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空间温室灯组件的自适应控制

深空探测学报（中英文） 2021年第4期8卷 433-444页

作者： Y.berkovich A.Buryak O.Ochkov O.Perevedentsev S.Smolyanina 俄罗斯国家科学院生物医学问题研究所俄罗斯莫斯科123007

到目前为止,基于发光二极管(Light Emitting Diodes-based,LED)的照明器被广泛用于除自然光之外的温室植物照明,以及没有自然光的植物工厂。优化人工光照参数,如日光照积分和不同光谱成分的比值,可以显著降低生物生命支持系统(Biologica... 详细信息

到目前为止,基于发光二极管(Light Emitting Diodes-based,LED)的照明器被广泛用于除自然光之外的温室植物照明,以及没有自然光的植物工厂。优化人工光照参数,如日光照积分和不同光谱成分的比值,可以显著降低生物生命支持系统(Biological Life Support Systems,BLSS)包括空间温室(Space Greenhouses,SG)中光栽培作物的生产成本。然而,由于缺乏关于窄带辐射引起的生理效应的信息,以及数学描述植物作物对LED照明参数变化的反应的复杂性,LED照明系统的优化一直受到限制。在人工照明的条件下,作物生产者通常力图建立一个恒定于整个生长季节的最佳光照制度。然而,有实验数据表明,随着植物年龄的增加,作物对光照制度的要求会发生变化。基于生物反馈的自适应搜索优化方法是改进作物LED照明参数的潜在途径。描述了建立于生物医学问题研究所(莫斯科,俄罗斯)用于大白菜栽培的基于红色和白色LED光源的自适应照明系统(Adaptive Lighting System,ALS)。其自适应控制程序实现了对实时支持最佳植物生长特性的当前照明参数的连续自动搜索。ALS包括一个封闭的生长室,带有基于红色和白色LED灯的光组件(Light Assembly,LA),并配有一个气体二氧化碳分析仪(Gas CO2 Analyzer,GA)。每一种发光二极管的光子通量密度(Photosynthetic photon flux density,PPFD)由微处理器(microProcessor,mP)中的程序相互独立控制。红外GA定期测量生长室内由作物的表观光合作用(Visible Photosynthesis,VF)引起的CO2浓度下降。mP接收来自遗传算法输出的信号,并计算作物的光合速率,以及当前的光照质量功能值。然后程序比较在当前时刻和上一步得到的优化准则值,并根据选择算法和LED电源电流的新值计算梯度的方向,使优化准则的值朝着正确的方向变化。此外,供电单元为各类型的LED链提供电流,LA变换植物的照明模式。我们用等效系统质量(Equivalent System mass,ESm)的最小比值作为SG照明质量的标准,该值取决于植物的照明状况。SG单位种植面积等效质量和SG单位耗电量的成本系数在很大程度上取决于航天器设计和空间探测方案。根据文献,基于光子通量密度和作物光效率的等效系统质量估计值已经在一艘用于长期使用的月球基地的空间探测场景,有4名宇航员的航天器中计算出来。为了寻找植物生长过程中的当前最优光照参数,采用了梯度和单纯形算法。采用入射于作物茎尖的整体光子通量密度水平和红色与白色光通量密度的比值(因子X1和X2)作为优化因子。X1的调节范围为200~700μmol/(m2·s),X2的调节范围为0~1.5。通过对照实验比较使用ALS或最佳恒定LED照明时的等效系统质量来评估自适应照明系统的效果。根据月球基地考察的最小ESm准则(1),在植物生长第14~24 d期间对大白菜作物光照进行自适应优化,使得SG等效质量节约了14.9%。具有其它优化准则的类似系统可用于陆生植物工厂。

关键词：空间温室自适应优化作物生产力表观光合作用发光二极管光谱组成

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Some Technical Solutions for Environmental Protection System during Accidents at Nuclear Power Plants

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World Journal of Engineering and Technology 2017年第4期5卷 1-11页

作者： Sergey A. kulyukhin Igor’ A. Rumer Viktor m. berkovich Gennadii S. Taranov Ivan V. Yagodkin Viktor P. Osipov Sergey S. Skvortsov Leo N. Falkovskii Frumkin’ Institute of Physical Chemistry and Electrochemistry Russian Academy of Sciences (IPCE RAS) Moscow Russia Institute “Atomenergoproekt” (AEP) Moscow Russia Institute of Physics and Power Engineering (IPPE) Obninsk Russia All-Russian Research Institute of Atomic machine-Building (VNIIAm) Moscow Russia

The paper reports some technical solutions, which suggested or used for increasing of environmental protection during accidents at NPPs. For NNPs with two protective shells and pressure release system such as WWER-1000 a comprehensive, passive-mode environmental protection system of decontamination of the radioactive steam-air mixture from the containment and the intercontainment area was suggested. This system includes the “wet” stage (scrubbers, etc.), the “dry” stage (sorption module), and also an ejector, which in a passive mode is capable of solving the multi-purpose task of decontamination of the air-steam mixture. For WWER-440/230 NPPs three protection levels: 1) a jet-vortex condenser;2) the spray system;3) a sorption module were suggested and installed. For modern designs of new generation NPPs, which do not provide for pressure release systems, a new passive filtering system together with the passive heat-removal system, which can be used during severe accidents in case all power supply units become unavailable, was proposed and after modernization was installed at the kudankulam NPP (India).

关键词： Nuclear Power Plants Severe Accident Environment Protection Radioactive Steam-Air Phase

mICROBRIDGE TESTING OF YOUNG'S mODULUS AND RESIDUAL STRESS OF NICkEL FILm ELECTROPLATED ON SILICON WAFER

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Acta metallurgica Sinica(English Letters) 2004年第3期17卷 247-254页

作者： Y.Zhou C.S.Yang J.A. Chen G.F. Ding L. Wang m.J Wang Y.m Zhang T.H Zhang key Laboratory for Thin Film and microfabrication of ministry of Education Research Institute of Micro/Nanometer Science and Technology Shanghai Jiaotong University Shanghai 200030 China State key Laboratory of Nonlinear mechanics (LNm) Institute of Mechanics The Chinese Academy of Sciences Beijing 100080 China.

microbridge testing is used to measure the Young's modulus and residual stresses of metallic *** film microbridges with widths of several hundred microns are fabricated by microelectromechanical *** order to measure the mechanical properties of nickel film microbridges,special shaft structure is designed to solve the problem of getting the load--deflection curves of metal film microbridge by Nanoin--denter XP system with normal berkovich *** analysis of the micro--bridge load--deflection curve is proposed to evaluate the Young's modulus and residual stress of the films *** calculated results based on the experimental measurements show that the average Young's modulus and residual stress are around 190GPa and 175mPa respectively,while the Young's modulus measured by Nano-hardness method on nickel film with silicon substrate is 186.8±7.34GPa.

关键词： nickel film microbridge mEmS mechanical property loadeflection measurement

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A Nanoindentation Study on the Rheological Behaviour of Bituminous Binders

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武汉理工大学学报 2010年第17期32卷 47-50页

作者： LIU G VAN DE VEN m WU S P YU J Y mOLENAAR A Faculty of Civil Engineering and Geosciences Delft University of TechnologyP.O. Box 50482600 GA Delftthe Netherlands key Laboratory of Silicate materials Science and Engineering of ministry of Education Wuhan University of TechnologyWuhan 430070China

This paper reports the nanoindentation results of three bituminous binders,C-Fix,and standard penetration grade 40/60 bitumen and organo-montmorillonite (Omt) modified bitumen. Under a load applied by the berkovich diamond indenter,a loading and unloading history was recorded and the load-displacement curve was analyzed as a function of time. The software can directly give an output value of the modulus for C-Fix. However the result was dependent on the loading history. Due to increasing viscoelastic behaviour,the output value of the modulus for base bitumen was always negative,even with a very short unloading time. In conclusion,the modulus calculated by the software was not suitable for the bituminous binders due to their time-dependence. The nanoindentation curve during the loading phase of bitumen could be described by the adopted creep model. The results indicated that the Omt modified bitumen showed a high creep resistance than the base bitumen due to the Omt's reinforcement.

关键词： nanoindentation bitumen viscoelasticity creep

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