A constant research of more ecological and efficient structures has enabled bridges to be more innovative through the years. Nowadays, as the need is greater than ever, a new kind of bridge is expanding in the entire world: the network arch bridges. The concept was developed by professor and engineer Per Tveit in 1955 and has been improved since then. But it is only for 10 years that many bridges of this sort have been built. The aim of the thesis is to investigate the structural behavior of these bridges and their efficiency comparing to traditional bridges. It is also proving the efficiency of the network arches used for rail traffic. To do so, a single-track railway network arch has been designed according to the Eurocodes. A 2D model has been designed to be optimal and tested under Abaqus for the loads defined in the Eurocodes. Guidelines from the literature and Per Tveit’s work have been used to determine the optimal geometry of the bridge. The steel weight needed for the 75 meters long bridge is assessed from the final design and is the main parameter to compare and evaluate the network arch structural efficiency. These results are compared with Tveit’s statements and with other structures.

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In dieser Dissertation untersuche ich verschiedene Aspekte des Integrationsprozesses von Migranten und Flüchtlingen, insbesondere wie sich ihre Präsenz auf die Protestaktivitäten und Einstellungen von Einheimischen auswirkt. Die vier Kapitel bauen auf der bestehenden Literatur auf und zielen darauf ab, diese in mehreren Aspekten zu ergänzen. Das erste und das zweite Kapitel verbessern unser Verständnis der kausalen Auswirkungen der Bedingungen im Heimatland auf die Rückkehrabsichten und die Arbeitsmarktintegration von Migranten im Zielland sowie das Verständnis der Auswirkungen traumatischer Erfahrungen während der Flucht auf die Arbeitsmarktintegration von Flüchtlingen. Das dritte Kapitel befasst sich mit der soziokulturellen Integration von Familienmigranten in einem Land, das nicht ihre erste Wahl darstellt. Das vierte Kapitel untersucht die Auswirkungen der Anwesenheit von Ausländern auf die Protestaktivität einer bestimmten Gruppe von Einheimischen und wie sich diese Proteste auf die Besorgnis über Fremdenfeindlichkeit und Intoleranz auf nationaler Ebene auswirken. Die Ergebnisse der Dissertation sollen die politischen Entscheidungsträger über die potenziellen Nebenwirkungen der Migrationspolitik informieren und empirische Erkenntnisse liefern, die zur Verbesserung bestehender und zur besseren Gestaltung künftiger politischer Maßnahmen beitragen. / In this PhD thesis, I look at different aspects of the integration process of migrants and refugees, and how their presence affects the protest activity and attitudes of natives. The four chapters build on and aim to extend the existing literature along several dimensions. The first and second chapters improve our understanding of the causal effect of home country conditions on migrants' return intentions and labour market outcomes at destination and of the effect of traumatizing experiences along the journey on refugees' labour market integration. The third chapter explores the socio-cultural integration of family migrants in a country that was not their primary choice, while the fourth chapter examines the effect of the presence of foreigners on the protest activity of a particular group of natives and how these protests affect worries about xenophobia and intolerance at the national level. The findings in the dissertation aim to inform policymakers on the potential side-effect of migration policies and to provide empirical evidence that help improve existing policies and better design future ones.eral dimensions.

Mossberg (1998) bekräftar att batch-baserad logstik inom bokbranschen har flertalet negativa konsekvenser. Mossberg (1998) skriver följande; ”ETT PÅGÅENDE RESURSSLÖSERI De osålda böckerna drar på sig transport- och lagerkostnader… …överskottet -- inte sällan mer än halva upplagan! -- makuleras inom en treårsperiod. Bortsett från det stötande i detta resursslöseri bidrar förfarandet till att den svenska bokmarknaden har fått den ’’färskvaruprägel’’ som tidigare berörts -- och som innebär en tidsmässig begränsning av den svenskspråkiga litteraturen.” (Mossberg, 1998)  Mossbergs (1998) iakttagelser stödjer även de observationer vi gjort på fallföretaget. Detta är också grunden till vårt projekt där vi bidrar till ett mera effektivt och hållbart arbetssätt hos en av Sveriges största ekonomiboksproducenter. Syftet med denna studie är att undersöka vilka fördelar som enligt teorin kan uppnås vid en övergång från en batch-baserad till en print-on-demand baserad logistikhantering av böcker.    Målet är att presentera rekommendationer för beslutsfattande och framtida strategi för fallföretaget, men också för att hjälpa andra företag med liknande krav och behov. Denna fallstudie genomförs på ett svenskt företag där man i huvudsak arbetar med kundservice/support till företag som använder sig av deras bokföringsprogram och servicetjänster. En viktig del i deras tjänst innebär publicering samt e-försäljning av informationsböcker. Vi har dock kunnat se att ytterst lite görs för att förbättra sin kvalitet inom detta område.  Vår undersökning visar att fallföretaget sammantaget skulle vinna flera fördelar genom att använda sig utav en print-on-demand-lösning. Detta eftersom man skulle förbättra sin kvalitet i alla de avseenden vi fokuserat på, med en lägre totalkostnad, ingen kapitalbindning och en minskad påverkan på miljön. / Mossberg (1998) confirms that batch-based logistics in the book industry has several negative consequences. Mossberg (1998) writes the following;  "AN ONGOING WASTE OF RESOURCES The unsold books are incurring transportation and inventory costs ... ... surplus - often more than half the recipients edition! -- canceled within three years. Aside from the offensive in this waste of resources, this procedure contributes to the fact that the Swedish book market has got the '' fresh character '' as mentioned earlier -- and as entails a temporal limitation of the Swedish-language literature" (Mossberg, 1998)  Mossberg's (1998) findings also support the observations we have made in this study. This constitutes the foundation of this survey, where we contributes for a more effective and sustainable operation at one of Sweden's largest economy book producers.  The purpose of this study is to examine the advantages and disadvantages that come with make-to-stock and a batch based logistics management of books. But also to identify the advantages that, according to the theory, can be achieved in a transition to make-to-order with a print-on-demand solution.   The goal is to present recommendations for decision-making and future strategy for the company where this study took place, as well as to help other companies with similar needs and requirements.  This case study is conducted at a Swedish company which essentially work with customer service / support to businesses using their accounting software and services. An important part of their service means publishing as well as e-books sale of information books. We have noticed that little is done to improve their efficiency and quality in this area.  Our study shows that this company would gain several benefits by making use out of a print-on-demand solution. This because it would improve their quality in all respects we’ve focused on, with a lower total cost, no tied up capital and en reduced environmental impact.

Spare parts are, for many companies, a complex product to logistically handle. This is in part due to the varying characteristics and sporadic demand patterns of spare parts. Obstacles can often arise when companies utilize the same approach to their spare parts stock as they do with their general warehouse manufacturing inventory. By using the same approach, companies risk neglecting the widespread variation of the spare parts. With the help of established routines, a clear set of guidelines and factors, the chances of a successful handling of spare parts inventory is increased. The study is a qualitative case study with the purpose of identifying specific factors and to make recommendations of models for companies to take into account when evaluating and storing spare parts. Through unstructured/semi-structured interviews conducted with four case company employees, information was gathered which was used to assist in identifying these specific factors and models for companies. A theoretical frame of reference was produced through analyzing research articles and was compared to the compiled empirical data in an analysis. The departments within the case study based their work on single factor which were considered important for each specific department, without inter-departmental communication. The factors that were identified in the study include service, competitive advantage, tied up capital, size capacity, complexity, sales frequency and material. Four of these were considered to be a priority for the case company. The study showed that different models for spare parts management and outsourcing could be implemented in the case company. By integrating the different models for spare parts management and outsourcing, combined with communication, a new model has been proposed for handling the spare parts storage. / Reservdelar är för många företag en komplex produkt att hantera utifrån dess varierande egenskaper och sporadiska efterfrågemönster. Problematiken härstammar ofta från att många företag hanterar reservdelslager utifrån samma förutsättningar som dess allmänna lagerhantering, därigenom försummas reservdelarnas olika egenskaper. Förutbestämda riktlinjer och faktorer krävs vid hantering av reservdelar och en viktig komponent för att lyckas med detta är kommunikation. Arbetet är en kvalitativ fallstudie med syftet att ta fram faktorer och rekommendationer av modeller att ta hänsyn till vid värdering och lagerhantering av reservdelar. För att besvara syftet och frågeställningarna utfördes ostrukturerade/semistrukturerade intervjuer med fyra medarbetare på fallföretaget. En teoretisk referensram togs fram genom litteratursökningar som sedan ställdes i en jämförelse mot den sammanställda empirin i en analys. Studien visade att de olika avdelningarna på fallföretaget främst utgått från en enda faktor som ansetts vara viktig för den specifika avdelningen. Utifrån de framtagna faktorerna i studien; service, konkurrensfördel, kapitalbindning, fyllnadsgrad, komplexitet, försäljningsfrekvens och material, ansågs fyra av dessa vara av prioritet för fallföretaget. Studien visade att olika modeller för reservdelshantering och outsourcing skulle kunna implementeras på fallföretaget. Genom att integrera de olika modellerna för reservdelshantering och outsourcing, kombinerat med kommunikation, har en ny modell föreslagits för hantering av reservdelslager.

[pt] A necessidade da execução de escavações urbanas cada vez mais profundas tem imposto aos engenheiros geotécnicos o grande desafio de equilibrar elevados esforços horizontais com um mínimo de deslocamentos do maciço de solo e das estruturas localizadas nas vizinhanças. Para muitos destes casos, a utilização de cortinas atirantadas se constitui na solução técnica mais adequada. As primeiras obras com ancoragem em solo surgiram em diversos países (Alemanha, Itália, França) no final da década de 1950, numa evolução direta da técnica de ancoragem em maciços de rocha, e no Brasil esta técnica foi pela primeira vez empregada no Rio de Janeiro em 1957 nas rodovias Rio - Teresópolis e Grajaú - Jacarepaguá. Um grande avanço ocorreu na década de 1970, na implantação das obras do metrô de São Paulo, com a introdução de ancoragens reinjetáveis com calda de cimento sob altas pressões. Atualmente, ancoragens em solo são executadas intensamente em muitos países com cargas que em geral ainda não ultrapassam a 1500 kN. Esta dissertação tem como objetivo principal o estudo do comportamento de cortinas ancoradas em solo, incluindo uma revisão dos principais métodos para análises de estabilidade e obtenção da capacidade de carga. A utilização do método dos elementos finitos, através do programa comercial Plaxis v.7.2, permitiu a comparação dos valores do fator de segurança calculados com métodos de equilíbrio limite, bem como a realização de estudos paramétricos com o objetivo de verificar a influência no comportamento mecânico da cortina de vários parâmetros de projeto, tais como a espessura da cortina, ângulo de inclinação dos tirantes, embutimento da estrutura, etc. / [en] The need for deeper urban excavations has imposed to geotechnical engineers the great challenge of balancing high horizontal forces with occurrence of minimum displacements in soil as well as in the structures nearby. In many of such cases, tied-back earth retaining walls are the technical solution the most recommended. The use of ground anchorage, as a direct extension of the rock anchoring technique, began in several countries (Germany, Italy, France) during the decade of 1950. In Brazil, the first application occurred in the construction of the Rio - Teresópolis and Grajaú - Jacarepaguá highways in the State of Rio de Janeiro, in 1957, and it experimented an important development during excavation of galleries for the Sao Paulo subway, in the decade of 1970, where high pressure grouting has been firstly applied as an industrial process. Currently, soil anchorages are intensely executed throughout the world, carrying loads that in general are not higher than 1500 kN yet. This main objective of this thesis is to study the mechanical behavior of tied-back earth retaining walls, including a comprehensive review on the main methods used for stability analyses and load capacity calculation. The finite element method, through the commercial software Plaxis v.7.2, is employed in order to compare the values obtained for the safety factors through several techniques, as well as to carry out a parametric study to better understand the influence on the retaining wall of several engineering parameters such as the wall thickness, angle and number of ties, depth of wall embedment, etc.

A photo-voltaic system consists of solar cells, power converters, battery and the load. The power converter interfaces the solar cells, battery and the load. The battery serves to equalise the energy demand (load) and the energy supply (solar cell). Currently the solar cells and the battery cost nearly 90% of the system cost. A typical photo-voltaic system can adopt various power bus configurations. Battery tied bus is the simplest of the power bus configurations. In this topology, the battery is always attached to the bus. This system is extremely simple in terms of power circuit configuration as well as control. Such systems weigh less and are more reliable. However, the battery tied bus suffers certain disadvantages. The first among them is the poor utilisation of solar panels. The load has to tolerate the full swing of the battery voltage variation. On account of the constraint on the solar panel voltage, the solar panels may not be loaded to the maximum power capacity. Such operating conditions lead to gross under-utilisation of the expensive solar panels. The battery tied bus configuration is designed, built and evaluated experimentally with 4 solar panels rated at 35 W each and a lead acid battery of 12 V 42 AH rating. This thesis explores alternate power architecture to overcome the above limitations. Load regulation and maximum power harvesting from the solar panels are the objectives. In the proposed configuration, a bidirectional power converter is inserted between the bus and the battery. The bidirectional power converter operates in boost mode and charges the battery when the sunlight is available. During eclipse period, it operates in buck mode and meets the load demand. The maximum power is extracted from the panels by controlling the voltage across the solar panels. The bus voltage reference is computed by MPPT block and the bus voltage is regulated to the reference voltage through closed loop control. So the maximum power is extracted from the panels at the expense of extra bidirectional power converter. Even though there is an additional power loss due to the introduction of power converter, this power bus configuration is superior because it increases the output power from the panel itself. The entire control logic implementation is done digitally using dspic30F6010A. The simulation is done by writing script files in C language. The proposed bus configuration is designed, built and evaluated experimentally with the same setup and the results are then compared.

Made available in DSpace on 2014-12-17T14:48:12Z (GMT). No. of bitstreams: 1 JohnGBG_DISSERT.pdf: 5632038 bytes, checksum: eabbd6743af14f648742650469c3d48f (MD5) Previous issue date: 2012-07-02 / A numerical study on the behavior of tied-back retaining walls in sand, using the finite element method (FEM) is presented. The analyses were performed using the software Plaxis 2D, and were focused on the development of horizontal displacements, horizontal stresses, shear forces and bending moments in the structure during the construction process. Emphasis was placed on the evaluation of wall embedment, tie-back horizontal spacing, wall thickness, and free anchor length on wall behavior. A representative soil profile of a specific region at the City of Natal, Brazil, was used in the numerical analyses. New facilities built on this region often include retaining structures of the same type studied herein. Soil behavior was modeled using the Mohr-Coulomb constitutive model, whereas the structural elements were modeled using the linear elastic model. Shear strength parameters of the soil layers were obtained from direct shear test results conducted with samples collected at the studied site. Deformation parameters were obtained from empirical correlations from SPT test results carried out on the studied site. The results of the numerical analyses revealed that the effect of wall embedment on the investigated parameters is virtually negligible. Conversely, the tie-back horizontal spacing plays an important role on the investigated parameters. The results also demonstrated that the wall thickness significantly affects the wall horizontal displacements, and the shear forces and bending moments within the retaining structure. However, wall thickness was not found to influence horizontal stresses in the structure / O presente trabalho apresenta um estudo num?rico atrav?s do m?todo dos elementos finitos (MEF) utilizando-se o aplicativo computacional Plaxis 2D, com o objetivo de verificar aspectos do comportamento de estruturas de conten??o atirantadas em areia. As an?lises foram dirigidas ao desenvolvimento dos deslocamentos horizontais, das tens?es horizontais e dos esfor?os internos (esfor?o cortante e momento fletor) durante o processo construtivo da estrutura. As simula??es num?ricas inclu?ram avalia??es da influ?ncia do comprimento da ficha, do espa?amento horizontal entre os tirantes, da espessura da parede e do comprimento do trecho livre. O perfil de solo utilizado nas simula??es num?ricas ? representativo de uma determinada regi?o da Cidade de Natal RN, na qual s?o constru?das com frequ?ncia conten??es do tipo analisado no presente trabalho. Utilizou-se o modelo constitutivo de Mohr-Coulomb para simular o comportamento do solo e o modelo el?stico linear para simular o comportamento dos elementos estruturais. Os par?metros de resist?ncia do solo foram determinados por meio de ensaios de cisalhamento direto e os par?metros de deformabilidade foram estimados atrav?s de correla??es emp?ricas obtidas de resultados de ensaios SPT executados na regi?o em estudo. Os resultados obtidos mostraram que varia??es no comprimento da ficha praticamente n?o influenciam o comportamento da estrutura, no ?mbito dos par?metros avaliados, ao passo que o espa?amento horizontal entre os tirantes apresenta forte influ?ncia sobre essas grandezas. Verificou-se tamb?m que a espessura da parede apresenta consider?vel influ?ncia sobre os deslocamentos horizontais e sobre os esfor?os internos e pouca influ?ncia sobre as tens?es horizontais

[pt] Nesta tese relato aplicações das estruturas leves de bambu. Na primeira parte do trabalho trato da história passada e da história contemporânea do emprego no mundo das estruturas estabilizadas pela união entre bambus e cabos. Os objetivos dessas estruturas, alguns dos seus precursores e suas experiências são citadas. O uso popular de estruturas feitas com esses materiais é tornado manifesto com imagens e textos referentes. A seguir tratamos dos modos artesanais de suas feituras e da passagem de sua técnica para espaços de convivência sendo enfatizado o efeito cultural do trabalho amoroso e detalhado de transmitir a maneira de fazer os objetos. Na segunda parte do trabalho apresento o estado da Arte no Laboratório de Investigação em Living Design (LILD), do Departamento de Artes e Design (DAD) da PUC-Rio, no campo destas estruturas. São narradas atividades de passagem das técnicas em 3 (três) comunidades situadas no estado do Rio de Janeiro: a) na aldeia dos professores indígenas KUAA MBO E Guarani em Parati, no LILD e no CENAM (Centro de Acolhida Missionária); b) no Parque Estadual da Ilha Grande (PEIG), na Escola Municipal Brigadeiro Nóbrega; c) na Escola de Circo no espaço Crescer e Viver com o grupo Nós nos Nós - tragédias e comédias aéreas. Relato também a metodologia utilizada em sua dinâmica as suas relações e vínculos, com a graduação e pós-graduação em Design e com outros setores da Universidade. São narradas a passagem das técnicas, a elaboração e uso dos protótipos. Distingo as conexões utilizadas nestas estruturas feitas com bambus e cabos, chamadas do tipo vigas recíprocas, popularmente chamadas de giro, que vem sendo utilizadas nacionalmente e internacionalmente. / [en] In this thesis report applications of lightweight structures with bamboo. In the first part of the tract of past history and contemporary history of employment in the world of structures stabilized by the union of bamboo and cables. The objectives of these structures, some of its precursors and their experiences are cited. The popular use of structures made with these materials is made manifest in images and texts related. Below we deal with the ways of their craft and making the passage of his technique for living space and emphasized the cultural effect of loving work and detailed way forward to make the objects. In the second part of the present state of the art in the Research Lab in Living Design (Lild), Department of Art and Design (DAD) of PUC-Rio, in the field of these structures. Activities are recounted in passing techniques in 3 (three) communities located in the state of Rio de Janeiro: a) teachers in the village of indigenous Guarani KUAA MBO E in Parati, and Lild CENAM (Center Welcoming Mission), b)State Park of Ilha Grande (Peig), the Municipal School Brigadier Nóbrega c) at Circus School Living and Growing in space with the group We We - air tragedies and comedies. Account also the methodology used in its dynamics and its relations ties with undergraduate and graduate design and other sectors of the University. Are told the passage of the techniques, the development and use of prototypes. Distinguish the connections used in these structures made of bamboo and wire, called the reciprocal type beams, popularly called spin, which is being used nationally and internationally.

Uppsatsen undersöker hur Emballator Växjöplast prioriterar och resonerar kring aspekterna volymutnyttjande, plocktid, säkerhet, kapitalbindning och servicenivå vid optimering av deras färdigvarulager. Författarna kom fram till följande slutsats: Fallföretaget prioriterar säkerhet högst för att skydda individen Servicenivå prioriteras efter säkerhet då de arbetar kundfokuserat. Efter servicenivå prioriteras volymutnyttjande för att minska sin externlagring. Plocktid prioriteras efter volymutnyttjande där målsättningen är att undvika nyanställningar. Sist prioriteras kapitalbindning då denna inte är fokus för logistikfunktionen.   Vidare undersöker författarna hur en multi-criteria optimization av aspekterna vid optimering av färdigvarulagret kan gå till. Författarna kommer fram till följande slutsatser: The main criteria method är bäst lämpad optimeringsmetod. Volymutnyttjande ska minimeras givet att resterande aspekter uppfyller respektive bivillkor. De flesta förvaringsmetoder och artikelplaceringar uppfyller aspekternas bivillkor Bäst lämpad förvaringsmetod och artikelplacering grundas därför på vilken som möjliggör bäst volymutnyttjande. Slutligen utvärderas Emballator Växjöplasts nuvarande färdigvarulager sett till aspekterna utifrån analysen för frågeställning 2. Här presenteras även kortsiktiga och långsiktiga förbättringsförslag. Författarna kom fram till följande slutsats: Deras nuvarande förpackning, förvaringsmetod samt artikelplacering tillgodoser respektive bivillkor men kan förbättras sett till the main criteria, volymutnyttjande. Ett kortsiktigt förbättringsförslag genom att utföra en liknande artikelplacering på bättre sätt kan upp till 38-57 fler pallar rymmas på färdigvarulagret. Ett långsiktigt förbättringsförslag genom att kombinera traditionella pallställage och drive-through eller push-back-hyllor, kan totala antal pallplatser på färdigvarulagret öka med 18,4 %. / The essay examines how Emballator Växjöplast prioritize and reason among the aspects safety, service level, utilization rate, order picking time and capital tied up in inventory when optimizing their finished goods warehouse. The authors came to the following conclusion: Firstly, they prioritize safety the highest to protect the individuals within the warehouse. Service level is prioritized secondly because they operate with a customer focus. After service level utilization rate is prioritized to lower their need for external storage. Order picking time is prioritized after utilization rate with the goal to avoid the need for employing more operators within the warehouse. Lastly capital tied up in inventory is prioritized because the aspect is not in focus for the logistics department.   Moreover, the authors investigate how multi-criteria optimization as an optimization method can be used when optimizing a finished goods warehouse considering several contradictive aspects and the conclusion is: The main criteria method is best suited in optimization method. Utilization rate is the main criteria and the other aspects are constraints. The majority of storage systems and storage assignment policy are within the constraints. The best storage systems and storage assignment policy is therefore mainly determined by the main criteria.   Lastly a discussion regarding the finished goods warehouse is held and both short term and long term improvements regarding the aspects are presented. The conclusions made by the authors are as follows: Their current packaging, storage systems and storage assignment policy is sufficient in terms of the different constraints but the main criteria can be improved. Short term improvements are to use a similar storage assignment policy in a better way and enable room for 38-57 more pallets in the finished goods warehouse. Long term improvements are to improve both storage assignment policy and the storage system. By combining traditional racks with some other storage system such as drive-through or push-back-shelves the number of pallets that can fit within the warehouse can increase by 18,4%.