Cost Estimation for Factorized Machine Learning

In the realm of machine learning (ML), the need for efficiency in training processes is paramount. The conventional first step in an ML workflow involves collecting data from various sources and merging them into a single table, a process known as materialization, which can introduce inefficiencies caused by redundant data. Factorized ML strives...

Efficient Execution of User-Provided Graph Algorithms in a Graph Database

Graph databases are systems to efficiently store and query large graphs. As graph databases grow in popularity, they are used to answer increasingly diverse and complex queries. However, graph databases typically have a very limited query language that cannot express arbitrary algorithms. As a result, many users treat the database as a storage...

Uncovering the Secrets of the Maven Repository: Analysis of Library Sizes in Maven Central

This research explores the size variations of artifacts in Maven Central, a repository containing a large collection of Java artifacts. This analysis sheds light on the coding habits and dependency management ecosystems within Maven Central, emphasizing the importance of managing artifact sizes effectively. It also provides valuable insights to...

Uncovering Secrets of the Maven Repository: Maven packaging

Maven, a widely adopted software ecosystem for Java libraries, plays a critical role in the development and deployment of software applications. However, there exists a limited understanding of the composition and characteristics of the Maven repository, leaving users and contributors unaware of the contents they interact with. This research...

Dead Links and Lost Code: Investigating the State of Source Code Repositories in Maven Central Repository Packages: An Empirical Study

Maven Central serves as the de-facto repository for distributing free and open-source Java libraries and components. Evaluating its present state and overall robustness is pivotal for enabling the community to make well-informed decisions concerning its future progression. Such informed decisions would undoubtedly benefit the collective...

Uncovering secrets of the Maven Repository: Java Build Aspects: An empirical analysis

The Maven Central Repository hosts over 11 million packages. As Maven itself is a build tool for Java, the majority of these packages are Java archives.<br/>This research aims to analyze these packages and look into various build aspects of these projects (the research questions): are Java modules used, what Java versions are used and how is the...

Multi-Source Data Modelling to Understand the Effects of Tourism Demand on Air Quality in Italy

The goal of this research is to model and understand the effects of tourism demand on air quality by performing data integration on multi-source data. This research is aimed at researchers and practitioners aiming to perform multidisciplinary research in the fields of data science and geoscience, presenting the methods and challenges that arise...

An LC-to-camera communication system with ambient light

The current wireless networks can face congestion issues due to the increasing number of digital devices. One way to overcome this is to establish communica-tion at a different range of frequencies, specifically in visible light. Most studies in Visible Light Communication (VLC) systems use active light sources like LEDs for transmission, but...

Non-invasive Characterization of Out-Of-Bounds Write Vulnerabilities

As more and more aspects of our society and economy rely on software, security vulnerabilities in programs have become an increasingly significant threat. One such class of vulnerabilities are out-of-bounds writes, which are still one of the most widespread and dangerous types of security bugs in memory-unsafe programming languages five decades...

Dataflow Analysis in a Language Workbench

Dataflow analysis is a powerful tool used for program optimization, static analysis, and editor services for many programming languages. Spoofax, a language workbench, contains a domain-specific language called FlowSpec for the definition of control-flow and dataflow semantics that language developers can use to implement dataflow analyses for...

Heuristic Augmentation of SAT Solvers for MRCPSP

The multi-mode resource-constrained project scheduling problem (MRCPSP) is an NP-hard scheduling problem that concerns activities with several execution modes connected by precedence relations. Precedence relations define a partial ordering in which activities must be processed. The execution mode of an activity defines its processing time and...

Domain-specific heuristic augmentation of SAT solvers on prize-collecting job scheduling problem

We study the prize-collecting job scheduling problem with one common and multiple secondary resources, where the target is to collect the biggest score possible by constructing a feasible schedule with given constraints of jobs and resources. Many scheduling configurations, where a single asset can be used by all jobs separately and a set of...

SAT-based optimisation for the resource-constrained project scheduling problem with time-dependent resource capacities and requests

In this paper, a variant of the resource-constrained project scheduling problem is discussed. This variant introduces time-dependence for resource capacities and requests, making the problem a more realistic model for many practical applications such as production scheduling and medical research project planning. The main aim of this paper is to...

Exploring Heuristic Methods for the Resource-Constrained Project Scheduling Problem with Logical Constraints

This paper presents the use of a heuristic solution method to improve the process of creating a conjunctive normal form (CNF) encoding of and finding optimal solutions to instances of the resource-constrained project scheduling problem with logical constraints (RCPSP-Log).<br/><br/>The RCPSP is an optimisation problem consisting of a set of...

Resource-constraint project scheduling with task preemption and setup times by Boolean satisfiability encoding and satisfiability (SAT) solver

Scheduling has been subject to much research. The resource-constrained project scheduling problem (RCPSP) is no exception. With the multiple different variations and additions to the standard definition that are possible, many exact, heuristic and meta-heuristic approaches have been proposed. One of those variations is allowing tasks in the...