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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.
171

Vantagem competitiva que cresce em árvore: um estudo sobre integração vertical na cadeia de papel e celulose do Brasil

Schmidt, Rodrigo de Holanda 30 November 2017 (has links)
Submitted by RODRIGO DE HOLANDA SCHMIDT (rodrigohs1979@gmail.com) on 2018-01-17T18:29:25Z No. of bitstreams: 1 PROJETO Posdefesa Versão FINAL.pdf: 1906537 bytes, checksum: 3b5e67507ea1b0d7bda550480252ae26 (MD5) / Approved for entry into archive by Janete de Oliveira Feitosa (janete.feitosa@fgv.br) on 2018-01-18T18:30:52Z (GMT) No. of bitstreams: 1 PROJETO Posdefesa Versão FINAL.pdf: 1906537 bytes, checksum: 3b5e67507ea1b0d7bda550480252ae26 (MD5) / Made available in DSpace on 2018-01-30T12:08:34Z (GMT). No. of bitstreams: 1 PROJETO Posdefesa Versão FINAL.pdf: 1906537 bytes, checksum: 3b5e67507ea1b0d7bda550480252ae26 (MD5) Previous issue date: 2017-11-30 / Purpose – The aim of this study was to comprehend the main determinant factors for vertical integration in the pulp and paper sector in Brazil, from a perspective of pulp manufacturers. Design/methodology – The research adopted a qualitative approach, through a multiple case study with three of the main companies in the pulp and paper sector in Brazil. The data collection was done through semi-structured interviews of executives of the selected companies. Findings – The main competitive advantage arises from the vertical integration backward, of the pulp mill towards the forestry. The main factors for this are the exercise of the market power of oligopoly by the pulp companies, assurance of supply of their main input, the wood, asset specificity of site, shortening the distance between the forest and the pulp mill, and mitigation of uncertainty. There is tapered integration of pulp mill and forestry, mainly due the use of advantages of site specificity of forest producers near the mill, the need to mitigate social risks and to develop a mature market for the commercialization of wood in the country. Research limitations – The main limitation of this work is the fact that the pulp sector is a concentrated oligopoly, with few companies, which restricts the diversity and number of respondents. Practical implications – The results can be applied to organizations in the pulp and paper sector, as well as to other capital-intensive industries with high dependence on a particular raw material. Originality– To our knowledge, this is the first study about vertical integration in the pulp and paper sector in Brazil. / Objetivo – Este estudo pretende compreender os principais determinantes para a integração vertical no setor de papel e celulose no Brasil, a partir de uma perspectiva das fabricantes de celulose. Metodologia – A pesquisa seguiu uma abordagem qualitativa, por meio de estudo de casos múltiplos com três das principais empresas do setor de papel e celulose do Brasil. A coleta de dados foi feita por meio de entrevistas semiestruturadas de executivos das empresas selecionadas. Resultados – A principal vantagem competitiva verificada se deu na integração vertical realizada à montante pela fábrica de celulose, em direção à produção florestal. Os principais fatores para isso foram o exercício do poder de mercado de oligopólio pelas empresas de celulose, a garantia de fornecimento do seu insumo principal, a madeira, a especificidade de local dos ativos, dada pela proximidade necessária entre a floresta e a unidade de celulose, e a mitigação da incerteza. A integração vertical entre fábrica de celulose e produção florestal é realizada de forma parcial, principalmente devido ao aproveitamento de vantagens de localização de produtores florestais próximos à fabrica, à necessidade de mitigar riscos sociais e de desenvolver um mercado maduro de comercialização de madeira no país. Limitações – A principal limitação deste trabalho é o fato do setor de celulose ser um oligopólio concentrado, com poucas empresas, o que restringe a diversidade e o número de entrevistados. Aplicabilidade do trabalho – Os resultados obtidos podem ser aplicados às organizações do setor de papel e celulose, bem como a outras indústrias de capital intensivo e com alta dependência de uma matéria-prima em especial. Originalidade – Pelo que conhecemos, é o primeiro trabalho sobre integração vertical no setor de papel e celulose no Brasil.
172

Mekanisk mjukgöring av pappersgarn : En studie om smärgling av pappersgarn samt behandlingens påverkan på de taktila egenskaperna / Mechanical softening of paper yarn

Vasell, Anna, Ronkainen, Julia January 2017 (has links)
En förväntad ökning av jordens befolkning ställer den redan ökande fiberkonsumtionen på sin spets. Bomull är en av de mest frekvent använda textilfibrerna men dess vatten- och kemikalieanvändning i framställningsprocessen har lett till förödande konsekvenser för människa och miljö. Flera alternativa, hållbara fibrer behöver därmed introduceras på marknaden. Garn av papper från råvaran abacá har länge använts till textila ändamål till följd av dess goda mekaniska egenskaper. På senare år har intresset för fibern ökat främst på grund av dess miljömässiga fördelar i jämförelse med bomull. Garn av papper är dock styvt och känns strävt mot huden. För att vidga pappersgarnets användningsområden måste därför dess taktila egenskaper förbättras genom någon typ av behandling. Textilproduktion är kemikaliekrävande och flertalet av kemikalierna som används är miljö- och hälsofarliga. Det är därför av intresse att hitta en mekanisk metod för mjukgöring snarare än en kemisk. En sådan mjukgöring har därav utvecklats och undersökts inom projektets ramar. Mjukgöringen är en smärglingsbehandling i garnform där garnet leds genom en bladspännare utrustad med två sandpapper som smärgeldukar. Behandlingen ämnar öka antalet utstickande fiberändar och på så vis efterlikna känslan av ett stapelfibergarn. Genom att garnet behandlas redan i garnstadiet kan det sedan användas till valfri textil konstruktionsteknik. För att undersöka effekten av smärglingsbehandlingen har studien delats in i två delar. Den ena delen undersöker två klassiska denimvävar av 100 % papper där väftgarnet i den ena väven har smärglats en gång medan väftgarnet i den andra är obehandlat. Kawabata Evaluation System (KES) har använts för att objektivt analysera vävarnas taktila egenskaper, alltså hur de känns vid beröring. För att undersöka hur vävens ytstruktur förändrats till följd av behandlingen har provkropparna fotograferats i svepelektronmikroskop (SEM) och ljusmikroskop. Studiens andra del undersöker effekten av upprepade smärglingsbehandlingar på garn. Pappersgarner som behandlats mellan noll och fem gånger undersöks dels gällande dess mekaniska egenskaper men även visuellt i SEM och med hjälp av ljusmikroskop. Behandlingen förväntas minska garnets styrka. För att kontrollera om de behandlade garnerna är tillräckligt starka för att användas i en industriell vävprocess trots den mekaniska degraderingen jämfördes deras styrka med ett referensgarn av bomull. Majoriteten av resultaten från KES-testerna visar på att det inte är någon skillnad mellan en obehandlad väv och en väv vars väftgarn är smärglat en gång. Den behandlade väven är dock lättare att komprimera och har en större initial tjocklek än den obehandlade väven. Detta tyder på att smärglingen kan ha ändrat garnernas diameter vilket resulterat i högre invävning och därmed ökad vikt och tjocklek. Den visuella undersökningen av garnerna i ljusmikroskop pekar mot ett ökat antal utstickande fiberändar i takt med ökat antal behandlingar. Dock är skillnaden mellan det osmärglade garnet och det garn som enbart smärglats en gång liten. Dragprovning av garn visar att det pappersgarn som smärglats fem gånger har signifikant lägre brottkraft än de övriga pappersgarnerna men är starkare än referensgarnet i bomull. Detta styrker förväntningen om att smärgling försämrar styrkan på garnet men visar också att de behandlade garnerna, trots den minskade styrkan, bör vara tillräckligt starka för att användas som väftgarn i maskinell vävning. Fiberändarnas effekt i en denimväv behöver undersökas vidare för att en slutsats kring hur de påverkar den taktila komforten ska kunna dras. Metoden för garnsmärgling är i sin initiala fas och flera parametrar behöver undersökas närmare innan metoden skulle kunna implementeras på industriell skala som en metod för mjukgöring av pappersgarn med syfte att främja den framtida fibermångfalden. / An expected population increase and rising consumption of textile fibres creates a demand for both new materials and processes. Cotton is one of the most frequently used fibres but its use is resource intensive both in terms of water and chemical agents. To meet these demands a range of alternative, sustainable fibres need to be developed and introduced into the market. Due to its good mechanical properties paper yarns produced from the abacá plant have long been used in textile applications. In recent years it has also garnered increased interest as a result of its environmental benefits in comparison to cotton. However, paper yarns tend to be stiff and feel coarse in contact with skin. In order for paper yarns to have larger fields of use its tactile qualities must therefore be improved. The production of textiles is generally reliant on the use of chemicals that in varying degree pose threats both to human health and the environment as a whole. It would therefore be beneficial to develop a method for the softening of paper yarns that is based on a mechanical approach, rather than a chemical one. In this project a mechanical method of softening paper yarns has been developed and tested. The softening process is an altered approach to conventional emery grinding and is performed on yarn rather than fabric. The yarn is guided through a leaf tensioner fitted with two sand papers with the purpose to increase the number of protruding fibre ends, thereby reproducing the feel of staple fibre yarns. In order to investigate the effects of the emery grinding two classical denim weaves were produced from 100 % paper yarn. The weft yarn in one of the weaves was emery ground once while the other was left untreated. Kawabata Evaluation System (KES) was used to objectively analyze the tactile qualities of the differently treated weaves. In addition to KES-tests Scanning Electron Microscopy and light microscopy was utilized for a visual analysis. Since it would also be of interest to study the effects of repeated treatments, yarn treated up to five times was inspected both visually and mechanically. The emery grinding process is expected to decrease the strength of the yarn. To check whether the emery ground yarns were strong enough to be used in an industrial weaving process, its strength was compared to a cotton yarn previously used as a weft yarn in a denim weave. Results from KES show no significant changes concerning the majority of parameters tested on the weaves. The treated weave is however easier to compress and presents an increase in initial thickness when compared to the untreated one. This indicates that the emery grinding may have altered the yarns diameter resulting in a higher crimp in the weave causing an increase in the weight and thickness of the fabric. The visual inspection of the yarns using a digital microscope point to an increase in protruding fibre ends as the number of treatments increase. The difference between untreated paper yarn and yarn that had been emery ground once was however small. The tensile test shows that yarn that had been treated five times had a significantly lower tensile strength compared to the other paper yarns but was still stronger than the cotton yarn. This indicates that emery grinding does indeed decrease the tensile strength of the paper yarn, but that it still should be strong enough to be used in industrial weaving. Paper yarn treated more than once would have to be studied further in order to come to a conclusion about their impact on the tactile comfort of the weave. The method of emery grinding is in its initial phase and a number of parameters can be assumed to have an effect on the results of the process. In the interest of creating more diversity in textile fibres the effects of these parameters would all have to be explored before this method can be implemented on an industrial scale for the softening of paper yarns.
173

Three Essays on the Measurement of Productivity

Hussain, Jakir January 2017 (has links)
This doctoral thesis consists of three essays. In the first essay I investigate the presence of productivity convergence in eight regional pulp and paper industries of U.S. and Canada over the period of 1971-2005. Expectation of productivity convergence in the pulp and paper industries of Canadian provinces and of the states of its southern neighbour is high since they are trading partners with fairly high level of exchanges in both pulp and paper products. Moreover, they share a common production technology that changed very little over the last century. I supplement the North-American regional data with national data for two Nordic countries, Finland and Sweden, which provides a scope to compare the productivity performances of four leading players in global pulp and paper industry. I find evidence in favour of the catch-up hypothesis among the regional pulp and paper industries of U.S. and Canada in my sample. The growth performance is at the advantage of Canadian provinces relative to their U.S. counterparts. However, it is not good enough to surpass the growth rates of this industry in the two Nordic countries. It is well-known that econometric productivity estimation using flexible functional forms often encounter violations of curvature conditions. However, the productivity literature does not provide any guidance on the selection of appropriate functional forms once they satisfy the theoretical regularity conditions. The second chapter of my thesis provides an empirical evidence that imposing local curvature conditions on the flexible functional forms affect total factor productivity (TFP) estimates in addition to the elasticity estimates. Moreover, I use this as a criterion for evaluating the performances of three widely used locally flexible cost functional forms - the translog (TL), the Generalized Leontief (GL), and the Normalized Quadratic (NQ) - in providing TFP estimates. Results suggest that the NQ model performs better than the other two functional forms in providing TFP estimates. The third essay capitalizes on newly available high frequency energy consumption data from commercial buildings in the District of Columbia (DC) to provide novel insights on the realized energy use impacts of energy efficiency standards in commercial buildings. Combining these data with hourly weather data and information on tenancy contract structure I evaluate the impacts of energy standards, contractual structure of utility bill payments, and energy star labeling on account level electricity consumption. Using this unique panel dataset, the analysis takes advantage of detailed building-level characteristics and the heterogeneity in the building age distribution, resulting in buildings constructed before and after mandatory energy standards came into effect. Estimation results suggest that in commercial buildings constructed under a code, electricity consumption is lower by about 0.48 kWh per cooling degree hour. When tenants pay for their own utilities, consumption is lower by 0.82 kWh per cooling degree hour. The Energy Star effect is a 0.31 kWh reduction per cooling degree hour. Finally, peak savings for all three variables of interest occur at 2pm in the summer months, whereas peak summer marginal prices at DC's local electric utility occur at 5pm.
174

Artificial Intelligence in the Pulp and Paper Industry : Current State and Future Trends / Artificiell Intelligens i Massa- och Pappersindustrin : Nuläge och Framtida Trender

Nystad, Marcus, Lindblom, Lukas January 2020 (has links)
The advancements in Artificial Intelligence (AI) have received large attention in recent years and increased awareness has led to massive societal benefits and new opportunities for industries able to capitalize on these emerging technologies. The pulp and paper industry is going through one of the most considerable transformations into Industry 4.0. Integrating AI technology in the manufacturing process of the pulp and paper industry has shown great potential, but there are uncertainties which direction companies are heading. This study is an investigation of the pulp and paper industry in collaboration with IBM that aims to fill a gap between academia and the progress companies are making. More specifically, this thesis is a multiple case study of the current state and barriers of AI technology in the Swedish pulp and paper industry, the future trends and expectations of AI and the way organizations are managing AI initiatives Semi-structured interviews were conducted with 11 participants from three perspectives and the data was thematically coded. Our analysis shows that the use of AI varies, and companies are primarily experimenting with a still immature technology. Several trends and areas with future potential were identified and it was shown that digital innovation management is highly regarded. We conclude that there are several barriers hindering further use of AI. However, continued progress with AI will provide large benefit long term in areas such as predictive maintenance and process optimization. Several measures taken to support initiatives with AI were identified and discussed. We encourage managers to take appropriate actions in the continued work toward AI integration and encourage further research in the area of potential reworks in R&D. / Framgångarna inom Artificiell Intelligens (AI) har fått stor uppmärksamhet de senaste åren och ökad medvetenhet har lett till stora fördelar för samhället liksom nya möjligheter för industrier som tar vara på dessa nya teknologier. Pappers- och massa industrin genomgår en av de mest omfattande transformationerna mot Industri 4.0. Integreringen av AI-teknologi i industrins tillverkningsprocesser has visat stor potential, men också osäkerhet kring vilken riktning företag är på väg mot. Denna studie är en undersökning av den svenska pappers- och massaindustrin, i samarbete med IBM, som syftar till att minska gapet mellan akademin och framstegen företag inom industrin tar. Mer specifikt är denna uppsats en kombinerad fallstudie av det nuvarande läget, barriärerna till AI-teknik i den svenska pappers- och massa industrin, de framtida trenderna och förväntningarna på AI och metoderna företag använder för att stötta AI-initiativ. Semi-strukturerade intervjuer genomfördes med 11 deltagare från tre olika perspektiv och datan var tematiskt kodad. Vår analys visar att användning av AI varierar och företag experimenterar huvudsakligen med omogen teknik. Flera trender och områden med potential för framtiden identifierades och det visades att digital innovationshantering är högt ansedd. Vi sammanfattar med att det finns flera barriärer som hindrar fortsatt användning av AI. Fortsatt arbete med AI-tekniken kommer leda till stora fördelar på lång sikt inom områden som prediktivt underhåll och fortsatt processoptimering. Flera åtgärder för att stötta AI-initiativ var identifierade och diskuterades. Vi uppmuntrar industrin att genomföra lämpliga åtgärder i det fortsatta arbetet mot AI-integration och uppmuntrar fortsatt forskning inom potentiella omstruktureringar inom FoU.

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