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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

pm3-revision : En välgrundad metodutveckling av metod för revision av förvaltningsstyrning / pm3-auditing : A well grounded developement of an auditing method for Maintenance Management methodology

Larsson, Björn, Jonsson, Zandra January 2013 (has links)
In the field of maintenance management there are but a few models an organization can use. The one model that has risen to the status of being the de facto standard in Sweden is pm3(på maintenance management model). The aim of this study is to lay the groundwork for a new method of evaluate the use of pm3within organizations. Today there is no uniform way of performing such an evaluation, which is necessary in order to diagnose the performance of the systems maintenance organizations.In the process of creating our own method for performing this kind of pm3audit, we further developed the ideas from a study by Lagsten & Nordström (2013) that was performed at the county Region Skåne. The authors of that study had developed ideas about using method rationale as a basis of creating a method for pm3auditing. The usage of method rationale in this fashion gives a higher grade of transparency and insight into the values that are of high importance for successful pm3usage. Our goal in this study has been to develop these ideas into a basis for which the development of a method for pm3auditing, which we want to be practical and efficient.The subject of this study has been the Swedish Tax Agency, where we have studied two maintenance organizations. Our experiences from this have laid the groundwork for how we have developed our visions of a future method for pm3auditing. The theoretical groundwork we have thus laid places great importance on the proper use of narrative interviews. We have also developed practical guidelines for how usage of our pm3auditing method is to be used. / Inom förvaltningsstyrning så finns det ett fåtal olika förvaltningsmodeller, den modell som har blivit de facto standard i Sverige är pm3(på maintenance management model). Denna uppsats har som syfte att lägga grunden för en metod för att utvärdera användningen av pm3hos organisationer, vilken vi kallar pm3-revision. Idag finns det inget enhetligt sätt för organisationer att utföra en sådan utvärdering, vilket är nödvändigt för att kunna ställa diagnos på hur väl förvaltningsorganisationerna fungerar. I skapandet av vår metod för pm3-revision så har vi utgått ifrån en studie av Lagsten & Nordström (2013) som genomfördes hos Region Skåne. De utvecklade vid studien hos Region Skåne idéer om att skapa en revisionsmetod med en grund i begreppet metodrationalitet. Användningen av metodrationalitet ger en ökad tydlighet i vad som är de värderingar som är av hög vikt för framgångsrikt pm3-arbete. Vi har haft som mål att utveckla dessa idéer till en utgångspunkt för utveckling av en metod för pm3-revision, vilken vi vill ska vara praktiskt användbar och verksam.Denna utveckling har åstadkommits med hjälp av en kvalitativ fallstudie hos två förvaltningsobjekt hos Skatteverket. Erfarenheterna från denna studie har legat till grund för hur vi format vårauppfattningar om en framtida metod för pm3-revision. Den utgångspunkt vi formulerat har tagit fasta på bland annat vikten av narrativa intervjuer som datainsamlingsmetod, samt utformat konkreta riktlinjer för genomförandet.
2

IT- och förvaltningsstyrning : En fallstudie om Sveriges mest använda förvaltningsstyrningmodell pm3

Jonsson, Nathalie, Rydstedt, Matilda January 2016 (has links)
The purpose of this study is to provide recommendations to further develop and improvements of models which can be applied to IT governance models for system maintenance. The work investigates gaps in the implementation and using phase of the model pm3 and also models which are inspired in pm3. The aim of the present paper is to answer the research questions which are related to (1) which critical success factors that have an impact on the governance of system maintenance management and also for the model pm3 and (2) how maintenance management models can further be developed and improved. This qualitative study is a case study in which a questionnaire and interview in two steps have been completed. The sample of respondents have been made with a specific purpose that reflects the selected qualities and relevance of the study and also with a geographical distribution. The study resulted in a number of critical success factors for the model pm3 where some of these can be considered as general for all maintenance management models. The results shows the need of a maintenance management model that is designed for the agile working method and suitable for all types and sizes of organisations. It is an area where maintenance management models and pm3  need to develop within. / Syftet med denna studie är att kunna ge rekommendationer till utveckling och förbättringar av modeller som kan tillämpas vid IT-styrning av modeller för systemförvaltning. Arbetet undersöker brister i införandet och användandet av modellen pm3 samt modeller som är inspirerade av pm3. Studiens mål är att besvara frågeställningarna som behandlar (1) vilka kritiska framgångsfaktorer som har en påverkan för styrning av systemförvaltning samt för modellen pm3 och (2) hur förvaltningsstyrningsmodeller och pm3 kan utvecklas och förbättras. Den kvalitativa studien är en fallstudie där en enkätundersökning och två olika intervjusteg har utförts. Urvalet av respondenter har gjorts med ett specifikt syfte som speglar de utvaldas kvaliteter och relevans för studien samt med en geografisk spridning. Studien resulterade i en mängd kritiska framgångsfaktorer för modellen pm3 där en del av dessa kan anses som generella för alla förvaltningsstyrningsmodeller. Resultatet påvisar även behovet av en förvaltningsstyrningsmodell som är anpassad för det agila arbetssättet samt behovet av en modell anpassad för olika storlekar av organisationer. Vilket är ett område som förvaltningsstyrningsmodeller och pm3 bör utvecklas inom.
3

Estudo te?rico aplicado ao petr?leo: estabilidade dos alcenos e recupera??o terci?ria

Freitas, Gutto Raffayson Silva de 22 February 2013 (has links)
Made available in DSpace on 2014-12-17T15:42:05Z (GMT). No. of bitstreams: 1 GuttoRSF_DISSERT.pdf: 5697314 bytes, checksum: 6d49e92c8978493580da74eee2885a8f (MD5) Previous issue date: 2013-02-22 / The present work aims to study the theoretical level of some processes employed in the refining of petroleum fractions and tertiary recovery of this fluid. In the third chapter, we investigate a method of hydrogenation of oil fractions by QTAIM (Quantum Theory of Atoms in Molecules) and thermodynamic parameters. The study of hydrogenation reactions, and the stability of the products formed, is directly related to product improvement in the petrochemical refining. In the fourth chapter, we study the theoretical level of intermolecular interactions that occur in the process of tertiary oil recovery, or competitive interactions involving molecules of non-ionic surfactants, oil and quartz rock where oil is accumulated. Calculations were developed using the semiempirical PM3 method (Parametric Model 3). We studied a set of ten non-ionic surfactants, natural and synthetic origin. The study of rock-surfactant interactions was performed on the surface of the quartz (001) completely hydroxylated. Results were obtained energetic and geometric orientations of various surfactants on quartz. QTAIM was obtained through the analysis of the electron density of interactions, and thus, providing details about the formation of hydrogen bonds and hydrogen-hydrogen systems studied. The results show that the adsorption of ethoxylated surfactants in the rock surface occurs through the hydrogen bonding of the type CH---O, and surfactants derivatives of polyols occurs by OH---O bonds. For structures adsorption studied, the large distance of the surfactant to the surface together with the low values of charge density, indicate that there is a very low interaction, characterizing physical adsorption in all surfactants studied. We demonstrated that surfactants with polar group comprising oxyethylene units, showed the lowest adsorption onto the surface of quartz, unlike the derivatives of polyols / O presente trabalho tem como objetivo o estudo a n?vel te?rico de alguns processos empregados no refino das fra??es do petr?leo e na recupera??o terci?ria deste fluido. No terceiro capitulo, investigamos um m?todo de hidrogena??o das fra??es de petr?leo atrav?s da QTAIM (Quantum Theory of Atoms in Molecules) e par?metros termodin?micos. O estudo das rea??es de hidrogena??o, bem como a estabilidade dos produtos formados, est? diretamente relacionada ? melhoria dos produtos de refino na ind?stria petroqu?mica. No quarto cap?tulo, realizamos o estudo a n?vel te?rico das intera??es intermoleculares que ocorrem no processo de recupera??o terci?ria de petr?leo, ou seja, as intera??es competitivas envolvendo mol?culas de tensoativos n?oi?nicos, o petr?leo e o quartzo da rocha onde o petr?leo est? acumulado. Os c?lculos foram desenvolvidos utilizando o m?todo semi-emp?rico PM3 (Parametric Model 3). Estudamos um conjunto de dez tensoativos n?o-ionicos, de origem natural e sint?ticos. O estudo das intera??es rocha-tensoativo foi realizado sobre a superf?cie do quartzo (001) completamente hidroxilada. Foram obtidos resultados energ?ticos e geom?tricos de v?rias orienta??es dos tensoativos sobre o quartzo. Atrav?s da QTAIM foi obtida a an?lise da densidade eletr?nica das intera??es, e assim, fornecendo detalhes sobre a forma??o de liga??es de hidrog?nio e hidrog?nio-hidrog?nio, nos sistemas estudados. Os resultados obtidos mostram que a adsor??o de tensoativos etoxilados na superf?cie da rocha ocorre atrav?s de liga??o de hidrog?nio do tipo C-H---O, e tensoativos derivados de poli?is ocorre por liga??es O-H---O. Para as estruturas de adsor??o estudadas, a grande dist?ncia do tensoativo para a superf?cie aliada com os baixos valores de densidade de carga, indicam que h? uma intera??o muito fraca, caracterizando uma adsor??o f?sica em todos os tensoativos estudados. Evidenciamos que tensoativos com o grupo polar constitu?do por unidades oxietileno, apresentaram a menor adsor??o sobre a superf?cie do quartzo, ao contr?rio dos derivados de poli?is
4

Estudo estrutural e eletrônico da influência de dopantes em coronenos funcionalizados

Freire, Eduily Benvindo Vaz 18 July 2017 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-01-10T13:05:24Z No. of bitstreams: 1 eduilybenvindovazfreire.pdf: 26345792 bytes, checksum: f56583c0c3a78800d1e94a7d0a63726f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-01-23T11:45:18Z (GMT) No. of bitstreams: 1 eduilybenvindovazfreire.pdf: 26345792 bytes, checksum: f56583c0c3a78800d1e94a7d0a63726f (MD5) / Made available in DSpace on 2018-01-23T11:45:18Z (GMT). No. of bitstreams: 1 eduilybenvindovazfreire.pdf: 26345792 bytes, checksum: f56583c0c3a78800d1e94a7d0a63726f (MD5) Previous issue date: 2017-07-18 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Recentemente, o óxido de grafeno (GO) tornou-se um material de grande interesse físico e tecnológico e não só um material intermediário na síntese de grafeno, mas também como um produto para aplicações diretas. Na tentativa de tornar o GO mais próximo do grafeno, estruturalmente e tecnologicamente falando, o material passa por um processo de redução dos grupos funcionais oxigenados aderidos. Entretanto esse processo de redução não consegue retirar totalmente os grupos funcionais, e a esse material não completamente livre de grupos baseados no oxigênio damos o nome de óxido de grafeno reduzido (rGO). O rGO ao longo dos últimos anos se tornou alvo de pesquisas e muitas aplicações científicas e tec-nológicas como, por exemplo, em dispositivos eletrônicos orgânicos, como diodos emissores de luz (OLEDs), células solares, entre muitos outros. Para tornar este material ainda mais interessante para a área de eletrônica orgânica, propomos a dopagem das nossas moléculas de óxido de grafeno reduzido (rGOm) com átomos de boro, nitrogênio, alumínio silício, fósforo, gálio, germânio e arsênio, um de cada vez e de forma substitutiva. Nosso objetivo e´ fazer com que nosso material se torne um melhor condutor, mantendo ou melhorando sua transparência, pensando no uso deste material como eletrodos em dispositivos orgânicos. Neste trabalho, objetivamos estudar nossas moléculas de óxido de grafeno reduzido (rGOm) nos seus aspectos estruturais e eletrônicos, utilizando métodos semi-empíricos e ab initio a nível DFT, implementados nos programas GAMESS e MOPAC. Usamos como modelos de rGO estruturas contendo 42, 84 e 154 átomos, derivados da molécula de coroneno com adição de três grupos funcionais oxigenados: hidroxil, carboxil e epoxi. Começamos o trabalho fazendo uma busca conformacional da estrutura das nossas rGOm incluindo cada grupo funcional oxigenado ligado aos carbonos dos coronenos. Estudamos as rGOm juntamente com a dopagem, substituindo carbonos na estrutura pelos seguintes átomos: nitrogênio (N), boro (B), fósforo (P), silício (Si), alumínio (Al), arsênio (As), germânio (Ge) e gálio (Ga). Substituímos um átomo da folha de carbono de cada vez. Analisamos o gap de energia entre os estados eletrônicos de fronteira do material, a fim de encontrar tanto o sítio com menor energia total como o sítio com menor valor de gap. Realizamos os cálculos de energia e valor de gap das dopagens mencionadas acima em diferentes níveis de métodos, utilizamos tanto métodos semiempírico (PM3, PM6), quanto DFT (B3LYP, com base 6-31G), fizemos também comparação entre diferentes tipos de aproximação (UHF e RHF) com o objetivo de saber se essas aproximações eram compatíveis entre sícomparando energia total, gap e geometria. Por fim, um dos principais resultados foi a dopagem da rGOm com alumínio. O alumínio quando colocado em alguns sítios específicos promove a aproximação dos orbitais de fronteira, diminuindo o gap, tornando a rGOm do-pado com alumínio um material com propensão a melhor condução elétrica que a rGOm sem dopagem, o que aumenta o interesse na utilização deste material para eletrônica orgânica. / Recently, graphene oxide (GO) has become a material of great physical and technological interest and not only an intermediate material in the synthesis of graphene, but also as a product for direct applications. In an attempt to make GO closer to graphene, structurally and technologically speaking, the material undergoes a process of reduction of adhered oxygenated functional groups. Howe-ver, this reduction process does not completely remove the functional groups, and this material which is not completely free of oxygen-based groups, is called redu-ced graphene oxide (rGO). Over the past few years, RGO has become the target of research and many scientific and technological applications, such as organic electronic devices such as light-emitting diodes (OLEDs), solar cells, and many others. To make this material even more interesting to the area of organic elec-tronics, we propose the doping of our reduced graphene oxide molecules (rGO m) with boron, nitrogen, silicon aluminium, phosphorus, gallium, germanium and arsenic, one at a time and in a substitute way. Our goal is to make our material become a better conductor, maintaining or improving its transparency, thinking of using this material as electrodes in organic devices. In this work, we aim to study our reduced graphene oxide molecules (rGOm) in their structural and electronic aspects, using semi-empirical and ab initio methods at the DFT level, implemented in the GAMESS and MOPAC programs. We used as RGO models structures containing 42, 84 and 154 atoms derived from the coronon molecule with addition of three oxygenated functional groups: hidroxyl, carboxyl and epoxy. We begin the work by making a conformational search of the structure of our rGOm including each oxygenated functional group attached to the carbon atoms of the coronenes. We study the rGOm along with doping, replacing carbons in the structure with the following atoms: nitrogen (N), boron (B), phosphorus (P), silicon (Si), aluminium (Al), arsenic, germanium (Ge) and gallium (Ga). We replace one atom of the carbon sheet each time. We analyzed the energy gap between the border electronic states of the material in order to find both the site with the lowest total energy and the site with the least gap value. We performed the energy calculations and gap value of the above-mentioned dops at different levels of methods, we used both semi-empirical methods (PM3, PM6) and DFT (B3LYP, based on 6-31G), we also compared different types of approximations (UHF and RHF) in order to know if these were compatible with each other comparing total energy, gap and geometry. Finally, one of the main results was the doping of rGOm with aluminium. Aluminium when placed at some specific sites promotes the approach of border orbitals by reducing the gap, making aluminium-doped rGOm a material with a propensity for better electrical conduction than rGOm without doping, which increases the interest in using this material for organic electronics.
5

Utvärdering av förvaltningsplaner ur ett tekniknära perspektiv : En fallstudie vid Trafikverket / Evaluation of management-plans from a technical perspective : A case study at the Swedish Transport Administration

Söderlund, Josefine, Törn, Ida January 2020 (has links)
På maintenance management modell (pm3) är den förvaltningsmodell Trafikverket adapterat till sin organisation med en indelning av verksamhetsnära och tekniknära förvaltning. Förvaltningsobjekt innehåller olika verksamhetsstöd och IT-system, dessa förvaltas genom styrdokument, så kallade förvaltningsplaner. Studien fokuserar på förvaltningsplaners användbarhet för den tekniknära förvaltningen ur ett tekniknära perspektiv. Avdelningen Informations- och Kommunikationsteknik Anläggningsinformation IT (IKTa) hade behov av att undersöka förvaltningsplanernas användbarhet och om de gav stöd åt den tekniknära förvaltningen. För att undersöka detta framtogs en frågeställning innehållande tre frågor: 1. Hur ser framtagningsprocessen för en förvaltningsplan på IKTa Trafikverket ut i dagsläget enligt den tekniknära förvaltningen; 2. Är förvaltningsplanerna användbara för förvaltningsobjekten ur ett tekniknära perspektiv; och 3. Hur säkerställs det att en förvaltningsplan är ett stöd för arbetet, och ett underlag för att främja objektivitet vid måluppfyllnad inom den tekniknära förvaltningen? Studien har bedrivits som en beskrivande fallstudie med en kvalitativ datainsamlingsmetod bestående av dokumentstudier och intervjuer. Intervjuer genomfördes med fyra Tekniknära förvaltningsansvariga och sex Tekniknära förvaltningsledare, samtliga utgör förvaltningsledningen inom den tekniknära verksamheten. Resultatet påvisar att förvaltningsobjekten är för stora och att det finns behov av delförvaltningsplaner för att öka detaljeringsnivån. Förvaltningsplansmallen behöver inte ändra rubrikstruktur, men en tydligare innehållsspecifikation för respektive rubrik är nödvändig. Det framkommer att förvaltningsplanerna i dagsläget inte används som de levande dokument de bör vara. Slutsatserna dragna är att Trafikverket behöver omformulera de mål som står i förvaltningsplanerna så de håller en högre objektivitet och mätbarhet än i dagsläget. Delförvaltningsplanerna är ofrånkomliga då de är dokumenten som håller den högre detaljeringsnivån som är uppföljningsbar. / The Swedish Transport Administration has done an adaptation of the På maintenance management model (pm3) where management has been divided into business management and technical management. A management-object includes both the business and the ITsystems. Moreover, the management-organization writes management-plans which are governing-documents for deliveries within the Swedish Transport Administration. This study focuses on the technical management perspective and the technical side of the management-plans. There was a need to study the management-plans’ usability at the Department of Information and Communication Technology – Infrastructure Information. As such, the following research questions were formulated: 1. What is the process of making management-plans in Infrastructure Information at the Swedish Transport Administration today, according to the technical management; 2. Are the management-plans useful for the management-object in the perspective of technical management; 3. How is it ensured that the management-plan is used to support the work, and a basis for objectivity when fulfilling goals within the technical management? This study was conducted in the form of a descriptive case study in which qualitative data was collected by means of interviews and document studies. The interviews included four managers and six leaders of technical management, who represent the administrative management within the technical management. The results show that the management-objects are too big, and that there is a need for sub-management-plans to acquire more details. The respondents of this study wish the management-plan was a more vivid document. The main conclusions drawn from this study are that the management-plans are useful as a follow up for activities but not for following up on goals. And that while the management-plans provide an overview of the management object, the sub-management-plans are needed to specify details
6

Den horisontella kommunikationens roll inom förvaltningsarbete / The role of lateral communication within the work in software maintenance

Vallgren, Matilda, Lundqvist, Malin January 2016 (has links)
Syftet med denna uppsats är att undersöka vad den horisontella kommunikationen har för roll inom systemförvaltning, och att undersöka vad en effektiv sådan har för påverkan på förvaltningsarbete. Då systemförvaltning är kostsamt är det viktigt för organisationer att det sker effektivt. Effektiviteten i organisationers arbete påverkas av kommunikationen och för att uppnå en effektiv kommunikation krävs en förståelse för horisontell kommunikation. Men inom styrning av systemförvaltning ligger inte fokus på kommunikation. Undersökningen genomfördes med hjälp av kvalitativa semistrukturerade intervjuer. Förvaltningsledningar på en organisation vars förvaltningsarbete styrs av förvaltningsmodellen pm3 studerades. Uppsatsens resultat visar på att en horisontell kommunikation utspelar sig inom förvaltningsarbete, det krävs en kommunikation mellan vissa arbetsroller. Den horisontella kommunikationen har också en betydande roll, då den kan hjälpa till att upprätta enhetliga arbetssätt. Resultatet visar dock att den horisontella kommunikationens funktion inte alltid utnyttjas till fullo. När den inte är effektiv kan det bidra till duplicerat arbete, förlorad och utelämnad information, samt att medarbetares kunskap förbises. Allt detta påverkar i slutändan arbetets produktivitet. Uppsatsens resultat visar att desto effektivare den horisontella kommunikationen är inom förvaltningsarbete, desto effektivare blir arbetet. / The purpose of this thesis is to examine what role lateral communication within the work in software maintenance has, and to examine how an effective lateral communication influences the maintenance work. Software maintenance is costly, therefore it is important for organizations that it is efficient. Organization’s efficiency is influenced by their communication. To attain an effective communication there needs to exist an understanding for lateral communication. Within the guiding of software maintenance there is a lack of regard to the importance of communication. The thesis was conducted using qualitative research. The research is based on semi-structured interviews with solution managers at an organization that has their software maintenance guided by the swedish maintenance management model pm3. The result of this study shows that a lateral communication occurs within the work with software maintenance, communication is required between certain roles. Lateral communication also has a significant role since it can help to uniform the work. However, the results show that the potential of lateral communication is not always used to its full extent. When it is not effective it can result in duplicated work, lost and excluded information, and coworkers’ knowledge can be overlooked. In the end the productivity of the work is affected. The study shows that the more effective the lateral communication is within the work in software maintenance, the more effective the work will become.
7

Utvärdering av pm3 som förvaltningsstyrningsmodell : En fallstudie på Trafikverket / Evaluation of pm3 as a maintenance management model : A case study at the Swedish Transport Administration

Grönberg, Oskar January 2019 (has links)
The maintenance management model (Pm3) is a management model whose goal is to contribute to the collaboration between the business and IT. An implementation of pm3 involves applying the model, it must be implemented with the business existing governance and work methods. The purpose of the study is to investigate to be able to describe and evaluate the use of pm3 as a management model in a state agency. The study is carried out at the Swedish Transport Administration and their implementation of pm3. The aim of the study is to answer the research question which is “how pm3 can be implemented and applied to be more effective?”. The strategy that has been applied is a case study. The data collection methods are interviews and document studies where qualitative data has been generated. The results of the study show a number of different positive effects that implementation of pm3 can have on a business such as better collaboration, cost effectiveness and clearer overall picture. Some challenges and problems are also identified and a lot of them can be linked to the lack of implementation of the model at the Swedish Transport Administration. To maximize the implementation of pm3, this study has come to the conclusion that it is important with internal education in the management model. This to increase the chance of a successful implementation. Taking external help from the pm3 license is also a way to improve the implementation, as it offers external help and support from external experts. After implementation, it is also important to have an active management of the model, so that the business receives support to work properly over time. Recommendations for future studies is how to follow up on your implementation and establish your governance with pm3 over time.
8

Síntese e estrutura de compostos poliaza heterocíclicos / Synthesis and structure of compounds polyaza heterocyclic

Campos, Patrick Teixeira 27 July 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work describes the synthesis of a number of polyaza heterocycles and the mechanistic study to obtain these products. Furthermore, the characterization was performed by spectroscopic method and the structural study by X-ray diffraction and theoretical calculations of molecular orbitals. The synthesis of polyaza heterocyclic compounds began from the cyclocondensation reaction between a β- enaminodiketone and 2-aminopyridine, 2-aminothiazole or 2-aminobenzoimidazole in order to achieve pyrido[1,2-a]pyrimidin-4-one, thiazole[3,2-a]pyrimidin-5-one or 2- oxo-pyrimido[1,2-a]benzimidazole, respectively, with a α-keto ester substituent, in high regioselectivity. The mechanistic proposal developed in this step is based on the semi-empirical theoretical calculations by the PM3 method. From these data it was possible to say that the reaction was controlled by frontier molecular orbital, according to values of HOMO/LUMO coefficient obtained for the reactants. In the next step, the α-keto esters previously obtained, were reacted with ethylenediamine and derivatives ledding to the pyrazinones formation and the reaction with 1,2- phenylenediamine and derivatives led to the formation quinoxalinones. The same reaction of α-keto esters with amidines did not lead to the formation of imidazolonas as expected, since only the formation of the substitution product in the ester group occurred. The reaction mechanisms proposed in these steps are also based in theoretical calculations, where it was possible to infer that the reaction was thermodynamically controlled, since the reactivity sites were less important than the stability of the intermediates. The compounds were characterized by 1D nuclear magnetic resonance experiments of such as 1H and 13C and 2D such as COSY, HETCOR and HMBC, besides of mass spectrometry. The molecular structural studies by X-ray diffraction (for the compounds that could be measured) revealed that polyaza heterocycles pyrido[1,2-a]pyrimidin-4-one, thiazole[3,2-a]pyrimidin-5-one and 2-oxo-pyrimido[1,2-a]benzimidazole are essentially plane. All these compounds showed as pattern at least one intramolecular interaction between a carbonyl oxygen atom and a carbonyl carbon via π-hole, forming a five membered pseudo-ring, which stabilizes the position of a carbonyl group. The study revealed that all structural supramolecular compounds exhibit a large number of weak hydrogen bonds of the type CH···X (where X = O, N) and the compounds which exhibited a NH group in its structure or water in the asymmetric unit formed additionally strong hydrogen bonds of the type X-H···X (where X = O, N). Since the structures studied are aromatic heterocycles, all compounds showed interactions involving π systems in their interactions like π···π and/or lone-pair···π in their crystal packing. Only one intermolecular interaction via σ-hole (C=O···S) and another via π-hole (C=O···C=O) were found. / Neste trabalho é descrita a síntese de uma série de poliaza heterociclos e o estudo mecanístico para a obtenção destes produtos. Além disso, é realizada sua caracterização utilizando métodos espectroscópicos e o estudo estrutural por difração de Raios-X e cálculos teóricos de orbitais moleculares. A síntese dos compostos poliaza heterocíclicos teve inicio a partir de reações de ciclocondensação entre uma β-enaminodicetona e 2-aminopiridina, 2-aminotiazol ou 2-aminobenzoimidazol para obter pirido[1,2-a]pirimidin-4-ona, tiazolo[3,2-a]pirimidin-5- ona e 2-oxo-pirimido[1,2-a]benzoimidazol, respectivamente, com um substituinte α- ceto éster, de maneira altamente regiosseletiva. A proposta mecanística elaborada nesta etapa está embasada em cálculos teóricos semi-empíricos pelo método PM3. A partir destes dados é possível afirmar que a reação é controlada por orbital molecular de fronteira, conforme os valores de coeficiente de HOMO/LUMO obtidos para os reagentes. Na etapa seguinte, os α-ceto ésteres, previamente obtidos, ao reagirem com etilenodiamino e derivados levaram a formação de pirazinonas, bem como, a reação com 1,2-fenilenodiamino e derivados levou a formação de quinoxalinonas como produto. A reação dos mesmos α-ceto ésteres com amidinas não levou a formação de imidazolonas como desejado, pois ocorreu apenas a formação do produto de substituição no grupo éster. Os mecanismos de reação propostos nestas etapas também estão embasados em cálculos teóricos, onde foi possível inferir que a reação foi termodinamicamente controlada, já que, a reatividade dos sítios foi menos importante que a estabilidade dos intermediários. Os compostos foram caracterizados utilizando ressonância magnética nuclear em experimentos de 1D como 1H e 13C, e 2D como COSY, HETCOR e HMBC, além de espectrometria de massas. O estudo estrutural molecular por difração de Raios-x (referente aos compostos que puderam ser medidos) revelou que os poliaza heterociclos pirido[1,2- a]pirimidin-4-ona, tiazolo[3,2-a]pirimidin-5-ona e 2-oxo-pirimido[1,2-a]benzoimidazol são essencialmente planos. Um padrão observado nestes compostos é que todos apresentam, pelo menos, uma interação intramolecular entre um átomo de oxigênio carbonílico e um carbono carbonílico via π-hole, formando um pseudo-anel de cinco membros, que estabiliza a posição de uma carbonila. O estudo estrutural supramolecular revelou que todos os compostos apresentam um amplo número de ligações de hidrogênio fracas do tipo C-H· · ·X (quando, X = O, N) e os compostos que apresentaram um grupo N-H em sua estrutura ou água na unidade assimétrica formam, adicionalmente, ligações de hidrogênio fortes do tipo X-H···X (quando, X = O, N). Como as estruturas estudadas apresentam heterociclos aromáticos, todos os compostos mostraram interações envolvendo seus sistemas π em interações do tipo π· · ·π e/ou lone-pair· · ·π em seus empacotamentos cristalinos. Apenas uma interação intermolecular via σ-hole (C=O· · ·S) e uma via π-hole (C=O· · ·C=O) foram encontradas.
9

MAINTAINING MAINTENANCE : The Importance of Evaluation and Upkeep in Maintenance Management Models

Berglin, Sebastian, Wennberg, Albin January 2022 (has links)
This thesis explores the consequences of neglect and lack of proper support and implementation in maintenance management models, specifically an old implementation of the Pm3 model. The area of study is not widely explored, with studies and evaluation of the specific model we have looked at being almost non-existent. We have conducted a qualitative case study at an IT department/company at a Swedish university and the data has been collected through interviews with different IT department leaders, as well as one interview with a representative with the company that owns and distributes the Pm3 model. The current software development methodology at the IT company studied in this thesis are agile methods but is locked down to a micro level, while the Pm3 model handles the macro level. The consequences of this are then compared against research within fields such as IT governance and IT/business alignment to find discrepancies from which the phenomena’s can be explained. With this thesis we want to explore the consequences of not maintaining maintenance management models in organizations, especially the Pm3 model as this is widely in Swedish institutions such as universities and government authorities. This thesis provides a word of caution and argue for the importance of maintenance in maintenance management models for such organizations.

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