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基于新距离测度的直觉模糊VIKOR多属性决策方法

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系统工程与电子技术 2019年第11期41卷 2524-2532页

作者：汪汝根李为民罗骁吕诚中空军工程大学研究生院

针对属性与决策者权重未知且方案属性值为直觉模糊数的多属性决策问题,并充分考虑直觉模糊环境下信息波动性与不具体性,提出了一种基于新的直觉模糊距离测度和多准则妥协解排序(VlseKriterijumska optimizacija I kompromisno resenje,V... 详细信息

针对属性与决策者权重未知且方案属性值为直觉模糊数的多属性决策问题,并充分考虑直觉模糊环境下信息波动性与不具体性,提出了一种基于新的直觉模糊距离测度和多准则妥协解排序(VlseKriterijumska optimizacija I kompromisno resenje,VIKOR)法的多属性决策方法。首先拓展补充了直觉模糊距离测度的定义,在此基础上构建了新的直觉模糊距离公式以减少决策信息缺乏,利用直觉模糊熵确定属性与决策者权重,然后再运用新的直觉模糊距离计算VIKOR法中的群体效用和个体后悔度进而得到决策结果,最后,通过实际案例分析验证了该方法的合理性与有效性。

关键词：多属性决策直觉模糊数信息波动性距离测度多准则妥协解排序法

Overland flow resistance and its components for slope surfaces covered with gravel and grass

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International Soil and Water Conservation Research 2022年第2期10卷 273-283页

作者： Lan Ma chengzhong Pan Jingjing Liu Key Laboratory of State Administration of Forestry and Grassland on Soil and Water Conservation School of Soil and Water ConservationBeijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology College of Water SciencesBeijing Normal UniversityBeijing100875China Soil and Water Conservation Monitoring Center of Haihe Basin of Haihe Water Resources Commission of the Ministry of Water Resources Tianjin300170China

Overland flow resistance plays an important role in predicting hillslope hydrological and erosion pro-cesses on *** surfaces covered with grass and/or gravel may increase hydraulic resistance to overland flow,but there is little information on the determination on these resistance components in a composite *** this study,the smooth and sand-bed surfaces covered with different gravel or/and grass(cover degree¼2.5%,5%,10%,15%,20%)under five slope gradients(3,6,9,12,15)were subjected to inflows to investigate the hydraulic resistance and validate the sum law of resistance *** results showed that,the overland flow mainly belonged to transition or turbulent and supercritical flow regime with 150

关键词： Overland flow Resistance Grass Gravel Sum law

Parameter Identification of JONSWAP Spectrum Acquired by Airborne LIDAR

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Journal of Ocean University of China 2017年第6期16卷 998-1002页

作者： YU Yang PEI Hailong XU chengzhong Key Laboratory of Autonomous Systems and Networked Control Ministry of EducationSouth China University of Technology LAGEP Batiment CPEUniversité Claude Bernard Lyon 1

In this study, we developed the first linear Joint North Sea Wave Project(JONSWAP) spectrum(JS), which involves a transformation from the JS solution to the natural logarithmic scale. This transformation is convenient for defining the least squares function in terms of the scale and shape parameters. We identified these two wind-dependent parameters to better understand the wind effect on surface waves. Due to its efficiency and high-resolution, we employed the airborne Light Detection and Ranging(LIDAR) system for our measurements. Due to the lack of actual data, we simulated ocean waves in the MATLAB environment, which can be easily translated into industrial programming language. We utilized the Longuet-Higgin(LH) random-phase method to generate the time series of wave records and used the fast Fourier transform(FFT) technique to compute the power spectra density. After validating these procedures, we identified the JS parameters by minimizing the mean-square error of the target spectrum to that of the estimated spectrum obtained by FFT. We determined that the estimation error is relative to the amount of available wave record data. Finally, we found the inverse computation of wind factors(wind speed and wind fetch length) to be robust and sufficiently precise for wave forecasting.

关键词： JONSWAP spectrum parameter identification least square method airborne LIDAR

Thermodynamic analysis of carbon migration in W1-1.0C steel in plasma surface chromizing

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Journal of University of Science and Technology Beijing 2006年第2期13卷 131-134页

作者： chengzhong Chi Zhiyong He Yuan Gao Zhong Xu College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Research Institute of Surface Engineering Taiyuan University of Technology Taiyuan 030024 China

W 1-1.0C steel was chromized at 1173 K with double glow plasma surface alloying process, and the distribution of Fe, Cr, and C contents in the chromized layer was measured using glow discharge spectrum analysis （GDA）. The behavior and mechanism of carbon migration during the formation of chromized layer were studied through thermodynamic analysis and calculation. The gradient of carbon chemical potential was regarded as the driving force of carbon migration. An equation was derived to describe the carbon content varying with the chromium content within the carbon-rich region. The calculated results from the equation approximated closely to the experimental ones.

关键词： carbon steel chromizing thermodynamic analysis surface alloying carbon migration

MIX-RS:A Multi-Indexing System Based on HDFS for Remote Sensing Data Storage

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Tsinghua Science and Technology 2022年第6期27卷 881-893页

作者： Jiashu Wu Jingpan Xiong Hao Dai Yang Wang chengzhong Xu Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine Intelligence-Synergy Systems Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Faculty of Science and Technology University of MacaoMacao 999078China

A large volume of Remote Sensing(RS)data has been generated with the deployment of satellite *** data facilitate research in ecological monitoring,land management and desertification,*** characteristics of RS data(e.g.,enormous volume,large single-file size,and demanding requirement of fault tolerance)make the Hadoop Distributed File System(HDFS)an ideal choice for RS data storage as it is efficient,scalable,and equipped with a data replication mechanism for failure *** use RS data,one of the most important techniques is geospatial ***,the large data volume makes it time-consuming to efficiently construct and *** that most modern geospatial data centres are equipped with HDFS-based big data processing infrastructures,deploying multiple geospatial indices becomes natural to optimise the ***,because of the reliability introduced by high-quality hardware and the infrequently modified property of the RS data,the use of multi-indexing will not cause large ***,we design a framework called Multi-IndeXing-RS(MIX-RS)that unifies the multi-indexing mechanism on top of the HDFS with data replication enabled for both fault tolerance and geospatial indexing *** the fault tolerance provided by the HDFS,RS data are structurally stored inside for faster geospatial ***,multi-indexing enhances *** proposed technique naturally sits on top of the HDFS to form a holistic framework without incurring severe overhead or sophisticated system implementation *** MIX-RS framework is implemented and evaluated using real remote sensing data provided by the Chinese Academy of Sciences,demonstrating excellent geospatial indexing performance.

关键词： Remote Sensing(RS)data geospatial indexing multi-indexing mechanism Hadoop Distributed File System(HDFS) Multi-IndeXing-RS(MIX-RS)

Encapsulation of selenium sulfide in double-layered hollow carbon spheres as advanced electrode material for lithium storage

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Nano Research 2016年第12期9卷 3725-3734页

作者： Hongwei Zhang Liang Zhou Xiaodan Huang Hao Song chengzhong Yu Australian Institute for Bioengineering and Nanotechnology The University of Queensland Brisbane QLD 4072 Australia State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

Selenium sulfide/double-layered hollow carbon sphere （SeS2/DLHC） composites have been designed as high-performance cathode materials for novel Li-SeS2 batteries. In the constructed composite, SeS2 is predominantly encapsulated in the interlayer space of DLHCs with a high loading of 75% （weight percentage） and serves as the active component for lithium storage. The presence of Se in the composite and the carbon framework not only alleviate the shuttling of polysulfide, but also improve the conductivity of electrodes. Migration of active materials from the interlayer void to the hollow cavity of DLHCs after cycling, which further mitigates the loss of active materials and the shuttle effect, is observed. As a result, the SeS2/DLHC composite delivers a high specific capacity （930 mA.h.g-1 at 0.2 C） and outstanding rate capability （400 mA.h.g-1 at 6 C）, which is much better than those of SeS2/single-layered hollow carbon sphere, Se/DLHC, and S/DLHC composites. Notably, the SeS2/DLHC composite shows an ultralong cycle life with 89% capacity retention over 900 cycles at 1 C, or only 0.012% capacity decay per cycle. Our study reveals that both SeS2 and the double-layered structures are responsible for the excellent electrochemical performance.

关键词： selenium sulfide double-layered hollowcarbon cathode materials lithium storage

Mesoporous resin nanobowls with optimized donor-acceptor conjugation for highly efficient photocatalytic hydrogen peroxide production

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Nano Research 2021年第9期14卷 3267-3273页

作者： Ling Yuan Chaoqi Zhang Jing Wang Chao Liu chengzhong Yu School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200241China Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbaneQueensland 4072Australia

Design of metal-free photocatalysts with customized chemical structure and nano-architecture is promising for photocatalytic hydrogen peroxide(H2O_(2))***,for the first time,mesoporous resorcinol-formaldehyde(MRF)nanobowls with optimized benzenoid-quinoid donor-acceptor(D-A)couples have been synthesized via an assembly-hydrothermal-etching process as high-performance photocatalysts for H2O_(2) production in a sacrificial agent-free *** the hydrothermal temperature of-250℃,MRF-250 exhibits optimized structural features including a large surface area,suitable D-A couple ratio,enhanced light absorption,charge-hole separation and mass ***,MRF-250 shows an unexpected H2O_(2) yield of 19.4 mM·g^(-1)·h^(-1) in pure water,outperforming other RF samples prepared under different conditions and superior to most reported metal-free photocatalysts without the aid of sacrificial *** work paves the way towards the elaborate design of highly effective metal-free photocatalysts for H2O_(2) production.

关键词： donor-acceptor couples mesoporous resin photocatalysts hydrogen peroxide

Effects of Different Light Qualities on the Growth Characteristics of Populus trinervis

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1043-1056页

作者： Jiaqi Li Zhensheng Qiao Dan Zong chengzhong He Key Laboratory for Forest Genetics and Tree Improvement and Propagation in Universities of Yunnan Province Southwest Forestry UniversityKunmingChina Key Laboratory of Biodiversity Conservation in Southwest China State Forestry AdministrationSouthwest Forestry UniversityKunmingChina Key Laboratory for Forestry Resources Conservation and Utilization in the Southwest Mountains of China Ministry of EducationSouthwest Forestry UniversityKunmingChina

Populus trinervis is native to China and plays an irreplaceable role in maintaining the ecological balance of boreal and temperate *** mainly grows in high-altitude *** present,there are limited studies on the response of *** to different light qualities,so it is necessary to investigate the photosynthetic physiological changes of *** in different light *** our study,*** was grown for 8 months under light filtered by three different colored *** three treatments were blue film,green film,and white plastic *** effects of blue(B),green(G),and white(W)light on photosynthetic pigment content,absolute growth,photosynthetic parameters,soluble sugar content,and chlorophyll fluorescence parameters were studied,*** to the Wtreatment,the chlorophyll a and b,carotenoids,total chlorophyll content(a+b),absolute growth of seedling height,net photosynthetic rate(PN),water use efficiency(WUE),total soluble sugars,sucrose,and nonphotochemical quenching(NPQ)of *** were significantly increased under B ***,chlorophyll a and b,carotenoids,total chlorophyll(a+b),transpiration rate(Tr),intercellular CO_(2) concentration(Ci),stomatal conductance(gs),absolute growth of seedling height and leaf length,reducing sugar,total soluble sugar content,and NPQ were significantly increased under G *** results showed that the absolute growth and chlorophyll content of *** were increased under B light,while the sugar and photosynthetic parameters were increased under G *** studies may look into how B light impacts absolute growth and promotional mechanisms,as well as how G light affects the accumulation of sugar levels.

关键词： Blue light green light white light photosynthetic pigment soluble sugar

Bifunctional erdite rods as an effective flocculant and catalyst in electro-Fenton systems

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Progress in Natural Science:Materials International 2023年第4期33卷 518-525页

作者： Tong Sun chengzhong Sun Ying Wang Jiancong Liu Htet Oo Kaung Suiyi Zhu Zhongkai University of Agriculture and Engineering Crude Oil Shipping and Marketing Company Dagang Oilfield Company CNPC Supervision Company Jilin Oilfield Company CNPC School of Environment Northeast Normal University Lversheng Environmental Technology Company

Erdite rods were massively produced via a one-step alkaline heating route with the complete recycling of waste waterwork sludge. The sludge was a mixture of Fe, Mn, Al, and Si, but only Fe-bearing substances were converted as erdite rods. The erdite rods had 100 nm diameter and 1-5 μm length, and was hydrolysed as Fe-SH-rich flocs in wastewater. Its hydrolysis became slow in the presence of electric field but accelerated by adding PMS. pNitrophenol was targeted as organic pollutant to determine the rods performance. The removal efficiency of pnitrophenol was 7.4% by adding erdite rods, but up to 44.6% with the addition of erdite/PMS, and then dramatically increased to 98.7% in the electro-PMS/erdite system. Given that the free Fe was less than 30 mg/L,the surface Fe of Fe-SH-rich flocs predominated the PMS activation, in which the surface Fe enriched in electronic field and then was involved in the redox reaction of PMS and then reduced by the adjacent S on flocs. This enabled the recycling of Fe3+/Fe2+to activate PMS at high level. Thus, the erdite rods showed high p-nitrophenol removal efficiency in the electro-Fenton system in comparison with the other reported reagents, e.g. ferrous sulphate,ferbam, pyrite and FeS.

关键词： Erdite rods p-Nitrophenol Fenton reaction Wastewater treatment Flocculant