Fault Current Analysis of Type-3 Wind Turbine Considering Dynamic Influence of Phase Locked Loop

Xiaomeng Yu,Yuanzhu Chang,Jiabing Hu,Lei Shang 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

As Type-3 wind turbine (WT) has already become a vital source in power system, analyzing its fault current is necessary. Although phase-angle jump of stator voltage always occurs during short circuit, it is neglected in existing research and the influence of phase locked loop (PLL) on fault current is still unclear. In this paper, an analytical model of Type-3 WT considering both magnitude drop and phase-angle jump is first developed. Then, the variable-frequency phenomenon of fault current component is discovered by comparing the results of modal analysis and Hilbert-Huang Transformation (HHT). Moreover, the dominant branch causing this phenomenon is extracted so that the whole system can be decomposed into a linear subsystem and a nonlinear subsystem. Based on these subsystems, an analytical expression of fault current is deduced and validated. The conclusion of this paper indicates that the variable-frequency phenomenon may result in protective relays’ maloperation.

Inhibitory Abilities of Bacillus Isolates and Their Culture Filtrates against the Gray Mold Caused by Botrytis cinerea on Postharvest Fruit

Xiaomeng Chen,Yajie Wang,Yu Gao,Tongguo Gao,Dongdong Zhang 한국식물병리학회 2019 Plant Pathology Journal Vol.35 No.5

Botrytis cinerea, a major phytopathogenic fungus, has been reported to infect more than 200 crop species worldwide, and it causes massive losses in yield. The aim of this study was to evaluate the inhibitory abilities and effects of Bacillus amyloliquefaciens RS-25, Bacillus licheniformis MG-4, Bacillus subtilis Z-14, and Bacillus subtilis Pnf-4 and their culture filtrates and extracts against the gray mold caused by B. cinerea on postharvest tomato, strawberry, and grapefruit. The results revealed that the cells of Z-14, culture filtrate of RS- 25, and cells of Z-14 showed the strongest biocontrol activity against the gray mold on the strawberry, grape, and tomato fruit, respectively. All the strains produced volatile organic compounds (VOCs), and the VOCs of Pnf-4 displayed the highest inhibition values. Based on headspace solid-phase microextraction in combination with gas chromatography-mass spectrometry, esters accounted for the largest percentage of the VOCs produced by RS-25, MG-4, Z-14, and Pnf-4 (36.80%, 29.58%, 30.78%, and 36.26%, respectively). All the strains showed potent cellulase and protease activities, but no chitinase activity. RS-25, Z-14, and MG-4, but not Pnf-4, grew on chrome azurol S agar, and an orange halo was formed around the colonies. All the strains showed biofilm formation, fruit colonization, and lipopeptide production, which may be the main modes of action of the antagonists against B. cinerea on the fruit. This study provides the basis for developing natural biocontrol agents against the gray mold caused by B. cinerea on postharvest fruit.

Inhibitory Abilities of Bacillus Isolates and Their Culture Filtrates against the Gray Mold Caused by Botrytis cinerea on Postharvest Fruit

Chen, Xiaomeng,Wang, Yajie,Gao, Yu,Gao, Tongguo,Zhang, Dongdong The Korean Society of Plant Pathology 2019 Plant Pathology Journal Vol.35 No.5

Botrytis cinerea, a major phytopathogenic fungus, has been reported to infect more than 200 crop species worldwide, and it causes massive losses in yield. The aim of this study was to evaluate the inhibitory abilities and effects of Bacillus amyloliquefaciens RS-25, Bacillus licheniformis MG-4, Bacillus subtilis Z-14, and Bacillus subtilis Pnf-4 and their culture filtrates and extracts against the gray mold caused by B. cinerea on postharvest tomato, strawberry, and grapefruit. The results revealed that the cells of Z-14, culture filtrate of RS-25, and cells of Z-14 showed the strongest biocontrol activity against the gray mold on the strawberry, grape, and tomato fruit, respectively. All the strains produced volatile organic compounds (VOCs), and the VOCs of Pnf-4 displayed the highest inhibition values. Based on headspace solid-phase microextraction in combination with gas chromatography-mass spectrometry, esters accounted for the largest percentage of the VOCs produced by RS-25, MG-4, Z-14, and Pnf-4 (36.80%, 29.58%, 30.78%, and 36.26%, respectively). All the strains showed potent cellulase and protease activities, but no chitinase activity. RS-25, Z-14, and MG-4, but not Pnf-4, grew on chrome azurol S agar, and an orange halo was formed around the colonies. All the strains showed biofilm formation, fruit colonization, and lipopeptide production, which may be the main modes of action of the antagonists against B. cinerea on the fruit. This study provides the basis for developing natural biocontrol agents against the gray mold caused by B. cinerea on postharvest fruit.

Software Pipeline–Based Partitioning Method with Trade-Off between Workload Balance and Communication Optimization

Kai Huang,Min Yu,Xiaomeng Zhang,Rongjie Yan,Xiaolang Yan,Zhili Liu,Siwen Xiu 한국전자통신연구원 2015 ETRI Journal Vol.37 No.3

For a multiprocessor System-on-Chip (MPSoC) to achieve high performance via parallelism, we must consider how to partition a given application into different components and map the components onto multiple processors. In this paper, we propose a software pipeline–based partitioning method with cyclic dependent task management and communication optimization. During task partitioning, simultaneously considering computation load balance and communication optimization can cause interference, which leads to performance loss. To address this issue, we formulate their constraints and apply an integer linear programming approach to find an optimal partitioning result — one that requires a trade-off between these two factors. Experimental results on a reconfigurable MPSoC platform demonstrate the effectiveness of the proposed method, with 20% to 40% performance improvements compared to a traditional software pipeline–based partitioning method.

Comprehensive evaluation of natural enemy dominant species of Breuipalpus oboyats in tea garden in autumn and winter

Zhang Lin,Sun Jiazhao,Wu Xiaomeng,Xu Yu,Bi Shoudong,Zou Yunding 한국곤충학회 2021 Entomological Research Vol.51 No.12

The purpose of this study was to comprehensively evaluate the dominant natural enemies of Breuipalpus oboyats in autumn and winter tea gardens. The relationship between natural enemies and B.oboyats in time and space was studied by niche analysis and geostatistics combined with angular cosine coefficient method. According to the comparison of the sum of closeness index, it is found that the top three natural enemies (from large to small) that are most closely related to B.oboyats in the “Nongkangzao” tea garden are Plexippus paykulli, Clubiona japonicola,and Xysticus ephippiafus; “Pingyangtezao” tea garden are X.ephippiafus, Plexippus setipet,andOxyopes sertatus. In front of the two tea gardens, one of the three natural enemies is the same. The evaluation of the comprehensive closeness index of the two tea gardens shows that the top three natural enemies most closely related to B.oboyats are X.ephippiafus, P.paykulli, and O.sertatus. X.ephippiafus is the most important natural enemy of B.oboyats in tea gardens in autumn and winter; the dominant natural enemies of the same pests in different varieties of tea gardens in the same area are often different.

Curcumin protects against the intestinal ischemia-reperfusion injury: involvement of the tight junction protein ZO-1 and TNF-α related mechanism

Shuying Tian,Ruixue Guo,Sichen Wei,Yu Kong,Xinliang Wei,Weiwei Wang,Xiaomeng Shi,Hongyu Jiang 대한생리학회-대한약리학회 2016 The Korean Journal of Physiology & Pharmacology Vol.20 No.2

Present study aimed to investigate the effect of curcumin-pretreatment on intestinal I/R injury and on intestinal mucosa barrier. Thirty Wistar rats were randomly divided into: sham, I/R, and curcumin groups (n=10). Animals in curcumin group were pretreated with curcumin by gastric gavage (200 mg/kg) for 2 days before I/R. Small intestine tissues were prepared for Haematoxylin & Eosin (H&E) staining. Serum diamine oxidase (DAO) and tumor necrosis factor (TNF)-α levels were measured. Expression of intestinal TNF-α and tight junction protein (ZO-1) proteins was detected by Western blot and/or immunohistochemistry. Serum DAO level and serum and intestinal TNF-α leves were significantly increased after I/R, and the values were markedly reduced by curcumin pretreatment although still higher than that of sham group (p<0.05 or p<0.001). H&E staining showed the significant injury to intestinal mucosa following I/R, and curcumin pretreatment significantly improved the histological structure of intestinal mucosa. I/R insult also induced significantly down-regulated expression of ZO-1, and the effect was dramatically attenuated by curcumin-pretreatment. Curcumin may protect the intestine from I/R injury through restoration of the epithelial structure, promotion of the recovery of intestinal permeability, as well as enhancement of ZO-1 protein expression, and this effect may be partly attributed to the TNF-α related pathway.

Curcumin protects against the intestinal ischemia-reperfusion injury: involvement of the tight junction protein ZO-1 and TNF-α related mechanism

Tian, Shuying,Guo, Ruixue,Wei, Sichen,Kong, Yu,Wei, Xinliang,Wang, Weiwei,Shi, Xiaomeng,Jiang, Hongyu The Korean Society of Pharmacology 2016 The Korean Journal of Physiology & Pharmacology Vol.20 No.2

Present study aimed to investigate the effect of curcumin-pretreatment on intestinal I/R injury and on intestinal mucosa barrier. Thirty Wistar rats were randomly divided into: sham, I/R, and curcumin groups (n=10). Animals in curcumin group were pretreated with curcumin by gastric gavage (200 mg/kg) for 2 days before I/R. Small intestine tissues were prepared for Haematoxylin & Eosin (H&E) staining. Serum diamine oxidase (DAO) and tumor necrosis factor (TNF)-${\alpha}$ levels were measured. Expression of intestinal TNF-${\alpha}$ and tight junction protein (ZO-1) proteins was detected by Western blot and/or immunohistochemistry. Serum DAO level and serum and intestinal TNF-${\alpha}$ leves were significantly increased after I/R, and the values were markedly reduced by curcumin pretreatment although still higher than that of sham group (p<0.05 or p<0.001). H&E staining showed the significant injury to intestinal mucosa following I/R, and curcumin pretreatment significantly improved the histological structure of intestinal mucosa. I/R insult also induced significantly down-regulated expression of ZO-1, and the effect was dramatically attenuated by curcumin-pretreatment. Curcumin may protect the intestine from I/R injury through restoration of the epithelial structure, promotion of the recovery of intestinal permeability, as well as enhancement of ZO-1 protein expression, and this effect may be partly attributed to the TNF-${\alpha}$ related pathway.

Effects of Lactobacillus plantarum SCS2 on blood glucose level in hyperglycemia mice model

Xiao Meng,Yu Qian,Li-Shi Jiang,Jin-Mei Kang,Yan Chen,Juan Wang,Shu-Kun Liu,Zhen-Ming Che,Xin Zhao 한국응용생명화학회 2016 Applied Biological Chemistry (Appl Biol Chem) Vol.59 No.1

In this study, the hyperglycemia mice model was established with 1-week high sugar and fat diet plus with 70 mg/kg body weight of streptozotocin injection for 3 days. Sixty male Kunming mice of 3 weeks old in a specific-pathogen-free grade were divided into six groups randomly, which includes normal group (NG), prevention group (PG), treatment group for low dose (TGL), middle dose (TGM), high dose (TGH), and model group (MG). NG and MG mice were fed with sterile physiological saline (10 mL/kg body weight). PG mice were fed with the concentration of 6.0 × 109 CFU/mL L. plantarum SCS2 suspensions from the second to third week. TGL, TGM, and TGH mice were fed with the concentration of 2.0 × 109, 4.0 × 109, and 6.0 × 109 CFU/mL L. plantarum SCS2 suspensions (10 mL/kg body weight), respectively from fourth to tenth week. The results showed that the fasting and postprandial 2 h blood glucose levels of TGH mice were reduced by L. plantarum SCS2 significantly (p < 0.05) as compared with MG. The body weight of TGH mice came to normal level at tenth week. Content of K+ in plasma of TGH mice was increased and contents of Na+ and Cl− in the plasma of TGH mice were decreased as compared with MG. Meanwhile, content of glycogen in TGH mice was reduced. However, the effect of L. plantarum SCS2 on the prevention of hyperglycemia in PG mice was not significant as compared with NG mice during the experiment. These results suggested that L. plantarum SCS2 showed a hypoglycemic effect on hyperglycemic mice model.