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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)

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

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

Chronic stress as an emerging risk factor for the development and progression of glioma

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Chinese Medical Journal 2024年第4期137卷 394-407页

作者： Lan Yi Xiang lin Xiaoling She wei Gao Minghua wu Institute of Cytology and Genetics The Hengyang Key Laboratory of Cellular Stress BiologyHunan Province Cooperative Innovation Center for Molecular Target New Drug StudyHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Pathology The Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education Cancer Research InstituteCentral South UniversityChangshaHunan 410008China NHC Key Laboratory of Carcinogenesis Xiangya HospitalCentral South UniversityChangshaHunan 410008China

Gliomas tend to have a poor prognosis and are the most common primary malignant tumors of the central nervous *** with patients with other cancers,glioma patients often suffer from increased levels of psychological stress,such as anxiety and *** stress(CS)is thought to impact glioma ***,because of the complex mechanisms underlying CS and variability in individual tolerance,the role of CS in glioma remains *** review suggests a new proposal to redivide the stress system into two *** activity is dominant ***-signaling molecules produced by the neuroendocrine system are dominant *** discuss the underlying molecular mechanisms by which CS impacts *** pharmacological treatments are also summarized from the therapeutic perspective of CS.

关键词： Chronic stress Glioma Microbiota-gut-brain axis Neuroendocrine system Stress system Neural circuit

Adhesion strength of tetrahydrofuran hydrates is dictated by substrate stiffness

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Petroleum Science 2024年第1期21卷 667-673页

作者： Yan-Wen lin Tong Li Yi Zhang wei-wei Yan Xiao-Ming Chen Zhi-Sen Zhang Jian-Yang wu Department of Physics Research Institute for Biomimetics and Soft MatterJiujiang Research Institute and Fujian Provincial Key Laboratory for Soft Functional Materials ResearchXiamen UniversityXiamen361005FujianChina Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201ZhejiangChina Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyang621000SichuanChina Micro-and Nano-technology Research Center State Key Laboratory for Manufacturing Systems EngineeringXi’an Jiaotong UniversityXi’an710049ShaanxiChina Electronic Materials Research Lab Key Laboratory of the Ministry of EducationXi’an Jiaotong UniversityXi’an710049ShaanxiChina NTNU Nanomechanical Lab Norwegian University of Science and Technology(NTNU)Trondheim7491Norway

Understanding the hydrate adhesion is important to tackling hydrate accretion in ***,the relationship between the Tetrahydrofuran(THF)hydrate adhesion strength(AS)and surface stiffness on elastic coatings is systemically examined by experimental shear force measurements and theoretical *** mechanical factor-elastic modulus of the coatings greatly dictates the hydrate AS,which is explained by the adhesion mechanics theory,beyond the usual factors such as wettability and structural ***,the hydrate AS increases with reducing the thickness of the elastic coatings,resulted from the decrease of the apparent surface elastic *** effect of critical thickness for the elastic materials with variable elastic modulus on the hydrate AS is also *** study provides deep perspectives on the regulation of the hydrate AS by the elastic modulus of elastic materials,which is of significance to design anti-hydrate surfaces for mitigation of hydrate accretion in petro-pipelines.

关键词： Hydrate Adhesion strength Elastic modulus Coatings

A low-profile dual-broadband dual-circularly-polarized reflectarray for K-/Ka-band space applications

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Frontiers of Information Technology & Electronic Engineering 2024年第8期25卷 1145-1161页

作者： Xuanfeng TONG Zhi Hao JIANG Yuan LI Fan wu lin PENG Taiwei YUE wei HONG State Key Laboratory of Milimeter Waves School of Information Science and EngineeringSoutheast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 21lllChina State Key Laboratory of Mobile Network and Mobile Multimedia Technology ZTE CorporationShenzhen 518057China Apple Inc. One Apple Park WayCupertinoCA 95014USA

A low-profile dual-broadband dual-circularly-polarized(dual-CP)reflectarray(RA)is proposed and demonstrated,supporting independent beamforming for right-/left-handed CP waves at both K-band and *** functionality is achieved by incorporating multi-layered phase shifting elements individually operating in the K-and Ka-band,which are then interleaved in a shared aperture,resulting in a cell thickness of only about *** rotating the designed K-and Ka-band elements around their own geometrical centers,the dual-CP waves in each band can be modulated *** reduce the overall profile,planar K-/Ka-band dual-CP feeds with a broad band are designed based on the magnetoelectric dipoles and multi-branch hybrid *** planar feeds achieve bandwidths of about 32%and 26%at K-and Ka-band respectively with reflection magnitudes below-13 dB,an axial ratio smaller than 2 dB,and a gain variation of less than 1 dB.A proof-of-concept dual-band dual-CP RA integrated with the planar feeds is fabricated and characterized which is capable of generating asymmetrically distributed dual-band dual-CP *** measured peak gain values of the beams are around 24.3 and 27.3 dBic,with joint gain variation<1 dB and axial ratio<2 dB bandwidths wider than 20.6%and 14.6%at the lower and higher bands,*** demonstrated dual-broadband dual-CP RA with four degrees of freedom of beamforming could be a promising candidate for space and satellite communications.

关键词： Broadband Dual-band Dual-circularly-polarized Reflectarray Shared-aperture

Janus Quasi‑Solid Electrolyte Membranes with Asymmetric Porous Structure for High‑Performance Lithium‑Metal Batteries

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Nano-Micro Letters 2024年第6期16卷 221-232页

作者： Zerui Chen wei Zhao Qian Liu Yifei Xu Qinghe Wang Jinmin lin Hao Bin wu Institute for Composites Science Innovation(InCSI)and State Key Laboratory of Silicon and Advanced Semiconductor Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China

Quasi-solid electrolytes(QSEs)based on nanoporous materials are promising candidates to construct high-performance Limetal batteries(LMBs).However,simultaneously boosting the ionic conductivity(σ)and lithium-ion transference number(t^(+)) of liquid electrolyte confined in porous matrix remains ***,we report a novel Janus MOFLi/MSLi QSEs with asymmetric porous structure to inherit the benefits of both mesoporous and microporous *** Janus QSE composed of mesoporous silica and microporous MOF exhibits a neat Li^(+) conductivity of 1.5.10^(–4)S cm^(−1) with t^(+) of 0.71.A partially de-solvated structure and preference distribution of Li^(+)near the Lewis base O atoms were depicted by MD ***,the nanoporous structure enabled efficient ion flux regulation,promoting the homogenous deposition of Li^(+).When incorporated in Li||Cu cells,the MOFLi/MSLi QSEs demonstrated a high Coulombic efficiency of 98.1%,surpassing that of liquid electrolytes(96.3%).Additionally,NCM 622||Li batteries equipped with MOFLi/MSLi QSEs exhibited promising rate performance and could operate stably for over 200 cycles at 1 *** results highlight the potential of Janus MOFLi/MSLi QSEs as promising candidates for next-generation LMBs.

关键词： Metal-organic frameworks Mesoporous silicas Quasi-solid electrolytes Janus structure Lithium-metal battery

Prediction of solar activities:Sunspot numbers and solar magnetic synoptic maps

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Science China Earth Sciences 2024年第8期67卷 2460-2477页

作者： Rui ZHUO Jiansen HE Die DUAN Rong lin Ziqi wu Limei YAN Yong wei School of Earth and Space Sciences Peking UniversityBeijing 100091China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Centre for Mathematical Plasma Astrophysics Department of MathematicsKU LeuvenLeuven 3001Belgium Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The evolution of solar magnetic fields is significant for understanding and predicting solar *** our knowledge of solar magnetic fields largely depends on the photospheric magnetic *** this paper,based on the spherical harmonic expansion of the photospheric magnetic field observed by Wilcox Solar Observatory,we analyze the time series of spherical harmonic coefficients and predict Sunspot Number as well as synoptic maps for Solar Cycle *** find that solar maximum years have complex short-period disturbances,and the time series of coefficient g_(7)~0 is nearly in-phase with Sunspot Number,which may be related to solar meridional *** Long Short-Term Memory networks(LSTM),our prediction suggests that the maximum of Solar Cycle 25 is likely to occur in June 2024 with an error of 8 months,the peak sunspot number may be 166.9±22.6,and the next solar minimum may occur around January *** incorporating Empirical Mode Decomposition,we enhance our forecast of synoptic maps truncated to Order 5,validating their relative *** prediction not only addresses a gap in forecasting the global distribution of the solar magnetic field but also holds potential reference value for forthcoming solar observation plans.

关键词： Solar activity prediction Solar magnetic field Spherical harmonic expansion Long-Short Term Memory(LSTM) Empirical Mode Decomposition(EMD)

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Graft-verse-host disease after liver transplantation:A report of two cases and review of literature

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World Journal of Gastroenterology 2008年第6期14卷 974-979页

作者： Zhi-Yong Guo Xiao-Shun He lin-wei wu Xiao-Feng Zhu wei-Qiang Ju Dong-Ping Wang Shen You Yi Ha Guo-Dong Wang Jie-Fu Huang Organ Transplantation center First Affiliated Hospital Sun Yat-Scn University Guangzhou 510080 Guangdong Province China

Graft-verse-host disease (GVHD) is an uncommon fatal complication following liver transplantation (LTx). In China's Mainland, only six cases have been reported with a morbidity rate up to 1%-2%. Definitive diagnosis was achieved by molecular techniques (HLA typing or PCR-STR) in only two cases and the remaining cases were diagnosed based on typical clinical features with exclusion of other possible causes. All patients died of septic shock or multiple organ failure even after administration of increased corticosteroids and supportive therapy, and reduced immunosuppressive agents. In our center, two cases of GVHD were found among 128 (1.56%) patients. One case was diagnosed by detecting lymphocyte macrochimerism through DNA-STR. Both of them died even after aggressive treatment. In China, the incidence of GVHD is similar to that reported by foreign centers except for an extremely bad prognosis. Rapid diagnosis is crucial for a better prognosis. In China, only 37.5% of cases are diagnosed by molecular methods. We recommend detecting lymphocyte macrochimerism through DNA-STR to get a rapid diagnosis, and interleukin 2-receptor antibody (basiliximab or daclizumab) therapy seems to be a good choice for the disease.

关键词： Graft-versus-host disease Liver transplantation Prognosis Diagnosis Treatment