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991.
接收函数作为地震学研究中的重要方法之一,在间断面成像、S波速度结构反演方面应用广泛.然而,接收函数方法需要耗费大量的人工成本挑选可用的数据,这不利于我们快速准确地获得地下结构,因此发展快速准确的数据自动处理方法具有十分重要的意义.本文针对这一问题,提出利用深度学习方法自动挑选接收函数,并使用中国地震局的牡丹江地震台(MDJ)和北京地震台(BJT)于2000年至2019年记录的波形数据提取的接收函数进行试验.结果表明,应用深度学习方法挑选接收函数是可行的,使用自动挑选的接收函数对台站下方地壳结构进行估计,结果与使用人工挑选的接收函数估计的结果具有较高的一致性.通过使用不同样本比例的训练集和测试集进行分析,本文提出的方法具有对训练集的数据量要求较低、利用率高、适合多台数据联合训练等特点.该方法在建立台网接收函数自动挑选模型字典、区域接收函数自动挑选模型等方面具有巨大应用潜力. 相似文献
992.
993.
Behzad Jamali Ehsan Haghighat Aleksandar Ignjatovic João P. Leitão Ana Deletic 《水文研究》2021,35(4):e14064
Two-dimensional hydrodynamic models numerically solve full Shallow Water Equations (SWEs). Despite their high accuracy, these models have long simulation run times and therefore are of limited use for exploratory or real-time flood predictions. We investigated the possibility of improving flood modelling speed using Machine Learning (ML). We propose a new method that replaces the computationally expensive parts of the hydrodynamic models with simple and efficient data-driven approximations. Our hypothesis is that by integrating ML with physics-based numerical methods, we can achieve improved generalization performance: that is, the trained model for one case study can be used in other studies without the need for new training. We tested two ML approaches: for the first, we integrated curve fitting, and, for the second, artificial neural networks (ANN) with a finite volume scheme to solve the local inertial approximation of the SWEs. The data-driven models approximated the Momentum Equation, which explicitly solved the time derivative of flow rates. Water depths were then updated by applying a water balance equation. We also tested two different training datasets: the simulated dataset, generated from the results of hydrodynamic model, and the random dataset, generated by directly solving the momentum equation on randomly sampled input data. Various combinations of input features, for example, water slope and depth, were explored. The proposed models were trained in a small hypothetical case and tested in a different hypothetical and in two real case studies. Results showed that the curve-fitting method can be implemented successfully, given sufficient training and input data. The ANN model trained with a random dataset was substantially more accurate than that of the model trained with the simulated dataset. However, it was not successful in the real case studies. The curve-fitting method resulted in better generalization performance and increased the simulation speed of the local inertial model by 23%. Future research should test the performance of ML in terms of an increase in stable time step size and approximation of the full SWEs. 相似文献
994.
Günther Weiss 《The Journal of geography》2017,116(5):206-216
This article reports on the possibilities and challenges of starting problem-oriented learning in geography lessons. The article focuses on the features of motivating problems, because one of the essential functions of the problem to start with is to animate learners to solve it. The analysis of various introductions to problem-oriented learning of geographic topics in primary schools shows that generating a cognitive dissonance is highly suitable for inducing a desire to learn. As a motivating role relative to the problem, the helper and expert roles were seen as being ideal. 相似文献
995.
Kolb's Experiential Learning Theory and Its Application in Geography in Higher Education 总被引:2,自引:2,他引:0
《The Journal of geography》2012,111(5):185-195
Abstract Kolb's experiential learning theory is one of the best known educational theories in higher education. The theory presents a way of structuring a session or a whole course using a learning cycle. The different stages of the cycle are associated with distinct learning styles. Individuals differ in their preferred learning styles, and recognizing this is the first stage in raising students' awareness of the alternative approaches possible. This article presents some case studies of ways in which the theory can be applied in university geography. 相似文献
996.
《The Journal of geography》2012,111(4):146-157
Abstract Active learning strategies include a variety of methods, such as inquiry and discovery, in which students are actively engaged in the learning process. This article describes several strategies that can be used in secondary-or college-level world geography courses. The goal of these activities is to foster development of a spatial perspective in students through frequent analysis and interpretation of spatial data. Detailed examples of one particular technique, the “atlas warmup”, are included. Active approaches supplement expository teaching of standards-based geography concepts and current geographic issues. Assessment of the impact of these methods reveals the need for ongoing guided practice in the use of these skills. 相似文献
997.
《The Journal of geography》2012,111(4-5):167-174
Abstract Geography increasingly relies on training of professionals who can apply geographic concepts to solve real-world problems. The planning profession for years has been training professionals to work in the area of community planning. Planning programs typically include experiential learning modules throughout the curriculum. This article looks at how community planning approaches can be incorporated into geography programs in lower level courses to: (1) provide exposure to practical applications of geographic concepts; (2) give students experience with team dynamics; and (3) provide students with experience in real-world client relations. Advantages and challenges of experiential learning are identified and discussed. An example of an experiential learning exercise adapted from a planning application is presented. The exercise was developed to enhance learning in a geography curriculum. 相似文献
998.
《The Journal of geography》2012,111(4-5):210-218
Abstract This article presents a field technique that exposes students to the indirect effects of habitat fragmentation on plant distributions through studying edge effects. This assignment, suited for students in an introductory biogeography or resource geography class, increases students' knowledge of basic biogeographic concepts such as environmental gradients and disturbance in addition to formulating research questions and design. In this exercise, fieldwork can be implemented with simple tools that are easily obtainable and found in most physical geography labs. In this example, student response to the exercise was positive; they indicated that the exercise was a fun and interactive way to learn fundamental biogeographic concepts. 相似文献
999.
《The Journal of geography》2012,111(1):17-23
Abstract In the technological world of the Twenty-first Century, students must be information literate. They must have the skills to access, evaluate, and utilize information needed in their undergraduate experience and in their future endeavors. It is important for Geography majors to acquire these skills as part of their undergraduate education. At one institution of higher learning, information literacy learning is embedded in the Geography curriculum. An online instrument to assess information literacy skills is used to evaluate seniors. In this article, goals for information literacy, the creation of the information literacy assessment instrument and the results of assessment testing are discussed. 相似文献
1000.
《The Journal of geography》2012,111(6):217-225
Abstract This article situates geospatial technologies as a constructivist tool in the K-12 classroom and examines student experiences with real-time authentic geospatial data provided through a hybrid adventure learning environment. Qualitative data from seven student focus groups demonstrate the effectiveness of using real-time authentic data, peer collaboration, and geospatial technologies in learning geography. We conclude with recommendations about geospatial technology curricula, geospatial lesson design, providing preservice teachers with geographic technological pedagogical content knowledge, and encouraging further research to investigate the impact, affordances, and pedagogical implications of geospatial technologies and data in the K–12 classroom. 相似文献