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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.
21

Är mammaledighet en förlustaffär för kvinnliga fastoghetsmäklare? : En kvalitativ studie om mammaledighetens påverkan på kvinnans karriär. / Is maternity leave a loss of business for female real estate agents?

Davidsson, Jessica, Granbom, Gabriella January 2018 (has links)
Denna studie avsåg att beskriva hur kvinnliga fastighetsmäklare upplever att en mammaledighet kan komma att påverka deras karriärer. Vi ville undersöka om blivande mammor upplever en oro inför och efter en mammaledighet samt i vilken utsträckning de anser att lönemodellen skulle vara en påverkande faktor. Vidare ville vi undersöka om fastighetsmäklares yrke är anpassat för en mammaledighet, om konkurrensen inom branschen påverkar huruvida yrket går att kombinera med barn och om det finns några hinder som påverkar kvinnans karriär när hon återgår till arbetet efter mammaledigheten.  Tillvägagångssättet för arbetet var kvalitativa studier i form av intervjuer med kvinnliga fastighetsmäklare. Vårt resultat visade att fastighetsmäklares yrke är anpassat för mammaledighet, men däremot inte för när kvinnan väl kommer tillbaka från mammaledigheten. Majoriteten av respondenterna menade att det var som tuffast när de kom tillbaka efter sin mammaledighet. Konkurrensen inom branschen påverkar huruvida yrket går att kombinera med barn både inför och efter mammaledigheten. Det finns hinder som påverkar kvinnans karriär vid återkomsten efter mammaledigheten och det största hindret är att hon inte längre är lika tillgänglig som tidigare, på grund av att hon blivit mamma. Vi anser att vidare forskning bör studera anledningen mer djupgående till varför kvinnor valt att sluta arbeta som mäklare efter deras mammaledighet. Samt undersöka om det finns någon vision eller plan inom branschorganisationen, för att minska antalet avregistreringar bland kvinnliga mäklare som väljer att skaffa familj. Att byta ut våra kvinnliga respondenter mot män som varit pappalediga och tillämpa vår studie på dessa är ett annat förslag till vidare forskning. Studien kan inspirera branschen och förbunden att utforma mer stabila och bättre villkor, bättre förutsättningar och större trygghet för mammalediga kvinnor. Studien kan även ge arbetsgivare en inblick i, kunskap och förståelse för hur kvinnliga fastighetsmäklares karriärer påverkas av deras mammaledighet och fylla det kunskapsgap som finns. / This study was intended to describe how female real estate agents experience that maternity leave may affect their careers. We wanted to investigate whether future mothers experience an anxiety before and after maternity leave and to what extent they consider that the salary model would be an influencing factor. Furthermore, we wanted to investigate whether the profession of real estate agent is adapted to maternity leave, if the competition in the industry affects whether the profession can be combined with children and if there are any barriers that affect the woman's career when she returns to work after maternity leave. The approach for work was qualitative studies in the form of interviews with female real estate agents. Our result showed that the real estate agent's profession is adapted for maternity leave, but on the other hand not for when she returns from maternity leave. The majority of respondents said it was the toughest part when they returned after their maternity leave. The competition in the industry affects whether the profession can be combined with children both before and after maternity leave. There are barriers that affect the woman's career on the return after maternity leave and the biggest obstacle is that she is no longer as available as before, due to becoming a mother.  We believe further research should study the reason more profoundly why women chose to stop working as a real estate agent after their maternity leave. As well as investigating whether there is any vision or a plan within the industry organization, to reduce the number of deregisters among female brokers who choose to acquire a family. Replacing our female respondents, to men who have been parental leave, and apply our study on these is another suggestion for further research. The study can inspire the industry and the unions to formulate more stable and better terms, better conditions and greater security for maternity women. The study can also provide employers with an insight into, knowledge and understanding of how women's real estate agents are affected by their maternity leave and fulfill the gap of knowledge that exists.
22

Contribution to the capacity determination of semi-mobile in-pit crushing and conveying systems

Ritter, Robert 01 November 2016 (has links)
As ore grades decline, waste rock to ore ratios increase and mines become progressively deeper mining operations face challenges in more complex scenarios. Today´s predominant means of material transport in hard-rock surface mines are conventional mining trucks however despite rationalisation efforts material transportation cost increased significantly over the last decades and currently reach up to 60% of overall mining. Thus, considerations and efforts to reduce overall mining costs, promise highest success when focusing on the development of more economic material transport methods. Semi-mobile in-pit crusher and conveyor (SMIPCC) systems represent a viable, safer and less fossil fuel dependent alternative however its viability is still highly argued as inadequate methods for the long term projection of system capacity leads to high uncertainty and consequently higher risk. Therefore, the objective of this thesis is to develop a structured method for the determination of In-pit crusher and conveyor SMIPCC system that incorporates the random behaviour of system elements and their interaction. The method is based on a structured time usage model specific to SMIPCC system supported by a stochastic simulation. The developed method is used in a case study based on a hypothetical mine environment to analyse the system behaviour with regards to time usage model component, system capacity, and cost as a function of truck quantity and stockpile capacity. Furthermore, a comparison between a conventional truck & shovel system and SMIPCC system is provided. Results show that the capacity of a SMIPCC system reaches an optimum in terms of cost per tonne, which is 24% (22 cents per tonne) lower than a truck and shovel system. In addition, the developed method is found to be effective in providing a significantly higher level of information, which can be used in the mining industry to accurately project the economic viability of implementing a SMIPCC system.
23

Complexity of Constraint Satisfaction Problems for Unions of Theories

Greiner, Johannes 11 January 2022 (has links)
Constraint Satisfaction Problems (CSPs) are a class of decision problems where one usually fixes a structure A and seeks to decide whether or not a given conjunction of atomic formulas is satisfiable in A or not. It has been shown by Bodirsky and Grohe that every computational decision problem is equivalent to some CSP via a polynomial-time Turing reduction. For structures A with finite domain Zhuk and Bulatov both proved an algebraic criterion classifying in which cases the CSP of A is in P and when it is NP-hard. For some classes of structures with infinite domain, there are similar P vs NP-hard dichotomies. This thesis continues the latter line of research for CSPs of first-order theories. In this version of CSPs, a theory is fixed and one seeks to decide whether or not a given conjunction of atomic formulas is satisfiable in some model of T. Assuming that the CSPs of theories T1 and T2 are polynomial-time tractable, we prove necessary and sufficient conditions for polynomial-time tractability of the union of T1 and T2. For some classes of theories, P vs NP-hard dichotomies are proven. To achieve this, various 'combinations' of structures are examined, a technique called 'sampling' is generalized to theories and clones of polymorphisms of temporal structures are examined in detail.
24

Kombination av Design Thinking och Stage-Gate i produktutvecklingen för större företag / Combination of Design Thinking and Stage-Gate in Product Development for larger companies

MIKKONEN, ISABELLA, LAKTENA, JENNIFER January 2020 (has links)
I produktutvecklingen förlitar man sig ofta på processer för att driva igenom lyckade projekt, inte minst i företag av större karaktär. En traditionell process som än idag är dominerande i många stora företag är Stage-Gate. Processen är av linjär karaktär och anses vara väldigt effektiv. En uppkommande process med syfte att främja kreativitet är Design Thinking. Processen är iterativ och sätter användaren i fokus. Syftet med detta kandidatexamensarbete är att undersöka hur man i produktutvecklingen hos större etablerade företag kombinerar de två olika processerna Design Thinking och Stage-Gate. Arbetet undersöker kombinationen av en mer iterativ process som Design Thinking och en linjär och mer traditionell Stage-Gate-process och tar reda i vilken mån dessa processer används samt när och varför de används. Arbetet ska också undersöka ifall det finns någon pågående utveckling av processer och i så fall vad en sådan utveckling baseras på. Rapporten grundar sig i en litteraturstudie för att skapa en förståelse om nuvarande kunskapsläge samt undersöka olika synsätt i ämnet. Arbetet bygger också på en empirisk studie av två stora företag i form av semistrukturerade intervjuer. Respondenterna på företagen arbetar aktivt med produktutvecklingsarbete och besitter kunskap om båda processerna Design Thinking och Stage-Gate. Informationen som genererats har sedan tolkats, analyserats samt diskuterats. Slutsatserna som kan dras från undersökningen är att i stora företag används till störst del en Stage-Gatead process då det är viktigt med en tydlig struktur i stora företag. Design Thinking används mest som ett komplement och i situationer då problemet inte är väldefinierat. Utveckling av befintliga processer sker löpande men då handlar det främst om finjustering, att helt byta process är inget som är relevant. / In product development, companies often rely on processes to achieve successful projects, not least in companies of a larger size. A traditional process that is still dominant in many large companies today is Stage-Gate. The process is linear and is considered to be very effective. An emerging process with the goal to encourage creativity is Design Thinking. The process is iterative and puts the user in focus. The purpose of this bachelor's thesis is to investigate how the product development of larger, more established companies combines the two processes Design Thinking and Stage-Gate. The thesis examines the combination of a more iterative process such as Design Thinking and a linear and more traditional Stage-Gate process and analyzes to what extent these processes are used as well as when and why. The report will also investigate if there is any ongoing development of processes and, if so, what such a development is based on. The report is grounded on a literature study to create an understanding of the current state of knowledge and to explore different perspectives within the subject. The thesis is also based on an empirical study of two large companies where semi-structured interviews are used. The respondents at the companies work with product development and have knowledge of both the Design Thinking and Stage-Gate processes. The information generated has then been interpreted, analyzed and discussed. The conclusions that can be drawn from the study are that in large companies a Stage-Gated process is used to a large extent, since it is important to have a clear structure in large companies. Design Thinking is mostly used as a complement and in situations where the problem is not well defined. Development of existing processes is ongoing, but is mainly about fine-tuning, to completely change the process is not relevant.
25

I Gripdjurets grepp : om skandinavisk djurornamentik, bildtolknings metodik och djurhuvudformiga spännen / The grip of the beast : Scandinavian animal art, image interpretation methodology and animal-head brooches

Melander, Victor Niels Love January 2013 (has links)
Animal art is one of the more mystical aspects of Scandinavian Iron Age culture. It has foremost been regarded in the light of art and style history. Interpretation has also – mainly from the 1990s and onwards – been made through iconographic analysis. But the problem here is that iconography requires textual analogy, something that the Scandinavian Iron Age lacks. The purpose of this paper is to lift some of the ”mystical fog” that engulfs the scandinavian animal art, by developing a method for interpretation of pre-historic images that evades the flaws in the iconographic method. This by doing an interpretation of the gripping beast motif on Gotlandic Viking Age animal-head brooches. The study is divided into three parts. Part one focuses on reception within research history and how the use of language and methodological approaches shapes the perception of animal art within it's own time, it also discusses animal art in the light of style, motif and communication. Part two aims to outline a method for pre-historic image interpretation, a structuralistic iconology with addition of contextualization and anthropological theories of agency. The chapter also discusses the cosmological order through means of ”structuralistic iconology”. Finally part three contextualizes the gripping beast to the object – the animal head-brooch – through notions of use, combination and age. Concluding that the gripping beast should be understood as a hybrid creature closely linked to ancestry, odal and the fatalistic worldview of Iron Age Scandinavia.
26

Kombination geodätischer Raumbeobachtungsverfahren zur Realisierung eines terrestrischen Referenzsystems

Seitz, Manuela 06 August 2009 (has links) (PDF)
Globale terrestrische Referenzsysteme und deren Realisierungen, die sogenannten Referenzrahmen, sind die Grundlage für die Beschreibung der Figur der Erde und ihrer Orientierung im Weltraum sowie für die Referenzierung von Vorgängen auf der Erdoberfläche und im nahen Umfeld der Erde. Die Realisierung des Internationalen Terrestrischen Referenzsystems ist eine der zentralen Aufgaben der Geodäsie. Sie erfolgt durch Kombination von Beobachtungsdaten geodätischer Raumbeobachtungsverfahren. Besondere Bedeutung kommen dabei dem Verfahren der Interferometrie auf sehr langen Basislinien, der Laserentfernungsmessung zu Satelliten sowie dem Globalen Positionierungssystem zu. Jedes dieser Verfahren weist besondere Stärken bei der Bestimmung geodätischer Parameter auf und trägt wesentlich zur Realisierung des Referenzsystems bei. In dieser Arbeit werden Methoden zur Berechnung einer zeitabhängigen und einer zeitunabhängigen Realisierung aus den Beobachtungen der genannten Verfahren entwickelt. Beide Ansätze basieren auf der Kombination bedingungsfreier Normalgleichungen, die aus der homogenen Auswertung der Beobachtungen resultierenden. Diese Vorgehensweise kann als gute Approximation der direkten Kombination der Beobachtungen angesehen werden, die bisher nicht erfolgreich umgesetzt werden konnte. Vom Internationalen Erdrotations- und Referenzsystemdienst (IERS) werden Referenzrahmen basierend auf zeitlich hochaufgelösten Eingangsdaten berechnet. Für die jüngste Lösung des IERS, den ITRF2005, wurden Stationskoordinaten und Erdrotationsparameter (Polkoordinaten und UT1-UTC) erstmalig konsistent ausgeglichen. Entsprechend diesem IERS-Standard werden auch in dieser Arbeit Eingangsdaten mit einer zeitlichen Auflösung von einem Tag beziehungsweise einer Woche verwendet. Zusätzlich zu den genannten Parametern werden Nutations- und bei der zeitunabhängigen Realisierung Troposphärenparameter berücksichtigt. Die zeitabhängige und die zeitunabhängige Realisierung unterscheiden sich hinsichtlich des Zeitraums, aus welchem Beobachtungen berücksichtigt werden und damit hinsichtlich ihrer Parametrisierung, ihres Informationsgehalts, ihres Gültigkeitsbereichs und ihrer Genauigkeit. Es werden spezifische Kombinationsmodelle entwickelt, die diese Eigenschaften berücksichtigen. Da sich Beobachtungen verschiedener Raumbeobachtungsverfahren in aller Regel nicht auf gemeinsame Referenzpunkte beziehen, müssen zur Kombination der Stationsnetze Differenzvektoren zwischen dicht beieinander liegenden Referenzpunkten verschiedener Verfahren eingeführt werden. Die gemessenen Differenzvektoren weisen teilweise große Diskrepanzen zu den Koordinatendifferenzen auf, die aus den Raumbeobachtungsverfahren bestimmt werden. Deshalb müssen geeignete gemessene Differenzvektoren für die Kombination ausgewählt werden. Zwei Kriterien werden für die Auswahl formuliert: Die Konsistenz der kombinierten Lösung soll maximal sein, und die Geometrie der verfahrensspezifischen Stationsnetze soll in der Kombination erhalten bleiben. Zur Quantifizierung der Konsistenz werden die Polkoordinaten herangezogen. Es wird gezeigt, dass diese sich in ihrer Eigenschaft als globale Parameter, die aus allen genannten Beobachtungsverfahren geschätzt werden können, hervorragend zur Beurteilung der Konsistenz eignen. Für beide Realisierungen wird nachgewiesen, dass die Kombination der verschiedenen Beobachtungsverfahren für die Mehrzahl der Parameter zu einer Genauigkeitssteigerung im Vergleich zu den verfahrensspezifischen Lösungen führt. Für einige der Parameter wird eine Verbesserung von 10\% und mehr erreicht. Es wird eine Methode zur Kombination von Troposphärenparametern entwickelt und für die Realisierung des zeitunabhängigen Referenzrahmens getestet. Die Kombination der Troposphärenparameter führt zu einer weiteren Verbesserung der Genauigkeit der kombinierten Lösung. Eine Gegenüberstellung des zeitabhängigen und des zeitunabhängigen Referenzrahmens zeigen die unterschiedlichen Potentiale beider Lösungen. Anhand der Ergebnisse der Arbeit werden Empfehlungen zur Verbesserung öffentlich bereitgestellter Kombinationsprodukte formuliert. Hervorzuheben ist dabei, dass die Kombination der Beobachtungsverfahren auf der Ebene der Normalgleichungen oder - wenn möglich - auf Ebene der Beobachtungsgleichungen durchgeführt werden sollte, und dass die speziellen Eigenschaften der Parameter im Kombinationsprozess besser genutzt werden sollten. / Global terrestrial reference systems and their realizations, the so called reference frames, are fundamental for the description of the Earth's shape and its orientation in space and for referencing changes on the Earth's surface and its planetary environment. The Realization of the International Terrestrial Reference System is one of the main tasks of geodesy. It is achieved by the combination of observation data of different space geodetic techniques. The most important techniques are the Very Long Baseline Interferometry, Satellite Laser Ranging and the Global Positioning System. Each of these techniques has individual strengths with respect to the estimation of geodetic parameters and contributes significantly to the realization of the terrestrial reference system. In this thesis methods are developed, which allow for the realization of a time-dependent as well as for a time-independent reference frame from space observation data. Both methods are based on the combination of free normal equations which result from the homogeneous analysis of the different observation types. This approach is a good approximation for the direct combination of observations, which has not yet been implemented successfully. The International Earth Rotation and Reference Systems Service (IERS) computes reference frames from input data with high temporal resolution. For the most recent solution, the ITRF2005, station coordinates and Earth rotation parameters (pole coordinates and UT1-UTC) were estimated consistently for the first time. In analogy to the IERS standards, input data with daily and weekly resolution are used in this work. In addition to the above mentioned parameters, nutation and troposphere parameters are considered. The time-dependent and the time-independent reference frame are based on observation data of different time spans (two years and one day respectively). Consequently, they are characterised by a different parameterisation and show discrepancies with respect to information content, validity, and accuracy. This requires the development of individual combination models for both realizations. Usually, observations of different space geodetic techniques do not refer to a common reference point. Neighbouring reference points of different techniques are combined by introducing terrestrial difference vectors. In some cases the comparison of the terrestrial difference vectors and the coordinate differences computed from the solutions of the space geodetic techniques show large discrepancies. Thus, the selection of difference vectors which are suitable for the combination is essential. Two criteria for the selection are formulated: The consistency of the combined solution shall be maximal and the geometry of the technique specific station networks shall not be changed by the combination. The consistency is quantified on the basis of the pole coordinates. It is demonstrated, that the pole coordinates are qualified to describe the consistency, since they are global parameters that can be estimated from the observations of all techniques. For both realizations it is shown, that the combination leads to an improvement of accuracy for most of the parameters compared to the technique specific solutions. For some parameters an improvement of 10\% or more is achieved. Additionally, a method for the combination of troposphere parameters is developed and tested for the computation of the time-independent reference frame. The computation of the troposphere parameters leads to a further increase of the accuracy of the combined solution. The comparison of the time-dependent and the time-independent reference frame discloses the individual potentials of both frames. Based on the results, recommendations for the improvement of official combination products are formulated. The most important suggestions are, that the combination of space geodetic techniques shall be performed on the level of normal equations, or if possible on the level of observations. Furthermore, the individual characteristics of the parameters should be used more effectively in the combination process.
27

Gemcitabine and Docetaxel for Epithelioid Sarcoma: Results from a Retrospective, Multi-Institutional Analysis

Pink, Daniel, Richter, Stephan, Gerdes, Sebastian, Andreou, Dimosthenis, Tunn, Per-Ulf, Busemann, Christoph, Ehninger, Gerhard, Reichardt, Peter, Schuler, Markus K. 20 May 2020 (has links)
Objective: Epithelioid sarcoma (ES) presents unique clinical features in comparison to other sarcoma subtypes. Data regarding the benefits of chemotherapy are very limited. Combination regimens using gemcitabine and docetaxel (Gem/Doce) have proven to be effective, especially in uterine and nonuterine leiomyosarcoma. Yet, there is no available data on the efficacy of Gem/Doce in ES. Methods: A retrospective analysis of the three participating institutions was performed. Twenty-eight patients with an ES diagnosis presented at one of the participating institutions between 1989 and 2012. Of this group, 17 patients received chemotherapy. Results: Patients’ median overall survival (OS) after the beginning of palliative chemotherapy was 21 months, and the 1-year OS was 87%. Twelve patients received Gem/Doce with a clinical benefit rate of 83%. The median progression-free survival (PFS) was 8 months for all patients receiving Gem/Doce. The best response was complete remission in 1 patient and partial remission in 6 patients. All 6 patients receiving Gem/Doce as a first-line treatment showed measurable responses with a median PFS of 9 months. Conclusions: In this retrospective study, Gem/Doce was an effective chemotherapeutic regimen for ES. Prospective studies are needed to better assess the effects of this combination drug therapy.
28

Val av plockmetod för effektivare materialförsörjning vid kundanpassad produktion - En fallstudie på ATEA Logistics AB / Efficient material supply in customized production via selection of picking methods - A case study at ATEA Logistics AB

Leijonqvist, Simon, Albin, Larsson January 2020 (has links)
Studien är utförd på ATEA logistics med syftet att skapa förståelse för hur man kan kombinera två olika plockmetoder i materialförsörjningen. Målet med arbetet är att ta fram en modell som beslutsunderlag för hur denna kombination ska se ut med hjälp av kunskap angående påverkande faktorer. Resultatet är framtaget genom litteraturstudie kring plockmetoder samt egna mätningar och observationer på fallföretaget. Det konstaterades med hjälp av ett faktabaserat beslutsunderlag i form av jämförelsetider att man kunde spara upp till 295 sekunder på en given plockrunda hos fallföretaget. Det har då konstaterats att man med hjälp av kvantifierbara beslutsmodeller kan skapa kortare ledtider i materialförsörjningen med hjälp av en kombination av plockmetoder. / This report is a case study, which was conducted at ATEA Logistics AB. It’s purpose was to create understanding of how a combination of two picking methods can be used in materials supply. From this understanding the goal was to design a decision making model for when each of the methods is to be used. Literarry research, time studies, observations and interviews have been used to reach this goal. By calculating comparative times for each method, with the use of a factual decision making model, it was determined that the case company could save up to 295 seconds in a single picking round. From this result it was concluded that by using quantifiable and factual decision models, materials supply can be made more efficient by the use of a combination of picking methods.
29

Kombination geodätischer Raumbeobachtungsverfahren zur Realisierung eines terrestrischen Referenzsystems

Seitz, Manuela 04 December 2008 (has links)
Globale terrestrische Referenzsysteme und deren Realisierungen, die sogenannten Referenzrahmen, sind die Grundlage für die Beschreibung der Figur der Erde und ihrer Orientierung im Weltraum sowie für die Referenzierung von Vorgängen auf der Erdoberfläche und im nahen Umfeld der Erde. Die Realisierung des Internationalen Terrestrischen Referenzsystems ist eine der zentralen Aufgaben der Geodäsie. Sie erfolgt durch Kombination von Beobachtungsdaten geodätischer Raumbeobachtungsverfahren. Besondere Bedeutung kommen dabei dem Verfahren der Interferometrie auf sehr langen Basislinien, der Laserentfernungsmessung zu Satelliten sowie dem Globalen Positionierungssystem zu. Jedes dieser Verfahren weist besondere Stärken bei der Bestimmung geodätischer Parameter auf und trägt wesentlich zur Realisierung des Referenzsystems bei. In dieser Arbeit werden Methoden zur Berechnung einer zeitabhängigen und einer zeitunabhängigen Realisierung aus den Beobachtungen der genannten Verfahren entwickelt. Beide Ansätze basieren auf der Kombination bedingungsfreier Normalgleichungen, die aus der homogenen Auswertung der Beobachtungen resultierenden. Diese Vorgehensweise kann als gute Approximation der direkten Kombination der Beobachtungen angesehen werden, die bisher nicht erfolgreich umgesetzt werden konnte. Vom Internationalen Erdrotations- und Referenzsystemdienst (IERS) werden Referenzrahmen basierend auf zeitlich hochaufgelösten Eingangsdaten berechnet. Für die jüngste Lösung des IERS, den ITRF2005, wurden Stationskoordinaten und Erdrotationsparameter (Polkoordinaten und UT1-UTC) erstmalig konsistent ausgeglichen. Entsprechend diesem IERS-Standard werden auch in dieser Arbeit Eingangsdaten mit einer zeitlichen Auflösung von einem Tag beziehungsweise einer Woche verwendet. Zusätzlich zu den genannten Parametern werden Nutations- und bei der zeitunabhängigen Realisierung Troposphärenparameter berücksichtigt. Die zeitabhängige und die zeitunabhängige Realisierung unterscheiden sich hinsichtlich des Zeitraums, aus welchem Beobachtungen berücksichtigt werden und damit hinsichtlich ihrer Parametrisierung, ihres Informationsgehalts, ihres Gültigkeitsbereichs und ihrer Genauigkeit. Es werden spezifische Kombinationsmodelle entwickelt, die diese Eigenschaften berücksichtigen. Da sich Beobachtungen verschiedener Raumbeobachtungsverfahren in aller Regel nicht auf gemeinsame Referenzpunkte beziehen, müssen zur Kombination der Stationsnetze Differenzvektoren zwischen dicht beieinander liegenden Referenzpunkten verschiedener Verfahren eingeführt werden. Die gemessenen Differenzvektoren weisen teilweise große Diskrepanzen zu den Koordinatendifferenzen auf, die aus den Raumbeobachtungsverfahren bestimmt werden. Deshalb müssen geeignete gemessene Differenzvektoren für die Kombination ausgewählt werden. Zwei Kriterien werden für die Auswahl formuliert: Die Konsistenz der kombinierten Lösung soll maximal sein, und die Geometrie der verfahrensspezifischen Stationsnetze soll in der Kombination erhalten bleiben. Zur Quantifizierung der Konsistenz werden die Polkoordinaten herangezogen. Es wird gezeigt, dass diese sich in ihrer Eigenschaft als globale Parameter, die aus allen genannten Beobachtungsverfahren geschätzt werden können, hervorragend zur Beurteilung der Konsistenz eignen. Für beide Realisierungen wird nachgewiesen, dass die Kombination der verschiedenen Beobachtungsverfahren für die Mehrzahl der Parameter zu einer Genauigkeitssteigerung im Vergleich zu den verfahrensspezifischen Lösungen führt. Für einige der Parameter wird eine Verbesserung von 10\% und mehr erreicht. Es wird eine Methode zur Kombination von Troposphärenparametern entwickelt und für die Realisierung des zeitunabhängigen Referenzrahmens getestet. Die Kombination der Troposphärenparameter führt zu einer weiteren Verbesserung der Genauigkeit der kombinierten Lösung. Eine Gegenüberstellung des zeitabhängigen und des zeitunabhängigen Referenzrahmens zeigen die unterschiedlichen Potentiale beider Lösungen. Anhand der Ergebnisse der Arbeit werden Empfehlungen zur Verbesserung öffentlich bereitgestellter Kombinationsprodukte formuliert. Hervorzuheben ist dabei, dass die Kombination der Beobachtungsverfahren auf der Ebene der Normalgleichungen oder - wenn möglich - auf Ebene der Beobachtungsgleichungen durchgeführt werden sollte, und dass die speziellen Eigenschaften der Parameter im Kombinationsprozess besser genutzt werden sollten. / Global terrestrial reference systems and their realizations, the so called reference frames, are fundamental for the description of the Earth's shape and its orientation in space and for referencing changes on the Earth's surface and its planetary environment. The Realization of the International Terrestrial Reference System is one of the main tasks of geodesy. It is achieved by the combination of observation data of different space geodetic techniques. The most important techniques are the Very Long Baseline Interferometry, Satellite Laser Ranging and the Global Positioning System. Each of these techniques has individual strengths with respect to the estimation of geodetic parameters and contributes significantly to the realization of the terrestrial reference system. In this thesis methods are developed, which allow for the realization of a time-dependent as well as for a time-independent reference frame from space observation data. Both methods are based on the combination of free normal equations which result from the homogeneous analysis of the different observation types. This approach is a good approximation for the direct combination of observations, which has not yet been implemented successfully. The International Earth Rotation and Reference Systems Service (IERS) computes reference frames from input data with high temporal resolution. For the most recent solution, the ITRF2005, station coordinates and Earth rotation parameters (pole coordinates and UT1-UTC) were estimated consistently for the first time. In analogy to the IERS standards, input data with daily and weekly resolution are used in this work. In addition to the above mentioned parameters, nutation and troposphere parameters are considered. The time-dependent and the time-independent reference frame are based on observation data of different time spans (two years and one day respectively). Consequently, they are characterised by a different parameterisation and show discrepancies with respect to information content, validity, and accuracy. This requires the development of individual combination models for both realizations. Usually, observations of different space geodetic techniques do not refer to a common reference point. Neighbouring reference points of different techniques are combined by introducing terrestrial difference vectors. In some cases the comparison of the terrestrial difference vectors and the coordinate differences computed from the solutions of the space geodetic techniques show large discrepancies. Thus, the selection of difference vectors which are suitable for the combination is essential. Two criteria for the selection are formulated: The consistency of the combined solution shall be maximal and the geometry of the technique specific station networks shall not be changed by the combination. The consistency is quantified on the basis of the pole coordinates. It is demonstrated, that the pole coordinates are qualified to describe the consistency, since they are global parameters that can be estimated from the observations of all techniques. For both realizations it is shown, that the combination leads to an improvement of accuracy for most of the parameters compared to the technique specific solutions. For some parameters an improvement of 10\% or more is achieved. Additionally, a method for the combination of troposphere parameters is developed and tested for the computation of the time-independent reference frame. The computation of the troposphere parameters leads to a further increase of the accuracy of the combined solution. The comparison of the time-dependent and the time-independent reference frame discloses the individual potentials of both frames. Based on the results, recommendations for the improvement of official combination products are formulated. The most important suggestions are, that the combination of space geodetic techniques shall be performed on the level of normal equations, or if possible on the level of observations. Furthermore, the individual characteristics of the parameters should be used more effectively in the combination process.
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Traditionell budget och rullande prognoser : Hur ett konsultföretag kombinerar traditionell budget och rullande prognoser för att styra sin verksamhet

Björendahl, Fanny, Jonsson, Ellen January 2022 (has links)
Inledning: Traditionell budget har fått mycket kritik under åren vilket har resulterat i att nya alternativa metoder har växt fram. Ett alternativ till den traditionella budgeten är rullande prognoser, vilket också har erhållit en del kritik. Det är vanligt att kombinera dessa metoder men däremot finns det inte mycket forskning om hur detta gör samt varför företag väljer att kombinera dessa styrmedel. Syfte: Syftet med denna studie är att skapa en förståelse för hur och varför ett företag styr sin verksamhet genom att använda en kombination av en traditionell budget och rullande prognoser. Metod: Studien utgår från en kvalitativ metod med ett abduktivt angreppssätt. Den empiriska datan har samlats in genom semistrukturerade intervjuer med respondenter med olika befattningar på företaget. Intervjuerna har även kompletterats med internt material som har tillhandahållits från fallföretaget. Slutsats: Fallföretaget använder sig av en traditionell budget och rullande prognoser som ett komplement till varandra. Företaget har synkat processerna vilket har gjort att två processer blir en. De använder styrmedlena till störst del till samma syften, däremot används de för olika tidsaspekter. Att kombinera dessa styrmedel har inte visat sig vara tidskrävande för företaget, vilket kan vara till följd av att de har en gemensam process för båda styrmedlena och för att de används för liknande syften. De orsaker som identifierades till att företaget använde sig av en kombination av styrmedlena är för att styrelsen vill det, de är vana vid det och för att de ska kunna erhålla en bättre kontroll över verksamheten. / Introduction: Traditional budgeting has received much criticism over the years, which has resulted in the emergence of new alternative methods. An alternative to the traditional budget is rolling forecasts, which have also received some criticism. It is common to combine these methods, but there is not much research on how this is done and why companies choose to combine these instruments. Purpose: The purpose of this study is to create an understanding of how and why a company manages its business by using a combination of a traditional budget and rolling forecasts. Method: The study is based on a qualitative method with an abductive approach. The empirical data has been collected through semi-structured interviews with respondents with different positions at the company The interviews have also been supplemented with internal material provided by the case company. Conclusion: The case company uses a traditional budget and rolling forecasts as a complement to each other. The company has synchronized the processes, which has made two processes one. They mostly use the instruments for the same purposes, however, they are used for different time aspects. Combining these instruments has not proved to be time consuming for the company, which may be because they have a common process for both instruments and because they are used for similar purposes. The company uses a combination of the instruments because the board wants it, they are used to it and because they want to obtain better control over the business.

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