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Engine test bench data acquisition and processing system
No full textBakalaureusetöö
Tehnika ja tehnoloogia õppekavalEesti Maaülikooli tehnikamaja mootorite katselaboris puudub sisepõlemismootorite katsestendi andmehõive- ja analüüsisüsteem. Vajalikud mõõtetulemused hõivatakse erinevates seadmetes ning kohati tuleb need manuaalselt fikseerida, mis raskendab katsete sooritamist, muudab andmete analüüsimise keeruliseks ning aeganõudvaks ja vähendab mõõtetulemuste täpsust. Bakalaureusetöö eesmärgiks oli luua kõnealune andmehõive- ja analüüsisüsteem selleks vajaliku riist- ja tarkvaralahendusega. Töö autor ühendas laboris kasutatavad mõõteseadmed – x-act kontrolleri, kütusekulu- ja õhukulu mõõturid ning heitgaasianalüsaatori katselabori juhtruumis paikneva lauaarvutiga ning kirjutas programmeerimiskeelt Python kasutades programmi, mis väljastab CSV-failina mootorite katsestendi mõõtetulemused. Andmehõiveprogramm sisaldab ka funktsionaalsust mõõtetulemuste väljastamiseks xlsx-formaadis. Andmete analüüsimisel saab programmi abil lisaks otsestele mõõtmistele leida mõningaid sisepõlemismootori tööparameetreid arvustuslikult ning genereerida mõõtetulemustele tuginevaid karakteristikuid visualiseerivaid graafikuid.
Bakalaureusetööl on praktiline väärtus – valminud mootorite katsestendi andmehõive- ja analüüsisüsteem on kavas Eesti Maaülikooli tehnikamaja mootorite katselaboris kasutusse võtta. Töö autori loodud süsteemile on võimalik lisada veel mitmeid tarkvaralisi funktsionaalsusi ning sellega saab ühendada täiendavaid sisepõlemismootorite katsetamisega seotud mõõte- ja juhtseadmeid.The engine test facility at the Estonian University of Life Sciences lacks an engine test bench data acquisition and processing system. The necessary measurements are acquired by multiple different devices and some of the results have to be logged manually, which complicates testing, makes analysing data difficult, and reduces the accuracy of measurement results. The aim of this bachelor´s thesis was to create the data acquisition and processing system in question with the necessary hard- and software solution. The author of this thesis connected the measurement devices used in the laboratory – an x-act controller, fuel consumption and air flow meters, and an exhaust gas analyser to a desktop computer located in the control room of the facility and wrote a program using the Python programming language, that outputs the measurement results of the engine test bench as a CSV-file. The data acquisition software also includes the functionality necessary to export the measurement results as an xlsx-file. In addition to measuring the operating parameters of an internal combustion engine directly, the software can also be used to calculate some indirect results when analysing data and graphs visualising engine characteristics based on test data can be generated.
This bachelor´s thesis also serves a practical purpose – the created engine test bench data acquisition and processing system is planned to be used in the engine testing facility located in the engineering building of the Estonian University of Life Sciences. The system created by the author of this thesis can be improved by increasing the functionality of its software and integrating additional measurement and control equipment used to test internal combustion engines
Estonian Musculoskeletal Disorders Questionnaire
No full textMagistritöö
Ergonoomika õppekavalTööga seotud luu- ja lihaskonna vaevused võivad põhjustada töötajale pöördumatut tervisekahju ja selle võimalikkuse vähendamiseks on oluline tundma õppida probleemi juurpõhjused, et kasutusele võtta töötajate tervist toetavad meetmed. Eestis ei ole veel välja töötatud meetodit tööga seotud luu- ja lihaskonna vaevuste uurimiseks ning siiani on kasutatud uuringute käigus teiste riikide hindamismeetodeid, mille tõlkimine eesti keelde on reguleerimata. Magistritöö eesmärk oli välja töötada kiire ja kompaktne tööga seotud luu- ja lihaskonna vaevuste esinemissageduse kaardistamise meetod eesti keeles. Magistritöö käigus selgitati välja kõige levinumad meetodid, mida inglise keeles kasutatakse (NMQ, DMQ, CMDQ ja BPI) ning analüüsiti nende meetodite eeliseid ja puuduseid. Eesti oma meetodi välja töötamine oli inspireeritud inglise keelsete meetodite eelistest ja samaaegselt nende meetodite puuduseid vältides. Kirjanduse analüüsi käigus ilmnenud teemade põhjal loodi Eesti luu- ja lihaskonna vaevuste ankeet (ELLVA). Eeltestimise käigus kontrollisid 16 Eesti Maaülikooli töötajat ankeedi rakendatavust ja andsid nõu sisu parendamise kontekstis. Keskmiselt kulus vaatlusalusel ELLVA täitmiseks ja arvamuse avaldamiseks 2 minutit ja 49 sekundit. Kõige kiirem täitmisaeg oli 20 sekundit ning kõige aeglasem 5 minutit ja 10 sekundit. Koos ankeediga töötati välja ka andmehõivet puudutav tarkvaralahendus, mis vähendab spetsialistil andmete sisestamise ja analüüsimise peale kuluvat aega. ELLVA võimaldab koguda andmeid, mis võivad aidata märgata probleemi näiteks töökeskkonnas või töölaadis ning seeläbi aidata kaasa lahenduse väljatöötamisele. Selleks, et töökeskkonnas olevate ohutegurite mõju hoida võimalikult madalal tasemel, on vaja märgata varakult võimalikke kitsaskohti, mis võivad olla seotud vähenenud tööalase heaoluga ning vajadusel sekkuda töökeskkonna parendamise eesmärgi.Work-related musculoskeletal disorders can affect the well-being of the workers and can cause irreversible health damage to the employees. To reduce this probability, it is important to learn about the cause of the problem to support the health of employees. There has not been developed a method in Estonia for quantifying work-related musculoskeletal disorders, and so far, methods developed in other countries have been used in research, but the translation of these methods into Estonian is not regulated. The aim of the master's thesis was to develop a quick and compact method for mapping the incidence of work-related musculoskeletal disorders in Estonian. The master's thesis identified the most common methods used in English (NMQ, DMQ, CMDQ ja BPI) and analyzed the advantages and disadvantages of these methods. The development of the Estonian method was inspired by the advantages of methods used in English and disadvantages of these methods were avoided as well as possible. Based on the themes that emerged during the literature analysis, the Estonian Musculoskeletal Disorders Questionnaire (ELLVA) was created. During the pre-test, 16 employees of the Estonian University of Life Sciences checked the implementation of the questionnaire and provided advice in the context of improving the content. On average, it took 2 minutes and 49 seconds to complete the ELLVA. The fastest completion time was 20 seconds and the slowest was 5 minutes and 10 seconds. Along with the questionnaire, a software solution for data analyzing was also developed, which speeds up the time it takes for a specialist to enter and interpret the data. ELLVA allows you to quantify data that can help identify a problem in the work environment or work style and thereby contribute to the development of a solution. To keep the impact of risk factors in the work environment as low as possible, it is necessary to identify potential pressure points that may be related to reduced work-related well-being and, if necessary, intervene to improve the work environment
Integrating Machine Vision and ROS for the Precise Control of a Robotic Manipulator
No full textRakenduskõrgharidusõppe lõputöö
Tehnotroonika õppekavalKäesolev töö on osa AIRE demoprojektist, mille eesmärk on arendada süsteem detailide rakiseta paigutamiseks kordinaatmõõtepingile. Ning integreerida UR3 koostöörobot, RealSense sügavuskaamerad ja ROS 2 MoveIt! 2 platvorm ühtseks süsteemiks detailide paigutuseks.
Andmed koguti YOLOv11 algoritmil põhineva masinnägemise ja sügavuskaamerate abil, süsteemi arhitektuur loodi ROS 2 platvormil
Õnnestus liidestada kõik komponendid ja määrata objektide koordinaadid, kuid roboti tegelik liikumine jäi tarkvaraprobleemide tõttu saavutamata. Töö näitas, et UR3 juhtimine ROS 2 ja MoveIt 2 kaudu vajab täiendavat arendust, kuid loodud lahendus on alus edasisteks arendusteks ja tööstuslikuks rakendamiseks.This thesis is part of the AIRE demo project focused on developing a system for fixtureless part placement onto a measurement surface.
The aim of the thesis is to integrate the UR3 collaborative robot, RealSense depth cameras, and the ROS 2 MoveIt platform into a unified system for precise object placement. Data was collected using YOLOv11-based machine vision and depth cameras; the system was built on the ROS 2 platform, including hand-eye calibration and motion planning.
While all components were successfully integrated and object coordinates determined, the robot's actual movement via MoveIt! 2 failed due to software issues. The results show that UR3 control via ROS 2 and MoveIt 2 requires further development, but the solution provides a solid foundation for future work and industrial applications
Methods for the ecological rehabilitation of Lake Harku
No full textBakalaureusetöö
Kalanduse ja rakendusökoloogia õppekavalTallinna läänepiiril asuva madalaveelise Harku järve seisund on alates 1970. aastatest olnud kehv. Tugeva inimmõju all kannatava Harku järve puhul on tegu hüpertroofse veekoguga, mille keemilise ja ökoloogilise seisundi klass on tänapäeval väga halb. Töö eesmärgiks oli uurida, millised järve tervendusmeetodid sobiksid Harku järve ökoloogilise seisundi parandamiseks. Töö kirjutamiseks on kasutatud erinevaid teadusartikleid ja erialast kirjandust. Tulemuste osas olid peamisteks allikateks Harku järves läbiviidud seired. Töö käigus selgus, et Harku järve mõjutavad nii suur välis- kui ka sisekoormus, mistõttu on järve seisundi parandamiseks vaja rakendada mitmeid erinevaid tervendusmeetodeid. Esimese sammuna tuleks vähendada valgalalt järve voolavat reostust, seejärel vähendada järve sisekoormust ja viimase meetmena tuleks taastada ökosüsteemi tasakaal läbi biomanipulatsiooni. Harku järve tervendamiskavasid on tehtud ka varem, kõige hiljutisem neist Harku järve meetmekava. Ka seal on väljatoodud nii välis- kui ka sisekoormuse vähendamise vajalikkus. Enne Harku järvel tervendusmeetodite rakendamist tuleks läbi viia täiendavad uuringud.The condition of the shallow Lake Harku, located on the western border of Tallinn, has been poor since the 1970s. Lake Harku, which suffers from significant human impact, is a hypertrophic lake whose chemical and ecological status is currently classified as very poor. The aim of this study was to investigate which restoration methods would be suitable for improving the ecological status of Lake Harku. Various scientific articles and professional literature were used in writing this paper. The main sources for the results section were monitoring studies conducted in Lake Harku. The study revealed that Lake Harku is affected by both high external and internal nutrient loading. Therefore, improving the lake’s condition requires the implementation of multiple restoration methods. As a first step, pollution from the catchment area should be reduced. This should be followed by measures to reduce internal loading, and finally, the ecological balance of the ecosystem should be restored through biomanipulation. Restoration plans for Lake Harku have been developed in the past, the most recent of which is the Lake Harku action plan. This plan also highlights the need to reduce both external and internal loading. Before implementing any restoration methods in Lake Harku, further studies should be conducted
The issues of energy-efficient renovation of apartment buildings and its impact on co-operative behaviour (example of the city of Viljandi)
No full textBakalaureusetöö
Geodeesia, kinnisvara- ja maakorralduse õppekavalKorterelamute energiatõhusaks rekonstrueerimine on Eestis väga aktuaalne, sest Eesti energiamajanduse arengukava eesmärgi kohaselt on aastaks 2030 vaja rekonstrueerimise abil suurendada hoonete energiatõhusust. Täpne eesmärk on vähemalt 50% enne 2000. aastat ehitatud korterelamutest rekonstrueerida minimaalselt C energiaklassi.
Bakalaureusetöö eesmärgiks oli leida vastused püstitatud küsimustele. Milles seisneb korterelamute energiatõhusaks rekonstrueerimise akuutsus? Millised probleemid esinevad korterelamute energiatõhusaks rekonstrueerimisel? Kuidas mõjutab energiatõhusaks rekonstrueerimine korteriühistu käitumist? Millist mõju avaldab korterelamu energiatõhusaks rekonstrueerimine hoone väärtusele?
Töö eesmärgi saavutamiseks intervjueeriti 13 korteriühistu esindajat, selleks et kaardistada rekonstrueerimise problemaatika. Korterelamute peamiseks probleemiks on amortiseerumine, sealhulgas erinevate kommunikatsioonide halvenenud seisukord. Lisaks uuriti korteriomandite hinnamuutust rekonstrueerimistoetuse maksmise algusest alates ehk perioodil 2010-2024. Enne 2000. aastat kasutusele võetud korteriomandi keskmine ruutmeetrihind oli 2010. aastaga võrreldes 2024. aastaks tõusnud 214%.The energy-efficient renovation of apartment buildings is a highly relevant topic in Estonia, as the National Energy and Climate Plan sets a goal to improve the energy performance of buildings by 2030 through renovation. The specific target is to renovate at least 50% of apartment buildings constructed before the year 2000 to achieve at least energy class C.
The aim of this bachelor’s thesis was to answer the following research questions: Why is the energy-efficient renovation of apartment buildings an urgent issue? What are the main challenges associated with such renovations? How does energy-efficient renovation influence the behaviour of housing associations? What impact does the renovation have on the value of the building?
To achieve the objectives of the study, interviews were conducted with 13 representatives of housing associations in order to map the issues related to renovation. The primary problem of apartment buildings was found to be structural deterioration, including the poor condition of various utility systems. In addition, the study examined changes in the prices of apartment ownerships from the beginning of the renovation support scheme, covering the period from 2010 to 2024. The average square metre price of apartment units built before 2000 increased by 214% in 2024 compared to 2010.https://creativecommons.org/licenses/by-nc-nd/4.0
Performance and emissions of an agricultural diesel engine with hydrogen injection under different load modes
No full textReceived: January 25th, 2024 ; Accepted: April 15th, 2025 ; Published: April 28th, 2025 ; Correspondence: [email protected] use of fossil fuels in transport sector in the last decades stimulated rise in global energy consumption in such way leaving harmful effects on human health and environment. The scale of decarbonization of transport sector in the next decade could be challenging for European Union (EU) as demand for renewable energy, like wind, solar and hydro, will definitely rise. The aim of this study is to find whether hydrogen could be optimal solution for emission reduction in agricultural machinery. In this regard, research was carried out with KOHLER KDI 1903 M diesel engine looking on main performance parameters, as also regulated emissions operating engine with conventional diesel fuel and different hydrogen injection volumes under different loads. Fuel consumption was measured with AVL KMA Mobile device, while emissions was determined using AVL SESAM FTIR exhaust gas analytical system. During the tests, it was observed that the addition of a higher hydrogen concentration provides more substantial benefits that includes a larger impact on fuel consumption and carbon dioxide (CO2) emissions. Other emissions such as carbon monoxide (CO) emissions had smaller but positive impact, while the addition of hydrogen gas had various impact on nitrogen oxide (NOx) emissions. At the same time decrease in particulate matter (PM) emissions was observed with higher hydrogen concentrations and more substantial impact was observed during higher load conditions and higher hydrogen concentration
Gentrification and Overtourism in Permanently Inhabited Small Islands of Estonia
No full textMagistritöö
Loodusturismi õppekavalEesti väikesaared ajas muutunud – traditsioonilise püsiasustusega iseloomulikud kogukonnad on jäänud väiksemaks, põliselaniku ja püsielaniku vahelised piirid on hägustunud ja saarel olevat kinnisvara ostetakse kokku jõukamate huviliste poolt, mis tõstab ka kinnisvara hinda. Varasemad uuringud on käsitlenud gentrifikatsiooni Eesti suuremates linnades (Tallinn, Tartu) ja Lahemaal. Ületurismi Eestis on käsitletud vähe. Eestis pole seni teada, millisel määral võivad gentrifikatsioon ja ületurism olla seotud väikesaartel toimuva rahvastiku muutumise, ruumilise ümberkujundamise ja kultuurilise nihkega. Samuti pole selged nende kahe nähtuse omavahelised seosed väikesaarte kontekstis; seosed kohaliku sotsiaalse, kultuurilise ja ruumilise keskkonnaga ning nende protsesside tagajärjed kogukondade kestlikkusele. Töö eesmärk on mõista gentrifikatsiooni ja ületurismi Eesti püsiasustusega väikesaartel ning hinnata nende tegurite rolli kohaliku kogukonna jätkusuutlikkusele ja saarte elukeskkonna arengule. Töö põhineb mitmejuhtumi-uuringul, mille valimiks olid viis püsiasustusega väikesaart Eestis: Abruka, Kihnu, Prangli, Ruhnu ja Vormsi. Eesmärgi täitmiseks kasutati kvalitatiivuuringu meetodit, narratiivi, kus läbi analüütilise jutustuse leiti uuringu jaoks olulised mõisted ja meetodid. Eesmärgipärasesse valimisse otsiti väikesaarte elanike seast: põliselanike; elanike, kes on saarele kolinud 1990-00ndatel ja elanike, kes on saarega seotud viimase +2-10 aasta jooksul. Osad neist olid seotud turismisektoriga. Narratiivsed intervjuud viidi läbi 20 väikesaare elanikuga. Töö tulemused näitavad, et gentrifikatsioonil ja ületurismil on nii väikesaartele pärssivaid kui soodusvavaid mõjusid. Ühisosana leiti, et gentrifikatsioon ja ületurism saavad eksisteerida väikesaarel läbi füüsilise ruumi, kui sisserändajad ja turistid koonduvad samasse piirkonda ning peletavad sellega eemale püsielanikke. Mõlema ilmingu mõjude leevendamiseks on oluline kaasata kohalikke elanikke otsustusprotsessidesse ja luua arengukavad, mis haakuksid saare püsielanike visioonidega. Edasised uurimisvõimalused võivad olla seotud kogukonna suhete ja koormustaluvuse uuringutega.Estonia’s small islands have undergone significant transformation over recent years. Traditional, permanent-resident communities have noticeably declined, and distinctions between native islanders and year-round residents have become increasingly ambiguous. Rising demand for island properties among wealthier buyers has led to notable increases in real estate prices. Existing research in Estonia has primarily focused on gentrification within larger urban centers such as Tallinn and Tartu, as well as in Lahemaa. The phenomenon of overtourism has received limited scholarly attention. There remains considerable uncertainty regarding the extent to which gentrification and overtourism are linked to demographic changes, spatial transformation, and cultural shifts on Estonia’s small islands. The interplay between these phenomena, particularly their connections to the social, cultural, and spatial environments of small islands and their implications for community sustainability remains largely unexplored. This study sets out to examine the interplay between gentrification and overtourism on Estonia’s permanently inhabited small islands, specifically focusing on how these phenomena impact community sustainability and the development of the islands’ living environments. The research adopts a multi-case study approach, targeting five Estonian islands with established year-round populations: Abruka, Kihnu, Prangli, Ruhnu, and Vormsi. Employing a narrative-based qualitative methodology and analytical storytelling, seeking to distill key concepts and perspectives. To ensure a comprehensive view, participants were strategically selected: native islanders, individuals who relocated during the 1990s and 2000s and those with more recent connections (within the past 2–10 years). Some interviewees also had ties to the tourism sector. In total, researchers conducted 20 narrative interviews. Findings suggest that both gentrification and overtourism present a mix of challenges and opportunities for small island communities. A notable pattern observed is the tendency for newcomers and tourists to cluster in particular areas, which can inadvertently displace longer-term residents. Addressing these dynamics effectively requires meaningful involvement of local residents in decision-making processes and the development of growth strategies that align with the long-term aspirations of the island communities. Further research is recommended in the areas of community relations and studies on the carrying capacity of these unique environments
Tõhela
No full textPhytoplankton biomass, diversity and abundance in samples collected from Lake Tõhela during the period 1929-2018
Evaluation of grain morphometry and gliadin diversity among twenty accessions of the genus Aegilops from the National collection of Bulgaria
No full textReceived: August 25th, 2024 ; Accepted: January 31st, 2025 ; Published: February 10th, 2025 ; Correspondence: [email protected] objective of the study was to evaluate the genetic diversity in twenty Aegilops accessions belonging to five plant species with respect to specific grain morphometric parameters and gliadin proteins, employing digital image analysis and A-PAGE electrophoresis. The considerable variation was observed among accessions for grain morphometric traits - area, perimeter, length, width and colour of grain. A total of 96 gliadin polymorphic bands were identified, with the number of bands varying between 13 and 22 per accession. The overall genetic diversity in the samples based on the patterns observed for each of the four gliadin regions showed that the ω, γ and β regions had high genetic variation index (H = 0.950), while α regions (H = 0.938), respectively. The mean genetic diversity estimate was high (H = 0.947). The average genetic similarity between all 20 genotypes ranges from 0.14 to 0.93 with a mean of 0.56, indicating that the studied accessions exhibited considerable genetic variability. The study found that the clustering of Aegilops genotypes was not linked to their geographic origin. Two-dimensional Principal Coordinates Analysis (PCoA) based on the gliadin and morphometric analyses revealed wide genetic dissimilarity between most of the genotypes, explaining 97.16% of the variations, with the model explaining 97.16% of the observed variation. Of this, PCo1 accounted for 93.65% and PCo2 for 3.51%. Genotypes with analogous genomes were grouped in close proximity within the phylogenetic tree, indicating that their evolutionary relationships may have originated from the same parental lineage
Väimela Alajärv
No full textPhytoplankton biomass, diversity and abundance in samples collected from Väimela Alajärv during the period 1962-1989