This dissertation focuses on the use of subcarrier multiplexing (SCM) in multimode fibers, utilizing carrier frequencies above what is generally utilized for multimode fiber transmission, to achieve high bit rates. In the high frequency region (i.e., frequencies larger than the intermodal bandwidth), the magnitude response of multimode fiber does not decrease monotonically as a function of the frequency but is shown to become relatively flat (but with several deep nulls) with an amplitude below that at DC. The statistical properties of this frequency response at high frequencies are analyzed. The probability density function of the magnitude response at high frequencies is found to be a Rayleigh density function. The average amplitude in this high frequency region does not depend on the frequency but depends on the number of modes supported by the fiber. To transmit a high bit rate signal over the multimode fiber, subcarrier multiplexing is adopted. The performance of the SCM multimode fiber system is presented. The performance of the SCM system is significantly degraded if there are some subcarriers located at the deep nulls of the fiber. Equalization and spread spectrum techniques are investigated but are shown to be not effective in combating the effects of these nulls. To cancel the effects of these deep nulls, training process and diversity coding are considered. The basic theory of diversity coding is given. It is found that the performances of the system with training process and the system with diversity coding are almost identical. However, diversity coding is more appropriate since it requires less system complexity. Finally, the practical limits and capacity of the SCM multimode fiber system are investigated. It is shown that a signal with a bit rate of 1.45 Gbps can be transmitted over a distance up to 5 km. / Ph. D.

Betong är världens mest använda byggnadsmaterial och en stor utsläppskälla av koldioxid. Det är framför allt produktion av cementet i betongen som bidrar till koldioxidutsläppen. Globalt sett är produktionen av cement den tredje största orsaken till koldioxidutsläpp, 8 % av världens utsläpp. Därför ligger det stort intresse i att minska mängden cement i betongen för att nå lägre klimatpåverkan. Ett sätt att göra detta på är att delvis byta ut cementet mot andra tillsatsmaterial med cementliknande egenskaper, till exempel slagg. Det största problemet med detta är att betongens härdningstid förlängs. Detta arbete genomförs tillsammans med RISE för att hjälpa Hedareds Sand och Betong att ställa om till klimatförbättrad betong i sina prefabelement. För att göra detta måste härdningstiden i den klimatförbättrade betongen sänkas. Denna studie ska därför undersöka om accelererande tillsatsmedel kan korta härdningstiden i slaggbetong. För att undersöka detta användes två experimentella metoder: isotermisk kalorimetri och gjutning med tryckprovning. Resultatet från den isotermiska kalorimetrin visade att acceleratorn Master X-Seed 140 gav kortast induktionsperiod och klart högre värmeflöde än referensprovet. Resultatet från gjutningen visade att den prövade betongen nådde en tryckhållfasthet på 29,73 MPa efter 24 timmar. Vilket är 62,5 % högre än referensprovet utan accelerator och tydligt över kravet på 16 MPa efter 24 timmar. Slutsatsen som gick att dra efter detta arbete var att acceleratorn visade mycket god effekt på tryckhållfastheten och ger utökade möjligheter att använda klimatförbättrad betong inom prefabindustrin. / Concrete is the world's most widely used building material and a significant source of carbon dioxide emissions. It is primarily the production of cement in concrete that contributes to these emissions. Globally, cement production is the third-largest contributor to carbon dioxide emissions, accounting for 8 % of the world's emissions. Therefore, there is considerable interest in reducing the amount of cement in concrete to achieve lower climate impact. One way to do this is by partially replacing cement with other supplementary materials with cement-like properties, such as slag. The main challenge with this approach is that it extends the curing time of the concrete. This work is conducted in collaboration with RISE to assist Hedareds Sand and Betong in transitioning to climate-enhanced concrete in their precast elements. To achieve this, the curing time in the climate-enhanced concrete must be reduced. This study aims to investigate whether accelerating admixtures can shorten the curing time in slag concrete. Two experimental methods were used to investigate this: isothermal calorimetry and casting with pressure testing. The results from isothermal calorimetry showed that the accelerator Master X-Seed 140 had the shortest induction period and significantly higher heat flow than the reference sample. The results from casting showed that the tested concrete reached a compressive strength of 29,73 MPa after 24 hours, which is 62,5 % higher than the reference sample without accelerator and clearly exceeds the requirement of 16 MPa after 24 hours. The conclusion drawn from this work was that the accelerator demonstrated a very good effect on compressive strength and provides expanded opportunities for using climate-enhanced concrete in the precast industry.

Declining fertility rates are an increasingly important topic in today’s Europe. Fertility rates play a significant role in sustaining a stable population and ensuring economic growth and innovation. The purpose of this thesis is to evaluate the effectiveness of CSOK, a Hungarian housing policy specifically aimed at increasing fertility rates. The research relies on theories such as Becker’s new home economics theory, Quantity-quality trade-off theory, and Willis’s economic theory of family. The study of housing prices and fertility is also provided to understand the relationship between housing and fertility better. The benchmark country for this thesis is Hungary. Using the Synthetic Control Method (SCM), we construct a synthetic Hungary to match pretreatment outcomes closely. The findings of this thesis show that the policy has no positive effect on fertility rates and is inefficient in spending government resources. The study highlights the significance of governmental trust, emphasizing the importance of stable economic conditions and a family-friendly environment to effectively increase fertility rates.

A gerência de configuração vem sendo estudada desde os anos sessenta. Inicialmente, era aplicada da mesma forma para software e hardware, sendo que no final dos anos setenta já havia padrões de gerência de configuração específicos para software. Com a crescente demanda por qualidade de software, as práticas de gerência de configuração vem sendo cada vez mais utilizadas no desenvolvimento de software, uma vez que a gerência de configuração de software é um dos processos fundamentais para se ter qualidade no desenvolvimento e manutenção de software. Embora cada vez mais amplamente utilizado, não existe um consenso de práticas e nomenclaturas sobre as práticas de gerência de configuração. Dessa forma, o objetivo deste trabalho é elaborar um modelo de avaliação do processo de Gerência de Configuração, que permite avaliar as práticas e processos fundamentais para a implantação da gerência de configuração, levando em consideração as práticas e processos descritos nas principais normas internacionais de desenvolvimento de software. Esse modelo de avaliação também permite que as ferramentas disponíveis para gerência de configuração sejam avaliadas, identificando quais práticas e processos elas auxiliam na execução. / The Configuration Management has been studied since the 70’s. In the beginning it was applied in the same way for software and hardware, but in the late 70’s there were some specific configuration management patterns defined for software. The demand for software quality has increased recently, this way the configuration management practices have been more used in software development, because the software configuration management is one of the most important processes to assess quality during software development or maintenance. Although its use is increasing, there is no consensus about the configuration management practices and the names applied to them. The objective of this work is to elaborate an evaluation model for configuration management process, to evaluate the practices and the fundamental processes to perform configuration management, based on the most important software development standards. This evaluation model can also be used to evaluate configuration management tools, identifying what practices and process it help to execute.

A gerência de configuração vem sendo estudada desde os anos sessenta. Inicialmente, era aplicada da mesma forma para software e hardware, sendo que no final dos anos setenta já havia padrões de gerência de configuração específicos para software. Com a crescente demanda por qualidade de software, as práticas de gerência de configuração vem sendo cada vez mais utilizadas no desenvolvimento de software, uma vez que a gerência de configuração de software é um dos processos fundamentais para se ter qualidade no desenvolvimento e manutenção de software. Embora cada vez mais amplamente utilizado, não existe um consenso de práticas e nomenclaturas sobre as práticas de gerência de configuração. Dessa forma, o objetivo deste trabalho é elaborar um modelo de avaliação do processo de Gerência de Configuração, que permite avaliar as práticas e processos fundamentais para a implantação da gerência de configuração, levando em consideração as práticas e processos descritos nas principais normas internacionais de desenvolvimento de software. Esse modelo de avaliação também permite que as ferramentas disponíveis para gerência de configuração sejam avaliadas, identificando quais práticas e processos elas auxiliam na execução. / The Configuration Management has been studied since the 70’s. In the beginning it was applied in the same way for software and hardware, but in the late 70’s there were some specific configuration management patterns defined for software. The demand for software quality has increased recently, this way the configuration management practices have been more used in software development, because the software configuration management is one of the most important processes to assess quality during software development or maintenance. Although its use is increasing, there is no consensus about the configuration management practices and the names applied to them. The objective of this work is to elaborate an evaluation model for configuration management process, to evaluate the practices and the fundamental processes to perform configuration management, based on the most important software development standards. This evaluation model can also be used to evaluate configuration management tools, identifying what practices and process it help to execute.

<p>Denna rapport syftar till att, på Å&R Carton i Norrköping, analysera de interna flödena och processerna samt ge förslag på hur ledtider ska kunna reduceras väsentligt. Ett sätt att uppfylla syftet är att dela in verksamheten i processer genom olika metoder och kriterier förprocessbestämning. Valda metoder i rapporten är; kvalitativ ansats med hög validitet och reliabilitet, processbaserad verksamhetsanalys och procedurbeskrivning. </p><p>Genom omfattande litteraturstudier, insamlande av data i form av intervjuer, benchmarking, platsundersökningar och interna dokument har nulägesmodeller arbetats fram. Analysen av dessa visar bland annat på att såväl planeringsprocessen som inköpsprocessen idag inte fungerar värdeadderande och bör ses över. Därutöver finns också andra processer som bidrar till ett komplext flöde. Dessa behöver effektiviseras eller ändras för att korta ledtider. Vidare visar analysen på att en omfattande attitydsundersökning behövs, dels för att komma till rätta med vissa stämningar och dels för att på sikt skapa en effektiv arbetsmiljö. </p><p>Till förbättringsförslagen hör, förutom en attitydsundersökning, förslaget att utarbeta tydliga mål och strategier. Sedan måste dessa kommuniceras till samtliga anställda, till exempel genom arbetsgrupper. Vidare föreslås att Å&R Carton tittar på automatisk datafångst som ett mycket kostnadseffektivt sätt att kontrollera det totala flödet. På lång sikt bör också företaget titta på att implementera processorientering. Dock behöver företaget först och främst se till att skapa en förändringsvillig attityd för att nå framgång i sitt effektiviseringsarbete. Slutsatsen blir att Å&R Carton har stor potential att väsentligt förkorta sina ledtider om företaget hanterar situationen rätt. För att lyckas kan delar av denna rapport användas där det viktigaste är att en engagerad ledning visar vägen. </p> / <p>The purpose of this final thesis is to analyse the internal processes at Å&R Carton in Norrköping and give proposals to reduce time in the Supply Chain. One way to fulfill the purpose is to use Process Based Analys and split the organisation in different processes. Process Based Models have then been constructed by studying litterature, benchmarking, internal documents and making a lot of interviews. The analys shows that different processes must be changed to make the flow through the Supply Chain more efficient. The analys give us also recommendations like attitude investigations and implementation of ECR. The conclusion is that Å&R Carton have great potential to reduce time in the Supply Chain if the management are active, follow the recommendations and show the employees the way about.</p>

Denna rapport syftar till att, på Å&amp;R Carton i Norrköping, analysera de interna flödena och processerna samt ge förslag på hur ledtider ska kunna reduceras väsentligt. Ett sätt att uppfylla syftet är att dela in verksamheten i processer genom olika metoder och kriterier förprocessbestämning. Valda metoder i rapporten är; kvalitativ ansats med hög validitet och reliabilitet, processbaserad verksamhetsanalys och procedurbeskrivning. Genom omfattande litteraturstudier, insamlande av data i form av intervjuer, benchmarking, platsundersökningar och interna dokument har nulägesmodeller arbetats fram. Analysen av dessa visar bland annat på att såväl planeringsprocessen som inköpsprocessen idag inte fungerar värdeadderande och bör ses över. Därutöver finns också andra processer som bidrar till ett komplext flöde. Dessa behöver effektiviseras eller ändras för att korta ledtider. Vidare visar analysen på att en omfattande attitydsundersökning behövs, dels för att komma till rätta med vissa stämningar och dels för att på sikt skapa en effektiv arbetsmiljö. Till förbättringsförslagen hör, förutom en attitydsundersökning, förslaget att utarbeta tydliga mål och strategier. Sedan måste dessa kommuniceras till samtliga anställda, till exempel genom arbetsgrupper. Vidare föreslås att Å&amp;R Carton tittar på automatisk datafångst som ett mycket kostnadseffektivt sätt att kontrollera det totala flödet. På lång sikt bör också företaget titta på att implementera processorientering. Dock behöver företaget först och främst se till att skapa en förändringsvillig attityd för att nå framgång i sitt effektiviseringsarbete. Slutsatsen blir att Å&amp;R Carton har stor potential att väsentligt förkorta sina ledtider om företaget hanterar situationen rätt. För att lyckas kan delar av denna rapport användas där det viktigaste är att en engagerad ledning visar vägen. / The purpose of this final thesis is to analyse the internal processes at Å&amp;R Carton in Norrköping and give proposals to reduce time in the Supply Chain. One way to fulfill the purpose is to use Process Based Analys and split the organisation in different processes. Process Based Models have then been constructed by studying litterature, benchmarking, internal documents and making a lot of interviews. The analys shows that different processes must be changed to make the flow through the Supply Chain more efficient. The analys give us also recommendations like attitude investigations and implementation of ECR. The conclusion is that Å&amp;R Carton have great potential to reduce time in the Supply Chain if the management are active, follow the recommendations and show the employees the way about.

Taiwan steel industry has stepped from grown-up into mature period. Especially, the midstream and downstream of steel industries will face the problems of sterner challenges and overcapacity, because of the oversupply of global steel. Not only the prices of oil, coal, water and power have climbed, but also the shipping cost has increased continuously. The improvement of Supply-Chain-Management (SCM) has become a significant issue under the circumstances. The SCM of Taiwan flat cold-rolled steel industry is different from the other ones that it doesn¡¦t use BOM. The main feature of Technical System ¡V ¡§Standard of Operation¡¨(SOP) is the kernel module that links the sales order entry, production management, purchasing, ¡Ketc. The production type is to input a sole coil and output many sub-coils. It is not like the electronic industry to assemble many parts on a product. It only coats the surface of steel with microelements, such as oil, zinc, aluminum and paint. The feature makes it impossible to apply SCM or ERP package directly on this industry. The procedures of this study are mainly through the interview of steel companies, and review on the relevant reference documents related to the subject of those have been published domestically and internationally, meanwhile to get a better understanding on the most recent development of Supply Chain Management and e-business of steel industry. Besides, through the comparison of the similar companies, it is likely to understand the associated topics and models on the SCM and e-Business for flat cold-rolled steel industry. The key point is to analyze the characters of supply chain system of Taiwan cold-rolled steel industry and consider the features of flat cold-rolled steel ¡V SOP and coil- based Standard Cost system, to establish an appropriate e-SCM model, exploring the suitable information technologies and applications to improve the drawbacks of present SCM. Finally, to make a recommendation for the industry as their reference when they plan for the implementation of e-SCM.

La recherche souligne, selon une perspective béhavioriste, l’importance grandissante de l’intermédiation logistique à travers le rôle dynamisant du PSL au sein des chaînes logistiques multi-acteurs. En s’éloignant de son métier historique, en l’occurrence la gestion de simples acheminements, le PSL évolue vers des services à plus forte valeur ajoutée, voire de nouveaux métiers, qui transforment en profondeur le fonctionnement de ces chaînes. S’inscrivant dans une logique d’exploration, la recherche participe à enrichir les travaux antérieurs relatifs au PSL, souvent de nature technique, par une approche béhavioriste. Le PSL est d’abord un acteur, doté d’objectifs propres, qui développe un comportement stratégique singulier ; il ne se résume pas à être un simple exécutant opérationnel d’activités issues d’une externalisation voulue par des chargeurs à la recherche d’une minimisation des coûts. Une telle approche, jusque-là peu explorée, permet de mieux saisir le rôle dynamisant du PSL dans les chaînes logistiques multi-acteurs, tout particulièrement dans le contexte français. Il ressort de la recherche que le PSL a acquis un pouvoir suffisant pour en influencer le fonctionnement. Il occupe une position de choix pour capter durablement de la valeur, autrement dit, bénéficier de transfert d’activités, de compétences et de ressources de la part des chargeurs. / The goal of our research is to underline, from a behavioral angle, the increasing importance of logistical intermediation through the LSP’s dynamic role within supply chains. By digressing from its historical profession, the management of simple carriages to be specific, the LSP is moving towards high added value services, even new trades, which deeply transform the chains’ functioning. By falling within an exploratory logic, this research participates in enriching the previous works about LSP, mainly of a technical nature, through a behavioral approach. At first, the LSP is an actor which has his own goals and who develops a singular strategic behavior: it does not amount to be a simple operational performer of activities coming from an outsourcing required by shippers in search of a minimization of the costs. Such an approach, which has not been explored so far, enables a better understanding of the dynamic role of the LSP in supply chains, particularly in the French context. It comes out of the research that the LSP has acquired enough power to influence its functioning. It is rightly placed to get some value durably, in other words, to benefit from transfer of activities, skills and resources from the shippers.

Ce mémoire de thèse traite de la caractérisation de microfils et nanofils semi conducteurs dopés individuels par microscopie à émission de photoélectrons X (XPEEM) complétée par des techniques de champ proche électrique: Kelvin force microscopy (KFM) et scanning capacitance microscopy (SCM). L'objectif est d'évaluer l'apport des méthodes locales de surface « sans contact », grâce à la mesure du travail de sortie local et de l'énergie de liaison des niveaux de cœur, pour l'étude des phénomènes liés au dopage dans ces objets, comme par exemple l'uniformité longitudinale. Nous mettons d'abord en évidence l'importance de la préparation des échantillons pour la mise en œuvre des techniques citées: méthodes de transfert des fils, adéquation du substrat, influence des caractérisations pré-analyse. Nous présentons ensuite deux principales études de cas en lien avec une problématique technologique : les microfils de nitrure de gallium dopés Si (diamètre 2 µm) pour applications dans l'éclairage à l'état solide, et les jonctions pn à nanofils de Si (diamètre 100 nm) pour la nanoélectronique basse puissance. Dans le premier cas, nous avons mis en œuvre la SCM pour l'identification rapide de l'hétérogénéité axiale du dopage n, puis avons utilisé l'imagerie XPEEM spectroscopique avec excitation synchrotron pour, d'abord, estimer le travail de sortie local et la courbure de bande en surface; ensuite, élucider les modes d'incorporation du silicium en surface, qui pointent notamment sur la sensibilité des conditions d'élaboration dans la part du dopage intentionnel (Si en sites Ga) et non intentionnel (Si sur sites lacunaires en azote). (Des mesures complémentaires sur sections radiales et longitudinales de fils, par microscopie Auger et spectrométrie ToF-SIMS montrent une incorporation du Si limitée à la surface des microfils). Concernant les jonctions pn à nanofils de silicium étudiées après retrait partiel de l'oxyde de surface, nous avons mis en relation des résultats obtenus indépendamment par KFM et par XPEEM. Ils mettent conjointement en lumière une très faible différence de travail de sortie local entre partie n et partie p, et qui semble en partie expliquée par un ancrage du niveau de Fermi en surface. / This thesis addresses the characterization of individual doped semiconductors microand nanowires by photoemission electron microscopy (XPEEM) and near field techniques : Kelvin probe force microscopy (KFM) and scanning capacitance microscopy. The aim of this study is to evaluate the benefits of contactless surface methods, thanks to local work function and core level binding energy measurements, for the study of phenomena linked to doping in such objects, like for example axial uniformity. First, we highlight the importance of sample preparation required for these techniques: wires transfer methods, substrate/wire match, and preanalysis characterization influence. Then we present two case studies addressing technological issues: Si doped gallium nitride microwires (2μm diameter) for solid state lighting, and p-n junction nanowires (100 nm diameter) for low power microelectronics. In the first case, we have performed SCM for quick identification of n doping axial heterogeneity, then performed spectroscopic XPEEM using synchrotron radiation to, first, estimate local work function and surface band bending, then clarify surface silicon incorporation highlighting growth process influence over intentional (si on Ga sites) and unintentional doping (si on nitrogen vacancy). Complementary measurements on both axial and radial section of wires have been led by Auger microscopy and ToF-SIMS, highlighting silicon incorporation preferentially at the surface of the microwires. Regarding p-n junctions, after partial removal of surface oxide, we have linked results obtained independently by KFM and XPEEM. Both methods highlighted a weak local work function difference between n-doped and p-doped part, partly explained by Fermi level pinning induced by surface states.