• Journal of Dairy Science and Biotechnology
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• 제23권1호
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• pp.27-37
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• 2005

The development of functional foods started booming from several years ago in the world. The size of functional materials are in the range of micrometer level. This size can be much smaller into nanometer level to be more effective. We face some problems from the materials, such as flavor, taste, color, viscosity, etc. in functional materials. The problems can be solved by micro / nanoencapsulation technique. This paper showed some results of the research related on the technique for functional milks and dairy products. The nono / microcapsules are the form of liquid instead of solid. Coating materials used were fatty acid esters, and core materials were lactase, iron, ascorbic acid. isoflavone, and chitooligosaccharide. The ranges of capsules are from 100 nm to 200 ${\mu}$m. The sample milks added nano/microcapsules were homogeneous and prevented the defects of core materials. It was observed that nano / microcapsules in milk and dairy products were effective as functional material without defaults. It was indicated that targeted functional foods can be developed further in various foods by nanotechnology.

• 한국구조물진단유지관리공학회 논문집
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• 제6권1호
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• pp.205-212
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• 2002

The deterioration rate of concrete structures in urban area is accelerated due to rapid urbanization and environmental pollution. Repair materials and methods newly introduced in Korea should be investigated whether they are appropriate for the urban environment in Korea. The creek concrete structures are exposed in severe environmental condition than others. Based on these background in mind, the study is focused on evaluation of performance on repair materials used to rehabilitate creek concrete structures. To evaluate the performance of repair materials, four kinds of repair materials were selected based on polymer emulsion. This experimental study was conducted on fundamental performance such as setting time, compressive strength, bending strength, bonding strength, thermal expansion coefficient, and durability performance such as chloride diffusion, carbonation, chemical attack, and steel corrosion rate. On the basis of this study, the optimal repair material which is proper to the environment condition can be selected and service life of creek concrete structures can be extended. As a result, the life cycle cost can be reduced and the waste of material resources will be cut down.

• 세라미스트
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• 제21권4호
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• pp.416-426
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• 2018

Water splitting is regarded as one of the most environmentally benign routes for hydrogen production. Nevertheless, the low energy efficiency to produce the hydrogen has been a critical bottleneck, which is attributable to the multi-electron and multi-step reactions during water splitting reaction. In this respect, the development of efficient, durable, and inexpensive catalysts that can promote the reaction is indispensable. Extensive searching for new catalysts has been carried out for past decades, identifying several promising catalysts. Recently, researchers have found that conventional battery materials; particularly high-voltage intercalation-based cathode materials, could exhibit remarkable performance in catalyzing the water splitting process. One of the unique capabilities in this class of materials is that the valency state of metals and the atomic arrangement of the structure can be easily tailored, based on simple intercalation chemistry. Moreover, taking advantage of the rich prior knowledge on the intercalation compounds can offer the unexplored path to identify new water splitting catalysts.

• 한국재료학회지
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• 제30권9호
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• pp.480-488
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• 2020

The electrocaloric effect can be observed in pyroelectric materials based on conversion between electrical and thermal energy, and can be utilized for the future environment-friendly refrigeration technology. Especially, a strong electrocaloric effect is expected in materials in which field-induced phase transition can be achieved. Emerging fluorite-structure ferroelectrics such as doped hafnia and zirconia, first discovered in 2011, are considered the most promising materials for next-generation semiconductor devices. Besides application of fluorite-structure ferroelectrics for semiconductor devices based on their scalability and CMOS-compatibility, field-induced phase transition has been suggested as another interesting phenomenon for various energy-related applications such as solid-state cooling with electrocaloric effect as well as energy conversion/storage and IR/piezoelectric sensors. Especially, their giant electrocaloric effect is considered promising for solid-state-cooling. However, the electrocaloric effect of fluorite-structure oxides based on field-induced phase transition has not been reviewed to date. In this review, therefore, the electrocaloric effect accompanied by field-induced phase transition in fluorite-structure ferroelectrics is comprehensively reviewed from fundamentals to potential applications.

• 청정기술
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• 제17권1호
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• pp.1-12
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• 2011

과학자와 공학자들은 끊임없이 금속, 합금, 고분자, 세라믹 등의 공학재료의 성질을 계속해서 변화하는 사회의 요구에 부응하는 방향으로 개선하여 왔다. 인조 공학재료는 일반적으로 기계적 성질이 우수하여, 자연 재료의 기계적 성질보다 우수한 경우가 많다. 그러나, 이와 같은 공학 재료는 자연계에서 흔히 볼 수 있는 자기 치유능력, 즉 고의적인 인간의 접촉을 거치지 않고도 미세균열을 제거하는 능력이 부족하다. 자연에서 관측할 수 있는 손상관리 패러다임은 여러 가지 종류의 공학재료의 고유성질을 잘 고려하면 인조공학 재료에서도 성공적으로 재현할 수 있다. 특히 적절한 화학반응과 분자간력을 응용하면 고분자, 아이오노머, 복합체와 같은 유기재료에 적용할 수 있는 다양한 자기치유 방법을 개발할 수 있다.

• Carbon letters
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• 제28권
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• pp.1-8
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• 2018

Graphene is a single atomic layer of carbon atoms, and has exceptional electrical, mechanical, and optical characteristics. It has been broadly utilized in the fields of material science, physics, chemistry, device fabrication, information, and biology. In this review paper, we briefly investigate the ideas, structure, characteristics, and fabrication techniques for graphene applications in lithium ion batteries (LIBs). In LIBs, a constant three-dimensional (3D) conductive system can adequately enhance the transportation of electrons and ions of the electrode material. The use of 3D graphene and graphene-expansion electrode materials can significantly upgrade LIBs characteristics to give higher electric conductivity, greater capacity, and good stability. This review demonstrates several recent advances in graphene-containing LIB electrode materials, and addresses probable trends into the future.

• 한국가정과교육학회지
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• 제12권3호
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• pp.145-156
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• 2000

This study was intended to develop an efficient web-based instruction materials in clothing unit. The clothing unit was chosen because this unit was supposed to be appropriate to analyze and utilize web. By using languages of html asp, the study developed web materials to use this unit and constructed this unit into web site. Finally the study tried to examined educational effect by performing the constructed web site and representing some ways which can be applied in the classroom. The result of this study can be summed up as follows: $\circled1$The web materials were developed with steps of planning longrightarrowdesigninglongrightarrowdevelopmentlongrightarrowevaluation. In each step detailed activities, content analysis examples of developed materials, which presents the concrete procedures and directions were specified. $\circled2$The web materials were developed to be able to change an add up the materials in the web site. $\circled3$The web materials were developed by teaching-leaning model and the lesson plan, and then they are applied. $\circled4$Instruction materials were developed according to the lesson plan and in concrete ways.

• 한국세라믹학회지
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• 제40권11호
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• pp.1027-1046
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• 2003

Nanostructured materials can be engineered by the controlled assembly of several suitable nano-objects as the building blocks. While, materials properties are determined by their atomic and molecular constituents and structure, their functionalities emerge when the microstructure of these early ensembles is in the nanometer regime. The properties and functionalities of these ensembles may be different as their size grows from the nano-regime to the micron regime and bulk structures. Nanotechnology, offers a unique possibility to manipulate the properties through the fabrication of materials using the nano-objects as building blocks. Nanotechnology is therefore considered an enabling technology by which existing materials, virtually all man-made materials, can acquire novel properties and functionalities making them suitable for numerous novel applications varying from structural and functional to advanced biomedical in-vivo and in-vitro applications.

• 자원리싸이클링
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• 제9권2호
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• pp.3-10
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• 2000

알루미늄 폐캔은 중요한 재활용 자원으로서 알루미늄 캔용 원소재 판재는 물론 알루미늄의 국내소요량을 전량 수입에 의존하고 있는 우리나라로서는 활용 가능한 알루미늄폐캔의 재활용율을 높여야 하는 것은 외화절약과 환경보호 측면에서 대단히 중요하다. 사용한 알루미늄 캔을 다시 캔으로 재활용 하는 단계는 폐캔의 수집, 파쇄, 선별, 도료제거, 용해 및 2차지금을 제조하는 단계와 이 2차지금을 이용하여 열처리, 열간 및 냉간압연, 중간소둔처리 등을 거쳐 다시 캔을 성형하는 2단계로 나눌수 있다. 본 자료에서는 이러한 알루미늄 캔의 재활용 기술에 대한 우리나라와 선진국들의 현황과 전망을 소개하였다.

• 한국학교수학회논문집
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• 제4권1호
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• pp.115-124
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• 2001

This research is focused on the development of Math teaching and/or learning materials in which the students are centered, not teachers, and which can, in turn, activate and reinforce the students' extra curricular Math activitie The findings I came to have through my research can be summarized as follows: 1. Math teaching and/or learning materials developed based on the students' interactions in the Math extra-curricular activities helped students to learn Math better and to be more interested in Math. 2. There was a positive attitude change toward Math on the side of the students after being introduced in and exposed to Math through the above mentioned Math teaching and/or learning materials. 3. There was a positive attitude change toward Math on the side of the students after being taught Math using the above mentioned Math teaching and/or learning materials. The suggestions I came to have through my research are as follows: 1. There need to be more consistent efforts in developing the Math teaching and/or learning materials which can be used in the Math extra-curricular activities. 2. There need to be more consistent efforts in developing Math teaching paradigms which can be used in Math extra-curricular activities. 3. There need to be more consistent efforts in developing the Math teaching and/or learning materials which can be used in the Math class as well as in Math extra-curricular activities. 4. There need to be more consistent efforts in developing the Math teaching and/or learning materials which are more grade-, unit-, and category-conscious.