A new numerical analysis method, dispersion vs. absorption plots (DISPA), has been developed for ESR. This method may be used for semi-quantitative line-shape studies and is useful both as a diagnostic and analytical tool. In addition it provides a method of automatic phasing for magnetic resonance spectra. Numerous examples of its applications, both simulated and experimental are presented, with emphasis on spin-probe studies. The digital acquisition and processing methods used for these studies are also briefly discussed. ESR and NMR relaxation time studies of the bis(dialkyl-N-carbodithioate) metal(II) class of spin-probes have been performed. The T₁,'s of ¹³C and ²H enriched nickel complex were measured by NMR. The line-widths of ⁶³Cu complex were measured by ESR and analysed by Redfield theory. The two sets of results were combined to give the principal elements of the rotational diffusion tensor for the pyrollidine derivative in toluene. This is the first time that ESR and NMR studies have been combined to measure a diffusion tensor. A general strategy for this approach is presented. ESR data from previous work has been re-analysed in the light of the new results. The analysis shows that the commonly used assumption of isotropic diffusion is extremely misleading. / Science, Faculty of / Chemistry, Department of / Graduate

Scania verkar på en global marknad med tillverkning på flera orter och en förutsättning för att kunna garantera kvalité på de produkter som levereras, oavsett vart de produceras, är ett konsekvent tillämpat standardiserat arbetssätt vid tillverkning och montering. Monteringsbeskrivningar - eller elementblad som de benämns på Scania är en viktig del i att kommunicera detta "standardiserade arbetssätt" över hela företaget och alla desstillverkningsenheter. Det s.k. standardiserade arbetssättet är relativt väl utvecklat mellan de verkstäder som monterar samma typ av huvudkomponenter, men i ett vidare perspektiv så förekommer det mellan olika enheter såväl skillnader i presentation av data i elementblad som arbetsmetoder för att ta fram dem. Det finns därför ett uttalat behov av att standardisera såväl framtagning som presentation av data i elementblad. Syftet med detta examensarbete har varit att utveckla och testa en effektiv arbetsprocess för att tidsätta och ta fram lättförståeliga elementblad med stöd av digitala underlag. Därmed har en koppling mellan processerna för digital provmontering och framtagning av elementblad skapats. Ett förslag till arbetsmodell för framtagning av elementblad för chassimonteringen presenteras. I denna används de digitala underlagen både vid tidssättning med hjälp av standardtidssystem och för framtagning av bilder för beskrivning av monteringsoperationerna. Arbetsmodellen är anpassad till de applikationer som Scania använder idag. Resultatet av den enkät där arbetsprocessens effektivitet utvärderats visar att den har potential att leverera elementblad av högre kvalité än dagens process. / Scania operates in a global market and has manufacturing at multiple sites worldwide. Independently of where they are made, a consistently applied standardized work is a fundamental necessity to ensure the quality of their products. Assembly instructions – or element sheets as they are called at Scania, play an important role in communicating this standardized work across the entire company. The so called standardized work is relatively well established amongst production units which assembles the same type of key component, but in a wider perspective there are differences in presentation of the data in element sheets as well as the work methods used to create them. This evokes the need to standardize the creation process as well as how the data of the element sheets are presented. The purpose of this study has been to develop and test an efficient work process where digital models are used for creating element sheets with a high level of comprehensibility, and in addition for conducing predetermined motion time study (PMTS) of the activities included in them. Thus, a link between digital test assembly (DTA) and the process for creating element sheets has been established. A proposal for a work process for the creation of element sheets for the chassis assembly is presented. In this, the use of digital models while conducting PMTS as well as when extracting illustrations for describing assembly operations are fundamental. The work process is adapted to fit Scania’s existing software portfolio. The result of the survey where the work process efficiency was evaluated showed that it has the potential to deliver element sheets with a higher quality than the process of today.

Syftet med studien var att undersöka hur sjuksköterskor på en allmänpediatrisk avdelning disponerar sin tid gällande administrativa arbetsuppgifter jämfört mot direkt och indirekt patientkontakt. För att granska detta fenomen utfördes en aktivitetsstudie. Metod designen var icke experimentell deskriptiv observationsstudie. Där sju olika sjuksköterskor följdes under femton dagar där tidmätning skedde av på förhand kategoriserade aktiviteter. Kategoriseringsschema innehöll nio olika kategorier. Resultatet visade att 19,53 procent av arbetspasset vilket motsvarar 97 minuter spenderades med direkt patientkontakt respektive de 24,3 procent vilket motsvarar 120 minuter per dag till administrativa göromål. Dessutom uppmättes det att sjuksköterskorna blev avbrutna i snitt 26 gånger under ett åtta timmars arbetspass vilket resulterar till 3,25 avbrott per timme. Forskarnas slutsats är att det finns flera fördelar med ökad tid för patientkontakt och att detta är synnerhet gällande på en allmänpediatrisk avdelning. / The aim of the study was to examine how nurses at a general pediatric unit dispose of their time regarding administrative duties compared to direct interaction with the patient. To appropriately survey this phenomenon an activity study was conducted. The method for data collection was a nonexperimental descriptive observational study where seven nurses were followed for a total of fifteen days where the amount of time of their activities where noted according to an activity schedule that was formed beforehand. The schedule contained nine categories including the amount of interruptions nurses where subject to. The result of the study showed that roughly 19,53 percent of the nurses’ time, which is the equivalent to 97 minutes, were spent directly with the patients compared to the 24,3 percent, which amounts to 120 minutes a day, she spent with administrative tasks. Furthermore it was found that a nurse is in average interrupted 26 times during an eight hour shift which gives an average of 3,25 interruptions every hour. In conclusion the authors found ground that there are many benefits with increased nurse-patient time and believe this is especially true in a general pediatric unit.

<p>This dissertation argues that social power relations in Canada are deeply tied to the cultural models of time that have been assumed and rejected throughout the country’s history, and that Canadian literature and other arts serve a vital function in both witnessing and questioning these relationships. I begin by tracing the competing temporal frameworks that have taken hold in Canada, from the Gregorian calendar, to “standard” clock time, to immigration policies that cause people who are considered undesirable to wait longer periods of time for legal status. I suggest that the profound consequences temporal structures have on social relations necessitate a sustained study of how Canadian cultural and literary productions engage with the idea of time. After outlining the contested temporalities that serve broadly as sites of power, I turn to Canadian novels, poems, plays, and visual art to explore the difficult negotiations between individual and social experiences of time. These texts reveal that while broad cultural temporalities indeed shape the measuring out of individual lives, this shaping process functions differently for different people. In particular, I examine how forms of temporal agency and disempowerment are closely linked to the categories of age, class, gender, sexuality, race, and indigeneity. Finally, I examine texts that question existing temporal structures and explore alternative temporalities. While normative temporality is often depicted as unyielding, stories about catastrophic social disruptions portray normative time as a makeshift apparatus always on the verge of collapse. Such stories indicate that while the construction of new, more just models of time is always possible, no temporal structure is free from the politics of social power relations.</p> / Doctor of Philosophy (PhD)

Nanotechnology is the science and engineering of creating functional materials by precise control of matter at nanometer (nm) length scale and exploring novel properties at that scale. It is vital to understand the quantum mechanical phenomena manifested at nanometer scale dimensions since that will enable us to precisely engineer quantum mechanical properties to realize novel device functionalities. This dissertation investigates optical and electronic properties of compound and transition metal doped compound semiconductor nanowires with a view to exploiting them for a wide range of applications in semiconductor electronic and optical devices. In this dissertation work, basic concepts of optical and electronic properties at low dimensional structures will be discussed in chapter 1. Chapter 2 discusses the nanofabrication technique employed to fabricate highly ordered nanowires. Using this method, which is based on electrochemical self-assembly techniques, we can fabricate highly ordered and size controlled nanowires and quantum dots of different materials. In Chapter 3, we report size dependent fluorescence spectroscopy of ZnSe and Mn doped ZnSe nanowires fabricated by the above method. The nanowires exhibit blue shift in the emission spectrum due to quantum confinement effect, which increases the effective bandgap of the semiconductor. We found that the fluorescence spectrum of Mn doped ZnSe nanowires shows high luminescence efficiency, which seems to increase with increasing Mn concentration. These results are highly encouraging for applications in multi spectral displays. Chapter 4 investigates field emission results of highly ordered 50 nm tapered ZnO nanowires that were also fabricated by electrochemical self-assembly. Subsequent to fabrication, the nanowires tips are exposed by chemical etching which renders the tips conical in shape. This tapered shape concentrates the electric field lines at the tip of the wires, and that, in turn, increases the emission current density while lowering the threshold field for the onset of field emission. Measurement of the Fowler-Nordheim tunneling current carried out in partial vacuum indicates that the threshold electric field for field emission in 50-nm diameter ZnO nanowires is 15 V/µm. In this study we identified the key constraint that can increase the threshold field and reduce emission current density. In Chapter 5 we report optical and magnetic measurement of Mn-doped ZnO nanowires. Hysterisis measurements carried out at various temperatures show a ferromagnetic behavior with a Curie temperature of ~ 200 K. We also studied Mn-doping of the ZnO nanowires. The room temperature fluorescence spectroscopy of Mn-doped ZnO nanowires shows a red-shift in the spectra compared to the undoped ZnO nanowires possibly due to strain introduced by the dopants in the nanowires. Finally, in Chapter 6, we report our study of the ensemble averaged transverse spin relaxation time (T2*) in InSb thin films and nanowires using electron spin resonance (ESR) measurement. Unfortunately, the nanowires contained too few spins to produce a detectable signal in our apparatus, but the thin films contained enough spins (> 109/cm2) to produce a measurable ESR signal. We found that the T2* decreases rapidly with increasing temperature between 3.5 K and 20 K, which indicates that spin-dephasing is primarily caused by spin-phonon interactions.

För att Nordic Paper Seffle AB i framtiden ska kunna utöka sin produktion eller byta ut nuvarande komponenter behöver de grunda sina beslut i fakta. På produktionsavdelningen finns idag varken dokumenterad cykeltid eller aktiviteter noterade för deras tre förpackningsmaskiner. Genom detta examensarbete kommer en tidsstudie genomföras i syfte att dokumentera maskinernas aktiviteter och identifiera flaskhalsar i flödena. Metoden som arbetet bygger på, har en grund inom Lean med verktyg och begrepp som beskrivs inom filosofin. Arbetet kommer inte involvera någon tidsstudie för operatörerna på något sätt vilket betyder att endast förpackningsmaskinerna kommer studeras. Kringarbete kommer nämnas för att ge en klarare bild på förloppet. De noterade aktiviteterna redovisas i löpande tabeller tillsammans med deras cykeltider. Efter vardera förpackningsmaskinen följer analys för hela grupper eller enskilda aktiviteter som flaskhalsar. Analysen för resultatet kommer ses ur ett effektivitetsperspektiv och liknas med bland annat de punkter som Lean presenterar för slöserier. Här kommer flaskhalsarna beskrivas samt varför de anses vara flaskhalsar för förpackningsmaskinerna. I samband redogörs även en trolig anledning och lösning för problemet. Resultatet beräknas hjälpa företaget att växa samt lägga en grund för framtida studier inom relaterade områden som kommer beskrivas ytterligare i arbetets slutsats. / If Nordic Paper Seffle AB is going to expand or exchange parts in their production in the future, they have to base their decisions in facts. Today, the production department doesn’t have any cycle times, or activities documented for their three packaging machines. By doing this thesis a time study will be performed with the purpose of documenting the machines activities and to identify bottle necks in the value stream. The thesis has its’ roots in Lean, with tools and concepts profound to the philosophy. The work won’t involve any time studies of the operators in any way. This means that it’s only the packaging machines which will be studied. Circular work will be mentioned to give a clearer picture of the process. The listed activities will be reported in tables together with their cycle times. An analysis will follow each packaging machine for whole groups or single activities, presented as bottle necks. The results will be analyzed and viewed from an efficiency perspective and will be compared to, among other things, the points Lean presents for waste. Here, the bottle necks will be described alongside why they are considered bottle necks for the packaging machines. In connection to this a probable reason and solution is presented. The result is expected to help the company grow and lay a foundation for future studies in related areas that will be further described in the conclusion.

In line with today's emergence of new technology, there is high competition within the manufacturing industry, which places higher demands on today's industries to develop new strategies to withstand the fierce competition. For this reason, today's industry needs to be more efficient and is becoming increasingly digitized, which is the core of the new industrial revolution called "industry 4.0".  The aim of this study is to investigate, with the help of value flow analysis, new innovative tools, and principles within lean production, whether the manufacturing process can be more efficient. The study was carried out at a manufacturing company that produces dehumidifiers and has ambitions to streamline it’s manufacturing process.  Through the literature review, site observations, interviews and data analysis, a comparison was made with the theory to find solutions to the problems that emerged. The results of this study show that it is theoretically possible to make a manufacturing process more efficient using these methods. It can be pointed out that one important study will be to test these solutions to see what results can be achieved. / I linje med dagens framväxt av ny teknik råder det hög konkurrens inom tillverkningsindustrin, vilket ställer högre krav på dagens industrier att utveckla nya strategier för att stå emot den hårda konkurrensen. Av den anledningen måste dagens industri bli mer effektiv och digitaliseras alltmer, vilket är kärnan i den nya industriella revolutionen som kallas "industri 4.0".  Syftet med denna studie är att med hjälp av värdeflödesanalys, nya innovativa verktyg och principer inom lean production undersöka om tillverkningsprocessen kan bli mer effektiv. Studien genomfördes på ett tillverkningsföretag som producerar avfuktare och som har ambitioner att effektivisera sin tillverkningsprocess.  Genom litteraturgenomgång, platsobservationer, intervjuer och dataanalys gjordes en jämförelse med teorin för att hitta lösningar på de problem som uppstod. Resultaten av denna studie visar att det är teoretiskt möjligt att effektivisera en tillverkningsprocess med hjälp av dessa metoder. Det kan påpekas att en viktig studie kommer att vara att testa dessa lösningar för att se vilka resultat som kan uppnås.

Introduction: In today's competitive environment, manufacturing companies need to find new strategies and tools to improve manufacturing efficiency and minimize waste. This study is about production efficiency in a window manufacturing company. Purpose: The purpose was to identify challenges and efficiencies in window assembly using time study and value stream mapping (VSM) methods. Another aim was to develop efficiency suggestions to eliminate or minimize non-value adding activities. Methods: Using time studies and VSM, the flow of the case company was mapped and analysed. To answer the research questions of this study, a qualitative case study was conducted at the case company. The data collection for this study was carried out through structured and semi-structured interviews and observations made at the three stations of the case company's arm flow to identify non-value adding activities. In addition, literature was collected in relevant areas.  Results: Observations and interviews conducted in the selected flow show that the case company works lean tools such as 5S and Just-In-Time (JIT). The result also demonstrates which activities are value adding for the whole process, it also shows necessary but nonvalue adding activities.  Conclusion: The findings of the study showed that value stream mapping and time studies in combination can improve the efficiency of production.  The conclusion has also showed that the following lessons can be learnt when working with time studies and VSM:   Combining time studies and VSM, planning time studies and communication when working with time studies / Introduktion: Idag råder hård konkurrens och företag inom tillverkningsindustrin måste därför utveckla nya strategier och verktyg för att effektivisera sin tillverkning och minimera slöserier. Denna studie handlar om effektivisering av produktion hos ett tillverkande företag inom fönstertillverkning.  Syfte: Syftet med studien var att med hjälp av metoderna tidsstudier och värdeflödesanalys (VFA) identifiera utmaningar och effektiviseringar vid montering av fönster. Ett annat syfte var att ta fram effektiviseringsförslag för att eliminera eller minst icke-värdeskapande aktiviteter.  Metod: Med hjälp av tidsstudier och VFA har fallföretagets karmflöde kartlagts och analyserats. För att besvara studiens frågeställningar har en kvalitativ fallstudie utförts hos fallföretaget. Datainsamlingen utfördes genom dels strukturerade, och-dels semistrukturerade intervjuer, samt egna observationer av tre stationer i fallföretagets karmflöde för att identifiera icke-värdeskapande aktiviteter. Dessutom har litteratur samlats in inom relevanta områden.  Resultat: Observationer och intervjuer som genomfördes i det valda flödet visar att fallföretaget arbetar med lean-verktyg som 5S och JIT. Resultatet visar också vilka aktiviteter som är värdeskapande för hela processen, samt också nödvändiga men icke värdeskapande aktiviteter.  Slutsatsen: Studiens slutsatser visade att tidsstudier och värdeflödesanalys i kombination kan effektivisera produktionen. Studiens slutsats har också visat att följande lärdomar kan dras vid arbetet med tidsstudier och VFA:  Kombination av tidsstudier och VFA planering av tidsstudier och kommunikation vid arbete med tidsstudier

I industriföretag används managementverktyg för att utveckla och effektivisera verksamheten så att ledtider och slöseri reduceras i samtliga processer. Parker PMDE Trollhättan tillverkar hydraulikmaskiner. Sedan 90-talet har Parker bedrivit verksamhetsutveckling enligt management principer i Lean Production. Ett nästa steg i Parkers ständiga förbättringsarbete var att undersöka möjligheter att utveckla en materialsatsningsavdelning så att en person kan förse monteringen med material tillräckligt snabbt utan att extra resurser behöver tillsättas. I dagsläget råder det obalans gentemot takttider i monteringen och det tar längre tid för satsningen att plocka ihop fyra satser än vad det tar för monteringen att förbruka dessa satser.Målet med examensarbetet var att ta fram förbättringsförslag där en person får förutsättningar att plocka ihop material till montering av fyra hydraulikmaskiner på mindre än 16 minuter. Delmålen var att göra en kartläggning av tider och arbetsmoment vid satsningen. Avgränsningarna i projektet var att inte undersöka processer utanför satsningen. Examensarbetet utformades efter DMAIC-metodiken, som är en projektmodell för faktabaserad problemlösning och tydlig struktur. Metoderna som användes vid insamling av data var observationer och analys av videoinspelat material som utfördes i programvaran AviX Method. Videoinspelningarna kategoriserades som olika aktiviteter i satsningsprocessen där gång, plock, scannertid, förmontering och övrig tid var de största kategorierna. Arbetsmoment identifierades som var tidskrävande och ej tillförde värde i processen. Mätningarna låg till grund för generering av lösningsförslagen.Baserat på ovanstående resultat och med hjälp av brainstorming genererades lösningsförslag tillsammans med produktionstekniker och materialhanterare. De lösningsförslag som uppfyllde målet med projektet att plocka en 4-sats under 16 minuter var pick by voice, pick by light, ringscanner och flytt av kilpress. Pick by voice anses vara lösningen som företaget bör införa eftersom den reducerar plocktid, scannertid och är ett flexibelt system. Ytterligare två lösningsförslag togs fram som inte uppfyllde målet men uppfattas som värda för företaget att utreda vidare utifrån Lean Production och ergonomiska skäl. De lösningsförslagen som inte uppfyllde målen bestod av en förändring av plockrundan och införande av en magnetlyft. / In industries, the management tools of Lean Production are used to develop and streamline operations in a way to reduce waste and lead times in all processes. Parker PMDE in Trollhättan manufactures hydraulic machines. Since the 90´s, Parker has pursued business development under the management principles of Lean Production. One of the next steps in Parkers continuous improvement was to explore opportunities to develop a kitting department so that a worker could provide the assembly with the material quickly without surplus resources. In the current situation, there is an imbalance from the kitting station towards the tact times in the assembly station because it takes longer at the kitting station to pick materials for four hydraulic machines, than it takes for the assembly station to consume these kits of materials.The aim of the thesis was to develop suggestions for improvement where a worker could perform the kitting process in less than 16 minutes. The interim objectives were to do a survey of the times and activities within the kitting process. The boundaries of the project was not to examine processes outside the kitting station. The project was designed according to DMAIC methodology, which is a project model for fact-based problem solving and clear structure. The methods used in the data collection were observation and analysis of video footage applying the software called AviX Method. Video recordings were categorized as different activities in the kitting process such as transport, picking, scanner time, pre-assembly and uncategorized time. Activities that were time consuming and did not add value to the process were identified. These data measures were the basis for the solution proposals.Based on these results and using brainstorming, solution proposals were generated together with the engineers and material handlers. The solution proposals that met the objective of the project of picking a 4-set of materials in 16 minutes were: Pick by voice, Pick-by-light, Ring Scanner and Relocation of one pre-assembly operation. Pick by voice is considered to be the most appropriate solution for the company since it reduces picking times, scanning times and is a flexible system. Two more proposed solutions were developed that did not meet the objective of the project, but are considered worth investigating further based on Lean Production and ergonomic reasons. These proposed solutions consisted of changing the picking route and the installation of a magnetic lift.

Kognitive Kontrolle wird besonders in solchen Momenten deutlich, wenn eine geplante Handlung gestört wird. Weil zwei widerstreitende Verhaltenstendenzen gleichzeitig bestehen oder anlaufen, entsteht ein Konflikt. Experimentell können kognitive Konflikte beispielsweise mit dem Stroop-Paradigma hergestellt und untersucht werden (Stroop, 1935). Es ist dabei eine aktuelle Frage, wie Konflikte zeitlich verarbeitet werden und wo im Gehirn diese Verarbeitung geschieht. Zeitlich können Konflikte beispielsweise dann entstehen, wenn die Informationen des Stimulus abgerufen werden oder auch erst dann, wenn die intendierte Antwort tatsächlich für die Artikulation ausgewählt werden muss. Eine weiterführende Frage ist, ob sich die entsprechenden Ergebnisse für verschiedene Stroop-Varianten unterscheiden. In der vorliegenden Arbeit wurden diese Fragen systematisch für die Verarbeitung von Objekten und Zahlen mit zwei Varianten des Stroop-Paradigmas untersucht. In der vorliegenden Dissertation präsentiere ich Ergebnisse von Reaktionszeitstudien und fMRT-Experimenten zum zeitlichen Ablauf und zu neuronalen Substraten kognitiver Konflikte während der Verarbeitung von Objekten und Zahlen. Um die Konflikte zeitlich und räumlich lokalisieren zu können, wird die Abrufphase und die Antwortphase separat modelliert. Die Ergebnisse deuten darauf hin, dass die Konflikte eher während des Abrufs als bei der Antwortauswahl stattfinden. Außerdem wird geschlussfolgert, dass die Konflikte für Zahl- und Objektrepräsentationen nicht auf gemeinsamen neuronalen Substraten basieren. Die Ergebnisse meiner Reaktionszeitstudien und der MRT-Studien deuten also darauf hin, dass Konflikte bei der Verarbeitung von Objekten und Zahlen zwar einem ähnlichen zeitlichen Verlauf folgen, aber offenbar in unterschiedlichen neuronalen Netzwerken verarbeitet werden. / In daily life, we constantly have to adjust our goals and plans to changing task demands and internal needs. Our ability to balance the initiation and inhibition of our actions, and to solve resulting conflicts between them, is referred to as cognitive control. To study the processes of cognitive control, the Stroop Paradigm has become a popular tool (Stroop,1935). The Stroop Paradigm is frequently used to address central questions of cognitive control. It is, for instance, an open issue, where and when in the processing stream cognitive conflicts arise. Do they arise early, for example, during the retrieval of target and distractor? Or do they occur late, when the response is prepared for execution? Another debate is concerned with the question whether the findings agree for different Stroop variants (Van Maanen et al., 2009). In this dissertation I present research on the temporal characteristics and the neural substrates of cognitive conflicts during the processing of objects and numbers. To better understand the locus of the conflict, the retrieval phase and the response phase are modelled separately. The results from several reaction time studies and from two fMRI experiments speak to the issue that processing costs occur during retrieval, i.e., early in the processing stream, for both, object and number representations. The results further indicate that the processing of the conflict between target and distractor for number and object representations do not rely on common neural substrates. I will thus present the results from behavioural and functional imaging experiments, showing similar temporal patterns for the conflicts in both systems, but distinct underlying neural networks.