The Descriptions and Attitudes of Riders and Arena Owners to 656 Equestrian Sport Surfaces in Sweden

Horses in equestrian sports are commonly trained in arenas with prepared footing. Information on the number and variants of such arenas is generally unknown. This paper provides an overview of the primary construction types of riding surfaces in Sweden including details on composition, constructions principles, usage frequency, maintenance, and cost of operation as well as to investigate rider perception of the ideal arena properties using a large population of riders. Data on 656 equestrian surfaces in Sweden obtained up to 2014 are presented, of which 373 were outdoor and 283 were indoor arenas. Dressage and show-jumping were the main disciplines conducted in the arenas. Sand-mineral arenas were most common outdoors and sand-woodchips arenas most common indoors, followed by sand-fibre arenas and even fewer synthetic arenas. Comparing the three most common arena types, dragging was most often done on sand-woodchips and sand-fibre arenas. Harrowing was less often done on sand-mineral arenas compared to sand-woodchips and sand-fibre arenas. Combining dragging, harrowing, deep harrowing, and rolling, arenas with higher usage were maintained more frequently, compared to those used less frequently. It was commonly claimed that the top-layer needs renovation every other-4th year or every 5th to 10th year. Few respondents allocated more than 10,000 SEK in yearly maintenance costs, with the exception for sand-woodchips and sand-fibre arenas followed by synthetic arenas. The shortest duration perceived between required renovations was found for sand-woodchips top-layer arenas. Ideal surface properties were evaluated by 3,158 riders. Dressage and show-jumping riders differed somewhat regarding ideal spans of functional arena properties: for impact firmness, responsiveness, and grip. The current study likely included well-utilised arenas, compared to those less well-utilised. The resources necessary to keep an arena consistent over time seemed underestimated. Knowledge of maintenance and priorities for arenas are important to users and arenas managers, be they construction companies or arena managers in order to maximise the outcome of efforts for arena improvement and optimise locomotor health for horses that use them. Further, many arenas were new and research into organic arena management is important, especially if equestrians continue to build and renew arena surfaces

Relative immaturity and ADHD : findings from nationwide registers, parent- and self-reports

BACKGROUND: We addressed if immaturity relative to peers reflected in birth month increases the likelihood of ADHD diagnosis and treatment. METHODS: We linked nationwide Patient and Prescribed Drug Registers and used prospective cohort and nested case-control designs to study 6-69 year-old individuals in Sweden from July 2005 to December 2009 (Cohort 1). Cohort 1 included 56,263 individuals diagnosed with ADHD or ever used prescribed ADHD-specific medication. Complementary population-representative cohorts provided DSM-IV ADHD symptom ratings; parent-reported for 10,760 9-year-old twins born 1995-2000 from the CATSS study (Cohort 2) and self-reported for 6,970 adult twins age 20-47 years born 1959-1970 from the STAGE study (Cohort 3). We calculated odds ratios (OR:s) for ADHD across age for individuals born in November/December compared to January/February (Cohort 1). ADHD symptoms in Cohorts 2 and 3 were studied as a function of calendar birth month. RESULTS: ADHD diagnoses and medication treatment were both significantly more common in individuals born in November/December versus January/February; peaking at ages 6 (OR: 1.8; 95% CI: 1.5-2.2) and 7 years (OR: 1.6; 95% CI: 1.3-1.8) in the Patient and Prescribed Drug Registers, respectively. We found no corresponding differences in parent- or self-reported ADHD symptoms by calendar birth month. CONCLUSION: Relative immaturity compared to class mates might contribute to ADHD diagnosis and pharmacotherapy despite absence of parallel findings in reported ADHD symptom loads by relative immaturity. Increased clinical awareness of this phenomenon may be warranted to decrease risk for imprecise diagnostics and treatment. We speculate that flexibility regarding age at school start according to individual maturity could reduce developmentally inappropriate demands on children and improve the precision of ADHD diagnostic practice and pharmacological treatment.Swedish Research Council (2010-3184)Karolinska Institutet Center of Neurodevelopmental Disorders (KIND)Accepte

Optimal Hardy Weight for Second-Order Elliptic Operator: An Answer to a Problem of Agmon

For a general subcritical second-order elliptic operator $P$ in a domain $\Omega \subset \mathbb{R}^n$ (or noncompact manifold), we construct Hardy-weight $W$ which is optimal in the following sense. The operator $P - \lambda W$ is subcritical in $\Omega$ for all $\lambda < 1$, null-critical in $\Omega$ for $\lambda = 1$, and supercritical near any neighborhood of infinity in $\Omega$ for any $\lambda > 1$. Moreover, if $P$ is symmetric and $W>0$, then the spectrum and the essential spectrum of $W^{-1}P$ are equal to $[1,\infty)$, and the corresponding Agmon metric is complete. Our method is based on the theory of positive solutions and applies to both symmetric and nonsymmetric operators. The constructed Hardy-weight is given by an explicit simple formula involving two distinct positive solutions of the equation $Pu=0$, the existence of which depends on the subcriticality of $P$ in $\Omega$.Comment: A counterexample to Conjecture 13.

Utveckling av tappar för flödesreglering av järnmalm

Storage and handling of bulk materials in a system of silos and conveyors requires a set-up that can regulate the flow of material, a system used within LKAB is a type of vibratory feeder. These are heavily loaded resulting in continuous wear, shock and vibration. Problems that often arise are fatigue, extensive abrasion as well as bearing-failures and damaged fittings. The aim of this project was to develop the next generation feeder with focus on safety, availability and maintainability. A new design has been developed with respect to these goals and clear improvement opportunities have been presented. Through a needs analysis with study visits as well as examination and operation of the feeder systems, areas of improvement have been identied. A requirement specication has been developed to clarify the target values for the new solution and thus accommodate the needs. The developed solution maintains flow characteristics from existing systems and results in a weight loss of over 1200 kg as well as more efficient maintenance procedures

NO-CODE AI : En kvalitativ utvärdering av ett lättillgängligt AI-verktyg

The development of Information technology has undergone drastic changes in the last decade, and it has changed how organizations work and function. The latest development of IT is Artificial intelligence (AI). Although AI has been researched quite extensively, we are now seeing a new phenomenon taking place within the field of AI,which has not yet been thoroughly studied. This phenomenon is what we call No-Code AI. This refers to tools and systems which provides advanced AI-technology but does not require any vast technological competence to use. In this study we will contribute to this field by looking at how No-Code AI tools changes and affects the value creation process within organizations. To do this, we have conducted a qualitative method in which we combine document analysis and retrospective reflection. We have also performed testing of a tool which can be categorized as a No-code AI tool. Our study showed that no-code AI has great potential to influence how organizations conduct business, but also change how value is created. We also found that when AI becomes more accessible to organizations, it can result in a, so called, democratization of AI. When this democratization takes place, organizations must adopt and change how they operate to remain competitive. Moreover, the factors which were previously important to create value with AI, have changed

Method Development for Road Grip Correlation between Different Force Based Sensors

This thesis presents an experimental approach on how to evaluate the correlation between different force based road grip sensors. Road grip sensors are commonly used to evaluate road safety conditions, eliminating uncertainty for road maintenance. Today, different technologies have been developed to measure the interactions between tire and road to generate a friction value that describes the amount of grip a tire has on the measured surface. Different systems generates different friction values, thus depending on the measurement system, the road maintenance requirement specifications varies. A correlation between the systems is therefore important to enable specification translations for nations in the Nordic region. The Norwegian Public Road Administration, NPRA has three types of systems that use the technology of longitudinal slip to measure the friction value, with a pulse braking measurement tire.While Luleå University of Technology has a different system, RT3 Curve, that use the technology of lateral slip, with two toe in set tires causing a slip-angle, forcing the measurement tires to slide continuously. Tests were executed in Røros, Norway for two days during winter conditions. The objectives were to investigate if there was any correlation between the systems and the main depending factors. The results showed that on compact snow and sand covered roads the NPRA systems measured approximately 70 % of the RT3's measured value.A linear regression showed that 77 % of the NPRA systems variations can be explained by the variations of the RT3 system.The main depending factors are the different measurement tires and the sample-rates. Future studies are necessary to cover more different road surfaces.Validerat; 20160612 (global_studentproject_submitter

NO-CODE AI : En kvalitativ utvärdering av ett lättillgängligt AI-verktyg

The development of Information technology has undergone drastic changes in the last decade, and it has changed how organizations work and function. The latest development of IT is Artificial intelligence (AI). Although AI has been researched quite extensively, we are now seeing a new phenomenon taking place within the field of AI,which has not yet been thoroughly studied. This phenomenon is what we call No-Code AI. This refers to tools and systems which provides advanced AI-technology but does not require any vast technological competence to use. In this study we will contribute to this field by looking at how No-Code AI tools changes and affects the value creation process within organizations. To do this, we have conducted a qualitative method in which we combine document analysis and retrospective reflection. We have also performed testing of a tool which can be categorized as a No-code AI tool. Our study showed that no-code AI has great potential to influence how organizations conduct business, but also change how value is created. We also found that when AI becomes more accessible to organizations, it can result in a, so called, democratization of AI. When this democratization takes place, organizations must adopt and change how they operate to remain competitive. Moreover, the factors which were previously important to create value with AI, have changed

Experimental studies on the role of peat fuel in preventing bed agglomeration during fluidized bed combustion of biomass fuels

Upprättat; 2002; 20080203 (ohmmar

Equestrian surfaces – a guide

Equestrian arena surfaces are a major investment for stable owners, riding clubs and private horse owners. With the growth of equestrian sport in recent decades, both in terms of financial turnover and number of participants, demands on and expectations on equestrian surfaces have increased. Surfaces are expected to promote both performance and soundness. Scientific testing of equine surfaces was first developed within Thoroughbred and Standardbred racing, where for decades scientists have studied associations between orthopaedic injury and surface properties. The background of biomechanical research into equine surfaces is described in more detail in the foreword. Thanks to these studies the information in this guide is supported by scientific data and on-going research. The guide also utilises advice from international arena consultants and equestrian professionals with years of practical experience of building and maintaining surfaces. The guide is aimed at those who want to build or renovate a riding arena, or those who require more knowledge about riding surfaces. Furthermore the guide provides advice on building and maintaining an indoor or outdoor arena. Many equestrians discuss and want an answer to what is ”the best” riding surface. As this guide shows, it is wiser to talk about a ‘surface that is most suited to your and your horse’s needs’, and that how well it works will also depend on how you treat it