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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Řídicí systém laboratorního standu pro výukové účely / Control system of laboratory stand for educational purpose

Ondrejček, Vladimír January 2015 (has links)
This thesis proposes control circuit, that will be used in laboratory stand. The first part contains components that interact with the control circuit. The second part deals with the actual design of the control circuits, their design, appropriate selection of components and wiring. Third part deals with the assembly of the entire device and its commissioning.
102

Jämförelse av betesskador på sådda och planterade tallplantor - under en tvåårsperiod i södra Östergötland / Comparison of browsing damage to sown and planted pine plants - over a two-year period in southern Östergötland

Andersson, Jonatan January 2022 (has links)
Denna studie har jämfört betesskadorna i sådda och planterade tallbestånd över en tvåårsperiod. Totalt inventerades sex olika bestånd, varav tre sådda och tre planterade, enligt samma metod som ÄBIN. Resultatet visar en trend mot mindre andel skador i de sådda bestånden men endast en signifikant skillnad i år tvås mätningar för andelen gamla skador och andelen obetade stammar. Skadenivåerna för ÄFO 5 Kinda i Östergötlands län är också enligt ÄBIN betydligt högre än vad studiens resultat visar.
103

Ugdymo kirtimų projektavimas ir vertinimas / Planning and estimation of forest thinning

Banys, Tomas 09 June 2005 (has links)
The purpose of this study is to explore haw thinning planning standards agree with standards of estimation. Study was carried out in Kretinga forest enterprise Grūšlaukė forestry. Study of ratio of stands medial diameter and medial high was carried out in 11 – 60 years old pure spruce. The main purpose of thinning is to increase total productivity of forest stands and to form desirable structure and closeness of stands. It is important that all kinds of forest thinning concern biodiversity, increase resistance to wind and snow damage of forest stands, improve the quality of growing timber. Forests thinning use that timber part which rots in forests and gives no profit. To reach all these purpose forests thinning must be planned. Planning standard must be definite as it possible. It is important that these standards be suit with forests thinning normative. It was estimated that both standards has different rates and they are not matched. Thinning is planning by thickness of stands, but they are estimating by the number of trees in one hectare of stands. It was estimated that the ratio of forest stands medial diameter and medial high can be used in thinning planning. In pure spruce stands thinning must planned until ratio of medial diameter and medial high reach value: 0,8 in 11 – 20 years old stands; 0,9 in 21 – 40 years old stands; 1,0 in 41 – 60 years old stands.
104

Forest stand delineation through remote sensing and Object-Based Image Analysis

Ortega-García, José Antonio January 2018 (has links)
Forest stand delineation is an essential task of forest management planning which can be time consuming and exposed to subjectivity. The increasing availability of LiDAR data and multispectral imagery offers an opportunity to improve stand delineation by means of remotely-sensed data. Under these premises, ASTER imagery and low-density LiDAR data have been used to automatically delineate forest stands in several forests of Navarra (Spain) through Object-Based Image Analysis (OBIA). Canopy cover, mean height and the canopy model have been extracted from LiDAR data and, along with VNIR ASTER bands, introduced in OBIA for forest segmentation. The outcome of segmentation has been contrasted, on the one hand, assessing segments’ inner heterogeneity. On the other, OBIA’s segments and existing stand delineations have been compared with a new method of geometrical fitting which has been ad hoc designed for this study. Results suggest that low-density LiDAR and multispectral data, along with OBIA, are a powerful tool for stand delineation. Multispectral images have a limited predicting utility for species differentiation and, in practical terms, they help to discriminate between broad-leaved, conifer and mixed stands. The performance of ASTER data, though, could be improved with higher spatial resolution VNIR imagery, specifically sub-metric VNIR orthophotos. LiDAR data, in contrast, offers a great potential for forest structure depiction. This perspective is connected with the increasingly higher resolution datasets which are to be provided by public institutions and the rapid development of drone technology. Complexity of OBIA may limit the use of this technique for small consulting firms but it is an advisable instrument for companies and institutions involved in major forestry projects. / No
105

Avaliação da implantação de tecnologias de percepção de uso no ambiente residencial: uma proposta de metodologia. / Implementation evaluate of the use perception technologies in the residential environment: a proposed methodology.

Di Santo, Katia Gregio 04 July 2013 (has links)
O trabalho visa desenvolver uma metodologia para avaliar o impacto do emprego das tecnologias de percepção de uso no ambiente residencial quanto às reduções da demanda por energia elétrica e emissões de CO2. Tais tecnologias são: eliminador de stand-by, gerenciador de energia em computadores e sensor de presença. Inicialmente são selecionadas cargas residenciais e coletados seus dados para compor um banco de dados que será utilizado nas análises. Cada carga e conjunto destas recebe a tecnologia adequada, sendo então calculado o consumo evitado e o investimento relacionado. Foram criados perfis de funcionamento das cargas (6, 8 e 10h) para reproduzir diferentes comportamentos dos usuários e cenários de utilização das cargas (A, B e C) para a análise de sensibilidade. Foram feitos estudos de caso com diferentes modelos residenciais, sendo calculados: consumo e demanda de energia evitados e redução de emissões (considerando um conjunto de residências similares). Também foi realizada a análise de viabilidade econômica da implantação, considerando o Custo Marginal de Expansão do setor elétrico (visão do investidor em infraestrutura) e as tarifas de energia elétrica (visão do consumidor). Os resultados apontam para uma contribuição relevante, em termos de eficiência energética, do emprego de tais tecnologias, representando 35 a 85 MW evitados e redução de emissões de 59 a 145 mil tCO2/ano, dependendo do tipo de modelo residencial adotado, considerando a cidade de São Paulo. A análise de viabilidade econômica por payback simples apontou os seguintes retornos de investimento: 7,2 a 15,5 anos e 2,3 a 7,4 anos para o investidor em infraestrutura e consumidor, respectivamente, dependendo do modelo residencial. Já a análise por Custo da Energia Economizada (CEE) apontou a viabilidade para o consumidor em todos os modelos residenciais, exceto o de tarifa social. Desta forma, o emprego de tais tecnologias pode contribuir de forma importante com a postergação da expansão da matriz energética, resultando em redução de investimentos em expansão e das emissões de CO2 relacionados à geração de energia elétrica, além de poder representar economia na conta de energia dos moradores. / This study aims to develop a methodology to evaluate the utilization impact of the use perception technologies in residential environment in reducing the demand for electricity and CO2 emissions. These technologies are: standby killer, power manager for computers and presence sensor. Initially, residential loads are selected and their data is collected to compose a database that will be used in the analyzes. Each load and load group receives the appropriate technology and then are calculated the avoided consumption and the acquisition investment of the technology. Loads operational profiles (6, 8 and 10h) were created to represent user behaviors and loads usage scenarios (A, B and C) were created to conduct a sensitivity analysis. Case studies were carried out with different residential models, where were calculated: avoided electricity consumption and electric energy demand and CO2 emission reduction (considering a set of similar residences). Also, it was conducted the analysis of economic implantation viability, considering the Expansion Marginal Cost of the electric sector (infrastructure investor view) and the electric energy rates (customer view). The results point out to a relevant contribution, in terms of energy efficiency, of the utilization of such technologies, representing 35 to 85 MW of avoided demand and emission reductions of 59 to 145 thousand tCO2, per year, depending on the residential model type adopted, considering Sao Paulo city region. The analysis of economic implantation viability by payback point out the following investments returns: from 7.2 to 15.5 years and from 2.3 to 7.4 years to infrastructure investor and customer, respectively, depending on the residence model. The analysis by Cost of Saved Energy point out the implementation viability for the costumer in all residential models, except the social tariff. Thus, the use of such technologies can significantly contribute to the postponement of the energetic matrix expansion, resulting in reduction of expansion investments and of CO2 related to electric energy generation, besides can represent savings in the residents energy bill.
106

Influence de la mobilité de la colonne vertébrale sur les composantes posturale et focale du transfert assis-debout / Influence of the spine's mobility on the postural and focal components of sit-to-stand transfer

Alamini Rodrigues, Caroline 28 October 2016 (has links)
Il est connu que le mouvement volontaire entraîne une perturbation de la posture, qui nécessite d'être compensée par des mouvement contre-perturbateurs définis comme " ajustements posturaux ". Ce processus dynamique, qui se produit avant, pendant et après le mouvement focal, nécessite la mobilité de la chaîne posturale, avec un patron spécifique pour chaque tâche.L'objectif de cette thèse de doctorat a été d'explorer l'influence de la mobilité du rachis sur les composantes focale et posturale du transfert assis- debout, ou sit-to-stand (STS), qui est une tâche indispensable à l'autonomie fonctionnelle. Trois séries expérimentales ont évalué l'effet d'une restriction de mobilité de la colonne vertébrale sur les ajustements posturaux anticipateurs (APAs) et le mouvement focal de la tâche de STS réalisée à vitesse maximale. Des paramètres biomécaniques ont été calculés à partir des données fournies par un plateau de forces et un capteur de pression. La première série a évalué l'effet de la mobilité lombo-pelvienne au moyen de trois types de contentions lombaires, et a montré qu'une réduction du jeu articulaire de cette région était associée des APAs plus longs et plus amples, ainsi qu'à une augmentation de la durée du mouvement focal. La seconde série a mis en évidence les mêmes variations en explorant l'influence de la mobilité de la colonne cervicale au moyen de trois contentions cervicales. La dernière série s'est focalisée sur le rôle de l'augmentation de la tension musculaire le long du tronc, en utilisant un protocole spécifique de compression bimanuelle. Les résultats ont montré qu'une tension musculaire plus élevée induisait une augmentation de la durée des APAs mais sans variation de la durée du mouvement focal. L'ensemble de ces résultats suggèrent que la colonne cervicale et la colonne lombaire sont à la fois impliquées dans les composantes focale et posturale du STS, et que le maintien de leur mobilité peut favoriser l'autonomie fonctionnelle. En revanche, l'augmentation de la tension musculaire le long du tronc nécessite uniquement une réorganisation des ajustements posturaux pour maintenir le même niveau de performance. / It is well known that voluntary movements induce internal disturbances to posture, which need to be balanced by counter-pertubing movements defined as " postural adjustments ". This dynamic process, which occurs before, during, and after the focal movement, requires the mobility of the postural chain, with a specific pattern for each task. The aim of this PhD thesis was to explore the influence of spine mobility on the focal and postural components of the sit-to-stand (STS) task, which is instrumental for functional autonomy. Three series of experiments assessed the effect of spine mobility restriction on anticipatory postural adjustments (APAs) and focal movement (FM) of the STS task peformed at maximum velocity. Biomechanical parameters were calculated from force plate, and pressure sensor data. The first series assessed the effect of lumbo-pelvic mobility using three different lumbar contentions, and showed that restricted articular free play in this area was associated with longer and larger APAs, along with a higher duration of the focal movement. The second series of experiment showed the same variations when exploring the effect of cervical spine mobility using three different cervical contentions. The last series focused on the effect of increased muscular tension along the trunk, using a specific bimanual compressive load paradigm.The results showed that higher tension lead to longer APAs with no variation of FM duration. Taken together, these findings suggest that the lumbar and cervical spine are involved in both the focal and postural components of the STS task, and that preserving their articular free play might be useful to favour functionnal autonomy. In contrast, increased muscular tension along the trunk only require a reorganization of the APAs to keep the same level of task performance.
107

Avaliação da implantação de tecnologias de percepção de uso no ambiente residencial: uma proposta de metodologia. / Implementation evaluate of the use perception technologies in the residential environment: a proposed methodology.

Katia Gregio Di Santo 04 July 2013 (has links)
O trabalho visa desenvolver uma metodologia para avaliar o impacto do emprego das tecnologias de percepção de uso no ambiente residencial quanto às reduções da demanda por energia elétrica e emissões de CO2. Tais tecnologias são: eliminador de stand-by, gerenciador de energia em computadores e sensor de presença. Inicialmente são selecionadas cargas residenciais e coletados seus dados para compor um banco de dados que será utilizado nas análises. Cada carga e conjunto destas recebe a tecnologia adequada, sendo então calculado o consumo evitado e o investimento relacionado. Foram criados perfis de funcionamento das cargas (6, 8 e 10h) para reproduzir diferentes comportamentos dos usuários e cenários de utilização das cargas (A, B e C) para a análise de sensibilidade. Foram feitos estudos de caso com diferentes modelos residenciais, sendo calculados: consumo e demanda de energia evitados e redução de emissões (considerando um conjunto de residências similares). Também foi realizada a análise de viabilidade econômica da implantação, considerando o Custo Marginal de Expansão do setor elétrico (visão do investidor em infraestrutura) e as tarifas de energia elétrica (visão do consumidor). Os resultados apontam para uma contribuição relevante, em termos de eficiência energética, do emprego de tais tecnologias, representando 35 a 85 MW evitados e redução de emissões de 59 a 145 mil tCO2/ano, dependendo do tipo de modelo residencial adotado, considerando a cidade de São Paulo. A análise de viabilidade econômica por payback simples apontou os seguintes retornos de investimento: 7,2 a 15,5 anos e 2,3 a 7,4 anos para o investidor em infraestrutura e consumidor, respectivamente, dependendo do modelo residencial. Já a análise por Custo da Energia Economizada (CEE) apontou a viabilidade para o consumidor em todos os modelos residenciais, exceto o de tarifa social. Desta forma, o emprego de tais tecnologias pode contribuir de forma importante com a postergação da expansão da matriz energética, resultando em redução de investimentos em expansão e das emissões de CO2 relacionados à geração de energia elétrica, além de poder representar economia na conta de energia dos moradores. / This study aims to develop a methodology to evaluate the utilization impact of the use perception technologies in residential environment in reducing the demand for electricity and CO2 emissions. These technologies are: standby killer, power manager for computers and presence sensor. Initially, residential loads are selected and their data is collected to compose a database that will be used in the analyzes. Each load and load group receives the appropriate technology and then are calculated the avoided consumption and the acquisition investment of the technology. Loads operational profiles (6, 8 and 10h) were created to represent user behaviors and loads usage scenarios (A, B and C) were created to conduct a sensitivity analysis. Case studies were carried out with different residential models, where were calculated: avoided electricity consumption and electric energy demand and CO2 emission reduction (considering a set of similar residences). Also, it was conducted the analysis of economic implantation viability, considering the Expansion Marginal Cost of the electric sector (infrastructure investor view) and the electric energy rates (customer view). The results point out to a relevant contribution, in terms of energy efficiency, of the utilization of such technologies, representing 35 to 85 MW of avoided demand and emission reductions of 59 to 145 thousand tCO2, per year, depending on the residential model type adopted, considering Sao Paulo city region. The analysis of economic implantation viability by payback point out the following investments returns: from 7.2 to 15.5 years and from 2.3 to 7.4 years to infrastructure investor and customer, respectively, depending on the residence model. The analysis by Cost of Saved Energy point out the implementation viability for the costumer in all residential models, except the social tariff. Thus, the use of such technologies can significantly contribute to the postponement of the energetic matrix expansion, resulting in reduction of expansion investments and of CO2 related to electric energy generation, besides can represent savings in the residents energy bill.
108

Europäisches Fernsehwerberecht im Wandel der neuen Medien /

Klickermann, Paul Herbert, January 2001 (has links) (PDF)
Univ., Diss.--Mainz, 2001. / Literaturverz. S. 19 - 41.
109

En jämförelse mellan självföryngrade och planterade bestånd i Västernorrland : Finns det skillnader i andelen oskadade tallstammar?

Hiller, Sandra, Ågren, Samuel January 2023 (has links)
Tallungskogar utsätts ofta av skador från älg, detta är ett återkommande problem för många skogsägare. Syftet med denna studie var att undersöka om någon föryngringsmetod, plantering eller självföryngring uppvisade mindre andel skador av älg i tallungskog. Studien undersökte även om tallarnas höjd och om beståndet är röjt eller ej har påverkan på skademängden. Studien genomfördes genom en fältundersökning kring Gålsjöbruk i Västernorrlands län.Mellan dem inventerade variablerna kunde ingen signifikant reltion påvisas förutom ett p-värde mellan oröjd och röjd självföryngring, den låga datamöngden kan ha varit en bidragande del. Trender visade att stamantalet kan bidra till skillnader i mängden skadade tallar, där större mängd totalt antal stammar bidrar till mindre andel skadade tallar.Denna studie kan användas som stöd eller vägledning till när man bestämmer vilken föryngringsmetod man väljer för sitt framtida tallbestånd. Resultaten kan dock inte användas som facit utan mängden av utomstående faktorer bidrar till skademängden.
110

En jämförande studie mellan stickvägsgående och beståndsgående skördare och skotare.

Öberg, Daniel January 2016 (has links)
Thinning is performed today with essentially two thinning methods, with strip-roads or stand-thinning machines. The result after thinning affects the stands future development. In this study, the two thinning methods was compared with regard to distribution of basal area, resulting damage, the distribution of stems, actual thinning intensity and the impact that these differences may provide in the future. The survey was conducted in Sundsvall, Sweden in two different stands where basal area- surfaces, number of stems, damage and thinning strength was measured. The result shows that stand-thinning machines produce less damage to the stems and a more even distribution of the basal area. The strip-road method carried out a thinning of excessive thinning intensity of 50 % compared to 30 % for stand-thinning method. From a quality point of view the stand-thinning machines performed a better result. These machines have a lower production (harvested volume per hour) which probably results in lower financial gains in thinnings. Keywords: stand-thinning, basal area, thinning strength, Vimek, soil damage.

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