Monte Carlo Method and Quantile Regression for Uncertainty Analysis of Wind Power Forecasting Based on Chaos-LS-SVM

Xin Zhao,Chao Ge,Fangfang Ji,Yajuan Liu 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.11

In the paper, the chaos least squares support vector machine algorithm (Chaos-LS-SVM) is applied. To conduct uncertainty analysis of wind power forecasting, two forecasting algorithms of the probabilistic uncertainty analysis based on the Monte Carlo method and the quantile regression analysis based on Chaos-LS-SVM are discussed. The effectiveness and superiority of the two uncertainty analysis methods in the confidence level of 95%, 90%, and 85% are discussed by simulation analysis, and the confidence interval is given in the corresponding confidence level. The prediction interval coverage probability (PICP) and the prediction interval normalized average width (PINAW) of the two uncertainty methods are compared. In the time scale of 1h-ahead, 4h-ahead, and 6h-ahead, the probabilistic uncertainty analysis based on the Monte Carlo method is suitable. In the time scale of 24h-ahead, the quantile regression analysis based on Chaos-LS-SVM is superior.

Dietary Lactobacillus plantarum GB805 supplementation improves growth performance and nutrient digestibility in weaning pigs

Liu, Wen Chao Liu, Jung Sun Kang and In Ho Ki Chao,Kang, Jung Sun,Kim, In Ho Agricultural Research Communication Center 2018 Indian Journal of Animal Research Vol.52 No.-

<P>A total of 60 weaned pigs with initial body weight (BW) of 8.51 ± 0.42 kg (28 d of age) were randomly divided into 2 groups of 30 each consisted of 6 pens with 2 gilts and 3 borrows and supplemented (treatment) 5.3×108 cfu/kg Lactobacillus plantarum GB805 in addition to basal diet offered during d 0 to 14 and d 15 to 42 (control). During the total trial period or different phases of trial, pigs fed L. plantarum diet had a higher (P less than 0.05) ADG, ADFI and feed efficiency. At the end of experiment, dietary L. plantarum supplementation improved (P less than 0.05) the apparent total tract digestibility of dry matter, nitrogen and the fecal Lactobacillus populations (P less than 0.05) while the fecal E.coli populations were decreased (P less than 0.05). In conclusion, dietary supplementation of L. plantarum GB805 had positive influence on growth rate, nutrient digestibility and gut microbial balance and its supplementation recommended to weaning pigs.</P>

A Fault Diagnostic Method for Position Sensor of Switched Reluctance Wind Generator

Chao Wang,Xiao Liu,Hui Liu,Zhe Chen 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.1

Fast and accurate fault diagnosis of the position sensor is of great significance to ensure the reliability as well as sensor fault tolerant operation of the Switched Reluctance Wind Generator (SRWG). This paper presents a fault diagnostic scheme for a SRWG based on the residual between the estimated rotor position and the actual output of the position sensor. Extreme Learning Machine (ELM), which could build a nonlinear mapping among flux linkage, current and rotor position, is utilized to design an assembled estimator for the rotor position detection. The data for building the ELM based assembled position estimator is derived from the magnetization curves which are obtained from Finite Element Analysis (FEA) of an SRWG with the structure of 8 stator poles and 6 rotor poles. The effectiveness and accuracy of the proposed fault diagnosis method are verified by simulation at various operating conditions. The results provide a feasible theoretical and technical basis for the effective condition monitoring and predictive maintenance of SRWG.

Disturbance Compensation based Discrete-time Sliding Mode Control with a Reference Trajectory Generator

Chao Liu,Yangmin Li,Sukun Tian,Haifeng Ma 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.12

A novel disturbance compensation based sliding mode reaching law with a reference trajectory generator is presented in this work. Unlike existing similar researches, a reference trajectory generator is added to the reachinglaw to obtain the target evolution of the switching function. Meanwhile, a high order disturbance estimator is utilized to achieve accurate disturbance rejection. Additionally, by using the nonlinear functions, the controllerparameters can be adaptively adjusted in a wise manner. The main merit of the presented method is that it is capable of ensuring a much smaller ultimate bound of the switching function, i.e., O(Tn+1) order accuracy and n is a positiveinteger, better system robustness, and improved control accuracy. Moreover, system dynamics, including the system states, are theoretically analyzed. The performance improvement of the presented method is verified through a realsimulation study.

Reachability and Observability of Switched Linear Systems with Continuous-Time and Discrete-Time Subsystems

Chao Liu,Chuandong Li 제어·로봇·시스템학회 2013 International Journal of Control, Automation, and Vol.11 No.1

In this paper, the reachability and observability criteria of switched linear systems with con-tinuous-time and discrete-time subsystems are obtained. These criteria show that the reachable set may not be a subspace in the state space, because of the existence of discrete-time subsystems. Therefore, the definition of span reachability is proposed. Moreover, we demonstrate that the reachable set is equivalent to subspace if the discrete-time subsystems are reversible. The subspace algorithms for span reachability and unobservability are provided. One example is introduced to illustrate the effectiveness of the proposed criteria.

The injector-based regenerative supercritical organic Rankine cycle

Chao Liu,Xi Wang,Hong Gao,Cheng Zhang,Chao He 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.5

In order to improve the thermodynamic performance of the Supercritical organic Rankine cycle (SORC), the regenerative supercritical organic Rankine cycle with an injector (RORC) is presented. For the moderate temperature of waste heat, the thermodynamic performance of RORC and SORC are investigated by using the working fluid R123. The effects of extraction pressure, expander inlet temperature, expander inlet pressure and condensing temperature on the net power output and the thermal efficiency have been analyzed. The net power output of RORC is greater than one of SORC when the extraction pressure is lower than 0.45 MPa. When the extraction pressure is 0.6 MPa, the efficiency of RORC reaches the maximum (16.06%), which is 0.66% higher than one of SORC. This reveals that the performance of RORC is better than that of SORC.

Stabilization of Oscillating Neural Networks with Time-Delay by Intermittent Control

Chao Liu,Chuandong Li,Shukai Duan 제어·로봇·시스템학회 2011 International Journal of Control, Automation, and Vol.9 No.6

In this paper, we study the exponential stabilization of oscillating neural networks with time-delay through the process called intermittent control. Some exponential stability criteria for the controlled neural networks are established by Lyapunov function and matrix inequality analysis technique. The present results allow us to estimate legitimately the feasible control region of control parameters. Nu-merical example is also given to show the effectiveness of our proposed results.

Effects of dietary xylanase supplementation on performance and functional digestive parameters in broilers fed wheat-based diets

Liu, Wen-Chao,Kim, In-Ho Elsevier 2017 Poultry science Vol.96 No.3

<P>This experiment was conducted to evaluate dietary xylanase supplementation in broilers wheat-based diets on performance and functional digestive parameters including ileal digesta viscosity, apparent ileal digestibility, intestinal morphology and microflora, digestive enzyme activities, and excreta odor content. A total of 600 1-day-old Ross 308 male broilers with an initial average BW of 45 +/- 0.6 g were randomly allotted into 4 treatments with 10 replicate pens per treatment and 15 broilers in each pen for 35 d. The 4 dietary treatments were wheat-based diets and supplemented with 0, 1,875, 3,750, and 5,625 XU/kg xylanase. Xylanase supplementation improved (linear, P < 0.05) the body weight gain and decreased (linear, P < 0.05) the feed conversion ratio during d 1 to 18 and for the duration of the experiment. Dietary supplementation of xylanase led to a decrease (linear, P < 0.01) in ileal digesta viscosity. The apparent ileal digestibility of dry matter (DM), crude protein (CP), gross energy, and most amino acids (with the exception of Ile, Phe, Asp, Glu, and Pro) were increased (linear, P < 0.05) by xylanase supplementation. Increasing the dietary xylanase levels improved (linear, P < 0.05) the villus height and the ratio of villus height to crypt depth of the duodenum, jejunum, and ileum. In addition, inclusion of xylanase increased (linear, P < 0.05) the Lactobacillus numbers in the ileum and cecum, while decreased the ileal E. coli counts (linear, P < 0.01) and cecal E. coli populations (linear, P < 0.01; quadratic, P < 0.05). There were no significant differences (P > 0.05) in trypsin, amylase, and protease activities of small intestine among dietary treatments. Furthermore, xylanase supplementation reduced excreta NH3 (linear, P < 0.05; quadratic, P < 0.05) and total mercaptan (R. SH) (linear, P < 0.01) concentration. Taken together, dietary xylanase supplementation in broilers wheat-based diets had beneficial effects on growth performance, apparent ileal digestibility of nutrients, intestinal morphology, and microflora balance. Furthermore, the xylanase could reduce the ileal digesta viscosity and excreta odor contents.</P>

Molecular Cloning and Bioinformatic Analysis of SPATA4 Gene

Liu, Shang-Feng,Ai, Chao,Ge, Zhong-Qi,Liu, Hai-Luo,Liu, Bo-Wen,He, Shan,Wang, Zhao Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.6

Full-length cDNA sequences of four novel SPATA4 genes in chimpanzee, cow, chicken and ascidian were identified by bioinformatic analysis using mouse or human SPATA4 cDNA fragment as electronic probe. All these genes have 6 exons and have similar protein molecular weight and do not localize in sex chromosome. The mouse SPATA4 sequence is identified as significantly changed in cryptorchidism, which shares no significant homology with any known protein in swissprot databases except for the homologous genes in various vertebrates. Our searching results showed that all SPATA4 proteins have a putative conserved domain DUF1042. The percentages of putative SPATA4 protein sequence identity ranging from 30% to 99%. The high similarity was also found in 1 kb promoter regions of human, mouse and rat SPATA4 gene. The similarities of the sequences upstream of SPATA4 promoter also have a high proportion. The results of searching SymAtlas (http://symatlas.gnf.org/SymAtlas/) showed that human SPATA4 has a high expression in testis, especially in testis interstitial, leydig cell, seminiferous tubule and germ cell. Mouse SPATA4 was observed exclusively in adult mouse testis and almost no signal was detected in other tissues. The pI values of the protein are negative, ranging from 9.44 to 10.15. The subcellular location of the protein is usually in the nucleus. And the signal peptide possibilities for SPATA4 are always zero. Using the SNPs data in NCBI, we found 33 SNPs in human SPATA4 gene genomic DNA region, with the distribution of 29 SNPs in the introns. CpG island searching gives the data about CpG island, which shows that the regions of the CpG island have a high similarity with each other, though the length of the CpG island is different from each other.This research is a fundamental work in the fields of the bioinformational analysis, and also put forward a new way for the bioinformatic analysis of other genes.

Local Heating from Silver Nanoparticles and Its Effect on the Er3+ Upconversion in Oxyfluoride Glasses : Local Heating from Silver Nanoparticles and Its Effect

Liu, Chao,Heo, Jong Wiley (Blackwell Publishing) 2010 JOURNAL OF THE AMERICAN CERAMIC SOCIETY - Vol.93 No.10