Fault Tolerant H∞ Control for a Class of Polynomial Non-linear Discrete-time Systems

Xian-Ji Meng,Guang-Hong Yang 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.4

This paper studies the fault tolerant control (FTC) problem for a class of polynomial nonlinear discrete-time systems with guaranteed H∞ performance in the presence of actuator faults. The con-cerned fault is considered as a multi-model of the typical aberration in actuators’ effectiveness. A quadratic-like polynomial Lyapunov function is presented for the H∞ specification. The main contribution of this paper is that the effect of the nonlinear terms appear in FTC analysis is described as an index in order to transform the controller design into a semi-definite programming (SDP). A numerical example is given to verify the applicability of this new approach for the nonlinear FTC synthesis.

Involvement of Nuclear Factor Kappa B in High-Fat Diet-Related Pancreatic Fibrosis in Rats

( Ming Xian Yan ),( Hong Bo Ren ),( Yi Kou ),( Min Meng ),( Yan Qing Li ) 대한소화기학회 2012 Gut and Liver Vol.6 No.3

Background/Aims: High-fat diets contribute to pancreatic fibrogenesis, but the pathogenesis remains unclear. This study investigated the role of nuclear factor kappa B (NF-κB) in high-fat diet-induced pancreatic fi brosis in rats. Methods: Male Wistar rats were fed a high-fat diet or standard normal chow for 20 weeks. Pancreatic fibrosis was determined by Sirius red staining. Immunohistochemical staining, reverse transcription-polymerase chain reaction and Western blotting were used to identify NF-κB-associated genes or protein expressions. Results: Infl ammation, fat deposition, pancreatic stellate cell activation and fi brosis were observed in the pancreases of the high-fat diet group. NF-κB subunit p65 (NF-κB/ p65) expression was localized to the nucleus, and intercellular adhesion molecule 1 (ICAM-1) was over-expressed. Pancreatic gene expression levels of NF-κB/p65, ICAM-1 and tumor necrosis factor α were all elevated signifi cantly in rats fed a high-fat diet compared with control rats. Western blotting also revealed signifi cantly increased levels of ICAM-1 and nuclear NF-κB/p65 in rats fed high-fat diets comparison with control rats. Conclusions: NF-κB is involved in high-fat diet-related pancreatic fi brosis. (Gut Liver 2012;6:381-387)

Practical Calculation Method for the Short‑Circuit Current of Power Grids with High Temperature Superconducting Fault Current Limiters

Hai‑feng Hong,Meng‑ze Yu,Xiao‑hui Zhang,Jia‑jia Huan,Yu Sui,Xian‑xian Pan 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.2

With the expansion of the power grid scale and the enhancement of network structure interconnection, the short-circuit current of power grids is increasingly close to the upper capacity limit of circuit breakers. The fault current limiter is efective in suppressing the short-circuit current of power grids, and with the mature development of superconducting technology, high-temperature superconducting fault current limiters (HTS-FCLs) have been widely used in power grids. Due to the nonlinear impedance–current characteristic of HTS-FCLs, the traditional short-circuit current calculation method is inapplicable to power grids with HTS-FCLs. First, based on the establishment of the electromechanical transient model and the short-circuit calculation model, the short-circuit current calculation procedure for power grids with HTS-FCLs is proposed. Second, the calculation methods for three-phase and single-phase short-circuit currents at the substation bus in power grids with HTS-FCLs are analyzed. Finally, three-phase and single-phase short-circuit currents at the 500 kV Xijiang substation bus in the Guangdong power grid are calculated as the study case. Simulation results show that compared with the situation where there is no HTS-FCL installed, the short-circuit current on the 500 kV bus decreases from 65.34 to 58.31 kA in terms of the three-phase short-circuit fault, and decreases from 54.56 to 46.62 kA in terms of the single-phase short-circuit fault, thus verifying the efectiveness and practicability of HTS-FCLs in suppressing the short-circuit current, which is signifcant for the safe, stable and reliable operation of the power grid.

Multi-stage Nonlinear Model Predictive Control with Online Scenario Update for Semi-batch Polymerization Processes

Jing-Gao Sun,Xian-Feng Chen,Guang-Hao Su,Meng Wang,Hong-Guang Pan 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.10

In this paper, the problem of multi-stage nonlinear model predictive control with scenario update is investigated for semi-batch polymerization processes. The objective is to propose novel online scenario update schemes such that the more reasonable scenario tree can be generated. Firstly, based on the Orthogonal Configuration of Finite Elements (OCFE) method of direct radau configuration, the dynamic optimization problems are converted to Nonlinear Programing (NLP) problems such that the speed and accuracy of real-time optimization problem solving are effectively improved. Then, the scenario deviation is calculated based on model prediction information of each scenario and process measurement information. After that, calculate the bayesian probability weight of corresponding scenario is obtained. The online scenario reduction scheme uses the weight information update scenarios gradually reduce the scope of scenario tree representation. The online scenario weight update scheme uses the weight information as the basis for weight assignment of each scenario in the optimization problem. They use different methods to make the scenario tree modeling approach the real realization of uncertainty, and reduce the conservativeness compared with the traditional MSNMPC fixed scenario tree method. Through multiple batches numerical simulations of a semi-batch polymerization process, the advantages and effectiveness of the two proposed schemes are verified.

Anti-tumor Efficacy of a Hepatocellular Carcinoma Vaccine Based on Dendritic Cells Combined with Tumor-derived Autophagosomes in Murine Models

Su, Shu,Zhou, Hao,Xue, Meng,Liu, Jing-Yu,Ding, Lei,Cao, Meng,Zhou, Zhen-Xian,Hu, Hong-Min,Wang, Li-Xin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.5

The majority of hepatocellular carcinoma (HCC) patients have a poor prognosis with current therapies, and new approaches are urgently needed. We have developed a novel therapeutic cancer vaccine platform based on tumor cell derived autophagosomes (DRibbles) for cancer immunotherapy. We here evaluated the effectiveness of DRibbles-pulsed dendritic cell (DC) immunization to induce anti-tumor immunity in BALB/c mouse HCC and humanized HCC mouse models generated by transplantation of human HCC cells (HepG2) into BALB/c-nu mice. DRibbles were enriched from H22 or BNL cells, BALB/c-derived HCC cell lines, by inducing autophagy and blocking protein degradation. DRibbles-pulsed DC immunization induced a specific T cell response against HCC and resulted in significant inhibition of tumor growth compared to mice treated with DCs alone. Antitumor efficacy of the DCs-DRibbles vaccine was also demonstrated in a humanized HCC mouse model. The results indicated that HCC/DRibbles-pulsed DCs immunotherapy might be useful for suppressing the growth of residual tumors after primary therapy of human HCC.

PDCD4 as a Predictor of Sensitivity to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer Patients

Dou, Xue,Wang, Ren-Ben,Meng, Xiang-Jiao,Yan, Hong-Jiang,Jiang, Shu-Mei,Zhu, Kun-Li,Xu, Xiao-Qing,Chen, Dong,Song, Xian-Rang,Mu, Dian-Bin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.2

Objective: The purpose of this study was to examine the role of programmed cell death 4 (PDCD4) expression in predicting tumor response to neoadjuvant chemoradiotherapy and outcomes for patients with locally advanced rectal cancer. Methods: Clinicopathological factors and expression of PDCD4 were evaluated in 92 patients with LARC treated with nCRT. After the completion of therapy, 4 cases achieved clinical complete response (cCR), and thus the remaining 88 patients underwent a standardized total mesorectal excision procedure. There were 38 patients (41.3%) with a good response (TRG 3-4) and 54 (58.7%) with a poor one (TRG 0-2). Results: Immunohistochemical staining analyses showed that patients with high expression of PDCD4 were more sensitive to nCRT than those with low PDCD4 expression (P=0.02). High PDCD4 expression before nCRT and good response (TRG3-4) were significantly associated with improved 5-year disease-free survival and 5-year overall survival (P<0.05). Multivariate analysis demonstrated that the pretreatment PDCD4 expression was an independent prognostic factor. Conclusion: Our study demonstrated that high expression of PDCD4 protein is a useful predictive factor for good tumor response to nCRT and good outcomes in patients with LARC.

Methylenetetrahydrofolate Reductase Polymorphisms and Susceptibility to Esophageal Cancer in Chinese Populations: a Meta-analysis

Yang, Yong-Bin,Shang, Yan-Hong,Tan, Yan-Li,Kang, Xian-Jiang,Meng, Ming,Zhao, Zhan-Xue Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.3

Although many epidemiologic studies investigated the methylenetetrahydrofolate reductase (MTHFR) polymorphisms and their associations with esophageal cancer, definite conclusions could not be drawn. To clarify the effects of MTHFR polymorphisms on the risk of esophageal cancer, a meta-analysis was here performed in Chinese populations. A total of 16 studies including 3,040 cases and 4,127 controls were involved in this metaanalysis. Overall, significant associations were found between the MTHFR C677T polymorphism and esophageal cancer risk when all studies in Chinese populations were pooled into the meta-analysis (T vs. C, OR = 1.19, 95% CI = 1.06-1.34; TT vs. CC, OR = 1.35, 95% CI = 1.07-1.70; TT+ CT vs. CC, OR = 1.29, 95% CI = 1.08-1.54; TT vs. CC + CT, OR = 1.19, 95% CI = 1.03-1.37). In subgroup analyses stratified by ethnicity and source of controls, the same results were found in Kazakh (TT vs. CC, OR = 1.38, 95% CI = 1.02-1.87; TT + CT vs. CC, OR = 1.50, 95% CI = 1.03-2.18), in not stated populations (T vs. C, OR = 1.24, 95% CI = 1.08-1.42; TT vs. CC, OR = 1.47, 95% CI = 1.10-1.96; TT + CT vs. CC, OR = 1.30, 95% CI = 1.05-1.60; TT vs. CC + CT, OR = 1.32, 95% CI = 1.12-1.56), and in hospital-based studies (T vs. C, OR = 1.34, 95% CI = 1.19-1.51; TT vs. CC, OR = 1.81, 95% CI = 1.37-2.39; TT + CT vs. CC, OR = 1.51, 95% CI = 1.26-1.83; and TT vs. CC + CT, OR = 1.39, 95% CI = 1.13-1.70). In conclusion, this meta-analysis provides evidence that the MTHFR C677T polymorphism contributes to esophageal cancer development in Chinese populations.

A TaqMan Real-Time PCR Assay for Quantifying Type 3 Hepatopancreatic Parvovirus Infections in Wild Broodstocks and Hatchery-Reared Postlarvae of Fenneropenaeus chinensis in Korea

( In Kwon Jang ),( Kannan Suriakala ),( Jong Sheek Kim ),( Xian Hong Meng ),( Tae Jin Choi ) 한국미생물 · 생명공학회 2011 Journal of microbiology and biotechnology Vol.21 No.11

A highly sensitive and specific TaqMan real-time PCR was used to quantify hepatopancreatic parvovirus (HPV) type III infections in wild broodstocks and hatcheryreared postlarvae (PL) of Fenneropenaeus chinensis. Totals of 159 and 162 wild brooders from three locations were captured, and 140 and 180 PL were obtained from seven and six commercial hatcheries in 2007 and 2008, respectively. Among the three wild broodstock groups from 2007, only 1 group showed HPV infection and 3.2% of 159 brooders were positive for HPV infection. In 2008, HPV infections were observed from all three wild broodstock groups with 1.93×10(4) copies/mg tissue of pleopods. Of 162 brooders, 26.6% were positive for HPV infection. No PL from the two hatcheries collected in 2007 showed HPV infection, and PL from the rest of the five hatcheries had up to 1.74×10(6) copies/ng of DNA, and PL from three hatcheries showed HPV infections with over 1,000 copies/ng of DNA. The PL from all seven hatcheries collected in 2008 showed up to 2.10×10(5) HPV copies/ng of DNA. PL from two hatcheries showed less than 100 copies/ng of DNA, but PL from the rest of the hatcheries showed HPV infections with over 1,000 copies/ng of DNA. These results show that HPV type III is widely distributed in Korea in addition to previously reported HPV type I, and they can be effectively detected by type-specific real-time PCR.

Comparison of white spot syndrome virus quantification of fleshy shrimp <i>Fenneropenaeus chinensis</i> in outdoor ponds between different growing seasons by TaqMan real‐time polymerase chain reaction

Jang, In Kwon,Kim, Jong‐,Sheek,Kim, Bong‐,Rae,Meng, Xian‐,Hong Blackwell Publishing Ltd 2011 Aquaculture research Vol.42 No.12

<P><B>Abstract</B></P><P>In the present study, we used TaqMan real‐time polymerase chain reaction to quantify and compare infection of white spot syndrome virus (WSSV) with shrimp production of <I>Fenneropenaeus chinensis</I> cultured in outdoor ponds along the west coast of the South Korea. In 2007, a total of 60 specimens in summer and 116 specimens in autumn were collected from 12 growing‐out ponds and 12 harvest ponds respectively. Pond harvest data were obtained from farmers. Of the summer samples, all specimens were WSSV positive, with a wide range of 12.4–7.0 × 10<SUP>7</SUP> (mean 7.5 × 10<SUP>6</SUP>) copies ng<SUP>−1</SUP> DNA; shrimp production was 1.7 metric tonnes per hectare (mt ha<SUP>−1</SUP>). Of the 116 autumn‐sample specimens, 81 (69.8%) were WSSV positive; WSSV infection had been decreased dramatically, to 0–7.2 (mean 3.5) copies ng<SUP>−1</SUP> DNA. Shrimp production of autumn ponds was 2.1 mt ha<SUP>−1</SUP>. Statistical analysis indicated that the difference in WSSV infections detected in summer and autumn was highly significant (<I>P</I><0.01). In summer, seven ponds (58.3%) with low‐WSSV infection loads (0–1000 WSSV copies ng<SUP>−1</SUP> DNA) had shrimp production of 2.7 mt ha<SUP>−1</SUP>; the others had shrimp production of only 0.2 mt ha<SUP>−1</SUP>. The mean shrimp production between the two infection levels showed a highly statistically significant difference (<I>P</I><0.01).</P>

Real-time PCR Quantification of White Spot Syndrome Virus (WSSV) and Hepatopancreatic Parvovirus (HPV) Loads in Shrimp and Seawaters of Shrimp Ponds on the West Coast of South Korea

장인권,Ayyaru Gopalakannan,Kannan Suriakala,김종식,김봉래,조영록,Xian-Hong Meng,서형철 한국수산과학회 2008 Fisheries and Aquatic Sciences Vol.11 No.4

Viral diseases are major emerging problems of shrimp that have affected the production, and even complete losses for shrimp farms. In this study, we developed a sensitive TaqMan real-time PCR method to quantify white spot syndrome virus (WSSV) and hepatopancreatic parvovirus (HPV) in the shrimp and pond water in which fleshy shrimp, Fenneropenaeus chinensis, and Pacific white shrimp, Litopenaeus vannamei, are reared. WSSV and HPV in pond seawaters ranged from 1.65×103 to 2.43×109 and from 0 to 4.43×105 copies/L of seawater, respectively. Of 20 ponds analyzed, all pond water and shrimp were positive for WSSV. L. vannamei showed higher susceptibility to WSSV than F. chinensis. HPV was detected only in the pond water for F. chinensis. In shrimp tissue, however, HPV was found in both species, with 23-times higher infection rate in F. chinensis than L. vannamei. The total bacterial counts in the pond water ranged from 2.23×103 to 1.98×105 CFU/mL. The variations in total bacterial count for each pond appeared to correlate to the variations of the WSSV load. Statistical analysis indicated that there was no significant difference (P>0.05) between the WSSV load in pond water and shrimp, and there was no relationship between total bacterial load and viral load in the pond water. However, a significant difference (P<0.01) was found between HPV load and L. vannamei and F. chinensis pond water.