Integrated Protection Unit Design for Power Networks

Zhan-feng Fan,Sheng-ming Ge,Z Q Bo,Lin Wang,Feng-quan Zhou,Xing Liu,Guo-bing Song 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.4

This paper presents an hardware design solution for integrated protection of distribution systems (Network Protection Unit) by combining transient polarity comparison technique, which is based on the detection and processing of fault generated transient current signals. The integrated protection relays installed at each substation of a distribution network are communicated with the Network Protection Unit through specially designed Packet Transport Network (PTN) for fast and reliable transmission of transient polarity current signals. The relay detects the faulted generated super-imposed current signals. The transient polarity identification algorithm is then applied to the super-imposed signals to identify the polarity of the signal detected. The Network Protection Unit can collect all the transient polarity current signals under its protection area. Then The direction of a fault is determined by comparison of the polarity of the signals derived from all the line sections connected to the substation. The actual faulted section is identified by the Network Protection Unit through comparing the directional information from various stations. Simulation results presented in the paper demonstrate the feasibility of the scheme.

A Study of Dynamic Forecast on Port Container Handling Capacity

Feng, Zhan-Qing,Lee, Su-Ho Korean Institute of Navigation and Port Research 2002 한국항해항만학회지 Vol.26 No.2

컨테이너 처리량(CHC)은 항만의 능력을 나타내는 중요한 지표다. 그러나 중국항만의 컨테이너 처리능력에 대한 연구는 부족하며, 연구결과 또한 예측치와 실제치와의 차이가 크다. 이는 컨테이너처리량이 다양한 경제적인 측면을 내포하고 있고 예측모델의 선택이 매우 어렵다는데 기인한다. 대체로 지금까지 사용되어왔던 회귀분석, 신경망분석 등은 과거행태모델을 벗어나지 못하고 있어 경제체제나 항만물동량의 동태적변화에 대한 고려가 결여되어 있다. 따라서 본 논문에서는 동태적 보정인과모델을 사용한 동태적 예측법을 사용해 보았고 그 결과 보다 신뢰성이 높고 현실성이 있는 연구결과를 도출할 수 있었다. In view of the great disparity between forecasts of Shanghai port container handling capacity and its real results, we choose a dynamic forecast method by the causality model dynamic compensation to predict Shanghai port container handling capacity. And we forecast Shanghai port container handling capacity by using this method. We have made a satisfactory achievement, which provides a more reliable and practical way to forecast container handling capacity.

New DTR Estimation Method Without Measured Solar and Wind Data

Zhan-Feng Ying,Yuan-Sheng Chen,Kai Feng 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.2

Dynamic thermal rating (DTR) of overhead transmission lines can provide a significant increase in transmission capacity compared to the static thermal rating. However, the DTR are usually estimated by the traditional thermal model of overhead conductor that is highly dependent on the solar, wind speed and wind direction data. Consequently, the estimated DTR would be unreliable and the safety of transmission lines would be reduced when the solar and wind sensors are out of function. To address this issue, this study proposed a novel thermal model of overhead conductor based on the thermal-electric analogy theory and Markov chain. Using this thermal model, the random variation of conductor temperature can be simulated with any specific current level and ambient temperature, even if the solar and wind sensors are out of function or uninstalled. On this basis, an estimation method was proposed to determine the DTR in the form of probability. The laboratory experiments prove that the proposed method can estimate the DTR reliably without measured solar and wind data.

논문(論文) : 신라(新羅)와 당(唐)의 교육체제(敎育體制) 비교 -중앙관학(中央官學)을 중심으로-

유점봉 ( Zhan Feng Liu ) 대구사학회 2011 대구사학 Vol.104 No.-

Shilla Education can be divided into the Hwarangdo(花郞道) Education and the Kookhak Education two stages in accordance with Before and after the unification. The Hwarangdo Education is a Special education form in Shilla, and a Important way of Personnel training and The official selection. But in Shilla`s reunification Historical back ground in Seventh century, The Hwarangdo Education was can not To meet the requirements of the times. In order to better training and selection of personnel, Shilla needed for a new education system in realy, so taked Guozijian(國子監, Imperial Academy) of Tang Dynasty for reference, set up native educational institutions-Kook-hak(국학, National School). Shilla`s kookhak was imitated the Tang Dynasty system In many aspect, such as Institutional settings, Official organization, Course arrangement and The students of management. The focus of The contents of Education was focus on Confucian classicsin(儒學經典) in Shilla`s National School, teaching material was derive from china, Selective absorption and used within the select key, not was completely copy In essence. According to the actual situation, Choose Five classics(五經), not Nine classics(九經) as Tang dynasty in the Choose of materials. And Shilla`s National School was attached importance to WenXuan(文選, Selections of Refined Literature). In order to select talents, Shilla`s National School has established the Dokseosampumgwa(讀書三品科), granted an official qualification to National students by way of examination. There was similarity with gwageo of china. But the fundamental nature of Dokseosampumgwa was not gwageo(科擧制) from the object of test, examination content and the test method. Therefore we can say the educational system of Shilla has imitated to China In general and surface, but still retained Shilla`s identity.

Brain Tumor Segmentation from Multispectral MRIs Using Sparse Representation Classification and Markov Random Field Regularization

Tianming Zhan,Shenghua Gu,Can Feng,Yongzhao Zhan,Jin Wang 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.9

Automatic brain tumor segmentation from multispectral magnetic resonance imaging (MRI) data is an important but a challenging task because of the high diversity in the appearance of tumor tissues among different patients and in many cases similarity with the normal tissues. In this paper, we propose a fully automatic technique for brain tumor segmentation from multispectral human brain MRIs. We first use the intensities of different patches in multispectral MRIs to represent the features of both normal and abnormal tissues and generate a dictionary for following tissue classification. Then, the sparse representation classification (SRC) is applied to classify the brain tumor and normal brain tissue in the whole image. At last, the Markov random field (MRF) regularization introduces spatial constraints to the SRC to take into account the pair-wise homogeneity in terms of classification labels and multispectral voxel intensities. Our method was evaluated on 20 multi-modality patient datasets with competitive segmentation results.

A Study of Dynamic Forecast on Port Container Handling Capacity

馮湛靑(Zhan-Qing Feng),이수호(Su-Ho Lee) 한국항해항만학회 2002 한국항해항만학회지 Vol.26 No.2

컨테이너 처리량(CHC)은 항만의 능력을 나타내는 중요한 지표다. 그러나 중국항만의 컨테이너 처리능력에 대한 연구는 부족하며, 연구결과 또한 예측치와 실제치와의 차이가 크다. 이는 컨테이너처리량이 다양한 경제적인 측면을 내포하고 있고 예측모델의 선택이 매우 어렵다는데 기인한다. 대체로 지금까지 사용되어왔던 회귀분석, 신경망분석 등은 과거행태모델을 벗어나지 못하고 있어 경제체제나 항만물동량의 동태적변화에 대한 고려가 결여되어 있다. 따라서 본 논문에서는 동태적 보정인과모델을 사용한 동태적 예측법을 사용해 보았고 그 결과 보다 신뢰성이 높고 현실성이 있는 연구결과를 도출할 수 있었다. In view of the great disparity between the previous forecasts of Shanghai port container handling capacity and its real results, we choose a dynamic forecast method by the causality model with dynamic compensation to predict Shanghai port container handling capacity. And we forecast Shanghai port container handling capacity by using this method. We have made a satisfactory achievement, which provides a more reliable and practical way to forecast container handling capacity.

New DTR Estimation Method Without Measured Solar and Wind Data

Ying, Zhan-Feng,Chen, Yuan-Sheng,Feng, Kai The Korean Institute of Electrical Engineers 2017 Journal of Electrical Engineering & Technology Vol.12 No.2

Dynamic thermal rating (DTR) of overhead transmission lines can provide a significant increase in transmission capacity compared to the static thermal rating. However, the DTR are usually estimated by the traditional thermal model of overhead conductor that is highly dependent on the solar, wind speed and wind direction data. Consequently, the estimated DTR would be unreliable and the safety of transmission lines would be reduced when the solar and wind sensors are out of function. To address this issue, this study proposed a novel thermal model of overhead conductor based on the thermal-electric analogy theory and Markov chain. Using this thermal model, the random variation of conductor temperature can be simulated with any specific current level and ambient temperature, even if the solar and wind sensors are out of function or uninstalled. On this basis, an estimation method was proposed to determine the DTR in the form of probability. The laboratory experiments prove that the proposed method can estimate the DTR reliably without measured solar and wind data.

NUMERICAL MODELING OF VERTICAL-2D UNSTEADY FLOW AND SUSPENDED MATERIAL DISTRIBUTION

ZHANG XIAO-FENG,FENG XIAO-XIANG,CUI ZHAN-FENG 한국수자원학회 2005 한국수자원학회 학술대회 Vol.2005 No.1

Ginsenoside Rg5 overcomes chemotherapeutic multidrug resistance mediated by ABCB1 transporter: in vitro and in vivo study

Feng, Sen-Ling,Luo, Hai-Bin,Cai, Liang,Zhang, Jie,Wang, Dan,Chen, Ying-Jiang,Zhan, Huan-Xing,Jiang, Zhi-Hong,Xie, Ying The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.2

Background: Multidrug resistance (MDR) to chemotherapy drugs remains a major challenge in clinical cancer treatment. Here we investigated whether and how ginsenoside Rg5 overcomes the MDR mediated by ABCB1 transporter in vitro and in vivo. Methods: Cytotoxicity and colon formation as well as the intracellular accumulation of ABCB1 substrates were carried out in MDR cancer cells A2780/T and A549/T for evaluating the reversal effects of Rg5. The expressions of ABCB1 and Nrf2/AKT pathway were determined by Western blotting. An A549/T cell xenograft model was established to investigate the MDR reversal activity of Rg5 in vivo. Results: Rg5 significantly reversed ABCB1-mediated MDR by increasing the intracellular accumulation of ABCB1 substrates without altering protein expression of ABCB1. Moreover, Rg5 activated ABCB1 ATPase and reduced verapamil-stimulated ATPase activity, suggesting a high affinity of Rg5 to ABCB1 binding site which was further demonstrated by molecular docking analysis. In addition, co-treatment of Rg5 and docetaxel (TXT) suppressed the expression of Nrf2 and phosphorylation of AKT, indicating that sensitizing effect of Rg5 associated with AKT/Nrf2 pathway. In nude mice bearing A549/T tumor, Rg5 and TXT treatment significantly suppressed the growth of drug-resistant tumors without increase in toxicity when compared to TXT given alone at same dose. Conclusion: Therefore, combination therapy of Rg5 and chemotherapy drugs is a strategy for the adjuvant chemotherapy, which encourages further pharmacokinetic and clinical studies.

Growth Inhibition and Apoptosis Induction of Human Umbilical Vein Endothelial Cells by Apogossypolone

Zhan, Yong-Hua,Huang, Xiao-Feng,Hu, Xing-Bin,An, Qun-Xing,Liu, Zhi-Xin,Zhang, Xian-Qing Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

Aims and Background: Prostate cancer is one of the most common malignant tumors in the male reproductive system, which causes the second most cancer deaths of males, and control of angiogenesis in prostate lesions is of obvious importance. This study assessed the effect of apogossypolone (ApoG2) on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs). Subjects and Methods: HUVECs were treated with different concentrations of ApoG2. The survival rate of HUVECs were determined by MTT assay. Utrastructural changes of HUVECs were assessed with transmission electron microscopy. Apoptosis in HUVECs was analyzed by flow cytometry and cell migration by Boyden chamber assay. Matrigel assays were used to quantify the development of tube-like networks. Results: ApoG2 significantly inhibited HUVEC growth even at 24 h (P<0.05). The inhibitory effect of ApoG2 is more obvious as the concentration and the culture time increased (P<0.05). These results indicate that ApoG2 inhibits the proliferation of HUVECs in a time- and concentration-dependent manner with increase of the apoptosis rate. Besides, ApoG2 reduced the formation of total pseudotubule length and network branches of HUVECs. Conclusions: The results suggest that ApoG2 inhibits angiogenesis of HUVECs by growth inhibition and apoptosis induction.