Aged embankment imaging and assessment using surface waves

Rapid, non-intrusive surface wave surveys provide depth profiles from which ground models can be generated for use in earthwork condition assessment. Stiffness throughout earthworks controls the behaviour under static and dynamic loads, and characterising heterogeneity is of interest in relation to the stability of engineered backfill and life-cycle deterioration in aged utility and transportation infrastructure. Continuous surface wave methods were used to identify interfaces between fine- and coarse-grained fill in an end-tipped embankment along the Great Central Railway in Nottinghamshire, UK. Multichannel analysis of surface wave (MASW) methods were used to characterise subsurface voiding in a canal embankment along the Knottingley and Goole canal near Eggborough, Yorkshire. MASW methods are currently being used to study extreme weather impacts on the stability of a highplasticity clay embankment along the Gloucestershire–Warwickshire railway near Laverton. Optimal results were obtained using equipment capable of generating and detecting over wide frequency ranges.

The microphysics of collisionless shock waves

Collisionless shocks, that is shocks mediated by electromagnetic processes, are customary in space physics and in astrophysics. They are to be found in a great variety of objects and environments: magnetospheric and heliospheric shocks, supernova remnants, pulsar winds and their nebulæ, active galactic nuclei, gamma-ray bursts and clusters of galaxies shock waves. Collisionless shock microphysics enters at different stages of shock formation, shock dynamics and particle energization and/or acceleration. It turns out that the shock phenomenon is a multi-scale non-linear problem in time and space. It is complexified by the impact due to high-energy cosmic rays in astrophysical environments. This review adresses the physics of shock formation, shock dynamics and particle acceleration based on a close examination of available multi-wavelength or in situ observations, analytical and numerical developments. A particular emphasis is made on the different instabilities triggered during the shock formation and in association with particle acceleration processes with regards to the properties of the background upstream medium. It appears that among the most important parameters the background magnetic field through the magnetization and its obliquity is the dominant one. The shock velocity that can reach relativistic speeds has also a strong impact over the development of the micro-instabilities and the fate of particle acceleration. Recent developments of laboratory shock experiments has started to bring some new insights in the physics of space plasma and astrophysical shock waves. A special section is dedicated to new laser plasma experiments probing shock physics.

Hur ett tvärfunktionellt samarbete kan motverka stuprörsstrukturer : Kommunikationens roll i det organisatoriska gränssnittet mellan olika avdelningar

Stovepipes, or also called silos, appear in many different organizations and sectors and contribute to problems when employees or managers tend to look more to their own, or the individual departments, objectives rather than to the organizations. The purpose of this study was to identify different communicative factors that promote stovepipes in order to further identify the most critical factor to disarm. A case study has been done at a selected company, with a stovepipe structure, in order to achieve the purpose of the study. The case study has included interviews and observations to identify different problem areas which then have been compared with three communicative factors identified in previous studies. The factor that had the most connections to the problem areas have been considered the most critical factor. The result of the study indicates that “A lack of understanding each other's work” is the most critical factor in stovepipe structures and that it can be prevented by following five recommendations: bring up positive collaboration continually, raise problems with each other instead of with others, identify different communication paths in and between the departments, implement a long-term model for preventing stovepipes and set up workshops between the involved departments. The conclusion of the study is that stovepipes create several undesirable effects in the organization but that the efforts to counter these problems do not have to be complicated. Following five small steps into a better collaboration and communication can be enough to be on your way to a better organizational structure.

”Få in världen i klassrummet” : En studie om skönlitteraturens roll i gymnasieskolans SVAundervisning

Uppsatsens övergripande syfte är att åskådliggöra hur några gymnasielärare behöriga i svenska som andraspråk respektive svenska betraktar skönlitteraturens roll i ämnet svenska som andraspråk (SVA) och hur det praktiska klassrumsarbetet med litteraturundervisning ser ut. I uppsatsen diskuteras även lärarnas syn på skönlitteraturen i SVA-ämnet i jämförelse med i svenskämnet i relation ämnes- och kursplanerna i Läroplan, examensmål och gymnasiegemensamma ämnen för gymnasieskola 2011. För att uppnå syftet och besvara frågeställningarna har jag genomfört en kvalitativ studie där fyra lärare intervjuats, samtliga verksamma på nationella program. Av resultaten framkommer att lärarna starkt betonar skönlitteraturens betydelse i SVA-undervisningen. De viktigaste motiven för skönlitteraturen som lyfts fram är språkutveckling, identitetsutveckling, främjande av empatisk och demokratisk förmåga samt som förmedlare av svenska referensramar. Vid valen av litterära texter beaktar lärarna styrdokumentens skrivningar samt språkliga faktorer. Två arbetssätt som framhålls är boksamtal och tematiskt arbete. Det litterära samtalet framhävs som positivt för lärandet liksom läsande i en större kontext inom ett gemensamt tema. Lärarna understryker att skillnaderna i styrdokumenten mellan svenskämnena är alltför stora vad avser skrivningar om skönlitteratur och de anser att SVA borde likna svenskämnet mera vad gäller det litterära ämnesinnehållet.

Begreppens roll vid inlärning av algebra : En litteraturstudie om den roll begrepp och begreppsförmåga spelar vid inlärning av algebra för elever i årskurs 4-6

Svenska elever har presterat dåligt i internationella undersökningar en längre tid när det gäller algebraområdet i matematik. Elevernas begreppsförståelse har pekats ut som en faktor som spelar in i de dåliga resultaten för svenska elever del. Syftet med denna studie har därför varit att ta reda på den roll som begrepp och begreppsförmåga spelar vid inlärning av algebra samt vilken begreppsförståelse elever i årskurs 4-6 har. Genom en systematisk litteraturstudie har frågeställningarna besvarats. Resultaten visar att brister i begreppsförståelse i algebra också leder till brister i kunskap i algebra. Undervisning med fokus på begrepp leder till bättre förståelse för begrepp samtidigt som det även leder till procedurell kunskap. Elever i årskurs 4-6 kan hantera variabler och använda dem i matematiska uttryck. Fördelar med en tidig introduktion av variabelbegreppet är att elever bygger en bättre förståelse för begreppet.

Begreppens roll vid inlärning av algebra : En litteraturstudie om den roll begrepp och begreppsförmåga spelar vid inlärning av algebra för elever i årskurs 4-6

Svenska elever har presterat dåligt i internationella undersökningar en längre tid när det gäller algebraområdet i matematik. Elevernas begreppsförståelse har pekats ut som en faktor som spelar in i de dåliga resultaten för svenska elever del. Syftet med denna studie har därför varit att ta reda på den roll som begrepp och begreppsförmåga spelar vid inlärning av algebra samt vilken begreppsförståelse elever i årskurs 4-6 har. Genom en systematisk litteraturstudie har frågeställningarna besvarats. Resultaten visar att brister i begreppsförståelse i algebra också leder till brister i kunskap i algebra. Undervisning med fokus på begrepp leder till bättre förståelse för begrepp samtidigt som det även leder till procedurell kunskap. Elever i årskurs 4-6 kan hantera variabler och använda dem i matematiska uttryck. Fördelar med en tidig introduktion av variabelbegreppet är att elever bygger en bättre förståelse för begreppet.

Initiation of Orderly Spinning Detonation Waves via Phased Sparking

Thesis (Master's)--University of Washington, 2016-06

Finite Element Modeling of Spiral Frequency Steerable Acoustic Transducers (FSATs) for guided waves based Structural Health Monitoring of plate-like structures

Structural Health Monitoring (SHM) is an emerging area of research associated to improvement of maintainability and the safety of aerospace, civil and mechanical infrastructures by means of monitoring and damage detection. Guided wave structural testing method is an approach for health monitoring of plate-like structures using smart material piezoelectric transducers. Among many kinds of transducers, the ones that have beam steering feature can perform more accurate surface interrogation. A frequency steerable acoustic transducer (FSATs) is capable of beam steering by varying the input frequency and consequently can detect and localize damage in structures. Guided wave inspection is typically performed through phased arrays which feature a large number of piezoelectric transducers, complexity and limitations. To overcome the weight penalty, the complex circuity and maintenance concern associated with wiring a large number of transducers, new FSATs are proposed that present inherent directional capabilities when generating and sensing elastic waves. The first generation of Spiral FSAT has two main limitations. First, waves are excited or sensed in one direction and in the opposite one (180 ̊ ambiguity) and second, just a relatively rude approximation of the desired directivity has been attained. Second generation of Spiral FSAT is proposed to overcome the first generation limitations. The importance of simulation tools becomes higher when a new idea is proposed and starts to be developed. The shaped transducer concept, especially the second generation of spiral FSAT is a novel idea in guided waves based of Structural Health Monitoring systems, hence finding a simulation tool is a necessity to develop various design aspects of this innovative transducer. In this work, the numerical simulation of the 1st and 2nd generations of Spiral FSAT has been conducted to prove the directional capability of excited guided waves through a plate-like structure.

Large-scale Roll Out of Online Prospective Measurement of Mood Symptoms in Affective Disorders

Background and Aims: True Colours is an online prospective mood-monitoring system developed at the University of Oxford to assist local patients and clinicians with monitoring course of illness in bipolar disorder. We report our initial experiences of using True Colours for research purposes in the Bipolar Disorder Research Network (BDRN; www.bdrn.org), a large research network of individuals with mood disorders spread throughout the UK. Methods: After initial piloting to ensure the practicality/acceptability of using True Colours within BDRN, we invited all BDRN participants (n = 7000) to participate in weekly True Colours ratings via three postal invitations sent over an 8-month period. Results: Following the three postal invitations, 915 individuals have so far expressed an interest in joining True Colours, and, of these, 662 (72.3%) have registered. 32 of those who registered for True Colours (5%) have so far asked to leave the system. Positive feedback from participants has focused around the ease of use and convenience of True Colours and potential clinical utility of the graphical representation of weekly mood scores. Conclusions: We have demonstrated that large-scale prospective mood monitoring for research purposes using a contemporary online approach is feasible. Challenges have included: (i) variation in participants’ technological ability; (ii) management of requests for clinical advice based on mood scores within a research setting; and, (iii) resources required to provide access and on-going support for participants using True Colours. We continue to expand recruitment to True Colours within BDRN, and plan to trial email invitations in the next phase of recruitment.

Samhällskunskap och historia i svensk gymnasieskola: ämnenas roll och relation i diskurs och ämnesplaner

The adoption of new syllabuses in history and social science in the new Swedish curriculum raises questions on the relationship between the two subjects. Social Science and History as school subjects have previously been described as both competing and complementary. The competing aspect has mainly been descibed in terms of citizenship education and the complementary aspect has been described in terms of content, abilities, and temporality. This article discusses how history and social science relate to these four topics in didactic discourse and in the new syllabuses. In the didactic discource both subjects underline the importance of making subject matter useful in life outside school. However, the new syllabuses are very differently formulated in this sense. History is closely connected to citizenship education and describes content, abilities and temporality in such a context. Social Science on the other hand downtunes the traditional role as a subject important for citizenship. Instead, focus is aimed at disciplinary thinking and using knowledge to understand social science methods and theories. This development is seen as very problematic and challenging for a meaningful teaching of Social Science in upper secondary school. In response to this challenge, the author proposes interdisciplinary didactic development, especially in developing "dynamic concepts" within Social Science didactics.

Receptors, sparks and waves in a fire-diffuse-fire framework for calcium release

Calcium ions are an important second messenger in living cells. Indeed calcium signals in the form of waves have been the subject of much recent experimental interest. It is now well established that these waves are composed of elementary stochastic release events (calcium puffs or sparks) from spatially localised calcium stores. The aim of this paper is to analyse how the stochastic nature of individual receptors within these stores combines to create stochastic behaviour on long timescales that may ultimately lead to waves of activity in a spatially extended cell model. Techniques from asymptotic analysis and stochastic phase-plane analysis are used to show that a large cluster of receptor channels leads to a release probability with a sigmoidal dependence on calcium density. This release probability is incorporated into a computationally inexpensive model of calcium release based upon a stochastic generalization of the Fire-Diffuse-Fire (FDF) threshold model. Numerical simulations of the model in one and two dimensions (with stores arranged on both regular and disordered lattices) illustrate that stochastic calcium release leads to the spontaneous production of calcium sparks that may merge to form saltatory waves. Illustrations of spreading circular waves, spirals and more irregular waves are presented. Furthermore, receptor noise is shown to generate a form of array enhanced coherence resonance whereby all calcium stores release periodically and simultaneously.