• Advances in concrete construction
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• v.5 no.3
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• pp.289-301
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• 2017

The synergistic interactions of supplementary cementitious materials (SCMs) with ordinary portland cement (OPC) in multi-blended systems could enhance the mechanical and durability properties of concrete and increase the amount of cement that can be replaced. In this study, the characteristics of the hydration products as well as paste microstructure of blended cement containing 20% coal fly ash, 10% rice hull ash and 10% sugar mill lime sludge in quaternary blended system was investigated. Portlandite content, hydration products, compressive strength, pore size distribution and microstructural architecture of hydrated blended cement pastes were examined. The quaternary blended cement paste showed lower compressive strength, reduced amount of Portlandite phases, and higher porosity compared to plain hardened cement paste. The interaction of SCMs with OPC influenced the hydration products, resulting to the formation of ettringite and monocarboaluminate phases. The blended cement paste also showed extensive calcium silicate hydrates and calcium aluminate silicate hydrates but unrefined compared to plain cement paste. In overall, the expected synergistic reaction was significantly hindered due to the low quality of supplementary cementitious materials used. Hence, pre-treatments of SCMs must be considered to enhance their reactivity as good quality SCMs can become limited in the future.

• Advances in environmental research
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• v.4 no.3
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• pp.197-210
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• 2015

Hexavalent chromium [Cr (VI)] adsorption on lateritic soil and lateritic soil blended with black cotton (BC) soil, marine clay and bentonite clay were studied in the laboratory using batch adsorption techniques. In the present investigation the natural laterite soil was blended with 10%, 20% and 30% BC soil, marine clay and bentonite clay separately. The interactions on test soils have been studied with respect to the linear, Freundlich and Langmuir isotherms. The linear isotherm parameter, Freundlich and Langmuir isotherm parameters were determined from the batch adsorption tests. The adsorption of Cr (VI) on natural laterite soil and blended laterite soil was determined using double beam spectrophotometer. The distribution coefficients obtained were 1.251, 1.359 and 2.622 L/kg for lateritic soil blended with 10%, 20% and 30% BC soil; 5.396, 12.973 and 48.641 L/kg for lateritic soil blended with marine clay and 5.093, 8.148 and 12.179 L/kg for lateritic soil blended with bentonite clay respectively. The experimental data fitted well to the Langmuir model as observed from the higher value of correlation coefficient. Soil pH and iron content in soil(s) has greater influence on Cr (VI) adsorption. From the study it is concluded that laterite soil can be blended with clayey soils for removing Cr (VI) by adsorption.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.1
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• pp.35-42
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• 2009

In this study, a spark ignition engine operated with LPG and DME blended fuel was studied experimentally. The effect of n-butane and propane on performance and emissions of a SI engine fuelled by LPG/DME blended fuel were examined. Stable engine operation was achieved for a wide range of engine loads with propane containing LPG/DME blended fuel compare to butane containing LPG/DME blended fuel since octane number of propane was much higher than that of butane. Also, engine output operated with propane containing blended fuel was comparable to pure LPG fuel operation. Engine output power was decreased and break specific fuel consumption (BSFC) was increased with the blended fuel since the energy content of DME was much lower than that of LPG. Considering the results of engine output power, bsfc, and exhaust emissions, the propane containing LPG/DME blended fuel could be used as an alternative fuel for LPG.

• Educational Technology International
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• v.15 no.2
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• pp.71-88
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• 2014

A variety of studies to predict students' performance have been conducted since educational data such as web-log files traced from Learning Management System (LMS) are increasingly used to analyze students' learning behaviors. However, it is still challenging to predict students' learning achievement in blended learning environment where online and offline learning are combined. In higher education, diverse cases of blended learning can be formed from simple use of LMS for administrative purposes to full usages of functions in LMS for online distance learning class. As a result, a generalized model to predict students' academic success does not fulfill diverse cases of blended learning. This study compares two blended learning classes with each prediction model. The first blended class which involves online discussion-based learning revealed a linear regression model, which explained 70% of the variance in total score through six variables including total log-in time, log-in frequencies, log-in regularities, visits on boards, visits on repositories, and the number of postings. However, the second case, a lecture-based class providing regular basis online lecture notes in Moodle show weaker results from the same linear regression model mainly due to non-linearity of variables. To investigate the non-linear relations between online activities and total score, RF (Random Forest) was utilized. The results indicate that there are different set of important variables for the two distinctive types of blended learning cases. Results suggest that the prediction models and data-mining technique should be based on the considerations of diverse pedagogical characteristics of blended learning classes.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.23-26
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• 2002

Ternary blended concrete containing both fly ash and granulated blast furnace slag is initial cost effective, and environment friendly. Furthermore, it has many technical advantages such as improvement of long term compressive strength, rheology property, reduction of hydration heat, etc. However, use and data on the performance of ternary blended concrete are limited, and it is necessary to study on the adoption of this technology. This study examined the durability performance of ternary blended concrete comparing with binary blended concrete and ordinary portland concrete. From the results of this study, it was concluded that ternary blended concrete is very suitable to submerged zone under maine environment.

• Herbal Formula Science
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• v.11 no.1
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• pp.91-98
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• 2003

Through the research into the date of Radix Thichosanthis main blended 21 kinds of prescriptions Radix Thichosanthis from Donguibogam. This study summrized as follows; The suitable dosage of Radix Thichosanthis per one application is one to two don(about $4{\sim}8g$). Radix Thichosanthis Radix main blended prescriptions broadly use in the symptoms of diabetes, excessive thirst, cabuncles and eye diseases In diabetes and excessive thirst, the structes of Radix Thichosanthis main blended prescriptions are commonly used Seng Mak San(生脈散), Radix Puerariae(葛根), Frectus Schisandrae(五味子), Radix Ophiopogonis(麥門冬) In Furuncles, Carbuncles and Cancer like diseases, the structes of Radix Thichosanthis main blended prescriptions are generally used Kumeunhwasan(金銀花散), Jipaesan(芷貝散), Twonongsan(透膿散).

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.81-89
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• 2013

PURPOSES : This study is to evaluate ASR(alkali silica reactivity) resistance of ternary blended binder adding ultra fine mineral admixture. METHODS : This study analyzes ASR expansion using ASTM C 1260 and 1567. RESULTS : This study showed that the fineness of mineral admixture had no effect on ASR expansion. The expansion of ternary blended binder(UFFA 20%+FGGBS 10%) were below 0.1%, and this binder met the ASR standard. Also when adding the CSA expansion agent, ASR expansion slightly decreased. The expansion of latex modified mixture increased by 80% comparing plain mixture. CONCLUSIONS : Ternary blended binder met the ASR standard, and this binder is available in concrete bridge deck overlay.

• Educational Technology International
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• v.6 no.1
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• pp.81-101
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• 2005

Campus-based universities have provided face-to-face instruction traditionally. But recently, it is becoming a trend that they provide blended learning which combines e-learning and f2f instruction. Therefore, traditional university has been installing the ICT related convenience for the faculty and students to use easily to their classes. The purpose of this study is to develop quality indicators of ICT-related support for proper blended learning in traditional campus-based universities. This indicators are used for measuring the quality of ICT-related services at university level for quality education. To this end, first, we reviewed literature about quality indicators of university evaluation and e-learning. Second,we did case study. We selected and analyzed one university for a case, And we identified what elements are perceived important to faculty for more efficient use of technology to their class. Third, we summarized all this data and established the quality indicators framework of ICT-related components for blended learning in campus-based universities. Then, these indicators were revised after the expert evaluation. And then 10 experts and practitioners scored importance rating. Finally, we sum them up to 17 indicators and 48 sub-indicators in three phases (input, process, output). Among them, e-learning related organization or body, usability of Learning Management System, and quality assessment system got the highest scores. These indicators are supposed to contribute to measure the quality of ICT-related environment for blended learning and to provide informations about what is required for efficient blended learning in the campus-based universities.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.5
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• pp.53-60
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• 2009

In this study, LPG-blended DME fuel was experimentally investigated in CI(compression ignition) engine. In particular, performance, emissions characteristics (including hydrocarbon, CO, and NOx emissions), and combustion stability of engine fueled with LPG-blended DME fuel were examined. The extent of LPG fuel in the blended fuel was 0-40 wt%. Results showed that stable engine operation was possible in a wide range of engine loads on DME blended with maximum 30% of LPG by mass in a CI engine. Considering the results of the engine power output and exhaust emissions, blended fuel up to 30% of LPG by mass can be used as an alternative to diesel in a CI engine. LPG blended DME fuel is expected to have potential for enlarging the DME market.

• Herbal Formula Science
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• v.10 no.2
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• pp.5-46
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• 2002

This report describes the studies as follows through the research into the data of Cimicifuga heraclefolia Komarov blended prescriptions from Donguibogam. Cimicifuga heracleifola Komarov blended prescriptions are utilized for 39 therapeutic ranges. such as in dentistry, onclology, and 16 therapeutic ranges occupy over 84% totally, from dentistry to nasal disease. Cimicifuga heracleifola Komarov blended prescriptions use in the symptpms resulting from dentistry, intestine, internal disease, and they are used 22 disease also. The main pathologies of Cimicifuga heracleifola Komarov blended prescriptions found weakness in the digestive system, heat of stomach, wind of stomach in the splanchnology, and pathologies of wind-heat, wind-moisture, cold, excluding they are using for energy-blood, weakness, internal disease. The actual amount of Cimicifuga heracleifola Komarov blended has a wide capacity from 2 pun to 5 don, 1 don is broadlly used by 26%. Through the research into the main factors that we know Cimicifuga heracleifola Komarov blended prescriptions are listed in Yangmyungkyung, as they are regularly used as disease treatment and increasing the level of the general energy of the body, relaxing a skin, increasing stamina, detoxication, eliminating tumor, widely.