1000 resultados para forest machines


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The report presents the results of the commercialization project called the Container logistic services for forest bioenergy. The project promotes new business that is emerging around overall container logistic services in the bioenergy sector. The results assess the European markets of the container logistics for biomass, enablers for new business creation and required service bundles for the concept. We also demonstrate the customer value of the container logistic services for different market segments. The concept analysis is based on concept mapping, quality function deployment process (QFD) and business network analysis. The business network analysis assesses key shareholders and their mutual connections. The performance of the roadside chipping chain is analysed by the logistic cost simulation, RFID system demonstration and freezing tests. The EU has set the renewable energy target to 20 % in 2020 of which Biomass could account for two-thirds. In the Europe, the production of wood fuels was 132.9 million solid-m3 in 2012 and production of wood chips and particles was 69.0 million solidm3. The wood-based chips and particle flows are suitable for container transportation providing market of 180.6 million loose- m3 which mean 4.5 million container loads per year. The intermodal logistics of trucks and trains are promising for the composite containers because the biomass does not freeze onto the inner surfaces in the unloading situations. The overall service concept includes several packages: container rental, container maintenance, terminal services, RFID-tracking service, and simulation and ERP-integration service. The container rental and maintenance would provide transportation entrepreneurs a way to increase the capacity without high investment costs. The RFID-concept would lead to better work planning improving profitability throughout the logistic chain and simulation supports fuel supply optimization.

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Demand for increased energy efficiency has put an immense need for novel energy efficient systems. Electrical machines are considered as a much matured technology. Further improvement in this technology needs of finding new material to incorporate in electrical machines. Progress of carbon nanotubes research over the latest decade can open a new horizon in this aspect. Commonly known as ‘magic material’, carbon nanotubes (CNTs) have promising material properties that can change considerably the course of electrical machine design. It is believed that winding material based on carbon nanotubes create the biggest hope for a giant leap of modern technology and energy efficient systems. Though carbon nanotubes (CNTs) have shown amazing properties theoretically and practically during the latest 20 years, to the best knowledge of the author, no research has been carried out to find the future possibilities of utilizing carbon nanotubes as conductors in rotating electrical machines. In this thesis, the possibilities of utilizing carbon nanotubes in electrical machines have been studied. The design changes of electrical machine upon using carbon nanotubes instead of copper have been discussed vividly. A roadmap for this carbon nanotube winding machine has been discussed from synthesis, manufacturing and operational points of view.

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Studies of plant community dynamics are essential in understanding the demographic patterns of species since changes in demographic rates can affect the floristic composition and future structure. The purpose of the present study was to analyze the changes in the community structure and floristic composition of woody plants in a tropical semi-deciduous forest in Uberlândia in central Brazil, during a 10-years period. The data were collected in 1989 and in 2000 in 50 quadrats (10 m x 10 m) where all trees with a minimum circumference at breast height of 10 cm were sampled. In 1989, 93 species and 1103 individuals were registered. Over a period of 10 years, seven new species were added to the community, although eight disappeared. The main change that occurred during this period in the floristic composition was the replacement of savannah species occurring in forest gaps by those from the forest understory.

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In this study we evaluated photosynthetic characteristics and patterns of biomass accumulation in seedlings of two tree species from a Semideciduous Tropical Forest of Brazil. Seedlings of Trema micrantha (L.) Blum. (pioneer) and Hymenaea courbaril (L.) var. stilbocarpa (Hayne) Lee & Langenh. (climax) were grown for 4 months under low light (LL) (5%-8% of sunlight) and high light (HL) (100% of sunlight). Under HL, T. micrantha showed higher CO2 assimilation rates (A CO2) and light saturation than H. courbaril. Under LL, A CO2 were higher in H. courbaril. Under LL, total chlorophyll and carotenoid contents per unit leaf area were higher in H. courbaril. Chlorophyll a/b ratio was higher in T. micrantha under both light regimes. A CO2 and Fv/Fm ratio at both pre-dawn and midday in H. coubaril were lower in HL indicating chronic photoinhibition. Thus, the climax species was more susceptible to photoinhibition than the pioneer. However, H. courbaril produced higher total biomass under both treatments showing high efficiency in the maintenance of a positive carbon balance. Thus, both species expressed characteristics that favor growth under conditions that resemble their natural microenvironments, but H. courbaril also grew under HL. The ecophysiological range of responses to contrasting light levels of this climax plant seems to be broader than generally observed for other rainforest climax species. We propose that this could be related to the particular spatio-temporal light regime of the semideciduous forests.

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The population structure of a common canopy tree was examined in three sites to investigate the possible effects of forest fragmentation in eastern Amazonia. Evidence for the escape hypothesis of differential seed/seedling survival was evaluated. Two 1 ha plots were established at each site and all individuals of Eschweilera coriacea (DC.) S. A. Mori over 1 m tall were tagged, measured and mapped. Smaller individuals were recorded in the same way within subplots. Mature individuals were abundant at all sites with densities of 32-52 ha-1. The species exhibited substantial regeneration, although total population density varied fourfold among sites (1,256-4,805 individuals ha-1). Overall, juveniles were clumped while adults were randomly distributed. The difference between the dispersion pattern of adults and juveniles supported the escape hypothesis. However, no difference in population structure among sites could be related to the forest fragmentation.

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The objective of this study was to analyze the floristic composition and structure of the tree component in a seasonally deciduous forest on limestone outcrops, located in the northeast region of Goiás State, Brazil. A sample composed of 25 randomly sampled plots of 20 x 20 m (400 m²) within a 50 ha forest, was measured. All woody individuals > 5 cm diameter at breast height (DBH) had their diameter and height measured. The tree community was composed of 39 species with a density of 734 individuals ha-1; the richest families were Leguminosae (11 species), Bignoniaceae (4 species) and Apocynaceae (4 species). The forest had a basal area of 16.37 m² ha-1, with the most important species Cavanillesia arborea (3.26 m² ha-1), Pseudobombax tomentosum (2.35 m² ha-1), Dilodendron bipinnatum (1.84 m² ha-1), Tabebuia impetiginosa (1.36 m² ha-1) and Myracrodruon urundeuva (1.26 m² ha-1) occupying 61.5% of the total basal area of the forest. Several species grew on rocks, or in rock fissures or in places with a shallow layer of soil or even in litter over rocky layers. The floristic composition showed links with the "Caatinga" flora, with other patches of seasonal forests in Central Brazil and in the Pantanal, and with the Chiquitano forests of Bolivia too, containing even two species considered as endemic to the "Caatinga".

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The family Rubiaceae comprises a wide spectrum of floral mechanisms and two of them seem to be common in certain groups, e.g., distyly in Rubioidae and styllar pollen in Ixoroidae. These mechanisms include herkogamy, which is interpreted as a strategy that avoids self-pollination. This is the first report on the reproductive biology of Chiococca alba, a species that is widely distributed in America. We studied floral biology and the mating system, which were evaluated through fruit set comparisons after controlled crosses (self- and cross-pollinations and test for apomixis), as well as through the evaluation of pollen tube growth resulting from these controlled crosses. Flowers of C. alba are herkogamous, cream, protandrous and lasted for two days. No measurable nectar was found, despite the presence of a nectary-like structure at the base of the corolla tube. Chiococca alba is a preferentially self-incompatible species, but self-pollination and apomixis also contribute to the natural fruit-set. Its reproductive strategy (herkogamy associated with protandry) is different from that expected for members of Chiococceae tribe (i.e., styllar pollen presentation).

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To understand the growth and reproduction of the palm Geonoma schottiana in the gallery forest of Central Brazil, two hypotheses were raised: (i) production of leaves and reproductive structures are concentrated in the period of the year with high light availability; (ii) leaf production and reproductive activity are related to plant length. However, it is expected that senility effects will cause fast reduction in growth and reproduction activities in higher plants. Growth and reproduction were concentrated in the dry season, when insolation is higher than in the wet season, suggesting that leaf and inflorescence production on G. schottiana in the gallery forest understory is more limited by light than by soil humidity. As the individual grows, leaf number and blade area increase, but reproduction activity is independent of plant length. Resources stored in the stem are important to growth, but exogenous factors, as canopy openness, should be more important to reproduction. Plant senescence seems to have a lesser effect on the production of vegetative and reproductive structures in G. schottiana than has been detected in congeneric species with greater clonal activity.

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We studied the community and habitat occupation of epiphytes to understand how these plants cope with a supposedly stressful habitat: i) how general epiphytes occupy tree trunks, ii) how epiphytic bromeliads, occupy their supportive trees, iii) how CAM bromeliads are spatially distributed. The study was done in the dry forest of Jacarepiá, State of Rio de Janeiro. Data collection on epiphytes, phorophytes, and trees was based on the point-center quarter method. The photosynthetic pathway of the bromeliad species was determined using isotope ratio mass spectrometry. The presence of Gesneriaceae, Araceae, and Cactaceae indicates that some humidity is present in the area allowing the presence of supposedly less-specialized epiphytes. There was no correlation between epiphyte abundance and phorophyte diameter, and phorophytes had larger sizes than trees that do not host epiphytes. There was correlation between tree diameter and bromeliad abundance, and lack of correlation between diameter and bromeliad richness. Only one species was typical of the understorey and one was typical of the canopy, while intermediate heights were occupied by different species. The only C3 bromeliad species (Vriesea procera (Mart. ex Schult.f.) Wittm.) was significantly more exposed than the other species. If CAM occurrence is related to water economy, the fact that a C3 species is subjected to more exposed conditions is remarkable. Further comments are presented on the proportion between CAM bromeliad species and abundance in dry forest. Regarding life forms, holoepiphytes, as opposed to hemiepiphytes, showed not to be restricted by the phorophyte's diameter suggesting a more successful establishment of this life form.

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Above-ground litter production is one of the most accessible ways to estimate ecosystem productivity, nutrient fluxes and carbon transfers. Phenological patterns and climatic conditions are still not fully explained well for tropical and subtropical forests under less pronounced dry season and non-seasonal climates, as well as the interaction of these patterns with successional dynamics. Monthly litterfall was estimated for two years in a 9 to 10 year old secondary alluvial Atlantic Rain forest. Total litterfall was higher in the site with more developed vegetation (6.4 ± 1.2 ton ha-1 year-1; 95% confidence interval) as compared to the site with less developed vegetation (3.0 ± 1.0 ton ha-1 year-1). The monthly production of 11 litter fractions (eight fractions comprising the leaf litter of the seven main species of the community and other species; reproductive parts, twigs £ 2 cm diameter, and miscellaneous material) were correlated with meteorological variables making possible to identify three patterns of deposition. The main pattern, dominated by leaf-exchanging species, consisted of a cycle with the highest litterfall at the beginning of the rainy season, preceding by basically three months the peaks of the annual cycles of rainfall and temperatures. Other two patterns, dominated by brevi-deciduous species, peaked at the end of the rainy season and at the end of the non-rainy season. Tropical and subtropical dry forests that present the highest leaf fall gradually earlier than rain forests (as the studied sites) are possibly related to the start of senescence process. It seems that such process is triggered earlier by a more severe hydric stress, besides other factors linked to a minor physiological activity of plants that result in abscission.

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The algae inhabit a wide variety of terrestrial environments and substrates; however the taxonomic knowledge for tropical regions is still scarce. This survey was conducted in ten forest remnants in São Paulo State where visible growths of algae and bryophytes were collected and studied for the main algal components of the communities. Results reveal the occurrence of nine species of green algae, distributed through the class Trebouxiophyceae (one species), Charophyceae (one species) and Ulvophyceae (seven species). Desmococcus olivaceus (Persoon ex Archerson) J. R. Laundon and Printzina effusa (Krempelhüber) Thompson & Wujek are new records for Brazil. The most frequent organisms found in the areas pertain to Trentepohliales that is mainly represented by Trentepohlia species. On the basis of results found, it is recommended that such communities receive more attention in future investigations to improve the knowledge about this important group of primary producers.

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Leaf CO2 assimilation (A) as a function of photosynthetic photon flux density (Q) or intercellular CO2 concentration (Ci) and chlorophyll fluorescence measurements were carried out on four tropical woody species growing in forest gap and understorey (Bauhinia forficata Link. and Guazuma ulmifolia Lam. as pioneers, and Hymenaea courbaril L. and Esenbeckia leiocarpa Engl. as non-pioneers). Chlorophyll fluorescence indicated similar acclimation capacities of photochemical apparatus to contrasting light environments irrespective to plant species. Maximum CO2 assimilation and quantum yield derived from A/Q curves indicated higher photosynthetic capacity in pioneer than in non-pioneer species in forest gap. However, the differences among species did not show a straightforward relation with their successional status regarding data derived from A/Q curves under understorey conditions. Both successional groups are able to sustain positive carbon balance under contrasting natural light availabilities, modifying photochemical and biochemical photosynthetic traits with similar phenotypic plasticity capacity.

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The aim of this study is to investigate the floristic composition of an Atlantic rain forest fragment located in Cananéia, São Paulo, Brazil, and to contribute to the knowledge on Atlantic forest through the comparative analysis of this and other floristic surveys both on the southern and southeastern Brazil, in different soil and relief types. We surveyed 215 species in 132 genera and 51 families. Classification and ordination analysis were applied to a binary matrix in order to analyze the similarity among 24 surveys, including the present one, of Atlantic forest from the south and southeast coast of Brazil. Higher floristic similarity was observed among this area and the ones where there was marine influence and more rugged relief. The surveys in areas with greater marine influence (sandy soil) were separated from those in other conditions, possibly indicating a species replacement gradient from the steep slopes towards the lowland and were probably related to different edaphic conditions. A latitudinal gradient was found among the surveys apparently confirming a continuous species replacement along the Atlantic forest, related to a restricted distribution of the species. This suggests that it is essential to preserve areas from the whole Atlantic coast. Atlantic forest distribution is quite complex and its composition cannot be adequately represented by small localized areas.

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This master’s thesis was done for a small company, Vipetec Oy, which offers specialized technological services for companies mainly in forest industry. The study was initiated partly because the company wants to expand its customer base to a new industry. There were two goals connected to each other. First was to find out how much and what kind of value current customers have realized from ATA Process Event Library, one of the products that the company offers. Second was to determine the best way to present this value and its implications for future value potential to both current and potential customers. ATA helps to make grade and product changes, starting after machine downtime, and recovery from production break faster for customers. All three events sometimes occur in production line. The faster operation results to savings in time and material. In addition to ATA Vipetec also offers other services related to development of automation and optimization of controls. Theoretical part concentrates on the concept of value, how it can be delivered to customers, and what kind of risk customer faces in industrial purchasing. Also the function of reference marketing towards customers is discussed. In the empirical part the realized value for existing customers is evaluated based on both numerical data and interviews. There’s also a brief case study about one customer. After that the value-based reference marketing for a target industry is examined through interviews of these potential customers. Finally answers to the research questions are stated and compared also to the theoretical knowledge about the subject. Results show that those customers’ machines which use the full service concept of ATA usually are able to save more time and material than the machines which use only some features of the product. Interviews indicated that sales arguments which focus on improved competitive status are not as effective as current arguments which focus on numerical improvements. In the case of potential customers in the new industry, current sales arguments likely work best for those whose irregular production situations are caused mainly by fault situations. When the actions of Vipetec were compared to ten key elements of creating customer references, it was seen that many of them the company has either already included in its strategy or has good chances to include them with the help of the results of this study.

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Aulonemia aristulata (Döll) McClure is a lignified bamboo species endemic to Brazil. This species occurs in southeastern forests and can reach high density at forest edges, dominating the understory of canopy-disturbed forest patches. The goal of this study was to describe the flowering period, floral biology, fruiting and seedling recruitment of A. aristulata in natural conditions in two areas located in a segment of the Atlantic Forest. Data on the morphology of the synflorescences and florets, timing and sequence of the anthesis events and floral visitors were recorded. Natural pollinators (open pollination or control) as well as spontaneous self-pollination were also checked. Pollen viability was estimated using the acetocarmine technique. Aulonemia aristulata is monocarpic (semelparous) with gregarious flowering. All culms in both studied areas blossomed and fruited between August and November 2007, dying subsequently between December 2007 and April 2008. Two types of synflorescences and flowers were observed: terminal with bisexual and protandric florets, with the anthesis lasting for 3-4 days; and axillary, with morphologically bisexual, but functionally female, florets and anthesis lasting for 3-4 days. The latter were also observed in the rhizome of plants whose aerial portion had been removed. The presence of axillary synflorescences with pistillate flowers is described here for the first time in Aulonemia species. Moreover, this is the first report of gynomonoecy in woody bamboo. Fruiting from bisexual florets under natural conditions (35%) was superior to that obtained from bagged synflorescences (11.5%). Fruiting from functional female florets was around 20%. Pollen viability was on the average of 90%. The results suggest that Aulonemia aristulata is anemophilous. The massive bamboo seedling recruitment observed after dieback with the ability to colonize open areas could promote the regeneration of Aulonemia aristulata.