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Magnetic field Gradient and Curvature-Driven Drift Modes in Toroidal Plasmas

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Chinese Physics Letters 2004年第8期21卷 1575-1577页

作者：王爱科 H.Sanuki 董家齐 f.zonca K.Itoh SouthwesternInstituteofPhysics POBox432Chengdu610041 NationalInstituteforfusionScience TokiGifu509-5292Japan ENEAC.R.frascati C.P.6500044FrascatiRomeItaly

A new kind of instability driven by the magnetic field gradient and curvature (MfGC) in toroidal plasmas is presented. It is found that the MfGC drift modes possess finite growth rates even if the plasma pressure gradient vanishes. In addition, the effects of plasma pressure gradient and safety factor on the MfGC modes have been analysed numerically.

关键词： Plasma physics

APolygonal Discontinuous Galerkin formulation for Contact Mechanics in fluid-Structure Interaction Problems

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Communications in Computational Physics 2021年第6期30卷 1-33页

作者： Stefano zonca Paola fAntonietti Christian Vergara MOX Dipartimento di MatematicaPolitecnico di MilanoItaly LABS Dipartimento di ChimicaMateriali e Ingegneria Chimica“Giulio Natta”Politecnico di MilanoItaly

In this work,we propose a formulation based on the Polygonal Discontinuous Galerkin(PolyDG)method for contact mechanics that arises in fluid-structure interaction *** particular,we introduce a consistent penalization approach to treat the frictionless contact between immersed structures that undergo large *** key feature of the method is that the contact condition can be naturally embedded in the PolyDG formulation,allowing to easily support polygonal/polyhedral *** proposed approach introduced a fixed background mesh for the fluid problem overlapped by the structure grid that is able to move independently of the fluid *** assess the validity of the proposed approach,we report the results of several numerical experiments obtained in the case of contact between flexible structures immersed in a fluid.

关键词： Polygonal Discontinuous Galerkin method fluid-structure interaction contact mechanics

Ectopic liver: Different manifestations, one solution

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World Journal of Gastroenterology 2013年第38期19卷 6485-6489页

作者： Pavel zonca Lubomir Martinek Peter Ihnat Jan fleege Department of Surgery University Hospital Ostrava70852 OstravaCzech Republic Department of Surgical Studies Faculty of MedicineUniversity of Ostrava70300 OstravaCzech Republic MVZ Zentrum für Pathologie und Zytodiagnostik GmbH 50996 KlnGermany

Developmental abnormalities are rare in the *** study presents two case reports of ectopic *** first case was a 31-year-old male with clinical indication for laparoscopic *** identified a perforated appendix and an unknown tumorous lesion in the ligamentum hepato *** patient underwent a laparoscopic appendectomy,intraoperative lavage of the peritoneal cavity,and extirpation of the lesion in the ligamentum hepato *** examination of the excised tumor revealed that it comprised liver tissue with fibrinous *** tumor was completely separate from the liver with no *** was classified as an ectopic *** further therapy was *** second case was a59-year-old male with a tumor on the upper pole of the spleen,incidentally diagnosed in an ultrasound *** biopsy raised suspicion of hepatocellular carcinoma.A positron emission tomography-computed tomography examination revealed accumulation of f-18 fluorodeoxyglucose only in the *** patient underwent a splenectomy with a resection and reconstruction of *** the hepatocellular carcinoma was confirmed,adjuvant therapy(sorafenib)was *** operations and postoperative recoveries were uncomplicated in both *** the low incidence of ectopic liver and rare complications,it is necessary to maintain awareness of this *** potential malignancy risk for ectopic liver tissue is the basis for radical surgical *** for hepatocellular carcinoma in an ectopic liver follows the same guidelines as those followed for treating the"mother"liver.

关键词： Ectopic Liver Hepatocellular carcinoma Diagnostic Treatment

Study of Kinetic Shear Alfvén Modes Driven by Ion Temperature Gradient in Tokamak Plasmas

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中国核科技报告 1999年第S3期 3-5页

作者： CHEN f. zonca f. United States of America. Rome Department of Physics ＆ Astronomy University of California Irvine Italy. Associazione EURATOM-ENEA sulla fusione frascati

Discrete kinetic shear Alfv(?)n modes driven by ion temperature gradient (AITG) is investigated in the full gyrokinetic limit. It is shown that AITG instability may occur when the plasma pressure gradient is well below the threshold value for ideal magnetohydrodynamics (MHD) ballooning instabilities, and that the critical magnetic shear required to completely stabilize the former is significantly higher than that for the latter. In addition, finite-β(=plasma pressure/magnetic pressure) effects on toroidal electrostaticion temperature gradient (ITG) modes are

关键词： AITG MHD Ion temperature gradient

Hydro-wind Optimal Operation for Joint Bidding in Day-ahead Market: Storage Efficiency and Impact of Wind forecasting Uncertainty

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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 142-149页

作者： António Cerejo Sílvio J.P.S.Mariano Pedro M.S.Carvalho Maria R.A.Calado Technical-Scientific Unity of Electrical and Industrial Engineering Polytechnic Institute of Castelo BrancoAvenida do Empresário6000-767 Castelo BrancoPortugal Department of Electromechanical Engineering University of Beira Interior and Instituto de TelecomunicacoesCalcada Fonte do Lameiro6201-001 CovilhaPortugal Department of Electrical and Computer Engineering Instituto Superior Técnicoand INESC-IDUniversity of LisbonAv.Rovisco Pais1049-001 LisbonPortuga

Wind power production is *** imbalance between committed and delivered energy in pool markets leads to the increase of system costs,which must be incurred by defaulting producers,thereby decreasing their *** avoid this situation,wind producers can submit their bids together with hydro *** the mismatches between the predicted and supplied wind power can be used by hydro producers,turbining or pumping such differences when *** study formulates the problem of hydro-wind production optimization in operation contexts of pool *** problem is solved for a simple three-reservoir cascade case to discuss optimization *** results show a depreciation in optimal revenues from hydro power when wind forecasting is *** depreciation is caused by an asymmetry in optimal revenues from positive and negative wind power *** problem of neutralizing the effect of forecasting uncertainty is subsequently formulated and solved for the three-reservoir *** results are discussed to conclude the impacts of uncertainty on joint bidding in pool market contexts.

关键词： Optimization hydro power wind power uncertainty joint bidding pool market

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Soil texture prediction through stratification of a regional soil spectral library

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Pedosphere 2022年第2期32卷 294-306页

作者： José Janderson ferreira COSTA élvio GIASSON Elisangela Benedet DA SILVA Tales TIECHER Antonny francisco Sampaio DE SENA Ryshardson Geovane Pereira de Oliveira E SILVA Department of Soil Science Faculty of AgronomyUniversity of Rio Grande do SulBento Gonçalves Avenue 7712Porto Alegre 91540-000Brazil Agricultural Research and Rural Extension Corporation of Santa Catarina Rodovia Admar Gonzaga 1347FlorianópolisSanta Catarina 88034-901Brazil

Knowing the spatial distribution of soil texture,which is a physical property,is essential to support agricultural and environmental decision *** texture can be estimated using visible,near infrared,and shortwave infrared(Vis-NIR-SWIR)***,the performance of spectroscopic models is variable because of soil ***,few studies address the effects of soil sample variability on the performance of the models,especially for larger spectral libraries that include soils that are more ***,the objectives of this study were to:i)apply Vis-based color parameters on the stratification of a regional soil spectral library;ii)evaluate the performance of the predictive models generated from the spectral library stratification;iii)compare the performance of stratified models(SMs)and the model without stratification(WSM),and iv)explain possible changes in prediction accuracy based on the ***,a regional soil spectral library with 1535 samples from the State of Santa Catarina,Brazil was *** reflectance data were obtained by Vis-NIR-SWIR spectroscopy in the laboratory using a spectroradiometer covering the 350–2500 nm spectral ***,silt,and clay fractions were determined using the pipette ***-two components of color parameters were derived from the Vis spectrum using the colorimetric models.A cubist regression algorithm was used to assess the accuracy of the applicability of the initial models(SMs and WSM)and of the validation between the *** order derivatives(fODs)at 0.5,1.5,and 2 intervals were used to explain possible changes in the performance of the *** SMs with higher contents of clay and iron oxides obtained the highest accuracy,and the most important spectral bands were identified,mainly in the 480–550 and 850–900 nm ranges and the 1400,1900,and 2200 nm ***,stratification of soil spectral libraries is a good strategy to improve regional assessments of soil resou

关键词： color parameters cubist regression fractional order derivatives soil spectroscopy spectroscopic model stratified model Vis-NIR-SWIR

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fishbone Instability Excited by Barely Trapped Electrons

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2006年第1期 113-115页

作者： WANG Zhongtian LONG Yongxing DONG Jiaqi WANG Long zonca f. 不详 Institute of Physics Chinese Academy of Sciences Beijing 100080 China Associazione EURATOM-ENEA Sulla Fusione C.P. 65-00044 Frascati Rome Italy

1 Introduction Internal kink mode driven by barely trapped suprakthermal electrons is reported on D Ⅲ-D tokama . This instability is most active when electron cyclotron current drive （ ECCD ） is applied on the high field side of the flux surface. It has a bursting behavior with poloidal/toroidal mode number m/n = 1/1. In positive magnetic shear plasma this mode becomes fishbone instability.

关键词：电子核反应装置核物理学回旋加速器

Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas f.Sadreev Yong Li Andrey E.Miroshnichenko School of Physics and Electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University School of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Combining Rectangular and Triangular Image Regions to Perform Real-Time face Detection

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Combining Rectangular and Triangular Image Regions to Perfor...