• Particle and aerosol research
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• v.18 no.1
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• pp.9-21
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• 2022

In this study, a novel antiviral coating method for the air filtration system of subway station was investigated. Using dry aerosol coating process, we developed a high-performance antiviral air filter with spark discharger and carbon brush type ionizer. Silver nanoparticles were produced by a spark discharge generation system with ion injection system and were used as antiviral agents coated onto a medium grade air filter. The pressure drop, filtration efficiency, and antiviral ability of the filter against aerosolized MS2 virus particles as a surrogate of SARS-CoV-2 virus were tested with dust contamination. Dust contamination caused the increase of the filtration efficiency and pressure drop, while the antiviral agents (in this study, silver nanoparticles) coating did not have any significant effect on the filtration efficiency and pressure drop. Using these properties, we suggested a novel method to maximize the antiviral performance of the antiviral air filter that was contaminated by dust particles. Moreover theoretical analysis of antiviral ability with dust contamination and re-coated antiviral agents was carried out using a mathematical model to calculate the time-dependent antiviral effect of the filter under actual conditions of subway station. Our model can be used to apply on antiviral air filtration system of subway station for prevention of pandemic diffusion, and predict the life cycle of an antiviral filter.

• Journal of Korea Water Resources Association
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• v.54 no.spc1
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• pp.1195-1204
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• 2021

Recently, local torrential rain have become more frequent and severe due to abnormal climate conditions, causing a surge in human and properties damage including infrastructures along the river. In this study, water surface elevation prediction algorithm was developed using the LSTM (Long Short-term Memory) technique specialized for time series data among Machine Learning to estimate and prevent flooding of the facilities. The study area is Jamsu Bridge, the study period is 6 years (2015~2020) of June, July and August and the water surface elevation of the Jamsu Bridge after 3 hours was predicted. Input data set is composed of the water surface elevation of Jamsu Bridge (EL.m), the amount of discharge from Paldang Dam (m³/s), the tide level of Ganghwa Bridge (cm) and the number of tweets in Seoul. Complementary data were constructed by using not only structured data mainly used in precedent research but also unstructured data constructed through wordcloud, and the role of unstructured data was presented through comparison and analysis of whether or not unstructured data was used. When predicting the water surface elevation of the Jamsu Bridge, the accuracy of prediction was improved and realized that complementary data could be conservative alerts to reduce casualties. In this study, it was concluded that the use of complementary data was relatively effective in providing the user's safety and convenience of riverside infrastructure. In the future, more accurate water surface elevation prediction would be expected through the addition of types of unstructured data or detailed pre-processing of input data.

• The Journal of Internal Korean Medicine
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• v.42 no.2
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• pp.140-151
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• 2021

The aim of this study is to report the effectiveness of a traditional Korean medicine treatment for oculomotor nerve palsy induced by traumatic subarachnoid hemorrhage. A 54-year-old male patient with oculomotor nerve palsy induced by traumatic subarachnoid hemorrhage after a traffic accident was treated with Korean medicine, including acupuncture, electroacupuncture, sweet bee venom pharmacoacupuction, moxibustion, and herbal medicine. The effect of treatment on symptoms - ptosis, and eye movement - was evaluated using a ratio of eye opening and eye movement between the paralyzed eye and the normal eye. After 41 days of treatment, the clinical symptoms had improved. The ptosis and eye movement started to show improvement from day 20; at the time of discharge, ptosis had improved by more than 50%, and eye movement showed some improvement as well. This study suggests that Korean medicine may be an effective treatment for oculomotor nerve palsy induced by traumatic subarachnoid hemorrhage.

• Journal of Korea Water Resources Association
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• v.55 no.5
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• pp.383-392
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• 2022

The restoration of the Nakdong River estuary is one of the most important projects of the Ministry of Environment, Republic of Korea. A real-scale experiment of gate operation was executed from 2019 to 2020, and a pilot operation was performed in 2021. The gate of Nakdong River Estuary Barrier (NEB) is supposed to be continuously opened based on the experiment results. Many critical decisions should be made immediately during the experiment based on the real-time measured data and numerical analysis considering the seawater inflows. The decision-making sequence was made systematically with the accurate estimation of seawater inflow. The estimation of seawater inflow is the main research objective and the equations of seawater inflow were developed, reflecting the structural characteristics of NEB. The inflow equations were developed in two forms, overflow and underflow. ADCP (Acoustic Doppler Current Profiler) was used to measure seawater inflow, check the accuracy of the developed equations, and derive the flow coefficient. The comparison error of the developed equations was about 3% compared to the measured data.

• Journal of Korea Water Resources Association
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• v.55 no.12
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• pp.991-998
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• 2022

The purpose of this study is to develop GPU (Graphics Processing Unit) acceleration technique for 2-dimensional model and to assess the effectiveness for high resolution flood simulation in wide area In this study, GPU acceleration technique was implemented in the G2D (Grid based 2-Dimensional land surface flood model) model, using implicit scheme and uniform square grid, by using CUDA. The technique was applied to flood simulation in Jinju-si. The spatial resolution of the simulation domain is 10 m × 10 m, and the number of cells to calculate is 5,090,611. Flood period by typhoon Mitag, December 2019, was simulated. Rainfall radar data was applied to source term and measured discharge of Namgang-Dam (Ilryu-moon) and measured stream flow of Jinju-si (Oksan-gyo) were applied to boundary conditions. From this study, 2-dimensional flood model could be implemented to reproduce the measured water level in Nam-gang (Riv.). The results of GPU acceleration technique showed more faster flood simulation than the serial and parallel simulation using CPU (Central Processing Unit). This study can contribute to the study of developing GPU acceleration technique for 2-dimensional flood model using implicit scheme and simulating land surface flood in wide area.

• Journal of Physiology & Pathology in Korean Medicine
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• v.36 no.4
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• pp.138-142
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• 2022

This study aimed to evaluate the effectiveness of Korean rehabilitation treatement for patients with post-TKR. The medical records of inpatients undergoing Korean rehabilitation treatment after TKR from 2016.01.01. to 2021.12.31. during the admission, were analyzed retrospectively. The effect of treatment was evaluated by using a numeric rating scale(NRS) and range of motion(ROM) of knee. Statistical analysis was done using the IBM SPSS statistics 26 program. If the period of hospitalization was within 7 days or change of NRS and ROM was not recorded properly, the case was excluded. All inpatients received acupuncture treatment, Electro-acupuncture. Soyeom pharmaco-acupuncture were used at a high rate. Blood letting cupping therapy, dry cupping therapy, Interferential Current Therapy(ICT) continuous passive motion(CPM), cryotherapy were used at a high rate. A significant improvement was noted when comparing the NRS and knee ROM results at the time of admission and discharge. Korean medical rehabilitation can be effectively used for patients who have undergone TKR, to relieve pain and enable returning to daily activities. It is expected to be helpful in future studies of post-TKR in Korean Medicine. Also It can be used for medical treatment of post-TKR in Korean Medicine Hospital and clinic. However, further research with a high level of evidence is necessary to support this finding.

• Journal of the Korea Society of Computer and Information
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• v.27 no.8
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• pp.161-168
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• 2022

In this study, a survey on the wearing satisfaction of commercial men's upper body correction underwear was conducted targeting mildly obese men in their twenties, and it was intended to suggest improvement points for the correction underwear. The product used for the study was Adapt's 95 PROBLEM, and 15 subjects were selected as males in their 20s with a BMI of 25-30 (mild obesity). As a result, men's awareness and interest in corrective underwear were low. In the wearing satisfaction survey, 74% of those who answered negatively that it was uncomfortable to wear and take off. In terms of pressure relief, 60% of those who felt the pressure was strong at the beginning, but as time passed, they got used to it and answered that there was no major inconvenience. However, with regard to digestion after a meal, 40% of the subjects felt that the pressure interfered with digestion. There were many deficiencies in terms of functionality, with more than half of those who responded negatively with regard to stuffiness and heat, and many negative opinions regarding sweat absorption and discharge. In the visual section, positive reaction was shown in chest, side waist and front waist correction, and among them, the front waist had the highest score. In conclusion, it seems that functional parts related to heat and sweat must be improved in consideration of the stuffiness and indigestion brought about by excessive pressure for men's upper body correction underwear.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.1
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• pp.8-17
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• 2023

In conventional liquid crystal display(LCD) manufacturing process, Indium Tin Oxide(ITO) as transparent electrode and rubbing process of polyimide as alignment layer are essential process to apply electric field and align liquid crystal molecules. However, there are some limits that deposition of ITO requires high vacuum state, and rubbing process might damage the device with tribolectric discharge. In this paper, we made nanocomposite with PEDOT:PSS and MWNT to replace ITO and constructed alignment layer by nano imprint lithography with nano wrinkle pattern, to replace rubbing process. These replacement made that only one PEDOT:PSS/MWNT film can function as two layers of ITO and polyimide alignment layer, which means simplification of process. Transferred nano wrinkle patterns functioned well as alignment layer, and we found out lowered threshold voltage and shortened response time as MWNT content increase, which is related to increment of electric conductivity of the film. Through this study, it may able to contribute to process simplification, reducing process cost, and suggesting a solution to disadvantage of rubbing process.

• Clean Technology
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• v.16 no.3
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• pp.191-197
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• 2010

Repair reaction of plasma damaged porous methyl doped SiOCH films was carried out with silylation agents dissolved in supercritical carbon dioxide ($scCO_2$) at various reaction time, pressure, and temperature. While a decrease in the characteristic bands at $3150{\sim}3560cm^{-1}$ was detectable, the difference of methyl peaks was not identified apparently in the FT-IR spectra. The surface hydrophobicity was rapidly recovered by the silylation. In order to induce effective repair in bulk phase, the wafer was heat treated before reaction under vacuum or ambient condition. The contact angle was slightly increased after the treatment and completely recovered after the subsequent silylation. Methyl groups were decreased after the plasma damage, but their recovery was not identified apparently from the FT-IR, spectroscopic ellipsometry, and secondary ion mass spectroscopy analyses. Furthermore, Ti evaporator was performed in a vacuum chamber to evaluate the pore sealing effect. The GDS analysis revealed that the open pores in the plasma damaged films were efficiently sealed with the silylation in $scCO_2$.

• Journal of Korea Water Resources Association
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• v.56 no.6
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• pp.373-380
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• 2023

Due to abnormal climate phenomena and climate change in Korea, overgrowth of algae in rivers and reservoirs occurs frequently. Algae in rivers are classified into green algae, blue-green algae, diatom, and other types, and some species of blue-green algae cause problems due to odor and the discharge of toxic substances. In Korea, an algae alert system is in place, and it is issued based on the number of harmful blue-green algae cells. Thus, measuring harmful blue-green algal blooms is very important, and currently, the analysis method of algae involves taking field samples and determining the cell count of green algae, blue-green algae, and diatoms through algal microscopy, which takes a lot of time. Recently, the analysis of algae concentration through Phycocyanin, an alternative indicator for the number of harmful algae cells, has been conducted through remote sensing. However, research on the analysis of the number of blue-green algae cells is currently insufficient. In this study, we water samples for algal analyses were collected from river and counted the number of blue-green algae cells using algae microscopy. We also obtained the Phycocyanin concentration using an optical sensor and acquired algae spectra through a hyperspectral sensor. Based on this, we calculated the equation for estimating blue-green algae cell counts and estimated the number of blue-green algae cells.