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Non-uniform Compressive Sensing Imaging Based on Image Saliency

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Chinese Journal of Electronics 2023年第1期32卷 159-165页

作者： LI Hongliang DAI feng ZHAO Qiang MA Yike CAO Juan ZHANG yongdong University of Chinese Academy of Sciences Key Lab of Intelligent Information Processing of Chinese Academy of Sciences Institute of Computing Technology Chinese Academy of Sciences University of Science and Technology of China

For more effective image sampling, compressive sensing(CS) imaging methods based on image saliency have been proposed in recent years. Those methods assign higher measurement rates to salient regions,but lower measurement rate to non-salient regions to improve the performance of CS imaging. However, those methods are block-based, which are difficult to apply to actual CS sampling, as each photodiode should strictly correspond to a block of the scene. In our work, we propose a non-uniform CS imaging method based on image saliency, which assigns higher measurement density to salient regions and lower density to non-salient regions,where measurement density is the number of pixels measured in a unit size. As the dimension of the signal is reduced, the quality of reconstructed image will be improved theoretically, which is confirmed by our experiments. Since the scene is sampled as a whole, our method can be easily applied to actual CS sampling. To verify the feasibility of our approach, we design and implement a hardware sampling system, which can apply our non-uniform sampling method to obtain measurements and reconstruct the images. To our best knowledge, this is the first CS hardware sampling system based on image saliency.

关键词： Measurement units Density measurement Imaging Image sampling Size measurement Hardware Sensors

基于视觉系统技术的无人机自主定点降落与实例验证

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粘接 2024年第9期51卷 181-184页

作者：戴永东杨金明毛峰刘玺仲坚国网江苏省电力有限公司泰州供电分公司江苏泰州225300 江苏祥泰电力实业有限公司江苏泰州225316

为解决无人机定点降落效果不好问题。提出视觉特征融合下的电力巡检无人机单兵自主精准定点降落算法。依据无人机与地标点的空间位置关系,对着陆区域位置进行估计,并通过计算数字图像的空间矩,对降落区域轮廓进行多级筛选,以检测着陆区... 详细信息

为解决无人机定点降落效果不好问题。提出视觉特征融合下的电力巡检无人机单兵自主精准定点降落算法。依据无人机与地标点的空间位置关系,对着陆区域位置进行估计,并通过计算数字图像的空间矩,对降落区域轮廓进行多级筛选,以检测着陆区域轮廓,并利用线性方程求取无人机与降落区域距离的残余误差,以此为依据,采用视觉特征融合算法获取无人机降落过程中的估计量,进而计算得出无人机单兵相对于降落标志的最优偏差角度,由此实现电力巡检无人机单兵自主精准定点降落。应用结果表明,所提方法对于地面降落区域的降落点识别效果较好,定点降落性能更佳。

关键词：视觉特征融合电力巡检无人机单兵自主精准定点降落

水基钻井固废生物资源化土壤利用技术效果分析

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环境影响评价 2020年第4期42卷 53-57页

作者：陈立荣乔川包莉军冯永东蒋学彬沈弼龙张敏刘汉军中国石油川庆钻探工程公司安全环保质量监督检测研究院四川广汉618300 中国石油西南油气田分公司质量安全环保处四川成都610051 中国石油西南油气田公司勘探事业部四川成都610500

针对四川油气田水基钻井固废的性质和目前处置利用中存在的缺陷,利用微生物具有代谢多样性、分解污染物快、污染物降解彻底等优势特征,对四川油气田水基钻井固废进行了生物处理和土壤利用试验,并先后应用于15口井。本文重点通过污染指... 详细信息

针对四川油气田水基钻井固废的性质和目前处置利用中存在的缺陷,利用微生物具有代谢多样性、分解污染物快、污染物降解彻底等优势特征,对四川油气田水基钻井固废进行了生物处理和土壤利用试验,并先后应用于15口井。本文重点通过污染指标的追踪监测,分析了生物资源化处置土壤利用技术的应用效果。研究结果表明,生物处理技术可有效降解水基钻井固废中的有机物,是一种较有效的资源化处置土壤利用技术。

关键词：钻井固体弃物生物处理资源化

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川渝地区页岩气钻井固废分类资源化处置利用

油气田环境保护 2021年第6期31卷 1-5页

作者：陈立荣胡攀峰唐攀冯永东蒋学彬王珏沈弼龙刘汉军中国石油川庆钻探工程有限公司安全环保质量监督检测研究院四川长宁天然气开发有限责任公司中国石油西南油气田公司勘探事业部中国石油西南油气田公司重庆气矿

在简要分析川渝地区主要页岩气区域长宁、威远和涪陵页岩气钻井作业主要特点基础上,重点论述了页岩气钻井不同井段及不同钻井液体系钻井固废性质特点,针对页岩气钻井水基钻井固废和油基钻屑两大类固废的资源化处置利用情况及目前存在的... 详细信息

在简要分析川渝地区主要页岩气区域长宁、威远和涪陵页岩气钻井作业主要特点基础上,重点论述了页岩气钻井不同井段及不同钻井液体系钻井固废性质特点,针对页岩气钻井水基钻井固废和油基钻屑两大类固废的资源化处置利用情况及目前存在的主要问题进行了论述,提出了川渝地区页岩气钻井固废应分井段或分不同钻井液体系进行收集并分类采用不同技术进行资源化处置利用,以达到更经济安全环保的效果。水基钻井固废就地生物处理资源化土壤利用是最优选择,第二选择是就地作为井场公路及井场场地路基建设利用,其次是制成水泥块或免烧砖,最后是转运制砖利用;脱油后的油基钻屑较好的资源利用方式是协同水泥窑焚烧处置,其次制成水泥块或作井场路基材料利用。同时针对性地提出了页岩气钻井固废分类处理利用等方面的建议措施,对油气勘探钻井环保决策管理具有一定参考价值。

关键词：页岩气钻井水基钻井固废油基钻屑资源化处置

水基钻井固废生物处理资源化土壤利用效果分析

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油气田环境保护 2022年第5期32卷 28-32页

作者：陈立荣文炜涛唐伟冯永东蒋学彬蒋世金刘汉军陈世荣舒畅中国石油集团川庆钻探工程有限公司安全环保质量监督检测研究院中国石油集团川庆钻探工程有限公司页岩气勘探开发项目经理部中国石油西南油气田分公司勘探事业部中国石油西南油气田分公司蜀南气矿

为分析水基固废经长时间生物处理后做土壤利用的效果,对6口示范应用井的土壤样品浸出液、土壤重金属、植物中重金属和土壤养分进行监测分析。结果表明:6口井水基钻井固废经生物处理所形成的土壤中有害重金属指标均不超过GB 15618-2018(... 详细信息

为分析水基固废经长时间生物处理后做土壤利用的效果,对6口示范应用井的土壤样品浸出液、土壤重金属、植物中重金属和土壤养分进行监测分析。结果表明:6口井水基钻井固废经生物处理所形成的土壤中有害重金属指标均不超过GB 15618-2018(其他,pH>7.5,风险筛选值)和HJ/T 332-2006限值要求。土壤浸出液中的无机及重金属离子等指标均低于GB 5084-2005(旱作)要求,除铁和个别点的总氮和总磷超标外,其他指标均不超过GB 3838-2002的Ⅴ类标准。土壤栽种植物中重金属含量较土壤中无明显增加,无重金属生物富集发生,除汞元素有轻微超标外,其他指标都符合GB 2762-2012中蔬菜及制品标准。土壤的养分相对较差,可以补充土壤营养物质以满足特定植物栽种的需求。水基钻井固废通过微生物处理资源化土壤利用不会对周边环境产生不利影响,是一种可行的资源化处置利用途径。

关键词：钻井固废生物处理资源化土壤化利用

维普期刊数据库博看期刊

The dynamics variation of soil moisture of shelterbelts along the Tarim Desert Highway

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Chinese Science Bulletin 2008年第S2期53卷 102-108页

作者： WANG yongdong XU XinWen LEI JiaQiang LI ShengYu ZHOU ZhiBin CHANG Qing WANG LuHai GU feng QIU YongZhi XU Bo Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Graduate University of Chinese Academy of Sciences Beijing 100049China Tarim Branch PetroChina Company LimitedKorla 841000China

We studied the variation of soil moisture as well as its regularity over the irrigation cycle at shelterbelts along the Tarim Desert Highway at different site types and different planting years. The results show that: (1) There is an obvious temporal variation of soil moisture within a typical irrigation period in shelterbelts along the Tarim Desert Highway, and the soil water storage varied linearly with the number of days after irrigation. Along the direction perpendicular to the soil top, the soil profile can be divided into four layers and each shows different dynamics of soil moisture variation, including the quickly changing layer (0—20 cm), the active layer (20—60 cm), the weakly layer (60—100 cm), and the regulated layer (under 100 cm). (2) Both the soil moisture and soil water content decreased gradually with the number of planting year, while the soil water deficit increased. It indicates that shelterbelts along the Tarim Desert Highway can retain the water accumulated from previous years. (3) The soil water storage of harden sand is the maximum among all types of sites. Specifically, it is about 1.58 times higher than that of longitudinal dune, 1.15 times higher than clay, and 1.43 times higher than flat sand. Its soil water deficit was over 900 mm.

关键词： shelterbelts along the Tarim Desert Highway dynamics of soil moisture soil water storage soil water deficit

Rumor detection with self-supervised learning on texts and social graph

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Frontiers of Computer Science 2023年第4期17卷 155-169页

作者： Yuan GAO Xiang WANG Xiangnan HE Huamin feng yongdong ZHANG School of Information Science and Technology University of Science and Technology of ChinaHefei 230026China Beijing Electronic Science and Technology Institute Beijing 102627China

Rumor detection has become an emerging and active research field in recent *** the core is to model the rumor characteristics inherent in rich information,such as propagation patterns in social network and semantic patterns in post content,and differentiate them from the ***,existing works on rumor detection fall short in modeling heterogeneous information,either using one single information source only(e.g.,social network,or post content)or ignoring the relations among multiple sources(e.g.,fusing social and content features via simple concatenation).Therefore,they possibly have drawbacks in comprehensively understanding the rumors,and detecting them *** this work,we explore contrastive self-supervised learning on heterogeneous information sources,so as to reveal their relations and characterize rumors ***,we supplement the main supervised task of detection with an auxiliary self-supervised task,which enriches post representations via post ***,given two heterogeneous views of a post(i.e.,representations encoding social patterns and semantic patterns),the discrimination is done by maximizing the mutual information between different views of the same post compared to that of other *** devise cluster-wise and instance-wise approaches to generate the views and conduct the discrimination,considering different relations of information *** term this framework as self-supervised rumor detection(SRD).Extensive experiments on three real-world datasets validate the effectiveness of SRD for automatic rumor detection on social media.

关键词： rumor detection graph neural networks selfsupervised learning social media

Evolutionary biogeography on Ophiocordyceps sinensis:An indicator of molecular phylogeny to geochronological and ecological exchanges

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Geoscience Frontiers 2020年第3期11卷 807-820页

作者： yongdong Dai Changkui Wu feng Yuan Yuanbing Wang Luodong Huang Zihong Chen Wenbo Zeng Yao Wang Zhuliang Yang Pusheng Zeng Paul Lemetti Xuanxue Mo Hong Yu Yunnan Herbal Laboratory Institute of Herb Biotic ResourcesSchool of Life SciencesYunnan UniversityKunmingYunnan Province 650091China Yunnan Herbal Biotech Co. LtdKunmingYunnan Province 650203China Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan Province 650201China National Research Center for Geoanalysis Beijing 100037China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China

The fungus Ophiocordyceps sinensis is endemic to the vast region of the Qinghai-Tibetan plateau(QTP).The unique and complex geographical environmental conditions have led to the "sky island" distribution structure of *** to limited and unbalanced sample collections,the previous data on *** regarding its genetic diversity and spatial structure have been deemed *** this study,we analyzed the diversity and phylogeographic structures of *** using internally transcribed spacer region(ITS) and 5-locus datasets by a large-scale sampling.A total of 111 haplotypes of ITS sequences were identified from 948 samples data of the fungus ***,with representing high genetic diversity,and 8 phylogenetic clades were recognized in *** the southeastern Tibet and the northwestern Yunnan were the centers of genetic diversity and genetic differentiation of the fungus,and they were inferred as the glacial refugia in the *** distribution patterns were identified to correspond to the 8 clades,including but not limited to the coexistence of widely and specific local distributive *** also revealed that the differentiation pattern of *** did not fit for the isolation-by-distance *** differentiation into the 8 clades occurred between 1.56 Myr and6.62 *** ancestor of *** most likely originated in the late Miocene(6.62 Myr) in the northwestern Yunnan,and the Scene A-C of the Qinghai-Tibetan movements may have played an important role in the differentiation of *** during the late Miocene-Pliocene *** current results provide a much clearer and detailed understanding of the genetic diversity and geographical spatial distribution of the endemic alpine fungus *** also revealed that the geochronology resulting from paleogeology could be cross-examined with biomolecular clock at a finer scale.

关键词： Large-scale sampling Phylogeographic structure Molecular clock Correlation Qinghai-Tibetan plateau

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体素效率加权平均法求解核废物桶SGS效率

核电子学与探测技术 2024年第4期44卷 648-653页

作者：郑洪龙庹先国杨剑波李锐苟睿陈杰符永东冯昊筠李宇浩魏志恒四川轻化工大学自贡643000

采用了一种基于体素效率加权平均的核废物桶SGS效率数值计算方法,通过空间点源效率函数确定断层中体素的无衰减效率,计算体素发射的γ射线进入探测器过程中在桶内介质中的衰减长度,结合介质的线衰减系数确定体素的衰减效率,对断层中所... 详细信息

采用了一种基于体素效率加权平均的核废物桶SGS效率数值计算方法,通过空间点源效率函数确定断层中体素的无衰减效率,计算体素发射的γ射线进入探测器过程中在桶内介质中的衰减长度,结合介质的线衰减系数确定体素的衰减效率,对断层中所有体素的衰减效率进行加权平均,实现断层的衰减效率计算。结果表明:桶内^(137)Cs核素的活度重建偏差为-32.53%~19.38%,实验验证了该效率数值计算方法的有效性和准确性。

关键词：放射性废物分段 γ扫描效率计算线衰减系数