• Applied Chemistry for Engineering
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• v.22 no.6
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• pp.672-678
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• 2011

In this work, carbon fibers were electrolessly Ni-plated in order to investigate the effect of metal plating on the electromagnetic shielding effectiveness (EMI-SE) of Ni-coated carbon fibers-reinforced epoxy matrix composites. The surfaces of carbon fibers were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Electric resistance of the composites was tested using a 4-point-probe electric resistivity tester. The EMI-SE of the composites was evaluated by means of the reflection and adsorption methods. From the results, it was found that the EMI-SE of the composites enhanced with increasing Ni plating time and content. In high frequency region, the EMI-SE didn't show further increasing with high Ni content (Ni-CF 10 min) compared to the Ni-CF 5 min sample. In conclusion, Ni content on the carbon fibers can be a key factor to determine the EMI-SE of the composites, but there can be an optimized metal content at a specific electromagnetic frequency region in this system.

• Journal of Popular Narrative
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• v.26 no.3
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• pp.87-120
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• 2020

The study noted the characteristics of the web novel's 'Book Travel' motif, which reflects the characteristics of popular culture content, which is free to use familiar genre grammar or code. The imagination of the main character entering the work he read in the real world is a reinterpretation of the existing genre grammar of the web novel, and studying the motif is meaningful in reviewing the intertext of the genre. This motif, summarized as 'Book Travel' differs from other genres in the romance fantasy genre, which can also be used to reveal the gender characteristics of the genre. The study noted that the 'Book Travel' motif was born from an interactive interpretation of existing narratives, thus having a affinity with dimensional shift, regression, and alternative historical objects, and referring to the writing norms of Fanfiction. Through this, it was predicted that the re-combination of existing narratives and interference between genres would continue in the future. Next, the original move in the romance fantasy genre was seen as quite conservative and revealing the logic of self-improvement even though people around him became the main characters and overthrew the narrative. The characters should use their knowledge of the future of the real world to fight in a world of survival where destruction has been predicted. The appearance of an ethical and self-help subject is interesting, but on the other hand, I could look at conservatism in that romance is a way of survival and achievement of characters. The research is meaningful in that it reviewed the characteristics of the original transfer motif, which started fairly quickly in the romance fantasy genre, and reviewed its appearance background and characteristics. There was a limit to the collection of physical works and limited platform. The above limits are intended to be supplemented by further reviewing and supplementing later works.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.7
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• pp.1951-1975
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• 2023

Recent advances in Cognitive Radio Networks (CRN) have elevated them to the status of a critical instrument for overcoming spectrum limits and achieving severe future wireless communication requirements. Collaborative spectrum sensing is presented for efficient channel selection because spectrum sensing is an essential part of CRNs. This study presents an innovative cooperative spectrum sensing (CSS) model that is built on the Firefly Algorithm (FA), as well as machine learning artificial neural networks (ANN). This system makes use of user grouping strategies to improve detection performance dramatically while lowering collaboration costs. Cooperative sensing wasn't used until after cognitive radio users had been correctly identified using energy data samples and an ANN model. Cooperative sensing strategies produce a user base that is either secure, requires less effort, or is faultless. The suggested method's purpose is to choose the best transmission channel. Clustering is utilized by the suggested ANN-FA model to reduce spectrum sensing inaccuracy. The transmission channel that has the highest weight is chosen by employing the method that has been provided for computing channel weight. The proposed ANN-FA model computes channel weight based on three sets of input parameters: PU utilization, CR count, and channel capacity. Using an improved evolutionary algorithm, the key principles of the ANN-FA scheme are optimized to boost the overall efficiency of the CRN channel selection technique. This study proposes the Artificial Neural Network with Firefly Algorithm (ANN-FA) for cognitive radio networks to overcome the obstacles. This proposed work focuses primarily on sensing the optimal secondary user channel and reducing the spectrum handoff delay in wireless networks. Several benchmark functions are utilized We analyze the efficacy of this innovative strategy by evaluating its performance. The performance of ANN-FA is 22.72 percent more robust and effective than that of the other metaheuristic algorithm, according to experimental findings. The proposed ANN-FA model is simulated using the NS2 simulator, The results are evaluated in terms of average interference ratio, spectrum opportunity utilization, three metrics are measured: packet delivery ratio (PDR), end-to-end delay, and end-to-average throughput for a variety of different CRs found in the network.

• Korean Journal of Construction Engineering and Management
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• v.25 no.4
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• pp.24-33
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• 2024

Recently, as smart construction has become more active, construction companys are evaluating their smart construction capabilities in order to transform into smart construction companies. However, the revitalization of smart construction doesn't only apply to construction companies, the level of utilization of all participants, including owners, designers, construction project managers, and construction company, must be improved. Therefore, this study aims to present a model that evaluate the building information modeling (BIM) utilization level for measuring the BIM utilization level of construction management companies in executing construction project management. In this study, an AHP questionnaire survey targeting BIM practitioners to calculate the weight of each BIM utilization item and score it to construct evaluation model and evaluate it by applying it to construction management companies are conducted. As a result of the evaluation using model, there were differences between companies in the number of BIM users, and in the qualitative evaluation, it is mainly used for interference review, constructability review, and design change management. Therefore, in order to revitalize BIM, it is believed that it is necessary to strengthen BIM utilization ability through separate training for construction manager (CMr) and to present clear utilization standards and scope of work for BIM utilization in performing construction management tasks. Consequently, evaluating more construction management companies using the model presented in this study will result in the transition of CM companies to smart construction and revitalization of BIM adoption.

• Journal of Ginseng Research
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• v.48 no.5
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• pp.494-503
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• 2024

Background: With the prevalence of dietary supplements, the use of combinations of herbs and drugs is gradually increasing, together with the risk of drug interactions. In our clinical work, we unexpectedly found that the combination of Panax notoginseng and warfarin, which are herbs that activate blood circulation and remove blood stasis, showed antagonistic effects instead. The purpose of this study was to evaluate the drug interaction between Panax notoginseng saponins (PNS) and warfarin, the main active ingredient of Panax notoginseng, and to explore the interaction mechanism. Methods: The effects and mechanisms of PNS on the pharmacodynamics and pharmacokinetics of warfarin were explored mainly in Sprague-Dawley rats and HepG2 cells. Elisa was used to detect the concentrations of coagulation factors, HPLC-MS to detect the blood concentrations of warfarin in rats, immunoblotting was employed to examine protein levels, qRT-PCR to detect mRNA levels, cellular immunofluorescence to detect the localization of NR1I3, and dual luciferase to verify the binding of miR-214-3p and NR1I3. Results: PNS significantly accelerated warfarin metabolism and reduced its efficacy, accompanied by increased expression of NR1I3 and CYP2C9. Interference with NR1I3 rescued the accelerated metabolism of warfarin induce by PNS co-administration. In addition, we demonstrated that PNS significantly reduced miR-214-3p expression, whereas miR-214-3p overexpression reduced NR1I3 and CYP2C9 expression, resulting in a weakened antagonistic effect of PNS on warfarin. Additionally, we found that miR-214-3p bound directly to NR1I3 3'-UTR and significantly downregulated NR1I3 expression. Conclusion: Our study demonstrated that PNS accelerates warfarin metabolism and reduces its pharmacodynamics by downregulating miR-214-3p, leading to increased expression of its target gene NR1I3, these findings provide new insights for clinical drug applications to avoid adverse effects.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.3
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• pp.46-55
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• 2016

This work proposes a 13b 100MS/s 45nm CMOS ADC with a high dynamic performance for IF-domain high-speed signal processing systems based on a four-step pipeline architecture to optimize operating specifications. The SHA employs a wideband high-speed sampling network properly to process high-frequency input signals exceeding a sampling frequency. The SHA and MDACs adopt a two-stage amplifier with a gain-boosting technique to obtain the required high DC gain and the wide signal-swing range, while the amplifier and bias circuits use the same unit-size devices repeatedly to minimize device mismatch. Furthermore, a separate analog power supply voltage for on-chip current and voltage references minimizes performance degradation caused by the undesired noise and interference from adjacent functional blocks during high-speed operation. The proposed ADC occupies an active die area of $0.70mm^2$, based on various process-insensitive layout techniques to minimize the physical process imperfection effects. The prototype ADC in a 45nm CMOS demonstrates a measured DNL and INL within 0.77LSB and 1.57LSB, with a maximum SNDR and SFDR of 64.2dB and 78.4dB at 100MS/s, respectively. The ADC is implemented with long-channel devices rather than minimum channel-length devices available in this CMOS technology to process a wide input range of $2.0V_{PP}$ for the required system and to obtain a high dynamic performance at IF-domain input signal bands. The ADC consumes 425.0mW with a single analog voltage of 2.5V and two digital voltages of 2.5V and 1.1V.