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Oil spills detection by means of infrared images and water quality data using machine learning Полный текст
2023
Zavtkevics, Vladislavs | Gorelikovs, Dmitrijs
The paper presents the results of the research on oil spill detection using machine learning methods such as Support Vector Machine (SVM) for classification of infrared images and Logistic regression for water quality parameters. This paper focuses on real time detection of oil spills using infrared images and water quality data obtained by RPA equipped with multi-sensor payload. The developed Naïve Bayes (NB), SVM and Logistic regression classification models for prediction of oil spill have been successfully tested in real experiment conditions. All developed classification models were tuned using grid search method and main tuning parameters to determine the optimal parameters. The proposed complex algorithm for identification of oil spills using infrared images and water quality parameters is evaluated by experiments in real environment conditions. The proposed algorithm is based on the binary SVM and NB classification of infrared images and the classification of water quality parameters using the machine learning method logistic regression allows to rapidly and with high accuracy identify any oil pollution of water. Proposed complex algorithm achieves higher accuracy and efficiency; moreover, the developed machine learning models will further reduce the probability of human error and save man-hours of work.
Показать больше [+] Меньше [-]Water stable isotopes as drinking water quality indicator in dug wells of Eastern Latvia Полный текст
2023
Purmalis, Oskars | Babre, Alise | Klavins, Linards | Ozola-Davidane, Ruta | Popovs, Konrads | Grinfelde, Inga
Stable isotope ratios of water (δ2H and δ18O) are important indicators which describe hydrological processes in the environment. These parameters allow to analyse structure, status, migration of pollutants and processes of the groundwater system. Groundwater from dug wells is widely used as a drinking water source highlighting the importance of investigation of water quality and its possible flows and sources. Despite available centralized water systems, there are still wide territories where dug wells are the main source of drinking water supply. Dug wells are recharged from shallow groundwaters which makes them more vulnerable to anthropogenic contamination. Therefore, quality monitoring and estimation of anthropogenic influences are of importance. Quality requirements of drinking water do not provide measurements of stable isotope ratios in drinking water, but the combination of those elements can be valuable for the characterization of impacts on groundwater quality. The aim of this study was to survey 64 dug wells in Eastern Latvia and analyse water quality together with measurements of stable isotope ratios. Measurements were performed twice, i.e., autumn and spring to track water sources in wells and describe the extent of possible impacts. This approach can indicate the magnitude of local factor impacts on drinking water quality. Surveyed wells provide high differences in analysed parameters, for example, nitrate concentrations in autumn varies from 0.44 to 108.26 mg LE−1. Also, other detected parameters are variable; therefore, tracking water flow with stable isotope values gives better insight into the water quality of the studied region.
Показать больше [+] Меньше [-]Improving intrusion detection intelligence by open data usage Полный текст
2023
Paulins, Nauris
Cyberattacks have become a regular part of network activity. To mitigate the risks from possible threats, organisations have implemented firewalls and intrusion detection systems, which can help stop network attacks. The problem is that often the accuracy of these systems is not effective enough. Another part of network security is security information and management platforms. These systems are more advanced versions of Threat Intelligence Platforms, because it is possible to make in-depth analyses of real-time events in a network. This research paper proposes improving intrusion detection system functionality using Open-Source Intelligence. Anomaly-based intrusion detection systems often generate alerts, but these alerts require deeper analysis to understand whether it is a real attack or just a false alarm. By making Open-Source Intelligence requests and evaluating extra information, it is possible to make more precise rules to stop attacks against network infrastructure. Open-Source Intelligence requests are generated directly from the intrusion detection system or with Python scripts based on the organisation’s infrastructure profile. The proposed architecture was experimentally tested by automating Open-Source Intelligence requests and intrusion detection rule generation by Python scripts.
Показать больше [+] Меньше [-]Factors influencing student initiative in effective mathematics studies at universities Полный текст
2023
Sergejeva, Natalija | Zeidmane, Anda
One of the most important problems of modern education is low achievement in STEM (Science, Technology, Engineering and Mathematics) subjects. Poor performance in mathematics is a serious problem in many countries. In order to improve the effectiveness of mathematics studies, it is more important to improve such key factors as students’ learning self–efficacy and learning initiative. This study is devoted to students’ learning initiative and the factors influencing it. It is the insufficiency of students’ regular learning initiative in the study process that is the basis of the fact that students are not sufficiently prepared for the final exam. Based on the research results of the scientific literature, a questionnaire was created that investigated the students’ learning initiative and factors that could improve it – attitude towards mathematics studies, motivation, as well as emotional factors that are often related to Causal attributions. The research was conducted at Latvia University of Life Sciences and Technologies, surveying students of various specialties and various courses. Fisher’s exact test of independence is used to determine whether there is a significant relationship between two categorical variables – the respective factors and performance on the math completion test. The results show that one of the main causes is a low self–assessment of mathematics competence, which in turn affects motivation and attitude towards mathematics studies and slows down learning initiative.
Показать больше [+] Меньше [-]Digitization of higher education in Ukraine: Organizational and applied aspects Полный текст
2023
Zamkova, Iryna | Dubinina, Maryna | Syrtseva, Svitlana | Cheban, Yuliia | Luhova, Olha | Kuchmiiova, Tetiana
Today in Ukraine, a digital transformation of the educational system of higher education is taking place at a rapid pace, in which information and communication technologies are not becoming an additional ʻload’ in learning, but an integral part of a comprehensive educational process, which increases its efficiency. At the same time, there are a number of challenges, including such specific ones as unprovoked military aggression, which complicates the process of entry of higher education in Ukraine into the global educational digital environment. To assess the significance of the digitalization of the educational system of higher education in Ukraine in specific conditions, to analyse the attitude of the teaching staff and students to online education, to establish technical means of participation in the educational process, to determine the advantages and disadvantages of distance learning through the prism of the experience of teaching staff and students, we used three main methods: the survey method, the method of analysis and synthesis, the graphical method. As a result of the study, the authors revealed the general concept of digitalization and its educational dimension; identified the main challenges faced by higher education institutions in the digital environment; determined the impact and scale of military aggression by the Russian Federation on the activities of Ukrainian universities; established the features of training in the digital environment by institutions of the higher education of Ukraine.
Показать больше [+] Меньше [-]Comparative study on the impact of COVID-19 on emotional well-being in the workplace Полный текст
2023
Vintere, Anna | Bartusevičienė, Inga | Aruvee, Eve | Rimkuviene, Daiva
Individuals’ emotional well-being is determined by several factors, including the ability to cope with daily stress and the ability to cope with various daily challenges. Ability of the management to provide favourable psychoemotional and psychosocial conditions within their team is particularly important. However, managers do not always have the knowledge and skills to lead their teams. For the development of the methodology, a study of the scientific literature on topical issue like healthy workplace was performed. The empirical part of the study is based on the results of the survey conducted Lithuania, Latvia, Estonia and Sweden within the Nordplus project ‘Dealing with anxiety during a pandemic to enhance adult well-being’ on the impact of COVID-19, as well as the training that would be necessary for the managers of companies or organizations to promote emotional wellbeing in the workplace. The comparative study was conducted from the perspective of both employees and managers. The results show that the impact of the COVID-19 pandemic on workplace and the well-being of employees was not strong for the respondents, depending mainly on the job position, the size of the organization and country. Managers and employees consider various psychological trainings essential.
Показать больше [+] Меньше [-]Weather sensitivity of radial increment of Pinus strobus in an experimental plantation in the western part of Latvia Полный текст
2023
Jansone, Diāna | Matisons, Roberts | Straupe, Inga | Jansons, Āris
The phenomenon of global climate change holds utmost importance in its impact on forest ecosystems. To mitigate the effects of this phenomenon, several European countries have introduced non-native tree species into their forests. However, comprehensive ecological analysis is needed to assess the suitability of these non-native species. Pinus strobus is often considered a potential substitute for native species. Tree-ring analysis is a useful methodology for evaluating the relationship between tree growth and meteorological conditions, given the significant impact of these conditions on tree development. In this study, 25 core samples were collected from an experimental plantation of Pinus strobus located in the western part of Latvia for analysis. The plasticity of the tree-ring width of Pinus strobus was evaluated using a multiple additive regression model. The analysis revealed that the previous summer precipitation was a significant factor, indicating the drought sensitivity of the increment. Additionally, the temperature in the previous July and August was also found to be a significant meteorological parameter, suggesting some tradeoffs between growth and the formation of nutrient reserves. The estimated growth responses suggest that the radial increment of Pinus strobus growing outside its native range is highly weather-sensitive, implying uncertainty in its growth with anticipated climatic changes. These findings emphasize the need for further ecological analysis to determine the suitability of non-native tree species and their ability to withstand the climatic changes.
Показать больше [+] Меньше [-]A review: Using legumes to develop products for patients with psychiatric disorders Полный текст
2023
Plocina, Lasma | Beitane, Ilze
Mortality rates and co-morbidities are high in people with psychiatric disorders. These patients have unhealthy dietary habits, which include increased consumption of fast food, snacks, sweets, saturated fats, and reduced consumption of protein, fruits, vegetables, and legumes, which contributes to the risk of developing chronic diseases such as obesity, type 2 diabetes, and cardiovascular disease. Unhealthy and monotonous eating habits lead to a significant lack of nutrients such as protein, omega-3 fatty acids, B-group vitamins, and fibre. The aim of the literature review is to investigate the main diet problems of patients with psychiatric disorders and, based on the studies on the nutritional value of legumes, to evaluate their suitability for the development of new products for patients with psychiatric disorders. Studies show the beneficial effects of legumes on the regulation of rapid fluctuations in cholesterol, blood pressure, excess body weight, and glucose levels, which in general delay the formation of inflammation and reduce the risk of psychiatric disorders. The benefits of legumes are due to their high protein and fibre content, low fat content, and content of iron, copper, magnesium, zinc, and B-group vitamins. In addition, legumes contain bioactive compounds that contribute to the prevention of chronic diseases.
Показать больше [+] Меньше [-]Determining optimal conditions for growing recombinant vectors to be used in developing a bovine tuberculosis vaccine Полный текст
2023
Nurpeisova, Ainur | Abay, Zhandos | Shorayeva, Kamshat | Sadikaliyeva, Sandugash | Yespembetov, Bolat
Two recombinant influenza A virus vectors expressing the ESAT 6 and TB10.4 mycobacterial proteins from the non-structural (NS) gene were constructed via reverse genetics technique to develop a specific means of prophylaxis for bovine tuberculosis. We experimented to determine optimal conditions for growing recombinant vectors in Vero cell culture and chick embryos. This study established that the maximum amount of virus builds up in a Vero cell culture with the Dulbecco’s Modified Eagle’s Medium (DMEM) serum-free medium. However, using cell culture to produce vector vaccines is labour-intensive and inefficient. An alternative way, a traditional, time-tested technique, is provided by growing samples in chick embryos. One of the advantages of this technique is its affordability and availability, enabling easy scale-up of vaccine production. In the optimization experiments, the FLU-ΔNS_ESAT 6 and FLU-ΔNS_ТВ10.4 viruses constructed were inoculated into 10-day-old chick embryos. It was determined that the optimal incubation temperature that led to the highest virus build-up was 37 ± 0.5 °С. And the infectious activity level of the FLU-ΔNS_ESAT 6 recombinant vector was at 8.95 ± 0.07 log10EID50 0.2 cmE−3, while that of the FLU-ΔNS_ТВ10.4 was at 9.20 ± 0.07 log10EID50 0.2 cmE−3, what was provided by infectious doses of 1000–10000 EID50 , which makes it possible to create a virus-containing material with a hemagglutination activity level of 1:64. The size of recombinant vector amplicons expressing proteins ТВ10.4 and ESAT 6 was 1170 bp and 1175 bp, respectively. Electron microscopy images confirm that the developed virions are morphologically similar to the avian influenza virus.
Показать больше [+] Меньше [-]Hyperspectral imaging for early detection of foliar fungal diseases on small grain cereals: A minireview Полный текст
2023
Fiļipovics, Maksims
Globally crop pathogens and pests cause significant yield and quality losses in agriculture production systems. Foliar fungal diseases of small grain cereals are economically among the most important diseases worldwide and in the Baltics. Finding an effective, reliable, and easily accessible method for plant disease diagnosis still presents a challenge. Currently used methods include visual examination of the affected plant, morphological characterization of isolated pathogens and different molecular, and serological methods. All of these methods have important limitations, especially for large-area applications. Hyperspectral imaging is a promising technique to assess fungal diseases of plants, as it is a non-invasive, indirect detection method, where the plant’s responses to the biotic stress are identified as an indicator of the disease. Hyperspectral measurements can reveal a relationship between the spectral reflectance properties of plants and their structural characteristics, pigment concentrations, water level, etc., which are considerably influenced by biotic plant stress. Despite the high accuracy of the information obtained from hyperspectral detectors, the interpretation is still problematic, as it is influenced by various circumstances: noise level, lighting conditions, abiotic stress level, a complex interaction of the genotype and the environment, etc. The application of hyperspectral imaging in everyday farming practice will potentially allow farmers to obtain timely and precise information about the development of diseases and affected areas. This review provides an introduction into issues of hyperspectral imaging and data analysis and explores the published reports of worldwide research on the use of hyperspectral analysis in the detection of foliar fungal diseases of small-grain cereals.
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