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The Power Supply System for the J-TEXT Poloidal Field

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Plasma Science and Technology 2009年第1期11卷 100-103页

作者：张明庄革于克训邱胜顺潘垣 Key lab.of Fusion and Advanced Electromagnetic Technology of Ministry of Education College of Electrical and Electronic EngineeringHuazhong University of Science and Technology

Joint-TEXT （J-TEXT） is a medium-sized tokamak constructed at Huazhong University of Science and Technology. At present, the poloidal field power supply consists of three subsystem sets, namely Ohmic heating field power supply, vertical field power supply, and horizontal field power supply. The structure and function of the poloidal field （PF） power supply as well as the updated control system of the power supply is described. The new scheme uses the realtime feedback control method for the poloidal field power supply. The experimental results show that the poloidal field energized by poloidal field power supply meets the J-TEXT operational requirement perfectly.

关键词： J-TEXT poloidal field power supply control

ERGODIC CAPACITY FORMULA OF MIMO-OFDM SYSTEMS UNDER CORRELATED FREQUENCY SELECTIVE RAYLEIGH FADING CHANNELS

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Journal of Electronics(China) 2007年第5期24卷 588-592页

作者： Pang Jiyong Li Jiandong Zhao Linjing Broadband Wireless Communications lab Information Science InstituteState Key Lab of Integrated Service Networks Xidian University Xi＇an 710071 China

An explicit formula for the ergodic capacity of Orthogonal Frequency Division Multiplexing (OFDM)-based Multiple-Input Multiple-Output (MIMO) systems under correlated frequency selective Rayleigh channels is derived,by simplifying the channel response matrix in frequency domain into the so-called Kronecker model composed of three kinds of correlations,*** tap gain correlation and spatial fading correlations at both transmitter and *** derived formula is very simple and convenient for one to estimate the effects of all three kinds of correlations on MIMO-OFDM *** taps are independent,there is a very simple expression for the ergodic *** case of tap correlation,the capacity formula could be further given in an integral *** validity of the new formula is verified and the effects of correlations,delay spread as well as the number of subcarriers on the ergodic capacity are evaluated via Monte Carlo simulations.

关键词：各态历经容量公式输出输入频率

Broadening of Photoluminescence by Nonhomogeneous Size Distribution of Self-Assembled InAs Quantum Dots

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Chinese Physics Letters 2008年第8期25卷 3059-3062页

作者：杨希峰刘昭麟陈平平陈效双李天信陆卫 National lab.for Infrared Physics Shanghai Institute of Technical Physics Chinese Academy of Sciences 500 Yutian Road Shanghai 200083

The photoluminescence spectrum （PL） of InAs quantum dots （QDs） at 80 K is studied by comparison between the theoretical calculation and experimental measurement. The Gaussian line shape is used to approximate the size distribution of QDs. Its mean volume and the standard full width at half maximum （FWHM） of the PL spectrum. size deviation are well correlated with the peak and The experimental PL spectrum is well reproduced by the theoretical model based on the effect mass approximation including the size distribution without any adjustable parameters. Compared with the standard size deviation value σ = 9 × 10^-2 determined by atomic force microscopic method a small value σ = 7 × 10^-2 is obtained by the best fitting process from the measured and calculated PL spectra.

关键词： ELECTRONIC-STRUCTURE OPTICAL-PROPERTIES INFRARED PHOTODETECTORS TEMPERATURE-DEPENDENCE GAAS RELAXATION LASERS ENERGY

Words apart:Standardizing forestry terms and definitions across European biodiversity studies

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森林生态系统:英文版 2023年第4期10卷 459-471页

作者： Giovanni Trentanovi Thomas Campagnaro Tommaso Sitzia Francesco Chianucci Giorgio Vacchiano Christian Ammer MichałCiach Thomas ANagel Miren del Río Yoan Paillet Silvana Munzi Kris Vandekerkhove Andrés Bravo-Oviedo Andrea Cutini Ettore D'Andrea Pallieter De Smedt Inken Doerfler Dimitris Fotakis Jacob Heilmann-Clausen Jeňýk Hofmeister Jan Hošek Philippe Janssen Sebastian Kepfer-Rojas Nathalie Korboulewsky Bence Kovács Daniel Kozák Thibault Lachat Anders Mårell Radim Matula Martin Mikoláš Björn Nordén PéterÓdor x Marko Perović Elisabeth Pötzelsberger Peter Schall Miroslav Svoboda Flóra Tinya Mariana Ujházyová Sabina Burrascano research Institute on Terrestrial Ecosystems-National research Council(IRET-CNR) Via Madonna Del Piano 1950019Sesto FiorentinoFIItaly Department of Land EnvironmentAgriculture and ForestryUniversitàdegli Studi di PadovaViale Dell’Università1635020LegnaroPDItaly National Biodiversity Future Center Piazza Marina 6190133PalermoItaly CREA research Centre for Forestry and Wood Viale S.Margherita 8052100ArezzoItaly Department of Agricultural and Environmental Sciences(DISAA) University of MilanVia Celoria 220133MilanItaly Silviculture and Forest Ecology of the Temperate Zones University of GöttingenGermany Department of Forest Biodiversity Faculty of ForestryUniversity of Agricultureal.29 Listopada 4631-425KrakówPoland Department of Forestry and Renewable Forest Resources Biotechnical FacultyUniversity of LjubljanaVecna pot 831000LjubljanaSlovenia Instituto de Ciencias Forestales(ICIFOR-INIA) CSICCtra.de la Coruña Km 7.528040MadridSpain University Grenoble Alpes LessemINRAE2 Rue de la Papeterie38402 Saint-Martin-d'HèresFrance Centro Interuniversitário de História Das Ciências e da Tecnologia Faculdade de CiênciasUniversidade de LisboaPortugal Centre for Ecology Evolution and Environmental ChangesFaculdade de Ciências&CHANGE-Global Change and Sustainability InstituteUniversidade de LisboaPortugal research Institute for Nature and Forest(INBO) Havenlaan 88 Bus 731000BrusselBelgium Department of Biogeography and Global Change National Museum of Natural Sciences-CSICC/Serrano 115bis28006MadridSpain research Institute on Terrestrial Ecosystems-National research Council(IRET-CNR) Via G.Marconi N.205010PoranoTRItaly Forest&Nature lab Department of EnvironmentGhent UniversityGeraardsbergsesteenweg 2679090GontrodeBelgium Institute of Biology and Environmental Science Vegetation Science&Nature ConservationUniversity of OldenburgAmmerländer Heerstraße 114-11826129OldenburgGermany Forest research Institute Hellenic Agricultural Organization DimitraVassilikaThessal

Forest biodiversity studies conducted across Europe use a multitude of forestry terms,often *** hinders the comparability across studies and makes the assessment of the impacts of forest management on biodiversity highly *** attempts to standardize forestry and stand description terminology mostly used a top-down approach that did not account for the perspectives and approaches of forest biodiversity *** work aims to establish common standards for silvicultural and vegetation definitions,creating a shared conceptual framework for a consistent study on the effects of forest management on *** have identified both strengths and weaknesses of the silvicultural and vegetation information provided in forest biodiversity *** quantitative data on forest biomass and dominant tree species are frequently included,information on silvicultural activities and vegetation composition is often lacking,shallow,or based on broad and heterogeneous *** discuss the existing classifications and their use in European forest biodiversity studies through a novel bottom-up and top-driven review process,and ultimately propose a common *** will enhance the comparability of forest biodiversity studies in Europe,and puts the basis for effective implementation and monitoring of sustainable forest management *** standards here proposed are potentially adaptable and applicable to other geographical areas and could be extended to other forest interventions.

关键词： Forest management Multi-taxon Terminology Silviculture Data harmonization

Novel modal interferometer based on ring-core photonic crystal fiber

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Chinese Optics Letters 2010年第10期8卷 986-988页

作者：陈卫国娄淑琴王立文简水生 Institute of Lightwave Technology Key Lab of All Optical Network and Advanced Telecommunication Network Ministry of Education Beijing Jiaotong University

An original design of ring-core photonic crystal fiber （RPCF） is proposed. By splicing a section of the homemade RPCF between two segments of single mode fibers （SMFs）, a simple modal interferometer is presented and experimentally demonstrated. Owing to the effects of the collapsed region, the ring modes in RPCF can be effectively activated. To our knowledge, it is the first time to demonstrate the modal interferometer based on the interference between the ring modes, which is different from the previously reported interferometers based on the interference between core modes or cladding modes. The temperature and strain characteristics of the interferometers with different lengths of RPCF are investigated.

关键词： Crystal whiskers Interferometers Photonic crystals Single mode fibers

Effects of Sequence Distribution and Physical Aging on Physical Properties of PES/PEES Random, Block, and Alternative Copolymers

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Chemical research in Chinese Universities 2006年第6期22卷 787-791页

作者： ZHOU Xiao-ming JIANG Zhen-hua Alan G. MacDiarmid lab College of Chemistry Jilin University Changchun 130012 P. R. China

The random, block, and alternative copolymers of poly ether sulfone（PES） and poly ether ether sulfone（PEES） were synthesized v/a three kinds of methods. The chemical structures of the three kinds of copolymers were characterized by ^13C NMR. Three kinds of PES/PEES copolymers（ Tg =215 ℃ ）, which were almost identical in composition but different in sequence distribution, were used. Their physical aging process was studied by differential scanning calorimetry（DSC） at three aging temperatures ranging between Tg -15 ℃ and Tg -25℃. The experimental results reveal that the alternative copolymer shows a lower enthalpy relaxation time 〈T〉 and apparent activation energy when compared with the random and block copolymers. The result of the electron-microscopy investigation of the three copolymers that were treated at 200 ℃ for 96 h indicates that the molecular aggregation of the copolymers changed from a randomly coiled amorphous phase to an ordered phase, and the ordered structure of the alternative copolymer was more distinct than that of the random phase. The experimental results of this study suggest that the motion of the sagments is affected by the different molecular-chain sequence distribution.

关键词： Physical aging Apparent activation energy Sequence distribution

An Encryption-Decryption Method Using XOR Gate Based on the XPM between O-Band and C-Band Light Waves

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Chinese Physics Letters 2009年第7期26卷 181-183页

作者：王亚平吴重庆王智王拥军杨双收 Institute of Optical Information Key Lab of Luminescence and Optical Information Technology (Ministry of education) Beijing Jiaotong University Beijing 100044

An all-optical encryption-decryption method using an exclusive-or gate based on the cross-phase modulation between O-band and C-band light waves is proposed. The feasibility of the encryptionecryption technique is verified by handling binary signals at 2.5 Gbps, with less than 3dB penalty of extinction ratio and i dB polarization dependent loss.

关键词： sea surface nonliear interaction numerical method

Study on the saturation characteristics of high-speed uni-traveling-carrier photodiodes based on field screening analysis

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Chinese Optics Letters 2011年第8期9卷 79-82页

作者：石拓熊兵孙长征罗毅 Tsinghua National lab.ratory for Information Science and Technology State Key Lab on Integrated OptoelectronicsDepartment of Electronic EngineeringTsinghua University

A back-illuminated mesa-structure InGaAs/InP charge-compensated uni-traveling-carrier （UTC） photodi- ode （PD） is fabricated, and its saturation characteristics are investigated. The responsivity of the 40-μm- diameter PD is as high as 0.83 A/W, and the direct current （DC） saturation current is up to 275 mA. The 1-dB compression point at the 3-dB cutoff frequency of 9 GHz is measured to be 100 mA, corresponding to an output radio frequency （RF） power of up to 20.1 dBm. According to the calculated electric field distributions in the depleted region under both DC and alternating current （AC） conditions, the saturation of the UTC-PD is cansed hv cnmnlete field screening at high optical iniectinn levels

关键词： DC power transmission Electric fields Photodiodes

Simulation of Low-Voltage Arc Plasma During Contact Opening Progress

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Plasma Science and Technology 2007年第6期9卷 649-652页

作者：吴翊荣命哲孙志强王小华李剑王建华 State Key lab.of Electrical Insulation and Power Equipment School of Electrical EngineeringXi'an Jiaotong UniversityXi'an 710049China

This paper focuses on the simulation of the low-voltage arc with an opening contact. A controllab.e experiment setup with a rotating contact is designed to investigate the arc behaviour. Supported by the experiment, the phenomena of arc elongation and commutation in the case of rotating contact are simulated with the dynamic grid technique introduced. Under the given condition of the external magnetic field and the contact rotating velocity, the stagnation and rapid jump of two arc roots are observed by the calculated and experimental arc root displacement. The voltage of arc column can be divided into four phases and its sharp rising progress comes from the increase of the displacement difference between two arc roots in x direction.

关键词： arc plasma low-voltage switching devices