• Elastomers and Composites
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• v.53 no.3
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• pp.175-180
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• 2018

Solution-styrene-butadiene rubber (SSBR) composites were manufactured using four kinds of fillers: silica-silane coated carbon black (SC-CB) hybrid, starch-SC-CB hybrid, pure silica, and pure starch. The influence of filler type on the mechanical properties of the rubber matrix was studied in this work. SC-CB was prepared by silane-graft-coating using vinyl triethoxy silane and carbon black, which enhanced the dispersion effect between the rubber matrix and the filler, and improved the mechanical properties of the compounds. The morphology of the composites was observed by field-emission scanning electron microscopy (FE-SEM). The thermal decomposition behavior of the composites was determined by thermogravimetric analysis (TGA), and the crosslinking behavior of the composites was tested using a rubber process analyzer (RPA). The hardness, tensile strength, swelling ratio, and gas transmittance rate of the composites were evaluated according to ASTM. The test results revealed that with the addition of SC-CB, the hybrid fillers, especially those blended with silica, showed a better reinforcement effect, the highest hardness and tensile strength, and stable thermal decomposition behavior. This implies that the silica-SC-CB hybrid filler has a notable mechanical reinforcement effect on the SSBR matrix. Because of self-crosslinking during its synthesis, the starch-SC-CB hybrid filler produced the most dense matrix, which improved the anti-gas transmittance property. The composites with the hybrid fillers had better anti-swelling properties as compared to the neat SSBR composite, which was due to the hydrophilicity of silica and starch.

• The Journal of Korean Association of Computer Education
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• v.6 no.1
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• pp.109-120
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• 2003

Recently, as more web-based applications are widely used, various methods for education are developed in practical areas. As a result, in many organizations, virtual educations such as WBI learning. CAI, and distance learning are offered actively. With the advantages of web-based education, in order to achieve feasible and efficient effects on education. a new web-based instruction model that considers the abilities, the interests, and the aptitudes of students individually is required. In this paper, a new web-based instruction model, called a hybrid model, is proposed and implemented. And then, two model - the stepwise model and the hybrid model- are applied to a computer accounting class of a vocational high school. Students attend the web-based class in a computer center for 100 minutes autonomously. After the classes, a questionnaire is made in order to analyze both the effect on that class and the learning fulfillment of the proposed instruction model.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.1
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• pp.49-54
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• 2016

The large scaled lead-acid battery is widely used for efficient operation of the photovoltaic system in many islands. However, lithium-ion battery is now being introduced to mitigate the fluctuation of wind power and to replace lead-acid battery. Therefore, hybrid ESS (Energy Storage system) that combines lithium-ion battery with lead-acid battery is being required because lithium-ion battery is costly in present stage. Under this circumstance, this paper presents the optimal algorithm to create composition rate of hybrid ESS by considering fixed and variable costs in order to maximize advantage of each battery. With minimization of total cost including fixed and variable costs, the optimal composition rate can be calculated based on the various scenarios such as load variation, life cycle and cost trend. From simulation results, it is confirmed that the proposed algorithms are an effective tool to produce a optimal composition rate.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1675-1680
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• 2014

A peroxopolyoxotungsten-based ionic hybrid was synthesized by anion-change of peroxopolyoxometalate (POM) $PW_4O{_{24}}^{3-}$ with dicationic long-chain alkyl imidazolium ionic liquids. The characterization was conducted by FT-IR, TGA, $^1H$-NMR and CHN Elemental analyses. Its catalytic performance was evaluated by the epoxidation of soybean oil with $H_2O_2$ under solvent-free condition, including testing of organic cations influence, catalytic reusability and reaction conditions. The catalyst was proved to be a highly efficient recyclable catalyst for epoxidation of various vegetable oils with $H_2O_2$, showing high $H_2O_2$ utilization efficiency, high catalytic activity, convenient recovery and good reuse ability.

• Mycobiology
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• v.31 no.3
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• pp.151-156
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• 2003

Two fungal isolates obtained from roots of Cymbidium goeriingii in Jeju island were confirmed to be symbiotic with orchid plantlets, and were compared with other orchid mycorrhizal(OM) fungi previously isolated. The two isolates differed in their peloton structures formed in the roots of Cymbidium kanran hybrid 'Chungsu' and in responses of orchid plant. These two isolates differed from the additionally tested OM fungi in some features, and from root damaging species of Rhizoctonia and Fusarium as based on cluster analysis after PCR-RAPD with the primers, Bioneer-28 and OPO-2. With this simple and fast technique, it was possible to distinguish OM fungi from the plant root pathogenic fungi based on calculation of their polymorphic bands. This technique can therefore be helpful to distinguish the OM fungi from the root pathogens. Particularly, the new isolates are considered as new resource of symbiotic fungi for horticultural industries.

• Carbon letters
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• v.27
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• pp.72-80
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• 2018

In the present work, a comparative study of the mechanical behavior of two series of elastomeric composites, based on carboxylated styrene butadiene rubber (X-SBR) and reinforced with rice bran carbon (RBC) and graphite, is reported. Hybrid composites of X-SBR filled with RBC-graphite were also investigated in terms of the cure characteristics, hardness, tensile properties, abrasion resistance, and swelling. It was observed that the cure times decreased with the incorporation of a carbon filler whereas the torque difference, tensile strength, tensile modulus, hardness, and swelling resistance increased compared to the neat X-SBR revealing a favorable characteristic of crosslinking. Dynamic rheological analysis showed that the G' values of the composites, upon the addition of RBC-graphite, were changed to some extent. This demonstrates that the presence of a strongly developed network of fillers will ensure a reinforcing characteristic in a polymer matrix.

• The Journal of Korean Academic Society of Nursing Education
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• v.29 no.1
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• pp.27-40
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• 2023

Purpose: The study aimed to examine the concept and attributes of the quality of clinical nursing education for new graduate nurses. Methods: This study adopted a hybrid model introduced by Schwartz-Barcott and Kim. In the theoretical stage, the meaning and attributes of the quality of clinical nursing education for new graduate nurses were determined by analyzing eight articles. In the fieldwork stage, data were collected using semi-structured interviews with five new graduate nurses and seven experienced nurses. The data were analyzed by qualitative content analysis methods developed by Elo and Kyngӓs. In the final analysis, a final result was arrived at comparing, contrasting, and integrating the attributes of the concepts derived in the theoretical and field-work stages. Results: The quality of clinical nursing education for new graduate nurses was identified as excellence or the standard of education for new graduate nurses that would support them in adapting to clinical settings and transitioning to professional nurses. The attributes of the quality of clinical nursing education were founded to possess three dimensions, six categories, and 18 attributes. The multidimensional attributes of the quality of clinical nursing education for new graduate nurses were confirmed as education resources, design, method, content, evaluation, interaction, and outcome under the three dimensions of input, process, and output. Conclusion: The concept and nature of the quality of clinical nursing education observed in this study can be utilized as a basis for the future development, evaluation, and improvement of clinical nursing education for new graduate nurses in healthcare organizations.

• Proceedings of The KACE
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• 2017.08a
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• pp.57-59
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• 2017

대화 시스템(dialogue system)은 텍스트나 음성을 통해 다양한 분야에서 특정한 목적을 수행할 수 있는 시스템이다. 대화 시스템을 구현하기 위한 방법으로 인공 신경망(neural network)을 기반으로한 end-to-end learning 방식이 제안되었다. End-to-end learning 방식을 이용한 식당 예약 시스템 모델의 학습을 위해 페이스북은 영어로 이루어진 식당 예약에 관련된 학습 대화 데이터셋(The 6 dialog bAbI tasks)을 구축하였다. 하지만 end-to-end learning 방식의 학습은 많은 학습 데이터가 필요하다는 단점이 존재하는데, 액션 템플릿(action template)의 정의를 통해 도메인 지식을 표현함으로써 일반적인 end-to-end learning 방식보다 적은 학습량으로 좋은 성능의 모델을 학습할 수 있는 Hybrid Code Network 구조를 제안한 연구가 있다. 본 논문에서는 Hybrid Code Network 구조를 이용하여 한국어 식당 예약 시스템을 구축할 수 있는 방법을 제안하고, 한국어로 이루어진 식당 예약에 관련한 학습 대화 데이터를 구축하는 방법을 제안한다.

• Journal of Advanced Navigation Technology
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• v.15 no.2
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• pp.281-286
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• 2011

Data sorting is one of important pre-process to utilize huge data in modern society, but sorting spends a lot of time by sorting itself. In this paper, we presented hybrid sorting algorithm that splits array to sort concurrently in CPU and GPU. To do this, we decided most effective range of array based on hardware performance, then accomplished reducing whole sorting time by concurrent sorting on CPU and GPU. As shown in results of experiment, hybrid sorting improved about eight percent of sorting time in comparison with the sorting time using only GPU.

• The Pure and Applied Mathematics
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• v.26 no.3
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• pp.111-131
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• 2019

We introduce (CLRg) property for hybrid pair $F:X{\times}X{\rightarrow}2^X$ and $g:X{\rightarrow}X$. We also introduce joint common limit range (JCLR) property for two hybrid pairs $F,G:X{\times}X{\rightarrow}2^X$ and $f,g:X{\rightarrow}X$. We also establish some common coupled fixed point theorems for hybrid pair of mappings under generalized (${\psi},{\theta},{\varphi}$)-contraction on a noncomplete metric space, which is not partially ordered. It is to be noted that to find coupled coincidence point, we do not employ the condition of continuity of any mapping involved therein. As an application, we study the existence and uniqueness of the solution to an integral equation. We also give an example to demonstrate the degree of validity of our hypothesis. The results we obtain generalize, extend and improve several recent results in the existing literature.