Facebook Twitter Gplus Google Maps E-mail

Book Release

This text intends to be a comprehensive and substantially self-contained two-volume book covering performance, reliability, and availability evaluation subjects. The volumes focus on computing systems, although the methods may also be applied to other systems. Like many other parallel or concurrent systems, computing systems often lead to conflicts because processes attempt to access resources simultaneously or with time overlapping. Such conflict may cause errors, process congestion, and system deadlocks. Moreover, when planning a cost-effective system, the policies, mechanisms, systems’ structures, and the respective phenomena are usually hard to represent by deterministic models. On the other hand, such systems commonly have statistical regularities that make them suitable for dealing with stochastic processes and statistics that quantify the collected data’s central tendencies, variability, and shapes. Due to its size, the document was divided into two volumes. The first volume covers from Chapter 1 to Chapter 14, whose subtitle is “Performance Modeling and Background”. The second volume encompasses from Chapter 16 to Chapter 26 and has the subtitle “Reliability and Availability Modeling, Measuring and Workload, and Lifetime Data Analysis”.



 Share on Facebook Share on Twitter Share on Reddit Share on LinkedIn
Comments Off on Book Release  comments 

New Version of Mercury Tool Available!


The version 5.3 of Mercury has been released.


Dear Colleagues,

We are pleased to announce that version 5.3 of the Mercury tool has been released to the industry and academic community.

This new version fixes a number of bugs found in previous versions.

If you are a Mercury user, we strongly recommend that you get the new version.

We hope you will enjoy it. If you have any suggestions or find any bugs, please report them to us.

If you do not know the tool yet and want to try it, please go to www.modcs.org and go to “Downloads” and “Mercury Tool”.

There you will get a form, sign it and download the tool.


Mercury 5.3 – click here to download


What’s new in Mercury?

Below we describe the most important features and enhancements of version 5.3:
  1. Performance improvement when performing evaluations on RBDs and FTs.
  2. Usability improvements.
    1. The editor now highlights the name of the tab of the selected model.
    2. Mercury now supports drag-and-drop rearrangement of model tabs. This allows you to customize the layout of your workspace by simply clicking on a tab and moving it to the desired location. This feature is especially valuable for projects where users frequently work with multiple models and need a flexible way to keep everything well organized and easily accessible.
    3. The editor now provides visual assistance through vertical and horizontal alignment lines when adding, resizing, or moving components on the canvas, ensuring precise alignment.
    4. Users can fine-tune component positioning with the keyboard arrow keys for precise control over element placement.
    5. In addition, users can activate and deactivate the grid mode by pressing the CTRL + G keys. When enabled, this mode draws multiple lines on the canvas to facilitate component alignment.
  3. Mercury exports models to PDF files.
  4. An Expectation-Maximization Auto-fitting (EMA) tool. An  EMA algorithm is a fundamental technique for parameter estimation in statistical models when handling clustered data.  The EMA tool implements an algorithm that provides a robust approach to parameter estimation in complex models. It is suitable for scenarios where data points have unknown probabilities of belonging to different clusters and these clusters follow known distributions with unknown parameters.  The main goal of the EMA tool is to iteratively estimate the parameters for each cluster such that they maximize the likelihood of the observed data.
  5. Mercury exports SPN/CTMC models to the Wolfram Mathematica language/SageMath format. When exporting to Mathematica, Mercury creates the nb file that can be opened in Mathematica.
  6. Some minor improvements and bug fixes.

What is the Mercury tool used for?

Mercury enables a range of models to be created and evaluated for supporting performance and dependability evaluations, such as reliability block diagrams (RBDs), dynamic RBDs (DRBDs), fault trees (FTs), energy flow models (EFMs), stochastic Petri nets (SPNs), and continuous and discrete-time Markov chains (CTMCs and DTMCs).

The tool has been cited in more than 140 scientific publications and used in over 18 countries worldwide.
 Share on Facebook Share on Twitter Share on Reddit Share on LinkedIn
Comments Off on New Version of Mercury Tool Available!  comments 
© MoDCS Research Group