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Use of NoSQL technology for analysis of unstructured spatial data
2018
Polakova, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Vitols, G., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Every day millions of new data records with spatial component are produced in the world, which provide valuable information to make decisions and solve business-related issues. However, a large part of this data is hardly analysed because of their different structures and schemas. The aim of the paper is to improve the integration, processing and analysis of unstructured spatial data. During the research, the author analysed geospatial data types and sources, explored NoSQL solutions for geospatial data processing and chose the open-source tools which are the most appropriate for the stated goals, as well as analysed the coverage of forest areas with protected zones using MongoDB database capabilities and visualized results in a map, using QGIS software. MongoDB is a useful tool for geospatial data analysis and has a large number of embedded topology analysis functions and has drivers for widespread programming languages like JavaScript, Python, PHP, Java, Scala, CNo., C, C + +, etc. QGIS has extensions that allow to make connections to databases, including a connection with MongoDB. Using these features, the developers can develop geographic information systems to analyse geospatial data – structured, semi-structured and unstructured. Generally MongoDB is used for real-time data analysis; however, complicated analysis of large data sets can take up to hours and even days, so it is still necessary to find the best solution to get results in an acceptable time for users. Using MongoDB together with Apache Hadoop – the framework to support big data applications – could be a possible solution for this problem.
Show more [+] Less [-]Translation of experience and knowledge in private forest owners’ networks
2018
Felcis, R., University of Latvia, Riga (Latvia)
Fragmentation of private property (142 thousand private forest owners) cause the challenge for governing forests, because forests are part of wider forest ecosystems, but at the same time narrowly assigned by private borders. Land restitution put the new pressures on path dependent management and new possibilities and responsibilities (that were emergent features of private forest governance). This article is part of doctoral thesis about the common governance of private forests with particular aim to focus on describing knowledge and experience exchange in private forest owners’ networks in this paper. The research question for this article is to help to find out how the translation of experience and knowledge manifest itself in private forest owners’ networks? The best theoretical model to fit this situation is the concept of translation from actor-network theory and emergent norm theory. Case study approach was selected to follow actors in forest owners’ networks. The cases are forest owners’ cooperatives, forest owners NGO’s, as well as other forms, in particular, forest extension services and cases where an emergent process can be seen. The empirical material shows that translation of experience and knowledge manifest itself in few important ways, namely, at first, in a negotiation of needs and agreement on private forest owners’ needs; secondly, in stewardship role of multi-functional actors; thirdly, in emerging and evolving legislative norms. A multi-functional actor is a term offered in order to reveal a wide range of mediation forms in multicultural multi nature of forests as governed property and forests as integral part of ecosystems.
Show more [+] Less [-]Parameters for areas of pre-commercial thinnings conducted in private forests during 2007–2017
2018
Bermanis, R., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Straupe, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Zvirbule, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The paper covers analysis of pre-commercial thinning performed in private forests over the period of 2007–2017. Since 2007, permanent and considerable European Union subsidies for pre-commercial thinning have been available; resulting in a significant increase in area of thinned young stands in private forests. The aim of this research is ascertain pre-commercial thinning activity depending on the type of forest owner (individuals, legal persons or local municipality), forest stand type (forest stand or plantation) and origin (natural or artificial) as well as the forest owner’s intention to apply for European Union subsidies. Data analysed were obtained from Forest State Register – national data base, managed by state authority State Forest Service and continued analysis comprise two main topics – ascertain amount and type of young stands owned by different type of private forest owners and amount and type of conducted pre-commercial thinning. In comparison with other type of forest owners, legal persons have significantly higher amount (47%) of young plantation forest and forest stands from the total forest stands area. The highest intensity of thinning was conducted in plantation forests of artificial origin owned by legal and physical persons, also forest stands with artificial origin owned by physical persons. The current period for European Union Rural development programme will be over in 2020; therefore, it is important to analyse the existing approach of granting subsidies to forestry and find the improvement necessary for the planning period from the year 2021.
Show more [+] Less [-]Effect of thermal treatment on physical and mechanical properties of birch and pine wood
2018
Antons, A., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Cirule, D., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Verovkins, A., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Kuka, E., Latvian State Inst. of Wood Chemistry, Riga (Latvia);Riga Technical Univ. (Latvia)
No simple method has yet been found for satisfactory wood bio-resistance improvement regarding material performance in its end-use. An attempt to obtain material with proper strength and bio-durability by combined wood thermal modification and impregnation with a biocide is being researched. To select the most appropriate treatment conditions for the combined process, changes in wood physical and mechanical properties depending on the treatment temperature were investigated in the present study. For the investigation, in Latvia the most widespread wood – softwood pine (Pinus sylvestris L.) and hardwood birch (Betula spp.) was used. Changes of wood mechanical and physical properties due to thermal modification were investigated and effect of treatment temperature and relative humidity on wood characteristics evaluated. It was found that, due to different degree of changes, no identical treatment conditions suit for birch and pine wood. Birch wood is considerably more sensitive to temperature and acceptable strength was maintained only for birch wood treated at 150 °C and for pine wood treated at 160 °C. Nevertheless at higher environmental humidity equilibrium moisture content and consequently radial and tangential swelling increased for all studied wood types, substantially smaller changes due to elevated humidity were detected for modified wood.
Show more [+] Less [-]Restriction of liquid water spreading in overlaid plywood top veneer
2018
Cirule, D., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Kuka, E., Latvian State Inst. of Wood Chemistry, Riga (Latvia);Riga Technical Univ. (Latvia) | Verovkins, A., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Andersone, I., Latvian State Inst. of Wood Chemistry, Riga (Latvia)
Plywood overlaid with resin impregnated paper films is used in various decorative applications for which high stability of aesthetic qualities is of great importance. The top veneer of the plywood for these materials is perfectly protected from a direct contact with water as far as the covering film is not damaged. However, in case of film damage water can cause clearly visible defects in a relatively short period of time. To reduce these types of defects, unsophisticated and efficient way was developed. It involves filling the vessel system of the top veneer with industrial phenol-formaldehyde resin by using a hot-press. Influence of some phenol-formaldehyde resin properties on its penetration in birch veneer as well as the effect of wood moisture content were tested. The proposed top veneer pre-treatment method with phenol-formaldehyde resin reduced the average swelling zone distance from damage site by half for oven pre-dried plywood with 3% moisture content before treatment. Moreover, it was found that using plywood with moisture content of 9% the swelling zone distance was reduced by two thirds compared to untreated overlaid plywood.
Show more [+] Less [-]Density of wood of pine and spruce in the postagrogenic soil of the boreal zone
2018
Janusz, S., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation) | Danilov, D., Leningrad Scientific Research Inst. of Agriculture ''Belogorka'', Belogorka village, Gatchina district, Leningrad region (Russian Federation)
The aim of this research was to study the effect of the stand composition on the density of pine and spruce wood growing on former arable lands. Sample areas are located in mixed mature pine- and spruce-prevailing stands in Leningrad region, Russia. For the reliable determination of the basic density of spruce and pine wood, selection of model trees was carried out and cores were taken. Based on the data obtained from stems of 36 model trees from 3 sample plots, conversion equations were calculated to determine the basic density of wood. The measurements of the spruce and pine wood density were processed using variational statistics. The results have shown that the pine forms a more homogeneous wood than the spruce. On former arable lands, spruce has a denser wood than pine under the same growth conditions. The stand composition has a significant effect on the density of spruce rather than pine.
Show more [+] Less [-]Organoclay additive for plywood protection against brown and white rot fungi
2018
Zommere, Z., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Irbe, I., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Grinins, J., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Rudzite, S., Latvijas Finieris, AS, Riga (Latvia) | Nikolajeva, V., University of Latvia, Riga (Latvia)
In this study, antifungal properties of an organoclay additive were investigated. Two types of organoclay (red and white) were tested in Petri dishes to determine their toxicity against the brown rot fungus Coniophora puteana and the white rot fungus Trametes versicolor. Red organoclay was more efficient than the white one and, depending on the fungus, inhibited or stopped the fungal growth. Red organoclay was chosen as an additive to produce a new type of plywood product. Biological durability of this plywood product was determined according to the methods: NF B 51-295 (bending strength test) and LVS ENV 12038:2002 (mass loss test). The loss in bending strength exceeded 81% and 65% after exposure to brown and white rot fungi, respectively. The mass loss of the plywood product after the decay test was higher than 3%, which defined the material as not fully resistant against decay fungi. According to CEN/TS 15083-1:2005, the plywood product corresponded to the durability class 3 (moderately durable) to 5 (not durable) depending on the fungus.
Show more [+] Less [-]Birch plywood sample tension and bending property investigation and validation in SolidWorks environment
2018
Zalcmanis, A., Latvijas Finieris, AS, Riga (Latvia) | Zudrags, K., Latvijas Finieris, AS, Riga (Latvia) | Japins, G., Riga Technical Univ. (Latvia)
Birch plywood has proved itself to be one of the most rational ways of wood processing. Growing demand of high performance birch plywood products requires a complex numerical analysis based on Finite Element Method (FEM), instead of using simple analytical assumptions, which prevent optimization of plywood construction (lay-up). In the research samples of birch plywood of several thicknesses, both sanded and non-sanded, with fibre direction of external veneer both in the longitudinal and transverse directions were tested. An extensometer and optical strain gauge were used for strain measurement. The FEM analysis, using commercial software SolidWorks Simulation Premium (SW), versus experimental bending and tension testing according to LVS EN 789 was carried out in this paper. The analysis of results indicates that there is a high correlation between the results of the experiments and the FEM. Particularly for in tension loaded specimens one can be tested up to the maximum ply strength (100 MPa); meanwhile, in bending up to 71MPa – the average stress in load bearing ply at the proportionality limit. Due to software restrictions, shear stresses cannot be evaluated. Future studies are considered to investigate terms for designing plywood with dynamic properties of strength and stiffness to be taken into account.
Show more [+] Less [-]Road landscape modelling
2018
Vugule, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Mengots, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Stokmane, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Road landscapes can be considered important resources for place development. They create impression about the infrastructure of places and transport, which is an important aspect of attracting investment and tourism development. Yet this field of landscape planning and design is hardly studied and needs more attention in Latvia. Institutions at different planning levels and from several fields of expertise are involved in road landscape development. In order to achieve successful cooperation among all the parties involved, it is necessary to reflect the information about road landscape development in the way that it can be easily perceived and understood. Studies in landscape perception prove that people perceive visual information about landscape design and planning better than textual information and regular maps. The purpose of the paper is to introduce with a method of three dimensional (3D) road landscape modelling, developed by authors as a tool for road landscape design aesthetic evaluation, which can be used to demonstrate design variants to wider public and stakeholders. We demonstrate what kind of data are necessary for road landscape modelling, how they are obtained and processed, why certain modelling programs are chosen. The methodology, problems, which occurred during the modelling, and the chosen solutions are described. Results show that chosen methodology is appropriate for large scale projects. The experience gained from the project helps to evaluate the suitability of certain computer programs for road landscape planning and design.
Show more [+] Less [-]Changes of the forest land area and spatial structure in urban landscapes of Lithuania
2018
Tiskute-Memgaudiene, D., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The territorial planning and the management of urban surfaces force the decrease of green spaces in urban landscapes. As the urbanization process during past decades of the last century was quite intensive not only in Europe but also in Lithuania, findings describing changes of forest cover as well as spatial structure of the forest land are requested. The aim of this study was as follows: first, to calculate and compare areas of the forest land in six major cities of Lithuania in 1950 and 2011, second, to evaluate the spatial structure of the forest land by investigated cities within the period of 1950 – 2011. Methods of descriptive statistical analysis and spatial analysis using ArcGIS and MS EXCEL software were used. The study was based on two geodatabases, representing the forest cover in 1950 and 2011. Results of this study revealed that areas of the forest land increased in all investigated cities excluding Panevėžys city. The increases of areas of the forest land were discovered to vary from 0.8% to 9.5%. The largest increase was found in Vilnius city (9.5%), the smallest – in Šiauliai city (0.8%). The decrease by 0.9% of the forest land was found just in Panevėžys city. No significant changes of the forest land spatial structure were found in largest cities of Lithuania, i.e. Vilnius city and Kaunas city. The spatial structure of forest land in other investigated cities tended to degrade.
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