• Elastomers and Composites
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• v.56 no.3
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• pp.136-151
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• 2021

Biomass lignin, a waste produced during the paper and bio-ethanol production process, is a cheap material that is available in large quantities. Thus, the interest in the valorization of biomass lignin has been increasing in industrial and academic areas. Over the years, lignin has been predominantly burnt as fuel to run pulping plants. However, less than 2% of the available lignin has been utilized for producing specialty chemicals, such as dispersants, adhesives, surfactants, and other value-added products. The development of value-added lignin-derived co-products should help make second generation biorefineries and the paper industry more profitable by valorizing lignin. Another possible approach towards value-added applications is using lignin as a component in plastics. However, blending lignin with polymers is not simple because the polarity of lignin molecules results in strong self-interactions. Therefore, achieving in-depth insights on lignin characteristics and structure will help in accelerating the development of lignin-based products. Considering the multipurpose characteristics of lignin for producing value-added products, this review will shed light on the potential applications of lignin and lignin-based derivatives on polymeric composite production. Moreover, the challenges in lignin valorization will be addressed.

• Journal of Broadcast Engineering
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• v.24 no.1
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• pp.142-152
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• 2019

There is growing interest in ultra-high-resolution content that gives a more realistic sense of presence than existing broadcast content. However, in order to provide ultra-high-resolution contents in existing broadcast services, there are limitations in view angle and resolution of the image acquisition device. In order to solve this problem, many researches on stitching, which is an image synthesis method using a plurality of input devices, have been conducted. In this paper, we propose method of dynamic object based video stitching using minimal error seam in order to overcome the temporal invariance degradation of moving objects in the stitching process of horizontally oriented videos.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.167-168
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• 2022

Recently, starting with the permanent suspension of Gori 1 in Korea, the importance of the disposal of concrete structures in nuclear power plants has emerged, and environmental and safety are required to be proved accordingly. Safe radioactive waste disposal technology that immobilizes harmful radioactive elements, which are by-products of nuclear power, inside a solid matrix and recycling measures are needed to secure an efficient waste disposal space. This study was conducted to confirm whether recycled cement generated in the process of radioactive concrete treatment can be used as a solidifying material for radioactive waste treatment. In order to simulate the concrete exposed to radiation, aqueous solutions of Di-water, CsCl 1M, and CoCl₂ 1M were used as blending water at W/B 0.5. Tricalcium phosphate and Prussian blue were substituted with 5 wt.% based on the weight of recycled cement as a binder to improve solidification performance, and their hydration characteristic was analyzed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.9
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• pp.2458-2482
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• 2023

Medical image segmentation techniques based on convolution neural networks indulge in feature extraction triggering redundancy of parameters and unsatisfactory target localization, which outcomes in less accurate segmentation results to assist doctors in diagnosis. In this paper, we propose a multi-level semantic-rich encoding-decoding network, which consists of a Pooling-Conv-Former (PCFormer) module and a Cbam-Dilated-Transformer (CDT) module. In the PCFormer module, it is used to tackle the issue of parameter explosion in the conservative transformer and to compensate for the feature loss in the down-sampling process. In the CDT module, the Cbam attention module is adopted to highlight the feature regions by blending the intersection of attention mechanisms implicitly, and the Dilated convolution-Concat (DCC) module is designed as a parallel concatenation of multiple atrous convolution blocks to display the expanded perceptual field explicitly. In addition, MultiHead Attention-DwConv-Transformer (MDTransformer) module is utilized to evidently distinguish the target region from the background region. Extensive experiments on medical image segmentation from Glas, SIIM-ACR, ISIC and LGG demonstrated that our proposed network outperforms existing advanced methods in terms of both objective evaluation and subjective visual performance.

• Journal of the Korean Society of Clothing and Textiles
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• v.48 no.3
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• pp.397-416
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• 2024

This study investigated gender characteristics in contemporary virtual fashion design, focusing on avatars and genderless fashion in recent collections from Auroboros, Republiqe, Placebo Digital Fashion House, RTFKT, and Tribute. Employing content analysis within a theoretical framework of gender-related research, the study coded virtual avatars in terms of biological sex, appearance, and sociological perspectives. The results showed a preference for female-type avatars, through which androgynous aesthetics were embraced and traditional gender norms were challenged. Male-type avatars reflected experimentation with blending masculine elements, emphasizing inclusivity. Human-like avatars indicated a preference for designs that promoted inclusivity and, in the process, challenged binary classifications. The examined brands strategically capitalized on compromise, sensuality, and playfulness, thereby breaking away from traditional values to opt for more diverse styles. Genderless features combined elements from traditional men's and women's clothing, espousing sensuality and playful exaggeration. These findings signify a dynamic shift away from conventional gender standards to foster inclusivity and experimentation. They can serve as a reference for promoting creative strategies and design innovation, challenging the traditional gender perspective in the fashion industry. Implementing these strategies can lead to a more inclusive representation of fashion styles, encouraging critical thinking about gender norms.

• Applied Chemistry for Engineering
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• v.31 no.6
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• pp.596-602
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• 2020

Blending process of adhesive production has a cooling process to cool down the temperature of the solution which was heated up to 76 ℃ with a mineral insulated (MI) cable by 30 ℃ at room temperature. Using a MI cable in the adhesive production process makes the production inefficient because it takes about 10 h for the cooling process. If a jacketed vessel is used instead of the MI cable, it would shorten the cooling downtime without any additional cooling system by using cold water. However, there are various types of jacketed vessels, and thus the most suitable type should be found before set up. In this study, we designed the optimized jacketed vessel for the adhesive production process by calculating the cooling downtime, which impacts production efficiency, as a function of the jacket types using computational fluid dynamics. As a result, the cooling performance of the plain jacket was 32.7% superior to that of the half-pipe coil jacket with the same height. In addition, the plain jacket with 60% spiral baffle reduced the cooling downtime and operating time by 80.4% and 25.1%, respectively.

• Clean Technology
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• v.4 no.2
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• pp.54-60
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• 1998

Polyphenylvinylketone (PPVK) having a carbonyl group at the side chain was blended with polystyrene (PS) to investigate the effect of vinylketone polymers on the photodegradability of the blend as a function of U.V. irradiation time. Hydrogenated polyphenylvinylketone (PPVK(H)) which is made by hydrogenation of some of the carbonyl groups in PPVK was also blended with PS to check the role of carbonyl carbonyl group in the process of photodegradation. Photodegradability was also investigated for blends of PS with polymethylvinylketone (PMVK) and for copolymers of styrene and methylvinylketone (SMVK) to compare the effect of copolymerization versus blending on photodegradability. PPVK showed higher photodegradability than PPVK(H), which followed that the blends of PS with PPVK gave higher degradability than with PPVK(H). In view of the fact that PPVK(H) is a partially hydrogenated version of PPVK, carbonyl group was confirmed to be involved in the photodegradation mechanism. When polymethylvinylketone (PMVK) was blended with PS, this blend showed a higher degradability than PS/PPVK blend. Therefore the highest photodegradability was achieved when PS was blended with PMVK followed by PPVK and PPVK(H) in order. When SMVK was UV irradiated, it showed the highest photodegradability than any blends mentioned above. Therefore, copolymerization was proved to be the better means of photodegradation than blending.

• Polymer(Korea)
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• v.33 no.3
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• pp.191-197
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• 2009

We have investigated the effect of strong p-type organic semiconductor $F_4$-TCNQ-doped CuPc hole transport layer on the performance of p-i-n type bulk heterojunction photovoltaic device with ITO/PEDOT:PSS/CuPc: $F_4$-TCNQ(5 wt%)/CuPc:C60(blending ratio l:l)/C60/BCP/LiF/Al, architecture fabricated via vacuum deposition process, and have evaluated the J-V characteristics, short-circuit current ($J_{sc}$), open-circuit voltage($V_{oc}$), fill factor(FF), and power conversion efficiency(${\eta}_e$) of the device. By doping $F_4$-TCNQ into CuPc hole transport layer, increased absorption intensity in absorption spectra, uniform dispersion of organic molecules in the layer, surface uniformity of the layer, and enhanced injection currents improved the current photovoltaic device with power conversion efficiency(${\eta}_e$) of 0.16%, which is still low value compared to silicone solar cell indicating that many efforts should be made to improve organic photovoltaic devices.

• Polymer(Korea)
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• v.29 no.6
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• pp.565-570
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• 2005

Melt processing characteristics of nylon 6 (N6) has been investigated by controlling the melt viscosity in melt impregnation process. Calcium stearate (CaST) was introduced as a lubricant for N6 and the melt viscosity of N6 decreased with adding only 1 wt$\%$ of CaST. In addition, reactive blending with polycaprolactone (PCL) was carried out by lowering the melt viscosity in N6. It was found that the melt viscosity of N6 could be controlled and further melt viscosity drop could be obtained by applying phenyl phosphite (PP) and diphenyl phosphite (DPP) to enhance the transesterification between N6 and PCL. Our approaches show that the melt viscosity of N6 could be reduced without loss of thermal stability which is the critical problem in high temperature melt impregnation process of N6.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.1
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• pp.89-97
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• 2017

Butanol has an ability to improve the ignition quality due to its lower latent heat of vaporization; it has an advantage to reduce a volume of a fuel tank because its energy density is higher than that of ethanol. Also, butanol-diesel oil blending quality is good because butanol has an effect to prevent the phase-separation between two fuels. Even if the blended oil contains water, it can reduce the corrosion of the fuel line. Thus, it is possible to use butanol-diesel oil blended fuel in diesel engine without modification, and it may reduce the environment pollution due to NOx and particulate and the consumption of diesel oil. Therefore, some studies are being advanced whether butanol is adequate as an alternative fuel for diesel engines, and the results of the combustion and exhaust gas emission characteristics are being presented. Though the injection and spray characteristics of butanol are more important in diesel combustion, the has not yet dealt with the matter. In this study, the influence in which differences of physical properties between butanol and diesel oil may affect the injection and spray characteristics such as injection rate, penetration, spray cone angle, spray velocity and process of spray development were examined by using CRDI system, injection rate measuring device and spray visualization system. The results exhibited that the injection and macroscopic spray characteristics of two fuels were nearly the same.