A Hierarchical Model Predictive Voltage Control for NPC/H-Bridge Converters with a Reduced Computational Burden

Zheng Gong,Peng Dai,Xiaojie Wu,Fujin Deng,Dong Liu,Zhe Chen 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.1

In recent years, voltage source multilevel converters are very popular in medium/high-voltage industrial applications, among which the NPC/H-Bridge converter is a popular solution to the medium/high-voltage drive systems. The conventional finite control set model predictive control (FCS-MPC) strategy is not practical for multilevel converters due to their substantial calculation requirements, especially under high number of voltage levels. To solve this problem, a hierarchical model predictive voltage control (HMPVC) strategy with referring to the implementation of g-h coordinate space vector modulation (SVM) is proposed. By the hierarchical structure of different cost functions, load currents can be controlled well and common mode voltage can be maintained at low values. The proposed strategy could be easily expanded to the systems with high number of voltage levels while the amount of required calculation is significantly reduced and the advantages of the conventional FCS-MPC strategy are reserved. In addition, a HMPVC-based field oriented control scheme is applied to a drive system with the NPC/H-Bridge converter. Both steady-state and transient performances are evaluated by simulations and experiments with a down-scaled NPC/H-Bridge converter prototype under various conditions, which validate the proposed HMPVC strategy.

A Hierarchical Model Predictive Voltage Control for NPC/H-Bridge Converters with a Reduced Computational Burden

Gong, Zheng,Dai, Peng,Wu, Xiaojie,Deng, Fujin,Liu, Dong,Chen, Zhe The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.1

In recent years, voltage source multilevel converters are very popular in medium/high-voltage industrial applications, among which the NPC/H-Bridge converter is a popular solution to the medium/high-voltage drive systems. The conventional finite control set model predictive control (FCS-MPC) strategy is not practical for multilevel converters due to their substantial calculation requirements, especially under high number of voltage levels. To solve this problem, a hierarchical model predictive voltage control (HMPVC) strategy with referring to the implementation of g-h coordinate space vector modulation (SVM) is proposed. By the hierarchical structure of different cost functions, load currents can be controlled well and common mode voltage can be maintained at low values. The proposed strategy could be easily expanded to the systems with high number of voltage levels while the amount of required calculation is significantly reduced and the advantages of the conventional FCS-MPC strategy are reserved. In addition, a HMPVC-based field oriented control scheme is applied to a drive system with the NPC/H-Bridge converter. Both steady-state and transient performances are evaluated by simulations and experiments with a down-scaled NPC/H-Bridge converter prototype under various conditions, which validate the proposed HMPVC strategy.

Prediction of Wind Power by Chaos and BP Artificial Neural Networks Approach Based on Genetic Algorithm

Dai-Zheng Huang,Ren-Xi Gong,Shu Gong 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.1

It is very important to make accurate forecast of wind power because of its indispensable requirement for power system stable operation. The research is to predict wind power by chaos and BP artificial neural networks (CBPANNs) method based on genetic algorithm, and to evaluate feasibility of the method of predicting wind power. A description of the method is performed. Firstly, a calculation of the largest Lyapunov exponent of the time series of wind power and a judgment of whether wind power has chaotic behavior are made. Secondly, phase space of the time series is reconstructed. Finally, the prediction model is constructed based on the best embedding dimension and best delay time to approximate the uncertain function by which the wind power is forecasted. And then an optimization of the weights and thresholds of the model is conducted by genetic algorithm (GA). And a simulation of the method and an evaluation of its effectiveness are performed. The results show that the proposed method has more accuracy than that of BP artificial neural networks (BP-ANNs).

Prediction of Wind Power by Chaos and BP Artificial Neural Networks Approach Based on Genetic Algorithm

Huang, Dai-Zheng,Gong, Ren-Xi,Gong, Shu The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.1

It is very important to make accurate forecast of wind power because of its indispensable requirement for power system stable operation. The research is to predict wind power by chaos and BP artificial neural networks (CBPANNs) method based on genetic algorithm, and to evaluate feasibility of the method of predicting wind power. A description of the method is performed. Firstly, a calculation of the largest Lyapunov exponent of the time series of wind power and a judgment of whether wind power has chaotic behavior are made. Secondly, phase space of the time series is reconstructed. Finally, the prediction model is constructed based on the best embedding dimension and best delay time to approximate the uncertain function by which the wind power is forecasted. And then an optimization of the weights and thresholds of the model is conducted by genetic algorithm (GA). And a simulation of the method and an evaluation of its effectiveness are performed. The results show that the proposed method has more accuracy than that of BP artificial neural networks (BP-ANNs).

Accelerating the Sweep3D for a Graphic Processor Unit

Chun Ye Gong,Jie Liu,Hai Tao Chen,Jing Xie,Zheng Hu Gong 한국정보처리학회 2011 Journal of information processing systems Vol.7 No.1

The Blood Neutrophil-to-lymphocyte Ratio Predicts Survival in Patients with Advanced Hepatocellular Carcinoma Receiving Sorafenib

Zheng, You-Bing,Zhao, Wei,Liu, Bing,Lu, Li-Gong,He, Xu,Huang, Jian-Wen,Li, Yong,Hu, Bao-Shan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

Background and Aim: Increasing evidence correlates the presence of systemic inflammation with poor survival in patients with hepatocellular carcinoma (HCC). The aim of this study was to investigate the prognostic significance of the blood neutrophil-to-lymphocyte ratio (NLR) in patients with advanced HCC who received sorafenib monotherapy. Methods: A total of sixty-five patients with advanced HCC, not eligible for locoregional therapy, treated with sorafenib were enrolled. Potential prognostic factors such as age, gender, tumoral characteristics, performance status and NLR were analyzed. Results: Median OS and TTP for the entire cohort were 10.0 months (95%CI, 7.6-12.3 months) and 4.5 months (95% CI, 4.0-4.9 months). The mean NLR at baseline was 2.89. The median OS of patients with a high NLR (>4) was 6.5 months (95%CI, 5.2-7.7 months) compared with 12.5 months (95%CI, 9.9-15.0) for patients with a normal NLR (${\leq}4$) (P=0.01). Age ${\leq}65$, NLR>4, extrahepatic metastases and vascular invasion were all predictors of poorer overall survival. Multivariate analysis showed that NLR > 4, vascular invasion and extrahepatic metastases were independent predictors of poorer overall survival. The median TTP of patients with a high NLR was 2.5 months (95%CI, 1.4-3.6 months) compared with 4.5 months (95%CI, 3.9-5.1 months) for patients with a normal NLR (P=0.012). Conclusions: High baseline NLR was associated with worse OS and TTP for patients with advanced HCC treated with sorafenib.

An SDN based hopping multicast communication against DoS attack

( Zheng Zhao ),( Fenlin Liu ),( Daofu Gong ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.4

Multicast communication has been widely used in the Internet. However, multicast communication is vulnerable to DoS attack due to static router configuration. In this paper, HMC, a hopping multicast communication method based on SDN, is proposed to tackle this problem. HMC changes the multicast tree periodically and makes it difficult for the attackers to launch an accurate attack. It also decreases the probability of multicast communication being attacked by DoS and in the meanwhile, the QoS constrains are not violated. In this research, the routing problem of HMC is proven to be NP-complete and a heuristic algorithm is proposed to solve it. Experiments show that HMC has the ability to resist DoS attack on multicast route effectively. Theoretically, the multicast compromised probability can drop more than 0.6 when HMC is adopt. In addition, experiments demonstrate that HMC achieves shorter average multicast delay and better robustness compared with traditional method, and more importantly, it better defends DoS attack.

Outcomes Based on Risk Assessment of Anastomotic Leakage after Rectal Cancer Surgery

Gong, Jian-Ping,Yang, Liu,Huang, Xin-En,Sun, Bei-Cheng,Zhou, Jian-Nong,Yu, Dong-Sheng,Zhou, Xin,Li, Dong-Zheng,Guan, Xin,Wang, Dong-Feng Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.2

Purpose: Anastomotic leakage (AL) is associated with high morbidity and mortality, high reoperation rates, and increased hospital length of stay. Here we investigated the risk factors for AL after anterior resection for rectal cancer with a double stapling technique. Patients and Methods: Data for 460 patients who underwent primary anterior resection with a double stapling technique for rectal carcinoma at a single institution from 2003 to 2007 were prospectively collected. All patients experienced a total mesorectal excision (TME) operation. Clinical AL was defined as the presence of leakage signs and confirmed by diagnostic work-up according to ICD-9 codes 997.4, 567.22 (abdominopelvic abscess), and 569.81 (fistula of the intestine). Univariate and logistic regression analyses of 20 variables were undertaken to determine risk factors for AL. Survival was analysed using the Cox regression method. Results: AL was noted in 35 (7.6%) of 460 patients with rectal cancer. :Median age of the patients was 65 (50-74) and 161 (35%) were male. The diagnosis of AL was made between the 6th and 12th postoperative day (POD; mean 8th POD). After univariate and multivariate analysis, age (p=0.004), gender (p=0.007), tumor site (p<0.001), preoperative body mass index (EMI) (p<0.001), the reduction of TSGF on 5th POD less than 10U/ml (p=0.044) and the pH value of pelvic dranage less than or equal to 6.978 on 3rd POD (p<0.001) were selected as 6 independent risk factors for AL. It was shown that significant differences in survival of the patients were AL-related (p<0.001), high ASA score related (p=0.036), high-level EMI related (p=0.007) and advanced TNM stage related <p<0.001). Conclusions: AL after anterior resection for rectal carcinoma is related to advanced age, low tumor site, male sex, high preoperative EMI, low pH value of pelvic drainage on POD 3 and a significant reduction of TSGF on POD 5. In addition to their high risk of immediate postoperative morbidity and mortality, AL, worse physical status, severe obesity and advanced TNM stage have similarly negative impact on survival.

Integrated omics approaches to characterize a nuclear receptor corepressor-associated histone deacetylase in mouse skeletal muscle

Gong, Yingyun,Cao, Rui,Ding, Guolian,Hong, Sungguan,Zhou, Wenjun,Lu, Wenyun,Damle, Manashree,Fang, Bin,Wang, Chuhan C.,Qian, Justin,Lie, Natasha,Lanzillotta, Cristina,Rabinowitz, Joshua D.,Sun, Zheng Elsevier 2018 Molecular and cellular endocrinology Vol.471 No.-

<P><B>Abstract</B></P> <P>Nuclear receptors regulate gene expression by differentially binding to coactivators or corepressors in a ligand-dependent manner, which further recruits a set of epigenome-modifying enzymes that remodel chromatin conformation. Histone acetylation is a major epigenomic change controlled by histone acetyltransferases (HATs) and histone deacetylases (HDACs). HDAC3 is the only HDAC that confers the enzymatic activity to the complexes nucleated by nuclear receptor corepressors NCoR and SMRT. To address the metabolic function of HDAC3, we have deleted it specifically in mouse skeletal muscles. We have performed the following omics profiling in skeletal muscles of these mice: (1) RNA-seq profiling of total RNA; (2) Global nuclear run-on (GRO-seq) analysis of nascent RNAs; (3) Chromatin immuno-precipitation (ChIP-seq) of HDAC3 at both early evening and early morning; (4) proteomics profiling with mass spectrometry; (5) snap-shot metabolomics profiling of water-soluble metabolites at the basal condition; (6) snap-shot metabolomics profiling of lipid species at the basal condition; (7) kinetic fluxomics analysis of glucose utilization using <SUP>13</SUP>C<SUB>6</SUB>-glucose <I>In vivo</I> during treadmill running exercise. These approaches have provided several novel insights into how nuclear receptors regulate circadian rhythm of skeletal muscle fuel metabolism, which has been published elsewhere. Here we present the original datasets and technical details during the execution, analysis, and interpretation of these omics studies.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A mouse model with skeletal muscle-specific KO of HDAC3. </LI> <LI> <I>in vivo</I> RNA-seq, GRO-seq, and ChIP-seq identified relevance to circadian clock. </LI> <LI> Total proteome profiling in muscle samples. </LI> <LI> Metabolomics profiling identified disruption of BCAAs metabolism. </LI> <LI> Fluxomics with <SUP>13</SUP>C-glucose <I>in vivo</I> during treadmill running. </LI> </UL> </P>

Anti-Oxidation of Cultured Cordyceps militaris Growing on Silkworm Pupa

Gong Cheng-Liang,Pan Zhong-Hua,Zheng Xiao-Jian,Xue Ren-Yu,Cao Guang Li Korean Society of Sericultural Science 2006 International Journal of Industrial Entomology Vol.12 No.1

Cordyceps, one of the well-known traditional Chinese medicines, consists of the dried fungus C. sinensis growing on the larva of caterpillar. It is commonly used as a tonic of restoring vital body functions. In order to evaluate the pharmacological effects of C. militaris, the anti-oxidation and antiaging effect of cultured C. militaris growing on pupa of silkworm Bombyx mori, were investigated. The results showed! that the contents of lipofusin in myocardium were reduced and the SOD activity in the liver were elevated in a dose-dependent manner while no effect was observed for blood GSH-Px activity and liver MDA content in mice perfused with the cultured C. militaris compared to those untreated mice. Furthermore, the average life span, maximum life span and 50% death time of the fruit flies treated with cultured C. militaris were markedly prolonged. The results suggest that the cultured C. militaris growing on pupa of silkworm possesses anti-oxidation and delay senescence activity.