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An examination of the current slope gradients being experienced by ground-based forest machines in New Zealand plantation forests.Berkett, Hamish January 2012 (has links)
Harvesting is typically one of the largest cost components within a plantation forest rotation. A large proportion of New Zealand’s future harvest will be on steep terrain. Currently steep terrain harvesting is characterised by lower productivity and higher cost. It also has higher levels of manual or motor manual tasks such as setting chokers or tree felling, with a corresponding higher safety risk. The utilisation of ground-based machines on steep terrain has the potential to decrease harvest costs and improve safety. There is currently a push in New Zealand to increase the operating range. This is being done with a poor understanding of the slopes on which machines are currently operating and little understanding of the new risks steeper slopes might introduce. To better understand the true range of slopes on which forest machines are operating, a digital accelerometer was attached to 22 forest machines and provided real-time measurements of slope. The evaluated machines were grouped into one of four machine types; felling (n=4), shovelling (n=5), skidder (n=9) or European (n=4). The machine types were then analysed with respect to their machine slope (actual) and terrain slope (predicted) based on a digital terrain map. Two methods of calculating terrain slope were used, method one was based on a triangular irregular network (TIN) file with method two based off a raster file. Linear regression indicated that there was a relationship between machine slope and terrain slope for all four machine types, with the exception of European based machines, using the TIN method of slope calculation. All variables showed a poor coefficient of determination with the highest adjusted R squared single variable explaining 17% of the variation. All machines operated on slopes that exceed the New Zealand approved code of practice guideline of 30% and 40% slope for wheeled and tracked machines respectively. New Zealand based machines were shown to exceed the guidelines for terrain slope much more frequently, and by a greater margin, than European based machines.
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Совершенствование анализа финансового состояние коммерческой организации : магистерская диссертация / Improving the analysis of the financial condition of a commercial organizationХоу, С., Hou, X. January 2018 (has links)
As economic development, the financial analysis of the company's economic activities becomes an integral part of the strategic development of the enterprise. To clarify the situation on financial statements, companies use different methods and indicators to analyze the activity. Thus, to date, the analysis of the financial and economic activities of the enterprise does not analyze the external environment, which may adversely affect the results of the analysis and, accordingly, the planning of the enterprise. Now there are a number of non-traditional methods for analyzing the external environment of an enterprise in conjunction with internal analysis. In the dissertation SWOT and STEEP kinds of analyzes are applied at the analysis of financial and economic activity of the enterprise that gives the chance to see effect from activity of the company in the market and to reveal a direction of development of activity for increase of efficiency. Practical significance is that the results of the study can be used to improve the analysis of the financial situation of a commercial organization. / По мере экономического развития, финансовый анализ хозяйственной деятельности компании становится неотъемлемой составляющей стратегического развития предприятия. Чтобы прояснить ситуацию по финансовой отчетности компании используют различные методы и показатели для анализа деятельности. Таким образом, на сегодняшний день анализ финансово-хозяйственной деятельности предприятия не анализирует внешнюю среду, что может отрицательно сказаться на результатах анализа и, соответственно, на планирование деятельности предприятия. Сейчас существуют ряд нетрадиционных методов анализа внешней среды предприятия в совокупности с внутренним анализом. В диссертации применены SWOT и STEEP виды анализов при анализе финансово-хозяйственной деятельности предприятия, что дает возможность увидеть эффект от деятельности компании на рынке и выявить направление развития деятельности для повышения эффективности. Практическая значимость состоит в том, что результаты проведенного исследования могут быть использованы совершенствование анализа финансового состояние коммерческой организации.
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Continuous production of succinic acid with Actinobacillus succinogenes biofilms: Effect of complex nitrogen source on yield and productivityVijayan, Uma Rajendra Prasad January 2016 (has links)
Continuous fermentations were performed in an external-recycle, biofilm reactor using glucose and CO2 as carbon substrates. The nitrogen source for the auxotrophic Actinobacillus succinogenes was a combination of yeast extract (YE) and corn steep liquor (CSL), and sometimes only YE or CSL was used.
In this study, the succinic acid productivity of A. succinogenes decreased by 67% as the amount of YE in the complex nitrogen source mixture decreased from 16 g·L-1 to 0 g·L-1. Succinic acid production increased as the CSL concentration in the nitrogen source increased, and the mass ratio of succinic acid to acetic acid exceeded the theoretical maximum limit of 3,93 g·g-1 when only CSL was used as the nitrogen source. The mass ratio of formic acid to acetic acid was consistently within the theoretical yield limitations (0,77 g·g−1) and decreased as the CSL concentration in the nitrogen source increased. The highest SA concentration in this study was 22,57 g·L-1 when only YE was used as the nitrogen source in the growth medium, and the highest SA productivity obtained in this study was 1,58 g·L-1·h-1 when a combination of YE and CSL was used as a nitrogen source. The highest mass ratio of SA to AA achieved was 8,3 g·g-1 when CSL was the sole nitrogen source. The mass ratio of FA to AA was consistently less than 0,77 g·g-1, approaching 0 g·g-1, as the CSL concentration in the nitrogen source increased. / Dissertation (MSc)--University of Pretoria, 2016. / National Research Foundation (NRF) / Chemical Engineering / MSc / Unrestricted
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Využití finančních a ekonomických ukazatelů v podniku. / Use of Financial and Economic Indexes in Company.Chromčík, Tomáš January 2010 (has links)
This thesis deals with the use of financial and economic indicators in the business. The thesis focuses on assessing business performance based on economic and financial indicators and is primarily based on the balance of financial statements and profit and loss report. The thesis presents suggestions and steps to improve business performance.
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Channel form, flow and sediment transport in a step-pool streamDudley, John Richard January 2007 (has links)
The influence of channel morphology and hydraulics on sediment transport within steep upland streams is investigated. Step-pools are the most common bedform in such streams. Bedload transport processes operating in a perennial step-pool stream in central England are established using magnetically-tagged particles and bedload pit samplers. Water-surface slope in two step-pool streams is monitored in detail. Water-surface slope measurements show that step-pool bedforms cause large spatial variations in flow depth during floods, and that the temporal variation of watersurface slope during a flood wave differs diametrically from the pattern found in lowgradient rivers that have little roughness. These results demonstrate that it is difficult to estimate the forces acting on the streambed in steep, rough streams and, therefore, conventionally established flow variables cannot be used to predict bedload transport . rates in step-pool channels. Particle tracing experiments are used to determine the control that step-pool morphology and flow hycfraulics have on particle displacements. Step-pool streams exhibit smaller particle travel distance per flood event than low-gradient rivers. This difference reflects the greater flow resistance and bed rugosity of step-pool streams. Bed morphology dictates flood particle displacement at step-pool bedform scale. It is shown that entrainment, pool export rates and transport distances of coarse sediment are dependent on downstream step dimensions, step permeability and pool form. Large variations in bedload transport rates at any given flow strength are associated with variable sediment supply, and particle tracing demonstrates that sediment availability is controlled at unit pool scale. Bedload consists of fine gravel moving over a stable bed surface at low discharges, while, at higher discharges, bedload coarsens, approaching the size of the pool bed material as the bed surface is partially mobilized. Step framework clasts are stable features of the streambed. Results from this study are incorporated into a descriptive model of discharge-related bedload transport phases in step-pool streams.
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John Hartwell Cocke (1780-1866): From Jeffersonian Palladianism to Romantic Colonial Revivalism in Antebellum VirginiaRogers, Muriel Brine 01 January 2003 (has links)
John Hartwell Cocke was a Virginia planter and amateur architect whose style evolved from Jeffersonian Classicism to a revival of English Tudor-Stuart or Jacobethan architecture. This dissertation discusses the Cocke family's Elizabethan roots and advances four theses. The first of these theses is that John Hartwell Cocke implemented Thomas Jefferson's principles for the reform of Virginia architecture. Cocke's most ambitious project, a Jeffersonian Palladian mansion called Bremo, was in the planning stages by 1815. The second thesis is that Cocke's off-plantation buildings signals his break from the Palladianism of Thomas Jefferson in favor of the Jacobean style for his houses and his acceptance of classical Jeffersonian elements for public buildings. The third thesis proposes John Hartwell Cocke as the first practitioner of the Romantic Colonial Revival movement in America in his revival of Tudor-Stuart architecture. The fourth thesis is that John Hartwell Cocke's architectural legacy was expanded by Philip St. George Cocke, the second of his three sons, when the younger Cocke commissioned Alexander J. Davis to build Belmead and later promoted Davis among his circle of family and friends.
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Faixas adicionais para trechos de rodovias com declives longos considerando os aspectos técnicos da frenagem de veículos de carga / Additional tracks for roads with long stretches of slopes considering the technical aspects of braking cargo vehiclesLucas, Manuel de Jesus 18 June 2004 (has links)
Esta dissertação de mestrado apresenta uma proposta de critério para a construção de faixas adicionais em rodovias com longos declives. A proposta contempla três aspectos: 1-) Elaboração de um programa de computador que permita calcular a temperatura do sistema de freios de qualquer veículo que esteja operando em qualquer ponto de uma rampa descendente, conhecidas as características do veículo, da massa transportada, da velocidade desenvolvida pelo veículo e da rampa em questão (comprimento e declividade). Em outras palavras: o programa permite gerar as curvas de desempenho para qualquer veículo de carga, em qualquer trecho de descida de uma rodovia; 2-) Determinação da redução de velocidade para caminhões nos trechos estudados; e 3-) Cálculo da porcentagem de veículos de carga no fluxo total de veículos que utilizam a rodovia, valor esse que viabilize economicamente a construção de faixas auxiliares. Esta dissertação aborda mais profundamente o primeiro aspecto da proposta. Os outros dois, devido à sua complexidade, são sugeridos como tema para trabalhos futuros. De posse do programa computacional, o mesmo foi utilizado para simular o comportamento da frota de veículos de carga brasileiros, em greides com comprimento variável de 1.000 a 12.000 metros e inclinações que variam de 1 a 12%. Também foi verificado o impacto da aplicação da resolução 777/93 do CONTRAN - que regulamenta o desempenho e o sistema de freios dos veículos de carga - na frota brasileira de veículos de carga. Os resultados obtidos indicam, além da importância de uma legislação adequada para o tema, uma urgente renovação ou adequação da frota brasileira de veículos de carga, haja visto que grande parte da mesma, por possuir uma elevada idade média, não atinge os requisitos mínimos para circular pelas rodovias brasileiras sem comprometimento das condições de segurança, dirigibilidade, estabilidade e desempenho. / This master thesis presents a criteria\'s proposal to construction of auxiliary lanes in roads with long and steep downgrades. The proposal contemplates three aspects: 1-) Elaboration of a computer\'s program that allows to obtain the brake system\'s temperature of any heavy truck performing at any point of a long and steep downgrade. It\'s necessary to know the truck\'s brake characteristics, the brake-motor power, the total mass transported, the vehicles\'speed and the downhill characteristics (length and percent). With this data, the program calculates the performance curves of brazilian trucks, regarding brakes\'system\'s termical aspects; 2-) Determination of the maximum speed reduction of slow trucks on downhill; and, 3-) Estimation of minimum downgrade traffic flow rates and truck percents that would warrant the construction of declivity help lanes, from costs-effectiveness approach. This master thesis broaches more profundity the first proposal\'s aspects. The aspects two and three, due to its complexity, are suggested to be future studies\'object. The computational program developed in this work was used to simulate the performance of brazilian\'s fleet heavy truck in declivities with lengths from 1.000 till 12.000 meters and declivity that vary from 1 till 12%. It was used, too, to show the impact of the resolution number 777/93 - edited by CONTRAN - applicated in the same fleet. This resolution rules ship vehicles\'brakes\'system and their performance. The obtain results denote, farther importance of a adequate legislation for the theme, a urgent renovation or adequation of brazilian\'s fleet heavy truck due to, a large part of it, with more than ten year of age, is unable to reach the minimum requisites to moving on brazilian roads and highways without implication of security, conductibility, stability and performance\'s conditions.
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Cultivo de Scenedesmus acuminatus em água de maceração do milho e extração e quantificação de lipídeos / Culture of scenedesmus acuminatus in corn steep liquor and extraction and lipid quantificationTomas, Cristiane 29 August 2016 (has links)
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Previous issue date: 2016-08-29 / The search for renewable energy sources is a concern of the new generations in face of possible fossil fuel scarcity and climate change caused by greenhouse gas emissions. When compared with diesel derived from petroleum, the biodiesel can reduce 78% carbon dioxide emissions, considering plants reabsorption; also, it can reduce by 90% emissions of smoke and virtu ally eliminates sulfur oxide. The purpose of this research was to investigate the cultivation of microalgae Scenedesmus acuminatus in the substrate composed by corn steep liquor for biodiesel production purposes. Initially a preliminary test was carried out to verify the viability of growing the microalgae in the effluent; further, a central composite design was carried to study the influence of the effluent and inoculum concentration on the cell density biomass, production of biomass, chemical oxygen demand (COD) and maximum growth rate (μmax) of microalgae culture. Statistical analysis indicated that the percentage of inoculum and effluent had na influence on the cell density, COD and maximum specific growth rate and that the optimal cultivation conditions would be achieved with the use of 53.5 % of efluente and 5.2% of inoculum. The proposed model was validated through cultivation under the proposed conditions, achieving 0.30 g/L of dry biomass on the seventh day. The cultivation, together with the coagulation procedure, was efficient for the removal of organic matter, verified through the COD and pH reduction, reaching the appropriate level according the standard required by current legislation. HARA & RADIN (1978) was more efficient for extraction at 45ºC: achieved a yield of 44,50 ± 2,12 mg / L total lipids. The extraction temperature had influence on the yield of lipids: the procedure performed at 45 ° C was able to extract more lipids in both methods. / A busca por fontes renováveis de energia é uma preocupação das novas gerações em face da possível escassez dos combustíveis fósseis e das alterações climáticas causadas pelas emissões dos gases do efeito estufa. Comparado ao óleo diesel derivado de petróleo, o biodiesel pode reduzir em 78% as emissões de gás carbônico, considerando-se a reabsorção pelas plantas; também reduz em 90% as emissões de fumaça e praticamente elimina as emissões de óxido de enxofre. O objetivo desta pesquisa foi investigar o cultivo de microalgas Scenedesmus acuminatus em substrato composto por água de maceração do milho para fins de produção de biodiesel. Inicialmente realizou-se um teste preliminar para verificar a viabilidade de crescimento dessa microalga no efluente; posteriormente foi realizado um delineamento composto central rotacional para estudar a influência da concentração de efluente no meio e percentual inicial de células (inóculo) sobre a densidade celular, acúmulo de biomassa, DQO e velocidade máxima de crescimento (μmax) do cultivo. A análise estatística indicou que os percentuais de inóculo e efluente tiveram influência sobre a densidade celular, DQO e velocidade máxima específica de crescimento e que as condições ótimas do cultivo seriam alcançadas com a utilização de 53,5% de efluente e 5,2% de inóculo. O modelo proposto foi validado através de um cultivo nas condições propostas, cujo rendimento em biomassa seca foi de 0,30g/L ao sétimo dia. O cultivo, aliado ao procedimento de coagulação, foi eficiente para remoção de matéria orgânica do meio de cultura, observada através da redução dos valores de DQO e pH, que atingiram nível adequado ao padrão exigido pela legislação vigente. A metodologia HARA & RADIN (1978) foi a mais eficiente foi mais eficiente para extração de lipídeos totais à temperatura de 45ºC: obteve um rendimento de 44,50 ± 2,12 mg/L. A temperatura de extração teve influência sobre o rendimento em lipídeos: o procedimento realizado a 45°C foi capaz de extrair maior quantidade de lipídeos para ambos os métodos.
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Faixas adicionais para trechos de rodovias com declives longos considerando os aspectos técnicos da frenagem de veículos de carga / Additional tracks for roads with long stretches of slopes considering the technical aspects of braking cargo vehiclesManuel de Jesus Lucas 18 June 2004 (has links)
Esta dissertação de mestrado apresenta uma proposta de critério para a construção de faixas adicionais em rodovias com longos declives. A proposta contempla três aspectos: 1-) Elaboração de um programa de computador que permita calcular a temperatura do sistema de freios de qualquer veículo que esteja operando em qualquer ponto de uma rampa descendente, conhecidas as características do veículo, da massa transportada, da velocidade desenvolvida pelo veículo e da rampa em questão (comprimento e declividade). Em outras palavras: o programa permite gerar as curvas de desempenho para qualquer veículo de carga, em qualquer trecho de descida de uma rodovia; 2-) Determinação da redução de velocidade para caminhões nos trechos estudados; e 3-) Cálculo da porcentagem de veículos de carga no fluxo total de veículos que utilizam a rodovia, valor esse que viabilize economicamente a construção de faixas auxiliares. Esta dissertação aborda mais profundamente o primeiro aspecto da proposta. Os outros dois, devido à sua complexidade, são sugeridos como tema para trabalhos futuros. De posse do programa computacional, o mesmo foi utilizado para simular o comportamento da frota de veículos de carga brasileiros, em greides com comprimento variável de 1.000 a 12.000 metros e inclinações que variam de 1 a 12%. Também foi verificado o impacto da aplicação da resolução 777/93 do CONTRAN - que regulamenta o desempenho e o sistema de freios dos veículos de carga - na frota brasileira de veículos de carga. Os resultados obtidos indicam, além da importância de uma legislação adequada para o tema, uma urgente renovação ou adequação da frota brasileira de veículos de carga, haja visto que grande parte da mesma, por possuir uma elevada idade média, não atinge os requisitos mínimos para circular pelas rodovias brasileiras sem comprometimento das condições de segurança, dirigibilidade, estabilidade e desempenho. / This master thesis presents a criteria\'s proposal to construction of auxiliary lanes in roads with long and steep downgrades. The proposal contemplates three aspects: 1-) Elaboration of a computer\'s program that allows to obtain the brake system\'s temperature of any heavy truck performing at any point of a long and steep downgrade. It\'s necessary to know the truck\'s brake characteristics, the brake-motor power, the total mass transported, the vehicles\'speed and the downhill characteristics (length and percent). With this data, the program calculates the performance curves of brazilian trucks, regarding brakes\'system\'s termical aspects; 2-) Determination of the maximum speed reduction of slow trucks on downhill; and, 3-) Estimation of minimum downgrade traffic flow rates and truck percents that would warrant the construction of declivity help lanes, from costs-effectiveness approach. This master thesis broaches more profundity the first proposal\'s aspects. The aspects two and three, due to its complexity, are suggested to be future studies\'object. The computational program developed in this work was used to simulate the performance of brazilian\'s fleet heavy truck in declivities with lengths from 1.000 till 12.000 meters and declivity that vary from 1 till 12%. It was used, too, to show the impact of the resolution number 777/93 - edited by CONTRAN - applicated in the same fleet. This resolution rules ship vehicles\'brakes\'system and their performance. The obtain results denote, farther importance of a adequate legislation for the theme, a urgent renovation or adequation of brazilian\'s fleet heavy truck due to, a large part of it, with more than ten year of age, is unable to reach the minimum requisites to moving on brazilian roads and highways without implication of security, conductibility, stability and performance\'s conditions.
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Semi-automated geomorphological mapping applied to landslide hazard analysisHansen, Andrew January 2007 (has links)
Computer-assisted three-dimensional (3D) mapping using stereo and multi-image (“softcopy”) photogrammetry is shown to enhance the visual interpretation of geomorphology in steep terrain with the direct benefit of greater locational accuracy than traditional manual mapping. This would benefit multi-parameter correlations between terrain attributes and landslide distribution in both direct and indirect forms of landslide hazard assessment. Case studies involve synthetic models of a landslide, and field studies of a rock slope and steep undeveloped hillsides with both recently formed and partly degraded, old landslide scars. Diagnostic 3D morphology was generated semi-automatically both using a terrain-following cursor under stereo-viewing and from high resolution digital elevation models created using area-based image correlation, further processed with curvature algorithms. Laboratory-based studies quantify limitations of area-based image correlation for measurement of 3D points on planar surfaces with varying camera orientations. The accuracy of point measurement is shown to be non-linear with limiting conditions created by both narrow and wide camera angles and moderate obliquity of the target plane. Analysis of the results with the planar surface highlighted problems with the controlling parameters of the area-based image correlation process when used for generating DEMs from images obtained with a low-cost digital camera. Although the specific cause of the phase-wrapped image artefacts identified was not found, the procedure would form a suitable method for testing image correlation software, as these artefacts may not be obvious in DEMs of non-planar surfaces. / Modelling of synthetic landslides shows that Fast Fourier Transforms are an efficient method for removing noise, as produced by errors in measurement of individual DEM points, enabling diagnostic morphological terrain elements to be extracted. Component landforms within landslides are complex entities and conversion of the automatically-defined morphology into geomorphology was only achieved with manual interpretation; however, this interpretation was facilitated by softcopy-driven stereo viewing of the morphological entities across the hillsides.In the final case study of a large landslide within a man-made slope, landslide displacements were measured using a photogrammetric model consisting of 79 images captured with a helicopter-borne, hand-held, small format digital camera. Displacement vectors and a thematic geomorphological map were superimposed over an animated, 3D photo-textured model to aid non-stereo visualisation and communication of results.
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