An Empirical Study of Real-World SPARQL Queries

Understanding how users tailor their SPARQL queries is crucial when designing query evaluation engines or fine-tuning RDF stores with performance in mind. In this paper we analyze 3 million real-world SPARQL queries extracted from logs of the DBPedia and SWDF public endpoints. We aim at finding which are the most used language elements both from syntactical and structural perspectives, paying special attention to triple patterns and joins, since they are indeed some of the most expensive SPARQL operations at evaluation phase. We have determined that most of the queries are simple and include few triple patterns and joins, being Subject-Subject, Subject-Object and Object-Object the most common join types. The graph patterns are usually star-shaped and despite triple pattern chains exist, they are generally short.Comment: 1st International Workshop on Usage Analysis and the Web of Data (USEWOD2011) in the 20th International World Wide Web Conference (WWW2011), Hyderabad, India, March 28th, 201

Simulating FRSN P Systems with Real Numbers in P-Lingua on sequential and CUDA platforms

Fuzzy Reasoning Spiking Neural P systems (FRSN P systems, for short) is a variant of Spiking Neural P systems incorporating fuzzy logic elements that make it suitable to model fuzzy diagnosis knowledge and reasoning required for fault diagnosis applications. In this sense, several FRSN P system variants have been proposed, dealing with real numbers, trapezoidal numbers, weights, etc. The model incorporating real numbers was the first introduced [13], presenting promising applications in the field of fault diagnosis of electrical systems. For this variant, a matrix-based algorithm was provided which, when executed on parallel computing platforms, fully exploits the model maximally parallel capacities. In this paper we introduce a P-Lingua framework extension to parse and simulate FRSN P systems with real numbers. Two simulators, implementing a variant of the original matrix-based simulation algorithm, are provided: a sequential one (written in Java), intended to run on traditional CPUs, and a parallel one, intended to run on CUDAenabled devices.Ministerio de Economía y Competitividad TIN2012-3743

TOWARDS AN INTEGRATIVE THEORETICAL FRAMEWORK OF INTERACTIVE MACHINE LEARNING SYSTEMS

Interactive machine learning (IML) is a learning process in which a user interacts with a system to iteratively define and optimise a model. Although recent years have illustrated the proliferation of IML systems in the fields of Human-Computer Interaction (HCI), Information Systems (IS), and Computer Science (CS), current research results are scattered leading to a lack of integration of existing work on IML. Furthermore, due to diverging functionalities and purposes IML systems can refer to, an uncertainty exists regarding the underlying distinct capabilities that constitute this class of systems. By reviewing extensive IML literature, this paper suggests an integrative theoretical framework for IML systems to address these current impediments. Reviewing 2,879 studies in leading journals and conferences during the years 1966-2018, we found an extensive range of applications areas that have implemented IML systems and the necessity to standardise the evaluation of those systems. Our framework offers an essential step to provide a theoretical foundation to integrate concepts and findings across different fields of research. The main contribution of this paper is organising and structuring the body of knowledge in IML for the advancement of the field. Furthermore, we suggest three opportunities for future IML research. From a practical point of view, our integrative theoretical framework can serve as a reference guide to inform the design and implementation of IML systems

Parallel simulation of Population Dynamics P systems: updates and roadmap

Population Dynamics P systems are a type of multienvironment P systems that serve as a formal modeling framework for real ecosystems. The accurate simulation of these probabilisticmodels, e.g. with Direct distribution based on Consistent Blocks Algorithm, entails large run times. Hence, parallel platforms such as GPUs have been employed to speedup the simulation. In 2012, the first GPU simulator of PDP systems was presented. However, it was able to run only randomly generated PDP systems. In this paper, we present current updates made on this simulator, involving an input modu le for binary files and an output module for CSV files. Finally, the simulator has been experimentally validated with a real ecosystem model, and its performance has been tested with two high-end GPUs: Tesla C1060 and K40.Ministerio de Economía y Competitividad TIN2012-37434Junta de Andalucía P08-TIC-0420

The Reduction Problem in CUDA and Its Simulation with P Systems

We introduce P systems with dynamic communication graphs which simu- late the functioning of the CUDA architecture when solving the parallel reduction prob- lem

Morphology and Solubility Products of Calcium Arsenates Found in Arsenic Contaminated Soils in an Abandoned Smelter

"The dissolution of calcium arsenates in residues released on the premises of an inactive smelter has caused high levels of arsenic pollution in the adjacent down-gradient 6 km of a perched aquifer, reaching up to 158 mg/L of dissolved arsenic, and releasing a total of 7.5 tons of arsenic in a year. We characterized the morphology of the calcium arsenates responsible of this pollution and determined their thermodynamic solubility products by (1) following the dissolution of arsenic from soil samples in batch reactors until equilibrium was reached and (2) modeling dissolution data using the geochemical code PHREEQC. Solubility product calculations took into account soil solution chemistry. Our results provide critical thermodynamic data to better understand interactions between water and arsenic containing minerals in the environment.

A software tool for verification of Spiking Neural P Systems

The formal verification of a Spiking Neural P System (SN P Systems, for short) designed for solving a given problem is usually a hard task. Basically, the verification process consists of the search of invariant formulae such that, once proved their validity, show the right answer to the problem. Even though there does not exist a general methodology for verifying SN P Systems, in (Pa˘un et al., Int J Found Comput Sci 17(4):975– 1002, 2006) a new tool based on the transition diagram of the P system has been developed for helping the researcher in the search of invariant formulae. In this paper we show a software tool which allows to generate the transition diagram of an SN P System in an automatic way, so it can be considered as an assistant for the formal verification of such computational devices.Ministerio de Educación y Ciencia TIN2006-13425Junta de Andalucía TIC-58

Simulating a Family of Tissue P Systems Solving SAT on the GPU

In order to provide e cient software tools to deal with large membrane systems, high-throughput simulators are required. Parallel computing platforms are good candidates, since they are capable of partially implementing the inherently parallel nature of the model. In this concern, today GPUs (Graphics Processing Unit) are considered as highly parallel processors, and they are being consolidated as accelerators for scienti c applications. In fact, previous attempts to design P systems simulators on GPUs have shown that a parallel architecture is better suited in performance than traditional single CPUs. In 2010, a GPU-based simulator was introduced for a family of P systems with active membranes solving SAT in linear time. This is the starting point of this paper, which presents a new GPU simulator for another polynomial-time solution to SAT by means of tissue P systems with cell division, trading space for time. The aim of this simulator is to further study which ingredients of di erent P systems models are well suited to be managed by the GPU.Junta de Andalucía P08-TIC04200Ministerio de Economía y Competitividad TIN2012-3743

Emerging audiovisual formats for MOOCs: Informative, educative and advertising design

Audiovisual formats are essential for virtual learning. Videos in MOOC courses exercise an informative, educational, and advertising function in the course program and in social networks. In this article, videos for courses are reviewed critically and include proposals for improvement. Videos of 50 courses of the edX platform are analyzed from the point-of-view of the narrative design of their content and audiovisual components. The results show that MOOC videos have a master lesson structure, with the visual and sound codes of classroom lectures. Solutions that incorporate creative languages and audiovisual technologies used in film and television are proposed