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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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Cluster parallel rendering based on encoded mesh

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1124-1133页

作者： QIN Ai-hong XIONG Hua peng hao-yu LIU Zhen SHI Jiao-ying State Key Lab of CAD ＆ CG Zhejiang University Hangzhou 310027 China School of Computer and lnformation Technology Shanxi University Taiyuan 030006 China

Use of compressed mesh in parallel rendering architecture is still an unexplored area, the main challenge of which is to partition and sort the encoded mesh in compression-domain. This paper presents a mesh compression scheme PRMC (Parallel Rendering based Mesh Compression) supplying encoded meshes that can be partitioned and sorted in parallel rendering system even in encoded-domain. First, we segment the mesh into submeshes and clip the submeshes’ boundary into Runs, and then piecewise compress the submeshes and Runs respectively. With the help of several auxiliary index tables, compressed submeshes and Runs can serve as rendering primitives in parallel rendering system. Based on PRMC, we design and implement a parallel rendering architecture. Compared with uncompressed representation, experimental results showed that PRMC meshes applied in cluster parallel rendering system can dramatically reduce the communication requirement.

关键词： Cluster Parallel rendering Rendering Compression algorithm Mesh coding Mesh segmentation

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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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Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao yu-Gui peng peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

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基于PC集群并行图形绘制系统综述

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系统仿真学报 2006年第z1期18卷 70-72页

作者：刘真石教英彭浩宇秦爱红浙江大学CAD&CG国家重点实验室杭州310027

如何满足大规模数据集科学计算可视化、沉浸式虚拟现实和巨型场景绘制等应用领域都对计算机图形绘制能力的需求已经是计算机图形学领域亟需解决的问题。在高速网络互联并配有高性能3D图形卡的PC集群上构造并行图形绘制系统已经成为普遍... 详细信息

如何满足大规模数据集科学计算可视化、沉浸式虚拟现实和巨型场景绘制等应用领域都对计算机图形绘制能力的需求已经是计算机图形学领域亟需解决的问题。在高速网络互联并配有高性能3D图形卡的PC集群上构造并行图形绘制系统已经成为普遍的解决方案。根据几何图元归属判断的时机,并行图形绘制系统可分为Sort-first,Sort-middle和Sort-last。根据应用程序在集群节点间的分布,基于集群的并行图形绘制系统可分为Client-Server和Master-Slave两种系统模型。目前流行的基于PC集群并行图形绘制系统包括WireGL,Chromium,ScalableDisplayWall和AnyGL。

关键词： PC集群并行图形绘制任务划分负载平衡图像合成

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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin peng yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

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High-temperature-tolerant flexible supercapacitors: Gel polymer electrolytes and electrode materials

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Journal of Energy Chemistry 2025年第1期100卷 426-457页

作者： Chong peng Xinyi Huang Mingwei Zhao Shuling Liao Quanhong Yang Nianjun Yang Siyu yu School of Chemistry & Chemical Engineering Southwest University Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage School of Chemical Engineering and Technology and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Department of Chemistry & IMO-IMOMEC Hasselt University

The development of flexible supercapacitors(FSCs) capable of operating at high temperatures is crucial for expanding the application areas and operating conditions of supercapacitors. Gel polymer electrolytes and electrode materials stand as two key components that significantly impact the efficacy of hightemperature-tolerant FSCs(HT-FSCs). They should not only exhibit high electrochemical performance and excellent flexibility, but also withstand intense thermal stress. Considerable efforts have been devoted to enhancing their thermal stability while maintaining high electrochemical and mechanical performance. In this review, the fundamentals of HT-FSCs are outlined. A comprehensive overview of state-of-the-art progress and achievements in HT-FSCs, with a focus on thermally stable gel polymer electrolytes and electrode materials is provided. Finally, challenges and future perspectives regarding HT-FSCs are discussed, alongside strategies for elevating operational temperatures and *** review offers both theoretical foundations and practical guidelines for designing and manufacturing HT-FSCs, further promoting their widespread adoption across diverse fields.

关键词： Flexible supercapacitors High-temperature tolerance Gel polymer electrolytes Electrode materials

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