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The influence of urban three-dimensional structure and building greenhouse effect on local radiation flux

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Science China Earth Sciences 2021年第11期64卷 1934-1948页

作者： renhua zhang Wenhui KUANG Shiqi YANG Zhaoliang LI Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China

Accurate measurements of the three-dimensional structure characteristics of urban buildings and their greenhouse effect are important for evaluating the impact of urbanization on the radiation energy budget and research on the urban heat island(UHI)*** decrease in evapotranspiration or the increase in sensible heat caused by urbanization is considered to be the main cause of the UHI effect,but little is known about the influence of the main factor“net radiant flux”of the urban surface heat *** this study,experimental observation and quantitative model simulation were used to find that with the increase of building surface area after urbanization,the direct solar radiation flux and net radiation flux on building surface areas changed *** order to accurately quantify the relationship between the positive and negative effects,this study puts forward the equivalent calculation principle of“aggregation element”,which is composed of a building’s sunny face and its shadow face,and the algorithm of the contribution of the area to thermal *** research clarifies the greenhouse effect of a building with walls of glass *** shows that when the difference between absorption rates of a concrete wall and grass is−0.21,the cooling effect is *** the case of concrete walls with glass windows,the difference between absorption rates of a building wall and grass is−0.11,which is also a cooling *** greenhouse effect value of a building with glass windows reduces the cooling effect value to 56%of the effect of a building with concrete *** simulation of changes in net radiant flux and flux density shows that the greenhouse effect of a 5-story building with windows yields 15.5%less cooling effect than one with concrete walls,and a 30-story building with windows reduces the cooling effect by 23.0%.The simulation results confirmed that the difference in the equivalent absorption rate of the aggregation element is the“director”of

关键词： Aggregation element algorithm Greenhouse effect of buildings with windows Net radiation flux Direct solar radiation flux Architectural shadow

On the applicability of Kirchoff's law and the principle of heat balance in thermal infrared remote sensing:A non-isothermal system

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Science China Earth Sciences 2005年第1期48卷 53-64页

作者： zhang renhua LI Zhaoliang SUN Xiaomin ZHU Zhilin WANG Weimin Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

This paper proposes a basic equation of thermal radiation interaction between surface objects on the basis of the principle of heat balance in the interface. The solution of this equation takes account of the contribution of sensible heat flux and latent heat flux more completely, compared with traditional solution for surface cooling and heating processes. By the aid of the experimental data conducted in the Xiaotangshan experimental site, Beijing, both the non-applicability of Kirchoff's law and the measurability of surface emissivity in a non-isothermal system have been highlighted. Two methods called ventilation and time-delay compensations have been proposed to reduce the error induced by change of surface temperatures of non-isothermal objects during the measurement of emissivity. Based on the solution of the basic equation, this paper has analyzed and pointed out the misunderstanding in comprehension and application of Kirchoff's law published in literature.

关键词： applicability of Kirchoff's law, heat balance, non-isothermal system.

Principles and methods for the validation of quantitative remote sensing products

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Science China Earth Sciences 2010年第5期53卷 741-751页

作者： renhua zhang Jing Tian ZhaoLiang Li HongBo Su ShaoHui Chen XinZhai Tang Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

We first discuss the relativity of "true value and homogeneity" for quantitative remote sensing products (QRSPs), and then propose the definitions of "eigenaccuracy" and "eigenhomogeneity" under practical conditions. The eigenaccuracy and eigenhomogeneity for land surface crucial parameters such as albedo, leaf area index (LAI), and surface temperature are analyzed based on a series of experiments. Secondly, we point out the differences and similarities between the scale-free phenomena of the QRSPs and the measurements of the coastline length (1-dimensional) and the curved surface area (2-dimensional). An information fractal algorithm for the QRSPs is presented. In a case study for the LAI, when the fractal dimension is 2.16, the ratio of the LAI retrieval values obtained respectively from remote sensing data of 30 m and 6 km pixel resolution can actually reach as high as 2.86 for the same 6 km pixel using the same retrieval model. Finally, we propose an operational validation method "one test and two matches" and multipoint observation when the real situation does not allow carrying out scanning measurement without gap and overlap on the ground surface.

关键词： quantitative remote sensing productions (QRSPs) validation eigenaccuracy eigenhomogeneity scale-free phenomenon information fractal dimension scaling

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机械工程类国家重点实验室安全管理实践

实验室科学 2024年第4期27卷 200-203,209页

作者：易力力陶桂宝张仁华重庆大学机械传动国家重点实验室重庆400030

由于机械工程类学科科学研究的多样性和科学实验的复杂性,实验安全在机械工程类国家重点实验室开展教学和科研活动中尤为重要。针对机械工程学科特点分析机械工程类国家重点实验室潜在的安全隐患,结合机械传动国家重点实验室安全管理过... 详细信息

由于机械工程类学科科学研究的多样性和科学实验的复杂性,实验安全在机械工程类国家重点实验室开展教学和科研活动中尤为重要。针对机械工程学科特点分析机械工程类国家重点实验室潜在的安全隐患,结合机械传动国家重点实验室安全管理过程中的实践经验,介绍了实验室安全管理的措施和实践经验,提出了机械工程类国家重点实验室安全管理方面的一些思路和方法,对加强机械工程类国家重点实验室安全管理工作具有较强的参考作用。

关键词：国家重点实验室机械工程实验室安全安全管理

The concept of effective emissivity of nonisothermal mixed pixel and its test

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Chinese Science Bulletin 2000年第9期45卷 788-795页

作者： CHEN Liangfu ZHUANG Jiali XU Xiru NIU Zheng zhang renhua XIANG Yueqing Institute of RS and CIS Peking UniversityBeijing 100871China Institute of Remote Sensing Chinese Academy of SciencesBeijing 100101China Institute of Geography Chinese Academy of SciencesBeijing 100101China

Based on two preconditions, the local thermal equilibrium is satisfied and emissivities donot change with temperature, the concept of component effective emissivity of nonisothermal mixed pixel has been put forward and then the radiant directionality model of nonisothermal mixed pixel constructed from it. Our study shows that the component effective emissivity is associated with geometric structure, optical properties of target, and viewing angle, but does not depend on the component temepratures. The component temperatures can only change the ratio of component radiance to the total radiance of the mixed-pixel. The total effective emissivity of this pixel is the complement of its directional-hemisphere reflectance. After the simulation of component effective emissivity of the discrete cones and continuous vegetation canopy (winter wheat) by the Monte Carlo method, our model of radiant directionality of nonisothermal mixed pixel have been proved by lab and field measurements.

关键词： nonisothermal mixed pixel component effective emissivity multiple scattering.

A NEW MODEL FOR ESTIMATING CROP WATER DEFICIENCY BASED ON INFRARED INFORMATION

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Science in China,Ser.B 1987年第4期30卷 413-425页

作者：张仁华 Institute of Geography Academia Sinica Beijing

Based on infrared information under the condition that crop canopy surface is not always in satura-tion, this paper presents a model for estimating the crop waer deficiency. The physical concept of themodel is clear and definite, and it is convenient to calculate the crop water stress index (F). The roleof environmental factors such as the net radiation, the windspeed, etc. played on the model and thephysical meaning of the model are expounded in this paper. The model links up Jackson’s heat balancemethod and Idso’s graphic solution method. The model was tested and verified by the data acquired fromYucheng experimental station in Shangdong Province. Throughout the wheat growing season the totalcorrelation coefficient between daily crop water stress index (F) and dai1y soil water content is -*** each growing stage, the correlation coefficients between average crop water stress index (F) inthe stages and average soil water content in the stages are, respectively, -0.91 for jointing stage, -0.99for

关键词： A NEW MODEL FOR ESTIMATING CROP WATER DEFICIENCY BASED ON INFRARED INFORMATION

Model Reference Adaptive Neural Sliding Mode control for Aero-engine

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Model Reference Adaptive Neural Sliding Mode control for Aer...

Effects of Different Carbon Sources and NaBr-KCl on Synthesis of Ti(C,N)

2012 Conference on Modelling, Identification and Control (MIC2012)

作者： Jing Ma renhua zhang Northwestern Polytechnical University

The state parameter and work state of Aero-engine in the whole flight envelope are change *** the controller should deal with parameter perturbation,disturbance and the change of external *** this paper the neural network sliding mode variable structure decoupling controller based on model reference adaptive for the aero-engine is *** neural network is used as the output of the sliding mode control,and sliding mode switching function is used as the neural network *** weight of RBF network is adjusted adaptively by the error between reference model output and actual *** results of simulation show that Model Reference Adaptive Neural Sliding Mode Controller(MRANBSMC) has a good control effect in the whole flight *** eliminates the chattering phenomenon effectively and decouples well,which has a good robustness and control tracking performance in the disturbance and parameter perturbation.

关键词： aero-engine Model Reference Adaptive Sliding Mode variable structure decoupling

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China's Refractories 2008年第4期17卷 5-10页

作者： CHEN Xilai LI Yuanbing zhang renhua LI Yawei LI Jun The Hubei Province Key Lab of Ceramics and Refractories Wuhan University of Science ＆ Technology Wuhan 430081 China Hankou Electric Power Equipment Works Wuhan 430035 China

Ti（ C, N） was synthesized with the starting materials of 76. 9% titania white and 23. 1% carbon black （graphite or activated carbon ）, or 40% titania white and 60% amylum, with or without 10% NaBr - KCl, dry moulding and carbon embedded firing at i 300 ℃ and 1 400 ℃ for 3 h, respectively. Phase composition and microstructure of the synthesized Ti （C, N） were analyzed by XRD, SEM and EPMA. Effects of different carbon sources and NaBr-KCl on the synthesis of Ti（ C, N） were investigated. The results show that：（1） Ti （C, N） can be synthesized by using carbon black, graphite, activated carbon or amylum as carbon source separately; （2） Additive NaBr - KCl is more favorable for accelerating the carbothermal reduction reaction using carbon black or amylum as carbon source; （3） In the presence of NaBr - KCl, particle size of the synthesized Ti（ C, N） is 5 -8μm using carbon black as carbon source fired at 1 300 ℃ for 3 h, while that is only 1 - 3 μm using graphite, activated carbon or amylum fired at 1 400 ℃ for 3 h.

关键词： Titanium carbonitride Sodium bromide -potassium chloride molten salt Carbon source Carbo-thermal reduction method

An operational two-layer remote sensing model to estimate surface flux in regional scale: Physical background

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Science China Earth Sciences 2005年第Z1期48卷 225-244页

作者： zhang renhua SUN Xiaomin WANG Weimin XU Jinping ZHU Zhilin TIAN Jing Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Based on the improved interaction mechanism of two-layer model, this paper proposed Pixel Component Arranging and Comparing Algorithm (PCACA) and theoretically positioning algorithm, estimated the true temperature of mixed pixel in four extreme points in combination with the measurements of dry and wet points in calibration fields and improved the reliability of positioning dry and wet line. A new two-layer energy-separation algorithm was proposed,which was simple and direct without resistance network parameters for each pixel. We also proposed a new thought about the effect of advection. The albedo of mixed pixel was also separated with PCACA. In combination with two-layer energy-separation algorithm, the net radiation of mixed pixel was separated to overcome the uncertainty of conventional energy-separation algorithm using Beer's Law. Through the validation of retrieval result, this method is proved to be feasible and operational. At the same time, the uncertainty of this algorithm was objectively analyzed.

关键词： two-layer remote sensing model of surface flux in regional scale, PCACA, layered energy-separation algo-rithm.