15 research outputs found
Evaluation of wood surface roughness depending on species characteristics
No full textThis study is focused on the impacts of species characteristics on the surface roughness of five species with different wood density namely white fir, Aleppo pine, European beech, walnut and white oak.
The sample specimens tested were 300x300x30 mm in size and their surface quality was evaluated by the "the direct contact method" based on a mechanical system of measurement, giving the possibility of reproducing the surface measured and analyzing its profile.
The surface roughness measurements were performed with a contact stylus profilometer, holding the moisture content of the specimens constant at 10%. The evaluation of the surface characteristics of the wood samples considered the roughness parameters: arithmetic mean deviation of the profile, maximum two point height of the profile, mean roughness depth and root-mean-square deviation of the profile.
From the study result showed different average values of surface roughness parameters for broadleaved and conifers species. The differences can be explain by the influence on the roughness of the wood surface of the wood texture and the texture uniformity
Evaluation of wood surface roughness depending on species characteristics
No full textThis study is focused on the impacts of species characteristics on the surface roughness of five species with different wood density namely white fir, Aleppo pine, European beech, walnut and white oak. The sample specimens tested were 300x300x30 mm in size and their surface quality was evaluated by the "the direct contact method" based on a mechanical system of measurement, giving the possibility of reproducing the surface measured and analyzing its profile. The surface roughness measurements were performed with a contact stylus profilometer, holding the moisture content of the specimens constant at 10%. The evaluation of the surface characteristics of the wood samples considered the roughness parameters: arithmetic mean deviation of the profile, maximum two point height of the profile, mean roughness depth and root-mean-square deviation of the profile. From the study result showed different average values of surface roughness parameters for broadleaved and conifers species. The differences can be explain by the influence on the roughness of the wood surface of the wood texture and the texture uniformity
Evaluation of wood surface roughness depending on species characteristics
No full textThis study is focused on the impacts of species characteristics on the surface roughness of five species with different wood density namely white fir, Aleppo pine, European beech, walnut and white oak.The sample specimens tested were 300x300x30 mm in size and their surface quality was evaluated by the “the direct contact method” based on a mechanical system of measurement, giving the possibility of reproducing the surface measured and analyzing its profile.The surface roughness measurements were performed with a contact stylus profilometer, holding the moisture content of the specimens constant at 10%. The evaluation of the surface characteristics of the wood samples considered the roughness parameters: arithmetic mean deviation of the profile, maximum two point height of the profile, mean roughness depth and root-mean-square deviation of the profile.From the study result showed different average values of surface roughness parameters for broadleaved and conifers species. The differences can be explain by the influence on the roughness of the wood surface of the wood texture and the texture uniformity
Flexible well pattern and NPV optimisation on large scale geothermal field development
No full textThe Netherlands has set the ambitious goal to be CO2 neutral by 2050 and signed the Paris Treaty in 2015. The contribution of geothermal energy to reaching this goal are outlined in the Masterplan in 2018 which attempts to reduce CO2 emissions. It is imperative to enhance geothermal participation in renewable energy resources, so this thesis proposes a consideration of large scale geothermal field development in order to meet these requirements. For these large scale projects, large scale geological heterogeneities must be taken into account in order to propose a development strategy that honours subsurface variability in properties like porosity or permeability of an aquifer. Furthermore, the nature of the large scale operations, inherently requires the consideration and application of well patterns typically used in oil and gas developments. Operating in these extensive domains, carries a lot of uncertainty in the final economical output of the project, so modelling the process could indicate the optimal conditions that would deliver the best possible operational outcome. Conceptual 2D model approaches were adopted to demonstrate the main ideas behind large-scale geothermal well pattern optimisation. The main objective of this project is to model, evaluate and optimise the performance of large scale geothermal field development. The proposed strategy is based on the use of well patterns as are frequently used in the oil industry. The heterogeneity in geological properties that may be expected to be encountered at larger spatial scales is addressed by the concept of a flexible well density function. This density function allows the well patterns to be resized (or ultimately, reshaped) and adapt to spatial variations in geological characteristics. The flexible well pattern is fed to an objective function created with embedded simulator. The output of the function is the net present value (NPV) of the project. Four test cases are created, starting with a homogeneous static model and building up more heterogeneous aquifer models, aiming to test the performance of the flexible well density function. The aquifer property models are representative of the West Netherlands Basin and specifically the Delft Sandstone Member. Per each aquifer model, line drive and 5-spot development strategies are assessed. Each development scenario is modeled in an objective function and optimised. The optimisation algorithm chosen is the Simplicial Homology Global Optimisation, suitable for black-box functions that show multiple local optimum solution and among them, a global optimum pattern size is found. The NPV of each project realisation is calculated based on the energy recovered and an economic model under Dutch fiscal conditions. The results suggest that, the flexible well placement is successfully aligning with the different aquifer geological properties. Pattern size is inversely correlated to porosity which corresponds to higher volume of pore fluid from which heat can be recovered. The optimisation algorithm managed to identify the global optimum solution of pattern size that delivers the highest possible positive NPV. The most efficient in terms of profitable strategy, is suggested to be the 5-spot pattern. The optimal pattern size ranges between 500 - 2160m depending on the aquifer model. The sweep efficiency, in terms of energy recovery, is also assessed per aquifer model and development strategy. The most efficient is the 5-spot pattern. The performance of the adopted optimisation algorithm, on the fully homogeneous aquifer, is tested with an exhaustive response curve of NPV. It is confirmed that the algorithm manages to identify the global optimum. The character of the NPV as a function of well pattern size/density proved the complexity of the system with respect to the amount and well types introduced. Different sensitivity analyses in the context of the uncertainty of the aquifer thickness, thermal conductivity, thermal heat capacity and full economic model are conducted in order to show the impact on the optimal patter size. The performance of the optimisation algorithm is assessed as well, indicating that further investigation on the tuning meta-parameters could potentially lead to better global optimum solutions in more heterogeneous aquifer models.Petroleum Engineering and Geo-science
Surface quality of planed tangential and radial sections of thermally modified Silver fir wood
No full textThe quality of glued or coated wood largely depends on the strength of the bond between the adhesive or coating and the wood surface. The roughness of the surface plays a crucial role, as it significantly impacts both the wettability and the effectiveness of the bond. This study was carried out to provide information on the surface roughness of Abies alba (silver fir) planed after thermal modification, focusing on the anisotropic behavior of the material, particularly along the radial and tangential sections. Four groups of eight samples without defects were prepared. Half of the samples of each group presented clear tangential section while the other half presented clear radial ones. One group was used as control and the others were heated, applying three different temperatures 160 °C, 190 °C and 220 °C, at atmospheric pressure for 3 hours. The control and the three other heat-treated groups of samples were processed along the grain by a planer machine. 10 m/min feed speed was applied. Surface roughness measurements were performed with a stylus profilometer. A positive correlation was observed between the modification temperature and the roughness of the surface. It was noted that the radial section of natural wood presented greater roughness than the tangential one. For temperatures lower than 200 °C the roughness of both sections resulted almost equal, while above this temperature the roughness of the radial section increased over 20 % compared to the roughness of the tangential one. The information provided by this study is very important for the gluing and finishing processes that can be applied to thermally modified wood.La calidad de la madera encolada o recubierta depende en gran medida de la fuerza de la unión entre el adhesivo o recubrimiento y la superficie de la madera. La rugosidad de la superficie juega un papel crucial, ya que afecta significativamente tanto a la humectabilidad como a la eficacia de la unión. Este estudio se llevó a cabo para proporcionar información sobre la rugosidad de la superficie de Abies alba (abeto plateado) cepillado después de la modificación térmica, centrándose en el comportamiento anisotrópico del material, particularmente a lo largo de las secciones radial y tangencial. Se prepararon cuatro grupos de ocho muestras sin defectos. La mitad de las muestras de cada grupo presentó una sección tangencial clara, mientras que la otra mitad presentó una sección radial clara. Un grupo se utilizó como control y los otros se calentaron, aplicando tres temperaturas diferentes 160 °C, 190 °C y 220 °C, a presión atmosférica durante 3 horas. El control y los otros tres grupos de muestras tratadas térmicamente se procesaron a lo largo de la fibra mediante una máquina cepilladora. Se aplicó una velocidad de alimentación de 10 m/min. Las mediciones de rugosidad de la superficie se realizaron con un perfilómetro de aguja. Se observó una correlación positiva entre la temperatura de modificación y la rugosidad de la superficie. Se observó que la sección radial de la madera natural presentó mayor rugosidad que la tangencial. Para temperaturas inferiores a 200 °C la rugosidad de ambas secciones resultó casi igual, mientras que por encima de esta temperatura la rugosidad de la sección radial aumentó más del 20 % en comparación con la rugosidad de la tangencial. La información proporcionada por este estudio es muy importante para los procesos de encolado y acabado que se pueden aplicar a la madera modificada térmicamente
Surface quality of planed tangential and radial sections of thermally modified Silver fir wood
No full textThe quality of glued or coated wood largely depends on the strength of the bond between the adhesive or coating and the wood surface. The roughness of the surface plays a crucial role, as it significantly impacts both the wettability and the effectiveness of the bond. This study was carried out to provide information on the surface roughness of Abies alba (silver fir) planed after thermal modification, focusing on the anisotropic behavior of the material, particularly along the radial and tangential sections. Four groups of eight samples without defects were prepared. Half of the samples of each group presented clear tangential section while the other half presented clear radial ones. One group was used as control and the others were heated, applying three different temperatures 160 °C, 190 °C and 220 °C, at atmospheric pressure for 3 hours. The control and the three other heat-treated groups of samples were processed along the grain by a planer machine. 10 m/min feed speed was applied. Surface roughness measurements were performed with a stylus profilometer. A positive correlation was observed between the modification temperature and the roughness of the surface. It was noted that the radial section of natural wood presented greater roughness than the tangential one. For temperatures lower than 200 °C the roughness of both sections resulted almost equal, while above this temperature the roughness of the radial section increased over 20 % compared to the roughness of the tangential one. The information provided by this study is very important for the gluing and finishing processes that can be applied to thermally modified wood
Ongoing Pristina – Belgrade Talks: from Decentralization to Regional Cooperation and Future Perspectives. EDAP 4/2012
No full textOn 17 February 2008, Kosovo declared independence, ending its nine years unresolved status. The principal goal was, and remains, the need to involve different communities in the state structures. The new state, which aims to fulfil all the obligations set by the Ahtisaari plan, is trying to complete the decentralization process the implementation of which continuous to face obstacles in the two main communities: the Serbs and the Albanians. This article discusses matters related to community acceptance of the decentralization process, the functioning of the parallel structures, the situation in North Kosovo and the on - going talks between Pristina and Belgrade. The article provides evidences that while the implementation of the decentralization process is the best possibility for Kosovo, it must not follow only an ethnic line
La lettura bilingue della poesia autotradotta : Un Caso Di Edizione Bilingue
No full textThis article starts from the hypothesis that the bilingual reading of self-translated poetry presents a new key of interpretation, different from both the monolingual and the bilingual reading of translation. The study is an investigation of this key, as it appears in the reading of the poetry of Gentiana Minga (b. 1971), an author of Albanian origin, active in Italy since the 90s. Through the reading of her latest collection of poems, a bilingual edition written in Italian and partly self-translated into Albanian, published by Terra d'ulivi edizioni in 2021, this study aims to demonstrate that the self-translated version in a bilingual edition is not read as a translation, but as part of one whole multilingual text.Quest’articolo parte dall’ipotesi che la lettura bilingue della poesia autotradotta offra una nuova chiave di lettura, diversa sia dalla lettura monolingue, sia da quella bilingue della traduzione. Lo studio è un’indagine di questa chiave, così come appare nella lettura della poesia di Gentiana Minga (n. 1971), autrice di origine albanese attiva in Italia dagli anni ‘90. Attraverso la lettura della sua ultima raccolta di poesie, un’edizione bilingue scritta in italiano e in parte autotradotta in albanese, pubblicata da Terra d’ulivi edizioni nel 2021, questo studio si propone di dimostrare che la versione autotradotta in un’edizione bilingue non viene letta come traduzione, ma come parte di un unico testo multilingue.English title in Web of Science: The Bilingual Reading of Self-Translated Poetry a Case of Bilingual Edition</p
La lettura bilingue della poesia autotradotta : Un Caso Di Edizione Bilingue
No full textThis article starts from the hypothesis that the bilingual reading of self-translated poetry presents a new key of interpretation, different from both the monolingual and the bilingual reading of translation. The study is an investigation of this key, as it appears in the reading of the poetry of Gentiana Minga (b. 1971), an author of Albanian origin, active in Italy since the 90s. Through the reading of her latest collection of poems, a bilingual edition written in Italian and partly self-translated into Albanian, published by Terra d'ulivi edizioni in 2021, this study aims to demonstrate that the self-translated version in a bilingual edition is not read as a translation, but as part of one whole multilingual text.Quest’articolo parte dall’ipotesi che la lettura bilingue della poesia autotradotta offra una nuova chiave di lettura, diversa sia dalla lettura monolingue, sia da quella bilingue della traduzione. Lo studio è un’indagine di questa chiave, così come appare nella lettura della poesia di Gentiana Minga (n. 1971), autrice di origine albanese attiva in Italia dagli anni ‘90. Attraverso la lettura della sua ultima raccolta di poesie, un’edizione bilingue scritta in italiano e in parte autotradotta in albanese, pubblicata da Terra d’ulivi edizioni nel 2021, questo studio si propone di dimostrare che la versione autotradotta in un’edizione bilingue non viene letta come traduzione, ma come parte di un unico testo multilingue.English title in Web of Science: The Bilingual Reading of Self-Translated Poetry a Case of Bilingual Edition</p
