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利益相关者视角下农地整治项目绩效测度目标分析 被引量:8
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作者 郑华伟 周家俊 刘友兆 《江苏农业科学》 北大核心 2016年第5期577-580,共4页
测度目标是农地整治项目绩效测度体系运行的指南针,是开展农地整治项目绩效测度的重要基础。从农地整治项目利益相关者入手剖析农地整治项目绩效测度主体,探讨测度主体的价值观、测度主体对农地整治项目建设的利益诉求,根据价值观和利... 测度目标是农地整治项目绩效测度体系运行的指南针,是开展农地整治项目绩效测度的重要基础。从农地整治项目利益相关者入手剖析农地整治项目绩效测度主体,探讨测度主体的价值观、测度主体对农地整治项目建设的利益诉求,根据价值观和利益诉求诊断农地整治项目绩效的测度目标,提供农村公共产品和农村公共服务,满足社会公共需求,维护社会公平公正,改善社会经济发展环境,提高农民生活水平。在农地整治项目绩效测度中需要以社会公众满意为准则,有效协调政府、项目区社会公众、周围社区对农地整治项目的建设要求,确定合理的农地整治项目绩效测度目标。 展开更多
关键词 农地整治 项目绩效 利益相关者 测度目标 测度主体
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一种度量目标散射相似性的新参数 被引量:1
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作者 陈强 蒋咏梅 匡纲要 《信号处理》 CSCD 北大核心 2010年第3期332-336,共5页
针对目标相似性参数度量分布式目标与典型目标散射相似程度不准确的问题,本文利用规范散射Pau li基矢量和分布式目标相干矩阵,定义了一个度量目标散射相似性程度的新参数——目标散射相似性。由于该参数综合考虑了分布式目标主散射机制... 针对目标相似性参数度量分布式目标与典型目标散射相似程度不准确的问题,本文利用规范散射Pau li基矢量和分布式目标相干矩阵,定义了一个度量目标散射相似性程度的新参数——目标散射相似性。由于该参数综合考虑了分布式目标主散射机制、次要散射机制与规范散射的相似性,以及不同散射机制对应的发生概率,因而它能准确反映分布式目标与规范目标散射的平均近似程度。与相似性参数一样,新参数具有目标旋转不变性、尺度无关性等特性。作为一种实际应用,给出了分布式目标与金属球、角反射器等典型目标的散射相似性。结合旧金山地区AIRSAR极化数据,讨论了这些相似性测度在地物分类方面的应用。 展开更多
关键词 目标相似性测度 目标散射特征提取 分布式目标
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MSFNet:A Network for Lunar Impact Crater Detection Based on Enhanced Feature Fusion with Digital Elevation Model
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作者 HE Weidong LAI Jialong +3 位作者 ZHONG Zhicheng CUI Feifei XU Yi ZHANG Xiaoping 《深空探测学报(中英文)》 北大核心 2025年第2期190-204,共15页
Lunar impact crater detection is crucial for lunar surface studies and spacecraft landing missions,yet deep learning still struggles with accurately detecting small craters,especially when relying on incomplete catalo... Lunar impact crater detection is crucial for lunar surface studies and spacecraft landing missions,yet deep learning still struggles with accurately detecting small craters,especially when relying on incomplete catalogs.In this work,we integrate Digital Elevation Model(DEM)data to construct a high-quality dataset enriched with slope information,enabling a detailed analysis of crater features and effectively improving detection performance in complex terrains and low-contrast areas.Based on this foundation,we propose a novel two-stage detection network,MSFNet,which leverages multi-scale adaptive feature fusion and multisize ROI pooling to enhance the recognition of craters across various scales.Experimental results demonstrate that MSFNet achieves an F1 score of 74.8%on Test Region1 and a recall rate of 87%for craters with diameters larger than 2 km.Moreover,it shows exceptional performance in detecting sub-kilometer craters by successfully identifying a large number of high-confidence,previously unlabeled targets with a low false detection rate confirmed through manual review.This approach offers an efficient and reliable deep learning solution for lunar impact crater detection. 展开更多
关键词 object detection deep learning impact crater DEM
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进化规划在Multi-UCAV合作攻击伪装目标中的研究
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作者 董喆 李新广 《火力与指挥控制》 CSCD 北大核心 2011年第1期5-9,共5页
在多无人作战飞机攻击隐蔽伪装目标的任务调度规划中,针对静态武器分配方法的不足,提出了一种目标可侦测度相关模型(TDRM),该模型体现了UCAV对不同目标的侦测能力与无人作战机群整体射击效率之间的联系。将基于混合概率分布的进化规划(E... 在多无人作战飞机攻击隐蔽伪装目标的任务调度规划中,针对静态武器分配方法的不足,提出了一种目标可侦测度相关模型(TDRM),该模型体现了UCAV对不同目标的侦测能力与无人作战机群整体射击效率之间的联系。将基于混合概率分布的进化规划(EPBHPD)引入到对隐蔽伪装目标的攻击规划中,能在问题求解的精确性与实时性两者不断变化的战场环境中,通过调整进化规划中变异算子的参数和问题空间与可行解空间的映射关系可以获得合理的折中。仿真结果表明了目标可侦测度相关模型的有效性。 展开更多
关键词 无人作战飞机 协作攻击 目标测度 进化规划 混合概率分布
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Improved YOLOv8-Based Target Detection Algorithm for UAV Aerial Image
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作者 JIANG Mao-xiang SI Zhan-jun 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期86-96,共11页
In response to the challenge of low detection accuracy and susceptibility to missed and false detections of small targets in unmanned aerial vehicles(UAVs)aerial images,an improved UAV image target detection algorithm... In response to the challenge of low detection accuracy and susceptibility to missed and false detections of small targets in unmanned aerial vehicles(UAVs)aerial images,an improved UAV image target detection algorithm based on YOLOv8 was proposed in this study.To begin with,the CoordAtt attention mechanism was employed to enhance the feature extraction capability of the backbone network,thereby reducing interference from backgrounds.Additionally,the BiFPN feature fusion network with an added small object detection layer was used to enhance the model's ability to perceive for small objects.Furthermore,a multi-level fusion module was designed and proposed to effectively integrate shallow and deep information.The use of an enhanced MPDIoU loss function further improved detection performance.The experimental results based on the publicly available VisDrone2019 dataset showed that the improved model outperformed the YOLOv8 baseline model,mAP@0.5 improved by 20%,and the improved method improved the detection accuracy of the model for small targets. 展开更多
关键词 UAV YOLOv8 Attentional mechanisms Multi-scale detection MPDIoU
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基于一类新的胞腔排除遗传算法求解迭代函数系逆问题 被引量:3
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作者 王宏勇 梁勇 徐宗本 《高校应用数学学报(A辑)》 CSCD 北大核心 2001年第4期391-400,共10页
提出求解迭代函数系 ( IFS)逆问题的一类有效遗传算法 .该算法基于新发展的可拼接 /可分解编码 ,并结合使用胞腔排除技巧 .对于典型图像的应用表明 :该方法可有效应用于基于矩匹配表示的 IFS逆问题求解 ,从而为
关键词 迭代函数系逆问题 目标测度 矩匹配 编码 胞腔排除遗传算法 图像处理 非线性优化问题
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“生态脚印”指标及其评价 被引量:3
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作者 尚卫平 《统计研究》 CSSCI 北大核心 2004年第5期61-63,共3页
The paper introduces to “zoological footprint” measuring method and further tries to analyse and evaluate the method. The author points out that the indicators cannot be used to convert the concept of sustainable de... The paper introduces to “zoological footprint” measuring method and further tries to analyse and evaluate the method. The author points out that the indicators cannot be used to convert the concept of sustainable development into feasible management model and provides policy makers with a substantial standard to make decision and technical choice. 展开更多
关键词 生态脚印 生态经济学 可持续发展战略 生态目标测度方法 资源
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基于球面散射相似性的POLSAR图像分类方法 被引量:1
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作者 陈强 蒋咏梅 匡纲要 《信号处理》 CSCD 北大核心 2010年第5期659-664,共6页
针对基于H-Alpha平面的目标分类方法运算量偏大的问题,本文研究了基于散射相似性的极化合成孔径雷达(POLSAR)图像分类。首先在分析现有目标散射相似性度量参数的不足基础上,利用目标相干矩阵定义了目标散射相似性的新度量参数。该参数... 针对基于H-Alpha平面的目标分类方法运算量偏大的问题,本文研究了基于散射相似性的极化合成孔径雷达(POLSAR)图像分类。首先在分析现有目标散射相似性度量参数的不足基础上,利用目标相干矩阵定义了目标散射相似性的新度量参数。该参数综合考虑了目标主散射机制、次要散射机制与规范目标的相似性,以及不同散射机制对应的发生概率,因而它能准确反映目标与规范目标的散射相似程度。接着,考虑到表面散射在自然界中是一种普遍的散射类型,利用新参数提取了表面散射相似性参数,并从理论上分析了该参数表征目标散射类型的可行性及它与平均Alpha角、极化散射熵的约束关系。最后,利用San Francisco地区AIRSAR极化数据验证了表面散射相似性替代平均Alpha角的有效性,并讨论了表面散射相似性参数分别与现有极化散射熵替代参数的组合分类效果。实验结果表明,基于简单线性近似参数+表面散射相似性的H-Alpha替代方法更具实用性。 展开更多
关键词 目标相似性测度 目标散射特征提取 分布式目标
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矿产资源规划环境影响综合评价研究 被引量:11
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作者 李东亚 王青 +1 位作者 李富程 彭兴芝 《中国矿业》 北大核心 2009年第4期43-47,共5页
针对矿产资源开发导致的主要环境问题及其环境效应,设计出矿产资源规划环境影响评价指标体系的基本框架与内容,探讨了熵技术支持下的评价指标体系权系数的层次分析法和专家群民主决策支持下定性和定量转化的赋权值方法。以四川省第二轮... 针对矿产资源开发导致的主要环境问题及其环境效应,设计出矿产资源规划环境影响评价指标体系的基本框架与内容,探讨了熵技术支持下的评价指标体系权系数的层次分析法和专家群民主决策支持下定性和定量转化的赋权值方法。以四川省第二轮矿产资源规划环境影响评价为例,利用多层次多目标模糊综合测度模型,对矿产资源规划环境影响进行综合评价。评价结果显示,该模型具有较好的可操作性。 展开更多
关键词 矿产资源规划 环境影响评价 指标体系 权重 目标综合测度模型
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Passive target tracking with intermittent measurement based on random finite set 被引量:4
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作者 罗小波 范红旗 +1 位作者 宋志勇 付强 《Journal of Central South University》 SCIE EI CAS 2014年第6期2282-2291,共10页
In the tracking problem for the maritime radiation source by a passive sensor,there are three main difficulties,i.e.,the poor observability of the radiation source,the detection uncertainty(false and missed detections... In the tracking problem for the maritime radiation source by a passive sensor,there are three main difficulties,i.e.,the poor observability of the radiation source,the detection uncertainty(false and missed detections)and the uncertainty of the target appearing/disappearing in the field of view.These difficulties can make the establishment or maintenance of the radiation source target track invalid.By incorporating the elevation information of the passive sensor into the automatic bearings-only tracking(BOT)and consolidating these uncertainties under the framework of random finite set(RFS),a novel approach for tracking maritime radiation source target with intermittent measurement was proposed.Under the RFS framework,the target state was represented as a set that can take on either an empty set or a singleton; meanwhile,the measurement uncertainty was modeled as a Bernoulli random finite set.Moreover,the elevation information of the sensor platform was introduced to ensure observability of passive measurements and obtain the unique target localization.Simulation experiments verify the validity of the proposed approach for tracking maritime radiation source and demonstrate the superiority of the proposed approach in comparison with the traditional integrated probabilistic data association(IPDA)method.The tracking performance under different conditions,particularly involving different existence probabilities and different appearance durations of the target,indicates that the method to solve our problem is robust and effective. 展开更多
关键词 passive target tracking maritime target joint detection and tracking intermittent measurement random finite set poor observability
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An algorithm for moving target detection in IR image based on grayscale distribution and kernel function 被引量:6
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作者 王鲁平 张路平 +1 位作者 赵明 李飚 《Journal of Central South University》 SCIE EI CAS 2014年第11期4270-4278,共9页
A fast algorithm based on the grayscale distribution of infrared target and the weighted kernel function was proposed for the moving target detection(MTD) in dynamic scene of image series. This algorithm is used to de... A fast algorithm based on the grayscale distribution of infrared target and the weighted kernel function was proposed for the moving target detection(MTD) in dynamic scene of image series. This algorithm is used to deal with issues like the large computational complexity, the fluctuation of grayscale, and the noise in infrared images. Four characteristic points were selected by analyzing the grayscale distribution in infrared image, of which the series was quickly matched with an affine transformation model. The image was then divided into 32×32 squares and the gray-weighted kernel(GWK) for each square was calculated. At last, the MTD was carried out according to the variation of the four GWKs. The results indicate that the MTD can be achieved in real time using the algorithm with the fluctuations of grayscale and noise can be effectively suppressed. The detection probability is greater than 90% with the false alarm rate lower than 5% when the calculation time is less than 40 ms. 展开更多
关键词 moving target detection gray-weighted kernel function dynamic background
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