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Effect of vanadium on dynamic continuous cooling transformation behavior of medium-carbon forging steels

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Journal of Iron and Steel Research International 2017年第6期24卷 641-648页

作者： Wei-jun Hui Na xiao xiao-li Zhao yong-jian Zhang Yu-feng Wu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing 100044 China Faculty of Materials Science and Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China

Dynamic continuous cooling transformation （CCT） behavior of medium-carbon forging steels microalloyed with different V contents up to 0.29% was investigated by means of dilatometric measurement, microstructural observation and hardness measurement. The re- sults showed that the dynamic CCT diagrams were similar and the main difference was that the fields of the transformation products were shifted to the right side of the diagrams with the increase of V content, and this effect was more noticeable with an addition of 0. 290/00 V. The At1 and At3 temperatures showed increasing trends with increasing V content, while the critical cooling rates decreased with increasing V content. The increase of V content re- sulted in significant increase of hardness and this tendency was enhanced with increasing cooling rate until the formation of acicular ferrite （AF）. A promising approach of remark- ably improving the toughness of ferritic-pearlitic medium-carbon forging steels with suit- able V addition and the introduction of AF without notable penalty on its strength level was suggested.

关键词： Dynamic CCT diagramVanadiumMicroalloyed steelMierostruetureHardness

A 3-channel CCD photometer at the Xinglong Observatory

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Research in Astronomy and Astrophysics 2013年第2期13卷 239-252页

作者： yong-Na Mao xiao-Meng Lu jian-Feng Wang xiao-Jun jiang National Astronomical Observatories Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences

We describe the design and construction of a new rapid 3-channel CCD photometer, dedicated to simultaneous multicolor photometric observations of rapidly variable objects. This photometer is equipped on the 1-meter telescope at the Xinglong Observatory. It allows simultaneous imaging within fields of view of 18.81′×18.8′, 18.2′×17.6′ and 9.2′×9.2′ in the Sloan Digital Sky Survey＇s g′, r′ and i′ bands, respectively. The results of its calibration and performance are reported.

关键词： instrumentation photometers-- techniques photometric-- stars novae

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爆炸切割网络传爆中的间隙与角度效应

火工品 2025年第1期 37-43页

作者：周晓鹏姜勇袁航中国船舶集团有限公司第七一三研究所河南郑州450015 河南省水下智能装备重点实验室河南郑州450015

为研究爆炸切割网络中传爆节点处传爆能力的关键影响因素,通过改变切割索对传爆药柱的传爆间隙进行了平板传爆试验,将试验结果结合仿真分析确定了JO-11C传爆药柱的仿真材料参数,并进一步分析了传播角度对传爆能力的影响。研究结果表明:... 详细信息

为研究爆炸切割网络中传爆节点处传爆能力的关键影响因素,通过改变切割索对传爆药柱的传爆间隙进行了平板传爆试验,将试验结果结合仿真分析确定了JO-11C传爆药柱的仿真材料参数,并进一步分析了传播角度对传爆能力的影响。研究结果表明:随着传爆间隙的增加,传爆能力下降,切割索对传爆药柱的最大传爆间隙区间为2.0~2.5 mm;同时,传爆角度的增大能够显著提高传爆能力。本研究为爆炸切割网络的传爆性能研究以及提高武器系统的可靠性提供了参考。

关键词：爆炸切割网络传爆间隙传爆角度传爆药柱仿真分析

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Temperature-Dependent Photoluminescence of Silicon Nanoporous Pillar Array

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Chinese Physics Letters 2014年第4期31卷 170-173页

作者： LI yong WANG xiao-Bo FAN Zhi-Qiang LI Xin-jian Department of Physics and Laboratory of Material Physics Zhengzhou University Zhengzhou 450052 Department of Pt2ysies and Solar Energy Research Center Pingdingshan University Pingdingshau 467000 Department of Physics Anyang Normal University Anyang 455000

Silicon nanoporous pillar array （Si-NPA） is a micron-nanometer hierarchical structure which might be used as functional substrates for constructing optoelectronic nanodevices. This makes understanding the photolumines- cence （PL） from Si-NPA important. We measure the PL of Si-NPA in the range of 11-300K. By analyzing the evolution of the peak energy and intensity with temperature, the ultraviolet, blue, orange and red PL bands from Si-NPA are attributed to the radiative recombination through the deep-levels in silicon oxide, oxygen-related defect states in silicon nanocrystallites （nc-Si）, band-to-band transition within nc-Si, and surface/interface states of nc-Si or between nc-Si and SiOx, respectively. At least two non-radiative recombination processes, which are activated at different temperature ranges, are proposed for the PL intensity variation with temperature. These results might provide strong foundations for designing and constructing optoelectronic devices based on silicon nanostruetures.

关键词： PHOTOLUMINESCENCE NANOPOROUS materials NANOSILICON OPTOELECTRONIC devices FIELD emission cathodes

An object correlation and maneuver detection approach for space surveillance

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Research in Astronomy and Astrophysics 2012年第10期12卷 1402-1416页

作者： jian Huang Wei-Dong Hu Qin xin xiao-yong Du ATR Key Lab. College of Electronic Science and Engineering National University of DefenseTechnology Changsha 410073 China Faculty of Science and Technology University of the Faroe Islands Torshavn FO100 FaroeIslands

Object correlation and maneuver detection are persistent problems in space surveillance and maintenance of a space object catalog. We integrate these two prob- lems into one interrelated problem, and consider them simultaneously under a sce- nario where space objects only perform a single in-track orbital maneuver during the time intervals between observations. We mathematically formulate this integrated sce- nario as a maximum a posteriori （MAP） estimation. In this work, we propose a novel approach to solve the MAP estimation. More precisely, the corresponding posterior probability of an orbital maneuver and a joint association event can be approximated by the Joint Probabilistic Data Association （JPDA） algorithm. Subsequently, the ma- neuvering parameters are estimated by optimally solving the constrained non-linear least squares iterative process based on the second-order cone programming （SOCP） algorithm. The desired solution is derived according to the MAP criterions. The per- formance and advantages of the proposed approach have been shown by both theoret- ical analysis and simulation results. We hope that our work will stimulate future work on space surveillance and maintenance of a space object catalog.

关键词： celestial mechanics -- methods: analytical -- techniques: miscellaneous-- surveys

SOFC temperature evaluation based on an adaptive fuzzy controller

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 688-694页

作者： xiao-juan WU Xin-jian ZHU Guang-yi CAO Heng-yong TU Institute of Fuel Cell Department of Automation Shanghai Jiao Tong University Shanghai 200030 China

The operating temperature of a solid oxide fuel cell (SOFC) stack is a very important parameter to be controlled, which impacts the performance of the SOFC due to thermal cycling. In this paper, an adaptive fuzzy control method based on an affine nonlinear temperature model is developed to control the temperature of the SOFC within a specified range. Fuzzy logic systems are used to approximate nonlinear functions in the SOFC system and an adaptive technique is employed to construct the controller. Compared with the traditional fuzzy and proportion-integral-derivative (PID) control, the simulation results show that the designed adaptive fuzzy control method performed much better. So it is feasible to build an adaptive fuzzy controller for temperature control of the SOFC.

关键词： Solid oxide fuel cell (SOFC) Temperature control Adaptive fuzzy controller Affine temperature model

Stray light analysis of the Xinglong 2.16-m telescope

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Research in Astronomy and Astrophysics 2020年第3期20卷 50-61页

作者： Tao-Ran Li jian-Feng Wang xiao-Ming Zhang yong Zhao jian-Feng Tian Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

An effort towards understanding the problems associated with stray light related to the Xinglong2.16-m telescope is presented to estimate the stray light performance of the telescope itself and provide a method for improving stray light *** light analysis for the 2.16-m telescope model,which consists of an onion shaped dome,telescope structure,equatorial mount and telescope optics,has been developed in two cases(1)pointing to 60?and(2)pointing to zenith,in both azimuth and elevation *** Point Source Normalized Irradiance Transmittance(PSNIT),which is generally used for assessing stray light and is uncorrelated to entrance aperture,is calculated with a series of off-axis *** shows that the PSNIT values are less than 10-7 when off-axis angles are larger than±20?.The dominant contributors to stray light(primary and secondary mirror,telescope structure and dome)are identified to guide performance *** analyses indicate that significant benefit can be realized by adding only five vanes inside the bottom portion of the secondary *** the case of pointing to zenith,the PSNIT values will decrease about 40%on average.

关键词： telescope scattering methods:data analysis

朋辈心理咨询进社区:高校“一站式”学生社区心理育人功能实践路径研究

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黑龙江高教研究 2025年第1期43卷 135-139页

作者：邢晓雪王怀勇南京工业大学江苏南京211816 上海师范大学上海200234

结合高校“一站式”学生社区综合管理模式建设提质增效工作指南,探讨朋辈咨询进入学生社区的天然耦合性,并从社会生态系统理论视角提出朋辈咨询嵌入“一站式”学生社区实现心理育人功能的多重路径选择,在微观环境中注重发挥朋辈咨询员... 详细信息

结合高校“一站式”学生社区综合管理模式建设提质增效工作指南,探讨朋辈咨询进入学生社区的天然耦合性,并从社会生态系统理论视角提出朋辈咨询嵌入“一站式”学生社区实现心理育人功能的多重路径选择,在微观环境中注重发挥朋辈咨询员的匹配优势,在中观环境中以朋辈咨询体制为抓手优化社区心理育人体系建设,在宏观环境中利用朋辈咨询资源加强常态化的“文化渗透式”心理健康教育,全方位、立体式、浸润式打通高校心理育人“最后一公里”。

关键词： “一站式”学生社区朋辈咨询心理育人社会生态系统理论

A Variable Parameter Linear Tracking Differentiator and Its Application in Large Ground-based Telescopes

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Research in Astronomy and Astrophysics 2022年第12期22卷 273-283页

作者： xiao-Xia Yang yong-Ting Deng jian-Li Wang Bin Zhang Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

This paper is concerned with the characteristics of a tracking differentiator(TD)in arranging transition process for the physical *** order to overcome disadvantages of linear TD(LTD)in practice,a novel variable parameter linear tracking differentiator(VLTD)is *** designing the speediness factor as a function of the tracking error,the VLTD can track a large range of set values with reasonable speed and *** shows that VLTD can converge to its set value under certain ***,the speed and acceleration bounds are added to the VLTD,which guarantees that the proposed transition signal really plays a transitional *** numerical simulation results emphasize necessity for adding speed and acceleration bounds to the *** comparing VLTD with the nonlinear TD(NLTD)in the simulations and experiments,VLTD can achieve almost the same performance as the NLTD while it is easier to be implemented.

关键词： methods:data analysis methods:analytical methods:numerical telescopes