• BMB Reports
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• v.49 no.10
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• pp.529-535
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• 2016

The NLRP3 inflammasome is activated by a variety of external or host-derived stimuli and its activation initiates an inflammatory response through caspase-1 activation, resulting in inflammatory cytokine IL-1β maturation and secretion. The NLRP3 inflammasome activation is a kind of innate immune response, most likely mediated by myeloid cells acting as a host defense mechanism. However, if this activation is not properly regulated, excessive inflammation induced by overactivated NLRP3 inflammasome can be detrimental to the host, causing tissue damage and organ dysfunction, eventually causing several diseases. Previous studies have suggested that mitochondrial damage may be a cause of NLRP3 inflammasome activation and autophagy, which is a conserved self-degradation process that negatively regulates NLRP3 inflammasome activation. Recently, mitochondria-selective autophagy, termed mitophagy, has emerged as a central player for maintaining mitochondrial homeostasis through the elimination of damaged mitochondria, leading to the prevention of hyperinflammation triggered by NLRP3 inflammasome activation. In this review, we will first focus on the molecular mechanisms of NLRP3 inflammasome activation and NLRP3 inflammasome-related diseases. We will then discuss autophagy, especially mitophagy, as a negative regulator of NLPP3 inflammasome activation by examining recent advances in research.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.5
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• pp.45-51
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• 1997

Low temperature activation of dopants which were doped using ion mass doping system in amorphous silicon(a-Si) thin films was investigated. With a 20.angs.-thick Ni film on top of the a-Si thin film, the activation temperature of dopants lowered to 500.deg. C. When the doping was performaed after the deposition of Ni thin film on the a-Si thin films (post-doping), the activation time was shorter than that of dopants mass, the activation time of the dopants doped by pre-doping method increased. It turned NiSi2 formation, while the decrease of activation time was mainly due to the enhancement of the NiSi2 formation by mixing of Ni and a-Si at the interface of Ni and a -Si thin during the ion doping process.

• Korean Journal of Materials Research
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• v.30 no.7
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• pp.327-332
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• 2020

Laser induced surface activation (LISA) technology requires refined selection of process variables to fabricate conductive microcircuits on a general polymer material. Among the process variables, laser mode is one of the crucial factors to make a reliable conductor pattern. Here we compare the continuous wave (CW) laser mode with the pulse wave (PW) laser mode through determination of the surface roughness and circuit accuracy. In the CW laser mode, the surface roughness is pronounced during the implementation of the conductive circuit, which results in uneven plating. In the PW laser mode, the surface is relatively smooth and uniform, and the formed conductive circuit layer has few defects with excellent adhesion to the polymer material. As a result of a change of laser mode from CW to PW, the value of Ra of the polymer material decreases from 0.6 ㎛ to 0.2 ㎛; the value of Ra after the plating process decreases from 0.8 ㎛ to 0.4 ㎛, and a tight bonding force between the polymer source material and the conductive copper plating layer is achieved. In conclusion, this study shows that the PW laser process yields an excellent conductive circuit on a polymeric material.

• Journal of Environmental Science International
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• v.29 no.12
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• pp.1205-1211
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• 2020

In this study, the applicability of reduction-oxidation-linked treatment was evaluated for nitrobenzene and a by-product by analyzing the reaction kinetics. Nitrobenzene showed very low reactivity to persulfate that was activated using various methods. Nitrobenzene effectively reacted through the reduction process using Zero-Valent Iron (ZVI). However, aniline, a toxic substance, was produced as a by-product. Reduction-oxidation-linked treatment is a method that can allow the oxidative degradation of aniline after reducing nitrobenzene to aniline. The experimental results show improved reactivity and complete decomposition of the by-product. Improved reactivity and decomposition of the by-product were observed even under conditions in which the reduction-oxidation reaction was induced simultaneously. No activator was injected for persulfate activation in the process of reducing oxidant linkage, and the activation reaction was induced by ferrous iron eluted from the ZVI. This indicates that this method can be implemented relatively simply.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.616-625
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• 2021

Deep neural networks are an approximation method that approximates an arbitrary function to a linear model and then repeats additional approximation using a nonlinear active function. In this process, the method of evaluating the performance of approximation uses the loss function. Existing in-depth learning methods implement approximation that takes into account loss functions in the linear approximation process, but non-linear approximation phases that use active functions use non-linear transformation that is not related to reduction of loss functions of loss. This study proposes parametric activation functions that introduce scale parameters that can change the scale of activation functions and location parameters that can change the location of activation functions. By introducing parametric activation functions based on scale and location parameters, the performance of nonlinear approximation using activation functions can be improved. The scale and location parameters in each hidden layer can improve the performance of the deep neural network by determining parameters that minimize the loss function value through the learning process using the primary differential coefficient of the loss function for the parameters in the backpropagation. Through MNIST classification problems and XOR problems, parametric activation functions have been found to have superior performance over existing activation functions.

• Korean Management Science Review
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• v.34 no.3
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• pp.43-60
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• 2017

This study empirically examined the differences in degrees of product or process innovations according to the activation forms of all knowledge management (KM) processes (i.e., socialization, internalization, externalization, and combination), which are influenced by the usage patterns of management control systems (MCS)(i.e., interactive and diagnostic usage patterns). We empirically investigated and identified the links among usage patterns of MCS, the activation forms of KM processes, and the kinds of innovation promoted. Under high competitive conditions, it was found that the interactive usage of MCS is relatively more preferred and enhanced. However, when environmental uncertainty is high, it was shown that the diagnostic use of MCS is more emphasized. Thus, it is evident that the use patterns of MCS are determined by environmental conditions. From the results of this study, it was suggested that under high interactive use of MCS, the activation of socialization and internalization is more enhanced than the facilitation of externalization. It was also observed that when both interactive and diagnostic usage of MCS are high, KM processes are more activated and strengthened. The results indicated that under high activation of KM processes, product innovation as well as process innovation are more frequently occurred. Finally, the results of this study suggested that according to the levels of innovation openness, major innovations are more frequently occurred and promoted than minor innovations.

• Journal of Science Education
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• v.46 no.1
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• pp.30-39
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• 2022

The purpose of this study is to compare and analyze secondary school student's brain activity on assimilation, conflict, and accommodation processes of self-regulation. The self-regulation task was presented a biological phylogenetic task, and the brain activity was measured and analyzed with fNIRS. As a result, a significant activation was found in the left DLPFC, OFC, and FP regions in the conflict process compared to the assimilation process, and a significant activation was found in DLPFC and VLPFC in the accommodation process. As the age increase, the DLPFC also increases in the conflict process and VLPFC increases in the assimilation process. In addition, comparing conflict and accommodation process, the 7th grade students show a significant brain activity in the right VLPFC, the 9th grade students show significant brain activity in the left FP and DLPFC areas in the accommodation process. However, the 11th grade students did not show any significant brain activity at this process. These results presumably show that the neurological research method could be applied to educational research in cognitive activity and classroom instructional situation.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.103-110
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• 2014

Sisal fiber, an agricultural resource abundantly available in china, has been used as raw material to prepare activated carbon with high surface area and huge pore volume by chemical activation with zinc chloride. The orthogonal test was designed to investigate the influence of zinc chloride concentration, impregnation ratio, activation temperature and activation time on preparation of activated carbon. Scanning electron micrograph, Thermo-gravimetric, $N_2$-adsorption isotherm, mathematical models such as t-plot, H-K equation, D-R equation and BJH methods were used to characterize the properties of the prepared carbons and the activation mechanism was discussed. The results showed that $ZnCl_2$ changed the pyrolysis process of sisal fiber. Characteristics of activated carbon are: BET surface area was $1628m^2/g$, total pore volume was $1.316m^3/g$ and ratio of mesopore volume to total pore volume up to 94.3%. These results suggest that sisal fiber is an attractive source to prepare mesoporous high-capacity activated carbon by chemical activation with zinc chloride.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.58-61
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• 2023

The activation process is essential for PEMFC to improve initial performance. The most commonly used activation method is a voltage change (load change) method, which may accompany degradation of the electrode catalyst if excessively performed. In many activation processes, the voltage change range is activated in a wide range from 0.4 V to OCV, and research is needed to reduce the voltage change range in order to prevent electrode catalyst degradation and shorten the activation time. Therefore, in this study, when the activation voltage range was 0.4~0.6 V, 0.4~0.8 V, and 0.4~OCV, we tried to research and develop an effective activation method by analyzing the performance and characteristics of the electrode and polymer membrane. The performance improvement was the lowest in the activation with a wide voltage range from 0.4 V to the highest OCV, and the performance decreased by 10% when activated for 56 cycles. The 0.4~0.6 V activation cycle showed the highest performance improvement up to 20% and the smallest decrease in performance due to overactivation, indicating that it is optimal method.

• Carbon letters
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• v.20
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• pp.32-38
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• 2016

In this study, cellulose nanoplates (CNPs) were fabricated using cellulose nanocrystals obtained from commercial microcrystalline cellulose (MCC). Their pyrolysis behavior and the characteristics of the product carbonaceous materials were investigated. CNPs showed a relatively high char yield when compared with MCC due to sulfate functional groups introduced during the manufacturing process. In addition, pyrolyzed CNPs (CCNPs) showed more effective chemical activation behavior compared with MCC-induced carbonaceous materials. The activated CCNPs exhibited a microporous carbon structure with a high surface area of 1310.6 m²/g and numerous oxygen heteroatoms. The results of this study show the effects of morphology and the surface properties of cellulose-based nanomaterials on pyrolysis and the activation process.