• Applied Chemistry for Engineering
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• v.32 no.3
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• pp.229-236
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• 2021

During the last two decades, metal-organic frameworks (MOFs) have been drawn attention due to their high specific surface area, porosity, and catalytic activities that allow to use in many applications such as sensor, catalysis, energy storage, etc. To synthesize MOFs hydrothermal or solvothermal method were generally used. However, these methods require high-cost equipment and long time-spend for the synthesis with multi-step process. In contrast, electrochemical synthesis has been considered as a simple and easy process under the ambient conditions. In this review, we described the mechanism of electrochemical MOFs synthesis by the number of configured electrodes system, with the recent reports of various applications.

• Applied Chemistry for Engineering
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• v.34 no.2
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• pp.180-185
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• 2023

To improve the efficiency of water electrolysis, it is essential to develop an oxygen evolution reaction (OER) electrocatalyst with high performance and long-term stability, accelerating the reaction rate of OER. In this study, a hollow metal-organic framework (MOF)-derived ruthenium-cobalt oxide catalyst was developed to synthesize an efficient OER electrocatalyst. As the synthesized catalyst increases the surface exposure of ruthenium, a low overpotential (386 mV) was observed at a current density of 10 mA/cm² with a low Tafel slope. It is expected to be able to replace noble metal catalysts by showing higher mass activity and stability than commercial RuO₂ catalysts.

• The Journal of Advanced Prosthodontics
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• v.15 no.2
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• pp.55-62
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• 2023

PURPOSE. The aim of this study is to evaluate the accuracy of removable partial denture (RPD) frameworks produced using different digital protocols. MATERIALS AND METHODS. 80 frameworks for RPDs were produced using CAD-CAM technology and divided into four groups of twenty (n = 20): Group 1, Titanium frameworks manufactured by digital metal laser sintering (DMLS); Group 2, Co-Cr frameworks manufactured by DMLS; Group 3, Polyamide PA12 castable resin manufactured by multi-jet fusion (MJF); and Group 4, Metal (Co-Cr) casting by using lost-wax technique. After the digital acquisition, eight specific areas were selected in order to measure the Δ-error value at the intaglio surface of RPD. The minimum value required for point sampling density (0.4 mm) was derived from the sensitivity analysis. The obtained Δ-error mean value was used for comparisons: 1. between different manufacturing processes; 2. between different manufacturing techniques in the same area of interest (AOI); and 3. between different AOI of the same group. RESULTS. The Δ-error mean value of each group ranged between -0.002 (Ti) and 0.041 (Co-Cr) mm. The Pearson's Chi-squared test revealed significant differences considering all groups paired two by two, except for group 3 and 4. The multiple comparison test documented a significant difference for each AOI among group 1, 3, and 4. The multiple comparison test showed significant differences among almost all different AOIs of each group. CONCLUSION. All Δ-mean error values of all digital protocols for manufacturing RPD frameworks optimally fit within the clinical tolerance limit of trueness and precision.

• Journal of Electrochemical Science and Technology
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• v.14 no.1
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• pp.85-95
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• 2023

In recent years, solid-state Li metal batteries (SSLBs) have attracted significant attention as the next-generation batteries with high energy and power densities. However, uncontrolled dendrite growth and the resulting pulverization of Li during repeated plating/stripping processes must be addressed for practical applications. Herein, we report a plastic-crystal-based polymer/ceramic composite solid electrolyte (PCCE) to resolve these issues. To fabricate the one-side ceramic-incorporated PCCE (CI-PCCE) film, a mixed precursor solution comprising plastic-crystal-based polymer (succinonitrile, SN) with garnet-structured ceramic (Li₇La₃Zr₂O₁₂, LLZO) particles was infused into a thin cellulose membrane, which was used as a mechanical framework, and subsequently solidified by using UV-irradiation. The CI-PCCE exhibited good flexibility and a high room-temperature ionic conductivity of over 10^-3 S cm^-1. The Li symmetric cell assembled with CI-PCCE provided enhanced durability against Li dendrite penetration through the solid electrolyte (SE) layer than those with LLZO-free PCCEs and exhibited long-term cycling stability (over 200 h) for Li plating/stripping. The enhanced Li⁺ transference number and lower interfacial resistance of CI-PCCE indicate that the ceramic-polymer composite layer in contact with the Li anode enabled the uniform distribution of Li⁺ flux at the interface between the Li metal and CI-PCCE, thereby promoting uniform Li plating/stripping. Consequently, the Li//LiFePO₄ (LFP) full cell constructed with CI-PCCE demonstrated superior rate capability (~120 mAh g^-1 at 2 C) and stable cycle performance (80% after 100 cycles) than those with ceramic-free PCCE.

• The Research Journal of the Costume Culture
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• v.6 no.4
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• pp.84-103
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• 1998

The purpose of this study si focused on Futurism style and contemporary fashion in the 20th century, by researching the Giacomo Balla, Fortunato Depero, Tullio Crali, Erenesto Thayate characteristics fashion design. The results of this study are following as : The general traits of Futurism style are classified with aesthetics, formative characteristics. First, aesthetic characteristics are based on H. Bergson's life-phylosophy and F. Nietzche's art theory. Second, formative characteristics is Dynamism. Futurism Dynamism are classified with psychological Dynamism and physical Dynamism. Futurism trends in the costume : first, dynamism in fashion design, second, asymmetrical balance, third, formativeness, forth, technology, fifth, anti-traditionalism. Dynamism are expressed textile, pattern and costuem shape in contemporary dress. Asymmetrical balance are expressed costume silhouette shape and framework through the geometrical asymmetrical balance. Formativeness are agree with Paco Rabanne's fashion design expressed body and movement and phychological world of human through the secondly fabric. Technology are expressed new mechanical dynamism in used technology art and new fashion material by metal. The last, anti-traditionalism is recognized new value and idea in fashion.

• The Journal of the Korean dental association
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• v.27 no.6 s.241
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• pp.527-530
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• 1989

국소의치에 있어서 인공치는 기능적 관점에서와 심미적 관점에서 중요한 구성요소중의 하나이다. 구치는 저작기능을 회복시켜주며 악궁간 거리를 유지하여 주며 상실된 안모의 형태를 회복시켜준다. 전치는 저작기능의 회복뿐만 아니라 심미성을 회복시켜주며 발음 기능에 있어 중요한 역할을 한다. 이러한 인공치의 기능을 위해서는 인공치는 여러 요구조건을 갖게되는데, 무치악 공간에 잘 맞아야 하며 metal framework에 잘 맞아야 하고 깨지지 말아야 하며 마모되지 않아야 하고 유해한 작용이 없이 어떤 교합형태를 갖거나 어떤 재료로 되어 있는 치아이던지 잘 교합될 수 있어야 한다. 이러한 이상적인 인공치는 없으나 국소의치의 요구를 만족시켜줄 수 있는 여러 종류의 인공치의 이용이 가능하므로 이러한 인공치의 장점과 단점을 이해하여 국소의치 제작시 가장 적당한 인공치를 선택하여 사용하는 것이 중요하다.

• Journal of Photoscience
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• v.10 no.1
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• pp.127-148
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• 2003

Zeolite is a porous highly interactive matrix. Zeolitic cations help to generate triplets from molecules that possess poor intersystem crossing efficiency. Certain zeolites act as electron acceptors and thus can spontaneously generate radical cations. Zeolites also act as proton donors and thus yield carbocations without any additional reagents. These reactive species, radical cations and carbocations, have long lifetime within a zeolite and thus lend themselves to be handled as ‘regular’ chemicals. Internal structure of zeolites is studded with cations, the counter-ions of the anionic framework. The internal constrained structure and the cations serve as handles for chemists to control the behavior of guest molecules included within zeolites.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.627-632
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• 1994

This study suggests the contingency framework understanding the implementation of NIMT and conducts empirical analysis using survey data. The main objectives of the thesis are as follows : (1) analyzing the relationship between adaptation requirements and organizational adaptation efforts. (2) analyzing the relationship between organizational adaptation efforts and implementation performance, and the moderating effect of the adaptation requirements. (3) analyzing the relationship between organizational adaptation efforts and organization characteristics(organization size, technical capability, top management support). A field study was undertaken to test the hypothesized relationships among adaptation efforts, adaptations requirements, organization characteristics, implementation performance. Data were collected from 52 NMT implementation projects of 45 machine tool, metal component firms. The emprical relflts indicated that adaptation requirrnents, organization characteristics were significantly related to organizational adaptation efforts and adaptation efforts can significantly improve implementation perfomance, but the moderating effect of adaptation requirements on adaptation efforts and implementation performance was not supported.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.4
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• pp.92-97
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• 2007

A temporary structure is a framework of metal poles and planks, used as a working platform from which building repairs or construction can be carried out safety. The manufacturing process of the existing model consumes a many hour. So, it is modified manufacturing process. In this study, it is attempted to find out the shape of modified working platform considering manufacturing process and using Taguchi method, and it reduces production process. The design parameters are defined to discribe shape of model. As a result of the shape design, maximum Von-Mises stress and displacement considering a safety factor were satisfied with CTEA (Construction Temporary Equipment Association of Korea) standard.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.715-725
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• 1994

The objective of this research is to develop a cost model for integrated CAD system. A computerized system realizing this model then is used to aid designers. The first area is to propose a conceptual framework of a multilevel cost model. The methodology of constructing the model is discussed. Then suggestion of an object oriented programming technique for implementing the model is presented. Complicate estimation procedure can be systematically handled by this technique. Interval analysis to deal with the uncertainty of information and decision during design process is used. An experimentation algorithm for calculating the cost distribution is proposed to overcome the shortcoming of interval analysis. Major focus of this research is on net shape manufacturing processes including die casting, injection molding, and metal forming.