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Performance evaluation and optimization design of photoelectric pyrometer detection optical system

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Defence Technology（防务技术） 2020年第2期16卷 401-407页

作者： Xue-yan Han ke-wei Huan Shan-ju sheng School of Science Changchun University of Science and TechnologyChangchun 130022China

The measurement and control of high temperature play very important roles in national defense,military,scientific experiments,industrial and agricultural *** pyrometer is one of the important radiation thermometers for non-contact temperature *** has an important application in the field of high temperature measurement,and its performance directly affects the accuracy of temperature *** improving the design of the detection optical system of the photoelectric pyrometer,the imaging performance of the photoelectric pyrometer can be improved effectively,and the temperature measurement accuracy can be *** this paper,the temperature measurement principle of photoelectric pyrometer,the wo rking principle of the detection optical system and the composition of the system are *** optical components that affect the imaging of the optical system of the photoelectric pyrometer are *** optical pyrometer detection optical system is simulated by ZEMAX software,based on the analysis results,the Modulation Transfer Function(MTF)and the spot Diagram are used as the main evaluation criteria to optimize the design of the objective lens of the photoelectric pyrometer detection optical *** imaging performance of the photoelectric pyrometer detection optical system and the accuracy of temperature measurement of the photoelectric pyrometer are improved by optimization design of the detection optical system.

关键词： Photoelectric pyrometer Detection optical system ZEMAX MTF Spot diagram

Effect of Ag and Ni on the melting point and solderability of SnSbCu solder alloys

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 691-695页

作者： Yan-fu Yan Yan-sheng wang Li-fang Feng ke-xing Song Jiu-ba Wen Henan key Laboratory of Advanced Non-ferrous Metals Luoyang 471003 China Architecture and Civil Engineering Institute Henan University of Science and Technology Luoyang 471003 China

To improve the properties of Sn10Sb8Cu solder alloy, two new solders （SnSbCuAg and SnSbCuNi） were formed by adding small amounts of Ag or Ni into the solder alloy. The results show that the melting point of the SnSbCuAg solder alloy decreases by 14.1℃ and the spreading area increases by 16.5% compared to the matrix solder. The melting point of the SnSbCuNi solder alloy decreases by 5.4℃ and the spreading area is slightly less than that of the matrix solder. Microstructure analysis shows that adding trace Ag makes the melting point decline due to the dispersed distribution of SnAg phase with low melting point. Adding trace Ni, Cu6Sn5 and （Cu, Ni）6Sn5 with polyhedron shape on the copper substrate can be easily seen in the SnSbCuNi solder alloy, which makes the viscosity of the melting solder increase and the spreading property of the solder decline.

关键词： solder alloy Ag Ni melting point solderability

Constructions of vector output Boolean functions with high generalized nonlinearity

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 77-81页

作者： ke Pin-hui ZHANG sheng-yuan key Laboratory of Network Security and Cryptology Fujian Normal UniversityFujian 350007 China

Carlet et al. recently introduced generalized nonlinearity to measure the ability to resist the improved correlation attack of a vector output Boolean function. This article presents a construction of vector output Boolean fimctions with high generalized nonlinearity using the e-biased sample space. The relation between the resilient order and generalized nonlinearity is also discussed.

关键词： Boolean functions correlation attack generalizednonlinearity almost resilient functions

A new lathyrane diterpene glycoside from Euphorbia helioscopia L.

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Chinese Chemical Letters 2010年第2期21卷 191-193页

作者： Feng, Wei sheng Gao, Li Zheng, Xiao ke wang, Yan Zhi Chen, Hui Henan Coll Tradit Chinese Med Zhengzhou 450008 Peoples R China Chinese Acad Med Sci Beijing 100050 Peoples R China Peking Union Med Coll Inst Mat Med Beijing 100050 Peoples R China

A new lathyrane diterpene glycoside,named 3β,7β,15β-trihydroxy-14-oxolathyra-5E,12E-dienyl-16-O-β-D-glucopyranoside, was isolated from Euphorbia helioscopia *** structure was established by spectroscopic technique... 详细信息

关键词： Euphorbia Euphorbia helioscopia L. Lathyrane diterpene glycoside

A Categorification of the Boson Oscillator

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Communications in Theoretical Physics 2012年第1期57卷 34-40页

作者： LIN Bing-sheng WU ke School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

In this paper,we investigate the categorical description of the boson *** on the categories constructed by Khovanov,we introduce a categorification of the Fock states and the corresponding inner product of these *** find that there are two different categorical definitions of the inner product of the Fock *** two definitions are consistent with each other,and the decategorification results also coincide with those in conventional quantum *** also find that there are some interesting properties of the 2-morphisms which relate to the inner product of the states.

关键词： categorification Boson oscillator Fock state Heisenberg algebra

On the Phase Transitions of (k,q)-SAT

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 605-610页

作者： Jun LIU Zong-sheng GAO ke XU State key Laboratory of Software Development Environment Beihang University LMIB and School of Mathematics and Systems Science Beihang University

Call a sequence of k Boolean variables or their negations a k-tuple. For a set V of n Boolean variables, let Tk（V） denote the set of all 2^kn^k possible k-tuples on V. Randomly generate a set C of k-tuples by including every k-tuple in Tk（V） independently with probability p, and let Q be a given set of q ＂bad＂ tuple assignments. An instance I = （C, Q） is called satisfiable if there exists an assignment that does not set any of the k-tuples in C to a bad tupie assignment in Q. Suppose that θ, q 〉 0 are fixed and ε=ε（n）〉 0 be such in 2 that ε Inn/ In Inn → ∞. Let k ≥ （1 ＋ θ） log2 n and let p0 = ln2/qn^k-1. We prove thatlim∞ P[I issatisfiable] ={1,p≤（1-ε）p0, 0,p≥（1＋ε）p0.

关键词： constraint satisfaction phase transition the second moment method

Exoskeleton active assistance strategy for human muscle activation reduction during linear and circular walking

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Advances in Manufacturing 2024年第3期12卷 484-496页

作者： Wen-Tao sheng ke-Yao Liang Hai-Bin Tang School of Intelligent Manufacturing Nanjing University of Science and TechnologyNanjing210094People’s Republic of China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150001People’s Republic of China

The exoskeleton is employed to assist humans in various domains including military missions,rehabilitation,industrial operation,and activities of daily living(ADLs).Walking is a fundamental ADL,and exoskeletons are capable of reducing the activation and metabolism of lower extremity muscles through active assistance during *** improve the performance of active assistance strategy,this article proposes a framework using an active hip ***,it correlates to an already established Bayesian-based human gait recognition algorithm,with a particular focus on linear and circular walking within industrial and ADL *** theorizing this strategy for exoskeletons,this study further reveals,in part,the activation characteristics of human hip muscles for the instruction and regulation of active assistance duration and onset *** proposed active assistance strategy provides new insights for enhancing the performance of assistive robots and facilitating human robot interaction within the context of ADLs.

关键词： Human-robot interaction Hip exoskeleton Muscle activation Walking assistance

Interregional compensation for farmland protection:From the perspective of farmland allocation optimization

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Journal of Geographical Sciences 2024年第7期34卷 1437-1454页

作者： YANG Bohan sheng Siyu SHANGGUAN Ziheng ke Xinli School of Public Administration Central China Normal UniversityWuhan430079China School of Business Hubei UniversityWuhan430000China College of Public Administration Huazhong Agricultural UniversityWuhan430070China

Interregional compensation for farmland protection(IRCFP)is a policy instrument for encouraging farmland protection through interregional fiscal transfer *** practices and studies on IRCFP have generally determined the payers and recipients of compensation based on the present distribution of farmland,and the compensation standards did not combine farmland development right value with farmland deficit and surplus,resulting in insignificant effects on farmland protection and even policy ***,in this study,we proposed an interregional compensation mechanism for farmland protection based on farmland allocation optimization by considering 31 provincial-level regions in *** results showed that(1)the determination of farmland surplus or deficit areas based on farmland allocation optimization met the regional construction land demand from the perspective of achieving food security.(2)The combination of the compensation value standard and cropland deficit and surplus had a positive effect on farmland protection.(3)Interregional compensation for farmland protection based on farmland allocation optimization can coordinate economic development,farmland protection,and ecological ***,we discussed the rationality of interregional compensation for farmland protection based on farmland allocation optimization and designed the operation mechanism of IRCFP.

关键词： interregional compensation farmland allocation optimization farmland protection land development rights China

Vertical grain-size trend of mouth bar in lacustrine fan delta:Flume experiments

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Petroleum Science 2022年第5期19卷 1964-1977页

作者： ke Zhang sheng-He Wu Jun-Jie wang Yun-Jie Xu Zhen-Hua Xu Jia-Jia Zhang State key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China School of Geosciences Yangtze UniversityWuhanHubei 430100China

Field observational previously indicated a mouth bar of a fan delta could exhibit a fining-or coarseningupward trend,which bring a new challenge to the identification of mouth bar in subsurface studies due to the lack of morphological *** studies have indicated that effluent behavior in rivermouth system can affect the vertical grain-size trend of mouth bar,but the drivers and magnitude of this phenomenon are not *** conducted flume experiments to investigate the mechanism and controlling factors of vertical grain-size trend of mouth *** with a steeper slope of the substrate layer,greater discharge,higher sediment/water ratio,and coarser sediment induced a finingupward trend of mouth bar,because the effluent was dominated by strong *** bar in the experiment with a gentler slope of the substrate layer,smaller discharge,lower sediment/water ratio,and finer sediment exhibited a coarsening-upward trend dominated by the friction-dominated *** relationship between the vertical grain-size trend of mouth bar and the gradients of foreset bedding in small-scale flume models and the cut-off of 15°-18°are applicable in natural *** depositional setting to infer depositional process in river-mouth system and analyzing the plane geometry of sandbodies are two steps in the interpretation of ancient fan deltaic rock record.

关键词： Mouth bar Vertical grain-size trend Effluent behavior Inertia Bed friction