• Title/Summary/Keyword: Blended study

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A Exploratory Study on Educational Effects of VET Teacher Certificate E-learning Program (직업훈련교사 자격연수과정의 블랜디드 교육효과 탐색)

  • Suk, Hwang
    • The Journal of Korean Institute for Practical Engineering Education
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    • v.4 no.2
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    • pp.67-74
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    • 2012
  • This study elicits alternatives for improving blended education by comparing the face-to-face education and blended education of VET teacher license program. To produce a basis for the methods of blended education, this study compared the scores of satisfaction and academic performance of face-to-face and of blended education. Also it examined the three factors of learners' characteristics, teaching and learning design, and its environment as they affect the education effect. The results showed that academic performance of face-to-face education is higher than blended and that competition rate of blended education is higher than that of face-to-face. To improve the effect of blended learning, various teaching and learning activities, design of contents that promotes participation and interaction, and development of contents which satisfy the various levels of learning needs were discussed.

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A Study on the One Bath One Step Thermosol Dyeing of Polyester/Cotton Blended Fabrics (폴리에스터/면 혼방직물의 1욕 1단 서모졸 염색에 관한 연구)

  • Ro, Duck-Kil
    • Textile Coloration and Finishing
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    • v.20 no.1
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    • pp.16-21
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    • 2008
  • In this study the effects of swelling and fixing agent for the cotton side of polyester/cotton blended fabrics and the thermosol temperature on the dyeing properties and fastness. were investigated, when the polyester/cotton blended fabrics were dyed with a disperse dye which was able to dye both side of fiber by one bath one step thermosol process. The obtained results are as follows; The dye adsorption decreased with the increase of cotton blend ratio in polyester/cotton blended fabrics, when the ratio of swelling and fixing agent for cotton side was constant. As the thermosol temperature increased up to $210^{\circ}C$, the dye adsorption were increased, but that effect was less significant when the cotton blend ratio was higher.

A Study on Performance and Exhaust Emissions of DI Diesel Engine Operated with Neat DME and DME Blended Fuels (순수 DME 및 DME 혼합연료의 직접분사식 디젤기관의 성능 및 배기가스 특성에 관한 연구)

  • 표영덕;김강출;이영재;김문헌
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.2
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    • pp.75-82
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    • 2003
  • DME is a good alternative fuel to reduce the smoke remarkably when used in a diesel engine, while problems concerned with low lubricity and high compressibility exist. In the present study, single cylinder DI diesel engine was operated with neat DME and DME blended fuels which are DME-diesel blended fuel and DME-propane blended fuel. The results showed that the power of the neat DME and DME blended fuels was the same as that of pure diesel oil, and the specific energy consumption slightly increased. In addition, smoke emission was considerably reduced with the increase of DME content up to zero level, but NOx emission was slightly increased.

Experimental Study on the Application Characteristics of Bio-diesel blended Fuel by Ultrasonic Irradiation in CRDI type Diesel Engine (CRDI 방식 디젤기관의 초음파 조사 Bio-diesel 혼합연료 적용 특성에 관한 실험 연구)

  • Jung, Y.C.;Im, S.K.;Park, S.Y.;Choi, D.S.;Ryu, J.I.
    • Journal of ILASS-Korea
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    • v.12 no.3
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    • pp.131-137
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    • 2007
  • This is an experimental study on characteristics of engine performance and discharged materials in common-rail type diesel engine. The bio-diesel fuel is mixed with the diesel fuel in common use at the ratio of 20% or 100%. The diesel fuel and blended fuel is irradiated by ultrasonic wave energy. The diese1 fuel, blended fuel, reformed diesel fuel and reformed blended fuel by ultrasonic wave energy are applied to the experimental engine individually. The results are compared with one of the diesel fuel in common use and analyzed.

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A Study on Combustion and Emission Characteristics of the Methanol Blended Fuel in SI Engine (SI엔진의 메탄올 혼합 연료의 연소 및 배출 가스 특성에 관한 연구)

  • 조행묵;이창식
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.6
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    • pp.1-6
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    • 2003
  • The engine performance and combustion characteristics of methanol blended fuel in a multiple-point electronic control gasoline engine were discussed on the basis of experimental investigation. The effects of methanol blending fuel on combustion in cylinder were investigated under various conditions of engine cycle and blending ratio. The results showed that the engine performance was influenced by the methanol blended ratio. The results showed that the engine performance was influenced by the methanol blending ratio and the variations of operating conditions of test engine. The increase of blended fuel brought on the improvement of emission characteristics such as THC, CO, and NOx concentration. The effect of methanol blended fuel on the fuel consumption rate and the other characteristics of performance were discussed.

Studies on Therapeutic range, Symptom, Pathology, and composition of Polygala tenuifolia-main blended Prescriptions from Donguibogam (동의보감(東醫寶鑑)에 수록된 원지(遠志)가 주약(主藥)으로 배오(配伍)된 처방(處方)의 방제학적(方劑學的) 고찰(考察))

  • Kim Young-Bok;Yun Young-Gab
    • Herbal Formula Science
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    • v.10 no.1
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    • pp.33-39
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    • 2002
  • There are total 33 prescriptions containing Polygala tenuifolia as a principal medicine in Donguibogam. This report describes the studies on therapeutic range, symptom, pathology and composition of 33 Polygala tenuifolia-main blended Prescriptions from Donguibogam. The percentage of Polygala tenuifolia-main blended prescriptions for the therapeutic range are as follows: psychopathy is the most frequent(54.4%) and eczema, purulent inflammation is second(21%) and feebleness is third(15%). The main pathologies of Polygala tenuifolia-main blended prescriptions are associated with heart, kidney and stomach. The main combinations of Polygala tenuifolia-main blended prescriptions in psychopathy are Jeongji-hwan and Chongmyung-tang.

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Study on the Properties of the Low Heat Concrete Applied to the Mass Concrete by the Blended Cements (혼합시멘트를 사용한 저발열콘크리트의 매스콘크리트 적용을 위한 기초특성 연구)

  • Lee, Jin-Woo;Lee, Young-Hwan;Kim, Kyung-Min;Bae, Yeoun-Ki;Lee, Jae-Sam
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.641-644
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    • 2006
  • Considering properties of the low-heat concrete mixed with the blended cements, the influences compared blended cements with ordinary portland cement made experiments on. (1) Blended cements were superior to OPC in the fresh concrete flow that the use of blended cements reduced chemical admixture. (2) The more the use of additive increase, the more bleeding happens. So it is considered to heights, order, and rate of placement, curing methods and so on. (3) The use of blended cements increase long term strength after 28 days, but decrease early strength and durability. So it is considered to the curing methods and early frost damage, and endurance limit.

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A study on combustion of blended straight vegetable oil in marine diesel engine cylinders

  • Nguyen, Dai An;Tran, The Nam;Dang, Van Uy
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.8
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    • pp.813-820
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    • 2015
  • Straight vegetable oil (SVO) is widely recommended as fuel for diesel engines in general and especially for marine diesel engines. However, SVOs used directly as fuel for diesel engines may cause problems for the engines; SVOs blended with diesel oil are a better choice. To widen understanding of the possibility of using blended SVOs as fuel alternatives, this paper presents results of experimental research on the combustion of blended straight vegetable oil in a marine diesel engine's cylinders. Results show that the fuel combustion process have the same curves as in simulations and, in the case of using blended fuels with up to 20% palm oil, the test diesel engine technical parameters such as engine output, exhaust gas temperatures, and specific fuel consumption are very similar to those of diesel oil (DO). Based on these results, marine diesel engines are strong potential applications and particularly recommended for the use of SVO blends.

Physical Properties of Ultrafine Ash Blended Cement (초미분말 애시를 혼합한 시멘트의 물성)

  • Yoo, Dong-Woo;Byun, Seung-Ho;Song, Jong-Taek
    • Journal of the Korean Ceramic Society
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    • v.44 no.9
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    • pp.489-495
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    • 2007
  • Effects of ultrafinely ground ash on the rheological properties of cement paste were investigated. Also compressive strength development and setting time of ultrafine ash blended cement mortar were investigated in the study. A sample with silica fume was included for comparison. According to the results of ultra fine ash blended cement paste in the lower W/B ratio, the fluidity were high, and the setting time was a little retarded. And the compressive strength of ultrafine ash blended mortar was increased in the long term. In the case of hardened cement paste at 28 days, $Ca(OH)_2$ contents was decreased in order of control, ultrafine ash, silica fume blended cement due to difference of the pozzolanic reaction.

Application of Mass Concrete Exposed to Marine Environment (염해환경에 노출된 매스콘크리트의 시공)

  • Kim Dong Seok;Park Sang Joon;Shin Hong Chol;Yoo Jae Kang
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05a
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    • pp.487-490
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    • 2005
  • This study was performed to investigate the effect of ternary blended cement concrete mixed with slag cement and fly ash on the compressive strength, the resistance to chloride ion penetration and reduction of hydration heat. Each performance of ternary blended cement concrete compared with binary blended cement concrete and ordinary portland cement concrete. As a result, it was concluded that ternary blended cement concrete is suitable to mass concrete under marine environment.

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