• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 32
  • 10
  • 4
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 74
  • 74
  • 22
  • 15
  • 9
  • 8
  • 8
  • 8
  • 7
  • 7
  • 7
  • 7
  • 7
  • 6
  • 6
  • 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.
41

An analysis of factors influencing quality perceptions and purchase of office furniture

Hansen, Bruce G. 14 October 2005 (has links)
This dissertation presents an in depth investigation of the office furniture industry and of the factors that influence selection and purchase of office furniture. It also utilizes data obtained in a national survey of nearly 270 office furniture buyers to investigate several general conceptual marketing issues. The industry-specific investigation includes a look at the history of the office and at events during the past 2-1/2 decades that have impacted the market for office furniture. It also includes a comparative look at the relative performance of wood (SIC 2521) and metal (SIC 2522) industry sectors. The performance of the office furniture industry is also compared with the wood household furniture industry (SIC 2511). This report includes a detailed look at the industry's changing product mix and use of wood-based materials. While the total use of wood-based material inputs by the industry was at record levels for all material categories in 1987, use on a per unit of output basis declined in several material categories. Material preferences, as expressed by survey respondents, indicated that solid wood is still rated highly and is the material of choice for interior and exterior applications in conventional office furniture manufacture. Twenty-six attributes of office furniture and of dealer/manufacturer services were rated on dual 7- and 5-point Likert scales for importance and difference, respectively. The most important attribute was the ability of the dealer manufacturer to provide products free of defects. However, when differences in the performance of suppliers or products were taken into account, the top determinant attribute was the ability to deliver on schedule. Comparisons of quality and selection and purchase ratings suggested that respondents tended to rate attributes on the bases of their use in selection and purchase higher overall than they rated their use in assessing quality. However, the relative ranking of attributes within the two sets of ratings were highly correlated. Respondent ratings of the 26 attributes were utilized in a multivariate study of quality dimensions employing confirmatory and exploratory factor analyses. Results of these analyses supported operationalization of most of Garvin's eight dimensions of quality. / Ph. D.
42

Improving domestic markets for the wood products of reforestation programs: a case study of eucalyptus in northwestern Senegal

Merry, Frank 04 August 2009 (has links)
There is a drastic need for reforestation in the Sahel region of Africa. International donors and local governments invest large sums of money for the purpose of planting trees. Unfortunately, the majority of reforestation efforts last only as long as the projects. Presently there is a push in the donor community to have more sustainable projects, increasing local participation and creating a situation in which reforestation efforts will continue beyond the scope of any one project. This thesis examines the potential opportunity for the use of eucalyptus in the domestic sawn wood markets of Senegal. It is hoped that with increased economic incentives the local population will become more inclined to plant trees. It is therefore important to identify the market opportunities for the products of reforestation. In this research it has been noted that more emphasis should be placed on determining the barriers to market entry for the goods to be produced from the reforestation and providing assistance to lower those barriers. In Senegal it is generally accepted that planting for fuel wood and housepoles does not provide enough of an economic incentive for increased local involvement in reforestation. This thesis finds that the domestic sawn wood market for eucalyptus in Senegal holds potential but will not provide tangible benefits until there are further improvements in the market infrastructure and communication to the farmer. To increase the participation in this market the people of Senegal need to see for themselves that reforestation can be financially beneficial. Reforestation projects rust have a longer-term vision and provide assistance throughout the productive cycle of the tree. / Master of Science
43

Product-market opportunities for FPL spaceboard II molded structural products

Trinka, Mark W. 31 October 2009 (has links)
Two analysis techniques were demonstrated for use in new product development by the wood products industry. A new molded wood structural product developed by the U.S. Forest Service Forest Products Laboratory known as FPL Spaceboard II was used to illustrate the techniques. Determinant attribute analysis was first employed to identify the product attributes most important to purchase decisions regarding substrate materials for the office furniture industry - the most likely target for introduction of Spaceboard II. A matrix-type decision model was then developed and illustrated which assists in selecting the most attractive product-market opportunity for a new product still in the development stages based on market attractiveness and relative competitive advantage of the product. Surveys were directed to manufacturers of office furniture and to producers of industrial particleboard and medium-density fiberboard which currently are the most common materials utilized as substrates in the office furniture industry. The furniture survey collected information regarding the perceived importance and variability of an array of physical product characteristics in the selection of a substrate material for office furniture. The survey of industrial particleboard and medium-density fiberboard producers acquired information regarding the importance of factors affecting decisions to enter and compete in a given market and ratings of the office furniture substrate market on those factors. The results of the determinant attribute analysis indicated that fastener withdrawal strength, surface smoothness, flatness, stiffness (MOE), and edgebanding capability were the product attributes which would most affect the decision to purchase substrate material for office furniture, and consequently are the attributes to focus on in developing a new product for that market. Use of the decision model was illustrated with Spaceboard II and resulted in a hypothetical matrix with the product positioned based on the attractiveness of the office furniture substrate market and Spaceboard II’s relative competitive advantage over existing materials in that market versus its competitive position in other market scenarios. / Master of Science
44

Street Trees as a Source of Timber in Washington, DC

Grieve, Alexander Joseph 24 January 2017 (has links)
Recycling felled urban trees that are hazardous or unhealthy is increasingly viewed as a viable practice to control disposal costs, promote environmental practices, and support local commerce. Wide spread waste wood utilization is encumbered by numerous presumptions about wood quantity, quality, accessibility, and presence of foreign objects; yet there is almost no scientific literature about these presumptions. Without this knowledge, informed decisions cannot be made about the viability of waste wood utilization. In this study, we assessed the quality and quantity of timber in street trees scheduled for routine removal by the District of Columbia (the District) using a modified timber grading protocol adapted from the United States Forest Service. We developed a second protocol to assess the feasibility of timber salvage by identifying physical barriers commonly encountered in urban areas (e.g., high volume traffic, utilities around the tree, and infrastructure). The randomized sampling scheme was stratified by land-use zones and focused on the six most abundant tree species: Acer platanoides, Acer rubrum, Acer saccharum, Quercus palustris, Quercus phellos, Quercus rubra. Our findings suggest the majority of condemned street trees are of too poor quality to contain timber (58% cull rate); however, trees that contain merchantable logs are likely to be easily removed. A notable discovery that could prove problematic for wood salvage was that the majority of trees (88%) contained superficial metal items embedded in the trunk surface. Furthermore, presence or absence of a merchantable-sized log (p=0.0445) depended on the tree's species, as did the average volume observed (p<0.0001). Additionally, land-use zones had an effect on the removal feasibility scores (p=0.0257) but had no effect on log presence or log volume. Throughout the District, we estimated that 36,500 board feet of merchantable logs are generated from routine removals of our top six species annually. These findings provide empirical data pertaining to urban timber salvage, which might aid decisions on the investment worthiness of utilizing urban street trees. / Master of Science / Recycling felled urban trees that are hazardous or unhealthy is increasingly viewed as a viable practice to control disposal costs, promote environmental practices, and support local commerce. Wide spread waste wood utilization is encumbered by numerous presumptions about wood quantity, quality, accessibility, and presence of foreign objects; yet there is almost no scientific literature about these presumptions. Without this knowledge, informed decisions cannot be made about the viability of waste wood utilization. In this study, we assessed the quality and quantity of timber in street trees scheduled for routine removal by the District of Columbia (the District) using a modified timber grading protocol adapted from the United States Forest Service. We developed a second protocol to assess the feasibility of timber salvage by identifying physical barriers commonly encountered in urban areas (e.g., high volume traffic, utilities around the tree, and infrastructure). The randomized sampling scheme was stratified by land-use zones and focused on the six most abundant tree species: <i>Acer platanoides, Acer rubrum, Acer saccharum, Quercus palustris, Quercus phellos, Quercus rubra</i>. Our findings suggest the majority of condemned street trees are of too poor quality to contain timber (58% cull rate); however, trees that contain merchantable logs are likely to be easily removed. A notable discovery that could prove problematic for wood salvage was that the majority of trees (88%) contained superficial metal items embedded in the trunk surface. Furthermore, presence or absence of a merchantable-sized log (p=0.0445) depended on the tree’s species, as did the average volume observed (p<0.0001). Additionally, land-use zones had an effect on the removal feasibility scores (p=0.0257) but had no effect on log presence or log volume. Throughout the District, we estimated that 36,500 board feet of merchantable logs are generated from routine removals of our top six species annually. These findings provide empirical data pertaining to urban timber salvage, which might aid decisions on the investment worthiness of utilizing urban street trees.
45

The impact of silvicultural strategies and climate change on carbon sequestration and other forest ecosystem functions

Fürstenau, Cornelia January 2008 (has links)
Forests are a key resource serving a multitude of functions such as providing income to forest owners, supplying industries with timber, protecting water resources, and maintaining biodiversity. Recently much attention has been given to the role of forests in the global carbon cycle and their management for increased carbon sequestration as a possible mitigation option against climate change. Furthermore, the use of harvested wood can contribute to the reduction of atmospheric carbon through (i) carbon sequestration in wood products, (ii) the substitution of non-wood products with wood products, and (iii) through the use of wood as a biofuel to replace fossil fuels. Forest resource managers are challenged by the task to balance these multiple while simultaneously meeting economic requirements and taking into consideration the demands of stakeholder groups. Additionally, risks and uncertainties with regard to uncontrollable external variables such as climate have to be considered in the decision making process. In this study a scientific stakeholder dialogue with forest-related stakeholder groups in the Federal State of Brandenburg was accomplished. The main results of this dialogue were the definition of major forest functions (carbon sequestration, groundwater recharge, biodiversity, and timber production) and priority setting among them by the stakeholders using the pair-wise comparison technique. The impact of different forest management strategies and climate change scenarios on the main functions of forest ecosystems were evaluated at the Kleinsee management unit in south-east Brandenburg. Forest management strategies were simulated over 100 years using the forest growth model 4C and a wood product model (WPM). A current climate scenario and two climate change scenarios based on global circulation models (GCMs) HadCM2 and ECHAM4 were applied. The climate change scenario positively influenced stand productivity, carbon sequestration, and income. The impact on the other forest functions was small. Furthermore, the overall utility of forest management strategies were compared under the priority settings of stakeholders by a multi-criteria analysis (MCA) method. Significant differences in priority setting and the choice of an adequate management strategy were found for the environmentalists on one side and the more economy-oriented forest managers of public and private owned forests on the other side. From an ecological perspective, a conservation strategy would be preferable under all climate scenarios, but the business as usual management would also fit the expectations under the current climate. In contrast, a forest manager in public-owned forests or a private forest owner would prefer a management strategy with an intermediate thinning intensity and a high share of pine stands to enhance income from timber production while maintaining the other forest functions. The analysis served as an example for the combined application of simulation tools and a MCA method for the evaluation of management strategies under multi-purpose and multi-user settings with changing climatic conditions. Another focus was set on quantifying the overall effect of forest management on carbon sequestration in the forest sector and the wood industry sector plus substitution effects. To achieve this objective, the carbon emission reduction potential of material and energy substitution (Smat and Sen) was estimated based on a literature review. On average, for each tonne of dry wood used in a wood product substituting a non-wood product, 0.71 fewer tonnes of fossil carbon are emitted into to the atmosphere. Based on Smat and Sen, the calculation of the carbon emission reduction through substitution was implemented in the WPM. Carbon sequestration and substitution effects of management strategies were simulated at three local scales using the WPM and the forest growth models 4C (management unit level) or EFISCEN (federal state of Brandenburg and Germany). An investigation was conducted on the influence of uncertainties in the initialisation of the WPM, Smat, and basic conditions of the wood product sector on carbon sequestration. Results showed that carbon sequestration in the wood industry sector plus substitution effects exceeded sequestration in the forest sector. In contrast to the carbon pools in the forest sector, which acted as sink or source, the substitution effects continually reduced carbon emission as long as forests are managed and timber is harvested. The main climate protection function was investigated for energy substitution which accounted for about half of the total carbon sequestration, followed by carbon storage in landfills. In Germany, the absolute annual carbon sequestration in the forest and wood industry sector plus substitution effects was 19.9 Mt C. Over 50 years the wood industry sector contributed 70% of the total carbon sequestration plus substitution effects. / Wälder beeinflussen in vielfältiger Weise unser Leben. Für den Waldbesitzer sind sie Einkommensquelle, die Holzindustrie versorgen sie mit dem Rohstoff, aus dem unzählige Dinge für den täglichen Bedarfs hergestellt werden, wie zum Beispiel Baumaterialien, Möbel, Gartengeräte, Spielzeug und Papier. Außerdem versorgen Wälder uns mit sauberem Grundwasser, sind Lebensraum für Pflanzen und Tiere und tragen somit zum Erhalt der Artenvielfalt bei. Nicht zuletzt beeinflussen Wälder das Klimasystem, da sie der Atmosphäre das Treibhausgas CO2 entziehen und Kohlenstoff in Biomasse und Boden speichern. Förster stehen nun vor der anspruchsvollen Aufgabe, eine Balance zwischen den vielfältigen und oft auch gegensätzlichen Waldfunktionen zu finden und die Ansprüche von Interessengruppen wahrzunehmen. Zusätzlich müssen im waldbaulichen Entscheidungsprozess Risiken und Unsicherheiten durch unberechenbare externe Faktoren, wie das Klima, beachtet werden. Ziel der Arbeit war es, den Einfluss von Klima und Waldbaustrategien auf Waldfunktionen zu untersuchen. Als Testgebiet fungierte das Revier Kleinsee im Südosten Brandenburgs, in dem Kiefern- und Eichenbestände vorherrschen. In einem wissenschaftlichen Dialog mit Angestellten der Forstbehörde, Privatwaldbesitzern, Vertretern von Naturschutzverbänden sowie Wissenschaftlern definierten die Teilnehmer die wichtigsten Waldfunktionen: Kohlenstoffspeicherung, Grundwasserneubildung, Biodiversität und Holzproduktion. Die Simulationen wurden mit Hilfe des Waldwachstumsmodells 4C und einem neu implementierten Holzproduktmodell (WPM) über einen Zeitraum von 100 Jahren durchgeführt. Dabei wurden den heutigen Klimabedingungen zwei Klimaänderungsszenarien gegenübergestellt, die auf den globalen Zirkulationsmodellen HadCM2 und ECHAM4 basieren. Es stellte sich heraus, dass unter den angenommenen Klimaänderungen das Wachstum der Bestände steigt und sich damit die Kohlenstoffspeicherung und der Ertrag aus Holzernten erhöht, wohingegen Biodiversität und Grundwasserneubildung nur sehr gering beeinflusst werden. Der Nutzen der Waldbewirtschaftungsstrategien für drei Interessensgruppen (Forstbehörde, private Waldbesitzer, Naturschutzvereine) wurde mit einer multikriteriellen Analysemethode bewertet. Dabei unterschieden sich die Rangfolge und Gewichtung der einzelnen Waldfunktionen sowie die daraus resultierende Wahl der Waldbaustrategien zwischen den Naturschützern einerseits sowie den stärker ökonomisch orientierten Landeswaldförstern und privaten Waldbesitzern anderseits. Naturschutzvereine bevorzugen das Einstellen der Waldbewirtschaftung, aber auch die aktuelle Waldbaustrategie, mit mäßiger Durchforstungsintensität und einem hohen Anteil an Eichenbeständen entspricht ihren Zielsetzungen. Dagegen lag die Präferenz der Landeswaldförster sowie privaten Waldbesitzer auf einer Walbaustrategie mit einem hohen Anteil an Kiefernbeständen, um den Ertrag unter Beachtung der anderen Waldfunktionen zu steigern. Als Fazit geht aus dieser Teilstudie hervor, dass die Bewertung von Waldbaustrategien hinsichtlich ihrer Eignung für eine multifunktionale Waldbewirtschaftung unter Beachtung von Ansprüchen verschiedener Interessengruppen und ungewissen klimatischen Bedingungen unter Verwendung von 4C und einer multikriteriellen Analysemethode sehr gut möglich ist. Besonderes Augenmerk galt dem Einfluss von Waldbaustrategien auf den Kohlenstoffkreislauf, wobei nicht nur die Kohlenstoffspeicherung im Wald, sondern auch in Holzprodukten, sowie die Verringerung von CO2-Emissionen durch energetische und stoffliche Nutzung von Holz betrachtet wurden. Die potentielle Reduktion von CO2-Emissionen durch das Ersetzen von Erzeugnissen und Energie aus nicht nachwachsenden Rohstoffen durch Holz (Smat und Sen) wurde basierend auf Daten verschiedener Studien geschätzt. Eine Sensitivitätsanalyse untersuchte Unsicherheiten bei der Initialisierung des WPMs und der Berechung von Smat. Verschiedene Szenarien führten zu einem besseren Verständnis dafür, wie sich Änderungen im Energiesektor und Holzproduktsektor auf das Potential, Kohlenstoff zu speichern bzw. CO2-Emissionen zu verringen auswirken. Die Ergebnisse zeigen, dass die Reduzierung von CO2-Emissionen im Holzproduktsektor durch die Nutzung von Holz als Werkstoff und Brennstoff höher ist als durch die Akkumulation von Kohlenstoff im Wald. Im Gegensatz zu den Kohlenstoffspeichern im Wald, die sowohl Quellen als auch Senken sein können, werden durch die Nutzung von Holz CO2-Emissionen verringert, solange im Zuge der Waldbewirtschaftung Holz für die Weiterverarbeitung zur Verfügung gestellt wird. Simulationen auf Bundesebene ergaben, dass in Deutschland die Forst- und Holzwirtschaft jährlich dazu beitragen die CO2-Emissionen um 19,9 Mt Kohlenstoff zu verringern, wobei 70% auf die Holzindustrie und den Substitutionseffekt entfallen.
46

The Use Of Design Consultancy For Companies Producing Furniture On Contract Basis: The Case Of A Medium Sized Company In Turkey

Bayer, Ulku 01 April 2006 (has links) (PDF)
Contract furniture which is manufactured depending on the client&amp / #8217 / s design or specification requirements on a contract basis is executed in small and medium sized furniture companies in Turkey. This one-of-a-kind production organization provides component manufacturing opportunity to furniture SMEs via subcontracting. In this study, the use of design consultancy is investigated to understand how it should be used in the current organization, in order to implement this production system efficiently. This study also examines contract furniture production to have foresight for the development of furniture SMEs in Turkey. In a literature review, the generic context of contracting activities in relation to design activity is investigated. Methods of design consultancy use in product development processes are searched. Design consultancy in construction industry is examined Data about design and production capabilities of Turkish furniture SMEs is collected. Production planning processes of a contract furniture company was investigated and discussed in a case study. These two groups of data were compared in order to drive conclusions.
47

Chapa de media densidade (MDF) fabricada com poliuretana mono-componente derivada de oleo de mamona - caracterização por metodo destrutivo e por ultra-som / Medium density fiberboard manufactured with polyurethane derived from castor oil - characterization of destructive and nondestructive testing

Silva, Sergio Augusto Mello da 11 May 2003 (has links)
Orientador: Raquel Gonçalves / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-06T00:21:33Z (GMT). No. of bitstreams: 1 Silva_SergioAugustoMelloda_D.pdf: 3060293 bytes, checksum: 3514c54e017be522e62c07231642a540 (MD5) Previous issue date: 2003 / Resumo: As tecnologias para produção das chapas denominadas ¿Medium Density Fiberboard¿ (MDF), confeccionadas com fibras de madeiras de reflorestamento de baixo custo e resinas fenólicas provenientes de uréia, representam para vários setores industriais uma possibilidade de agregar valores às espécies com pouco interesse comercial, possibilitando para os seguimentos industriais investimento promissores. Um aspecto importante a ser considerado sobre a utilização de resinas fenólicas na confecção de chapas MDF é que produzem emissões tóxicas poluidoras da natureza e nocivas ao ser humano. Dentro deste contexto, de acordo com o ¿Protocolo de Quioto¿ de 1997, os países industrializados precisam diminuir suas emissões combinadas de gases de efeito estufa em pelo menos 5 % até 2012. Considerando-se as exigências do ¿Protocolo de Quioto¿, este trabalho objetivou avaliar o desempenho de chapas MDF confeccionadas com poliuretana (PU) derivada do óleo de mamona, pois este produto apresenta baixos teores de toxidez sendo classificado como não poluente e não tóxico ao ser humano. A caracterização das chapas foi realizada considerando-se a utilização do equipamento de ultra-som da Marca Steinkamp modelo BP7 com transdutoes de 45 kHz e a realização de ensaios físicos e mecânicos propostos pela EuroMDFBoard - EMB. A avaliação desenvolveu-se em três fases distintas: 1. Na fase I foram realizados estudos exploratórios com o objetivo de verificar as características do PU sendo utilizado como adesivo para confecção de chapas de Pinus caribaea. Nesta fase foram confeccionadas chapas com 5 e 10 % de PU3070, que de acordo com a caracterização física e mecânica observou-se que as chapas apresentaram resistências compatíveis com as exigências da EMB, entretanto, a forte exalação de solvente inviabilizou seu manuseio do PU3070. 2. Na fase II foram confeccionadas chapas com fibras de Pinus caribaea e Eucalyptus grandis com uma nova síntese de adesivo, denominada neste trabalho de PU7030. A caracterização física e mecânica determinou valores de resistências compatíveis com as exigências da EMB. Entretanto, verificou-se a necessidade de se ajustar o teor de umidade a temperatura e a pressão de prensagem. 3. Na fase III novas chapas foram confeccionadas com fibras de Pinus caribea e Eucalyptus grandis modificando-se o teor de umidade, a temperatura e a pressão de prensagem. Com o resultado da caracterização física e mecânica, observou-se que as alterações nas umidades, temperatura e pressão de prensagem propiciaram resistências compatíveis com a EMB, com vantagens de utilização de menores teores de PU7030 e diminuição na temperatura de prensagem, representando economia no consumo de energia. Outro aspecto muito importante estudado neste trabalho foi a caracterização das chapas utilizando ensaios não-destrutivos. Neste caso foram realizadas medições, por meio de equipamento de ultra-som, utilizando-se transdutores de faces exponenciais e planas aplicados nas direções x, y e z das chapas. A partir das medições dos tempos de propagação das ondas ultra-sônicas determinaram-se as velocidades das ondas e as constantes dinâmicas das chapas. Estas variáveis foram comparadas com as propriedades de resistência das chapas obtidas nos ensaios estáticos. Em seguida desenvolveu-se análise estatística buscando-se avaliar as correlações entre os resultados de ensaios não-destrutivos e destrutivos tendo sido possível concluir que a utilização dos métodos de ensaios não-destrutivos é viável para inferir sobre as propriedades físicas e mecânicas das chapas. Com relação à utilização da PU7030, concluiu-se que essa poliuretana possibilita a substituição da resina fenólica na confecção das chapas MDF / Abstract: While employing low cost reforestation lumber, the technologies of the fabrication of fiber plates denominated ¿Medium Density Fiberboard¿ (MDF) offer to several industrial sectors the opportunity to aggregate worth to species with little or no commercial interest, opening to them the possibility of promising profitable investments. However, the phenolic resins used in the production of MDF plates are well-known pollutants to the environment and therefore harmful to the human beings in such a way that environmentally friendly alternatives have been eagerly sought. According to that, the present work has been aimed to evaluate the physical, chemical and mechanical properties of MDF manufactured with Polyurethane Adhesive (PU) derived from Castor Oil, due to the low toxicity and to the non-polluting characteristics of the resulting adhesive. The characterization of the plates has been accomplished with the help of Steinkamp BP7 ultrasonic equipment using 45 kHz transducers and the physical and mechanical tests recommended by Euro MDF Board - EMB. The work has been developed along three distinct phases. Initially a better understanding of the characteristics of the polyurethane adhesive derived from castor oil has been acquired. It has been learnt that the adhesive exhibits the main characteristic of a monocomponent synthesis, stabilized by air humidity. During that phase, plates with 5% and 10% of polyurethane adhesive have been manufactured, called Adhesive PU3070 in this work, corresponding to 30% of solids and 70% of solvents. The properties of the plates manufactured with this synthesis have been determined and it has been found that although they have met EMB demands, the strong exhalation of solvent has ruled out its usage for MDF manufacture. As for the second phase, fiber plates have been produced with a new synthesis, called Adhesive PU7030, that is, 70% of solids and 30% of solvents. Again mechanical properties have satisfied EMB regulations. However, during the tests, it has been noticed that in order to control the quality of the final product, a fine adjusting to the values of some important Variables in the manufacture process, such as humidity level, temperature and pressing pressure, would be necessary. Accordingly, in the last phase, using Pinus caribea as fiber material, three experimental conditions have been elaborated, one for each controlled Variable, and repeated again for Eucalyptus gandis. Resulting from the adjusting of the variables, it has been observed that during the manufacture process, plates using much less adhesive than the former standards still have satisfied EMB demands fully, with advantages of a significant decrease in the pressing temperature and the corresponding energy savings. The characterization of the plates using non-destructive tests has been an important feature of the present work. Measurements have been performed in the plates by means of ultrasound equipment, using exponential as well as plane face transducers. From the readings, the propagation times of the ultrasonic waves have been evaluated, allowing to the determination of the propagation velocity of the ultrasonic waves through the material and consequently its dynamic parameters, which have been correlated to the mechanical properties of the plates, by means of a suitable statistic model. It has been concluded from the results that non-destructive test methods could as well be employed for the characterization of the physical and mechanical properties of the plates / Doutorado / Construções Rurais / Doutor em Engenharia Agrícola
48

Exploring design-driven innovation : A study on value creation by SMEs in the Swedish wood products industry

De Goey, Heleen January 2017 (has links)
Design-driven innovation, focused on the innovation of product meanings, provides a new perspective to better understand the contribution of design to innovation. Additionally, it enables new opportunities for value creation. At small and medium-sized enterprises (SMEs) in the Swedish wood products industry there is a need for such new value creation in order to remain competitive. However, design-driven innovation is not yet common in this context. Furthermore, there is little research on the innovation of product meanings focused on value creation. Therefore, the aim of this research is to explore value creation through design-driven innovation, in the context of SMEs in the Swedish wood products industry. This research addresses what value might be expected from design-driven innovation, as well as what enables and hinders this value creation.  To address the aim, three studies have been conducted which are described in four appended papers. The studies consist of one systematic literature review and two case studies. The findings demonstrate that design-driven innovation contributes to value creation by focusing on product meanings, which intentionally addresses both tangible and intangible needs and therefore increases the perceived value of products. This research identified five facets of design-driven innovation which provide a structure to discuss what enables and hinders value creation. These are: (1) understanding new product meanings, (2) knowledge generation, (3) actors and collaborations, (4) capabilities, and (5) process. The facets can be seen as the origin of both enablers and barriers to value creation through design-driven innovation, depending on how they are addressed. Moreover, this research suggests that whether or not value is created is further influenced by the SMEs, their networks and the context in which they operate.
49

Biogeochemistry of Carbon on Disturbed Forest Landscapes

Amichev, Beyhan Y. 11 May 2007 (has links)
Carbon accreditation of forest development projects is essential for sequestering atmospheric CO2 under the provisions of the Kyoto Protocol. The carbon sequestration potential of surface coal-mined lands is not well known. The purpose of this work was to determine how to measure carbon sequestration and estimate the additional amount that could be sequestered using different reforestation methods compared to the common practice of establishing grasslands. I developed a thermal oxidation technique for differentiating sequestered soil carbon from inorganic and fossilized carbon found at high levels in mine soils along with a geospatial and statistical protocol for carbon monitoring and accounting. I used existing tree, litter, and soil carbon data for 14 mined and 8 adjacent, non-mined forests in the Midwestern and Eastern coal regions to determine, and model sequestered carbon across the spectrum of site index and stand age in pine, mixed, and hardwood forest stands. Finally, I developed the framework of a decision support system consisting of the first iteration of a dynamic model to predict carbon sequestration for a 60-year period for three forest types (white pine, hybrid poplar, and native hardwoods) at three levels of management intensity: low (weed control), medium (weed control and tillage) and high (weed control, tillage, and fertilization). On average, the highest amount of ecosystem carbon on mined land was sequestered by pine stands (148 Mg ha-1), followed by hardwood (130 Mg ha-1) and mixed stands (118 Mg ha-1). Non-mined hardwood stands contained 210 Mg C ha-1, which was about 62% higher than the average of all mined stands. After 60 years, the net carbon in ecosystem components, wood products, and landfills ranged from 20 to 235 Mg ha-1 among all scenarios. The highest net amount of carbon was estimated under mixed hardwood vegetation established by the highest intensity treatment. Under this scenario, a surface-mined land of average site quality would sequester net carbon stock at 235 Mg C ha-1, at a rate of 3.9 Mg C ha-1 yr-1, which was 100% greater than a grassland scenario. Reforestation is a logical choice for mined land reclamation if carbon sequestration is a management objective. / Ph. D.
50

Lean Management: Awareness, Implementation Status, and Need for Implementation Support in Virginia's Wood Industry

Fricke, Christian 12 January 2011 (has links)
During the last decades, the U.S. wood products (NAICS 321) and furniture manufacturing (NAICS 337) industries have been greatly affected by economic cycles, rising production and transportation costs, changing buyer habits, and, arguably, most powerfully, increasing global competition. As a result, tens of thousands of jobs were lost and a large number of companies in the industry experienced bankruptcy, closed operations, or relocated to other countries. However, theories exist stating that the use of management systems, such as, for example, Lean management, allows companies to become more competitive and enhance the likelihood of survival. A mail survey was conducted to investigate companies in Virginia's wood products and furniture manufacturing industries as to their awareness of Lean management, the implementation of Lean practices, as well as the companies' need for support in Lean implementation efforts. Findings indicate that a majority of Virginia's wood products and furniture manufacturing industries have heard about terms like, for example, Lean management, Lean manufacturing, or Lean thinking, but are rarely aware of individual Lean elements of which Lean consists. Few businesses thus have implemented Lean. However, findings show that Lean awareness and Lean implementation status differs between individual industry sub-segments. The group of industry segments with the highest Lean awareness and Lean implementation status were "engineered wood products," "manufactured homes," and "household furniture manufacturing," as opposed to industry sub-segments such as "sawmill" and "wood container and pallets," which had lower Lean awareness and Lean implementation status. The study also revealed that smaller companies (less than 50 employees) have a lower level of Lean awareness and implementation status than do larger companies (50-499 employees). Despite the low level of Lean implementation across the wood products and furniture manufacturing industry in Virginia, less than one-fourth of all respondents indicated a need for Lean implementation support. / Master of Science

Page generated in 0.0701 seconds