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Journal of Energy and Power Engineering 2011年第6期5卷 548-553页

作者： Y.L. Zhao q. yu C.G. Zhao Electric Engineering Department Northeast Agricultural University Harbin 150001 China Harbin Electric Power Bureau Harbin 150001 China

Due to the inherent complexity, traditional ant colony optimization （ACO） algorithm is inadequate and insufficient to the reactive power optimization for distribution network. Therefore, firstly the ACO algorithm is improved in two aspects： pheromone mutation and re-initialization strategy. Then the thought of differential evolution （DE） algorithm is proposed to be merged into ACO, and by producing new individuals with random deviation disturbance of DE, pheromone quantity left by ants is disturbed appropriately, to search the optimal path, by which the ability of search having been improved. The proposed algorithm is tested on IEEE30-hus system and actual distribution network, and the reactive power optimization results are calculated to verify the feasibility and effectiveness of the improved algorithm.

关键词： Ant colony optimization distribution network differential evolution reactive power optimization.

Nonsolvable Groups with Three Nonlinear Irreducible Character Codegrees

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 173-178页

作者： Dongfang YANG yu ZENG Department of Mathematics Changshu Institute of TechnologyChangshu 215500JiangsuChina

For an irreducible characterχof a?nite group G,the codegree ofχis de-?ned as|G:ker(χ)|/χ(1).In this paper,the authors determine?nite nonsolvable groups with exactly three nonlinear irreducible character codegrees,... 详细信息

关键词： Character codegree Nonsolvable group

Boundedness of some integral operators and commutators on homogeneous Herz spaces with three variable exponents

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Frontiers of Mathematics in China 2021年第1期16卷 211-237页

作者： Xia yu Zongguang LIU School of Sciences China University of Mining and TechnologyBeijing 100083China

We obtain the boundedness of some integral operators and commutators on homogeneous Herz spaces with three variable exponents K^(˙α(⋅))_(p(⋅),q(⋅)),such as some sublinear operators,the fractional integral and its co... 详细信息

关键词： Sublinear operator fractional integral commutator homogeneous Herz space variable exponent

SIGNIFICANCE OF PRE-S2 PROTEIN AND ITS ANTIBODY IN CHILDREN WITH HBV INFECTIONS

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中华医学杂志(英文版) 1991年第2期104卷 124-127页

作者： M X Zou M Y yu H F Zhang J q Huang J M Chen 302 Hospital of PLA Beijing.

Pre-S2 protein and its antibody were detected in 130 children with hepatitis B virus (HBV) infection and 30 with T6 hepatitis B (HB) vaccination. The resuits showed that pre-S2 was positive in most chronic persistent hepatitis (CPH) and chronic active hepatitis(CAH) patients, while anti-pre-S2 was positive in only 8% (2/92 cases) and 11.5% (3/26 cases) respectively. The positive rate of anti-pre-S2 was 78.9%(15/19 cases) in cases at the convalescent stage of acute hepatitis B, 91.7% (55/60 cases) in eases with T6 HB vaccination and 83.3%(25.30 cases) in naturally acquired anti-HBs children, while pre-S2 was not noted. Anti-pre-S2 was negatively related to ALT and positively to anti-HBs (P<0.01). The positive relation of pre-S2 to HBsAg was observed. These results suggest that pre-S2 could be a marker for HBV infection, and anti-pre-S2 may indicate a favourable prognosis of HBV infection. There was no correlation between anti-pre-S2 and pathogenic damages induced by HBV.

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Formation of intermetallic phases in unrefined and refined AA6082 Al alloys investigated by using SEM-based ultramicrotomy tomography

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Journal of Materials Science & Technology 2022年第25期120卷 118-128页

作者： J.M.yu T.Hashimoto H.T.Li N.Wanderka Z.Zhang C.Cai X.L.Zhong J.qin q.P.Dong H.Nagaumi X.N.Wang Shagang School of Iron and Steel and High-Performance Metal Structural Materials Research Institute Soochow UniversitySuzhou 215137China School of Materials The University of ManchesterSackville StreetManchester M139PLUK Chinalco Materials Application Research Institute Co.Ltd. Beijing 102200China Helmholtz-Zentrum Berlin Für Materialien und Energie Hahn-Meitner-Platz 1Berlin 14109Germany Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

The spatial arrangement,distribution and morphology of Fe-bearing intermetallics in AA6082 alloys depends on the manufacturing process of the alloy and thus influences the macroscopic ***,the microstructure of a near industrial scale casting AA6082 Al alloy fabricated by:(a)direct chill casting,(b)Al-5 Ti-1 B grain refiner addition and(c)intensive melt shearing has been investigated by threedimensional visualization using SEM-based serial ultra microtomy *** formation sequence of phases in AA6082 alloys is generally categorized into four stages:formation ofα-Al grains,Fe-bearing intermetallics,Mg_(2)Si phase,and eutectic *** of three-dimensional visualization of the microstructure indicated that TiBparticles not only could nucleate Fe-bearingβ-intermetallics,but also could provide substrate for the formation of Fe-bearingα-intermetallics and Mg_(2)Si.A further deep analysis reveals that the essential condition for the formation of secondary phases such as Fe-bearing intermetallics and Mg_(2)Si phase is the build-up of a supersaturated solute front at theα-Al solid-liquid interface irrespective of the specific nucleation *** addition,the results indicate that grain refinement processing causes the severe interconnectivity of Fe-bearingα-***,the intensive melt shearing is a better manufacturing process because the intermetallics are more evenly distributed and refined than with the addition of the grain refiner,thereby improving the properties of the alloy.

关键词： Al-Si-Mg alloy Grain refinement Al-Fe-Si intermetallic phase Tomography Ultramicrotomy Mg2Si

Optical properties of conductive silver-nanowire films with different nanowire lengths

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Nano Research 2017年第11期10卷 3706-3714页

作者： Xiaoming yu Xuan yu Jianjun Zhang Liqiao Chen yunqian Long Dekun Zhang Innovation Application Institute Zhejiang Ocean University Zhoushan 316004 China College of Electronic Information and Optical Engineering Nankai University Tianjin 300071 China

Transparent electrodes made of silver nanowires （Ag NWs） exhibit a higher flexibility than conventional indium tin oxide *** this reason,Ag NWs may find applications in future flexible electronic and optoelectronic ***,different optoelectronic devices have different specific requirements for Ag *** example,the optical transmittance haze is an important but rarely studied aspect of Ag NW *** this study,the optical transmittance and optical scattering of long （5-50 μm,L-NWs） and short （1-20 μm,S-NWs） Ag NW films were *** L-NWs exhibited better optical transmission than the S-NWs,whereas the S-NWs exhibited better light-scattering properties than the *** results indicate that the L-NWs are suitable for touch-screen displays,whereas the S-NWs are better suited as transparent conductive films for solar *** analyzed the scattering ratio of forward-scattered light to backscattered light for both the L-NWs and S-NWs and discovered that the mesh size affected the scattering *** longer wavelengths,a larger mesh yielded a higher backscattering ratio,whereas a smaller mesh yielded a lower backscattering *** formulated an equation for calculating the reflection haze using the total reflection （Ag NWs/glass）,R and the reflection of glass,*** reflection haze of the S-NWs and L-NWs exhibited different trends in the visible-near-infrared *** omnidirectional scattering model for the Ag NWs was used to evaluate the Ag NW scattering *** results of this study have great significance for the evaluation of the performance of Ag NWs in optoelectronic devices.

关键词： transparent electrode silver nanowires transmittance haze factor forward scattering and backscattering reflection-haze factor

A scenario for high accuracy τ mass measurement at BEPC-Ⅱ

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Chinese Physics C 2012年第7期36卷 573-577页

作者： M. N. Achasov V. E. Blinov 蔡啸傅成栋 F. A. Harris q. Liu 莫晓虎 N. yu. Muchnoi I. B. Nikolaev 秦庆 A. G. Shamov K. yu. Todyshev 王贻芳张建勇 Budker Institute of Nuclear Physics Siberian Branch of the Russian Academy of Sciences11 Lavrentyev Novosibirsk 630090 Russia Institute of High Energy Physics Chinese Academy of Sciences University of Hawaii HonoluluHI 96822 USA

Scenarios for the τ mass measurement at the upgraded Beijing Electron-Positron Collider （BEPC- II ） are studied. A nested minimization procedure is used to optimize the data taking plan. It is found that by using five energy points with the total integrated luminosity of 100 pb-1, the τ mass can be determined with a statistical error of 50 keV.

关键词： τ mass scan optimization uncertainty

Electron mass enhancement and magnetic phase separation near the Mott transition in double-layer ruthenates

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Frontiers of physics 2018年第4期13卷 159-165页

作者： Jin Peng X. M. Gu G. T. Zhou W. Wang J. Y. Liu yu Wang Z. q. Mao X. S. Wu Shuai Dong School of Physics Southeast University Nanjing 211189 China Collaborative Innovation Center of Advanced Microstrucutres Lab of Solid State Microstructures School of Physics Nanjing University Nanjing 210093 China Department of Physics and Engineering Physics Tulane University New Orleans LA 70118 USA

We present a detailed investigation of the specific heat of Ca3（Ru1-xMx）2O7 （M = Ti, Fe, Mn） single crystals. Depending on the dopant and doping level, three distinct regions are present： a quasi- two-dimensional metallic state with antiferromagnetic （AFM） order formed by ferromagnetic bilayers （AFM-b）, a Mott insulating state with G-type AFM order （G-AFM）, and a localized state with a mixed AFM-b and G-AFM phase. Our specific heat data provide deep insights into the Mort transitions induced by Ti and Mn doping. We observed not only an anomalous large mass enhancement, but also an additional term in the specific heat, i.e., C ∝ T2, in the localized region. The C ∝ T2 term is most likely due to long-wavelength excitations with both FM and AFM components. A decrease in the Debye temperature is observed in the G-type AFM region, indicating lattice softening associated with the Mott transition.

关键词： specific heat ruthenates Mort insulator phase separation

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

quantification of driving factors on NDVI in oasis-desert ecotone using geographical detector method

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Journal of Mountain Science 2019年第11期16卷 2615-2624页

作者： ZHANG yu ZHANG Ke-cun AN Zhi-shan yu Yan-ping Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesCASLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Within oasis-desert ecotone regions,the normalized difference vegetation index(NDVI)is an important parameter for evaluating the growth of *** accurate quantitative study between NDVI and environmental and anthropogenic factors is critical for understand the driving factors of vegetation growth in oasis-desert *** 2016,four periods Landsat 8 OLI_TIRS images,relevant climatological parameters data(air temperature,air relative humidity,wind velocity and accumulated temperature),land cover type data and soil data were selected as *** order to quantify the explanatory power for NDVI spatial and temporal distribution in the southern edge of Dunhuang City and northern side of the Mingsha Mountain,the geographical detector model was used to explain the potential influences of factors versus the spatial distribution of NDVI,and each explanatory variable's relative importance can be *** factor detector results disclose that the spatial distribution of NDVI is primarily dominated by land cover *** risk detector results show that,high NDVI region is located within *** mean value of NDVI displays an increase and then decrease trend with air temperature *** the increase of wind velocity and decrease of air relative humidity,the NDVI value shows a decrease *** interactive q values between the two factors are higher than any q value of separated *** also indicate that the strongest interactive effects of NDVI are different in distinct ***,anthropogenic activity is more important than environmental factors on NDVI in oasis-desert *** also demonstrate that air relative humidity rather than air temperature have played a greater role in NDVI spatial distribution.

关键词： Influence factors Normalized difference vegetation index Geographical detector Oasis-desert ecotone