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陈丹 《赤峰学院学报(自然科学版)》2011,27(3):44-46
在多尺度分解的框架下,对像素级的多源图像融合,提出一种基于低通滤波与小波变换的图像融合算法.先将低空间分辨率的多光谱图像插值,使之具有与高空间分辨率全色图像相同的分辨率,然后再对多光谱图像低频分量和全色图像低频分量进行融合处理,得到一幅具有高空间分辨率的多光谱图像.将全色图像的低频分量和多光谱图像的低频分量进行融合,以达到增强光谱图像的低频分量空间特性效果. 相似文献
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全色锐化是一种常见的图像融合技术,旨在融合卫星提供的高空间分辨率的全色图像和低空间分辨率的多光谱图像,得到高空间分辨率的多光谱图像。结合模型优化与深度学习方法的优势,提出一种模型引导的全色锐化神经网络(MoGN)。基于观测模型和融合图像的深度先验构建了一个全色锐化函数,对目标函数进行求解并将其迭代解展开为深度网络,其中空间退化和光谱退化过程通过设计专用的子网络进行近似,深度先验则由基于Unet架构的去噪器进行近似。降分辨率和全分辨率下的实验结果都证明了所提出方法的有效性。 相似文献
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高光谱遥感使宽波段遥感中不可探测的物质可以被探测,成为了遥感界的一场新的革命．由于高光谱遥感图像波段多、光谱分辨率高、数据量庞大,给高光谱遥感数据实际应用分析带来极大不便．以特征选择为目的,以协方差矩阵特征值法为评价算法,设计实现了基于遗传算法和差分演化算法的降维过程．通过与传统的序列向前搜索的特征选择进行对比实验,比照搜索结果和算法耗时,验证了演化算法在特征选择的实现过程中具有良好的性能,证明了演化算法在高光谱图像降维中的实用价值．其中差分演化算法搜索结果十分稳定,可以替代完全搜索来寻找最优解． 相似文献
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为了将低分辨率多光谱图像和高分辨率全色图像有效地融合,提出了主成分分析(PCA)变换和提升小波相结合的融合方法。小波提升后选用不同的融合规则对高低频成分进行融合,并与PCA+DWT和HSV+LWT融合法进行了比较,实验结果表明,该方法较好地保留了多光谱图像的光谱特性,提高了空间分辨率。 相似文献
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高光谱图像是一种具有高光谱分辨率的遥感图像,相比于多光谱图像,具有较多的波段数.这些波段之间存在较强的相关性,因而波段间也存在着冗余性.如何合理减少高光谱图像波段间的相关性,有效去除冗余,就成为高光谱图像处理研究的一个关键问题.基于此,对高光谱图像的相关特性进行了分析和研究. 相似文献
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扫描近场光学显微镜是20世纪80年代后期发展起来的一种分辨率超过衍射极限的新型光学显微技术。把扫描近场光学显微镜与光谱仪耦合，可进行纳米尺度的空间超高分辨率光学成象、近场局域光谱等领域中的研究。 相似文献
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《赤峰学院学报(自然科学版)》2017,(4)
河南是中国的农业大省,冬小麦是河南省最主要的粮食产物,因此大面积快速准确冬小麦种植面积信息对于粮食估产具有重大意义.本文采用冬小麦关键生育期MODIS-NDVI数据,结合不同物候期冬小麦的生物学特性、光谱特征,构建NDVI时间序列光谱,建立提取冬小麦面积的函数关系模型,确定提取冬小麦的关键时期NDVI阈值,采用决策树的方法获取了2014年河南省的冬小麦种植区域.并与2014年河南省冬小麦统计数据相比较,误差控制在3%以内.基于提取的河南省冬小麦面积的空间分布信息,结合坡度数据和各市数据,分析了不同坡度级和各县市的冬小麦种植面积比例图.为监测冬小麦面积的时空分布提供了参考.~([1]) 相似文献
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高光谱图像具有光谱分辨率高的特点,包含了大量可区分不同地物的光谱信息,在异常目标探测领域具有独特的优势.高光谱的光谱维度较高,容易导致信息冗余,使高光谱图像异常目标与背景不容易被区分出来.为了解决这个问题,提出了一种改进的基于密度峰值背景纯化的高光谱图像异常目标检测算法.通过一个极限学习网络,获得一个低维的特征空间;计算双窗内像元的局部密度,滤除背景中的异常目标获得纯背景集;用协同表示算法进行异常检测,避免对背景进行假设及估计.实验表明该方法AUC值更高,能更好地实现异常目标和背景的分离,有效地对高光谱图像进行异常目标检测,同时部分数据集的检测时间也得到了一定程度的缩短. 相似文献
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给出了基于压缩感知的全色和多光谱图像融合方法.分块压缩感知实现速度快、存储需求小,为海量遥感数据的压缩测量提供了有效策略.同时,利用小波变换的多分辨率特性,实现了压缩采样的多尺度融合.最后采用全变分技术重构融合图像.实验结果表明,与传统小波融合方法相比较,所提方法融合结果具有更高的空间分辨率和更好的光谱相关性. 相似文献
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枫香天然林生产力研究 总被引：2，自引：0，他引：2
枫香天然林分的调查结果表明,枫香是一个强阳性树种,在天然林中一般处于树冠上层,适应性较强,易于在林地受到强干扰时成为更新优势种。枫香的直径结构规律呈不规则的山状曲线,直径在24-35年期间仍然处于生长高峰期,林分总蓄积及年平均生长量大,在生产中应以培养大径材作为枫香的培养目标。 相似文献
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由于对林权客体的范围认识不同,导致学术界对林权的概念界定观点众多。林权是指以林地、林木和森林等不动产为客体而形成的一系列权利的集合体,其中林地所有权在林权体系结构中处于核心地位。在权利人行使林权的过程中,体现出权利具有支配性、对世性和排他性的特性,因此林权属于物权。 相似文献
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Erik Mygind 《Journal of Adventure Education & Outdoor Learning》2013,13(2):161-176
Physical activity levels were measured with an accelerometer in a case study including 19 children, from nine to ten years of age, in a Danish primary school. The teachers conducted their teaching in a forest every Thursday from 2000 to 2003. The purpose of this study was to measure the students' activity levels during outdoor learning days in the forest and compare them with a traditional school day on the one hand, and a traditional school day including two physical education lessons, on the other. The mean activity levels were more than twice as high on the forest days measured on two occasions. Expressed in percentages, winter (2000) measurements were 106% (range 14–194%), and summer (2001) measurements were 113% (range 41–224%) higher compared to traditional school days. Furthermore, in 2002 the mean activity level measured on a day including two physical education lessons was equal to a day in an outdoor environment. In conclusion, this case study demonstrates a significantly higher level of physical activity when indoor and outdoor learning contexts are combined. From a physical health perspective outdoor learning is recommended in the folkeskole. 相似文献
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《Journal of Adventure Education & Outdoor Learning》2007,7(2):161-176
Physical activity levels were measured with an accelerometer in a case study including 19 children, from nine to ten years of age, in a Danish primary school. The teachers conducted their teaching in a forest every Thursday from 2000 to 2003. The purpose of this study was to measure the students' activity levels during outdoor learning days in the forest and compare them with a traditional school day on the one hand, and a traditional school day including two physical education lessons, on the other. The mean activity levels were more than twice as high on the forest days measured on two occasions. Expressed in percentages, winter (2000) measurements were 106% (range 14-194%), and summer (2001) measurements were 113% (range 41-224%) higher compared to traditional school days. Furthermore, in 2002 the mean activity level measured on a day including two physical education lessons was equal to a day in an outdoor environment. In conclusion, this case study demonstrates a significantly higher level of physical activity when indoor and outdoor learning contexts are combined. From a physical health perspective outdoor learning is recommended in the folkeskole. 相似文献
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森林文化作为文化的重要组成部分,理应在文化事业发展中发挥基础性作用。文章从打造广州世界文化名城的高度出发,通过阐述森林文化所包含的内容,分析广州森林文化建设中存在的问题与不足,进而提出重点建设森林文化发展的物质载体、进行森林文化包装、创造森林文化产品等思路。同时提出了发展广州森林文化的保障机制：进一步提高全民参与水平;积极开展森林文化交流活动;加强森林文化人才队伍建设;加快林场管理体制改革;打造广州森林文化体系建设工程。 相似文献
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Erik Mygind 《Journal of Adventure Education & Outdoor Learning》2013,13(2):151-169
Two teachers from a school in Copenhagen were allowed to move their third grade teaching into a forest every Thursday for three years. Thus 20% of the class's regular teaching took place in an outdoor environment. The purpose of the present study was to ask the children how they experienced lessons in the classroom and the forest settings. Therefore, two almost identical questionnaires including a total of 26 statements adjusted to each context were completed by the children four times from 2000 to 2003. Further, in the forest questionnaire three specific statements were added about the outdoor environment plus one question about their choice of playmates during breaks at school and breaks in the forest. Ten statements were categorized as ‘social relations’, 14 statements as ‘teaching’ and finally two related to ‘self-perceived physical activity’. A significant difference (p < 0.001) was found between the school/classroom and the outdoor environment when scores from all four questionnaires (2000–2003) were summed. The categories ‘social relations’ (p < 0.001), ‘teaching’ (p < 0.001) and ‘self-perceived physical activity’ (p < 0.001) all showed significant differences. It is concluded from the present case study that the combination of classroom and outdoor teaching, over a three-year period had a positive effect on the children's social relations, experience with teaching and self-perceived physical activity level. 相似文献
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Ellen Almers Per Askerlund Sofia Kjellström 《The Journal of environmental education》2018,49(3):242-259
Utilizing forest gardens as urban settings for outdoor environmental education in Sweden is a new practice. These forest gardens combine qualities of a forest, e.g., multi-layered polyculture vegetation, with those of a school garden, such as accessibility and food production. The study explores both the perceived qualities of forest gardens in comparison to other outdoor settings and forest garden educators' ideas, purposes, and experiences of activities in a three-year forest gardening project with primary school children. The data were collected through interviews and observations and analyzed qualitatively. Four reported ideas were to give children opportunities to: feel a sense of belonging to a whole; experience self-regulation and systemic dependence; experience that they can co-create with non-human organisms; and imagine possible transformation of places. Four pedagogical forest garden features are discussed. 相似文献
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Katri Hamunen Marie Appelstrand Teppo Hujala Mikko Kurttila Nadarajah Sriskandarajah Lelde Vilkriste 《The Journal of Agricultural Education and Extension》2015,21(4):293-307
Purpose: This paper explores the concept of peer-to-peer learning (P2PL) in the context of North-European small-scale forest owners. The aim is to develop a framework for initiating new and evaluating already existing forest owners' P2PL communities.
Design: Previous studies of peer-learning are used to determine and justify eight dimensions for forest owners' P2PL. To demonstrate and test the operability of the dimensions, two potential forest owners' peer-learning cases are described. The Finnish case focuses on forest owner clubs based on group interview data and the coordinator's interview, and in the Swedish case an ongoing study circle was observed and its participants interviewed.
Findings: The eight P2PL dimensions defined are: initiation, reinforcement, content profile, participant profile, schedule, role of professionals, responsibility and role continuity. Of the described cases, Finnish forest owner clubs rely heavily on the expertise of the invited forest professionals, while owners themselves have a stronger role in Swedish study circles.
Practical Implications: The two studied cases and the fictional example demonstrate how the framework defined can be used when assessing real life cases. The framework allows describing consistently P2PL, when designing new practices or implementing step-by-step changes to modify existing P2PL practices.
Value: The framework gives new insights into the research of forest owner extension, which has had an increasing interest towards P2PL approach, but where its conceptualisation has remained vague. However, since the domain of the study is novel, further research with various case examples is needed to develop both the theoretical framework and real life practices. 相似文献