• Journal of the Korea Convergence Society
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• v.11 no.2
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• pp.155-160
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• 2020

In this study, the pleasant driving environment of the driver and passenger in the summer was investigated through the internal flow analysis of air due to the opening and closing of the car windows. The conditions on the entrance of the air conditioner with the opening and closing status of vehicle window were applied to the flow analysis by taking into consideration the actual driving environment. The automotive air conditioning outlet, the seat and the inside of car were modeled. As the air flow inside the car was analyzed, the air flow configuration and the temperature distribution were examined. In this analysis, the results were taken in consideration of only the effects of internal air and the opening and closing of window, assuming the interior of the vehicle as insulation. The analysis of each condition shows that these models maintain a pleasant environment. It is seen that this analysis result on the internal flow analysis according to the opening and closing of vehicle window can be applied by converging with the field of design.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.312-312
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• 2010

모터나 기계류와 같이 주변에서 발생하는 미활용 진동에너지를 전기에너지로 수확하기 위한 Piezoelectric Energy Harvester를 개발하고자 하였다. PZT-5H의 조성으로 후막세라믹 적층 구조 캔틸레버 타입의 압전시트를 통해 압전 에너지 하베스터를 제작하였다. 일반적으로 진동에너지를 수확하여 전기에너지로 변환시키는 압전 에너지 하베스팅 기술은 에너지 효율이 낮은 문제점을 가지고 있으므로 에너지 효율을 높이기 위한 방법으로 본 연구에서는 Unimorph 와 Bimorph 타입의 캔틸레버의 가로, 세로, 두께, 재료변수에 따라 발생하는 최적의 효율을 가지는 구조를 찾고자 하였다. 캔틸레버 각 변수에 따른 공진주파수 대역에서 발생하는 전압을 분석하여 50Hz의 공진주파수를 가지는 60*35*0.2mm의 캔틸레버를 설계하였다. 시뮬레이션을 통해 얻어진 결과를 실험적으로 검증하기 위해 전력량을 측정한 결과, Bimorph는 Unimorph 타입에 비해 2배가량의 향상된 발전특성을 가지며 에너지 하베스터에서 초당 $76.2\;{\mu}W$의 전력량을 가지는 것을 확인하였고 시뮬레이션 결과와의 타당성을 확인하였다.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.43 no.4 s.310
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• pp.31-38
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• 2006

In this paper, the inputting method of english pronunciation for a computer by the combining diacritical mark is studied. English pronunciation system and the methods of its notations are investigated and conditions to input english pronunciations easily are analysed. Therefore, the inputting method which can input 3, 4-level stress as well as 2-level stress is presented. By using this method, English pronunciation can be inputted to the spreadsheets, databases and presentations as well as word-processors, and each application program's data can have compatibility. In the result of experiments, every data can have the compatibility in all of application programs and inputting speed is increased highly compare with using the individual vowel method which has high speed than using the pre-existing functions of word processors.

• Korean Journal of Environment and Ecology
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• v.15 no.2
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• pp.173-185
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• 2001

마편초과의 좀목형 엽에 함유된 물질의 allelopathy 효과를 구명하기 위해 수용성 엽 추출액, 메탄올 엽 추출액, 엽 분말과 토양과의 혼화된 pot에 각각 상치, 이탈이란라이그라스, 개솔새, 억새 종자를 발아실험하여 발아억제물질을 분석한 결과는다음과 같다. 1. 좀목형 엽 분말을 증류수에 각각 24, 48, 72 시간 침지 후 추출물에 상치, 이탈리안라이그라스, 개솔개, 억새 종자를 파종한 후의 발아율은 각 처리구마다 대조구마다 높은 발아억제를 보였고, 48시간 침지시에는 각각 26.9%, 58.8%, 6.6%, 22.2%의 발아율을 보여 강한 발아억제현상르 보였다. 2. 좀목형 엽 분말을 메탄올 75%에 24, 48시간 침지 후 추출물에 이탈리아라이그사스, 개솔새, 억새 종자를 파종한 후의 발아율은 48시간 추출액때 각각 33.3%, 15.4%, 7.7%를 보여 48시간 수용성 추출액과 24시간 메탄올 추출액보다 강한 발아억제효과가 있었다. 3. 좀목형 엽 분말과 Vermiculite를 1: 99.5: 95, 10:90, 20:80(w/w)으로 구분한 pot에 공시수종을 파종한 결과 엽 분말의 비율이 높을수록 발아억제효과가 컸으며, 엽 분말이 20%인 경우 발아된 부분의 건중량의 비율은 실험구와 대조구간에 비교한 발아율의 비율보다 훨씬 낮아 생장억제효과가 있는 것으로 나타났다. 4. Column chromatography의 TLC를 이용하여 최종 7 fraction을 찾고 생물검정 결과, 5, 6번 fraction에 강한 활성을 나타냈다. 5. UV 와 IR분광분석 결과 UV 분광분석은 256 nm과 336nm에서 흡수 최대를 나타내었으며, 이들은 시르시트시약을 사용하여 검토한 결과 7위에 에테르 결합한 전형적인 플라본류로 추정되었고, IR 분광분석 결과 지방족에 에테르결합이 존재하는 것으로 생각되었다. 6. Py-GC-MS 분석으로부터 5, 6 fraction의 경우 플라본류에 1개의 당이 결합한 배당체 구조이고 B환의 경우 1개 또는 2개 이상의 페놀성 수산기의 존재가 예상되었다.

• International Journal of Highway Engineering
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• v.4 no.3 s.13
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• pp.15-23
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• 2002

The waterproofing system's performance is known to show a determing by complex interaction of material factors, design details, and the quality of construction, and the waterproofing integrity of waterproofing membranes is determined by the bond to the deck and the amount of damage to the waterproofing membrane. In this research, the basic properties of waterproofing membranes on market and the tensile adhesive chracteristics of waterproofing systems of concrete bridge deck have also been investigated in the view of the damages frequently reported from job site. For the tensile adhesive strength of sheet waterproofing membranes, the results after asphalt concrete paving tends to increase more than before those. The results of the liquid waterproofing membranes are upside-down, and the more concrete has strength, the more strength of tensile adhesive increase. The ambient temperature of asphalt concrete when application of the waterproofing membrane has considerable influence on the performance of waterproofing system. As described above, waterproofing system can be influenced by several factors. If they are not considered under construction, the overlooking will cause the damages of pavement and waterproofing system after traffic opening.

• Journal of Digital Contents Society
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• v.18 no.3
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• pp.607-612
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• 2017

The use of RaspberryPi in building an embedded system may be difficult for users in understanding the circuit and the hardware cost. This paper proposes a solution that can test the systems virtually. The solution consists of three elements; (i) editor, (ii) interpreter and (iii) simulator and provides nine full modules and also allows the users to configure/run/test their own circuits like real environment. The task of abstraction for modules through the actual circuit test was carried out on the basis of the data sheet and the specification provided by the manufacturer. If we can improve the level of quality of our solution, it can be useful in terms of cost reduction and easy learning. To achieve this end, the electrical physics engine, the level of interpreter that can be ported to the actual board, and a generalization of the simulation logic are required.

• Resources Recycling
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• v.21 no.6
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• pp.23-31
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• 2012

Removal work about weeds that grow naturally on road and industrial complex is attaining ordinary times but is suffering difficulty in weeding work by strong self-generation power. In the meantime, going side by side with these manual processing and weeding work through construction of weed-proof seat is attaining, but economic performance, limitation of application region and withdrawal processing problem are being blamed for shortcoming. The scope of this study is about the manufacture of weed-proof mortar using eco-friendly industrial byproducts characterized by an economic and simplicity for not limited to loss of function as a product recovered after treatment. After the carried out the various experiments and actual construction for the selection of mixing materials and derivation of appropriate mix, through the comparison and analysis of results, it was investigated the research results of weed-proof mortar for fundamental development.

• Journal of Bio-Environment Control
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• v.9 no.2
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• pp.79-84
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• 2000

The growth and quality differences between common thyme(Thymus vulgaris L.) and lemon thym (Thymus$\times$citriodorus) were investigated. They were grown in a hydroponics culture system (DFT) with a nutrient solution developed by the European Vegetable R&D Center in Belgium. Nutrient solution ionic strength used were 1.2, 2.4, 4.8 and 7.2 mS.cm-1. The dry matter of two thymes were increased with increasing ionic strength, while shoot length, root length and fresh weight were decreased. Chlorophyll content was higher in lemon thyme, while vitamin C content and essential oil content were higher in common thyme. The essential oil content showed a similar trend as those of growth. The main compostion of essential oil were thymol and carvacrol in common thyme, and geraniol and $\alpha$-citral in lemon thyme. The highest content of these compounds was obtained in 1.2mS.cm-1 treatment. Consequently, the ionic strength of 1.2mS.cm-1 was suitable for the production of quality thymes.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.124-132
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• 2019

Water-repellent coating solutions were synthesized by hydrolysis and polycondensation reactions with water using tetraethoxysilane (TEOS) and chlorotrimethylsilane (CTMS) as precursors. The solutions were coated on a PMMA sheet and thermally cured to prepare non-fluorinated water-repellent coating films. Coating films were characterized by water contact angles, UV-Vis transmittance and surface morphology. The contact angle of coating films prepared by varying the molar ratio of CTMS/TEOS to 0.6~1.0 exhibited a maximum value of $107^{\circ}$ when the CTMS/TEOS molar ratio was 0.8. The coating films showed a high transmittance over the visible range up to 90% when the CTMS/TEOS molar ratios were 0.6~0.8. However, when the molar ratios of CTMS/TEOS were 0.9~1.0, the transmittance of coating films was lower than 70% due to an uneven shape of the rough surface.

• Journal of the Korea Society of Computer and Information
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• v.26 no.1
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• pp.37-44
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• 2021

This study is to design and to develop the educational contents to enhance artificial intelligence literacy. First, we designed artificial intelligence education contents and constructed education programs. The contents are composed of a total of 15 lectures in 8 AI domains. The contents contain the elements of knowledge-skill-attitude, and 5 learning steps. The developed contents were organized in the form of online materials and included simulations and worksheets to directly manipulate and explore the concepts and algorithms of AI. In addition, we provided evaluation questions for each content. To examine the suitability of content, we conducted a validity test for experts. As a result of the content validity test, the overall average was .71 or higher, and the CVI value of the class suitability was .82, indicating a high validity. We are expected to use the contents developed in this study as an effective program to improve AI literacy in university liberal arts education.