquamen has been studied. This experiment was conducted to confirm the clinical effects of Bambusae caulis in Liquamen on type 1 diabetes and its related mechanism. We divided C57BL/6 mice into 3 groups and induced them to be type 1 diabetes by injection of streptozocin into peritoneum. The dosage of each group was 150 mg/kg once only, 140 mg/kg once only and 40 mg/kg for 5 days respectively. The two groups injected streptozocin for once took orally Bambusae caulis in Liquamen after the induction of diabetes, and the other one group was given Bambusae caulis in Liquamen during the diabetes inducing period. As the result, the two diabetes-induced groups showed blood glucose decreasing effect by Bambusae caulis in Liquamen on an average, but they didn't show the signiftcant differences statistically. But Bambusae caulis in Liquamen showed the anti-diabetic effect suppressing blood sugar rising trend during the diabetes inducing peried (P<0.05). The anti-oxidative effect of Bambusae caulis in Liquamen was measured with the hypoxanthine/xanthine oxidase (HX/XOD) system. The quantity of ROS was measured using DCFDA reagent indirectly. As the result, $10\%$ solution of Bambusae caulis in Liquamen showed anti-oxidative effect by scavenging $93.4\%$ superoxide as compared with control group. It is suspected that the anti-oxidative effect of Bambusae caulis in Liquamen suppressed the increase of blood glucose in the diabetes-inducing group. These results could be useful data to understand the effect of Bambusae caulis in Liquamen on type 1 diabetes and type 1 diabetes developing because ROS were closely connected with the induction and complications of diabetes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.817-822
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• 2017

The braking system is one of the most important components in vehicles and machines. It must exert a reliable braking force when they are brought to a halt. Generally, frictional heat is generated by converting kinetic energy into heat energy through friction. As the kinetic energy is converted into heat energy, high temperature heat is generated which affects the mechanical behavior of the braking system. Frictional heat affects the thermal expansion and friction coefficient of the brake system. If the temperature is not controlled, the brake performance will be decreased. Therefore, it is important to predict and control the heat generation of the brake. Various numerical analysis studies have been carried out to predict the frictional heat, but they assumed the existence of boundary conditions in the numerical analysis to simulate the frictional heat, because the simulation of frictional heat is difficult and time consuming. The results were based on the assumption that the frictional heat is different from the actual temperature distribution in a rotating brake system. Therefore, the reliability of the cooling effect or thermal stress using the results of these studies is insufficient. In order to overcome these limitations and establish a simulation procedure to predict the frictional heat, this study directly simulates the frictional heat generation by using a thermal-structure coupling element. In this study, we analyzed the thermo-mechanical behavior of a brake model, in order to investigate the thermal characteristics of brake systems by using the Finite Element method (FEM). This study suggests the necessity to directly simulate the frictional heating and it is hoped that it can provide the necessary information for simulations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.5
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• pp.551-556
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• 1992

To develop natural antioxidant from spices and control thermal oxidation of edible soybean oil, the available antioxidative compounds of various spices were extracted with edible soybean oil. The storage stability of the oil mixed with purified sardine oil and soybean oil containing that extracts at $37^{\circ}C$ were investigated. Furthermore the antioxidative activity of petroleum ether soluble fractions(PESF) obtained from rosemary on the thermal oxidation of edible soybean oil during heating at $180^{\circ}C$ were also investigated. By mixing with refined sardine oil and soybean oil extracts of rosemary, sage of herb spices and mace of seed spices, the oxidative stabilities were remarkably increased. The thermal oxidation of edible soybean oil was also supressed by the addition of 1.0%(w/w) of PESF obtained from rosemary. Rosemary extract exhibited higher antioxidative activity on thermal oxidation of edible soybean oil than butylated hydroxytoluene.