检索结果-南通市图书馆

Interharmonic Analysis Model of Photovoltaic Grid-connected System with Extended Dynamic Phasors

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1540-1547页

作者： Qing Zhong Yangxin qiu Yuming Zhao Haifeng Li gang Wang Fushuan Wen School of Electric Power South China University of Technology Shenzhen Power Supply Bureau Co. Ltd. School of Electrical Engineering Zhejiang University

The interactions between randomly fluctuating power outputs from photovoltaic(PV) at the DC side and background voltage distortions at the AC side could generate interharmonics in the PV grid-connected system(PVGS). There is no universal method that can reveal the transmission mechanism of interharmonics and realize accurate calculation in different scenarios where interharmonics exist in the PVGS. Therefore, extended dynamic phasors(EDPs) and EDP sequence components(EDPSCs) are employed in the interharmonic analysis of the PVGS. First, the dynamic phasors(DPs) and dynamic phasor sequence components(DPSCs) are extended into EDPs and EDPSCs by selecting a suitable fundamental frequency other than the power frequency. Second, an interharmonic analysis model of the PVGS is formulated as a set of state space equations. Third, with the decoupling characteristics of EDPSCs,generation principles and interactions among the interharmonics in the PVGS are presented by the sequence components,and its correctness is verified by simulation and *** presented model can be used to accurately calculate the interharmonics generated in the PVGS both at the AC and DC sides. Because of the decoupling among the EDPSCs, the set of state space equations can effectively describe the principle.

关键词： Dynamic phasor sequence component(DPSC) harmonic interharmonic photovoltaic grid-connected system(PVGS) power quality

Radiofrequency Ablation of Hepatic Paragonimiasis: a Case Report

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Sciences Journal 2012年第1期27卷 57-59页

作者： Wei-gang Cao Bao-an qiu Department of Hepatobiliary Surgery PLA Navy General HospitalBeijing 100048China

HEPATIC paragonimiasis is a rare disease with non-specific manifestation, which is often misdiagnosed in clinical practice. Long-time drug therapy treating this disease would be accompanied by the possible development... 详细信息

关键词： radiofrequency ablation paragonimiasis liver

Coagulation indices and fibrinogen degradation products as predictive biomarkers for tumor-node-metastasis staging and metastasis in gastric cancer

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2025年第1期17卷 110-120页

作者： yi-Qing Shen qiu-Wan Wei yi-Ren Tian Yun-Zhi Ling Min Zhang Clinical Laboratory Civil Aviation Shanghai HospitalGubei Branch of Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200000China Clinical Laboratory Tongji Hospital of Tongji UniversityShanghai 200000China

BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and *** with the global average,Asia,notably China,reports disproportionately high GC *** disease often progresses asymptoma-tically in the early stages,leading to delayed diagnosis and compromised ***,it is crucial to identify early diagnostic biomarkers and enhance treatment strategies to improve patient outcomes and reduce *** Retrospectively analyzed the clinical data of 148 patients with GC treated at the Civil Aviation Shanghai Hospital between December 2022 and December *** associations of coagulation indices-partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT),fibrinogen,fibrinogen degradation products(FDP),fasting blood glucose,and D-dimer(D-D)with TNM stage and distant metastasis were *** Prolongation of APTT,PT,and TT was significantly correlated with the GC TNM ***,abnormal coagulation system activation was closely related to disease *** FDP and D-D were significantly associated with distant metastasis in GC(P<0.05),suggesting that increased fibrinolytic activity contributes to increased metastatic *** Our Results reveal coagulation indices,FDPs as GC biomarkers,reflecting abnormal coagulation/fibrinolysis,aiding disease progression,metastasis prediction,and helping clinicians assess thrombotic risk for early intervention and personalized treatment plans.

关键词： Coagulation indexes Fibrinogen degradation products Gastric cancer Tumor-node-metastasis staging Distant metastasis

Symmetry restoring dynamics in a two-species bosonic Josephson junction by using occasional coupling

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2020年第5期72卷 113-119页

作者： Jing Tian yi-Fan Wang Hai-Bo qiu School of Science Xi'an University of Posts and Telecommunications710121 Xi'anChina

In this paper,by employing an occasionally coupling scheme in a two-species bosonic Josephson junction,it is found that for nonlocal measure synchronized states appearing in the two dynamic modes,known as 0-phase mode andπphase mode,their broken-symmetry can be ***,there are dramatic differences for the *** 0-phase mode,we can restore the broken symmetry by turning the nonlocal MS state into a conventional quasiperiodic MS ***,for theπ-phase mode,the broken symmetry is restored accompanied by the appearance of chaotic MS states.

关键词： symmetry restoring nonlocal measure synchronization bosonic Josephson junction

Synthesis and application of bilayer-surfactant-enveloped Fe_3O_4 nanoparticles: water-based bilayer-surfactant-enveloped ferrofluids

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 234-240页

作者： Bai-yi Chen Jian-hui qiu Hui-xia Feng Department of Machine Intelligence and Systems Engineering Faculty of Systems Engineering Akita Prefectural University College of Petrochemical Technology Lanzhou University of Technology

Superparamagnetic carbon-coated Fe3O4 nanoparticles with high magnetization（85 emu·g-（-1）） and high crystallinity were synthesized using polyethylene glycol-4000（PEG（4000）） as a carbon ***3O4 water-based bilayer-surfactant-enveloped ferrofluids were subsequently prepared using sodium oleate and PEG（4000） as *** using X-ray photoelectron spectroscopy,X-ray diffraction,and Fourier-transform infrared spectroscopy indicate that the Fe3O4 nanoparticles with a bilayer surfactant coating retain the inverse spinel-type structure and are successfully coated with sodium oleate and PEG（4000）.Transmission electron microscopy,vibrating sample magnetometry,and particle-size analysis results indicate that the coated Fe3O4 nanoparticles also retain the good saturation magnetization of Fe3O4（79.6 emu·g^-1） and that the particle size of the bilayer-surfactant-enveloped Fe3O4 nanoparticles is 42.97 nm,which is substantially smaller than that of the unmodified Fe3O4 nanoparticles（486.2 nm）.UV-vis and zeta-potential analyses reveal that the ferrofluids does not agglomerate for 120 h at a concentration of 4 g·L^-1,which indicates that the ferrofluids are highly stable.

关键词： magnetic fluids iron oxides nanoparticles bilayers sodium oleate polyethylene glycol

Self assembled electron blocking and lithiophilic interface towards dendrite-free solid-state lithium battery

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 220-225页

作者： Caixia Li yi qiu Yufeng Zhao Wuliang Feng Institute for Sustainable Energy&College of Sciences Shanghai UniversityShanghai 200444China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

The poor interfacial contact is one of the biggest challenges that solid-state lithium batteries suffer *** the solid-state electrolyte surface energy by transforming the interface from lithiophobic to lithiophilic is effective to promote the interfacial contact, but electronic conductive interphases usually increase the risk of electron attack, thus leading to uncontrollable Li dendrite growth. Herein, we propose a self-assembled thermodynamic stable Li I interphase to simultaneously improve the interfacial contact between the garnet electrolyte Li_7La_(3)Zr_(2)O_(12)(LLZO) and Li anode, and prohibit the electron attack. The direct contact between LLZO and Li and the high temperature Li melting process was ascribed to Zr4+reduction, which facilitated Li dendrite formation and propagation. With the modification of the high lithiophilic I_(2) thin film, the area specific interfacial resistance of LLZO/Li was reduced from 1525 Ω/cm^(2) to 57 Ω/cm^(2). More importantly, LLZO was protected from being reduced due to the outstanding electronic insulativity of the Li I interphase, which leaded to a high critical current density of 1.2/7.0 m A/cm^(2) in the time/capacity-constant modes, respectively.

关键词： Li_7La_(3)Zr_(2)O_(12) LiI interphase Interfacial contact Li dendrite Thermodynamic stable

The total flow control equations and the characteristics of unsteady gradually varied flow in open channels

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2019年第1期31卷 177-185页

作者： Shi-he Liu Qian-yi Zhao qiu-shi Luo State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Yellow River Engineering Consulting Co. LtdZhengzhou 450003China

Most unsteady channel flows in nature and practical engineering appear as gradually varied ones,and in the free surface,the deformation conforms to the long wave ***-dimensional total flow models were usually used to for the numerical simulation of long-term and long-distance reaches to describe the water movements,however,the models lack a clear relationship between the three-dimensional flow field and the total flow ***,few studies of the variations of the roughness coefficient against the time in unsteady flows were *** following results are obtained through the theoretical analysis and the numerical simulations in this paper.(1) One-dimensional total flow control equations of the unsteady gradually varied flow in open channels are obtained directly from the mathematical model of the viscous fluid motion,and can both reflect the influence of the turbulence and provide an explicit expression of the energy slope *** equations establish a direct connection between the descriptions of the three-dimensional flow fields and the one-dimensional total flows.(2) Synchronous prototype observation data and planar two-dimensional numerical simulation results are used to extract the one-dimensional total flow information and discuss the total flow characteristics.(3)The orders of magnitude for terms in the total flow motion equation are compared,and the variation of the roughness coefficient against the time is analyzed.

关键词： Open channel unsteady flow total flow characteristics control equations

General properties of the spectral form factor in open quantum systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第3期19卷 229-237页

作者： yi-Neng Zhou Tian-gang Zhou Pengfei Zhang Institute for Advanced Study Tsinghua UniversityBeijing 100084China Department of Physics Fudan UniversityShanghai 200438China

The spectral form factor(SFF)can probe the eigenvalue statistic at different energy scales as its time variable *** closed quantum chaotic systems,the SFF exhibits a universal dip-ramp-plateau behavior,which reflects the spectrum rigidity of the *** this work,we explore the general properties of SFF in open quantum *** find that in open systems the SFF first decays exponentially,followed by a linear increase at some intermediate time scale,and finally decreases to a saturated plateau *** derive general relations between(i)the early-time decay exponent and Lindblad operators;(ii)the long-time plateau value and the number of steady *** also explain the effective field theory perspective of general *** verify our theoretical predictions by numerically simulating the Sachdev−Ye−Kitaev(SYK)model,random matrix theory(RMT),and the Bose−Hubbard model.

关键词： spectral form factor open quantum system quantum chaos

Robust H_∞ static output feedback control of discrete-time switched polytopic linear systems with average dwell-time

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science in China(Series F) 2009年第11期52卷 2019-2031页

作者： qiu JianBin FENG gang YANG Jie Space Control and Inertial Technology Research Center Harbin Institute of Technology Harbin 150001 China Department of Manufacturing Engineering and Engineering Management City University of Hong Kong Kowloon Hong Kong Department of Precision Machinery and Instrumentation University of Science and Technology of China Hefei 230026 China

This paper investigates the problem of robust exponential H∞ static output feedback controller design for a class of discrete-time switched linear systems with polytopic-type time-varying parametric uncertainties. The objective is to design a switched static output feedback controller guaranteeing the exponential stability of the resulting closed-loop system with a minimized exponential H∞ performance under average dwell-time switching scheme. Based on a parameter-dependent discontinuous switched Lyapunov function combined with Finsler＇s lemma and Dualization lemma, some novel conditions for exponential H∞ performance analysis are first proposed and in turn the static output feedback controller designs are developed. It is shown that the controller gains can be obtained by solving a set of linear matrix inequalities （LMIs）, which are numerically efficient with commercially available software. Finally, a simulation example is provided to illustrate the effectiveness of the proposed approaches.

关键词： static output feedback switched systems average dwell-time time-varying uncertainty H∞ control linear matrix inequality