• Korean Journal of Optics and Photonics
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• v.19 no.1
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• pp.9-14
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• 2008

In this paper, a new type of Yagi-Uda antenna that operates in the terahertz frequencies is designed. The proposed Yagi-Uda antenna can obtain high input resistance of approximately $2000{\Omega}$ at the resonance frequency by using a full-wavelength dipole instead of a half-wavelength dipole as the driver element. The current leakage into the bias line was minimized by applying the photonic bandgap structure to the bias line. By designing the antenna on a thin substrate, the impedance lowering of an antenna caused by the relative dielectric constant of the substrate was prevented and the end-fire radiation pattern which is the original radiation characteristic of the Yagi-Uda antenna could be obtained. We expect that the proposed Yagi-Uda antenna can achieve increased terahertz output power by improving the impedance mismatching problem with the photomixer.

• Journal of Korean Medicine Rehabilitation
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• v.25 no.1
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• pp.53-61
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• 2015

Objectives The purpose of this study is to compare the common herbs for pain related disease between Yak-Jing and textbook of herbology. Methods We searched the formation of "Koho" and theory of Todo yoshimasu. We selected the common herbs that is used for pain related disease in Yak-Jing and textbook of herbology. These herbs were compared with each other. Result 1. Common Herbs for pain related disease are Ephedrae Herba (麻黃), Aconiti Lateralis Preparata Radix (附子), Euphorbiae Kansui Radix (甘遂), Euphorbiae pekinensis Radix (大戟) Daphnis Genkwa Flos (芫花), Atractylodis Rhizoma (朮), Paeonia Radix Rubra (芍藥), JujubaeFructus (大棗), Gypsum (石膏), Anemarrhenae Rhizoma (知母), Cinnamomi Ramulus (桂枝), Poria (茯苓), Rhei Rhizoma (大黃), Natrii Sulfas (芒草), Pueraiae Radix (葛根). There are some difference between textbook of herbology and Yak-Jing about Aconiti Lateralis Preparata Radix (附子), Paeonia Radix Rubra (芍藥), Atractylodis Rhizoma (蒼朮), Pueraiae Radix (葛根). 2. Preparata Radix (附子) excrete water poisons (水毒) in Yak-Jing, but it has the effect of restore yang and tonify fire (回陽補火) in textbook of herbology. 3. Paeonia Radix Rubra (芍藥) is effective for pathological condition caused by the formation of the band and spasm (結實拘攣) in Yak-Jing, but it is to cure heat pattern in textbook of herbology. 4. Atractylodis Rhizoma (蒼朮) has the effect of water-draining (利水) in Yak-Jing, but it has the effect of dispersing (發散) in textbook of herbology. 5. Pueraiae Radix (葛根) is used in dyspnea and sweating (喘而汗出) in Yak-Jing, but it is to cure engender fluid (生津), skin disease, diarrhea in textbook of herbology. Conclusion There are some difference between textbook of herbology and Yak-Jing in the herb medicine that is used in pain related disease.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.5
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• pp.60-69
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• 2013

An optimum configuration of the hybrid/dual swirl jet combustor for a micro-gas turbine was investigated experimentally. Location of pilot nozzle, angle and direction of swirler vane were varied systematically as main parameters under the conditions of constant thermal load. The results showed that the variation in locations of inner fuel nozzle and pilot burner resulted in significant change in flame shape and swirl intensity due to the changes in recirculating flow pattern and minimum flow area near burner exit, in particular, with the significant reduction of CO emission near lean-flammability limit. In addition, it was observed that the co-swirl configuration produced less CO and NOx emissions compared to the counter-swirl configuration.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.2
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• pp.465-472
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• 2016

Principal Component Analysis (PCA) is useful statistical technique for finding patterns in data, and expressing the data in such a way as to highlight their similarities and differences. In this paper, 1417 marine casualties occurred in Korean littoral sea in recent 5 years, were examined by the PCA. The main results obtained were as follows : 1. Most of marine casualties resulted from the human factors such as careless operation and insufficient engine maintenance. 2. Collision and standing mainly resulted from steering room-related human factors such as careless guard, inadequate ship-handling, however engine damage and fire explosion mainly resulted from engine room-related human factor such as bad handling of engine system. 3. No. 1 principal component represents accident frequency, No. 2 principal component represents the cause and No. 3 principal component represents the pattern of marine casualties, respectively.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.5
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• pp.987-994
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• 2018

In this paper, an automatic transmission system of traffic information is presented. Here, a traffic event is defined as an obstacle to an emergency vehicle such as an ambulance or a fire truck. When a traffic event is detected from a video recorded by a black box installed in a vehicle, the implemented system automatically transmits a proof image and corresponding information to the control center through an e-mail. For this purpose, we realize an algorithm of identifying the numbers and a character from the license plate, and an algorithm for determining the occurrence of a traffic event. To report the event, a function for automatic transmission of the text and image files through e-mail and file transfer protocol (FTP) is also appended. Therefore, if the traffic event is extended and applied to the presented system, it will be possible to establish a convenient reporting system for the violation of various traffic regulations. In addition, it will contribute to significantly reduce the number of traffic violations against the regulations.

• Journal of Environmental Impact Assessment
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• v.20 no.3
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• pp.337-348
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• 2011

Urban environmental problem became one of major issues during its urbanization processes. Environmental impacts are assessed during recent urban planning and development. Though the environmental impact assessment considers meteorological impact as a minor component, changes in wind environment during development can largely affect the distribution pattern of air temperature, humidity, and pollutants. Impact assessment of local wind is, therefore, a major element for impact assessment prior to any other meteorological impact assessment. Computational Fluid Dynamics (CFD) models are utilized in various fields such as in wind field assessment during a construction of a new building and in post analysis of a fire event over a mountain. CFD models require specially formatted input data and produce specific output files, which can be analyzed using special programs. CFD's huge requirement in computing power is another hurdle in practical use. In this study, a CFD model and related software processors were automated and integrated as a microscale wind environmental impact assessment system. A supercomputer system was used to reduce the running hours of the model. Input data processor ingests development plans in CAD or GIS formatted files and produces input data files for the CFD model. Output data processor produces various analytical graphs upon user requests. The system was used in assessing the impacts of a new building near an observatory on wind fields and showed the changes by the construction visually and quantitatively. The microscale wind assessment system will evolve, of course, incorporating new improvement of the models and processors. Nevertheless the framework suggested here can be utilized as a basic system for the assessment.

• Journal of the Society of Disaster Information
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• v.15 no.2
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• pp.214-222
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• 2019

Purpose: The purpose of this study is to develop a sprinkler head that can be controlled and initial suppressed by installing it in a rack-type warehouse. Method: Considering the spray radius and spray pattern, various deflectors were designed, and the spray angle, discharge characteristics and protection performance test was conducted, and these results were compared and analyzed. Results: An optimal sprinkler head was developed to protect full load, front side of a commodity with minimum water volume 115L/min. Conclusion: The developed head of K-115 and 1Bar pressure was tested with one tier storage confirming that the fire control is carried out without burning all the loadings. In addition, the vertical distance from the top of the load to the deflector shall be separated by 450mm and installed to allow sufficient discharge to the outer part of the commodity.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.293-296
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• 2016

In case of an emergency on a busy road of a city, drivers should make way for special vehicles such as police cars, fire engines, or ambulance as soon as possible. If road infrastructures recognize the movements of special vehicles, and transfer alert message to traffic signal controllers and normal cars through wireless network such as WAVE or TPEG, normal cars can prepare to make way in advance. As a result, it help special vehicles move faster. In this paper, we install a roof mark on the roof of a special vehicle, detect the mark through a mark recognition algorithm which includes perspective transformation, and get the inner information by decoding the digital pattern on it. The experiment results show that mark can be recognized 100% and 93.3% of inner digital data of the mark can be recognized, when the size of a mark is larger than $88cm{\times}88cm$ and the mark moves at a speed of 50km/s.

• Fashion & Textile Research Journal
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• v.23 no.1
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• pp.118-128
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• 2021

This study used a preliminary survey to help develop an ergonomic flight jacket that is suitable for the working environment and mission performance. The results are as follows. The ergonomic sleeve pattern was designed with a forward 165° incline that considers a shoulder joint direction suitable for the motion; in addition, a closely design opening provided warmth and safety from fire. As a result of the dimensional suitability, pilots evaluated that sleeve length and total length of the developed flight jacket were a little long (p<.01), while flight engineers and crew evaluated that those of the developed flight jacket were appropriate (p<.01). Pilots evaluated that chest circumference and waist circumference were large (p<.05), while flight engineers and crews evaluated that those of the developed flight jacket were appropriate. The evaluation of the motion suitability indicated that pilots, flight engineers and crew found the developed flight jacket more comfortable than the current flight jacket (p<.05, p<.01, p<.001). The evaluation of the usability of pockets and penholders indicated that pilots, flight engineers and crew found the developed jacket easier to use (p<.01). The flight engineers and crew evaluated that the appearance of the developed flight jacket was better than the current flight jacket (p<.05). The results of this study show that the difference of environment and mission performance has a significant influence on evaluation; therefore, it is necessary to develop separate military uniforms that included a winter flight jacket to reflect the needs of each group.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.35 no.3
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• pp.1-14
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• 2022

Background : Tinnitus is common disorder with many possible causes and a symptom of many different diseases but has no effective treatment. Most of tinnitus patients experience the disorder to a degree that their quality of life and productivity are impaired. Especially tinnitus accompanied hearing loss causes severe discomfort in patients. Objectives : 1. Through symptoms of tinnitus, we tried to find out the relationship of Heo-sil(虛實) and Zuang fu bian zheng(臟腑辨證) among tinnitus patients accompanied Hearing Loss. 2. By testing THI, we tried to evaluate the quality of life of tinnitus patients group and tried to compare the quality of life between high-narrow tone and low-wide tone tinnitus patients group. 3. In the future, this study was planned to help monitor the prognosis and determine the progress of treatment for tinnitus patients who also have hearing loss. Methods : 43 patients were recruited in this study who was ill with tinnitus accompanied hearing loss. They wrote out the questionnaire about tinnitus and the Tinnitus Handicap Inventory(THI). Results : 1. In tinnitus patients, there were more men than women accompanied hearing loss. The rate of visits was higher as the age increased. 2. Most of the patients who visited the hospital had sensitive hearing loss. 3. In high-narrow tone tinnitus group, phlegm fire congesting-type are more uncomfortable than spleen-stomach weakness-type. 4. In low-wide tone tinnitus group, liver qi depression was the most uncomfortable. Conclusions : The present study suggests that tinnitus pattern may be helpful in differentiating patients with tinnitus, and the effectiveness of treatment can be predicted through differentiation. Zuang fu bian zheng(臟腑辨證) and Distinguishing between Heo(虛) and Sil(實) is expected to have positive effects on tinnitus accompanied hearing loss treatment.