Swarm Intelligence-based Power Allocation and Relay Selection Algorithm for wireless cooperative network

( Yaxin Xing ),( Yueyun Chen ),( Chen Lv ),( Zheng Gong ),( Ling Xu ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.3

Cooperative communications can significantly improve the wireless transmission performance with the help of relay nodes. In cooperative communication networks, relay selection and power allocation are two key issues. In this paper, we propose a relay selection and power allocation scheme RS-PA-PSACO (Relay Selection-Power Allocation-Particle Swarm Ant Colony Optimization) based on PSACO (Particle Swarm Ant Colony Optimization) algorithm. This scheme can effectively reduce the computational complexity and select the optimal relay nodes. As one of the swarm intelligence algorithms, PSACO which combined both PSO (Particle Swarm Optimization) and ACO (Ant Colony Optimization) algorithms is effective to solve non-linear optimization problems through a fast global search at a low cost. The proposed RS-PA-PSACO algorithm can simultaneously obtain the optimal solutions of relay selection and power allocation to minimize the SER (Symbol Error Rate) with a fixed total power constraint both in AF (Amplify and Forward) and DF (Decode and Forward) modes. Simulation results show that the proposed scheme improves the system performance significantly both in reliability and power efficiency at a low complexity.

User-Controlled Layout Editing with Neural Style Transfer

Yaxin Wang,Kyubeom Han(한규범),Jaeyoon Kim(김재윤),Sung-Eui Yoon(윤성의) 한국컴퓨터그래픽스학회 2023 한국컴퓨터그래픽스학회 학술대회 Vol.2023 No.7

Ginsenoside Rb1 Inhibits Doxorubicin-Triggered H9C2 Cell Apoptosis via Aryl Hydrocarbon Receptor

( Yaxin Zhang ),( Yuguang Wang ),( Zengchun Ma ),( Qiande Liang ),( Xianglin Tang ),( Hongling Tan ),( Chengrong Xiao ),( Yue Gao ) 한국응용약물학회 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.2

Doxorubicin (DOX) is a highly effective chemotherapeutic agent; however, the dose-dependent cardiotoxicity associated with DOX significantly limits its clinical application. In the present study, we investigated whether Rb1 could prevent DOX-induced apoptosis in H9C2 cells via aryl hydrocarbon receptor (AhR). H9C2 cells were treated with various concentrations (- μM) of Rb1. AhR, CYP1A protein and mRNA expression were quantified with Western blot and real-time PCR analyses. We also evaluated the expression levels of caspase-3 to assess the anti-apoptotic effects of Rb1. Our results showed that Rb1 attenuated DOX-induced cardiomyocytes injury and apoptosis and reduced caspase-3 and caspase-8, but not caspase-9 activity in DOX-treated H9C2 cells. Meanwhile, pre-treatment with Rb1 decreased the expression of caspase-3 and PARP in the protein levels, with no effects on cytochrome c, Bax, and Bcl-2 in DOX-stimulated cells. Rb1 markedly decreased the CYP1A1 and CYP1A2 expression induced by DOX. Furthermore, transfection with AhR siRNA or pre-treatment with AhR antagonist CH-223191 significantly inhibited the ability of Rb1 to decrease the induction of CYP1A, as well as caspase-3 protein levels following stimulation with DOX. In conclusion, these findings indicate that AhR plays an important role in the protection of Ginsenoside Rb1 against DOX-triggered apoptosis of H9C2 cells.

Ginsenoside Rb1 Inhibits Doxorubicin-Triggered H9C2 Cell Apoptosis via Aryl Hydrocarbon Receptor

Zhang, Yaxin,Wang, Yuguang,Ma, Zengchun,Liang, Qiande,Tang, Xianglin,Tan, Hongling,Xiao, Chengrong,Gao, Yue The Korean Society of Applied Pharmacology 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.2

Doxorubicin (DOX) is a highly effective chemotherapeutic agent; however, the dose-dependent cardiotoxicity associated with DOX significantly limits its clinical application. In the present study, we investigated whether Rb1 could prevent DOX-induced apoptosis in H9C2 cells via aryl hydrocarbon receptor (AhR). H9C2 cells were treated with various concentrations ($-{\mu}M$) of Rb1. AhR, CYP1A protein and mRNA expression were quantified with Western blot and real-time PCR analyses. We also evaluated the expression levels of caspase-3 to assess the anti-apoptotic effects of Rb1. Our results showed that Rb1 attenuated DOX-induced cardiomyocytes injury and apoptosis and reduced caspase-3 and caspase-8, but not caspase-9 activity in DOX-treated H9C2 cells. Meanwhile, pre-treatment with Rb1 decreased the expression of caspase-3 and PARP in the protein levels, with no effects on cytochrome c, Bax, and Bcl-2 in DOX-stimulated cells. Rb1 markedly decreased the CYP1A1 and CYP1A2 expression induced by DOX. Furthermore, transfection with AhR siRNA or pre-treatment with AhR antagonist CH-223191 significantly inhibited the ability of Rb1 to decrease the induction of CYP1A, as well as caspase-3 protein levels following stimulation with DOX. In conclusion, these findings indicate that AhR plays an important role in the protection of Ginsenoside Rb1 against DOX-triggered apoptosis of H9C2 cells.

Persistent free radicals in carbon-based materials on transformation of refractory organic contaminants (ROCs) in water: A critical review

Qin, Yaxin,Li, Guiying,Gao, Yanpeng,Zhang, Lizhi,Ok, Yong Sik,An, Taicheng Elsevier 2018 Water research Vol.137 No.-

<P><B>Abstract</B></P> <P>With the increased concentrations and kinds of refractory organic contaminants (ROCs) in aquatic environments, many previous reviews systematically summarized the applications of carbon-based materials in the adsorption and catalytic degradation of ROCs for their economically viable and environmentally friendly behavior. Interestingly, recent studies indicated that carbon-based materials in natural environment can also mediate the transformation of ROCs directly or indirectly due to their abundant persistent free radicals (PFRs). Understanding the formation mechanisms of PFRs in carbo-based materials and their interactions with ROCs is essential to develop their further applications in environment remediation. However, there is no comprehensive review so far about the direct and indirect removal of ROCs mediated by PFRs in amorphous, porous and crystalline carbon-based materials. The review aims to evaluate the formation mechanisms of PFRs in carbon-based materials synthesized through pyrolysis and hydrothermal carbonization processes. The influence of synthesis conditions (temperature and time) and carbon sources on the types as well as the concentrations of PFRs in carbon-based materials are also discussed. In particular, the effects of metals on the concentrations and types of PFRs in carbon-based materials are highlighted because they are considered as the catalysts for the formation of PFRs. The formation mechanisms of reactive species and the further transformation mechanisms of ROCs are briefly summarized, and the surface properties of carbon-based materials including surface area, types and number of functional groups, etc. are found to be the key parameters controlling their activities. However, due to diversity and complexity of carbon-based materials, the exact relationships between the activities of carbon-based materials and PFRs are still uncertain. Finally, the existing problems and current challenges for the ROCs transformation with carbon-based materials are also pointed out.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Abundant of PFRs formed in carbon-based materials during the synthesis process. </LI> <LI> The PFRs types and concentrations affected by synthesis conditions. </LI> <LI> The PFRs can activate oxidants and reductants to degrade organic contaminants. </LI> <LI> The PFRs can directly react with organic contaminants. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Activation strategies of metal-organic frameworks for the sorption of reduced sulfur compounds

Deng, Yaxin,Vellingiri, Kowsalya,Kim, Ki-Hyun,Boukhvalov, Danil W.,Philip, Ligy Elsevier 2018 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.350 No.-

<P><B>Abstract</B></P> <P>In order to investigate the possible options to improve the pore properties of metal-organic frameworks (MOFs), the sorptive capacity of MOF-199 was assessed based on the two contrasting activation approaches (i.e., ‘chemical (<B>C</B>)’ and ‘thermal (<B>T</B>)’ activation) against four reduced sulfur (S) compounds <B>(</B>RSCs: H<SUB>2</SUB>S, CH<SUB>3</SUB>SH, (CH<SUB>3</SUB>)<SUB>2</SUB>S (DMS), and CH<SUB>3</SUB>SSCH<SUB>3</SUB> (DMDS)). In order to represent the pristine (<B>C1</B>) and chemically activated forms of MOF-199 (<B>C2</B>), the pores were filled by N,N′-dimethylformamide (DMF) (i.e., as synthesized) and dichloromethane (CH<SUB>2</SUB>Cl<SUB>2</SUB>), respectively. For comparative purpose, these samples were further subject to thermal treatment (150 °C under 100 mL min<SUP>−1</SUP>) and named as <B>T1</B> and <B>T2</B>, respectively. The combined effects of chemical/thermal activation were found to be most effective to enhance the sorption capacity of MOF-199. (Note that such advantage was not evident when treated by chemical activation only.) Overall, the relative ordering of sorption capacities between four different types of MOF-199, when tested against diverse S compounds, was found to be DMDS > CH<SUB>3</SUB>SH > H<SUB>2</SUB>S > DMS. The mechanism for such sorption patterns was ascribed to two major competing interactions: a) S-Cu for lighter S and b) –CH<SUB>3</SUB> group (in S compound) and aromatic ring (in MOF ligand) for heavier S. This synergetic effect was also confirmed by both theoretically (density functional theory (DFT)) and experimentally (Fourier Transform Infrared (FTIR) spectroscopy analysis). As such, MOF-199 prepared through both chemical and thermal treatments was identified as an efficient sorbent to capture S compounds even in ambient conditions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> It is a delicate goal to develop an efficient tool to control reduced sulfur compounds (RSCs). </LI> <LI> The feasibility of chemical/solvent and thermal activation of MOF-199 was tested against RSCs. </LI> <LI> The sorption properties of MOF-199 were then explored against their mixtures. </LI> <LI> The sorption capacities of activated MOF-199 were compared in terms of breakthrough volume. </LI> <LI> The processes controlling the sorption of RSCs to MOFs were analyzed from various respects. </LI> </UL> </P>

재한 중국인 유학생의 문화적응 스트레스와 대학생활적응의 관계에서 희망의 매개효과

유아신(LIU, YAXIN),최아론(Choi, A-ron) 한국교육치료학회 2021 교육치료연구 Vol.13 No.1

본 연구는 전라북도 지역 소재의 대학교에 재학중인 중국인 유학생 497명을 대상으로 문화적응 스트레스와 대학생활적응의 관계에서 희망의 매개효과를 살펴보았다. 인구통계학적 특성에 따른 대학생활적응의 차이가 있는지를 확인하기 위해 독립표본 t-test와 분산분석을 실시하였고 사후검정으로 Scheffe을 사용하였다. 연구 검증을 위해 연구변인들 간의 상관관계를 분석하고, Process Macro를 통해 매개효과를 검증하였다. 그 결과 첫째, 중국 유학생의 대학생활적응은 나이, 체류기간, 신분, 한국어 능력에 따라 유의미한 차이를 보였지만 성별에 따라서는 유의미한 차이를 보이지 않았다. 둘째, 문화적응 스트레스는 희망, 대학생활적응과 유의미한 부적 상관을 보였으나 희망과 대학생활적응은 유의미한 정적상관을 보였다. 셋째, 중국 유학생의 문화적응 스트레스와 대학생활적응의 관계에서 희망의 부분 매개효과를 검증하였다. 이와 같은 본 연구의 결과는 중국인 유학생이 어느 부분에서 주된 스트레스를 받고 있는지 확인하여 스트레스 수준을 낮추고 보다 더 효율적인 대학생활을 할 수 있도록 적응 수준을 향상시킬 수 있는 개인이나 집단상담 프로그램 개발에 활용하고자 한다. This study examined the mediation effect of hope in the relationship between acculturative stress and university life adaptation among 497 Chinese students based in Jeollabuk-do. Independent sample t-test and analysis of variance were conducted to check if there were differences in university life adaptation according to demographic characteristics, and Scheffe was used as a follow-up test. Correlation among research variables was analyzed for research verification, and the mediation effect was verified through Process Macro. The results of the study are as follows. Firstly, the adjustment of Chinese students to university life in Korea showed significant differences depending on their age, length of stay, status, and Korean language ability. Still, there was no significant difference depending on the gender of Chinese students in Korea. Secondly, the cultural adaptation stress showed a significant amulet correlation with hope, university student adaptation, and a significant amulet. However, there was a significant static correlation between hope and university life adaptation. Thirdly, the partial mediation effect of hope was verified in the relationship between cultural adaptation stress and university life adaptation of Chinese students in Korea. The results of this study will be used to develop counseling programs that can help Chinese students in Korea experience major stress and improve their level of adaptation so that they can lower their stress levels and have a more efficient college life.

An Enhanced Model Predictive Controller for Quadrotor Attitude Quick Adjustment with Input Constraints and Disturbances

Bin Li,Yaxin Wang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.2

In this paper, a fuzzy model predictive controller based on disturbance observer is proposed for attitude control of quadrotor Unmanned Aerial Vehicle (UAV) subject to input constraints and disturbances. The proposed algorithm consists of a fuzzy predictive controller based on a T-S fuzzy model and a disturbance observer. FMPC can handle the constraints of the system and disturbance observer is designed to compensate the disturbance effect. In this work, the Takagi-Sugeno fuzzy model is used for the predictive controller, which is used to more approximate the nonlinear model to obtain a faster convergence speed. To test the effectiveness of the proposed algorithm, simulations for the quadrotor are implemented and the tracking performance among the proposed method, existing linear predictive controller and PID algorithm is compared with each other. Both simulation and experiment results show the effectiveness of using fuzzy model and disturbance observer.

Graphene Enhanced Electrical Properties of Polyethylene Blends for High-Voltage Insulation

Zuojun Wei,Yaxin Hou,Chen Jiang,Haiyan Liu,Xiangrong Chen,Anyun Zhang,Yingxin Liu 대한금속·재료학회 2019 ELECTRONIC MATERIALS LETTERS Vol.15 No.5

Graphene as a novel additive in low density polyethylene (LDPE), high density polyethylene–low density polyethylene blend(10%HDPE–LDPE) and polypropylene–low density polyethylene blend (10%PP–LDPE), is investigated for promising ecofriendlyinsulating materials in high voltage cables. The composites with graphene amounts of 0, 0.002 wt%, 0.02 wt%,and 0.2 wt% are prepared by the solution mixing method. With attempt to disclose the structure–property relationships, thecomposites are extensively characterized by physical techniques including Fourier transform infrared spectroscopy, X-raydiffraction, atomic force microscopy, transmission electron microscopy, scanning electron microscopy, thermogravimetricanalysis and differential scanning calorimetry, and electrical measurements including electrical treeing, direct current conductivityand space charge distributions. Results show that graphene can significantly enhances the thermal stability of LDPEand 10%PP–LDPE, slightly decrease the degree of crystallinity, change the size of the crystal diameters, and improve thephase distribution of the polymer blends. Consequently, graphene can prolong the electrical tree initiation time and blockthe extension of electrical tree. Besides, it can modulate the trap distributions, which will further change the conductivityand ability to suppress space charge accumulations. This excellent performance of graphene could be attributed to its goodexfoliation, uniform dispersion and outstretched morphology in the polymer matrix, as well as its strong ability to captureelectrons.

Numerical analysis of thermal dynamics and mixing performance in the blade-type static mixers

Yanfang Yu,Yaxin Chen,Huibo Meng,Yunjuan Yao,Dongzhou Liu,Jianhua Wu 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.7

The turbulent thermal dynamics and mixing performance of kenics static mixer (KSM), lightnin static mixer (LSM) and Q-type static mixer (QSM) were numerically simulated with uniform heat flux within the range of Reynolds numbers (Re) between 6000 and 30000. The numerical predictions of Nusselt number (Nu) and friction coefficient (f) in KSM were well consistent with the experimental data. The dean vortices, thermal resistance, entropy generation and field synergy were fully analyzed to obtain the enhancement mechanism of heat transfer performance. The synergy performance between temperature gradient and flow field firstly decreased and then increased and are superior to that of KSM with increasing Re. With the same Re, the entropy generation rates of LSM are 0.93-0.94 times that of QSM. LSM is a better alternative consideration for convection mixing and heat transfer enhancement. Two new relationships between Nu and f under different dimensionless uniform heat flux are obtained.