Memory Event-triggered Sliding Mode Control for UAV Formation Under Communication Delay and Wake Interferences

Ming-Fei Ji,Tao Li,Shu-Min Fei,Xian-Lin Zhao 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.3

This paper studies the formation control for unmanned aerial vehicles (UAVs) under communicationdelay and wake disturbances, in which the inner-loop and outer-loop control strategy is adopted. Firstly, as for thedynamical models of follower UAVs, the wake interferences are considered and their influences are respectivelyestimated by using the sliding model disturbance observers (SMDOs). Secondly, since the outer-loop informationin the UAVs exchanges via communication network, by adding an internal dynamic variable, an adaptive memorybased event-triggered mechanism (METM) is proposed to alleviate transmission burden with maintaining idealcontrol performance. Thirdly, by using the designed METM and an intermediate vector, a sliding mode controller isderived to accomplish the desired control target, which can compensate the communication delay in control input. Fourthly, as for the overall closed-loop system, a sufficient condition on asymptotical stability is established and aco-design method of checking the triggering parameters and controller gains is expressed in term of linear matrixinequalities (LMIs). Moreover, in order to tackle the wake interferences of the inner-loop, an adaptive attitudetracking controller is put forward to ensure the bounded stability of tracking errors by solving the reference signal. Finally, a simulated example is exploited to illustrate the validity of the proposed scheme.

Moth-Flame Optimization-Based Maximum Power Point Tracking for Photovoltaic Systems Under Partial Shading Conditions

Ji-Ying Shi,Deng-Yu Zhang,Fei Xue,Ya-Jing Li,Wen Qiao,Wen-Jing Yang,Yi-Ming Xu,Ting Yang 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.5

This paper presents a moth-flame optimization (MFO)-based maximum power point tracking (MPPT) method for photovoltaic (PV) systems. The MFO algorithm is a new optimization method that exhibits satisfactory performance in terms of exploration, exploitation, local optima avoidance, and convergence. Therefore, the MFO algorithm is quite suitable for solving multiple peaks of PV systems under partial shading conditions (PSCs). The proposed MFO-MPPT is compared with four MPPT algorithms, namely the perturb and observe (P&O)-MPPT, incremental conductance (INC)-MPPT, particle swarm optimization (PSO)-MPPT and whale optimization algorithm (WOA)-MPPT. Simulation and experiment results demonstrate that the proposed algorithm can extract the global maximum power point (MPP) with greater tracking speed and accuracy under various conditions.

Why Students do not Respond to NAEP Reading Questions: The Relationship Between Students` Response Patterns And Reading Motivation

( Ji Yeon Hong ),( Fei Ming Li ),( Sun Joo Cho ),( Paul A. Schutz ),( Allan S. Cohen ) 서울대학교 국어교육과 2006 先淸語文 Vol.34 No.-

DTSTM: Dynamic Tree Style Trust Measurement Model for Cloud Computing

( Zhen-ji Zhou ),( Li-fa Wu ),( Zheng Hong ),( Ming-fei Xu ),( Fan Pan ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.1

In cloud computing infrastructure, current virtual machine trust measurement methods have many shortcomings in dynamism, security and concurrency. In this paper, we present a new method to measure the trust of virtual machine. Firstly, we propose “behavior trace” to describe the state of virtual machine. Behavior trace is a sequence of behaviors. The measurement of behavior trace is conducted on the basis of anticipated trusted behavior, which not only ensures security of the virtual machine during runtime stage but also reduces complexity of the trust measurement. Based on the behavior trace, we present a Dynamic Tree Style Trust Measurement Model (DTSTM). In this model, the measurement of system domain and user domain is separated, which enhances the extensibility, security and concurrency of the measurement. Finally, based on System Call Interceptor (SCI) and Virtual Machine Introspection (VMI) technology, we implement a DTSTM prototype system for virtual machine trust measurement. Experimental results demonstrate that the system can effectively verify the trust of virtual machine and requires a relatively low performance overhead.

Moth-Flame Optimization-Based Maximum Power Point Tracking for Photovoltaic Systems Under Partial Shading Conditions

Shi, Ji-Ying,Zhang, Deng-Yu,Xue, Fei,Li, Ya-Jing,Qiao, Wen,Yang, Wen-Jing,Xu, Yi-Ming,Yang, Ting The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.5

This paper presents a moth-flame optimization (MFO)-based maximum power point tracking (MPPT) method for photovoltaic (PV) systems. The MFO algorithm is a new optimization method that exhibits satisfactory performance in terms of exploration, exploitation, local optima avoidance, and convergence. Therefore, the MFO algorithm is quite suitable for solving multiple peaks of PV systems under partial shading conditions (PSCs). The proposed MFO-MPPT is compared with four MPPT algorithms, namely the perturb and observe (P&O)-MPPT, incremental conductance (INC)-MPPT, particle swarm optimization (PSO)-MPPT and whale optimization algorithm (WOA)-MPPT. Simulation and experiment results demonstrate that the proposed algorithm can extract the global maximum power point (MPP) with greater tracking speed and accuracy under various conditions.

Inhibition of Transient Receptor Potential Melastain 7 Enhances Apoptosis Induced by TRAIL in PC-3 cells

Lin, Chang-Ming,Ma, Ji-Min,Zhang, Li,Hao, Zong-Yao,Zhou, Jun,Zhou, Zhen-Yu,Shi, Hao-Qiang,Zhang, Yi-Fei,Shao, En-Ming,Liang, Chao-Zhao Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.10

Transient receptor potential melastain 7 (TRPM7) is a bifunctional protein with dual structure of both ion channel and protein kinase, participating in a wide variety of diseases including cancer. Recent researches have reported the mechanism of TRPM7 in human cancers. However, the correlation between TRPM7 and prostate cancer (PCa) has not been well studied. The objective of this study was to investigate the potential the role of TRPM7 in the apoptosis of PC-3 cells, which is the key cell of advanced metastatic PCa. In this study, we demonstrated the influence and potential function of TRPM7 on the PC-3 cells apoptosis induced by TNF-related apoptosis inducing-ligand (TRAIL). The study also found a novel up-regulated expression of TRPM7 in PC-3 cells after treating with TRAIL. Suppression of TRPM7 by TRPM7 non-specific inhibitors ($Gd^{3+}$ or 2-aminoethoxy diphenylborate (2-APB) ) not only markedly eliminated TRPM7 expression level, but also increased the apoptosis of TRAIL-treated PC-3 cells, which may be regulated by the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway accompany with up-regulated expression of cleaved Caspase-3, (TRAIL-receptor 1, death receptors 4) DR4, and (TRAIL-receptor 2, death receptors 5) DR5. Taken together, our findings strongly suggested that TRPM7 was involved in the apoptosis of PC-3 cells induced by TRAIL, indicating that TRPM7 may be applied as a therapeutic target for PCa.

Population genetics reveals new introgression in the nucleus herd of min pigs

Liu Tianxin,Ji Dongqing,Li Xinyuan,Liu Jiadong,Xu Fei,Miao Zhiying,Chang Yang,Tian Ming,Xu Chunzhu 한국유전학회 2024 Genes & Genomics Vol.46 No.4

Objective Min pigs are a unique genetic resource among local pig breeds in China. They have more excellent characteristics in cold and stress resistance, good meat quality, and a high reproductive rate. However, the genetic structure and driving factors remain unclear in the nucleus herd. In this study, the genetic diversity of Min pigs was studied to reveal the formation mechanism of its unique genetic structure. We hope to protect and develop the genetic resources of Min pigs. Methods We analyzed different types of genes to identify the genetic structure and gene introgression pattern of Min pigs. The nuclear DNA dataset includes information on 21 microsatellite loci and 6 Y-chromosome genes, and the mitochondrial D-loop gene is selected to represent maternal lineages. The above genes are all from the nucleus herd of Min pigs. Results The results of genetic structure identification and analysis of potential exogenous gene introgression patterns indicate that the nucleus herd of Min pigs maintains a high level of genetic diversity (polymorphism information content = 0.713, expected heterozygosity = 0.662, observed heterozygosity = 0.612). Compared with other Asian pig breeds, the formation of Min pig breeds is more special. Gene introgression from European pig breeds to Min pigs has occurred, which is characterized by complete introgression of paternal genes and incomplete introgression of maternal genes. Conclusion Gene introgression caused by cross-breeding is not the main factor leading to the formation of the current genetic structure of Min pigs, but this process has increased the level of genetic diversity in the nucleus herd. Compared with the influence of gene introgression, our research suggest that artificial selection and environmental adaptive evolution make Min pigs form unique genetic characteristics. Objective Min pigs are a unique genetic resource among local pig breeds in China. They have more excellent characteristics in cold and stress resistance, good meat quality, and a high reproductive rate. However, the genetic structure and driving factors remain unclear in the nucleus herd. In this study, the genetic diversity of Min pigs was studied to reveal the formation mechanism of its unique genetic structure. We hope to protect and develop the genetic resources of Min pigs. Methods We analyzed different types of genes to identify the genetic structure and gene introgression pattern of Min pigs. The nuclear DNA dataset includes information on 21 microsatellite loci and 6 Y-chromosome genes, and the mitochondrial D-loop gene is selected to represent maternal lineages. The above genes are all from the nucleus herd of Min pigs. Results The results of genetic structure identification and analysis of potential exogenous gene introgression patterns indicate that the nucleus herd of Min pigs maintains a high level of genetic diversity (polymorphism information content = 0.713, expected heterozygosity = 0.662, observed heterozygosity = 0.612). Compared with other Asian pig breeds, the formation of Min pig breeds is more special. Gene introgression from European pig breeds to Min pigs has occurred, which is characterized by complete introgression of paternal genes and incomplete introgression of maternal genes. Conclusion Gene introgression caused by cross-breeding is not the main factor leading to the formation of the current genetic structure of Min pigs, but this process has increased the level of genetic diversity in the nucleus herd. Compared with the influence of gene introgression, our research suggest that artificial selection and environmental adaptive evolution make Min pigs form unique genetic characteristics.

Morphology control of mesoporous Cu₂O by reductants and its photocatalytic activity

Chu, Xiao-Zhong,Cheng, Zhi-Peng,Zhao, Yi-Jiang,Xu, Ji-Ming,Li, Mei-Sheng,Hu, Lei,Zhou, Shou-Yong,Wu, Fei-Yue,Lee, Chang-Ha Elsevier 2017 CERAMICS INTERNATIONAL Vol.43 No.11

<P><B>Abstract</B></P> <P>Mesoporous Cu<SUB>2</SUB>O particles with different morphologies were synthesized via simple one-pot reactions. Effects of reducing agents, dispersant, template, and temperature on the <B>structure</B> of the prepared materials were investigated. Mesoporous flower-shaped Cu<SUB>2</SUB>O materials were obtained at 70℃ using glucose <B>as a reductant</B>. Different hollow microsphere shapes of Cu<SUB>2</SUB>O could be prepared at 40℃ using <B>another type of reductant, ascorbic acid</B>. The results indicated that the uniform morphology of synthesized Cu<SUB>2</SUB>O with mesopores presented a maximum specific surface area of 45.3m<SUP>2</SUP>/g. Furthermore, the as-prepared Cu<SUB>2</SUB>O particles showed good photodegradation efficiencies of methyl orange in the range of 86.0–93.7%, depending on their morphologies.</P>