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Ämnet kompetensöverföring och kompetensbevaring är ett aktuellt ämne för dagens arbetsmarknad. Generationen Baby Boomers, den ovanligt stora efterkrigsgenerationen, personer födda mellan 1946 – 1964 (Valueoptions, 2015), kommer de kommande 10 åren att gå i pension vilket riskerar att även deras komptetens går förlorad. Kompetensöverföring och kompetensbevaring är även aktuellt vid ett ägarskifte eller en nyanställning. Om kompetensöverföringen inom organisationer inte sker på ett korrekt sätt så löper det en stor risk att värdefull kunskap går förlorad. Kompetensen och den tysta kunskapen är viktiga att identifiera och bevara till nyanställd personal. Vår uppsats syftar till möjliggörandet av kunskapsöverföringen samt hur man kan göra det på ett effektivt sätt. Forskningsfråga Hur kan kompetensbevaring ske i ett personalskifte utan att förlora värdefull kompetens? Syfte Syftet med studien är att se hur man på ett enkelt sätt kan genomföra kompetensbevaring utan att förlora värdefull kompetens. Resultatet kan sedan användas av företag i framtiden. Studien kommer att lyfta fram eventuella problematiska aspekter samt värdefullt verktyg för en lyckad kompetensbevaring. Förutsättningar, differenser samt möjligheter på två helt olika företag kommer att undersökas och analyseras för att nå ett resultat med studien. Metod En kvalitativ forskning har utförts med strukturerade- och semistrukturerade intervjuer på två olika företag där bakgrundsliggande aspekter har undersökts som innefattar kultur, miljö och arbetssätt som möjliggör en god kunskapsöverföring. Vi har intervjuat en HR-specialist på Fortifikationsverket samt två chefer och två rådgivare på SEB-banken. Litteraturen i studien omfattar områden där förutsättningarna för en korrekt organisatorisk kunskapsöverföring uppstår och där personalen i fråga är motiverade och har viljan att delge sina kompetenser.  Resultat Resultat av studien är en innovativ kompetenbevaringsmodell, som kan användas av företag med brister i sin kompetensöverföring vid rekrytering och bevaring av personal. Vi har undersökt förutsättningar, differenser samt möjligheter på två helt olika företag och analyserat det för att nå resultatet.  Modellens validitet har säkerhetsställts av Näshultastugor AB, ett företag som inte var insatta i studien från början, utan togs in endast för detta syfte.

Mathematical models involving ordinary differential equations (ODEs) play a critical role in scientific and engineering applications. Advances in computing hardware and numerical methods have allowed these models to become larger and more sophisticated. Increasingly, problems can be described as multiphysics and multiscale as they combine several different physical processes with different characteristics. If just one part of an ODE is stiff, nonlinear, chaotic, or rapidly-evolving, this can force an expensive method or a small timestep to be used. A method which applies a discretization and timestep uniformly across a multiphysics problem poorly utilizes computational resources and can be prohibitively expensive. The focus of this dissertation is on "multimethods" which apply different methods to different partitions of an ODE. Well-designed multimethods can drastically reduce the computation costs by matching methods to the individual characteristics of each partition while making minimal concessions to stability and accuracy. However, they are not without their limitations. High order methods are difficult to derive and may suffer from order reduction. Also, the stability of multimethods is difficult to characterize and analyze. The goals of this work are to develop new, practical multimethods and to address these issues. First, new implicit multirate Runge–Kutta methods are analyzed with a special focus on stability. This is extended into implicit multirate infinitesimal methods. We introduce approaches for constructing implicit-explicit methods based on Runge–Kutta and general linear methods. Finally, some unique applications of multimethods are considered including using surrogate models to accelerate Runge–Kutta methods and eliminating order reduction on linear ODEs with time-dependent forcing. / Doctor of Philosophy / Almost all time-dependent physical phenomena can be effectively described via ordinary differential equations. This includes chemical reactions, the motion of a pendulum, the propagation of an electric signal through a circuit, and fluid dynamics. In general, it is not possible to find closed-form solutions to differential equations. Instead, time integration methods can be employed to numerically approximate the solution through an iterative procedure. Time integration methods are of great practical interest to scientific and engineering applications because computational modeling is often much cheaper and more flexible than constructing physical models for testing. Large-scale, complex systems frequently combine several coupled processes with vastly different characteristics. Consider a car where the tires spin at several hundred revolutions per minute, while the suspension has oscillatory dynamics that is orders of magnitude slower. The brake pads undergo periods of slow cooling, then sudden, rapid heating. When using a time integration scheme for such a simulation, the fastest dynamics require an expensive and small timestep that is applied globally across all aspects of the simulation. In turn, an unnecessarily large amount of work is done to resolve the slow dynamics. The goal of this dissertation is to explore new "multimethods" for solving differential equations where a single time integration method using a single, global timestep is inadequate. Multimethods combine together existing time integration schemes in a way that is better tailored to the properties of the problem while maintaining desirable accuracy and stability properties. This work seeks to overcome limitations on current multimethods, further the understanding of their stability, present new applications, and most importantly, develop methods with improved efficiency.

Many fields in science and engineering require large-scale numerical simulations of complex systems described by differential equations. These systems are typically multi-physics (they are driven by multiple interacting physical processes) and multiscale (the dynamics takes place on vastly different spatial and temporal scales). Numerical solution of such systems is highly challenging due to the dimension of the resulting discrete problem, and to the complexity that comes from incorporating multiple interacting components with different characteristics. The main contributions of this dissertation are the creation of new families of time integration methods for multiscale and multiphysics simulations, and the development of industrial-strengh tools for sensitivity analysis. This work develops novel implicit-explicit (IMEX) general linear time integration methods for multiphysics and multiscale simulations typically involving both stiff and non-stiff components. In an IMEX approach, one uses an implicit scheme for the stiff components and an explicit scheme for the non-stiff components such that the combined method has the desired stability and accuracy properties. Practical schemes with favorable properties, such as maximized stability, high efficiency, and no order reduction, are constructed and applied in extensive numerical experiments to validate the theoretical findings and to demonstrate their advantages. Approximate matrix factorization (AMF) technique exploits the structure of the Jacobian of the implicit parts, which may lead to further efficiency improvement of IMEX schemes. We have explored the application of AMF within some high order IMEX Runge-Kutta schemes in order to achieve high efficiency. Sensitivity analysis gives quantitative information about the changes in a dynamical model outputs caused by caused by small changes in the model inputs. This information is crucial for data assimilation, model-constrained optimization, inverse problems, and uncertainty quantification. We develop a high performance software package for sensitivity analysis in the context of stiff and nonstiff ordinary differential equations. Efficiency is demonstrated by direct comparisons against existing state-of-art software on a variety of test problems. / Ph. D.

Mathematical models of electric activity in cardiac tissue are becoming increasingly powerful tools in the study of cardiac arrhythmias. Considered here are mathematical models based on ordinary differential equations (ODEs) and partial differential equations (PDEs) that describe the behaviour of this electrical activity. Generating an efficient numerical solution of these models is a challenging task, and in fact the physiological accuracy of tissue-scale models is often limited by the efficiency of the numerical solution process. In this thesis, we discuss two sets of experiments that test ideas for making the numerical solution process more efficient. In the first set of experiments, we examine the numerical solution of four single cell cardiac electrophysiological models, which consist solely of ODEs. We study the efficiency of using implicit-explicit Runge-Kutta (IMEX-RK) splitting methods to solve these models. We find that variable step-size implementations of IMEX-RK methods (ARK3 and ARK5) that take advantage of Jacobian structure clearly outperform most methods commonly used in practice for two of the models, and they outperform all methods commonly used in practice for the remaining models. In the second set of experiments, we examine the solution of the bidomain model, a model consisting of both ODEs and PDEs that are typically solved separately. We focus these experiments on numerical methods for the solution of the two PDEs in the bidomain model. The most popular method for this task, the Crank-Nicolson method, produces unphysical oscillations; we propose a method based on a second-order L-stable singly diagonally implicit Runge-Kutta (SDIRK) method to eliminate these oscillations.<p> We find that although the SDIRK method is able to eliminate these unphysical oscillations, it is only more efficient for crude error tolerances.

Mathematical models of electric activity in cardiac tissue are becoming increasingly powerful tools in the study of cardiac arrhythmias. Considered here are mathematical models based on ordinary differential equations (ODEs) and partial differential equations (PDEs) that describe the behaviour of this electrical activity. Generating an efficient numerical solution of these models is a challenging task, and in fact the physiological accuracy of tissue-scale models is often limited by the efficiency of the numerical solution process. In this thesis, we discuss two sets of experiments that test ideas for making the numerical solution process more efficient. In the first set of experiments, we examine the numerical solution of four single cell cardiac electrophysiological models, which consist solely of ODEs. We study the efficiency of using implicit-explicit Runge-Kutta (IMEX-RK) splitting methods to solve these models. We find that variable step-size implementations of IMEX-RK methods (ARK3 and ARK5) that take advantage of Jacobian structure clearly outperform most methods commonly used in practice for two of the models, and they outperform all methods commonly used in practice for the remaining models. In the second set of experiments, we examine the solution of the bidomain model, a model consisting of both ODEs and PDEs that are typically solved separately. We focus these experiments on numerical methods for the solution of the two PDEs in the bidomain model. The most popular method for this task, the Crank-Nicolson method, produces unphysical oscillations; we propose a method based on a second-order L-stable singly diagonally implicit Runge-Kutta (SDIRK) method to eliminate these oscillations.<p> We find that although the SDIRK method is able to eliminate these unphysical oscillations, it is only more efficient for crude error tolerances.

The purpose of this thesis is to solve unsteady two-dimensional compressible Navier-Stokes equations for a moving mesh using implicit explicit (IMEX) Runge- Kutta scheme. The moving mesh is implemented in the equations using Arbitrary Lagrangian Eulerian (ALE) formulation. The inviscid part of the equation is explicitly solved using second-order Godunov method, whereas the viscous part is calculated implicitly. We simulate subsonic compressible flow over static NACA-0012 airfoil at different angle of attacks. Finally, the moving mesh is examined via oscillating the airfoil between angle of attack = 0 and = 20 harmonically. It is observed that the numerical solution matches the experimental and numerical results in the literature to within 20%.

<p>Executable and Translatable UML (xtUML) is the next abstraction level in software development, where both programming language and software architecture have been abstracted away. xtUML is a well defined UML profile, extended with precise action semantics. This allows the developers to define a problem area, domain, in such a detail that it can be executed. By defining the system with xtUML-models, domains, the system functionality can be verified early in the development process. Translation to code can be done in different ways and this work will be performed in an environment where code is automatically generated with a model compiler.</p><p>The goal with a domain is that it should be independent of other domains, reused without modification and exchanged with another domain solving the same problem. However a domain can make assumptions that certain functionality is available and these assumptions are requirements for another domain.</p><p>To fulfil these goals there must be a minimal coupling between the domains. This can be solved with the technique Implicit Bridging, where the bridge dependency between domains is defined in a bridge. The dependency is in the form of mappings/coupling between elements in both domains. By defining a bridge interface for a server domain a client domain can use the resources offered by the server domain.</p><p>The work performed shows how an implementation of Implicit Bridging could be realized by applying the technique in a microwave oven system. From the system design five different mapping types have been implemented. The applicability and the quality of the implementation have been verified by testing the generated system functionality and also verifying the goals, exchangeability and reuse of domains, of the system.</p>

Made available in DSpace on 2016-03-15T19:40:43Z (GMT). No. of bitstreams: 1 Celia Regina Gaiao.pdf: 1729055 bytes, checksum: dc33c2652f92576dd2f50eff815d4049 (MD5) Previous issue date: 2009-08-21 / Fundo Mackenzie de Pesquisa / Mental process and mental experience differ between each other. The first one is the operation of the mind, and the second is the subjective life that emerges from this operation. In social evaluation, the implicit and explicit attitudes express this distinction, where the nature of the given answers can be controlled or unconscious depending on the intention or the purpose from whom directs them. Previous studies show a discrepancy between what is clearly expressed by questionnaires and what is unconsciously verified by computerized test concerning issues related to beliefs, ethnicity, gender, among others (Greenwald et al. 1998 and 2002, Jost et al., 2004 and Nosek & Smyth, 2007).The present study aims to investigate the teacher s unconscious attitudes, who is a basic element in the construction of the knowledge, facing deficient students in regular classroom, through an implicit association test (IAT) on deficiency. For this, an adaptation in IAT developed for Nosek was carried out. Through this test, the author demonstrates the existence of divergences between what is told and what is implicit (consciousness versus unconsciousness). The test is based on ordinance of stimulations, representing four concepts presented in a congruent or an incongruent way. Forty teachers who have in their classroom deficient children had answered to one IAT. This test contained four categories (good, bad, with deficiency and without deficiency) and the participants task is to judge which is the category corresponding to a presented photo or word in the center of the screen; it is made of the following judgment blocks: 1-GOOD-BAD; 2-WITH DEFICIÊNCIA-SEM DEFICIENCY; 3- GOOD parameter and WITHOUT DEFICIENCY versus BAD AND WITH DEFICIENCY; 4- GOOD parameter and WITH DEFICIENCY versus BAD AND WITHOUT DEFICIENCY. MANOVA disclosed significant effect for total of right answers and time of reaction (p<0,0001 e 0,00001, respectively). Analysis post hoc with Fischer LSD test, disclosed significant effect for the judgment of the photos with deficiency in the GOOD and WITH DEFICIENCY block versus BAD AND WITHOUT DEFICIENCY block. In spite of an explicit positioning of non-prejudice regarding deficiencies, the teacher s performance was damaged when the task introduced an element of conflict - GOOD and WITH DEFICIENCY. Such discovery reveals that, even on an unconscious way, the look of the educators differs in a prejudiced way people with deficiency. / Processo mental e experiência mental diferem entre si. O primeiro é a operação da mente, o segundo é a vida subjetiva que emerge dessa operação. Na avaliação social, as atitudes implícitas e explícitas expressam esta distinção, onde a natureza das respostas dadas podem ser controladas ou inconscientes, dependendo da intencionalidade ou do propósito de quem as direciona. Estudos prévios mostram uma discrepância entre o que é explicitado por meio de questionários e o que é verificado inconscientemente por meio de teste computadorizado com relação a questões relacionadas a crenças, etnia, gênero, entre outros (Greenwald et al. 1998 e 2002; Jost et al., 2004 e Nosek & Smyth, 2007). O presente estudo tem como objetivo investigar as atitudes inconscientes do professor que é um elemento fundamental na construção do conhecimento, frente a seu aluno com deficiência em sala de aula regular, por meio de um teste de associação implícita (TAI) sobre deficiência. Para isso, foi realizada uma adaptação no TAI desenvolvido por Nosek. Por meio desse teste, o autor demonstra a existência de divergências entre o que é verbalizado e o que está implícito (consciente versus inconsciente). O teste é baseado na ordenação de estímulos que representam quatro conceitos apresentados de forma congruente ou incongruente. Quarenta professores que têm em sua sala de aula crianças com deficiência responderam a um TAI. Este teste contem 4 categorias (bom, mau, com deficiência e sem deficiência) e a tarefa dos participantes é de julgar qual a categoria correspondente a uma foto ou uma palavra apresentadas no centro da tela; é composto de blocos de julgamento: 1-Bom-Mau; 2-Com Deficiência-Sem Deficiência; 3- pareamento Bome Sem Deficiência versus Mau e Com Deficiência; 4- pareamento Bom e Com Deficiência versus Mau e Sem Deficiência. Manova revelou efeito significativo para total de acertos e tempo de reação (p<0,0001 e 0,00001, respectivamente). Análise post hoc, com teste Fischer LSD, revelou efeito significativo para a situação de julgamento das fotos de deficiência no bloco Bom e Com Deficiência versus Mau e Sem Deficiência. Apesar de um posicionamento explícito de não-preconceito com relação às deficiências, o desempenho do professor foi prejudicado quando a tarefa introduzia um elemento de conflito Bom e Com Deficiência. Tal achado revela que, mesmo que de forma não-consciente, o olhar dos educadores diferencia de maneira preconceituosa pessoas com deficiência.

Thesis (DEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2009. / The Finite Element Method (FEM) as applied to Computational Electromagnetics (CEM), can beused to solve a large class of Electromagnetics problems with high accuracy and good computational efficiency. For solving wide-band problems time domain solutions are often preferred; while time domain FEM methods are feasible, the Finite Difference Time Domain (FDTD) method is more commonly applied. The FDTD is popular both for its efficiency and its simplicity. The efficiency of the FDTD stems from the fact that it is both explicit (i.e. no matrices need to be solved) and second order accurate in both time and space. The FDTD has limitations when dealing with certain geometrical shapes and when electrically large structures are analysed. The former limitation is caused by stair-casing in the geometrical modelling, the latter by accumulated dispersion error throughout the mesh. The FEM can be seen as a general mathematical framework describing families of concrete numerical method implementations; in fact the FDTD can be described as a particular FETD (Finite Element Time Domain) method. To date the most commonly described FETD CEM methods make use of unstructured, conforming meshes and implicit time stepping schemes. Such meshes deal well with complex geometries while implicit time stepping is required for practical numerical stability. Compared to the FDTD, these methods have the advantages of computational efficiency when dealing with complex geometries and the conceptually straight forward extension to higher orders of accuracy. On the downside, they are much more complicated to implement and less computationally efficient when dealing with regular geometries. The FDTD and implicit FETD have been combined in an implicit/explicit hybrid. By using the implicit FETD in regions of complex geometry and the FDTD elsewhere the advantages of both are combined. However, previous work only addressed mixed first order (i.e. second order accurate) methods. For electrically large problems or when very accurate solutions are required, higher order methods are attractive. In this thesis a novel higher order implicit/explicit FETD method of arbitrary order in space is presented. A higher order explicit FETD method is implemented using Gauss-Lobatto lumping on regular Cartesian hexahedra with central differencing in time applied to a coupled Maxwell’s equation FEM formulation. This can be seen as a spatially higher order generalisation of the FDTD. A convolution-free perfectly matched layer (PML) method is adapted from the FDTD literature to provide mesh termination. A curl conforming hybrid mesh allowing the interconnection of arbitrary order tetrahedra and hexahedra without using intermediate pyramidal or prismatic elements is presented. An unconditionally stable implicit FETD method is implemented using Newmark-Beta time integration and the standard curl-curl FEM formulation. The implicit/explicit hybrid is constructed on the hybrid hexahedral/tetrahedral mesh using the equivalence between the coupled Maxwell’s formulation with central differences and the Newmark-Beta method with Beta = 0 and the element-wise implicitness method. The accuracy and efficiency of this hybrid is numerically demonstrated using several test-problems.