• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.1
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• pp.93-99
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• 2016

The extraction efficiency depending on the extracting methods and the conditions of extraction was investigated. The common steam extraction was compared to the distillation extraction method. The effects of the samples size and the extraction time on the extract yield were also investigated by using UV-Vis spectrophotometer. One of the functional components of pine needle extract as the natural phenol base components were detected by the UV-VIS at around 235 nm wavelength range. The absorbance intensity at around 235 nm wavelength of the pine needle extract was used as the indicator of the extraction efficiency in this experiment. The distillation extraction showed the higher extract yield than the steam extraction. The grinding treatment of pine needles also resulted in the better extract performance, but the severe grinding showed a little decrease in the extract yield especially in case of the distillation extraction method. More than half of the extract was collected at the first stage of the extraction, that was the first 15 minutes in the total 60 minutes extraction.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.539-546
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• 2008

A study on the selection of an optimal entrainer as the third component among water, aniline, 1,3-diethylbenzene, furfural, and MEK, for the extractive distillation of an azeotropic acetone/methanol system was performed using both the entrainer effect vapor-liquid equilibrium (VLE) and the relative volatility. In the case of water as the entrainer, a VLE curve without azeotropic point in the range of water composition from 0.3 up to 0.7 mole fraction could be obtained by both the experiment and the calculation using modified-UNIFAC model. For aniline and 1,3-diethylbenzene, however, VLE curve without azeotropic point could be obtained only at compositions above 0.7 mole fraction, which exhibited that they could be hardly utilized as the entrainer. Moreover, both furfural and MEK were verified to be improper entrainer since they formed an azeotropic phase. Relative volatility of water showed greater than 1.0 and increased with compositions, while those of the others decreased non-linearly, exhibiting that only water could be utilized as the proper entrainer for the extractive distillation of azeotropic acetone/methanol system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.154-158
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• 1999

Volatile flavor compounds from perilla leaves were extracted and analyzed with different methods, head-space analysis (HS), simultaneous steam distillation and extraction (SDE) , and solvent extraction (SE), and to compare their efficiencies for quick analysis. Over 30 volatile compounds were isolated and 28 compounds were identified by GC/MSD. Major compound was perillaketone showing the compositions of which were 92% in SDE method, 86% in headspace analysis, and 62% in solvent extraction method. For quick evaluation of leaf flavor in perilla, it was desirable because the headspace analysis method had a shorter analyzing time and smaller sample amount than the other methods.

• Membrane Journal
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• v.28 no.2
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• pp.83-89
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• 2018

Hydrophobic porous PVDF hollow fiber membranes for Membrane Distillation (MD) were fabricated by a combination of thermally induced phase separation (TIPS) and stretching. The purpose of this study is to investigate the shape and operating conditions of the module and the effect of piping size on parallel connection. In the optimization experiment of the vacuum membrane distillation module, the flux decreased as the packing density and length of the membrane in the module increased. When the module was connected vertically, it was confirmed that the nearest to the inlet of the vacuum port was the highest flux. In selecting the size of the header pipe of the module, it was confirmed that the maximum flux is shown when the inner diameter area of the hollow fiber membrane and the inner diameter area of the header pipe are the same. Also, it is necessary to find the optimal linear velocity because the higher the linear velocity in the module, the higher the flux, but the pressure acting on the module also increases proportionally.

• Membrane Journal
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• v.26 no.1
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• pp.70-75
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• 2016

The reuse of wastewater is being diffused to manage and develop the water resources. Generally, the treated wastewater is discharged to the river after being treated to meet the effluent quality standard or reused for diverse uses through the reprocessing. And recently, as the reuse of the treated wastewater is activated, the technologies to utilize for the high quality water resources such as industrial water by reusing the wastewater with Membrane Distillation (MD) are under development. In this study, the direct contact membrane distillation (DCMD) process has been applied to treat sewage discharge water for water reuse. The laboratory scale experiment was performed by using a hydrophobic PVDF membrane with the pore size of $0.22{\mu}m$. The influence of operating parameters, such as feed temperature, feed flow rate, feed concentration, on the permeate flux and rejection has been investigated. All filtration tests were conducted till the feed volume reached a concentration factor of 3.0. Thus, the operating period ranged between 19 hr and 49 hr depending on filtration performance. The results showed that above 92% of TN, TP, COD and TOC in the feed could be rejected regardless of an operating condition. The water flux was ranged from 13.8 to 20.3 LMH. The lowest flux was obtained at the operating condition with the feed temperature of $50^{\circ}C$ and feed flow velocity of 500 mL/min while the highest one was measured with $60^{\circ}C$ and 900 mL/min. When the concentration factor reached 3.0, water flux declined by approximately ranged from 14.5% to 33.3%. But the fouling in MD is almost fully reversible, with more than 90% recovery of permeate water flux following a DI water rinse without the addition of chemical cleaning reagents.

• Korean Journal of Pharmacognosy
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• v.1 no.3
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• pp.93-99
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• 1970

There have been reported by several workers for the isolation and determination of the amine derivatives as Metbylephedrine Hydrochloride and Ephedrine Hydrochloride adopting neutralization method, steam distillation method, non-aqous titration method, ion-exchange resin method, titration method after acetylation, colorimetric method, gravimetric method, iodine titration method and gas chromatography. Those methods mentioned in above, can be practically applied for the sample which is not mixed one mith the other amine compounds. Presently, it has not shown on the isolative determination of the mixed sample of amine derivatives. In this paper, it is discussed on the isolative determination of Methylephedrine Hydrochloride as the tertiary amine compound and Ephedrine Hydrochloride as the secondary amine compound. According to the results of the experiment, it could be summarized as follows: 1. There is no time-variation on the color reaction of Methylephedrine Hydrochloride and Ephedrine Hydrochloride with the color reagent, bromcresolgreen. And Methylephedrine Hydrochloride and Ephedrine Hydrochloride, respectively, can be determined spectrophotometrically by means oft his color reaction. 2. For the isolation of Methylephedrine Hydrochloride and Ephedrine Hydrochloride from the mixed sample, Methylephedrine Hydrochloride can be eluted by chloroform, while Ephedrine Hydrochloride by the mixed solvent of chloroform and ethylalcohol (2:1), from the celite column adsorbed at pH6.4 followed by extraction with ether undersodium hydroxide alkali re action. 3. When the sample is mixed with quinine hydrochloride, dihydrocodeine bitartate, and noscapine, these mixed compounds can be eliminated by means of stram distillation. 4. When the sample is mixed with chlorpheniramine maleate, dextromethorphan hydrobromide and diphenhydramine hydrochloride, the mixed compounds can be eliminated by means of steam distillation and celite adsorption column chromatography, In conclusion, the isolative determination method for Methylephedrine Hydrochloride and Ephedrine Hydrochloride studied in this paper, indicates with the excellent reproducibility and accuracy.

• Journal of Broadcast Engineering
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• v.28 no.3
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• pp.333-336
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• 2023

Recently, the transformer model used in natural language processing is also applied to the image super resolution field, showing good performance. However, these transformer based models have a disadvantage that they are difficult to use in small mobile devices because they are complex and have many learning parameters and require high hardware resources. Therefore, in this paper, we propose a knowledge distillation technique that can effectively reduce the size of a transformer based super resolution model. As a result of the experiment, it was confirmed that by applying the proposed technique to the student model with reduced number of transformer blocks, performance similar to or higher than that of the teacher model could be obtained.

• Journal of Physiology & Pathology in Korean Medicine
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• v.36 no.2
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• pp.54-58
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• 2022

This study aimed to investigate the anti-stress function of Aucklandiae Radix (AR) and Cyperi Rhizoma (CR). The essential oils used in the experiment were extracted from AR and CR using Steam Distillation Extraction and Super critical CO₂ extraction. To observe the effects of sample administration, we measured feed intake, leukocytes, red blood cells, hemoglobin, platelets, serum serotonin content, immobility time, climbing time, and swimming time in mice subjected to chronic restraint stress as behavioral changes. The average body weight of all experimental groups increased than the average body weight of the control group. The immobility and climbing times of experimental groups A and B administered with supercritical extraction samples were shorter than those of the other experimental groups and the control group, and the swimming time was longer. The serotonin content in the blood of all experimental groups decreased compared to the normal group, and the serotonin content of the control group was increased. The authors suggest that Korean herbal medicines AR and CR may be utilized as anti-stress flavoring agents based on the above results.

• Journal of Internet Technology
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• v.22 no.4
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• pp.903-911
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• 2021

As cyber-attacks on Cyber-Physical System (CPS) become more diverse and sophisticated, it is important to quickly detect malicious behaviors occurring in CPS. Since CPS can collect sensor data in near real time throughout the process, there have been many attempts to detect anomaly behavior through normal behavior learning from the perspective of data-driven security. However, since the CPS datasets are big data and most of the data are normal data, it has always been a great challenge to analyze the data and implement the anomaly detection model. In this paper, we propose and evaluate the Clustered Deep One-Class Classification (CD-OCC) model that combines the clustering algorithm and deep learning (DL) model using only a normal dataset for anomaly detection. We use auto-encoder to reduce the dimensions of the dataset and the K-means clustering algorithm to classify the normal data into the optimal cluster size. The DL model trains to predict clusters of normal data, and we can obtain logit values as outputs. The derived logit values are datasets that can better represent normal data in terms of knowledge distillation and are used as inputs to the OCC model. As a result of the experiment, the F1 score of the proposed model shows 0.93 and 0.83 in the SWaT and HAI dataset, respectively, and shows a significant performance improvement over other recent detectors such as Com-AE and SVM-RBF.

• Korean Journal of Medicinal Crop Science
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• v.17 no.6
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• pp.427-433
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• 2009

Volatile flavor compounds from the shoot and root of Angelica gigas Nakai were extracted by HE (Hydrodistillation extraction), SDE (Simultaneous steam distillation & extraction), and SFE (Supercritical fluid extraction system), and analyzed by GC-MS. The amount and the number of chemical components in essential oils from shoot and root by SFE was the higher than those by other extraction methods. Respectively, thirty one constituents were identified from the essential oil of the shoot and root by HE, twenty seven and twenty three constituents were identified from the essential oil of shoot and root by SDE, thirty one and forty five constituents were identified from the essential oil of shoot and root by SFE. The result showed large differences in extraction methods and in plant parts of Angelica gigas Nakai. Also, the bioactive compounds in root part was identified as nodakenin and decursinol (11.95% and 8.42%, respectively) by SFE. These results suggested that SFE was the best extraction method for the increasing of extraction yield, the determination of volatile components and the increasing of bioactive compounds in the shoot and root of Angelica gigas Nakai.