Tactics are commands used to guide goal-directed proofs in interactive proof environments. This paper presents various possible sim-pliications on tactic expression and provides a justiication for these simpliications, based on a precise description of the way tactics operate. In particular, this paper introduces a class of head-oriented tactics that are especially suited for optimization. Most...

Computational reflection is a useful technique for avoiding the overhead inherent in constructing large proof objects. However, to date it is significantly more time consuming to write reflective procedures than the equivalent tactics. Can we build a lightweight tactic language for building reflective procedures easily? To this end, we present Rtac, a lightweight, work-in-progress, tactic langu...

Tactician is a tool for refactoring tactic proof scripts for the HOL Light theorem prover. Its core operations are packaging up a series of tactic steps into a compact proof with tactical connectives, and the reverse operation of unravelling compact proofs into interactive steps. This can be useful for novices learning from legacy proof scripts, as well as for experienced users maintaining thei...

Although there are many studies which have observed the overall impacts of Computer-Mediated Communication (CMC) or Information Systems, and many empirical studies which analysed specific impacts partially, there are few studies which have focused on the overall relationship between CMC management and job satisfaction. Therefore, this study aims to clarify the overall CMC impact framework: CMC ...

HOL-UNITY is an implementation of Chandy and Misra's UNITY theory in the HOL88 and HOL90 theorem provers. This paper shows how to verify safety and progress properties of concurrent programs using HOL-UNITY. As an example it is proved that a lift-control program satisses a given progress property. The proof is compositional and partly automated. The progress property is decomposed into basic sa...

ArcAngel is a specialised tactic language devised to facilitate and automate program developments using Morgan’s refinement calculus. It is especially well-suited for the specification of high-level strategies to derive programs by construction, and equipped with a formal semantics that enables reasoning about tactics. In this paper, we present an implementation of ArcAngel for the ProofPower t...

Higher order logics are expressive tools for tasks ranging from formalizing the foundations of mathematics to large scale soft ware veri cation and synthesis Because of their complexity proofs in higher order logics often use a combination of interactive proving to gether with computationally intensive tactic applications that perform proof automation As problems and proof automation become mor...

The present study was conducted on the sample of 50 workers employed in open cast mines of BCCL, Dhanbad (INDIA). The ultimate aim of the present study was to assess the stressstate and its effect on task performance, job involvement and job satisfaction of workers employed in stress arousing job situations i.e., open cast mines. The following variables were used in the present study: (1) Predi...