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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 173-181页

作者： Zhi-yong LI wei-lin wu School of Electrical Engineering Zhejiang University Hangzhou 310027 China

Power Quality (PQ) combined disturbances become common along with ubiquity of voltage flickers and harmonics. This paper presents a novel approach to classify the different patterns of PQ combined disturbances. The classification system consists of two parts, namely the feature extraction and the automatic recognition. In the feature extraction stage, Phase Space Reconstruction (PSR), a time series analysis tool, is utilized to construct disturbance signal trajectories. For these trajectories, several indices are proposed to form the feature vectors. Support Vector Machines (SVMs) are then implemented to recognize the different patterns and to evaluate the efficiencies. The types of disturbances discussed include a combination of short-term dis-turbances (voltage sags, swells) and long-term disturbances (flickers, harmonics), as well as their homologous single ones. The feasibilities of the proposed approach are verified by simulation with thousands of PQ events. Comparison studies based on Wavelet Transform (WT) and Artificial Neural Network (ANN) are also reported to show its advantages.

关键词： Power Quality (PQ) Combined disturbance Classification Phase Space Reconstruction (PSR) Support Vector Machines (SVMs)

EFFECT OF DISCHARGE RATIO ON FLOW CHARACTERISTICS IN 90°EQUAL-WIDTH OPEN-CHANNEL JUNCTION

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Journal of Hydrodynamics 2009年第4期21卷 541-549页

作者： ZHANG Ting XU wei-lin wu Chao College of Civil Engineering Fuzhou University Fuzhou 350108 China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

For the 90° equal-width open-channel junction flow, the Reynolds averaged Navier-Stokes equations are solved while using the 3-D κ- ω model. The mean flow pattern and the secondary current are obtained. The model is validated by experimental data, and then applied to investigate the effect of the discharge ratio on the shape of separation zone shape, the cross-sectional mean flow angle and the contraction coefficient. The results are fairly close to those of the prior studies. The numerical modeling is both less time-consuming and less expensive to obtain the various flow parameters needed for engineering design.

关键词： κ- ω turbulent model open-channel junction separation zone secondary current

Numerical analysis of factors affecting the range of heat transfer in earth surrounding three subways

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Journal of China University of Mining and Technology 2008年第1期18卷 67-71页

作者： HU Zeng-hui LI Xiao-zhao ZHAO Xiao-bao XIAO lin wu wei Department of Earth Sciences Nanjing University Nanjing Jiangsu 210093 China

In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.

关键词： earth surrounding subways range of heat transfer factors affecting heat transfer numerical analysis

Dynamical changing patterns of histological structure and ultrastructure of liver graft undergoing warm ischemia injury from non-heart-beating donor in rats

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World Journal of Gastroenterology 2006年第30期12卷 4902-4905页

作者： Yi Ma Guo-Dong Wang lin-wei wu Rui-De Hu Organ Transplantation Center the First Affiliated Hospital Sun Yat-Sen UniversityGuangzhou 510080 Guangdong Province China Department of Pathology Sun Yat-Sen UniversityGuangzhou 510080 Guangdong Province China

AIM： To investigate the histological and ultra-structural characteristics of liver graft during different of warm ischemia time （WIT） in rats and to predict the maximum limitation of liver graft to warm ischemia. METHODS： The rats were randomized into 7 groups undergoing warm ischemia injury for 0, 10, 15, 20, 30, 45 and 60 min, respectively. All specimens having undergone warm ischemia injury were investigated dynamically by light and electron microscopy, and histochemistry staining. After orthotopic liver transplantation （OLT）, the recovery of morphology of liver grafts after 6, 24 and 48 h was observed. RESULTS： The donor liver from non-heart-beating donors （NHBD） underwent ischemia injury both in the warm ischemia period and in the reperfusion period. Morphological changes were positively related to warm ischemia injury in a time-dependent manner during the reperfusion period. The results demonstrated that different degrees of histocyte degeneration were observed when WIT was within 30 min, and became more severe with the prolongation of WIT, no obvious hepatocyte necrosis was noted in any specimen. In the group undergoing warm ischemia injury for 45 min, small focal necrosis occurred in the central area of hepatic Iobule first. In the group undergoing warm ischemia injury for 60 rain, patchy or diffused necrosis was observed and the area was gradually extended, while hepatic sinusoid endothelial cells were obviously swollen. Hepatic sinusoid was obstructed and microcirculation was in disorder.CONCLUSION： The rat liver graft undergoing warm ischemia injury is in the reversible stage when the WIT is within 30 min. The 45 min WIT may be a critical point of rat liver graft to endure warm ischemia injury. When the WIT is over 60 min, the damage is irreversible.

关键词： Liver transplantation Warm ischemia injury Morphological observation

Steroid elimination within 24 hours after orthotopic liver transplantation:effectiveness and tolerability

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Hepatobiliary & Pancreatic Diseases International 2012年第2期11卷 137-142页

作者： lin-wei wu,Zhi-Yong Guo,Qiang Tai,wei-Qiang Ju,Dong-Ping Wang,An-Bin Hu,Xiao-Feng Zhu and Xiao-Shun He Organ Transplantation Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China Organ Transplantation Center First Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 China Guangzhou China

BACKGROUND:Steroids have been the mainstay of immunosuppressive regimen in liver ***,the use of steroids is associated with various post-transplant *** study evaluated the efficacy and safety of reduced immunosuppressive regimen with steroids(steroid elimination within 24 hours post-transplant) in a cohort of Chinese liver transplant ***:Seventy-six patients in line with the selection criteria were enrolled in this prospective *** patients received anti-IL-2 receptor antibody induction and tacrolimusbased maintenance *** recipients were divided into two groups according to the duration of steroid use:40 transplant in a 3-month withdrawal group and the remaining 36 in a 24-hour elimination *** survival,postoperative infections,biopsy-proven acute rejection and steroidresistant acute rejection,non-healing wound,recurrence of hepatitis B virus(HBV) and hepatocellular carcinoma(HCC),de novo diabetes,hyperlipidemia and hypertension were assessed in the two ***:There was no significant difference in patient survival,incidence of acute rejection episodes and hyperlipidemia,and recurrence of HBV and HCC between the two ***,the incidence rates of post-transplant infection,non-healing wound,de novo diabetes and hypertension were significantly lower in the 24-hour elimination group than in the 3-month withdrawal group(all P values <0.05).CONCLUSION:Under anti-IL-2 receptor antibody induction and tacrolimus-based maintainance,steroid elimination within 24 hours post-transplant is associated with reduced steroidrelated complications without increasing the risk of rejection.

关键词： liver transplantation immunosuppression steroid side effects

Diagnosis of parathyroid tumor using Color Doppler ultrasound

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International English Education Research 2014年第2期 74-77页

作者： Qiuling Shi Haibo Fan Qi lin Zhanghong wei Ying wu Second Affiliated Hospital of Jinan University (Shenzhen People's Hospital) Shenzhen Guangdong China

What the liver organized examining to the diagnosis of liver disease, course of disease alive is appraised and treated and taught fruits by stages, judge respects such as the prognosis, etc. play an important role. In recent years, supersound lead down, examine marksmanship walk liver puncture the technology that examines living to employ at clinic extensively becoming while being living. In order to appraise its application effect, specially carry on reviewing summary analysis.

关键词： Color Doppler ultrasound Diagnosis Tumour

Liver transplantation using organs from deceased organ donors: a single organ transplant center experience

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Hepatobiliary & Pancreatic Diseases International 2014年第4期13卷 409-415页

作者： Ming Han Zhi-Yong Guo Qiang Zhao Xiao-Ping Wang Xiao-Peng Yuan Xing-Yuan Jiao Chun-Hua Yang Dong-Ping Wang wei-Qiang Ju lin-wei wu An-Bin Hu Qiang Tai Yi Ma Xiao-Feng Zhu Xiao-Shun He Organ Transplant Center First Affiliated HospitalSun Yat-Sen University

BACKGROUND： In 2011, a pilot program for deceased organ donation was initiated in China. We describe the first successful series of liver transplants in the pilot ***： From July 2011 to August 2012, our center performed 26 liver transplants from a pool of 29 deceased donors. All organ donation and allograft procurement were conducted according to the national protocol. The clinical data of donors and recipients were collected and summarized ***： Among the 29 donors, 24 were China Category II donors（organ donation after cardiac death）, and five were China Category III donors（organ donation after brain death followed by cardiac death）. The recipients were mainly the patients with hepatocellular carcinoma. The one-year patient survival rate was 80.8% with a median follow-up of 422（2-696） days. Among the five mortalities during the follow-up,three died of tumor recurrence. In terms of post-transplant complications, 9 recipients（34.6%） experienced early allograft dysfunction, 1（3.8%） had non-anastomotic biliary stricture,and 1（3.8%） was complicated with hepatic arterial *** of these complications resulted in patient death. Notably,primary non-function was not observed in any of the ***： With careful donor selection, liver transplant from deceased donors can be performed safely and plays acritical role in overcoming the extreme organ shortage in China.

关键词： liver transplantation organ donors tissue and organ procurement

Influence of warm ischemia injury on hepatic functional status and survival of liver graft in rats

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Hepatobiliary & Pancreatic Diseases International 2003年第4期2卷 504-508页

作者： Xiao-Shun He Yi Ma lin-wei wu wei-Qiang Ju Gui-Hua Chen Rui-De Hu Jie-Fu Huang the Organ Transplantation Center, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China Organ Transplantation Center First Affiliated Hospital of Sun Yat-Sen University Guangzhou 510080 China. xshe@***

OBJECTIVES: To investigate the changing patterns of functional and histological status, observe the posttransplantation survival of liver graft under different warm ischemia time (WIT) in rats, and determine the maximum limitation of liver graft to warm ischemia. METHODS: According to WIT, the rats were randomized into 7 groups, with WIT of 0, 10, 15, 20, 30, 45, 60 minutes respectively. Serum concentrations of alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase were measured at 1, 2, 3 and 5 days after orthotopic liver transplantation respectively. Liver graft specimens were observed histopathologically at the same interval. The rats' survival in each subgroup was observed. RESULTS: In terms of graft survival, there was no significant difference between subgroups within 30-minute WIT. In the group with 30-minute WIT, the recipient rats' survival rate was 83.3% (10/12) at one week, 58.3% (7/12) at one month, and 50.0% (6/12) at 3 months. In the group with 45-minute WIT, the recipient rats' survival rate was 66.7% (8/12) at one week, 33.3% (4/12) at one month, and 8.3% (1/12) at 3 months, whereas only 8.3% (1/12) of the rats had one-week survival in the group with 60-minute WIT. CONCLUSIONS: These results indicate that rat liver graft could be safely subject to warm ischemia within 30 minutes. When WIT is prolonged to 45 minutes, the recipients long-term survival is severely insulted, and both function and histological structure of liver graft may develop irreversible damage when WIT is prolonged to 60 minutes.

关键词： liver transplantation warm ischemia injury survival

Analysis on Double-difference Earthquake Location and the Seismicity Pattern of the Yangjiang Earthquake Sequences

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Earthquake Research in China 2008年第1期22卷 73-81页

作者： Kang Ying Yang Xuan Huang Wenhui Chen Xing Chen Guimei lin wei wu Huadeng Earthquake Administration of Guangdong Province Guangzhou 510070China

The locations of about 400 earthquakes in Yangjiang, Guangdong Province are determined using the double, difference earthquake location algorithm （DDA）. The seismicity pattern becomes concentrated from discrete grids. The rupture characteristics of the Yangjiang earthquake sequence show a conjugated distribution in NW and NE directions. The major distribution trends NE and dips NE with an angle of 30^o and a length of 30km,and the minor distribution trends NW and dips SE with an angle of 30^o and a length of 20km. The focal depth is 5km - 15km. The distribution of the Enping earthquake sequence,which is not far from Yangjiang,is NW-trending. The relationship between hypocenter distribution and geological structure is discussed.

关键词： Double-difference earthquake location algorithm Location image Rupturecharacteristic Yangjiang earthquake sequences

非线性负载Norton等效模型的改进分析方法

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电子测量与仪器学报 2017年第8期31卷 1336-1341页

作者：南琳尉伍电子科技大学电子科学技术研究院成都611731

建立高精度、计算简单的等效模型,对电力系统中非线性负载谐波情况进行准确分析,一直是国内外研究人员的关注重点。而Norton等效电路模型具有表达式及参数简单易于计算的优点,使其在非线性负载等效模型分析中广泛应用。但现有Norton等... 详细信息

建立高精度、计算简单的等效模型,对电力系统中非线性负载谐波情况进行准确分析,一直是国内外研究人员的关注重点。而Norton等效电路模型具有表达式及参数简单易于计算的优点,使其在非线性负载等效模型分析中广泛应用。但现有Norton等效模型没有考虑非线性负载谐波电流与谐波电压间的相互影响,分析结果存在较大误差。因此,为了提高Norton等效模型的精度,需要对其进行适当的改进。在传统Norton等效模型的基础上,对非线性负载存在影响的谐波进行分类,将得到的附加电流谐波分别用受控源表示,提出含有受控源的Norton改进等效模型。最后通过采用两种模型对电力系统非线性负载实测电压和电流计算对比,发现在不同的电压条件下,传统Norton模型等效阻抗计算结果差异达到2个数量级,而含有受控源的改进Norton等效电路模型计算得到的等效阻抗大小变化不大,基本可以近似相等。可见,相较于传统不含受控源的Norton等效模型,提出的含有受控源的Norton等效模型的精度与稳定性显著提升。

关键词：非线性负载谐波电流 Norton等效模型等效受控源