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A review on semi-transparent solar panels application on greenhouse rooftops
2024
Lozbergs, Arturs | Vartukapteinis, Kaspars | Kancevica, Liene
This paper provides an overview of recent progress reached in semi-transparent photovoltaic systems (STPV), which are being assessed as a potential solution to enhance the productivity of plant grown in greenhouses. Utilizing this kind of renewable energy resources, relating with plant growing is attractive solution to increase sustainability for citizens. The aim of this study is to find out recent advances for application of various semi-transparent photovoltaic systems which can be integrated in greenhouses. Solar PVs are among dependable, mature and cost-effective renewable energy systems and solutions, which are promising for building integrated photovoltaics (BIPV) application. The main emerging photovoltaic candidates for BIPV are amorphous silicon, kesterite, chalcopyrite, CdTe, dye-sensitized, organic and perovskite based systems. A monographic study approach has been utilized in this investigation, in ordain to compile and analyse the photovoltaic systems for BIPV mainly investigating and comparing two main parameters: average visible transmittance (AVT) and power conversion efficiency (PCE). The rapid development of new materials and structures for the manufacture of semi-transparent solar panels allows a balance to be struck between AVT, PCE and a comparison of the reviewed materials indicates that organic and perovskite are the most promising for semi-transparent solar panel production and application in greenhouse constructions, based on their PCE and AVT results.
显示更多 [+] 显示较少 [-]Data acquisition system for vehicle engine sensors: A review
2024
Melders, Lauris | Smigins, Ruslans | Birkavs, Aivars
Monitoring the operation of car engines using a smartphone and cloud services is a concept that falls within the field of intelligent vehicle technologies. Using information collection system, vehicle fleet companies can effectively manage the usage of their vehicles, minimizing investment and maintenance costs, preventing accidents and failures, identifying poor driving behaviour among employees, and reducing expenses associated with fuel, tires, and other resources. This approach involves collecting real-time data from the vehicle engine sensors, transferring data to the cloud via a smartphone, and then using cloud services to analyse and manage the information, making it understandable in a simple way. This review reflects on the working efficiency of internal combustion engines and the reduction of pollution to the environment, also gathers existing literature to gain insights into vehicle sensor data acquisition technology and systems in the automotive industry identifying gaps in current knowledge and provide a conceptual framework for next practical research in this field. After explaining the general idea of logistics tasks in technology development, various sensors and their methods are associated with engine properties are introduced. The research results show that most articles are about data acquisition systems from different systems. They can provide convenience and flexibility for users, allowing them to easily access and adjust settings on-the-go, enabling real-time monitoring and adjustment of engine performance, helping users optimize efficiency and performance based on their specific needs and preferences.
显示更多 [+] 显示较少 [-]The deformation monitoring system on the Brasa overpass in Riga [Latvia]
2024
Kraskevičs, Edgars | Celms, Armands | Rusinovs, Jevgenijs
Engineering structures such as bridges, overpasses, and viaducts constitute a crucial component of the infrastructure of any industrial city. The wide-scale industrialisation of the twentieth century transformed the urban landscape. Many designs and solutions have become morally and physically outdated since those times, yet their usage continues, which is not always safe. With the aging of infrastructure, the issue of their further safe use inevitably arises. Geodetic monitoring of structural deformations can provide control and safety, as well as gather data for designers and engineers. The data collected by deformation monitoring systems should form the basis for the reconstruction and maintenance project of infrastructural facilities. Deformation monitoring systems are designed for each object based on the parameters of the structure, taking into account the constructive features, materials, and the importance of the infrastructural object to the city traffic. It is not always possible to completely close an overpass during reconstruction, as this would affect the transport flow in a specific district of the city. Monitoring of recently put into operation structures will ensure the collection of deformation data for the survival analysis. Once the structural health is defined, the period of service life until scheduled maintenance will be determined. As a result of our research on the Brasa overpass in Riga, we developed a scheme for swift response to signals from the monitoring systemʼs sensors. Additionally, we ensured the safe operation of the old overpass during the construction of the new one by promptly utilising data obtained from the deformation monitoring system.
显示更多 [+] 显示较少 [-]The [European Green Deal] as a factor for changes in business: the educational perspective
2024
Beizitere, Ilona | Brence, Ieva | Rivza, Baiba
Sustainability, green growth and the European Green Deal principles are the cornerstones that should and will affect our lives. The aim of the paper is to provide possible improvements to higher education programmes to promote the implementation of the European Green Deal as a factor for changes in business. The research is based on investigations into the entrepreneurship students’ knowledge of the European Green Deal. A theoretical analysis of literature and policy documents were investigated to develop an appropriate questionnaire for the survey of Latvian university students. The research methods involve measures of central tendency and location, T-test, ANOVA and correlation analysis. The research results indicate that business curricula involve courses on Sustainable Development and universitiesʼ role in teaching the Green Deal because the students who hold experience in entrepreneurship report similar results if compared with students without experience in entrepreneurship. Students’ knowledge of the European Green Deal should be improved since there are a number of aspects where the answers were not correct. This, in turn, prompts the need to strengthen and diversify education, so that business transformation towards the Green Deal is successful. The curricula should be further improved, as it allows students to better understand EU and global trends in saving the planet and put the knowledge into practice in their companies.
显示更多 [+] 显示较少 [-]Development of professional communicative competences of students’
2024
Davlatov, Keldiyor | Ilieva, Lola | Djumaniyazova, Malohat | Murtazaeva, Aisafar
In our republic in the process of preparing students for professional activity one of the urgent tasks is considered to be the development of their professional speech. It is very important for todayʼs specialist to be competent, competitive and able to communicate effectively in his future activity. However, the main problem is the teaching of professional culture and the holistic development of professional communicative competences. The aim of the article is to develop recommendations and methodological guidelines to ensure the cultural communication of future professionals. In particular, the experiment proves that the student should feel the benefit of learning a foreign language in the future and get used to independent work on the subject, and gradually the motivation to learn the language will appear. The study highlights the role of foreign language teaching in the interdependence of ‘language – communication – profession – cultureʼ, the interdependence of language and culture in the development of language skills, the systematic approach to the study of professional terms. It is a well-known fact that students, in addition to acquiring lexical and grammatical knowledge of a foreign language, should also have a perfect command of the culture and values of their country and of the country where the language is learnt. In order to effectively implement the business communication situation in the classroom, it is desirable for the student to ‘understand the foreignerʼ, to study and master the culture of the foreign country, the accepted rules and values. While doing research, the methodological recommendations and instructions for the systematic organization of foreign language teaching are given.
显示更多 [+] 显示较少 [-]The use of artificial intelligence by students of Information Technology programmes
2024
Sergejeva, Natalija | Vronska, Natalja | Briede, Baiba | Samuilik, Inna
The use of artificial intelligence (AI) tools in university education is a phenomenon of various directions: the potential of AI tools, skills, purpose and sense of usage. Each direction is worth of working out and introducing regulatory systems and deeper investigating users’ choice and managing the process of getting, navigating and creating information by means of AI. Therefore, one of the emerging scientific challenges is students’ abilities and personalised learning experience in the use of AI. The study is focused on the usage of AI in specific courses, and namely the students of Information Technology (IT) programmes from Latvia University of Life Sciences and Technologies (LBTU) and Riga Technical University (RTU). The aim of the study is to investigate the students’ ability, need and merit to use AI in learning numerical methods, mathematics and programming. The main data collection method used is a student survey. According to the main results, it is found out that respondents when solving the programming tasks sometimes used AI, while solving mathematical tasks respondents rarely used AI. AI actually did not help to solve the mathematical tasks, while it partly helped to solve the programming tasks. The use of AI partly helped the respondents to improve the knowledge and skills of programming. Acquiring the study course Numerical Methods respondents mainly used ChatGPT, but performing practical works respondents mostly did not use AI.
显示更多 [+] 显示较少 [-]The need and role of high-level math skills in engineering studies
2024
Zvirgzdina, Liga | Kopeika, Evija
This article examines the importance and necessity of high-level mathematical skills in engineering studies. It analyses the specific mathematical skills required for successful engineering education and their role in engineering studies. The results provide insight into how high-level mathematical skills contribute to the development of engineering competencies and enable engineers to solve complex problem scenarios. Key findings reveal that high-level mathematical skills are indispensable in engineering education, providing the tools needed to solve real-world problems and drive innovation in engineering. Mathematics is the language of engineering. It provides the analytical and problem-solving tools necessary for engineers to design, analyse, and optimize systems, ensuring that they meet safety, efficiency, and performance requirements. Engineers use math as a fundamental tool to make informed decisions and drive technological advancements across various engineering disciplines. Without math, engineering would be severely limited in its ability to design safe, efficient, and innovative solutions to the complex problems that engineers encounter in various industries. The questions contained in the article are investigated using survey data of university students. The purpose of this study is to research the relative applicability and level of knowledge of the learning material learned in secondary educational institutions in mathematics, based on the experience of school graduates and engineering students.
显示更多 [+] 显示较少 [-]Use of automatically obtained data in the quantitative and qualitative evaluation of harvester operator training
2024
Strubergs, Aigars | Sisenis, Linards | Sarmulis, Ziedonis
The study aims to find out the efficiency of periodic training of the harvester (cut-to-length) operator, using the automatically saved data of the harvesterʼs information system. It has been established that logging service providers and training institutions do not analyse the operatorʼs work before starting the training; therefore, the training is carried out according to certain, standard programs, without going into the previous performance of each trainee operator. The research uses data automatically saved by Ponsse harvesters during the year, obtained from Ponsse Manager. The study found that by using automatically saved data of the harvester information and performing data grouping with subsequent analysis, it is possible to determine the progress in the execution of specific stem processing operations and to identify operations where the instructor should pay increased attention during training. The research analysed the data of 3 operators, obtained while working with Ponsse harvesters in clear-cutting. In the study, it was found that operator A reduced stem processing time by 3%, labour productivity increased by 15%, and fuel consumption per l m⁻³ decreased by 14% over 3 months. Operator B, after training, saw a 20% reduction in stem processing time, a 13% increase in work productivity, and a 5% increase in fuel consumption l m⁻³ over 3 months. Operator C had a 10% increase in stem processing time, a 1% increase in labour productivity, and a 2% increase in fuel consumption l m³ after training.
显示更多 [+] 显示较少 [-]The composition and richness of ground cover vegetation in drained forest stand
2024
Liepina, Agnese Anta | Jansone, Diāna | Samariks, Valters | Jansons, Āris
Forest drainage is a common management practice, carried out in order to improve tree growth; however, the alterations in hydrological and microclimate dynamics can cause diverse changes in the characteristics of ground cover vegetation. The aim of study was to characterise the composition and richness of ground cover vegetation in drained forest stands, where the groundwater levels have been affected by the reconstruction of drainage diches. Research was conducted in the hemiboreal forests of Latvia. Three study sites were chosen, measurements of groundwater level, stand parameters and projective cover of ground covered vegetation took place in two stands which underwent reconstruction and restoration of the drainage system in 2019, and a control stand, where the drainage system had not been restored. For assessing the relationship of ground cover vegetation in relation to groundwater level and stand factors, DCA analysis was used. The differences between stands, regarding the species projective cover and species composition, were assessed by ANOSIM (Analysis of similarities). Sites, where drainage ditches were fully or partially reconstructed exhibited a greater diversity of ground cover vegetation species compared to the control stand, where no renewal of drainage ditches had occurred. Conversely, the control stand displayed a higher projective cover of the bryophyte layer. The composition of ground cover vegetation species differed amongst all studied stands, the varying stand characteristics and co-dominant tree species in canopy layer had a more pronounced influence on ground cover vegetation, making it complicated to evaluate direct impact of groundwater level.
显示更多 [+] 显示较少 [-]Rosemary essential oil by hydrodistillation: SPME-GC-MS characterization
2024
Calvo-Gomez, Octavio | Ruzibayev, Akbarali | Akramova, Rano | Salijonova, Shakhnozakhon | Gaipova, Shakhnozakhon | Khodjaev, Sarvar
Rosemary (Salvia rosmarinus) is an aromatic herb with a multitude of uses. It is both a seasoning in various dishes, and a natural remedy for several diseases mainly due to its anti-inflammatory and anti-oxidative effects. Plus, it is also used in cosmetic industry and for improving agriculture practices and helping the environment, since it may be a natural antimicrobial. It is worth noting that this plant is also grown and commercialized in Uzbekistan, thus, if added value is given to rosemary’s products, it has potential for improving living conditions and helping in the economy of local farmers and entrepreneurs. In this work, we discuss a technique for obtaining rosemary essential oil, rich in terpenes, by vacuum assisted hydrodistillation. This is a solventless environmentally friendly and safe technique that allows the obtention of an added value rosemary product where terpenes, compounds responsible for most of rosemary’s properties, are the most abundant. Two samples of locally acquired rosemary were sourced, essential oil was extracted, and characterization was then performed by Solid Phase Micro Extraction (SPME) and Gas Chromatography – Mass Spectrometry (GC-MS). As a comparison, a direct injection of a dilution of one of the essential oil samples was also performed. It was concluded that samples of essential oil obtained from both sources were entirely composed of terpenes or terpene derivatives. Besides, SPME was a superior method when compared to direct injection, since a larger number of volatiles was able to be identified.
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