Subspace Identification for Fractional Order Hammerstein Systems Based on Instrumental Variables

Zeng Liao,Zhuting Zhu,Shu Liang,Cheng Peng,Yong Wang 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.5

This paper focuses on time-domain identification issues of multi-input multi-output (MIMO) fractional order Hammerstein systems which are the extension of traditional Hammerstein type models by allowing linear part to be fractional order systems. The principal component analysis (PCA) method in subspace family is extended to identify coefficient matrixes of fractional order systems. Singular value decomposition (SVD) is utilized to estimate the unknown parameters of nonlinear part of system directly. A proper instrumental variable is chosen to eliminate the bias of identification results. Numerical simulation validates the proposed method.

8-60hIPP5^m-Induced G2/M Cell Cycle Arrest Involves Activation of ATM/p53/p21^cip1/waf1 Pathways and Delayed Cyclin B1 Nuclear Translocation

Zeng, Qi-Yan,Zeng, Lin-Jie,Huang, Yu,Huang, Yong-Qi,Zhu, Qi-Fang,Liao, Zhi-Hong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.9

Protein phosphatase 1 (PP1) is a major serine/threonine phosphatase that controls gene expression and cell cycle progression. The active mutant IPP5 ($8-60hIPP5^m$), the latest member of the inhibitory molecules for PP1, has been shown to inhibit the growth of human cervix carcinoma cells (HeLa). In order to elucidate the underlying mechanisms, the present study assessed overexpression of $8-60hIPP5^m$ in HeLa cells. Flow cytometric and biochemical analyses showed that overexpression of $8-60hIPP5^m$ induced G2/M-phase arrest, which was accompanied by the upregulation of cyclin B1 and phosphorylation of G2/M-phase proteins ATM, p53, $p21^{cip1/waf1}$ and Cdc2, suggesting that $8-60hIPP5^m$ induces G2/M arrest through activation of the ATM/p53/$p21^{cip1/waf1}$/Cdc2/cyclin B1 pathways. We further showed that overexpression of $8-60hIPP5^m$ led to delayed nuclear translocation of cyclin B1. $8-60hIPP5^m$ also could translocate to the nucleus in G2/M phase and interact with $pp1{\alpha}$ and Cdc2 as demonstrated by co-precipitation assay. Taken together, our data demonstrate a novel role for $8-60hIPP5^m$ in regulation of cell cycle in HeLa cells, possibly contributing to the development of new therapeutic strategies for cervix carcinoma.

Gefitinib Alone or with Concomitant Whole Brain Radiotherapy for Patients with Brain Metastasis from Non-small-cell Lung Cancer: A Retrospective Study

Zeng, Yin-Duo,Zhang, Li,Liao, Hai,Liang, Ying,Xu, Fei,Liu, Jun-Ling,Dinglin, Xiao-Xiao,Chen, Li-Kun Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.3

Background: Gefitinib, a tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR), is used both as a single drug and concurrently with whole brain radiotherapy (WBRT) the standard treatment for brain metastases (BM), and is reported to be effective in a few small studies of patients with BM from non-small-cell lung cancer (NSCLC). However, no study has compared the two treatment modalities. This retrospective analysis was conducted to compare the efficacy of gefitinib alone with gefitinib plus concomitant WBRT in treatment of BM from NSCLC. Methods: We retrospectively reviewed 90 patients with BM from NSCLC who received gefitinib alone (250mg/day, gefitinib group) or with concomitant WBRT (40Gy/20f/4w, gefitinib-WBRT group) between September 2005 and September 2009 at Sun Yat-Sen University Cancer Center. Forty-five patients were in each group. Results: The objective response rate of BM was significantly higher in gefitinib-WBRT group (64.4%) compared with gefitinib group (26.7%, P<0.001). The disease control rate of BM was 71.1% in gefitinib-WBRT group and 42.2% in gefitinib group (P=0.006). The median time to progression of BM was 10.6 months in gefitinib-WBRT group and 6.57 months in gefitinib group (P<0.001). The median overall survival(OS) of gefitinib-WBRT and gefitinib alone group was 23.40 months and 14.83 months, respectively (HR, 0.432, P=0.002). Conclusion: Gefitinib plus concomitant WBRT had higher response rate of BM and significant improvement in OS compared with gefitinib alone in treatment of BM from NSCLC.

Synthesis and application of zirconium phosphate mesoporous coordination polymer for effective removal of Co(II) from aqueous solutions

Zeng Yang,Yuan Guoyuan,Lan Tu,Li Feize,Yang Jijun,Liao Jiali,Yang Yuanyou,Liu Ning 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.11

A kind of zirconium phosphate mesoporous coordination polymer Zr-EDTMPA was successfully synthesized and characterized using XRD, FTIR, TGA, EA, SEMeEDS, and N2 sorption-desorption measurements. The prepared Zr-EDTMPA was first employed for the removal of Co(II) from an aqueous solution, and the effects of pH, contact time, temperature, initial Co(II) concentration, reusability, and sorption mechanism were systematically investigated. The results showed that the Zr-EDTMPA is a zirconium phosphate complex formed by the coordination of EDTMPA to Zr in a molar ratio of 1:1. The sorption of Co(II) by Zr-EDTMPA was a pH-dependent, spontaneous and endothermic process, which was better fitted to the pseudo-second-order kinetic model and Langmuir isotherm model. The Zr-EDTMPA was demonstrated to have excellent reusability and presented a high sorption capacity of 73.0 mgg-1 for Co(II) at pH 8.0. The sorption mechanism was mainly attributed to the strong coordination between cobalt and the untapped hydroxyl functional groups on Zr-EDTMPA, which was confirmed by XPS spectra. Therefore, as a candidate sorbent with high sorption capacity and excellent reusability, ZrEDTMPA has a great potential for the removal of Co(II) from aqueous solutions.

Magnetic Properties and Microstructure of DyAlCu-diffusion Sintered Nd-Fe-B Magnets

Chunfa Liao,Xun Zhou,Peng Jiang,Zhiyong Zeng,Lianghua Que 한국자기학회 2022 Journal of Magnetics Vol.27 No.2

The ability to improve the coercivity of sintered Nd-Fe-B diffused by Dy-Al-Cu alloy derived from electrolysis in a fluoride salt-oxide system was evaluated. The results show that with the increase in heat treatment time, the coercivity of the magnet firstly increased and then decreased. Holding at 900 ℃ for 4 h, tempering at low temperature for 3 h at 550 ℃, the coercivity of GBDPed magnet increased by 44.34 %, the remanence decreased by 1.26 %, the Dy-rich shell phase was recognizable, and the Nd-rich phase evenly distributed. Electron microscope analysis showed that when the GBDP time was longer than 4h, the diffusion of Dy from the shell phase to the matrix phase dominated, decreasing the coercivity with the increase in the diffusion time. The increase of Fe content in the grain boundary phase enhanced the exchange coupling between grains, which also reduced the coercivity of the GBDPed magnet. The infiltration of the matrix phase by excessive Dy and deterioration of (00L) texture of Nd-Fe-B resulted in the reduction of the remanence and the maximum energy product.

Analysis and design of composite‑structure resonant switched‑capacitor voltage equalization topology for series energy storage systems

Wubing Liao,Yuanrui Chen,Jun Zeng,Xiaobin Hong 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.4

Existing voltage equalization topologies based on the switched-capacitor (SC) operate in the hard-switch state with large energy losses and slow balancing speeds. Therefore, a voltage equalization topology derived from a composite-structure resonant switched-capacitor is proposed in this paper. The proposed topology can achieve zero-current operation and modularity, which reduces system loss and cost. Meanwhile, it can provide two equalization paths from one cell to any other cell, which improves its balancing speed. The zero-current operation, equivalent circuit, design guidelines, and modularization designs for the proposed topology are analyzed in detail. An experiment prototype is established. Results obtained with the prototype verify that the proposed equalizer can achieve zero-current switching (ZCS), high balancing efficiency, and decoupling characteristic between the balancing time and the number of storage cells.

Molecular Cloning and Characterization of a Novel Stem-specific Gene from Camptotheca acuminata

Pi, Yan,Liao, Zhihua,Chai, Yourong,Zeng, Hainian,Wang, Peng,Gong, Yifu,Pang, Yongzhen,Sun, Xiaofen,Tang, Kexuan Korean Society for Biochemistry and Molecular Biol 2006 Journal of biochemistry and molecular biology Vol.39 No.1

In higher plants, P450s participate in the biosynthesis of many important secondary metabolites. Here we reported for the first time the isolation of a new cytochrome P450 cDNA that expressed in a stem-specific manner from Camptotheca acuminata (designated as CaSS), a native medicinal plant species in China, using RACE-PCR. The full-length cDNA of CaSS was 1735 bp long containing a 1530 bp open reading frame (ORF) encoding a polypeptide of 509 amino acids. Bioinformatic analysis revealed that CASS contained a heme-binding domain PFGXGRRXCX and showed homology to other plant cytochrome P450 monooxygenases and hydroxylases. Southern blotting analysis revealed that there was only one copy of the CaSS present in the genome of Camptotheca acuminata. Northern blotting analysis revealed that CaSS expressed, in a tissue-specific manner, highly in stem and lowly in root, leaf and flower. Our study suggests that CaSS is likely to be involved in the phenylpropanoid pathway.

Influence of the Electrolytic Dy-Cu alloy on the Coercivity of Sintered Nd-Fe-B Magnet

Chun-fa Liao,Xun Zhou,Peng Jiang,Zhiyong Zeng,Lianghua Que 한국자기학회 2022 Journal of Magnetics Vol.27 No.4

The fluorine salt oxide molten-salt electrolytic Dy-Cu alloy was used as a grain boundary diffusion source instead of the doped Dy-Cu alloy. The microstructure and coercivity of the GBDPed magnets with the different diffusion times were studied. The results show that the coercivity increased with the increase in the GBDP time. The ability of the electrolytic Dy-Cu alloy to improve the coercivity of Nd-Fe-B is more advantageous than that of the doped Dy-Cu alloy. Microstructure analysis shows that the segregation and metal inclusion, a small amount of Dy2O3, and the poor synergy diffusion between Dy and Cu lead to the unsatisfactory performance of the doped Dy-Cu alloy to improve the coercivity. The diffusion rate and depth of the GBD source improved by replacing the doped alloy with an electrolytic alloy.

High Step-up Active-Clamp Converter with an Input Current Doubler and a Symmetrical Switched-Capacitor Circuit

He, Liangzong,Zeng, Tao,Li, Tong,Liao, Yuxian,Zhou, Wei The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.3

A high step-up dc-dc converter is proposed for photovoltaic power systems in this paper. The proposed converter consists of an input current doubler, a symmetrical switched-capacitor doubler and an active-clamp circuit. The input current doubler minimizes the input current ripple. The symmetrical switched-capacitor doubler is composed of two symmetrical quasi-resonant switched-capacitor circuits, which share the leakage inductance of the transformer as a resonant inductor. The rectifier diodes (switched-capacitor circuit) are turned off at the zero current switching (ZCS) condition, so that the reverse-recovery problem of the diodes is removed. In addition, the symmetrical structure results in an output voltage ripple reduction because the voltage ripples of the charge/pump capacitors cancel each other out. Meanwhile, the voltage stress of the rectifier diodes is clamped at half of the output voltage. In addition, the active-clamp circuit clamps the voltage surges of the switches and recycles the energy of the transformer leakage inductance. Furthermore, pulse-width modulation plus phase angle shift (PPAS) is employed to control the output voltage. The operation principle of the converter is analyzed and experimental results obtained from a 400W prototype are presented to validate the performance of the proposed converter.

Clarifying the basic phase structure and magnetic behavior of directly quenched (Ce,La)2Fe14B alloys with various Ce/La ratios

X.F. Liao,L.Z. Zhao,J.S. Zhang,G. Ahmed,A.J. Khan,H.X. Zeng,H.Y. Yu,X.C. Zhong,Z.W. Liu,G.Q. Zhang 한국물리학회 2019 Current Applied Physics Vol.19 No.6

To improve the performance/cost ratio of NdFeB based permanent magnets, Ce or/and La substitutions for Nd have been suggested. To better understand the effects of these substitutions, the fundamental behavior of (Ce,La)-Fe-B alloys has to be clearly understood. Here, we reported a systematic investigation on the phase structure, microstructure, and magnetic properties of melt-spun (Ce,La)2Fe14B alloys. The results confirm that partial substitution of Ce by La can effectively enhance the hard magnetism and thermal stability of (Ce1- xLax)2Fe14B alloys, while over 80% La substitution leads to the decomposition of 2:14:1 phase. The lattice parameters a, c and the Curie temperature Tc of 2:14:1 phase increase linearly with the increasing La content. La substitution can effectively refine the grain, resulting in the enhancement of inter-grain exchange coupling. The (Ce0.7La0.3)2Fe14B alloy with a mean grain size of 25 nm exhibits high remanence, maximum energy product and intrinsic coercivity up to 0.69 T, 6.2 MGOe and 217 kA/m, respectively. The present work provides a good understanding on the melt-spun (Ce,La)-Fe-B system for further developing low cost rare earth permanent magnets.