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Phased Array Feed Experiments and Galactic HI Observations

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Research in Astronomy and Astrophysics 2023年第8期23卷 297-307页

作者： B.Liu H.W.Xi D.J.Ding Z.W.Wang S.H.Yu Y.Zhu L.Yu X.Zhang J.L.Li L.J.Liu q.su Y.Wu C.J.Jin B.Peng National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China The 54th Research Institute of China Electronic Technology Group Cooperation Shijiazhuang 050081China

The Phased Array Feed(PAF)is considered as one of the next generation receivers for radio telescopes,which can significantly enlarge the instantaneous Field-of-View of large aperture single dish radio telescopes and enable more flexible observing *** efforts on PAF development for radio telescopes have been made for more than two decades and have become more and more *** report the development of an ambient-temperature 19 element L-band PAF system and the experimental results including its far field beam pattern and system temperature measurement,which achieve the *** the aperture array beam-forming method,we demonstrate a wide-field Galactic HI observations in the radio camera *** results indicate that this system might be applicable for strong Galactic transient *** system could be directly equipped to large telescopes like the Five-hundred-meter Aperture Spherical radio Telescope(FAST)and FAST array in the future.

关键词： instrumentation detectors-techniques imaging spectroscopy-line profiles

Dynamic Coordination of Uncalibrated Hand/Eye Robotic System Based on Neural Network

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Journal of Systems Engineering and Electronics 2001年第3期12卷 45-50页

作者： su, J. Pan, q. Xi, Y. Institute of Automation Shanghai Jiaotong University Shanghai 200030 China

A nonlinear visual mapping model is presented to replace the image Jacobian relation for uncalibrated hand/eye coordination. A new visual tracking controller based on artificial neural network is designed. Simulation results show that this method can drive the static tracking error to zero quickly and keep good robustness and adaptability at the same time. In addition, the algorithm is very easy to be implemented with low computational complexity.

关键词： Adaptive algorithms Computational complexity Computer simulation Coordinate measuring machines Error detection Mathematical models Neural networks Robotic arms Robustness (control systems) Stereo vision

Study of primary leiomyosarcoma induced by MNNG in BALB/C nude mice

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World Journal of Gastroenterology 2000年第1期6卷 128-130页

作者： Zhu JS su q Zhou JG Hu PL Xu JH Institute of Oncology Hengyang Medical CollegeHengyang 421001China

INTRODUCTIONIt has been well known that MNNG is one of thestrong and multipotential carcinogens that havebeen frequently reported inducing malignant *** have successfully induced rat and doggastric adenocarcinomas,squ... 详细信息

关键词： subject headings leiomyosarcoma stomach neoplasms MNNG BALB/C nude mice

Analysis of extreme ultraviolet spectral profiles of laser-produced Cr plasmas

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Chinese Physics B 2019年第7期28卷 319-323页

作者： L Wu M G su q Min S q Cao S q He D X sun C Z Dong Key Laboratory of Atomic and Molecular Physics & Functional Material of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal University

Radiation from laser-produced plasmas was examined as a potential wavelength calibration source for spectrographs in the extreme ultraviolet(EUV) ***, the EUV emission of chromium(Cr) plasmas was acquired via spatiotemporally resolved emission *** the aid of Cowan and flexible atomic code(FAC) structure calculations,and a comparative analysis with the simulated spectra, emission peaks in the 6.5–15.0 nm range were identified as 3 p–4 d, 5 d and 3 p–4 s transition lines from Cr5+–Cr10+ions.A normalized Boltzmann distribution among the excited states and a steady-state collisional-radiative model were assumed for the spectral simulations, and used to estimate the electron temperature and density in the *** results indicate that several relatively isolated emission lines of highly charged ions would be useful for EUV wavelength calibration.

关键词： laser-produced plasmas highly charged ions extreme ultraviolet wavelength calibration

First-Principles Study of Phase Stability and Mechanical Property of Co_3(Al,W) Precipitates with Different Ratio of Al to W in Co Base Alloys

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稀有金属材料与工程 2009年第A03期38卷 1-4页

作者： Yao q.su X M Yan Y Zhao L W sun J Shanghai Jiaotong University Shanghai 200240 China

The energetics, electronic structure and mechanical property of Co3(Al,W) precipitates with different ratio of Al to W in Co base alloys were investigated by the method of supercell and augmented plane waves plus local orbitals within generalized gradient approximation. The calculated results show that the L12 Co3(Al,W) precipitate is the most stable when the ratio of Al to W is equal to 1. When the content of W is higher than 18.5 at%, the L12 and hexagonal structures co-exist in Co3(Al,W) precipitates at 1173 K. It is also shown that the L12 ordered Co3(Al,W) precipitates have an obvious strengthening effect in the disordered fcc cobalt matrix.

关键词：铝电子结构力学性能碳酸

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美国的能源互联网与电力市场

科学通报 2016年第11期61卷 1210-1221页

作者： su Wen Cong HUANG Alex q. University of Michigan-Dearborn Michigan 48128 USA North Carolina State University North Carolina 27606 USA

受早期计算机工业发展的启发,美国北卡罗莱纳州立大学的Alex ***教授在2007年提出了"能源互联网"(Energy Internet)这一概念,并主持开发了未来可再生电能传输及管理系统(FREEDM Systems).作为一个全新的居民配电基础设施,能源互联网支... 详细信息

受早期计算机工业发展的启发,美国北卡罗莱纳州立大学的Alex ***教授在2007年提出了"能源互联网"(Energy Internet)这一概念,并主持开发了未来可再生电能传输及管理系统(FREEDM Systems).作为一个全新的居民配电基础设施,能源互联网支持大规模的分布式可再生能源的即插即用.能源互联网的发展依赖于一系列萌芽期的新兴技术,如双向通信、双向潮流,电力系统控制和电力电子器件技术等.能源互联网的全面建设发展给我们带来了机遇和挑战.值得一提的是,在能源互联网的蓝图下,能源细胞(Energy Cell)作为全新的电力市场参与者,将大大促进了多样化,高度市场化的零售电市场发展.个体居民用户将在未来的电力市场当中扮演及其重要的角色.

关键词：能源互联网能源细胞智能电网电力市场可再生能源

EFFECT OF SILICON ON PRODUCING DUCTILE IRON WITH COMPLEX STRUCTURE OF BAINITE AND MARTENSITE

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 25-28页

作者： Y.P.Zhang J.X.Zhu Y.q.Wang J.Y.su Xi'an Univ of Technology Xi'an China

This paper deals with an important role of silicon in producing ductile iron with quenched complex structure of bainite and martensite. The samples are cast in permanent mold and quenched in solution of sodium silicate. The result of thc experiments shows that the austenizing temperature should rise with increasing silicon content, otherwise much undissolved ferrite is present in the matrix after quenching. However the undissolvec ferrite can be decreased greatly or even eliminated by adding appropriate amount of ooron. On this condition, the amount of bainite gets increasing and the amount of residual austenite decreasing with the silicon cortent increasing. An approach has also been made to the mechanism of the effect of silicon on the transformation of bainite in ductile iron. The T.T.T. curves measured show that the increase of sllicon content causes the curve to shift to the left. This is quite different from the fact in steel.

关键词： ductile iron,silicon content bainite martensite

Cleaning Radio Frequency Interference in Pulsar-Folded Data Based on the Conditional Random Fields with an Adaptive Prior

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Research in Astronomy and Astrophysics 2023年第10期23卷 184-191页

作者： Xue Chen J.L.Han W.q.su Z.L.Yang D.J.Zhou National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of FAST NAOCChinese Academy of SciencesBeijing 100101China

Radio astronomy observations are frequently impacted by radio frequency interference(RFI).We propose a novel method,named 2σCRF,for cleaning RFI in the folded data of pulsar observations,utilizing a Bayesian-based model called conditional random fields(CRFs).This algorithm minimizes the“energy”of every pixel given an initial *** standard deviations(i.e.,rms values)of the folded pulsar data are utilized as pixels for all subintegrations and ***-RFI data without obvious interference is treated as“background noise,”while RFI-affected data have different classes due to their exceptional rms *** initial labeling can be automated and is adaptive to the actual *** CRF algorithm optimizes the label category for each pixel of the image with the prior initial *** demonstrate the efficacy of the proposed method on pulsar folded data obtained from Five-hundred-meter Aperture Spherical radio Telescope *** can effectively recognize and tag various categories of RFIs,including broadband or narrowband,constant or instantaneous,and even weak RFIs that are unrecognizable in some pixels but picked out based on their *** results are comparable to those obtained via manual labeling but without the need for human intervention,saving time and effort.

关键词： methods:data analysis techniques:image processing (stars:)pulsars:general

EFFECT OF CHROMIUM AND BORON ON ENVIRONMENTAL EMBRITTLEMENT OF FORGED Fe_3Al

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Acta Metallurgica Sinica(English Letters) 1997年第3期10卷 188-191页

作者： J.q. su S.J Gao and Z.q. Hu (Liaoning Key Laboratory for Materials and Hydrogen, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China)(National Key Laboratory for RSA, Institute of Metal Research, Chinese Academy of Sciences, Inst of Metal Research Chinese Acad of Sciences Shenyang China

The effects of addition of chromium or boron on room temperature tensile properties,fracture behavior and susceptibility to test environments (air vs. vacuuwi of forged Fe3Al have been investigated. The results indicated that both chromium and boron result in increasing room temperuture ductility and fracture strength of the Fe3Al alloy whether tested in air or in vacuum. The susceptibility to test envimnment was described with the embrittlement index I: I=(δv-δA)/δv. The embrittlement indexes, for Fe-30Al, Fe-30Al-4Cr and Fe-30Al-0. 13B (at. %), are 24%, 37% and 29%,respectively. Scanning electron microscope examination of fracture surface revealed that the fracture mode of the three alloys remains unchanged, and all of them exhibited a transgranular cleavage fracture mode when tested in vacuum or air.

关键词： chromium boron Fe_3Al enviromental embrittlement