The automatic registration of LiDAR data and optical images, which are heterogeneous data sources, has been a major research challenge in recent years. In this paper, a novel hierarchical method is proposed in which the least amount of interaction of a skilled operator is required. Thereby, two shadow extraction schemes, one from LiDAR and the other from high-resolution satellite images, were u...

Hidden encrypted volumes can cause problems in digital investigations since they provide criminal suspects with a range of opportunities for deceptive antiforensics and a countermeasure to legislation written to force suspects to reveal decryption keys. This paper describes how hidden encrypted volumes can be detected, and their size estimated. The paper shows how multiple copies of an encrypte...

Phenomenally strong visual illusions are described in which the motion of an object's cast shadow determines the perceived 3-D trajectory of the object. Simply adjusting the motion of a shadow is sufficient to induce dramatically different apparent trajectories of the object casting the shadow. Psychophysical results obtained with the use of 3-D graphics are reported which show that: (i) the in...

Recently, several soft shadow mapping algorithms have been introduced which extract micro-occluders from a shadow map and backproject them on the light source to approximately determine light visibility. To maintain real-time frame rates, these algorithms often have to resort to coarser levels of a multi-resolution shadow map representation which can lead to visible quality degradations. In par...

this study seeks to examine how teachers’ educational background (those who have educated in tefl in comparison to those who have educated in literature) may influence their beliefs and attitudes on language learning, teaching and the teaching methods they apply in their classes. on a general basis, depending on teachers’ opinion, learning process might be seen as behavioristic, inductive, inte...

A double-sided shadow minimization problem in the Boolean cube layer is investigated in this paper. The problem is to minimize the size of the union of the lower and upper shadows of a k-uniform family of subsets of [n]. It is shown that if 3 ≤ k ≤ n− 3, there is no total order such that all its initial segments have minimal double-sided shadow. Denote by ([n] k ) the family of all subsets of t...

For some computer vision tasks, the presence of shadows in images can cause problems. For example, object tracks can be lost as an object crosses over a shadow boundary. Recently, it has been shown that it is possible to remove shadows from images. Assuming that the location of the shadows are known, shadow-free images are obtained in three steps. First, the image is differentiated. Second, the...