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151.
结合笔者在中南大学为期9年的遥感原理与方法课程教学实践,分析了中南大学测绘工程专业学生在该课程教学方面的学习态度和课程认识方面的现状,提出在教学过程初期加强学生对遥感历史文化及名人传记的学习,在课程教学期间自己查询专业应用前景及专业最新动态新闻,在上课期间主动向老师提问3种方法,以考核方式计入学生平时成绩,以期增强学生对该课程的学习兴趣和主动学习能力及独立思考能力,为后续遥感专业相关课程的学习奠定一定的基础。在近几年的教学实践过程中,发现该方法有效地提高了学生对该专业课的学习兴趣,学习效果超越往届学生,实践结果充分证明了该方法的有效性。  相似文献   
152.
从挖掘和利用经验数据的角度出发,提出了基于案例推理的智能化制图综合方法。首先探讨了基于算法和模型的自动综合实现方式所面临的瓶颈,并提出了采用制图综合案例推理辅助制图综合的思想;然后设计了制图综合专家案例的三元表示方法,以及获取、使用和管理流程;最后对实现该基于案例推理的智能化制图综合方法的五个关键性步骤进行了分析,并深入阐述该方法的原理和可行性,提出了基于案例推理的智能综合辅助系统架构。  相似文献   
153.
Selective omission is necessary for road network generalisation. This study investigates the use of supervised learning approaches for selective omission in a road network. To be specific, at first, the properties to measure the importance of a road in the network are viewed as input attributes, and the decision of such a road is retained or not at a specific scale is viewed as an output class; then, a number of samples with known input and output are used to train a classifier; finally, this classifier can be used to determine whether other roads to be retained or not. In this study, a total of nine supervised learning approaches, i.e., ID3, C4·5, CRT, Random Tree, support vector machine (SVM), naive Bayes (NB), K-nearest neighbour (KNN), multilayer perception (MP) and binary logistic regression (BLR), are applied to three road networks for selective omission. The performances of these approaches are evaluated by both quantitative assessment and visual inception. Results show that: (1) in most cases, these approaches are effective and their classification accuracy is between 70% and 90%; (2) most of these approaches have similar performances, and they do not have any statistically significant difference; (3) but sometimes, ID3 and BLR performs significantly better than NB and SVM; NB and KNN perform significantly worse than MP, SVM and BLR.  相似文献   
154.
高分辨率遥感影像的深度学习变化检测方法   总被引:2,自引:0,他引:2  
张鑫龙  陈秀万  李飞  杨婷 《测绘学报》2017,46(8):999-1008
为提升高分辨率遥感影像的变化检测精度,提出一种利用深度学习的变化检测方法。在预处理的基础上,利用顾及邻域信息的改进变化矢量分析算法和灰度共生矩阵算法获取影像间光谱和纹理变化,并通过设置自适应采样区间提取最可能的变化和未变化区域样本。构建并训练包含标签层的高斯伯努利深度限制玻尔兹曼机模型,以提取变化和未变化区域深层特征,从而有效辨别变化区域。通过WorldView-3与Pléiades-1影像的试验表明本文方法在变化检测精度方面优于对比方法。  相似文献   
155.
面向高光谱图像分类的半监督空谱判别分析   总被引:2,自引:2,他引:0  
侯榜焕  王锟  姚敏立  贾维敏  王榕 《测绘学报》2017,46(9):1098-1106
为充分利用高光谱图像蕴藏的空间信息提升分类精度,提出了面向高光谱图像分类的半监督空谱判别分析(S3 DA)算法。考虑高光谱图像数据集的空间一致性,首先利用少量标记样本定义类内散度矩阵,保存数据集同类像元的光谱近邻结构;再利用无标记样本定义空间近邻像元散度矩阵,揭示像元间的空间近邻结构和地物的空间分布结构信息。S3 DA既保持数据集在光谱域的可分性,又保存了无标记样本蕴藏的空间域近邻结构,增强了同类像元和空间近邻像元在投影子空间的聚集性,从而提升分类性能。在PaviaU和Indian Pines数据集的试验表明,总体分类精度分别达到81.50%和71.77%。与传统的光谱方法比较,该算法能有效提升高光谱图像数据集的地物分类精度。  相似文献   
156.
"GIS程序设计"作为地理信息科学专业的必修课,对学生专业能力的培养起到重要作用,同时GIS开发也是目前地理信息科学专业就业的主要方向。文中结合工程实践,通过校园地理信息系统、森林火灾扩散模拟分析与决策系统、小组答辩自选专题地理信息系统3个从简单到复杂的GIS项目,运用递进式的项目教学方法和团队协作、课上实践、课上提问、课内外答疑、课后作业、编写项目文档等措施对该课程进行改革探索和实践,并取得较好的教学效果。  相似文献   
157.
Significant changes in textbook publishing are at college instructors' door. Textbook representatives are directed to mesmerize potential clients with eye-catching displays and statements about digital literacy of the next generation of college students. Based on a one-year pilot study, in 2014–2015, of an electronic textbook, this commentary shares real experiences with the digital tools, contextualizes the shift in textbook publishing and research on student outcomes, and provides insight in navigating through the Brave New World of digital texts and adaptive learning tools.  相似文献   
158.
ABSTRACT

The poor performance of Pacific students at university is a concern for every level of society. Conventional models of teaching, learning and assessment have overlooked the cultural background of students, yet the effects of this oversight have been disastrous, alienating and disempowering. Studies of and developments in education in the Pacific and elsewhere offer opportunities to rethink the methods of teaching, learning and assessment of Pacific students in ways that are congruent with their home culture. Informed by the principle of so’a lau pule (the Samoan concept of consensus through consultation and conversation) and ethnographic research methods, this study describes an attempt to rethink ways of teaching, learning and assessing student performance in a third-year course on Resource Conservation and Management in the School of Geography, Earth Science and Environment at the University of the South Pacific. Introduced in 2007, the Student Innovative Contribution to Knowledge (SICK) allows students to participate in key decisions concerning teaching, learning and assessment. SICK is grounded in the principles of inclusiveness and participation. It takes account of the skills and abilities of Pacific students and is aligned with the philosophical basis of Pacific cultures. One hundred and fifty-eight students took part in this study over a 5-year period. Analysis was based on students’ written reviews of the semester’s work, in-depth conversation with individual students and the end-of-the-course evaluation. The findings show that, while students embrace the need for non-conventional forms of teaching, learning and assessment, the most frequently cited responses for non-participation are poor time management and varying perceptions of what is considered an innovative assessment. This study shows that understanding the cultural background of students is critical to creating culturally inclusive learning environments.  相似文献   
159.
Community engagement curricula and course design can provide substantial experiences for both community members and participating students. Using a case study approach, this research focuses on four steps in this process: initial community relationship forming, engaging in community service, transitioning to civic engagement, and developing a community-based research program. Narrative examples from student course evaluations position these community-based experiences as transformative for multiple parties. Institutional structures are presented as helpful entrees to engagement for students, while noting that community relationships provide contextualized, powerful, and meaningful relationships, supporting recommendations for emerging and existing community engagement programs.  相似文献   
160.
Geographers have increasingly adopted community-based learning and research into their teaching and scholarly activities since Bunge and Harvey called for an applied public geography that is both useful and challenges societal inequalities. With few exceptions, however, there has been little discussion of methods for measuring this work. Many published assessments focus on the impacts of projects on students but overlook the impacts on community partners. Impacts on faculty and the larger university community are also often ignored. This article discusses literature on the evaluation of community–university research and service learning from a critical perspective. A discussion of service learning and community-based research (CBR) projects at two Chicago universities, DePaul and Chicago State, is presented. In both cases challenges were encountered to achieve full evaluation of projects, yet both included an evaluation of university and community partners that allowed for assessment of the projects’ value to all partners.  相似文献   
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