• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 7
  • 7
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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.
1

Påverkas geometriska krav på skogsbilvägar om ST-fordon införs? / Adapting forest road geometric to heavy timber vehicles.

Larsson, Adam January 2016 (has links)
The purpose of this thesis is to find out if it is possible to introduce a higher gross weight of trucks, from the current 64 tonnes to 74 tonnes. It would mean that the Swedish transportation would be more efficient and it would strengthen the Swedish business sector 's international competitiveness and also support the continued productivity, thus an efficient forest infrastructure is the key to obtain this. The report's input are from literatures, the Swedish Forest Agency’s recommended width increases of the road and simulations based on radius and angle of the curves. The results are based on calculations made ​​from the input data. The results of the report shows that the Forest Agency’s recommended width increases are enough to drive a 74 tonnes truck, which means that the 74 tonnes trucks are useable in the forestry after adjustments of the road. An increase from 64 tonnes to 74 tonnes would from an environmental point of view reduce carbon dioxide emissions by up to 11% and also the road would be better preserved when the axle load is distributed in a more efficient way.
2

Modeling and simulation of operational forest planning in relation to road network layout, cable corridor layout and timber transportation / 路網配置, 架線配置, 原木輸送に関連する森林作業計画のモデル化とシミュレーション

Shirasawa, Hiroaki 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第18321号 / 農博第2046号 / 新制||農||1021(附属図書館) / 学位論文||H26||N4828(農学部図書室) / 31179 / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 吉岡 崇仁, 教授 德地 直子, 准教授 長谷川 尚史 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
3

Comparação entre um modelo teórico e o real, no investimento em construção de estradas de uso florestal, relacionado com o volume de madeira transportado

Nascimento, Fernanda Regina [UNESP] 19 June 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-06-19Bitstream added on 2014-06-13T21:02:49Z : No. of bitstreams: 1 nascimento_fr_dr_botfca.pdf: 1004832 bytes, checksum: 083eba73355a538dc2c9db45f95e6000 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / A rede viária florestal influencia diretamente na qualidade do transporte. Ela serve de acesso às florestas, viabilizando o tráfego de mão de obra e o escoamento de matéria-prima. No entanto, uma das principais causas do aumento nos custos de construção é a má conservação e a falta de planejamento, visto que suas principais características são, muitas vezes, o baixo volume de tráfego e a utilização de veículos pesados e extrapesado. Além dos avanços tecnológicos e da importância do transporte para as empresas florestais, hoje, muitas empresas estão se preocupando com as condições ideais de rede viária florestal, principalmente no que se refere aos cuidados com planejamento e qualidade dos materiais utilizados. O objetivo deste trabalho foi propor e avaliar um modelo teórico de investimento para rede viária florestal em função do volume de madeira transportado. Verificou-se que os dados levantados em campo não eram compatíveis com o planejamento da empresa. A largura da pista de rolamento das estradas principais variou de 4 a 7 metros, sendo que pelo planejamento da empresa, elas deveriam ter 8 metros. Já para as estradas secundárias, a largura da pista de rolamento deveria ter 6 metros, no entanto, foi verificada uma variação de 4 a 7 metros. A análise comparativa dos custos, tendo como cenário primeiramente a situação das estradas levantadas in loco e os padrões de estrada indicados pelo modelo, permitiu notar que adoção do modelo teórico significaria acréscimo de R$ 521,30/km de estrada. Enquanto um segundo cenário comparativo composto pelas características de estradas levantadas em questionário, ou seja, as tidas como modelo para aberturas de novas estradas pela empresa, e os padrões de estrada indicados pelo modelo, indicou que o emprego do modelo teórico possibilitaria uma economia de R$ 2.036,00/km de estrada implantada... / The forest road net influences directly on transport Quality. It serves as access to forests, making possible the traffic of workers and the transporting of raw material. However, one of the main causes of the construction costs increase is the bad conservation and the lack of planning, since their main characteristics are, many times, low volume of traffic and the utilization of weighed and extra-weighed vehicles. Beside the technologic advances and the transport importance for forest companies, nowadays, many companies are worried with the ideal conditions of the forest road net, mainly on the concerning of planning and material quality. The objective of this work was to propose and evaluate a theoretical model of investment to forest road net in function of the volume of wood transported. It was verified that field data were not compatible with the company planning. The width of rolling track of main roads varied from 4 to 7 meters, although to company planning they should be 8 meters. For secondary roads, the width of rolling track should be 6 meters, although, it was observed a variation from 4 to 7 meters. Comparing theoretical model costs with real data, on the concerning of road width, it is verified that, in economic terms, the adoption of theoretical model would mean an investment of R$ 521,30/km more than in relation to that costs obtained from real data and comparing the costs of the theoretical model and the width data, obtained through consult formulary, showed that the usage of theoretical model would make possible an economy of R$ 2.036,00/km of built road. Costs of paved roads building were variable in function of rolling track width and the covering thickness, being this costs calculated as better as possible, as to allow an optimization on resources application.
4

Comparação entre um modelo teórico e o real, no investimento em construção de estradas de uso florestal, relacionado com o volume de madeira transportado /

Nascimento, Fernanda Regina, 1973- January 2005 (has links)
Resumo: A rede viária florestal influencia diretamente na qualidade do transporte. Ela serve de acesso às florestas, viabilizando o tráfego de mão de obra e o escoamento de matéria-prima. No entanto, uma das principais causas do aumento nos custos de construção é a má conservação e a falta de planejamento, visto que suas principais características são, muitas vezes, o baixo volume de tráfego e a utilização de veículos pesados e extrapesado. Além dos avanços tecnológicos e da importância do transporte para as empresas florestais, hoje, muitas empresas estão se preocupando com as condições ideais de rede viária florestal, principalmente no que se refere aos cuidados com planejamento e qualidade dos materiais utilizados. O objetivo deste trabalho foi propor e avaliar um modelo teórico de investimento para rede viária florestal em função do volume de madeira transportado. Verificou-se que os dados levantados em campo não eram compatíveis com o planejamento da empresa. A largura da pista de rolamento das estradas principais variou de 4 a 7 metros, sendo que pelo planejamento da empresa, elas deveriam ter 8 metros. Já para as estradas secundárias, a largura da pista de rolamento deveria ter 6 metros, no entanto, foi verificada uma variação de 4 a 7 metros. A análise comparativa dos custos, tendo como cenário primeiramente a situação das estradas levantadas in loco e os padrões de estrada indicados pelo modelo, permitiu notar que adoção do modelo teórico significaria acréscimo de R$ 521,30/km de estrada. Enquanto um segundo cenário comparativo composto pelas características de estradas levantadas em questionário, ou seja, as tidas como modelo para aberturas de novas estradas pela empresa, e os padrões de estrada indicados pelo modelo, indicou que o emprego do modelo teórico possibilitaria uma economia de R$ 2.036,00/km de estrada implantada...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The forest road net influences directly on transport Quality. It serves as access to forests, making possible the traffic of workers and the transporting of raw material. However, one of the main causes of the construction costs increase is the bad conservation and the lack of planning, since their main characteristics are, many times, low volume of traffic and the utilization of weighed and extra-weighed vehicles. Beside the technologic advances and the transport importance for forest companies, nowadays, many companies are worried with the ideal conditions of the forest road net, mainly on the concerning of planning and material quality. The objective of this work was to propose and evaluate a theoretical model of investment to forest road net in function of the volume of wood transported. It was verified that field data were not compatible with the company planning. The width of rolling track of main roads varied from 4 to 7 meters, although to company planning they should be 8 meters. For secondary roads, the width of rolling track should be 6 meters, although, it was observed a variation from 4 to 7 meters. Comparing theoretical model costs with real data, on the concerning of road width, it is verified that, in economic terms, the adoption of theoretical model would mean an investment of R$ 521,30/km more than in relation to that costs obtained from real data and comparing the costs of the theoretical model and the width data, obtained through consult formulary, showed that the usage of theoretical model would make possible an economy of R$ 2.036,00/km of built road. Costs of paved roads building were variable in function of rolling track width and the covering thickness, being this costs calculated as better as possible, as to allow an optimization on resources application. / Orientador: Paulo Torres Fenner / Coorientador: Alessandro Antonangelo / Banca: Elias Taylor Durgante Severo / Banca: Claudio Angeli Sansígolo / Banca: Jorge Roberto Malinovski / Banca: Nelson Yoshihiro Nakajima / Doutor
5

Sediment Delivery from Reopened Forest Roads at Stream Crossings in the Virginia Piedmont Physiographic Region, USA

Brown, Kristopher Ryan 03 June 2014 (has links)
Efforts to control surface runoff and erosion from forest roads at stream crossings are critical for the protection of aquatic ecosystems in forests. In this research, annual and event-based sediment delivery rates were estimated for reopened legacy roads at forest stream crossings in the Virginia Piedmont physiographic region, USA. Sediment delivery rates were compared among stream crossing approaches with diverse intensities of best management practice (BMP) implementations for surface cover and water control. Model predictions from the Water Erosion Prediction Project (WEPP) were compared to field observations of surface runoff and sediment delivery to evaluate model performance. Annual sediment delivery rates from reopened (bare) legacy road approaches to stream crossings were 7.5 times higher than those of completely graveled approaches. Sediment delivery rates ranged from 34 to 287 Mg ha⁻¹ year⁻¹ for the bare approaches and from 10 to 16 Mg ha⁻¹ year⁻¹ for the graveled approaches. Event-based surface runoff and associated total suspended solids (TSS) concentrations were compared among a succession of gravel surfacing treatments that represented increasing intensities of BMP implementations on reopened approaches. The three treatments were No Gravel (10-19% cover), Low Gravel (34-60% cover), and High Gravel (50-99% cover). Median TSS concentration of surface runoff for the No Gravel treatment (2.84 g L⁻¹) was greater than Low Gravel (1.10 g L⁻¹) and High Gravel (0.82 g L⁻¹) by factors of 2.6 and 3.5, respectively. WEPP predictions of event-based sediment yield show clear differences among the different road surface treatments, but prediction intervals were wide, reflecting substantial prediction uncertainty. These findings show that reopened legacy roads and associated stream crossing approaches can deliver significant quantities of sediment if roads are not adequately closed or maintained and that corrective best management practices (BMPs), such as gravel and appropriate spacing of water control structures, can reduce sediment delivery to streams. Watershed management decisions that hinge upon WEPP predictions of sediment yield from forest roads must necessarily take into account a wide range of potential erosion rates for specific management scenarios. / Ph. D.
6

森林施業の実態に基づいた森林基盤設備に関する研究

中澤, 昌彦, NAKAZAWA, Masahiko 12 1900 (has links)
農林水産研究情報センターで作成したPDFファイルを使用している。
7

Ceny stavebních objektů uplatňovaných v projektech krajinného inženýrství / Prices of constructions applied in landscape engineering projects

Kašová, Michaela January 2015 (has links)
Thesis theme is Prices buildings in the landscape engineering projects. The work is divided into two parts, theoretical and practical. The theoretical part explains the concepts that appear in the practical part. In the second part is illustrated in the example shown computation overhead, comparing several types of prices that were created using a decoupling of the program, and create cards budgetary indicators for the catalog cost indicators of common facilities landscaping.

Page generated in 0.0674 seconds