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Modeling,Parameter Measurement,and Control of PMSG-based Grid-connected Wind Energy Conversion System

Journal of Modern Power Systems and Clean Energy 2021年第5期9卷 1054-1065页

作者： Mohammad Kamruzzaman Khan Prince Graduate Mohammad tArif Ameen Gargoom Aman MtOo Md Enamul Haque Renewable Energy&Electric Vehicle(REEV)Lab Centre for Smart Power&Energy Research(cSPER)School of EngineeringDeakin UniversityWaurn pondsAustralia

the design of reliable controllers for wind energy conversion systems(WECSs)requires a dynamic model and accurate parameters of the wind *** this paper,a dynamic model and the parameter measurement and control of a direct-drive variable-speed WECS with a permanent magnet synchronous generator(PMSG)are *** experimental method is developed for measuring the key parameters of the *** measured parameters are used in the design of the *** generator-side converter is controlled using a vector control scheme that maximizes the power extraction under varying wind speeds.A model predictive controller(MPC)is designed for the grid-side voltage source converter(VSC)to regulate the active and reactive power flows to the power grid by controlling the d-and q-axis currents in the synchronous reference *** MPC predicts the future values of the control variables and takes control actions based on the minimum value of the cost *** comply with the grid code requirement,a modified design approach for an LCL filter is presented and incorporated into the *** design process is simple and incorporates significant filter parameters while avoiding iterative *** comparative analysis of the designed filter with conventional L,LC,and iterative LCL filters demonstrates the effectiveness of the modified design *** proposed wind energy system with MPC and LCL filter is simulated in MAtLAB/Simulink and experimentally implemented in the laboratory using the dSpace digital signal processor(DSP)*** simulation and experimental results validate the efficacy of the designed controllers using the measured parameters and show dynamic and steady-state performance under varying wind speeds.

关键词： Wind energy permanent magnet synchronous generator(PMSG) parameter measurement model predictive controller(MPC) LCL filter

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Numerical modeling of the transmission dynamics of drug-sensitive and drug-resistant HSV-2

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Communications in Nonlinear Science and Numerical Simulation 2001年第1期6卷 23-27页

作者： A. B. GUMEL(Department of Mathematics, University of Manitoba, Winnipeg, Manitoba, R3t 2N2, Canada ) Department of Mathematics University of Manitoba Winnipeg Manitoba R3T 2N2 Canada

A competitive finite-difference method will be constructed and used to solve a modified deterministic model for the spread of herpes simplex virus type-2 (HSV-2) within a given population. the model monitors the transmission dynamics and control of drug-sensitive and drug-resistant HSV-2. Unlike the fourth-order Runge-Kutta method (RK4), which fails when the discretization parameters exceed certain values, the novel numerical method to be developed in this paper gives convergent results for all parameter values.

关键词： HSV-2 finite-difference initial-value problem numerical instabilities positivity

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活性炭工艺去除水中典型药品的效能与机理

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化工学报 2012年第4期63卷 1243-1248页

作者：乔铁军张锡辉 Doris W.t.AU 清华大学深圳研究生院广东深圳518055 香港城市大学生物与化学系中国香港999077

药品和个人护理品(PPCPs)因其潜在的环境和健康风险受到了广泛关注。实验选取8种典型药品为对象,采用中试规模的活性炭工艺研究了其去除效果和影响因素。结果表明,活性炭工艺对安替比林、达舒平、舒必利、磺胺甲唑、泰妙菌素和氧苄胺嘧... 详细信息

药品和个人护理品(PPCPs)因其潜在的环境和健康风险受到了广泛关注。实验选取8种典型药品为对象,采用中试规模的活性炭工艺研究了其去除效果和影响因素。结果表明,活性炭工艺对安替比林、达舒平、舒必利、磺胺甲唑、泰妙菌素和氧苄胺嘧啶等的去除率为50%～90%,对林肯霉素和氨糖美辛的去除率均小于35%。典型药品的去除率受到滤速、有机物和pH等因素的影响,其中,氨糖美辛、林肯霉素和泰妙菌素等的去除率受滤速影响较大;磺胺甲唑的去除率受pH影响较大。有机物对典型药品去除率的影响既有促进作用,又有抑制作用。典型药品的物化性质对其去除行为有重要影响,这有利于从分子水平上认识活性炭工艺对典型药品的去除机理。

关键词：药品和个人护理品物化性质活性炭深度处理饮用水

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two synchronous somatostatinomas of the duodenum and pancreatic head in one patient

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World Journal of Gastroenterology 2009年第46期15卷 5859-5863页

作者： Radoje B olovi Slavko V Mati Marjan t Micev Nikica M Grubor Henry Dushan Atkinson Stojan M Latini the First Surgical Clinic Clinical Center of Serbia Surgical Directorate Imperial College School of MedicineSt Mary's HospitalPraed St

Somatostatinomas are extremely rare neuroendocrine tumors of the gastrointestinal tract,f irst described in the pancreas in 1977 and in the duodenum in *** may be functional and cause somatostatinoma or inhibi-tory syndrome,but more frequently are non-functioning pancreatic endocrine tumors that produce somatostatin *** are usually single,malignant,large lesions,frequently associated with metastases,and generally with poor *** present the unique case of a 57-year-old woman with two synchronous non-function-ing somatostatinomas,one solid duodenal lesion and one cystic lesion within the head of the pancreas,that were successfully resected with a pylorus-preserving Whipple's *** secondaries were found in the liver,or in any of the removed regional lymph *** patient had an uneventful recovery,and remains well and symptom-free at 18 mo *** is an extremely rare case of a patient with two synchro-nous somatostatinomas of the duodenum and the *** condition is discussed with reference to the literature.

关键词： Somatostatinoma Duodenal neoplasms Pancreatic neoplasms

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Reconstruction of the Ice Age Glaciation in the Southern Slopes of Mt. Everest, Cho Oyu, Lhotse and Makalu (Himalaya) (Part 1)

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Journal of Mountain Science 2006年第3期3卷 91-124,i0001,i0002页

作者： Matthias Kuhle Geographie/Hochgebirgsgeomorphologie Geographisches Institut der Universitt Goldschmidtstr.5 37077 Gttingen Germany

In the Khumbu- and Khumbakarna Himalaya an ice stream network and valley glacier system has been reconstructed for the last glacial period （W/irmian, Last Ice Age, Isotope stage 4-2, 60- 18 Ka BP, Stage o） with glaciogeomorphological and sedimentological methods. It was a part of the glacier system of the Himalaya and has communicated across transfluence passes with the neighbouring ice stream networks toward the W and E. the ice stream network has also received inflow from the N, from a tibetan ice stream network, by the Kyetrak-Nangpa-Bote Koshi Drangka （Valley） in the W, by the W-Rongbuk glacier valley into the Ngozumpa Drangka （Valley）, by the Central Rongbuk glacier valley into the Khumbu Drangka （Valley） and by the antecedent Arun Nadi transverse-valley in the E of the investigation area. the ice thickness of the valley glacier sections, the surface of which was situated above the snow-line, amounted to lOOO-145o m. the most extended parent valley glaciers have been measured approx. 70 km in length （Dudh Koshi glacier）, 67 km （Barun- Arun glacier） and 80 km （Arun glacier）. the tongue end of the Arun glacier has flowed down to c. 500 m and that of the Dudh Koshi glacier to c. 900 m asl. At heights of the catchment areas of 8481 （or 8475） m （Makalu）, i.e., 8848 （or 8872） m （Mt. Everest, Sagarmatha, Chogolungma） this is a vertical distance of the Ice Age glaciation of c. 8000 m. the steep faces towering up to 2000 m above the névé areas of the 6000-7000 m-high surfaces of the ice stream network were located 2000-5000 m above the ELA. Accordingly, their temperatures were so low, that their rock surfaces were free of flank ice and ice balconies. From the maximum past glacier extension up to the current glacier margins, 13 （altogether 14） glacier stages have been differentiated and in part 14C-dated. they were four glacier stages of the late glacial period, three of the neoglacial period and six of the historical period. By means of 130 medium-sized valley glaciers

关键词：冰河作用珠穆朗玛峰冰河时期地质作用

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the Lower Mantle Minerals in Ophiolite-hosted Diamond

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Acta Geologica Sinica(English Edition) 2015年第A2期89卷 108-109页

作者： YANG Jingsui WIRtH Richard XIONG Fahui tIANYazhou HUANG Zhu ROBINSON Paul t DILEK Yildirim CARMA Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences Germany Department of Geology Miami University Oxford Ohio USA

Ophiolites are fragments of ancient ocean lithosphere emplaced on continental margins, in island arcs or in accretionary prisms, and have long been studied to better understand the evolution of ocean basins and collision of tectonic plates, the processes of mountain building and the occurrence of valuable ore bodies, such as podiform chromitites （Dilek and Fumes, 2011）.

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A Fully Coupled thermomechanical Model of Friction Stir Welding(FSW) and Numerical Studies on Process Parameters of Lightweight Aluminum Alloy Joints

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Acta Metallurgica Sinica(English Letters) 2018年第1期31卷 1-18页

作者： Saad B.Aziz Mohammad W.Dewan Daniel J.Huggett Muhammad A.Wahab Ayman M.Okeil t.Warren Liao Department of Mechanical and Industrial Engineering Louisiana State University Department of Civil and Environmental Engineering Louisiana State University

this paper presents a new thermomechanical model of friction stir welding which is capable of simulating the three major steps of friction stir welding （FSW） process, i.e., plunge, dwell, and travel stages. A rate-dependent Johnson- Cook constitutive model is chosen to capture elasto-plastic work deformations during FSW. two different weld schedules （i.e., plunge rate, rotational speed, and weld speed） are validated by comparing simulated temperature profiles with experimental results. Based on this model, the influences of various welding parameters on temperatures and energy generation during the welding process are investigated. Numerical results show that maximum temperature in FSW process increases with the decrease in plunge rate, and the frictional energy increases almost linearly with respect to time for different rotational speeds. Furthermore, low rotational speeds cause inadequate temperature distribution due to low frictional and plastic dissipation energy which eventually results in weld defects. When both the weld speed and rotational speed are increased, the contribution of plastic dissipation energy increases significantly and improved weld quality can be expected.

关键词： Aluminum alloy Friction stir welding temperature distribution Plastic energy Frictional energy Rate-dependent model Friction modeling

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Perigastric extraskeletal Ewing's sarcoma: A case report

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World Journal of Gastroenterology 2009年第2期15卷 245-247页

作者： Radoje B Colovic Nikica M Grubor Marjan t Micev Slavko V Matic Henry Dushan Edward Atkinson Stojan M Latincic Institute for Digestive Diseases Clinical Center of Serbia Koste Todorovica 6 Belgrade 11000 Serbia Imperial College School of Medicine St Mary's Hospital Praed Street London W2 1NY United Kingdom

Ewing's sarcoma (ES) is a neoplasm of undifferentiated small round cells, which occurs in the bones and deep soft tissues of children and adolescents. We present a rare case of a 44-year-old woman with gastric ES presenting with epigastric pain and weight loss. Ultrasound and computed tomography scans indicated a solid/cystic mass in the pancreatic tail. At laparotomy, the tumor was found attached to the posterior surface of the stomach, completely free from the pancreas, with no lymphadenopathy or local metastases. the polynodal, partly pseudocystic, dark-red soft tumor was excised. Histopathology revealed an anaplastic small-round-cell tumor with strong membranous CD99 immunoexpression. Additionally, there was patchy immunostaining for S-100 protein, vimentin, protein gene product (PGP) 9.5 and neuron-specifi c enolase, and weak focal CD117 cytoplasmic immunoreactivity. the patient had no adjuvant chemotherapy; her postoperative recovery was uneventful, and she remains symptom-free, and without any sign of recurrence at 20 mo. to the best of our knowledge, this is only the third ever case of gastric ES.

关键词： Stomach Extraskeletal Ewing's sarcoma

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Self-lubricating bidirectional carbon fiber reinforced smart aluminum composites by squeeze infiltration process

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Journal of Materials Science & technology 2019年第11期35卷 2559-2569页

作者： K.M.Sree Manu L.Ajay Raag t.P.D.Rajan B.C.Pai Vijay Petley Shweta Namdeo Verma CSIR-National Institute for Interdisciplinary Science and technology TrivandrumIndia Gas turbine Research Establishment(GtRE) BangaloreIndia

Self-lubrication is one of the smart material properties required for producing components with enhanced wear resistance and low coefficient of ***(BD)satin weave polyacrylonitrile(PAN)based carbon fiber(Cf)fabric preform was successfully infiltrated with Al 6061 alloy by squeeze infiltration *** infiltrated composite shows uniform distribution of carbon fibers in the matrix with the elimination of porosities,fiber damage and close control on the formation of deleterious aluminum carbide(Al4C3)***/Al composite exhibits remarkable wear resistance compared to unreinforced alloy due to the formation of self-lubricating tribolayer on the pin surface,which intercepts the contact of matrix metal to counter *** BD carbon fiber enhanced the hardness and compressive strength of the composite by restraining the plastic flow behavior of *** resolution transmission electron microscopy shows the presence of Al2O3 and MgAl2O4 spinel,confirmed by EDS and SAD pattern,at the composite *** composite shows a lower density of 2.16 g/cm^3 which is a major ad vantage for weight reduction compared to the monolithic alloy(2.7 g/cm^3).

关键词： Metal matrix composites Squeeze infiltration Aluminum Carbon fiber fabric tribology Microstructure

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Subcycle control of terahertz waveform polarization using all-optically induced transient metamaterials

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Light(Science & Applications) 2014年第1期3卷 309-313页

作者： N Kamaraju Andrea Rubano Linke Jian Surajit Saha t Venkatesan Jan Notzold R Kramer Campen Martin Wolf tobias Kampfrath Fritz Haber Institute of the Max Planck Society 14195 BerlinGermany Department of Electrical Computerand Systems EngineeringRensselaer Polytechnic InstituteTroyNY 12180USA CNR-SPIN Dipartimento di FisicaUniversita`di Napoli Federico IINapoliItaly NUSNNI-Nanocore National University of SingaporeSingapore

Coherent radiation with frequencies ranging from 0.3 to 30 tHz has recently become accessible using femtosecond laser *** terahertz(tHz)waves have already been applied in spectroscopy and imaging and can be manipulated using static optical elements such as lenses,polarizers and ***,ultrafast modulation of tHz radiation is required as well,for instance,in short-range wireless communication or for preparing shaped tHz transients for the coherent control of numerous material ***,we demonstrate an all-optically created transient metamaterial that allows us to manipulate the polarization of tHz waveforms with subcycle switch-on *** polarization-modulated pulses are potentially interesting for controlling elementary motions such as the vibration of crystal lattices,the rotation of molecules and the precession of spins.

关键词： terahertz metamaterial terahertz optics terahertz polarization control

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