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      • KCI등재

        Adaptive ILC for Tracking Non-repetitive Reference Trajectory of 2-D FMM under Random Boundary Condition

        Qing-Yuan Xu,Xiao-Dong Li,Mang-Mang Lv 제어·로봇·시스템학회 2016 International Journal of Control, Automation, and Vol.14 No.2

        Almost all of the existing research achievements in Iterative Learning Control (ILC) hitherto have beenfocused on One-Dimensional (1-D) dynamical systems. Few ILC researches are related to Two-Dimensional FornasiniMarchesina Model (2-D FMM). In this paper, an adaptive ILC approach is proposed for 2-D FMM systemwith non-repetitive reference trajectory under random boundary condition. The proposed adaptive ILC algorithmlearns the coefficient matrices of the system and updates the control input iteratively. As the times of iteration goesto infinity, the ILC tracking error outside the boundary tends to zero and all system signals keep bounded in thewhole ILC process. Illustrative examples are provided to verify the validity of the proposed adaptive ILC algorithm.

      • KCI등재

        Rotor Initial Position Estimation Based on sDFT for Electrically Excited Synchronous Motors

        Qing-qing Yuan,Xiao-jie Wu,Peng Dai 전력전자학회 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.3

        Rotor initial position is an important factor affecting the control performance of electrically excited synchronous motors. This study presents a novel method for estimating rotor initial position based on sliding discrete Fourier transform (sDFT). By injecting an ac excitation into the rotor winding, an induced voltage is generated in stator windings. Through this voltage, the stator flux can be obtained using a pure integral voltage model. Considering the influence from a dc bias and an integral initial value, we adopt the sDFT to extract the fundamental flux component. A quadrant identification model is designed to realize the accurate estimation of the rotor initial position. The sDFT and high-pass filter, DFT, are compared in detail, and the contrast between dc excitation and ac injection is determined. Simulation and experimental results verify that this type of novel method can eliminate the influence of dc bias and other adverse factors, as well as provide a basis for the control of motor drives.

      • KCI등재

        Control of Electrically Excited Synchronous Motors with a Low Switching Frequency

        Qing-qing Yuan,Xiao-jie Wu,Peng Dai,Xiao Fu 전력전자학회 2012 JOURNAL OF POWER ELECTRONICS Vol.12 No.4

        The switching frequency of the power electronic devices used in large synchronous motor drives is usually kept low (less than 1 kHz) to reduce the switching losses and to improve the converter power capability. However, this results in a couple of problems, e.g. an increase in the harmonic components of the stator current, and an undesired cross-coupling between the magnetization current component (im) and the torque component (it). In this paper, a novel complex matrix model of electrically excited synchronous motors (EESM) was established with a new control scheme for coping with the low switching frequency issues. First, a hybrid observer was proposed to identify the instantaneous fundamental component of the stator current, which results in an obvious reduction of both the total harmonic distortion (THD) and the low order harmonics. Then, a novel complex current controller was designed to realize the decoupling between im and it. Simulation and experimental results verify the effectiveness of this novel control system for EESM drives.

      • Novel and Effective Almagate Enema for Hemorrhagic Chronic Radiation Proctitis and Risk Factors for Fistula Development

        Yuan, Zi-Xu,Ma, Teng-Hui,Zhong, Qing-Hua,Wang, Huai-Ming,Yu, Xi-Hu,Qin, Qi-Yuan,Chu, Li-Li,Wang, Lei,Wang, Jian-Ping Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.2

        Radiation proctitis is a common complication after radiotherapy for pelvic malignant tumors. This study was conducted to assess the efficacy of novel almagate enemas in hemorrhagic chronic radiation proctitis (CRP) and evaluate risk factors related to rectal deep ulcer or fistula secondary to CRP. All patients underwent a colonoscopy to confirm the diagnosis of CRP and symptoms were graded. Typical endoscopic and pathological images, risk factors, and quality of life were also recorded. A total of 59 patients were enrolled. Gynecological cancers composed 93.1% of the primary malignancies. Complete or obvious reduction of bleeding was observed in 90% (53/59) patients after almagate enema. The mean score of bleeding improved from 2.17 to 0.83 (P<0.001) after the enemas. The mean response time was 12 days. No adverse effects were found. Moreover, long-term successful rate in controlling bleeding was 69% and the quality of life was dramatically improved (P=0.001). The efficacy was equivalent to rectal sucralfate, but the almagate with its antacid properties acted more rapidly than sucralfate. Furthermore, we firstly found that moderate to severe anemia was the risk factor of CRP patients who developed rectal deep ulcer or fistulas (P= 0.015). We also found abnormal hyaline-like thick wall vessels, which revealed endarteritis obliterans and the fibrosis underlying this disease. These findings indicate that almagate enema is a novel effective, rapid and well-tolerated method for hemorrhagic CRP. Moderate to severe anemia is a risk factor for deep ulceration or fistula.

      • KCI등재

        Sublethal effects of beta-cypermethrin on the bird cherry-oat aphid Rhopalosiphum padi (Hemiptera: Aphididae)

        Qing-Qing Zhang,Wen-Qiang Li,Zeng-Bin Lu,Li-Li Li,Yi Yu,Chao Li,Xing-Yuan Men 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.3

        Rhopalosiphum padi is a sap-sucking aphid and an important pest of wheat that causes considerable yield loss. Beta-cypermethrin, a synthetic pyrethroid pesticide, has a broad insecticide spectrum and is considered effective for aphid control, while its residual concentrations may have sublethal effects on R. padi. Here, the sublethal effects of beta-cypermethrin on R. padi were conducted under laboratory conditions. The acute toxicity test showed that LC 10 , LC 20 , and LC 25 of beta-cypermethrin to R. padi adults were 0.003, 0.031 and 0.079 mg L −1 , respectively. The pre-adult survival rate was significantly reduced by all three concentrations. LC 20 significantly extended the development duration of 1st instar nymphs, pre-oviposition period, and oviposition period of R. padi. The adult longevity was also reduced by LC 25 . However, the fecundity did not differ between the betacypermethrin treatment and control. For life table parameters, both the finite rate (λ) and intrinsic rate of increase (r) decreased at LC 10 and LC 20 , as well as the net reproductive rate (R 0 ) reduced at LC 10 and LC 25 , while mean generation time (T) increased at LC 20 . Thus, at the concentrations of beta-cypermethrin tested here, there were negative impacts on R. padi fitness by decreased pre-adult survival rate, λ, r, and R 0 , and delayed the development of some stages and increased T.

      • KCI등재

        Use of In Vivo-Induced Antigen Technology to Identify In Vivo-Expressed Genes of Campylobacter jejuni During Human Infection

        ( Yuan Qing Hu ),( Jin Lin Huang ),( Qiu Chun Li ),( Yu Wei Shang ),( Fang Zhe Ren ),( Yang Jiao ),( Zhi Cheng Liu ),( Zhi Ming Pan ),( Xin An Jiao ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.3

        Campylobacter jejuni is a prevalent foodborne pathogen worldwide. Human infection by C. jejuni primarily arises from contaminated poultry meats. Genes expressed in vivo may play an important role in the pathogenicity of C. jejuni. We applied an immunoscreening method, in vivo-induced antigen technology (IVIAT), to identify in vivo-induced genes during human infection by C. jejuni. An inducible expression library of genomic proteins was constructed from sequenced C. jejuni NCTC 11168 and was then screened using adsorbed, pooled human sera obtained from clinical patients. We successfully identified 24 unique genes expressed in vivo. These genes were implicated in metabolism, molecular biosynthesis, genetic information processing, transport, and other processes. We selected six genes with different functions to compare their expression levels in vivo and in vitro using real-time RT-PCR. The results showed that the selected six genes were significantly upregulated in vivo but not in vitro. In short, these identified in vivo-induced genes may contribute to human infection of C. jejuni, some of which may be meaningful vaccine candidate antigens or diagnosis serologic markers for campylobacteriosis. IVIAT may present a significant and efficient method for understanding the pathogenicity mechanism of Campylobacter and for finding targets for its prevention and control.

      • KCI등재

        Blasting vibration velocity prediction based on least squares support vector machine with particle swarm optimization algorithm

        Qing Yuan,Shihong Zhai,Li Wu,Peishuai Chen,Yuchun Zhou,Qingjun Zuo 한국자원공학회 2019 Geosystem engineering Vol.22 No.5

        In blasting excavation engineering of super-large section underground caverns, blasting vibration velocity prediction accuracy is affected by many factors. In order to improve its accuracy, the key problem is to obtain these affect factors comprehensively. In this paper, we innovatively put forward eight independent factors in the aspect of explosion source conditions, engineering conditions and propagation medium conditions. These factors have complex non-linear relationship with blasting vibration velocity. We consider particle swarm optimization (PSO) algorithm and least squares support vector machine (LS-SVM) method for prediction (PSO-LSSVM). In this way, how to determine the characteristic parameters and calculation rules of PSO-LSSVM method is another key problem, which has been innovatively solved in this paper. Then it is used to predict the blasting vibration velocity of underground water-sealed LPG caverns in Yantai, China, and compared with Sadov’s formula (SA), fuzzy neural network (FNN) and LS-SVM methods. The results indicate that relative errors of PSO-LSSVM are significantly less than LS-SVM, FNN and SA. Whether global root mean square relative error for prediction accuracy, or group number meeting requirement of error threshold value for generalization performance, the PSO-LSSVM method is superior to LS-SVM, FNN and SA with best availability and superiority.

      • KCI등재

        Current Decoupling Control for the Three-level PWM Rectifier with a Low Switching Frequency

        Qing-qing YUAN,Kun XIA 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.1

        Three-level PWM rectifiers applied in medium voltage applications usually operate at low switching frequency to keep the dynamic losses under permitted level. However, low switching frequency brings a heavy cross-coupling between the current components id and iq with a poor dynamic system performance and a harmonic distortion in the grid-connecting current. To overcome these problems, a mathematical model based on complex variables of the three-level voltage source PWM rectifier is firstly established, and the reasons of above issues resulted from low switching frequency have been analyzed using modern control theory. Then, a novel control strategy suitable for the current decoupling control based on the complex variables for id and iq is designed here. The comparisons between this kind of control strategy and the normal PI method have been carried out. MATLAB and experimental results are given in detail.

      • SCIESCOPUS

        Risk assessment of water inrush in karst tunnels based on a modified grey evaluation model: Sample as Shangjiawan Tunnel

        Yuan, Yong-cai,Li, Shu-cai,Zhang, Qian-qing,Li, Li-ping,Shi, Shao-shuai,Zhou, Zong-qing Techno-Press 2016 Geomechanics & engineering Vol.11 No.4

        A modified grey clustering method is presented to systematically evaluate the risk of water inrush in karst tunnels. Based on the center triangle whitenization weight function and upper and lower limit measure whitenization weight function, the modified grey evaluation model doesn't have the crossing properties of grey cluster and meets the standard well. By adsorbing and integrating the previous research results, seven influence factors are selected as evaluation indexes. A couple of evaluation indexes are modified and quantitatively graded according to four risk grades through expert evaluation method. The weights of evaluation indexes are rationally distributed by the comprehensive assignment method. It is integrated by the subjective factors and the objective factors. Subjective weight is given based on analytical hierarchy process, and objective weight obtained from simple dependent function. The modified grey evaluation model is validated by Jigongling Tunnel. Finally, the water inrush risk of Shangjiawan Tunnel is evaluated by using the established model, and the evaluation result obtained from the proposed method is agrees well with practical situation. This risk assessment methodology provides a powerful tool with which planners and engineers can systematically assess the risk of water inrush in karst tunnels.

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