• Journal of the Korean Solar Energy Society
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• v.33 no.6
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• pp.12-18
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• 2013

Domestic solar hot water system can be divided into a passive type and an active type. In a passive type the storage tank is horizontally mounted immediately above the solar collectors. No pumping is required as the hot water naturally rises into the storage tank from the collectors through thermo-siphon flow. While, in an active type the storage tank is ground- or floor-mounted and is below the level of the collectors; a circulating pump moves water or heat transfer fluid between the storage tank and the collectors. We installed two types solar hot water systems consisting of the same storage tank and collectors at the same place, and were measured and compared typical operating characteristics under the same external conditions. In particular, the daily system performance was presented through the stirring test after the sunset. The results show that the amount of solar radiation obtained for an active type were less than a passive type on a cloudy day, because the operation of the circulation pump stops frequently took place on that day. However, on a sunny day, depending on the stable operation of the circulation pump, the amount of solar radiation obtained for an active type were increased than a passive type.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.942-944
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• 2017

High-speed vehicles are subjected to complex loads, such as acoustic pressure from the engine at launch and aerodynamic heating and aerodynamic pressure during flight. A thermal protection system panel is required to protect internal systems such as the fuel tank of the vehicle from the external environment. This study defines analytical models for heat transfer and thermal structure characteristics of the thermal protection system panel. Furthermore, the study performed parameters analysis to achieve the thermal structural integrity and to make it lighter.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.1
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• pp.19-28
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• 2011

More than 30,000 Wooden Slips were excavated in the Juyan region in 1930s and 1970s. These slips recorded military actions of Juyan Frontier Fortress during Han dynasty, which is about BC 100 ~ AD 30. On the slips, there are many disease names and symptoms mentioned. We focused on a certain disease name, namely, Shnaghan(傷寒; injured by cold), which is the main subject of Shangha-lun(傷寒論). Looking closely into these Juan Wooden Slips, we found many articles recording Shanghan, including related diseases and symptoms, such as Shanghan(傷汗; injured by sweat), headache, fever and chills, immobilization of limbs, unacceptance of foods. And there are another Shanghan-related symptoms, such as inflation of upper-abdomen(心腹支滿), pain of upper abdomen(心腹痛), strain of both armpits(兩胠葥急), inflation of chest(胸脇支滿), tightness and fear in the chest(煩滿). Although they have no direct relationship with Shanghan, there are many symptoms, including the external wounds of waist, finger, thigh, back, breast and head, abscess of leg and elbow, sore throat, itching, leucorrhea, powerlessness of hands and legs(手足癃), visceral injury(傷臟), tinnitus, cold, warm and heat. Because the Wooden Slips are very short, with some characters even missing, we can not confirm the detail of the disease and symptoms. In addition, we will report about the herbal medicines and other treatments, which are recorded on the slips, by further research.

• Journal of the Institute of Convergence Signal Processing
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• v.17 no.2
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• pp.71-76
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• 2016

Digital image processing is being utilized in various fields including medical industry, satellite photos, and factory automation image recognition. However, this kind of image data produces heat by an external cause in the course of being processed, transmitted, and stored. Most typical noises added in the images are AWGN and salt and pepper. MF, CWMF, and AWMF are methods used to restore images damaged by AWGN and the existing methods are likely to damage detailed information such as an edge. Therefore, this paper suggests an algorithm applying weight of average filter, average filter depending on pixel, and spatial weight filter based on edge size of local mask in an AWGN environment, in a different way. Also, this paper compares functions of existing methods by using PSNR to prove excellence of the suggested algorithm.

• Nuclear Engineering and Technology
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• v.48 no.2
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• pp.457-469
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• 2016

During the late phase of severe accidents of light water reactors, a porous debris bed is expected to develop on the bottom of the flooded reactor cavity after breakup of the melt in water. The geometrical configuration, i.e., internal and external characteristics, of the debris bed is significant for the adequate assessment of the coolability of the relocated corium. The internal structure of a debris bed was investigated experimentally using the DAVINCI (Debris bed research Apparatus for Validation of the bubble-Induced Natural Convection effect Issue) test facility. Particle sedimentation under the influence of a two-phase natural convection flow due to the decay heat in the debris bed was simulated by dropping various sizes of particles into a water vessel with air bubble injection from the bottom. Settled particles were collected and sieved to obtain the particle mass, size distribution in the radial and axial positions, and the bed porosity and permeability. The experimental results showed that the center part of the particle bed tended to have larger particles than the peripheral area. For the axial distribution, the lower layer had a higher fraction of larger particles. As the sedimentation progressed, the size distribution in the upper layers can shift to larger sizes because of the higher vapor generation rate and stronger flow intensity.

• The Journal of Pediatrics of Korean Medicine
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• v.21 no.3
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• pp.189-203
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• 2007

Objectives The prognosis, recurrence rate and treatment of febrile seizure were studied through the research of recent western medicine and Chinese oriental medicine paper. Methods Recent western medicine paper of internal and external and chinese oriental medicine paper from 1999 to 2007 were investigated. Results and Conclusions The prognosis of febrile seizure was good in most cases, but children with febrile seizure who developed epilepsy range between 2 and 10%. The risk factors developed epilepsy including complex febrile seizure, focal and prolonged seizure, pre-existing neurodevelopmental abnormalities and recurrent febrile seizure. Recurrence rate of febrile seizure ranges between 30 and 50% was high. The risk factors can be predicted by their age at first febrile seizure happened, family medical history of febrile seizure and epilepsy, complex febrile seizure, and neurodevelopmental abnormalities. However, the most important factor of those is the age when they have first febrile seizure. Diazepam or Lorazepam was administrated for a child with prolonged seizure but only Diazepam was used for reducing recurrence of febrile seizurein febrile illness. However, there were some side effects such as lethargy, ataxia, and irritability. The study of chinese oriental medicine demonstrates that the acupuncture and venesection were used for seizure attack and reduced of recurrences and second attack. To reduce recurrence of febrile seizure, herbal medicine was also used for febrile illness or after seizure attack within a certain period of time, so reduce the recurrence, frequency of seizure and febrile illness. The most of herbs in prescription were used for removing heat and toxic meterials(淸熱解毒), extinguishing wind and to stopping the convulsion(熄風止痙)

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.32 no.4
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• pp.101-115
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• 2019

Objectives : The purpose of this study is to analyze the use of herbal medicine as a treatment method in the case studies on warts in Korea, to identify trends in herbal medicines and herbal prescriptions according to the characteristics of individual patients and to systematically analyze concurrent therapies. Methods : Domestic databases (OASIS, RISS, NDSL, KTKP, KISS, KISTI, KISTI) were used to search for case studies related to the herbal medicine treatment of warts. There was no restriction on the time of publication. A total of 9 papers were selected. Results : A total of 13 prescriptions were presented 23 times in 18 cases. Among them, bojungikgi-tang gamibang(補中益氣湯加減方) was the most frequently prescribed. Gwakhyangjeonggi-san gamibang(藿香正氣散加減方) and Damsoeun-tang gagam were the next most frequently prescribed. 69 herbs were used in a total of 13 prescriptions. Herbs were commonly classified as heat-clearing medicine(淸熱藥), exterior-releasing medicine(解表藥), and tonifying and replenishing medicine(補益藥) in descending order. The herbs used more than 6 times included Coicis Semen(薏苡仁), Glycyrrhizae Radix et Rhizoma(甘草) (10 times), Bupleuri Radix(柴胡), and Scutellariae Radix(黃芩) (6 times). Concurrent therapies were performed except for 1 study, and they were acupuncture, moxibustion, pharmacopuncture, external agents, and cupping therapy. Conclusions : This is the first study to analyze the use of herbal medicine as a treatment method for warts in case studies performed in Korea. We hope that this study would give helpful information about the treatment of warts in clinical practices.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.115-121
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• 2008

A core engine for pre-cooled turbojet engines is designed and its component performances are examined both by CFD analyses and experiments. The engine is designed for a flight demonstration of precooled turbojet engine cycle. The engine uses gas hydrogen as fuel. The external boundary including measurement devices is set within $23cm{\times}23cm$ of rectangular cross section, in order to install the engine downstream of the air intake. The rotation speed is 80000 rpm at design point. Mixed flow compressor is selected to attain high pressure ratio and small diameter by single stage. Reverse type main combustor is selected to reduce the engine diameter and the rotating shaft length. The temperature at main combustor is determined by the temperature limit of non-cooled turbine. High loading turbine is designed to attain high pressure ratio by single stage. The firing test of the core engine is conducted using components of small pre-cooled turbojet engine. Gas hydrogen is injected into the main burner and hot gas is generated to drive the turbine. Air flow rate of the compressor can be modulated by a variable geometry exhaust nozzle, which is connected downstream of the core engine. As a result, 75% rotation speed is attained without hazardous vibration and heat damage. Aerodynamic performances of both compressor and turbine are obtained and evaluated independently.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.6
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• pp.1-8
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• 2021

The performance of hidden camera cameras is improving day by day due to miniaturization and advanced technology integration according to the speed of technological development of smartphones. As this external networking computing environment is advanced and diversified, exposure to hidden cameras in addition to general safety cameras is also increasing. On the other hand, the technology for detecting and preventing hidden cameras is not keeping up with the development and speed of these hidden cameras. Therefore, in this study, the heat of the hidden camera was detected using infrared thermal detection technology based on general image and thermal image synthesis technology, and the reflectance of each wavelength according to the difference in ambient temperature was analyzed to reduce the false positive rate.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.4
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• pp.303-311
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• 2019

Reversible solid oxide fuel cell (RSOFC) has become a prospective device for energy storage and hydrogen production. Many studies have been conducted around the world focusing on system efficiency improvement and realization. The system should have not only high efficiency but also a certain level of simplicity for stable operation. External waste steam utilization was proved to remarkably increase the efficiency at solid oxide electrolysis system. In this study, RSOFC system coupled with waste steam was proposed and optimized in term of simplicity and efficiency. Ejector for fuel recirculation is selected due to its simple design and high stability. Three system configurations using ejector for fuel recirculation were investigated for performance of design condition. In parametric study, the system efficiencies at different current density were analyzed. The system configurations were simulated using validated lumped model in EBSILON(R) program. The system components, balance of plants, were designed to work in both electrolysis and fuel cell modes, and their off-design characteristics were taken into account. The base case calculation shows that, the system with suction pump results in slightly lower efficiency but stack can be operated more stable with same inlet pressure of fuel and air electrode.