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Structural design and thermal performance simulation of shade roof of double-slope greenhouse for mushroom-vegetable cultivation

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International Journal of Agricultural and Biological Engineering 2019年第3期12卷 126-133页

作者： Yunfei Ma Xinxing Li zetian fu Lingxian Zhang College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Institute of Yantai China Agricultural UniversityYantai 264670China Key Laboratory of Agricultural Informationization Standardization Ministry of Agriculture and Rural AffairsBeijing 100083China

A new type of roof structure was developed for the shade room in a double-slope greenhouse used for mushroom-vegetable planting.A simulation model was developed to evaluate the thermal performance of the new roof with an insulation thickness of 0.12 m in Beijing,*** results showed that(1)the indoor air temperature of the shade room with the newly implemented shade roof was 2.7℃-4.9℃ higher than that of an ordinary shade room during the winter months;(2)The indoor air temperature of the solar room adjacent to the shade room with the new roof was higher than that of the ordinary solar room and the minimum indoor air temperature of the solar room was increased 1.9℃ at winter night;(3)the indoor temperature of the shade room with the new roof design was 2℃-4℃ lower than that of the ordinary shade room during the summer months;(4)Under factory production conditions,which were conducted in a controlled environment to promote the annual growth of the edible fungus,the heating energy consumption of the shade room after the implementation of the new roof structure was reduced by 69.3%,the amounted to total energy savings of 61.3% per *** new roof structure provided a significant improvement in the thermal environment compared to an ordinary shade room,improved the vegetable growth in the winter,and also significantly reduced the energy consumption and production costs.

关键词： double-slope greenhouse roof structure design thermal performance simulation mushroom-vegetable planting

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Growth monitoring of greenhouse lettuce based on a convolutional neural network

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Horticulture Research 2020年第1期7卷 1161-1172页

作者： Lingxian Zhang Zanyu Xu Dan Xu Juncheng Ma Yingyi Chen zetian fu China Agricultural University Beijing 100083China Key Laboratory of Agricultural Informationization Standardization Ministry of Agriculture and Rural AffairsBeijingChina Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China

Growth-related traits,such as aboveground biomass and leaf area,are critical indicators to characterize the growth of greenhouse ***,nondestructive methods for estimating growth-related traits are subject to limitations in that the methods are susceptible to noise and heavily rely on manually designed *** this study,a method for monitoring the growth of greenhouse lettuce was proposed by using digital images and a convolutional neural network(CNN).Taking lettuce images as the input,a CNN model was trained to learn the relationship between images and the corresponding growth-related traits,i.e.,leaf fresh weight(LFW),leaf dry weight(LDW),and leaf area(LA).To compare the results of the CNN model,widely adopted methods were also *** results showed that the values estimated by CNN had good agreement with the actual measurements,with R^(2) values of 0.8938,0.8910,and 0.9156 and normalized root mean square error(NRMSE)values of 26.00,22.07,and 19.94%,outperforming the compared methods for all three growth-related *** obtained results showed that the CNN demonstrated superior estimation performance for the flat-type cultivars of Flandria and Tiberius compared with the curled-type cultivar of *** tests were conducted by using images of Tiberius from another growing *** results showed that the CNN was still capable of achieving accurate estimation of the growth-related traits,with R2 values of 0.9277,0.9126,and 0.9251 and NRMSE values of 22.96,37.29,and 27.60%.The results indicated that a CNN with digital images is a robust tool for the monitoring of the growth of greenhouse lettuce.

关键词： neural network estimation

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Decomposition of influencing factors and its spatial-temporal characteristics of vegetable production:A case study of China

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Information Processing in Agriculture 2018年第4期5卷 477-489页

作者： Jieqiong Wang zetian fu Biao Zhang Fei Yang Lingxian Zhang Bo Shi China Agricultural University Beijing 100083China Beijing Laboratory of Food Quality and Safety Beijing 100083China College of Economics Fuyang Normal UniversityFuyang 236037China Key Laboratory of Agricultural Informationization Standardization Ministry of AgricultureBeijing 100083China

China is the largest producer and consumer of vegetables,its vegetable industry is playing an important role in the domestic agricultural sector and global vegetable export *** is important to promote the long-term sustainable development of Chinese vegetable industry for food security and quality of people’s *** find out the intrinsic way to promote the development of Chinese vegetable industry,this paper analyzed the influencing factors of Chinese vegetable production by utilizing the LMDI method and demonstrated the spatial-temporal characteristics of vegetable production through application of the Arc-GIS spatial autocorrelation analysis *** results showed that the influencing factors of vegetable production were the cultivated land area,multiple cropping index,vegetable planting proportion and vegetable yield per hectare in *** major driving factor had changed from vegetable planting proportion to vegetable yield per *** influencing degrees of factors on vegetable production are different in different regions,regionalization is therefore a major feature of Chinese vegetable *** government should take production technology,regionalization-driven effect,and marketing integration into consideration to promote the development of Chinese vegetable industry.

关键词： Vegetable production Influencing factors Contribution ratio Logarithmic mean Divisia index(LMDI)

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Sn-doped cobalt containing perovskite as the air electrode for highly active and durable reversible protonic ceramic electrochemical cells

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Journal of Advanced Ceramics 2024年第1期13卷 63-72页

作者： Min fu Wenjing Hu Hua Tong Xin Ling Linggui Tan Fanglin Chen zetian Tao School of Resources Environment and Safety EngineeringUniversity of South ChinaHengyang 421001China Department of Mechanical Engineering University of South CarolinaColumbia 29208USA

One potential solution to the problems of energy storage and conversion is the use of reversible protonic ceramic electrochemical cells(R-PCEC),which are based on the solid oxide fuel cell(SOFC)technology and offer a flexible route to the generation of renewable ***,the R-PCEC development faces a range of significant challenges,including slow oxygen reaction kinetics,inadequate durability,and poor round-trip efficiency resulting from the inadequacy of an air *** address these issues,we report novel B-sites doped Pr_(0.5)Ba_(0.5)Co_(0.7)Fe_(0.3)O_(3−δ)(PBCF)with varying amounts of Sn as the air electrode for R-PCEC to further enhance electrochemical performance at lower *** 600℃,R-PCEC with an air electrode consisting of Pr_(0.5)Ba_(0.5)Co_(0.7)Fe_(0.25)Sn_(0.05)O_(3+δ)has achieved peak power density of 1.12 W∙cm^(−2) in the fuel cell mode and current density of 1.79 A∙cm^(−2) in the electrolysis mode at a voltage of 1.3 ***,R-PCECs have shown good stability in the electrolysis mode of 100 *** study presents a practical method for developing durable high-performance air electrodes for R-PCECs.

关键词： triple conducting oxide dual-element doping protonic ceramic electrochemical cells(PCECs) catalytic

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Multi-wavelength nanowire micro-LEDs for future high speed optical communication

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Opto-Electronic Advances 2024年第3期7卷 1-3页

作者： Ayush Pandey zetian Mi Department of Electrical Engineering and Computer Science University of MichiganAnn ArborMI 48109USA

The future of optoelectronics is directed towards small-area light sources,foremost being ***,their use has been inhibited so far primarily due to fabrication and integration challenges,which impair efficiency and ***,bottom-up nanostructures grown using selective area epitaxy have garnered attention as a solution to the aforementioned *** fu *** used this technique to demonstrate uniform p-i-n core-shell InGaAs/InP nanowire array light emitting *** devices are capable of voltage and geometry-controlled multi-wavelength and high-speed *** publication accentuates the wide capabilities of bottom-up nanostructures to resolve the difficulties of nanoscale optoelectronics.

关键词： communication high operations

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我国农业工程技术发展战略及措施

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农业机械学报 2007年第5期38卷 74-76页

作者：白京宇傅泽田中国农业大学工学院

农业工程技术是实现农业现代化的重要技术手段,加快农业工程技术创新及新技术的研究、开发、推广是我国农业发展的必然要求。分析了我国农业工程技术发展现状,提出了我国农业工程技术的发展战略和政策措施。

关键词：农业工程发展战略综述

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Factors of e-Knowledge Project Success for Rural Development

Factors of e-Knowledge Project Success for Rural Development

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作者： Weizhe Feng Yanqing Duan Yan Qi zetian fu International College at Beijing China Agricultural University Business School University of Bedfordshire College of Information and Electrical Engineering China Agricultural University

An ICT based knowledge transfer projects,locally called e-knowledge projects in China,are seen as an importance measure to improve farmer’s farming efficiency and life *** dynamic rural economic and social circumstances require an e-knowledge project to be effectively *** this study,an e-knowledge project success model was proposed and empirically *** hypothesized model was developed based on the modification of a widely recognized information system success model proposed by DeLone and *** equation modeling technique was employed to verify the hypothesized *** a result,six factors were identified for assessing the success of e-knowledge project for rural *** factors included knowledge quality,extension quality,system quality,use,user’s satisfaction and individual *** each success factors,there were a series of measures that could be applied to assess a project *** discussion,the application of the e-knowledge project success model and further research were highlighted.

关键词： Factors e-Knowledge Rural Development Structure Equation Modeling

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A Survey of Stickiness of Agriculture Knowledge Acquisition in China

A Survey of Stickiness of Agriculture Knowledge Acquisition ...

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作者： Weizhe Feng Daoliang Li Yanqing Duan zetian fu International College at Beijing China Agricultural University College of Information and Electrical Engineering China Agricultural University Business School University of Bedfordshire

The concept of stickiness in this study was borrowed from information research literature,which indicated the complex and difficulties in all process of knowledge transfer that including knowledge *** reveal the stickiness of agriculture knowledge acquisition in China,a survey was conducted of agriculture related websites in ***,an intensive literature review was done for collecting attributes closely associated with agriculture knowledge and its acquisition ***,these attributes were categorized and transformed into questionnaire and surveyed in14 provinces in ***,the data were tested with principal component analysis *** results,this study concluded that four factors that may affect the stickiness of agriculture knowledge,namely,difficulty,special tacitness,available explicitness,and proven knowledge;five factors that may affect stickiness of agriculture *** include attitudes,professional,expression capability,teamwork,and protectiveness;and five factors that may affect stickiness of agriculture institutions,attitudes,service orientation,distance,protectiveness,and *** conclusion,it was suggested that the three groups of principal factors can be used to guide the planning and assessment of ICT-based knowledge projects in rural *** study also highlighted a new area for ICT-based information and knowledge transfer research.

关键词： Stickiness Agriculture Knowledge Acquisition Principal Component Analysis

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Development of Time-Temperature Data Collection Program for Frozen Fish in the Cold Chain

Development of Time-Temperature Data Collection Program for ...

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作者： Lu Liu Jinyou Hu Jingjing Zhang zetian fu Jian Zhang China Agricultural University Beijing Information S&T University

A systematic approach for fish quality modeling and time-temperature data collection program in order to analyze the temperature dependence at different stages for the fish cold chain was *** paper describes an implementation of several kinds of time-temperature loggers to get comprehensive environmental temperature data over the cold *** with temperature sensors,time-temperature detectors,iButtons and TTIs are respectively used to get temperature data of air,liquid and fish inside by stages of processing and *** response of timetemperature recorders from every steps experiment was also *** functions were used to model the quality spoilage by the time-temperature data *** using single temperature data instruments,different kinds of temperature data instruments is able to collect temperature data in different environment for the result of the experiment to be more sufficiently and informative.

关键词： Cold Chain Frozen Fish Quality Change Time-Temperature Profiles

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水产品冷链管理决策模型的构建

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农业工程学报 2010年第8期26卷 379-385页

作者：刘璐岳峻张健傅泽田中国农业大学工学院北京100083 鲁东大学信息科学与工程学院烟台264000 北京信息科技大学经济管理学院北京100085

为了解决目前水产品冷链信息管理中缺乏对冷链环境信息与水产品品质信息的关联性综合分析的问题,该文以水产品冷链信息为研究对象,将加工、仓储与运输信息分解成为事件与状态集合,并引入时间、温度信息设计数据结构对事件与状态信息进... 详细信息

为了解决目前水产品冷链信息管理中缺乏对冷链环境信息与水产品品质信息的关联性综合分析的问题,该文以水产品冷链信息为研究对象,将加工、仓储与运输信息分解成为事件与状态集合,并引入时间、温度信息设计数据结构对事件与状态信息进行定义与描述。采用状态与事件分离的描述形式,对决策信息进行操作规范与品质评价的判定。针对冷链信息进行了时间、温度标志,分别建立阈值判断作为操作安全的决策模型和品质评价模型。最后,以罗非鱼冷链物流过程为例,构建冷链信息决策方案,将罗非鱼的品质划分为5个区间进行分析。选择罗非鱼品质的第四区间(0.2～0.4)作为其品质安全的参考值,罗非鱼的保质期为18d,与实际保质期17.13d相比误差较小。结果表明,将冷链环境数据与水产品品质信息相结合,对水产品品质在冷链流通的全过程进行分析与评价,可以对水产品冷链信息进行有效的管理,为水产品冷链的安全做出决策提供了依据。

关键词：质量控制决策支持信息分析食品安全冷链品质评价

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