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In order to prove that the Arabian Plate is a tectonically active region even in its shield areas, we obtained the attenuation structure t p * of the upper mantle beneath the Arabian Plate by applying the spectral inversion method to the newly established seismic network in Saudi Arabia operated by the Saudi Geological Survey (SGS). The data sets consisted of good quality vertical components of the teleseismic events for more than 4400 spectral ratios. The result showed significant and diverse t p * structures between the eastern and western regions of the Arabian Plate. High t p * was the predominant feature underneath the Arabian Shield (western Arabia) and low t p * within the Arabian Platform (eastern Arabia). The obtained t P * values range from −1.0 s to 1.0 s. The observed high t p * patterns followed a line from north to south through the Arabian Shield along the Red Sea margin. The high t p * distribution closely followed the volcanic region, in particular the Makka–Madina–Nafud Volcanic (MMNV) line. The maximum t p * values were observed in the southern region of the Arabian Shield, at the southern part of the Red Sea, where the African and Arabian Plates diverge. The observed high t p * will be attributed to the previously revealed low-velocity anomaly and thermal activities beneath the Arabian Shield, and it is also correlated with the topography (high elevation) in the region. [ABSTRACT FROM AUTHOR]

In this article, we propose a succinct data structure of zero-suppressed binary decision diagrams (ZDDs). A ZDD represents sets of combinations efficiently and we can perform various set operations on the ZDD without explicitly extracting combinations. Thanks to these features, ZDDs have been applied to web information retrieval, information integration, and data mining. However, to support rich manipulation of sets of combinations and update ZDDs in the future, ZDDs need too much space, which means that there is still room to be compressed. The paper introduces a new succinct data structure, called DenseZDD, for further compressing a ZDD when we do not need to conduct set operations on the ZDD but want to examine whether a given set is included in the family represented by the ZDD, and count the number of elements in the family. We also propose a hybrid method, which combines DenseZDDs with ordinary ZDDs. By numerical experiments, we show that the sizes of our data structures are three times smaller than those of ordinary ZDDs, and membership operations and random sampling on DenseZDDs are about ten times and three times faster than those on ordinary ZDDs for some datasets, respectively. [ABSTRACT FROM AUTHOR]

Link puzzles involve finding paths or a cycle in a grid that satisfy given local and global properties. This paper proposes algorithms that enumerate solutions and instances of two link puzzles, Slitherlink and Numberlink, by zero-suppressed binary decision diagrams (ZDDs). A ZDD is a compact data structure for a family of sets provided with a rich family of set operations, by which, for example, one can easily extract a subfamily satisfying a desired property. Thanks to the nature of ZDDs, our algorithms offer a tool to assist users to design instances of those link puzzles. [ABSTRACT FROM AUTHOR]