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304篇 您的检索式:作者名="Xiaoxuan"
    题名 作者 年代 出处 被引量
1Antibacterial and angiogenic chitosan microneedle array patch for promoting wound healing显示文摘A patch with the capability of avoiding wound infection and promoting tissue remolding is of great value for wound healing.In this paper,we develop a biomass chitosan microneedle array(CSMNA)patch integrated with smart responsive drug delivery for promoting wound healing.Chitosan possesses many outstanding features such as the natural antibacterial property and has been widely utilized for wound healing.Besides,the microstructure of microneedles enables the effective delivery of loaded drugs into the target area and avoids the excessive adhesion between the skin and the patch.Also,vascular endothelial growth factor(VEGF)is encapsulated in the micropores of CSMNA by temperature sensitive hydrogel.Therefore,the smart release of the drugs can be controllably realized via the temperature rising induced by the inflammation response at the site of wounds.It is demonstrated that the biomass CSMNA patch can promote inflammatory inhibition,collagen deposition,angiogenesis,and tissue regeneration during the wound closure.Thus,this versatile CSMNA patch is potentially valuable for wound healing in clinical applications.Junjie Chi Xiaoxuan Zhang Canwen Chen Changmin Shao Yuanjin Zhao Yongan Wang 2020Bioactive Materials2020,5,2:25
2Root microbiota shift in rice correlates with resident time in the field and developmental stage显示文摘Land plants in natural soil form intimate relationships with the diverse root bacterial microbiota. A growing body of evidence shows that these microbes are important for plant growth and health. Root microbiota composition has been widely studied in several model plants and crops; however, little is known about how root microbiota vary throughout the plant's life cycle under field conditions. We performed longitudinal dense sampling in field trials to track the time-series shift of the root microbiota from two representative rice cultivars in two separate locations in China. We found that the rice root microbiota varied dramatically during the vegetative stages and stabilized from the beginning of the reproductive stage, after which the root microbiota underwent relatively minor changes until rice ripening. Notably, both rice genotype and geographical location influenced the patterns of root microbiota shift that occurred during plant growth. The relative abundance of Deltaproteobacteria in roots significantly increased overtime throughout the entire life cycle of rice, while that of Betaproteobacteria, Firmicutes, and Gammaproteobacteria decreased. By a machine learning approach, we identified biomarker taxa and established a model to correlate root microbiota with rice resident time in the field(e.g., Nitrospira accumulated from 5 weeks/tillering in field-grown rice). Our work provides insights into the process of rice root microbiota establishment.Jingying Zhang Na Zhang Yong-Xin Liu Xiaoning Zhang Bin Hu Yuan Qin Haoran Xu Hui Wang Xiaoxuan Guo Jingmei Qian Wei Wang Pengfan Zhang Tao Jin Chengcai Chu Yang Bai 2018Science China(Life Sciences)2018,61,6:24
3The first all-season sample set for mapping global land cover with Landsat-8 data显示文摘We report the world's first all-season training and validation sample sets for global land cover classification with Landsat-8 data.Prior to this,such samples were only available at a single date primarily from the growing season.It is unknown how much limitation such a single-date sample has to mapping global land cover in other seasons of the year.To answer this question,we selected available Landsat-8 images from four seasons and collected training and validation samples from them.We compared the performances of training samples in different seasons using Random Forest algorithm.We found that the use of training samples from any individual season would result in the best overall classification accuracy when validated by samples in the same season.The global overall accuracy from combined best seasonal results was 67.2% when classifying the 11 Level-1 classes in the Finer Resolution Observation and Monitoring of Global Land Cover(FROM-GLC) classification system.The use of training samples from all seasons(named all-season training sample set hereafter) produced an overall accuracy of 67.0%.We also tested classification within 10° latitude 60° longitude zones using all-season training subsample within each zone and obtained an overall accuracy of 70.2%.This indicates that properly grouped subsamples in space can help improve classification accuracies.All the results in this study seem to suggest that it is possible to use an all-season training sample set to reach global optimality with universal applicability in classifying images acquired at any time of a year for global land cover mapping.Congcong Li Peng Gong Jie Wang Zhiliang Zhu Gregory S. Biging Cui Yuan Tengyun Hu Haiying Zhang Qi Wang Xuecao Li Xiaoxuan Liu Yidi Xu Jing Guo Caixia Liu Kwame O. Hackman Meinan Zhang Yuqi Cheng Le Yu Jun Yang Huabing Huang Nicholas Clinton 2017Science Bulletin2017,62,7:21
4A practical guide to amplicon and metagenomic analysis of microbiome data显示文摘Advances in high-throughput sequencing(HTS)have fostered rapid developments in the field of microbiome research,and massive microbiome datasets are now being generated.However,the diversity of software tools and the complexity of analysis pipelines make it difficult to access this field.Here,we systematically summarize the advantages and limitations of microbiome methods.Then,we recommend specific pipelines for amplicon and metagenomic analyses,and describe commonly-used software and databases,to help researchers select the appropriate tools.Furthermore,we introduce statistical and visualization methods suitable for microbiome analysis,including alpha-and betadiversity,taxonomic composition,difference comparisons,correlation,networks,machine learning,evolution,source tracing,and common visualization styles to help researchers make informed choices.Finally,a stepby-step reproducible analysis guide is introduced.We hope this review will allow researchers to carry out data analysis more effectively and to quickly select the appropriate tools in order to efficiently mine the biological significance behind the data.Yong-Xin Liu Yuan Qin Tong Chen Meiping Lu Xubo Qian Xiaoxuan Guo Yang Bai 2021Protein & Cell2021,12,5:20
5Polygonisation of railway wheels:a critical review显示文摘Polygonisation is a common nonuniform wear phenomenon occurring in railway vehicle wheels and has a severe impact on the vehicle–track system,ride comfort,and lineside residents.This paper first summarizes periodic defects of the wheels,including wheel polygonisation and wheel corrugation,occurring in railways worldwide.Thereafter,the effects of wheel polygonisation on the wheel–rail interaction,noise and vibration,and fatigue failure of the vehicle and track components are reviewed.Based on the different causes,the formation mechanisms of periodic wheel defects are classified into three categories:(1)initial defects of wheels,(2)natural vibration of the vehicle–track system,and(3)thermoelastic instability.In addition,the simulation methods of wheel polygonisation evolution and countermeasures to mitigate wheel polygonisation are presented.Emphasis is given to the characteristics,effects,causes,and solutions of wheel polygonisation in metro vehicles,locomotives,and highspeed trains in China.Finally,the guidance is provided on further understanding the formation mechanisms,monitoring technology,and maintenance criterion of wheel polygonisation.Gongquan Tao Zefeng Wen Xuesong Jin Xiaoxuan Yang 2020Railway Engineering Science2020,28,4:20
6Hierarchical method of task assignment for multiple cooperating UAV teams显示文摘The problem of task assignment for multiple cooperating unmanned aerial vehicle(UAV) teams is considered. Multiple UAVs forming several small teams are needed to perform attack tasks on a set of predetermined ground targets. A hierarchical task assignment method is presented to address the problem. It breaks the original problem down to three levels of sub-problems: target clustering, cluster allocation and target assignment. The first two sub-problems are centrally solved by using clustering algorithms and integer linear programming, respectively, and the third sub-problem is solved in a distributed and parallel manner, using a mixed integer linear programming model and an improved ant colony algorithm. The proposed hierarchical method can reduce the computational complexity of the task assignment problem considerably, especially when the number of tasks or the number of UAVs is large. Experimental results show that this method is feasible and more efficient than non-hierarchical methods.Xiaoxuan Hu Huawei Ma Qingsong Ye He Luo 2015Journal of Systems Science & Complexity2015,28,5:14
7Bioinspired Adhesive and Antibacterial Microneedles for Versatile Transdermal Drug Delivery显示文摘Microneedles have attracted increasing interest among various medical fields due to their painless,noninvasive,and efficient way of drug delivery.However,practical applications of these microneedles in different epidermal locations and environments are still restricted by their low adhesion and poor antimicrobial activity.Here,inspired by the antibacterial strategy of Paenibacillus polymyxa and adhesion mechanisms of mussel byssi and octopus tentacles,we develop hierarchical microneedles with multifunctional adhesive and antibacterial abilities.With polydopamine hydrogel as the microneedle base and a loop of suctioncup-structured concave chambers encircling each microneedle,the generated microneedles can fit the skin well;keep strong adhesion in dry,moist,and wet environments;and realize self-repair after being split into two parts.Besides,as polymyxin is loaded into both the hydrogel tips and the polydopamine base,the microneedles are endowed with excellent ability to resist common bacteria during storage and usage.We have demonstrated that these microneedles not only showed excellent adhesion when applied to knuckles and ideal antibacterial activity but also performed well in drug-sustained release and treatment for the osteoarthritis rat model.These results indicate that bioinspired multifunctional microneedles will break through the limitation of traditional methods and be ideal candidates for versatile transdermal drug delivery systems.Xiaoxuan Zhang Guopu Chen Yunru Yu Lingyu Sun Yuanjin Zhao 2020Research2020,,1:14
8Microfluidic Generation of Microsprings with Ionic Liquid Encapsulation for Flexible Electronics显示文摘Inspired by helical or spiral veins,which endow plants with excellent fexibility and elasticity to withstand storms,we present novel hollow microsprings with ionic liquid encapsulation for fexible and stretchable electronics.Te microsprings were generated by using a coaxial capillary microfuidic device to consecutively spin poly(vinylidene fuoride)(PVDF)presolution and an ionic liquid,which formed laminar fows in the coaxial injection microfuidic channels.Te fast phase inversion of PVDF helps to form the core-shell structure of a microfber and guarantees the in situ encapsulation of ionic liquid.Te hybrid microfber can then spiral and be further solidifed to maintain the helical structure with increasing fow rates of the injection fuids.Because of the feasible and precise control of the injection fuids during the microfuidic spinning,the resultant microsprings have controlled core-shell structures,helical pitches,and corresponding electromechanical properties.By further embedding them into stretchable flms,the simple paradigm of a fexible device shows great conductive performance in tensile tests and even motion cycles,which could be explored as a promising candidate in stretchable sensors,fexible electronics,and electronic skins.Yunru Yu Jiahui Guo Lingyu Sun Xiaoxuan Zhang Yuanjin Zhao 2019Research2019,,1:14
9An Arabidopsis ABC Transporter Mediates Phosphate Deficiency-Induced Remodeling of Root Architecture by Modulating Iron Homeostasis in Roots显示文摘改变根建筑学是到磷酸盐(Pi ) 的植物的主要发展回答缺乏并且被认为在表层土为可得到的 Pi 提高一个植物能力到牧草。然而,控制这回答的内在的机制糟糕被理解。在这研究,我们识别了 Arabidopsis 异种, hps10 (对 Pi 饥饿 10 过分敏感) ,它在 Pi 足够的状况下面是词法上正常的,但是在 Pi 下面显示出主要的根生长和侧面的根的提高的生产的增加的抑制缺乏。hps10 是 ALUMINUM SENSITIVE3 (ALS3 ) 基因的以前识别的等位基因(als3-3 ) ,它涉及植物忍耐到铝毒性。我们的结果证明 ALS3 和它的交往的蛋白质 AtSTAR1 在 tonoplast 形成 ABC transporter 建筑群。这蛋白质建筑群调停一高度在 Xenopus 卵母细胞的 electrogenic 运输。在 Pi 缺乏下面, als3 比野类型在它的根积累 Fe 3+ 的高水平。在 Arabidopsis, LPR1 (低磷酸盐 ROOT1 ) 和 LPR2 编码 ferroxidases,当变异时,它在根和原因根生长减少 Fe 3+ 累积对 Pi 缺乏感觉迟钝。这里,我们提供证明 ALS3 与 LPR1/2 合作调整 Pi 的引人注目的证据在根的由 modulating Fe 动态平衡的根建筑学的导致缺乏的改变。Jinsong Dong Miguel A. PiSeros Xiaoxuan Li Haibing Yang Yu Liu Angus S. Murphy Leon V. Kochian Dong Liu 2017Molecular Plant2017,10,2:13
10Annual 30-m land use/land cover maps of China for 1980–2015 from the integration of AVHRR, MODIS and Landsat data using the BFAST algorithm显示文摘Annual land use land cover(LULC)change information at medium spatial resolution(i.e.at 30 m)is required in numerous subjects,such as biophysical modelling,land management and global change studies.Annual LULC information,however,is usually not available at continental or national scale due to reasons such as insufficient remote sensing data coverage or lack of computational capabilities.Here we integrate high temporal resolution and coarse spatial resolution satellite images(i.e.,Moderate Resolution Imaging Spectroradiometer(MODIS)and Global Inventory Modelling and Mapping Studies(GIMMS)normalized difference vegetation index(NDVI))with high spatial resolution datasets(China’s Land-Use/cover Datasets(CLUDs)derived from 30-meter Landsat TM/ETM+/OLI)to generate reliable annual nominal 30 m LULC maps for the whole of China between 1980 and 2015.We also test the performance of a statistical based change detection algorithm(Breaks for Additive Seasonal and Trend),originally designed for tracking forest change,in classifying all-type LULC change.As a result,a nominal 30 m annual land use/land cover datasets(CLUD-A)from 1980 to 2015 was developed for the whole China.The mapping results were assessed with a change sample dataset,a regional annual validation sample set and a three-year China sample set.Of the detected change years,75.61%matched the exact time of conversion within±1 year.Annual mapping results provided a detail process of urbanization,deforestation,afforestation,water and cropland dynamics over the past 36 years.The consistent characterization of land change dynamics for China can be further used in scientific research and to support land management for policy-makers.Yidi XU Le YU Dailiang PENG Jiyao ZHAO Yuqi CHENG Xiaoxuan LIU Wei LI Ran MENG Xinliang XU Peng GONG 2020Science China Earth Sciences2020,63,9:12
11Bio-inspired clamping microneedle arrays from flexible ferrofluid-configured moldings显示文摘Microneedle(MN)arrays have demonstrated value for cosmetics,diagnosis,transdermal drug delivery,and other biomedical areas.Much effort has been devoted to developing simple stratagem for creating versatile moldings and generating functional MN arrays.Here,inspired by the serrated microstructure of mantises’forelegs,we present a novel serration-like clamping MN array based on ferrofluidconfigured moldings.Benefiting from the flexibility and versatility of ferrofluids,negative microhole array moldings with various sizes and angles toward the midline could be created easily.The corresponding biocompatible polymer MN arrays with both isotropic and anisotropic structures could then be produced feasibly and cost-effectively by simply replicating these moldings.It was found that the resultant serrated clamping MN arrays had the ability to adhere to skin firmly,enabling them to be used over a relatively long time and while the recipient was moving.This proposed technology performed well in minimally invasive drug administration and sustained glucocorticoids release during treatment for imiquimod-induced psoriasis in mice.These features indicated that such MN arrays could play important roles in wearable transdermal drug delivery systems and in other applications.Xiaoxuan Zhang Fengyuan Wang Yunru Yu Guopu Chen Luoran Shang Lingyu Sun Yuanjin Zhao 2019Science Bulletin2019,64,15:11
12Stem cell transplantation for treatment of cerebral ischemia in rats Effects of human umbilical cord blood stem cells and human neural stem cells显示文摘BACKGROUND: Exogenous neural stem cell transplantation promotes neural regeneration. However, various types of stem cells transplantation outcomes remain controversial. OBJECTIVE: To explore distribution, proliferation and differentiation of human neural stem cells (hNSCs) and human umbilical cord blood stem cells (hUCBSCs) following transplantation in ischemic brain tissue of rats, and to compare therapeutic outcomes between hNSCs and hUCBSCs. DESIGN, TIME AND SETTING: Randomized controlled animal studies were performed at the Experimental Animal Center of Nanjing Medical University and Central Laboratory of Second Affiliated Hospital of Nanjing Medical University of China from September 2008 to April 2009. MATERIALS: hNSCs were harvested from brain tissue of 10-13 week old fetuses following spontaneous abortion, and hUCBSCs were collected from umbilical cord blood of full-term newborns at the Second Affiliated Hospital of Nanjing Medical University of China. hNSCs and hUCBSCs were labeled by 5-bromodeoxyuridine (BrdU) prior to transplantation. METHODS: Rat models of cerebral ischemia were established by the suture method. A total of 60 healthy male Sprague Dawley rats aged 7-9 weeks were randomly assigned to hNSC transplantation, hUCBSC transplantation and control groups. The rat models in the hNSC transplantation, hUCBSC transplantation and control groups were infused with hNSC suspension, hUCBSC suspension and saline via the caudal vein, respectively. MAIN OUTCOME MEASURES: The distribution, proliferation and differentiation of hNSCs and hUCBSCs in ischemic brain tissue were observed using immunohistochemical methods. Neurological function in rats was assessed using the neurological severity score. RESULTS: The number of BrdU-positive cells was significantly greater in the hNSC transplantation group compared with hUCBSC transplantation group at 14 days following transplantation (P < 0.05). The number of BrdU-positive cells reached a peak at 28 days following transplantation. Nestin-positive, glial fibrillary acidic protein-positive, cyclic nucleotide 3' phosphohydrolase-positive and neuron specific enolase-positive cells were visible following transplantation. No significant difference was determined in the constituent ratio of various cells between hNSC and hUCBSC transplantation groups (P > 0.05). The neurological severity score was significantly decreased in rats at 21 days following transplantation (P < 0.05). No significant difference was detected in neurological severity score between hNSC and hUCBSC transplantation groups at various time points (P > 0.05). CONCLUSION: The transplanted hNSCs and hUCBSCs can migrate into ischemic brain tissue, proliferate and differentiate into neuron-like, astrocyte-like and oligodendrocyte-like cells, and improve neurological function in rats with cerebral ischemia.Fenghua Pan Xinsheng Ding Haixia Ding Weimin Zhang Xiaoxuan Deng Juan Yao 2010Neural Regeneration Research2010,5,7:10
13Mechanisms of inclusion evolution and intra-granular acicular ferrite formation in steels containing rare earth elements显示文摘Inclusion characteristic and microstructure of rare earth (RE) elements containing steel were evaluated with scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), element-mapping, optical microscopy (OM), and automated feature analysis (AFA) option equipped with ASPEX PSEM. Factsage was used to calculate the equilibrium inclusion composition. Based on the calculation, an inclusion evolution mechanism was proposed. Furthermore, line scanning analysis was used to elucidate the intra-granular acicular ferrite (IAF) nucleation mechanism. The result showed that two different inclusions exist in sample steel: (Mn-Al-Si-Ti-La-Ce-O) +MnS complex inclusion and isolated MnS inclusion. Almost all nucleation sites for IAF are complex inclusions, while single MnS inclusion cannot induce IAF. A possible formation mechanism of complex inclusion is proposed based on calculated results using Factsage, which agrees well with experimental results. A Mn-depletion zone (MDZ) which exists adjacent to the (Mn-Al-Si-Ti-La-Ce-O) +MnS complex inclusion can account for the IAF formation. However, the low volume fraction (1.49×10-7) of effective inclusion may result in only 10% (volume fraction) IAF.Xiaoxuan DENG Min JIANG Xinhua WANG 2012Acta Metallurgica Sinica(English Letters)2012,25,3:9
14Optimal search for moving targets with sensing capabilities using multiple UAVs显示文摘This paper studies the problem of using multiple unmanned air vehicles(UAVs) to search for moving targets with sensing capabilities. When multiple UAVs(multi-UAV) search for a number of moving targets in the mission area, the targets can intermittently obtain the position information of the UAVs from sensing devices, and take appropriate actions to increase the distance between themselves and the UAVs. Aiming at this problem, an environment model is established using the search map, and the updating method of the search map is extended by considering the sensing capabilities of the moving targets. A multi-UAV search path planning optimization model based on the model predictive control(MPC) method is constructed, and a hybrid particle swarm optimization algorithm with a crossover operator is designed to solve the model. Simulation results show that the proposed method can effectively improve the cooperative search efficiency and can find more targets per unit time compared with the coverage search method and the random search method.Xiaoxuan Hu Yanhong Liu Guoqiang Wang 2017Journal of Systems Engineering and Electronics2017,28,3:8
15Compound Danshen tablets downregulate amyloid protein precursor mRNA expression in a transgenic cell model of Alzheimer's disease Effects and a comparison with donepezil显示文摘After gene mutation, the pcDNA3.1/APP595/596 plasmid was transfected into HEK293 cells to establish a cell model of Alzheimer's disease. The cell model was treated with donepezil or compound Danshen tablets after culture for 72 hours. Reverse transcription-PCR showed that the mRNA expression of amyloid protein precursor decreased in all groups following culture for 24 hours, and that there was no significant difference in the amount of decrease between donepezil and compound Danshen tablets. Our results suggest that compound Danshen tablets can reduce expression of the mRNA for amyloid protein precursor in a transgenic cell model of Alzheimer's disease, with similar effects to donepezil.Ren'an Qin Desheng Zhou Jiajun Wang Hua Hu Yang Yang Xiaoxuan Yao Xiaopeng Sun 2012Neural Regeneration Research2012,7,9:8
16Earth observation satellite scheduling for emergency tasks显示文摘The earth observation satellites(EOSs)scheduling problem for emergency tasks often presents many challenges.For example,the scheduling calculation should be completed in seconds,the scheduled task rate is supposed to be as high as possible,the disturbance measure of the scheme should be as low as possible,which may lead to the loss of important observation opportunities and data transmission delays.Existing scheduling algorithms are not designed for these requirements.Consequently,we propose a rolling horizon strategy(RHS)based on event triggering as well as a heuristic algorithm based on direct insertion,shifting,backtracking,deletion,and reinsertion(ISBDR).In the RHS,the driven scheduling mode based on the emergency task arrival and control station time window events are designed to transform the long-term,large-scale problem into a short-term,small-scale problem,which can improve the schedulability of the original scheduling scheme and emergency response sensitivity.In the ISBDR algorithm,the shifting rule with breadth search capability and backtracking rule with depth search capability are established to realize the rapid adjustment of the original plan and improve the overall benefit of the plan and early completion of emergency tasks.Simultaneously,two heuristic factors,namely the emergency task urgency degree and task conflict degree,are constructed to improve the emergency task scheduling guidance and algorithm efficiency.Finally,we conduct extensive experiments by means of simulations to compare the algorithms based on ISBDR and direct insertion,shifting,deletion,and reinsertion(ISDR).The results demonstrate that the proposed algorithm can improve the timeliness of emergency tasks and scheduling performance,and decrease the disturbance measure of the scheme,therefore,it is more suitable for emergency task scheduling.SUN Haiquan XIA Wei HU Xiaoxuan XU Chongyan 2019Journal of Systems Engineering and Electronics2019,30,5:8
17Biosynthetic pathway of terpenoid indole alkaloids in Catharanthus roseus显示文摘Catharanthus roseus 是最广泛地调查的药用的植物之一,它能生产超过 130 碱,包括强大的 antitumor 药 vinblastine 和长春新碱。这里,我们在 C 在 terpenoid 吲哚碱(TIA ) 的 biosynthetic 小径考察最近的进展。涉及这条小径的相应的酶的 roseus,和鉴定和描述。Strictosidine 是在不同 TIA 的生合成的中央中介,它被 secologanin 和 tryptamine 的冷凝作用形成。Secologanin 从 terpenoid (isoprenoid ) 被导出 biosynthetic 小径,当 tryptamine 从吲哚 biosynthetic 被导出时小径。然后各种各样的特定的结束产品被不同线路在下游的过程期间生产。尽管许多基因和相应的酶在这条小径被描绘了,我们整个 TIA biosynthetic 小径上的知识仍然保持大部分未知最新。TIA biosynthetic 小径的完整的说明是一个重要前提在药用的植物理解 TIA 生合成的规定并且由合成生物技术生产珍贵 TIA。Xiaoxuan Zhu Xinyi Zeng Chao Sun Shilin Chen 2014Frontiers of Medicine2014,8,3:8
18Selective elimination of chromophoric and fluorescent dissolved organic matter in a full-scale municipal wastewater treatment plant显示文摘Effluent organic matter(Ef OM) from municipal wastewater treatment plants potentially has a detrimental effect on both aquatic organisms and humans.This study evaluated the removal and transformation of chromophoric dissolved organic matter(CDOM) and fluorescent dissolved organic matter(FDOM) in a full-scale wastewater treatment plant under different seasons.The results showed that bio-treatment was found to be more efficient in removing bulk DOM(in term of dissolved organic carbon,DOC) than CDOM and FDOM,which was contrary to the disinfection process.CDOM and FDOM were selectively removed at various stages during the treatment.Typically,the low molecular weight fractions of CDOM and protein-like FDOM were more efficiently removed during bio-treatment process,whereas the humic-like FDOM exhibited comparable decreases in both bio-treatment and disinfection processes.Overall,the performance of the WWTP was weak in terms of CDOM and FDOM removal,resulting in enrichment of CDOM and FDOM in effluent.Moreover,the total removal of the bulk DOM(P < 0.05) and the protein-like FDOM(P < 0.05) displayed a significant seasonal variation,with higher removal efficiencies in summer,whereas removal of CDOM and the humic-like FDOM showed little differences between summer and winter.In all,the results provide useful information for understanding the fate and transformation of DOM,illustrating that sub-fractions of DOM could be selectively removed depending on treatment processes and seasonality.Xiaofang Yang Zhongbo Zhou Maddela Naga Raju Xiaoxuan Cai Fangang Meng 2017Journal of Environmental Sciences2017,29,7:6
19Multistate Degradation Model for Prognostics of Solder Joints Under Vibration Conditions显示文摘This paper develops a multistate degradation structure of the solder joints which can be used under various vibration conditions based on nonhomogeneous continuous-time hidden semi-Markov process.The parameters of the structure were estimated to illustrate the stochastic relationship between the degradation process and the monitoring indicator by using unsupervised learning methods.Random vibration tests on solder joints with different levels of power spectral density and fixed forms were conducted with a real time monitoring electrical resistance to examine the suitability of the model.It was experimentally verified that the multistate degradation structure matches the experimental process reasonably and accurately.Based on this multistate degradation model,the online prognostics of solder joint were analyzed and the results indicated that faults or failures can be detected timely,leading to appreciate maintenance actions scheduled to avoid catastrophic failures of electronics.TANG Wei JING Bo HUANG Yifeng SHENG Zengjin JIAO Xiaoxuan 2016Chinese Journal of Electronics2016,25,4:5
20Remaining useful life prediction based on variation coefficient consistency test of a Wiener process显示文摘High-cost equipment is often reused after maintenance, and whether the information before the maintenance can be used for the Remaining Useful Life(RUL) prediction after the maintenance is directly determined by the consistency of the degradation pattern before and after the maintenance.Aiming at this problem, an RUL prediction method based on the consistency test of a Wiener process is proposed.Firstly, the parameters of the Wiener process estimated by Maximum Likelihood Estimation(MLE) are proved to be biased, and a modified unbiased estimation method is proposed and verified by derivation and simulations.Then, the h statistic is constructed according to the reciprocal of the variation coefficient of the Wiener process, and the sampling distribution is derived.Meanwhile, a universal method for the consistency test is proposed based on the sampling distribution theorem, which is verified by simulation data and classical crack degradation data.Finally, based on the consistency test of the degradation model, a weighted fusion RUL prediction method is presented for the fuel pump of an airplane, and the validity of the presented method is verified by accurate computation results of real data, which provides a theoretical and practical guidance for engineers to predict the RUL of equipment after maintenance.Juan LI Bo JING Hongde DAI Xiaoxuan JIAO Xiaodong LIU 2018Chinese Journal of Aeronautics2018,31,1:5
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