Novel Predictive Current Control Pulse Width Modulation Method for Matrix Converters

Yulong Li(리위룽),Nam-Sup Choi(최남섭),Byung-Moon Han(한병문),Seung-Chul Yang(양승철) 대한전기학회 2008 대한전기학회 학술대회 논문집 Vol.2008 No.11

A new pulse width modulation method based on predictive current control strategy is proposed to modulate matrix converters. The predictive current controller utilizes a discrete-time model to predict the future values of output currents and generates proper duty-ratios to minimize the output current errors. The proposed method uses continuous carrier and establishes a predictive current controller to predetermine duty ratio signal for directly generating gating signals an thus is named "predictive current control PWM(PCCPWM)". The modulation algorithm and the required equations are derived by using average concept over one switching period. Thus it can be easily extended to other matrix converter topologies, especially with neutral connections, such as sing le-phase and two-phase matrix converters. The feasibility and validity of the proposed strategy are verified by computer simulation and experimental results.

Robust Adaptive Dynamic Surface Control Based on Structural Reliability for a Turret-moored Floating Production Storage and Offloading Vessel

Yulong Tuo,Yuanhui Wang,Simon X. Yang,Mohammad Biglarbegian,Mingyu Fu 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.4

For floating production storage and offloading (FPSO) vessels, a dynamic positioning controller is necessary because using only a mooring system is not possible to keep the ship within a predefined region. Position control of the FPSO vessel is extremely challenging due to model uncertainties and unknown control coefficients. This paper develops a new robust adaptive positioning controller consisting of several components: adaptive law, dynamic surface control (DSC) technology, sigmoid tracking differentiator (STD), Nussbaum gain function, and structural reliability index. Model uncertainties can be estimated by the adaptive law derived from the Lyapunov theory. The DSC technology is used to eliminate repeated differentiation by introducing first-order filtering of the virtual control. The chattering-free STD with the characteristics of global fast convergence can estimate the derivatives of model uncertainties that are difficult to calculate directly. Therefore, the DSC and STD techniques make the proposed controller simpler to compute and easier to implement in engineering practice. Most of the traditional controllers require the information about the control coefficients to guarantee the stability of the closed-loop system while the Nussbaum gain function can remove the requirement for a priori knowledge of the sign of control coefficients. The capacity of the mooring system can be fully utilized to position the FPSO vessel by adjusting the structural reliability index on the premise of ensuring the safety of mooring lines, and hence less control effort is needed for the positioning controller. Simulations using two sets of system parameters demonstrate the proposed controller’s effectiveness. In addition, a qualitative comparison with the adaptive backstepping controller shows that our proposed controller is computationally more efficient and does not require a priori knowledge of the sign of control coefficients. A quantitative comparison with robust adaptive controller without the structural reliability shows that less control effort is needed using our proposed controller.

Interactive and Worst-Case Optimized Robust Control for Potential Application to Guaranteeing Roll Stability for Intelligent Heavy Vehicle

Liu Yulong,Ji Xuewu,Yang Kai-ming,He Xiangkun,Nakano Shirou 한국자동차공학회 2021 International journal of automotive technology Vol.22 No.5

Roll stability loss of heavy vehicle is a severe road safety problem and modern intelligent heavy vehicle (IHV) raises new requirement for advanced roll stability control technology. Two novel roll stability control frameworks, namely active steering-active anti-roll (AS-AAR) interactive control and worst-case optimized robust control, which have potential application to guaranteeing roll stability of IHV are proposed and investigated in this paper. The first control framework is implemented based on Nash dynamic game theory in which AS-AAR shared control is investigated as a dynamic difference game so that its two players, namely AS and AAR system, can interact with each other to provide satisfactory control performance. This interactive control scheme can be applied to vehicle automated driving scenario to improve vehicle tracking performance and roll stability. Based on zero-sum game theory, the second worst-case optimized robust control scheme is also developed to guarantee vehicle roll stability. This control method provides a suitable design framework to guarantee roll stability in scenario of vehicle-to-driver handover for IHV in which the steering input from human driver is regarded as uncertain disturbance. Simulation results show that both control frameworks can effectively improve roll stability as well as lateral stability while ensuing satisfied tracking performance.

Hair Growth Promoting Effects of 650 nm Red Light Stimulation on Human Hair Follicles and Study of Its Mechanisms via RNA Sequencing Transcriptome Analysis

( Kai Yang ),( Yulong Tang ),( Yanyun Ma ),( Qingmei Liu ),( Yan Huang ),( Yuting Zhang ),( Xiangguang Shi ),( Li Zhang ),( Yue Zhang ),( Ji’an Wang ),( Yifei Zhu ),( Wei Liu ),( Yimei Tan ),( Jinran 대한피부과학회 2021 Annals of Dermatology Vol.33 No.6

Background: Androgenetic alopecia (AGA) leads to thinning of scalp hair and affects 60%~70% of the adult population worldwide. Developing more effective treatments and studying its mechanism are of great significance. Previous clinical studies have revealed that hair growth is stimulated by 650-nm red light. Objective: This study aimed to explore the effect and mechanism of 650-nm red light on the treatment of AGA by using ex vivo hair follicle culture. Methods: Human hair follicles were obtained from hair transplant patients with AGA. Hair follicles were cultured in Williams E medium and treated with or without 650-nm red light. Real-time RT-PCR and immunofluorescence staining were used to detect the expression level of genes and proteins in hair follicles, respectively. RNA-sequencing analysis was carried out to reveal the distinct gene signatures upon 650 nm treatment. Results: Low-level 650 nm red light promoted the proliferation of human hair follicles in the experimental cultured-tissue model. Consistently, 650 nm red light significantly delayed the transition of hair cycle from anagen to catagen in vitro. RNA-seq analysis and gene clustering for the differentially expressed genes suggests that leukocyte transendothelial migration, metabolism, adherens junction and other biological process maybe involved in stimulation of hair follicles by 650-nm red light treatment. Conclusion: The effect of 650-nm red light on ex vivo hair follicles and the transcriptome set which implicates the role of red light in promoting hair growth and reversing of miniaturization process of AGA were identified.

Genome-wide identification and comparative analysis of the TUBBY-like protein gene family in maize

Ma Qing,Chen Yulong,Dai Wei,Sun Baoming,Zhao Yang 한국유전학회 2016 Genes & Genomics Vol.38 No.1

The evolutionary history of TUBBY-like proteins (TLPs), which contain a highly conserved tubby domain, can be traced to the early stages of eukaryote evolution, on account of the identification of this gene family in organisms from single-celled to multicellular eukaryotes. While genome-wide structural and evolutionary analyses of the entire TLP gene family have recently been reported in Arabidopsis and rice, little is known about TLP genes in maize. To gain insight into how TLP genes have evolved in maize, we conducted comprehensive analysis of the molecular evolution of TLP genes in this crop. A total of 15 TLP genes (ZmTLP1–15) were identified in maize by genome-wide screening. This family was classified into four subfamilies based on phylogenetic relationships, protein domains, and motif organization. Gene duplication and chromosomal location analysis indicated that segmental duplication has played a major role in the expansion of the maize TLP family. The ZmTLP genes exhibited differential expression profiles under ABA, NaCl, 42, 4 C, and PEG stress treatment. We performed microsynteny analysis across three gramineous species based on comparisons of the specific regions containing TLP genes, revealing numerous microsyntenic gene pairs among maize, rice, and sorghum, which suggests that the flanking regions of TLP genes may be derived from a common ancient Gramineae ancestor.

Preparation of solid acid catalyst packing AAO/SBA-15-SO3H and application for dehydration of xylose to furfural

Derun Hua,Mingde Yang,Yulong Wu,PanPan Li,Yu Chen,Jie Dang,Quanhua Xie,Ji Liu,Xiao-yin Sun 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.4

The solid acid catalyst packing AAO/SBA-15-SO3H was prepared by the co-condensation and grafting method with porous anodic aluminum oxide (AAO) as support. FT-IR, SEM and TEM were applied to characterize the prepared samples. Results showed that catalysts prepared by two methods both contained active centers, and SBA-15 nanorod arrays grow inside a porous alumina membrane AAO and are perpendicular to the substrate. Their catalytic performances were tested for dehydration of xylose to furfural. The conversion of xylose and selectivity of furfural were 90% and 74% on the AAO/SBA-15-SO3H(C) catalyst prepared by the co-condensation method, respectively. The deactivation and regeneration of the AAO/SBA-15-SO3H(C) catalyst for the dehydration of xylose were also investigated,the activity of catalyst treated by 30 wt.% H2O2 almost was recovered.

A 5.6 kW 11.7 kW per kg Four-Phase Interleaved Buck Converter for the Unmanned Aerial Vehicle

Cheng Xu-Feng,Peng Zhenzhen,Yang Yulong,Liang Zhimin,Wu Chaofeng,Shao Zhiwei,Wang Dianlong 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.2

This paper proposed a 5.6 kW 11.7 kW/kg four-phase interleaved buck converter (FPIBC) for the unmanned aerial vehicle (UAV) low-voltage power system. The UAV mainly concerns the lightweight strategy and the power density of the DC-DC converter. We proposed a comprehensive lightweight strategy with the characteristics of reduced inductor current ripples, small size of fi lter inductors and capacitors, and high output power. The output current ripples are reduced by using interleaved modulation strategy and integrated CLC fi lters cascaded to the input side and output side respectively. In addition, the aluminum based printed circuit board (PCB) is used with SMD power transistors to obtain better heat dissipation capability without fans. With abovementioned methods, the designed DC-DC converter has a power of 5.6 kW @ 0.48 kg, the powerto-weight ratio is improved to be 11.7 kW/kg, and the power density is 3 W/cm 3 . The effi ciency of this DC-DC converter is up to 95.8%.

Dehydration reaction of bio-ethanol to ethylene over modified SAPO catalysts

Yu Chen,Ling Tao,Bin Dai,Mingde Yang,Zhen Chen,Xiaoyan Zhu,Yulong Wu 한국공업화학회 2010 Journal of Industrial and Engineering Chemistry Vol.16 No.5

Mnmodified SAPO-11 (Mn-SAPO-11), Zn-SAPO-11, Mn-SAPO-34 and Zn-SAPO-34 were first synthesized with hydrothermal method in the laboratory. Dehydration of ethanol to ethylene over SAPO-11, SAPO-34and four materials above as catalysts was carried out and Mn-SAPO-34 exhibited the best conversion and selectivity (99.35% and 98.44%, respectively) at 340 8C. The introduction of Mn2+ or Zn2+ into the SAPO channel generated in Mn-SAPO or Zn-SAPO samples was proved by X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption. NH3-TPD study revealed that modification of Mn2+or Zn2+ in the SAPO framework led to increase the weak acid strength and give rise to weak acid sites. The effects of operation parameters, such as loading amount, modification methods, reaction time, reaction temperature, mass space velocity and concentration of ethanol have also been investigated experimentally. 2010 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Chlorogenic Acid Decreased Intestinal Permeability and Ameliorated Intestinal Injury in Rats via Amelioration of Mitochondrial Respiratory Chain Dysfunction

Yan Zhou,Zheng Ruan,Lili Zhou,Yuhui Yang,Shumei Mi,Ze-Yuan Deng,Yulong Yin 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.1

Chlorogenic acid (CGA), an abundant polyphenol compound in plants, exhibits anti-oxidant effects. The protective effect of CGA in the rat intestine with endotoxin infusion was evaluated. CGA administration ameliorated endotoxin-induced intestinal injury, and decreased the ratio of lactulose/ mannitol, the ileum pathological grade, the myeloperoxidase activity in the ileum, and the malondialdehyde content in the ileum and in ileum mitochondria. The small intestine weight, activities of alkaline phosphatase and superoxide dismutase in the ileum, and β-nicotinamide adenine dinucleotide reduce form (NADH) dehydrogenase and succinate dehydrogenase activities in ileum mitochondria were increased. Intestinal permeability was positively correlated with intestinal mitochondrial injury indicated as the level of malondialdehyde in ileum mitochondria, and negatively correlated with NADH dehydrogenase activity. Dietary administration of CGA protected against increased intestinal permeability caused by endotoxin infusion. The protective effect of CGA was probably associated with a decrease in mitochondrial lipid peroxidation levels and an increase in NADH dehydrogenase activity.

Expression profiles of microRNAs in skeletal muscle of sheep by deep sequencing

Zhi-Jin Liu,Cun-Yuan Li,Xiao-Yue Li,Yang Yao,Wei Ni,Xiang-Yu Zhang,Yang Cao,Wureli Hazi,Dawei Wang,Renzhe Quan,Shuting Yu,Yuyu Wu,Songmin Niu,Yulong Cui,Yaseen Khan,Shengwei Hu 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.6

Objective: MicroRNAs are a class of endogenous small regulatory RNAs that regulate cell proliferation, differentiation and apoptosis. Recent studies on miRNAs are mainly focused on mice, human and pig. However, the studies on miRNAs in skeletal muscle of sheep are not comprehensive. Methods: RNA-seq technology was used to perform genomic analysis of miRNAs in prenatal and postnatal skeletal muscle of sheep. Targeted genes were predicted using miRanda software and miRNA-mRNA interactions were verified by quantitative real-time polymerase chain reaction. To further investigate the function of miRNAs, candidate targeted genes were enriched for analysis using gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment. Results: The results showed total of 1,086 known miRNAs and 40 new candidate miRNAs were detected in prenatal and postnatal skeletal muscle of sheep. In addition, 345 miRNAs (151 up-regulated, 94 down-regulated) were differentially expressed. Moreover, miRanda software was performed to predict targeted genes of miRNAs, resulting in a total of 2,833 predicted targets, especially miR-381 which targeted multiple muscle-related mRNAs. Furthermore, GO and KEGG pathway analysis confirmed that targeted genes of miRNAs were involved in development of skeletal muscles. Conclusion: This study supplements the miRNA database of sheep, which provides valuable information for further study of the biological function of miRNAs in sheep skeletal muscle.