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Film-mulched continuous ridge-furrow planting improves soil temperature,nutrient content and enzymatic activity in a winter oilseed rape field,Northwest China

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Journal of Arid Land 2018年第3期10卷 362-374页

作者： gu xiaobo LI Yuannong DU Yadan Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F University

Film mulching system is a widely employed agricultural practice worldwide. However, the effects of different planting and mulching patterns on soil nutrient content and enzymatic activity have not been well documented. In this study, we examined the impact of four planting and mulching patterns（including control, flat planting without mulching; M1, flat planting with film mulching; M2, ridge-furrow planting with film mulching on both ridges and furrows; and M3, ridge-furrow planting with film mulching on continuous ridges） on the seed yield of winter oilseed rape, soil moisture, soil temperature, soil organic carbon（SOC） content, soil nutrient content, and soil enzymatic activity over three growing seasons from 2012 to 2015 in a winter oilseed rape field in the semi-arid area of Northwest China. Seed yield of winter oilseed rape, soil moisture, soil temperature, enzymatic activities, and contents of nitrate-nitrogen, available phosphorus, and available potassium were all significantly higher in mulching treatments（M1, M2 and M3） than in control treatment over the three growing seasons, whereas SOC content was significantly lower in mulching treatments than in control treatment during 2013–2014 and 2014–2015. Among the three mulching treatments（M1, M2 and M3）, the M3 treatment showed consistently higher seed yield, SOC content, nutrient contents, and enzymatic activities than the other two treatments. Seed yield of winter oilseed rape was 41.1% and 15.0% higher in M3 than in M1 and M2, respectively. SOC content and soil enzymatic activities in the top 0–20 cm soil layers and nitrate-nitrogen content in the top 0–30 cm soil layers were all significantly higher in M3 than in M1 and M2. Therefore, we advise the ridge-furrow planting with film mulching on continuous ridges（i.e., M3） as an efficient planting and mulching pattern for sustainably improving the seed yield of winter oilseed rape and preserving soil fertility in the semi-arid area of Northwest China.

关键词： film mulching soil temperature soil organic carbon soil nutrient content soil enzymatic activity winteroilseed rape Northwest China

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Time synchronization and ranging under unknown positions and velocities

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Science China(Technological Sciences) 2017年第2期60卷 271-281页

作者： gu xiaobo CHANG Qing XU Yong WANG Dun School of Electronic & Information Engineering Beihang University Space Star Technology Co. Ltd

The process to achieve time synchronization and ranging for a network of mobile nodes is raising a concern among researchers, and hence a variety of joint time synchronization and ranging algorithms have been proposed in recent years. However, few of them handle the case of all-node motion under unknown positions and velocities. This study addresses the problem of determining ranging and time synchronization for a group of nodes moving within a local area. First, we examined several models of clock discrepancy and synchronous two-way ranging. Based upon these models, we present a solution for time synchronization with known positions and velocities. Next, we propose a functional model that jointly estimates the clock skew, clock offset, and time of flight in the absence of a priori knowledge for a pair of mobile nodes. Then, we extend this model to a network-wide time synchronization scheme by way of a global least square estimator. We also discuss the advantages and disadvantages of our model compared to the existing algorithms, and we provide some applicable scenarios as well. Finally, we show that the simulation results verify the validity of our analysis.

关键词： time synchronization two-way ranging relative motion clock model joint estimation

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Approximately orthogonal nonnegative Tucker decomposition for flexible multiway clustering

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Science China(Technological Sciences) 2021年第9期64卷 1872-1880页

作者： QIU YiChun SUN WeiJun ZHANG Yu gu xiaobo ZHOU guoXu School of Automation Guangdong University of TechnologyGuangzhou 510006China Key Laboratory of Intelligent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Department of Bioengineering Lehigh UniversityBethlehemPA 18015USA guangdong-Hong Kong-Macao Joint Laboratory for Smart Manufacturing Guangzhou 510006China guangdong Key Laboratory of IoT Information Technology Guangzhou 510006China

High-order tensor data are prevalent in real-world applications, and multiway clustering is one of the most important techniques for exploratory data mining and compression of multiway data. However, existing multiway clustering is based on the K-means procedure and is incapable of addressing the issue of crossed membership degrees. To overcome this limitation, we propose a flexible multiway clustering model called approximately orthogonal nonnegative Tucker decomposition(AONTD). The new model provides extra flexibility to handle crossed memberships while fully exploiting the multilinear property of tensor *** accelerated proximal gradient method and the low-rank compression tricks are adopted to optimize the cost function. The experimental results on both synthetic data and real-world cases illustrate that the proposed AONTD model outperforms the benchmark clustering methods by significantly improving the interpretability and robustness.

关键词： multiway data analysis nonnegative Tucker decomposition flexible clustering accelerated proximal gradient

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Collaborative positioning for swarms:A brief survey of vision,LiDAR and wireless sensors based methods

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Defence Technology（防务技术） 2024年第3期33卷 475-493页

作者： Zeyu Li Changhui Jiang xiaobo gu Ying Xu Feng zhou Jianhui Cui College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao266590China Geoloc Laboratory Universite Gustave EiffelParis77454France School of Automation Guangdong University of TechnologyGuangzhou510006China

As positioning sensors,edge computation power,and communication technologies continue to develop,a moving agent can now sense its surroundings and communicate with other *** receiving spatial information from both its environment and other agents,an agent can use various methods and sensor types to localize *** its high flexibility and robustness,collaborative positioning has become a widely used method in both military and civilian *** paper introduces the basic fundamental concepts and applications of collaborative positioning,and reviews recent progress in the field based on camera,LiDAR(Light Detection and Ranging),wireless sensor,and their *** paper compares the current methods with respect to their sensor type,summarizes their main paradigms,and analyzes their evaluation ***,the paper discusses the main challenges and open issues that require further research.

关键词： Collaborative positioning Vision LiDAR Wireless sensors Sensor fusion

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Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat

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Journal of Integrative Agriculture 2024年第5期23卷 1523-1540页

作者： Zhikai Cheng xiaobo gu Yadan Du Zhihui Zhou Wenlong Li xiaobo Zheng Wenjing Cai Tian Chang Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid AreasMinistry of Education/Northwest A&F University Yangling712100China

In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter *** on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral *** machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried *** results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth *** accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of *** purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral *** results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching.

关键词： mulched winter wheat machine learning fuzzy comprehensive evaluation comprehensive growth evaluation index unmanned aerial vehicle

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A Phytophthora sojae gene of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) induced in host infection and its anti-oxidative function in yeast

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Chinese Science Bulletin 2006年第11期51卷 1316-1323页

作者： ZENG Juan WANG Yuanchao SHEN gu ZHENG xiaobo Department of Plant Pathology Nanjing Agricultural University Nanjing 210095 China

Glyceraldehyde-3-phosphate dehydro- genase (GAPDH) is a multifunctional protein well defined in eukaryotes, especially in mammalian and Saccharomyces cerevisiae. Using the method of suppression subtractive hybridization (SSH), we identified a Phytophthora sojae cDNA coding GAPDH, which was up-regulated during the early stage of soybean infection. The termed PsGapdh gene pos- sessed three copies in the P. sojae genome. Its amino acid sequence harbored overall conserved domain of GADPH, homologous closest to GapC1 of Achlya bisexualis (oomycete) and adjoined to GapC2s of Odontella sinensis and Phaeodactylum tricornutum (diatom), on the C-Ⅱ branch of subfamily GapC in phylogeny tree of GAPDH. The transcrip- tional level of PsGapdh was up-regulated throughout early infection. Heterogenous expression of PsGapdh in the yeast tdh1-deleted mutant could rescue growth arrest under continuous exposure to H2O2. These results indicated active roles of PsGapdh in patho- gen-host interaction and anti-oxidation.

关键词：甘油醛磷酸盐脱氢酶 GAPDH 病原体-宿主相互作用抗氧化

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Synthesis and biological evaluation of ^(18)F-FB-NGA as a hepatic asialoglycoprotein receptor PET imaging agent

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Nuclear Science and Techniques 2013年第6期24卷 50-55页

作者： gu xiaobo CAI Gangming JIANG Mengjun ZHOU Yaoyuan ZHANG Rongjun Key Laboratory of Nuclear Medicine Ministry of HealthJiangsu Key Laboratory of Molecular Nuclear MedicineJiangsu Institute of Nuclear Medicine Department of Clinical Laboratory Science the First Wuxi Affiliated Hospital of Nanjing Medical UniversityWuxi Clinical Science Research Institute

Asialoglycoprotein receptor(ASGP-R)is a hepatic membrane receptor that uniquely exists on the surface of mammalian hepatocytes,and has been used as target of liver functional imaging agents for many *** labeled the Galactosyl-neoglycoalbumin(NGA)with 18F to get a PET molecular probe 18F-FB-NGA and evaluated its ability as a liver functional PET imaging *** 18F-FB-NGA was prepared with NGA by conjugation with Nsuccinimidyl-4-18F-fluorobenzoate(18F-SFB)and purified with PD-10 desalting *** radiolabeling yield and radiochemical purity of 18F-FB-NGA were determined by *** with 18F-F–,the total time for 18F-FB-NGA was about 120±10 *** decay-corrected radiochemical yield is about 25–30%.The radiochemical purity of purified 18F-FB-NGA was more than 98%.Labeled with 185–1850 MBq 18F-SFB,the specific activity of 18F-FBNGA was estimated to be 7.83–78.3 TBq/*** of 18F-FB-NGA in normal mice was investigated after injection through the tail *** results showed that the liver accumulated 39.47±3.42 and 12.12±6.11%ID/g at 10 and 30 min after injection,*** MicroPET images in mice were acquired with and without block after injection of the radiotracer,*** liver activity accumulation was observed at 5 min after injection in normal *** the contrary,the liver accumulation was significantly lower after block,indicating the specific binding to ASGP-R.18F-FB-NGA is probably a potential PET liver imaging agent.

关键词：去唾液酸糖蛋白受体细胞膜受体肝功能 PET 显像剂生物学评价放射化学纯度放射性标记

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STUDIES OF DISSOLVED OXYGEN IN PRODUCTION OF D-RIBOSE BY FERMENTATION

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化工学报 2000年第S1期51卷 280-282页

作者： Wang Changlu, gu xiaobo, Hao Jian, Du Lianxiang and Zhao Xueming (Tianjin University of Light Industry, Tianjin 300222, Tianjin University, Tianjin 300072)

This paper mainly dealt with the dissolved oxygen in production of D-ribose by fermentation. The oxygen transfer coefficients of common flask, buffed flask and jar fermentor were determined.

关键词： buffed flask oxygen transfer coefficients D-ribose fermentation

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Effects of different ridge-furrow mulching systems on yield and water use efficiency of summer maize in the Loess Plateau of China

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Journal of Arid Land 2021年第9期13卷 947-961页

作者： CHEN Pengpeng gu xiaobo LI Yuannong QIAO Linran LI Yupeng FANG Heng YIN Minhua ZHOU Changming Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F UniversityYangling 712100China College of Art and Science Georgia State UniversityAtlanta 30341USA College of Water Conservancy and Hydropower Engineering Gansu Agricultural UniversityLanzhou 730070China College of Land Resources and Environment Jiangxi Agricultural UniversityNanchang 330045China

Ridge-furrow film mulching has been proven to be an effective water-saving and yield-improving planting pattern in arid and semi-arid *** is the main factor limiting the local agricultural production in the Loess Plateau of *** this study,we tried to select a suitable ridge-furrow mulching system to improve this situation.A two-year field experiment of summer maize(Zea mays L.)during the growing seasons of 2017 and 2018 was conducted to systematically analyze the effects of flat planting with no film mulching(CK),ridge-furrow with ridges mulching and furrows bare(RFM),and double ridges and furrows full mulching(DRFFM)on soil temperature,soil water storage(SWS),root growth,aboveground dry matter,water use efficiency(WUE),and grain *** RFM and DRFFM significantly increased soil temperature in ridges,while soil temperature in furrows for RFM and DRFFM was similar to that for *** largest SWS was observed in DRFFM,followed by RFM and CK,with significant differences among *** was lower in ridges than in furrows for *** treatment kept soil water in ridges,resulting in higher SWS in ridges than in furrows after a period of no water *** the two growing seasons,compared with CK,RFM increased root mass by 10.2%and 19.3%at the jointing and filling stages,respectively,and DRFFM increased root mass by 7.9%at the jointing stage but decreased root mass by 6.0%at the filling *** the two growing seasons,root length at the jointing and filling stages was respectively increased by 75.4%and 58.7%in DRFFM,and 20.6%and 30.2%in *** to the jointing stage,the increased proportions of root mass and length at the filling stage were respectively 42.8%and 94.9%in DRFFM,63.2%and 115.1%in CK,and 76.7%and 132.1%in RFM,over the two growing seasons,showing that DRFFM slowed down root growth while RFM promoted root growth at the later growth *** treatment increased root mass and root length in ridges and decreased them in 0-30 cm

关键词： ridge-furrow mulching summer maize soil water storage soil temperature root mass root length

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小型饱和汽轮机叶片抗冲蚀保护方法对比试验研究

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机械工程学报 2006年第1期42卷 231-238页

作者：姚寿广顾晓波张小卫江苏科技大学机械与动力工程学院镇江212003

在多方案的热力设计计算和分析比较的基础上,建立了适用于小型饱和汽轮机叶片抗冲蚀性能对比试验的热态试验装置。在对汽轮机叶片表面处理工艺进行初步研究的基础上,对不同表面处理后的小型饱和汽轮机叶片试样进行了热态冲蚀试验。通过... 详细信息

在多方案的热力设计计算和分析比较的基础上,建立了适用于小型饱和汽轮机叶片抗冲蚀性能对比试验的热态试验装置。在对汽轮机叶片表面处理工艺进行初步研究的基础上,对不同表面处理后的小型饱和汽轮机叶片试样进行了热态冲蚀试验。通过失重法和同位素法两种冲蚀量评价方法对试验结果进行性能对比评定,并通过金相和电镜分析以及化学腐蚀试验对试样的显微组织和微观形貌进行了详细分析,确认了激光相变淬火工艺相对于其他表面处理方案具有更好的耐冲蚀性能。

关键词：汽轮机叶片抗冲蚀表面处理

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