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Human activity recognition from video sequences has emerged recently as pivotal research area due to its importance in a large number of applications such as real-time surveillance monitoring, healthcare, smart homes, security, behavior analysis, and many more. However, lots of challenges also exist such as intra-class variations, object occlusion, varying illumination condition, complex background, camera motion, etc. In this work, we introduce a novel feature descriptor based on the integration of magnitude and orientation information of optical flow and histogram of oriented gradients which gives an efficient and robust feature vector for the recognition of human activities for real-world environment. In the proposed approach first we computed magnitude and orientation of the optical flow separately then a local-oriented histogram of magnitude and orientation of motion flow vectors are computed using histogram of oriented gradients followed by linear combination feature fusion strategy. The resultant features are then processed by a multiclass Support Vector Machine (SVM) classifier for activity recognition. The experimental results are performed over different publically available benchmark video datasets such as UT interaction, CASIA, and HMDB51 datasets. The effectiveness of the proposed approach is evaluated in terms of six different performance parameters such as accuracy, precision, recall, specificity, $F$-measure, and Matthew’s correlation coefficient (MCC). To show the significance of the proposed method, it is compared with the other state-of-the-art methods. The experimental result shows that the proposed method performs well in comparison to other state-of-the-art methods.

We reappraise the material needed to assess the 20th-century seismicity of Switzerland and of the adjacent areas of the Alps in terms of magnitude. For this we make use of macroseismic reports and literature and by calculating the surface-wave magnitude from the Prague formula of all significant earthquakes in the region. No attempt is made to relocate earthquake positions; instead their reliability is ranked using existing solutions and macroseismic observations. We find that for small earthquakes (M_S<4.5), which constitute the bulk of the events in the region, the calculation of M_S observed at relatively short distances, requires station and distance corrections which can be significant. Also we find that recomputed Ms estimates differ from those reported in other earthquake catalogues. From this reappraisal of M_S and from a uniform re-evaluation of the associated macroseismic data, we derive a stable correlations between M_S and felt areas that can be used to assess the magnitude of historical, pre-instrumental, events for which only isoseismal radii (r_i) and the associated intensities (I_i) are available. We examined the conversion of surface-wave magnitude into moment magnitude, a conversion that presents some interesting problems for relatively small events for which the M_S-log(M₀) scaling changes. We conclude that the rate of moment release derived from events of M_S>4.0 is small, and that it should be associated with horizontal and vertical velocity rates of less than 1 mm/yr, too small to be confirmed by GPS measurements over short periods of time so that can be used to constrain hazard assessment.

This paper is concerned with the calibration of the surface-wave magnitude scale for the European region using the Prague formula. Two issues in particular have been addressed:

• Does the Prague formula require a correction of the distance dependency term?

• Is a source depth correction required?

The issue of distance dependency has been investigated by examining the distance dependency of residuals from individual station M_s magnitudes and "representative" M_s magnitude values. We find that M_s magnitudes determined for the European region, using the Prague formula show slight dependence on recording station distance. The subsequent distance dependency of the mean M_s magnitude determination is therefore a function of the distance distribution of the recording stations.

The question of depth correction has been investigated by examining the regression of M_s magnitudes versus seismic moment as a function of depth. We find that the M_s magnitudes determined by the Prague formula are only valid for crustal events, and require a depth correction for source depths greater than 30 km.

As a by-product of these investigations, we find that for the European region there are stable nonlinear relations between surface-wave magnitude (M_s) and the log of seismic moment (logMo) and vice versa. These relationships will provide suitable functions for the correlation between one source size indicator and the other.

Creativity is a vibrant field of scientific research with important applied implications for the management of innovation. In this article, we argue that the proliferation of creativity research has led to positive and less positive outcomes and discuss five relevant research themes. We first introduce our readers to the different proposed dimensions of a creative object. Next, we explain recent developments on the level of the creativity magnitude issue. Based on that, we review how researchers currently operationalize creativity. After discussing how creativity is conceptualized and operationalized, we outline how it might be enhanced. Finally, we present an overview of the wide variety of methodological approaches currently used in creativity research. We close by calling for more interdisciplinary research and offering other suggestions for future directions.

Creativity is a vibrant field of scientific research with important applied implications for the management of innovation. In this chapter, we argue that the proliferation of creativity research has led to positive and less positive outcomes and discuss five relevant research themes. We first introduce our readers to the different proposed dimensions of a creative object. Next, we explain recent developments on the level of the creativity magnitude issue. Based on this, we review how researchers currently operationalize creativity. After discussing how creativity is conceptualized and operationalized, we outline how it might be enhanced. Finally, we present an overview of the wide variety of methodological approaches currently used in creativity research. We close by calling for more interdisciplinary research and offering other suggestions for future directions.