Hidden Markov Models and their Application for Predicting Failure Events

We show how Markov mixed membership models (MMMM) can be used to predict the degradation of assets. We model the degradation path of individual assets, to predict overall failure rates. Instead of a separate distribution for each hidden state, we use hierarchical mixtures of distributions in the exponential family. In our approach the observation distribution of the states is a finite mixture distribution of a small set of (simpler) distributions shared across all states. Using tied-mixture observation distributions offers several advantages. The mixtures act as a regularization for typically very sparse problems, and they reduce the computational effort for the learning algorithm since there are fewer distributions to be found. Using shared mixtures enables sharing of statistical strength between the Markov states and thus transfer learning. We determine for individual assets the trade-off between the risk of failure and extended operating hours by combining a MMMM with a partially observable Markov decision process (POMDP) to dynamically optimize the policy for when and how to maintain the asset.Comment: Will be published in the proceedings of ICCS 2020; @Booklet{EasyChair:3183, author = {Paul Hofmann and Zaid Tashman}, title = {Hidden Markov Models and their Application for Predicting Failure Events}, howpublished = {EasyChair Preprint no. 3183}, year = {EasyChair, 2020}

ConfBits: A Web Based Conference Management System

ConfBits is a Web-based Conference Management System (CMS) developed to aid effective organization and management of professional, academic and technical conferences. The web based application is an object-oriented and multi-conferences platform that is made up of four major actors which are authors, reviewers, administrators (otherwise known as Program Committee (PC) chair) and participants. Conference organizers in any Anglophone country can subscribe to the platform via the Internet to access and utilize the different features which include; abstract and full paper submissions, assignment of papers to reviewers, sending email notifications to authors and reviewers, participants management and conference program scheduling. The prototype of the platform is already deployed on the Internet and the trial Universal Resource Locator (URL) is www.cucms.com.ng. From our review of existing online CMSs, ConfBits (although still at a prototype stage) is the first of such system from a developing clime. We hope the platform will serve to bridge the hitherto wide digital divide between the developed and developing nations especially with respect to scholarly online content

What is a proof? What should it be?

Mathematical proofs should be paired with formal proofs, whenever feasible.Comment: 4 page

Describing Papers and Reviewers' Competences by Taxonomy of Keywords

This article focuses on the importance of the precise calculation of similarity factors between papers and reviewers for performing a fair and accurate automatic assignment of reviewers to papers. It suggests that papers and reviewers' competences should be described by taxonomy of keywords so that the implied hierarchical structure allows similarity measures to take into account not only the number of exactly matching keywords, but in case of non-matching ones to calculate how semantically close they are. The paper also suggests a similarity measure derived from the well-known and widely-used Dice's coefficient, but adapted in a way it could be also applied between sets whose elements are semantically related to each other (as concepts in taxonomy are). It allows a non-zero similarity factor to be accurately calculated between a paper and a reviewer even if they do not share any keyword in common