• Structural Engineering and Mechanics
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• 제85권5호
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• pp.573-592
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• 2023

This paper presents a careful theoretical investigation into interfacial stresses in composite aluminum-slab reinforced concrete beam bonded by a prestressed hybrid carbon-glass composite material. The model is based on equilibrium and deformations compatibility requirements in and all parts of the strengthened beam, i.e., the aluminum beam, the slab reinforced concrete, the hybrid carbon-glass composite plate and the adhesive layer. The theoretical predictions are compared with other existing solutions. Numerical results from the present analysis are presented both to demonstrate the advantages of the present solution over existing ones and to illustrate the main characteristics of interfacial stress distributions. It is shown that the stresses at the interface are influenced by the material and geometry parameters of the composite beam. This research is helpful for the understanding on mechanical behaviour of the interface and design of the hybrid structures.

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2005년도 추계 학술발표대회 논문집
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• pp.84-85
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• 2005

• 패션비즈니스
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• 제24권5호
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• pp.125-139
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• 2020

The fashion industry that perceived the severity of environmental pollution, has sought various methods of sustainable fashion. However, most of the businesses paid attention to the development of materials using industrial waste, or vegan material. Thus, this study aims to present the methods for improvement in creativity for inversely developing the design from patterns and present new approaches by applying the contrarian development of proto to class under the limited condition of material concerning general design, selection of material, and production of sample. In the case of three student teams enrolled in the first semester of the second year, the fabric and used clothing donated by industry were used as material. The whole cut for cutting a single fabric in connected state, and Zero Wastes Design within a rectangular frame of fabric, upcycling of used clothes, and cutting out of Geometric Form are suggested. The team(A) produced a zero-wastes coat and whole-cut Pancho that could be variously represented. The team(B) produced two kinds of asymmetric dress by utilizing used check-patterned shirts through upcycling. The team(C) utilized the fabric in geometric forms such as rectangle, trapezoid, and atypical figure by drawing design within donated fabrics. The items were a dress, blouse, and skirt. Consequently, an opportunity for both academia and industry to present more concrete methods for sustainable fashion and deeply perceive the sustainable fashion is presented along with novel methods for creation by carrying out the composition of pattern and design at the same time.

• Computers and Concrete
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• 제30권6호
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• pp.393-407
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• 2022

Due to the enormous cement content, pozzolanic materials, and the use of different aggregates, sustainable controlled low-strength material (CLSM) has a higher material cost than conventional concrete and sustainable construction issues. However, by selecting appropriate materials and formulations, as well as cement and aggregate content, whitethorn costs can be reduced while having a positive environmental impact. This research explores the desire to optimize plastic properties and 28-day unconfined compressive strength (UCS) of CLSM containing powder content from unprocessed-fly ash (u-FA) and recycled fine aggregate (RFA). The mixtures' input parameters consist of water-to-cementitious material ratio (W/CM), fly ash-to-cementitious materials (FA/CM), and paste volume percentage (PV%), while flowability, bleeding, segregation index, and 28-day UCS were the desired responses. The central composite design (CCD) notion was used to produce twenty CLSM mixes and was experimentally validated using MATLAB by an Artificial Neural Network (ANN). Variance analysis (ANOVA) was used for the determination of statistical models. Results revealed that the plastic properties of CLSM improve with the FA/CM rise when the strength declines for 28 days-with an increase in FA/CM, the diameter of the flowability and bleeding decreased. Meanwhile, the u-FA's rise strengthens the CLSM's segregation resistance and raises its strength over 28 days. Using calcareous powder as a substitute for cement has a detrimental effect on bleeding, and 28-day UCS increases segregation resistance. The response surface method (RSM) can establish high correlations between responses and the constituent materials of sustainable CLSM, and the optimal values of variables can be measured to achieve the desired response properties.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.37-38
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• 2007

This paper reports the characteristics of piezoelectric microspeakers that are audible in open air with high quality piezoelectric AlN thin film according to the materials properties. When we use a tensile-stressed silicon nitride diaphragm as a supporting layer, the Sound Pressure Level (SPL) is relatively small. However, the SPL of the fabricated microspeakers that have compressive-stressed composite diaphragm show higher output pressure than those of tensile-stressed diaphragm. It produces more than 60dB from 100Hz to 15kHz and the highest SPL is about 100dB at 9.3kHz with 20 Vpeak-to-peak sinusoidal input biases and at 10 mm distances from the fabricated microspeakers to the reference microphone.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.602-603
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• 2006

Micro-porous nickel (Ni) with an open cell structure was fabricated by powder metallurgy. The pore size of the micro-porous Ni approximated $30{\mu}m$ and $150{\mu}m$. For comparison, porous Ni with a macro-porous structure were also prepared by both powder metallurgy (pore size $800{\mu}m$) and the traditional chemical vapour deposition method (pore size $1300{\mu}m$). The mechanical properties of the micro-and macro-porous Ni samples were evaluated using compressive tests. Results indicate that the micro-porous Ni samples exhibited significantly enhanced mechanical properties, compared to those of the macro-porous Ni samples.

• 자원환경지질
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• 제41권2호
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• pp.253-265
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• 2008

지속가능한 자원관리모형(SRM)구축은 탈물질화 및 환경과 경제의 디커플링을 이루기 위한 핵심적 요소로 여겨지고 있다. 본 연구에서는 세계 각국의 지속가능한 자원관리 정책 및 연구방향을 살펴보고, decoupling factor를 이용하여 국내제조업의 경제활동과 에너지소비간의 디커플링현상을 살펴보았다. 마지막으로 이를 바탕으로 국내 실정에 맞는 SRM모형구축과 전략을 제시하였다. 자원관리 시스템은 수요전망, 물질흐름분석과 가치사슬분석, 시장구조분석 등의 분석과 조사 등을 바탕으로 구축된다. 이러한 분석들을 통해 환경적 문제 해결, 재활용시장관리방안 및 시장의 구조적 문제점 도출, 필요 재활용기술 도출, 1차자원과 2차자원의 최적 공급비율 등의 Hot-spot 도출 및 해결방안모색이 가능하다. 또한 지속가능한 자원 관리시스템과 국가단위, 권역단위의 물질흐름분석을 유기적으로 연계하고, 효과적인 이의 운영을 위해서는 국가차원의 법제화와 뒷받침이 이뤄져야 할 것이다.

• 복식문화연구
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• 제29권4호
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• pp.538-553
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• 2021

As interest in the sustainable fashion industry continues to increase along with climate issues, it is necessary to identify research trends in sustainable fashion and seek new development directions. Therefore, this study aims to analyze research trends on sustainable fashion. For this purpose, related papers were collected from the KCI (Korean Citation Index) and Scopus, and 340 articles were used for the study. The collected data went through data transformation, data preprocessing, topic modeling analysis, core topic derivation, and visualization through a Python algorithm. A total of eight topics were obtained from the comprehensive analysis: consumer clothing consumption behavior and environment, upcycle product development, product types by environmental approach, ESG business activities, materials and material development, process-based approach, lifestyle and consumer experience, and brand strategy. Topics were related to consumption, production, and education of sustainable fashion, respectively. KCI analysis results and Scopus analysis results derived eight topics but showed differences from the comprehensive analysis results. This study provides primary data for exploring various themes of sustainable fashion. It is significant in that the data were analyzed based on probability using a research method that excluded the subjective value of the researcher. It is recommended that follow-up studies be conducted to examine social trends.

• Advances in materials Research
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• 제12권2호
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• pp.119-131
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• 2023

The development of sustainable composites materials, from recycled polymeric materials and waste from the wood industry and stone processing, allows reducing the volume of these by-products, minimizing impacts on health and the environment. Nowadays, Polypropylene (PP) is the most recycled polymer in industry, while the furniture industry has increasingly used timber felled from sustainable forest plantations as a eucalypt. The powder tailing from the ornamental stone extraction and processing industry is commonly disposed of in the environment without previous treatment. Thus, the technological option for the development of composite materials presents itself as a sustainable alternative for processing and manufacturing industries, enabling the development of new materials with special technical features. The results showed that powder granite particles may be incorporated into the polypropylene matrix associated with short eucalyptus fibres forming green hybrid composites with potential application in structural engineering, such as transport and civil construction industries.

• Advances in nano research
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• 제16권1호
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• pp.53-69
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• 2024

Advancements in the technology of building materials has led to diverse applications of nanomaterials with the aim to monitor concrete structures. While there are myriad instances of the use of nanoparticles in building materials, the production of smart nano cement-composites is often expensive. Thereupon, this research aims to discover a sustainable nanomaterial from tyre waste using the pyrolysis process as part of the green manufacturing circle. Here, Nano Structure Tyre-Char (NSTC) is introduced as a zero-dimension carbon-based nanoparticle. The NSTC particles were characterized using various standard characterization techniques. Several salient results for the NSTC particles were obtained using microscopic and spectroscopic techniques. The size of the particles as well as that of the agglomerates were reduced significantly using the milling process and the results were validated through a scanning electron microscope. The crystallite size and crystallinity were found to be ~35nm and 10.42%, respectively. The direct bandgap value of 5.93eV and good optical conductivity at 786 nm were obtained from the ultra violet visible spectroscopy measurements. The thermal analysis reveals the presence of a substantial amount of carbon, the rate of maximum weight loss, and the two stages of phase transformation. The FT-Raman confirms the presence of carboxyl groups and a ID/IG ratio of 0.83. Water contact angle around 140° on the surface implies the highly hydrophobic nature of the material and its low surface energy. This characteristic process assists to obtain a sustainable nanomaterial from waste tyres, contributing to the development of a smart building material.