Distributed Global Velocity-free Attitude Coordination Control for Multiple Spacecraft without Unwinding

Zhihao Zhu,Zhi Gao,Yu Guo 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.2

The distributed global velocity-free attitude coordination control problem for multiple formation spacecraft without unwinding phenomenon and with disturbance is investigated in this paper. Initially, a fixed-time observer is constructed to estimate the states of the virtual leader in fixed time. For the formation spacecraft with attitude-only measurements, a filter system is developed. To estimate the disturbance, a fixed-time extended state observer is proposed. With the application of the fixed-time observers and the filter system, a distributed global velocity-free attitude coordination controller is designed to grantee that the leader with time-varying trajectory can be tracked coordinately by the formation spacecraft, where the unwinding problem of the spacecraft can be avoided. In addition, a distributed velocity-free attitude coordination controller on the basis of the fixed-time extended state observer is designed to compensate the effect of the lump disturbance. Finally, the effectiveness of the proposed controller is demonstrated by numerical simulation.

Low Expression of Circulating MicroRNA-34c is Associated with Poor Prognosis in Triple-Negative Breast Cancer

Zhihao Zeng,Xiaowu Chen,Dajian Zhu,Zhongran Luo,Min Yang 연세대학교의과대학 2017 Yonsei medical journal Vol.58 No.4

Purpose: The microRNA-34 (miR-34) family is important in tumor regulation. This study aimed to investigate the association of circulating miR-34 family proteins with clinicopathological features and their prognostic value in triple-negative breast cancer (TNBC) patients. Materials and Methods: In this cohort study, 173 TNBC patients admitted to First People’s Hospital of Shunde from May 1, 2009 to April 30, 2013 were enrolled. Meanwhile, 75 age-matched healthy women volunteers were identified as healthy controls (HCs). We examined the expression of miR-34 family (miR-34a/b/c) proteins in plasma collected from TNBC patients before any treatmentwas performed and from age-matched HCs using qPCR methods. Results: The expressions of miR-34a/34b/34c were significantly lower in TNBC patients than in HC (p<0.001, p=0.027, p<0.001, respectively). miR-34a was correlated with tumor grade (p=0.038), lymph node positive (p=0.027), distant metastasis (p=0.004), and surgery (p=0.023); miR-34b was correlated with lymph node positivity (p=0.027); and miR-34c was correlated with tumor grade (p=0.017) and distant metastasis (p<0.001). Kaplan-Meier curve analysis displayed low expression of miR-34a as associated with worse overall survival (OS) (p=0.011), as well as miR-34c low expression (p=0.002). In addition, univariate and multivariate Cox proportional hazards regression was performed, and low expression of miR-34c (p=0.011) was found to be an independent risk factor for OS, as well as tumor grade (p=0.013), lymph node positive (p=0.050), and distant metastasis (p=0.021). Conclusion: In conclusion, this study demonstrated reduced miR-34a/c expression is highly associated with tumor progression and indicated worse prognosis. Also, miR-34c was an independent risk factor for OS in TNBC patients.

Ginsenoside Rg3 ameliorates myocardial glucose metabolism and insulin resistance via activating the AMPK signaling pathway

Jingyu Ni,Zhihao Liu,Miaomiao Jiang,Lan Li,Jie Deng,Xiaodan Wang,Jing Su,Yan Zhu,Feng He,Jingyuan Mao,Xiumei Gao,Guanwei Fan 고려인삼학회 2022 Journal of Ginseng Research Vol.46 No.2

Background: Ginsenoside Rg3 is one of the main active ingredients in ginseng. Here, we aimed to confirm its protective effect on the heart function in transverse aortic coarctation (TAC)-induced heart failure mice and explore the potential molecular mechanisms involved. Methods: The effects of ginsenoside Rg3 on heart and mitochondrial function were investigated by treating TAC-induced heart failure in mice. The mechanism of ginsenoside Rg3 for improving heart and mitochondrial function in mice with heart failure was predicted through integrative analysis of the proteome and plasma metabolome. Glucose uptake and myocardial insulin sensitivity were evaluated using micro-positron emission tomography. The effect of ginsenoside Rg3 on myocardial insulin sensitivity was clarified by combining in vivo animal experiments and in vitro cell experiments. Results: Treatment of TAC-induced mouse models with ginsenoside Rg3 significantly improved heart function and protected mitochondrial structure and function. Fusion of metabolomics, proteomics, and targeted metabolomics data showed that Rg3 regulated the glycolysis process, and Rg3 not only regulated glucose uptake but also improve myocardial insulin resistance. The molecular mechanism of ginsenoside Rg3 regulation of glucose metabolism was determined by exploring the interaction pathways of AMPK, insulin resistance, and glucose metabolism. The effect of ginsenoside Rg3 on the promotion of glucose uptake in IR-H9c2 cells by AMPK activation was dependent on the insulin signaling pathway. Conclusions: Ginsenoside Rg3 modulates glucose metabolism and significantly ameliorates insulin resistance through activation of the AMPK pathway.

Model-free predictive current control for IPMSMs with multiple current difference updating technique

Wu, Xiaoxin,Zhu, Zhihao,Liu, Xing,Yu, Feng The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.3

This paper proposes a model-free predictive current control (MFPCC) for interior permanent magnet synchronous motors (IPMSMs) with a multiple current difference updating (MCDU) technique. Firstly, to improve robustness against machine parameter variations and reduce the computational burden, current difference-based prediction that only requires accumulation operation is implemented, which avoids the model-based complex calculations in traditional model predictive current control (MPCC). Secondly, a MCDU technique is conducted with the characteristic of updating the current differences associated with voltage vectors in opposite directions. Thus, the updating frequency of the current difference can be significantly increased. Finally, the effectiveness of the proposed method is verified by simulation and experimental results.

Color stability and degradation kinetics of anthocyanins in mulberry stirred yoghurt fermented by different starter cultures

Xin Cheng,Jinpeng Zhu,Zhijie Chen,Zhihao Wu,Fuqiang Zhang,Cai-e Wu,Gong-Jian Fan 한국식품과학회 2023 Food Science and Biotechnology Vol.32 No.10

To evaluate the storage stability of anthocyanin in stirred yoghurt, mulberry juice and different starter cultures (S) were added into milk to investigate the color stability and degradation kinetics of anthocyanin. The result showed that the redness value decreased, while the brightness value increased, and the anthocyanin content decreased significantly from 1.47 ~ 1.86 to 1.01 ~ 1.19 mg/g. The degradation kinetics followed a first-order reaction. Principal component analysis showed that S2 and S6 were correlated with anthocyanins, S8 and S4 were correlated with a*. At the later stage, S4, S8 were correlated with a*, while S2, S4, S6 were correlated with anthocyanins. At 28th day, the anthocyanin content of S4 was 1.14 mg/g, which was not the highest, but the total score was the highest. Therefore, S4 was the best choice when the storage period is 28 days. This study provided technical support for the selection of a better starter for stirring yoghurt.

Coupled Orbit-attitude Saturated Control for Solar Sail in Earth-Moon 3-body System

Liping Wu,Yu Guo,Zhihao Zhu 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.11

This paper aims to investigate a coupled orbit-attitude control strategy for a kind of novel spacecraft, solar sail, to track the given orbit in Earth-Moon 3-Body dynamic environment in presence of the matched and mismatched disturbances, attitude control saturation, orbital modeling error and parametric uncertainties. A cascaded triple-loop control structure is proposed to deal with the strong couplings between the orbit and attitude systems. The inner loop focusing on the orbital effects on attitude dynamics, an adaptive saturation controller is proposed to achieve attitude angular tracking, where the uncertain inertia, unknown matched disturbance and saturated attitude control torque are compensated by combining the unknown knowledge. The middle loop is to handle the orbit effects on attitude kinematics facing the mismatched disturbance. In the outer loop, the effects of attitude systemon orbit dynamics are deal with, where an adaptive orbit controller is designed considering the uncertain optical parameter and orbital modeling error. The proposed control structure efficiently simplifies the coupled orbit-attitudecontrol design for solar sail. In contrast to traditional coupled controllers for solar sail, the proposed control laws do not require exact knowledge of parametric uncertainties, disturbances and orbit modeling errors. The combination of unknown information reduces the number of estimated parameters as well. The numerical simulation results demonstrate the effectiveness of the proposed control strategy.

Genomic diversity of the Avian leukosis virus subgroup J gp85 gene in different organs of an infected chicken

Fanfeng Meng,Xue Li,Jian Fang,Yalong Gao,Lilong Zhu,Guiju Xing,Fu Tian,Yali Gao,Xuan Dong,Shuang Chang,Peng Zhao,Zhizhong Cui,Zhihao Liu 대한수의학회 2016 Journal of Veterinary Science Vol.17 No.4

The genomic diversity of Avian leukosis virus subgroup J (ALV-J) was investigated in an experimentally infected chicken. ALV-J variantsin tissues from four different organs of the same bird were re-isolated in DF-1 cells, and their gp85 gene was amplified and cloned. Ten clonesfrom each organ were sequenced and compared with the original inoculum strain, NX0101. The minimum homology of each organ rangedfrom 96.7 to 97.6%, and the lowest homology between organs was only 94.9%, which was much lower than the 99.1% homology of inoculumNX0101, indicating high diversity of ALV-J, even within the same bird. The gp85 mutations from the left kidney, which contained tumors,and the right kidney, which was tumor-free, had higher non-synonymous to synonymous mutation ratios than those in the tumor-bearing liverand lungs. Additionally, the mutational sites of gp85 gene in the kidney were similar, and they differed from those in the liver and lung, implyingthat organ- or tissue-specific selective pressure had a greater influence on the evolution of ALV-J diversity. These results suggest that moreALV-J clones from different organs and tissues should be sequenced and compared to better understand viral evolution and molecularepidemiology in the field.

Enhancing Performances of Polyamide 66 Short Fiber/Natural Rubber Composites via In Situ Vulcanization Reaction

Zhi Hao,Junqi Shen,Xiang Sheng,Zong Shen,Le Yang,Xuefeng Lu,Zhu Luo,Qiang Zheng 한국섬유공학회 2020 Fibers and polymers Vol.21 No.2

This paper details a new method for improving the interfacial bonding between PA66 short fiber (PSF) and natural rubber (NR) by reaction of the methacrylic acid (MAA)-grafting-modified PSF with rubber during vulcanization. Carboncarbon double bonds introduced to the SF surface by MAA grafting were opened, and a vulcanization reaction occurred between the modified PSF and rubber in the presence of sulfur. The chemical reactions were verified by FTIR and XPS. The processing rheological behaviors of the compounded composites were investigated by a rubber processing analyzer (RPA). The morphology of modified PSF was characterized by AFM and SEM. The improved interfacial bonding was confirmed by DMA, which enhanced deformational stress at definite elongation of the NR/PSF composites. The volume concentration of the MAA solution for grafting on the SF surface had a great influence on the interfacial bonding and mechanical properties of the composites; when the volume concentration was 30 %, the modified PSF-reinforced NR/CB had the best interfacial bonding and mechanical properties.