3 research outputs found
Mapping horizontal and vertical urban densification in Denmark with Landsat time-series from 1985 to 2018: a semantic segmentation solution
Landsat imagery is an unparalleled freely available data source that allows
reconstructing horizontal and vertical urban form. This paper addresses the
challenge of using Landsat data, particularly its 30m spatial resolution, for
monitoring three-dimensional urban densification. We compare temporal and
spatial transferability of an adapted DeepLab model with a simple fully
convolutional network (FCN) and a texture-based random forest (RF) model to map
urban density in the two morphological dimensions: horizontal (compact, open,
sparse) and vertical (high rise, low rise). We test whether a model trained on
the 2014 data can be applied to 2006 and 1995 for Denmark, and examine whether
we could use the model trained on the Danish data to accurately map other
European cities. Our results show that an implementation of deep networks and
the inclusion of multi-scale contextual information greatly improve the
classification and the model's ability to generalize across space and time.
DeepLab provides more accurate horizontal and vertical classifications than FCN
when sufficient training data is available. By using DeepLab, the F1 score can
be increased by 4 and 10 percentage points for detecting vertical urban growth
compared to FCN and RF for Denmark. For mapping the other European cities with
training data from Denmark, DeepLab also shows an advantage of 6 percentage
points over RF for both the dimensions. The resulting maps across the years
1985 to 2018 reveal different patterns of urban growth between Copenhagen and
Aarhus, the two largest cities in Denmark, illustrating that those cities have
used various planning policies in addressing population growth and housing
supply challenges. In summary, we propose a transferable deep learning approach
for automated, long-term mapping of urban form from Landsat images.Comment: Accepted manuscript including appendix (supplementary file
A New Stereo Pair Disparity Index (SPDI) for Detecting Built-Up Areas from High-Resolution Stereo Imagery
Within-class spectral variation and between-class spectral confusion in remotely sensed imagery degrades the performance of built-up area detection when using planar texture, shape, and spectral features. Terrain slopes and building heights extracted from auxiliary data, such as Digital Surface Models (DSMs) however, can improve the results. Stereo imagery incorporates height information unlike single remotely sensed images. In this study, a new Stereo Pair Disparity Index (SPDI) for indicating built-up areas is calculated from stereo-extracted disparity information. Further, a new method of detecting built-up areas from stereo pairs is proposed based on the SPDI, using disparity information to establish the relationship between two images of a stereo pair. As shown in the experimental results for two stereo pairs covering different scenes with diverse urban settings, the SPDI effectively differentiates between built-up and non-built-up areas. Our proposed method achieves higher accuracy built-up area results from stereo images than the traditional method for single images, and two other widely-applied DSM-based methods for stereo images. Our approach is suitable for spaceborne and airborne stereo pairs and triplets. Our research introduces a new effective height feature (SPDI) for detecting built-up areas from stereo imagery with no need for DSMs
THE ROLE OF JAVANESE CULTURE IN CHARACTER BUILDING AT ELEMENTARY SCHOOL
Nowadays, character education becomes a major concern in Indonesia. Character development has been done
by various strategy, but the results is yet to be seen. Character development should beginin elementary school
in order that the children's charactercould formed early so that it could be developed until they are mature.
One of the efforts of character building is integrating the local wisdom in learning. One of them is the
Javanese culture. Javanese culture has a variety of rules called the "unggah-ungguh" that always give good
models to the public community, especially to the Javanese. Along with the times, the Javanese culture that
upholds ethics began to degraded and replaced by foreign cultures that came later. The parents’ roles in
instilling the Javanese culture to their children also decreased gradually. This paper will examine the Javanese
culture’s roles toward the character building in elementary schools’ students. Descriptive method supported by
a depth review of the literature and the previous studies is used in this paper as a method. Based on the results
of these reviews, we obtain some information about the types and mechanisms of Javanese culture in character
building of students, especially elementary school students