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Layout Optimization for Greenhouse WSN Based on Path Loss Analysis

Computer Systems Science & Engineering 2021年第4期37卷 89-104页

作者： Huarui Wu Huaji Zhu Xiao Han Wei Xu National Engineering Research Center for Information Technology in agriculture Beijing100097 China 2 Beijing Research Center for Information Technology in agriculture Beijing Academy of Agriculture and Forestry SciencesBeijing100097 China 3 Key Laboratory of Agri-Informatics Ministry of AgricultureBeijing100097 China 4 Department of Biosystems MechatronicsBiostatistics and SensorsKU LeuvenHeverlee3001Belgium

When wireless sensor networks (WSN) are deployed in the vegetablegreenhouse with dynamic connectivity and interference environment, it is necessary to increase the node transmit power to ensure the communication quality,which leads to serious network interference. To offset the negative impact, thetransmit power of other nodes must also be increased. The result is that the network becomes worse and worse, and node energy is wasted a lot. Taking intoaccount the irregular connection range in the cucumber greenhouse WSN, wemeasured the transmission characteristics of wireless signals under the 2.4 Ghzoperating frequency. For improving network layout in the greenhouse, a semiempirical prediction model of signal loss is then studied based on the measureddata. Compared with other models, the average relative error of this semi-empiricalsignal loss model is only 2.3%. Finally, by combining the improved networktopology algorithm and tabu search, this paper studies a greenhouse WSN layoutthat can reduce path loss, save energy, and ensure communication quality. Giventhe limitation of node-degree constraint in traditional network layout algorithms,the improved algorithm applies the forwarding constraint to balance network energyconsumption and constructs asymmetric network communication links. Experimentalresults show that this research can realize the energy consumption optimization ofWSN layout in the greenhouse.

关键词： Pathloss model vegetable greenhouse networktopology networklayout

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Time-Series Modeling and Prediction of Global Monthly Absolute Temperature for Environmental Decision Making

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Advances in Atmospheric Sciences 2013年第2期30卷 382-396页

作者： YE Liming YANG Guixia Eric VAN RANST TANG Huajun Key Laboratory of Agri-Informatics Ministry of Agriculture/Institute ofAgricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences Beijing 100081 Department of Geology and Soil Science (WE13) Ghent University Krijgslaan 281 9000 Gent Belgium Chinese Academy of agricultural Sciences Beijing 100081

A generalized, structural, time series modeling framework was developed to analyze the monthly records of absolute surface temperature, one of the most important environmental parameters, using a deterministicstochastic combined （DSC） approach. Although the development of the framework was based on the characterization of the variation patterns of a global dataset, the methodology could be applied to any monthly absolute temperature record. Deterministic processes were used to characterize the variation patterns of the global trend and the cyclic oscillations of the temperature signal, involving polynomial functions and the Fourier method, respectively, while stochastic processes were employed to account for any remaining patterns in the temperature signal, involving seasonal autoregressive integrated moving average （SARIMA） models. A prediction of the monthly global surface temperature during the second decade of the 21st century using the DSC model shows that the global temperature will likely continue to rise at twice the average rate of the past 150 years. The evaluation of prediction accuracy shows that DSC models perform systematically well against selected models of other authors, suggesting that DSC models, when coupled with other ecoenvironmental models, can be used as a supplemental tool for short-term （10-year） environmental planning and decision making.

关键词： time series analysis statistical model polynomial trend Fourier method ARIMA climatechange

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Development and test verification of air temperature model for Chinese solar and Spainish Almeria-type greenhouses

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International Journal of agricultural and Biological Engineering 2017年第4期10卷 66-76页

作者： Jorge Antonio Sanchez-Molina Li Ming Francisco Rodriguez Jose Luis Guzman Wang Hui Yang Xinting The Automatic Control Robotics and Mechatronics Research GroupDepartment of InformaticsceiA3CIESOLUniversity of AlmeriaAlmeria 04120Spain Beijing Research Center for Information Technology in agriculture/National Engineering Research Center for Information Technology in agriculture/National Engineering laboratory for agri-product Quality Traceability/key laboratory for Information Technologies in agriculture Ministry of AgricultureBeijing 100097China

Growth can be defined as an increment in biomass or an increment in weight or height of the organs of the plant influenced by physiological processes.Many of these processes have their limits genetically determined,but climate and irrigation play an important role.Because of its importance,microclimate has been extensively studied in the modeling as a surrounding condition which is imposed by the exterior climate.The main objective of this work was to develop a temperature model based on the energy balance dynamics at two different greenhouse locations-South-eastern Spain and Northern China,and the traditional structures of Chinese solar greenhouse and Almería-type multi-span greenhouse were taken into account.The final model was developed by combining the external conditions,the actuator influence and the crop growth,where the temperature is influenced by soil,crop,cover,actuators,back wall and greenhouse geometry.The model took into account the energy lost by convective and conductive fluxes,as well as the energy supplied by solar radiation and heating systems.The soil and the back wall are the main media for energy storage.The temperature dynamic was determined by a physical model,which considered the energy balance from a holistic point of view-as a sub-model for a customizable interface among the external climate,the plant and the greenhouse system.The influences of different subsystems included in the temperature model were analyzed and evaluated.The results showed a high R^(2)value of 0.94 for Beijing and 0.95 for Almeria,and the average error was low,of which the MAE and RMSE were 0.71 and 1.365 for Almeria and 0.62 and 1.102 for Beijing,respectively.Thus,the model can be considered as a powerful tool for control design purposes in microclimate systems.

关键词： air temperature model Chinese solar greenhouse Spanish Almería-type greenhouse energy balance dynamics microclimate

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Structural identification and antioxidant potency evaluation of pomelo vinegar polyphenols

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Food Bioscience 2022年第3期47卷 645-653页

作者： Bo Zou Ting Li Yujuan Xu Yuanshan Yu Jijun Wu Sericultural & agri-Food Research Institute Guangdong Academy of agricultural Sciences/key laboratory of Functional Foods Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products ProcessingGuangzhou510610China

Polyphenols are the main antioxidant ingredient of honey pomelo vinegar.However,the antioxidant contributions of various individual phenolics to total polyphenols and antioxidant mechanism are unclear.In this study,phenolic compounds were identified,and the antioxidant potency and antioxidant contribution of individual phenolics were analyzed.The antioxidant mechanism was also studied in HepG2 cells.A total of seven phenolics were identified,including naringin,narirutin,rhoifolin,vanillic acid,methyl hesperidin,vicenin-2,and ferulic acid;among which,ferulic acid had the highest extracellular antioxidant potency,while methyl hesperidin had the lowest.Without considering the synergistic effect of the phenolics,naringin,ferulic acid,and vicenin-2 were major contributors to the antioxidant potency of pomelo vinegar polyphenols(PVP)using four antioxidant assays.PVP at the concentrations of 20μg/mL and 100μg/mL had a protective effect against H_(2)O_(2)-induced oxidative damage to HepG2 cells.PVP also reduced lactic dehydrogenase(LDH)release and reactive oxygen species(ROS)accumulation in cells.The western blotting results revealed that PVP promoted translocation of NFE2-related factor 2(Nrf2)from the cytoplasm to the nucleus and up-regulated the expression of its governed antioxidant enzymes such as NAD(P)H:quinone oxidoreductase 1(NQO1),heme oxygenase-1(HO-1),glutathione S-transferase A2(GSTA2),and glutamate-cysteine ligase catalytic subunit(GCLC).In summary,PVP could serve as a potential therapeutic agent for oxidative stress-related disorders.

关键词： Antioxidant Polyphenols Pomelo vinegar HepG2 Nrf2

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Climate Change Impact and Its Contribution Share to Paddy Rice Production in Jiangxi, China

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Journal of Integrative agriculture 2014年第7期13卷 1565-1574页

作者： LI Wen-juan TANG Hua-jun QIN Zhi-hao YOU Fei WANG Xiu-fen CHEN Chang-li JI Jian-hua LIU Xiu-mei Institute of agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Key Laboratory of Agri-Informatics Ministry of Agriculture/Chinese Academy of Agricultural Sciences International Institute for Earth System Science Nanjing University Institute of Crop Sciences Chinese Academy of Agricultural Sciences Institute of Soil Fertilizer and Resource Environment Jiangxi Academy of Agricultural Sciences

In the study, an improved approach was proposed to identify the contribution shares of three group factors that are climate, technology and input, social economic factors by which the grain production is shaped. In order to calibrate the method, Jiangxi Province, one of the main paddy rice producers in China was taken as an example. Based on 50 years （1961-2010） meteorological and statistic data, using GIS and statistical analysis tools, the three group factors that in certain extent impact China＇s paddy rice production have been analyzed quantitatively. The individual and interactive contribution shares of each factor group have been identiifed via eta square （η2）. In the paper, two group ordinary leasr square （OLS） models, paddy models and climate models, have been constructed for further analysis. Each model group consists of seven models, one full model and six partial models. The results of paddy models show that climate factors individually and interactively contribute 11.42-15.25%explanatory power to the variation of paddy rice production in the studied province. Technology and input factors contribute 16.17%individually and another 8.46%interactively together with climate factors, totally contributing about 25%. Social economic factors contribute about 7%of which 4.65%is individual contribution and 2.49%is interactive contribution together with climate factors. The three factor groups individually contribute about 23%and interactively contribute additional 41%to paddy rice production. In addition every two of the three factor groups also function interactively and contribute about 22%. Among the three factor groups, technology and input are the most important factors to paddy rice production. The results of climate models support the results of paddy models, and display that solar radiation （indicated by sunshine hour variable） is the dominate climate factor for paddy rice production.

关键词： climate change food security paddy rice production contribution share China

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Effects of sgRNA length and number on gene editing efficiency and predicted mutations generated in rice

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The Crop Journal 2022年第2期10卷 577-581页

作者： Xiaojing Liu Jiangtao Yang Yaya Song Xiaochun Zhang Xujing Wang Zhixing Wang Biotechnology Research Institute Chinese Academy of Agricultural Sciences/MARA Key Laboratory on Safety Assessment(Molecular)of Agri-GMOBeijing 100081China

CRISPR-Cas9 is a common tool for gene editing, and appropriate sg RNAs are the key factor for successful editing. In this study, the effect of sg RNA length and number on editing efficiency was analyzed in rice using CYP81 A6 as the target gene. A series of CRISPR-Cas9 plant expression vectors containing single sg RNAs with different lengths(17, 18, 19, 20, 21, 22, 23 nt) or two sg RNAs were constructed and introduced into rice cultivar Zhonghua11 by Agrobacterium-mediated transformation. Analysis of the editing status of 1283 transgenic rice plants showed that 371 were successfully edited with base preference.Single A or T insertions were the most frequent among the six edited types. The editing efficiency of transgenic rice with two sg RNAs was higher than that with a single sg RNA. Editing efficiency and sg RNA length showed a normal distribution with 20 nt sg RNA(25%) being the most efficient. The editing efficiency decreased slightly with decreases of 1–2 bases(19 nt 20%, 18 nt 21%), but decreased significantly with a decrease of 3 bases(17 nt 4.5%). Editing efficiency was significantly reduced by adding 1 to 3 bases(21 nt 16.8%, 22 nt 13%, 23 nt 13%) to the sg RNA. These results provide data for successful gene editing or rice by CRISPR-Cas9.

关键词： CRISPR-Cas9 sgRNA number sgRNA length Editing efficiency

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agricultural cooperatives and the role of organisational models in new intelligent traceability systems and big data analysis

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International Journal of agricultural and Biological Engineering 2017年第5期10卷 115-125页

作者： Cynthia Giagnocavo Fernando Bienvenido Li Ming Zhao Yurong Jorge Antonio Sanchez-Molina Yang Xinting Cátedra(Chair)Coexphal-UAL of Horticulture Cooperative Studies and Sustainable DevelopmentUniversity of AlmeriaSpain Department of informatics University of AlmeriaAlmeriaSpain Beijing Research Center for Information Technology in agriculture/National Engineering Research Center for Information Technology in agriculture/National Engineering laboratory for agri-product Quality Traceability/key laboratory for Information Technologies in agriculture Ministry of AgricultureChina College of Economics and Management Shandong Agricultural UniversityChina

Traceability systems are key to assuring food safety,creating a benefit for food supply chain components.Currently,the appearance of new technologies such as IoT and Big Data Analysis leads to a new generation of more functional,but complex,traceability systems.Organisational models based on cooperation of multiple small/medium size agents,for example of small/family farming cooperatives,play an important role in high standard agricultural production and commercialization processes.These function as both social and economic networks,with high social and economic impact in the rural areas.The case of Almeria as an example of this model was used to analyze its cooperative model.The actual traceability systems in the Almeria model were studied,taking account of the different networked agents and their interrelation.This study includes two main parts:a)analysis of the net-chains that constitute the food supply chains and their different relationships,and b)actual traceability.The next step studied how the net-chain model,including many diverse agents,may be applied to develop a new generation of traceability systems based of IoT and Big Data.This implies extending the special and functional scope of the actual systems and defining clear rules of exchange of the results of the Big Data Analysis,taking account of the adequate Privacy Rules.This work analyses the current organisation as a base for a new generation of traceability systems considered in the European project IoF2020(Internet of the Food and Farm 2020).Some parallels between Almeria’s model and certain areas in China,mainly in the areas of Beijing-Tianjin-Hebei and Shandong were detected.Another of the objectives of this work is to deepen the understanding of these similarities and analyze the possible adaptation of the results from Almeria to China.

关键词： food traceability system big data internet of things organisational structure business model agricultural cooperatives net-chains food supply chain

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青藏高原植被结构变化反映环境变迁

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Science Bulletin 2023年第17期68卷 1928-1937页

作者：王艳芬薛凯胡容海丁柏阳曾弘李瑞津徐斌庞哲宋小宁李聪佳杜剑卿杨秀春张泽林郝彦宾崔骁勇郭柯高清竹张扬建朱军涛孙建李耀明姜丽丽周华坤罗彩云张振华高庆波陈世龙纪宝明徐兴良陈槐李奇赵亮徐世晓刘雅莉胡林勇武建双杨其恩董世魁贺金生赵新全汪诗平朴世龙于贵瑞傅伯杰 College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of SciencesBeijing 101408China State key laboratory of Tibetan Plateau Earth System Environment and ResourcesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China State key laboratory of Plateau Ecology and agriculture Qinghai UniversityXining 810016China key laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810001China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou 256606China College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Key Laboratory of Agri-Informatics Ministry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China School of Grassland Science Beijing Forestry UniversityBeijing 100083China State key laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Institute of Environment and Sustainable Development in agriculture Chinese Academy of Agricultural SciencesBeijing 100081China key laboratory for Agro-Environment&Climate Change Ministry of AgricultureBeijing 100081China key laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China key laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration Biodiversity Conservation key laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Zoige Peatland and Global Change Research Station Chinese Academy of SciencesHongyuan 62

草地植被结构对于其生产和生态功能至关重要,但大尺度信息严重匮乏.本研究结合多源遥感数据和深度学习,在区域尺度上厘清了青藏高原高寒草地基于群系的植物群落结构空间格局,并比较了其历史变化.过去40年,高寒草甸在高寒草地中的比例从... 详细信息

草地植被结构对于其生产和生态功能至关重要,但大尺度信息严重匮乏.本研究结合多源遥感数据和深度学习,在区域尺度上厘清了青藏高原高寒草地基于群系的植物群落结构空间格局,并比较了其历史变化.过去40年,高寒草甸在高寒草地中的比例从50%上升到69%,反映了变暖变湿的环境变化.此外,高寒草甸和高寒草原中高山嵩草草甸和紫花针茅草原的优势度分别增强到76%和92%.其中,气候因子驱动了紫花针茅草原近些年的分布;高山嵩草草甸近些年的分布则并非完全由气候驱动,人类活动可能起重要作用.本研究首次探索了区域尺度植被结构特征与历史变化,为认识青藏高原草地变化的驱动力及其空间异质性提供了新视角.

关键词：高寒草地植被结构草地植被多源遥感数据深度学习植物群落结构区域尺度高寒草原

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An analysis of the mechanism underlying photocatalytic disinfection based on integrated metabolic networks and transcriptional data

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Journal of Environmental Sciences 2020年第6期32卷 28-37页

作者： Xiao-Long Liang Zhan-Min Liang Shuo Wang Xiao-Hui Chen Yao Ruan Qing-Ye Zhang Hong-Yu Zhang Hubei key laboratory of agricultural Bioinformatics College of InformaticsHuazhong Agricultural UniversityWuhan430070PR China

Photocatalytic disinfection has long been used to combat pathogenic bacteria.However,the specific mechanism underlying photocatalytic disinfection and its corresponding targets remain unclear.In this study,an analysis of the potential mechanism underlying photocatalytic disinfection was performed based on integrated metabolic networks and transcriptional data.Two sets of RNA-seq data(wild type and a photocatalysis-resistant mutant mediated by titanium dioxide(TiO2))were processed to constrain the genome scale metabolic models(GSMM)of E.coli.By analyzing the metabolic network,the differential metabolic flux of every reaction was computed in constrained GSMM,and several significantly differential metabolic fluxes in reactions were extracted and analyzed.Most of these reactions were involved in the transmembrane transport of substances and occurred on the inner membrane or were an important component of the cell membrane.These results,which are consistent with the reported information,validated our analysis process.In addition,our work also identified other new and valuable metabolic pathways,such as the reaction ALCD2x,which has a great effect on the energy production process under bacterial anaerobic conditions.The DHAK reaction is also related to the metabolic process of ATP.These reactions with large differential metabolic fluxes merit further research.Additionally,to provide a strategy to address photocatalysis-resistant mutant bacteria,a metabolic compensation analysis was also performed.The metabolic compensation analysis results provided suggestions for a combined method that can effectively combat resistant bacteria.This method could also be used to explore the mechanisms of drug resistance in other microorganisms.

关键词： Photocatalytic disinfection Genome scale metabolic models(GSMM) RNA-seq analysis Mechanism Metabolic compensation

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Recent advances in emerging techniques for non-destructive detection of seed viability: A review

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Artificial Intelligence in agriculture 2019年第1期1卷 35-47页

作者： Yu Xia Yunfei Xu Jiangbo Li Chi Zhang Shuxiang Fan Beijing Research Center of Intelligent Equipment for agriculture Beijing 100097China National Research Center of Intelligent Equipment for agriculture Beijing 100097China Key Laboratory of Agri-Informatics Ministry of AgricultureBeijing 100097China Beijing key laboratory of Intelligent Equipment Technology for agriculture Beijing 100097China College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China

Over the past decades,imaging and spectroscopy techniques have been developed rapidly with widespread applications in non-destructive agro-food quality determination.Seeds are one of themost fundamental elements of agriculture and forestry.Seed viability is of great significance in seed quality characteristics reflecting potential seed germination,and there is a great need for a quick and effective method to determine the germination condition and viability of seeds prior to cultivate,sale and plant.Some researches based on spectra and/or image processing and analysis have been explored in terms of the external and internal quality of a variety of seeds.Many attempts have been made in image segmentation and spectra correction methods to predict seed quality using various traditional and novel methods.This review focuses on the comparative introduction,development and applications of emerging techniques in the analysis of seed viability,in particular,near infrared spectroscopy,hyperspectral and multispectral imaging,Raman spectroscopy,infrared thermography,and soft X-ray imaging methods.The basic theories,principle components,relative chemometric processing,analytical methods and prediction accuracies are reported and compared.Additionally,on the foundation of the observed applications,the technical challenges and future outlook for these emerging techniques are also discussed.

关键词： Seed viability NIR Hyperspectral imaging Raman spectroscopy Infrared thermography Soft X-ray imaging

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