1  Abstract—Linear constraint transformation is an essential step to solve the forbidden state problem in Petri nets that contain uncontrollable transitions. This work studies the equivalent transformation from a legal-marking set to its admissible-marking set given such a net. First, the concepts of an escaping-marking set and a transforming marking set are defined. Based on them, two algorit...

A practical and robust inter-domain marking scheme for IP traceback is proposed. We first identify six drawbacks of Probabilistic Packet Marking (PPM), and then contrive a synergic scheme to address all of them. To relieve the victim from the daunting computational overhead, we derive the optimal marking probability with respect to the number of packets required for path reconstruction, and exp...

Marking student responses to short answer questions raises particular issues for human markers, as well as for automatic marking systems. In this paper we present the Amati system, which aims to help human markers improve the speed and accuracy of their marking. Amati supports an educator in incrementally developing a set of automatic marking rules, which can then be applied to larger question ...

We investigated sexual and seasonal patterns in scent-marking behaviour of the honey badger, by direct observations of habituated individuals (five females, four adult males, two young males). Four categories of scent-marking behaviour were identified: (1) scent marking at latrines; (2) token urination in holes along the foraging path; (3) squat marking at single-use sites; and (4) functional e...

BACKGROUND Peer marking is an important skill for students, helping them to understand the process of learning and assessment. This method is increasingly used in medical education, particularly in formative assessment. However, the use of peer marking in summative assessment is not widely adopted because many teachers are concerned about biased marking by students of their peers. OBJECTIVE T...

H2AZ is a widely conserved histone variant that is implicated in protecting euchromatin from the spread of heterochromatin. H2AZ is incorporated into nucleosomes as a heterodimer with H2B, by the SWR1 ATP-dependent chromatin-remodeling complex. We have identified a homolog of H2AZ in the protozoan parasite Trypanosoma brucei, along with a novel variant of histone H2B (H2BV) that shares approxim...