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Use of NoSQL technology for analysis of unstructured spatial data Texte intégral
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.
Afficher plus [+] Moins [-]Content marketing decisions for the customer value creation in social networks: ‘Ilzenberg manor’ case Texte intégral
2018
Repoviene, R., Vytautas Magnus Univ., Kaunas (Lithuania) | Pazeraite, A., Vytautas Magnus Univ., Kaunas (Lithuania)
This article presents theoretical and practical aspects of content marketing decisions for the customer value creation in social networks by using the case of the organic farm ʻIlzenberg manor’. Focus of this paper is to determine which content marketing decisions create the biggest value for the customer in social networks. The first part of the paper deals with theoretical insights into the content marketing decisions and their ability to create the customer value in social networks. Findings of theoretical analysis disclose that there are interfaces between content marketing, separate content marketing decisions and the customer value in the context of social networks. Respectively, it leads to an assumption that the usage of content marketing decisions can be valuable for the customer value creation in social networks. The second part of the paper focuses on the case analysis of the organic farm ‘Ilzenberg manor’. In order to determine which content marketing decisions create value for the customer in social networks, authors examine a correlation between separate content marketing decisions and consumer value indicators by using data from ʻIlzenberg manor’ Facebook page. The obtained results expose that not all content marketing decisions create value for the customer in social networks. Hence, it means that a selection of separate content marketing decisions in social networks can be made through the customer value perspective. The article ends with insights, conclusions, limitations and future research possibilities.
Afficher plus [+] Moins [-]Comparision of regeneration of Scots pine \{Pinus sylvestris L.\} in Myrtillosa and Hylocomiosa forest types after shelterwood cuttings Texte intégral
2020
Rums, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Straupe, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Zdors, L., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The aim of the study is to determine how successful the initial growth of naturally grown and planted pines is after performing the shelterwood cutting. The research includes tree count and height analysis in Myrtillosa and Hylocomiosa forest types with different regeneration methods in 2018. A total of 10 sites were arranged for the research, each site having 4 sample plots. All naturally regenerated and planted pine (2009, 2012 and 2013) heights were measured. Judging by the number of trees after shelterwood cutting, most sites should not be considered regenerated, additional planting or scarification of soil is required which can improve the efficiency of natural regeneration. In all the sites both in Myrtillosa and Hylocomiosa, after shelterwood cutting it was observed that the height of artificially regenerated trees is higher than the height of naturally regenerated trees, indicating the ability of planted pines to produce more rapid height increment in the first years of life, regardless of forest type. The basal area of the stand has a significant negative impact on the increment, and it indicates the need for the subsequent shelterwood cut to be performed. Although Hylocomiosa is a more fertile forest type than Myrtillosa, the height of the planted pine trees in Myrtillosa is higher than in Hylocomiosa, where, after shelterwood cutting, no sufficiently intensive agro-technical tending has been performed.
Afficher plus [+] Moins [-]Organosolv delignification of residual plantation willow bark after extractive removal Texte intégral
2020
Pals, M., Latvian State Inst. of Wood Chemistry, Riga (Latvia);University of Latvia, Riga (Latvia) | Lauberte, L., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Arshanitsa, A., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Vevere, L., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Jurkjane, V., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Telysheva, G., Latvian State Inst. of Wood Chemistry, Riga (Latvia)
Plantation willows are commonly grown plants which are widely used for energetic purposes that does not correspond completely to its potential. To fully integrate this resource into biorefinery scheme, it is necessary to study optimal conditions of willow bark processing, aimed for separation of bark components, their comprehensive characterization and profitable practical application. Extraction of secondary metabolites is well known approach for bark processing. But the separation of the main cell wall components including lignin from the residual biomass is less studied. In this work plantation residual willow bark after extractives separation by two different solvents (acetone and ethanolwater) was used as a feedstock for Organosolv delignification. Effect of temperature and catalyst used on the yield and properties of lignin isolated from residual bark by ethanol-water treatment was studied. It was possible to obtain pure lignin with high yields (up to 41%) that has the potential to be used for bio-plastic producing. Insoluble residue after delignification was carbohydrate rich (up to 80%) feedstock allowing its practical use for bioethanol producing.
Afficher plus [+] Moins [-]Smartphone-based colorimetric determination of DPPH free radical scavenging activity in vegetable oils Texte intégral
2020
Vucane, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Sabovics, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Leitans, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Free radicals can rapidly and irreversibly oxidize various structures, including unsaturated fatty acids in vegetable oils, which affect the sensory properties. Spectrophotometry is the most widely used method for the determination of free radical scavenging activity (RSA) using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Barrier to the further use of classical analytical methods to analyse biologically active compounds in foodstuffs is that equipment requires high cost and has limited mobility. One of solutions is to replace classical methods, such as spectroscopy, with smartphonebased colorimetry. Huawei P30 Lite smartphone was used for colorimetric detection. The free radical scavenging activity (RSA) in vegetable oil was detected using an application ‘Color Picker’, with image matching algorithm for red, green, and blue (RGB) model. RSA was expressed as percentage and measured by the DPPH method. The aim of the study was to determinate the total free radical scavenging activity with smartphone-based colorimetry. For the data comparison and accuracy spectrophotometer as analytical optical instrument was used. Eleven vegetable oils: sea buckthorn, sunflower, rice, macadamia nut, hemp, corn, grape, linseed, rapeseed, olive and milk thistle oils were selected for analysis. The best results with no significant differences (p is greater than 0.05) compared to smartphone-based colorimetry from spectrophotometry were determined using RG values. The poor results were detected by using B value (p is less than 0.05) and were not suitable for determination of RSA. Smartphone-based colorimetry can be used in the determination of the RSA in vegetable oils.
Afficher plus [+] Moins [-]Factors affecting smoked fish quality: a review Texte intégral
2020
Puke, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Galoburda, R,, Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Smoked sprats (Sprattus sprattus balticus) from the Baltic Sea are one of the most popular processed fish products in Latvia. The amount of catching and demand is annually increasing. For producers, it is important to provide stable quality throughout the year, which sometimes is challenging due to many factors. Smoked fish quality depends not only on the seasonality, but also on the applied technologies. The aim of the current study was to review research findings about factors affecting the smoked fish quality. The databases of Science Direct, Web of Science, Wiley Online Journals and Google Scholar were searched. The first parameter that affects quality of fish till processing is raw material, its catching place and season, as well as whether it is fresh or frozen fish, that includes not only microbiological parameters, but also physical and chemical changes in fish depending on the storage conditions. The second parameter is the applied pre-treatment methods (using salt, acids) before processing, which can improve fish texture and make better result for smoked fish. The third parameter is the used technology for the fish processing, heat treatment methods use of wood chips or liquid smoke, or adjustment of smoking conditions. These all together make a lot of sensorial and textural changes in the final product. If any of these parameters is changed during processing, they can affect the smoked fish quality. Therefore, to ensure constant quality of smoked fish, in-depth knowledge of parameters is extremely important.
Afficher plus [+] Moins [-]Cattle (Bos taurus) endometrium morphology on the seventh day of the estrous cycle Texte intégral
2020
Ponomarjova, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Sematovica, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Piginka-Vjaceslavova, I., Institute of Food Safety, Animal Health and Environment “BIORˮ, Riga (Latvia) | Vanaga, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aim of our study was to describe the histopathological and cytological characteristic of the cow endometrium on the seventh day of the oestrous cycle. In this study, 11 different breeds’ dairy cows (78.18 ± 37.46 months old, in 3.6 ± 2.17 lactation, the mean body condition score 3.4 ± 0.72 (5 points scale)) from Research and Study farm ‘Vecauce’ were selected. All cows were more than 210 days postpartum. Overall health and reproductive tract examination was performed, progesterone (P4) and estradiol (E2) concentration in blood serum were established and the biopsy and cytology samples of endometrium were taken. Mean E2 concentration was 14.92 ± 7.92 pg mLE−1, mean P4 concentration was 13.64 ± 9.44 nmol LE−1. The mean percentage in the cytology slides was established: epithelial cells 89 ± 9%, polimorphonuclear leukocytes (PMN) 6 ± 5%. Cytological subclinical endometritis (SE) was confirmed in 5 cows. Histopathological findings (out of 22 samples): endometrium stromal edema in 14, hemosiderin and hemosiderophages in 8, supranuclear vacuolization in 12, pseudodecidual reaction in 12 samples. No subnuclear vacuolization and mitosis in the glandular epithelium were detected. Histopathological examination did not reveal SE. Morphology between the uterine horns with and without corpus luteum (CL) and between cows with serum P4 level higher than 15 nmol LE−1 and lower than 15 nmol LE−1 were not statistically different (p is greater than 0.05). In conclusion, histopatological examination is more reliable diagnostic method for SE. Future investigation should be performed to establish cut-off values for the diagnosis of SE in cows more than 210 days postpartum.
Afficher plus [+] Moins [-]Legal and managerial solutions of public sector authorities for preserving ecosystem services of the lakes Texte intégral
2020
Marcinkeviciute, L., Vytautas Magnus Univ., Kaunas (Lithuania) | Vilkeviciute, J., Vytautas Magnus Univ., Kaunas (Lithuania) | Zukovskis, J., Vytautas Magnus Univ., Kaunas (Lithuania)
Although the problem of ecosystem diversity loss is of a global nature, the measures to solve it must be implemented at the national level. As a member of the European Union, Lithuania needs to have a clear position regarding the application of proposed socio-economic measures. The problems of lake ecosystem utilisation analysed in the article are based on the scientific knowledge which complies with the specifics of regional natural environment. The aim of the article is to systematize scientific knowledge about modern lake ecosystem services by explaining the fundamental adaptation patterns of ecosystems and their components. The article provides a complex assessment of the services provided by lake ecosystems, reveals management problems related to optimization of the use of lake ecosystems, presents recommendations on the improvement of legislation related to lake ecosystem services, regulations for protected areas, management plans, etc.
Afficher plus [+] Moins [-]Testing an operation of prototype for automated assessment: case of visitor profile of Gauja National Park Texte intégral
2020
Berzina, I., Vidzeme Univ. of Applied Sciences, Valmiera (Latvia) | Balodis, E., Vidzeme Univ. of Applied Sciences, Valmiera (Latvia)
This study is based on the authors’ research started in 2017 that resulted in the development of theoretical strategic and tactical models for the construction of a prototype for automated assessment of tourism economic impact in specific regions, including regions of national parks (NP), as well as for other studies. The aim of the research was testing the performance of the prototype in a research e-environment using the travellers’ survey data obtained in a study in 2019 on the national parks’ target groups (visitor behaviour) during the Gauja National Park (GNP) Travellers’ Days. The prototype was based on the open-source platform Drupal, MySQL used as a database management system (DMS). Drupal united with the Jupyter Notebook platform. The methodological substantiation of the test study is based on aspects of consumer behaviour. A quantitative study with details of qualitative research has been performed. Simple data sampling was used in the data acquisition, but in the analysis – induction, deduction approach, synthesis, data sorting and segmentation, determination of mean values and their expression in proportion; a comparative analysis was performed and conclusions characterizing the sample were made. After completing the prototype performance testing, the authors’ main findings indicate that the prototype’s performance efficiency in terms of time consumption is 23.3 times higher than equivalent work in MS Excel. The prototype has yielded quantitative results from the calculations, and that allows the formulation of the GNP’s Travellers’ Days visitor profile, which is characterized by a sample of the surveys.
Afficher plus [+] Moins [-]The change of natural landscape in Lithuania Texte intégral
2020
Ivaviciute, G., Vytautas Magnus Univ., Kaunas (Lithuania);Kaunas Forestry and Environmental Engineering Univ. of Applied Sciences (Lithuania);Klaipeda State Univ. of Applied Sciences (Lithuania)
The purpose of this article is to carry out an analysis of the natural landscape of the Republic of Lithuania in 2004–2019. During the preparation of the article, the following scientific methods were used: literature analysis, determination and evaluation of the current situation, grouping method, comparison method, graphical method, analytical and statistical analysis methods, logical analysis. The article analyses the change of the area of natural (natural, subnatural) landscape components (natural forests, wetlands, water bodies) during the period between the years 2004 and 2019. The analysis showed that the two components of the natural landscape of the Republic of Lithuania during 2004–2019 increased: the forest area (132,849.03 ha or 6.15%) and water bodies (3,668.49 ha or 1.38%). Unfortunately, the area of wetlands has decreased by 50,990.20 ha (35.05%). During the analysed period, the natural landscape of Lithuania increased by 85527.97 ha or 3.39%. At present, it is particularly important to care for and restore valuable landscape complexes to fulfil their ecosystem functions. One of the most important challenges is to reconcile urbanization and nature conservation so as not to reduce significant areas of the country’s natural landscape.
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