Seamless Transfer of Single-Phase Utility Interactive Inverters with a Synchronized Output Regulation Strategy

Xiang, Ji,Ji, Feifan,Nian, Heng,Zhang, Junming,Deng, Hongqiao The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.5

This study presents a strategy using the synchronized output regulation method (SOR) for controlling inverters operating in stand-alone and grid-connected modes. From the view point of networked dynamic systems, SOR involves nodes with outputs that are synchronized but also display a desirable wave shape. Under the SOR strategy, the inverter and grid are treated as two nodes that comprise a simple network. These two nodes work independently under the stand-alone mode. An intermediate mode, here is named the synchronization mode, is emphasized because the transition from the stand-alone mode to the grid-connected mode can be dealt as a standard SOR problem. In the grid-connected mode, the inverter operates in an independent way, in which the voltage reference changes for generalized synchronization where its output current satisfies the required power injection. Such a relatively independent design leads to a seamless transfer between operation modes. The closed-loop system is analyzed in the state space on the basis of the output regulation theory, which improves the robustness of the design. Simulations and experiments are performed to verify the proposed control strategy.

Seamless Transfer of Single-Phase Utility Interactive Inverters with a Synchronized Output Regulation Strategy

Ji Xiang,Feifan Ji,Heng Nian,Junming Zhang,Hongqiao Deng 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.5

This study presents a strategy using the synchronized output regulation method (SOR) for controlling inverters operating in stand-alone and grid-connected modes. From the view point of networked dynamic systems, SOR involves nodes with outputs that are synchronized but also display a desirable wave shape. Under the SOR strategy, the inverter and grid are treated as two nodes that comprise a simple network. These two nodes work independently under the stand-alone mode. An intermediate mode, here is named the synchronization mode, is emphasized because the transition from the stand-alone mode to the grid-connected mode can be dealt as a standard SOR problem. In the grid-connected mode, the inverter operates in an independent way, in which the voltage reference changes for generalized synchronization where its output current satisfies the required power injection. Such a relatively independent design leads to a seamless transfer between operation modes. The closed-loop system is analyzed in the state space on the basis of the output regulation theory, which improves the robustness of the design. Simulations and experiments are performed to verify the proposed control strategy.

Monoamine Oxidase Inhibitory Constituents from the Fruits of Cudrania tricuspidata

Xiang Hua Han,홍성수,Ji Sang Hwang,Seon Hwa Jeong,Ji Hye Hwang,Min Hee Lee,이명구,이동호,Jai Seup Ro,황방연 대한약학회 2005 Archives of Pharmacal Research Vol.28 No.12

A methylene chloride soluble fraction of the fruits of Cudrania tricuspidata significantly inhibited the mouse brain monoamine oxidase (MAO). Three known prenylated isoflavones were isolated and identified by activity-guided fractionation. Gancaonin A (1), 4'-O-methylalpinumisoflavone (2), and alpinumisoflavone (3) inhibited MAO activity in a concentration-dependent manner with IC50 values of 19.4, 23.9, and 25.8 µM, respectively. Of these, gancaonin A (1) showed a selective and potent inhibitory effect against MAO-B (IC50 0.8 µM) than MAO-A (IC50 >800 µM). The kinetic analysis using Lineweaver-Burk plots indicated that gancaonin A (1) competitively inhibited MAO-B.

Analysis of Germplasm in American Black Walnut by RAPD Markers

Xiang Shen,Zhi quan. Mao,Ji xiang. Zhang,Lei Wang,Jing Zhang 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

Variation of saponin contents in Korean Soybean Landraces

Ji-Seok Lee,Xiang-Min Piao,Hyo-Jae Lee,Yeong-Eun Yoo,Sun-Lim Kim,Hong-Sig Kim 한국육종학회 2012 한국육종학회 심포지엄 Vol.2012 No.07

This study investigated saponin contents according to collection area, seed size and seed color in 293 Korean soybean landraces. Results showed that total group A was 149.8 to 1279.0㎍/g with an average of 484.9㎍/g while total group B saponin content was 2160.1 to 7868㎍/g with an average of 3670㎍/g. Total groups A and B saponin content were ranging from 2502.7 to 8763.9㎍/g with an average of 4154.8㎍/g. The landraces with high group B saponin content were IT226841, IT226761, IT226844 and IT226826. The landraces with low group A saponin content were IT228580, IT228319, IT228308 and IT226841. According to collection areas, the highest amount of saponin content was observed in the landraces collected from North Korea. High total of saponin content was showed by seeds from Gyeonggi-do, followed by Chungcheongbuk-do, Gangwon-do, Gyongsangbuk-do, Chungcheongnam-do Jeollabuk-do and Jeollanam-do. According to seed size, small seeds have the higest saponin contentfollowed by the medium and large size of seeds. For seed color, there was no significant difference in saponin content. The total of saponin content was postively correlated with group A saponin, group B saponin and total of saponin cntent. Among each components, group A saponin showed postive correlations with total of saponin and group B saponin content.

Poster Session : Ni 함량변화와 W 첨가가 스테인리스강의 재부동태 특성에 미치는 영향 연구

Pan Ji Xiang,김진석,김규영 한국부식방식학회(구 한국부식학회) 2002 춘계 학술발표회 초록집 Vol.- No.-

Monoamine Oxidase Inhibitory Constituents from the Fruits of Cudrania tricuspidata

Han Xiang Hua,Hong Seong Su,Hwang Ji Sang,Jeong Seon Hwa,Hwang Ji Hye,Lee Min Hee,Lee Myung Koo,Lee Dongho,Ro Jai Seup,Hwang Bang Yeon The Pharmaceutical Society of Korea 2005 Archives of Pharmacal Research Vol.28 No.12

A methylene chloride soluble fraction of the fruits of Cudrania tricuspidata significantly inhibited the mouse brain monoamine oxidase (MAO). Three known prenylated isoflavones were isolated and identified by activity-guided fractionation. Gancaonin A (1), 4'-O-methylalpinumisoflavone (2), and alpinumisoflavone (3) inhibited MAO activity in a concentration-dependent manner with $IC_{50}$ values of 19.4, 23.9, and 25.8 $\mu$M, respectively. Of these, gancaonin A (1) showed a selective and potent inhibitory effect against MAO-B ($IC_{50}$ 0.8 $\mu$M) than MAO-A ($IC_{50}$ >800 $\mu$M). The kinetic analysis using Lineweaver-Burk plots indicated that gancaonin A (1) competitively inhibited MAO-B.

Suppressive Effect of Sinomenine Combined with 5-Fluorouracil on Colon Carcinoma Cell Growth

Zhang, Ji-Xiang,Yang, Zi-Rong,Wu, Dan-Dan,Song, Jia,Guo, Xu-Feng,Wang, Jing,Dong, Wei-Guo Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

It is reported that sinomenine (SIN) and 5-fluorouracil (5-FU) both are effective for colon cancer, but their cooperative suppressive effects and toxicity remain to be clarified in detail. This study aimed to determine suppressive effects and toxicity of sinomenine (SIN) plus 5-fluorouracil (5-FU) on LoVo colon carcinoma cells in vitro and in vivo. CCK-8, Hoechst 33258 staining and an annexin V-FITC/PI apoptosis kit were used to detect suppressive effects. Western blotting was applied to investigate the essential mechanism underlying SIN and 5-FU-induced apoptosis. SIN or 5-FU or both were injected into nude mice, and then suppressive effects and side effects were observed. SIN plus 5-FU apparently inhibited the proliferation of LoVo cells and induced apoptosis. Moreover the united effects were stronger than individually (p<0.05). The results of annexin V-FITC/PI staining and Hoechst 33258 staining showed that the percentage of apoptotic cells induced by SIN and 5-FU combined or alone was significantly higher than the control group (p<0.05). Expression of Bax and Bcl-2 was up-regulated and down-regulated respectively. SIN or 5-FU significantly inhibited effects on the volume of tumour xenografts and their combined suppressive effects were stronger (p<0.05). No obvious side effects were observed. It was apparent that the united effects of SIN and 5-FU on the growth of colorectal carcinoma LoVo cells in vitro and in vivo were superior to those using them individually, and it did not markedly increase the side effects of chemotherapy.

초기 북관개시(北關開市)와 야춘인(也春人)문제

주상길 ( Xiang Ji Zhu ),유희도 ( Xi Tao Liu ) 한국민족학회 2009 민족학연구 Vol.8 No.-

조선 후기 만주지역과 조선 간에 진행한 무역을 사행무역과 변시무역으로 구별할 수 있는데 이런 무역은 조공체제 하의 성격을 지니었다. 현재 사행무역에 대한 연구는 상당한 성과를 거두었으나 변시무역 특히 북관개시 중의 초기 회령개시 참가자인 야춘인과 경원개시가 열리게 된 원인에 대한 연구가 충분하게 진행되지 않았다. 본고는 선행 연구에 기초하여 중국과 한국의 사료를 접목시켜 호상 보충하는 방법으로써 초기 회령개시 청측 참가자 야춘인의 상황과 경원개시가 열리게 된 원인을 밝히고 나아가 선행 연구의 부족한 점도 보완하려고 한다. 1639년 청은 피역을 피해 웅도로 도망간 여진 와이객의 일부인 경하창 무리를 두 차례 정벌하여 그해 말에 이들을 야춘지역에 이주시키었다. 청은 이들 야춘인의 생활과 농경을 위하여 1642년 회령개시에 이들을 참가시켜 필요한 물화를 교역해 가게 하였다. 그 후 야춘지역의 일부 와이객이 혼춘지역에 이주하자 주변의 산재한 여진 종족들이 모여들어 인구가 급증하였다. 그리하여 혼춘지역과 야춘지역 와이객들의 생활과 농경을 위하여 청은 거리상 가까이에 있는 경원에서 개시할 것을 조선에 요청하였다. 경원개시가 열리게 되자 이들은 회령개시에 참가하지 않고 가까운 거리에 있는 경원개시에 참가하였다. 1654년에는 鴉客素河에서 新戶人들이 야춘지역에 이주해 왔고, 야춘지역에 남아있던 야춘인들과 함께 경원개시에 참가하였다. 그 후에 이들도 혼춘에로 이주하면서 경원개시에 참가하였다. 이는 초기 회령개시와 경원개시를 열게 된 원인과 『通文館志』事大上開市條에 나오는 개시에 참가한 야춘인들에 대한 해석이다. 또한 이 연구는 차후 두만강 이북과 이동 지역사의 연구와 조선인들의 간도에로의 이주에도 밑거름이 되는 작업이라고 생각된다. 이런 조선 후기의 변시무역은 1882년에 중단되고 근대식 자유통상방식으로 전환되었다. In the Qing Dynasty, the trade between Northeast China and Korea can be divided into two parts: ambassador trade and the frontier mutual trade. At that moment, the trade between the Qing Dynasty and Korea has the nature of the tributary system. Now the study of ambassador trade have achieve fairly good results, but the study of the frontier mutual trade between the Qing Dynasty and Korea is not full and detailed, especially (the study)of the initial period of the opening in the Beiguan market and its participants-the people of Yechun. In this paper, with the historical materials of China and Korea, the author uses the methods of complementary and textual research to reveal the process of trade among the participants of the initial period of the opening in the Beiguan market and the reason for opening the market in Qingyuan. Thereby, we can find out the development of Hunchun and its trade embryonic with Korea in the late Ming and early Qing dynasty, and then lay the foundation for the study of the frontier mutual trade between the Northeast China and Korea in the Qing Dynasty.

Monoamine Oxidase Inhibitory Components from Cayratia japonica

Xiang Hua Han,Jai Seup Ro,홍성수,Ji Sang Hwang,이명구,황방연 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.1

Seven flavonoids were isolated from the whole plants and fruits of Cayratia japonica through the activity-guided isolation of a methanol extract using a monoamine oxidase (MAO) inhibition assay as a monitor. The chemical structures of the isolates were assigned as apigenin-7- O-β-D-glucuronopyranoside (1), apigenin (2), luteolin (3), luteolin-7-O-β-D-glucopyranoside (4), (+)-dihydroquercetin (taxifolin) (5), (+)-dihydrokaempferol (aromadendrin) (6) and quercetin (7). Among the isolated compounds, flavones such as apigenin (2) and luteolin (3), as well as the flavonol, quercetin (7) showed potent inhibitory effects against the MAO activity with IC50 values of 6.5, 22.6, and 31.6 μM, respectively. However, the flavone glycosides, apigenin-7-O-β- D-glucuronopyranoside (1) and luteolin-7-O-β-D-glucopyranoside (4), showed mild MAO inhibition (IC50 values: 81.7 and 118.6 μM, respectively). The flavanonol derivatives, taxifolin (5) and aromadendrin (6), also showed weak inhibition (IC50 values: 154.7 and 153.1 μM, respectively). Furthermore, quercetin (7) had a more potent inhibitory effect on MAO-A (IC50 value: 2.8 μM) than MAO-B (IC50 value: 90.0 μM). Apigenin (2) and luteolin (3) also preferentially inhibited MAO-A (IC50 values: 1.7 and 4.9 μM, respectively) compared with MAO-B (IC50 values: 12.8 and 59.7 μM, respectively).