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Log-scaling magnitude modulated watermarking scheme

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Science in China(Series F) 2007年第3期50卷 470-490页

作者： LING HeFei YUAN WuGang ZOU fuhao lu ZhengDing School of Computer Science and Technology Huazhong University of Science and Technology Wuhan430074 China

A real-time watermarking scheme with high robustness and security has been proposed based on modulating the log-scaling magnitudes of DCT coefficients, which is most suitable for JPEG images and MPEG streams. The watermark bit is encoded as the sign of the difference between the individual log-scaling magnitude of a group-region and the average one of all group-regions. The log-scaling magnitude can be modulated by modifying the low and middle frequency DCT coefficients imperceptibly. The robustness of scheme is not only dependent on those largest coefficients, but also on the other coefficients with the same proportion. It can embed 512 bits into an image with a size of 512×512, which can satisfy the payload requirement of most video watermarking applications. Moreover, the watermark embedding process only requires one-sixth of the time consumed during normal playing of video, and the watermark detection only requires one-twelfth of that, which can meet the real-time requirements of most video watermarking ap- plications. Furthermore, the experimental results show that the presented scheme is transparent and robust to significant valumetric distortions （including additive noise, low-pass filtering, Iossy compression and valumetric scaling） and a part of geometric distortions. It performs much better than the EMW algorithm in resisting all kinds of distortions except Gaussian noise with a larger deviation.

关键词： watermarking magnitude modulated watermarking log-scaling Watson perceptual model

Simulation and forecasting of fishery weather based on statistical machine learning

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Information Processing in Agriculture 2024年第1期11卷 127-142页

作者： Xueqian Fu Chunyu Zhang fuhao Chang Lingling Han Xiaolong Zhao Zhengjie Wang Qiaoyu Ma National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina College of Information and Electrical Engineering China Agricultural UniversityBeijingChina

As the new generation of artificial intelligence(AI)continues to evolve,weather big data and statistical machine learning(SML)technologies complement each other and are deeply integrated to significantly improve the processing and forecasting accuracy of fishery weather.Accurate fishery weather services play a crucial role in fishery production,serving as a great safeguard for economic benefits and personal safety,enabling fishermen to carry out fishery production better,and contributing to the sustainable development of the fishery industry.The objective of this paper is to offer an understanding of the present state of research and development in SML technology for simulating and forecasting fishery weather.Specifically,we analyze the current state of research and technical features of SML in weather and summarize the applications of SML in simulation and forecasting of fishery weather,which mainly include three aspects:fishery weather scenario generation,fishery weather forecasting,and fishery extreme weather warning.We also illustrate the main technical means and principles of SML technology.Finally,we summarize the most advanced SML fields and provide an outlook on their application value in the field of fishery weather.

关键词： Fishery weather Statistical machine learning Weather generation Weather forecasting Extreme weather warning

Crop pest image recognition based on the improved ViT method Author links open overlay panel

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Information Processing in Agriculture 2024年第2期11卷 249-259页

作者： Xueqian Fu Qiaoyu Ma Feifei Yang Chunyu Zhang Xiaolong Zhao fuhao Chang Lingling Han College of Information and Electrical Engineering China Agricultural UniversityBeijingChina National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina

The crop pests and diseases in agriculture is one of the most important reason for the reduction of bulk grain and oil crops and the decline of fruit and vegetable crop quality,which threaten macroeconomic stability and sustainable development.However,the recognition method based on manual and instruments has been unable to meet the needs of scientific research and production due to its strong subjectivity and low efficiency.The recognition method based on pattern recognition and deep learning can automatically fit image features,and use features to classify and predict images.This study introduced the improved Vision Transformer(ViT)method for crop pest image recognition.Among them,the region with the most obvious features can be effectively selected by block partition.The self-attention mechanism of the transformer can better excavate the special solution that is not an obvious lesion area.In the experiment,data with 7 classes of examples are used for verification.It can be illustrated from results that this method has high accuracy and can give full play to the advantages of image processing and recognition technology,accurately judge the crop diseases and pests category,provide method reference for agricultural diseases and pests identification research,and further optimize the crop diseases and pests control work for agricultural workers in need.

关键词： Crop diseases recognition Fruit tree leaf disease Vision Transformer Deep learning Computer Vision

Analysing the genome of hexaploid wheat and its progenitors

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Analysing the genome of hexaploid wheat and its progenitors

基于二次流控制规律的非轴对称端壁造型优化设计

第十四届全国植物基因组学大会

作者： Michael Bevan fuhao lu Cristobal Uauy Sarah Ayling Matthew Clarke Paul Bailey Manuel Spannagl Matthias Pfeifer Dan Bolser Arnaud Kerhornou Paul Kersey Klaus Mayer Mario Caccamo John Innes Centre

Bread wheat is one of the most important crops in the world that together with rice and maize provide the bulk of nutrition for humans and domesticated animals.Global production was 661m tonnes in 2012,with increased consumption for food leading to a 10%reduction in global stocks.To increase wheat yields and improve yield stability

关键词： genomics wheat crop improvement polyploidy

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航空动力学报 2024年第2期39卷 193-211页

作者：尤付浩李相君鲁庆崔义强朱政宇大连海事大学船舶与海洋工程学院辽宁大连116026

针对高负荷轴流压气机端壁角区分离问题,提出了一种多局部控制端壁二次流、适用于多工况的端壁造型方法,在选取参数的同时考虑结合优化,通过少量参数来控制型面变化。该方法的思想是定义对端壁二次流有不同影响的表面单元,然后通过几何... 详细信息

针对高负荷轴流压气机端壁角区分离问题,提出了一种多局部控制端壁二次流、适用于多工况的端壁造型方法,在选取参数的同时考虑结合优化,通过少量参数来控制型面变化。该方法的思想是定义对端壁二次流有不同影响的表面单元,然后通过几何叠加的方式将它们的影响组合起来。而后将该方法应用到多目标优化设计中。优化结果表明:高负荷叶栅的总压损失系数在设计点降低0.03,大攻角点降低0.05时,与传统方法相比,新方法的优化设计过程收敛更快,计算时间更短。最优造型设计规律是在叶片通道内构造一个吸力侧上升、压力侧下沉的端壁面,同时局部抬高吸力面角区,前缘至凸起部位上坡平缓。流场分析表明,该方法在控制变量较少的情况下,对端壁几何形状产生了清晰直观的影响。同时有效结合表面单元在二次流控制中的作用,抑制角区分离。由此可见,新开发的端壁造型优化设计方法与以往的研究相比具有一定的优势。

关键词：角区分离端壁造型流动控制优化设计压气机

STATISTICAL MODEL OF QUANTIZED DCT COEFFICIENTS

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STATISTICAL MODEL OF QUANTIZED DCT COEFFICIENTS

滇西雪龙山杂岩新生代高钾花岗质岩脉锆石U-Pb年代学、Hf同位素组成与区域构造意义

第七届国际信号处理会议

作者： fuhao Zou Zhengding lu Hefei Ling (School of Computer Science&Technology Huazhong University of Science&Technology Wuhan China 430074)

In this paper we propose a two-parameter probability model of quantized DCT coefficients for image and video (i.e. JPEG&MPEG format materials), which is based on empirical observation of their stat

关键词： Digital Watermarking Generalized Laplacian Distribution Maximum likelihood Estimation

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矿物岩石 2024年第2期44卷 12-29页

作者：陈玮熊富浩赵涵蒋文忠成都理工大学地球科学学院四川成都610059 自然资源部深地科学与探测技术实验室北京100029

新生代印度-欧亚板块碰撞后,增厚的羌塘-三江特提斯区域地壳因造山后伸展作用形成一系列高钾岩浆。本次研究以雪龙山杂岩中的糜棱岩化高钾花岗质岩脉为研究对象,通过构造变形解析、锆石U-Pb与Hf同位素研究、岩石地球化学与岩石成因分析... 详细信息

新生代印度-欧亚板块碰撞后,增厚的羌塘-三江特提斯区域地壳因造山后伸展作用形成一系列高钾岩浆。本次研究以雪龙山杂岩中的糜棱岩化高钾花岗质岩脉为研究对象,通过构造变形解析、锆石U-Pb与Hf同位素研究、岩石地球化学与岩石成因分析,以期对哀牢山-红河剪切带北段新生代构造演化进行限定。结果表明,3个花岗质岩脉锆石新生代U-Pb年龄分别为34.8±0.4Ma,35.4±0.3Ma和32.6±0.2Ma,反映了岩浆就位时间;锆石εHf(t)值分别为+7.8~+8.6,+3.7~+7.0和+6.3~+9.2,二阶段模式年龄分别为563~658Ma,664~876Ma和524~706Ma,表明其源区为新生镁铁质下地壳。3个花岗质岩脉岩石地球化学特征相似,ω(SiO_(2))(70.14%~73.74%)较高ω(MgO)(0.07%~0.84%)、ω(Y)(3.92×10^(-6)~8.66×10^(-6))、ω(Yb)(0.27×10^(-6)~0.77×10^(-6))含量较低,具有高Sr/Y比值(42.54~129.18),低Na_(2)O/K_(2)O比值(0.82~1.66)特征,呈现出(类)埃达克质岩浆属性。综合分析表明,在始新世-渐新世,三江地区增厚的下地壳在后续重力失稳作用下发生碰撞后板片断离,诱发深部地幔物质上涌和底侵加厚地壳,进而促使加厚地壳熔融,形成(类)埃达克质高钾岩浆。在岩浆上涌过程中,捕获或继承了古特提斯洋演化不同阶段的锆石。结合岩石变形分析,哀牢山-红河剪切带新生代左行走滑剪切应在32.6Ma之后。

关键词：雪龙山杂岩锆石U-Pb与Hf同位素分析岩石地球化学高钾花岗岩脉哀牢山-红河剪切带

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食管癌质子和重离子治疗现状与展望

中华肿瘤防治杂志 2024年第9期31卷 575-580页

作者：王康徐福昊袁双虎山东第一医科大学(山东省医学科学院)研究生部山东济南250117 山东省肿瘤防治研究院(山东省肿瘤医院)放疗科山东第一医科大学(山东省医学科学院)山东济南250117 中国科学技术大学附属第一医院(安徽省立医院)放疗科中国科学技术大学生命科学与医学部安徽合肥230031

目的综述食管癌质子和重离子治疗的剂量学优势、临床疗效、局限性并展望其发展前景,为提高食管癌的放射治疗疗效提供参考。方法使用PubMed及中国知网数据库检索系统,以“食管癌、放射治疗、质子治疗、重离子治疗、碳离子放射治疗”等为... 详细信息

目的综述食管癌质子和重离子治疗的剂量学优势、临床疗效、局限性并展望其发展前景,为提高食管癌的放射治疗疗效提供参考。方法使用PubMed及中国知网数据库检索系统,以“食管癌、放射治疗、质子治疗、重离子治疗、碳离子放射治疗”等为中文关键词,“esophageal cancer,radiotherapy,proton therapy,carbon-ion radiotherapy”为英文关键词进行检索。纳入标准:(1)食管癌的质子治疗;(2)食管癌的重离子治疗;(3)食管癌放射和免疫联合治疗。排除标准:(1)数据陈旧文献;(2)内容相似或重复。最终共纳入38篇文献。结果食管癌质子、重离子治疗具有独特剂量学优势,尤其是对肿瘤部位的局部高剂量辐射与周围正常器官和组织的保护作用,临床疗效也优于光子治疗。然而仍具有局限性,与免疫的联合治疗需进一步临床试验证实。结论质子和重离子治疗是一种有前途的方式,但还需要大量研究结果来进行验证和补充现有的临床和临床前数据,让其发挥更大优势,给患者带来更多生存获益。

关键词：食管癌质子疗法重离子治疗放射治疗

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乙酸丁酯降解菌的分离鉴定及降解特性

微生物学通报 2024年第6期51卷 2215-2226页

作者：王雪薛福浩成卓韦浙江工业大学环境学院浙江杭州310014

【背景】酯类是工业生产废气中常见组分之一。利用微生物降解含酯类废气具有研究价值和应用前景。【目的】从浙江某污水处理厂活性污泥中驯化分离出一株能以乙酸丁酯为唯一碳源生长的降解菌,研究其降解乙酸丁酯的特性及降解途径。【方... 详细信息

【背景】酯类是工业生产废气中常见组分之一。利用微生物降解含酯类废气具有研究价值和应用前景。【目的】从浙江某污水处理厂活性污泥中驯化分离出一株能以乙酸丁酯为唯一碳源生长的降解菌,研究其降解乙酸丁酯的特性及降解途径。【方法】对分离纯化的降解菌进行形态学、生理生化及分子生物学鉴定以确定种属,采用单因素变量法分析菌株降解乙酸丁酯的特性,并对降解中间产物进行检测和分析。【结果】经生理生化和16S rRNA基因鉴定为莫德斯托斯不动杆菌(Acinetobacter modestus),命名为HYY-1。菌株HYY-1在碱性(pH 8.0-10.0)条件下对乙酸丁酯有较好的降解效果。在乙酸丁酯浓度为264.75-1 059.00 mg/L时降解率较高,在120 h内对最高浓度乙酸丁酯的降解率可达100%。菌株HYY-1的初始接种浓度对降解效率影响不大,120 h内不同接种浓度下的降解效率均能达到100%。菌株HYY-1降解乙酸丁酯的中间产物为正丁醇和乙酸,最终降解为CO2、细菌生物量等,在不同初始乙酸丁酯浓度下降解产物比例有所不同。【结论】菌株HYY-1具有高效降解乙酸丁酯的能力,推测可能的降解机制为经酯键水解酶部分转化为正丁醇和乙酸,最终完全矿化为CO2和细菌生物量。本研究为进一步解析乙酸丁酯生物降解机理和探索乙酸丁酯污染环境的生物修复路径提供了理论支持。

关键词：乙酸丁酯降解菌分离鉴定降解特性碳平衡降解途径