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声呐图像水下目标识别综述与展望

电子与信息学报 2024年第5期46卷 1742-1760页

作者：黄海宁李宝奇刘纪元刘正君韦琳哲赵爽中国科学院声学研究所北京100190 中国科学院先进水下信息技术重点实验室北京100190 中国科学院大学北京100049

随着海洋资源开发和水下作业的增加,声呐图像水下目标识别已成为热门研究领域。该文全面回顾了该领域的现状和未来趋势。首先,强调了声呐图像水下目标识别的背景和重要性,指出水下环境复杂和样本稀缺增加了任务难度。其次,深入探讨了典... 详细信息

随着海洋资源开发和水下作业的增加,声呐图像水下目标识别已成为热门研究领域。该文全面回顾了该领域的现状和未来趋势。首先,强调了声呐图像水下目标识别的背景和重要性,指出水下环境复杂和样本稀缺增加了任务难度。其次,深入探讨了典型的成像声呐技术,包括前视声呐、侧扫声呐、合成孔径声呐、多波束测深仪、干涉合成孔径声呐和前视三维声呐等。接下来,系统地审视了二维和三维声呐图像水下目标识别方法,比较了不同算法的优劣,还讨论了声呐图像序列的关联识别方法。最后,总结了当前领域的主要挑战,展望了未来研究方向,旨在促进水下声呐目标识别领域的发展。

关键词：声呐图像目标识别深度学习合成孔径声呐前视三维声呐目标识别

结合偏航校正的合成孔径声呐大测绘带运动补偿方法

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声学学报 2024年第4期49卷 709-718页

作者：陈世平任露露张鹏飞王朋迟骋刘纪元中国科学院声学研究所北京100190 中国科学院先进水下信息技术重点实验室北京100190 中国科学院大学北京100049

传统基于频域补偿相位的运动补偿方法难以校正姿态误差造成的波束照射方向偏转,因此提出了一种基于偏航校正的合成孔径声呐大测绘带运动补偿方法。首先,利用时延的距离空变特性校正时延估计野值,提高估计精度和稳健性;其次,通过在后向... 详细信息

传统基于频域补偿相位的运动补偿方法难以校正姿态误差造成的波束照射方向偏转,因此提出了一种基于偏航校正的合成孔径声呐大测绘带运动补偿方法。首先,利用时延的距离空变特性校正时延估计野值,提高估计精度和稳健性;其次,通过在后向投影算法的成像过程中对实孔径成像网格进行旋转来校正偏航造成的波束照射方向偏转;最后,通过分段二维轨迹估计和分段成像克服运动误差的距离空变特性,实现大测绘带运动补偿。仿真结果表明,所提方法能够有效抑制偏航误差导致的点目标图像主瓣展宽、旁瓣升高和模糊现象。实验结果表明,相比于参考方法,所提方法在小偏航角和大偏航角条件下均显著提高了成像质量,有效校正了偏航造成的运动误差,实现了大测绘带精确成像。

关键词：合成孔径声呐运动补偿偏航校正后向投影算法

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固态电解质离子传输机制研究进展

化学工业与工程 2024年第1期41卷 71-82页

作者：刁庆宇刘吉源王列李传崴刘兴江徐强天津大学化工学院天津300350 天津大学机械工程学院天津300350 中国电子科技集团公司第十八研究所化学与物理电源重点实验室天津300384

全固态锂金属电池具有较高的安全性和稳定性,是替代传统锂离子电池成为下一代储能装置的理想选择。然而,固态电解质相较于液体电解液而言,其较低的离子电导率仍然是阻碍全固态锂金属电池得到快速发展的一个关键。综述了不同类型固态电... 详细信息

全固态锂金属电池具有较高的安全性和稳定性,是替代传统锂离子电池成为下一代储能装置的理想选择。然而,固态电解质相较于液体电解液而言,其较低的离子电导率仍然是阻碍全固态锂金属电池得到快速发展的一个关键。综述了不同类型固态电解质离子传输机理,总结了提高固态电解质电导率的改进策略和最新研究进展,归纳了改善固态电解质离子传输性能的技术路线,并对未来新型固态电解质的设计与发展作了展望。

关键词：固态电解质离子传输改性策略研究进展

地舒单抗用药人群拔牙围手术期管理的研究进展

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中华口腔医学杂志 2024年第8期59卷 840-845页

作者：姜志深曹钰彬曹志炜叶立刘济远潘剑四川大学华西口腔医院口腔颌面外科、口腔疾病防治全国重点实验室、国家口腔医学中心、国家口腔疾病临床医学研究中心成都610041

地舒单抗是一种全人源单克隆抗体,用于预防恶性肿瘤骨相关事件和治疗骨折高风险的骨质疏松。2019年,地舒单抗于我国获批上市后,地舒单抗引发的药物相关性颌骨坏死(DRONJ)也日益受到关注。DRONJ与双膦酸盐引发的药物相关性颌骨坏死类似,... 详细信息

地舒单抗是一种全人源单克隆抗体,用于预防恶性肿瘤骨相关事件和治疗骨折高风险的骨质疏松。2019年,地舒单抗于我国获批上市后,地舒单抗引发的药物相关性颌骨坏死(DRONJ)也日益受到关注。DRONJ与双膦酸盐引发的药物相关性颌骨坏死类似,多发生于拔牙术后,表现为颌骨裸露坏死、流脓、颌面部肿胀及疼痛等,严重影响患者生活质量。但DRONJ的拔牙围手术期管理策略与双膦酸盐相关性颌骨坏死不同。本文从口腔卫生保健、抗生素药物应用、围手术期停药和手术策略选择等方面,总结DRONJ高危患者的拔牙围手术期管理策略,旨在为口腔外科医师应对使用地舒单抗患者的拔牙手术提供参考。

关键词：拔牙地舒单抗双膦酸盐颌骨坏死抗生素

Relationships between the activities and Ce^(3+)concentrations of CeO_(2)(111)for CO oxidation:A first-principle investigation

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Chinese Chemical Letters 2021年第3期32卷 1127-1130页

作者： jiyuan liu Xueqing Gong Key Laboratory for Advanced Materials Centre for Computational Chemistry and Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

CO oxidation at ceria surfaces has been studied for decades,and many efforts have been devoted to understanding the effect of surface reduction on the catalytic *** this work,we theoretically studied the CO oxidation on the clean and reduced CeO_(2)(111)surfaces using different surface cells to dete rmine the relationships between the reduction degrees and calculated reaction *** is found that the calculated barrier for the direct reaction between CO and surface lattice O drastically decreases with the increase of surface reduction *** electronic analysis,we found that the surface reduction can lead to the occurrence of localized electrons at the surface Ce,which affects the charge distribution at surface *** the result,the surface O becomes more negatively charged and therefore more active in reacting with *** work then suggests that the localized 4 f electron reservoir of Ce can act as the"pseudo-anion"at reduced CeO_(2) surfaces to activate surface lattice O for catalytic oxidative reactions.

关键词： CO oxidation CeO_(2)(111) Mars-van krevelen mechanism DFT+U Surface reduction

Spatio-temporal Characteristics of Disturbance of Land Use Change on Major Ecosystem Function Zones in China

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Chinese Geographical Science 2015年第5期25卷 523-536页

作者： NING Jia liu jiyuan ZHAO Guosong Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

In recent years, because of increasing human activities, ecosystems have been substantially disturbed and their service functions have been greatly compromised. Based on the effect of land use changes on the major ecosystem services, we estimated the ecosystem comprehensive anthropogenic disturbance index(ECADI) and analyzed the spatio-temporal characteristics of changes in the ECADI in China from 1990 to 2010. The average ECADI of the major ecosystem function zones in China in 2010 is approximately 0.382. The ECADI of Northeast China and North China is slightly higher than that of Northwest China and Southwest China. Most zones have slight changes in the ECADI. The average increases of ECADI in the major ecosystem function zones in China from 1990 to 2000 and from 2000 to 2010 are 0.0024 and 0.0002, respectively. The increase is mainly due to reclamation and urbanization, whereas the decrease is due to the implementation of ecosystem protection policies. During the last 20 years, the ECADI of water resources conservation zones increased first, and then stopped. The ECADI of soil conservation zones increased first, and then declined. The ECADI of sandstorm prevention zones, biodiversity conservation zones and flooding mitigation zones increased continuously. Our results may provide proposals to the government regarding land use planning and ecosystem protection plans in the major ecosystem zones. The major ecosystem function zones in the western part of China have been protected effectively. However, the major ecosystem function zones in the eastern part of China require more protection in the future.

关键词： land use change major ecosystems services disturbance spatiotemporal patterns China

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合成孔径声呐时延估计误差校正改进算法

声学技术 2024年第1期43卷 11-20页

作者：陈世平张鹏飞王朋迟骋刘纪元中国科学院声学研究所北京100190 中国科学院先进水下信息技术重点实验室北京100190 中国科学院大学北京100049

由相位解缠错误造成的时延估计误差会严重降低合成孔径声呐时延估计的精度。现有的时延估计误差校正算法采用二次函数作为时延的拟合模型,该模型在距离向近端和远端处不符合时延空变规律,拟合误差较大且无法估计载体的横荡和升沉运动。... 详细信息

由相位解缠错误造成的时延估计误差会严重降低合成孔径声呐时延估计的精度。现有的时延估计误差校正算法采用二次函数作为时延的拟合模型,该模型在距离向近端和远端处不符合时延空变规律,拟合误差较大且无法估计载体的横荡和升沉运动。针对该问题,文章提出一种改进的时延估计误差校正算法,利用时延的距离空变函数代替二次函数作为拟合模型。数值仿真和实验结果表明,相较于参考算法,改进算法校正时延估计误差的效果更好、速度更快,同时还能准确地估计载体的横荡和升沉运动。运动补偿结果显示了改进算法能较好地提升成像质量。

关键词：合成孔径声呐时延估计相位解缠随机抽样一致算法

Optimal decision-making model of spatial sampling for survey of China's land with remotely sensed data

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Science China Earth Sciences 2005年第6期48卷 752-764页

作者： LI Lianfa WANG Jinfeng liu jiyuan Institute of Geographic Sciences&Natural Resources Research Chinese Academy of SciencesBeijing 100101China Department of Intelligence Science Peking UniversityBeijing 100087China

In the remote sensing survey of the country land, cost and accuracy are a pair of conflicts, for which spatial sampling is a preferable solution with the aim of an optimal balance between economic input and accuracy of results, or in other words, acquirement of higher ac-curacy at less cost. Counter to drawbacks of previous application models, e.g. lack of compre-hensive and quantitative-comparison, the optimal decision-making model of spatial sampling is proposed. This model first acquires the possible accuracy-cost diagrams of multiple schemes through initial spatial exploration, then regresses them and standardizes them into a unified ref-erence frame, and finally produces the relatively optimal sampling scheme by using the discrete decision-making function (built by this paper) and comparing them in combination with the dia-grams. According to the test result in the survey of the arable land using remotely sensed data, the Sandwich model, while applied in the survey of the thin-feature and cultivated land areas with aerial photos, can better realize the goal of the best balance between investment and accuracy. With this case and other cases, it is shown that the optimal decision-making model of spatial sampling is a good choice in the survey of the farm areas using remote sensing, with its distin-guished benefit of higher precision at less cost or vice versa. In order to extensively apply the model in the surveys of natural resources, including arable farm areas, this paper proposes the prototype of development using the component technology, that could considerably improve the analysis efficiency by insetting program components within the software environment of GIS and RS.

关键词： survey of countrywide land with RS data spatial sampling optimal decision-making model of spatial sampling.

Simulation study of China's net primary production

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Chinese Science Bulletin 2008年第3期53卷 434-443页

作者： GAO ZhiQiang liu jiyuan Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Spatial and temporal distribution of vegetation net primary production(NPP)in China was studied us-ing three light-use efficiency models(CASA,GLOPEM and GEOLUE)and two mechanistic ecological process models(CEVSA,GEOPRO).Based on spatial and temporal analysis(***,seasonally and annually)of simulated results from ecological process mechanism models of CASA,GLOPEM and CEVSA,the following conclusions could be made:(1)during the last 20 years,NPP change in China followed closely the seasonal change of climate affected by monsoon with an overall trend of increas-ing;(2)simulated average seasonal NPP was:0.571±0.2 GtC in spring,1.573±0.4 GtC in summer,0.6±0.2 GtC in autumn,and 0.12±0.1 GtC in *** annual NPP in China was 2.864±1 *** the five models were able to simulate seasonal and spatial features of biomass for different ecological types in *** paper provides a baseline for China's total biomass *** also offers a means of estimating the NPP change due to afforestation,reforestation,conservation and other human activities and could aid people in using for-mentioned carbon sinks to fulfill China's commitment of reducing greenhouse gases.

关键词：中国净初级生产力模型比较时空变化