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Early-season crop type mapping using 30-m reference time series

Journal of Integrative Agriculture 2020年第7期19卷 1897-1911页

作者： hao peng-yu TANG Hua-jun CHEN Zhong-xin MENG Qing-yan KANG yu-peng Key Laboratory of Agricultural Remote Sensing Minstry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agrcultural SciencesBejing 100081P.R China Shenzhen Key Laboratory for Geo-Environmental Monitoring of Coastal Zone of the National Administration of Surveying Mapping and Geo-Information&Shenzhen Key Laboratory of Spatial Smart Sensing and ServicesShenzhen UniversityShenzhen 518060P.R.China Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBejjing 100101P.R.China

Early-season crop type mapping could provide important information for crop growth monitoring and yield prediction,but the lack of ground-surveyed training samples is the main challenge for crop type *** reference time series based method(RBM)has been proposed to identify crop types without the use of ground-surveyed training samples,the methods are not suitable for study regions with small field size because the reference time series are mainly generated using data set with low spatial *** the combination of Landsat data and Sentinel-2 data could increase the temporal resolution of 30-m image time series,we improved the RBM by generating reference normalized difference vegetation index(NDVI)/enhanced vegetation index(EVI)time series at 30-m resolution(30-m RBM)using both Landsat and Sentinel-2 data,then tried to estimate the potential of the reference NDVI/EVI time series for crop identification at early *** a test case,we tried to use the 30-m RBM to identify major crop types in Hengshui,China at early season of 2018,the results showed that when the time series of the entire growing season were used for classification,overall classification accuracies of the 30-m RBM were higher than 95%,which were similar to the accuracies acquired using the ground-surveyed training *** addition,cotton,spring maize and summer maize distribution could be accurately generated 8,6 and 8 weeks before their harvest using the 30-m RBM;but winter wheat can only be accurately identified around the harvest time ***,NDVI outperformed EVI for crop type classification as NDVI had better separability for distinguishing crops at the green-up time *** with the previous RBM,advantage of 30-m RBM is that the method could use the samples of the small fields to generate reference time series and process image time series with missing value for early-season crop casification;while,samples collected from multiple years should be futher

关键词： early season Landsat Sentinel-2 reference time series crop classification Hengshui

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High resolution crop intensity mapping using harmonized Landsat-8 and Sentinel-2 data

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Journal of Integrative Agriculture 2019年第12期18卷 2883-2897页

作者： hao peng-yu TANG Hua-jun CHEN Zhong-xin yu Le WU Ming-quan Key Laboratory of Agricultural Remote Sensing Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China Key Laboratory for Geo-Environmental Monitoring of Coastal Zone of the National Administration of Surveying Mapping and Geo Information/Shenzhen Key Laboratory of Spatial Smart Sensing and ServicesShenzhen UniversityShenzhen 518060P.R.China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084P.R.China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101P.R.China

An increase in crop intensity could improve crop yield but may also lead to a series of environmental problems, such as depletion of ground water and increased soil salinity. The generation of high resolution(30 m) crop intensity maps is an important method used to monitor these changes, but this is challenging because the temporal resolution of the 30-m image time series is low due to the long satellite revisit period and high cloud coverage. The recently launched Sentinel-2 satellite could provide optical images at 10–60 m resolution and thus improve the temporal resolution of the 30-m image time series. This study used harmonized Landsat Sentinel-2(HLS) data to identify crop intensity. The sixth polynomial function was used to fit the normalized difference vegetation index(NDVI) and enhanced vegetation index(EVI) curves. Then, 15-day NDVI and EVI time series were then generated from the fitted curves and used to generate the extent of croplands. Lastly, the first derivative of the fitted VI curves were used to calculate the VI peaks;spurious peaks were removed using artificially defined thresholds and crop intensity was generated by counting the number of remaining VI peaks. The proposed methods were tested in four study regions, with results showing that 15-day time series generated from the fitted curves could accurately identify cropland extent. Overall accuracy of cropland identification was higher than 95%. In addition, both the harmonized NDVI and EVI time series identified crop intensity accurately as the overall accuracies, producer’s accuracies and user’s accuracies of non-cropland, single crop cycle and double crop cycle were higher than 85%. NDVI outperformed EVI as identifying double crop cycle fields more accurately.

关键词： crop inten sity time series sixth polyno mial fu nction harm on ized Lan dsat-8 and Sen tinel-2

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An immune-tabu hybrid algorithm for thermal unit commitment of electric power systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第6期10卷 877-889页

作者： Wei LI hao-yu peng Wei-hang ZHU De-ren SHENG Jian-hong CHEN School of Mechanical and Energy Engineering Zhejiang University Hangzhou 310027 China Department of Industrial Engineering Lamar University Beaumont 77710-0032 USA

This paper presents a new method based on an immune-tabu hybrid algorithm to solve the thermal unit commitment （TUC） problem in power plant optimization. The mathematical model of the TUC problem is established by analyzing the generating units in modem power plants. A novel immune-tabu hybrid algorithm is proposed to solve this complex problem. In the algorithm, the objective function of the TUC problem is considered as an antigen and the solutions are considered as antibodies, which are determined by the affinity computation. The code length of an antibody is shortened by encoding the continuous operating time, and the optimum searching speed is improved. Each feasible individual in the immune algorithm （IA） is used as the initial solution of the tabu search （TS） algorithm after certain generations of IA iteration. As examples, the proposed method has been applied to several thermal unit systems for a period of 24 h. The computation results demonstrate the good global optimum searching performance of the proposed immune-tabu hybrid algorithm. The presented algorithm can also be used to solve other optimization problems in fields such as the chemical industry and the power industry.

关键词： Immune algorithm (IA) Tabu search (TS) Optimization method Unit commitment

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Radiomics of rectal cancer for predicting distant metastasis and overall survival

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World Journal of Gastroenterology 2020年第33期26卷 5008-5021页

作者： Mou Li yu-Zhou Zhu Yong-Chang Zhang yu-Feng yue hao-peng yu Bin Song Department of Radiology West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Gastrointestinal Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Radiology Chengdu Seventh People’s HospitalChengdu 610213Sichuan ProvinceChina

BACKGROUND Rectal cancer(RC)patient stratification by different factors may yield variable ***,more efficient prognostic biomarkers are needed for improved risk stratification,personalized treatment,and prognostication of RC *** To build a novel model for predicting the presence of distant metastases and 3-year overall survival(OS)in RC *** This was a retrospective analysis of 148 patients(76 males and 72 females)with RC treated with curative resection,without neoadjuvant or postoperative chemoradiotherapy,between October 2012 and December *** patients were allocated to a training or validation set,with a ratio of 7:*** features were extracted from portal venous phase computed tomography(CT)images of *** least absolute shrinkage and selection operator regression analysis was used for feature *** logistic regression analysis was used to develop the radiomics signature(Rad-score)and the clinicoradiologic risk model(the combined model).Receiver operating characteristic curves were constructed to evaluate the diagnostic performance of the models for predicting distant metastasis of *** association of the combined model with 3-year OS was investigated by Kaplan-Meier survival *** A total of 51(34.5%)patients had distant metastases,while 26(17.6%)patients died,and 122(82.4%)patients lived at least 3 years *** values of both the Rad-score(consisted of three selected features)and the combined model were significantly different between the distant metastasis group and the nonmetastasis group(0.46±0.21 vs 0.32±0.24 for the Rad-score,and 0.60±0.23 vs 0.28±0.26 for the combined model;P<0.001 for both models).Predictors contained in the combined model included the Rad-score,pathological N-stage,and *** addition of histologic grade to the model failed to show incremental prognostic *** combined model showed good discrimination,with areas under the curve of 0.842 and

关键词： Radiomics Rectal cancer Overall survival Distant metastasis Computed tomography

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Follicular lymphoma presenting like marginal zone lymphoma:A case report

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World Journal of Clinical Cases 2022年第17期10卷 5877-5883页

作者： hao-yu peng Ying-Jie Xiu Wei-Hong Chen Qing-Li Gu Xin Du Department of Hematology Shenzhen Second People’s HospitalThe First Affiliated Hospital of Shenzhen UniversityShenzhen 518035Guangdong ProvinceChina Department of Pathology Shenzhen Second People’s HospitalThe First Affiliated Hospital of Shenzhen UniversityShenzhen 518035Guangdong ProvinceChina

BACKGROUND Follicular lymphoma(FL),a common type of indolent lymphoma,carries markers of the germinal center,and the rearrangement of the BCL-2 gene is regarded as an initiating event and a hallmark of the *** FL has marginal zone differentiation,some marginal zone features are carried by the *** SUMMARY A 54-year-old male with lymphadenopathy,splenomegaly and hyperlymphocytosis was diagnosed with FL with marginal zone *** tumor demonstrated different features in the bone marrow(BM)compared with the follicle of the lymph node(LN).Some component of the neoplasm mimicked marginal zone lymphoma,such as infiltrating the marginal zone of the LN,displaying a monocytoid shape and lacking the expression of CD10 in the *** diagnosis of FL was made due to the concurrent detection of BCL-2 rearrangement in the LN and *** Discordant pathological features in LN and BM could mislead *** clinical and pathological manifestations are confusing in diagnosis,typical genetic abnormalities are decisive.

关键词： Follicular lymphoma Marginal zone differentiation Discordant immunophenotypes Gene rearrangement Case report

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Deep Learning and Tensor-Based Multiple Clustering Approaches for Cyber-Physical-Social Applications

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Computers, Materials & Continua 2024年第3期78卷 4109-4128页

作者： Hongjun Zhang hao Zhang yu Lei hao Ye peng Li Desheng Shi School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing210023China China Communications Services Co. Ltd.Beijing100071China China Communications Services Hexin Science&Technology Co. Ltd.Hefei230031China

The study delves into the expanding role of network platforms in our daily lives, encompassing various mediums like blogs, forums, online chats, and prominent social media platforms such as Facebook, Twitter, and Instagram. While these platforms offer avenues for self-expression and community support, they concurrently harbor negative impacts, fostering antisocial behaviors like phishing, impersonation, hate speech, cyberbullying, cyberstalking, cyberterrorism, fake news propagation, spamming, and fraud. Notably, individuals also leverage these platforms to connect with authorities and seek aid during disasters. The overarching objective of this research is to address the dual nature of network platforms by proposing innovative methodologies aimed at enhancing their positive aspects and mitigating their negative repercussions. To achieve this, the study introduces a weight learning method grounded in multi-linear attribute ranking. This approach serves to evaluate the significance of attribute combinations across all feature spaces. Additionally, a novel clustering method based on tensors is proposed to elevate the quality of clustering while effectively distinguishing selected features. The methodology incorporates a weighted average similarity matrix and optionally integrates weighted Euclidean distance, contributing to a more nuanced understanding of attribute importance. The analysis of the proposed methods yields significant findings. The weight learning method proves instrumental in discerning the importance of attribute combinations, shedding light on key aspects within feature spaces. Simultaneously, the clustering method based on tensors exhibits improved efficacy in enhancing clustering quality and feature distinction. This not only advances our understanding of attribute importance but also paves the way for more nuanced data analysis methodologies. In conclusion, this research underscores the pivotal role of network platforms in contemporary society, emp

关键词： Network platform tensor-based clustering weight learning multi-linear euclidean

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CRISPR-Cas系统在食源性致病菌检测中的研究进展

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食品安全质量检测学报 2024年第8期15卷 154-163页

作者：郭浩宇王瑞曦秦琳琳王邵天于淏芃赵枳熒尹丹阳马龙天津科技大学生物工程学院食品营养与安全国家重点实验室天津300457 天津科技大学艺术设计学院天津300457

食源性致病菌的快速检测对预防食源性疾病的爆发具有重要意义。成簇规律间隔短回文重复序列(clustered regularly interspaced short palindromicrepeats,CRISPR)及CRISPR相关蛋白(CRISPR-associated protein,Cas)构成的CRISPR-Cas系统已被广泛的应用于核酸检测,并在对食源性致病菌的检测中展现出快速、灵敏度高、特异性强等优势。本文介绍了CRISPR-Cas系统的原理、机制,总结了CRISPR-Cas系统与不同扩增方法和信号输出模式相结合在食源性致病菌检测中的应用,并讨论了这些检测方法存在的一些问题和挑战,最后对该技术的未来发展前景进行展望,旨在为食源性致病菌的快速检测提供新思路。

关键词：成簇规律间隔短回文重复序列相关蛋白食源性致病菌核酸检测

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Advancements in machine learning for material design and process optimization in the field of additive manufacturing

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China Foundry 2024年第2期21卷 101-115页

作者： hao-ran Zhou hao Yang Huai-qian Li Ying-chun Ma Sen yu Jian shi Jing-chang Cheng peng Gao Bo yu Zhi-quan Miao Yan-peng Wei National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China School of Materials Science and Engineering Nanyang Technological University639798Singapore

Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric ***,the development of additive manufacturing process is constrained by issues like unclear fundamental principles,complex experimental cycles,and high *** learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new *** paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process ***,it introduces the background and significance of machine learning-assisted design in additive manufacturing *** then further delves into the application of machine learning in additive manufacturing,focusing on model design and process ***,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing.

关键词： additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning

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A hybrid machine learning optimization algorithm for multivariable pore pressure prediction

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Petroleum Science 2024年第1期21卷 535-550页

作者： Song Deng hao-yu Pan Hai-Ge Wang Shou-Kun Xu Xiao-peng Yan Chao-Wei Li Ming-Guo peng hao-Ping peng Lin Shi Meng Cui Fei Zhao School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou213164JiangsuChina Tubular Goods Research Institute of CNPC Beijing102249China CNPC Engineering Technology R&D Company Limited Beijing102206China

Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling *** methods for predicting pore pressure are limited when forming particular structures and *** this paper,a machine learning algorithm and effective stress theorem are used to establish the transformation model between rock physical parameters and pore *** study collects data from three *** 1 had 881 data sets for model training,and Wells 2 and 3 had 538 and 464 data sets for model *** this paper,support vector machine(SVM),random forest(RF),extreme gradient boosting(XGB),and multilayer perceptron(MLP)are selected as the machine learning algorithms for pore pressure *** addition,this paper uses the grey wolf optimization(GWO)algorithm,particle swarm optimization(PSO)algorithm,sparrow search algorithm(SSA),and bat algorithm(BA)to establish a hybrid machine learning optimization algorithm,and proposes an improved grey wolf optimization(IGWO)*** IGWO-MLP model obtained the minimum root mean square error(RMSE)by using the 5-fold cross-validation method for the training *** the pore pressure data in Well 2 and Well 3,the coefficients of determination(R^(2))of SVM,RF,XGB,and MLP are 0.9930 and 0.9446,0.9943 and 0.9472,0.9945 and 0.9488,0.9949 and *** achieves optimal performance on both training and test data,and the MLP model shows a high degree of *** indicates that the IGWO-MLP is an excellent predictor of pore pressure and can be used to predict pore pressure.

关键词： Pore pressure Grey wolf optimization Multilayer perceptron Effective stress Machine learning

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Direct ink writing of multifunctional gratings with gel-like MXene/norepinephrine ink for dynamic electromagnetic interference shielding and patterned Joule heating

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Nano Research 2024年第3期17卷 1585-1594页

作者： Pei-Zhu Jiang Zhiming Deng peng Min Lvxuan Ye Cheng-Zhang Qi hao-yu Zhao Ji Liu hao-Bin Zhang Zhong-Zhen yu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China School of Chemistry CRANN and AMBERTrinity College DublinDublin D02PN40Ireland

Intelligent electromagnetic interference(EMI)shielding modulators with a wide tuning range and cyclic stability are urgently needed but their fabrication remains challenging.A gel-like MXene/norepinephrine ink is developed and multifunctional MXene gratings with wide EMI shielding effectiveness(SE)tuning range,superior reversibility,and high mechanical flexibility are constructed by direct ink writing approach for dynamic EMI shielding and patterned Joule heating *** modulable MXene/norepinephrine grating with a high conductivity of 3510 S·cm-1 can conveniently realize the seamless modulation of the EMI SE by adjusting the angle between the MXene grating filaments and the electric field of the incident electromagnetic waves,offering highly reversible switching between shielding“On”(28.0 dB)and“Off”(0.5 dB)***,due to the optimized integration of the MXene ink and the rationally designed pattern,a superior specific EMI SE of 95,688.2 dB·cm^(2)·g^(-1) is achieved in the“On”***,the MXene/norepinephrine ink can be used to fabricate many complex patterned gratings with superior stability,instant responsibility,and superb mechanical flexibility,exhibiting a unique patterned Joule heating *** writing of multifunctional gratings paves a means for developing intelligent EMI shielding materials,wearable electronic devices,and advanced thermal management materials.

关键词： MXene ink direct ink writing electromagnetic interference shielding multifunctional gratings Joule heating

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