True exact I. Qed.
The first exercise:
Get a root of the polynomial x 3 + 3 x 2 + 4 x + 2 0 using z3. Can you use z3 to show this is the only solution?
Here we open up the reals.
It is easy enough to confirm that the solution of x -1 is a zero using the [ring] tactic.
Require Import Reals.
Open Scope R scope.
Print Scope R scope.
Scope R scope
Delimiting key is R
Bound to class R r ² : Rsqr r x ^ y : pow x y x y : Rge x y x y : Rgt x y x y z : and (Rle x y) (Rle y z)
Date Time
Smaller businesses get help to increase cyber security
Together with six partners, DTU Compute will help Danish software companies to think about IT security in product development, right from the beginning.
Our digital life is amazing. We can shop online, open the front door with our phone and track when and where we go running. We are used to having our information in the cloud with access 24/7. However, all that convenience requires cyber security of the highest quality to secure no one can misuse it. At the same time, the EU imposes increased legal requirements on the security and protection of personal data. IT security is therefore becoming a growing competitive parameter for companies.
Shift2Rail’s ‘4SECURail’ completes initial work on projects towards tightening cyber security and improving signalling systems across European railways
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Barcelona, 17 February 2021 - The two Shift2Rail’s 4SECURail workstreams have reached their mid-term objectives for the design of a Computer Security Incident Response Team (CSIRT) for joint EU-Rail cyber security, and a Formal Methods Demonstrator for improved Railway Signalling Systems.
4SECURail, a two-year Shift2Rail initiative aimed at delivering a co-designed process and tools for information sharing and cooperation for rail cyber security at European level and to support better interoperability of signalling systems for railway security, safety and efficiency, has announced that it has achieved its mid-term objectives for the design of a Computer Security Incident Response Team (CSIRT) for joint EU-Rail cyber security, and a Formal Methods Demonstrator for improved Railway Signalling Systems.
Edmund M. Clarke, University Professor Emeritus
Edmund M. Clarke, University Professor Emeritus at Carnegie Mellon University and co-recipient of the 2007 Turing Award – computer science s equivalent of the Nobel Prize – died Dec. 22 of COVID-19, following a long illness.
Clarke, together with his Harvard University graduate student, E. Allen Emerson, and, working separately, Joseph Sifakis of the University of Grenoble, developed an automated method for detecting design errors in computer hardware and software. Called model checking, it is widely used and has helped to improve the reliability of complex computer chips, systems and networks. The Association for Computing Machinery (ACM) awarded the Turing to the three scientists for this achievement.