Verification of Concurrent Systems : optimality, Scalability and Applicability

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Informática, leída el 14-10-2020Tanto el testing como la verificacion de sistemas concurrentes requieren explorar todos los posibles entrelazados no deterministas que la ejecucion concurrente puede tener, ya que cualquiera de estos entrelazados podra revelar un comportamiento erroneo del sistema. Esto introduce una explosion combinatoria en el numero de estados del programa que deben ser considerados, lo que frecuentemente lleva a un problema computacionalmente intratable. El objetivo de esta tesis es el desarrollo de tecnicas novedosas para el testing y la verificacion de programas concurrentes que permitan reducir esta explosion combinatoria...Both verification and testing of concurrent systems require exploring all possible non-deterministic interleavings that the concurrent execution may have, as any of the interleavings may reveal an erroneous behavior of the system. This introduces a combinatorial explosion on the number of program states that must be considered, what leads often to a computationally intractable problem. The overall goal of this thesis is to investigate novel techniques for testing and verification of concurrent programs that reduce this combinatorial explosion...Fac. de InformáticaTRUEunpu

Deadlock-Guided Testing in CLP

Static deadlock analyzers might be able to verify the absence of deadlock. However, they are usually not able to detect its presence. Also, when they detect a potential deadlock cycle, they provide little (or even no) information on their output. Due to the complex flow of concurrent programs, the user might not be able to find the source of the anomalous behaviour from the abstract information computed by static analysis. This work proposes the combined use of static analysis and testing for effective deadlock detection in asynchronous programs. The asynchronous program is first translated into a CLP-version so that the whole combined approach is carried out by relying on the inherent backtracking mechanism and constraint handling of CLP. When the program features a deadlock, our combined use of analysis and testing provides an effective technique to catch deadlock traces. While if the program does not have deadlock, but the analyzer inaccurately spotted it, we might be able to prove deadlock freedom. The main results in this project have been submitted to: - the special issue on Computational Logic for Verification of the journal Theory and Practice of Logic Programming and - the 27th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR'17), and are currently under revision

Conditioning and backward errors of eigenvalues of homogeneous matrix polynomials under Möbius transformations

We present the first general study on the effect of Möbius transformations on the eigenvalue condition numbers and backward errors of approximate eigenpairs of polynomial eigenvalue problems (PEPs). By usingthe homogeneous formulation of PEPs, we are able to obtain two clear andsimple results. First, we show that if the matrix inducing the Möbius transformation is well-conditioned, then such transformation approximately preservesthe eigenvalue condition numbers and backward errors when they are definedwith respect to perturbations of the matrix polynomial which are small relativeto the norm of the whole polynomial. However, if the perturbations in eachcoefficient of the matrix polynomial are small relative to the norm of that coefficient, then the corresponding eigenvalue condition numbers and backwarderrors are preserved approximately by the Möbius transformations induced bywell-conditioned matrices only if a penalty factor, depending on the norms ofthose matrix coefficients, is moderate. It is important to note that these simple results are no longer true if a non-homogeneous formulation of the PEP isused

Gold Nanoparticles on Yttrium Modified Titania: Support Properties and Catalytic Activity

A series of titanium oxide catalysts modified with yttrium has been prepared by sol¿gel method and their structural properties have been studied. The incorporation of yttrium in the titania lattice favors the formation of oxygen vacancies while at low Y loadings the anatase structure is preserved. The catalytic activity of these solids for CO oxidation is found to be significantly dependent on their physical properties. In particular the amount of dopant controls the number of surface oxygen vacancies created as well as the gold particle size, which directly affects the catalytic activity. Also, a linear relationship between the catalytic activity and the band gap values, which depend on the Y loading, is observed. Density functional theory based calculations show that Y atoms are incorporated at the TiO2 surface at substitutional positions only, while the preferred oxygen vacancies arise by removing the bridge surface oxygen atoms. These O-vacancies are the preferential adsorption sites for Au atoms and nanoparticles, acting as nucleation centers that favor the dispersion of the catalyst active phase over the support surface. In agreement with experiment, Y doping is found to decrease the band gap of the support due to a destabilization of the valence band of the oxide.Ministerio de Ciencia e Innovación ENE2009-14522-C05-01, MAT2008-04918, CSD-00023Junta de Andalucía P08-FQM-0366

Occupational therapy and professional identity: narratives of professionals through life history. study protocol

[Abstract] Project title: Occupational therapy and professional identity: narratives of professionals through life history. Study Protocol. Design: Qualitative research, using a socio-critical paradigm and biographical-narrative method where participants were selected through theoretical sampling and snowball sampling strategy. Data collection techniques were life stories, constructed through biograms, self-reports and biographical interviews. Abductive reasoning was used along with structural analysis techniques, narrative analysis, and ATLAS. ti software. Objective: To describe and analyze the occupational construct of the professional identity of occupational therapists in Spain. Specific Objectives: (1) Analyze life events, transitions, and turning points that contribute to the outlining of the life journey of professional identity. (2) Explore the management of professional tasks. (3) Analyze the nature of the knowledge required to carry out the role. (4) Examine in detail the strategies applied to the personal engagement of occupational therapists. Study Population and Total Number of Participants: The study population consisted of professionals who are currently working as occupational therapists in Spain. The number of participants was established when data saturation was reached, with a total of nine informants

Learning and Development of Diagnostic Reasoning in Occupational Therapy Undergraduate Students

[Abstract] Background/Aim. One way to facilitate occupational therapy undergraduate students transferring their academic skills of data gathering and analysis to professional settings is to ensure they can competently use diagnostic reasoning. Nevertheless, there are several obvious gaps in empirical evidence related to the learning and development of this style of reasoning in occupational therapy undergraduates. The most important are related to promoting higher-order thinking and the use of information to solve problems in the context of professional practice. This study analyses undergraduates’ diagnostic reasoning and its changes during their education. Materials and Methods. This multicentre study was conducted with a descriptive observational design. The study took place at the University of Coruña (Spain), University of Castilla-La Mancha (Spain), and University of el Valle (Colombia). The sample was n = 247. For data collection, a clinical case was specifically designed. IBM SPSS Statistics (v19) and EPIDAT 3.1 were used for the data analysis. Results. Participants identified and categorized occupational performance problems. However, they had difficulties when identifying and categorizing the occupational performance components (specifically, the symptoms and signs of the disease presented in the study case). They presented limitations to analyse and synthesize the information collected to develop an explanation of the occupational problems and their causes. Conclusions. Undergraduate students’ ability to analyse and synthesize information during data collection is poorly organized, so it makes the problem formulation difficult. This study contributes to the knowledge of undergraduates’ diagnostic reasoning features, specifically the undergraduate students’ capacities and limits to process information during the occupational assessment

Analysis of occupational therapy students’ pedagogical practices for the forging of professional identity and development of professional intelligence: a scoping review

Review[Abstract] Pedagogical practices contribute to enhancing professional intelligence which is an indicator of maturity and development of professional identity. The research guiding question was: What are the pedagogical practices involved in occupational therapy students' professional identity formation? A scoping review using a six-stage methodological framework was used to capture a variety of evidence describing how professional identity has been conceptualised and integrated into the occupational therapy curriculum while noticing a link to professional intelligence. Databases included were: Ovid MEDLINE, CINAHL, PsycINFO, ProQuest ERIC, Scopus, Web of Science, CSIC, Dialnet, PubMed, Pubmed Central, OTDBASE and Scielo. Qualitative content analysis was used to categorise learning outcomes into five components of professional identity that were associated with the pedagogical practices identified in the studies. n = 58 peer-reviewed journal articles were recorded. The articles were classified as intervention studies (n = 31; 53.4%), reviews (n = 12; 20.7%) and theoretical articles (n = 15; 25.9%). To ensure the feasibility of collecting and reporting results, we narrowed the focus to n = 31 intervention studies that provided information on pedagogical practices and learning outcomes on professional identity forging in students. This scoping review illustrates the variety of contexts in which students learn, the multiple dimensions of identity establishment, and the variety of pedagogical practices. These findings can be used to adapt and design focused formative curricula that support the development of professional identity

The Effectiveness of Community Occupational Therapy Interventions: A Scoping Review

[Abstract] Background: This review aims to evaluate the level of scientific evidence for the effectiveness of Community Occupational Therapy interventions. Methods: A systematic review was used to analyze and synthesize the studies collected. The databases of Cochrane, OTseeker, OTCATS, Web of Science, Scielo and Scopus were used in order to collect articles published between 2007 and 2020. PRISMA recommendations were followed. Results: A total of 12 articles comprised part of the study (7 randomized controlled studies, 4 systematic reviews and 1 meta-analysis). The main areas of practice were geriatric gerontology (22.1%) and mental health (19.7%), which were statistically significant (χ2; p 7 on the PEDro and AMSTAR scales. Conclusions: Research on Community Occupational Therapy constitutes a consolidated line of research but the objectives and areas of research were limited. Descriptive qualitative methodology predominated and studies on the effectiveness of Community Occupational Therapy interventions showed a medium–low level of evidence

“I feel guilty”. Exploring guilt-related dynamics in family caregivers of people with dementia

Objectives: Family caregivers of people with dementia often report feelings of guilt. However, the number of studies analyzing guilt and the factors associated with its appearance are scarce. The aim of this study is to explore the subjective experience of guilt in the family care of people with dementia. Methods: A qualitative analysis of the narratives of 13 family caregivers of people with dementia about their feelings of guilt was done. Results: Seven categories for understanding guilt in caregiving were obtained: guilt derived from actions themselves; guilt derived from one’s limitations; guilt for feeling negative emotions; guilt associated with the change in the relationship with the person cared for; guilt for neglecting other areas; guilt induced by the person cared for, and guilt induced by others. The results showed the existence of cases in which guilt is absent by distress-avoiding processes. Conclusions: Guilt is a relevant variable in understanding caregiver distress, and its analysis is necessary for therapeutic work in the field of care. Clinical implications: Psychological interventions aimed at family caregivers should include specific techniques in order to address guilt feelings.The study was supported by the Spanish Ministry of Economy and Competiveness (grants PSI2015-65,152-C2-1-R and PSI2015-65,152-C2-2-R

A Q-Method Approach to Perceptions of Professional Reasoning in Occupational Therapy Undergraduates

[Abstract] Background. Professional reasoning provides a firm basis for the development of teaching and assessment strategies to support the acquisition of skills by healthcare students. Nevertheless, occupational therapy educators should use diverse methods of learning assessment to examine student learning outcomes more fully with an evaluation that supports the overall complexity of the process, particularly learners’ subjective experience. The aim of this article is to identify the range of perspectives among occupational therapy undergraduates regarding terms or concepts that are key for improving their professional reasoning. Methods. Q-methodology was used to address the aim of the study. A concourse relating to a series of ideas, phrases, terminology, and concepts associated with various studies on professional reasoning in occupational therapy, specifically on students in this field, was generated. The terms that had the clearest evidence, the most relevance or the greatest number of citations in the literature were collected (n = 37). The P-set was assembled by non-probabilistic sampling for convenience. It comprised undergraduate university students in occupational therapy. Factor analysis was conducted using Ken-Q Analysis v.1.0.6, reducing the number of Q-sets to smaller groups of factors representing a common perspective. Results. Through statistical analysis of the Q-sorts of 37 occupational therapy students, 8 default factors were identified. The four factors in accordance with the selection criteria were rotated by varimax rotation to identify variables that could be grouped together. Each viewpoint was interpreted, discussed and liked to different aspects of professional reasoning in occupational therapy. Conclusions. The observed perceptions were linked to the various aspects of professional reasoning that have been widely discussed in the occupational therapy literature. For most of the students, there was a strong correspondence between the narrative, interactive and conditional aspects of the various components