Signal processing method based on energy ratio for detecting leakage of SG using EVFM

Xu Wei,Xu Ke-Jun,Yan Xiao-Xue,Yu Xin-Long,Wu Jian-Ping,Xiong Wei 한국원자력학회 2020 Nuclear Engineering and Technology Vol.52 No.8

In the sodium-cooled fast reactor, the steam generator is a heat exchange device between sodium and water, which may cause leakage, resulting in a sodium-water reaction accident, which in turn affects the safe operation of the entire nuclear reactor. To this end, the electromagnetic vortex flowmeter is used to detect leakage of the steam generator and its signal processing method is studied in this paper. The hydraulic experiment was carried out by using water instead of liquid sodium, and the sensor output signal of the electromagnetic vortex flowmeter under different gas injection volumes was collected. The bubble noise signal is reflected by the base line of the sensor output signal. According to the relationship between the proportion of the bubble noise signal in the sensor output signal and the gas injection volume, a signal processing method based on the energy ratio calculation is proposed to detect whether the water contains bubbles. The gas injection experiment of liquid sodium was conducted to verify the effectiveness of the signal processing method in the detection of bubbles in sodium, and the minimum detectable leak rate of water in the steam generator was detected to be 0.2 g/s.

Signal processing method of bubble detection in sodium flow based on inverse Fourier transform to calculate energy ratio

Xu, Wei,Xu, Ke-Jun,Yu, Xin-Long,Huang, Ya,Wu, Wen-Kai Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.9

Electromagnetic vortex flowmeter is a new type of instrument for detecting leakage of steam generator, and the signal processing method based on the envelope to calculate energy ratio can effectively detect bubbles in sodium flow. The signal processing method is not affected by changes in the amplitude of the sensor output signal, which is caused by changes in magnetic field strength and other factors. However, the detection sensitivity of the electromagnetic vortex flowmeter is reduced. To this end, a signal processing method based on inverse Fourier transform to calculate energy ratio is proposed. According to the difference between the frequency band of the bubble noise signal and the flow signal, only the amplitude in the frequency band of the flow signal is retained in the frequency domain, and then the flow signal is obtained by the inverse Fourier transform method, thereby calculating the energy ratio. Using this method to process the experimental data, the results show that it can detect 0.1 g/s leak rate of water in the steam generator, and its performance is significantly better than that of the signal processing method based on the envelope to calculate energy ratio.

Fault-tolerant Control for Linear System Under Sensor Saturation Constraint

Jun-Wei Zhu,Qiao-Qian Zhou,Jianming Xu,Jian-Wei Dong 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.1

An observer-based fault-tolerant control method is proposed for a linear system with sensor saturationconstraint. Considering the linear system with simultaneous actuator faults and sensor faults, the sensor saturation would bring the output measurement error of the system, which would result in the estimation performancedegradation. Firstly, the intermediate estimator is modified to estimate the system states and fault signals at thesimultaneous time, and the fault-tolerant controller is designed based on the estimation to compensate the effectof actuator faults effectively. Through Lyapunov stability analysis, the sufficient conditions are obtained to ensurethe states of closed-loop system to be uniformly ultimately bounded. The effect of sensor saturation error can besuppressed by adjusting some specified parameters directly without introducing any performance index. Finally, theeffectiveness and superiority of the proposed method are verified by a simulation example

Isolation and characterization of a novel Ganoderma lucidum gene that differentially expressed between shaking culture and liquid static culture

Jun-Wei Xu,Wei Zhao,Jian-Jiang Zhong 한국유전학회 2011 Genes & Genomics Vol.33 No.6

Suppression subtractive hybridization (SSH) was preformed to investigate the differences of gene expression between the shaking culture mode and the liquid static culture mode which favors ganoderic acids production in Ganoderma lucidum. One novel gene preferentially expressed in liquid static culture was identified and analyzed. Its full length cDNA sequence and the 5'-flanking region were then obtained by rapid amplification of cDNA ends (RACE) and self-formed adaptor PCR (SEFA-PCR), respectively. Nucleotide sequence of the gene is not homologous to any of the known Ganoderma genes. The sequence analysis revealed that the open reading frame of this gene encodes a protein of 371 amino acids that has high homology with the mitogen-activated protein kinase (MAPK) of other five species-Postia (97%), Coprinopsis (91%), Neurospora (86%), Aspergillus (83%), and Saccharomyces (80%)-so that it can be defined as a G. lucidum MAPK gene (GenBank accession number: JF781125). Computer assisted analysis revealed that this new G. lucidum MAPK gene contains thirteen exons and twelve introns. The quantitative real-time RT-PCR (qRT-PCR) analysis showed that this new gene had a much higher expression level in liquid static culture than in traditional shaking culture. Results of this research established a good foundation for further study on the functions of the G. lucidum MAPK at the molecular level.

Integrated Voltage and Power Flow Management Considering the Cost of Operation in Active Distribution Networks

Wei Wei,Tao Xu,Xiaoxue Wang,Chengshan Wang,Lingxu Guo,Jun Lin,Tianchu Li 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.2

The increasing penetration of distributed energy resources on the distribution networks have brought a number of technical impacts where voltage and thermal variations have been identified as the dominant effects. Active network management in distribution networks aims to integrate distributed energy resources with flexible network management so that distributed energy resources are organized to make better use of existing capacity and infrastructure. This paper propose active solutions which aims to solve the voltage and thermal issues in a distributed manner utilizing a collaborative approach. The proposed algorithms have been fully tested on a distribution network with distributed generation units.

A metal oxide TFT gate driver with a single negative power source employing a boosting module

Yangang Xu,Jun-Wei Chen,Wen-Xing Xu,Lei Zhou,Wei-Jing Wu,Jianhua Zou,Miao Xu,Lei Wang,Junbiao Peng 한국정보디스플레이학회 2020 Journal of information display Vol.21 No.1

This paper presents a new gate driver integrated by In-Zn-O thin-film transistors (IZO TFTs) with the etch stop layer (ESL) structure, in which only a single negative power source is used on account of a new boosting module. The boosting module is controlled only by the VIN signal for generating a lower level than VSS. The proposed gate driver with 15 stages is fabricated through the IZO TFT process on a glass substrate to verify its function. The experiment results showed that the proposed gate driver can successfully output full-swing waveforms with resistive load RL=2 kΩ and capacitive load CL=30 pF at the 16.7 and 66.7 kHz clock frequencies, and can also output as small as 3.2 μs pulse width with little distortion, revealing good stability.

An Efficient Synthesis of Substituted Furans by Cupric Halide-Mediated Intramolecular Halocyclization of 2-(1-Alkynyl)-2-alken-1-ones

Fu, Wei-Jun,Xu, Feng-Juan,Guo, Wen-Bo,Zhu, Mei,Xu, Chen Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.3

An efficient synthesis of 3-halofurans by the intramolecular cyclization of 2-(1-alkynyl)-2-alken-1-ones with cupric halide has been developed. A broad range of 3-chloro- and 3-bromofuran derivatives could be obtained in the present method in moderate to good yields. The 3-halofuran derivatives are potential synthetic intermediates for amplification of molecular complexity.

Expression profiles of circular RNAs in sheep skeletal muscle

Cao, Yang,You, Shuang,Yao, Yang,Liu, Zhi-Jin,Hazi, Wureli,Li, Cun-Yuan,Zhang, Xiang-Yu,Hou, Xiao-Xu,Wei, Jun-Chang,Li, Xiao-Yue,Wang, Da-Wei,Chen, Chuang-Fu,Zhang, Yun-Feng,Ni, Wei,Hu, Sheng-Wei Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.10

Objective: Circular RNAs (circRNAs) are a newfound class of non-coding RNA in animals and plants. Recent studies have revealed that circRNAs play important roles in cell proliferation, differentiation, autophagy and apoptosis during development. However, there are few reports about muscle development-related circRNAs in livestock. Methods: RNA sequencing analysis was employed to identify and annotate circRNAs from longissimus dorsi of sheep. Reverse transcription followed by real-time quantitative (q) polymerase chain reaction (PCR) analysis verified the presence of these circRNAs. Targetscan7.0 and miRanda were used to analyse the interaction of circRNA-microRNA (miRNA). To investigate the function of circRNAs, an experiment was conducted to perform enrichment analysis hosting genes of circRNAs using gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathways. Results: About 75.5 million sequences were obtained from RNA libraries of sheep skeletal muscle. These sequences were mapped to 729 genes in the sheep reference genome. We identified 886 circRNAs, including numerous circular intronic RNAs and exonic circRNAs. Reverse transcription PCR (RT-PCR) and DNA sequencing analysis confirmed the presence of several circRNAs. Real-Time RT-PCR analysis exhibited resistance of sheep circRNAs to RNase R digestion. We found that many circRNAs interacted with muscle-specific miRNAs involved in growth and development of muscle, especially circ776. The GO and KEGG enrichment analysis showed that hosting genes of circRNAs was involved in muscle cell development and signaling pathway. Conclusion: The study provides comprehensive expression profiles of circRNAs in sheep skeletal muscle. Our study offers a large number of circRNAs to facilitate a better understanding of their roles in muscle growth. Meanwhile, we suggested that circ776 could be analyzed in future study.

¹H-Nuclear Magnetic Resonance-Based Plasma Metabolic Profiling of Dairy Cows with Fatty Liver

Xu, Chuang,Sun, Ling-wei,Xia, Cheng,Zhang, Hong-you,Zheng, Jia-san,Wang, Jun-song Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.2

Fatty liver is a common metabolic disorder of dairy cows during the transition period. Historically, the diagnosis of fatty liver has involved liver biopsy, biochemical or histological examination of liver specimens, and ultrasonographic imaging of the liver. However, more convenient and noninvasive methods would be beneficial for the diagnosis of fatty liver in dairy cows. The plasma metabolic profiles of dairy cows with fatty liver and normal (control) cows were investigated to identify new biomarkers using $^1H$ nuclear magnetic resonance. Compared with the control group, the primary differences in the fatty liver group included increases in ${\beta}$-hydroxybutyric acid, acetone, glycine, valine, trimethylamine-N-oxide, citrulline, and isobutyrate, and decreases in alanine, asparagine, glucose, ${\gamma}$-aminobutyric acid glycerol, and creatinine. This analysis revealed a global profile of endogenous metabolites, which may present potential biomarkers for the diagnosis of fatty liver in dairy cows.

Modulator of surface plasmon polariton based cycle branch graphene waveguide

Jun Zhu,Zhengjie Xu,Wenju Xu,Duqu Wei 한국탄소학회 2018 Carbon Letters Vol.25 No.-

At present, an important research area is the search for materials that are compatible with CMOS technology and achieve a satisfactory response rate and modulation efficiency. A strong local field of graphene surface plasmon polariton (SPP) can increase the interaction between light and graphene, reduce device size, and facilitate the integration of materials with CMOS. In this study, we design a new modulator of SPP-based cycle branch graphene waveguide. The structure comprises a primary waveguide of graphene–LiNbO3–graphene, and a secondary cycle branch waveguide is etched on the surface of LiNbO3. Part of the incident light in the primary waveguide enters the secondary waveguide, thus leading to a phase difference with the primary waveguide as reflected at the end of the branch and interaction coupling to enhance output light intensity. Through feature analysis, we discover that the area of the secondary waveguide shows significant localized fields and SPPs. Moreover, the cycle branch graphene waveguide can realize gain compensation, reduce transmission loss, and increase transmission distance. Numerical simulations show that the minimum effective mode field area is about 0.0130l2, the gain coefficient is about 700 cm–1, and the quality factor can reach 150. The structure can realize the mode field limits of deep subwavelength and achieve a good comprehensive performance.