Mixed Spatial and Nonspatial Problems in Location Based Services

With hundreds of millions of users reporting locations and embracing mobile technologies, Location Based Services (LBSs) are raising new challenges. In this dissertation, we address three emerging problems in location services, where geolocation data plays a central role. First, to handle the unprecedented growth of generated geolocation data, existing location services rely on geospatial database systems. However, their inability to leverage combined geographical and textual information in analytical queries (e.g. spatial similarity joins) remains an open problem. To address this, we introduce SpsJoin, a framework for computing spatial set-similarity joins. SpsJoin handles combined similarity queries that involve textual and spatial constraints simultaneously. LBSs use this system to tackle different types of problems, such as deduplication, geolocation enhancement and record linkage. We define the spatial set-similarity join problem in a general case and propose an algorithm for its efficient computation. Our solution utilizes parallel computing with MapReduce to handle scalability issues in large geospatial databases. Second, applications that use geolocation data are seldom concerned with ensuring the privacy of participating users. To motivate participation and address privacy concerns, we propose iSafe, a privacy preserving algorithm for computing safety snapshots of co-located mobile devices as well as geosocial network users. iSafe combines geolocation data extracted from crime datasets and geosocial networks such as Yelp. In order to enhance iSafe's ability to compute safety recommendations, even when crime information is incomplete or sparse, we need to identify relationships between Yelp venues and crime indices at their locations. To achieve this, we use SpsJoin on two datasets (Yelp venues and geolocated businesses) to find venues that have not been reviewed and to further compute the crime indices of their locations. Our results show a statistically significant dependence between location crime indices and Yelp features. Third, review centered LBSs (e.g., Yelp) are increasingly becoming targets of malicious campaigns that aim to bias the public image of represented businesses. Although Yelp actively attempts to detect and filter fraudulent reviews, our experiments showed that Yelp is still vulnerable. Fraudulent LBS information also impacts the ability of iSafe to provide correct safety values. We take steps toward addressing this problem by proposing SpiDeR, an algorithm that takes advantage of the richness of information available in Yelp to detect abnormal review patterns. We propose a fake venue detection solution that applies SpsJoin on Yelp and U.S. housing datasets. We validate the proposed solutions using ground truth data extracted by our experiments and reviews filtered by Yelp.

Developmental and physical-fitness associations with gross motor coordination problems in peruvian children

he aims of this cross-sectional study were to examine the developmental characteristics (biological maturation and body size) associated with gross motor coordination problems in 5193 Peruvian children (2787 girls) aged 6–14 years from different geographical locations, and to investigate how the probability that children suffer with gross motor coordination problems varies with physical fitness. Children with gross motor coordination problems were more likely to have lower flexibility and explosive strength levels, having adjusted for age, sex, maturation and study site. Older children were more likely to suffer from gross motor coordination problems, as were those with greater body mass index. However, more mature children were less likely to have gross motor coordination problems, although children who live at sea level or at high altitude were more likely to suffer from gross motor coordination problems than children living in the jungle. Our results provide evidence that children and adolescents with lower physical fitness are more likely to have gross motor coordination difficulties. The identification of youths with gross motor coordination problems and providing them with effective intervention programs is an important priority in order to overcome such developmental problems, and help to improve their general health status.

The Notion of the “Concept Instance”: Problems in Modeling Concept Change in SKOS

The U.S. National Science Foundation metadata registry under development for the National Science Digital Library (NSDL) is a repertory intended to manage both metadata schemes and schemas. The focus of this draft discussion paper is on the scheme side of the development work. In particular, the concern of the discussion paper is with issues around the creation of historical snapshots of concept changes and their encoding in SKOS. Through framing the problem as we see it, we hope to find an optimal solution to our need for a SKOS encoding of these snapshots. Since what we are seeking to model is concept change, it is necessary at the outset to make it clear that we are not talking about changes to a concept of such a nature that would require the declaration a new concept with its own URI.In the project, we avoid the use of the terms “version” and “versioning” with regard to changes in concepts and reserve their use to the significant changes of schemes as a whole. Significant changes triggering a new scheme version might include changes in scheme documentation that express a significant shift in the purpose, use or architecture of the scheme. We use the term “snapshot” to denote the state of a scheme at identifiable points in time. Thus, snapshots are identifiable views of a scheme that record the incremental changes that have occurred to concepts, relationships among concepts, and scheme documentation since the last snapshot. Aspects of concept change occur that we need to capture and make available both through the registry and through potentially in transmission of a scheme to other registries. We call these capturings “concept instances.”

Developmental and physical-fitness associations with gross motor coordination problems in peruvian children

he aims of this cross-sectional study were to examine the developmental characteristics (biological maturation and body size) associated with gross motor coordination problems in 5193 Peruvian children (2787 girls) aged 6–14 years from different geographical locations, and to investigate how the probability that children suffer with gross motor coordination problems varies with physical fitness. Children with gross motor coordination problems were more likely to have lower flexibility and explosive strength levels, having adjusted for age, sex, maturation and study site. Older children were more likely to suffer from gross motor coordination problems, as were those with greater body mass index. However, more mature children were less likely to have gross motor coordination problems, although children who live at sea level or at high altitude were more likely to suffer from gross motor coordination problems than children living in the jungle. Our results provide evidence that children and adolescents with lower physical fitness are more likely to have gross motor coordination difficulties. The identification of youths with gross motor coordination problems and providing them with effective intervention programs is an important priority in order to overcome such developmental problems, and help to improve their general health status.

numerical problems in the calculation of electric field and charge density profiles for mass impregnated non-draining hvdc cables subjected to fast polarity reversals

The goal of this simulation thesis is to present a tool for studying and eliminating various numerical problems observed while analyzing the behavior of the MIND cable during fast voltage polarity reversal. The tool is built on the MATLAB environment, where several simulations were run to achieve oscillation-free results. This thesis will add to earlier research on HVDC cables subjected to polarity reversals. Initially, the code does numerical simulations to analyze the electric field and charge density behavior of a MIND cable for certain scenarios such as before, during, and after polarity reversal. However, the primary goal is to reduce numerical oscillations from the charge density profile. The generated code is notable for its usage of the Arithmetic Mean Approach and the Non-Uniform Field Approach for filtering and minimizing oscillations even under time and temperature variations.

Typed behavioural equivalences in the Pi-Calculus

In this thesis, I study the notion of program equivalences, i.e. proving that two programs can be used interchangeably without altering the overall observable behaviour. This definition is highly dependent on the contexts in which these programs can be used; does the context have exceptions, parallelism, etc... So proofs also need to be adapted according to the expressiveness of those contexts. This thesis presents on the pi-calculus – a concurrent programming language – under various typing constraints. Types allows us to impose different disciplines like forcing a sequential execution, or ensuring linearity, meaning an object can be used once. In each case, the bisimulation, a standard proof technique for the pi-calculus, needs to be adapted accordingly to obtain a suitable equivalence. We then test how using the modified bisimulations can be used to reason about a language with higher-order functions and references, which once translated into the pi-calculus satisfies the typing constraints.

Understanding food waste through behavioural theories in different settings

SDG 12.3 aims to promote sustainable consumption and production patterns by addressing the global food loss and waste problem. Given the multiple interrelated impacts, food waste is recognized as one of the major food system challenges. The scope of this work is to contribute to the understanding on food waste generation and potential approaches to tackle it. This work was specifically designed to achieve the following goals: 1) Understand specific factors that affect individual behaviours to generate FW at household, 2) Analyse the effective ways to reduce FW through behaviour change perspective given the catering and hospitality sector, and 3) Provide an evidence synthesis on intervention study that incorporate stakeholder insights focus on school meals. The first goal of identifying food waste drivers was achieved by the systematically reviewing on peer-reviewed and grey literature. The Motivation-Opportunity-Ability (MOA) framework was applied to frame consumer behavioural drivers and identify levers that could be potentially utilized to reduce food waste. Consumer segmentation was further discussed to provide insights for developing tailored food waste reduction interventions. The second goal required the identification on practical interventions, which has been accomplished by systematic literature review basing on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The efficiency and working mechanism of interventions were evaluated basing on the combination of MOA and behavioural change wheel. Building on the evidence of effective interventions, a roadmap was developed for policymakers and practitioners to lead their own pathway on intervention study and upscaling. The third aim has been achieved with a school meals interventions mapping and the implementation of stakeholder workshops. The method was built on the literature review and then enriched by intervention co-design dialogue among stakeholders. The overall conclusion addressed challenges of food waste determents identification, tailored reduction interventions developing, sustainable consumption promotion with school meals.

Data driven regularization models of non-linear ill-posed inverse problems in imaging

Imaging technologies are widely used in application fields such as natural sciences, engineering, medicine, and life sciences. A broad class of imaging problems reduces to solve ill-posed inverse problems (IPs). Traditional strategies to solve these ill-posed IPs rely on variational regularization methods, which are based on minimization of suitable energies, and make use of knowledge about the image formation model (forward operator) and prior knowledge on the solution, but lack in incorporating knowledge directly from data. On the other hand, the more recent learned approaches can easily learn the intricate statistics of images depending on a large set of data, but do not have a systematic method for incorporating prior knowledge about the image formation model. The main purpose of this thesis is to discuss data-driven image reconstruction methods which combine the benefits of these two different reconstruction strategies for the solution of highly nonlinear ill-posed inverse problems. Mathematical formulation and numerical approaches for image IPs, including linear as well as strongly nonlinear problems are described. More specifically we address the Electrical impedance Tomography (EIT) reconstruction problem by unrolling the regularized Gauss-Newton method and integrating the regularization learned by a data-adaptive neural network. Furthermore we investigate the solution of non-linear ill-posed IPs introducing a deep-PnP framework that integrates the graph convolutional denoiser into the proximal Gauss-Newton method with a practical application to the EIT, a recently introduced promising imaging technique. Efficient algorithms are then applied to the solution of the limited electrods problem in EIT, combining compressive sensing techniques and deep learning strategies. Finally, a transformer-based neural network architecture is adapted to restore the noisy solution of the Computed Tomography problem recovered using the filtered back-projection method.

Problems in physics and mathematics contexts with middle and high school classes: vertical and horizontal comparison

My thesis falls within the framework of physics education and teaching of mathematics. The objective of this report was made possible by using geometrical (in mathematics) and qualitative (in physics) problems. We have prepared four (resp. three) open answer exercises for mathematics (resp. physics). The test batch has been selected across two different school phases: end of the middle school (third year, 8\textsuperscript{th} grade) and beginning of high school (second and third year, 10\textsuperscript{th} and 11\textsuperscript{th} grades respectively). High school students achieved the best results in almost every problem, but 10\textsuperscript{th} grade students got the best overall results. Moreover, a clear tendency to not even try qualitative problems resolution has emerged from the first collection of graphs, regardless of subject and grade. In order to improve students' problem-solving skills, it is worth to invest on vertical learning and spiral curricula. It would make sense to establish a stronger and clearer connection between physics and mathematical knowledge through an interdisciplinary approach.

Working Together To Reduce The Harms Caused By Alcohol Misuse: Report of the Working Group on Alcohol Misuse

The overall aim of the National Alcohol Policy, launched in 1996, is to reduce the level of alcohol-related problems and to promote moderation for those who wish to drink. This report complements the work of the Strategic Task Force on Alcohol (STFA) which takes primarily a public health approach as outlined in paragraph 1.1 of the Second Report of the STFA which states that â?othis approach, endorsed by the WHO, recognises that alcohol contributes to a range of health, social and behavioural problems- in terms of its toxicity, its potential to create dependency and its negative impact on human behaviour. The overall level of alcohol consumption and the predominant pattern of drinking in the population, are predictive of alcohol problems in any given society. Therefore, alcohol policy must take into account the total drinking population when defining the scope of public health action as well targeting high risk groups and individual high risk drinkers.â?Âù Download the Report (PDF, 202kb)

Nuorten koherenssin tunne: mittaaminen, ennustavat tekijät, seuraukset

Sense of coherence in adolescence: measuring, predictive factors, consequences The aim of this study was to explore the stability of sense of coherence (SOC) in adolescence and the associations between childhood psychological symptoms and SOC in adolescence. Furthermore, the aim of this study was to explore whether the 13-item SOC scale for adults is applicable to adolescents 12 years of age and to determine which factors are associated with perceived health and SOC. Data relating to SOC and factors associated with perceived health and SOC were collected in class in a cross-sectional setting by self-administered questionnaires in all publicly funded elementary schools (N=35) of Turku. A total of 1 231 (83%) of 1 481 12-year-old schoolchildren participated in the study. The data was, with appropriated authority consent, anonymously completed with marks in mathematics, native and first foreign language at the end of sixth class. The examination of stability of SOC in adolescence and the associations between childhood psychological symptoms and SOC was based on data of a prospective population-based mail survey. The source population originated in 11 health authority areas of the Province of Turku and Pori. The study was carried out by using questionnaires at child’s ages of 3, 12, 15, and 18 years. Acceptably completed questionnaires were returned by 1 086 (84%) parents at the child’s age of 3, at the age of 12 by 70% adolescents and parents, at the age of 15, by 66% adolescents and 58% parents, and at the age of 18, by 61.5% adolescents and 61% parents. The results of the study showed that childhood behavioural problems from the age of 3 years predicted poor SOC at the age of 18 years. A poor SOC was associated with psychological symptoms and behavioural problems in adolescence. Contrary to assumptions in Antonovsky’s theory, there was no significant change in SOC between the ages of 15 to 18 years, and the stability of SOC did not depend on initial SOC. Slight fluctuation in SOC scores was seen at the individual level. When studied cross-sectionally, in 12-year-old schoolchildren, insufficient physical exercise, less than excellent marks in mathematics, weak SOC, insufficient social support from teachers, and perceived various problems in class climate associated with perception of poor health. Identification of behavioural problems in early childhood helps to identify the children at risk of ill-being and poor SOC in adolescence since problems seem to persist unchanged until adolescence. The 13-item SOC scale aimed at adults is applicable to adolescents of 12 years of age or older and the SOC scale is a useful tool in identifying adolescents in need of supportive interventions.

Las adicciones a la luz del psicoanálisis, una revisión de literatura

El presente trabajo de grado es una revisión de la literatura que permite hacer un recorrido desde el psicoanálisis acerca de la compleja problemática de las adicciones. Para ello, se revisaron las bases de datos PepWeb, Ebsco, y Jstor, revisando las posiciones del psicoanálisis freudiano, lacaniano y otras corrientes psicoanalíticas respondiendo a las siguientes preguntas de investigación: (a) ¿Cómo se comprenden las adicciones desde un marco de referencia psicoanalítico? (b) ¿Cómo –desde la teoría freudiana y la teoría lacaniana - se aborda la comprensión de la adicción? (c) ¿Qué dice el psicoanálisis contemporáneo sobre ésta problemática? Se abordan temas como la concepción de una adicción desde la perspectiva de Freud y Lacan hasta psicoanalistas contemporáneos, el rol que juega el goce en la adicción y, finalmente, el complejo debate incipiente sobre la legalidad del tóxico. Se encontró que es un campo de constante publicación y es necesario que los clínicos y los psicoanalistas aborden este campo de estudio clínico permanentemente y sigan produciendo investigaciones sobre el fenómeno.

Trabajo infantil y problemas del comportamiento en menores trabajadores

Objetivo: Identificar la relación de los factores de riesgo ocupacional del trabajo infantil con los problemas de comportamiento en menores de edad trabajadores de una plaza de mercado en Colombia Materiales y métodos: Se realizó un estudio de corte transversal con 100 niños trabajadores de la plaza de Mercaneiva. Se aplicó un cuestionario para evaluar los factores ocupacionales en la población, evaluando aspectos sociodemográficos y condiciones laborales; para establecer la prevalencia de los problemas del comportamiento se utilizó el cuestionario sobre el comportamiento de niños niñas de 6-18 años (CBCL- 01). El análisis de los datos se realizó mediante SPSS versión 26, con un análisis estadístico cualitativo por medio de proporciones y tablas de frecuencia, se usaron además medidas de tendencia central y dispersión. Se hizo un análisis bivariado entre los problemas de comportamiento y los factores ocupacionales utilizando el coeficiente de Spearman. Resultados: Se determinaron 3 parámetros relacionados entre los factores ocupacionales y los problemas de conductas que fueron la edad mínima de admisión al empleo (8.2 ± 2.5 años, med=8), las extensas jornadas de trabajo (7.2 ± 3.1, med=7) y los años que lleva laborando (4.5± 2.6 años med=4). Los niños mostraron una diferencias significativa en los problemas de comportamiento (26.3± 9.9) más que las niñas (23.9±9.3) (p=0.023) y respecto a las conductas externalizadas fue mayor en el género masculino (p=0.001). El resultado de la prevalencia de los problemas de comportamiento demostró que el rango clínico se correlacionó significativamente con el comportamiento general (conductas internalizadas r= 0.735, p<0.001; conductas externalizadas r= 0.693, p<0.001; otros problemas r= 0.729, p<0.001) al hallar que el 76.0% de menores trabajadores están en un rango clínico. Conclusión: El empezar a trabajar a una edad temprana es un riesgo para presentar problemas de conducta. Los entes gubernamentales deben ser más activos y apropiarse de su rol para el restablecimiento de derechos y actuar en los resultados hallados en la investigación para que se continúe monitoreando mediante más estudios e intervenciones.

Occupants' adaptive responses and perception of thermal environment in naturally conditioned university classrooms

A year-long field study of the thermal environment in university classrooms was conducted from March 2005 to May 2006 in Chongqing, China. This paper presents the occupants’ thermal sensation votes and discusses the occupants’ adaptive response and perception of the thermal environment in a naturally conditioned space. Comparisons between the Actual Mean Vote (AMV) and Predicted Mean Vote (PMV) have been made as well as between the Actual Percentage of Dissatisfied (APD) and Predicted Percentage of Dissatisfied (PPD). The adaptive thermal comfort zone for the naturally conditioned space for Chongqing, which has hot summer and cold winter climatic characteristics, has been proposed based on the field study results. The Chongqing adaptive comfort range is broader than that of the ASHRAE Standard 55-2004 in general, but in the extreme cold and hot months, it is narrower. The thermal conditions in classrooms in Chongqing in summer and winter are severe. Behavioural adaptation such as changing clothing, adjusting indoor air velocity, taking hot/cold drinks, etc., as well as psychological adaptation, has played a role in adapting to the thermal environment.