Common mode leakage current analysis for Transformerless PV system with long DC side cables

Xiaomei Song,Wenjie Chen,Yang Xuan,Bin Zhang,Jiao Zhang 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Due to the advantages of high efficiency and low cost, grid connected inverter based transformerless PV systems have been widespread during the last two decades. The key problem, which arises in absence of galvanic isolation, is the presence of a common mode (CM) leakage current on both AC and DC side of the inverter. In this paper, the influence of long DC side cable to the CM leakage current is taken into account for the first time. Moreover, an improved pai-structure model of the PV panel is proposed. It differs from the traditional single capacitance model in that the panel frame, the mounting rack as well as the connecting wire is all considered. Based upon the proposed model, the common mode leakage current is evaluated in both time domain and frequency domain. Simulation and experimental results give a firm support to the proposed model.

Vitamin D Supplementation is Beneficial for Children with Autism Spectrum Disorder: A Meta-analysis

Liyao Song,Xiaomei Luo,Qing Jiang,Zhi Chen,Lifang Zhou,Dan Wang,Ai Chen 대한정신약물학회 2020 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.18 No.2

Objective: We conducted a meta-analysis of randomized controlled trials to explore whether vitamin D supplementation is beneficial for symptom improvement in children with autism spectrum disorder. Methods: We systematically searched the PubMed database, EMBASE, Cochrane Library, Web of Science, Sino-Med, Wanfang Data, and China National Knowledge Infrastructure mainly up to September 2019. Using a fixed effects model, we calculated the standard mean difference with 95% confidence interval. Furthermore, we analyzed baseline serum 25-hydroxyvitamin D levels and outcome scores including the Social Responsiveness Scale and Child Autism Rating Scale scores after vitamin D supplementation. Results: There was no significant difference in baseline serum 25-hydroxyvitamin D levels among 203 children included from three studies in the meta-analysis. After vitamin D supplementation, the outcome scores in the experimental group were dramatically elevated compared with those in the control group (p = 0.03). Conclusion: Vitamin D supplementation improves the typical symptoms of autism spectrum disorder, as indicated by reduced Social Responsiveness Scale and Child Autism Rating Scale scores; thus, it is beneficial for children with autism spectrum disorder.

Design and Implementation of a High Power Three-Level T-Type Inverter for a Photovoltaic System

Yang Xuan,Mofan Tian,Xiaomei Song,Wenjie Chen,Xu Yang 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Nowadays, the grid-connected photovoltaic systems are an important part of the renewable energy sources, and their performance is getting more and more important. Many reported researches focused on the traditional NPC topology. However, few researches were about the T-type NPC inverter. In this paper, a high power three-phase T-type neutral point clamped grid connected photovoltaic inverter prototype is designed and implemented. The design and implementation procedure of the inverter is discussed in detail. Experimental results showed that the output power of the proposed inverter could reach up to 100kW with unit power factor, while the total harmonic distortion of the grid current was less than 3%. And the total efficiency of the system is measured as 95.6%. The experimental results demonstrated the T-type NPC inverter can operate with a good performance.

Expression of selenium-independent glutathione peroxidase 5 (GPx5) in the epididymis of Small Tail Han sheep

Li, Ruilan,Fan, Xiaomei,Zhang, Tong,Song, Huizi,Bian, Xiaona,Nai, Rile,Li, Jinquan,Zhang, Jiaxin Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.10

Objective: Selenium-independent glutathione peroxidase (GPx5) is specifically expressed in the mammalian epididymis and plays an important role in protecting sperm from reactive oxygen species and lipid peroxidation damage. This study investigates GPx5 expression in the epididymis of Small Tail Han sheep. Methods: GPx5 expression was studied in three age groups: lamb (2 to 3 months), young (8 to 10 months), and adult (18 to 24 months). The epididymis of each age group divided into caput, corpus and cauda, respectively. Analysis the expression quantity of GPx5 in epididymis and testis by real-time fluorescent quantitative polymerase chain reaction and Western blot. Finally, GPx5 protein locating in the epididymis by immunohistochemical. Results: The results demonstrate that in the lamb group, the GPx5 mRNA, but not protein, can be detected. GPx5 mRNA and expressed protein were detected in both the young and adult groups. Moreover, both the mRNA and protein levels of GPx5 were significantly higher in the young group than in other two groups. When the different segments of epididymis were investigated, GPx5 mRNA was expressed in each segment of epididymis regardless of age. Additionally, the mRNA level in the caput was significantly higher than that in corpus and cauda within same age group. The GPx5 protein was in the epithelial cells' cytoplasm. However, GPx5 mRNA and protein were not detected in the testis. Conclusion: These results suggest that GPx5 is mainly expressed in the epididymis of Small Tail Han sheep, and that the expression level of GPx5 is associated with age. Additionally, GPx5 was primarily expressed in the epithelial cells of the caput. Taken together, these studies indicate that GPx5 is expressed in the epididymis in all age grades.

Optimal design of EMI filters for PV system based on parasitic parameter and stability analysis

Jiao Zhang,Wenjie Chen,Bin Zhang,Xiaomei Song,Hao Huang 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Electromagnetic magnetic interference (EMI) issue has become one of the urgent problems to be solved in the photovoltaic (PV) inverter system. Therefore, it should not be ignored. In order to optimize the EMI filter design, high frequency characteristic of a PV system is studied in this paper. A conducted EMI model is proposed. The proposed model take into consider the influences of PV array parameters, DC side cable impedance, inverter parasitic capacitance and the unbalance of AC side impedance. Based upon that model, a passive EMI filter used for the DC side of a PV system is designed and fabricated. And the designing steps have been given thoroughly. To acquire the best performance of the filter, a stabilization analysis based on Routh criterion is also made. Finally, experimental results are presented to verify the efficient of the proposed EMI filter.

Higher Serum C Reactive Protein Determined C Reactive Protein Single-Nucleotide Polymorphisms Are Involved in Inherited Depression

Shiliang Wang,Hua Zhong,Meijuan Lu,Guohua Song,Xiaomei Zhang,Min Lin,Shengliang Yang,Mincai Qian 대한신경정신의학회 2018 PSYCHIATRY INVESTIGATION Vol.15 No.8

Objective_The pathogenesis of depression is not fully understood yet, but studies have suggested higher circulating C reactive protein (CRP) level might relate to depression occurrence. However, due to high variability of patients’ individual condition, the results to date are inconsistent. Considering CRP single-nucleotide polymorphisms (SNPs) could also regulate plasma CRP levels, in the present study, we hypothesized that inherited CRP allelic variations may co-vary with depressive symptomatology. Methods_We recruited 60 depression patients with family depression history and 60 healthy control volunteers into this project. We detected circulation CRP level as well as genome CRP SNPs from participants of this project. Results_We have found a significantly higher circulating CRP level in patients with a positive family history. Furthermore, we also identified some certain inherited CRP SNPs (A allele in rs1417938 and C allele in rs1205) could up regulate serum CRP level and distributed more in depression patients with family history. Conclusion_Our finding may raise new evidence that genetically increased serum CRP level through SNPs variation is likely to induce family inherited depression.